prompt_front: Now, answer the following question based on the text below, only give me the answer and do not output any other words.

Question: What happens to the high resolution of what we focus on at dawn or dusk?

Read the following text and answer briefly.

Context 1: Inner Reality Unveiled
Inner Reality Unveiled
by DragonFly on April 18th, 2018, 10:54 pm
There is no direct (literal) view of the actual reality 'out there'  Our inner viewport is ever only that of the model (qualia) of inner and outer reality built by the brain  We see/sense nothing but this model made inside the brain 
We don't see across a room or any scene but only across the model of the room/scene  We don't look through a microscope at an actual object but only look at a model of that object  You get the idea  A reflective color spectrum is used to make it look like that more distinctive color is a surface property of an object modeled 
The brain doesn't model everything, as a lot of it would be clutter, and for what remains as useful to portray the brain still doesn't have the resources to model everything at high resolution and so thus whatever we focus on gets all the high res detail put into it just in the nick of time when we look/focus  At dawn or dusk this high resolution becomes a bit less on what we focus on so that what's off to the left or right can be better noted in the dim light 
So far, nothing astounding here to us, although maybe to everyday folk that we only ever see the inside of the head/brain—the model 
Of course, the shocks get worse, such as that our intentions cannot be those of first cause, self-made people, but from prior causes that we weren't able to choose and be responsible for  What is left, in short, is the freedom of action for these inbuilt intentions to operate, at least when not prevented by the weather or any other controlling factors, which 'freedom of action' amounts to compatibilism 
Other notes on the above are that while we can never know if everything is deterministic, although we know that a lot is, whatever is indeterminate diminishes our modeling and our consistency 
Re: Inner Reality Unveiled
by DragonFly on April 20th, 2018, 3:14 pm
To continue, many feel that the model/qualia is very rich, but there's not anything to compare it to  Some creatures have a fourth primary color to work from and some have more smells and better hearing  Our colors (reflective spectrum) go through some averaging because of the various close frequencies about, but they still have a lot of pop to them  The model seems to be super real, where it has the focused detail, meaning better than real, or super real or surreal; surely colors win out over a bunch of waves (if they could be seen), these colors being very distinctive, which high contrast is what the model seems to be about  Away from the center of focus, the model has to be worse than cartoonish 
Other qualia properties are intense, too, such as pain being able to be very painful, to the max, and such 
Qualia are based on initial isomorphic maps, meaning topographical, when representing the territory  For sounds, the map is for tones from the air vibrations, and for smell it is scents from the molecule shapes; for touch it is a body map  The isomorphism may get carried through even three levels of models, whereafter it seems to become more symbolic and less isomorphic, perhaps indicating that the information is ready to turn into qualia, the point at which the 'hard problem' manifests  It is thought that at least four levels of modules are required for the 'magic' of phenomenal transformation to occur; we have the problem surrounded but not yet solved  Perhaps it is enough to have a truth in lieu of its proof—that there is ontological subjectivity, meaning that it exists, although it may not be fundamental or miraculous 
So, in sum so far, direct realism is an illusion, but is a very useful illusion, which we might better call a fine representation by the model, since the word 'illusion' is more about what's wrong as not really showing its object as substantial and really being behind it  Dreams, then, would be better called illusions; further they demonstrate the power of the structure of the model  When we inspects objects in dreams they look just as good as when we see them awake, although backgrounds come and go inconsistently and there are narrative gaps (all of a sudden we are driving a vehicle without ever having gotten into it, plus the controls are a mystery )
Another illusion is the feeling of having all of the information in a qualia scene as instantly available, as well as feeling that it is all happening in real time, plus that one is directing it all right then and there 
by mitchellmckain on April 21st, 2018, 4:33 am
Yes and all those security cameras in the banks and stores must be a joke because anybody watching cannot see us but only see images on a display screen 
by DragonFly on April 21st, 2018, 12:05 pm
mitchellmckain » April 21st, 2018, 3:33 am wrote: Yes and all those security cameras in the banks and stores must be a joke because anybody watching cannot see us but only see images on a display screen 
You forgot that what the brain maps and models is a reliable representation of what's out there and in here 
by mitchellmckain on April 21st, 2018, 12:16 pm
DragonFly » April 21st, 2018, 11:05 am wrote:
I was being sarcastic in order to point out this very fact  Whether images on a display screen or human consciousness, they are reliable representations and that means they do see what is really out there  The fact that this is indirect is not without logical implications, but not to the extent that you can say we do not apprehend an objective reality 
by TheVat on April 21st, 2018, 12:29 pm
The evolutionary argument is a strong one, also, for the accuracy of our sensory representations of the external world  If you think a tiger's tail is a pretty flower, and try to pluck it, you won't be around long to reproduce 
I invite anyone who thinks that bus hurtling down the street is nothing but a model in the brain to step in front of it 
Your impression of the bus may be indirect, but it has a direct causal chain of connections to the actual bus out there  You are a photon collector, absorbing photons bounced off a bus  That way, it doesn't have to be you that's bounced off the bus 
by DragonFly on April 21st, 2018, 2:19 pm
Mentally healthy responders need not worry about any unreliable representations due to there being no direct realism  As I showed, the representations are even improvements that bring out what is distinctive and important, as well as my indicating of an 'out there'  (The sarcasm thus fell doubly flat, run over by the bus, either because that mode is the nature of the person or this short thread wasn't read well )
The world out there indeed comes to us (we don't reach out and probe it but for such as feeling our way in the dark), via photons for sight, and similarly comes to us in other ways for the other 'distance' senses  That the brain projects the objects back out there where they are, with depth (objects whose radiation came into us) is very useful  This trivia is mentioned here for completeness, for non scientific readers, but all the like herein is not contested 
Back on track now, with derailment attempts ever unwelcome, but actual meaty posts extremely welcome, many neurologists note that awake consciousness doesn't easily get snuffed out, for a people may have many and various brain impairments yet they remain conscious, which, in short, without going through them all, indicates that there probably isn't any one 'Grand Central Station' where consciousness originates but that it may arise from any suitable hierarchy of brain modules 
Consciousness, like life, requires embodiment, and is now thought to have been around in some form since the Cambrian explosion  As evolution proceeds via physical processes it rather follows that consciousness does too  Billions of years of small steps from a stable organism platform can acculuminate into what otherwise seems a miracle, but then again, miracles are instant  When extinction events wipe everything out, the process just starts up again, and probably has, several times over 
Since qualia are structured, such as I described, plus healing the blind spot and more that wasn't put here, this again suggest that qualia have to be constructed from parts the brain has made from interpretations via physical processes 
How the phenomenal transform springs out remains as the central mystery of all  We think that there are larger mysteries, such as if there is any ultimate purpose to Existence, but this one is easy, for it can be shown that there can be no ultimate purpose  (There can be local and proximate purpose ) More an this another time or place 
by mitchellmckain on April 21st, 2018, 4:00 pm
I shall interpret the above as a request for a detailed point by point response to the OP 
DragonFly » April 18th, 2018, 9:54 pm wrote: There is no direct (literal) view of the actual reality 'out there'  Our inner viewport is ever only that of the model (qualia) of inner and outer reality built by the brain  We see/sense nothing but this model made inside the brain 
But this is wrong, derived from delusional semantics as if "seeing" meant absorbing the objects themselves into our brain and mind  Of course, "seeing" means no such thing  "Seeing" means gathering data to construct a mental model of an external reality  We don't, in fact, "see" this inner model at all  This "model" is a product of speculation and abstraction in meta-conscious process of self-reflection 
Our inner viewport is thus one of looking out at the outer reality and not one of looking at the model  We do see across a room -- USING a mental model  We do not see the mental model except by speculative imagination  The most we can say is that by using such a process of mental modeling in order to see, there can be deviations due to a variety of neurological and mental processes being involved, including the role of beliefs in our interpretations  Thus our perceptions cannot be fully separated from our beliefs and our access to the world is fundamentally subjective  The objective can only be fully realized by a process of abstraction through communication with others 
DragonFly » April 18th, 2018, 9:54 pm wrote: The brain doesn't model everything, as a lot of it would be clutter, and for what remains as useful to portray the brain still doesn't have the resources to model everything at high resolution and so thus whatever we focus on gets all the high res detail put into it just in the nick of time when we look/focus  
DragonFly » April 18th, 2018, 9:54 pm wrote: Of course, the shocks get worse, such as that our intentions cannot be those of first cause, self-made people, but from prior causes that we weren't able to choose and be responsible for  What is left, in short, is the freedom of action for these inbuilt intentions to operate, at least when not prevented by the weather or any other controlling factors, which 'freedom of action' amounts to compatibilism 
Your philosophical conclusions here will not be mistaken for scientific observations  Your interpretations are based on your own presumptions which I reject as incorrect  The process of human intention and action is certainly a complex one but the fact remains that the first causes do exist  People may be capable of simply watching much of their life pass by as an minimally participating observer (with all sorts of fatalistic and compatibilist dodges and delusions of objectivity), but others choose to take ownership of the first causes within them as a fully responsible participants in their own life 
Also as I have mentioned numerous times before, there is nothing absolute or guaranteed about this freedom of will  It can certainly be greatly diminished by a great number of things such as drugs, illness, habits, and even beliefs  This just means that we are ill advised to judge others according to our own perception and choices 
DragonFly » April 18th, 2018, 9:54 pm wrote: Other notes on the above are that while we can never know if everything is deterministic, although we know that a lot is, whatever is indeterminate diminishes our modeling and our consistency 
We can know that the experimental results show that there are events not determined by any hidden variables within the scientific worldview  People are free to ignore these results and stubbornly cling to presumptions to the contrary but they are being unreasonable if they expect other people to accept the conclusions which they are deriving from such willfulness 
And to head off the typical strawmen, I am not claiming that determinism has been disproven any more than the scientific evidence for evolution disproves divine intelligent design  Science is not a matter of proof, but of accepting that what the evidence and experimental results show us are the basis of what is reasonable to accept until there is evidence to the contrary 
mitchellmckain » April 21st, 2018, 3:00 pm wrote: But this is wrong, derived from delusional semantics as if "seeing" meant absorbing the objects themselves into our brain and mind  Of course, "seeing" means no such thing  "Seeing" means gathering data to construct a mental model of an external reality  We don't, in fact, "see" this inner model at all  This "model" is a product of speculation and abstraction in meta-conscious process of self-reflection 
Yes, the view point is within the model  We don't literally 'see' across a room  The model gets 'viewed' and navigated and noted and whatnot  The outer reality is not able to be viewed directly but is usefully "looked out at" through a representation  Do you directly see wave frequencies air vibrations, and molecule shapes? I didn't mean 'seeing' in the sense of eye stuff, but I note the word problem 
mitchellmckain » April 21st, 2018, 3:00 pm wrote:
Yes, I was reading a large road sign with many words and the words at the bottom didn't come into focus until I got down to them  Our computers have many more terabytes than the brain has 
mitchellmckain » April 21st, 2018, 3:00 pm wrote: Your philosophical conclusions here will not be mistaken for scientific observations  Your interpretations are based on your own presumptions which I reject as incorrect  The process of human intention and action is certainly a complex one but the fact remains that the first causes do exist  People may be capable of simply watching much of their life pass by as an minimally participating observer (with all sorts of fatalistic and compatibilist dodges and delusions of objectivity), but others choose to take ownership of the first causes within them as a fully responsible participants in their own life 
Total libertarians do claim that they are first cause, self made people at every instant  How does this work? A theory of conscious intentions happening without any underlying physical processes ('you') behind them is the toughest sell of all proposals on the will, so it's no wonder that this 'being free of the will' can't be shown  Plus, why does one want this? Perhaps a distaste for having a will that wills things in the subconscious dark  These trillions of connections firing are not portrayed in consciousness, thank goodness 
Yes, as I said, some is indeterminate, so there is no ignoring  (You don't seem to read well, even when seeing it again when you quote it ) The more indeterminacy the worse we are able to carry our our ability to operate, which minimal and trivial capability is called 'freedom of action'  So be it  We have learned something  People want more than this, though, and so they will have to show that that's possible while still retaining the self/will  How is responsibility gained at any point when one was never responsible for prior causes toward one's being/self that couldn't be chosen?
So, prison time need not be assigned for retribution only, more compassion can be granted for those who did as they had to, and we come to better understand our place in the universe  Life is great for experiencing and living, and fatalism isn't recommended, for it could work against the enjoyment 
P S  There is no point at which ultimate purpose/intention could have been applied to what is eternal, as well as none to be applied to something springing from nothing (which, though impossible, I include for completeness, for the "springing" capability would still be an eternal 'something' )
It's fine with me if you want a fully formed Being with a system of intelligence to be there First, amid nothing else, but to stick to the template of ID, then a Higher ID had to be behind it, etc , or we could just forget about the one-off usage golden template of ID  The universe looks to be tuned, if it is, for mostly a lot of hydrogen gas in endless sparse spaces  It took ten billion years for us to be able to persist a bit in our rarity amid the waste  [/quote]
DragonFly » April 21st, 2018, 3:57 pm wrote:
Yes, as I said, some is indeterminate, so there is no ignoring 
Incorrect  You did not say "some is indeterminate " So either you do not write well, cannot understand the logic of your own words, or you make up things as an excuse to attack other people  In fact, this can be identified with a logical fallacy  "Whatever is indeterminate diminishes our modeling" means our modeling is diminished IF there is anything indeterminate  If A then B does not allow you affirm A, so by equating these two you have committed a logical fallacy  Furthermore it is amazing how far out on a limb you go to concoct such an attack  You said, "we cannot know if everything is deterministic," which is utterly inconsistent with a clam that "some is indeterminate," because if some is indeterminate then you would know that it is NOT deterministic 
DragonFly » April 21st, 2018, 3:57 pm wrote: Total libertarians do claim that they are first cause, self made people at every instant 
The philosophers who claim that we have free actions are called libertarians  The radical opposition that libertarians pose to the determinist position is their acceptance of free actions  Libertarians accept the incompatibility premise that holds agents morally responsible for free actions  Incompatibilism maintains that determinism is incompatible with human freedom  Libertarians accept that there are free actions, and in doing so, believe that we are morally responsible for some of our actions, namely, the free ones 
The libertarian ONLY claims that we do have free will actions and affirm the incompatibility of determinism with free will  There is no claim here that free will is absolute, inviolable, and applies to every action and thus that people are "self made at every instance "
Thus in the following it is clear you are burning an absurd strawman 
DragonFly » April 21st, 2018, 3:57 pm wrote: How does this work? A theory of conscious intentions happening without any underlying physical processes ('you') behind them is the toughest sell of all proposals on the will, so it's no wonder that this 'being free of the will' can't be shown  Plus, why does one want this? Perhaps a distaste for having a will that wills things in the subconscious dark  These trillions of connections firing are not portrayed in consciousness, thank goodness 
Someone only claims the opposition is selling something absurdly silly because they want to make something only slightly less absurd and silly sound reasonable by comparison  But to make sure you understand   
1  Nobody HERE is selling a theory of conscious intention without any underlying physical processes 
2  Nobody HERE is claiming any "being free of the will"
These are indeed nonsense 
1  As a physicalist with regards to the mind-body problem I oppose the idea of conscious intention without any physical processes  Nor would I assert that there are no unconscious processes underlying our conscious intentions  But as I explained in another thread just because there are such processes does not mean we have no responsibility for them or that our intention does not constitute a conscious cause of our action 
2  As a libertarian it is absurd to think free will means freedom from the will  What we reject is the attempt to separate the self from desires and will as if these were some external thing forcing people to do things  This is nothing but pure empty rhetoric on the part of the opposition  Freedom from the will is the OPPOSITE of free will  If you are not acting according to your desire then this is an example of actions without free will 
DragonFly » April 21st, 2018, 3:57 pm wrote: The more indeterminacy the worse we are able to carry our our ability to operate, which minimal and trivial capability is called 'freedom of action' 
Incorrect  This is only because you equate freedom with control  It is not the same thing  Besides the indeterminacy in the laws of physics is only with respect to a system of mathematical laws  It doesn't really say that nothing causes the result, but only that there are no variables to make the exact result calculable 
DragonFly » April 21st, 2018, 3:57 pm wrote: How is responsibility gained at any point when one was never responsible for prior causes toward one's being/self that couldn't be chosen?
Again it is because free will does not equal control  Free will only means you choose how to respond to the situation  It does require an awareness of alternatives, but it does not require an ability to dictate exactly what will happen in the future 
DragonFly » April 21st, 2018, 3:57 pm wrote: So, prison time need not be assigned for retribution only, more compassion can be granted for those who did as they had to, and we come to better understand our place in the universe  Life is great for experiencing and living, and fatalism isn't recommended, for it could work against the enjoyment 
While imprisonment may be an improvement over the old English law, the inadequacies are legion  It was indeed invented as a means of reforming the convicted even if it fails to accomplish this very well  To be sure, "retribution" is a lousy basis for a system of justice  But the point of "mercy" isn't just compassion but to acknowledge the fact that mistakes are part of the process by which we learn  Therefore, coming down on people like a load bricks for any mistake is counterproductive  On the other hand, we would be foolish not to consider whether a person in question is showing any ability to learn from their mistakes  If not, a change of environment/circumstances is probably called for, even if today's prisons largely fail to be environment needed 
Observe that this analysis of justice and mercy has nothing whatsoever to do with free will  The government of a free society should be founded upon what can be objectively established and free will is not one of these things  In the above consideration of justice and mercy, the question of whether a person truly has free will is completely irrelevant 
DragonFly » April 21st, 2018, 3:57 pm wrote: It's fine with me if you want a fully formed Being with a system of intelligence to be there First, amid nothing else, but to stick to the template of ID, then a Higher ID had to be behind it, etc , or we could just forget about the one-off usage golden template of ID  The universe looks to be tuned, if it is, for mostly a lot of hydrogen gas in endless sparse spaces  It took ten billion years for us to be able to persist a bit in our rarity amid the waste 
I consider Intelligent Design to be attack upon science -- shoving theology into a place where it clearly does not belong  Nor do I agree with intelligent design even in theology, for I think that evolution is more compatible with a belief in a loving God (because of the philosophical problem of evil)  Frankly, I consider design to be incompatible with the very essence of what life is 
DragonFly liked this post
Great post, Mitch 
I'm referring to "a lot is determinate", leaving room that some is indeterminate since QM finds this, and some brain doings may be at the micro-macro boundary and be affected, this degrading our ability to operate our intentions 
Here's a "libertarian" example/definition that may fit better:
“Hard Determinism and Libertarianism
Probing further into the free will-debate, we meet two different kinds of incompatibilist positions: hard determinism, which holds that determinism is true and that free will is not compatible with determinism, and libertarianism, which holds that we do have free will and that determinism is false  Given that these positions agree about the definition of determinism, we here actually have a genuine disagreement over fundamental ontological matters – a disagreement about whether determinism is true or not  This is a peculiar question to have strong disagreements about, however, since we know the final answer that we will ever get concerning the truth of determinism: that the state of the world is caused to be the way it is by its prior state at least to some degree, but to what degree exactly can never be known 
The libertarian position has often been criticized with the argument that even if determinism is not true, we still do not have free will, since our actions then simply are the product of a combination of deterministic and indeterministic events that we still do not ultimately choose ourselves, a view referred to as hard incompatibilism  Libertarians do not necessarily accept that this argument shows that we do not have free will, and the reason, or at least a big part of it, should not surprise anyone at this point: they simply define free will differently  According to libertarians, such as Robert Nozick and Robert Kane, one has free will if one could have acted otherwise than one did, and if indeterminism is true, then it may be true that we could have “acted” differently than we did under the exact same circumstances, and that we thereby might have free will in this sense  It should be pointed out, though, that critics of libertarianism are“rightly skeptical about the relevance of this kind of free will  First of all, the free will that libertarians endorse is, unlike what many libertarians seem to think, not an ethically relevant kind of freedom, and it does not have anything to do with the freedom of action that we by definition want  Second, the hard incompatibilist is right that no matter what is true about the degree to which the universe is deterministic, our actions are still caused by prior causes ultimately beyond our own control, which few of those who identify themselves as libertarians seem to want to acknowledge  And lastly, the fact that our actions are caused by causes ultimately beyond our own control does, if we truly appreciated, undermine our intuition of retributive justice, an intuition that libertarians generally seem to want to defend intellectually  So, as many have pointed out already, libertarians are simply on a failed mission 
Together with the want to defend retributive blame and punishment, what seems to be the main motivation for people who defend a libertarian notion of free will seems to be a fear of predeterminism, a fear of there being just one possible outcome from the present state of the universe, which would imply that we ultimately cannot do anything to cause a different outcome than the one possible  Libertarians and others with the same fear have artfully tried to make various models to help them overcome this fear, for instance so-called two-stage models that propose that our choices consist of an indeterministic stage of generation of possible actions, and then our non-random choice of one of them  (It should be noted, in relation to such models, that even if this is how our choices are made, our choice to choose one of these “alternative possibilities” will still be caused by prior causes that are ultimately completely beyond our own control  Nothing changes this fact, again because decision-making is the product of complex physical processes; it is not an uncaused event ) It is generally unclear what the purpose of such models is  Are they a hypotheses we should test? They do not seem to be  Generally, these models most of all seem like an attempt to make the world fit our preconceived intuitions, which most of all resembles pseudoscience 
Fortunately, there is plenty of relief available to the libertarians and other people who have this fear, and it does not involve any unscientific models – neither two-stage, three-stage, nor any other number of stages  The source of this relief is the simple earlier-mentioned fact that we can never know whether there is just one or infinitely many possible outcomes from the present state of the universe  This simple fact gives us all the relief we could ask for, because it reveals that there is no reason to be sure that there is just one possible outcome from the present state of the universe  And, to repeat an important point, we are then left with the conclusion that the only reasonable thing to do is to try to make the best impact we can in the world, which is true no matter whether there is just one possible outcome from the present state of the universe or not, since our actions still have consequences and therefore still matter even in a fully deterministic universe 
Some, especially libertarians, might want to object to the claim that we can never know whether determinism is true or not, and even claim that we in fact now know, or at least have good reasons to believe, that indeterminism is true  Here is neuroscientist Peter Tse expressing something along those lines: “Henceforth, I will accept the weight of evidence from modern physics, and assume ontological indeterminism to be the case ” (Tse, 2013, p  244)  Making this assumption is, however, to take a position on an unanswerable question  Again, rather than making strong claims about this question, we should stick to what we in fact know, namely that we do not know ”
Excerpt From: Magnus Vinding  “Free Will: An Examination of Human Freedom ” iBooks  https://itunes apple com/us/book/free-w     3363?mt=11
To extend the OP's implications of physical processes/causes dominating…
There are still real values in an existence with no ultimate purpose, this 'value' meaning good and bad valences and actions  It would be of great value to lessen suffering and improve well-being in humans and in all species  (Fixed wills are dynamic, simply meaning that they can learn and thus change to a better fixed will )
As for our model of reality, this is consciousness and it is ever our only view point inside the head in a brain, being what it is like to experience the world from the inside out 
by RJG on April 22nd, 2018, 1:07 am
Direct realism is not possible  We humans can only experience 'experiences' (sensations; sense data), not the 'real' things or objects themselves  Furthermore, we have no way of knowing if these experiences represent 'real' objects, or are just simply products of illusion; hallucination, delusion, dream, mirage, etc 
For this reason, solipsism is a possibility (i e  it is just as plausible as it is not), and true self-awareness is not possible (i e  we don't experience objects, including those called 'self')
DragonFly wrote: There is no direct (literal) view of the actual reality 'out there'  Our inner viewport is ever only that of the model (qualia) of inner and outer reality built by the brain  We see/sense nothing but this model made inside the brain 
Braininvat wrote: I invite anyone who thinks that bus hurtling down the street is nothing but a model in the brain to step in front of it 
Isn't it possible to dream or hallucinate stepping out in front of a bus hurtling down the street? This does not mean that the bus (in the dream/hallucination) is actually 'real' 
One does not normally step out in front of a bus (even in dreams) because they think it is not real, - it is the 'fear' (that it might be real, and) being smashed by it, that compels one not to step in front of it 
Braininvat wrote: Your impression of the bus may be indirect, but it has a direct causal chain of connections to the actual bus out there 
Not necessarily  You are assuming there is an "actual" bus out there (instead of a possible "hallucinated" bus)  We have no way of knowing the cause of our mental impressions 
by wolfhnd on April 22nd, 2018, 3:31 am
A bus that we do not step in front of is an extremely low resolution concept of what a bus is  Only the people who design and maintain the bus really know what a bus is at a relatively high resolution  Even then the designer doesn't really know the bus on the street because a bus is not just a collection of parts but takes it's meaning from an even more complex social and physical environment 
If you're a realist you assume that the bus can in theory be defined down to it's subatomic particles and a high resolution image of what it is can be created  The problem is that human perspective such an approach strips meaning from the image 
The other problem is that the kind of truth that a purely scientific approach provides tends to confuse the thing itself with it's mathematical model  The kind of absolutism that math provides is always subjective first because the parameters are always finite but the environment from our perspective is practically infinite and second because the model is an approximation even if 2+2 is always 4  A reductionist approach is a practical necessity that doesn't satisfy the evolutionary imperative for meaning 
The old view that everything can be reduced to cause and effect is itself challenged by the accepted view that determinism itself breaks down at tiny scales  Myself I'm not bothered by the indeterminate because I'm a pragmatist and close enough seems to satisfy practical solutions, scientific issues and philosophical questions  The philosophers goal is to determine what constitutes close enough to preserve life and meaning 
mitchellmckain wrote: If you are not acting according to your desire then this is an example of actions without free will 
If you act according to your desires, then you are it's slave  There is no free-will in slavery 
We don't control our desires  Our desires control us 
by DragonFly on April 22nd, 2018, 10:40 am
“This distinction between subject and object is not just an interesting oddity  It begins at the level of physics in the distinction between the probability inherent in symbolic measurements and the certainty of material laws  The distinction is later exemplified in the difference between a genotype, the sequence of nucleotide symbols that make up an organism’s DNA, and phenotype, its actual physical structure that those symbols prescribe  It travels with us up the evolutionary layers to the distinction between the mind and the brain ”
“These concepts will help us see how neural circuits are structures with a double life: they carry symbolic information, which is subject to arbitrary rules, yet they possess a material structure that is subject to the laws of physics ”
Excerpt From: Michael S  Gazzaniga  “The Consciousness Instinct ” iBooks  https://itunes apple com/us/book/the-co     3607?mt=11
by Neri on April 22nd, 2018, 11:13 am
On this topic, I should like to associate myself with the views of Mitch and BIV and will only add s few additional comments 
The question is not whether our experience is equivalent in every way to what lies outside of us, for such a thing is impossible 
[A perception cannot be exactly the same as a material object, for the former depends upon a sentient being for its existence, whereas the latter does not  Further, it is impossible to know everything that may be predicated of any material object by merely perceiving it ]
The real question is: Do sense impressions correspond to material objects in such a way that they are effective in preserving us from dangers that lie outside of us?
This question veritably answers itself  Only a madman would deny the evidence of his own senses 
It is essential to understand that the correspondence of which I speak depends on the reality of motion [from which we derive the ideas of time and space] 
To keep ourselves safe, it is necessary that we have the ability to know when a material object is moving closer or further from us and to be able to recognize an object as a danger  This, the senses give us, for perceptions like all other experiences are memories [are preserved over time] 
An object is recognized as a danger through prior sensory experiences preserved as long-term memories 
In order to be recognized and remembered as a danger, a material object must have the power to produce a particular human experience of it 
That power is part of the nature of the object and is thus truly reflected in the perception of it—even though there may be more to the object than its power to yield a human perception 
To the reasonable mind, the above comments may properly be seen as statements of the obvious  The curious fact, however, is that a whole school of western philosophy has labored mightily to deny the obvious 
I agree; I'm only delving into the inner experience to see how it works and what may become of that 
by TheVat on April 22nd, 2018, 11:57 am
RJG, this tablet ate the quoted part of your post and somehow hid the submit button, so sorry about the missing comment    
No, I was not assuming the in-the-moment knowledge, but rather that facts about buses are physically verifiable when science is applied  It is not difficult to verify that I was neither dreaming nor hallucinating  We are saved from solipsism by the multiplicity of observers and their reports  We can open a book and read complex prose (something that can't be done in dreams) that reveals areas of knowledge utterly unknown to us and beyond our previous experiences  We have senses enhanced by instruments that can show us photons leaving the photosphere of the sun and bouncing off solid objects like buses in particular and regular patterns, etc  Inner phenomenal reality and external reality are seamlessly connected and interacting - it is only big cranium apes like us who erect a wall of demarcation between them  Or drugs or pathological conditions that disrupt the causal connections 
To say that sensory data is incomplete is not equivalent to saying that it is deceptive  We are deceived only if we imagine that our impressions are complete  Our brains are engineered to find relevant data, not complete data  ("engineered" probably needs quotes)
by TheVat on April 22nd, 2018, 12:00 pm
Had to use Quick Reply window to post the above  Anyone else losing the submit button after Full Editor has been open for a couple minutes?? I will try to make sure this doesn't happen to anyone 
by DragonFly on April 22nd, 2018, 1:58 pm
What else, for now:
“Finally, affective consciousness—emotionally positive and negative feelings—has its own brain circuits, it does not require isomorphic mapping, and it may be experienced as mental states rather than mental images (figure 2 5B; chapters 7 and 8)  Thus, isomorphic maps are only one part of the creation and evolution of subjectivity and “something it is like to be”; many other special and general features (table 2 1) are required to create sensory consciousness and ontological subjectivity ”
“Consciousness-associated attention has several subtypes, including bottom-up (exogenous) versus top-down (endogenous) attention 48 Bottom-up attention is driven by the importance of the incoming stimuli and leads to the animal orienting to things that happen suddenly in the environment  Top-down attention, on the other hand, involves proactive anticipation, maintaining attention by concentration and focusing on goals 
Excerpt From: Todd E  Feinberg  “The Ancient Origins of Consciousness ” iBooks  https://itunes apple com/us/book/the-an     6953?mt=11
by RJG on April 22nd, 2018, 2:58 pm
Neri wrote: The real question is: Do sense impressions correspond to material objects in such a way that they are effective in preserving us from dangers that lie outside of us?
Firstly, we are not consciously aware of the actual causers (the supposed 'real' objects themselves) of these "sense impressions"  We are only consciously aware of the actual "sense impressions" (i e  the actual physical bodily reactions; experiences) themselves,    and of course this is only after they occur (after they impact our body) 
Secondly, we all assume that these "sense impressions" are the result of something 'real' out-there  Whether from a misfiring (hallucinating) brain, or from sensory signals emanating from a real object itself, it is still nonetheless 'real'  We all assume these "sense impressions" are the automatic reaction/response from some 'real' stimuli 
Thirdly, what "preserves us from danger" is NOT the conscious awareness of our sense impressions, but instead, it is the body's automatic RESPONSE to this danger (STIMULI) that "preserves us from danger",    and not the conscious awareness of said response 
Fourthly, if the body auto-responds in a particular way then the likelihood of survivability is enhanced, and if the response is otherwise then it may be diminished 
Neri wrote: To keep ourselves safe, it is necessary that we have the ability to know when a material object is moving closer or further from us and to be able to recognize an object as a danger 
Not so  It is NOT the "knowing" or "recognizing" of the dangerous moving object that "keep ourselves safe"  It is the body's automatic reaction/response to this moving object (stimuli) that "keep ourselves safe" 
Remember, we can only be conscious of (i e  know or recognize) actual bodily reactions/events, and not of other 'external' events  We don't consciously know/recognize how we responded until 'after' we (our body) responds  Our consciousness (knowing/recognizing) is wholly dependent upon our bodily reactions/responses,    NOT the other way around 
Without something (e g  sense impressions; bodily reactions) to be conscious of, then there is no consciousness (   no knowing or recognizing!) 
Braininvat wrote: No, I was not assuming the in-the-moment knowledge, but rather that facts about buses are physically verifiable when science is applied 
Can't one hallucinate they are doing verifiable science?
Braininvat wrote: It is not difficult to verify that I was neither dreaming nor hallucinating   
   We can open a book and read complex prose (something that can't be done in dreams) that reveals areas of knowledge utterly unknown to us and beyond our previous experiences 
I'm not so confident/convinced of this  Have you seen the movie "A Beautiful Mind"?    or have had family members with mental issues?
Braininvat wrote: We are saved from solipsism by the multiplicity of observers and their reports   
   We have senses enhanced by instruments that can show us photons leaving the photosphere of the sun and bouncing off solid objects like buses in particular and regular patterns, etc  Inner phenomenal reality and external reality are seamlessly connected and interacting - it is only big cranium apes like us who erect a wall of demarcation between them 
Isn't it possible to hallucinate these "multiple observers and their reports",    and their "instrumentation" results?
Other than by 'blind faith', how can one really know that their perceptions are the 'true' representations of reality?    I think it is not possible,    I think we can only 'hope' that our personal view is of reality itself 
We can't perceive beyond our current ("suspect") perceptions 
How about that the 'knowing' is done by the brain that built the qualia showing the danger, for the brain thus already has the information available, in whatever form it uses to 'know' 
by TheVat on April 22nd, 2018, 4:50 pm
Isnt it possible to hallucinate these "multiple observers and their reports",    and their "instrumentation" results?
- RJG
For me, that level of arch-skepticism is an epistemic doldrums zone  As David Hume famously observed about a conference on epistemology on Europe, "on finishing their discussion, the participants all departed by means of the doors  " (or similar; don't have exact quote handy ATM)
Whenever I write numbers in dreams they change as I write them and when I read it often fills up with garbage 
I've been lucidly inspecting my dreams  Some flaws are that bugs appear as triangles  Yesterday, I was going to eat in a cafeteria but you had to bring your own plates from home, so I already suspected something  I did find a pile of plates and took one, but I was soon somehow holding the whole pile, which then happened again and again, so, as in these stuck cases, I clench my whole body and that wakes me up  Other times, for lesser problems or to be sure of the dream state, I am able to open one eye and see the window and then go back to the dream  And sometimes the dream perfectly shows an entire scene in fabulous detail, such as a mid summer dusk, with even those whirly things floating through the air 
by mitchellmckain on April 23rd, 2018, 4:00 am
DragonFly » April 20th, 2018, 2:14 pm wrote: The model seems to be super real,
To me, that seems like a completely nonsensical thing to say to  "Seems real" compared to what? By the only standard we have, it is real, for it is the only standard which we have for making such a measurement  What you say is practically Platonic in the implied imagination of some greater reality somewhere else 
DragonFly » April 20th, 2018, 2:14 pm wrote: So, in sum so far, direct realism is an illusion, but is a very useful illusion, which we might better call a fine representation by the model, since the word 'illusion' is more about what's wrong as not really showing its object as substantial and really being behind it 
In philosophy of mind, naïve realism, also known as direct realism or common sense realism, is the idea that the senses provide us with direct awareness of objects as they really are  Objects obey the laws of physics and retain all their properties whether or not there is anyone to observe them [1] They are composed of matter, occupy space and have properties, such as size, shape, texture, smell, taste and colour, that are usually perceived correctly 
In contrast, some forms of idealism claim that no world exists apart from mind-dependent ideas, and some forms of skepticism say we cannot trust our senses  Naïve realism is known as direct as against indirect or representative realism when its arguments are developed to counter the latter position, also known as epistemological dualism;[2] that our conscious experience is not of the real world but of an internal representation of the world 
There is nothing of illusion in direct realism  There is only the foolish rhetoric implying that "direct" in "direct realism" means absorbing the actual object rather than data from those objects  The data IS from actual objects and does provide awareness of actual objects obeying the laws of physics  The implication that anyone is confusing the awareness of an object with the object itself is just ridiculous  Instead you can say that the process of perception is what makes illusions possible  Because we are interpreting data, then it is entirely possible for similar data to suggest something other than what is the case, such as the impression of water from a mirage -- at least until we learn the distinctions 
When you consider the philosophical alternative, plastering the word "illusion" on direct realism implies that idealism is the reality beneath it  And that is an implication I would refute most heatedly  As for indirect realism, as I explained above, I think it is carrying things too far to say that we are experiencing the model instead of reality  Instead I would limits the validity only to the idea that we use a model in the process of perception  In that sense you could say my position is in-between that of direct realism and indirect realism 
DragonFly » April 20th, 2018, 2:14 pm wrote: Dreams, then, would be better called illusions; further they demonstrate the power of the structure of the model  When we inspects objects in dreams they look just as good as when we see them awake, although backgrounds come and go inconsistently and there are narrative gaps (all of a sudden we are driving a vehicle without ever having gotten into it, plus the controls are a mystery )
I think it is unwise to make generalizations about dreams in such a manner  That is not my experience of dreams at all  My impression is that dreams consist of a mental (linguistic) narrative using memory to fill in the details  The only uniqueness in such experiences are the irrational combinations and discontinuities  Because of this, I have no sense this is anywhere near as good as when we see things awake, when we are interpreting fresh new sensory data  For me, this imparts a considerably dim character to the dream experience 
For me dreams are rather comparable to when I envision scenarios for my books  I see them in my mind's eye but not in a manner that is remotely comparable to my experience of reality through the senses  I am not suggesting that everyone experiences dreams this way  On the contrary, the phenomenon of schizophrenia suggests to me that some people can see things in their minds eye with the same vividness of the senses, for otherwise, how can they not know the difference?
DragonFly » April 20th, 2018, 2:14 pm wrote: Another illusion is the feeling of having all of the information in a qualia scene as instantly available, as well as feeling that it is all happening in real time, plus that one is directing it all right then and there 
Calling this illusion is a gross exaggeration  At most it is simply approximation 
by DragonFly on April 23rd, 2018, 11:37 am
'Imagination' (say, of things to happen in a book,) uses the model, too, but the scenes are about 90% transparent, probably so they don't get in the way of the real scenes about 
by DragonFly on April 23rd, 2018, 2:51 pm
Boggling idea of the Subject/Object Cut…
“The Schnitt and the Origins of Life
Physicists refer to the inescapable separation of a subject (the measurer) from an object (the measured) as die Schnitt  (What a great word!) Pattee calls “this unavoidable conceptual separation of the knower and the known, or the symbolic record of an event and the event itself, the epistemic cut 
There is a world of actions that exists on the side of the observer with the observer’s record of an event  There is also a separate world of actions on the side of the event itself  This sounds confusing, but think of the explanatory gap between your subjective experience of an event (I had so much fun body-surfing) and the event itself (A person went swimming in the ocean)  Alternately, you can think of the explanatory gap between the same subjective experience (This is fun) and the goings-on within the brain (Some neurons fired while a person was swimming in the ocean)  These are all just versions of the subject/object complementarity seen in physics  Here is the really wild part: Who’s measuring the events? To examine the difference between a person’s subjective experience and objective reality, do we need a scientist? Who’s measuring the scientist?
Pattee points out that neither classical nor quantum theory formally defines the subject, that is, the agent or observer that determines what is measured  Physics, therefore, does not say where to make the epistemic cut 4 Quantum measurement does not need a physicist-observer, however  Pattee argues that other things can perform quantum measurements  For example, enzymes (such as DNA polymerases) can act as measurement agents, performing quantum measurement during a cell’s replication process  No human observer is needed 
For Schrödinger, the joke was on us  He was trying to point out that there is something missing in our understanding  Pattee got it (in high school) and buckled down to attack the problem  Where should we put the cut, the gap, die Schnitt? With his consuming interest in the origins of life, he came to realize that human consciousness was way too high a layer in the architecture of all living organisms to put the epistemic cut between the observer and the observed, between the subjective experience and the event itself  There are umpteen layers between subatomic particles and human brains  There are plenty of layers between subatomic particles and brains in general (cat or mouse or fly or worm)  Putting the major epistemic cut that high led to the nonsense of Schrödinger’s cat existing as a quantum system  There was no pussyfooting around for Pattee: “I have taken the point of view that the question of what constitutes an observation in quantum mechanics must arise long before we reach the complexity of the brain  In fact, I propose … that the gap between quantum and classical behavior is inherent in the distinction between inanimate and living matter 
There you have it  Pattee proposes that the gap resulted from a process equivalent to quantum measurement that began with self-replication at the origin of life with the cell as the simplest agent  The epistemic cut, the subject/object cut, the mind/matter cut, all are rooted to that original cut at the origin of life  The gap between subjective feeling and objective neural firings didn’t come about with the appearance of brains  It was already there when the first cell started living  Two complementary modes of behavior, two levels of description are inherent in life itself, were present at the origin of life, have been conserved by evolution, and continue to be necessary for differentiating subjective experience from the event itself  That is a mind-boggling idea ”
by mitchellmckain on April 24th, 2018, 1:06 pm
The "like" on the above post is not to be construed as complete agreement with conclusions, but rather more with an abundant approval of the questions and issues raised 
DragonFly » April 23rd, 2018, 1:51 pm wrote: Boggling idea of the Subject/Object Cut…
Absolute agreement here! I have always considered quantum interpretations linking quantum decoherence with human consciousness to be absurd -- with one exception  The one interpretation which makes this link and is not absurd is the Everett Interpretation  THOUGH, I would not count this in its favor! Furthermore, it isn't actually necessary to the Everett Interpretation, for it is quite possible to shift the locus of the decoherence in this interpetation to agree with other interpretations 
DragonFly » April 23rd, 2018, 1:51 pm wrote: For Schrödinger, the joke was on us  He was trying to point out that there is something missing in our understanding 
Agreed! That is how I have always understood the Schrödinger cat thought experiment  It was not to seriously propose the existence of dead-alive cats but to highlight the absurdities which come from the way that quantum physics was usually being presented 
DragonFly » April 23rd, 2018, 1:51 pm wrote: Pattee got it (in high school) and buckled down to attack the problem  Where should we put the cut, the gap, die Schnitt? With his consuming interest in the origins of life, he came to realize that human consciousness was way too high a layer in the architecture of all living organisms to put the epistemic cut between the observer and the observed, between the subjective experience and the event itself  There are umpteen layers between subatomic particles and human brains  There are plenty of layers between subatomic particles and brains in general (cat or mouse or fly or worm)  Putting the major epistemic cut that high led to the nonsense of Schrödinger’s cat existing as a quantum system  There was no pussyfooting around for Pattee: “I have taken the point of view that the question of what constitutes an observation in quantum mechanics must arise long before we reach the complexity of the brain  In fact, I propose … that the gap between quantum and classical behavior is inherent in the distinction between inanimate and living matter 
And here is where we have a disagreement  While I totally appreciate pushing many things such as consciousness, learning, and creativity down to the lowest levels of the divide between the living and nonliving, I personally do not believe that this has anything whatsoever to do with the quantum measurement problem 
DragonFly » April 23rd, 2018, 1:51 pm wrote: There you have it  Pattee proposes that the gap resulted from a process equivalent to quantum measurement that began with self-replication at the origin of life with the cell as the simplest agent 
Furthermore, I think this focus on self-replication as the divide between the living and non-living may be a little behind the times  Metabolism first theories of abiogenesis and the study of prebiotic evolution strongly suggest that key features of the life process are located way before the development of self-replicating molecules such as RNA and DNA  On the other hand, perhaps this idea of self-replication can be extended to processes in prebiotic evolution in which there is a catalysis of chemical reactions which replenish the chemical components  After all, self-maintenance is a definitive feature of the life process and would suggest that any life process must include the regeneration of its components 
DragonFly » April 23rd, 2018, 1:51 pm wrote: The epistemic cut, the subject/object cut, the mind/matter cut, all are rooted to that original cut at the origin of life  The gap between subjective feeling and objective neural firings didn’t come about with the appearance of brains  It was already there when the first cell started living  Two complementary modes of behavior, two levels of description are inherent in life itself, were present at the origin of life, have been conserved by evolution, and continue to be necessary for differentiating subjective experience from the event itself  That is a mind-boggling idea ”
This would only work if you can make a logical connection with this definitive feature of life in a process of self maintenance  I have already suggested a connection between this and consciousness by pointing out that self maintenance requires some kind of awareness of self, both as it is and as it "should be " Without some sort of "should be" in some form there can be no self-maintenance  It should be noted that there are numerous quantitative features to this, such as the clarity with which this goal of self as it "should be" is represented, the determination/flexibility with which it is adhered to (or in other words the range of circumstances which can be handled in holding to this goal) 
by TheVat on April 24th, 2018, 1:52 pm
It seems likely a paramecium does no representing to a self, and is pretty much a cellular machine lacking sentience 
A paramecium is not full of Schnitt  It is not measuring or having goals or anything else  It is an automaton  To think otherwise would be to invite some sort of Bergsonian "elan vital" or other dualistic essence 
The problem with the term "observation" is that it's prejudicial in common parlance  It implies some sort of sentient observer  It implies a subjective aspect  So a more neutral term would be needed when a microbe registers a chance in its environment and contracts or expands or fires up the cilia or dumps the vacuoles or whatever  Or when a Bose Einstein condensate loses its coherence in a wet noisy puddle 
Braininvat » April 24th, 2018, 12:52 pm wrote: It seems likely a paramecium does no representing to a self, and is pretty much a cellular machine lacking sentience 
But it is not a machine for the simple reason that it is not a product of design  The only reasons for which it does things are its own reasons  It is a product of self organization, and the learning process which is evolution 
I certainly agree with the term "biological machinery," which is to say that there is no reason to distinguish things simply on the basis that one uses the interactions of organic chemistry  Thus I think the locus of difference between the living organism and the machine has to do with origins whether it is by design or by learning, evolution, and self-organization 
Braininvat » April 24th, 2018, 12:52 pm wrote: The problem with the term "observation" is that it's prejudicial in common parlance  It implies some sort of sentient observer  It implies a subjective aspect  So a more neutral term would be needed when a microbe registers a chance in its environment and contracts or expands or fires up the cilia or dumps the vacuoles or whatever 
But the problem with this is that the prejudice in language goes both ways with the presumption of an uncrossable divide between the sentient and the non-sentient, when all the evidence points to a continuum going all the way from the non-living to the living to the sentient  And this is not a linear continuum but a rapidly branching tree with many capabilities somewhat arbitrarily (or rather anthropomorphically) lumped into this term "sentience "
Context 2: \section{introduction}
In the past few years, the synthesis of ferromagnetic semiconductors has become a major challenge for spintronics  Actually, growing a magnetic and semiconducting material could lead to promising advances like spin injection into non magnetic semiconductors, or electrical manipulation of carrier induced magnetism in magnetic semiconductors \cite{ohno00,Bouk02}  Up to now, major efforts have focused on diluted magnetic semiconductors (DMS) in which the host semiconducting matrix is randomly substituted by transition metal (TM) ions such as Mn, Cr, Ni, Fe or Co \cite{Diet02}  However Curie temperatures ($T_{C}$) in DMS remain rather low and TM concentrations must be drastically raised in order to increase $T_{C}$ up to room temperature  That usually leads to phase separation and the formation of secondary phases  It was recently shown that phase separation induced by spinodal decomposition could lead to a significant increase of $T_{C}$ \cite{Diet06,Fuku06}  For semiconductors showing $T_{C}$ higher than room temperature one can foresee the fabrication of nanodevices such as memory nanodots, or nanochannels for spin injection  Therefore, the precise control of inhomogeneities appears as a new challenge which may open a way to industrial applications of ferromagnetism in semiconductors 

The increasing interest in group-IV magnetic semiconductors can also be explained by their potential compatibility with the existing silicon technology  In 2002, carrier mediated ferromagnetism was reported in  MBE grown Ge$_{0 94}$Mn$_{0 06}$ films by Park \textit{et al } \cite{Park02}  The maximum critical temperature was 116 K  Recently many publications indicate a significant increase of $T_{C}$ in Ge$_{1-x}$Mn$_{x}$ material depending on growth conditions \cite{Pint05,Li05,tsui03}  Cho \textit{et al } reported a Curie temperature as high as 285 K \cite{Cho02}  
Taking into account the strong tendency of Mn ions to form intermetallic compounds in germanium, a detailed investigation of the nanoscale structure is required  Up to now, only a few studies have focused on the nanoscale composition in Ge$_{1-x}$Mn$_{x}$ films  Local chemical inhomogeneities have been recently reported by Kang \textit{et al } \cite{Kang05} who evidenced a micrometer scale segregation of manganese in large Mn rich stripes  Ge$_3$Mn$_5$ as well as Ge$_8$Mn$_{11}$ clusters embedded in a germanium matrix have been reported by many authors  However, Curie temperatures never exceed 300 K \cite{Bihl06,Morr06,Pass06,Ahle06}  Ge$_3$Mn$_5$ clusters exhibit a Curie temperature of 296 K \cite{Mass90}  This phase frequently observed in Ge$_{1-x}$Mn$_{x}$ films is the most stable (Ge,Mn) alloy  The other stable compound Ge$_8$Mn$_{11}$ has also been observed in nanocrystallites surrounded with pure germanium \cite{Park01}  Ge$_8$Mn$_{11}$ and Ge$_3$Mn$_5$ phases are ferromagnetic but their metallic character considerably complicates their potential use as spin injectors 
Recently, some new Mn-rich nanostructures have been evidenced in Ge$_{1-x}$Mn$_{x}$ layers  Sugahara \textit{et al } \cite{Sugh05} reported the formation of high Mn content (between 10 \% and 20 \% of Mn) amorphous Ge$_{1-x}$Mn$_x$ precipitates  in a Mn-free germanium matrix  Mn-rich coherent cubic clusters were observed by Ahlers \textit{et al } \cite{Ahle06} which exhibit a Curie temperatures below 200 K  Finally, high-$T_{C}$ ($>$ 400 K) Mn-rich nanocolumns have been evidenced \cite{Jame06} which could lead to silicon compatible room temperature operational devices \\
In the present paper, we investigate the structural and magnetic properties of Ge$_{1-x}$Mn$_x$ thin films for low growth temperatures ($<$ 200$^{\circ}$C) and low Mn concentrations (between 1 \% and 11 \%)  By combining TEM, x-Ray diffraction and SQUID magnetometry, we could identify different magnetic phases  We show that depending on growth conditions, we obtain either Mn-rich nanocolumns or Ge$_{3}$Mn$_{5}$ clusters embedded in a germanium matrix  We discuss the structural and magnetic properties of these nanostructures as a function of manganese concentration and growth temperature  We also discuss the magnetic anisotropy of nanocolumns and  
Ge$_3$Mn$_5$ clusters  

\section{Sample growth}

Growth was performed using solid sources molecular beam epitaxy (MBE) by co-depositing Ge and Mn evaporated from standard Knudsen effusion cells   Deposition rate was low ($\approx$ 0 2 \AA s$^{-1}$)  Germanium substrates were epi-ready Ge(001) wafers with a residual n-type doping and resistivity of 10$^{15}$ cm$^{-3}$ and 5 $\Omega cm$ respectively  After thermal desorption of the surface oxide, a 40 nm thick Ge buffer layer was grown at 250$^{\circ}$C, resulting in a 2 $\times$ 1 surface reconstruction as observed by reflection high energy electron diffraction (RHEED) (see Fig  1a)  Next, 80 nm thick Ge$_{1-x}$Mn$_{x}$ films were subsequently grown  at low substrate temperature (from 80$^{\circ}$C to 200$^{\circ}$C)  Mn content has been determined by x-ray fluorescence measurements performed on thick samples ($\approx$ 1 $\mu m$ thick) and complementary Rutherford Back Scattering (RBS) on thin Ge$_{1-x}$Mn$_{x}$ films grown on silicon  Mn concentrations range from 1 \% to 11\% Mn 

For Ge$_{1-x}$Mn$_{x}$ films grown at substrate temperatures below 180$^{\circ}$C, after the first monolayer (ML) deposition, the  2 $\times$ 1 surface reconstruction almost totally disappears  After depositing few MLs, a slightly diffuse 1 $\times$ 1 streaky RHEED pattern and a very weak 2 $\times$ 1 reconstruction (Fig  1b) indicate a predominantly two-dimensional growth  For growth temperatures above 180$^{\circ}$C additional spots appear in the RHEED pattern during the Ge$_{1-x}$Mn$_{x}$ growth (Fig  1c)  These spots may correspond to the formation of very small secondary phase crystallites  The nature of these crystallites will be discussed below 

Transmission electron microscopy (TEM) observations were performed using a JEOL 4000EX microscope with an acceleration voltage of 400 kV  Energy filtered transmission electron microscopy (EFTEM) was done using a JEOL 3010 microscope equipped with a Gatan Image Filter   Sample preparation was carried out by standard mechanical polishing and argon ion milling for cross-section investigations and plane views were prepared by wet etching with H$_3$PO$_4$-H$_2$O$_2$ solution \cite{Kaga82} 

\begin{figure}[htb]
    \center
    \includegraphics[width= 29\linewidth]{ /fig1a eps}
    \includegraphics[width= 29\linewidth]{ /fig1b eps}
    \includegraphics[width= 29\linewidth]{ /fig1c eps}
    \caption{RHEED patterns recorded during the growth of Ge$_{1-x}$Mn$_{x}$ films: (a) 2 $\times$ 1 surface reconstruction of the germanium buffer layer  (b) 1 $\times$ 1 streaky RHEED pattern obtained at low growth temperatures ($T_g<$180$^{\circ}$C)  (c) RHEED pattern of a sample grown at $T_g=$180$^{\circ}$C  The additional spots reveal the presence of Ge$_3$Mn$_5$ clusters at the surface of the film }
\label{fig1}
\end{figure}

\section{Structural properties \label{structural}}

\begin{figure}[htb]
    \center
	\includegraphics[width= 49\linewidth]{ /fig2a eps}
	\includegraphics[width= 49\linewidth]{ /fig2b eps}
	 \includegraphics[width= 49\linewidth]{ /fig2c eps}
	 \includegraphics[width= 49\linewidth]{ /fig2d eps}
    \caption{Transmission electron micrographs of a Ge$_{1-x}$Mn$_{x}$ film grown at 130$^{\circ}$C and containing 6 \% of manganese  (a) cross-section along the [110] axis : we clearly see the presence of nanocolumns elongated along the growth axis  (b) High resolution image of the interface between the Ge$_{1-x}$Mn$_{x}$ film and the Ge buffer layer  The Ge$_{1-x}$Mn$_{x}$ film exhibits the same diamond structure as pure germanium  No defect can be seen which could be caused by the presence of nanocolumns  (c) Plane view micrograph performed on the same sample confirms the columnar structure and gives the density and size distribution of nanocolumns  (d) Mn chemical map obtained by energy filtered transmission electron microcopy (EFTEM)  The background was carefully substracted from pre-edge images  Bright areas correspond to Mn-rich regions }
\label{fig2}
\end{figure}

In samples grown at 130$^{\circ}$C and containing 6 \% Mn, we can observe vertical elongated nanostructures \textit{i e } nanocolumns as shown in Fig  2a  Nanocolumns extend through the whole Ge$_{1-x}$Mn$_{x}$ film thickness  From the high resolution TEM image shown in Fig  2b, we deduce their average diameter around 3 nm  Moreover in Fig  2b, the interface between the Ge buffer layer and the Ge$_{1-x}$Mn$_{x}$ film is flat and no defect propagates from the interface into the film  The Ge$_{1-x}$Mn$_{x}$ film is a perfect single crystal in epitaxial relationship with the substrate  In Fig  2c is shown a plane view micrograph of the same sample confirming the presence of nanocolumns in the film  From this image, we can deduce the size and density of nanocolumns  The nanocolumns density is 13000 $\rm{\mu m}^{-2}$ with a mean diameter of 3 nm which is coherent with cross-section measurements  In order to estimate the chemical composition of these nanocolumns, we further performed chemical mapping using EFTEM  In Fig  2d we show a cross sectional Mn chemical map of the Ge$_{1-x}$Mn$_{x}$ film  This map shows that the formation of nanocolumns is a consequence of Mn segregation  Nanocolumns are Mn rich and the surrounding matrix is Mn poor  However, it is impossible to deduce the Mn concentration in Ge$_{1-x}$Mn$_{x}$ nanocolumns from this cross section  Indeed, in cross section observations, the columns diameter is much smaller than the probed film thickness and the signal comes from the superposititon of the Ge matrix and Mn-rich nanocolumns  In order to quantify Mn concentration inside the nanocolumns and inside the Ge matrix, EELS measurements (not shown here) have been performed in a plane view geometry \cite{Jame06}  These observations revealed that the matrix Mn content is below 1 \% (detection limit of our instrument)  Measuring the surface occupied by the matrix and the nanocolumns in plane view TEM images, and considering the average Mn concentration in the sample (6 \%), we can estimate the Mn concentration in the nanocolumns  The Mn concentration measured by EELS being between 0\% and 1\%, we can conclude that the Mn content in the nanocolumns is between 30 \% and 38 \% \\
For samples grown between 80$^\circ$C and 150$^\circ$C cross section and plane view TEM observations reveal the presence of Mn rich nanocolumns surrounded with a Mn poor Ge matrix  In order to investigate the influence of Mn concentration on the structural properties of Ge$_{1-x}$Mn$_{x}$ films, ten samples have been grown at 100$^\circ$C and at 150$^\circ$C with Mn concentrations of 1 3 \%, 2 3 \%, 4 \%, 7 \% and 11 3 \%  Their structural properties have been investigated by plane view TEM observations  

\begin{figure}[htb]
    \center
    \includegraphics[width= 98\linewidth]{ /fig3a eps}
	\includegraphics[width= 45\linewidth]{ /fig3b eps}
		\includegraphics[width= 45\linewidth]{ /fig3c eps}
    \caption{Nanocolumns size and density as a function of growth conditions  Samples considered have been grown at 100$^{\circ}$C and 150$^{\circ}$C respectively  (a) Mn concentration dependence of the size distribution  (b) columns density as a function of Mn concentration  (c) Volume fraction of the nanocolumns as a function of Mn concentration }
 \label{fig3}
\end{figure}

For samples grown at 100$^\circ$C with Mn concentrations below 5 \% the nanocolumns mean diameter is 1 8$\pm$0 2 nm  The evolution of columns density as a fonction of Mn concentration is reported in figure 3b  By increasing the Mn concentration from 1 3 \% to 4 \% we observe a significant increase of the columns density from 13000 to 30000 $\rm{\mu m}^{-2}$  For Mn concentrations higher than 5 \% the density seems to reach a plateau corresponding to 35000 $\rm{\mu m}^{-2}$ and their diameter slightly increases from 1 8 nm at 4 \% to 2 8 nm at 11 3 \%  By plotting the volume fraction occupied by the columns in the film as a function of Mn concentration, we observe a linear dependence for Mn contents below 5 \%  The non-linear behavior above 5 \% may indicate that the mechanism of Mn incorporation is different in this concentration range, leading to an increase of Mn concentration in the columns or in the matrix  For samples grown at 100$^\circ$C, nanocolumns are always fully coherent with the surrounding matrix (Fig  4a)  

Increasing the Mn content in the samples grown at 150$^\circ$C from 1 3 \% to 11 3 \% leads to a decrease of the columns density (fig 3b)  Moreover, their average diameter increases significantly and size distributions become very broad (see Fig  3a)  For the highest Mn concentration (11 3 \%) we observe the coexistence of very small columns with a diameter of 2 5 nm and very large columns with a diameter of 9 nm  In samples grown at 150$^\circ$C containing 11 3 \% of Mn, the crystalline structure of nanocolumns is also highly modified  In plane view TEM micrographs, one can see columns exhibiting several different crystalline structures  We still observe some columns which are fully coherent with the Ge matrix like in the samples grown at lower temperature  Nevertheless, observations performed on these samples grown at 150$^\circ$C and with 11 3\% Mn reveal some uniaxially \cite{Jame06} or fully relaxed columns exhibiting a misfit of 4 \% between the matrix and the columns and leading to misfit dislocations at the interface between the column and the matrix (see fig  4b)  Thus we can conclude that coherent columns are probably in strong compression and the surrounding matrix in tension  On the same samples (T$_g$=150$^{\circ}$C, 11 3\% Mn), we also observe a large number of highly disordered nanocolumns leading to an amorphous like TEM contrast(fig  4c) 

\begin{figure}[htb]
    \center
   \includegraphics[width= 31\linewidth]{ /fig4a eps}
	\includegraphics[width= 31\linewidth]{ /fig4b eps}
	\includegraphics[width= 31\linewidth]{ /fig4c eps}
    \caption{Plane view high resolution transmission electron micrographs of different types of nanocolumns : (a) typical structure of a column grown at 100$^{\circ}$C  The crystal structure is exactly the same as germanium   (b) Partially relaxed nanocolumn  One can see dislocations at the interface between the columns and the matrix leading to stress relaxation  (c) Amorphous nanocolumn  These columns are typical in samples grown at 150$^{\circ}$C with high Mn contents }
 \label{fig4}
\end{figure}

In conclusion, we have evidenced a complex mechanism of Mn incorporation in Mn doped Ge films grown at low temperature  In particular Mn incorporation is highly inhomogeneous  For very low growth temperatures (below 120$^\circ$C) the diffusion of Mn atoms leads to the formation of Mn rich, vertical nanocolumns  Their density mostly depends on Mn concentration and their mean diameter is about 2 nm  These results can be compared with the theoretical predictions of Fukushima \textit{et al } \cite{Fuku06}: they proposed a model of spinodal decomposition in (Ga,Mn)N and (Zn,Cr)Te based on layer by layer growth conditions and a strong pair attraction between Mn atoms which leads to the formation of nanocolumns  This model may also properly describe the formation of Mn rich nanocolumns in our samples  Layer by layer growth conditions can be deduced from RHEED pattern evolution during growth  For all the samples grown at low temperature, RHEED observations clearly indicate two-dimensional growth  Moreover, Ge/Ge$_{1-x}$Mn$_{x}$/Ge heterostructures have been grown and observed by TEM (see Fig  5)  Ge$_{1-x}$Mn$_{x}$/Ge (as well as Ge/Ge$_{1-x}$Mn$_{x}$) interfaces are very flat and sharp thus confirming a two-dimensional, layer by layer growth mode  Therefore we can assume that the formation of Mn rich nanocolumns is a consequence of 2D-spinodal decomposition 

\begin{figure}[htb]
    \center
	\includegraphics[width= 7\linewidth]{ /fig5 eps}
    \caption{Cross section high resolution micrograph of a Ge/Ge$_{1-x}$Mn$_{x}$/Ge/Ge$_{1-x}$Mn$_{x}$/Ge heterostructure  This sample has been grown at 130 $^{\circ}$C with 6\% Mn  Ge$_{1-x}$Mn$_{x}$ layers are 15 nm thick and Ge spacers 5 nm thick  We clearly see the sharpness of both Ge$_{1-x}$Mn$_{x}$/Ge and Ge/Ge$_{1-x}$Mn$_{x}$ interfaces  Mn segregation leading to the columns formation already takes place in very thin Ge$_{1-x}$Mn$_{x}$ films }
\label{fig5}
\end{figure}

For growth temperatures higher than 160$^\circ$C, cross section TEM and EFTEM observations (not shown here) reveal the coexistence of two Mn-rich phases: nanocolumns and Ge$_{3}$Mn$_{5}$ nanoclusters embedded in the germanium matrix  A typical high resolution TEM image is shown in figure 6  
Ge$_{3}$Mn$_{5}$ clusters are not visible in RHEED patterns for temperatures below 180$^\circ$C  To investigate the nature of these clusters, we performed x-ray diffraction in $\theta-2\theta$ mode  Diffraction scans were acquired on a high resolution diffractometer using the copper K$_\alpha$ radiation and on the GMT station of the BM32 beamline at the European Synchrotron Radiation Facility (ESRF)  Three samples grown at different temperatures and/or annealed at high temperature were investigated  The two first samples are Ge$_{1-x}$Mn$_{x}$ films grown at 130$^\circ$C and 170$^\circ$C respectively  The third one has been grown at 130$^\circ$C and post-growth annealed at 650$^\circ$C  By analysing x-ray diffraction spectra, we can evidence two different crystalline structures  For the sample grown at 130$^\circ$C, the $\theta-2\theta$ scan only reveals the (004) Bragg peak of the germanium crystal, confirming the good epitaxial relationship between the layer and the substrate, and the absence of secondary phases in the film in spite of a high dynamics of the order of 10$^7$  For both samples grown at 170$^\circ$C and annealed at 650$^\circ$C, $\theta-2\theta$ spectra are identical  In addition to the (004) peak of germanium, we observe three additional weak peaks  The first one corresponds to the (002) germanium forbidden peak which probably comes from a small distortion of the germanium crystal, and the two other peaks are respectively attributed to the (002) and (004) Bragg peaks of a secondary phase  The $c$ lattice parameter of Ge$_3$Mn$_5$ hexagonal crystal is 5 053 \AA \ \cite{Fort90} which is in very good agreement with the values obtained from diffraction data for both (002) and (004) lines assuming that the $c$ axis of Ge$_3$Mn$_5$ is along the [001] direction of the Ge substrate 

\begin{figure}[htb]
    \center
	\includegraphics[width= 7\linewidth]{ /fig6 eps}
	\caption{Cross section high resolution transmission electron micrograph of a sample grown at 170$^{\circ}$C  We observe the coexistence of two different Mn-rich phases: Ge$_{1-x}$Mn$_{x}$ nanocolumns and Ge$_3$Mn$_5$ clusters }
\label{fig6}
\end{figure}

In summary, in a wide range of growth temperatures and Mn concentrations, we have evidenced a two-dimensional spinodal decomposition leading to the formation of Mn-rich nanocolumns in Ge$_{1-x}$Mn$_{x}$ films  This decomposition is probably the consequence of: $(i)$ a strong pair attraction between Mn atoms, $(ii)$ a strong surface diffusion of Mn atoms in germanium even at low growth temperatures and $(iii)$ layer by layer growth conditions  We have also investigated the influence of growth parameters on the spinodal decomposition: at low growth temperatures (100$^{\circ}$C), increasing the Mn content leads to higher columns densities while at higher growth temperatures (150$^{\circ}$C), the columns density remains nearly constant whereas their size increases drastically  By plotting the nanocolumns density as a function of Mn content, we have shown that the mechanism of Mn incorporation in Ge changes above 5 \% of Mn  Finally, using TEM observations and x-ray diffraction, we have shown that Ge$_3$Mn$_5$ nanoclusters start to form at growth temperatures higher than 160$^\circ$C 

\section{Magnetic properties \label{magnetic}}

We have thoroughly investigated the magnetic properties of thin Ge$_{1-x}$Mn$_{x}$ films for different growth temperatures and Mn concentrations  In this section, we focus on Mn concentrations between 2 \% and 11 \%  We could clearly identify four different magnetic phases in Ge$_{1-x}$Mn$_{x}$ films : diluted Mn atoms in the germanium matrix, low $T_{C}$ nanocolumns ($T_{C}$ $\leq$ 170 K), high $T_{C}$ nanocolumns ($T_{C}$ $\geq$ 400 K) and Ge$_{3}$Mn$_{5}$ clusters ($T_{C}$ $\thickapprox$ 300 K)  The relative weight of each phase clearly depends on the growth temperature and to a lesser extend on Mn concentration  For low growth temperature ($<$ 120$^{\circ}$C), we show that nanocolumns are actually made of four uncorrelated superparamagnetic nanostructures  Increasing T$_{g}$ above 120$^{\circ}$C, we first obtain continuous columns exhibiting low $T_{C}$ ($<$ 170 K) and high $T_{C}$ ($>$ 400 K) for $T_{g}\approx$130$^{\circ}$C  The larger columns become ferromagnetic \textit{i e } $T_{B}>T_{C}$  Meanwhile Ge$_{3}$Mn$_{5}$ clusters start to form  Finally for higher $T_{g}$, the magnetic contribution from Ge$_{3}$Mn$_{5}$ clusters keeps increasing while the nanocolumns signal progressively disappears 

\begin{figure}[htb]
\center
   \includegraphics[width= 6\linewidth]{ /fig7a eps}
   \includegraphics[width= 3\linewidth]{ /fig7b eps}
\caption{(a) Temperature dependence of the saturation magnetization (in $\mu_{B}$/Mn) of Ge$_{0 93}$Mn$_{0 07}$ samples for different growth temperatures  The magnetic field is applied in the film plane  The inset shows the temperature dependence of a sample grown at 130$^{\circ}$C and annealed at 650$^{\circ}$C for 15 minutes  After annealing, the magnetic signal mostly arises from Ge$_{3}$Mn$_{5}$ clusters  (b) ZFC-FC measurements performed on Ge$_{0 93}$Mn$_{0 07}$ samples for different growth temperatures  The in-plane applied field is 0 015 T  The ZFC peak at low temperature ($\leq$150 K) can be attributed to the superparamagnetic nanocolumns  This peak widens and shifts towards high blocking temperatures when increasing growth temperature  The second peak above 150 K in the ZFC curve which increases with increasing growth temperature is attributed to superparamagnetic Ge$_{3}$Mn$_{5}$ clusters  The increasing ZFC-FC irreversibility at $\approx$ 300 K is due to the increasing contribution from large ferromagnetic Ge$_{3}$Mn$_{5}$ clusters  The nanocolumns signal completely vanishes after annealing at 650$^{\circ}$C for 15 minutes }
\label{fig7}
\end{figure}

In Fig  7a, the saturation magnetization at 2 Tesla in $\mu_{B}$/Mn of Ge$_{1-x}$Mn$_{x}$ films with 7 \% of Mn is plotted as a function of temperature for different growth temperatures ranging from $T_{g}$=90$^{\circ}$C up to 160$^{\circ}$C  The inset shows the temperature dependence of the magnetization at 2 Tesla after annealing at 650$^{\circ}$C during 15 minutes  Figure 7b displays the corresponding Zero Field Cooled - Field Cooled (ZFC-FC) curves recorded at 0 015 Tesla  In the ZFC-FC procedure, the sample is first cooled down to 5 K in zero magnetic field and the susceptibility is subsequently recorded at 0 015 Tesla while increasing the temperature up to 400 K (ZFC curve)  Then, the susceptibility is recorded under the same magnetic field while decreasing the temperature down to 5 K (FC curve)  Three different regimes can be clearly distinguished  \\
For $T_{g}\leq$120$^{\circ}$C, the temperature dependence of the saturation magnetization remains nearly the same while increasing growth temperature  The overall magnetic signal vanishing above 200 K is attributed to the nanocolumns whereas the increasing signal below 50 K originates from diluted Mn atoms in the surrounding matrix  The Mn concentration dependence of the saturation magnetization is displayed in figure 8  For the lowest Mn concentration (4 \%), the contribution from diluted Mn atoms is very high and drops sharply for higher Mn concentrations (7 \%, 9 \% and 11 3 \%)  Therefore the fraction of Mn atoms in the diluted matrix decreases with Mn concentration probably because Mn atoms are more and more incorporated in the nanocolumns  In parallel, the Curie temperature of nanocolumns increases with the Mn concentration reaching 170 K for 11 3 \% of Mn  This behavior may be related to different Mn compositions and to the increasing diameter of nanocolumns (from 1 8 nm to 2 8 nm) as discussed in section \ref{structural} 

\begin{figure}[htb]
\center
   \includegraphics[width= 7\linewidth]{ /fig8 eps}
    \caption{Temperature dependence of the saturation magnetization (in $\mu_{B}$/Mn) of Ge$_{1-x}$Mn$_{x}$ films grown at 100$^{\circ}$C plotted for different Mn concentrations: 4 1 \%; 7 \%; 8 9 \% and 11 3 \% }
\label{fig8}
\end{figure}

ZFC-FC measurements show that the nanocolumns are superparamagnetic  The magnetic signal from the diluted Mn atoms in the matrix is too weak to be detected in susceptibility measurements at low temperature  In samples containing 4 \% of Mn, ZFC and FC curves superimpose down to low temperatures  As we do not observe hysteresis loops at low temperature, we believe that at this Mn concentration nanocolumns are  superparamagnetic in the whole temperature range and the blocking temperature cannot be measured  For higher Mn contents, the ZFC curve exhibits a very narrow peak with a maximum at the blocking temperature of 15 K whatever the Mn concentration and growth temperature (see Fig  7b)  Therefore the anisotropy barrier distribution is narrow and assuming that nanocolumns have the same magnetic anisotropy, this is a consequence of the very narrow size distribution of the nanocolumns as observed by TEM  To probe the anisotropy barrier distribution, we have performed ZFC-FC measurements but instead of warming the sample up to 400 K, we stopped at a lower temperature $T_{0}$  

\begin{figure}[htb]
\center
   \includegraphics[width= 6\linewidth]{ /fig9 eps}
\caption{Schematic drawing of the anisotropy barrier distribution n($E_{B}$) of superparamagnetic nanostructures  If magnetic anisotropy does not depend on the particle size, this distribution exactly reflects their magnetic size distribution  In this drawing the blocking temperature ($T_{B}$) corresponds to the distribution maximum  At a given temperature $T_{0}$ such that 25$k_{B}T_{0}$ falls into the anisotropy barrier distribution, the largest nanostructures with an anisotropy energy larger than 25$k_{B}T_{0}$ are blocked whereas the others are superparamagnetic }
\label{fig9}
\end{figure}

If this temperature falls into the anisotropy barrier distribution as depicted in Fig  9, the FC curve deviates from the ZFC curve  Indeed the smallest nanostructures have become superparamagnetic at $T_{0}$ and when decreasing again the temperature, their magnetization freezes along a direction close to the magnetic field and the FC susceptibility is higher than the ZFC susceptibility  Therefore any irreversibility in this procedure points at the presence of superparamagnetic nanostructures  The results are given in Fig  10a  ZFC and FC curves clearly superimpose up to $T_{0}$=250 K thus the nanocolumns are superparamagnetic up to their Curie temperature and no Ge$_{3}$Mn$_{5}$ clusters could be detected  Moreover for low $T_{0}$ values, a peak appears at low temperature in FC curves which evidences strong antiferromagnetic interactions between the nanocolumns \cite{Chan00} 

\begin{figure}[htb]
\center
    \includegraphics[width= 35\linewidth]{ /fig10a eps}
    \includegraphics[width= 63\linewidth]{ /fig10b eps}
\caption{(a) ZFC-FC measurements performed on a Ge$_{0 887}$Mn$_{0 113}$ sample grown at 115$^{\circ}$C  The in-plane applied field is 0 015 T  Magnetization was recorded up to different T$_{0}$ temperatures: 30 K, 50 K, 100 K, 150 K, 200 K and 250 K  Curves are shifted up for more clarity  (b) ZFC-FC curves for in-plane and out-of-plane applied fields (0 015 T) }
\label{fig10}
\end{figure}

In order to derive the magnetic size and anisotropy of the Mn-rich nanocolumns embedded in the Ge matrix, we have fitted the inverse normalized in-plane (resp  out-of-plane) susceptibility: $\chi_{\parallel}^{-1}$ (resp  $\chi_{\perp}^{-1}$)  The corresponding experimental ZFC-FC curves are reported in Fig  10b  Since susceptibility measurements are performed at low field (0 015 T), the matrix magnetic signal remains negligible  In order to normalize susceptibility data, we need to divide the magnetic moment by the saturated magnetic moment recorded at 5 T  However the matrix magnetic signal becomes very strong at 5 T and low temperature so that we need to subtract it from the saturated magnetic moment using a simple Curie function  From Fig  10b, we can conclude that nanocolumns are isotropic  Therefore to fit experimental data we use the following expression well suited for isotropic systems or cubic anisotropy: $\chi_{\parallel}^{-1}= \chi_{\perp}^{-1}\approx 3k_{B}T/M(T)+\mu_{0}H_{eff}(T)$  $k_{B}$ is the Boltzmann constant, $M=M_{s}v$ is the magnetic moment of a single-domain nanostructure (macrospin approximation) where $M_{s}$ is its magnetization and $v$ its volume  The in-plane magnetic field is applied along $[110]$ or $[-110]$ crystal axes  Since the nanostructures Curie temperature does not exceed 170 K, the temperature dependence of the saturation magnetization is also accounted for by writting $M(T)$  Antiferromagnetic interactions between nanostructures are also considered by adding an effective field estimated in the mean field approximation \cite{Fruc02}: $\mu_{0}H_{eff}(T)$ 
The only fitting parameters are the maximum magnetic moment (\textit{i e } at low temperature) per nanostructure: $M$ (in Bohr magnetons $\mu_{B}$) and the maximum interaction field (\textit{i e } at low temperature): $\mu_{0}H_{eff}$ 

\begin{figure}[htb]
\center
   \includegraphics[width= 7\linewidth]{ /fig11 eps}
\caption{Temperature dependence of the inverse in-plane (open circles) and out-of-plane (open squares) normalized susceptibilities of a Ge$_{0 887}$Mn$_{0 113}$ sample grown at 115$^{\circ}$C  Fits were performed assuming isotropic nanostructures or cubic anisotropy  Dashed line is for in-plane susceptibility and solid line for out-of-plane susceptibility }
\label{fig11}
\end{figure}

In Fig  11, the best fits lead to $M\approx$1250 $\mu_{B}$ and $\mu_{0}H_{eff}\approx$102 mT for in-plane susceptibility and $M\approx$1600 $\mu_{B}$ and $\mu_{0}H_{eff}\approx$98 mT for out-of-plane susceptibility  It gives an average magnetic moment of 1425 $\mu_{B}$ per column and an effective interaction field of 100 mT  Using this magnetic moment and its temperature dependence, magnetization curves could be fitted using a Langevin function and $M(H/T)$ curves superimpose for $T<$100 K  However, from the saturated magnetic moment of the columns and their density (35000 $\rm{\mu m}^{-2}$), we find almost 6000 $\mu_{B}$ per column  Therefore, for low growth temperatures, we need to assume that nanocolumns are actually made of almost four independent elongated magnetic nanostructures  The effective field for antiferromagnetic interactions between nanostructures estimated from the susceptibility fits is at least one order of magnitude larger than what is expected from pure magnetostatic coupling  This difference may be due to either an additional antiferromagnetic coupling through the matrix which origin remains unexplained or to the mean field approximation which is no more valid in this strong coupling regime  As for magnetic anisotropy, the nanostructures behave as isotropic magnetic systems or exhibit a cubic magnetic anisotropy  First we can confirm that nanostructures are not amorphous otherwise shape anisotropy would dominate leading to out-of-plane anisotropy  We can also rule out a random distribution of magnetic easy axes since the nanostructures are clearly crystallized in the diamond structure and would exhibit at least a cubic anisotropy (except if the random distribution of Mn atoms within the nanostructures can yield random easy axes)  Since the nanostructures are in strong in-plane compression (their lattice parameter is larger than the matrix one), the cubic symmetry of the diamond structure is broken and magnetic cubic anisotropy is thus unlikely  We rather believe that out-of-plane shape anisotropy is nearly compensated by in-plane magnetoelastic anisotropy due to compression leading to a \textit{pseudo} cubic anisotropy  From the blocking temperature (15 K) and the magnetic volume of the nanostructures , we can derive their magnetic anisotropy constant using $Kv=25k_{B}T_{B}$: K$\approx$10 kJ m$^{-3}$ which is of the same order of magnitude as shape anisotropy 

\begin{figure}[htb]
\center
    \includegraphics[width= 35\linewidth]{ /fig12a eps}
    \includegraphics[width= 63\linewidth]{ /fig12b eps} 
\caption{(a) ZFC-FC measurements performed on a Ge$_{0 93}$Mn$_{0 07}$ sample grown at 122$^{\circ}$C  The in-plane applied field is 0 015 T  Magnetization was recorded up to different T$_{0}$ temperatures: 50 K, 100 K, 150 K, 200 K and 250 K  Curves are shifted up for more clarity  (b) ZFC-FC curves for in-plane and out-of-plane applied fields  (0 015 T) }
\label{fig12}
\end{figure}

For growth temperatures $T_{g}\geq$120$^{\circ}$C and Mn concentrations $\geq$ 7 \%, samples exhibit a magnetic signal above 200 K corresponding to Ge$_{3}$Mn$_{5}$ clusters (see Fig  7a)  As we can see, SQUID measurements are much more sensitive to the presence of Ge$_{3}$Mn$_{5}$ clusters, even at low concentration, than TEM and x-ray diffraction used in section \ref{structural}  We also observe a sharp transition in the ZFC curve (see Fig  7b, Fig  12a and 12b): the peak becomes very large and is shifted towards high blocking temperatures (the signal is maximum at $T=$23 K)  This can be easily understood as a magnetic percolation of the four independent nanostructures obtained at low growth temperatures into a single magnetic nanocolumn  Therefore the magnetic volume increases sharply as well as blocking temperatures  At the same time, the size distribution widens as observed in TEM  In Fig  12a, we have performed ZFC-FC measurements at different $T_{0}$ temperatures  The ZFC-FC irreversibility is observed up to the Curie temperature of $\approx$120 K meaning that a fraction of nanocolumns is ferromagnetic (\textit{i e } $T_{B}\geq T_{C}$) 
In Fig  12b, in-plane and out-of-plane ZFC curves nearly superimpose for $T\leq$150 K due to the isotropic magnetic behavior of the nanocolumns: in-plane magnetoelastic anisotropy is still compensating out-of-plane shape anisotropy  Moreover the magnetic signal above 150 K corresponding to Ge$_{3}$Mn$_{5}$ clusters that start to form in this growth temperature range is strongly anisotropic  This perpendicular anisotropy confirms the epitaxial relation: (0002) Ge$_{3}$Mn$_{5}$ $\parallel$ (002) Ge discussed in Ref \cite{Bihl06}  The magnetic easy axis of the clusters lies along the hexagonal $c$-axis which is perpendicular to the film plane 

\begin{figure}[ht]
\center
   \includegraphics[width= 35\linewidth]{ /fig13a eps}
   \includegraphics[width= 63\linewidth]{ /fig13b eps} 
\caption{(a) ZFC-FC measurements performed on a Ge$_{0 887}$Mn$_{0 113}$ sample grown at 145$^{\circ}$C  The in-plane applied field is 0 015 T  Magnetization was recorded up to different T$_{0}$ temperatures: 50 K, 100 K, 150 K, 200 K, 250 K and 300 K  Curves are shifted up for more clarity  (b) ZFC-FC curves for in-plane and out-of-plane applied fields (0 015 T) }
\label{fig13}
\end{figure}

For growth temperatures $T_{g}\geq$145$^{\circ}$C the cluster magnetic signal dominates (Fig  13b)  Superparamagnetic nanostructures are investigated performing ZFC-FC measurements at different $T_{0}$ temperatures (Fig  13a)  The first ZFC peak at low temperature \textit{i e } $\leq$ 150 K is attributed to  low-$T_{C}$ nanocolumns ($T_{C}\approx$130 K)  This peak is wider than for lower growth temperatures and its maximum is further shifted up to 30 K  These results are in agreement with TEM observations: increasing $T_{g}$ leads to larger nanocolumns (\textit{i e } higher blocking temperatures) and wider size distributions  ZFC-FC irreversibility is observed up to the Curie temperature due to the presence of ferromagnetic columns  The second peak above 180 K in the ZFC curve is attributed to Ge$_{3}$Mn$_{5}$ clusters and the corresponding ZFC-FC irreversibility persisting up to 300 K means that some clusters are ferromagnetic  We clearly evidence the out-of-plane anisotropy of Ge$_{3}$Mn$_{5}$ clusters and the isotropic magnetic behavior of nanocolumns (Fig  13b)  In this growth temperature range, we have also investigated the Mn concentration dependence of magnetic properties  

\begin{figure}[ht]
\center
    \includegraphics[width= 49\linewidth]{ /fig14a eps}
    \includegraphics[width= 49\linewidth]{ /fig14b eps} 
\caption{Temperature dependence of the saturation magnetization (in $\mu_{B}$/Mn) of Ge$_{1-x}$Mn$_{x}$ films grown at 150$^{\circ}$C plotted for different Mn concentrations: 2 3 \%; 4 \%; 7 \%; 9 \%; 11 3 \%  (b) ZFC-FC measurements performed on Ge$_{1-x}$Mn$_{x}$ films grown at 150$^{\circ}$C  The in-plane applied field is 0 025 T for 2 3 \% and 4 \% and 0 015 T for 8 \% and 11 3 \%  }
\label{fig14}
\end{figure}

In Fig  14a, for low Mn concentrations (2 3 \% and 4 \%) the contribution from diluted Mn atoms in the germanium matrix to the saturation magnetization is very high and nearly vanishes for higher Mn concentrations (7 \%, 9 \% and 13 \%) as observed for low growth temperatures  Above 7 \%, the magnetic signal mainly comes from nanocolumns and Ge$_{3}$Mn$_{5}$ clusters  We can derive more information from ZFC-FC measurements (Fig  14b)  Indeed, for 2 3 \% of Mn, ZFC and FC curves nearly superimpose down to low temperature meaning that nanocolumns are superparamagnetic in the whole temperature range  Moreover the weak irreversibility arising at 300 K  means that some Ge$_{3}$Mn$_{5}$ clusters have already formed in the samples even at very low Mn concentrations  For 4 \% of Mn, we can observe a peak with a maximum at the blocking temperature (12 K) in the ZFC curve  We can also derive the Curie temperature of nanocolumns: $\approx$45 K  The irresversibility arising at 300 K still comes from Ge$_{3}$Mn$_{5}$ clusters  Increasing the Mn concentration above 7 \% leads to: higher blocking temperatures (20 K and 30 K) due to larger nanocolumns and wider ZFC peaks due to wider size distributions in agreement with TEM observations (see Fig  3a)  Curie temperatures also increase (110 K and 130 K) as well as the contribution from Ge$_{3}$Mn$_{5}$ clusters \\
Finally when increasing $T_{g}$ above 160$^{\circ}$C, the nanocolumns magnetic signal vanishes and only Ge$_{3}$Mn$_{5}$ clusters and diluted Mn atoms coexist  The overall magnetic signal becomes comparable to the one measured on annealed samples in which only Ge$_{3}$Mn$_{5}$ clusters are observed by TEM (see Fig  7a) \\
The magnetic properties of high-$T_{C}$ nanocolumns obtained for $T_{g}$ close to 130$^{\circ}$C are discussed in detail in Ref \cite{Jame06} \\
In conclusion, at low growth temperatures ($T_{g}\leq$120$^{\circ}$C), nanocolumns are made of almost 4 independent elongated magnetic nanostructures  For $T_{g}\geq$120$^{\circ}$C, these independent nanostructures percolate into a single nanocolumn sharply leading to higher blocking temperatures  Increasing $T_{g}$ leads to larger columns with a wider size distribution as evidenced by ZFC-FC measurements and given by TEM observations  In parallel, some Ge$_{3}$Mn$_{5}$ clusters start to form and their contribution increases when increasing $T_{g}$  Results on magnetic anisotropy seems counter-intuitive  Indeed Ge$_{3}$Mn$_{5}$ clusters exhibit strong out-of-plane anisotropy whereas nanocolumns which are highly elongated magnetic structures are almost isotropic  This effect is probably due to compensating in-plane magnetoelastic coupling (due to the columns compression) and out-of-plane shape anisotropy  

\section{Conclusion}

In this paper, we have investigated the structural and magnetic properties of thin Ge$_{1-x}$Mn$_{x}$ films grown by low temperature molecular beam epitaxy  A wide range of growth temperatures and Mn concentrations have been explored  All the samples contain Mn-rich nanocolumns as a consequence of 2D-spinodal decomposition  However their size, crystalline structure and magnetic properties depend on growth temperature and Mn concentration  For low growth temperatures, nanocolumns are very small (their diameter ranges between 1 8 nm for 1 3 \% of Mn and 2 8 nm for 11 3 \% of Mn), their Curie temperature is rather low ($<$ 170 K) and they behave as almost four uncorrelated superparamagnetic nanostructures  Increasing Mn concentration leads to higher columns densities while diameters remain nearly unchanged  For higher growth temperatures, the nanocolumns mean diameter increases and their size distribution widens  Moreover the 4 independent magnetic nanostructures percolate into a single magnetic nanocolumn  Some columns are ferromagnetic even if Curie temperatures remain quite low  In this regime, increasing Mn concentration leads to larger columns while their density remains nearly the same  In parallel, Ge$_{3}$Mn$_{5}$ nanoclusters start to form in the film with their $c$-axis perpendicular to the film plane  In both temperature regimes, the Mn incorporation mechanism in the nanocolumns and/or in the matrix changes above 5 \% of Mn and nanocolumns exhibit an isotropic magnetic behaviour due to the competing effects of out-of-plane shape anisotropy and in-plane magnetoelastic coupling  Finally for a narrow range of growth temperatures around 130$^{\circ}$C, nanocolumns exhibit Curie temperatures higher than 400 K  Our goal is now to investigate the crystalline structure inside the nanocolumns, in particular the position of Mn atoms in the distorted diamond structure, which is essential to understand magnetic and future transport properties in Ge$_{1-x}$Mn$_{x}$ films 

\section{Aknowledgements}
The authors would like to thank Dr  F  Rieutord for grazing incidence x-ray diffraction measurements performed on the GMT station of BM32 beamline at the European Synchrotron Radiation Facility 


Context 3: Publications of Kam W  Leong
Publications of Kam W  Leong :chronological alphabetical combined bibtex listing:
K W  Leong, Synthetic mast-cell granules as adjuvants to promote and polarize immunity in lymph nodes (2013) [PDF]
K W  Leong, Tuning Physical Properties of Nanocomplexes through Microfluidics-Assisted Confinement (2013) [PDF]
K W  Leong, Nucleic acid scavengers inhibit thrombosis without increasing bleeding (2013) [PDF]
K W  Leong, Nanotopography as modulator of human mesenchymal stem cell function (2013) [PDF]
K W  Leong, Efficacy of engineered FVIII-producing skeletal muscle enhanced by growth factor-releasing co-axial electrospun fibers (2013) [PDF]
Zhao, F  and Veldhuis, J  J  and Duan, Y  J  and Yang, Y  and Christoforou, N  and Ma, T  and Leong, K  W , Low Oxygen Tension and Synthetic Nanogratings Improve the Uniformity and Stemness of Human Mesenchymal Stem Cell Layer, Molecular Therapy, vol  18 no  5 (2010), pp  1010-1018 [abs]
Kadiyala, I  and Loo, Y  H  and Roy, K  and Rice, J  and Leong, K  W , Transport of chitosan-DNA nanoparticles in human intestinal M-cell model versus normal intestinal enterocytes, European Journal of Pharmaceutical Sciences, vol  39 no  1-3 (2010), pp  103-109 [abs]
Wang, Y  and Quek, C  H  and Leong, K W  and Fang, J , Synthesis and Cytotoxity of Luminescent InP Quantum Dots, MRS Symposium Proceeding, vol  1241E (2010)
Jiang, X  and Zheng, Y  and Chen, H  H  and Leong, K  W  and Wang, T  H  and Mao, H  Q , Dual-Sensitive Micellar Nanoparticles Regulate DNA Unpacking and Enhance Gene-Delivery Efficiency, Adv Mater (2010)
Ho, Y  P  and Leong, K  W , Quantum dot-based theranostics, Nanoscale, vol  2 no  1 (2010), pp  60-68 [PDF] [abs]
Phua, K  and Leong, K  W , Microscale oral delivery devices incorporating nanoparticles, Nanomedicine, vol  5 no  2 (2010), pp  161-163
Grigsby, C  L  and Leong, K  W , Balancing protection and release of DNA: tools to address a bottleneck of non-viral gene delivery, Journal of the Royal Society Interface, vol  7 (2010), pp  S67-S82 [abs]
Chalut, K  J  and Kulangara, K  and Giacomelli, M  G  and Wax, A  and Leong, K  W , Deformation of stem cell nuclei by nanotopographical cues, Soft Matter, vol  6 no  8 (2010), pp  1675-1681 [abs]
Chen, S  and Jones, J  A  and Xu, Y  and Low, H  Y  and Anderson, J  M  and Leong, K  W , Characterization of topographical effects on macrophage behavior in a foreign body response model, Biomaterials, vol  31 no  13 (2010), pp  3479-91 [PDF] [abs]
Yim, E  K  F  and Darling, E  M  and Kulangara, K  and Guilak, F  and Leong, K  W , Nanotopography-induced changes in focal adhesions, cytoskeletal organization, and mechanical properties of human mesenchymal stem cells, Biomaterials, vol  31 no  6 (2010), pp  1299-1306 [PDF] [abs]
Yow, S  Z  and Quek, C  H  and Yim, E  K  F  and Lim, C  T  and Leong, K  W , Collagen-based fibrous scaffold for spatial organization of encapsulated and seeded human mesenchymal stem cells, Biomaterials, vol  30 no  6 (2009), pp  1133-1142 [abs]
Kunder, C  A  and John, A  L  S  and Li, G  J  and Leong, K  W  and Berwin, B  and Staats, H  F  and Abraham, S  N , Mast cell-derived particles deliver peripheral signals to remote lymph nodes, Journal of Experimental Medicine, vol  206 no  11 (2009), pp  2455-2467 [abs]
Ho, Y P  and Chen, H H  and Leong, K W  and Wang, T H , Combining QD-FRET and microfluidics to monitor DNA nanocomplex self-assembly in real-time, J Vis Exp (2009), pp  1432
Kulangara, K  and Leong, K  W , Substrate topography shapes cell function, Soft Matter, vol  5 no  21 (2009), pp  4072-4076 [abs]
Chakraborty, S  and Liao, I  C  and Adler, A  and Leong, K  W , Electrohydrodynamics: A facile technique to fabricate drug delivery systems, Advanced Drug Delivery Reviews, vol  61 no  12 (2009), pp  1043-1054 [abs]
Oney, S  and Lam, R  T  S  and Bompiani, K  M  and Blake, C  M  and Quick, G  and Heidel, J  D  and Liu, J  Y  C  and Mack, B  C  and Davis, M  E  and Leong, K  W  and Sullenger, B  A , Development of universal antidotes to control aptamer activity, Nature Medicine, vol  15 no  10 (2009), pp  1224-1228 [PDF] [abs]
Chen, H  H  and Ho, Y  P  and Jiang, X  and Mao, H  Q  and Wang, T  H  and Leong, K  W , Simultaneous non-invasive analysis of DNA condensation and stability by two-step QD-FRET, Nano Today, vol  4 no  2 (2009), pp  125-134 [PDF] [abs]
Ho, Y  P  and Chen, H  H  and Leong, K  W  and Wang, T  H , The convergence of quantum-dot-mediated fluorescence resonance energy transfer and microfluidics for monitoring DNA polyplex self-assembly in real time, Nanotechnology, vol  20 no



ground_truth: It becomes a bit less so that what's off to the left or right can be better noted.

prompt_front: Now, answer the following question based on the text below, only give me the answer and do not output any other words.

Question: What is the average magnetic moment per column in Ge$_{1-x}$Mn$_{x}$ films?

Read the following text and answer briefly.

Context 3:  9 (2009), pp  - [abs]
Liao, I  C  and Chen, S  L  and Liu, J  B  and Leong, K  W , Sustained viral gene delivery through core-shell fibers, Journal of Controlled Release, vol  139 no  1 (2009), pp  48-55 [abs]
Lou, Y  L  and Peng, Y  S  and Chen, B  H  and Wang, L  F  and Leong, K  W , Poly(ethylene imine)-g-chitosan using EX-810 as a spacer for nonviral gene delivery vectors, Journal of Biomedical Materials Research Part A, vol  88A no  4 (2009), pp  1058-1068 [abs]
Chew, S  Y  and Mi, R  and Hoke, A  and Leong, K  W , The effect of the alignment of electrospun fibrous scaffolds on Schwann cell maturation, Biomaterials, vol  29 no  6 (2008), pp  653-61 [abs]
Chen, H  H  and Ho, Y  P  and Jiang, X  and Mao, H  Q  and Wang, T  H  and Leong, K  W , Quantitative comparison of intracellular unpacking kinetics of polyplexes by a model constructed from quantum Dot-FRET, Molecular Therapy, vol  16 no  2 (2008), pp  324-332 [abs]
Chan, B  P  and Leong, K  W , Scaffolding in tissue engineering: general approaches and tissue-specific considerations, European Spine Journal, vol  17 (2008), pp  S467-S479 [abs]
Tsurushima, H  and Yuan, X  and Dillehay, L  E  and Leong, K  W , Radiation-inducible caspase-8 gene therapy for malignant brain tumors, International Journal of Radiation Oncology Biology Physics, vol  71 no  2 (2008), pp  517-525 [abs]
Bowman, K  and Sarkar, R  and Raut, S  and Leong, K  W , Gene transfer to hemophilia A mice via oral delivery of FVIII-chitosan nanoparticles, Journal of Controlled Release, vol  132 no  3 (2008), pp  252-259 [abs]
Choi, J  S  and Leong, K  W  and Yoo, H  S , In vivo wound healing of diabetic ulcers using electrospun nanofibers immobilized with human epidermal growth factor (EGF), Biomaterials, vol  29 no  5 (2008), pp  587-96 [abs]
Liao, I  C  and Liu, J  B  and Bursac, N  and Leong, K  W , Effect of Electromechanical Stimulation on the Maturation of Myotubes on Aligned Electrospun Fibers, Cellular and Molecular Bioengineering, vol  1 no  2-3 (2008), pp  133-145 [abs]
Prow, T  W  and Bhutto, I  and Kim, S  Y  and Grebe, R  and Merges, C  and McLeod, D  S  and Uno, K  and Mennon, M  and Rodriguez, L  and Leong, K  and Lutty, G  A , Ocular nanoparticle toxicity and transfection of the retina and retinal pigment epithelium, Nanomedicine-Nanotechnology Biology and Medicine, vol  4 no  4 (2008), pp  340-349 [abs]
Tan, S  C  W  and Pan, W  X  and Ma, G  and Cai, N  and Leong, K  W  and Liao, K , Viscoelastic behaviour of human mesenchymal stem cells, Bmc Cell Biology, vol  9 (2008), pp  - [abs]
Chalut, K  J  and Chen, S  and Finan, J  D  and Giacomelli, M  G  and Guilak, F  and Leong, K  W  and Wax, A , Label-free, high-throughput measurements of dynamic changes in cell nuclei using angle-resolved low coherence interferometry, Biophysical Journal, vol  94 no  12 (2008), pp  4948-4956 [abs]
Haider, M  and Cappello, J  and Ghandehari, H  and Leong, K  W , In vitro chondrogenesis of mesenchymal stem cells in recombinant silk-elastinlike hydrogels, Pharmaceutical Research, vol  25 no  3 (2008), pp  692-699 [abs]
N  Bursac and Y  H  Loo and K  Leong and L  Tung, Novel anisotropic engineered cardiac tissues: Studies of electrical propagation, Biochemical And Biophysical Research Communications, vol  361 no  4 (October, 2007), pp  847 -- 853, ISSN 0006-291X [abs]
Chen, Beiyi and Dang, Jiyoung and Tan, Tuan Lin and Fang, Ning and Chen, Wei Ning and Leong, Kam W  and Chan, Vincent, Dynamics of smooth muscle cell deadhesion from thermosensitive hydroxybutyl chitosan, Biomaterials, vol  28 no  8 (2007), pp  1503 - 1514 [027] [abs]
Chen, B  and Dang, J  and Tan, T  L  and Fang, N  and Chen, W  N  and Leong, K  W  and Chan, V , Dynamics of smooth muscle cell deadhesion from thermosensitive hydroxybutyl chitosan, Biomaterials, vol  28 no  8 (2007), pp  1503-14 [abs]
Park, D  J  and Choi, J  H  and Leong, K  W  and Kwon, J  W  and Eun, H  S , Tissue-engineered bone formation with gene transfer and mesenchymal stem cells in a minimally invasive technique, Laryngoscope, vol  117 no  7 (2007), pp  1267-71 [abs]
Tsurushima, H  and Yuan, X  and Dillehay, L  E  and Leong, K  W , Radioresponsive tumor necrosis factor-related apoptosisinducing ligand (TRAIL) gene therapy for malignant brain tumors, Cancer Gene Therapy, vol  14 no  8 (2007), pp  706-716 [abs]
Chai, C  and Leong, K  W , Biomaterials approach to expand and direct differentiation of stem cells, Molecular Therapy, vol  15 no  3 (2007), pp  467-480 [abs]
Zhang, Y  and Chai, C  and Jiang, X  S  and Teoh, S  H  and Leong, K  W , Fibronectin immobilized by covalent conjugation or physical adsorption shows different bioactivity on aminated-PET, Materials Science & Engineering C-Biomimetic and Supramolecular Systems, vol  27 no  2 (2007), pp  213-219 [abs]
Song, R  J  and Liu, S  Q  and Leong, K



ground_truth: 1425 $\mu_{B}$.

prompt_front: Now, answer the following question based on the text below, only give me the answer and do not output any other words.

Question: What are the titles of one of Kam W. Leong's publications in Journal of Controlled Release?

Read the following text and answer briefly.

Context 3:  W , Effects of MIP-1 alpha, MIP-3 alpha, and MIP-3 beta on the induction of HIV Gag-specific immune response with DNA vaccines, Molecular Therapy, vol  15 no  5 (2007), pp  1007-1015 [abs]
Yim, E  K  F  and Liao, I  C  and Leong, K  W , Tissue compatibility of interfacial polyelectrolyte complexation fibrous scaffold: Evaluation of blood compatibility and biocompatibility, Tissue Engineering, vol  13 no  2 (2007), pp  423-433 [abs]
Sharma, B  and Williams, C  G  and Kim, T  K  and Sun, D  N  and Malik, A  and Khan, M  and Leong, K  and Elisseeff, J  H , Designing zonal organization into tissue-engineered cartilage, Tissue Engineering, vol  13 no  2 (2007), pp  405-414 [abs]
Chua, K  N  and Tang, Y  N  and Quek, C  H  and Ramakrishna, S  and Leong, K  W  and Mao, H  Q , A dual-functional fibrous scaffold enhances P450 activity of cultured primary rat hepatocytes, Acta Biomaterialia, vol  3 no  5 (2007), pp  643-650 [abs]
Chua, K  N  and Chai, C  and Lee, P  C  and Ramakrishna, S  and Leong, K  W  and Mao, H  Q , Functional nanofiber scaffolds with different spacers modulate adhesion and expansion of cryopreserved umbilical cord blood hematopoietic stem/progenitor cells, Experimental Hematology, vol  35 no  5 (2007), pp  771-781 [abs]
Yim, E  K  F  and Pang, S  W  and Leong, K  W , Synthetic nanostructures inducing differentiation of human mesenchymal stem cells into neuronal lineage, Experimental Cell Research, vol  313 no  9 (2007), pp  1820-1829 [abs]
Chew, S  Y  and Mi, R  F  and Hoke, A  and Leong, K  W , Aligned protein-polymer composite fibers enhance nerve regeneration: A potential tissue-engineering platform, Advanced Functional Materials, vol  17 no  8 (2007), pp  1288-1296 [abs]
Tsurushima, H  and Yuan, X  and Dillehay, L  E  and Leong, K  W , Radio-responsive gene therapy for malignant glioma cells without the radiosensitive promoter: Caspase-3 gene therapy combined with radiation, Cancer Letters, vol  246 no  1-2 (2007), pp  318-323 [abs]
Dang, J M  and Leong, K  W , Myogenic induction of aligned mesenchymal stem cell sheets by culture on thermally responsive electrospun nanofibers, Advanced Materials, vol  19 no  19 (2007), pp  2775-2779
Dai, H  and Jiang, X  and Tan, G  C  and Chen, Y  and Torbenson, M  and Leong, K  W  and Mao, H  Q , Chitosan-DNA nanoparticles delivered by intrabiliary infusion enhance liver-targeted gene delivery, International Journal of Nanomedicine, vol  1 no  4 (2006), pp  507-522 [abs]
Le Visage, C  and Kim, S  W  and Tateno, K  and Sieber, A  N  and Kostuik, J  P  and Leong, K  W , Interaction of human mesenchymal stem cells with disc cells - Changes in extracellular matrix biosynthesis, Spine, vol  31 no  18 (2006), pp  2036-2042
Ong, S  Y  and Dai, H  and Leong, K  W , Inducing hepatic differentiation of human mesenchymal stem cells in pellet culture, Biomaterials, vol  27 no  22 (2006), pp  4087-4097
Bright, C  and Park, Y  S  and Sieber, A  N  and Kostuik, J  P  and Leong, K  W , In vivo evaluation of plasmid DNA encoding OP-1 protein for spine fusion, Spine, vol  31 no  19 (2006), pp  2163-2172
Yim, E  K  and Wan, A  C  and Le Visage, C  and Liao, I  C  and Leong, K  W , Proliferation and differentiation of human mesenchymal stem cell encapsulated in polyelectrolyte complexation fibrous scaffold, Biomaterials, vol  27 no  36 (2006), pp  6111-22 [abs]
Luong-Van, E  and Grondahl, L  and Chua, K  N  and Leong, K  W  and Nurcombe, V  and Cool, S  M , Controlled release of heparin from poly(epsilon-caprolactone) electrospun fibers, Biomaterials, vol  27 no  9 (2006), pp  2042-2050
Dang, J  M  and Leong, K  W , Natural polymers for gene delivery and tissue engineering, Advanced Drug Delivery Reviews, vol  58 no  4 (2006), pp  487-499
Li, J  and Li, X  and Ni, X  P  and Wang, X  and Li, H  Z  and Leong, K  W , Self-assembled supramolecular hydrogels formed by biodegradable PEO-PHB-PEO triblock copolymers and alpha-cyclodextrin for controlled drug delivery, Biomaterials, vol  27 no  22 (2006), pp  4132-4140
Yim, E  K  F  and Wen, J  and Leong, K  W , Enhanced extracellular matrix production and differentiation of human embryonic germ cell derivatives in biodegradable poly(epsilon-caprolactone-co-ethyl ethylene phosphate) scaffold, Acta Biomaterialia, vol  2 no  4 (2006), pp  365-376
Chew, S  Y  and Hufnagel, T  C  and Lim, C  T  and Leong, K  W , Mechanical properties of single electrospun drug-encapsulated nanofibres, Nanotechnology, vol  17 no  15 (2006), pp  3880-3891
Zhang, Y  and Chai, C  and Jiang, X  S  and Teoh, S  H  and Leong, K  W , Co-culture of umbilical cord blood CD34(+) cells with human mesenchymal stem cells, Tissue Engineering, vol  12 no  8



ground_truth: Sustained viral gene delivery through core-shell fibers and Gene transfer to hemophilia A mice via oral delivery of FVIII-chitosan nanoparticles.