bluuebunny/crossref_metadata_2025 huggingface dataset:
DNA higher-order structures
Authors: Olson Wilma K
Published: November 2023

The packaging of DNA within the close confines of the cell imposes a higher order structure on the long, thread-like molecule. The chain must fold within a highly crowded environment as well as adopt arrangements that allow for correct recognition and processing of the genetic message. This organizational structure, which is too unwieldy for direct molecular characterization, can only be inferred from the physical properties of relevant model systems. Isolated DNA supercoils with intertwined double helical strands constitute one such useful model. The well-known interplay between long-range structure and local twisting of the supercoil can be used to drive the folding of DNA around proteins and other packaging agents. The long-range association between interwound strands is relevant to the close packing of DNA, while the local structural changes provide insight into the transient opening of the double helix during biological processes.
Transfer RNA
Authors: G John , Moras Dino
Published: November 2023

Transfer RNA (tRNA) is the key intermediate in the process of protein synthesis. It is a link between genetic information contained in nucleic acids and its expression in the protein world. The molecule possesses two important ends; one interacts with the codon of the messenger RNA (mRNA) through three specific nucleotides called the anticodon, while the other end serves as the attachment point for the amino acid and is subseqently linked to a growing polypeptide chain during protein synthesis on the ribosome. Thus, the molecule adapts the amino acids to the genetic code.
On Four-Dimensional Einstein Manifolds
Authors: LeBrun Claude
Published: November 2023

In dimensions ≥4, equation (1.1) no longer determines the geometry in a local manner, and this vastly increases both the interest and the difficulty of understanding Einstein manifolds in higher dimensions. In dimensions ≥5, our knowledge of general Einstein manifolds is quite scant, although an impressive array of methods has been developed for producing and classifying Einstein manifolds with special holonomy or isometry groups, Aubin (1976), Besse (1987), Boyer et al. (1994), Joyce (1996), Yau (1977).
Loss of Information in Black Holes
Authors: Hawking Stephen
Published: November 2023

It is a pleasure to be here to celebrate Roger’s birthday. Like many people, I find it difficult to believe he is about to be 65. I just hope I am in such good form when I reach that age. When I began research in the early 1960s, general relativity was at a low ebb. Many of you will have read Feynman’s comments, on a conference on general relativity that he attended. I believe it was at Chapel Hill. At that time, there was no contact with observations. Most people in the field spent their time doing messy calculations of Christoffel symbols. They were so pleased if they found a solution that they did not care what physical significance it had, if any.
The Penrose Transform and Real Integral Geometry
Authors: Bailey Toby N
Published: November 2023

I remember, some years ago, Roger Penrose drawing a picture of twistor theory as a tree, which he was trying to train mainly towards fundamental physics, but which was always sending off vigorous shoots in the direction of pure mathematics. Twistor theory has certainly been a source of an astonishing amount of mathematics. One example is what we now call the Penrose transform, and in this note I want to report on some joint research with Michael Eastwood (Bailey and Eastwood 1997), whereby methods involving holomorphic geometry inspired by the Penrose transform are used to obtain results on transforms in real integral geometry. (This follows on from joint work with Eastwood, Rod Gover and Lionel Mason (1997). It was Mason’s idea originally that one ought to be able to obtain results of this sort.) A full account of our results appears in (Bailey and Eastwood 1997), and here I want just to outline the methods and make more precise the connection with the Penrose transform which is largely suppressed in (Bailey and Eastwood 1997).
Pythagorean Spinors and Penrose Twistors
Authors: Trautman Andrzej
Published: November 2023

Originally, Roger Penrose intended twistor spaces to be associated with, or serve as replacements for, the 4-dimensional, Lorentzian space-times. His belief in the privileged and exceptional role of four dimensions, apparent in twistor theory, was strikingly confirmed by the discoveries of exotic differential structures on JR4, and of the Donaldson and Seiberg-Witten invariants. There are, however, interesting generalizations of twistor ideas to other dimensions and signatures; especially to proper Riemannian 3- and 4-manifolds. As is often the case with important ideas, the original notion of twistor has been generalized in many ways; only some of them are briefly presented below.
Systems
Authors: Freer Stephen
Published: November 2023

To the Orthodox (26) SYSTEMATISTS (24) we owe the clarity and accuracy of botanical science CESALPINO (28) is a fructist and the first true systematist; he divides according to the positions of the corcle (86: VI) and the receptacle (86: VII).
Differentiation of integrals
Authors: Priestley H A
Published: November 2023

In the previous chapter we presented the Continuous DCT and gave some simple applications. Here we focus on its use in establishing differentiability of functions defined by integrals, as foreshadowed in Chapter 19. The rudiments of the method are covered in 20.2-20.6; other sections may be studied only as needed.
Measurable sets
Authors: Priestley H A
Published: November 2023

This chapter investigates the notion of the length, or measure, of a subset S of ℝ. Many texts on integration take the notion of measure as fundamental, and develop the theory of integrals from a theory of measure. We do quite the opposite, using what we have already learnt about intervals and integrals to give a meaningful concept of length for as wide a class of sets as possible.
Integrable functions on ℝk
Authors: Priestley H A
Published: November 2023

Areas are to integrals of functions of one variable as volumes are to integrals of functions of two variables. A first course in multi-variable calculus oriented towards applied mathematics customarily treats ‘double’ and ‘triple’ integrals at the same level of mathematical sophistication as does a first course in I-variable calculus. In developing the I-variable Lebesgue theory, we provided LC as a stepping stone to L, which we shall here call L(ℝ). A similar stepping stone is of little assistance in higher dimensions. However we have set up our theory of L(ℝ) in such a way that it extends to higher dimensions with only notational changes.
Basic applications of parallel matching
Authors: Karpinski Marek , Rytter Wojciech
Published: November 2023

In this chapter we present some natural applications of parallel algorithms for maximum matchings. We show that due to RNC-algorithms for maximum matchings there exist RNC-algorithms for the following problems: maximum disjoint paths, optimal flows in some networks, DFS-tree construction and subtree isomorphism. If there is an NC-algorithm for maximum matchings then there are NC-algorithms for each of the above problems. Hence the maximum matching problem is the main representative of an important class of combinatorial problems NC-reducible to it. Two unrooted undirected trees T’, T” are isomorphic (we write T’ = T”) iff they have the same shape, that is iff they are isomorphic in the sense of undirected unlabeled graphs. There are linear time sequential algorithms and optimal NC¬ algorithms to test tree isomorphism. However, the problem of subtree isomorphism is much more complex. The subtree isomorphism problem can be defined as follows: there are two trees Tl, T2, test if there is a subtree T of T2 such that Tl= T2. The main result of this section is an RNC-algorithm for the subtree isomorphism problem. We also show that this problem is in NC if and only if the perfect matching problem for bipartite graphs is in NC. It is usually much easier to deal with rooted directed trees: two such trees T’, T” are isomorphic iff there is a bijection between their sets of nodes such that the roots correspond to each other, and the bijection preserves the relation “to be a father of” .
More applications
Authors: Karpinski Marek , Rytter Wojciech
Published: November 2023

We now sketch more applications of parallel algorithms for matching problems. We show that owing to the existence of RNC-algorithms for maximum matchings there exist RNC-algorithms for the following problems: bandwidth approximation, superstring approximation, cycle cover, approximate Metric TSP, unary Chinese postman problem, two-processor scheduling and the approximate Steiner tree problem. Consider the following problem. A postman is supposed to deliver the mail with in his part of the city. He starts at a post office and has to walk along each street at least once. Finally he has to return to the post office. We model the street graph as an undirected graph. For simplicity assume that each street has the same length (the unary version). Assume the graph is connected. We want to find the postman’s route which minimizes the length of the route. Observe that some streets have to be traversed more than once, unless the graph is Eulerian. We call this problem the unary postman problem.
Convergence and divergence
Authors: Boos Johann , Cass Peter
Published: November 2023

This first chapter has an introductory character. We start in Section 1.1 with some remarks about the early history of summability, that is about the history from the time when the essential evolution of summability started until the end of the nineteenth century.
Basic Definitions
Authors: David Guy , Semmes Stephen
Published: November 2023

In this chapter we define the notions of BPI spaces and BPI equivalence, which are central to our study of self-similar geometry.
Regular Mappings
Authors: David Guy , Semmes Stephen
Published: November 2023

In order to relate the geometry of spaces we want to look at mappings more general than bilipschitz. We can look at Lipschitz mappings, but they can be very degenerate. Regular mappings, defined below, provide a class of nondegenerate Lipschitz mappings for which we have some tools to establish their existence.
Heterogeneous Domain Decomposition Methods
Authors: Quarteroni Alfio , Valli Alberto
Published: November 2023

In this chapter we address the case of heterogeneous domain decomposition, arising whenever, in the approximation of certain physical phenomena, two different kinds of (initial-) boundary value problems hold within two disjoined subregions of the computational domain.
Airflow Over Wavy Surfaces: Anomalies, A Conjecture and Some Results
Authors: Weng Wensong , Xu Dapeng
Published: November 2023

Although there have been significant advances in our understanding of the mechanism by which water waves are generated by wind there remain quantitative differences between model predictions and observations of the rate at which energy is transferred from the wind to waves. Wind tunnel studies and theoretical investigations of the airflow over fixed waves have revealed that turbulent boundary-layer flow over two dimensional waves can develop stable secondary flows in the form of pairs of counterrotating longitudinal vortices. It is conjectured, though not demonstrated, that the same mechanism may be active in airflow over water waves and could enhance the rate of energy transfer to the waves. Some numerical model results of the development of vortex pairs in the flow over fixed waves are presented.
Drift Current under the Action of Wind and Waves
Authors: Spaulding Malcolm
Published: November 2023

Accurate estimates of sea surface drift currents are critical to forecast ing oil spill transport and fate and the movement of objects lost at sea. The majority of existing models employ a drift factor and deflection angle, based on the local wind speed and direction, to estimate the wind induced sea surface drift vector. The effects of wind induced shear and wave induced transport are lumped together in this formulation. In the present study the conservation of momentum and turbulent kinetic energy equations are solved using an implicit finite difference scheme to predict the vertical distribution of currents, turbulent kinetic energy, and vertical eddy viscosity at one point. The model includes coupling between the wave and shear induced currents. Inputs of momentum and energy from the atmosphere to the current and turbulent energy fields are parameterized through free surface boundary conditions. The numerical model has been extensively tested against analytic solutions for wind forced shear flow and prior work on wave current interaction with very good results. The model was applied to predict the steady state surface drift currents for varying wind speeds in deep water.
Turbulence Structure and Mass Transfer at a Wind-Driven Air-Water Interface
Authors: Komori Satoru , Shimada Takashi , Misumi Ryuta
Published: November 2023

The CO2 transfer velocity across the air-sea interface was estimated through laboratory experiments in both a wind-wave tank and an oscillating grid tank. The results show that the CO2 transfer velocity is not affected by contaminants characteristic of natural sea water, but the CO2 transfer velocity of sea water is damped to 50% of the transfer velocity of fresh water for non-breaking air-water interfaces. The damping is caused by the reduction of apparent molecular diffusivity at the interface due to tiny surface-active impurities.
Turbulence Modelling Near Interfaces: The Case for TCL Closures
Authors: Launder Brian E
Published: November 2023

The problem of predicting turbulent stresses and fluxes in the vicinity of an abrupt interface is considered, a class of flow phenomena that arises widely in stratified flows both in engineering and the environment. Second moment closures have in the past been applied to fairly simple problems of this type with “wall-reflection” terms being used to mimic the non viscous damping of turbulent transport that arises at the interface. It is argued, however, that a more generally valid approach needs to build on a modelling strategy that fully respects the two-component limit (TCL) to which turbulence must reduce at these interfaces. A summary of the closure developed by Craft et al. [5] and a number of applications of the model to flows involving interfaces is shown.
Functions of Bounded Variation
Authors: Ambrosio Luigi , Fusco Nicola , Pallara Diego
Published: November 2023

This chapter is entirely devoted to functions of bounded variation and sets of finite perimeter. We have collected several results scattered in the literature, from classical ones up to recent developments, trying to give a self-contained and unified treatment of this topic. In particular, no prior knowledge of Sobolev spaces and weak derivatives is assumed, besides the basic terminology introduced in Section 2.2. Many proofs are obtained by blow-up arguments, and for this reason we use as much as possible the measure theoretic tools introduced in Chapter 2. We also deal from the beginning with realand vector-valued BV functions at the same time, because in some cases the vector case (see for instance Theorem 3.9) cannot be obtained from the scalar case arguing component by component; as a consequence we develop the whole theory without using the classical identification between real-valued BV functions and subgraphs of finite perimeter. Although this identification leads to a geometric understanding of the fine properties of BV functions and is of great importance in some applications (see for instance [11], [106], [237]), we omit it because this aspect of the theory is already well developed in other treatises, such as [152], [208] and [173].
Special Functions of Bounded Variation
Authors: Ambrosio Luigi , Fusco Nicola , Pallara Diego
Published: November 2023

The knowledge of the fine properties of functions of bounded variation and sets of finite perimeter presented in the previous chapter allows us to introduce and study the subspace SB V of special BV functions. These functions (defined as those BV functions whose Cantor part of derivative vanishes) have been singled out by E.
Minimum problems in Sobolev spaces
Authors: Braides Andrea , Defranceschi Anneliese
Published: November 2023

A fundamental tool for the application of the direct method of the calculus of variations to minimum problems for functionals defined on Sobolev spaces is the following well-known theorem (see e.g. Adams (1975)).
Loss of poly convexity by homogenization
Authors: Braides Andrea , Defranceschi Anneliese
Published: November 2023

In this chapter we discuss the structure of the ‘homogenized integrands ‘. It is clear that convexity is preserved by the passage to the ┌-limit, and hence also after homogenization, while the homogenized energy density is always quasiconvex. We will also show here that polyconvexity properties, in contrast, are not maintained by homogenization.
The functions of bHLH proteins
Authors: Littlewood Trevor D , Evan Gerard I
Published: November 2023

Most known bHLH proteins are transcriptional regulators. That is, they are proteins that are able to alter the genetic programme of cells by repressing or activating specific genes, often genes involved in control of growth and differentiation. Not surprisingly, therefore, inappropriate expression of genes encoding both bHLH and bHLHZ proteins is frequently, associated with tumorigenesis and/or developmental dysfunctions. bHLH proteins can be divided into two broad functional groups by their patterns of expression. In the first group, expression is restricted to cells of a particular lineage. These are sometimes referred to as ‘class B’ bHLH proteins and examples are the myogenic factors MyoD, MyfS, MRF4 and myogenin. The second group (‘class A’ bHLH prqteins) are expressed fairly ubiquitously. These proteins, for example the E12 transcription factor, typically form heterodimers with the lineage-specific bHLH proteins. A similar classification holds for the bHLHZ proteins. One group comprises members whose expression is either tissue-specific (e.g. the restricted expression of N-Myc [524, 732, 733]) or else correlated with a specific cellular state, for example c-Myc in proliferation, apoptosis and, in some cell types, the potential to differentiate (reviewed in [3, 25, 31, 39, 47, 49]). In order to function, members of this first group must dimerize with members of the second group of bHLHZ proteins which are ubiquitously expressed (e.g. the obligate interaction between the Myc proteins and the ubiquitous bHLHZ protein Max (reviewed in [3])). The functions of both classes of bHLH and bHLHZ proteins are reviewed in this section.
Introduction
Authors: Kirschke Heidrun , Barrett Alan J , Rawlings Neil D
Published: November 2023

Lysosomal cysteine proteinases are proteolytic enzymes that in their mature form are localized 1n lysosomes and the catalytic activity of which 1s based on a cysteine residue in the active site. They are synthesized as preproenzymes with molecular masses of 37 000-55 000 Da, and are processed to the mature, catalytically active enzymes with molecular masses of 23 000-30 000 Da.

Lysosomal cysteine proteinases catalyse the hydrolysis of peptide, amide, ester and thiol ester bonds. The mechanism of this hydrolysis is discussed in several reviews, e.g. [269]. The catalytic activity of these enzymes is dependent on pH values below 7 and the presence of reducing compounds.

The main in vivo function of the cysteine proteinases in lysosomes is the degradation of proteins that have been taken up by the cell or originate from other compartments of the same cell.
Cathepsin L (EC 3.4.22.15)
Authors: Kirschke Heidrun , Barrett Alan J , Rawlings Neil D
Published: November 2023

In 1971, Bohley and co-workers [1248] and, in 1972, Kirschke et al. [340] described a new enzyme from rat liver lysosomes which degraded proteins but not synthetic substrates. In 1974 the enzyme was named cathepsin L (in which 'L' stands for lysosomes) by the same authors [343, 1284]. ln 1976 and 1977 cathepsin L was characterized in detail by Kirschke and colleagues [169, 341]. At about the same time, Towatari and co-workers [285, 401] isolated a new cathepsin from rat liver lysosomes which also proved to be cathepsin L. The first indication that this enzyme might be involved in the process of malignant tumour growth came from work in 1978 on the precursor of cathepsin L called major excreted protein (l\1EP) by Gottesman [630]. The name cathepsin L (EC 3.4.22.15) was recommended by the nomenclature committee of IUB in 1978.
Other lysosomal cysteine proteinases
Authors: Kirschke Heidrun , Barrett Alan J , Rawlings Neil D
Published: November 2023

Some lysosomal cysteine proteinases that differ in their physical and catalytic properties from cathepsins B, H, L, K, Sand DPP I have been described. These enzymes have been named cathepsins T, N, 0 and fructose-1,6- bisphosphatase-converting enzyme. Amino acid sequence analysis revealed that cathepsin J [353] is identical to DPP I [368]. Cathepsin M [251,252,379,541] seems to be identical to cathepsin B by their similarity in size, carbohydrate and amino acid composition, pattern of peptides formed on digestion by trypsin [321] and catalytic properties [122]. The primary structures of cathepsin T and cathepsin N are not known yet. The enzyme from rat liver and kidney has a molecular mass of about 35 000 Da, and has the unique property among the lysosomal cysteine proteinases of converting the 52.5 kDa form of tyrosine aminotransferase to the 48 kDa form [49, 137, 138, 145, 327, 792].
Reaction with inhibitors
Authors: Kirschke Heidrun , Barrett Alan J , Rawlings Neil D
Published: November 2023

Cysteine proteinases contain a highly reactive cysteine residue in their active centre. They react readily with many thiol-blocking reagents, such as Hg2+ derivates, disulfides, heavy metal ions, iodoacetate and N-ethylmaleimide.

To achieve a more selective reaction with the enzymes rather than with SH-containing compounds generally, several peptidyl derivatives can be used. Compounds of this type can show selectivity amongst the cysteine proteinases. As will be shown in this section, nearly all of the synthesized cysteine proteinase inhibitors react (in some cases very weakly) with serine proteinases, with the exception of the epoxysuccinyl peptides. Selectivity amongst the individual cysteine proteinases has been obtained by variation of the peptidyl portion of the inhibitors, and in some cases (peptidyl-O-acyl hydroxamates and peptidyl-(acyloxy)methanes) also by modification of the leaving group.
Late response genes
Authors: Dudai Yadin
Published: November 2023

Similarly to *immediate early genes, late response genes (or simply ‘late genes’) is a term born in virology (Honess and Roizman 1974; Weinheimer and McKnight 1987). In mammalian cells, the expression of immediate early genes is detectable within minutes of stimulation, followed by the expression of delayed early genes, and finally, starting a few hours after stimulation, late response genes (Nathans et al. 1988; Lanahan et al. 1992). The latter encode a variety of proteins, including transcription factors,1 enzymes that produce other cellular products (biosynthetic enzymes), enzymes that degrade other proteins (proteases), and cytoskeletal elements.
Learning
Authors: Dudai Yadin
Published: November 2023

The multiplicity of dimensions clearly hints at the richness of the computational theories, neuronal algorithms and their cellular and molecular implementation, which one should expect to identify in neuronal circuits that learn. It also implies that a master solution to the mechanisms of learning is unlikely to exist.
Limbic system
Authors: Dudai Yadin
Published: November 2023

For example, the *hippocampus is a classical limbic structure, but is involved in functions that are characterized by more ‘neocortical-ness’ than ‘limbic-ness’; so are ‘limbic’ cortici (e.g. Suzuki et al. 1993).After so many viable years it is unlikely that the limbic system notion will suddenly disappear. It will probably give way to more sophisticated classifications of brain structure and function. But in that respect it does not differ from some other concepts of brain organization and function, that may reflect an artificial entity rather than a natural one (e.g. Kirkpatrick 1996).
Long-term potentiation
Authors: Dudai Yadin
Published: November 2023

In the field of memory research, interest in activity dependent lasting synaptic *plasticity is a natural sequel to the tenet that learning involves synaptic modifications. Over the years, cellular physiologists have identified a number of stimulation protocols that unveil synaptic plasticity (Johnston and Wu 1995). For example, in many types of synapses, when a pair of stimuli are delivered sequentially within a fraction of a second, the response to the second stimulus is larger than that to the first (del Castillo and Katz 1954). This is ‘paired-pulse facilitation’ (PPF).
Map
Authors: Dudai Yadin
Published: November 2023

Mappa is a cloth or napkin in Latin; yet the first maps were probably drawn not on cloth but rather on clay, by the Babylonians. In the neurosciences, the term is occasionally used in its everyday connotation (definition 2), to denote functional architecture and spatiotemporal activity patterns in discrete brain areas (e.g. in *functional neuroimaging), without necessarily making assumptions about the code and the fine properties of the map. This usage needs no further elaboration. But ‘map’ is also used more specifically in two different contexts or *levels of analysis. One refers to the mode of representation of sensorimotor space in neuronal space (definitions 3 and 4), the other to cognitive representation of the world (definition 5).
Mnemonics
Authors: Dudai Yadin
Published: November 2023

Mr Memory, Hitchcock’s master of facts, earned his living by performing feats of trivia pursuit in night clubs, while in parallel trusting to memory information for the sake of the notorious spy organization ‘39 Steps’ (Hitchcock 1935). Most mnemonists, both in fiction and in real life, are engaged in much more innocent activities. In modern times mnemonists are either regarded as curiosities or at most as interesting *subjects for research. But only a few centuries ago, mnemonists were still masters of an important and respectable art.
Ockham’s razor
Authors: Dudai Yadin
Published: November 2023

The term had originated from Greek palimpsestos, ‘scraped again’ (palin, again, psestos, scraped). It seems to have occurred first in the writings of the Roman poet Catullus (Hammond and Scullard 1970). When vellum was scarce, especially in the early middle ages, early manuscripts were erased and the writing material used again. As the removal of the original writing was seldom complete, valuable religious and classical texts have been recovered from such palimpsests (Lewis and Gibson 1900; Cuddon 1979; Shailor 1988).
Performance
Authors: Dudai Yadin
Published: November 2023

In behaving animals, the process or the outcome of learning are measured by monitoring changes in performance. But learning and performance are not equivalent. Learned information may remain latent until the appropriate conditions emerge for its expression as a change in performance (‘latent learning’; Tolman 1932). Earlier in the twentieth century, orthodox *behaviourists attempted to shy away from this common knowledge. They claimed that only overt behavioural acts (definition 3) are legitimate psychological data, whereas inferred implicit changes in the potential to behave are not.
Phase
Authors: Dudai Yadin
Published: November 2023

Phases (phasis, Greek for ‘appearance’) are distinct states in time and space. *Acquisition, *consolidation, retention, *retrieval, and *forgetting are all phases of memory. Some authors use the term ‘stage’ instead of phase to refer to these different periods of memory. ‘Phase’, however, is more suitable, because in addition to denoting a distinct state (definition 1), including in development (definition 2), it also connotes the recurrence of states (definition 3). This is important, because memory phases could recur.
Plasticity
Authors: Dudai Yadin
Published: November 2023

Plasticity is probably the most widely used term in modern neurobiology, clearly not to be recommended as an effective keyword in literature searches in this field. In its rudimentary form, the notion of plasticity as a vehicle for memory appears already in pre-scientific times: Socrates depicted memory as an impression on wax tablet, too hard in slow learners and over oft in the forgetful ones (Plato, Theaetetus). It is likely that this and similar *metaphors were used much earlier.
Protein synthesis
Authors: Dudai Yadin
Published: November 2023

The genetic code is decoded in all living cells in two major *phases. First it is transcribed from the DNA into a specific messenger RNA (mRNA) molecule. This process is termed ‘transcription’. The code is then read from the mRNA molecule to produce the copy of the corresponding protein. This process, which takes place in a complex cellular factory called ribosome, is termed ‘translation’. In practice, a group of ribosomes (‘polyribosome’) performs the task on each mRNA. There are many complex steps in protein synthesis (Alberts et al. 1994), but most of the details need not concern us here.
Real-life memory
Authors: Dudai Yadin
Published: November 2023

It may come as a surprise to postdocs running mice in water *mazes, poking molluscan neurons in a dish, or flashing computerized test icons in front of bored students—but memory does have a life outside the laboratory. It is this potential detachment from reality, particularly in dealing with human memory, that has prompted Neisser (1978) to deliver in the first International Conference on Practical Aspects of Memory a signal presentation, entitled ‘Memory: what are the important questions?’. Neisser claimed, more or less, that the bulk of experimental research on human memory, since its first days some one hundred years earlier (Ebbinghaus 1885), meant very little as much as memory in real life is concerned.
Introduction
Authors: Woessner J Frederick , Nagase Hideaki
Published: November 2023

It is a simple matter to trace the roots of this field. Although it had long been recognized that con nective tissue collagen was rapidly broken down in many physiological situations, such as bone remodelling, postpartum involution of the uterus and embrvogenesis, and in pathological process, such as decubitus ulcer, cancer and arthritis [1431, there was no evidence identifying the degradative factor(s) involved. Then in 1962, Gross and Lapiere [672] demonstrated that skin from the resorbing tail of the metamorphosing frog, when cultured on collagen gels, released an enzyme that could attack the triple-helix of collagen. This was a true collagenase that could digest collagen at neutral pH and 27 °C (well below the denaturation temperature of collagen). The same report also showed a similar activity produced by cultures of embryo skin, postpartum uterus and bone. In ret rospect, these last three activities were probably due to MMP-13.
Three-dimensional structures of the MMPs and TIMPs
Authors: Woessner J Frederick , Nagase Hideaki
Published: November 2023

The first three-dimensional (3D) structure of a metalloendopeptidase was reported for the thermophilic bacterial metalloproteinase thermolysin in 1972 by Mateukaryotic metalloendopeptidase was notthews et al. [1390]. The 3D structure of a eukaryotic metalloendopeptidase was not resolved until 1992 when Bode et al. [1347] reported the crystal structure of astacin from cray fish. The structure of astacin revealed that the topology around the catalytic zinc of the active site in this metalloproteinase can be superimposed on that of thermolysin, although the overall amino acid sequences of the two enzymes do not show a significant similarity [1347). Recent pro gress in determining the 3D structures of a number of metalloproteinases has revealed that the overall C”-backbone structure of astacin [19, 123, 1347] has a high degree of similarity with those of members of the other metalloproteinase families, i.e. snake venom metalloproteinases ada malysin II [1369, 1370) and atrolysin C [1421) in the reprolysin subfamily, MMPs in the matrixin subfamily (see below), and Pseudomonas aeruginosa alkaline proteinase [1342] and Serratia proteinase [1341] in the serralysin subfamily. Common structural elements are four parallel (sl, sII, s111, sV) and one antiparallel (slV) ,3-strands and three long a-helices (hA, hB, hC), which are arranged in an identical order (Fig. 4).
Changing Doxastic States: Two Complementary Perspectives
Authors: Rott Hans
Published: November 2023

In the last chapter we have seen how the analysis of knowledge may lead to the problem of belief revision. What one knows at a specific time instant does not only relate to what one believes at that instant, but also to a great variety of potential changes of the agent’s current beliefs. The relevance of the revision of beliefs to problems of epistemology provides an important reason for studying it.

In Chapter 1 we attended to what I called internal problems of belief. This has meant the task of drawing the right inferences on the basis of given information and expectations. If the task is successfully carried out, then the agent reaches a state of cognitive or reflective equilibrium. The present chapter is about problems caused by external interference. The influences from outside the doxastic system that we are going to consider come in two basic types. Agents may either learn new things or become doubtful about things that they used to think are true. Interaction with the world or with other agents may induce them to accept new items of belief, or to cease to accept old items of belief. In accordance with established terminology, I will say that doxastic states, as far as they are represented by belief bases or belief sets, are to be revised and/or contracted in response to new information. External influences are represented by discrete pieces of input to the doxastic system, which will in turn be represented by single input sentences of a given object language. Whether truth-conducive or not, such input first of all means a perturbation to a system that has previously been coherent. The addition of new beliefs frequently leads to a violation of the ideal of consistency, the subtraction of new beliefs violates the ideal of inferential closure.
Molecular biology databases
Authors: Kanehisa Minoru
Published: November 2023

The current state of biology is arguably comparable to seventeenth century physics in terms of the stage of formulating the science. Biology is still an empirical discipline with little formulation of basic principles that can be used in a deductive way to predict various biological phenomena. The technologies of genetics and cell biology, started in the nineteenth century, and of molecular biology, started in the twentieth century, have finally made it possible to gather fundamental observables in biology. It is expected that empirical rules similar to Kepler s laws and basic principles similar to Newton s theory will come along. This is where the computerized databases play critical roles as the basis of our expanding knowledge in biology.
Land of the Rising Sun
Authors: Hamilton W D
Published: November 2023

On a high hill top that overlooks Kyoto city, ancient capital of Japan, I watched free-living Japanese macaques for the first time. One of a crowd of scientific tourists, I had poured from a bus onto the flat, gravelled open space surrounding a kiosk and cafe that crown the hill and found the monkeys all around me. They gave us brief glances and moved quietly out of the way if we came near but much more they seemed to be watching the kiosk. Obviously they were free-living on this hilltop but right in this place could not be called exactly wild; however, the steep slopes over the edge of the small plateau were densely wooded and possibly the troupe obtained most of its food from there.
Cited but Little Read
Authors: Hamilton W D
Published: November 2023

Now comes a two-chapter break from disease and sex and a return to the topics that largely made up Volume 1 of Narrow Roads of Gene Land; but the present one is a very slight chapter. Sometimes it has seemed to me that the challenge to species and group-benefiting evolution issued in my first three papers has brought harpies to follow me ever since. Social behaviour, the topic of this and the next chapter, had been a four-year absolute obsession to me as I wrote the papers in the early 1960s—I was deeply immersed in it, a monomaniac, could do almost nothing else.
Two-Dimensional Problems Of Steady Motion
Authors: Hill R
Published: November 2023

In this and the two following chapters the ideas and techniques of Chapter VI a.re applied to the solution of a variety of problems of plane strain. We begin with problems of steady motion, in which the stress and velocitydo not vary at anyfixed point (referred to some coordinate system which may be at rest or moving uniformly). This condition is fulfilled in continuous processes of shaping metals, for example rolling, drawing, and extrusion. The approximation by the plastic-rigid body is likely to be good since the strains are usually large; the error due to the neglect of work-hardening can be largely removed by a simple correction factor, as we shall see. While the two-dimensional theory is strictly valid only for wide blocks or sheets, as in strip-rolling, it gives a useful qualitative picture of the deformation in such processes as the drawing of wire or the extrusion of rod; it will be shown, too, that the theoretical results, suitably modified, frequently provide a. close estimate of the energy consumption.
Mathematical Preliminaries
Authors: Chandrasekhar S
Published: November 2023

In this chapter, we shall provide an account of the analytical methods that lie at the base of much of the developments that are to be described in this book. These consist of Cartan’s calculus of differential forms and the tetrad and the Newman-Penrose formalisms. While none of these matters are novel in themselves, they cannot all be found in a coherent treatment in one place; and the account is included to make the book as self-contained as is possible. The presentation of the elements of differential geometry in §§2-6 is, however, not intended to replace the standard accounts of the subject available elsewhere: the presentation is confined to the barest essentials leading to Cartan’s equations of structure.
The Reissner-Nordstrom Solution
Authors: Chandrasekhar S
Published: November 2023

A spherically symmetric solution of the coupled equations of Einstein and of Maxwell is that of Reissner and Nordstrom. It represents a black hole with a mass M and a charge Q. Since one does not expect any macroscopic body to possess a net charge, the consideration of a charged black-hole would appear to be outside the realm of reality. Nevertheless, the study of the Reissner-Nordstrom solution contributes to our understanding of the nature of space and time. Thus, we shall find that the scattering of incident electromagnetic and gravitational waves by the Reissner-Nordstrom black hole is described by a symmetric unitary scattering-matrix of order four and allows for the partial conversion of energy of one kind (electromagnetic or gravitational) into energy of the other kind. Besides, the Reissner-Nordstrom solution provides a more general framework for the many surprising analytical features which we encountered in the study of the Schwarzschild solution in Chapter 4. And finally, the fact that the Reissner-Nordstrom solution has two horizons,
The Kerr Metric
Authors: Chandrasekhar S
Published: November 2023

In this chapter, we begin the study of the Kerr solution. It represents, as we have stated in the Prologue, the unique solution which the general theory of relativity provides for the description of all black holes that can occur in the astronomical universe by the gravitational collapse of stellar masses; and it is the only instance of a physical theory providing an exact description of a macroscopic object. In large measure, the preceding chapters are but preludes to the study we now begin.
Simple cases of electrification
Authors: Maxwell James Clerk
Published: November 2023

124.] We shall consider, in the first place, two parallel plane conducting surfaces of infinite extent, at a distance c from each other, maintained respectively at potentials A and B.

It is manifest that in this case the potential V will be a function of the distance z from the plane A, and will be the same for all points of any parallel plane between A and B, except near the boundaries of the electrified surfaces, which by the supposition are at an infinitely great distance from the point considered.
Confocal Quadric Surfaces*
Authors: Maxwell James Clerk
Published: November 2023

147.] Let the general equation of a confocal system be

(1)

where, λ is a variable parameter, which we shall distinguish by a suffix for the species of quadric, viz. we shall take λ.1 for the hyperboloids of two sheets, ‘A.2 for the hyperboloids of one sheet, and λ.3 for the ellipsoids. The quantities
Theory of conjugate functions in two dimensions,
Authors: Maxwell James Clerk
Published: November 2023

The number of independent cases in which the problem of electrical equilibrium has been solved is very small. The method of spherical harmonics has been employed for spherical conductors, and the methods of electrical images and of inversion are still more powerful in the cases to which they can be applied. The case of surfaces of the second degree is the only one, as far as I know, in which both the equipotential surfaces and the lines of force are known when the lines of force are not plane curves.
Electrolysis
Authors: Maxwell James Clerk
Published: November 2023

255.] I Have already stated that when an electric current in any part of its circuit passes through certain compound substances called Electrolytes, the passage of the current is accompanied by a certain chemical process called Electrolysis, in which the substance is resolved into two components called Ions, of which one, called the Anion, or the electronegative component, appears at the Anode, or place where the current enters the electrolyte, and the other, called the Cation, appears at the Cathode, or the place where the current leaves the electrolyte.
Conduction In Three Dimensions
Authors: Maxwell James Clerk
Published: November 2023

285.] At any point let an element of area dS be taken normal to the axis of x, and let Q units of electricity pass across this area from the negative to the positive side in unit of time, then, if becomes ultimately equal to u when dS is indefinitely diminished, u is said to be the Component of the electric current in the direction of x at the given point.

In the same way we may determine v and w, the components of the current in the directions of y and z respectively.
Conduction in dielectrics
Authors: Maxwell James Clerk
Published: November 2023

325.] We have seen that when electromotive force acts on a dielectric medium it produces in it a state which we have called electric polarization, and which we have described as consisting of electric displacement within the medium in a direction which, in isotropic media, coincides with that of the electromotive force, combined with a superficial charge on every element of volume into which we may suppose the dielectric divided, which is negative on the side towards which the force acts, and positive on the side from which it acts.
The measurement of electric resistance
Authors: Maxwell James Clerk
Published: November 2023

In the present state of electrical science, the determination of the electric resistance of a conductor may be considered as the cardinal operation in electricity, in the same sense that the determination of weight is the cardinal operation in chemistry.
Intuitionistic modal logics
Authors: Gabbay Dov M
Published: November 2023

This chapter deals with fibring modality into intuitionistic logic. The key difference between fibring modality into modal logic (to form a bi-modal logic) and fibring modality into intuitionistic logic is that in the latter case we are fibring into a logic whose semantics requires a condition of persistence.
Applications of self-fibring
Authors: Gabbay Dov M
Published: November 2023

To get an intuitive idea of what kind of modal operators are involved, consider the expression Soon A. In temporal setting this means 'A will be true soon’. The meaning of Soon may be time dependent itself. In ancient times Soon could mean within three months, while in modern times Soon can mean within a few days.
Conditional implications and non-monotonic consequence
Authors: Gabbay Dov M
Published: November 2023

Gabbay put forward his case for his system 𝕔 using proof-theoretic considerations. Makinson [1989] proposed a semantics for Gabbay’s logic and showed completeness. Makinson also studied the properties of the consequence relations associated with many well-known non-monotonic systems. Kraus et al [1990] used the preferential semantics of Shoham [1987; 1988] to give semantics for a family of axiomatic extensions of Gab- bay’s C logic for the language of classical logic. Thus a new area of research activity has emerged, namely the syntactic and semantic study of non-monotonic logics through their consequence relations.
combining temporal logic systems
Authors: Gabbay Dov M
Published: November 2023

In this chapter we are interested in describing systems in which two distinct temporal ‘points of view’ coexist. Descriptions of temporal systems under a single point of view, i.e. one-dimensional temporal systems, abound in the literature. These one-dimensional temporal logics differ from each other in several ways. They differ in the form the logic is presented, whether a proof theoretical, model theoretical or algebraic presentation. They differ in the ontology of time adopted, whether time is to be represented as a set of points, intervals or events. They can also differ in the properties assigned to flows of time, whether linear or branching time, discrete or dense, continuous or allowing for gaps. In this chapter we consider both proof- and model-theoretical presentations of temporal logics on a point-based ontology. Most of the results presented assume that the flow of time is linear.
Fibring implication logics
Authors: Gabbay Dov M
Published: November 2023

The proof-theoretical side of our investigations into fibred semantics can be formulated as follows: how can we combine different proof systems into more general ones, possibly preserving the desirable properties of the originals? We expect semantically based methods, e.g. semantic tableau methods, to play a crucial role in developing suitable proof methods based on fibred semantics.
Products of modal logics
Authors: Gabbay Dov M
Published: November 2023

Let F1 = (W1, R1),F2 = (W2, R2) be two Kripke frames describing two independent systems of possible worlds (or ‘states ‘). Suppose we need to construct a complex frame F combining them both.
Fibring modal tableaux
Authors: Gabbay Dov M
Published: November 2023

In the previous chapter we studied under which conditions proof systems are well suited for fibring, and we argued that labelled tableaux are calculi of this kind. In Chapters 14 and 15 we have shown how D‘Agostino and Mondadori ‘s 1994 classical proof system KE, a combination of tableaux and natural deduction inference rules which allows for a restricted (‘analytic‘) use of the cut rule, can be extended to deal with fibred logics, in particular for a combination of modal and substructural logics and the combination of different fragment of substructural implications.
Fibring labelled deductive systems
Authors: Gabbay Dov M
Published: November 2023

We saw in previous chapters how fibring can be done with the instrumental use of labels. This chapter applies our fibring ideas to labelled deductive systems (LDS). LDS (see [Gabbay, 1996b]) is a general methodology for presenting and studying logical systems. It unifies many areas of logic and has extensive applications.