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of time. But it seems as though the rate of climate change is accelerating, and I'll talk more about that, next time … Published 27 November 2012 © 2013 Karl S. Kruszelnicki Pty Ltd |
Black holes growing faster than expected Black hole find Existing theories on the relationship between the size of a galaxy and its central black hole are wrong according to a new Australian study. The discovery by Dr Nicholas Scott and Professor Alister Graham, from Melbourne's Swinburne University of Technology, found smaller galaxies have far smaller black holes than previously estimated. Central black holes, millions |
to billions of times more massive than the Sun, reside in the core of most galaxies, and are thought to be integral to galactic formation and evolution. However astronomers are still trying to understand this relationship. Scott and Graham combined data from observatories in Chile, Hawaii and the Hubble Space Telescope, to develop a data base listing the masses of 77 galaxies and their |
central supermassive black holes. The astronomers determined the mass of each central black hole by measuring how fast stars are orbiting it. Existing theories suggest a direct ratio between the mass of a galaxy and that of its central black hole. "This ratio worked for larger galaxies, but with improved technology we're now able to examine far smaller galaxies and the current theories don't |
hold up," says Scott. In a paper to be published in the Astrophysical Journal, they found that for each ten-fold decrease in a galaxy's mass, there was a one hundred-fold decrease in its central black hole mass. "That was a surprising result which we hadn't been anticipating," says Scott. The study also found that smaller galaxies have far denser stellar populations near their centres |
than larger galaxies. According to Scott, this also means the central black holes in smaller galaxies grow much faster than their larger counterparts. Black holes grow by merging with other black holes when their galaxies collide. "When large galaxies merge they double in size and so do their central black holes," says Scott. "But when small galaxies merge their central black holes quadruple in |
size because of the greater densities of nearby stars to feed on." Somewhere in between The findings also solve the long standing problem of missing intermediate mass black holes. For decades, scientists have been searching for something in between stellar mass black holes formed when the largest stars die, and supermassive black holes at the centre of galaxies. "If the central black holes in |
smaller galaxies have lower mass than originally thought, they may represent the intermediate mass black hole population astronomers have been hunting for," says Graham. "Intermediate sized black holes are between ten thousand and a few hundred thousand times the mass of the Sun, and we think we've found several good candidates." "These may be big enough to be seen directly by the new generation |
Hoodoos may be seismic gurus Hoodoo prediction Towering chimney-like sedimentary rock spires known as hoodoos may provide an indication of an area's past earthquake activity. The research by scientists including |
Dr Rasool Anooshehpoor, from the United States Nuclear Regulatory Commission, may provide scientists with a new tool to test the accuracy of current hazard models. Hoodoo formations are often found |
in desert regions, and are common in North America, the Middle East and northern Africa. They are caused by the uneven weathering of different layers of sedimentary rocks, that leave |
boulders or thin caps of hard rock perched on softer rock. By knowing the strengths of different types of sedimentary layers, scientists can determine the amount of stress needed to |
cause those rocks to fracture. The United States Geological Survey (USGS) use seismic hazard models to predict the type of ground motion likely to occur in an area during a |
seismic event. But, according to Anooshehpoor, these models lack long term data. "Existing hazard maps use models based on scant data going back a hundred years or so," says Anooshehpoor. |
"But earthquakes have return periods lasting hundreds or thousands of years, so there is nothing to test these hazard models against." The researchers examined two unfractured hoodoos within a few |
kilometres of the Garlock fault, which is an active strike-slip fault zone in California's Red Rock Canyon. Their findings are reported in the Bulletin of the Seismological Society of America. |
"Although we can't put a precise age on hoodoos because of their erosion characteristics, we can use them to provide physical limits on the level of ground shaking that could |
potentially have occurred in the area," says Anooshehpoor. The researchers developed a three-dimensional model of each hoodoo and determined the most likely place where each spire would fail in an |
earthquake. They then tested rock samples similar to the hoodoo pillars to measure their tensile strength and compared their results with previously published data. USGS records suggest at least one |
large magnitude earthquake occurred along the fault in the last 550 years, resulting in seven metres of slip, yet the hoodoos are still standing. This finding is consistent with a |
median level of ground motion associated with the large quakes in this region, says Anooshehpoor. "If an earthquake occurred with a higher level of ground motion, the hoodoos would have |
collapsed," he says. "Nobody can predict earthquakes, but this will help predict what ground motions are associated with these earthquakes when they happen." Dr Juan Carlos Afonso from the Department |
of Earth and Planetary Sciences at Sydney's Macquarie University says it's an exciting development. "In seismic hazard studies, it's not just difficult to cover the entire planet, it's hard to |
cover even small active regions near populated areas," says Afonso. "You need lots of instruments, so it's great if you can rely on nature and natural objects to help you." |
Now, it is common knowledge these days that Hitler's final great offensive in the last years of WWII was the Ardennes Offensive of 1944/45, also known as the battle of the Bulge. What was not appreciated at the time by the Allied high command was just how desperately short of vital supplies the Third Reich armies actually were. The Ardennes Offensive was Hitler's bold |
attempt to capture and hold the Allied army's massive supply of Brussels sprouts, vital - of course - for the full functioning of any army. German intelligence were aware that the American army was - in particular - massing huge quantities of the vital Brussels sprouts just behind their frontlines in preparedness for their own massive push - and - of course - in |
time for Christmas. The German's audacious plan would have succeeded if the Allies had not quickly worked out that it was their stockpiles of Brussels sprouts that were under immediate threat. The bold plan put forward by the Allied Generals was a heavy gamble, but it paid off. They ordered their front-line chefs to begin boiling their entire stocks of Brussels sprouts, and - |
most importantly - to keep them boiling well past a state of fully preparedness. So, when the weather altered and the wind direction changed, it blew the smell of over-cooked Brussels sprouts straight into the faces of the advancing Germans. Then the Reich troops knew that they would not be able to replenish their stocks of Brussels sprouts and any sprouts that they did |
capture from the Allied frontline kitchens would be overcooked to the point of inedibility. Later in this series, we will discuss the major strategic role that Brussels sprouts have played in world history, such as Hadrian building a wall to protect the Roman Empire's most northern supplies of Brussels sprouts from the northern barbarians, thus thwarting the barbarian's fiendish plan to deep-fry the Roman's |
entire stockpiles of sprouts. Then there was, also, Napoleon's retreat from Moscow when his over-long supply line of Brussels sprouts direct from France broke down. Even when his troops could get sprouts, they were of poor quality - dry, wizened and frozen solid. Of course, this led to a massive collapse of morale. Eventually, the lack of good quality sprouts forced a massive retreat |
where thousands of French troops died from a pitiful lack of sprouts. And, of course, not forgetting - of course - how the Spanish conquest of the Americas was a result of the Spaniards overwhelming sprout superiority. |
Books Yellow, Red, and Green and Blue, All true, or just as good as true, And here's the Blue Book just for YOU! Hard is the path from A to Z, And puzzling to a curly head, Yet leads to Books—Green, Yellow and Red. For every child should understand That |
letters from the first were planned To guide us into Fairy Land So labour at your Alphabet, For by that learning shall you get To lands where Fairies may be met. And going where this pathway goes, You too, at last, may find, who knows? The Garden of the Singing |
Rose. As to whether there are really any fairies or not, that is a difficult question. The Editor never saw any himself, but he knew several people who have seen them-in the Highlands-and heard their music. If ever you are in Nether Lochaber, go to the Fairy Hill, and you |
may hear the music your-self, as grown-up people have done, but you must go on a fine day. This book has been especially re-published to raise funds for: The Great Ormond Street Hospital Children’s Charity By buying this book you will be donating to this great charity that does so |
much good for ill children and which also enables families to stay together in times of crisis. And what better way to help children than to buy a book of fairy tales. Some have not been seen in print or heard for over a century. 33% of the Publisher’s profit |
from the sale of this book will be donated to the GOSH Children’s Charity. YESTERDAYS BOOKS for TODAYS CHARITIES LITTLE RED RIDING HOOD Once upon a time there lived in a certain village a little country girl, the prettiest creature was ever seen. Her mother was excessively fond of her; |
and her grandmother doted on her still more. This good woman had made for her a little red riding-hood; which became the girl so extremely well that everybody called her Little Red Riding-Hood. One day her mother, having made some custards, said to her: "Go, my dear, and see how |
thy grandmamma does, for I hear she has been very ill; carry her a custard, and this little pot of butter." Little Red Riding-Hood set out immediately to go to her grandmother, who lived in another village. As she was going through the wood, she met with Gaffer Wolf, who |
had a very great mind to eat her up, but he dared not, because of some faggot-makers hard by in the forest. He asked her whither she was going. The poor child, who did not know that it was dangerous to stay and hear a wolf talk, said to him: |
"I am going to see my grandmamma and carry her a custard and a little pot of butter from my mamma." "Does she live far off?" said the Wolf. "Oh! aye," answered Little Red Riding-Hood; "it is beyond that mill you see there, at the first house in the village." |
"Well," said the Wolf, "and I'll go and see her too. I'll go this way and you go that, and we shall see who will be there soonest." The Wolf began to run as fast as he could, taking the nearest way, and the little girl went by that farthest |
about, diverting herself in gathering nuts, running after butterflies, and making nosegays of such little flowers as she met with. The Wolf was not long before he got to the old woman's house. He knocked at the door—tap, tap. "Your grandchild, Little Red Riding-Hood," replied the Wolf, counterfeiting her voice; |
"who has brought you a custard and a little pot of butter sent you by mamma." The good grandmother, who was in bed, because she was somewhat ill, cried out: "Pull the bobbin, and the latch will go up."The Wolf pulled the bobbin, and the door opened, and then presently |
he fell upon the good woman and ate her up in a moment, for it was above three days that he had not touched a bit. He then shut the door and went into the grandmother's bed, expecting Little Red Riding-Hood, who came some time afterward and knocked at the |
door—tap, tap. Little Red Riding-Hood, hearing the big voice of the Wolf, was at first afraid; but believing her grandmother had got a cold and was hoarse, answered: "’Tis your grandchild, Little Red Riding-Hood, who has brought you a custard and a little pot of butter mamma sends you." The |
Wolf cried out to her, softening his voice as much as he could: "Pull the bobbin, and the latch will go up." Little Red Riding-Hood pulled the bobbin, and the door opened. The Wolf, seeing her come in, said to her, hiding himself under the bed-clothes: "Put the custard and |
the little pot of butter upon the stool, and come and lie down with me." Little Red Riding-Hood undressed herself and went into bed, where, being greatly amazed to see how her grandmother looked in her night-clothes, she said to her: "Grandmamma, what great arms you have got!" "That is |
the better to hug thee, my dear." "Grandmamma, what great legs you have got!" "That is to run the better, my child." "Grandmamma, what great ears you have got!" "That is to hear the better, my child." "Grandmamma, what great eyes you have got!" "It is to see the better, |
my child." "Grandmamma, what great teeth you have got!" "That is to eat thee up." And, saying these words, this wicked wolf fell upon Little Red Riding-Hood, and tried to start eating her. Red Riding Hood screamed “Someone Help Me!” over and over again. The woodcutter, who was felling trees |
nearby, heard Red Riding Hood’s screams for help and ran to the cottage. He burst in to find the wolf trying to eat Red Riding Hood. He swung his axe, and with one blow killed the bad wolf for which Red Riding Hood was ever so grateful. Great Book! Really |
interesting read! Was great to see a published version of Jewish tales! Arrived very quickly too - great service! A thrilling book about a chase across the US! A great story, my son loved it! Quick and Convenient delivery! Stories of the famous spice route across Asia! Great to see |
a volume of Phillipine Folklore Stories in Print, only one I've found on the web! We deliver to destinations all over the world, and here at Abela, we have some of the best rates in the book industry. We charge shipping dependant on the book you have ordered and where |
in the world you are ordering from. This will be shown below the price of the book. The delivery time is typically dependant on where in the world you are ordering from, Should you need a estimated delivery time, please do not hesitate to contact us. We pride ourselves on |
the quality of our packaging and damage rates are very low. In the unlikely event there is damage please contact us before returning your item, as you may have to pay for return shipping, if you have not let us know. Due to the nature of books being read then |
What exactly does "desecration" mean? Is it just flag burning — or does it also include smearing the flag with dirt? How about dropping it on the ground? And why should law enforcement get to decide who to arrest for such desecration? Free expression and the right to dissent are among the core principles which the American flag represents. The First Amendment must be |
protected most when it comes to unpopular speech. Failure to do so fails the very notion of freedom of expression. Our democracy is strong because we tolerate all peaceful forms of expression, no matter how uncomfortable they make us feel, or how much we disagree. If we take away the right to dissent - no matter how unpopular - what freedom will be sacrificed |
next? Make a Difference Your support helps the ACLU defend free speech and a broad range of civil liberties. Burn the Flag or Burn the Constitution? (2011 blog): Sadly, Congress is once again considering an amendment to the U. S. Constitution banning desecration of the American flag and, in doing so, testing our political leaders' willingness to defend what is arguably one of America's |
most sacred principles — protecting political speech. Flag Amendment Defeated, First Amendment Stands Unscathed (2003): On June 27, 2006, the Senate voted down the proposed Flag Desecration Amendment by the slimmest margin ever. The vote was 66-34, just one vote short of the two-thirds needed to approve a constitutional amendment. Reasons to Oppose the Flag Desecration Amendment (2004 resource): Talking Points on Opposing the |
First, an object is placed on the platform of the printer upon – a petrie dish for example. Then the printer must check the height of the object to make sure everything is calibrated correctly. Mr. Carvalho placed a paper card on the platform of the 3D-Bioplotter to demonstrate how the machine works. Mr. Carvalho then talked us through the printing process. To begin, |
a liquefied material – in this case a silicone paste – is pressed through a needle-like tip by applying air pressure. The needle moves in all three dimensions which means it is able to create a three dimensional object. The printer is called ‘Bioplotter’ because the unique aspect of this machine is its use of biomaterials to make implants or other objects for biomedical |
application. Some of the implants which are made using the 3D Bioplotter are intended to dissolve in the body. The materials which are used in this application include PLLA, PLGA, and silicone. Implants made with thermoplastics – as they are mostly water and CO2 – are removed by the body naturally in around a week or two. Other materials, such as ceramic paste, may |
also be used to print implants. The implants printed using ceramic paste do not dissolve. Instead, the body uses this material to create new bone. This actually speeds up the process of the body’s regeneration. The 3DBioplotter also prints hydrogels – such as collagen or alginate. These materials can have human cells actually added to them. Thus human cells may be printed directly with |
this machine. Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has thrilled us at Adafruit with its passion and dedication to making solid objects from digital models. Recently, we have noticed that our community integrating electronics projects into 3D printed enclosures, brackets, and sculptures, so each Thursday we celebrate and highlight these bold pioneers! Have you take considered building a |
3D project around an Arduino or other microcontroller? How about printing a bracket to mount your Raspberry Pi to the back of your HD monitor? And don’t forget the countless EL Wire and LED projects that are possible when you are modeling your projects! The Adafruit Learning System has dozens of great tools to get you well on your way to creating incredible works |
of engineering, interactive art, and design with your 3D printer! If you have a cool project you’ve made that joins the traditions of 3D printing and electronics, be sure to send it in to be featured here! |
Re-inventing the Planned City Monday, March 12, 2012 TAU and MIT launch pilot project to re-think 50's era "New Towns" A bird's-eye view of Kiryat Gat In response to population growth, many "new towns" or planned cities were built around |
the world in the 1950s. But according to Dr. Tali Hatuka, head of Tel Aviv University's Laboratory for Contemporary Urban Design (LCUD) at the Department of Geography and the Human Environment, these cities are a poor fit for modern lifestyles |
— and it's time to innovate. TAU has launched a pilot project, in collaboration with a team from the Massachusetts Institute of Technology led by Prof. Eran Ben-Joseph, to revitalize this aging model. Last month, a team of five TAU |
and 11 MIT graduate students visited Kiryat Gat, a mid-sized town in the south of Israel. Home to branches of industrial giants Hewlett-Packard Company and Intel, Kiryat Gat was chosen as a "laboratory" for re-designing outmoded planned civic spaces. Based |
on smart technologies, improved transportation, use of the city's natural surroundings, and a reconsideration of the current use of city space, the team's action plan is designed to help Kiryat Gat emerge as a new, technologically-advanced planned city — a |
prototype that could be applied to similar urban communities. Planning a future for the mid-sized city The project, jointly funded by TAU's Vice President for Research and MIT's MISTI Global Seed Funds, will create a new planning model that could |
reshape the future of Kiryat Gat and similar cities across the world which are often overlooked in academia and practical planning. "Our goal is to put a spotlight on these kinds of towns and suggest innovative ways of dealing with |
their problems," says TAU student Roni Bar. MIT's Alice Shay, who visited Israel for the first time for the project, believes that Kiryat Gat, a city that massive urbanization has left behind, is an ideal place for the team to |
make a change. "The city is at a catalyst point — an exciting moment where good governance and energy will give it the capacity to implement some of these new projects." To tackle the design and planning challenges of the |
city, the team of students focused on four themes: the "mobile city," which looked at transport and accessibility; the "mediated city," dealing with technological infrastructure; the "compact city," which reconsidered the use of urban space and population growth; and the |
"natural city," which integrated environmental features into the urban landscape. Finding common ground Ultimately, the team’s goal is to create a more flexible city model that encourages residents and workers to be a more active part of the urban fabric |
of the city, said Dr. Hatuka. The current arrangement of dedicated industrial, residential, and core zones is out of step with a 21st century lifestyle, in which people work, live, and spend their leisure time in the same environment. "Much |
of the past discourse about the design of sustainable communities and 'eco-cities' has been premised on using previously undeveloped land," says Prof. Ben-Joseph. "In contrast, this project focuses on the 'retrofitting' of an existing environment — a more likely approach, |
given the extent of the world's already-built infrastructure." The students from TAU and MIT have become a truly cohesive team, and their diversity of background helps challenge cultural preconceptions, Bar says. "They ask many questions that help us to rethink |
things we took for granted." Shay agrees. "Tali and Eran have created an incredible collaboration, encouraging us all to exchange ideas. Our contexts are different but there is a common urban design language." The team estimates that they will be |
able to present the updated model of the city early next year. The next step is further exploring the project's key themes at a March meeting at MIT. And while the project has provided an exceptional educational experience for all |
involved, ideas are already leaping off the page and into the city's urban fabric. "In the next two months, the Mayor of Kiryat Gat would like to push this model forward and implement the initial steps that we have offered," |
Elderly people are at increased risk of food-borne illness because as they age, their immune systems become weaker. In fact, the website for the Centers for Disease Control estimates that each year about 48 million people get sick, 128,000 are |
hospitalized and 3,000 die from food-borne diseases. The most severe cases tend to occur in the very old. The good news is that food poisoning can be prevented if you follow proper home food safety practices. Ruth Frechman, a registered |
dietitian and spokesperson for the American Dietetic Association, spoke with AgingCare.com about home food safety for elderly people. "Since older adults are at particular risk for food-borne illness, good food safety habits are extremely crucial." Ms. Frechman says three common |
cooking and food preparation mistakes can result in unsafe food and potential food poisoning. Bacteria in raw meat and poultry juices can be spread to other foods, utensils and surfaces. . "To prevent cross-contamination, keep raw foods separate from ready-to-eat |
foods and fresh vegetables," she says. "For example, use two cuttings boards: one strictly for raw meat, poultry and seafood; the other for ready-to-eat foods like breads and vegetables." She recommends washing cutting boards thoroughly in hot soapy water after |
each use or placing them in the dishwasher. Use a bleach solution or other sanitizing solution and rinse with clean water. Always wash your hands after handling raw meat. Leaving food out too long Leaving food out too long at |
room temperature can cause bacteria to grow to dangerous levels that can cause illness. "Many people think it's okay to leave food sitting out for a few hours," Ms. Frechman says. "But that's a dangerous habit. Food should not be |
left out for more than two hours. And if it's over 90 degrees, like at an outdoor summer barbecue, food should not be out for more than one hour." Its common knowledge that meat should be cooked to proper temperatures. |
However, most people don't know that even leftovers that were previously cooked should be re-heated to a certain temperature. Ms. Frechman says re-heating foods to the proper temperature can kill many harmful bacteria. Leftovers should be re-heated to at least |
165 degrees Fahrenheit. "Harmful bacteria are destroyed when food is cooked to proper temperatures," she says. "That's why a food thermometer comes in handy not only for preparing food, but also for re-heating." How long it is safe to eat |
leftovers? Not as long as you would think, Ms. Frechman says. Chicken, fish and beef expire after three to four days in the refrigerator. To help seniors track if leftovers are still good, she recommends writing the date on the |
package of leftovers. Seniors and their caregivers should take these preventive measures to avoid germs in food and contracting food poisoning. Pay attention to the foods that are eaten, how food is prepared, and properly maintain the food in the |
What is HIV? And what is AIDS? Find answers to some common questions in this section. How is HIV transmitted - and how is it not transmitted? Find out the answers in this section. Worried you might have HIV? Have an HIV test - it's the only way to know |
for sure. HIV treatment is not a cure, but it is keeping millions of people well. Start learning about it in this section. In this section we have answered some of the questions you might have if you have just found out you have HIV. Find healthcare services and support. |
A series of illustrated leaflets designed to support conversations between professionals and people with HIV. Our award-winning series of patient information booklets. Each title provides a comprehensive overview of one aspect of living with HIV. Twice-monthly email newsletter on the practical aspects of delivering HIV treatment in resource-limited settings. Our |
regular newsletter, providing in-depth discussion of the latest research across the HIV sector. Free to people personally affected by HIV. Find contact details for over 3000 key organisations in more than 190 countries An instant guide to HIV & AIDS in countries and regions around the world The most comprehensive |
listing of HIV-related services in the UK Pre-exposure prophylaxis (PrEP) – free webinar 18 April 2013As part of its European HIV prevention work, NAM is collaborating... Learning the basics about hepatitis C 05 April 2013If you are familiar with NAM’s patient information materials, hopefully you... Treatment as prevention – free |
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