November 30, 2006, 9:33 PM CT

Importance of Archiology

Often archaeology provides the only means to learn of the existence and behaviors of people in the past. A number of thousands of cultures and societies and millions of people have come and gone across the millennia of which there simply is little or no written record - no history - or for which written records may be misrepresentative or incomplete. Writing as it is known and understood today did not exist anywhere in the world until about 5000 years ago, and only spread among a relatively small number of technologically advanced civilisations. In contrast Homo sapiens have existed for at least 200,000 years, and other species of Homo for millions of years (see Human evolution). These civilisations are, not coincidentally, the best-known; they have been open to the inquiry of historians for centuries, while the study of pre-historic cultures has arisen only recently. Even within a civilisation that is literate at some levels, a number of important human practices are not officially recorded. Any knowledge of the formative early years of human civilisation - the development of agriculture, cult practices of folk religion, the rise of the first cities - must come from archaeology.

Even where written records do exist, they are invariably incomplete or biased to some extent. In a number of societies, literacy was restricted to the elite classes, such as the clergy or the bureaucracy of court or temple. The literacy even of an aristocracy has sometimes been restricted to deeds and contracts. The interests and world-view of elites are often quite different from the lives and interests of the rest of the populace. Writings that were produced by people more representative of the general population were unlikely to find their way into libraries and be preserved there for posterity. Thus, written records tend to reflect the biases, assumptions, cultural values and possibly deceptions of a limited range of individuals, commonly only a fraction of the larger population. As such, written records cannot be trusted as a sole source. The material record is nearer to a fair representation of society, though it is subject to its own inaccuracies, such as sampling bias and differential preservation.........

Posted by: William      Permalink

November 30, 2006, 4:53 AM CT

World's Oldest Ritual Discovered

A startling archaeological discovery this summer changes our understanding of human history. While, up until now, scholars have largely held that mans first rituals were carried out over 40, 000 years ago in Europe, it now appears that they were wrong about both the time and place.

Associate Professor Sheila Coulson, from the University of Oslo, can now show that modern humans, Homo sapiens, have performed advanced rituals in Africa for 70,000 years. She has, in other words, discovered mankinds oldest known ritual.

The archaeologist made the surprising discovery while she was studying the origin of the Sanpeople. A group of the San live in the sparsely inhabited area of north-western Botswana known as Ngamiland.

Coulson made the discovery while searching for artifacts from the Middle Stone Age in the only hills present for hundreds of kilometers in any direction. This group of small peaks within the Kalahari Desert is known as the Tsodilo Hills and is famous for having the largest concentration of rock paintings in the world.

The Tsodilo Hills are still a sacred place for the San, who call them the Mountains of the Gods and the Rock that Whispers.

The python is one of the Sans most important animals. As per their creation myth, mankind descended from the python and the ancient, arid streambeds around the hills are said to have been created by the python as it circled the hills in its ceaseless search for water.........

Posted by: William      Permalink         Source

November 30, 2006, 4:22 AM CT

First-Ever Stem Cell Transplant In Human Brain

Neurosurgeons and physicians at Doernbecher Children's Hospital, Oregon Health & Science University, Nov. 14, performed the first transplant of purified human fetal neural stem cells into the brain of a study participant with neuronal ceroid lipofuscinosis (NCL), also known as Batten disease. NCL is a rare and fatal neurodegenerative disorder that affects infants and children.

The transplant is the focus of a Phase 1 clinical trial to evaluate the safety and preliminary efficacy of HuCNS-SC(TM) - a proprietary human central nervous stem cell product developed by StemCells, Inc., Palo Alto, Calif. This one-year trial will involve up to six children with NCL.

"Doernbecher's specialists are privileged to care for this child and family and to push forward groundbreaking work in degenerative brain diseases," said co-principal investigator Nathan Selden, M.D., Ph.D., F.A.C.S., F.A.A.P., who performed the surgery. "Our team is pleased that our patient's recovery thus far has been as expected".

The research team will continue to concentrate their efforts on the health and well-being of the study participant and family and will, along with Stem Cells, Inc., provide periodic updates as appropriate until the trial is completed.

In the interest of confidentiality, the research team requests that all parties avoid interfering with the study participant and family during recovery from surgery.........

Posted by: Sean      Permalink         Source

November 29, 2006, 9:39 PM CT

Save the whales? Sure, but how many?

How many wildebeest should live in the Serengeti" How many grizzly bears should call Yellowstone home" Are there too few tigers in the world" Conservationist biologists grapple with the task of setting population targets for the species they are trying to protect a decision steeped in politics, emotion, and sometimes, science.

In a new paper appearing in the journal Bioscience, the New York-based Wildlife Conservation Society (WCS) examines the current hodgepodge of population target levels (PTLs) being used by wildlife managers, and proposes a simpler, four-tiered system to measure conservation success. The paper cataloged 18 different approaches currently used to set PTLs, and showed the diverse ways in which they apply to national laws and international treaties.

According to the paper's author, WCS ecologist Dr. Eric Sanderson, 'minimum viable populations' the goal commonly used by wildlife managers that aims to have self-sustaining populations should be seen as the beginning, not the end, of conservation.

'People want much more from wild animals than to see them just persist: we want animals to interact with their environment, evolve over time, be beautiful and useful to us, and to satisfy ethical teachings regarding respect for nature,' said Dr. Sanderson.........

Posted by: Ashley      Permalink         Source

November 29, 2006, 9:34 PM CT

Preserve Fertility After Cancer

The Center for Reproductive Research at Northwestern University is launching a new, experimental research program for young women who may be at risk to lose their ovarian function and fertility following therapy for cancer.

The program, in which a woman's ovary is removed and frozen for possible future use, is being led by Teresa Woodruff, Ph.D., associate director of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University and executive director of the Institute for Women's Health Research at Northwestern's Feinberg School of Medicine. The long-term goal of the program is to be able to extract and mature eggs from cryopreserved (frozen) ovarian tissues to initiate pregnancies once cancer therapy has been completed.

"This breakthrough may permit not only the potential preservation of fertility options for women and girls with cancer, but also can be applied to normal in vitro fertilization patients. This procedure, when developed, could radically change the way infertility is viewed, reduce and eliminate embryo storage and provide better options for women who do not respond to hormonal treatment, " said Woodruff.

In recognition of the Cancer Center's commitment to providing fertility options to women and men with cancer, it has been recognized as a Fertile Hope Center of Excellence, the fifth medical center in the country to receive this designation. Fertile Hope is a non-profit organization that assists cancer patients faced with infertility.........

Posted by: Sean      Permalink         Source

November 29, 2006, 5:02 AM CT

Predicting Outcome of Child Heart Surgery

Georgia Tech and Emory University scientists have developed an innovative new technology that will help pediatric cardiac surgeons design and test a customized surgical procedure before they ever pick up a scalpel. With a better understanding of each child's unique heart defect, surgeons could greatly improve the likelihood that children with complex defects requiring multiple surgeries over a period of several years could have smoother recoveries and an improved quality of life after their operations.

The technology, known as image-based surgical planning and developed with the help of pediatric heart specialists and pediatric surgeons at The Children's Hospital of Philadelphia (CHOP) and Emory University, creates a three-dimensional model of the child's heart with data from the child's MRI scans at different times in the cardiac cycle, also called a 4D MRI. The models allow surgeons to visualize the direction of blood flow and determine any energy loss in the heart. So if a surgeon were planning a certain correction to an area of a child's heart, a model created by the system would show the surgeon how well blood would flow through the newly configured heart.

The goal of the Georgia Tech/Emory project is to create a complete system that allows surgeons to get a detailed look at the child's heart functions with the new MRI system, design surgical procedures for optimum post-operative performance and evaluate the heart's performance with a sophisticated blood flow computer simulation.........

Posted by: Kevin      Permalink         Source

November 29, 2006, 4:25 AM CT

Don't Understand Prescription Medicine Labels?

When Michael Wolf paged though dusty, yellowing pharmacists logs from the 1890s at the Smithsonian National Museum of American History, he found the following entry about a druggists encounter with a confused patient: Shake well, a patient apparently read out loud to the pharmacist from his prescription bottle label. Does that mean I shake myself".

It sounds like the punch line of a bad joke, but it wasnt. And the confusion experienced by that patient more than a century ago hasnt changed much.

Many people still dont fully understand the seemingly simple label instructions on their prescription medication, according to a new study of low-income patients by Wolf, Ph.D., assistant professor of medicine at Northwestern Universitys Feinberg School of Medicine. The study was published Nov. 29 online in Annals of Internal Medicine (www.anals.org). Wolf is presenting a position piece on how to improve those labels Nov. 29 at the American College of Physicians Foundation conference in Washington, D.C.

Wolf found that nearly half of the patients in the study misinterpreted at least one or more out of the five prescription labels they were shown. Patients with low literacy made the most mistakes and frequently were unable to grasp four out of five label instructions. But even people with a high-school education and higher had problems.........

Posted by: Sean      Permalink         Source

November 28, 2006, 8:58 PM CT

Solar Brightness And Global Warming

Changes in the Sun's brightness over the past millennium have had only a small effect on Earth's climate, according to a review of existing results and new calculations performed by researchers in the United States, Switzerland, and Germany.

The review, led by Peter Foukal (Heliophysics, Inc.), appears in the September 14 issue of Nature. Among the coauthors is Tom Wigley of the National Center for Atmospheric Research. NCAR's primary sponsor is the National Science Foundation.

"Our results imply that, over the past century, climate change due to human influences must far outweigh the effects of changes in the Sun's brightness," says Wigley.

Reconstructions of climate over the past millennium show a warming since the 17th century, which has accelerated dramatically over the past 100 years. Many recent studies have attributed the bulk of 20th-century global warming to an increase in greenhouse gas concentrations in the atmosphere. Natural internal variability of Earth's climate system may also have played a role. However, the discussion is complicated by a third possibility: that the Sun's brightness could have increased.

The new review in Nature examines the factors observed by astronomers that relate to solar brightness. It then analyzes how those factors have changed along with global temperature over the last 1,000 years.........

Posted by: Tyler      Permalink         Source

November 28, 2006, 8:18 PM CT

First ever Gamma Ray Clock

Astronomers using the H.E.S.S. telescopes have discovered the first ever modulated signal from space in Very High Energy Gamma Rays - the most energetic such signal ever observed. Regular signals from space have been known since the 1960s, when the first radio pulsar (nicknamed Little Green Men-1 for its regular nature) was discovered. This is the first time a signal has been seen at such high energies - 100,000 times higher than previously known - and is reported today (24th November) in the Journal Astronomy and Astrophysics.

The signal comes from a system called LS 5039 which was discovered by the H.E.S.S. team in 2005. LS5039 is a binary system formed of a massive blue star (20 times the mass of the Sun) and an unknown object, possibly a black hole. The two objects orbit each other at very short distance, varying between only 1/5 and 2/5 of the separation of the Earth from the Sun, with one orbit completed every four days.

"The way in which the gamma ray signal varies makes LS5039 a unique laboratory for studying particle acceleration near compact objects such as black holes." Explained Dr Paula Chadwick from the University of Durham, a British team member of H.E.S.S.

Different mechanisms can affect the gamma-ray signal that reaches Earth and by seeing how the signal varies, astronomers can learn a great deal about binary systems such as LS 5039 and also the effects that take place near black holes.........

Posted by: Brooke      Permalink         Source

November 28, 2006, 7:45 PM CT

World's Smallest Piano Wire

Scientists from Delft University of Technology and FOM Foundation have successfully made and 'tuned' the world's smallest piano wire. The wires are made of carbon nanotubes that measure approximately 2 nanometers in diameter. The scientists have published an article on the subject this week in the scientific journal Nano Letters.

The scientists at the Kavli Institute of Nanoscience Delft and the FOM Foundation (Fundamental Research on Matter) made the small wires from carbon nanotubes, measuring approximately 1 micrometer long and approximately 2 nanometres in diameter. The tubes were attached to electrodes and initially placed above a layer of silicon oxide. This layer of silicon oxide was then partially etched away with acid, which caused the tubes to detach and hang.

A layer of silicon is contained beneath the silicon oxide. A strong and frequently variable alternating current is applied to this layer, which causes the hanging nanotubes to vibrate. The suspended tube is alternately attracted and repelled. The largest measured deviation for one tube was 8 nanometres. The distance of the nanotubes to the layer of silicon influences the electrical capacity to the layer of silicon. The movement of the nanowires is derived from these changes in capacity.

When the frequency of the applied current approaches the level of the suspended tube's eigenfrequency, it begins to vibrate more powerfully. The order of magnitude of these frequencies amounts to a few tens of MHz. By varying the strength and frequency of the applied current, the research group led by Professor Herre van der Zant succeeded in transposing the wire from a freely suspended state, to a state in which it is taut and vibrates. Van der Zant: "And as such it is like tightening a piano wire or guitar string. You can, as it were, tune the wire".........

Posted by: Kevin      Permalink         Source