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Curious Cat Science and Egineering blog full tag cloud
An Introductory Science Curriculum for 21st Century Biologists by David Botstein (webcast)
Very good look at future of biology education.
Related: MIT Faculty Study Recommends Significant Undergraduate Education Changes - The Importance of Science Education - Webcast: Engineering Education in the 21st Century - Educating the Engineer of 2020: NAE Report
In degenerative disorders like macular degeneration and retinitis pigmentosa, outer-layer cells, called photoreceptors, break down in the early stages of disease, leading to loss of vision. Extensive research has focused on replacing these cells, in an effort to restore sight. In people with advanced disease or blindness, however, the inner cell layers may also break down or become disorganized and need to be rebuilt, says Rose.
“The outer retina is like the CPU, and the inner retina is like the motherboard,” he says. “If I attach a new CPU to a dead motherboard, it won’t do any good, no matter how great a CPU it is.”
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In lower vertebrates like fish and chickens, retinal cells are known to generate new neurons in response to damage, often restoring sight. While mammals do not have the same self-healing capacity, some previous research has suggested that under particular circumstances, mammals’ retinas might be able to generate new neurons.
Related: A Journey Into the Human Eye - How Brain Resolves Sight - The Subtly Different Squid Eye - 3-D Images of Eyes
Photograph by Dr Tin-Yam Chan, University of Keelung
This squat lobster, found in waters 150 meters (492 feet) deep, is one of the new species. Eighty percent of the world’s species remain to be discovered, notes French scientist Philippe Bouchet, one of the expedition’s leaders.
A World of Crabs from One Tiny Island
Related: Most Dinosaurs Remain Undiscovered - Ocean Life - Huge Gorilla Population Found in Congo - Still Just a Lizard - 50 Species of Diatoms
Harvard researchers gain new insight into aging
Scientists have long known that aging causes gene expression to change, and DNA damage to accumulate. But now, research led by Harvard Medical School scientists explains the connection between the two processes in mammals.
The paper, published in the journal Cell, found that a multi-tasking protein called SIRT1 that normally acts as guardian of the genome gets dragged away to DNA fix-it jobs. When the protein abandons its normal post to work as a genetic handyman, order unravels elsewhere in the cell. Genes that are normally under its careful watch begin to flip on.
“What this paper actually implies is that aspects of aging may be reversible,” said David Sinclair, a Harvard Medical School biologist who led the research. “It sounds crazy, but in principle it should be possible to restore the youthful set of genes, the patterns that are on and off.”
The study is just the latest to draw yet more attention to sirtuins, proteins involved in the aging process
Aging is fascinating. By and large people just accept it. We see it happen to those all around us, without exception. But what causes biological aging? It is an interesting area of research.
Related: lobsters show no apparent signs of aging - Our Genome Changes as We Age - Millennials in our Lifetime? - Radical Life Extension - posts on cells
Discovery of Giant Roaming Deep Sea Protist Provides New Perspective on Animal Evolution
Biologist Mikhail “Misha” Matz and his colleagues recently discovered the grape-sized protists and their complex tracks on the ocean floor near the Bahamas. DNA analysis confirmed that the giant protist found by Matz and his colleagues in the Bahamas is Gromia sphaerica, a species previously known only from the Arabian Sea.
Matz says the protists probably move by sending leg-like extensions, called pseudopodia, out of their cells in all directions. The pseudopodia then grab onto mud in one direction and the organism rolls that way, leaving a track. Hr says the giant protists’ bubble-like body design is probably one of the planet’s oldest macroscopic body designs, which may have existed for 1.8 billion years.
“I personally think now that the whole Precambrian may have been exclusively the reign of protists,” says Matz. “Our observations open up this possible way of interpreting the Precambrian fossil record.”
He says the appearance of all the animal body plans during the Cambrian explosion might not just be an artifact of the fossil record. There are likely other mechanisms that explain the burst-like origin of diverse multicellular life forms.
Single-Celled Giant Upends Early Evolution
A distant relative of microscopic amoebas, the grape-sized Gromia sphaerica was discovered once before, lying motionless at the bottom of the Arabian Sea. But when Mikhail Matz of the University of Texas at Austin and a group of researchers stumbled across a group of G. sphaerica off the coast of the Bahamas, the creatures were leaving trails behind them up to 50 centimeters (20 inches) long in the mud.
The trouble is, single-celled critters aren’t supposed to be able to leave trails. The oldest fossils of animal trails, called ‘trace fossils’, date to around 580 million years ago, and paleontologists always figured they must have been made by multicellular animals with complex, symmetrical bodies.
Related: Lancelet Genome Provides Answers on Evolution - MicroRNAs Emerged Early in Evolution - Fossils of Sea Monster - Sea Urchin Genome
Cool invention helps tired players bounce back
It’s also a proven athletic performance enhancer - billed as better than steroids without any ill effects.
“We use the Glove primarily for health reasons,” said Dan Garza, the 49ers’ medical director. “But outside of sports, it has potential for a lot of exciting things. This technology is a much more effective way of cooling the core temperature than what we would typically do - misting, fanning, cold towels, fluids.”
The Glove works by cooling the body from inside out, rather than conventional approaches that cool from outside in. The device creates an airtight seal around the wrist, pulls blood into the palm of the hand and cools it before returning it to the heart and to overheated muscles and organs. The palm is the ideal place for rapid cooling because blood flow increases to the hands (and feet and face) as body temperature rises.
“These are natural mammalian radiators,” said Dennis Grahn, who invented the device with Stanford colleague Craig Heller.
Cool, you can buy your own for only $2,000 
(The Glove used to be called Core Control) High resolution image. Related: Research on Reducing Hamstring Injuries - The Science of the Football Swerve - Randomization in Sports - posts on science and athletics
| Paul Rothemund, scientist at Cal Tech, provides a interesting look at DNA folding and DNA based algorithmic self-assembly. In the talk he shows the promise ahead for using biological building blocks using DNA origami — to create tiny machines that assemble themselves from a set of instructions.
Algorithmic Self-Assembly of DNA Sierpinski Triangles, PLoS paper. I posted a few months ago about how you can participate in the protein folding, with the Protein Folding Game. Related: Viruses and What is Life - DNA Seen Through the Eyes of a Coder - Synthesizing a Genome from Scratch - Evidence of Short DNA Segment Self Assembly - Scientists discover new class of RNA |
The webcast goes into the human eye while describing the microscopic details of the human eye. See more such videos: The Eyes of a Fly - Zoom Into a Fish - Zoom Into a Butterfly
Related: Non-Newtonian Fluid Demo - posts on biology - science webcasts
General Biology Course at University of California - Berkeley, Fall 2007. Instructors John Forte, R Fischer and R Malkin. “General introduction to cell structure and function, molecular and organism genetics, animal development, form and function. Intended for biological sciences majors, but open to all qualified students.” A great service from Berkeley with video and audio… Topics include: Macromolecules structure and function, How cells function-an introduction to cellular metabolism and biological catalysts, Microbes - Viruses, Bacteria, Plasmids, Transposons and Homeostasis: The body’s defenses.
Related: Science and Engineering Webcast Directory - Harvard Course: Understanding Computers and the Internet - Berkeley and MIT courses online - Arizona State Science Studio Podcasts - Google Tech Talks
The world’s smallest species of snake, Leptotyphlops carlae, with adults averaging just under 4 inches in length, has been identified on the Caribbean island of Barbados. The species — which is as thin as a spaghetti noodle and small enough to rest comfortably on a U.S. quarter — was discovered by Blair Hedges, an evolutionary biologist at Penn State.
Hedges determined that the Barbados species is new to science on the basis of its genetic differences from other snake species and its unique color pattern and scales. He also determined that some old museum specimens that had been misidentified by other scientists actually belong to this new species.
Scientists use adults to compare sizes among animals because the sizes of adults do not vary as much as the sizes of juveniles and because juveniles can be harder to find. In addition, scientists seek to measure both males and females of a species to determine its average size. Using these methods, Hedges determined that this species, is the smallest of the more than 3,100 known snake species.
According to Hedges, the smallest and largest species of animals tend to be found on islands, where species can evolve over time to fill ecological niches in habitats that are unoccupied by other organisms. Those vacant niches exist because some types of organisms, by chance, never make it to the islands. For example, if a species of centipede is missing from an island, a snake might evolve into a very small species to “fill” the missing centipede’s ecological niche.
In contrast to larger species — some of which can lay up to 100 eggs in a single clutch — the smallest snakes, and the smallest of other types of animals, usually lay only one egg or give birth to one offspring. Furthermore, the smallest animals have young that are proportionately enormous relative to the adults. For example, the hatchlings of the smallest snakes are one-half the length of an adult, whereas the hatchlings of the largest snakes are only one-tenth the length of an adult. The Barbados snake is no exception to this pattern. It produces a single slender egg that occupies a significant portion of the mother’s body.
Related: Smart Squirrels Sneaky Snake Strategy - posts on evolution - posts on reptiles - Evolution in Darwin’s Finches - cat spies snake
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