Author Archives: curiouscat

Microbes Flourish In Healthy People

Bugs Inside: What Happens When the Microbes That Keep Us Healthy Disappear? by Katherine Harmon

The human body has some 10 trillion human cells—but 10 times that number of microbial cells. So what happens when such an important part of our bodies goes missing?

“Someone who didn’t have their microbes, they’d be naked,” says Martin Blaser, a professor of microbiology and chair of the Department of Medicine at New York University Langone Medical Center in New York City.

Even though it is such an apparently integral and ancient aspect of human health, scientists are still grasping for better ways to study human microbiota—before it changes beyond historical recognition. Borrowing models from outside of medicine has helped many in the field gain a better understanding of this living world within us. “The important concept is about extinctions,” Blaser says. “It’s ecology.”

The first step in understanding these systems is simply taking stock of what archaea, bacteria, fungi, protozoa and viruses are present in healthy individuals. This massive micro undertaking has been ongoing since 2007 through the National Institutes of Health’s (NIH) Human Microbiome Project. So far it has turned up some surprisingly rich data, including genetic sequencing for some 205 of the different genera that live on healthy human skin.

Despite the flood of new data, Foxman laughs when asked if there is any hope for a final report from the Human Microbiome Project any time soon. “This is the very, very beginning,” she says, comparing this project with the NIH’s Human Genome Project, which jump-started a barrage of new genetic research. “There are basic, basic questions that we don’t know the answers to,” she says, such as how different microbiota are between random individuals or family members; how much microbiota change over time; or how related the microbiota are to each other on or inside a person’s body.

Related: Microcosm by Carl ZimmerTracking the Ecosystem Within UsAlligator Blood Provides Strong Resistance to Bacteria and VirusesBeneficial Bacteria

Presidential Science Teaching and Mentoring Awards

Related: President Obama Speaks on Getting Students Excited About Science and EngineeringPresidential Awards for Excellence in Science, Mathematics and Engineering MentoringFund Teacher’s Science Projects$12.5 Million from NSF For Educating High School Engineering Teachers

Remarks by President Obama on the “Educate to Innovate” Campaign and Science Teaching and Mentoring Awards, January 6, 2010

To all the teachers who are here, as President, I am just thrilled to welcome you, teachers and mentors, to the White House, because I believe so strongly in the work that you do. And as I mentioned to some of you, because I’ve got two girls upstairs with math tests coming up, I figure that a little extra help from the best of the best couldn’t hurt. So you’re going to have assignments after this. (Laughter.) These awards were not free. (Laughter.)

photo of President Obama with science teachers at the White HousePresident Barack Obama with Presidential Awards for Excellence in Mathematics and Science Teaching winners in the State Dining of the White House January 6, 2010. (Official White House photo by Chuck Kennedy)

We are here today to honor teachers and mentors like Barb who are upholding their responsibility not just to the young people who they teach but to our country by inspiring and educating a new generation in math and science. But we’re also here because this responsibility can’t be theirs alone. All of us have a role to play in building an education system that is worthy of our children and ready to help us seize the opportunities and meet the challenges of the 21st century.

Whether it’s improving our health or harnessing clean energy, protecting our security or succeeding in the global economy, our future depends on reaffirming America’s role as the world’s engine of scientific discovery and technological innovation. And that leadership tomorrow depends on how we educate our students today, especially in math, science, technology, and engineering.

But despite the importance of education in these subjects, we have to admit we are right now being outpaced by our competitors. One assessment shows American 15-year-olds now ranked 21st in science and 25th in math when compared to their peers around the world. Think about that — 21st and 25th. That’s not acceptable. And year after year the gap between the number of teachers we have and the number of teachers we need in these areas is widening. The shortfall is projected to climb past a quarter of a million teachers in the next five years — and that gap is most pronounced in predominately poor and minority schools.

And meanwhile, other nations are stepping up — a fact that was plain to see when I visited Asia at the end of last year. The President of South Korea and I were having lunch, and I asked him, what’s the biggest education challenge that you have? He told me his biggest challenge in education wasn’t budget holes, it wasn’t crumbling schools — it was that the parents were too demanding. (Laughter.) He’s had to import thousands of foreign teachers because parents insisted on English language training in elementary school. The mayor of Shanghai, China — a city of over 20 million people — told me that even in such a large city, they had no problem recruiting teachers in whatever subject, but particularly math and science, because teaching is revered and the pay scales are comparable to professions like doctors.
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Fungus-gardening Ant Species Has Given Up Sex Completely

The complete asexuality of a widespread fungus-gardening ant, the only ant species in the world known to have dispensed with males entirely, has been confirmed by a team of Texas and Brazilian researchers.

photo of christian rabeling excavating ants in BrazilGraduate student Christian Rabeling excavating fungus-farming ant nests in Brasilia.

Most social insects—the wasps, ants and bees—are relatively used to daily life without males. Their colonies are well run by swarms of sterile sisters lorded over by an egg-laying queen. But, eventually, all social insect species have the ability to produce a crop of males who go forth in the world to fertilize new queens and propagate.

Queens of the ant Mycocepurus smithii reproduce without fertilization and males appear to be completely absent, report Christian Rabeling, Ulrich Mueller and their Brazilian colleagues in open access journal PLoS ONE this week.

“Animals that are completely asexual are relatively rare, which makes this is a very interesting ant,” says Rabeling, an ecology, evolution and behavior graduate student at The University of Texas at Austin. “Asexual species don’t mix their genes through recombination, so you expect harmful mutations to accumulate over time and for the species to go extinct more quickly than others. They don’t generally persist for very long over evolutionary time.”

Previous studies of the ants from Puerto Rico and Panama have pointed toward the ants being completely asexual. One study in particular, by Mueller and former graduate student Anna Himler (now at Arizona State University), showed that the ants reproduced in the lab without males, and that no amount of stress induced the production of males.

Scientists believed that specimens of male ants previously collected in Brazil in the 1960s could be males of M. smithii. If males of the species existed, it would suggest that—at least from time to time—the ants reproduce sexually.

Rabeling analyzed the males in question and discovered that they belonged to another closely related (sexually reproducing) species of fungus-farmer, Mycocepurus obsoletus, thus establishing that no males are known to exist for M. smithii. He also dissected reproducing M. smithii queens from Brazil and found that their sperm storage organs were empty.

Taken together with the previous studies of the ants, Rabeling and his colleagues have concluded that the species is very likely to be totally asexual across its entire range, from Northern Mexico through Central America to Brazil, including some Caribbean islands.

As for the age of the species, the scientists estimate the ants could have first evolved within the last one to two million years, a very young species given that the fungus-farming ants evolved 50 million years ago.

Rabeling says he is using genetic markers to study the evolution and systematics of the fungus-gardening ants and this will help determine the date of the appearance and genetic mechanism of asexual reproduction more precisely in the near future.

Full press release

Related: Bdelloid Rotifers Abandoned Sex 100 Million Years AgoAmazonian Ant Species is All Female, Reproduces By CloningFemale Sharks Can Reproduce AsexualityAmazon Molly Fish are All Female

Sumatran Tiger and Cubs Filmed by Remote Wildlife Monitoring Cameras

Video cameras installed in the Sumatran jungle in Indonesia have captured close-up footage of a tiger and two cubs. This is the first time that the World Wildlife Fund has recorded evidence of tiger breeding in central Sumatra in what should be prime tiger habitat.

The Sumatran Tiger is the smallest of all surviving tiger subspecies. Male Sumatran tigers average 204 cm (6 feet, 8 inches) in length from head to tail and weigh about 136 kg (300 lb).

Analysis of DNA is consistent with the hypothesis that the Sumatran Tigers have been isolated after a rise in sea level at the Pleistocene to Holocene border (about 12,000-6,000 years ago) from other tiger populations. The Sumatran Tiger is genetically isolated from all living mainland tigers.

Wouldn’t it be nice to see the photos those tigers could take with the awesome cat cam?

Related: Bukit Tiga Puluh National ParkUsing Cameras Monitoring To Aid Conservation EffortsRare Saharan Cheetahs PhotographedJaguars Back in the Southwest USA

Arduino: Open Source Programmable Hardware

Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It’s intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments.

Arduino can sense the environment by receiving input from a variety of sensors and can affect its surroundings by controlling lights, motors, and other actuators. The microcontroller on the board is programmed using the Arduino programming language and the Arduino development environment.

The boards can be built by hand or purchased preassembled; the software can be downloaded for free. The hardware reference designs (CAD files) are available under an open-source license, you are free to adapt them to your needs.

See the getting started guide to try for yourself.

Related: Home Engineering: Physical Gmail NotifierSelf Re-assembling Robots
Lego Mindstorms Robots Solving: Sudoku and Rubik’s CubeBabbage Difference Engine In Lego

Printing Bone, Muscle and More

A Pittsburgh-based research team has created and used an innovative ink-jet system to print “bio-ink” patterns that direct muscle-derived stem cells from adult mice to differentiate into both muscle cells and bone cells.

The custom-built ink-jet printer, developed at Carnegie Mellon’s Robotics Institute, can deposit and immobilize growth factors in virtually any design, pattern or concentration, laying down patterns on native extracellular matrix-coated slides (such as fibrin). These slides are then placed in culture dishes and topped with muscle-derived stem cells (MDSCs). Based on pattern, dose or factor printed by the ink-jet, the MDSCs can be directed to differentiate down various cell-fate differentiation pathways (e.g. bone- or muscle-like).

“This system provides an unprecedented means to engineer replacement tissues derived from muscle stem cells,” said Johnny Huard, professor of orthopedic surgery at the University of Pittsburgh School of Medicine and director of the Stem Cell Research Center at Children’s Hospital of UPMC. Huard has long-standing research findings that show how muscle-derived stem cells (MDSCs) from mice can repair muscle in a model for Duchenne Muscular Dystrophy, improve cardiac function following heart failure, and heal large bone and articular cartilage defects.

Weiss and Campbell, along with graduate student Eric Miller, previously demonstrated the use of ink-jet printing to pattern growth factor “bio-inks” to control cell fates. For their current research, they teamed with Phillippi, Huard and biologists of the Stem Cell Research Center at Children’s Hospital to gain experience in using growth factors to control differentiation in populations of MDSCs from mice.

The team envisions the ink-jet technology as potentially useful for engineering stem cell-based therapies for repairing defects where multiple tissues are involved, such as joints where bone, tendon, cartilage and muscle interface. Patients afflicted with conditions like osteoarthritis might benefit from these therapies, which incorporate the needs of multiple tissues and may improve post-treatment clinical outcomes.

The long-term promise of this new technology could be the tailoring of tissue-engineered regenerative therapies. In preparation for preclinical studies, the Pittsburgh researchers are combining the versatile ink-jet system with advanced real-time live cell image analysis developed at the Robotics Institute and Molecular Biosensor and Imaging Center to further understand how stem cells differentiate into bone, muscle and other cell types.

Related: Engineer Tried to Save His Sister and Invented a Breakthrough Medical DeviceNanoparticles With Scorpion Venom Slow Cancer SpreadVery Cool Wearable Computing Gadget from MITFunding Medical Research

Albatross Chicks Fed Plastic Ocean Pollution by Parents

photo of dead Albatross chick

See more photographs of remains of albatross chicks on the Midway Atoll, a tiny stretch of sand and coral near the middle of the North Pacific.

The nesting babies are fed bellies-full of plastic by their parents, who soar out over the vast polluted ocean collecting what looks to them like food to bring back to their young. On this diet of human trash, every year tens of thousands of albatross chicks die on Midway from starvation, toxicity, and choking.

To document this phenomenon as faithfully as possible, none of the plastic in any of these photographs was moved, placed, manipulated, arranged, or altered in any way. These images depict the untouched stomach contents of baby birds in one of the world’s most remote marine sanctuaries, more than 2000 miles from the nearest continent.

Related: Dead Zones in the OceanVast Garbage Float in the Pacific OceanSharpshinned HawkBiodegradable Plastic Bags and Bottles2,000 Species New to Science from One Island

Graduate Engineering and Professional Education @UMichigan

Dilbert’s bosses broke the video link (so I removed it) – not a good sign that they will succeed in my eyes. If they can’t follow basic web usability guidelines it doesn’t make me want to spend time on them.

Engineering TV is a site with lots of good webcasts for engineers: “by engineers for engineers! Focused on technical B2B engineering topics”. In the embedded webcast Dr. Ann Marie Sastry, Director of the Energy Systems Engineering Program at the University of Michigan, discusses a collaboration between GM and the University of Michigan in the Interdisciplinary Graduate Engineering and Professional Education Programs. This is a good example of university and business collaboration.

Related: Directory of site with science and engineering webcastsScience Postercastsposts on engineering educationScience and Engineering Lectures from VideoLectures.Netprevious post on Engineering TV

Prion Proteins, Without Genes, Can Evolve

‘Lifeless’ prion proteins are ‘capable of evolution’

scientists transferred prion populations from brain cells to other cells in culture and observed the prions that adapted to the new cellular environment out-competed their brain-adapted counterparts. When returned to the brain cells, the brain-adapted prions again took over the population.

Charles Weissmann, head of Scripps Florida’s department of infectology who led the study, said: “On the face of it, you have exactly the same process of mutation and adaptive change in prions as you see in viruses.

“This means that this pattern of Darwinian evolution appears to be universally active. “In viruses, mutation is linked to changes in nucleic acid sequence that leads to resistance.

“Now, this adaptability has moved one level down- to prions and protein folding – and it’s clear that you do not need nucleic acid (DNA or RNA) for the process of evolution.”

He said: “The prion protein is not a clone, it is a quasi-species that can create different protein strains even in the same animal. “The abnormal prion proteins multiply by converting normal prion proteins.

“The implication of Charles Weissmann’s work is that it would be better to cut off that supply of normal prion proteins rather than risk the abnormal prion adapting to a drug and evolving into a new more virulent form.

Related: Challenging the Science Status QuoClues to Prion InfectivitySoil Mineral Degrades the Nearly Indestructible PrionBdelloid Rotifers Abandoned Sex 100 Million Years Ago