Category Archives: Science

The Eagle Has Landed

Neil Armstrong and Buzz Aldren land on the moon: July 20, 1969. As Neil Armstrong took humanity’s first step onto the Moon he said:

That’s one small step for man, one giant leap for mankind.

The Science Behind Hummingbird Flight

Aerodynamics of the hovering hummingbird

Hummingbirds and insects have evolved for sustained hovering ï¬‚ight from vastly different ancestral directions, and their distinct phylogenies underlie the differences in their aerodynamic styles. In all other birds—and, presumably, hummingbird ancestors—the downstroke provides 100% of weight support during slow ï¬‚ight and hovering. Given that many birds possess the mass-speciï¬c power (using anaerobic metabolism) to hover for short periods, the selective pressure on hummingbird ancestors was probably for increased efï¬ciency (resulting in stiff wings with greatly simpliï¬ed
kinematics), and an upstroke muscle (the supracoracoideus) that makes the recovery stroke rapid, while contributing enough to the hovering power requirements to allow the downstroke muscle (the pectoralis) to operate within its aerobic limits.

In other words, this pseudosymmetrical wingbeat cycle is good enough, and although hummingbirds do not exhibit the elegant aerodynamic symmetry of insects, natural selection rewards ‘good enough’ as richly as it does our aesthetic ideals

A single spot in the Sahara that provides huge amounts of nutrients to the Amazon

The BodÃ©lÃ© depression: a single spot in the Sahara that provides most of the mineral dust to the Amazon forest

About 40 million tons of dust are transported annually from the Sahara to the Amazon basin. Saharan dust has been proposed to be the main mineral source that fertilizes the Amazon basin, generating a dependence of the health and productivity of the rain forest on dust supply from the Sahara. Here we show that about half of the annual dust supply to the Amazon basin is emitted from a single source: the BodÃ©lÃ© depression located northeast of Lake Chad, approximately 0.5% of the size of the Amazon or 0.2% of the Sahara. Placed in a narrow path between two mountain chains that direct and accelerate the surface winds over the depression, the BodÃ©lÃ© emits dust on 40% of the winter days, averaging more than 0.7 million tons of dust per day.

Even understanding how connected the global ecosystem is, research like this provides amazing reminders of those connections.

Great Webcast Explaining the Digestive Systems

You will learn things like why it is so important to chew your food well (increase the surface area for enzymes to get at the food). Our bodies also have adapted to provide a huge surface area for the digestive system to work; the small intestine alone has a surface area of 250 square meters (larger than the size of most apartments). Your small intestine is 4.5 to 10.5 meters long.

Domestic Cats Remain Successful Predators

House cats kill more critters than thought by Elizabeth Weise

While only 30% of roaming house cats kill prey — two animals a week on average — they are still slaying more wildlife than previously believed, according to research from the University of Georgia.
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The cats brought home just under a quarter of what they killed, ate 30% and left 49% to rot where they died.

The carnage cuts across species. Lizards, snakes and frogs made up 41% of the animals killed, Loyd and fellow researcher Sonia Hernandez found. Mammals such as chipmunks and voles were 25%, insects and worms 20% and birds 12%.
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Seeking a window into the hidden lives of cats, the researchers recruited 60 owners in the Athens, Ga., area. Each owner put a small video camera mounted on a break-away collar on the cat in the morning and let the cat out, then removed the camera and downloaded the footage each night.

Interesting data. As I wrote about before you can get your very own cat cam and see what your cat is up to. I posted an interview I did with the engineer that designs and sells the cat cams.

Virus Kills Breast Cancer Cells in Laboratory

Some very exciting and good news from Penn State. Researchers have found a virus that kills breast cancer cells. It is great to read about research breakthroughs like this. Of course, most of these announcements never become practical solutions, unfortunately. And if they do it is many many years later and almost always in much less exciting ways than the headlines. Still, the percentage that do make it through the process into workable solutions provide us great benefits.

Virus kills breast cancer cells in laboratory

Adeno-associated virus type 2 (AAV2) is a virus that regularly infects humans but causes no disease. Past studies by the same researchers show that it promotes tumor cell death in cervical cancer cells infected with human papillomavirus. Researchers used an unaltered, naturally occurring version of AAV2 on human breast cancer cells.

“Breast cancer is the most prevalent cancer in the world and is the leading cause of cancer-related death in women,” said Samina Alam, research associate in microbiology and immunology. “It is also complex to treat.”
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“We can see the virus is killing the cancer cells, but how is it doing it?” Alam said. “If we can determine which viral genes are being used, we may be able to introduce those genes into a therapeutic. If we can determine which pathways the virus is triggering, we can then screen new drugs that target those pathways. Or we may simply be able to use the virus itself.”
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AAV2 does not affect healthy cells. However, if AAV2 were used in humans, the potential exists that the body’s immune system would fight to remove it from the body. Therefore, by learning how AAV2 targets the death pathways, researchers potentially can find ways to treat the cancer without using the actual virus.

In ongoing studies, the Penn State researchers also have shown AAV2 can kill cells derived from prostate cancer, mesothelioma, squamous cell carcinoma, and melanoma. A fourth line of breast cancer cells — representing the most aggressive form of the disease — also was studied in a mouse breast tumor model, followed by treatment with AAV2. Preliminary results show the destruction of the tumors in the mice, and researchers will report the findings of those mouse studies soon.

The fight against cancer has many promising breakthroughs. We have made some great progress. Still the fight is extremely difficult and we have many more frustrations than successes.

Physical Activity for Adults: Inactivity Leads to 5.3 Million Early Deaths a Year

Obviously health care doesn’t only mean sickness treatment. Avoiding sickness is much better than treating it. Sadly we spend far too little energy on creating health and far too much on treating sickness.

Physical activity guidelines for adults (follow link for more details and guidelines for others) from the UK National Health Service

To stay healthy, adults aged 19-64 should try to be active daily and should do:

At least 150 minutes (2 hours and 30 minutes) of moderate-intensity aerobic activity such as cycling or fast walking every week, or
75 minutes (1 hour and 15 minutes) of vigorous-intensity aerobic activity such as running or a game of singles tennis every week
and muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders and arms).

Sedentary lifestyle can kill

one in three adults worldwide fails to do the recommended 150 minutes of moderate aerobic physical activity per week. In the UK two out of three adults don’t manage it.

So rather than stressing the health benefits of exercise, the Lancet researchers have opted to show the harm caused by inactivity. They estimate lack of exercise is responsible for about 5.3m deaths a year – about the same number as smoking.

This is based on estimates of the impact on inactivity on coronary heart disease, Type 2 diabetes, and two specfic cancers – breast and bowel – where lack of exercise is a major risk factor.

Effect of physical inactivity on major non-communicable diseases worldwide: an analysis of burden of disease and life expectancy

Worldwide, we estimate that physical inactivity causes 6% (ranging from 3Â·2% in southeast Asia to 7Â·8% in the eastern Mediterranean region) of the burden of disease from coronary heart disease, 7% (3Â·9—9Â·6) of type 2 diabetes, 10% (5Â·6—14Â·1) of breast cancer, and 10% (5Â·7—13Â·8) of colon cancer. Inactivity causes 9% (range 5Â·1—12Â·5) of premature mortality, or more than 5Â·3 million of the 57 million deaths that occurred worldwide in 2008. If inactivity were not eliminated, but decreased instead by 10% or 25%, more than 533 000 and more than 1Â·3 million deaths, respectively, could be averted every year. We estimated that elimination of physical inactivity would increase the life expectancy of the world’s population by 0Â·68 (range 0Â·41—0Â·95) years.

Scientific Illiteracy Leads to Failure to Vaccinate Which Leads to Death

Anti-vaccination propagandists help create the worst whooping cough epidemic in 70 years by Steven Salzberg is a professor at Johns Hopkins School of Medicine:

When the vaccination rates drop, everyone becomes more vulnerable to infectious diseases. When more than 90% of the population is vaccinated, we have “herd immunity” – this means the disease can’t spread because there aren’t enough susceptible people in the community. So the high rate of vaccine refusal in Washington makes it easier for whooping cough (and other diseases) to spread.
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And now we learn that the U.S. is in the midst of the worst whooping cough epidemic in 70 years. One of the most hard-hit states is Washington, which the CDC just announced (on 20 July) has suffered 2,520 cases so far this year, a 1300% increase over last year. This is the highest number of cases reported in Washington since 1942.
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The U.S. has had over 17,000 cases this year, putting it on track for the worst year since 1959. The highest rate of infection in the nation is in Wisconsin (which has also been hit hard by anti-vaccine effects), followed by Washington and Montana. 10 deaths have been reported, mostly in infants who were too young to be vaccinated. For all this, we can thank the anti-vaccination movement.

The failure of our society to appreciate the value of science has dire consequences. We are lucky to benefit from the results of scientific advances around us everyday. Some people, instead of appreciating the value of science waste these great gifts we have been given.

What people want to believe is up to them. When people’s actions risk others lives that is not ok. Drunk drivers risk others lives; therefore we don’t allow drunk driving. Society requires that people respect others right to live. It is sensible to require people to cooperate to limit damaging behavior: such as drunk driving or not being properly vaccinated.

Pertussis (whooping cough) is a highly contagious bacterial disease that causes uncontrollable, violent coughing. The coughing can make it hard to breathe. Pertussis, or whooping cough, is an upper respiratory infection caused by the Bordetella pertussis or Bordetella parapertussis bacteria. It is a serious disease that can cause permanent disability in infants, and even death.

High School Student Creates: Test That is Much More Accurate and 26,000 Times Cheaper Than Existing Pancreatic Cancer Tests

Seeing what these kids come up with is so refreshing after being so disappointed by the actions fo our leaders (politicians, business leaders, financiers, law enforcement [spying on citizens because they feel electronic privacy is fine to invade, taking away liberty…], health care in the USA [twice as expensive as elsewhere with no better results, 10 of millions without coverage]…). These kids make me feel hopeful, unfortunately the actions of the powerful leave me less hopeful.

Jack Andraka created a new paper based test for diagnosing pancreatic cancer that is 50% more accurate, 400 times more sensitive, and 26,000 times less expensive than existing methods. His method uses carbon nanotubes and can catch the disease in very early stages which is critical to treatment success. The test also covers other forms of cancer very effectively (he concentrated on the results for pancreatic cancer given the low survival rates for that cancer). Jack Andraka: “I actually love single-walled carbon nanotubes; they’re like the superheroes of material science.”

His results are great. Often initial results can be difficult to actually turn into such positive results in the real world. But this is a great step and it is great to see what young minds can do. The claims for how much better, cheaper etc. are wildly different in various places on the International Science and Engineering Fair (ISEF) site.

Jack Andraka was awarded $75,000 for his development of a new method to detect pancreatic cancer as the winner of the top prize at the Intel ISEF (I believe it is new this year to call the winner the Gordon E. Moore Award).

A Novel Paper Sensor for the Detection of Pancreatic Cancer by Jack Andraka
North County High School, Glen Burnie, MD

Continue reading →

Citizen Science: Use Your Smart Phone to Help Scientists

10 Ways You Can Use Your Smartphone to Advance Science by Matt Soniak

Scientists have started to use the abilities and prevalence of smartphones to their advantage, creating apps specifically for their studies and crowdsourcing observation and data collection. When almost everyone has an Internet connection, a camera, and a GPS unit right in their phone, almost anyone can gather, organize, and submit data to help move a study along.
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The Indicator Bats Program (iBats), a joint project of the Zoological Society of London’s Institute of Zoology and The Bat Conservation Trust, got its start with a couple of researchers working in Transylvania (of course) in 2006. The idea of the project is to identify and monitor bat populations around the world by the ultrasonic echo-location calls they use to navigate and find prey.
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The goal of Project NOAH (Networked Organisms and Habitats) is pretty ambitious: “build the go-to platform for documenting all the world’s organisms.” Their app has two modes. “Spottings” lets you take photos of plants and animals you see, categorize and describe them and then submit the data for viewing on NOAH’s website and use by researchers for population and distribution studies.
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Invasive plants and animals can crowd out natives, compete with them for food sources and alter the fire ecology of an ecosystem, disrupting its natural balance. Researchers and programmers from UCLA, the Santa Monica Mountains National Recreation Area and the University of Georgia have teamed up to create the What’s Invasive citizen science program and smartphone app. Volunteers can use the app to look up lists of the top invasive species in their area, created by National Park Service rangers and biologists. If they spot a plant or animal from the list, they submit a geo-tagged observation, with optional picture and text notes, so that scientists can locate, identify, study try to remove the species.

Great stuff.