Category Archives: Life Science

The Avocado

I bought an avocado a the supermarket yesterday. While eating some today I decided to search the internet for some nutritional information. That info wasn’t that interesting to me, but I did find this interesting: the avocado fruit does not ripen on the tree. When it is harvested it will ripen. If the fruit is picked once it reaches maturity, and will then ripen in a few days. This can be speed up by putting the avocado in a paper bag and speed up more if other fruit such as bananas are included, because of the influence of ethylene gas.

Feeding avocados to any non-human animal should be avoided completely. There is documented evidence that animals such as cattle, horses, goats, rabbits, birds, dogs, cats, and even fish can be severely harmed or even killed when they consume the leaves, bark, or fruit. Avocados contain a toxic fatty acid derivative known as persin. Many animal organizations recommend total avoidance of all parts of the plant.

Anyway I found the information interesting 🙂 Related: Bannanas Going Going Gone – Eat food. Not too much. Mostly plants. – Drinking Soda and Obesity

Patenting Life – a Bad Idea

Patenting Life by Michael Crichton (new book = Next, also The Andromeda Strain, Jurassic Park…):

Gene patents are now used to halt research, prevent medical testing and keep vital information from you and your doctor. Gene patents slow the pace of medical advance on deadly diseases. And they raise costs exorbitantly: a test for breast cancer that could be done for $1,000 now costs $3,000.

Why? Because the holder of the gene patent can charge whatever he wants, and does. Couldn’t somebody make a cheaper test? Sure, but the patent holder blocks any competitor’s test. He owns the gene. Nobody else can test for it. In fact, you can’t even donate your own breast cancer gene to another scientist without permission. The gene may exist in your body, but it’s now private property.

This bizarre situation has come to pass because of a mistake by an underfinanced and understaffed government agency. The United States Patent Office misinterpreted previous Supreme Court rulings and some years ago began — to the surprise of everyone, including scientists decoding the genome — to issue patents on genes.

This has to be fixed, and here is one way that might help: Continue reading →

Skin Bacteria

Close Look at Human Arm Finds Host of Microbes:

“The skin is home to a virtual zoo,” said Blaser, a microbiologist who last week published online the first molecular analysis of the bacteria living on one small patch of human skin. “We’re just beginning to explore it.” The analysis revealed that human skin is populated by a diverse assortment of bacteria, including many previously unknown species, offering the first detailed peek at this potentially crucial ecosystem.

The work is part of a broader effort by a small coterie of scientists to better understand the microbial world that populates the human body. Virtually every orifice and the digestive tract are swarming with bacteria, fungi and other microbes. By some estimates, only one out of every 10 cells in the body is human.
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Blaser’s team swabbed an area of skin about the size of silver dollar on the right and left forearms of three healthy men and three healthy women. They then used sophisticated molecular techniques to amplify and analyze fragments of bacterial DNA captured by the swabs. The analysis revealed 182 species, the researchers reported. Of those, 30 had never been seen. They identified an additional 65 species when they sampled four of the volunteers eight to 10 months later, including 14 new species.

Continue reading →

DNA Transcription Webcast

DNA Transcription webcast – via How DNA transcription works

Produced by The World Wide Web Instructional Committee (WWWIC) at North Dakota State University faculty dedicated to developing internet-based educational software. Funded by NSF and the US Department of Education.

Mini Helicopter Masters Insect Navigation Trick

Mini helicopter masters insect navigation trick:

A miniature robotic helicopter has revealed a simple yet effective visual trick that lets insects fly so adeptly without sophisticated avionics.
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As insects fly forwards the ground beneath them sweeps backwards through their field of view. This “optical flow” is thought to provide crucial cues about speed and height. For example, the higher an insect’s altitude, the slower the optical flow; the faster it flies, the faster the optical flow.

Previous experiments involving bees suggest that optical flow is crucial to landing. Maintaining a constant optical flow while descending should provide a constant height-to-groundspeed ratio, which makes a bee slowdown as it approaches the ground. Distorting this optical flow can cause them to crash land instead.

Mystery Ailment Strikes Honeybees

A mysterious illness is killing tens of thousands of honeybee colonies across the country, threatening honey production, the livelihood of beekeepers and possibly crops that need bees for pollination. Researchers are scrambling to find the cause of the ailment, called Colony Collapse Disorder.
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The country’s bee population had already been shocked in recent years by a tiny, parasitic bug called the varroa mite, which has destroyed more than half of some beekeepers’ hives and devastated most wild honeybee populations.

Along with being producers of honey, commercial bee colonies are important to agriculture as pollinators, along with some birds, bats and other insects. A recent report by the National Research Council noted that in order to bear fruit, three-quarters of all flowering plants _ including most food crops and some that provide fiber, drugs and fuel _ rely on pollinators for fertilization.

No Sleep, No New Brain Cells

No sleep means no new brain cells

The researchers compared animals who were deprived of sleep for 72 hours with others who were not. They found those who missed out on rest had higher levels of the stress hormone corticosterone. It would be interesting to see if partial sleep deprivation – getting a little bit less sleep every night that you need – had the same effect

They also produced significantly fewer new brain cells in a particular region of the hippocampus. When the animals’ corticosterone levels were kept at a constant level, the reduction in cell proliferation was abolished. The results suggest that elevated stress hormone levels resulting from sleep deprivation could explain the reduction in cell production in the adult brain.

Sleep patterns were restored to normal within a week. However levels of nerve cell production (neurogenesis) were not restored for two weeks, and the brain appears to boost its efforts in order to counteract the shortage.

‘Hobbit’ human is a new species

‘Hobbit’ human ‘is a new species’:

Archaeologists had found sophisticated tools and evidence of a fire near the remains of the 1m-tall adult female. “People refused to believe that someone with that small of a brain could make the tools,” said Professor Falk. She said the Hobbit brain was nothing like that of a microcephalic and was advanced in a way that is different from living humans.

A previous study of LB1’s endocast revealed that large parts of the frontal lobe and other anatomical features were consistent with higher cognitive processes. “LB1 has a highly evolved brain,” said Professor Falk. “It didn’t get bigger, it got rewired and reorganised, and that’s very interesting.”

RNA interference webcast

If you are like me, it might take awhile to understand all that is said, it is packed with information.

via: Video of RNAi in action

How The Brain Rewires Itself

How The Brain Rewires Itself:

The finding was in line with a growing number of discoveries at the time showing that greater use of a particular muscle causes the brain to devote more cortical real estate to it. But Pascual-Leone did not stop there. He extended the experiment by having another group of volunteers merely think about practicing the piano exercise. They played the simple piece of music in their head, holding their hands still while imagining how they would move their fingers. Then they too sat beneath the TMS coil.

When the scientists compared the TMS data on the two groups–those who actually tickled the ivories and those who only imagined doing so–they glimpsed a revolutionary idea about the brain: the ability of mere thought to alter the physical structure and function of our gray matter.