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New Adhesive will let you climb up the wall

First there was Velcro (R), now there is Gecko!

Seriously, the wonders and joys of biomimicry are at it again.



The new adhesive is first to mimic quick catch and rapid release traits of a gecko's foot



A gecko sits atop a glass surface in this image from the NIRT laboratory. Credit and Larger Version

The National Science Foundation has released a press release all about this wonderful and potentially very useful technology. Check it out!
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Cancer and Myc

Myc is a gene that has been studied for over 20 years and is found to be overexpressed in many human cancers. The protein it codes for (which for simplicity we'll also refer to as Myc) is a transcription factor, like members of the FoxO family, which means it can enable or disable the expression of many other genes. How many? The estimate is about 15% of all human genes. Since there are at least 20,000 genes, the number regulated by Myc is 3000 or more. That's a lot of leverage.

Obviously, Myc is essential for cell function or it wouldn't have so much influence. The biological functions Myc affects include cell proliferation, cell growth, apopotosis, cell differentiation, and stem-cell self-renewal. It is possible for a single transcription factor to have such varied effects because other transcription factors (coactivators or corepressors) must also be present in order to activate or repress the expression of some specific other gene. That is, the expression of any particular gene depends on the presence (or absence) of a particular set of transcription factors.

Since Myc affects the functions mentioned above, it's hardly surprising to find that Myc is overexpressed in many cancers. In such cases, the difference between a normal cell and a cancer cell is the overexpression of Myc in the latter and possibly the abnormal presence of other coactivators or corepressors. The result in a cancer cell is excessive proliferation and/or avoidance of cell death by apoptosis.

Surely you've wondered why development of cancer therapies has taken so long. A large part of the reason is that so many genes involved in cancer interact with so many other genes that have essential functions. So it's not possible to interfere with the cancer-related genes without disrupting vital biological functions elsewhere in the body.

The expression of Myc itself is triggered by signals that are usually external to the cell and normally serve to stimulate cell growth and proliferation when needed, as in lymphocyte production, normal growth, or wound healing. Such signals are called mitogens, because they can initiate mitosis. Wnt, Shh, and EGF are mitogens that can lead to Myc expression.

It is probably almost impossible to hope to combat cancer by directly affecting Myc or its related mitogens, because all of these have essential normal functions themselves. Instead, anti-cancer research needs to examine how Myc may be overexpressed or complemented in harmful ways by other transcription factors.

One promising line of research involves cancer stem cells – cells that, like normal stem cells, can proliferate and differentiate into other cell types, and that also carry cancer-causing mutations. There is now thought to be a "signature" consisting of 11 genes that may be characteristic of cancer stem cells. One of these genes has an effect on Myc:

Scientists Uncover Role Of Cancer Stem Cell Marker: Controlling Gene Expression (1/18/08)
Scientists at Jefferson's Kimmel Cancer Center in Philadelphia have made an extraordinary advance in the understanding of the function of a gene previously shown to be part of an 11-gene "signature" that can predict which tumors will be aggressive and likely to spread. The gene, USP22, encodes an enzyme that appears to be crucial for controlling large scale changes in gene expression, one of the hallmarks of cancer cells. ...

In one example, they looked at the relationship between MYC and USP22. MYC, which is among the most commonly overexpressed genes in cancer, encodes a protein that controls the expression of thousands of other genes. The scientists showed that USP22 is a critical partner of MYC and that by depleting cells of USP22, they could prevent MYC from working properly, stopping it from inducing the invasive growth of cancer cells.


It turns out that Myc affects not only 3000 or so ordinary genes, but also a number of DNA sequences that code for microRNA – and some of these microRNAs play an important role in suppressing cancer. In fact, Myc can stop the production of at least 13 microRNAs:

Silencing Small But Mighty Cancer Inhibitors (12/12/07)
Researchers from Johns Hopkins and the University of Pennsylvania have uncovered another reason why one of the most commonly activated proteins in cancer is in fact so dangerous. As reported in Nature Genetics recently, the Myc protein can stop the production of at least 13 microRNAs, small pieces of nucleic acid that help control which genes are turned on and off.

Furthermore, additional observations showed that some of these microRNAs have an inhibiting effect on cancer, a striking result in itself:
[I]n several instances, re-introducing repressed miRNAs into Myc-containing cancer cells suppressed tumor growth in mice, raising the possibility that a sort-of gene therapy approach could be effective therapy for treating certain cancers.

Since the microRNAs repressed by Myc affect many other genes, there could be thousands of other genes indirectly affected by Myc:
"This study expands our understanding of how Myc acts as such a potent cancer-promoting protein," says Mendell. "We already knew that it can directly regulate thousands of genes. Through its repertoire of miRNAs, Myc likely influences the expression of thousands of additional genes. Activation of Myc therefore profoundly changes the program of genes that are expressed in cancer cells."

More: Researchers zero in on the tiniest members in the war on cancer (12/13/07)

Myc is actually a member of a family of genes, the Myc family. Most members of the family have similar functions. Separate members undoubtedly appeared in the course of evolution from the duplication of earlier members and later mutation. One member, called N-myc, plays a role in both normal development of the retina, as well as cancers of the retina (retinoblastoma).

Recent research has shown that N-myc seems to be responsible for the surprising fact that the retinas in all vertebrates have about the same thickness, regardless of the size of the entire animal or its eyes:

Eye Cancer Gene's Role In Retinal Development Defined (1/18/08)
"A series of complex developmental processes must be carefully orchestrated for the eye to form correctly," said Michael Dyer, Ph.D., associate member in the St. Jude Department of Developmental Neurobiology. "One important aspect of this coordination is that retinal thickness be the same, irrespective of eye size. For example, the mouse eye is about 5,000 times smaller than that of the elephant eye, but the retinal thickness in these two species is comparable."

Working with mice, the researchers found that a gene called N-myc coordinates the growth of the retina and other eye structures to ensure the retina has the proper thickness necessary to convert light from the lens into nerve impulses that the brain transforms into images.


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Science News Stories

It's a bit a bit of a smorgasborg, but here are 3 interesting links.

1. The Mississippi River is a little under the weather. Why? Way too much cabon dioxide and it's all being dumped into the Gulf of Mexico. Too much CO2 in the ocean throws off the pH and affects the living organisms there -- all of them from the microscopic plankton and algae to complex organism like coral reefs. Just like terrestial systems, too much CO2 in the air, throw off plant life and everything else in the food chain lives off the plants.

2. Understanding science, especially about your body and nutrition can help you become healthier. So this article reminds us all to mind our eating habits. Too much meat and fast food eating can have negative consequences on not only your weight, but affects heart health and diabetes risk too.

3. Finally, there's nothing like an industrious teen. Check out this article about this kid who made a fully-functional bicycle from wood. It's neat.

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Top science stories of 2007

Well, 2007 has been over for three weeks now. Must be time to look back and figure out what happened there. Overall, I'd say it was a good year, but not a great year. Let's have a look at what others picked for the "top" stories.

Science usually makes pretty good calls, as you'd expect. Since online access is by subscription only, here's my paraphrase of their list of top "breakthroughs":

  1. Recognizing human genetic variation – in other words, there's more diversity in human DNA than expected
  2. Making pluripotent stem cells by reprogramming
  3. Closing in on the origins of ultra-high-energy cosmic rays
  4. Determining the structure of a G protein-coupled receptor (for adrenaline)
  5. Investigating transition metal oxides as an alternative to silicon for electronics
  6. Exploring the prospects of materials exhibiting the quantum spin Hall effect for realization of spintronics
  7. Understanding how asymmetric division occurs in CD4 T cells
  8. Growing ability to synthesize complex pharmaceutical and electronic compounds
  9. Adding to the evidence that memory is an important ability for imagining future events and situations
  10. Proving that it is possible (for a computer) to never lose a game of checkers against a human (or another computer)

There are some surprising developments in this list – such as the extent of human genetic diversity or (especially) the apparent ease with which cells can be reprogrammed to behave like pluripotent stem cells. But what strikes me most about the list is that not much in it gives a sense of "closure" in the way that, say, determining the genetic code or proving the Poincaré conjecture (last year's top "breakthrough") was.

Instead, what we have are a number of developments that are merely the first steps towards much more impressive things to follow. We are just beginning to understand how genetic programs actually work, especially in disease conditions and in processes like metabolism and cell division. There will be much more meaningful developments with stem cells, protein structure determination, molecular synthesis, non-silicon electronics, spintronics, and nanoscale engineering.

I suppose this is why the items in the list are called "breakthroughs".

Here's a press release from the AAAS with a synopsis of their list: Human genetic variation -- Science's 'Breakthrough of the Year' (Physorg.com)

Many other lists of top stories could be found. Here are some of them, with my somewhat jaundiced opinion of most, as well as a bit of measured praise for the less awful.


2007: A year of stunning progress in the science of life (Guardian Unlimited)
Please read this one. It's not particularly lengthy, and it will be instructive to compare it with most of the other articles summarized below. It's lucid, and not larded with fluff.

In terms of what's actually noted as key advances, it covers genetics, synthetic biology, stem cells, cloning, and regenerative medicine. And despite the title, it also covers climate change and further improved evidence of dark matter.

Year in science review: Global warming, new species (USA Today)
The quality of this list is surprisingly good, considering the source. (Scientific American should be ashamed – fat chance.) Significant items include climate change (a perennial winner), stem cells, the extremely bright supernova SN 2006gy, and the Earthlike planet of Gliese 581. As a sop to the mass-market audience for "science" the list also includes dinosaurs, vanishing honeybees, and the discovery of many new biological species, alongside the looming extinction of others.

2007 News review (NewScientist)
The main list is sparingly presented in a few brief paragraphs. The selections are a bit odd (the dangers of noise pollution? really?). But in a sidebar there's a tidy list of links to separate additional articles, allowing you to easily avoid whatever you might regard as needless tedium. What I don't quite understand is the removal of, oh maybe 75% of science, to a separate article on 2007: The year in biology and medicine.

Top 25 Science Stories of 2007 (Scientific American)
Much of this list is in the nature of tabloid-style science "journalism" – all too pathetic a reminder of what is far too widely considered to be "newsworthy" in the realm of science. Not quite as bad as the printed birdcage liner found at a supermarket checkout station, but close. Daylight saving time redefined? Some guy with TB goes on a honeymoon to Europe? Poisoned pet food? Baseball jocks on steroids? Oh, please. They forgot to mention flying saucer or Yeti sightings – surely there must have been some.

See, the problem with this is that it tends to trivialize, by association, those few stories they included which were actually important, such as climate change, stem cells (the science, not the bogus controversy), and Earthlike extrasolar planets.

Top 10 Scientific Discoveries (Time)
Fortunately, this list is shorter than Scientific American's, so there's less tabloid-style dreck in it. And what there is of that isn't quite so egregious (dinosaurs, "kryptonite", an elderly clam). This makes for a somewhat higher percentage of actual science (stem cells, human genome, supernova SN 2006gy, extrasolar planets).

But here's the depressing thing about this list. Not so much the content, which doesn't quite treat the readership as unqualified imbeciles, but rather the presentation, which treats the readership as short-attention span consumer droids who will docilely plow through separate pages for each story, replete with stock photo imagery, brief text, and delightful time-wasting banner ads and "sponsored links".


Briefly noted: Here are some more specialized or other "best of 2007" lists that don't seem to require much further comment from me. Some are good; others are..., well, just other.

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Sirtuin news

Back in November we had a series of posts about sirtuin proteins. This included an overview, with a particular focus on the relevance to calorie restriction and longevity, especially in light of recent research announcements at the time. This was followed by a couple of posts (here, here) on background history.

Now is a good time to return to that thread and continue the discussion of sirtuins, because of additional related research announcements, including especially this:

Sirtris Announces Positive Results with Proprietary Version of Resveratrol, SRT501, in a Phase 1b Type 2 Diabetes Clinical Study (1/7/08)
Sirtris Pharmaceuticals, Inc. ... announced today that the Company's first product to enter the clinic, SRT501, was found to be safe and well-tolerated, and was found to significantly lower glucose in an oral glucose tolerance test conducted as part of a 28 day Phase 1b clinical study in patients with Type 2 Diabetes.

This 28-day Phase 1b study was designed to assess the safety, tolerability and pharmacokinetics of once-daily, orally administered doses of either 2.5 g or 5 g of SRT501 in patients with Type 2 Diabetes who were naive to other diabetes drug treatments. Both doses of SRT501 were found to be safe and well-tolerated, and pharmacokinetics, a measure of drug levels in the blood, were identical at days one and 28, suggesting no drug accumulation. There were no serious adverse events and no dose-related adverse events. Importantly, SRT501 showed a statistically significant improvement in an oral glucose tolerance test on day 28 at two hours and a trend towards lower fasting plasma glucose levels.

SRT501 is also being tested in patients with Type 2 Diabetes in a Phase 1b BID (twice daily administration) study and in a Phase 2a study in combination with metformin, the current first-line therapy for Type 2 Diabetes. SIRT1 is the founding member of the human sirtuin family of enzymes which control the aging process. Specifically, SRT501 acts by increasing mitochondrial activity and therefore is targeted to address metabolic diseases, such as Type 2 Diabetes.

"This is the first time that a small molecule targeting sirtuins, the genes which control the aging process, has shown efficacy in a disease of aging," said Peter Elliott, Ph.D., Senior Vice President of Development at Sirtris.

OK, this is obviously a self-promotional PR piece from the drug developer. In particular, sirtuins aren't "the genes which control the aging process", merely some of them. However, if the claims hold up under further testing, especially the one stated in the last paragraph, this is an important validation of much prior research into the effect of sirtuins on longevity as a result of action in various cellular pathways. Our previous discussions reviewed some of this research conducted on model organisms like yeast and the nematode C. elegans.

More information: Resveratrol-like drug works in humans-Sirtris (1/7/08), Sirtris Anti-Aging Drug Generates Buzz, But May Already Be Old News (1/8/08)

This drug, SRT501, has been in human clinical trials for about a year and a half already. The initial trial (called "Phase 1") involved 85 healthy volunteers and began in June 2006 (see here). Results from that trial were reported in October 2006 (see here) and demonstrated that the drug was reasonably safe and well-tolerated.

SRT501 is a small molecule drug that achieves its effects by activating the mammalian SIRT1 NAD-dependent deacetylase enzyme, which has been investigated extensively for a decade (as discussed here). The drug is essentially just a proprietary formulation of resveratrol, the well-known component of red wine that has been shown to have lifespan-extending and anti-diabetes properties in several model organisms. (See here for an extended discussion, including reports of important research announced in late 2006.) SRT501, however, is a much more practical way to take advantage of resveratrol, compared to consumption of red wine, where hundreds or thousands of bottles of wine would be needed to achieve the same effect.

Perhaps the most important result shown by this newly reported result is that SRT501 actually seems to provide measurable beneficial effects of improved glucose tolerance and reduced blood glucose levels for humans with diabetes.

SIRT1 activators which are apparently much more powerful than SRT501 are under active investigation at Sirtris and in the laboratory of Sirtris co-founder David Sinclair. This has been documented in research that was published last November:

Sirtris unveils promising, novel SIRT1 activators for treating diseases of aging (11/28/07)
In November 2006, Sirtris scientists and Sirtris co-founder, Prof. David Sinclair from Harvard Medical School, published consecutive papers in the journals Cell and Nature showing that resveratrol, a SIRT1 activator found in red wine, could reduce the impact of a high fat diet, increase stamina two fold and significantly extend lifespan of mice. Unfortunately, it was estimated that a person would need to drink 1000 bottles of red wine to obtain an equivalent dose of resveratrol. Now, scientists at Sirtris have developed SIRT1 activating molecules that are chemically distinct from resveratrol and are 1000 times more potent.

"The new drug candidates represent a significant milestone because they are the first molecules that have been designed to act on genes that control the aging process. For this reason, we feel they have considerable potential to treat diseases of aging such as Type 2 Diabetes," said Christoph Westphal, M.D., Ph.D., Chief Executive Officer and Vice Chair of Sirtris Pharmaceuticals. "The breakthrough in potency we have achieved with the novel chemical entities (NCEs) means that we can obtain the health benefits of resveratrol with a considerably lower dose."

Here's a useful professional assessment of these results: Sirtuin activators as anti-diabetes drugs, and beyond (11/29/07) More: Sirtris Drug May Slow Aging, Create 'Armstrong' Cells (11/28/07)

Additional information:

Gene Believed To Promote Long Life Linked To Cholesterol Flushing (10/12/07)
Research conducted in part by sirtuin-research pioneer Leonard Guarente has established one mechanism through which SIRT1 provides health and longevity benefits. The mechanism promotes flushing harmful buildups of cholesterol in macrophage cells of the immune systems of mice. This mechanism could explain part of the health benefits of SIRT1-activators such as resveratrol and calorie restriction.

Red Wine Ingredient -- Resveratrol -- Fights Diabetes In Mice (10/4/07)
Chinese researchers have reported that relatively low doses of resveratrol can improve insulin sensitivity in mouse cells, and they believe this effect is due to SIRT1 activation by resveratrol. Additionally, the researchers found that SIRT1 levels are reduced in insulin-resistant cells, and that increased SIRT1 activity improved insulin sensitivity

Sirtris Pharmaceuticals – Treating Disease by Modulating Sirtuins
This is a brief overview of Sirtris Pharmaceuticals drug development focus.


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School of Business confirms recipe for herd behavior

Popular opinion not always so popular
Whether you're a voter choosing the next president, a manager making policy decisions or a consumer selecting a brand, it's likely your decision is influenced by the opinions of others.

But beware: Your estimate may well be based on a lone, repetitive voice that you've mistaken for a chorus, say researchers at the University of Michigan's Ross School of Business.

Professors Stephen Garcia and Norbert Schwarz say that much like the squeaky wheel that gets the grease, a single opinion repeated often enough has nearly as much influence as one expressed by several people.

"What we think others think greatly influences our own personal thoughts, feelings and behavior," said Garcia, adjunct assistant professor of management and organizations at the Ross School. "Quite obviously, an opinion is likely to be more widely shared the more different people express it. But surprisingly, hearing one person express an opinion repeatedly also leads to the conclusion that the opinion is more widespread relative to hearing the same opinion expressed only once."


Is there any doubt about the reasons this sort of thing is studied and taught in "business schools"?
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Supernova Remnants Dance in the LMC

Supernova Remnants Dance in the LMC

The Gemini South Multi-Object Spectograph (GMOS) recently captured a dramatic image of a vast cloud complex named DEM L316 located in the Large Magellanic Cloud. The peanut-shaped nebula appears to be a single object, but the latest research indicates that it is really comprised of two distinct gas and dust clouds formed by different types of supernova explosions.

The new image reveals the intricate tendrils of gas and dust located in the remnants of the stellar explosions that created the still-expanding cloud complex. The object was first recognized in the early 1970s as a supernova remnant, a type of object that is enriched with elements created in stellar explosions. The nebula was likely created a few tens of thousands of years ago by more than one type of supernova exploding in this region of the Large Magellanic Cloud.




DEM L316 – click for 1000×1000 image


Additional information: here
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Interactive Science Lesson - Cancer

Okay, it's not urban ecology, but it is an important matter -- your health. Cancer is a comm0n disease that affects every living creature (yes, any kind of animal or plant can get cancer) and every tissue (any part of your body can get cancer). Not all cancers are fatal, but it can really bring you down. One important thing to understand about cancer is that it is based on a completely natural biological process - Mitosis. Any student who has taken high school biology or higher has heard it. Quick and dirty: Mitosis is the way a cell divides & reproduces. It's how we get new skin cells and other tissue cells to keep our bodies going. But with cancer, the cells don't stop reproducing and things just get all our of hand.

Children's Hospital Boston has a great interactive website about how cancer grows and spreads.
It's a perfect way to introduce a science lesson about cancer or supplement a mitosis or disease physiology lesson.
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Teens, Sex, and Technology

My intended audience for this site are teens and families. Though the main purpose is to share urban ecology and urban wildlife science, I sometimes feel compelled to share information I think would be generally useful for young people. I post about human behavior sometimes, usually in the context of 'what we can do to have a lesser impact on nature'. But I also care about young people being safe and ready for adulthood. I have worked with and mentored many young people (middle school and high school age) and I am very concerned about their perception of sex and the quality of sex education they receive. I know too many teen girls and boys who are parents and/or who have had to treat a STI.

It is for this reason that I am sharing the following links with you all. Please visit them and share with others, especially the young people in your lives.

Fresh Focus Video Contest: Why Is Sex So Interesting and Sex Ed So Boring?
There are 10 Sex Ed Video Contest short films. These shorts were produced by young people. They film their Sex ed experiences and how inadequate the lessons were and what they wished their parents, teachers, and other adults had taught them about sex. Great conversation starters and sex education tools for young people. Check out their videos and vote for your favorites. You have until January 16th to vote. Winners will be announced January 22nd. I'm partial to Video 9 I must admit. My cousin, a film school student and new intern for Spike Lee, produced it and her younger sister is the main character in the . I am so proud and I am shamelessly asking you to vote for it. But many of the others are great, too.

Sex::Tech Conference Focus on Youth
This organization seems to be a great online resource with real talk answers about sex and technology aimed at young people. They are even sponsoring a conference on STD/HIV Prevention for Teens in San Francisco.

Stay informed. Stay Safe. Let's all work together to help young people become healthy adults.
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Cool New Science Discoveries

Discovery #1: Photosynthesis...not just for plants and algae anymore.
Well, something like that. A new discovery has found that a species of clam can actually gulp air and covert it to protein. Yes, using microbes that live in its gut, the clam can covert the Nitrogen in the air and make protein. Proteins are to animals what carbohydrates are the plants -- the main building blocks for tissue growth. Plant tissues are mostly made of carbon and Animal tissues are mostly made of Nitrogen. For both plants and the shipworm, they can take inert, non-active carbon and nitrogen in the air and create building blocks. Check out the full story.

Discovery #2: Skating on thin, short-lived ice.
Particularly in the northern US and Canada, ice skating on the river and lakes are apart of local traditions. But with recent concern over climate change, a team of scientists looked into records of lake and river freezes over the lst 150 years. The deep freeze season is getting shorter. Lakes and rivers are freezing later and the thaw comes sooner each year. This means a short ice skating season. Plus, there is a record of air temperatures increasing a little more than 1 degree Celsius over the last 100 year. I know it doesn't seem like much, but it adds up. Check out the full story.
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Book Review: Little Lost Bat

Each year the Animal Behavior Society selects an Outstanding Children's Book that accurately presents animal behavior and behavior ecology in literature for children in grades 3-5.
The following title was one of the finalist for the 2007 Award. This book was my personal favorite. I even cried at the end.

Animal Behavior for Kids: Children’s Book Award Book Review

Title: Little Lost Bat
Author: Sandra Markle
Illustrated by Alan Marks
Published by Charlesbridge, Watertown, MA

The author and illustrator create a touching and accurate image of the birth and care of an infant Mexican free-tailed bat. The story depicts realistic accounts of the ups and downs of the life of a young bat – the struggle to stay warm, clinging to the safety of the cave ceiling, and the daily ritual of locating its mother by call among the other thousands of bat calls. The students were most impressed with the description of the birth of the baby bat, noting how the mother curls her body into a hammock shape while hanging upside-down. Students were able to relate the care and attention the mother bat provided her baby to the care and attention their own mothers provide to them and their siblings. The story also tells of loss and survival and how caring and affection exist among all animals, not just humans. I, like many of the students, would recommend this book to friends.
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Urban Wildlife Watch - Earthworms

During hot summer days, my younger sibling often tryies to rescue poor little earthworms trying to cross the hot sidewalk. It's as if the little guys started out early that morning, when the day was fresh and cool and still moist with dew at the edge of the walk. They were inching their way ever so steadfast across the walk. Creep. creep. creep.
And then, the sun began to rise higher in the sky, and the dew evaporated. The side walk warmed. A few passer-bys squished a worm here. there. A robin snagged a few plumped snacks.
The sun is high in the sky. And the poor worm is getting ever so dry and parched. And by 2 pm, the hottest part of the day, the little guy is dry. Withered away and stuck to piping hot concrete. Only inches away from the soil on the other side of the walk.

Poor little worms, my sibling would remark. But, you may also notice more earthworms when you're doing yard work, tilling soil, planting grass or trees or shrubs. Their thick, juicy, moist bodies peak through the soil here and there. You may have also noticed more earthworms following a rain shower. LiveScience.com has posted this great little reader about why
Earthworms come out when it rains.

Enjoy looking out for Earthworms -- the oft overlooked urban wildlife.
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Physical sciences news, 12/24/07 - 12/30/07


High-energy galactic objects
Objects in our galaxy that are capable of generating hard X-rays or the even higher-energy gamma-rays are quite unusual, and therefore of significant scientific interest. A European ground-based observatory known as H. E. S. S. (High Energy Stereoscopic System) is capable of indirectly detecting TeV gamma-rays. One of the sources it has found, designated as HESS J1837-069, has also been detected by the Japanese Suzaku satellite X-ray observatory, and is suspected to be what is called a "pulsar wind nebula". A similar object, HESS J1614-518, which is the brightest extended TeV gamma-ray source discovered in the H. E. S. S. galactic plane survey, has also been observed as a weak X-ray source by Suzaku.

Mysterious Cosmic Powerhouses Explored
Discovery of Extended X-Ray emission from the unidentified TeV source HESS J1614-518 using the Suzaku Satellite
The INTEGRAL - HESS/MAGIC connection: a new class of cosmic high energy accelerators from keV to TeV

X-rays from rotating radio transients
Compact objects first known only by periodic short bursts of radio-frequency photons have been suspected to be rotating neutron stars and are called "rotating radio transients". Periodic X-ray bursts occurring much more frequently from one such object (J1819-1458) have been detected by the XMM-Newton satellite X-ray observatory, and they support the identification of the object as a neutron star.

XMM-Newton Detects Pulsed Heartbeat Of A Weird New Type Of Star
Pulsed Heartbeat Star
Discovery of Pulsations and a Possible Spectral Feature in the X-ray Emission from Rotating Radio Transient J1819-1458

Star formation
Yet another illustration of the value of observing astronomical objects in diverse portions of the spectrum comes from studies of a protostar known as HH-211. Radio-frequency observations show jets of matter emerging from the poles of the rotating protostar, while infrared observations show emissions from shocked molecular hydrogen in a region of gas surrounding the jets. The observations support the hypothesis that the jets carry off angular momentum, allowing gradual growth of the protostar.

Jets Are a Real Drag
Jets Spiral in 'Reverse Whirlpool' from Star
Submillimeter arcsecond-resolution mapping of the highly collimated protostellar jet HH 211

Extrasolar planets
The existence of most extrasolar planets detected so far has been deduced indirectly from perturbations in the movement of its parent star. But extrasolar planet HD 189733b has proven to be one of the most amenable extrasolar planets to direct observation. (For example, here.) Now it has actually been observed by reflected light from the stellar parent.

Polarization technique focuses limelight
Studying Planets With Sunglasses
First Reflected Light from an Exoplanet?

Nanoparticle medicine
In the last year or so there has been quite a flood of reports of the use of nanoparticles as medical diagnostic tools or mechanisms for combating cancer and infectious diseases by heating or delivery of drugs. The past week has brought two more examples, involving gold nanoparticles. In one example the nanoparticles bind specifically to tumor cells, where they can be observed using laser illumination. In a second example the nanoparticles bind to the parasite responsible for toxoplasmosis. The parasite is destroyed when the nanoparticles are heated using suitable illumination from a laser.

Gold Nanoparticle Probes May Allow Earlier Cancer Detection
'Golden Bullet' Shows Promise For Killing Common Parasite
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Science.TV

Guess what I just learned about...ScienceTV, an online video-sharing website for people interested in science. It was just recently launched, but it includes channels and categories of science topics and target groups.
It's been a while since I've thougt again about creating a show, but this seems like such a great time to get back in the saddle.

I'll start getting my stuff together.
Wish me luck and I look forward to sharing my Urban Science Adventures with you.
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Economics 101

I'm going to broaden the focus here with a lesson in elementary economics. This is a fairly standard example used by economists everywhere, to illustrate how competitors position themselves to divide up a market.

Suppose there is a nice beach somewhere. (It may be either swimsuit optional, or else the gov't requires all users to wear suits, because the gov't knows what's best for everyone. However, that's not germane to what follows.)

Suppose further that two hot dog vendors want to locate their carts on the beach in order to maximize their revenue. You might think that the best way to do this is to imagine the beach divided in half, with each vendor in the middle of one half. That places one 1/4 of the way from one end, and the other 1/4 of the way from the other end. Assuming people are uniformly distributed on the beach, this minimizes the maximum distance a customer needs to walk in order to get a hot dog – at most 1/4 the length of the beach.

But counterintuitively, either vendor can apparently do better by moving to the middle of the beach. That way the vendor who moves to the middle first can still have all of his previous customers, plus half the customers between the center of the beach and the other vendor. Unfortunately, if the other vendor moves to the center also, to avoid losing business, the total quantity of hot dogs sold will be less for both than previously. This is because about half of the customers would have to walk farther to get a sausage, and many of these won't want to get so much exercise.

Actually, however, this only illustrates how hypothetical a lot of reasoning by economists is. What "should" happen if markets were efficient (which they aren't) is that after both existing vendors have moved to the center, then somebody with a little capital would buy new carts, hire two undocumented immigrants (at less than minimum wages), and set them up in the old .25/.75 points.

This could go on indefinitely, until the "point of diminishing returns" when the market for hot dogs on the beach is "saturated".

But at that point, someone with even more capital would step in with an advertising campaign to promote eating hot dogs to beach-goers, and then set up additional carts, selling hot dogs made from recycled turkey parts at prices below cost, to drive all the other vendors out of business. Then the last entrant can buy up the remaining assets in bankruptcy, cut back on the number of locations, but not raise the product quality, and make more money than everyone in total previously.

Maybe, just maybe, the beach-goers would demand gov't regulation of hot dog vendors at that point. But the remaining vendor can use his substantial profits to buy off any relevant gov't officials and fix any elections that might be held (using his electronic voting machine subsidiary), to prevent any gov't action.

And then, using this new gov't-relations infrastructure, the vendor would lobby for gov't subsidies to help produce lower-cost hot dogs. The gov't would oblige (since many officials are former vendor executives) and hold secret meetings to plan the subsidies and make all necessary arrangements. Mainstream media (large portions of which are owned by friends and suppliers of the vendor) would laud the gov't for its foresight. Some sharp lawyers might challenge such practices in court, but since a majority of judges have been appointed by the gov't on the advice of its lobbyists, the lawsuits would go nowhere. Further lawsuits would be forestalled by "tort reform".

And "consumers" would go on obliviously, happily eating hot dogs until they (the "consumers") keel over from cardiovascular disease, due to bad diet and lack of exercise. The only mistake made by the vendor and his allies in all this is failing to secure gov't health care to keep the "consumers" alive a little longer. Because "economists" had forecast that such a move would not actually improve profits in the long run, since older "consumers" would be too sick to eat many hot dogs.

Wealthy preachers of religion would then step in to assure the populace that all of this was God's plan, and remind all the survivors that there was still time to contribute to the church's building fund, before the Rapture.

Happy New Year!

Update (1/12/08): At a link to this post, the writer comments that governments and other powerful actors have long intervened in economic affairs. The example cited involves medieval cartels and monopolies, but of course this goes back much farther in history – as long as any sort of gov't has existed, I would suppose.

And in case anyone thinks this note is a little over the top in parodying economics, here's something I came across just a few days after writing the above. It's by economist and hedge fund manager Jean Paul Schmetz:
In my field (theoretical economics), I believe that most ideas taught in economics 101 will be proved false eventually. Most of them would already have been officially defined as false in any other more hard-science, but, because of lack of better hypotheses they are still widely accepted and used in economics and general commentary. Eventually, someone will come up with another type of hypotheses explaining (and predicting) the economic reality in a way that will render most existing economics beliefs false.
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