4th Grade Science: March 2013

Sunday, 31 March 2013

Perimeter Information Reduce Brand new Light about Renaissance Body Masterpiece

When the Renaissance physician and expert dissector Andreas Vesalius first published "De humani corporis fabrica" in 1543, he provided the most detailed look inside the human body of his time.

A previously unknown copy of the impressive anatomy textbook resurfaced a few years ago, and it apparently contains more than a thousand hand-written notes and corrections by the author himself. The annotations reveal that Vesalius was meticulously planning a third edition of the book that never made it to print, researchers say.

"This book is his work bench as much as the dissecting table," Vivian Nutton, a University College London professor emeritus, writes in a recently published analysis of the text in the journal Medical History.

Some edits show that Vesalius wanted to correct mistakes of grammar and syntax and to make his Latin more elegant. Other markings show that he wanted to draw attention to misshapen or illegible letters for his block-cutter. Vesalius also intended to add new information to the text as he learned more about the human body, including what may be one of the oldest references to the practice of female genital mutilation.

In his discussion of circumcision, Vesalius scrawled at the bottom of the page that Ethiopians "cut off the fleshy processes from new born girls in accordance with their religion in the same way as they remove the foreskins of boys, 'although in their religious ceremonies they are otherwise generally similar to those of us Christians,'" Nutton writes. "This is arguably the first reference in a medical text to female genital mutilation for non-medical purposes."

The copy of the book, on loan from an unnamed German collector, is currently available for study at the University of Toronto's Thomas Fisher Rare Book Library.

"He is seen constantly attempting to improve his text both scientifically, and stylistically, and to make it clearer and more accessible to his readers," Philip Oldfield, science and medicine librarian at the University of Toronto, said in a statement this week. "All the evidence points to the conclusion that Vesalius was preparing a new edition of De fabrica that unfortunately never materialized."

The book will be featured as part of an exhibition next year in Toronto to mark the 500th anniversary of Vesalius's birth.

How ancient life could possibly have return concerning

Loved ones tree unites a diverse group of people that each one carry genetic vestiges issued from a only common ancestor along at the base of one's tree. however this organizational structure falls apart if genetic data could be a communal resource as opposed to actually loved ones possession.

Some evidence suggests that early evolution may have been based on a collective sharing of genes. A group of researchers are now searching for clear genetic vestiges from this communal ancestry.

But it's hard to shake our fascination with family trees.

My father used to travel for work, and when he arrived in a new city, he'd open up the phone book and check for anyone listed with our uncommon last name. Occasionally he'd get a hit and brazenly call them up to ask: "Are we related?"

The answer was always yes, with the common link often being my great grandfather.

Like my father, biologists are curious about family ties, but they go about it in a more systematic way. Rather than phone books, they sift through genetic codes from humans to bacteria and a lot in between. The main question is: Are the commonly held genes similar enough to point to a common origin?

The answer has always been yes. The implication is that we all belong to some universal tree of life. And at the base of this tree — some have imagined — there sits a mild-mannered microbe that lived more than 3 billion years ago, unaware that its genes would be the starting point of an entire planet's worth of highly differentiated life.

However, this organism, the so-called last universal common ancestor (or LUCA), may be just a fantasy.

"Our perspective is that life emerged from a collective state, and so it is not at all obvious that there is one single organism which was ancestral," said Nigel Goldenfeld from the University of Illinois at Urbana-Champaign.

The organisms belonging to this collective state would have shared genetic information from neighbor to neighbor, rather than solely from parent to offspring. Goldenfeld is leading a new NASA Astrobiology Institute (NAI) team that aims to provide a clearer understanding of this early stage of evolution.

"We are hoping to find fossils of the collective state in the genomes of organisms," Goldenfeld said.

Goldenfeld's team will be performing genetic studies that will try to tease out signatures of community-based evolution. They will complement this field and laboratory work with theoretical modeling and computer simulations.

"The ultimate goal is to understand how our planet's biochemistry is an instantiation of the universal laws of life, thus addressing the question of whether life is an inevitable and thus widespread outcome of the laws of physics," Goldenfeld said.

A time before Darwinism

It might sound strange that an organism's genetic code could be the result of "crowdsourcing." We are more familiar with traditional reproduction, as practiced by the birds and the bees.

In so-called "vertical gene transfer," an organism inherits its genome from its parents, but it does not receive an exact copy. Small changes enter the code through reproductive mixing and mutations. This "descent with modification," as Darwin put it, eventually allows a population of interbreeding organisms (or species) to evolve.

If every snippet of DNA was solely the product of descent with modification, then every organism could be placed on a tree of life stemming from a single ancestor. But as it turns out, "different genes go back to different ancestors," said Peter Gogarten of the University of Connecticut, who has done extensive work on comparative genetics.

How is that possible? It can happen if organisms share genes. Imagine a gene belonging to members of a specific family tree. One day, this gene becomes isolated and gets picked up by another organism with a different family tree. No reproduction between partners takes place — only an "adoption" of a specific gene.

This so-called "horizontal gene transfer" is quite common among bacteria and archaea, as exemplified by antibiotic resistance. When a specific bacterium develops a defense against some drug, the corresponding gene can pass horizontally to others in the same colony.

A 2008 study in the journal Proceedings of the National Academy of Sciences (PNAS) found that 80 percent of the genes in bacteria were horizontally transferred at some point in the past.

Complex organisms also exhibit evidence of horizontal (or lateral) gene transfer, albeit to a lesser extent. Researchers have shown that ancient ancestors of plants and animals "swallowed up" other bacteria to form symbiotic relationships, which eventually resulted in specialized cellular components, such as mitochondria and chloroplasts.

In his work, Gogarten has shown that horizontal gene transfer turns the tree of life into a thick bush of branches that interweave with each other. Many of these branches terminated long ago due to extinction, but some of their genes live on in us, thanks to horizontal gene transfer.

Several studies suggest that horizontal gene transfer was more prevalent in the past when nothing but single-celled organisms inhabited the Earth.

"I like to think of early life as being more like an undifferentiated slime mold," Goldenfeld said. "Such a communal form of life would have no meaningful family tree, because it is the community that varies in descent, not individual organismal lineages."

Evolving evolution

The late Carl Woese, a colleague of Goldenfeld, was one of the first scientists to propose that early life leaned heavily on horizontal gene transfer. Woese passed away in December of last year. He is perhaps best-remembered for classifying life into the now-well-accepted domains of bacteria, eukaryotes (plants, animals, fungi and protists) and archaea.

In 1987, Woese wrote about the consequences of rampant horizontal gene transfer. In such a scenario, "a bacterium would not actually have a history in its own right: It would be an evolutionary chimera."

A "chimera" is the name of a creature from Greek mythology that mixed together features of a lion, a goat and a snake. This hybridization presumably gave the chimera an advantage over its "competitors."

In a 2006 PNAS paper, Kalin Vetsigian, Woese and Goldenfeld showed that microbial chimeras may also have an advantage over their biological counterparts. The researchers used computer models to demonstrate that the genetic code could evolve more efficiently if organisms shared their genes collectively. Horizontal gene transfer turned out to be a better "innovation-sharing protocol" than vertical (Darwinian) transfer.

Now, with his NAI team, Goldenfeld wants to confirm these simulations with genetic studies. Specifically, they will target archaea, whose genes have yet to be scrutinized as closely as those from the other domains, Goldenfeld said.

The group is particularly interested in the question of how the ability to evolve originally developed. The "evolution of evolution" sounds like a chicken-and-egg problem — especially if you think, as Goldenfeld does, that life is by definition something capable of evolving.

However, evolution can utilize different mechanisms to achieve the same goal. Goldenfeld's team will try to recover some of life's former evolutionary phases by stressing cells and then seeing how their genomes rearrange in response.

Universal biology

However, DNA evidence is just one aspect of this five-year research project.

"We want to understand how evolution works before there were species or maybe even genes," Goldenfeld said. "So this is going beyond 'origin of species' approaches to evolution, such as population genetics."

How does one study evolution without genetics? One considers the "rules of the game" that the genetic code is just one manifestation of. Goldenfeld calls this "universal biology." It is an attempt to distill from our specific biochemistry the general physical laws that animate matter.

Being a physicist, Goldenfeld gives the example of thermodynamics. Life must obey conservation of energy and the law of increasing entropy, which will certainly influence how organisms optimize their use of resources.

Other rules involve how to control the amount of variation in the genome from one generation to the next. Too little variation, and organisms can't adapt to changes in the environment. Too much variation, and organisms can't retain useful traits.

The team can place different sets of rules into a computer simulation and see what sort of artificial life appears. Goldenfeld believes that formulating the principles of universal biology may help answer one of the biggest questions of all.

"We would like to have a better understanding of why life exists at all." Goldenfeld said. "Is it a phenomenon that should be generic, like the formation of a crystalline solid, or is it something rare and bizarre?"

This is of special interest to astrobiologists, who wonder about the likelihood that we are not alone. If life is eventually found elsewhere, Goldenfeld thinks we'll have a few things in common.

"The principles of universal biology should be applicable to all life irrespective of whether it is carbon chemistry-based or something stranger," he said.

Something stranger? Okay, so maybe that means they won't be in the phone book.

Friday, 29 March 2013

Seasons on 'Game of Thrones' Planet: How They Work

Winter is coming on the HBO series "Game of Thrones," but no one seems to be able to predict when.

The planet's last summer persisted for seven years, while winter has been known to last a generation on the show. Understanding when the seasons will change is just one of the many issues plaguing the characters of the fantasy series based on the books by George R.R. Martin.

Although science doesn't play much of a role in the fictional world — which comes complete with dragons, magic and a red comet that serves as an omen — planetary science could help explain the odd seasonal changes on the three continents in the TV show's universe.

"Yes, seasons can last arbitrarily long times," Geoff Marcy, a veteran planet hunter at the University of California, Berkeley, wrote in an email to SPACE.com.

Seasons are for the most part controlled by the way a planet leans toward or away from its sun. For example, the Earth's axis does not run straight through the planet. Instead, it has a slight tilt that points the Northern Hemisphere toward the sun during part of the planet's orbit (causing summer) and away for another part (causing winter).

Other planets experience similar — and more extreme — seasonal changes.

"The planet Uranus in our solar system has its North Pole spin axis pointed toward the sun during some 42 years, and then it points away from the Sun for another 42 years," wrote Marcy. "If you lived anywhere in the northern hemisphere, summer would last 42 years and then winter would last 42 years. So the spin axis orientation makes all the difference."

Although Uranus' winter and summer might be extremely long, they are still predictable. On "Game of Thrones," no one knows when summer will end and winter will begin. It is possible that a "wobbly" axis could create variable seasonal length, said Greg Laughlin, an astrophysicist at the University of California Santa Cruz, but not necessarily on the timeline that show presents.

A wobbly tilt will not create rapid seasonal changes over the course of years or even decades, Laughlin said. Variability in the length of season happens after thousands of years. In other words, the characters on the television show would not be alive to see a distinct change in the length of any of the seasons.

Mars has a wobbly axis, according to Marcy. However, the Red Planet's seasons don't change from one year to the next. Instead, it takes thousands of years for the planet's axis to wobble enough to change the length of a season.

Seasons are also dependent upon the kind of planetary system the exoplanet finds itself in, Laughlin said.

"One situation that will lead to wildly variable seasons over long periods of time is if the planet in question is a member of a strongly interacting multiple planet system," Laughlin said, describing how a planet's orbit could be pulled out of whack by another planet.

These changes would also happen over the course of thousands or millions of years, Laughlin added. But this also might be a good explanation for the seasonal issues on the "Game of Thrones."

The books and TV show make mention of a second moon that disintegrated when it flew too close to its sun. Of course, in the book's lore that moon was actually an egg full of dragons … so maybe it would be best not to apply too much real science to this kind of fiction.

The newest season of "Game of Thrones" premieres Sunday (March 31) at 9 p.m. EDT on HBO. Check local listings.

Why You Are Paying for Everyone's Flood Insurance

There are many, many compelling and urgent reasons to take decisive action to combat climate change. Here's one that's measurable by dollars added to our budget deficit. Actually by tens of billions of dollars.

The soaring cost of private flood insurance is pricing so many coastal homeowners out of the market that the rest of the American taxpayers are having to bail them out – to the tune of $30 billion under the National Flood Insurance Program (NFIP).

With over $139 billion in storm, wildfire, drought, tornado and flood damages taking nearly 1 percent of U.S. gross domestic product (GDP) in 2012, the insurance industry is referring to last year as the second costliest year on record for U.S. climate-related disasters. And while insurers do include $12 billion worth of flood-related damages in their estimates, they aren't the ones getting stuck with most of the bill. It's us, the taxpayer.

On a global basis, the insurance company Munich Re estimates that flooding represented 16 percent of total climate-related damages over the past decade, or $25 billion, on average, per year. Over that same period, insurers paid out on $3.75 billion per year, on average, or less than 15 percent of total flood-related costs. That percentage seems to be fairly representative as the total losses from floods along the Mississippi in 2011 were estimated at $4.6 billion with only $500 million (11 percent) covered by private insurers.

So if insurers are only paying 10-15 percent of the bill, who actually does pay the cost of flood-related damage? The not-so-surprising answer is you and me, largely through the National Flood Insurance Program, which has nearly $1.3 trillion in policies outstanding. This program includes several state programs, such as the one for Florida (which has over 2 million policy holders and a face value of $475 billion) that had to be created as the rising cost of flooding was not being covered by private insurers.

This massive federal program has nearly doubled in size over the past decade as private insurers have continued to shy away from making bets against Mother Nature when it comes to floods. And while the federal government has picked up the slack in terms of coverage, it has had a tough time balancing the premiums that are paid in with the heavy losses it has sustained from recent climate related events.

In fact, following an estimated $12 billion in payout to 140,000 policy holders from Superstorm Sandy, the program is over $30 billion in debt and has Congress scratching its head about what to do about it since the private insurers have made it very clear this is not a business that they wish to be in. NFIP is insolvent because premiums don't reflect actual risks; and it's hard to make a case that climate-change-charged storms are not a big part of the reason why.

In sum, the U.S. taxpayer is currently down $30 billion trying to provide insurance for coastal landowners that no longer have access to affordable private flood insurance. And that figure does not include the costs weathered by the state-based programs that have been set up due to a lack of private alternatives available to their residents. Taken together, these programs constitute a climate disruption tax that the U.S. consumer is being forced to pay to cover risks that the insurance industry, the true score-keepers on climate, won't touch.

As the costs of climate change continue to mount, it is becoming increasingly obvious that we can't afford not to act to rein in the carbon pollution that is supercharging storms and floods. Fortunately President Obama has a big opportunity to reduce emissions from power plants, America's biggest carbon polluters. Under a plan NRDC put forward in December, we could cut these emissions by 26 percent by 2020 and 34 percent by 2025 compared to 2005 levels. The plan provides great flexibility to states and utilities, and offers benefits to every American.

Its benefits—worth between $25 and $60 billion in 2020 — far outweigh the plan's costs — about $4 billion. Implementing it will save tens of thousands of lives through reductions in air pollution. And it will drive investments in energy efficiency and clean energy that will create thousands of new jobs across the nation. Now that's an insurance premium worth paying.

It Pays to Shop Around for Prescription Drugs, Study Finds

The next time your doctor writes you a prescription for a new generic drug, channel your inner bargain hunter and shop around, as it could save you a lot of money, a new survey from Consumer Reports has found.

When secret shoppers called more than 200 pharmacies around the United States to check the total price for a month's supply of five top-selling prescription drugs that recently went generic, they discovered an overall 447 percent difference — or $749 — between the highest- and lowest-priced stores.

"When blockbuster drugs go generic, a lot of irrational pricing happens," said Lisa Gill, editor of prescription drugs at Consumer Reports.

For the survey, secret shoppers gathered pricing information for five blockbuster drugs that had recently gone off patent, which allowed generic versions to enter the marketplace: Actos (pioglitazone), prescribed for diabetes; Lexapro (escitalopram), an antidepressant; Lipitor (atorvastatin), prescribed for high cholesterol; Plavix (clopidogrel), a blood thinner; and Singulair (montelukast), an asthma medication.

Pharmacies surveyed included big-box stores, like Costco and Walmart; national chain pharmacies, such as CVS and Walgreens; online retailers HealthWarehouse.com and FamilyMeds.com; supermarket pharmacies; and smaller, independent pharmacies.

Overall, Costco had the lowest prices for each of the generic drugs checked. What's more, people didn't have to join the club to use the pharmacy, Gill said.

Some of the smaller, independent pharmacies also offered affordable prescriptions.

"That was the real shocker," Gill said. "Prices at independent pharmacies were all over the map for these drugs."

Among the national chain stores, CVS, Rite Aid and Target were the priciest, according to the survey.

For example, a month's supply of Actos (30 mg dose) was $101 at Costco, compared with $160 at Walmart and $295 at CVS. Prices at independent pharmacies and supermarkets ranged from $37 to $393. The cost was $141 and $140, respectively, at HealthWarehouse.com and FamilyMeds.com.

At Costco, a month's supply of Singulair (10 mg dose) was $27, compared with $57 at Walmart and $165 at CVS. Prices at independent pharmacies and supermarkets ranged from $10 to $193. Both HealthWarehouse.com and FamilyMeds.com charged $29.

Location also affected pricing, with urban pharmacies tending to have higher prices than rural ones. For instance, an independent pharmacy in Raleigh, N.C., charged $203 for a 30-day supply of Actos, while a rural North Carolina store charged just $37, Gill said.

Why prices vary

One reason for the lower costs at big-box stores is that their pharmacies are intended to "build traffic," said Stephen W. Schondelmeyer, professor of pharmacy economics at the University of Minnesota in Minneapolis, who was not involved in the survey. In those stores, pharmacy sales account for less than 5 percent of total revenues, he added.

By contrast, big chains like CVS and Walgreens, as well as independent pharmacies, rely on prescription sales to make up a bigger chunk of their revenues — in turn, bumping up prices at those stores, Schondelmeyer explained.

However, consumers may be willing to pay more at other stores because they offer convenience or other perks, Gill said. For example, Costco pharmacies are generally open from 10 a.m. until 7:00 or 8:30 p.m. and are often closed on Sundays, the survey found. By contrast, CVS has a 24-hour pharmacy service, automated prescription refills and drive-through windows. Also, stores like CVS and Rite Aid have more locations than Costco, allowing consumers to save time and gas.

Money-saving strategies

The wide range of prices found in the survey is not the norm for generic drugs that have been on the market for more than a year, Schondelmeyer said. Therefore, the time to comparison-shop is when a popular drug first goes off patent. Typically, the prescription price will drop to about one-tenth of its name-brand price during the first year it is on the market, and then stabilize.

Gill gave the following tips for keeping prescription drug costs down:

Go generic, if possible. Generic drugs usually cost less than brand-name drugs.

Request the lowest price. Don't assume the first price quoted is the lowest, Gill said.
Some of Gill's secret shoppers told pharmacy employees they were paying out of pocket and asked if a better price were available. In some cases, it was. Also, ask about student and senior discounts.

Visit smaller towns. Urban areas are generally pricier than rural areas.

Ask for a 90-day supply instead of a 30-day refill. Discounts on three-month supplies are common.

Consider paying the retail price. The survey found that Costco, drugstore websites and some independent pharmacies charged less than the co-pay of some insurance companies.

Check out additional discounts. Many chain pharmacies, big-box stores, club stores and large supermarkets have discount prescription programs, Gill said. For example, Walmart charges $4 for a 30-day supply of some generic medications, but $10 for a 90-day supply. She noted that the programs may not include every dosage of a drug, and many do not allow people to use insurance to pay for the drugs.

Schondelmeyer cautioned against pharmacy-hopping, no matter how tempting the deal is.

"I am all for consumers being wise shoppers, but it is important that people get all their medications from one pharmacy," he said. That way, the pharmacist can check for possible drug interactions and make sure one drug doesn't cancel out the benefits of another.

Pass It On: Shoping around for prescription drugs can save you money.

No Link Between 'Too Many Vaccines' and Autism Risk

Despite concerns by some parents that their children receive "too many vaccines too soon," a new study finds that many shots, even on the same day, do not increase the risk of autism.

In the first six months of life, children receive as many as 19 vaccine doses of six different vaccines, and by the time they are 6 years old, a total of 25 doses from 10 vaccines.

In a 2011 survey, about a third of parents expressed concerns that their child received too many vaccines before age 2, and too many vaccines on a single day.

Previous studies have found no link between the number of vaccines a child receives and their risk of several neurological conditions (though these studies did not specifically consider autism).

The new study went a step further by looking at the link between a child's total exposure to antigens — the proteins in vaccines that stimulate the body's immune system — and his or her risk of autism.

The researchers looked at total antigen exposure rather than the total number of vaccines kids received because, at the root of parents' concerns is the idea that "somehow they provide too much immunological stimulation, more so than a young child's immune system can handle," said study researcher Dr. Frank DeStefano, of the Centers for Disease Control and Prevention. (The sheer number of vaccines would not be as good a measure of immunological response because vaccines contain different numbers of antigens, and some protect against more than one disease, DeStefano said.)

DeStefano and colleagues analyzed information from about 250 children with autism and 750 children without autism, born between 1994 and 1999.

Children with autism were exposed to about same total number of antigens as children without autism at ages 3 months, 7 months and 2 years. There was also no difference between the two groups in terms of the total number of antigens they were exposed to on a single day.

"Parental concerns that their children are receiving too many vaccines in the first two years of life, or too many vaccines at a single doctor visit are not supported in terms of an increased risk of autism," the researchers write in the March 29 issue of the Journal of Pediatrics.

Kids are exposed to many viruses and other pathogens that stimulate their immune systems in the same way vaccines do, and it's been estimated that kids could theoretically receive thousands of vaccines at once, the researchers said.

Although children today receive more vaccines than children in the mid-90s, the vaccines used today contain fewer antigens. So while children in the mid-90s were exposed to between 3,000 and 15,250 antigens in the first two years of life, children today are exposed to about 315 antigens, the researchers said.

Pass it on: The multiple vaccine doses kids receive early in life do not increase their risk of autism.