Science – Page 34 – artdiamondblog.com

How Electricity Matters for Life

Source of book image:
http://media.npr.org/assets/bakertaylor/covers/t/the-spark-of-life/9780393078039_custom-86637e64da2201ed3081e0f26f40e0d139cbbf9d-s6-c10.jpg

(p. C9) Top-drawer scientists always are excited about their field, but many have difficulty conveying this to a general audience. Not so Frances Ashcroft. She is a distinguished physiologist at Oxford University whose work has provided crucial insight into how insulin secretion is connected to electrical activity in cells. Her research has meant that children born with one form of diabetes can control it using oral medication instead of regular and painful insulin injections.

After Ms. Ashcroft made her breakthrough in 1984, she felt as if she were “dancing in the air, shot high into the sky on the rocket of excitement with the stars exploding in vivid colours all around me,” she writes in her engaging and informative “The Spark of Life: Electricity in the Human Body.” Even today, thinking of it “sends excitement fizzing through my veins.”
Like so much else in our bodies, insulin secretion depends on crucial proteins in the cell walls that regulate the flow of ions (electrically charged atoms or molecules) between the interior of the cell and the fluids that surround it. The ions, mostly sodium, potassium and calcium, literally provide “the spark of life.” Ms. Ashcroft uses her research into cellular “ion channels” as an overture to a rich and stimulating account of how electricity and the varied ways in which animals and plants produce it explain so much of evolutionary biology.
. . .
. . . all of Ms. Ashcroft’s themes and variations represent facets of the same underlying ionic mechanism. In describing its wonders, she has produced a gem that sparkles.

For the full review, see:
WILLIAM BYNUM. “Singing the Body Electric.” The Wall Street Journal (Sat., September 29, 2012): C9.
(Note: ellipses added.)
(Note: the online version of the review has the date September 28, 2012.)

The book under review, is:
Ashcroft, Frances. The Spark of Life: Electricity in the Human Body. New York: W. W. Norton & Company, 2012.

Scientists May Bring Back Extinct Woolly Mammoths to Help Fight Global Warming

“The Southern gastric brooding frog, extinct for a quarter-century. Scientists made early embryos of the frog but they died.” Source of caption and photo: online version of the NYT article quoted and cited below.

(p. A1) Last week at a conference in Washington, scientists from Australia reported on their attempt to bring back a weird frog, the Southern gastric brooding frog, that went extinct about a quarter century ago. So far they have only made early embryos, which have died.

It is the early days for this new endeavor — it could be years before scientists succeed in bringing species back from extinction. But many species are now gleams in scientists’ eyes as they think of ways to bring them back. Woolly mammoths. A 70,000-year-old horse that used to live in the Yukon. Passenger pigeons, a species that obsessed Dr. Church’s former student.
. . .
(p. A16) Before humans killed them, the nation had three billion to five billion passenger pigeons. They would take days to cross a city, noted Hank Greely, the director of the Stanford Center for Law and the Biosciences at Stanford University. “They left cities covered in an inch of guano,” he said.
. . .
But there could be some unexpected advantages to bringing back certain species, or even to adding their DNA to that of today’s species, Dr. Church said. For example, suppose elephants could live again in the Arctic. When woolly mammoths lived in the Arctic they would knock down trees and enable Artic grasses to flourish. Without trees, more sunlight was reflected and the ground was cooler. In winter, they would tramp down snow into the permafrost, enhancing it.
“Permafrost has two to three times more carbon than all the rain forests put together,” Dr. Church said. “All you have to do to release carbon dioxide and methane is to melt it. With rain forests you have to burn it.”
. . .
Mr. Greely cited another argument in favor of bringing back extinct species. He did not quite buy it, he said, but for him it had “a visceral appeal.”
It is an argument about justice. Take the passenger pigeon. “We are the murderers,” Mr. Greely said. “We killed them off. Shouldn’t we bring them back?”

For the full story, see:
GINA KOLATA. “So You’re Extinct? Scientists Have Gleam in Eye.” The New York Times (Tues., March 19, 2013): A1 & A16.
(Note: the online version of the story has the date March 18, 2013.)
(Note: ellipses added.)

Global Warming Causes Trees to Grow Faster and Absorb More CO2

“CITY TREE, COUNTRY TREE; Scientists have been looking more closely at urban plant growth in places like Central Park.” Source of caption and photo: online version of the NYT article quoted and cited below.

(p. D3) . . . , some . . . scientists have moved beyond political questions to explore how rising levels of heat and emissions might provide at least some benefits for the planet.
. . .
Lewis H. Ziska, a plant physiologist for the Department of Agriculture, . . . [said] . . . , “we need to think about the tools we have at hand, and how we can use them to make climate change work for us.”
Among the tools are cities, which have conditions that can mimic what life may be like in the temperate zone of a heated planet.
“The city is our baseline for what might happen in future decades, and with all the negative effects global warming may have, there may be a bit of a silver lining,” said Stephanie Searle, a plant physiologist who led a Columbia University research project on tree growth, and now works as a biofuels researcher at the nonprofit International Council on Clean Transportation. “Higher nighttime temperatures, at least, may boost plant growth.” Robust growth takes more carbon dioxide out of the atmosphere.
. . .
The effects of higher, mostly urban emissions are what prompted Dr. Ziska to reappraise global warming as a potential benefit to humanity. In an essay last summer in the journal Proceedings of the Royal Society B, Dr. Ziska and a group of colleagues from across the world argued that an expected increase in world population to 9 billion people from 7 billion by 2050 necessitated a “green revolution” to enhance yields of basic grains. Carbon dioxide, the group suggested, could be the answer.
Since 1960, world atmospheric carbon dioxide concentrations have risen by 24 percent to 392 parts per million and could reach 1,000 parts per million by the end of this century.
. . .
In New York, the Columbia researchers studied for eight years the growth of red oak seedlings at four locations, including an “urban” site near the northeastern edge of Central Park at 105th Street and a “remote” site in the Catskills 100 miles north of Manhattan near the Ashokan Reservoir.
. . .
The Columbia team’s first red oak experiments ended in 2006, and average minimum temperatures in August were 71.6 degrees at the city site, but 63.5 degrees in the Catskills. Researchers also noticed that the city oaks had elevated levels of leaf nitrogen, a plant nutrient.
The team did two more rounds of experiments, then in 2008 made a final outdoor test using fertilized rural soil everywhere so all the seedlings got plenty of nitrogen. The urban oaks, harvested in August 2008, weighed eight times as much as their rural cousins, mostly because of increased foliage.
“On warm nights, the tree respires more,” Dr. Griffin said. “It invests its carbon sugars to build tissue.” By morning, the tree’s sugars are depleted, and it has to photosynthesize more during the day, he continued. The tree grows more leaves and gets bigger.

For the full story, see:
GUY GUGLIOTTA. “Looking to Cities, in Search of Global Warming’s Silver Lining.” The New York Times (Tues., November 27, 2012): D3.
(Note: ellipses and bracketed “said” added.)
(Note: the online version of the story has the date November 26, 2012.)

The Ziska article mentioned above, is:
Ziska, Lewis H., James A. Bunce, Hiroyuki Shimono, David R. Gealy, Jeffrey T. Baker, Paul C. D. Newton, Matthew P. Reynolds, Krishna S. V. Jagadish, Chunwu Zhu, Mark Howden, and Lloyd T. Wilson. “Food Security and Climate Change: On the Potential to Adapt Global Crop Production by Active Selection to Rising Atmospheric Carbon Dioxide.” Proceedings of the Royal Society B: Biological Sciences 279, no. 1745 (Oct. 22, 2012): 4097-105.

The article co-authored by Searle and Griffin, and mentioned above, is:
Searle, Stephanie Y., Danielle S. Bitterman, Samuel Thomas, Kevin L. Griffin, Owen K. Atkin, and Matthew H. Turnbull. “Respiratory Alternative Oxidase Responds to Both Low- and High-Temperature Stress in Quercus Rubra Leaves Along an Urban-Rural Gradient in New York.” Functional Ecology 25, no. 5 (Oct. 2011): 1007-17.

Scientist Sees Benefits in Plan to Increase Global Warming

(p. D2) Plants are . . . part of one theoretical plan for turning Mars into a suitable environment for human beings, a process called terraforming.
. . .
Chris McKay, a Mars expert at the NASA Ames Research Center, theorizes that engineers would first have to encourage the kind of global warming they want to avoid on Earth. This could be done by releasing greenhouse gases, like chlorofluorocarbons or perfluorocarbons, into the atmosphere. The goal would be to increase the surface temperature of Mars by a total of about 7.2 degrees Fahrenheit.
. . .
With the rise in temperature, heat-trapping carbon dioxide would eventually be released from the planet’s south polar ice cap, producing a further average temperature rise of even greater magnitude, perhaps as much as 70 degrees Celsius, or 126 degrees Fahrenheit.
These high temperatures would melt ice to produce the water needed for living things.

For the full story, see:
C. CLAIBORNE RAY. “Q & A; At Home on Mars.” The New York Times (Tues., December 11, 2012): D2.
(Note: ellipses added.)
(Note: the online version of the story has the date December 10, 2012.)

McKay wrote up some of his ideas in:
McKay, Christopher P. “Bringing Life to Mars.” Scientific American Presents: The Future of Space Exploration (1999): 52-57.

NYT Climate Blogger Sees Evidence “Trending” Toward Less Global Warming

“Worse than we thought” has been one of the most durable phrases lately among those pushing for urgent action to stem the buildup of greenhouse gases linked to global warming.
But on one critically important metric — how hot the planet will get from a doubling of the pre-industrial concentration of greenhouse gases, a k a “climate sensitivity” — some climate researchers with substantial publication records are shifting toward the lower end of the warming spectrum.
There’s still plenty of global warming and centuries of coastal retreats in the pipeline, so this is hardly a “benign” situation, as some have cast it.
But while plenty of other climate scientists hold firm to the idea that the full range of possible outcomes, including a disruptively dangerous warming of more than 4.5 degrees C. (8 degrees F.), remain in play, it’s getting harder to see why the high-end projections are given much weight.
. . .
In fact, there is an accumulating body of reviewed, published research shaving away the high end of the range of possible warming estimates from doubled carbon dioxide levels.
. . .
(. . . recent work is trending toward the published low sensitivity findings from a decade ago from climate scientists best known for their relationships with libertarian groups.)
Nonetheless, the science is what the science is.

Revkin, Andrew C. “CLIMATE CHANGE; A Closer Look at Moderating Views of Climate Sensitivity.” Dot Earth: New York Times Opinion Pages Climate Blog. (posted February 4, 2013).
(Note: ellipses added.)

Resveratrol Activates Sirtuins to Switch on Energy Producing Mitochondria

A new study, just published in the prestigious journal Science, appears to substantially vindicate the recently beleaguered resveratrol longevity research of David Sinclair:

. . . a new study led by David Sinclair of the Harvard Medical School, who in 2003 was a discoverer resveratrol’s role in activating sirtuins, found that resveratrol did indeed influence sirtuin directly, though in a more complicated way than previously thought. . . . . . . activated, the sirtuins do several things, one of which is to switch on a second protein that spurs production of the mitochondria, which provide the cell’s energy. This would explain why mice treated with resveratrol ran twice as far on a treadmill before collapsing from exhaustion as untreated mice.

For the full story, see:
NICHOLAS WADE. “New Optimism on Resveratrol.” New York Times “Well” Blog Posted on MARCH 11, 2013. URL: http://well.blogs.nytimes.com/2013/03/11/new-optimism-on-resveratrol/
(Note: ellipses added.)

The Sinclair article (see last-listed co-author) is:
Hubbard, Basil P., Ana P. Gomes, Han Dai, Jun Li, April W. Case, Thomas Considine, Thomas V. Riera, Jessica E. Lee, Sook Yen E (sic), Dudley W. Lamming, Bradley L. Pentelute, Eli R. Schuman, Linda A. Stevens, Alvin J. Y. Ling, Sean M. Armour, Shaday Michan, Huizhen Zhao, Yong Jiang, Sharon M. Sweitzer, Charles A. Blum, Jeremy S. Disch, Pui Yee Ng, Konrad T. Howitz, Anabela P. Rolo, Yoshitomo Hamuro, Joel Moss, Robert B. Perni, James L. Ellis, George P. Vlasuk, and David A. Sinclair. “Evidence for a Common Mechanism of Sirt1 Regulation by Allosteric Activators.” Science 339, no. 6124 (March 8, 2013): 1216-19.

Stanford Meta-Study Finds Organic Food Is No More Nutritious than Much Cheaper Non-organic Food

“Conventional strawberries in Watsonville, California. Researchers say organic foods are no more nutritious and no less likely to be contaminated.” Source of caption and photo: online version of the NYT article quoted and cited below.

(p. A20) Does an organic strawberry contain more vitamin C than a conventional one?

Maybe — or maybe not.
Stanford University scientists have weighed in on the “maybe not” side of the debate after an extensive examination of four decades of research comparing organic and conventional foods.
They concluded that fruits and vegetables labeled organic were, on average, no more nutritious than their conventional counterparts, which tend to be far less expensive. Nor were they any less likely to be contaminated by dangerous bacteria like E. coli.
The researchers also found no obvious health advantages to organic meats.
. . .
The conclusions will almost certainly fuel the debate over whether organic foods are a smart choice for healthier living or a marketing tool that gulls people into overpaying. The production of organic food is governed by a raft of regulations that generally prohibit the use of synthetic pesticides, hormones and additives.
The organic produce market in the United States has grown quickly, up 12 percent last year, to $12.4 billion, compared with 2010, according to the Organic Trade Association. Organic meat has a smaller share of the American market, at $538 million last year, the trade group said.
. . .
In the study — known as a meta-analysis, in which previous findings are aggregated but no new laboratory work is conducted — researchers combined data from 237 studies, examining a wide variety of fruits, vegetables and meats. For four years, they performed statistical analyses looking for signs of health benefits from adding organic foods to the diet.
The researchers did not use any outside financing for their research. “I really wanted us to have no perception of bias,” Dr. Bravata said.

For the full story, see:
KENNETH CHANG. “Stanford Scientists Cast Doubt on Advantages of Organic Meat and Produce.” The New York Times (Tues., September 4, 2012): A20.
(Note: ellipses added.)
(Note: the online version of the story has the date September 3, 2012.)

Organic Food May Be Less Healthy than Non-Organic Food

Source of book image: http://www.leckeragency.com/sites/default/files/books/Schwarcz,%20Joe%20-%20The%20Right%20Chemistry%20Cover.jpeg

(p. D7) . . . , when did “chemical” become a dirty word? That’s a question raised by one of Canada’s brightest scientific minds: Joe Schwarcz, director of the Office for Science and Society at McGill University in Montreal. Dr. Schwarcz, who has received high honors from Canadian and American scientific societies, is the author of several best-selling books that attempt to set the record straight on a host of issues that commonly concern health-conscious people.

I’ve read two of his books, “Science, Sense and Nonsense” (published in 2009) and “The Right Chemistry” (2012), and recently attended a symposium on the science of food that Dr. Schwarcz organized at McGill.
What follows are tips from his books and the symposium that can help you make wiser choices about what does, and does not, pass your lips in 2013.
. . .
ORGANIC OR NOT? Wherever I shop for food these days, I find an ever-widening array of food products labeled “organic” and “natural.” But are consumers getting the health benefits they pay a premium for?
Until the 20th century, Dr. Schwarcz wrote, all farming was “organic,” with manure and compost used as fertilizer and “natural” compounds of arsenic, mercury and lead used as pesticides.
Might manure used today on organic farms contain disease-causing micro-organisms? Might organic produce unprotected by insecticides harbor cancer-causing molds? It’s a possibility, Dr. Schwarcz said. But consumers aren’t looking beyond the organic sales pitch.
Also questionable is whether organic foods, which are certainly kinder to the environment, are more nutritious. Though some may contain slightly higher levels of essential micronutrients, like vitamin C, the difference between them and conventionally grown crops may depend more on where they are produced than how.
A further concern: Organic producers disavow genetic modification, which can be used to improve a crop’s nutritional content, enhance resistance to pests and diminish its need for water. A genetically modified tomato developed at the University of Exeter, for example, contains nearly 80 times the antioxidants of conventional tomatoes. Healthier, yes — but it can’t be called organic.

For the full story, see:
JANE E. BRODY. “PERSONAL HEALTH; What You Think You Know (but Don’t) About Wise Eating.” The New York Times (Tues., January 1, 2013): D7.
(Note: ellipses added; bold in original.)
(Note: the online version of the article has the date DECEMBER 31, 2012.)

The Schwarcz books mentioned above, are:
Schwarcz, Joe. The Right Chemistry: 108 Enlightening, Nutritious, Health-Conscious and Occasionally Bizarre Inquiries into the Science of Daily Life. Toronto, Ontario: Doubleday Canada, 2012.
Schwarcz, Joe. Science, Sense & Nonsense. Toronto, Ontario: Doubleday Canada, 2009.

Darwin Shared His Thought Processes Without Condescension

“SAGE OF AGES; Portrait of Charles Darwin in 1881, by Julia Margaret Cameron.” Source of caption and photo: online version of the WSJ article quoted and cited below.

(p. C14) . . . Mr. Johnson observes:

No scientific innovator has ever taken more trouble to smooth the way for lay readers without descending into vulgarity. What is almost miraculous about the book is Darwin’s generosity in sharing his thought processes, his lack of condescension. There is no talking down, but no hauteur, either. It is a gentlemanly book.

In both style and substance, this passage is classic Paul Johnson.
. . .
What makes Darwin good, in the biographer’s estimation, is the scientist’s democratic dissemination of knowledge. Darwin triumphed with “The Origin of Species,” Mr. Johnson contends, not only because of his ability to portray the theory of evolution as the inescapable outcome of his decades of study and the work of fellow scientists, whom he was careful to praise, but because he was acutely aware that he had to present his notions of natural selection and survival of the fittest so as not to stir up public controversy. To an extraordinary degree, Darwin deflected attacks by couching his discoveries in terms of the plants he liked to examine and cultivate. He had relatively little to say about human evolution.

For the full review, see:
CARL ROLLYSON. “Studies of the Moral Animal.” The Wall Street Journal (Sat., December 15, 2012): C14.
(Note: ellipses added.)
(Note: the online version of the review essay has the date December 14, 2012.)

The book under review is:
Johnson, Paul M. Darwin: Portrait of a Genius. New York: Viking Adult, 2012.

Lichen Fungi May Never Age

“ANNUAL VISITOR; For the last eight years, Anne Pringle of Harvard has been collecting data about the lichens on the gravestones at a cemetary in Petersham, Mass.” Source of caption and photo: online version of the NYT article quoted and cited below.

(p. D3) PETERSHAM, Mass. — On a sparkling New England afternoon, as hawks coasted overhead and yellow leaves drifted to the ground, Anne Pringle stood before a large granite obelisk that marked the graves of a family called French.
. . .
For eight years, Dr. Pringle, 42, has been returning to this cemetery each fall, to measure, sketch and scrutinize the lichens, which belong to the genus Xanthoparmelia. She wants to know whether they deteriorate with the passage of time, leaving them more susceptible to death.
. . .
Lichens are not individuals but tiny ecosystems, composed of one main fungus, a group of algae and an assortment of smaller fungi and bacteria.
. . .
While lichens are communities, Dr. Pringle is largely interested in the fungi. Mycologists, the scientists who study fungi — not the most glamorous corridor of biology — have long assumed that many of these organisms don’t age.
. . .
“What you know is based on the organisms you study,” she said. “What would you say about the evolution of senescence if instead of working with insects, you worked with modular organisms, which is what lichen are?”
Daniel Doak, a University of Colorado ecologist, agrees that the question is worth asking. Research like Dr. Pringle’s — along with other studies of species including the bristlecone pine tree and the wandering albatross, a bird, both of which may avoid senescence — suggests another possible path.
“It’s saying something fundamental,” Dr. Doak said, “that senescence is not an inevitable part of life. Which means there might be ways to prevent it.” That idea could eventually have implications for human medicine.
. . .
Dr. Pringle’s preliminary results show that as a lichen grows older and larger, it is less likely to die. “If you made me answer the question now,” she said, “I’d say there can be senescence of parts of an individual. But I don’t think an individual ever senesces.”

For the full story, see:
HILLARY ROSNER. “In a Place for the Dead, Studying a Seemingly Immortal Species.” The New York Times (Tues., January 1, 2013): D3.
(note: ellipses added.)
(Note: the online version of the story has the date December 31, 2012.)

“THRIVING; Dr. Pringle’s initial results show that as a lichen grows older and larger, it is less likely to die.” Source of caption and photo: online version of the NYT article quoted and cited above.

Social Scientists Prefer Articles that Contain Bogus Math

Source of graphic: online version of the WSJ article quoted and cited below.

(p. A2) . . . research has shown that even those who should be especially clear-sighted about numbers–scientific researchers, for example, and those who review their work for publication–are often uncomfortable with, and credulous about, mathematical material. As a result, some research that finds its way into respected journals–and ends up being reported in the popular press–is flawed.

In the latest study, Kimmo Eriksson, a mathematician and researcher of social psychology at Sweden’s Mälardalen University, chose two abstracts from papers published in research journals, one in evolutionary anthropology and one in sociology. He gave them to 200 people to rate for quality–with one twist. At random, one of the two abstracts received an additional sentence, the one above with the math equation, which he pulled from an unrelated paper in psychology. The study’s 200 participants all had master’s or doctoral degrees. Those with degrees in math, science or technology rated the abstract with the tacked-on sentence as slightly lower-quality than the other. But participants with degrees in humanities, social science or other fields preferred the one with the bogus math, with some rating it much more highly on a scale of 0 to 100.
“Math makes a research paper look solid, but the real science lies not in math but in trying one’s utmost to understand the real workings of the world,” Prof. Eriksson said.

For the full story, see:
CARL BIALIK. “THE NUMBERS GUY; Don’t Let Math Pull the Wool Over Your Eyes.” The Wall Street Journal (Sat., January 5, 2013): A2.
(Note: ellipsis added.)
(Note: the online version of the story has the date January 4, 2013,)

A pdf of Eriksson’s published article can be downloaded from:
Eriksson, Kimmo. “The Nonsense Math Effect.” Judgment and Decision Making 7, no. 6 (November 2012): 746-49.