Sustainable Livestock Production

Written by Science Knowledge on 10:42 PM

Livestock serves as an excellent protein and mineral source for humans, but those nutrients come with a price paid in water. One pound (0.45 kg) of meat protein requires 8,124 gallons (30,744 l) of water to produce. By comparison, the same amount plant protein of equivalent quality requires 3.1 gallons (11.6 l) to produce. Put in another perspective, a pound of sugarcane needs 21 gallons (80 l) of water, but a pound of leather requires 2,000 gallons (7,571 l) of water to produce.

Of all livestock industries, beef production requires the most water and the most rangeland. Feedlots account for almost half of all beef and pork production and three-quarters of poultry production. In terms of efficiency, feedlots that concentrate all animals in pens provide an advantage over free-range production, wherein animals roam outside cages to graze on the land. The United States depends to a large extent on feedlots, using energy dense grains to feed the animals rather than natural grasses, but many people object to this style of factory farming on ethical grounds. The Humane
Society of the United States has explained, “The vast majority of our meat, dairy and eggs comes not from animals on small farms but from factory farms—massive operations that treat animals like profit-making machines, routinely subjecting them to terrible abuses. . . .” Feedlots furthermore produce large amounts of manure, which has the potential to pollute waterways, yet these operations do not spoil the land as grazing often does.

Whether free-range or feedlot-raised, meat production is an inefficient way to produce energy. Meat-producing animals convert grain to animal body weight on a pound-to-pound (kg-to-kg) basis as follows: fish, 2.0; chicken, 2.2; pigs, 4.0, and beef, 7.0. Cattle and sheep present another problem in the environment because they belch large amounts of gas that forms in their normal digestion of fibrous plants. This gas contains about 60 percent methane and 40 percent carbon dioxide, both greenhouse gases. The agriculture and energy industries have studied ways to capture ruminant gasses as an energy source and also so they do not add to global warming. The dairy farmer Richard Huelskamp described the plan clearly in a 2006 interview with the University of Minnesota’s Minnesota Daily: “I believe that agriculture has got to be supplying 25 to 50 percent of our domestic energy. We need to maintain sustainability.” Can meat production be transformed from one of the most inefficient types of production to a sustainable activity?

Dairyman Huelskamp developed a sustainable use for the so-called biomethane his cows produce. A month’s worth of manure from Huelskamp’s farm travels on conveyers into digester tanks where the solids partially decompose and the gases form. The farm recovers the majority of the gas by funneling it to a generator to produce energy. Part of the decomposed manure serves as fertilizer to reduce the farm’s total waste output.

Sustainable meat production incorporates other devices to reduce its ecological footprint. People can contribute by changing their diet to more seafood and poultry and less beef and pork. In the meantime, livestock operations can adopt as many water and soil conservation techniques as possible. Cattle and sheep, though inefficient, offer the following advantages: Freerange animals eat grasses that humans cannot eat; rangeland that supports grazing is usually poor in supporting crops, so does not cause a conflict with plant agriculture; and many of the world’s poorest regions have access only to cattle as a reliable protein source.

The Worldwatch Institute predicts meat consumption will increase 2 percent per year until at least the year 2015. For this reason, sustainable livestock farming seems a necessity. The future of sustainable livestock raising will likely consist of the following
methods: raising livestock with free-range methods rather than with feedlots to decrease waste loads; incorporating goats with cattle to more efficiently use all rangeland for meat production; raising grains on the farm using water and soil conservation and to reduce fuel use; selling only to local meat producers to reduce transport fuel consumption and emissions; and designing operations to produce less beef and pork and substitute with other products to maintain the farm’s income.

Source of Information : Green Technology Conservation Protecting Our Plant Resources

The Real Science behind Scientology

Written by Science Knowledge on 9:51 PM

It’s not what you think

In the 1990s I had the opportunity to dine with the late musician Isaac Hayes, whose career fortunes had just made a stunning turnabout upward, which he attributed to Scientology. It was a glowing testimonial by a sincere follower of the Church, but is it evidence that Scientology works? Two recently published books argue that there is no science in Scientology, only quasireligious doctrines wrapped in New Age flapdoodle masquerading as science. The Church of Scientology, by Hugh B. Urban, professor of religious studies at Ohio State University, is the most scholarly treatment of the organization to date, and investigative journalist Janet Reitman’s Inside Scientology is an electrifying read that includes eye-popping and well-documented tales of billion-year contracts, aggressive recruitment programs and abuse of staffers.

The problem with testimonials is that they do not constitute evidence in science. As social psychologist Carol Tavris told me, “Every therapy produces enthusiastic testimonials because of the justification-of-effort effect. Anyone who invests time and money and effort in a therapy will say it helped. Scientology might have helped Isaac Hayes, just as psychoanalysis and bungee jumping might have helped others, but that doesn’t mean the intervention was the reason. To know if there is anything special about Scientology, you need to do controlled studies—randomly assigning people to Scientology or a control group (or a different therapy) for the same problem.” To my knowledge, no such study has been conducted. The real science behind Scientology seems to be an understanding of the very human need, as social animals, to be part of a supportive group—and the willingness of people to pay handsomely for it.

If Scientology is not a science, is it even a religion? Well, it does have its own creation myth. Around 75 million years ago Xenu, the ruler of a Galactic Confederation of 76 planets, transported billions of his charges in spaceships similar to DC-8 jets to a planet called Teegeeack (Earth). There they were placed near volcanoes and killed by exploding hydrogen bombs, after which their “thetans” (souls) remained to inhabit the bodies of future earthlings, causing humans today great spiritual harm and unhappiness that can be remedied through special techniques involving an Electropsychometer (E-meter) in a process called auditing.

Thanks to the Internet, this story—previously revealed only to those who paid many thousands of dollars in courses to reach Operating Thetan Level III (OT III) of Scientology—is now so widely known that it was even featured in a 2005 episode of the animated TV series South Park. In fact, according to numerous Web postings by ex-Scientologists, documents from court cases involving followers who reached OT III and abundant books and articles by exmembers who heard the story firsthand and corroborate the details, this is Scientology’s Genesis. So did its founder, writer L. Ron Hubbard, just make it all up—as legend has it—to create a religion that was more lucrative than producing science fiction?

Instead of printing the legend as fact, I recently interviewed the acclaimed science-fiction author Harlan Ellison, who told me he was at the birth of Scientology. At a meeting in New York City of a sci-fi writers’ group called the Hydra Club, Hubbard was complaining to L. Sprague de Camp and the others about writing for a penny a word. “Lester del Rey then said half-jokingly, ‘What you really ought to do is create a religion because it will be tax-free,’ and at that point everyone in the room started chiming in with ideas for this new religion. So the idea was a Gestalt that Ron caught on to and assimilated the details. He then wrote it up as ‘Dianetics: A New Science of the Mind’ and sold it to John W. Campbell, Jr., who published it in Astounding Science Fiction in 1950.”

To be fair, Scientology’s Xenu story is no more scientifically untenable than other faiths’ origin myths. If there is no testable means of determining which creation cosmogony is correct, perhaps they are all astounding science fictions.

Source of Information : Scientific American Magazine

Cholesterol Conundrum

Written by Science Knowledge on 9:43 PM

Changing HDL and LDL levels does not always alter heart disease or stroke risk

Most people who are even a little bit concerned about their cholesterol know that there is a “good” kind—known as HDL— and a “bad” kind—known as LDL. Research has shown that the higher the amount of HDL and the lower the amount of LDL in the blood, the less likely a person is to suffer a heart attack or stroke. As for the one in six Americans with unhealthy cholesterol levels, well, they can always hope to change their luck with a cholesterol-changing medication or two. Or can they?

Two major clinical trials in the past three years have greatly complicated the picture for these and perhaps other folks. The first study, from 2008, shows that lowering LDL levels does not always decrease the risk of having a heart attack. Similarly, results from the second study, released in the spring of this year, show that raising HDL levels does not always translate into fewer heart attacks or strokes.

These perplexing findings do not mean that people should stop taking their cholesterol drugs. The results have, however, underscored the danger of indulging in a common logical shortcut in medical thinking—assuming that artificially producing normal test results in a patient is the same as conferring good health on that patient. For one thing, drugs typically do not mimic normal conditions perfectly. For another, heart attacks and strokes occur after a complex series of processes that may take years to unfold. Simply altering one of these processes does not necessarily fix the whole problem.


GOOD VS. BAD CHOLESTEROL
Still, researchers and physicians, knowing the roles of LDL and HDL in the body, had good reasons to suspect that manipulating the levels could protect against heart attacks and strokes. Despite its bad reputation as a clogger of arteries, the cholesterol molecule is an irreplaceable component of many key parts of the body, from cell membranes to sex hormones. Indeed, this fatty, waxy substance is so important to life that evolution has produced several different mechanisms for transporting it through the bloodstream. Just as oil and water do not mix, neither do waxy cholesterol and watery blood, so cholesterol needs a kind of protective vehicle to surround it and carry it around the body. Two of the most important vehicles for the job are LDL (low-density lipoprotein), which delivers cholesterol to the various cells of the body, including the walls of arteries, and HDL (high-density lipoprotein), which removes cholesterol from the blood. HDL may also act as an antioxidant that reduces unhealthy inflammation in the arteries.

The trouble begins when too much LDL-carried cholesterol winds up in the arterial lining and contributes to the buildup of fatty material, or atherosclerotic plaque. Much of the time the plaque stabilizes without creating too many immediate problems, but sometimes it bursts, triggering blood clots that lead to heart attacks and strokes if the clots prevent blood from delivering critical oxygen to heart or brain tissue. Without oxygen, the affected tissue dies.

People with high LDL levels may form arterial plaques that are more likely to burst. Some people develop extremely high LDL levels because of a genetic disease called familial hypercholesterolemia that severely limits their ability to clear cholesterol from their blood. They suffer heart attacks in their thirties or forties, which is several decades earlier than the average for the general population. On the positive side, those who maintain normal cholesterol levels (LDL less than 100 milligrams per deciliter of blood and HDL cholesterol levels greater than 40 mg/dL)

Source of Information : Scientific American Magazine

You Say Embryo, I Say Parthenote

Written by Science Knowledge on 9:31 PM

Stem cells from unfertilized eggs may be too tightly regulated

U.S. stem cell scientists breathed a sigh of relief this July when a federal judge upheld the Obama administration’s expansion of stem cell research. He ruled that work on existing embryonic stem cell lines derived outside federally funded labs did not violate a ban on the destruction of embryos. Despite the legal victory, however, many investigators remain frustrated that a newer method for creating stem cells remains off-limits for funding.

Human embryonic stem cells typically come from fertilized eggs. In 2007, however, scientists at International Stem Cell, a California-based biotech firm, reported the first successful creation of human stem cell lines from unfertilized eggs. They used a process called parthenogenesis, in which researchers use chemicals to induce the egg to begin developing as if it had been fertilized. The egg—called a parthenote—behaves just like an embryo in the early stages of division. Because it contains no genetic material from a father, however, it cannot develop into a viable fetus.

Just like embryonic stem cells, parthenogenetic stem cells can be coaxed to grow
into different kinds of human cells or tissue, ready to be transplanted into diseased areas of the body. International Stem Cell scientists have converted them into liver cells and plan to convert them into neurons for treating Parkinson’s disease, pancreatic cells for diabetes, and other tissues. Meanwhile teams at the Massachusettsbased Bedford Stem Cell Research Foundation are working to improve the efficiency of methods of deriving stem cells from parthenotes.

Proving that unfertilized eggs will produce stable tissues in humans remains an obstacle, says Alan Trounson, president of the California Institute for Regenerative Medicine. “We need to see this done in other laboratories,” he points out. That won’t be easy. Guidelines from the National Institutes of Health and federal laws define parthenotes as embryos, which means that deriving new parthenogenetic stem cell lines is off-limits to all labs receiving federal funding—which is nearly all of them. Barring an unlikely turnabout, it will be up to a handful of private firms in the U.S. to carry the young field forward.

Source of Information : Scientific American Magazine

Instant Recall

Written by Science Knowledge on 9:24 PM

How many memories do we create in a day?

The series Too Hard for Science? discusses ideas scientists would love to explore that they think are difficult or impossible to investigate.

THE SCIENTIST: Robert Stickgold, director of the Center for Sleep and Cognition at Harvard Medical School.

THE IDEA: How many memories does a person create in one day? Assumptions regarding this number are at the foundation of many studies of the brain. One could put recording equipment on volunteers and compare what they experienced to what they actually remembered about events, Stickgold suggests. This is something he and his colleagues attempted.

THE PROBLEM: One difficulty regards how one counts memories. Is going to the grocery store one memory or a series? Remembrances are fractal in nature: the deeper a person looks into one memory, the more details one can unearth.

Furthermore, Stickgold adds, “There probably really isn’t anything in the brain that’s a discrete memory.” The brain is one vast, interconnected network, so how much you glom together and call a memory—“Well, it’s not a question that’s meaningful at the level of the brain.”

Source of Information : Scientific American Magazine

Of Flash Mobs and Four Loko

Written by Science Knowledge on 9:21 PM

An out-of-context experience can feel more intense

On an ordinary afternoon at Copenhagen Central Station, a performer sets up a drum in the center of a large hall. A cellist joins him. A woman approaches with her flute. They strike up a melody that seems familiar. A clarinet and bassoon and other instruments start playing. People pull out their cell phones and record video. Within minutes an entire symphony orchestra has assembled in the middle of the station, and suddenly it’s clear that this isn’t just your typical street performance; it’s the Copenhagen Philharmonic, and the tune is Ravel’s Boléro. This musical flash mob is a very different experience from watching an orchestra perform in a music hall, perhaps because of the novelty of the surroundings.

The same sort of disconnect may explain the peculiar potency of Four Loko, a fruit-flavored, caffeinated, alcoholic drink that was invented by three Ohio State University students in 2005. Following a series of reported hospitalizations, in 2010 the Food and Drug Administration declared that it was illegal to add caffeine to alcoholic beverages, and the makers of Four Loko complied. Case closed? That caffeinated alcoholic drinks are dangerous is clear, but is caffeine the culprit? Shepard Siegel, a psychologist at McMaster University in Ontario writing in a recent issue of Perspectives on Psychological Science, doesn’t think so.

For one thing, caffeine doesn’t seem to affect the way that alcohol gets absorbed by the body. Moreover, many drugs, including alcohol, are known to be more potent if they are taken in an unusual context. In a 1976 paper in Science, Siegel termed this the “situational specificity of tolerance.” Environmental variables ranging from the room where a drug is administered to flavor cues can influence an individual’s drug-related tolerance. What this comes down to is classical Pavlovian conditioning. The body of a social drinker learns to prepare for the alcohol in response to the environment, before the alcohol is even ingested. Siegel’s argument is that people became especially
drunk after drinking Four Loko because of the unexpected way in which it was presented: it doesn’t actually taste like alcohol. If Siegel is right, the decaf approach that the manufacturer of Four Loko has now taken could be troubling. It has announced a new beverage that comes with “a brand new flavor profile every four months.” This doesn’t fix the problem. Once someone becomes tolerant to the effects of the alcohol in one flavor, his or her tolerance would be eliminated when the next one is released. Intentional or not, Four Loko takes advantage of the situational specificity of tolerance. It has more in common with the Copenhagen Philharmonic flash mob than with your morning cuppa joe.

Source of Information : Scientific American Magazine

3-D, Hold the Glasses

Written by Science Knowledge on 9:14 PM

A breakthrough may lead to more widespread adoption of 3-D TVs

Three-dimensional television got a major marketing push nearly two years ago from the consumer electronics and entertainment industries, yet the technology has one major limitation: viewers need special eyeglasses to experience the 3-D effect. Now the marketing experts say that the technology will never catch on in a big way unless viewers can toss the glasses entirely.

Although 3-D technology sans specs is available for small screens on smartphones and portable gaming devices, these devices use backlit LCDs, which can be a big battery drain and limits how small the gadgets can be made. More recently, researchers have begun to use light-emitting diodes, which show more promise. They are developing autostereoscopic 3-D using tiny prisms that would render 3-D images without glasses. Because these LEDs get their lighting from organic compounds that glow in response to electric current, they can be thinner, lighter and more flexible than LCDs. The innovation is detailed in the August issue of the journal Nature Communications.

The researchers—from Seoul National University, Act Company and Minuta Technology—used an array of microscale prisms placed on a screen to create a filter that guides the light in one direction or another. Using such a prism array— which the researchers refer to as a Lucius prism after the Latin name meaning “shining and bright”—they were able to display an object on the screen that could be seen only when viewed from a particular angle.

By manipulating the intensity of light, the scientists could show from the same screen two distinctly different images— one to a viewer’s left eye and a second to the right eye. Seeing the two images together creates a sense of depth that the brain perceives as 3-D—all without the help of special lenses.

Some researchers have reported success with other approaches to glasses-free 3-D. The HTC EVO 3D and LG Optimus 3D smartphones, for example, feature parallax barrier screens made with precision slits that allow each eye to see a different set of pixels. Unfortunately, this approach requires the viewer to look at the screen at a very specific angle to experience the 3-D effect, a drawback that this new technique may be able to overcome.

Source of Information : Scientific American Magazine

Halting Hurricanes

Written by Science Knowledge on 9:08 PM

Tropical cyclones are nature’s most powerful storms. Can they be stopped?

As another active hurricane season in the Atlantic winds down, some atmospheric scientists say they have the tools to stop or slow the powerful storms. Their efforts, however, are hampered by a lack of funding and tricky legal issues. Until recently, the U.S. Department of Homeland Security has been investigating whether seeding storm clouds with pollution-size aerosols (particles suspended in gas) might help slow tropical cyclones.

Computer models suggest that deploying aerosols can have “an appreciable impact on tropical cyclone intensity,” writes William Cotton, an atmospheric scientist at Colorado State University. He and his colleagues recently reviewed such work in the Journal of Weather Modification. In fact, human pollution may already be weakening storms, including August’s Hurricane Irene. “[Computer] models all predicted that the intensity of Irene would be much greater than it was,” Cotton notes. “Was that because they did not include aerosol effects?” Other would-be storm stoppers, including Microsoft billionaire Bill Gates, have focused on feeding cold water to the hot storms to slow their
momentum. The Gates-backed plan proposes using a fleet of wave-powered rafts to spread a slick of colder ocean water pumped up from the depths in the path of an onrushing storm. The trouble with that process is that it could prove unwieldy. It would require hundreds of devices, and because storms are so difficult to track, placing them would be a challenge. The proof of concept will soon get a test of sorts in Hawaii. The U.S. Navy plans to deploy a prototype device that extracts energy from the temperature difference between surface and deep-ocean water. The device will involve pumping cool water to the ocean surface, in much the same manner as would be required to stop a typhoon. Would dispelling storms with cold water be a good idea? Tropical cyclones, for all their destructive force, are one of the planet’s ways of redistributing heat from the tropics to the poles. Shutting that down might have unforeseen consequences, and shifting a storm’s course could spawn punitive action from people in the new path, as a team of engineers, public policy experts and atmospheric scientists wrote in Environmental Science and Technology in April.

Regardless, for all their power, tropical cyclones are sensitive. To exploit that sensitivity, scientists would need accurate information on a storm’s future course, says meteorologist
Ross Hoffman of Atmospheric and Environmental Research. But the U.S. government is cutting funding for the satellites that make such tracking and prediction possible. For now flood maps and evacuation plans remain our best protection.

Source of Information : Scientific American Magazine


About Me

In its broadest sense, science (from the Latin scientia, meaning "knowledge") refers to any systematic knowledge or practice. In its more usual restricted sense, science refers to a system of acquiring knowledge based on scientific method, as well as to the organized body of knowledge gained through such research.

Fields of science are commonly classified along two major lines: natural sciences, which study natural phenomena (including biological life), and social sciences, which study human behavior and societies. These groupings are empirical sciences, which means the knowledge must be based on observable phenomena and capable of being experimented for its validity by other researchers working under the same conditions.


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