Wednesday, October 21, 2020

In May, a study conducted by Massachusetts Institute of Technology professor Dr Sara Seager and other researchers showed single-celled organisms like Escherichia coli and yeast can thrive in both 100% hydrogen gas and helium atmospheres. Wikinews discussed the findings with Dr Seager to know more about her research.

Life has not been observed to habitat other than Earth which has oxygen-rich environment. While Earth’s atmosphere is dominated by nitrogen-gas, oxygen is essential for most of the living organisms. There are few species of microorganisms which do not require oxygen for metabolism, referred as anærobic organisms. However, many anærobics rely on methane or nitrogen in order to thrive. Methane and nitrogen are not nearly as abundant as hydrogen and helium in the universe. Detection and study of exoplanets with hydrogen or helium atmosphere is easier as compared to nitrogen or carbon dioxide-rich atmosphere.

Researchers used Escherichia coli strain K-12 and Saccharomyces cerevisiæ strain S288C for this experiment.The two microorganisms were kept in four different environments: one being 100% air, and other three being anærobic environments: 100% H₂, 100% He, and 80%-20% N₂-CO₂. The environments were kept in at 28°Celsius. The researchers made sure experiment environment was anoxic, and had installed oxygen sensors to report fluctuation in the oxygen level. They monitored growth of E. coli using optical density measurement, and they used hæmocytometer for yeast.

The study reported the organisms were reproducing normally in both 100% H₂ and 100% He environment. However, the sigmoid-shaped growth curve was not on par with 100% air. That was because E. coli and yeast switch from ærobic respiration, which uses oxygen, to anærobic respiration and fermentation respectively. Both the processes are less efficient and do not produce enough energy.

E. coli in 80%-20% N₂-CO₂ environment had slower growth rate as CO₂ dissolves and makes the liquid medium acidic. Such reduction in growth rate was not observed for yeast cultures as yeast can thrive in acidic environments. However, yeast’s growth rate in 100% air was far greater than the other three medium. The reason of this significant difference was lack of oxygen, the research reported. Oxygen is essential for synthesis of biochemicals such as heme and sterols, which are important for yeast. In atmospheres lacking oxygen to produce these chemicals, yeast fungi has stunted growth rate.

With this discovery, Dr Seager said scientists can now observe even more planets to study for habitable life.

“There’s a diversity of habitable worlds out there, and we have confirmed that Earth-based life can survive in hydrogen-rich atmospheres […] We should definitely add those kinds of planets to the menu of options when thinking of life on other worlds, and actually trying to find it”, Professor Seager said.

A rocky planet with expanded hydrogen-rich atmosphere is easy to detect using the current technologies. Hydrogen and helium gas have very low density. Dr Seager said “It’s kind of hard to get your head around, but that light gas just makes the atmosphere more expansive […] And for telescopes, the bigger the atmosphere is compared to the backdrop of a planet’s star, the easier it is to detect.”

The research paper highlighted rocky planets which have radius no more than 1.7 times Earth’s radius (Earth’s radius is roughly 6360 km) can produce hydrogen-rich atmosphere, if water were to react with Iron.

The research paper reported E. coli releases a number of gases when it lives in hydrogen-based atmosphere including ammonia, methanethiol, dimethylsulfide, carbonyl sulfide, carbonyl disulfide and nitrous oxide. These gases can serve as biosignature gases which can help astronomers detect and study planets for potential life on exoplanets.

Confirming life can thrive in atmospheres which does not have oxygen, Seager said “Astronomers should keep an open mind as to which planets are worth searching for life”.

Seager said she was happy after confirming the result as she was anticipating the outcome.

With NASA’s James Webb Telescope scheduled to be deployed next year, researchers could observe smaller exoplanets which orbit small red-dwarf planets.

[edit]

Monday, December 3, 2007

At Thanksgiving dinner David Shankbone told his white middle class family that he was to interview Reverend Al Sharpton that Saturday. The announcement caused an impassioned discussion about the civil rights leader’s work, the problems facing the black community and whether Sharpton helps or hurts his cause. Opinion was divided. “He’s an opportunist.” “He only stirs things up.” “Why do I always see his face when there’s a problem?”

Shankbone went to the National Action Network’s headquarters in Harlem with this Thanksgiving discussion to inform the conversation. Below is his interview with Al Sharpton on everything from Tawana Brawley, his purported feud with Barack Obama, criticism by influential African Americans such as Clarence Page, his experience running for President, to how he never expected he would see fifty (he is now 53). “People would say to me, ‘Now that I hear you, even if I disagree with you I don’t think you’re as bad as I thought,'” said Sharpton. “I would say, ‘Let me ask you a question: what was “bad as you thought”?’ And they couldn’t say. They don’t know why they think you’re bad, they just know you’re supposed to be bad because the right wing tells them you’re bad.”

Thursday, January 29, 2009

Giving a cow a name and treating her as an individual with “more personal touch” can increase milk production, so says a scientific research published in the online “Anthrozoos,” which is described as a “multidisciplinary journal of the interactions of people and animals”.

The Newcastle University‘s School of Agriculture, Food and Rural Development’s (of the Newcastle University Faculty of Science, Agriculture and Engineering) researchers have found that farmers who named their dairy cattle Ermintrude, Daisy, La vache qui rit, Buttercup, Betsy, or Gertrude, improved their overall milk yield by almost 500 pints (284 liters) annually. It means therefore, an average-sized dairy farm’s production increases by an extra 6,800 gallons a year.

“Just as people respond better to the personal touch, cows also feel happier and more relaxed if they are given a bit more one-to-one attention,” said Dr Catherine Douglas, lead researcher of the university’s School of Agriculture, Food and Rural Development. “By placing more importance on the individual, such as calling a cow by her name or interacting with the animal more as it grows up, we can not only improve the animal’s welfare and her perception of humans, but also increase milk production,” she added.

Drs Douglas and Peter Rowlinson have submitted the paper’s conclusion: “What our study shows is what many good, caring farmers have long since believed. Our data suggests that, on the whole, UK dairy farmers regard their cows as intelligent beings capable of experiencing a range of emotions.” The scientific paper also finds that “if cows are slightly fearful of humans, they could produce [the hormone] cortisol, which suppresses milk production,” Douglas noted. “Farmers who have named their cows, probably have a better relationship with them. They’re less fearful, more relaxed and less stressed, so that could have an effect on milk yield,” she added.

South Norfolk goldtop-milk producer Su Mahon, one of the country’s top breeder of Jersey dairy herds, agreed with Newcastle’s findings. “We treat all our cows like one of the family and maybe that’s why we produce more milk,” said Mrs Mahon. “The Jersey has got a mind of its own and is very intelligent. We had a cow called Florence who opened all the gates and we had to get the welder to put catches on to stop her. One of our customers asked me the other day: ‘Do your cows really know their names?’ I said: I really haven’t a clue. We always call them by their names – Florence or whatever. But whether they really do, goodness knows,” she added.

The researchers’ comparative study of production from the country’s National Milk Records reveals that “dairy farmers who reported calling their cows by name got 2,105 gallons (7,938 liters) out of their cows, compared with 2,029 gallons (7,680 liters) per 10-month lactation cycle, and regardless of the farm size or how much the cows were fed. (Some 46 percent of the farmers named their cows.)”

The Newcastle University team which has interviewed 516 UK dairy farmers, has discovered that almost half – 48% – called the cows by name, thereby cutting stress levels and reported a higher milk yield, than the 54% that did not give their cattle names and treated as just one of a herd. The study also reveals cows were made more docile while being milked.

“We love our cows here at Eachwick, and every one of them has a name,” said Dennis Gibb, with his brother Richard who co-owns Eachwick Red House Farm outside of Newcastle. “Collectively, we refer to them as ‘our ladies,’ but we know every one of them and each one has her own personality. They aren’t just our livelihood, they’re part of the family,” Gibb explained.

“My brother-in-law Bobby milks the cows and nearly all of them have their own name, which is quite something when there are about 200 of them. He would be quite happy to talk about every one of them. I think this research is great but I am not at all surprised by it. When you are working with cows on a daily basis you do get to know them individually and give then names.” Jackie Maxwell noted. Jackie and her husband Neill jointly operate the award-winning Doddington Dairy at Wooler, Doddington, Northumberland, which makes organic ice cream and cheeses with milk from its own Friesian cows.

But Marcia Endres, a University of Minnesota associate professor of dairy science, has criticized the Newcastle finding. “Individual care is important and could make a difference in health and productivity. But I would not necessarily say that just giving cows a name would be a foolproof indicator of better care,” she noted. According to a 2007 The Scientist article, named or otherwise, dairy cattle make six times more milk today than they did in the 1990s. “One reason is growth hormone that many U.S. farmers now inject their cows with to increase their milk output; another is milking practices that extend farther into cows’ pregnancies, according to the article; selective breeding also makes for lots of lactation,” it states.

Critics claimed the research was flawed and confused a correlation with causation. “Basically they asked farmers how to get more milk and whatever half the farmers said was the conclusion,” said Hank Campbell, author of Scientific Blogging. In 1996, the Department for Environment, Food and Rural Affairs provided for a complex new cattle passport system where farmers were issued with passport identities. The first calf born under the new regime were given names like “UK121216100001.”

Dr Douglas, however, counters that England doesn’t permit dairy cattle to be injected hormones. The European Union and Canada have banned recombinant bovine growth hormone (rGBH), which increases mastitis infection, requiring antibiotics treatment of infected animals. According to the Center for Food Safety, rGBH-treated cows also have higher levels of the hormone insulin-like growth factor 1 (IGF1), which may be associated with cancer.

In August 2008, Live Science published a study which revealed that cows have strange sixth sense of magnetic direction and are not as prone to cow-tipping. It cited a study of Google Earth satellite images which shows that “herds of cattle tend to face in the north-south direction of Earth’s magnetic lines while grazing or resting.”

Newcastle University is a research intensive university in Newcastle upon Tyne in the north-east of England. It was established as a School of Medicine and Surgery in 1834 and became the “University of Newcastle upon Tyne” by an Act of Parliament in August 1963.

The School of Agriculture, Food and Rural Development is a school of the Newcastle University Faculty of Science, Agriculture and Engineering, a faculty of Newcastle University. It was established in the city of Newcastle upon Tyne as the College of Physical Science in 1871 for the teaching of physical sciences, and was part of Durham University. It existed until 1937 when it joined the College of Medicine to form King’s College, Durham.