N Nitrogen

Some 3.2 million Americans have chronic hepatitis C , an infection that can linger in the body for years before producing symptoms. It can eventually lead to serious liver scarring and cancer. And most infections in the U.S. are the disease's particularly tough breed, known as genotype 1, which has a cure rate of less than 40 percent with the best current treatment. [More]

Dear EarthTalk : I understand a recent government report concluded that our global food system is in deep trouble, that roughly two billion people are hungry or undernourished while another billion are overconsuming to the point of obesity. What’s going on? -- Ellie Francoeur, Baton Rouge, La.

The report in question, “The Future of Food and Farming”, synthesized findings collected from more than 400 scientists spanning 34 countries and was published in January 2011 by the British government’s Department for Business Innovation & Skills. Its troubling bottom-line conclusion is that the world’s existing food system is failing half of the people on the planet.

In early summer 2008 Timothy Walsh of Cardiff University in Wales got an e-mail from Christian Giske, an acquaintance who is a physician on the faculty of Sweden’s Karolinska Institute. Giske had been treating a 59-year-old man hospitalized that past January in Örebro, a small city about 100 miles from Stockholm. The man had lived with diabetes for many years, suffered several strokes and had lately developed deep bedsores. But those were not the subject of Giske’s message. Instead he was worried about a bacterium that a routine culture had unexpectedly revealed in the man’s urine. Would Walsh, who runs a lab that unravels the genetics of antibacterial resistance, be willing to take a look at the bug?

Walsh agreed and put the isolate through more than a dozen assays. It was Klebsiella pneumoniae , a bacterium that in hospitalized patients is one of the most frequent causes of pneumonia and bloodstream infection. This strain, though, contained something new, a gene that Walsh had never seen before. It rendered the Klebsiella , which was already resistant to many antibiotics used in critical care medicine, insensitive to the only remaining group that worked reliably and safely--the carbapenems, the so-called drugs of last resort. The one medication the investigators found that had any effect on the resistant strain was colistin, a drug that had been out of general use for years because of its toxic effects on the kidneys. Walsh named the enzyme that this gene produced New Delhi metallo-beta-lactamase, or NDM-1, for the city where the man acquired the infection just before he returned home to Sweden.

Think about the last time you got bored with the TV channel you were watching and decided to change it with the remote control. Or a time you grabbed a magazine off a newsstand, or raised a hand to hail a taxi. As we go about our daily lives, we constantly make choices to act in certain ways. We all believe we exercise free will in such actions – we decide what to do and when to do it. Free will, however, becomes more complicated when you try to think how it can arise from brain activity.

Do we control our neurons or do they control us? If everything we do starts in the brain, what kind of neural activity would reflect free choice? And how would you feel about your free will if we were to tell you that neuroscientists can look at your brain activity, and tell that you are about to make a decision to move – and that they could do this a whole second and a half before you yourself became aware of your own choice?

In early summer 2008 Timothy Walsh of Cardiff University in Wales got an e-mail from Christian Giske, an acquaintance who is a physician on the faculty of Sweden’s Karolinska Institute. Giske had been treating a 59-year-old man hospitalized that past January in Örebro, a small city about 100 miles from Stockholm. The man had lived with diabetes for many years, suffered several strokes and had lately developed deep bedsores. But those were not the subject of Giske’s message. Instead he was worried about a bacterium that a routine culture had unexpectedly revealed in the man’s urine. Would Walsh, who runs a lab that unravels the genetics of antibacterial resistance, be willing to take a look at the bug?

Walsh agreed and put the isolate through more than a dozen assays. It was Klebsiella pneumoniae , a bacterium that in hospitalized patients is one of the most frequent causes of pneumonia and bloodstream infection. This strain, though, contained something new, a gene that Walsh had never seen before. It rendered the Klebsiella , which was already resistant to many antibiotics used in critical care medicine, insensitive to the only remaining group that worked reliably and safely--the carbapenems, the so-called drugs of last resort. The one medication the investigators found that had any effect on the resistant strain was colistin, a drug that had been out of general use for years because of its toxic effects on the kidneys. Walsh named the enzyme that this gene produced New Delhi metallo-beta-lactamase, or NDM-1, for the city where the man acquired the infection just before he returned home to Sweden.

By 2020, 15 million people worldwide will have cancer and nine million of them will be living in developing countries, according to World Health Organization estimates. Harvard University physician and medical anthropologist Paul Farmer is determined to ensure that prediction doesn’t come true. Farmer, a pioneer in global health, has a history of tackling big problems. His Ph.D. dissertation on HIV in Haiti ran to 1,000 pages, leading Harvard to impose a cap. Since then, as co-founder of the nonprofit Partners In Health, he has brought medical treatments, from basic primary care to antiretroviral therapies for AIDS, to millions of the world’s poor.

Farmer’s work--chronicled in the Tracy Kidder best seller Mountains beyond Mountains and in his own books--has inspired governments and global agencies to do likewise. Recently he has focused his attention on cancer in the developing world, where the disease is increasingly common and costly treatments are often hard to come by. In the medical journal the Lancet last October, he and a team of other leaders from the Global Task Force on Expanded Access to Cancer Care and Control in Developing Countries announced an ambitious, multipronged plan to increase these countries’ access to cancer medical resources--by raising money, driving down the cost of drugs, and figuring out new ways to get those drugs to patients in need. Science writer Mary Carmichael spoke with Farmer at his office in Boston. Excerpts follow.

Think you would stick to a diet if someone paid you for it? Would you be more likely to exercise if you were fined each time you bailed on your scheduled workout?

Research in recent years suggests--and a handful of new businesses are betting--that you might. The Web-based company StickK.com lets users sign commitment contracts to lose weight, exercise or quit smoking--and pay up if they default. Members of the Boston-based start-up Gym-Pact are charged for every day they pledge to work out but do not.

The African nation of Rwanda recently set a goal of circumcising an estimated two million adult men by the end of 2012 to fight the spread of HIV, and is investigating a new nonsurgical device that is said to allow practitioners to perform the procedure in less than four minutes--without anesthesia.

The patent pending PrePex device includes an elastic mechanism that fits around an inner ring, trapping the penis foreskin--the loose fold of skin that covers its glans--which cuts its blood supply. The foreskin thereby dries up and can be safely removed after a week. Neither anesthetics nor sterile settings nor sutures are required--and no blood is lost. After the procedure the Rwandan government guidelines suggest that patients abstain from having sex for six weeks, which is also the case after conventional surgery. This device, it is hoped, could help scale up Rwanda's mass circumcision initiative.

The developing crisis at the Fukushima Daiichi nuclear power plant in the wake of the March 11 earthquake and tsunami has raised concerns over the health effects of radiation exposure: What is a "dangerous" level of radiation? How does radiation damage health? What are the consequences of acute and long-term low-dose radiation? [More]

Consider this a warning: the theory I’m about to describe is likely to boil untold liters of blood and prompt mountains of angry fists to clench in revolt. It’s the best--the kindest--of you out there likely to get the most upset, too. I’d like to think of myself as being in that category, at least, and these are the types of visceral, illogical reactions I admittedly experienced in my initial reading of this theory. But that’s just the non-scientist in me flaring up, which, on occasion, it embarrassingly does. Otherwise, I must say upfront, the theory makes a considerable deal of sense to me.

The work in question dates back to 1995-1996 and involves a four-paper exchange published in Ethology and Sociobiology . It is a dialogue between two influential evolutionary psychologists-- Gordon Gallup of SUNY-Albany, whose work on human sexuality I’ve covered before, and British psychologist John Archer of the University of Central Lancashire. Their primary debate is about whether or not people’s aversion to homosexuality (colloquially called "homophobia," although both authors acknowledge that this is a misnomer because it is more a negative attitude towards this demographic than it is fear) is a product of natural selection or, alternatively, a culturally constructed, transmitted bias. That this discussion ended in 1996, and not a single study to my knowledge has sought to disentangle the various knots in both scientists’ positions, is revealing in its own right, and probably reflective of shifts in the social zeitgeist since then.