Biomass is one of the main sources of energy and heat in the field of renewable energy production: it is any type of non-fossil organic matter, such as living plants, timber, agricultural and livestock waste, wastewater, solid urban organic waste, etc. The three most developed technologies for obtaining energy from biomass are as follows: pyrolysis (decomposition by heating in the absence of oxygen), gasification (reaction with air, oxygen or a blend of both and conversion into gas) and combustion (decomposition through heating with oxygen). The effectiveness and emission levels of these three processes change depending on the composition of the biomass as well as its properties, the experimental conditions and equipment used.

Jessica Alba's "Honest" company has been criticized for being frauds but it's not alone. Though the variation in cost for sunscreen protection averages well over 3,000, the variation is protection is not very much.

Like with organic food, you don't get what you pay for - unless what you are paying for is self-identification. But no matter what you pay or why you buy, you may not be getting a product that meets the American Academy of Dermatology's guidelines for sunscreens. This was largely due to a lack of water or sweat resistance, according to a new Northwestern Medicine study.

Beer is the world's most commonly fermented beverage and lager beer commands 94 percent of the global market. Making the beer possible is a biological oddity: a hybrid yeast that combines two distinct species and confers the ability to make cold-brewed beer, a product that first emerged 500 years ago in Europe.

 Without question, the domesticated hybrid yeast that gives us lager beer is an organism worth many billions of dollars, but just how Saccharomyces cerevisiae, the well-known domesticated yeast that gives us wine and bread, combined with Saccharomyces eubayanus, a yeast species only recently discovered in nature, to give us the hybrid organism that makes cold-brewed beer remains a mystery.

Moral judgments, ideas about good or bad, remain the building block of cooperation in a large group.

A rule of thumb for promoting cooperation is to help those who have a good reputation and not those who have a bad reputation, yet that determination requires time, effort and money. What about moral "free riders" who evade the cost associated with moral judgment (e.g. by not paying taxes for police and court) so are better off than those who shoulder the cost?

Philosophers debate voluntary reactive policing of the moral free riders, which is costly, too, and thus can be exploited by higher order moral free riders. This leads to an infinite regression of opportunities to free ride.

Can the moral free rider problem really be solved? 

It is time for NHS England to "do the right thing" and fund pre-exposure prophylaxis (PrEP) for HIV prevention, argue two senior public health doctors in The BMJ today.

Directors of public health Jim McManus and Dominic Harrison, say despite overwhelming evidence that PrEP against HIV infection is largely safe, effective, and cost effective, NHS England has declined to make it available on the NHS, arguing that HIV prevention is the responsibility of local government.

Such an approach, they write, "confounds its advocacy of a health and care system integrated around the best outcomes for the citizen and perpetuates an incoherent national approach to HIV prevention."

Current federal agricultural subsidies focus on financing production of food commodities, a large portion of which are converted into high-fat meat and dairy products, refined grains, high-calorie juices and soft drinks (sweetened with corn sweeteners), and processed and packaged foods.

Karen R. Siegel, Ph.D., of the Centers for Disease Control and Prevention, Atlanta, and coauthors used data from the National Health and Nutrition Examination Survey from 2001 to 2006 to calculate an individual-level "subsidy score" for consumption of subsidized food commodities as a percentage of total calorie intake.

The study, which relied on a single day of 24-hour dietary recall, included 10,308 participants, about half of whom were men, with an average age of about 40.