Heat engines transform heat into mechanical energy with the corresponding efficiency of an Otto engine amounting to only about 25 percent, which is what your automobile gets.

The efficiency of heat engines powered by thermal heat reservoirs is determined by the second law of thermodynamics, one of the fundamental concepts in physics. It was as far back as 1824 that Frenchman Nicolas Carnot calculated the maximum possible efficiency limit of such engines, now known as the Carnot limit.

Agriculture in Finland is becoming more market driven.

What will that mean? Fluctuation in prices, more so than with current EU and Finland subsidies and quotas, but better efficiency. Competition will mean fewer farms.  The reason for the changes is because profitability continues to be poor despite strong spending by the government. The return on investment for taxpayer spending has been negative on average for the last 10 years. In 2011 in Finland, it was the third weakest in the EU, at -1.1 per cent.  The brunt of that inefficiency is small farms kept going only because of subsidies. Half of the farms in Finland produce only 5 percent of the food.

It looks more like a painting than a real-life event but this image from the Cassini orbiter shows the progress of a massive storm on Saturn. 

The head of the storm is towards the left of the image, where the most turbulent activity is shown in white, but towards the center you can also see the trace of a spinning vortex in the wake of the storm.

The image is centered at about 0º longitude and 35º N latitude and has had its colors enhanced to help reveal the complex processes in Saturn’s weather. The white corresponds to the highest cloud tops, but to the human eye the storm would appear more as a bright area against a yellow background.

Survey results analyzed by psychologists at The Fenway Institute, an advocacy group for the lesbian, gay, bisexual, and transgender (LGBT) community, found that gay and bisexual boys use anabolic-androgenic steroids (AAS) at rates much higher than their straight counterparts - almost 6X higher.

Compact fluorescent bulbs save energy but they also contain mercury, a toxic metal.

While environmentalists have promoted them as safe, and the US government has given them a de factor mandate and subsidy by banning incandescent bulbs, there are still concerns among the public about the risks of having hazardous materials in their homes.

Mercury lamps, on the other hand, have been around since 1860. They were rarely used in the home, they are a big part of the reason why incandescent bulbs were invented in the first place, because they made human skin look 'green' and the risks in an enclosed space were too high but are more common in street lamps, because they have long life.

Babies delivered at home by midwives had a roughly four times higher risk of neonatal deaths than babies delivered in hospitals, also by midwives. 

The paper is not out to indict the midwife delivery fad but suggests they aren't going to be qualified to deal with problems the way a hospital setting and doctors would be.
The authors link the increased neonatal mortality risk with the location of a planned birth, rather than the credentials of the person delivering the baby. 

Though you may have read otherwise, numerous studies from China, Spain and the United States have have found that the biodiversity of insects and related arthropods is not reduced by genetically modified (GM) rice, cotton, or maize fields.

A new study from South Africa published in Environmental Entomology shows similar results, that biodiversity is the same as that among conventional crops.

A total of 8,771 arthropod individuals, comprising 288 morphospecies, were collected from 480 plants sampled from Bt maize and non-Bt maize fields over a two-year period. The researchers found no significant differences in abundance or diversity in detritivores, herbivores, predators, or parasitoids.

I used to have the “meta” itch, but I learned to live with it and stop scratching it. It only irritates anyway, without doing much good work.

Let me explain.

If you are a regular (or even occasional) reader of Rationally Speaking you know that we often publish essays that have to do with ethics and moral philosophy. That's because ethics is one of those things that always lurks in the background (and sometimes the foreground) of our lives, whether we reflect on it or not. And I of course think it is better to reflect on it, at least from time to time.

Middle-aged women the world over are now...chuckling.

At least I imagine they are, given the news this week that testosterone supplementation may increase the risk of heart disease.

If you already have heart disease.

Or if you’re over 65.

Five Empa laboratories were involved in the EU «NanoHouse» project, along with four other European research institutes and four industrial partners. The aim of the project was to investigate the opportunities and risks presented by the nanomaterials used in the surface coatings applied to building façades. For the first time not only were freshly manufactured products studied to see if they set free nanoparticles, but also aged samples.