Culture
Spatial isolation is known to promote speciation - but researchers at Ludwig-Maximilians-Universitaet (LMU) in Munich have now shown that, at least in yeast, the opposite is also true. New ecological variants can also evolve within thoroughly mixed populations.
WHAT:
Salmonella enterica serovar Typhimurium bacteria (S. Typhimurium) commonly cause human gastroenteritis, inflammation of the lining of the intestines. The bacteria live inside the gut and can infect the epithelial cells that line its surface. Many studies have shown that Salmonella use a "run-and-tumble" method of short swimming periods (runs) punctuated by tumbles when they randomly change direction, but how they move within the gut is not well understood.
As anxious passengers are often reassured, commercial aircrafts can easily continue to fly even if one of the engines stops working. But for drones with four propellers - also known as quadcopters - the failure of one motor is a bigger problem. With only three rotors working, the drone loses stability and inevitably crashes unless an emergency control strategy sets in.
A recent Point of Reference article, "The meat of the matter: Environmental dissemination of beef cattle agrochemicals," published in Environmental Toxicology and Chemistry, points at synthetic chemical cocktails being emitted from cattle feed yards into the environment and how they can impact our ecosystem and our health.
Our immune system is never idle. Their task is to detect and eliminate invasive pathogens, and they have no time to lose. The adaptive immune system identifies infectious organisms by recognizing foreign proteins on the surfaces of bacteria, viruses and unicellular protozoans. The interaction of these antigens with immune cells triggers a series of downstream events, which in most cases leads to the elimination of the pathogen.
(Philadelphia, PA) - Like a failing fuel pump that causes a loss of engine power in a car, a diseased heart can take a serious toll on the body's performance. For some patients, tasks like walking up a flight of stairs or walking across a room eventually turn into exhausting endeavors. This is because, over time, regardless of the underlying cause, heart damage typically progresses, owing to a constant barrage of oxidative stress and toxic lipids that alter heart cell energetics and, ultimately, the ability of the heart to function normally.
A team of researchers led by the University of California, Berkeley and the University of Michigan has discovered an antibody that blocks the spread within the body of the dengue virus, a mosquito-borne pathogen that infects between 50 and 100 million people a year. The virus causes what is known as dengue fever, symptoms of which include fever, vomiting and muscle aches, and can lead to more serious illnesses, and even death.
The fascinating compound eyes of insects consist of hundreds of individual eyes known as "facets". In the course of evolution, an enormous variety of eye sizes and shapes has emerged, often representing adaptations to different environmental conditions. Scientists, led by an Emmy Noether research group at the University of Göttingen, together with scientists from the Andalusian Centre for Developmental Biology (CABD) in Seville, have now shown that these differences can be caused by very different changes in the genome of fruit flies.
Egg cells are among the largest cells in the animal kingdom. If moved only by the random jostlings of water molecules, a protein could take hours or even days to drift from one side of a forming egg cell to the other. Luckily, nature has developed a faster way: cell-spanning whirlpools in the immature egg cells of animals such as mice, zebrafish and fruit flies. These vortices enable cross-cell commutes that take just a fraction of the time. But until now, scientists didn't know how these crucial flows formed.
(Boston)--What percent of patients with Alzheimer's Disease (AD) currently have severe dementia? Do more people have mild disease? Or are the majority suffering with moderate dementia? A new study using data from the Framingham Heart Study (FHS) sheds light on these trends.
In 2007, an increase in world food prices led to a global rush for land in the form of land grabs or large-scale land acquisitions. Over the last two decades, such acquisitions have resulted in millions of hectares of land changing hands in developing nations. Although such changeover can increase the cultivation of crops needed to feed the world's growing population and spark new agricultural practices and technologies, it can also lead to environmental degradation, increased carbon emissions and threats to the livelihoods of smallholder farmers.
Financial responsibility means managing money in a relatively sensible way by minimizing superfluous or unnecessary spending. But according to new research from the University of Notre Dame, people think they are more financially responsible than they actually are.
New probes allow scientists to see four-stranded DNA interacting with molecules inside living human cells, unravelling its role in cellular processes.
DNA usually forms the classic double helix shape of two strands wound around each other. While DNA can form some more exotic shapes in test tubes, few are seen in real living cells.
As marijuana outlets open after the drug is legalized, the density of those recreational retailers is associated with more use and a greater intensity of use among young adults, according to a new RAND Corporation study.
The study is among the first to examine associations between the density of marijuana outlets and marijuana use over time, and is the first to include unlicensed dispensaries in such an analysis.