There's a satellite in medium Earth orbit - one of 31 U.S. Air Force satellites - that carries some special cargo; a collection of sensors to detect and triangulate airborne or space-based nuclear explosions anywhere they may occur.

In the recent past, detection has been no problem — there haven’t been any above-ground explosions for decades - but there could be one any time and the country that did it could simply deny if its leaders didn’t believe anyone could track it.

These sensors have to be ready to detect a real explosion and also to compensate for false alarms: There are lightning bolts that occur more than once per second, energetic particles from the Van Allen radiation belt that collide with electronics on the satellite, a welter of “noise” from cell phone communications, and meteors.

Sideria Hendricks is only 10 years old, but she already has suffered two strokes.

The first occurred on Christmas Eve a few years ago. Sideria suddenly couldn't speak, and her left arm and left leg went limp. She eventually recovered, but later suffered a second minor stroke.

About 3,200 strokes occur each year in children under age 18. Although strokes are among the top ten causes of death in childhood, family members and doctors often are slow to recognize symptoms, said Dr. Jose Biller, a co-author of the American Heart Association's new guidelines for managing strokes in children.

Why do humans cooperate in things as diverse as environment conservation or the creation of fairer societies, even when they don’t receive anything in exchange or, worst, they might even be penalized? This is a question that has puzzled academics for centuries, especially since in evolution the basis for the “survival of the fittest” is, after all, selfishness.

But in an article just published in the journal Nature, three Portuguese theoretical physicists developed a mathematical model capable of providing a way out from this conundrum through the introduction of social diversity - a ubiquitous characteristic of modern social networks - and suggesting that that the act of cooperation may depend on one’s social context/ranking. And in fact, when social diversity was taken into account the numbers of those cooperating increased in direct relation to the system diversity.

Living on a desert island may not even be a mode of escape from Lyme disease because birds can also be a carrier of infected ticks. Dorothy Leland, who is an advocate with the California Lyme Disease Association and has a daughter with the disease used to love the outdoors a lot more. Since her daughter contracted Lyme over three years ago Leland has taken a different perspective on life in the great outdoors.

Ticks that carry the Lyme disease infection, which causes a rash that looks similar to Saturn rings, is a very complex disease to spot, prevent, and cure. Lyme disease associations like lymedisease.org that Leland is a part of aid in the education and prevention of Lyme. Leland says there are three main things one should remember when setting out for an expedition in nature: Be aware, choose spots carefully, and wear repellant.

At Cairo museum, on Queen Hatshepsut’s tomb in Deir el Bahari,it shows the chief Parihou with his wife Ati, Queen of Punt, (an area not still geographically established: Yemen, Somalia, Ethiopia, Eritrea, Sudan?) while they offer gifts to the Egyptian Queen Hatshepsut (1516-1481 BC).

A naval expedition to the mysterious land of Punt was undertaken in the summer of Hatshepsut’s eighth year as queen; she sent a fleet of five ships, headed by her Chancellor Senenmet. The Queen of Punt shows a rugged face, gluteal and femoral obesity, hyperlordosis and symmetrical deposits of fat on the trunk, limbs and thighs.

Research shows that as more scholarly and research journals are available online, researchers are citing fewer of them - and they are primarily newer papers.

There's no question the Internet gives scientists and researchers instant access to a wealth of academic journals, a very good thing, but the impact hadn't been studied until recently. New research in Science says that scholars are actually citing fewer papers in their work, and the papers they do cite tend to be more recent publications. This trend may be limiting the creation of new ideas and theories.

James Evans is an assistant professor of sociology at the University of Chicago, who focuses on the nature of scholarly research. During a lecture on the influence of private industry money on research, a student instead asked how the growth of the Internet has shaped science. "I didn't have an immediate answer," Evans said.

Humans have long been trying to make the dream of nanoscopic robots come true. It's getting closer each time nanoscience produces components for molecular-scale machines.

One such device is a rotor; a movable component that rotates around an axis. Trying to observe such rotational motion on the molecular scale is an extremely difficult undertaking but Japanese researchers at the Universities of Osaka and Kyoto have met this challenge. As Akira Harada and his team report in the journal Angewandte Chemie, they were able to get "snapshots" of individual molecular rotors caught in motion.

As the subject of their study the researchers chose a rotaxane. This is a two-part molecular system: A rod-shaped molecule is threaded by a second, ring-shaped molecule like a cuff while a stopper at the end of the rod prevents the ring from coming off. The researchers attached one end of the rod to a glass support. To observe the rotational motions of the cuff around the sleeve, the scientists attached a fluorescing side chain to the cuff as a probe.

Researchers from China, France, Italy, and the United Kingdom, have created a model that shows exactly how, when a baby suckles at a mother's breast, it starts a chain of events that leads to a surge of the "trust" hormone oxytocin in their mother's brain.

Research at the University of Liverpool has found how Saharan dust storms help sustain life over extensive regions of the North Atlantic Ocean.

Working aboard research vessels in the Atlantic, scientists mapped the distribution of nutrients including phosphorous and nitrogen and investigated how organisms such as phytoplankton are sustained in areas with low nutrient levels.

They found that plants are able to grow in these regions because they are able to take advantage of iron minerals in Saharan dust storms. This allows them to use organic or 'recycled' material from dead or decaying plants when nutrients such as phosphorous – an essential component of DNA – in the ocean are low.

Viruses achieve their definition of success when they can thrive without killing their host. Now, biologists Pamela Bjorkman and Zhiru Yang of the California Institute of Technology have uncovered how one such virus, prevalent in humans, evolved over time to hide from the immune system.

The human immune system and the viruses hosted by our bodies are in a continual dance for survival--viruses ever seek new ways to evade detection, and our immune system devises new methods to hunt them down. Human Cytomegalovirus (HCMV), says Bjorkman, Caltech's Delbrück Professor of Biology and a Howard Hughes Medical Institute (HHMI) Investigator, "is the definition of a successful virus--it thrives but it doesn't affect the host."