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ScienceDaily (May 27, 2011) - Ionizing radiation is not without danger to human populations. Indeed, exposure to nuclear radiation leads to an increase in male births relative to female births, according to a new study by Hagen Scherb and Kristina Voigt from the Helmholtz Zentrum München.

Future Mars outposts or colonies may seem more distant than ever with NASA's exploration plans in flux, but the rocket technology that could someday propel a human mission to the red planet in as little as 40 days may already exist. A company founded by former NASA astronaut Franklin Chang-Diaz has been developing a new rocket engine that draws upon electric power and magnetic fields to channel superheated plasma out the back. That stream of plasma generates steady, efficient thrust that uses low amounts of propellant and builds up speed over time. "People have known for a long time, even back in the '50s, that electric propulsion would be needed for serious exploration of Mars," said Tim Glover, director of development at the Ad Astra Rocket Company.

"It's a hoax," said coal company CEO Don Blankenship, "because clearly anyone that says that they know what the temperature of the Earth is going to be in 2020 or 2030 needs to be put in an asylum because they don't." On the other side of the debate was environmentalist Robert Kennedy, Jr. "Ninety-eight percent of the research climatologists in the world say that global warming is real, that its impacts are going to be catastrophic," he argued. "There are 2 percent who disagree with that. I have a choice of believing the 98 percent or the 2 percent." To social scientist and lawyer Don Braman, it's not surprising that two people can disagree so strongly over science. Braman is on the faculty at George Washington University and part of The Cultural Cognition Project, a group of scholars who study how cultural values shape public perceptions and policy

It's not quite Cyclops, the sci-fi superhero from the X-Men franchise whose eyes produce destructive blasts of light, but for the first time a laser has been created using a biological cell. The human kidney cell that was used to make the laser survived the experience. In future such "living lasers" might be created inside live animals, which could potentially allow internal tissues to be imaged in unprecedented detail. It's not the first unconventional laser. Other attempts include lasers made of Jell-O and powered by nuclear reactors (see box below). But how do you go about giving a living cell this bizarre ability? Typically, a laser consists of two mirrors on either side of a gain medium - a material whose structural properties allow it to amplify light. A source of energy such as a flash tube or electrical discharge excites the atoms in the gain medium, releasing photons. Normally, these would shoot out in random directions, as in the broad beam of a flashlight, but a laser uses mirrors on either end of the gain medium to create a directed beam. As photons bounce back and forth between the mirrors, repeatedly passing through the gain medium, they stimulate other atoms to release photons of exactly the same wavelength, phase and direction. Eventually, a concentrated single-frequency beam of light erupts through one of the mirrors as laser light.

The supply of secure, clean, sustainable energy is arguably the most important scientific and technical challenge facing humanity in the 21st century. Rising living standards of a growing world population will cause global energy consumption to double by mid-century and triple by the end of the century. Even in light of unprecedented conservation, the additional energy needed is simply not attainable from long discussed sources these include nuclear, biomass, wind, geothermal and hydroelectric. The global appetite for energy is simply too much. Petroleum-based fuel sources (i.e., coal, oil and gas) could be increased. However, deleterious consequences resulting from external drivers of economy, the environment, and global security dictate that this energy need be met by renewable and sustainable sources. The dramatic increase in global energy need is driven by 3 billion low-energy users in the non-legacy world and by 3 billion people yet to inhabit the planet over the next half century. The capture and storage of solar energy at the individual level personalized solar energy drives inextricably towards the heart of this energy challenge by addressing the triumvirate of secure, carbon neutral and plentiful energy. This talk will place the scale of the global energy issue in perspective and then discuss how personalized energy (especially for the non-legacy world) can provide a path to a solution to the global energy challenge. Daniel G. Nocera is the Henry Dreyfus Professor of Energy at the Massachusetts Institute of Technology, Director of the Solar Revolutions Project and Director of the Eni Solar Frontiers Center at MIT. His group pioneered studies of the basic mechanisms of energy conversion in biology and chemistry. He has recently accomplished a solar fuels process that captures many of the elements of photosynthesis outside of the leaf. This discovery sets the stage for a storage mechanism for the large scale, distributed, deployment of solar energy. He has b

NBC exposes the "unspeakable" realities of the Japanese catastrophe in its 60 Minutes program Sunday night during which leading nuclear scientist Dr. Michio Kaku said radiation from Fukushima will impact of all of humanity.

David Baum, University of Wisconsin, says: "All agree that eukaryotes arose from a symbiotic relationship between two cell types: bacteria that became mitochondria and a host cell, archaea, or a close relative of archaea, that became the cytoplasm and nucleus. This symbiosis explains the origin of mitochondria, but what about other eukaryotic structures, most notably the nucleus?" The Baums' inside-out theory provides a gradual path by which eukaryotic cells could have evolved. The first stage began with a bacterial cell whose outer membrane forms protrusions, which the Baums call 'blebs', that reached out from the cell. These protrusions trapped free-living mitochondria-like bacteria between them. Using the energy gained from being in close contact with bacteria (and using bacterial-derived lipids), cells were able to get bigger and expand the size of their blebs. The sides of the blebs formed the endoplasmic reticulum and their inner surfaces formed the outer membrane of the nucleus, with the original outer membrane of the archaeon becoming what we now call the inner nuclear membrane. Finally, the fusion of blebs with one another led to the formation of the plasma membrane. The result was the eukaryotic cell as we now know it. This inside-out theory is explained in more detail using a diagram in the research article (see notes to editors).

A new study by The Institute of Cancer Research, London (ICR) has shown that a genetic test for faults in DNA repair could enable targeted nuclear treatments for patients with prostate cancer.

Using super-high pressures similar to those found deep in the Earth or on a giant planet, Washington State University researchers have created a compact, never-before-seen material capable of storing vast amounts of energy.

Scientists have created a never-before seen type of exotic matter that is thought to have been present at the earliest stages of the universe, right after the Big Bang. The new matter is a particularly weird form of antimatter, which is like a mirror-image of regular matter. Every normal particle is thought to have an antimatter partner, and if the two come into contact, they annihilate. The recent feat of matter-tinkering was accomplished by smashing charged gold atoms at each other at super-high speeds in a particle accelerator called the Relativistic Heavy Ion Collider at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory in Upton, N.Y.