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USGS scientists have detected toxins known as microcystins produced by various forms of algae in 39 percent of the small streams assessed throughout the southeastern United States. Their recent study looked at 75 streams in portions of Alabama, Georgia, North Carolina, South Carolina and Virginia.

Asteroids headed for a collision with the Earth, if found early enough, can be acted upon to prevent the potentially devastating consequences of an impact. One technique to divert an asteroid, called kinetic impact, uses a spacecraft to crash into the body at high speeds.

This approach delivers the momentum of the spacecraft, while also providing an additional boost of momentum through the production of impact crater ejecta exceeding the asteroid’s escape velocity. Researchers at Lawrence Livermore National Laboratory (LLNL) have been studying the effectiveness of the kinetic-impactor strategy by carrying out 3D simulations of the process.

In a new paper published in Icarus(link is external), LLNL planetary defense researchers find that asteroid deflection by kinetic impact is sensitive to a range of asteroid characteristics, including strength, porosity, rotation and shape. These and other asteroid properties may not be well constrained before an actual deflection mission is staged, leading to variability in the deflection outcome. By simulating a range of initial conditions for the target asteroids, researchers were able to quantify, for example, how greater target strength decreases the delivered momentum impulse and how, for an asteroid of constant size, added porosity can result in more effective deflections, despite the dampening of the shock waves produced during an impact

Adults with long-term exposure to ozone (O3) face an increased risk of dying from respiratory and cardiovascular diseases, a study  “Long-Term Ozone Exposure and Mortality in a Large Prospective Study” published online ahead of print in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine suggests.

Using data from a large U.S. study begun in 1982, researchers found that every additional 10 parts per billion (ppb) in long-term ozone exposure increased the risk of dying by:

• 12 percent from lung disease
• 3 percent from cardiovascular disease
• 2 percent from all causes

Researchers said the increased risk of death was highest for diabetes (16 percent), followed by dysrhythmias, heart failure and cardiac arrest (15 percent) and by COPD (14 percent).

Natural disasters made 2015 a miserable year for many people around the world. According to the United Nations’ Office for Disaster Risk Reduction, the statistics were brutal. At least 98.6 million people were affected by natural disasters ranging from droughts to floods, and the economic damage could have been as high as $66.5 billion. Using the data available from the Belgian non-profit Center for Research on the Epidemiology of Disasters (CRED), the UN reports that almost 23,000 people died from the 346 natural disasters reported across the world.

Nuevas investigaciones muestran que más de 5,5 millones de personas mueren prematuramente cada año debido a la contaminación del aire en los hogares y en el exterior. Más de la mitad de las muertes se producen en dos de las economías de más rápido crecimiento del mundo: China e India.