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Fighting Weeds With Plant Pathogens
"The use of plant pathogens to suppress weeds is considered as one of the alternative weed control options for areas or production systems where the use of chemical herbicides is not permitted or feasible," said Erin Rosskopf, USDA, Agricultural Research Service, Fort Pierce, FL. "Plant pathogens may also be used when the herbicide selection or usage must be rotated with other control methods in order to prevent the development of resistant weeds or lessen the impact of herbicides on the environment," she said. Weed management is important due to the amount of damage weeds can cause to agricultural productivity. Weeds can reduce crop yields by as much as 12 percent (causing up to $32 billion in losses), based on the potential value of all U.S. crops of approximately $267 billion/year. Weeds also pose serious ecological problems. Invasive weeds are capable of altering ecosystem processes and displacing native plant and animal species. In addition, weeds serve as reservoirs for plant pathogens that impact crops. As per Rosskopf, there are two approaches used for managing weeds with plant pathogens-the classical biological control approach and the bioherbicides approach. The classical biocontrol approach uses a pathogen imported from a foreign location to control a native or naturalized weed with minimal technological manipulations......... Posted by: Jessica Permalink Source High-flying balloons track hurricane formation
The first launch of a balloon with its instruments, called a driftsonde, took place at Zinder, Niger, on Aug. 28. Some seven more driftsondes will be released from Zinder through late September, coinciding with the peak period of hurricane formation over the tropical Atlantic. "Data from the driftsondes should help characterize the conditions that either foster or suppress hurricane formation," said the National Science Foundation's (NSF) Cliff Jacobs, who oversees support for the National Center for Atmospheric Research (NCAR) in Boulder, Colo. Researchers and engineers at NCAR and the French space agency, CNES, developed the driftsondes. The research was funded by NSF, NCAR's primary sponsor, and the National Oceanic and Atmospheric Administration. Each balloon will drift from Africa toward the Caribbean at heights of around 65,000-70,000 feet, where light easterly winds prevail. Twice a day, each balloon will release an instrument known as a dropsonde that falls by parachute, sensing the weather conditions during its 20-minute descent and sending data back to the balloon and then to the scientists by satellite......... Posted by: Tyler Permalink Source Nutritional Value Of Salad
A new UCLA/Louisiana State University study of dietary data on more than 17,500 men and women finds consumption of salad and raw vegetables correlates with higher concentrations of folic acid, vitamins C and E, lycopene and alpha and beta carotene in the bloodstream. Published in the September edition of the peer-reviewed Journal of the American Dietetic Association, the study also suggests that each serving of salad consumed correlates with a 165 percent higher likelihood of meeting recommended dietary allowances (RDA) for vitamin C in women and 119 percent greater likelihood in men. The study is the first to examine the relationship between normal salad consumption and nutrient levels in the bloodstream, and also the first to examine the dietary adequacy of salad consumption using the latest nutritional guidelines of the Food and Nutrition Board of the National Academy of Sciences. The findings blunt concerns about the human body's ability to absorb nutrients from raw vegetables, as well as concern that the structure and characteristics of some plants undercut nutritional value. "The consistently higher levels of certain nutrients in the bloodstream of salad-eaters suggest these important components of a healthy diet are being well-absorbed from salad," said Lenore Arab, visiting professor of epidemiology at the UCLA School of Public Health and co-author of the study with L. Joseph Su, assistant professor at the LSU School of Public Health......... Posted by: Sean Permalink Source eMachines Model T6536
Full review is available at PCMag site......... Posted by: Kevin Permalink Source A better water test
A new method for detection and measurement of small amounts of water, developed in the lab of Dr. Milko van der Boom in the Weizmann Institute's Organic Chemistry Department, might allow such tests to be performed accurately and quickly. Van der Boom and postdoctoral fellow Dr. Tarkeshwar Gupta created a versatile film on glass that is only 1.7 nanometers thick. The film can measure the number of water molecules in a substance even when it contains only a few parts per million. "The problem," says van der Boom, "is that water is hard to detect and to quantify." His method is a departure from prior sensing techniques. In general, such sensor systems are based on relatively weak but selective "host-guest" interactions. In the Weizmann Institute team's sensor, metal complexes embedded in the film steal electrons from the water molecules. When the number of electrons in the metal complexes changes, so does their color, and this change can be read optically. Devices based on optical readout do not need to be wired directly to larger-scale electronics an issue that's still a tremendous challenge for much of molecular-based electronics......... Posted by: Sarah Permalink Source Thinking Of Stroke
Does motor lateralization have implications for stroke rehabilitation? pg. 311. This article describes current findings on the usefulness of dominance retraining strategies in poststroke patients with dominant-arm hemiplegia. We found consistent differences in control strategies used by both the dominant and nondominant hemisphere/limb systems. However, the nondominant arm may not spontaneously become an efficient dominant manipulator, indicated by persistent deficits in chronic stroke patients. Because ipsilesional deficits are commonly mild compared with contralesional, they are not normally addressed in rehabilitation. We propose that the previously nondominant limb impeded by motor deficits could benefit from remedial treatment to help switch to a dominant controller......... Posted by: Sean Permalink honoring African American chemist Percy Julian
Pioneering chemist Percy Julian subject of upcoming NOVA documentary.
One of the sessions at the symposium -- "Dr. Percy L. Julian Scientist, Humanist, Educator, Entrepreneur, and Inspirational Trailblazer" -- will offer a sneak preview of the documentary, which is entitled, "Forgotten Genius," written and produced by Llewellyn Smith, writer/producer/director of Vital Pictures, Inc.; Steve Lyons, writer/producer of Moreno, Lyons Productions LLC; and Melanie Wallace, senior series producer, NOVA/WGBH. "Forgotten Genius" is, as per Smith, "a first time portrait of this remarkable American chemist The NOVA documentary brings to the public the forgotten achievements of this 20th century scientist." The film is part of NOVA's Lives in Science series. Percy Lavon Julian was born in Montgomery, Ala., on April 11, 1899. The son of a railway clerk and the grandson of slaves, his early schooling was spotty in the segregated South of the early 20th century. Even so, he was accepted as a freshman at DePauw University in Greencastle, Ind., at the age of 17; he graduated first in his class in 1920. He then taught for two years at Fisk University before enrolling in a Master's program at Harvard......... Posted by: Sarah Permalink Source Lead Poisoning In Condors
Lead poisoning is a major factor limiting the success of efforts to rebuild populations of the endangered California condor. Since the mid-1980s, condors have been bred in captivity and released back into the wild in California, Arizona, and Baja California. The birds, which feed on carrion, can ingest lead from ammunition in animal carcasses or gut piles left behind by hunters. The UCSC researchers used a "fingerprinting" technique based on the unique isotope ratios found in different sources of lead. The technique enabled them to match the lead in blood samples from condors to the lead in ammunition. Their findings were published online today by the journal Environmental Science & Technology. "There had been anecdotal reports for years about condors being exposed to lead from ammunition, but there was never enough clear evidence to document the extent of the problem. We knew that we could probably identify the sources of the lead using isotopic signatures," said Donald Smith, professor and chair of environmental toxicology at UCSC and a coauthor of the paper......... Posted by: Ashley Permalink Source Juices Reduces Alzheimer's Risk
The study by Qi Dai, M.D., Ph.D., assistant professor of Medicine, and colleagues appears in the recent issue of The American Journal of Medicine. The researchers followed a subset of subjects from a large cross-cultural study of dementia, called the Ni-Hon-Sea Project, which investigated Alzheimers disease and vascular dementia in older Japanese populations living in Japan, Hawaii and Seattle, Wash. For the current study, called the Kame Project, the researchers identified 1,836 dementia-free subjects in the Seattle population and collected information on their dietary consumption of fruit and vegetable juices. They then assessed cognitive function every two years for up to 10 years. After controlling for possible confounding factors like smoking, education, physical activity and fat intake, the researchers found that those who reported drinking juices three or more times per week were 76 percent less likely to develop signs of Alzheimers disease than those who drank less than one serving per week......... Posted by: Sean Permalink Source Alcohol Exposure Brain Link
These researchers also confirmed the involvement of additional proteins previously suggested as targets of alcohol toxicity, and observed abnormal behavior in the fish resulting from chronic alcohol exposure. These results are published in the online edition of the European Journal of Pharmacology. Researchers have found that five proteins are overexpressed and three were underexpressed. These proteins are thought to be involved in critical mechanisms such as programmed cell death, cholesterol balance, amino acid metabolism, oxidative stress and signal transduction. "Identification of proteins that show selective changes in abundance after alcohol exposure has the potential to unlock new pathways both for understanding the mechanisms of alcoholism and alcohol toxicity, as well as its amelioration," said Richard A. Rabin, Ph.D., professor in the UB Department of Pharmacology and Toxicology and senior author on the study. Senthilkumar Damodaran, doctoral student in pharmacology, is first author. The study involved 16 long-fin striped zebrafish, in two trials of eight each, which were placed as a group in a tank with ethyl alcohol for four weeks. Rabin said the researchers chose zebrafish because they are easy to breed and maintain, their DNA sequences are similar to that of humans and they are sensitive to alcohol concentrations......... Posted by: Sean Permalink Source |
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