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991.
In order to increase farm safety awareness and teach children good safety habits, farm safety day camp programs have been initiated in many communities. For the most part, the effectiveness of the programs is unknown because few evaluations have been performed. The purpose of this project was to qualitatively assess the overall strengths and weaknesses of farm safety day camp programs and to generate recommendations for future programs. Interviews, a literature search, and observations were used to identify strengths and weaknesses of the farm safety day camp programs. Major strengths of the programs are that: 1) positive attention is given to agriculture and agricultural safety; 2) programs are hands-on, interactive, and fun; 3) children gain knowledge about farm safety; 4) programs bring a community together to work toward a common goal; and 5) children talk to parents about safety. Key weaknesses of farm safety day camp programs are that: 1) there is a lack of parental involvement in many of the programs; 2) it is hard to change patterns of behavior in one day; 3) programs are expensive and time consuming; 4) curricula may include content that is inaccurate or inappropriate for the age of participants; and 5) evaluation is difficult. When done well, farm safety day camp programs can teach children about safety and influence safety practices affecting children on the farm. Recommendations for future farm safety day camp programs are: 1) ensure that child-development principles are applied to all aspects of program activities and curricula; 2) provide session leaders with accurate and relevant content; 3) increase parental involvement; and 4) address safety issues throughout the year.  相似文献   
992.
The soil erosion research and soil and water conservation global community lost a treasured member on November 20, 2020, when Dr. John Matthew Laflen (Fig. 1) died. Always one with a friendly welcoming smile, John had hundreds of friends, both personally and professionally throughout the world. This article includes many of his professional and scientific contributions, and impacts from his research and outreach activities.  相似文献   
993.
Widespread spontaneous evacuation, the tendency for people to evacuate even when not advised to do so, has been highlighted as one of the likely behavioral responses to a nuclear power plant emergency. Utility company representatives contend that protective action advisories can be structured so as to stifle the magnitude and geographic extent of spontaneous evacuation. Data from a utility-company-sponsored telephone survey of households on Long Island, New York, where the Shoreham Nuclear Power Station is located, are used in this paper to test this proposition. Analyses of responses given to three sets of increasingly serious reactor accident scenarios, with and without information instructing people what protective actions to take, raise serious questions about the ability of emergency notification messages to affect human behavior in a radiological emergency. The results suggest firstly, that even if people me specifically advised not to evacuate, most would be inclined to do so; and secondly, that attempts to stifle the propensity to evacuate among those who are not at risk are likely to increase the propensity to stay behind among those who are at risk and should evacuate.  相似文献   
994.
A major challenge of computational protein design is the creation of novel proteins with arbitrarily chosen three-dimensional structures. Here, we used a general computational strategy that iterates between sequence design and structure prediction to design a 93-residue alpha/beta protein called Top7 with a novel sequence and topology. Top7 was found experimentally to be folded and extremely stable, and the x-ray crystal structure of Top7 is similar (root mean square deviation equals 1.2 angstroms) to the design model. The ability to design a new protein fold makes possible the exploration of the large regions of the protein universe not yet observed in nature.  相似文献   
995.
Fluvial ways     
Baker V 《Science (New York, N.Y.)》1994,266(5189):1414-1415
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996.
Events that stall bacterial protein synthesis activate the ssrA-tagging machinery, resulting in resumption of translation and addition of an 11-residue peptide to the carboxyl terminus of the nascent chain. This ssrA-encoded peptide tag marks the incomplete protein for degradation by the energy-dependent ClpXP protease. Here, a ribosome-associated protein, SspB, was found to bind specifically to ssrA-tagged proteins and to enhance recognition of these proteins by ClpXP. Cells with an sspB mutation are defective in degrading ssrA-tagged proteins, demonstrating that SspB is a specificity-enhancing factor for ClpXP that controls substrate choice.  相似文献   
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Thermostabilizing an enzyme while maintaining its activity for industrial or biomedical applications can be difficult with traditional selection methods. We describe a rapid computational approach that identified three mutations within a model enzyme that produced a 10 degrees C increase in apparent melting temperature T(m) and a 30-fold increase in half-life at 50 degrees C, with no reduction in catalytic efficiency. The effects of the mutations were synergistic, giving an increase in excess of the sum of their individual effects. The redesigned enzyme induced an increased, temperature-dependent bacterial growth rate under conditions that required its activity, thereby coupling molecular and metabolic engineering.  相似文献   
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