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M. F. Carruthers 《BMJ (Clinical research ed.)》1960,2(5216):1845-1847
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In July the yield of protein extractable from potato haulm could be 600 kg/ha and the beginning of September it is 200 kg/ha. The yield of fiber containing 1 to 2% N is less affected by maturity. The annual waste of extractable protein, suitable for feeding nonruminants, is about 60,000 tons. The contribution that some small changes in conventional potato husbandry might make to minimizing this waste is discussed. 相似文献
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Andrew J. Mashburn Jason T. Downer Bridget K. Hamre Laura M. Justice Robert C. Pianta 《应用发育科学》2013,17(4):179-196
MyTeachingPartner (MTP) is a teacher professional development program designed to improve the quality of teacher-child interactions in pre-kindergarten classrooms and children's language and literacy development. The program includes language/literacy activities and two Web-based resources—video exemplars of effective interactions and individualized consultation—designed to support teachers' high quality implementation of these activities. This study examined the impacts of the MTP Web-based resources on the language and literacy development of 1,165 children during pre-kindergarten. Children whose teachers were randomly assigned to receive access to both the video exemplars and participated in consultation (MTP Consultancy n = 65) made greater gains in receptive language skills during pre-kindergarten compared to children whose teachers were randomly assigned to receive access to the video exemplars only (MTP Video Library n = 69). Further, among MTP Consultancy teachers, more hours of participating in the consultation process was positively associated with children's receptive language development, and more hours implementing the language/literacy activities was positively associated with children's language and literacy development. Implications for improving children's school readiness and promoting teachers' participation in professional development programs are discussed. 相似文献
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G. Cabrera Walsh Y. Magalí Dalto Federico M. Mattioli Raymond I. Carruthers Lars W. Anderson 《BioControl》2013,58(1):133-147
Egeria densa (Hydrocharitaceae) is a submerged macrophyte from South America that is a weed in several countries. It crowds out native plants and hinders water use, causing economic and environmental damage. The leafminer fly Hydrellia sp. 1 (Diptera: Ephydridae), was found feeding in E. densa throughout its Argentine distribution, and is currently the only known specialist herbivore of E. densa. It was reared in the laboratory and tested on 25 plant species. This herbivore can cause heavy defoliation in the laboratory and in the field. Hydrellia sp. 1 was found only on E. densa, but in the laboratory it also developed on two other Hydrocharitaceae species in the same family; Egeria naias, and Elodea callitrichoides. Significant oviposition and feeding were only observed on its primary natural host, and to a lesser degree on E. naias. Field studies indicate Hydrellia sp. 1 is present in the field year round, unless the host plant is prostrate for long periods, or covered by floating macrophytes. These results indicate Hydrellia sp. 1 may be a suitable biocontrol candidate for E. densa. 相似文献
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The southern rock lobster, Jasus edwardsii, shows clear phenotypic differences between shallow water (red coloured) and deeper water (pale coloured) individuals. Translocations of individuals from deeper water to shallower waters are currently being trialled as a management strategy to facilitate a phenotypic change from lower value pale colouration, common in deeper waters, to the higher value red colouration found in shallow waters. Although panmixia across the J. edwardsii range has been long assumed, it is critical to assess the genetic variability of the species to ensure that the level of population connectivity is appropriately understood and translocations do not have unintended consequences. Eight microsatellite loci were used to investigate genetic differentiation between six sites (three shallow, three deep) across southern Tasmania, Australia, and one from New Zealand. Based on analyses the assumption of panmixia was rejected, revealing small levels of genetic differentiation across southern Tasmania, significant levels of differentiation between Tasmania and New Zealand, and high levels of asymmetric gene flow in an easterly direction from Tasmania into New Zealand. These results suggest that translocation among Tasmanian populations are not likely to be problematic, however, a re-consideration of panmictic stock structure for this species is necessary. 相似文献