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61.
Nancy Grudens-Schuck Will Allen Tasha M. Hargrove Margaret Kilvington 《Agriculture and Human Values》2003,20(1):53-64
Dependency stands for manygrievances and is generally considered asymptom of oppression. An opposing concept,offered as the preferred state, isself-reliance. Dependency and self-reliance arekey concepts in sustainable developmentprograms that feature participatory approaches.Some of the ways in which development projectsemploy the concepts of dependency andself-reliance, however, are troubling.Dependency and self-reliance in two programsfor participatory sustainable development areexamined, one in Canada and the other in NewZealand. Frameworks for dependency and self-reliance aredrawn from social psychology and philosophy toexamine problematic aspects associated with theconcepts. Analysis produced a proposal foruse of the term situatedinterdependence as a way to cast the outcomesof participatory sustainable development moreprecisely. The location of the cases (Canadaand New Zealand) centers the discussion withina context of industrialized agriculture, butalso points to issues pertinent to developingcountries. 相似文献
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Trifilo MJ Yajima T Gu Y Dalton N Peterson KL Race RE Meade-White K Portis JL Masliah E Knowlton KU Chesebro B Oldstone MB 《Science (New York, N.Y.)》2006,313(5783):94-97
We investigated extraneural manifestations in scrapie-infected transgenic mice expressing prion protein lacking the glycophosphatydylinositol membrane anchor. In the brain, blood, and heart, both abnormal protease-resistant prion protein (PrPres) and prion infectivity were readily detected by immunoblot and by inoculation into nontransgenic recipients. The titer of infectious scrapie in blood plasma exceeded 10(7) 50% infectious doses per milliliter. The hearts of these transgenic mice contained PrPres-positive amyloid deposits that led to myocardial stiffness and cardiac disease. 相似文献
64.
Holmes CB Thirumurthy H Padian NS Goosby EP 《Science (New York, N.Y.)》2010,330(6001):176-7; author reply 177-8
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Russell CA Jones TC Barr IG Cox NJ Garten RJ Gregory V Gust ID Hampson AW Hay AJ Hurt AC de Jong JC Kelso A Klimov AI Kageyama T Komadina N Lapedes AS Lin YP Mosterin A Obuchi M Odagiri T Osterhaus AD Rimmelzwaan GF Shaw MW Skepner E Stohr K Tashiro M Fouchier RA Smith DJ 《Science (New York, N.Y.)》2008,320(5874):340-346
Antigenic and genetic analysis of the hemagglutinin of approximately 13,000 human influenza A (H3N2) viruses from six continents during 2002-2007 revealed that there was continuous circulation in east and Southeast Asia (E-SE Asia) via a region-wide network of temporally overlapping epidemics and that epidemics in the temperate regions were seeded from this network each year. Seed strains generally first reached Oceania, North America, and Europe, and later South America. This evidence suggests that once A (H3N2) viruses leave E-SE Asia, they are unlikely to contribute to long-term viral evolution. If the trends observed during this period are an accurate representation of overall patterns of spread, then the antigenic characteristics of A (H3N2) viruses outside E-SE Asia may be forecast each year based on surveillance within E-SE Asia, with consequent improvements to vaccine strain selection. 相似文献
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Jen JC Chan WM Bosley TM Wan J Carr JR Rüb U Shattuck D Salamon G Kudo LC Ou J Lin DD Salih MA Kansu T Al Dhalaan H Al Zayed Z MacDonald DB Stigsby B Plaitakis A Dretakis EK Gottlob I Pieh C Traboulsi EI Wang Q Wang L Andrews C Yamada K Demer JL Karim S Alger JR Geschwind DH Deller T Sicotte NL Nelson SF Baloh RW Engle EC 《Science (New York, N.Y.)》2004,304(5676):1509-1513
The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing. 相似文献
69.
Spatial Variability of Agricultural Soil Fertility Parameters in a Gleyic Podzol of Belgium 总被引:1,自引:0,他引:1
Precise information about the spatial variability of soil nutrients is essential in developing site-specific management, e.g., variable rate application of nutrients. In this study 5 fields (4 grassland, 1 arable land) on a Gleyic Podzol, each of about 1 ha, were sampled according to a 20 m×20 m grid. On these samples pH, carbon content and nutrient status (P, K, Ca, Mg, and Na) were measured. The variogram analysis of the different soil fertility parameters revealed quite different ranges for these parameters. Carbon content, pH and calcium have high ranges, between 110 and 170 m. On the other hand, ranges for potassium and sodium are much smaller, 60 m and 30 m respectively. For the elements potassium and sodium, high coefficients of variation are found, especially on the grassland fields. These differences in ranges of spatial relationship indicate that the sampling strategy for estimating variability of soil fertility, should be adopted to the different selected soil parameters and the soil use. 相似文献
70.
Chatham K Callan Charles W Laidley Linda J Kling Nancy E Breen Andrew L Rhyne 《Aquaculture Research》2014,45(7):1176-1186
This study was conducted to determine the effects of dietary highly unsaturated fatty acids (HUFA) on flame angelfish (Centropyge loriculus) reproduction, and egg and larval quality. In the experiment, formulated diets containing 1.8, 2.9 or 3.6% n‐3 HUFA were fed to flame angelfish broodstock (n = 4) for 5 months. Mean fecundity (daily egg production), egg fertilization rates and embryo viability were used as indicators of egg quality. In addition, mean egg diameter, oil globule diameter, per cent hatch, larval size at hatch, per cent survival to yolk exhaustion and larval size at yolk exhaustion were recorded for each treatment. Flame angelfish fed the diet containing 3.6% n‐3 HUFA exhibited significantly increased fecundity, fertilization rates and embryo viability than fish that were fed the other two formulated diets. Egg diameter, egg oil globule diameter, larval size at hatch, larval survival to yolk exhaustion and larval size at yolk exhaustion from the 3.6% n‐3 HUFA broodstock treatment group were not significantly different from those derived from the Control broodstock treatment. These data revealed that flame angelfish egg quality could respond rapidly (within weeks) to maternal dietary changes. Results from this study further support that dietary HUFA composition can significantly affect broodstock reproductive performance as well as subsequent performance of eggs and larvae. 相似文献