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31.
Amphiphilic phospholipids were used to direct the formation of biocompatible, uniform silica nanostructures in the presence of Saccharomyces cerevisiae and bacterial cell lines. The cell surfaces organize multilayered phospholipid vesicles that interface coherently with the silica host and help relieve drying stresses that develop with conventional templates. These host structures maintain cell accessibility, addressability, and viability in the absence of buffer or an external fluidic architecture. The cell surfaces are accessible and can be used to localize added proteins, plasmids, and nanocrystals. Prolonged cell viability combined with reporter protein expression enabled stand-alone cell-based sensing.  相似文献   
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BACKGROUND: Although many school-based diet and physical activity interventions have been designed and evaluated, relatively few have been tested for the after-school setting. After-school day-care programmes at either elementary schools or private locations provide a ready-made opportunity for health programmes that may be difficult to incorporate into an already-full school day. The purpose of this paper is to report on a pilot study of an after-school adaptation of the CATCH (Coordinated Approach To Child Health) elementary school programme called the CATCH Kids Club (CKC). METHODS: The CKC was pilot-tested and formatively evaluated in 16 Texas after-school programmes: eight in El Paso and eight in Austin (four intervention and four reference sites each). Evaluation consisted of direct observation of moderate to vigorous physical activity during play time, self-reported food intake and physical activity, and focus group interviews with after-school programme staff. RESULTS: Students responded well to the physical activity and snack components and were less interested in the five-module education component. Routine staff training was a key variable in achieving proper implementation; the ideal would be a full day with repeated follow-up model teaching visits. Staff turnover was a logistic issue, as was programme leader readiness and interest in conducting the programme. Strong and significant effects were observed for the physical activity but not for the education component. The results of the physical education component suggest it is feasible, effective and ready for larger-scale evaluation or dissemination.  相似文献   
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We have used laser guide star adaptive optics and a near-infrared dual-channel imaging polarimeter to observe light scattered in the circumstellar environment of Herbig Ae/Be stars on scales of 100 to 300 astronomical units. We revealed a strongly polarized, biconical nebula 10 arc seconds (6000 astronomical units) in diameter around the star LkHalpha 198 and also observed a polarized jet-like feature associated with the deeply embedded source LkHalpha 198-IR. The star LkHalpha 233 presents a narrow, unpolarized dark lane consistent with an optically thick circumstellar disk blocking our direct view of the star. These data show that the lower-mass T Tauri and intermediate mass Herbig Ae/Be stars share a common evolutionary sequence.  相似文献   
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Five experiments were implemented to collect information related to the effects of fluazifop-p-butyl (active chemical in grass selective herbicides, Fusilade® and Fusilade Forte™) on seed germination, seedling emergence, growth and health of species native to southwest Australia (a grass and non-grasses), together with several co-occurring introduced species (grasses and a non-grass). Experiments investigated effects of herbicide concentrations, seed burial depths, seed-sowing times since herbicide application and application locations (foliage versus soil). Both herbicides, at half to quadruple strength of recommended field application concentrations, adversely affected development of native and introduced species, both grasses and non-grasses. Herbicidal effects were observed during the seed germination phase, and if germination had occurred, during seedling emergence and, finally, during plant establishment. However, effects were more pronounced after seed germination, particularly on development of seedlings and plants, with retardation and/or discoloration of either radicles or shoots. Not unexpectedly, seedlings from seeds buried deeper in the sand medium (20 mm) struggled to emerge. Both herbicides demonstrated residual characteristics by impeding seedling emergence and growth from seeds sown at various dates (up to maximum test duration of 3 weeks) following exposure of the sand medium to the herbicides. Further, herbicide application to sand only, produced effects on 5-6 months old plants that were similar as application to foliage only, demonstrating herbicide uptake from sand. While the findings support independent research, they contradict the purported herbicide characteristics by commercial sources - grass selective, post-emergent, non-residual, rapid breakdown and active through foliar application only. Implications of these herbicides for biodiversity conservation are discussed.  相似文献   
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Over the past 50 years, forested landscapes of the Pacific Northwest have become increasingly patchy, dominated by early successional forests. Several amphibian species associated with forested headwater systems have emerged as management concerns, especially after clearcutting. Given that headwater streams comprise a large portion of the length of flowing waterways in western Oregon forests, there is a need to better understand how forest management affects headwater forest taxa and their habitats. Mitigation strategies include alternatives to clearcutting, such as harvests that remove only part of the canopy and maintenance of riparian buffer strips. Our study investigates effects of upland forest thinning coupled with riparian buffer treatments on riparian and upland headwater forest amphibians, habitat attributes, and species-habitat associations. Amphibian captures and habitat variables were examined 5–6 years post-thinning within forest stands subject to streamside-retention buffers and variable-width buffers, as well as unthinned reference stands. We found no treatments effects, however, our results suggest that ground surface conditions (e.g., amount of rocky or fine substrate) play a role in determining the response of riparian and upland amphibians to forest thinning along headwater streams. Distance from stream was associated with amphibian abundance, hence retention of riparian buffers is likely important in maintaining microclimates and microhabitats needed for amphibians and other taxa. Moderate thinning and preservation of conditions in riparian and nearby upland areas by way of variable-width and streamside-retention buffers may be sufficient to maintain suitable habitat and microclimatic conditions vital to amphibian assemblages in managed headwater forests.  相似文献   
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Appendicular osteosarcoma (OSA) remains a prevalent musculoskeletal cancer in dogs and definitive local control followed by adjuvant cytotoxic chemotherapy is considered the gold standard approach. Several studies support surgical limb salvage as a means of local control with similar outcomes compared with limb amputation. Complications are well described for limb salvage but little is known of dogs that undergo secondary amputation as a result of complications and outcomes specific to this group. A retrospective analysis of dogs in an institutional primary bone tumour registry was performed to identify dogs diagnosed with histologically confirmed OSA treated with surgical limb salvage with a technique that required an implant to reconstruct the osseous defect. A total of 192 dogs were identified with 31 dogs undergoing secondary amputation representing a limb preservation rate of 84%. A total of 111 dogs were analysed: 31 secondary amputation cases and 80 controls were selected for comparison. The most common reasons for secondary amputation were local recurrence (LR) and surgical site infection (SSI), with odds ratios of 3.6 and 1.7, respectively. Dogs that underwent secondary amputation had a significantly (P = .05) longer median disease specific survival time (ST) (604 days) compared with the control group (385 days). Dogs lived for a median of 205 days beyond secondary amputation and 97% had good functional outcome. Significant independent factors that positively influenced ST were secondary amputation, moderate SSI, severe SSI and age.  相似文献   
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