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Post‐project appraisals (PPAs) are systematic assessments of built restoration projects, which provide feedback on performance of restoration approaches to improve future restoration efforts. Unfortunately, most restoration projects are not subject to systematic assessment because of lack of institutional arrangements to sustain long‐term evaluation and the orientation of most funding agencies towards project implementation rather than “studies.” As semester‐long courses on river restoration increasingly appear in university curricula at the graduate and advanced undergraduate level, independent student research projects for such courses can provide a mechanism for building a database of PPAs (and components thereof) and providing the students with a powerful learning experience. In two UC Berkeley courses, we require independent student projects involving original field research, peer review of first drafts, instructor (and often outside) review of second drafts, and presentation of results to a public symposium. Since 1995, the revised, final papers have been added to the University of California library, where they constitute one of the largest collections of restoration‐related studies currently available for any region: over 300 restoration‐related studies, of which 80 are PPAs or components thereof. Since 2003, the papers have been posted on‐line, with 40,000 full text downloads through 2010. Some term projects have directly influenced river restoration programs, inducing changes in salmon habitat enhancement project design, documenting failure of projects based on inappropriate restoration approaches, and contributing to systematic assessments of step‐pool and compound channel designs in urban areas. Student evaluations cite the term projects as valuable learning experiences.  相似文献   
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Hydrobiologia - Catchment-scale variation between lake habitats has the potential to simultaneously influence the trophic niche and parasite community of fish hosts. In this study, we investigated...  相似文献   
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The nuclear factor (NF)-κB is a primary regulator of inflammatory responses and may be linked to pathology associated with obesity. We investigated the progression of NF-κB activity during a 12-week feeding period on a high-fat diet (HFD) or a low-fat diet (LFD) using NF-κB luciferase reporter mice. In vivo imaging of luciferase activity showed that NF-κB activity was higher in the HFD mice compared with LFD-fed mice. Thorax region of HFD females displayed fourfold higher activity compared with LFD females, while no such increase was evident in males. In male HFD mice, abdominal NF-κB activity was increased twofold compared with the LFD males, while females had unchanged NF-κB activity in the abdomen by HFD. HFD males, but not females, exhibited evident glucose intolerance during the study. In conclusion, HFD increased NF-κB activity in both female and male mice. However, HFD differentially increased activity in males and females. The moderate increase in abdomen of male mice may be linked to glucose intolerance.  相似文献   
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This comparative study explores how low temperatures affect the mortality and growth of first generation hatchery-reared progeny of subarctic populations of Arctic charr (Salvelinus alpinus L.) and European whitefish (Coregonus lavaretus L.). Replicate fish groups where held under simulated natural light regimes (70°N) at three constant temperatures (1, 3 and 6°C). The mortality of Arctic charr was low (≤1.4%) at all temperature treatments, whereas the mortality of whitefish increased with decreasing temperature from 6% at 6°C to 33% at 1°C. The Arctic charr exhibited higher growth rates than whitefish at all three temperature regimes. All groups of Arctic charr increased in weight, whereas whitefish held at 1°C did not gain weight throughout the experimental period of 133 days. Arctic charr exhibited a large intraspecific variability in growth leading to large variations in size-structure, whereas whitefish in contrast showed very homogenous growth and size-structure patterns; a dissimilarity probably related to species-specific differences in antagonistic behaviour. Evidently, Arctic charr are more cold water adapted than whitefish and are able to maintain growth at extremely low temperatures. Arctic charr thus appear to be the most suitable species for aquaculture at low water temperatures.  相似文献   
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Background

Evidence from several studies show poor guideline adherence to COPD treatment, but no such study has been undertaken in Norway. The objectives of this study, was to estimate and compare the guideline adherence to COPD treatment in general population-based and hospital-recruited COPD patients, and find possible predictors of guideline adherence.

Methods

From the prospective, observational EconCOPD-study, we analysed guideline adherence for 90 population-based COPD cases compared to 245 hospital-recruited COPD patients. Overall guideline adherence was defined as correct pharmacological treatment, and influenza vaccination the preceding year, and having received smoking cessation advice. Multivariate logistic regression analysis was performed with the dichotomous outcome overall guideline adherence adjusting for relevant variables.

Results

The overall guideline adherence for population-based COPD cases was 6.7%, significantly lower than the 29.8% overall guideline-adherence amongst hospital-recruited COPD patients. Adherence to pharmacological treatment guidelines was 10.0 and 35.5%, for the two recruitment sources, respectively. GOLD-stage 3 to 4 was associated with significantly better guideline adherence compared to GOLD-stage 2 (OR (95% CI) 18.9 (8.37,42.7)). The unadjusted difference between the two recruitment sources was completely explained by degree of airflow obstruction.

Conclusion

Overall guideline adherence was very low for both recruitment sources. We call for increased attention from authorities and healthcare personnel to improve the quality of care given to this patient group.
  相似文献   
110.
Persistence of vascular plants in a Norwegian boreal coniferous forest   总被引:1,自引:0,他引:1  
Persistence, the tendency of a species to remain in its original position and not to colonize new sites, is studied for the most abundant forest vascular plants (25 species in spruce forest and 7 in pine forest) in Solhomfjell, Gjerstad, S Norway Data sets included presence/absence in 199 meso plots (1 m2) and 3184 subplots (1/16 m2), analyzed over a 5 yr interval, and a subset of 50 meso plots and 800 subplots, analyzed for six consecutive years Relationships between species variables (seedling frequency and mobility rate compiled from the literature, and cover and abundance means in the study area) are studied, and related to species optima along ecologically interpreted DCA ordination axes Vascular plant mobility may increase towards nutrient-poor sites Dominance in the boreal forest floor is mostly by clonal species Persistence was calculated for different temporal (1-5 yr) and spatial (1/16 and I m2) scales Persistence patterns in the spruce and pine forests were similar, but persistence decreased towards the xeric pine forests One main component of variation in persistence was demonstrated by PCA analyses the absolute level of persistence, which is related to seedling recruitment vs clonal growth, and within clonal species to ramet longevity, abundance, mobility, growth pattern and mode of surviving the infavourable season Minor components of variation in persistence were related to spatial scale and temporal scale Persistence characteristics were species-specific and varied little between years Numerous species characteristics were relevant to interpretation of variation in persistence, indicating a continuous, multidimensional variation in life history characteristics  相似文献   
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