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Agroforestry Systems - Intensive agriculture can result in increased runoff of sediment and agricultural chemicals that pollute streams. Consensus is emerging that, despite our best efforts, it is... 相似文献
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Wood products used in exterior applications must be protected against biodeterioration by decay fungi, insects such as termites, and other organisms. Traditionally, wood products for residential or industrial applications have been protected by treatment with chromated copper arsenate (CCA) or older inexpensive organic biocides, but environmental and disposal concerns and governmental regulations have resulted in a rapid and dramatic worldwide shift to copper-based systems. The current development trend is towards employing totally organic biocides based on relatively benign and expensive agrochemicals, with continuing research directed towards developing non-biocidal methods to protect wood. 相似文献
96.
Luo G Malkova S Yoon J Schultz DG Lin B Meron M Benjamin I Vanysek P Schlossman ML 《Science (New York, N.Y.)》2006,311(5758):216-218
Mean field theories of ion distributions, such as the Gouy-Chapman theory that describes the distribution near a charged planar surface, ignore the molecular-scale structure in the liquid solution. The predictions of the Gouy-Chapman theory vary substantially from our x-ray reflectivity measurements of the interface between two electrolyte solutions. Molecular dynamics simulations, which include the liquid structure, were used to calculate the potential of mean force on a single ion. We used this potential of mean force in a generalized Poisson-Boltzmann equation to predict the full ion distributions. These distributions agree with our measurements without any adjustable parameters. 相似文献
97.
Eben N. Broadbent Angélica M. Almeyda Zambrano Rodolfo Dirzo William H. Durham Laura Driscoll Patrick Gallagher Rosalyn Salters Jared Schultz Angélica Colmenares Shannon G. Randolph 《Landscape Ecology》2012,27(5):731-744
Development in biodiversity rich areas is of global concern. While development may lead to socioeconomic benefits, this often
comes concomitant with biodiversity loss and deforestation. Biodiversity rich areas present the opportunity for both improvements
in socioeconomic conditions and conservation; however numerous challenges exist. Costa Rica’s Manuel Antonio National Park
presents an ideal case study to investigate the balance between alternative forms of development which have contrasting environmental
impacts. The Manuel Antonio region is a highly dynamic landscape experiencing deforestation, from agriculture, cattle ranching
and oil palm plantations; and also reforestation from abandonment of land holdings and nature oriented tourism. Landscape
dynamics are closely intertwined with the livelihoods and perspectives on biodiversity conservation of local communities,
determining ecological sustainability. We use an analysis combining multi-temporal remote sensing of land cover dynamics from
1985 to 2008 with questionnaire data from local families on their socioeconomic status, perspectives on conservation, and
perceived changes in local wildlife populations. Our results show that, while regeneration occurred and forest fragmentation
in the area decreased from 1985 to 2008, Manuel Antonio National Park is rapidly becoming isolated. Decreasing ecological
connectivity is related to the rapid expansion of oil palm plantations adjacent to the park and throughout the lowland areas.
Perceived decreases in wildlife abundance and compositional change are evident throughout the area, with local communities
attributing this primarily to illegal hunting activities. Nature based tourism in the area presents an effective strategy
for conservation, including reductions in hunting, through increased valuation of biodiversity and protected areas, and socioeconomic
advantages. However, without urgent efforts to limit deforestation and preserve the remaining forested corridor connecting
the park to core primary forest, the ability to maintain biodiversity in the park will be reduced. 相似文献
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Identification of small molecule activators of cryptochrome 总被引:1,自引:0,他引:1
T Hirota JW Lee PC St John M Sawa K Iwaisako T Noguchi PY Pongsawakul T Sonntag DK Welsh DA Brenner FJ Doyle PG Schultz SA Kay 《Science (New York, N.Y.)》2012,337(6098):1094-1097
Impairment of the circadian clock has been associated with numerous disorders, including metabolic disease. Although small molecules that modulate clock function might offer therapeutic approaches to such diseases, only a few compounds have been identified that selectively target core clock proteins. From an unbiased cell-based circadian phenotypic screen, we identified KL001, a small molecule that specifically interacts with cryptochrome (CRY). KL001 prevented ubiquitin-dependent degradation of CRY, resulting in lengthening of the circadian period. In combination with mathematical modeling, our studies using KL001 revealed that CRY1 and CRY2 share a similar functional role in the period regulation. Furthermore, KL001-mediated CRY stabilization inhibited glucagon-induced gluconeogenesis in primary hepatocytes. KL001 thus provides a tool to study the regulation of CRY-dependent physiology and aid development of clock-based therapeutics of diabetes. 相似文献
100.
Daniel Schenkman DVM PhD Anibal Armien DVM PhD Roy Pool Jr. DVM PhD James M. Williams PhD Ronald D. Schultz PhD Jorge O. Galante MD 《Journal of Equine Veterinary Science》2009,29(10):748-752
Recently Degenerative Suspensory Ligament Desmitis (DSLD) has been proposed to be a disease characterized by systemic deposition of proteoglycan (PG) in connective tissues. To investigate this hypothesis, 6 clinically affected Peruvian Paso horses were compared to 2 unaffected quarterhorses and one unaffected standardbred. Histological sections of limb ligaments and tendons, nuchal ligaments, aortas, hearts, eyes, visceral organs and brains from both groups were stained with H&E as well as special stains for PG. Safranin-O stained sections were found to be optimal for elucidating the presence of PG. Although lesions characteristic of DSLD were present in suspensory ligaments of each clinically affected horse, including foci of chondroid metaplasia with abundant PG, a similar but less pronounced pattern of PG deposition was present in control horses. In contrast to findings of the previous study, PG deposition was not unique to DSLD horses, and PG deposition in aortas and nuchal ligaments of some control horses exceeded levels of PG present in similar tissue of DSLD horses. Furthermore, the “vascular lesion” described in the media of arteries as cellular separation and intercellular amorphous matrix deposition was within the spectrum of changes recognized in both affected and unaffected horses. We found no evidence that DSLD is a systemic PG deposition disease. 相似文献