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731.
Land suitability analysis for the upper Gila River watershed 总被引:7,自引:0,他引:7
In the United States, federal management agencies, such as the U.S. Forest Service and the U.S. Bureau of Land Management are required to assess the capability of land for future use. In addition, Arizona law now requires local jurisdictions to prepare comprehensive and general plans. Suitability analysis can be used for compliance with several elements of these plans. Here, a framework for land suitability analysis is presented for the upper Gila River watershed in Arizona and New Mexico. The framework is based on a thorough ecological inventory of the watershed. A goal of suitability analysis is to explicitly identify constraints and opportunities for future land conservation and development. This is accomplished by determining the fitness of a given tract of land for a defined use. Four land uses were targeted by local officials for analysis: low-density housing, commercial development, industrial development, and recreation. The framework can be useful for natural resource management as well as town, city, county, and federal planning in the watershed. 相似文献
732.
Measurement and analysis of IP network usage and behavior 总被引:14,自引:0,他引:14
Caceres R. Duffield N. Feldmann A. Friedmann J.D. Greenberg A. Greer R. Johnson T. Kalmanek C.R. Krishnamurthy B. Lavelle D. Mishra P.P. Rexford J. Ramakrishnan K.K. True F.D. van der Memle J.E. 《Communications Magazine, IEEE》2000,38(5):144-151
Traffic, usage, and performance measurements are crucial to the design, operation and control of Internet protocol networks. This article describes a prototype infrastructure for the measurement, storage, and correlation of network data of different types and origins from AT&T's commercial IP network. We focus first on some novel aspects of the measurement infrastructure, then describe analyses that illustrate the power of joining different measured data sets for network planning and design 相似文献
733.
Andersen Barbara L.; Cyranowski Jill M.; Aarestad Susan 《Canadian Metallurgical Quarterly》2000,126(3):380
The authors comment on three aspects of R. F. Baumeister's (2000) (see record 2000-15386-001) theoretical article on female sexuality. Questioning the predominance of nature versus cultural factors in accounting for sexual outcomes for men and women, the authors draw attention to the similarities (as opposed to differences) in the sexual attitudes, behaviors, and responses of men and women, and directly question the suggestion of "controlling" women's sexual attitudes, behaviors, responses, etc. to meet social needs for change. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
734.
Major advances in disease prevention in dairy cattle 总被引:1,自引:0,他引:1
LeBlanc SJ Lissemore KD Kelton DF Duffield TF Leslie KE 《Journal of dairy science》2006,89(4):1267-1279
This paper describes some of the major points of progress and challenges in health management of dairy cattle in the last 25 yr. A selection of the leading contributors in the field is acknowledged. Specific advances in the areas of transition cow management, epidemiology, udder health, applied immunology, housing design, calf health, and health-monitoring tools are described. The greatest advances in dairy health in the last 25 yr have been the shifts to disease prevention, rather than treatment, as well as from focus on individual animals to groups and herds. A fundamental advancement has been recognition of the multifactorial nature of almost all diseases of importance in dairy cattle. Epidemiology has been a critical new tool used to describe and quantify the interconnected risk factors that produce disease. Another major advance has been redefining disease more broadly, to include subclinical conditions (e.g., subclinical mastitis, ketosis, rumen acidosis, and endometritis). This expansion resulted both from improved technology to measure function at the organ level and, just as importantly, from the evolution of the health management paradigm in which any factor that limits animal or herd performance might be considered a component of disease. Links between cattle and people through consideration of environmental or ecosystem health are likely to further expand the concept of disease prevention in the future.Notable successes are decreases in the incidence of milk fever, clinical respiratory disease in adults, contagious mastitis, and clinical parasitism. There has also been improved protection through vaccination against coliform mastitis and bovine virus diarrhea. Since 1980, average herd size and milk production per cow have increased dramatically. Despite these increased demands on cows’ metabolism and humans’ management skills, the incidence of most common and important diseases has remained stable. Great progress has been made in understanding the biology of energy metabolism and immune function in transition dairy cows, the time at which the majority of disease occurs. Coupled with an emerging understanding of how best to provide for dairy cows’ behavioral needs, transition cow management promises to be the foundation for progress in maintenance and enhancement of the health of dairy cows in the next 25 yr. 相似文献
735.
Wishart JA Osborn M Gent ME Yen K Vujovic Z Gitsham P Zhang N Ross Miller J Oliver SG 《Yeast (Chichester, England)》2006,23(4):325-331
736.
BACKGROUND: Cocaine hydrochloride (C(17)H(21)NO(4)) is a powerful neuro-stimulatory alkaloid salt which has been abused by many cultures for thousands of years. Crack-cocaine, a derivative of cocaine, has gained notoriety for giving a quick "high" at a relatively lower cost. Crack-cocaine exposure has been reported to cause corneal disturbances ranging from subtle superficial punctuate keratitis to perforation. CASE REPORT: A 42-year-old African-American female presented complaining of mucopurulent discharge and pain in her left eye for a month. No history of trauma, contact lens wear or surgery was elicited and she admitted to chronic polysubstance abuse. A deep, paracentral stromal ulcer was present in the left cornea. The patient was hospitalized for culturing and empiric topical therapy. Toxicology screens proved positive for cocaine and heroine. Initial response to treatment was promising yet the patient discharged herself against medical advice and was lost to follow-up. Cultures were positive for Candida albicans. CONCLUSIONS: Practitioners should be familiar with the toxic effects that crack-cocaine abuse may have on ocular tissues, particularly the cornea. This case demonstrated the value of hospitalization, toxicology screenings and cultures in the management of the atypical keratopathy associated with substance abuse, specifically that of crack cocaine use. Corneal epithelial disruption and stromal ulceration without a history of contact lens wear, trauma, surgery, predisposing keratopathy or immunodeficiency warrants thorough investigation of patient social habits, including substance abuse. 相似文献
737.
J.L. Gordon T.F. Duffield T.H. Herdt D.F. Kelton L. Neuder S.J. LeBlanc 《Journal of dairy science》2017,100(4):2954-2966
The objective of this study was to determine the effects of butaphosphan-cyanocobalamin (B+C), glargine insulin, and propylene glycol on resolution of ketosis and average daily milk yield after treatment. Cows from 16 herds in Ontario, Canada, and 1 herd in Michigan were tested at weekly intervals between 3 and 16 DIM. Ketosis was defined as blood β-hydroxybutyrate (BHB) ≥1.2 mmol/L. All ketotic cows were given a baseline treatment of 3 d of 300 g of propylene glycol orally. Animals were then randomly assigned to treatment with 3 doses of either 25 mL of B+C or 25 mL of saline placebo and 1 dose of either 2 mL (200 IU) of glargine insulin or 2 mL of saline placebo in a 2 × 2 factorial arrangement. Outcomes of interest on all farms were ketosis cure (blood BHB <1.2 mmol/L 1 wk postenrollment), maintenance of ketosis cure (blood BHB <1.2 mmol/L 1 and 2 wk postenrollment), and blood BHB concentrations at 1 and 2 wk postenrollment. Milk weights were collected daily in 1 large freestall herd. Repeated measures ANOVA was used to evaluate blood BHB concentrations 2 wk after treatment and milk production for 30 d after treatment. Poisson regression was used to examine the effect of treatment on cure and maintenance of cure. Due to a regulatory delay causing temporary unavailability of B+C in Canada, data were analyzed in 2 sets of models: one for insulin and the corresponding placebo (n = 620) and one for the full trial (n = 380). Animals with blood glucose concentrations ≤2.2 mmol/L at the time of ketosis diagnosis were 2.1 times more likely (95% CI = 1.2 to 3.7) to be cured if treated with B+C. Animals in lactation 3 or higher that had blood glucose concentrations <2.2 mmol/L at enrollment produced 4.2 kg/d (95% CI = 1.4 to 7.1) more milk if treated with insulin versus placebo and 2.8 kg/d (95% CI = 0.9 to 4.7) more milk if treated with B+C versus placebo. Animals in lactation 3 or higher with blood glucose ≥2.2 mmol/L that were treated with insulin produced 2.3 kg/d (95% CI = 0.3 to 4.4) less milk than untreated controls. No interaction was observed between treatments. This evidence suggests that B+C and insulin may be beneficial for ketosis treatment in animals with blood glucose <2.2 mmol/L at ketosis diagnosis. It also suggests that blood glucose concentration may be an important predictor of success of ketosis treatment. 相似文献
738.
Jill H.Y. Law Author Vitae Author Vitae 《Integration, the VLSI Journal》2008,41(2):306-316
In this paper, the problem of bus-driven floorplanning is addressed. Given a set of blocks and bus specifications (the width of each bus and the blocks that the bus need to go through), we will generate a floorplan solution such that all the buses go through their blocks, with the area of the floorplan and the total area of the buses minimized. The approach proposed is based on a simulated annealing framework. Using the sequence pair representation, we derived and proved some necessary conditions for feasible buses, for which we allow 0-bend, one-bend, or two-bend. A checking will be performed to identify those buses that cannot be placed simultaneously. Finally, a solution will be generated giving the coordinates of the modules and the buses. Comparing with the results of the most updated work on this problem by Xiang et al. [Bus-driven floorplanning, in: Proceedings of IEEE International Conference on Computer-Aided Design, 2003, pp. 66-73], our algorithm can handle buses going through many blocks and the dead space of the floorplan obtained is also reduced. For example, if the buses have to go through more than 10 blocks, the approach in Xiang et al. [Bus-driven floorplanning, in: Proceedings of IEEE International Conference on Computer-Aided Design, 2003, pp. 66-73] is not able to generate any solution while our algorithm can still give solutions of good quality. 相似文献
739.
740.
Johnston CT Agnew SF Schoonover JR Kenney JW Page B Osborn J Corbin R 《Environmental science & technology》2002,36(11):2451-2458
The chemistry of concentrated sodium aluminate solutions stored in many of the large, underground storage tanks containing high-level waste (HLW) at the Hanford and Savannah River Nuclear Reservations is an area of recent research interest. Not only is the presence of aluminate in solution important for continued safe storage of these wastes, the nature of both solid and solution aluminum oxyhydroxides is important for waste pretreatment. Moreover, for many tanks that have leaked high aluminum waste in the past, little is known about the speciation of Al in the soil. In this study, Raman spectroscopy has been used to investigate the speciation of the aqueous species in the Al2O3-Na2O-H2O system over a wide range of solution compositions and hydration. A ternary phase diagram has been used to correlate the observed changes in the spectra with the composition of the solution and with dimerization of aluminate that occurs at elevated aluminate concentrations (>1.5 M). Dimerization is evidenced by growth of new Al-O stretching bands at 535 and 695 cm(-1) at the expense of the aluminate monomer band at 620 cm(-1). The spectrum of water was strongly influenced by the high concentrations of Na+ and OH- (>17 M). Upon increasing the concentration of NaOH in solution, the delta-(H-O-H) bending band of water (v2 mode) increased in frequency to 1663 cm(-1), indicating that the water contained in the concentrated caustic solution was more strongly hydrogen bonded at the higher base content. In addition, the sharp, well-resolved band at 3610 cm(-1), assigned to the v(O-H) of free OH-, increased in intensity with increasing NaOH. Analysis of the v(O-H) bands in the 3800-2600 cm(-1) region supported the overall increase in hydrogen bonding as evidenced by the increase in relative intensity of a strongly hydrated water band at 3118 cm(-1). Taking into consideration the activity of water, the molar concentrations of the monomeric and dimeric aluminate species were estimated using the relative intensities of the Al-O stretching bands from the Raman spectra. A constant apparent log Kdimer value was obtained at aluminate concentrations >1.5 M with a value of 0.97+/-0.04 at approximately 25 degrees C. This study represents the first spectral-based estimation of a thermodynamic equilibrium constant for the Al2O3-Na2O-H2O system. 相似文献