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161.
Land use changes threaten agricultural land. If agricultural land is going to be preserved, the social and economic causes
of conversion must be understood. However, analyzing the causes of agricultural conversion is complex because trends need
to be documented before analyzing the causes. One of the leading uses of agricultural land is for residential purposes. This
paper projects residential development in a Hudson River Valley watershed within Dutchess County in New York State using an
integrated modeling framework consisting of an econometric model, a geographic information system (GIS), and Monte Carlo simulation.
The econometric model is used to project residential development, providing parcel-specific probabilities of residential development.
The GIS is employed to extract socio-economic and county-level tax parcel data to be used in conjunction with bio-geophysical
attributes, such as slope, soil, and location, to calculate and project growth trends on a residential level for undeveloped
land parcels. Monte Carlo simulation is used to distribute these projections into the GIS to display outcomes of scenario
analyses to provide policy-makers a demonstration of how policies would likely affect the agricultural landscape of the watershed.
John M. Polimeni is an Assistant Professor of Economics in the Department of Humanities and Social Sciences at the Albany College of Pharmacy
in Albany, New York. Dr. Polimeni received a PhD in Ecological Economics and a BS in Mathematics at Rensselaer Polytechnic
Institute. His professional interests include: quantitative economics, spatial and regional economics, land use change, economic
development, and graduate education in Ecological Economics. He is currently working on linking ecological economics with
the laws of thermodynamics and neuroeconomics into one unified model. 相似文献
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Responses of the two‐spotted oak buprestid,Agrilus biguttatus (Coleoptera: Buprestidae), to host tree volatiles 下载免费PDF全文
165.
Jean K. Frazho DVM John Graham MVB MSC DVR Diplomate ACVR & ECVDI Jeffrey N. Peck DVM Diplomate ACVS Jacek J. De Haan DVM Diplomate ACVS & ECVS 《Veterinary surgery : VS》2010,39(7):829-832
Objective: To determine if a secondary center of ossification (SCO) of the anconeal process is present in skeletally immature dogs that do not develop an ununited anconeal process (UAP). Study Design: Case series. Animals: Dogs 77–154 days of age with conditions other than developmental disease of the elbow (n=78 dogs; total elbows=100). Methods: Mediolateral radiographic projections of the elbow were reviewed for presence or absence of a SCO of the anconeal process. Results: A SCO was radiographically evident in 16% of elbows from breeds that have been reported to be affected by UAP. The appearance of the SCO was different to an UAP fragment. None of the elbows with SCO of the anconeal process developed UAP. A SCO was not present in any small breed dogs. Conclusions: A SCO of the anconeal process is uncommon in medium and large breed dogs and the presence of a SCO does not indicate that UAP will develop. Clinical Relevance: Because radiographic diagnosis of a SCO of the anconeal process and UAP lesions have distinct appearances, an earlier diagnosis of UAP is possible. 相似文献
166.
The clinical expression and emergence of porcine circovirus 2 总被引:12,自引:0,他引:12
Harding JC 《Veterinary microbiology》2004,98(2):131-135
Since its discovery and characterization in western Canada in 1995, the distribution of post-weaning multisystemic wasting syndrome (PMWS) has grown and the syndrome is undoubtedly recognized worldwide. More recently, there is a heightened interest in several potentially related conditions including porcine dermatitis and nephropathy syndrome (PDNS), proliferative and necrotizing pneumonia (PNP), congenital tremors (CT-AII), perinatal myocarditis and reproductive failure. Although the causality of porcine circovirus type 2 (PCV2) has recently been proven [Vet. Pathol. 37 (2000) 254; J. Comp. Pathol. 122 (2000) 9; J. Vet. Diagn. Invest. 13 (2001) 185], PCV2 is present in both diseased and healthy pig populations. Furthermore, recent serologic studies have shown that there are no significant differences in PCV2 specific IgG titres between PMWS clinical and non-clinical herds (Harding et al., in press). Clearly, the transmission, epidemiology, and factors triggering clinical expression are poorly understood. With these uncertainties in mind, the objective of this paper is to review the clinical expression and emergence of PMWS and the potentially associated disease syndromes including PDNS. 相似文献
167.
John M. MacGregor John E. Rush Nancy J. Laste Rebecca L. Malakoff Suzanne M. Cunningham Natalie Aronow Daniel J. Hall Justin Williams Lori L. Price 《Journal of Veterinary Cardiology》2011,13(4):251-260
Hypothesis/ObjectivesTo describe the therapeutic use of pimobendan in cats, describe the patient population to which it was administered, document potential side effects and report the clinical course following administration of pimobendan in conjunction with standard heart failure therapy. It is hypothesized that cats with advanced heart disease including congestive heart failure from a variety of causes will tolerate pimobendan with a minimum of side effects when used in treatment in conjunction with a variety of other medications.Animals, materials and methodsOne hundred and seventy client owned cats with naturally occurring heart disease, one hundred and sixty four of which had congestive heart failure. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up data. Data collected included pimobendan dose, other medications administered concurrently, data collected at physical examination, presence or absence of heart failure, adverse effects, classification of heart disease, echocardiographic data and survival time. The data were analyzed for significance between the initial visit and any follow-up visits.ResultsAll cats were treated with pimobendan. The median pimobendan dose was 0.24 mg/kg q 12 h. Pimobendan was used in combination with multiple concurrent medications including angiotensin converting enzyme inhibitors, diuretics and anti-thrombotics. Five cats (3.0%) had potential side effects associated with pimobendan. One cat (0.6%) had presumed side effects severe enough to discontinue pimobendan use. Median survival time for 164 cats with congestive heart failure after initiation of pimobendan was 151 days (range 1–870).ConclusionPimobendan appears to be well tolerated in cats with advanced heart disease when used with a variety of concurrent medications. Randomized controlled studies need to be performed to accurately assess whether it is efficacious for treatment of congestive heart failure in cats. 相似文献
168.
Scrapie is a natural transmissible spongiform encephalopathy (TSE) of sheep, infecting the animal via the gastrointestinal tract or the skin. This project tested the hypotheses that lymph-borne cells (especially dendritic cells) are crucial for the systemic dissemination of the infectious agent from the site of infection in the skin, that PrP genotype affects PrPSC association with dendritic cells and that PrPSC carriage by cells affects their expression of cytokines. Skin, of scrapie-susceptible VRQ/ARR and scrapie-resistant ARR/ARR PrP genotypes, was scarified with FITC-labelled PrPSC. Pseudoafferent lymphatic cannulation was then used to monitor the presence of FITC-PrPSC over time in different lymph cell populations and plasma in the draining afferent lymphatics. The major observation was that PrPSC did not associate significantly with any lymphocyte or dendritic cell population in the 5 days following PrPSC scarification. The only cells seen to associate with PrPSC were neutrophils. Furthermore, despite the quantity of PrPSC used for scarification being equivalent to a standard infectious dose (the VRQ/ARR sheep dying at approximately 260 days) the only PrP found in afferent lymph during the 0-5-day period was proteinase K sensitive (i.e. soluble PrPC). No differences were observed between the PrP genotypes. Analysis of the effects of PrPSC scarification of cellular cytokine mRNA expression (by a nuclease protection assay) showed raised levels of IL-1beta and IL-8 in the susceptible VRQ/ARR group and raised levels of IFNgamma in the resistant ARR/ARR animals. 相似文献
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The degradation of pirimiphos-methyl on grains stored at moisture contents of ≈ 13 and ≈20% has been investigated. Wheat and rice grains were sprayed with [14C]- pirimiphos-methyl and stored at 20°C under controlled humidity conditions for periods of 12 and 24 weeks. At a moisture content of 13%, degradation was slow, so that at least 70% of the radioactive residue was unchanged pirimiphos-methyl after 24 weeks. Faster degradation occurred at 20% moisture content, but the major component of the radioactive residue (at least 52%) was still unchanged pirimiphos-methyl after 24 weeks. Two major degradation products were formed on the grains; one (18–23.4% of the residue) was characterised as 2-diethylamino-6-methyl-pyrimidin-4-ol, and the other (1.0–9.7% of the residue) was converted to the first by acid hydrolysis. In addition, trace amounts of O-2-ethylamino-6-methyl-pyrimidin-4-yl OO-dimethyl phosphorothioate, 2-ethylamino-6-methyl-pyrimidin-4-ol, 2- amino-6-methyl-pyrimidin-4-ol and an unidentified compound were also detected. 相似文献