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51.
Sarah J. Converse Kevin J. Shelley Steve Morey Jeffrey Chan Andrea LaTier Carolyn Scafidi Deborah T. Crouse Michael C. Runge 《Biological conservation》2011,(1):319-329
The resources available to support conservation work, whether time or money, are limited. Decision makers need methods to help them identify the optimal allocation of limited resources to meet conservation goals, and decision analysis is uniquely suited to assist with the development of such methods. In recent years, a number of case studies have been described that examine optimal conservation decisions under fiscal constraints; here we develop methods to look at other types of constraints, including limited staff and regulatory deadlines. In the US, Section Seven consultation, an important component of protection under the federal Endangered Species Act, requires that federal agencies overseeing projects consult with federal biologists to avoid jeopardizing species. A benefit of consultation is negotiation of project modifications that lessen impacts on species, so staff time allocated to consultation supports conservation. However, some offices have experienced declining staff, potentially reducing the efficacy of consultation. This is true of the US Fish and Wildlife Service’s Washington Fish and Wildlife Office (WFWO) and its consultation work on federally-threatened bull trout (Salvelinus confluentus). To improve effectiveness, WFWO managers needed a tool to help allocate this work to maximize conservation benefits. We used a decision-analytic approach to score projects based on the value of staff time investment, and then identified an optimal decision rule for how scored projects would be allocated across bins, where projects in different bins received different time investments. We found that, given current staff, the optimal decision rule placed 80% of informal consultations (those where expected effects are beneficial, insignificant, or discountable) in a short bin where they would be completed without negotiating changes. The remaining 20% would be placed in a long bin, warranting an investment of seven days, including time for negotiation. For formal consultations (those where expected effects are significant), 82% of projects would be placed in a long bin, with an average time investment of 15 days. The WFWO is using this decision-support tool to help allocate staff time. Because workload allocation decisions are iterative, we describe a monitoring plan designed to increase the tool’s efficacy over time. This work has general application beyond Section Seven consultation, in that it provides a framework for efficient investment of staff time in conservation when such time is limited and when regulatory deadlines prevent an unconstrained approach. 相似文献
52.
The purpose of this work was to study two key parameters of the lipid phase that influence flavor release-lipid level and lipid type-and to relate the results to a mass balance partition coefficient-based mathematical model. Release of 10 volatile compounds from milk-based emulsions at 10, 25, and 50 degrees C was monitored by 1-min headspace sampling with a solid-phase microextraction fiber, followed by GC-MS analysis. As compared to the observations for milk fat, changing to a lipophilic lipid (medium-chain triglycerides, MCT) and adding a monoglyceride-based surfactant did not influence the volatiles release. However, increasing the solid fat content was found to increase the release. At 25 degrees C, and even more so at 10 degrees C, concurrent with an increase in their solid fat content, hydrogenated palm fat emulsions showed increased flavor release over that observed for emulsions made with coconut oil, coconut oil with surfactant, milk fat, and MCT. However, at 50 degrees C, when hydrogenated palm fat emulsions had zero solid fat content, there was no difference in flavor release from that observed for milk fat emulsions. Varying milk fat at nine levels between 0 and 4.5% showed a systematic dependence of the release on the lipid level, dependent on compound lipophilicity. Close correlations were found between the experimental and model predictions with lipid level and percent liquid lipid as variables. 相似文献
53.
Witch flounder Glyptocephalus cynoglossus has recently been identified as a candidate species for aquaculture in the northeastern United States and the Canadian Atlantic Provinces. This study investigated the optimal temperatures for witch flounder larval first feeding and for long term larval culture from hatching through metamorphosis. Maximum first feeding occurred between 15.0 and 16.2 C. Larvae did not survive beyond first feeding when reared at mean temperatures of 5.1, 10.4, or 19.5 C and were unable to initiate feeding at mean rearing temperatures below 6.0 C. At a rearing temperature of 15.0 C in 16-L tanks, mean larval survival to 60 days post hatch (dph) was 14.1%. Mean overall length-specific growth rate for larvae reared to 60 dph at 15.0 C was 3.5%/d and mean absolute growth was 0.62 mm/d. Subsequent larval growth at 15.6 C began to taper off towards 70 dph at the onset of weaning which overlapped with larval metamorphosis. Growth plateaued at 85 dph, followed by a rebound between 90 and 95 dph. Survival was 100% when weaning onto a dry, pelleted diet was initiated at 70 dph with a 10-d live diet co-feeding period. These results are favorable and encourage the further pursuit of commercial witch flounder culture. 相似文献
54.
55.
Elizabeth B Steeves Brian J Chelack Edward G Clark Deborah M Haines 《Journal of veterinary diagnostic investigation》2002,14(1):53-56
In this study, 50 cases of canine pemphigus foliaceus and 49 cases of canine superficial pyoderma were examined by immunohistochemical staining for patterns of desmoglein expression. In 31/50 (62%) of pemphigus foliaceus cases, there was an altered staining pattern for desmoglein consisting of distinct clumped deposits at the periphery of keratinocytes and/or dark cytoplasmic staining of acantholytic cells (consistent with internalization of desmoglein). In contrast, desmoglein staining in biopsies from cases of superficial pyoderma was diffusely pale without evidence for clumping or distinct internalization. This study demonstrates that epidermal desmoglein expression is altered in some cases of pemphigus foliaceus in dogs and suggests that immunohistochemical staining for this protein may be useful in diagnosis. 相似文献
56.
David Ruslander Antony S. Moore BVSc MVSc John M. Gliatto Deborah L'Heureux Susan M. Cotter 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(4):299-301
Cytosine arabinoside (AraC) was administered as a continuous IV infusion to 15 dogs with malignant lymphoma at a dose of 300 mg/m2 /d for 2 consecutive days. Dogs were re-examined 7 d after treatment for response to therapy and for hematologic toxicity. Regardless of response, all dogs were started on combination chemotherapy at this time. Other toxicities were reported by owners. No dog responded objectively to Ara-C treatment, although 1 dog with circulating lymphoblasts had partial regression of lymphadenopathy but persistent blastemia. Thrombocytopenia (platelet count < 200,000/μL) 7 days posttreatment was the most commonly encountered hematologic toxicity, occurring in 10 of 14 dogs. Three of these 10 dogs were also mildly neutropenic (neutrophil counts of 2000 to 3000 cell/μL). Nonhematologic toxicity occurred in 8 of 15 dogs and was principally gastrointestinal in nature and mild in severity. Cytosine arabinoside at a dose of 300 mg/m2 /day was not considered an active drug for the induction of remission in dogs with lymphoma. 相似文献
57.
Cisplatin Therapy in 41 Dogs With Malignant Tumors 总被引:3,自引:0,他引:3
Deborah W. Knapp DVM Ralph C. Richardson DVM Patty L. Bonney BS RVT Kevin Hahn DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1988,2(1):41-46
Forty-one dogs with a variety of histopathologically diagnosed, measurable tumors were treated with cisplatin (cis-diamminedichloroplatinum, Platinol, Bristol Laboratories, Syracuse, NY 13221-4755) as a single agent at a dosage of 60 mg/m2 given intravenously at 3-week intervals. In an attempt to avoid renal toxicity of cisplatin, saline diuresis was induced and maintained for 4 hours before and 2 hours following cisplatin administration. The dogs received one to ten doses of cisplatin. To determine response to therapy and to monitor toxicity of the drug, the dogs were evaluated with physical examinations including tumor measurements, radiography, complete blood counts, platelet counts, urinalyses, serum urea nitrogen concentrations, and serum creatinine concentrations. An overall response rate of 19% was observed. Complete remission occurred in one of 11 dogs with squamous cell carcinomas and one of one dog with a mediastinal undifferentiated carcinoma. Partial remissions were documented in one of 11 dogs with squamous cell carcinomas, two of three dogs with metastatic osteosarcomas, one of three dogs with nasal adenocarcinomas, and one of one dog with a thyroid adenocarcinoma. Toxic side effects were primarily gastrointestinal in nature, with vomiting occurring 1-6 hours after cisplatin administration in 27 of 41 dogs. Severe anorexia occurred in three dogs, and hemorrhagic diarrhea was observed in one dog. One dog developed grand mal seizures and died 3 hours following therapy. Granulocytopenia was documented in six dogs, and thrombocytopenia was observed in four dogs. One dog showed an increase in serum urea nitrogen and creatinine concentrations, but this patient had known pre-existing renal disease.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
Davis DG Schaefer DM Hinchcliff KW Wellman ML Willet VE Fletcher JM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(1):93-96
Hypogammaglobulinemia as a result of failure of transfer of passive immunity (FTPI) is an important risk factor for infectious disease in neonatal foals. The current gold standard for determining serum immunoglobulin concentrations is radial immunodiffusion (RID). The purpose of this study was to compare immunoglobulin concentrations measured by RID with those determined by an automated turbidimetric immunoassay (TIA), which has a much shorter turnaround time. Immunoglobulin concentrations were measured by both RID and TIA in serum collected from 84 neonatal foals. Sixty-seven foals had results within the linear range for both assays. Sensitivity and specificity of TIA for diagnosis of FTPI with IgG < or = 800 mg/dL were 0.81 (95% CI 0.70-0.88) and 0.86 (95% CI 0.76-0.93) and with IgG < or = 400 mg/dL were 0.63 (95% CI 0.35-0.86) and 0.92 (95% CI 0.87-0.95), respectively. A significant linear relationship was found between IgG concentrations determined by TIA and RID (TIA = 0.9511RID + 8.4354; R2 = .59, P < .0001). The coefficients of variation for between-run and within-run precision for the TIA were 2.5 and 3%, respectively. Storage of samples from 10 foals at -20 degrees C for 10-12 months resulted in a reduction in TIA-measured serum IgG concentration of -17.6% (SD = 3.7%), indicating that long-term storage of samples at -20 degrees C should be avoided. The results of this study indicate that measurement of serum IgG by TIA can be used to evaluate foals for FTPI. 相似文献
59.
60.
Campylobacter 总被引:5,自引:0,他引:5
Moore JE Corcoran D Dooley JS Fanning S Lucey B Matsuda M McDowell DA Mégraud F Millar BC O'Mahony R O'Riordan L O'Rourke M Rao JR Rooney PJ Sails A Whyte P 《Veterinary research》2005,36(3):351-382
Species within the genus, Campylobacter, have emerged over the last three decades as significant clinical pathogens, particularly of human public health concern, where the majority of acute bacterial enteritis in the Western world is due to these organisms. Of particular concern are the species, C. jejuni and C. coli, which are responsible for most of these gastrointestinal-related infections. Although these organisms have already emerged as causative agents of zoonoses, several aspects of their epidemiology and pathophysiology are only beginning to emerge. Trends in increasing antibiotic resistance are beginning to emerge with oral antibiotics, which may be the drug of choice for when it is necessary to intervene chemotherapeutically. This review wishes to examine (i) emerging clinical aspects of the disease, such as Guillain Barre syndrome (GBS), (ii) the association between these organisms and poultry as a natural host, (iii) environmental aspects of Campylobacter epidemiology, (iv) the emergence of atypical campylobacters (v) emerging trends in antibiotic resistance, (vi) adoption of modern methods for the detection of campylobacters. 相似文献