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41.
Mishchenko MI Geogdzhayev IV Rossow WB Cairns B Carlson BE Lacis AA Liu L Travis LD 《Science (New York, N.Y.)》2007,315(5818):1543
Analysis of the long-term Global Aerosol Climatology Project data set reveals a likely decrease of the global optical thickness of tropospheric aerosols by as much as 0.03 during the period from 1991 to 2005. This recent trend mirrors the concurrent global increase in solar radiation fluxes at Earth's surface and may have contributed to recent changes in surface climate. 相似文献
42.
Daniel R. Block Michael Thompson Jill Euken Toni Liquori Frank Fear Sherill Baldwin 《Agriculture and Human Values》2008,25(3):379-388
Engagement happens when academics and non-academics form partnerships to create mutual understanding, and then take action
together. An example is the “value web” work associated with W. K. Kellogg Foundation’s Food Systems Higher Education–Community
Partnership. Partners nationally work on local food systems development by building value webs. “Value chains,” a concept
with considerable currency in the private sector, involves creating non-hierarchical relationships among otherwise disparate
actors and entities to achieve collective common goals. The value web concept is extended herein by separating the values
of the web itself, such as the value of collaboration, from values “in” the web, such as credence values associated with a
product or service. By sharing and discussing case examples of work underway around the United States, the authors make a
case for employing the value webs concept to represent a strategy for local food systems development, specifically, and for
higher education–community partnerships, generally.
Daniel R. Block is an associate professor of geography and coordinator of the Frederick Blum Neighborhood Assistance Center at Chicago State University. His current research focuses on food access issues in urban environments, particularly in Chicago. Michael Thompson is an assistant professor at Oregon State University, and a Seafood and Fisheries specialist for Oregon Sea Grant Extension. Primary areas of research include fisheries management, seafood quality/handling, and seafood product development. Jill Euken is an industrial specialist for biobased products for Iowa State University Extension/CIRAS, and deputy director, ISU Bioeconomy Institute. She was part of the steering team for the Iowa Value Chain Partnership for Sustainable Agriculture and led the Bioeconomy Working Group. Toni Liquori is a nutritionist, teacher and food activist with a long time interest in the design, implementation, and evaluation of school-based intervention programs and coalition building for activism around food related issues, as well as teaching and training in public health. Frank Fear is senior associate dean, College of Agriculture and Natural Resources; and professor, in the Department of Community, Agriculture, Recreation and Resources Studies; and Senior Outreach Fellow at Michigan State University. He is lead author of Coming to Critical Engagement (University Press of America, 2006), an analysis of the engagement movement in higher education; and recently completed two terms as president of the Greater Lansing Food Bank. Sherill Baldwin is ecology director at Mercy Center at Madison, Connecticut, a spiritual retreat and conference center. She previously provided consulting services to CitySeed, Inc. in New Haven (CT) and to Frank Fear and the W. K. Kellogg Foundation for a community learning project related to sustainable food systems. She has an MS in Resource Development from Michigan State University and a BA in Solid Waste Management from the University of Massachusetts. 相似文献
Daniel R. BlockEmail: |
Daniel R. Block is an associate professor of geography and coordinator of the Frederick Blum Neighborhood Assistance Center at Chicago State University. His current research focuses on food access issues in urban environments, particularly in Chicago. Michael Thompson is an assistant professor at Oregon State University, and a Seafood and Fisheries specialist for Oregon Sea Grant Extension. Primary areas of research include fisheries management, seafood quality/handling, and seafood product development. Jill Euken is an industrial specialist for biobased products for Iowa State University Extension/CIRAS, and deputy director, ISU Bioeconomy Institute. She was part of the steering team for the Iowa Value Chain Partnership for Sustainable Agriculture and led the Bioeconomy Working Group. Toni Liquori is a nutritionist, teacher and food activist with a long time interest in the design, implementation, and evaluation of school-based intervention programs and coalition building for activism around food related issues, as well as teaching and training in public health. Frank Fear is senior associate dean, College of Agriculture and Natural Resources; and professor, in the Department of Community, Agriculture, Recreation and Resources Studies; and Senior Outreach Fellow at Michigan State University. He is lead author of Coming to Critical Engagement (University Press of America, 2006), an analysis of the engagement movement in higher education; and recently completed two terms as president of the Greater Lansing Food Bank. Sherill Baldwin is ecology director at Mercy Center at Madison, Connecticut, a spiritual retreat and conference center. She previously provided consulting services to CitySeed, Inc. in New Haven (CT) and to Frank Fear and the W. K. Kellogg Foundation for a community learning project related to sustainable food systems. She has an MS in Resource Development from Michigan State University and a BA in Solid Waste Management from the University of Massachusetts. 相似文献
43.
44.
M A Luke H T Masumoto T Cairns H K Hundley 《Journal of the Association of Official Analytical Chemists》1988,71(2):415-433
During a 5 year period from 1982 to 1986, the FDA Los Angeles District Laboratory analyzed 19,851 samples of domestic and imported food and feed commodities for pesticide residues. A single, rapid, multiresidue method was used. The resultant data have been compiled showing the commodities sampled and the identity and range of levels of pesticide residues detected, including an indication of those residue findings that did not comply with U.S. federal tolerance levels. The residue data presented should not be viewed as being representative of the U.S. food supply; rather, the results are indicative of a surveillance- and compliance-oriented sampling of various food shipments collected by the Los Angeles District. 相似文献
45.
Hong Li Robert J. Lascano Jill Booker L. Ted Wilson Kevin F. Bronson 《Soil & Tillage Research》2001,58(3-4):245-258
Landscape variability associated with topographic features affects the spatial pattern of soil water and N redistribution, and thus N uptake and crop yield. A landscape-scale study was conducted in a center pivot irrigated field on the southern High Plains of Texas in 1999 to assess soil water, soil NO3-N, cotton (Gossypium hirsutum L.) lint yield, and N uptake variability in the landscape, and to determine the spatial correlation between these landscape variables using a state-space approach. The treatments were irrigation at 50 and 75% cotton potential evapotranspiration (ET). Neutron access tubes were placed at a 15-m interval along a 710 m (50% ET) and 820 m (75% ET) transect across the field. Soil NO3-N in early spring was autocorrelated at a distance varying between 60 and 80 m. Measured soil volumetric water content (WC), total N uptake, and lint yield were generally higher on lower landscape positions. Cotton lint yield was significantly correlated to soil WC (r=0.76), soil NO3-N (r=0.35), and site elevation (r=−0.54). Differences of site elevation between local neighboring points explained the soil water, NO3-N and lint yield variability at the micro-scale level in the landscape. Soil WC, cotton lint yield, N uptake, and clay content were crosscorrelated with site elevation across a lag distance of ±30–40 m. The state-space analysis showed that cotton lint yield was positively weighted on soil WC availability and negatively weighted on site elevation. Cotton lint yield state-space models give insights on the association of soil physical and chemical properties, lint yield, and landscape processes, and have the potential to improve water and N management at the landscape-scale. 相似文献
46.
47.
T Cairns E G Siegmund 《Journal of the Association of Official Analytical Chemists》1987,70(5):858-862
The production of a protonated molecular ion, MH+, for a pesticide under investigation is often preferred for primary identification purposes. However, the lack of fragment ions under such chemical ionization conditions can place the burden of proof on a single ion species for confirmation. Although a single ion representing the molecule at the correct retention time on a packed column or high-resolution capillary column might seem to have furnished sufficient evidence for unambiguous confirmation, in a number of cases additional specificity can improve the analytical result. With the introduction into commerce of triple stage quadrupole (TSQ) instruments, the possibility of improving the degree of specificity by chemical ionization has emerged for practical pesticide residue confirmation analysis. Use of collision-activated dissociation (CAD) experiments to form daughter ions from the protonated molecular ion of 2 representative organophosphorus pesticides has provided a second dimensional plane of characterization for confirmatory purposes at incurred residue levels. 相似文献
48.
Jill A. Richardson DVM Rachel A. Balabuszko CVT 《Journal of Veterinary Emergency and Critical Care》2001,11(1):53-58.
Objective: To summarize typical clinical signs, characterize the anticipated course of action, and give treatment recommendations for ibuprofen ingestion in ferrets.
Design: Retrospective study
Patients: Records of 43 cases of ibuprofen ingestion in ferrets that were reported between January 1996-March 2000, to the ASPCA Animal Poison Control Center (APCC).
Measurements and Main Results: Twenty-seven (93.1%) ferrets that had ingested ibuprofen developed neurologic signs, such as depression, coma, ataxia, recumbency, tremors, and weakness. In addition, 16 cases (55.2%) had one or more GI effects including anorexia, vomiting, retching or gagging, diarrhea, and melena. Polydipsia, polyuria, dysuria, renal failure, weight loss, shallow breathing, metabolic acidosis, dehydration, and hypothermia were also reported. Death was reported in 4 cases. The lowest dose associated with death was 220 mg/kg.
Conclusion: Data in this study indicate that clinical signs of ibuprofen toxicosis in ferrets are more severe than those expected at similar dosages in dogs. The reason for this difference is poorly understood since the pathophysiology of ibuprofen is relatively unknown in ferrets. The onset of clinical signs appeared to occurr soon after ingestion and the toxic effects in ferrets typically involve the CNS, GI and renal systems. Treatment for ibuprofen toxicosis in the ferret includes stabilization, gastrointestinal decontamination, fluid diuresis, GI protection, and supportive care.(J Vet Emerg Crit Care 2001; 11(1):53–59) 相似文献
Design: Retrospective study
Patients: Records of 43 cases of ibuprofen ingestion in ferrets that were reported between January 1996-March 2000, to the ASPCA Animal Poison Control Center (APCC).
Measurements and Main Results: Twenty-seven (93.1%) ferrets that had ingested ibuprofen developed neurologic signs, such as depression, coma, ataxia, recumbency, tremors, and weakness. In addition, 16 cases (55.2%) had one or more GI effects including anorexia, vomiting, retching or gagging, diarrhea, and melena. Polydipsia, polyuria, dysuria, renal failure, weight loss, shallow breathing, metabolic acidosis, dehydration, and hypothermia were also reported. Death was reported in 4 cases. The lowest dose associated with death was 220 mg/kg.
Conclusion: Data in this study indicate that clinical signs of ibuprofen toxicosis in ferrets are more severe than those expected at similar dosages in dogs. The reason for this difference is poorly understood since the pathophysiology of ibuprofen is relatively unknown in ferrets. The onset of clinical signs appeared to occurr soon after ingestion and the toxic effects in ferrets typically involve the CNS, GI and renal systems. Treatment for ibuprofen toxicosis in the ferret includes stabilization, gastrointestinal decontamination, fluid diuresis, GI protection, and supportive care.(J Vet Emerg Crit Care 2001; 11(1):53–59) 相似文献
49.
Arnold JE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(2):115-123
BACKGROUND: Standardized hematologic methods and reference intervals have not been established for cartilaginous fishes (sharks, skates, and rays) despite the large number of animals displayed in zoos and aquariums worldwide. OBJECTIVE: The focus of this study was to validate CBC methods for sandbar shark (Carcharhinus plumbeus) blood, based on criteria established in human medicine, for the following tests: RBC count, total WBC count, PCV, hemoglobin (Hgb) concentration, and WBC differential percentages. METHODS: Replicate CBCs were performed using blood samples from 5 captive sandbar sharks. Three protocols for RBC and total WBC counts were compared, as were different centrifugation times for PCV determination, and 2 methods for Hgb concentration. Means, minimum and maximum values, and CVs were compared to CAP and CLIA performance guidelines for human tests. RESULTS: Total WBC counts in a diluent modified for elasmobranch blood, Hgb concentration by the cyanmethemoglobin method after removal of nuclei, and WBC differential percentages showed acceptable performance. PCV results were acceptable when tubes were centrifuged for at least 5 minutes. Total RBC counts by all 3 methods exceeded the acceptable error for manual counts of human cells. CONCLUSIONS: Standardized CBC tests can be used as health assessment tools for elasmobranchs. Total RBC counts should be viewed as estimates. 相似文献
50.
OBJECTIVE: To compare abduction angles of shoulders with medial instability and unaffected shoulders in the same dogs and in age- and breed-matched dogs. STUDY DESIGN: Case-control study. ANIMALS: Dogs with medial instability of the shoulder (n=33) and 26 control dogs. METHODS: Dogs were sedated and positioned in lateral recumbency with both scapulas parallel to the table. With the elbow and shoulder in extension, the non-recumbent limb was maximally abducted and the angle between the scapular spine and lateral aspect of the brachium measured with a goniometer; a digital image was taken from the cranial aspect. Both techniques were performed in triplicate by 2 examiners. Mean abduction angles for each shoulder were determined from goniometric measurements and image analysis. Data were analyzed for significant differences between affected and unaffected shoulders, measurement techniques, and examiners. Strength of correlation between measurement techniques was determined. RESULTS: Mean abduction angles for shoulders with instability (53.7+/-4.7 degrees goniometric, 51.2+/-4.9 degrees image) were significantly (P<.001) larger than for all unaffected shoulders (32.6+/-2.0 degrees goniometric, 30.9+/-2.3 degrees image). In dogs diagnosed with instability, affected shoulders had significantly (P<.001) larger abduction angles than the contralateral (unaffected) shoulders. No significant differences were identified between right and left shoulders for control dogs, measurement techniques, or examiners. A strong (r=0.90) significant (P<.001) positive correlation between measurement techniques was noted. CONCLUSIONS: Shoulder abduction angles measured under sedation provide objective data for diagnosis of shoulder instability in dogs. Shoulders with clinical and arthroscopic evidence of medial instability have significantly higher abduction angles than shoulders that are considered normal. CLINICAL RELEVANCE: Determination of shoulder abduction angles should be included in the diagnostic protocol for forelimb lameness assessment in dogs. 相似文献