Campylobacter in poultry: filling an ecological niche     

Lee MD  Newell DG 《Avian diseases》2006,50(1):1-9

Epidemiological studies indicate that Campylobacter species may be responsible for the majority of cases of sporadic gastroenteritis in humans. These studies also suggest that poultry may be one of the most common sources of the bacteria for humans. Campylobacter and related genera in the family Campylobacteraceae are oral and intestinal commensals of vertebrates and some nonvertebrates, a characteristic that complicates rational approaches to controlling Campylobacter contamination of poultry. This review will discuss the phylogeny, genomics, and physiology of campylobacters with the intention of revealing how these organisms have evolved to fill their intestinal ecological niche in poultry and how their physiology must be understood in order to enact effective control strategies.  相似文献   

Science and government. Navigating the anthropocene: improving Earth system governance     

Biermann F  Abbott K  Andresen S  Bäckstrand K  Bernstein S  Betsill MM  Bulkeley H  Cashore B  Clapp J  Folke C  Gupta A  Gupta J  Haas PM  Jordan A  Kanie N  Kluvánková-Oravská T  Lebel L  Liverman D  Meadowcroft J  Mitchell RB  Newell P  Oberthür S  Olsson L  Pattberg P  Sánchez-Rodríguez R  Schroeder H  Underdal A  Vieira SC  Vogel C  Young OR  Brock A  Zondervan R 《Science (New York, N.Y.)》2012,335(6074):1306-1307

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QUANTITATIVE HEPATOBILIARY SCINTIGRAPHY IN NORMAL CATS AND IN CATS WITH EXPERIMENTAL CHOLANGIOHEPATITIS     

Susan M.  Newell  DVM  MS  John P.  Graham  MVB  MSc  Gregory D.  Roberts  DVM  MS  Pamela E.  Ginn  DVM  Ellis C.  Greiner  PhD  Amy  Cardwell  CVT  Danielle  Mauragis  CVT  Christine  Knutsen  DVM  Jay M.  Harrison  MS  Frank G.  Martin  PhD 《Veterinary radiology & ultrasound》2001,42(1):70-76

Quantitative hepatobiliary scintigraphy using 99mTc-mebrofenin was performed on eight normal cats and on the same cats after induction of experimental cholangiohepatitis by infection with the liver fluke Platynosomum concinnum. Hepatobiliary scintigraphy was performed 3 times at 10 weeks, 4 months and 6 months after infection. In addition, routine biochemical tests, hepatic ultrasound and ultrasound guided hepatic biopsy samples were obtained at the same time points, and the results compared with hepatobiliary scintigraphy. The normal hepatic extraction fraction was determined to be 85%, and the normal hepatic excretion half time (T 1/2) was 14 minutes. There was no significant change in scintigraphic parameters compared to pre-infection values at any time following infection with the liver fluke. No correlation between scintigraphic parameters and histologic scores was found; however, significant correlation was identified between parasite burden and histologic scores 6 months following infection. Despite the presence of severe multifocal histologic abnormalities, minimal clinical, biochemical and scintigraphic derangements were identified using this model of cholangiohepatitis. Based on this study, hepatobiliary scintigraphy appears to be an insensitive test for structural hepatobiliary abnormalities. The role of hepatobiliary scintigraphy in functional hepatobiliary abnormalities of the feline liver has not been determined.  相似文献   

Summer dormancy in Elymus scaber and its hybridity with wheat     

Matthew T. Newell  Richard C. Hayes  James M. Virgona  Philip J. Larkin 《Euphytica》2015,204(3):535-556

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Testing for trends when there are changes in methods     

Avis D. Newell  D. James Blick  Randy C. Hjort 《Water, air, and soil pollution》1993,67(3-4):457-468

Data from monitoring projects often include sampling or analytical changes that preclude trend analysis on the entire period of record. A modification of the nonparametric Kendall's test for monotonic trends, which accounts for such changes in the period of record, is described here. This approach blocks the data so that only data collected or analyzed under similar circumstances are compared. Alternatively, when appropriate data exist, data collected using the old method may be calibrated to values expected from the new method. Traditional trend tests may then be applied to resulting data sets. Results from simulations assessing both the power of the blocked test and the standard test performed on calibrated data are presented. The power of the blocked test exceeded the power of the calibration approach only when the calibration error was extremely large. Both the blocking and calibration approaches were applied to and compared for chemical data from Vermont lakes.  相似文献   

Who eats four or more servings of fruit and vegetables per day? Multivariate classification tree analysis of data from the 1998 Survey of Lifestyle, Attitudes and Nutrition in the Republic of Ireland     

Friel S  Newell J  Kelleher C 《Public health nutrition》2005,8(2):159-169

OBJECTIVE: To identify, using the novel application of multivariate classification trees, the socio-economic, sociodemographic and health-related lifestyle behaviour profile of adults who comply with the recommended 4 or more servings per day of fruit and vegetables. DESIGN: Cross-sectional 1998 Survey of Lifestyle, Attitudes and Nutrition. SETTING: Community-dwelling adults aged 18 years and over on the Republic of Ireland electoral register. SUBJECTS: Six thousand five hundred and thirty-nine (response rate 62%) adults responded to a self-administered postal questionnaire, including a semi-quantitative food-frequency questionnaire. RESULTS: The most important determining factor of compliance with the fruit and vegetable dietary recommendations was gender. A complex constellation of sociodemographic and socio-economic factors emerged for males whereas the important predictors of 4 or more servings of fruit and vegetable consumption among females were strongly socio-economic in nature. A separate algorithm was run to investigate the importance of health-related lifestyle and other dietary factors on compliance with the fruit and vegetable recommendations. Following an initial split on compliance with dairy recommendations, a combination of non-dietary behaviours showed a consistent pattern of healthier options more likely to lead to compliance with fruit and vegetable recommendations. There did, however, appear to be a compensatory element between the variables, particularly around smoking, suggesting the non-existence of an exclusive lifestyle for health risk. CONCLUSIONS: Material and structural influences matter very much for females in respect to compliance with fruit and vegetable recommendations. For males, while these factors are important they appear to be mediated through other more socially contextual-type factors. Recognition of the role that each of these factors plays in influencing dietary habits of men and women has implications for the manner in which dietary strategies and policies are developed and implemented.  相似文献   

Liquid chromatographic method for determination of aflatoxins B1, B2, G1, and G2 in corn and peanut products: collaborative study   总被引：1，自引：0，他引：1  

D L Park  S Nesheim  M W Trucksess  M E Stack  R F Newell 《Journal of the Association of Official Analytical Chemists》1990,73(2):260-266

A collaborative study of a liquid chromatographic method for the determination of aflatoxins B1, B2, G1, and G2 was conducted in laboratories located in the United States, Canada, South Africa, and Switzerland. Twenty-one artificially contaminated raw peanuts, peanut butter, and corn samples containing varying amounts of aflatoxins B1, B2, G1, and G2 were distributed to participating laboratories. The test portion was extracted with methanol-0.1N HCl (4 + 1), filtered, defatted with hexane, and then partitioned with methylene chloride. The concentrated extract was passed through a silica gel column. Aflatoxins B1 and G1 were derivatized with trifluoroacetic acid, and the individual aflatoxins were determined by reverse-phase liquid chromatography with fluorescence detection. Statistical analysis of the data was performed to determine or confirm outliers, and to compute repeatability and reproducibility of the method. For corn, relative standard deviations for repeatability (RSDr) for aflatoxin B1 ranged from 27.2 to 8.3% for contamination levels from 5 through 50 ng/g. For raw peanuts and peanut butter, RSDr values for aflatoxin B1 were 35.0 to 41.2% and 11.2 to 19.1%, respectively, for contamination levels from 5 through 25 ng/g. RSDr values for aflatoxins B2, G1, and G2 were similar. Relative standard deviations for reproducibility (RSDr) for aflatoxin B1 ranged from 15.8 to 38.4%, 24.4 to 33.4%, and 43.9 to 54.0% for corn, peanut butter, and raw peanuts, respectively. The method has been adopted official first action for the determination of aflatoxins B1, B2, G1, and G2 in peanut butter and corn at concentrations greater than or equal to 13 ng total aflatoxins/g.  相似文献   

The Distribution of Phosphorus in Popes Creek, VA, and in the Pocomoke River, MD: Two Watersheds with Different Land Management Practices in the Chesapeake Bay Basin     

N. S. Simon  Owen P. Bricker  Wayne Newell  John McCoy  Rijk Morawe 《Water, air, and soil pollution》2005,164(1-4):189-204

This paper compares phosphorus (P) concentrations in sediments from two watersheds, one with, and one without, intensive animal agriculture. The watersheds are in the coastal plain of the Chesapeake Bay and have similar physiographic characteristics. Agriculture in the Pocomoke River, MD, watershed supplied 2.7 percent of all broiler chickens produced in the USA in 1997. Poultry litter is an abundant, local source of manure for crops. Broiler chickens are not produced in the Popes Creek, VA, watershed and poultry manure is, therefore, not a major source of fertilizer. The largest concentrations of P in sediment samples are found in floodplain and main-stem bottom sediment in both watersheds. Concentrations of total P and P extracted with 1N HCl are significantly larger in main-stem bottom sediments from the Pocomoke River than in main-stem bottom sediments from Popes Creek. Larger concentrations of P are associated with what are potentially redox sensitive iron oxyhydroxides in sediment samples from the Pocomoke River watershed than are associated with what are potentially redox sensitive iron oxyhydroxides in sediment samples from the Popes Creek watershed. Data for P and iron (Fe) concentrations in sediments from the Popes Creek watershed provide a numerical framework (baseline) with which to compare P and Fe concentrations in sediment from the Pocomoke River watershed.  相似文献   

Mycotic rumenitis in American bison (Bison bison).     

N W Dyer  T K Newell 《Journal of veterinary diagnostic investigation》2002,14(5):414-416

Necropsies were performed on 2 American bison (Bison bison) cows, I of which died acutely and the other that died after a week of illness. Gross and microscopic lesions were consistent with severe mycotic infection of the forestomachs. Both animals had been abruptly placed on a breeder ration 1 month after calving, and had developed acidosis and subsequent fungal invasion of tissues. History and lesions in this case indicate that bison are susceptible to rumen acidosis and its sequelae.  相似文献   

Copper-Catalyzed Oxidation of Alcohols to Aldehydes and Ketones: An Efficient, Aerobic Alternative   总被引：1，自引：0，他引：1  

IE Marko  PR Giles  M Tsukazaki  SM Brown  CJ Urch 《Science (New York, N.Y.)》1996,274(5295):2044-2046

An efficient, copper-based catalyst has been discovered that oxidizes a wide range of alcohols into aldehydes and ketones under mild conditions. This catalytic system utilizes oxygen or air as the ultimate, stoichiometric oxidant, producing water as the only by-product.  相似文献