Geo-referenced spatiotemporal analysis of the urban citrus canker epidemic in Florida     

Gottwald TR  Sun X  Riley T  Graham JH  Ferrandino F  Taylor EL 《Phytopathology》2002,92(4):361-377

ABSTRACT Five areas in urban Miami were identified to study the spread of Xanthomonas axonopodis pv. citri to determine if the practice of removing exposed citrus trees within 38.1 m of trees affected by citrus canker was adequate to curtail further bacterial spread. To accomplish this, 18,769 trees in dooryards were surveyed, geo-referenced by differential global positioning systems (GPS), and assayed for disease severity, age of infection, citrus cultivar, location of infection in tree, and canopy size. For each tree, the date the tree became infected was estimated and used to separate trees into contiguous 30-day categories. For each area studied, distance measurements between focal trees and newly infected trees were calculated for various temporal periods of 30, 60, 90, and 120 days in duration, corresponding to intervals of inspection survey. A visual basic application was used to calculate the distances between each newly diseased tree and all prior focal trees. The nearest distance was used because it was considered the most conservative estimate possible. It is therefore likely to be an underestimate of spread but is a good estimate of the minimum possible distances of spread. For the first four 30-day periods among the five study areas, calculated maximum distances of spread ranged from 12 to 3,474 m, indicating a broad continuum of distance for bacterial spread was possible. Disease increased during the first two-thirds of the time studied and reached an asymptote due to dry conditions in the final one-third of the duration of the study. Cross correlation analysis indicated that disease was best visualized 107 days following rainstorms with wind. Analysis of regional spatial point patterns was performed temporally for each 30-day period via a modified Ripley's K-function. Spatiotemporal analyses between periods over areas larger than previously examined were accomplished via spatiotemporal semivariogram analysis. These methods in combination demonstrated rapid increases in range of spatial dependency and range of spatiotemporal dependency for all study sites. This corresponded to rapid spread of disease across the regions studied in response to rainstorms with wind followed by a "filling in" of disease on remaining noninfected susceptible trees through time by less intense rain events. A stochastic quadratization technique demonstrated that disease incidence and disease severity were not greatly affected by urban host density but were positively correlated to host susceptibility within local 0.25-km(2) quadrats.  相似文献   

仔猪产前的生长条件会影响其断奶后的生长     

黄新新  蒋云天  Tim Lundeen 《国外畜牧学(猪与禽)》2007,27(6):17-18

1产前的影响因素加拿大Alberta大学的George R Foxcroft博士在PIC 2007年座谈会上说,虽然产品的质量或产量是很多生产环节的核心问题,但养猪业应"停止追求仔猪的数量转而关注其质量"。  相似文献   

Use of quantitative real-time PCR to determine the local inflammatory response in the intestinal mucosa and muscularis of horses undergoing small intestinal resection     

Zofia M. Lisowski  Lucas Lefevre  Tim S. Mair  Emily L. Clark  Neil P. H. Hudson  David A. Hume  R. Scott Pirie 《Equine veterinary journal》2022,54(1):52-62

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The increasing risk of Lyme disease in Canada     

Catherine Bouchard  Erin Leonard  Jules Konan Koffi  Yann Pelcat  Andrew Peregrine  Neil Chilton  Kateryn Rochon  Tim Lysyk  L. Robbin Lindsay  Nicholas Hume Ogden 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(7):693-699

There is an increasing risk of Lyme disease in Canada due to range expansion of the tick vector, Ixodes scapularis. The objectives of this article are to i) raise public awareness with the help of veterinarians on the emerging and expanding risk of Lyme disease across Canada, ii) review the key clinical features of Lyme disease in dogs, and iii) provide recommendations for veterinarians on the management of Lyme disease in dogs.  相似文献   

Review: The role of antibodies,autoantigens and food allergens in canine atopic dermatitis          下载免费PDF全文

Cherie M. Pucheu‐Haston  Petra Bizikova  Melissa N. C. Eisenschenk  Domenico Santoro  Tim Nuttall  Rosanna Marsella 《Veterinary dermatology》2015,26(2):115-e30

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Review: Lymphocytes,cytokines, chemokines and the T‐helper 1–T‐helper 2 balance in canine atopic dermatitis          下载免费PDF全文

Cherie M. Pucheu‐Haston  Petra Bizikova  Rosanna Marsella  Domenico Santoro  Tim Nuttall  Melissa N. C. Eisenschenk 《Veterinary dermatology》2015,26(2):124-e32

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A preliminary survey of the histopathological features of skin from the planum nasale and adjacent skin of dogs unaffected by dermatological or respiratory disease          下载免费PDF全文

John H. C. Hutt  Karen A. Dunn  Tim J. Scase  Michael A. Shipstone 《Veterinary dermatology》2015,26(5):359-e79

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The impact of a community-based food skills intervention on cooking confidence, food preparation methods and dietary choices - an exploratory trial     

Wrieden WL  Anderson AS  Longbottom PJ  Valentine K  Stead M  Caraher M  Lang T  Gray B  Dowler E 《Public health nutrition》2007,10(2):203-211

OBJECTIVE: To evaluate the feasibility of undertaking a food skills intervention study in areas of social deprivation aimed at altering cooking confidence, food preparation methods and dietary choices. DESIGN: A standardised skills programme was implemented in community-based settings. Pre- (T1) and post-intervention (T2) and 6-month follow-up (T3) measures (7-day diaries and self-administered questionnaires) were undertaken in intervention and comparison groups. SETTING: Eight urban communities in Scotland. SUBJECTS: One hundred and thirteen adults living in areas of social deprivation. RESULTS: It was clear that many subjects led fragmented lives and found commitment to intervention classes problematic. Sixty-three subjects completed the final (T3) assessments. The response to each component varied due to inability to attend sessions, illness, study requirements, employment, moving out of the area, change in circumstances, loss of interest and loss of postal questionnaires. At baseline, reported consumption of fruit and vegetables was low (mean frequency 8.1 +/- 4.78 times per week). Fruit intake increased significantly (P < 0.05) between T1 and T2 in the intervention group (1.7 +/- 2.36 to 2.7 +/- 3.28 times per week) only. Between T1 and T3, there was a significant increase (P < 0.05) in intervention subjects who reported confidence in following a recipe (67-90%,). CONCLUSIONS: This exploratory trial shows that a food skills intervention is likely to have a small but positive effect on food choice and confidence in food preparation. A full-scale randomised controlled trial in this hard-to-reach group would require a range of flexible approaches rather than a fully defined intervention, and presents challenges for trial design.  相似文献   

Structure and Management Issues of the Emerging Ornamental Fish Trade In Eritrea     

Tim M. Daw  Ginny C.C. Rogers  Paul Mapson  Jo E. Kynoch 《Aquarium Sciences and Conservation》2001,3(1-3):53-64

Following independence from Ethiopia in 1993, Eritrea resumed exploiting Red Sea and Arabian fish species for the ornamental trade in 1995 as a means to earn foreign exchange from sparsely exploited marine resources. This paper describes the findings of research conducted in 1997, in collaboration with the Eritrean Ministry of Fisheries. The capture, transport and export of aquarium fish were reviewed and potential impacts and the status of management were investigated through liaison with stakeholders and researchers. From 1995 to 1997 two companies exported approximately 60,000 fish per year, mainly to the USA, worth US$65,000 (export value). Seventy-five species (from 22 families) were exported. Damselfishes made up two-thirds of total exports but more valuable families (angelfishes and butterflyfishes) were more economically significant. To earn revenue for Eritrea, a 20% export tax was imposed, although this was calculated from declarations by the operators. The emerging nature of the trade allowed detailed monitoring by the Ministry of Fisheries. However, management efforts were constrained by a lack of capacity for enforcement and baseline research. Several potential effects of the trade exist but other, land-based impacts may be more pressing concerns for Eritrea's reefs. Research priorities for management are discussed as well as the implications of mariculture of Eritrean species by other nations.  相似文献   

Extramedullary plasmacytoma in the lung of a Doberman pinscher dog     

Lauren Adelman  Victoria Larson  Thomas Sissener  Tim Spotswood 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(1):1237-1240

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