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91.
This study aims at exploring the technical efficiency of lumber industry in northwestern Ontario,Canada using data envelopment analysis(DEA).The DEA model analyzes relative technical efficiency of lumber mills with disproportionate inputs and outputs by dividing the 10year time series data,for inputs and outputs of 24 lumber mills,over two periods(1999-2003 and 2004-2008).Four inputs,namely,material(log volume),labour(man-hours),two types of energy(hog-fuel and electricity),and one output(lumber volume) are used in this study.The trend analysis shows an annual reduction of 10%,13% and 13% for lumber output,log consumption(input) and number of employees,respectively,during the period 1999-2008.The results from DEA with two scenarios with energy inputs and without energy inputs,for the two periods are found to be mixed and interesting.While some mills have improved their performance in terms of best use of available scarce inputs in the second period,some have shown negative per cent change in efficiency.In the with energy input and the without energy input scenario,some of the mills show a reduction in efficiency in the second period from the first period,with the highest estimated reductions of-13.9% and-47.6%,respectively.A possible explanation for these negative performances of mills in the latter period is the decline in production in the second period compared to the first period,where these mills were not able to adjust their inputs(mostly labour) as proportional lay-offs might not have been possible.These results provide policy makers and industry stakeholders with an improved understanding of the trends of efficiency and employment as well as reallocation opportunities of future inputs in order to increase benefits from this sector. 相似文献
92.
Margaux Marclay Ingeborg M. Langohr Frederic P. Gaschen Aline Rodrigues-Hoffmann Mariano Carossino Mathew A. Stewart Alexandra N. Myers Amy M. Grooters 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(5):2091-2095
A 7-year-old castrated male French Bulldog was examined for chronic large intestinal enteropathy. A colonic mass and thickened rectal mucosa were identified, and histopathologic examination of endoscopic biopsy specimens disclosed eosinophilic proctitis with large (5-20 μm), irregularly shaped, pauciseptate hyphae that were Gomori methenamine silver and periodic acid-Schiff positive. Amplification and sequencing of ribosomal DNA extracted from paraffin-embedded tissues yielded a sequence with 97% identity to GenBank sequences for Basidiobolus ranarum. After itraconazole, terbinafine, and prednisone administration, clinical signs resolved rapidly, and sonographic lesions were largely absent after 6 weeks. Treatment was discontinued by the owner 15 weeks after diagnosis. Three weeks later, the dog collapsed acutely and was euthanized. Necropsy identified metastatic islet cell carcinoma and grossly unremarkable colorectal tissues. However, histopathology of the rectum disclosed multifocal submucosal granulomas with intralesional hyphae morphologically similar to those previously observed. This report is the first to describe medical treatment of gastrointestinal basidiobolomycosis in a dog. 相似文献
93.
94.
K. Krishnamoorthy Thomas Mathew 《Journal of Agricultural, Biological & Environmental Statistics》2002,7(3):440-451
A one-way random effects model is considered for the log-transformed shift-long personal exposure measurements, where the random effect in the model represents an effect due to the worker. Following a previous approach, we address a hypothesis-testingproblem involving the proportion of workers for whom the mean exposure exceeds the occupational exposure limit. A confidence interval is constructed for the relevant parameter of interest, following the idea of a previously presented generalized confidence interval. The confidence bound is used for the purpose of testing hypotheses, and the performance of the test is numerically in vestigated. It turns out that the test exhibits satisfactory performance regardless of the sample size, in particular, for small samples. A similar procedure is then employed for testing hypotheses concerning the overall mean exposure. The results are illustrated using examples. 相似文献
95.
Anthony Lynn Shilpa Mathew Chris T. Moore Jean Russell Emma Robinson Vithleem Soumpasi Margo E. Barker 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(2):122-127
Tart cherries are a particularly rich source of anthocyanins. Evidence indicates that dietary intake of anthocyanins is inversely associated with arterial stiffness. We conducted an open-label randomised placebo controlled study to determine whether a tart cherry juice concentrate (Cherry Active®) reduced arterial stiffness, inflammation and risk markers for cardiovascular disease in 47 healthy adults (30–50 years). Participants consumed 30 ml of cherry concentrate diluted to a volume of 250 ml with water or the same volume of an energy matched control drink daily for six weeks. Measurements were taken at baseline and at the end of the intervention. There was no effect of the intervention on arterial stiffness (P?=?0.218), c-reactive protein (P?=?0.220), systolic blood pressure (P?=?0.163), diastolic blood pressure (P?=?0.121), total cholesterol (P?=?0.342) and high density lipoprotein cholesterol (P?=?0.127). At the end of the intervention, plasma antioxidant capacity (measured as the ferric reducing ability of plasma (FRAP)) was significantly higher in the intervention group than the control group (P?=?0.012). We conclude that a tart cherry juice concentrate rich in anthocyanins has no effect on arterial stiffness, c-reactive protein and risk markers for cardiovascular disease, but evokes a minor increase in antioxidant status in healthy adults. 相似文献
96.
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98.
J S Mathew S A Ewing J R Malayer J C Fox K M Kocan 《Journal of veterinary diagnostic investigation》2000,12(5):456-459
Detection of Ehrlichia canis in acutely infected and convalescent dogs is important for effective treatment and control. However, accurate detection has been difficult to achieve, in part because dogs that have been treated therapeutically often remain seropositive for extended periods. A new method, polymerase chain reaction (PCR) assay using biotinylated E. canis-specific primers (PCR-BP), was developed for detection of E. canis. Four dogs experimentally infected with E. canis by intravenous inoculation of whole blood from carrier dogs and 2 naturally infected convalescent carriers were used to compare the specificity and sensitivity of the new method with that of microscopy/blood smear evaluation, serologic test, and conventional PCR assay using E. canis-specific primers. In experimentally infected animals, infection was detected as early as 7 days post-exposure using PCR-BP. Although the 2 naturally infected dogs were positive by serologic test and PCR-BP, both were negative by conventional PCR. Results suggest that the new method is a sensitive assay for detection of E. canis infection. In addition, results were obtained more rapidly than with other PCR-based assays. 相似文献
99.
Oyagbemi AA Azeez OI Soetan KO Ajala AT Olayemi FO Oyeyemi MO 《Tropical animal health and production》2011,43(5):1015-1018
The aim of the study was to evaluate the effects of varying concentrations of ethylenediaminetetraacetic acid (EDTA) on blood
samples from White Fulani breed of cattle and West African Dwarf goat from Nigeria. Sample sizes of 20 animals were used for
both species. Different concentrations of EDTA (2, 4, 8 and 16 mg/ml) were used. The packed cell volume (PCV), red blood cell
(RBC) and haemoglobin (Hb) concentration of blood samples collected from White Fulani breed of cattle and West African Dwarf
goat into bottles containing 16 mg/ml of EDTA were significantly lower (P < 0.05) than those samples collected from the same animals into bottle containing 2 mg/ml (control). Similarly, the PCV,
RBC and Hb values of the West African Dwarf goats in bottles containing 8 mg/ml of EDTA were significantly lower than those
of the samples in the control (2 mg/ml). This study has shown that high concentration of EDTA as an anticoagulant can lead
to a false erythrocytic index especially the PCV. In collecting blood samples for evaluation of haematological parameters,
therefore, the blood volume/anticoagulant ratio must be strictly adhered to prevent error in the evaluated parameters in cattle
and goats. Taken together, there is tendency for haemolytic anaemia to occur in blood sampled at higher concentration of anticoagulants
in West African Dwarf goat than in White Fulani breed of cattle. 相似文献
100.
Differences in perceptions and knowledge of crop diseases constitute a major obstacle in farmer–researcher cooperation, which
is necessary for sustainable disease management. Farmers’ perceptions and management of crop diseases in the northern Ethiopian
Regional State of Tigrai were investigated in order to harness their knowledge in the participatory development of integrated
disease management (IDM) strategies. Knowledge of disease etiology and epidemiology, cultivar resistance, and reasons for
the cultivation of susceptible cultivars were investigated in a total of 12 tabias (towns) in ten weredas (districts). Perception of diseases involved both scientific and spiritual conceptual frameworks. Of the more than 30 crop
diseases recorded on the major crops in the region, only rusts and powdery mildews (locally called humodia) and a few root rots were considered by farmers to be important. Farmers’ awareness of other diseases was extremely low;
some highly damaging but less conspicuous diseases, such as faba bean chocolate spot and chickpea ascochyta blight (also called
humodia), were not regarded by farmers as disease but as problems caused primarily by excessive soil moisture. Considering that some
of these “unrecognized” diseases can cause complete yield loss and genetic erosion in epiphytotic years, there is an urgent
need for bringing together farmers’ and scientists’ knowledge to complement each other. Even when farmers had access to disease-resistant
or disease-tolerant cultivars, they grew susceptible local varieties because of multiple criteria including earliness, good
yield in years with low humodia severity, suitability for home consumption, market demand/quality, and low soil fertility
and land management requirements. Farmer innovation and knowledge were evident in their use of diverse disease control measures,
but these were a mixture of the “useful and the useless.” Our findings stress the necessity for extension workers and researchers
to understand and improve farmers’ knowledge of crop diseases, and farmers’ ability to observe and experiment, through the
Farmer Field School or a similar experiential learning approach. These insights about farmers’ knowledge of crop diseases
provide a basis for further collaborative maintenance of crop genetic diversity, development of germplasm, and IPM-related
research in Africa.
相似文献
Mathew M. AbangEmail: |