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Humeral intracondylar fissures (HIF) have been predominantly reported in spaniel breeds and proposed to be possible risk factors for humeral condyle fractures (HCF). We hypothesized that the prevalence of incidental HIF in French Bulldogs may be greater than that of other brachycephalic breeds. A retrospective, observational, prevalence study was performed using CT examinations of French bulldogs and other brachycephalic breed dogs presenting for an unrelated condition. Two European College of Veterinary Diagnostic and Imaging-certified radiologists reviewed the images of the humeral condyles of these dogs. A classification system was devised to grade the findings. We considered a Score 1 to be normal, Score 2 to have centralised sclerosis, Score 3 to have a partial fissure and Score 4 to have a complete fissure. A total of 228 elbows were reviewed from 122 dogs. Of this population, 145 elbows were from French Bulldogs, 54 were from Pugs, and the remainder were from a mix of other brachycephalic breeds. The prevalence of HIF (score 3 or 4) in elbows of the French bulldog, pug and other breed groups was 6.9% (CI 2.8–11%), 5.6% (CI 0–11.7%), and 3.4% (CI 0–10.15%), respectively. At a dog level, the prevalence of HIF (score 3 or 4 present in at least one elbow) was found to be 11.8% (CI 4.6–19%) in French Bulldogs, 11.1% (CI 0–22.9%) in Pugs, and 5.26% (CI 0–15%) in the other breed group. There was no significant difference between the breed groups. The inter-reviewer reliability for CT scoring of HIF based on Cohen's weighted kappa was low at 0.19.  相似文献   
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The economic impact of reducing the amount of nitrate leached out of the root zone under irrigation in the arid West was examined. The economic incentives of irrigation management were evaluated under the assumptions of both profit-maximizing and utility-maximizing (in reducing cost and effort expended in irrigation) decision-making criteria. The results indicate that there is a coincidence of interests of the farmer and the environment provided some leaching occurred. If no leaching is allowed, profit decreases markedly. Both behaviors result in less nitrate leaching than less profitable or less utility-producing irrigating practices.  相似文献   
4.

Context

The study of habitat fragmentation is complex because multiple, potentially synergistic, ecological processes may be acting simultaneously. Further, edge effects themselves may be complex in that additivity from multiple edges can give rise to heterogeneous nearest–edge gradients.

Objectives

We used heat diffusion as a proxy for additive edge effects in two study landscapes in order to test whether two key observations recently attributed to synergy between edge and area effects could be more simply explained by additivity; namely, steeper edge gradients in larger fragments and variation in slopes of species–area relationships as a function of distances to fragment edges.

Methods

We sampled forest structure in northwestern Madagascar at various distances from the edge in fragments and continuous forest and used an inverse modelling approach to parameterize the model. In addition, we applied the model to data from a published study of beetle communities in fragmented forests in New Zealand.

Results

With increasing proximity to edges, woody stem densities decreased and, as predicted, smaller fragments had lower stem densities and less steep edge gradients than larger ones. The model successfully predicted shifts in species–area relationships as a function of nearest–edge distances for beetle species, although observed richness for forest specialists in the smallest fragments was lower than predicted.

Conclusions

Two key observations attributed to synergy between edge and area effects were explained by edge additivity. The model is particularly useful in that it can help to disentangle the complex sets of processes acting in fragmented landscapes.
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Utilization of the major corn (Zea mays) reserve materials (free saccharides, starch, triglycerides, and zein) was monitored during infection of detached kernels by Aspergillus flavus (A. flavus) over a 12-day period. Inoculated whole kernels were compared to noninoculated kernels. Concentrations of sucrose and raffinose in inoculated seed decreased to nearly zero at 6 days, whereas concentrations of these saccharides in noninoculated seed dropped at a considerably slower rate, and significant levels remained at the end of the incubation period. Triglyceride concentrations remained unchanged in the noninoculated seed but dropped continuously after 2 days in the inoculated seed. Starch and zein concentrations did not change during the 12-day incubation period. Aflatoxin B1 was first detected after 2 days and increased to about 20 microg/g (20,000 ppb) after 12 days. Very low aflatoxin concentrations were detected in the noninoculated seed. Significant concentrations of erythritol, arabitol, and mannitol were produced during infection, with peak concentrations occurring at 8 days. Whole seed and germ tissue appeared to support good fungal growth and aflatoxin production, whereas ground tissues and endosperm did not. A. flavus preferentially utilized saccharides as initial carbon substrates followed by triglycerides. When invading nonwounded corn kernels, the fungus selectively targets the germ tissue where these materials are localized in the highest concentrations.  相似文献   
6.
In coping with increasing energy consumption and the consequential environmental pollution, green development is becoming an important part of social development. Since the inauguration of China’s Silk Road Economic Belt Initiative (BRI), economic cooperation between China and other countries along BRI has seen much growth. Therefore, it is of great significance to study the levels of green total factor productivity (GTFP) of the countries in the Silk Roads Economic Belt (B&R) and examine how these levels vary spatially and evolve temporally. In this paper, a panel regression analysis with DEA windows is used to study the spatiotemporal trends of the levels of GTFP. The results are: (1) The B&R countries have seen an increase in their overall levels of GTFP over time; (2) There are regional differences in the levels of GTFP, with higher efficiency in Western Asia and Central and Eastern Europe, and lower efficiency in Southeast and Central Asia; (3) The analysis of GTFP for countries in these regions shows that the efficiencies of most countries have been improving, with that of only a few countries have been decreasing; (4) By using regression analysis, we find that variables such as import, export, industrial structure, and urban affect the B&R countries with growing GTFP.  相似文献   
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OBJECTIVE: To compare the effect of semen extender and seminal plasma on postthaw motility and filtration through a glass wool-Sephadex (GWS) filter for frozen stallion semen. SAMPLE POPULATION: 7 stallions from which we collected > or = 3 ejaculates/stallion. PROCEDURES: 4 experiments were conducted to evaluate postthaw quality of frozen stallion semen. Kenney extender was compared with glucose-EDTA extender by use of various dilution rates that resulted in differing concentrations of seminal plasma. Stallions known to produce semen with poor postthaw quality were used to investigate whether a particular extender or dilution rate could improve ability of such semen to survive freeze-thaw procedures. RESULTS: Use of Kenney extender as the centrifugation extender significantly improved postthaw motility and GWS filtration, compared with glucose-EDTA. Extending semen at a dilution of 1:3 was significantly better than 1:1 for both motility and GWS filtration. In addition, including seminal plasma at a concentration of 5% in the cryopreserved semen resulted in significantly higher yield of spermatozoa after GWS filtration, compared with complete removal of SP or use of seminal plasma at 25%. Lastly, semen with poor postthaw quality had significantly improved postthaw quality in regard to motility and GWS filtration when semen was frozen with seminal plasma at a concentration of 5%, compared with semen frozen with seminal plasma at a concentration of 25%. CONCLUSIONS AND CLINICAL RELEVANCE: Use of Kenney extender at a high dilution (> or = 1:3) immediately after collection of semen can improve postthaw quality of frozen stallion semen.  相似文献   
10.
Zolpidem is a nonbenzodiazepine hypnotic of the imidazopyridine class that is used to treat insomnia in humans. Zolpidem binds selectively to the benzodiazepine omega-1 receptor and increases the frequency of chloride channel opening, which results in inhibition of neuronal excitation. A retrospective study was conducted of zolpidem ingestion in dogs that were reported to the ASPCA Animal Poison Control Center (APCC) between January 1998 and July 2000. Data analysis included amount ingested, clinical effects, and time of onset of signs. Thirty-three reports of zolpidem ingestion in dogs (ranging in age from 5 months to 16 years) were evaluated. Approximate ingested dosages ranged from 0.24 to 21 mg/kg. Clinical signs reported included ataxia (18 dogs; 54.5%), hyperactivity (10 dogs; 30.3%), vomiting (7 dogs; 21.2%), and lethargy (5 dogs; 15.2%), as well as panting, disorientation, nonspecific behavior disorder, and hypersalivation (4 dogs each sign; 12.1%). Other signs reported include tachycardia, tremors, apprehension, vocalization, hypersalivation, weakness, and hyperesthesia. In 85% percent of reports, clinical signs developed within 1 hour and usually resolved within 12 hours. Although central nervous system (CNS) depression is reported as a primary effect of zolpidem in humans and would also be expected in dogs, information obtained from this study indicates that some dogs may exhibit a paradoxical excitation reaction. This effect appears to vary among individual dogs.  相似文献   
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