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131.
This study characterised the airborne mycobiota of a rice plantation in Bauta (Havana, Cuba), with a view to improving crop quality. Culturable airborne fungi were sampled between March 2007 and February 2008 using a volumetric method (SAS Super 100) with potato dextrose agar as culture medium. The total fungal count was 51,425 cfu/m3. The 39 filamentous genera identified included several major rice pathogens (Bipolaris, Curvularia, Alternaria, Pyricularia, Cercospora and Fusarium) as well as potentially mycotoxigenic species of Fusarium, Penicillium and Aspergillus. Analysis of the influence of weather-related factors on spore counts revealed that total counts and Penicillium counts correlated positively with daily relative humidity, mean temperature and dew point.  相似文献   
132.
Laser altimetry by the MESSENGER spacecraft has yielded a topographic model of the northern hemisphere of Mercury. The dynamic range of elevations is considerably smaller than those of Mars or the Moon. The most prominent feature is an extensive lowland at high northern latitudes that hosts the volcanic northern plains. Within this lowland is a broad topographic rise that experienced uplift after plains emplacement. The interior of the 1500-km-diameter Caloris impact basin has been modified so that part of the basin floor now stands higher than the rim. The elevated portion of the floor of Caloris appears to be part of a quasi-linear rise that extends for approximately half the planetary circumference at mid-latitudes. Collectively, these features imply that long-wavelength changes to Mercury's topography occurred after the earliest phases of the planet's geological history.  相似文献   
133.
The perception of Rwandan government officials, NGOs, and extension specialists about smallholder agroforestry adoption as a strategy for smallholder farmers in Rwanda was investigated using a strengths, weaknesses, opportunities, and threats analysis framework combined with the analytical hierarchy process. Results indicate that smallholder agroforestry is viewed positively as a suitable strategy for Rwandan smallholder farmers. The most important positive features were the potential for increased agricultural output from agroforestry and a favorable policy environment in Rwanda supporting sustainable agriculture. Results also indicate that there needs to be better coordination of various efforts to promote agroforestry and stronger extension services for smallholder farmers. Carbon offset markets and other environmental service markets were seen as a potential opportunity for smallholder agroforestry. However, the results also indicate that there is substantial uncertainty and skepticism concerning how such markets would benefit smallholder farmers who adopted agroforestry.  相似文献   
134.
135.
Ovar-DRB1 is one of the most important response genes in the major histocompatibility complex (MHC) class II region of sheep. Gene polymorphism in the second exon of Ovar-DRB1 in three different Iranian fat-tailed sheep breeds (Lori-Bakhtiari, Shaul and Zandi) was analyzed by either restriction fragment length polymorphisms (RFLP) or direct sequencing. A total of 92 Lori-Bakhtiari, 40 Shaul, and 47 Zandi sheep were examined. PCR-RFLP identified 17 genotypes in Lori-Bakhtiari sheep, 12 in Shaul sheep and 11 in Zandi sheep. Collectively, 24 different genotypes could be found for Iranian fat-tailed sheep. Using direct sequencing, seven new sequences in exon 2 of the Ovar-DRB1 gene were identified. Generalized linear modeling with a multinomial error structure showed that the sheep populations had significantly different allele frequencies.  相似文献   
136.
PRACTICAL RELEVANCE: Obesity is the most common unhealthy nutritional condition that is recognized in cats. Documented associated health risks include diabetes mellitus, lameness, non-allergic skin disease, feline lower urinary tract disease and idiopathic hepatic lipidosis. CLINICAL CHALLENGES: Simply recommending a diet designed for weight loss fails, in most cases, to result in successful weight loss in the obese or overweight cat. A more in-depth approach that centers on communication and commitment, alongside a program of feeding a predetermined amount of a specific diet plus exercise and enrichment of the cat's life, offers a chance for a healthy result. PATIENT GROUP: It has been reported in some developed countries that as much as 40-50% of the feline population may be overweight or obese, with middle-aged cats, male cats, mixed-breed cats and neutered cats being at greatest risk. AUDIENCE: This review of what is currently known about the health risks, predisposing factors and treatment of excessive weight gain in cats is aimed at all veterinary health professionals. EVIDENCE BASE: The information reported in the review is drawn from the current scientific literature as well as from the clinical experience of the authors.  相似文献   
137.
Case history and presentationTwo non-human primates (Macaca fascicularis), weight 3.5 kg, enrolled in an experimental protocol received a 25 μg hour?1 transdermal fentanyl patch for postoperative analgesia. The following day both animals were clinically normal, but after a new induction of anaesthesia with ketamine, they developed severe and prolonged respiratory distress, profound coma and myosis.Management and follow-upAttempted reversal with naloxone was ineffective. After several hours of ventilation, both primates eventually died, 7 and 15 hours after ketamine injection, respectively. In both cases, the patch was discovered in the animal's cheek pouch. Subsequent fentanyl serum concentration measurements (8.29 and 14.80 μg L?1) confirmed fentanyl overdose.ConclusionsThis report of two fatal intoxications in non-human primates secondary to ingestion of a transdermal fentanyl patch demonstrates that this method of analgesia is inappropriate for non-human primates, because of their tendency to chew almost anything they can reach.  相似文献   
138.
In this study, cotton/nylon blended fabrics were treated with atmospheric air plasma at various times (30–60 s) and were subsequently printed with pastes containing carbon black nanoparticles. Properties of plasma treated fabrics such as visible-near infrared (Vis-NIR) reflectance, water contact angle, air permeability, and color fastness were measured. It was shown that increasing plasma treatment time decreases reflection level of treated fabrics in Vis-NIR region. Plasma treatment also enhanced the hydrophobicity of cotton/nylon fabrics observed by an increase in water contact angle. Plasma treated samples for 60 s demonstrated lower air permeability than those treated for 30 s. Furthermore, printed samples possessed acceptable levels of fastness against washing, light and crocking.  相似文献   
139.
Historically, the plains bison (Bison bison Linnaeus) was the most numerous and influential grazer on the Great Plains. Today 500 000 bison occupy North America among more than 100 000 000 cattle. In an attempt to restore their historical ecological role, bison are translocated onto landscapes previously manipulated for cattle use through water and fence development. We hypothesized that bison would use these landscapes similarly to cattle, thus maintaining homogenous grazing and reducing the restoration potential of bison at a landscape scale. We quantified differences between bison populations at different locations and spatial scales (American Prairie Reserve, Malta, Montana, USA, and Grasslands National Park, Val Marie, Saskatchewan, Canada, 2010–2011) and bison and cattle at similar locations and spatial scales using behavioral observations, movement analyses, and resource selection functions. Bison and cattle differed in all behaviors (grazing, standing, bedded, moving, other); however, landscape attributes resulted in behavior differences within species. Cattle spent a higher proportion of time grazing (45–49%) than bison (26–28%) and increased time at water. Bison moved at a 50–99% faster rate than cattle, and first passage time movement analyses identified selection of bison foraging patches (11 690 ha) larger than cattle foraging patches (48–615 ha). Similar to cattle, bison avoided most vegetation communities in relation to riparian communities and selected areas closer to water. Cattle selected for high plant biomass, whereas bison selected for intermediate plant biomass. This study has implications when bison and cattle are used to meet prairie restoration objectives. For bison, large landscapes that include variation in topography and vegetation communities are required. Furthermore, limiting manmade water sources may facilitate bison grazing patterns that more closely approximate historical bison use. For livestock, reduced movement and increased time spent grazing encourage grazing practices that increase heterogeneous grazing at a pasture scale.  相似文献   
140.
Rift Valley fever virus (Phlebovirus, Bunyaviridae) is an arbovirus causing intermittent epizootics and sporadic epidemics primarily in East Africa. Infection causes severe and often fatal illness in young sheep, goats and cattle. Domestic animals and humans can be contaminated by close contact with infectious tissues or through mosquito infectious bites. Rift Valley fever virus was historically restricted to sub-Saharan countries. The probability of Rift Valley fever emerging in virgin areas is likely to be increasing. Its geographical range has extended over the past years. As a recent example, autochthonous cases of Rift Valley fever were recorded in 2007–2008 in Mayotte in the Indian Ocean. It has been proposed that a single infected animal that enters a naive country is sufficient to initiate a major outbreak before Rift Valley fever virus would ever be detected. Unless vaccines are available and widely used to limit its expansion, Rift Valley fever will continue to be a critical issue for human and animal health in the region of the Indian Ocean.  相似文献   
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