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991.
ABSTRACT

Breed assignment was performed for pigs putatively belonging to Pied Danish Pigs, an endangered Danish conservation breed. DNA array data were available for the candidates who had insufficient pedigree information. So were data for a reference population of animals from Danish conservation breeds as well as data from a range of Northern European pig breeds, and wild boar. Breed proportions were estimated using the program ADMIXTURE. Half the candidates were found to have at least 95% of their ancestry from Pied Danish Pigs. Several candidates showed varying degrees of admixture with other breeds, most notably Gloucester Old Spot. The same was observed for several of the Pied Danish Pig reference animals. The analyzes identified suitable breeding candidates and prevented unwanted recent admixture from spreading in the breeding population.  相似文献   
992.
993.
Rangelands and savannas occupy 70% of the Australian continent and are mainly used for commercial grazing of sheep and cattle. In the center and north, where there are extensive areas of indigenous land ownership and pastoral production is less intensive, savanna burning is frequent. Greenhouse gas emissions from rangelands have been overwhelmingly from land clearing and methane production by livestock. Reductions in the rate of land clearing have substantially reduced Australia’s greenhouse gas emissions, but these have been controversial with the reduced potential pasture production being of concern to many land managers. Reductions in direct livestock emissions are possible through manipulation of the genetics, rumen flora, or diet of animals. However, the greatest potential benefit is a whole-property approach with improved animal husbandry and attention to other aspects of property management such as fossil fuel consumption. Focus on emissions per unit of land area is likely to have other ecological benefits for land condition and to capture the effects of changes in carbon stocks in vegetation and soils. In much of northern and central Australia, changes in settlement patterns have led to more frequent and intense fires than under indigenous management regimes before European settlement. The implementation of more benign regimes of savanna burning has great potential benefit for greenhouse abatement, biodiversity, and livelihoods of indigenous people in remote settlements.  相似文献   
994.
The study aimed to address the optimal plant population density in maize that maximizes phenotypic expression and differentiation, and lessens environmental effects on genotypic expression in terms of the response to selection. A set of seven short-season hybrids (Rom set) was tested under rainfed conditions (2006, 2007) in Romania, and a set of seven long-season hybrids (Gr set) was tested with irrigation (2007) in Greece. Experimentation was conducted under ultra-low (ULD), low (LD), middle (MD), and high (HD) densities (0.74, 2.51, 4.20, 8.40 plants/m2 for the Rom set, and 0.74, 3.13, 6.25, 8.33 plants/m2 for the Gr set). Phenotypic expression and differentiation for grain yield were highest at the ULD. Coefficient of variation (CV) for grain yield, ear length and kernel row number decreased as density decreased. Environmental conditions and hybrid plant-yield potential (i.e., maximum yield per plant) were crucial for the optimal density that achieved the lowest environmental variance. For the Rom set the lowest CV for grain yield was obtained at the LD in the unfavourable season and at the ULD in the favourable season. The less acquired variance was achieved at the ULD for the highest yielding hybrids and at the LD for the lowest yielding hybrids, revealing a negative association between plant-yield potential and optimal density. Concluding, a density proximal to the ULD approximates absence of competition in maize, and optimizes three determinant parameters for successful selection: selection intensity, heritability and phenotypic differentiation.  相似文献   
995.
通过对石河子市近一年的降水pH值的分析,提出了大气降水酸碱度本底值的概念。并认为实际所测降水的pH值是在该本底值的基础上,由人类活动而排放NOx、SOx、粉尘等污染物质对其施以影响而形成的综合指标。季节性变化明显。总体上,石河子地区夏季降水pH较大,偏向于弱碱性;冬季降水pH值较小,偏向于弱酸性,春、秋两季次之。  相似文献   
996.
A central tenant of ecohydrology in drylands is that runoff redistribution from bare to vegetated patches concentrates the key limiting resource of water, which can then enhance vegetation growth and biomass. Conversely, a reduction in vegetation patches, particularly those associated with herbaceous plants, can lead to a threshold-like response in which bare patches become highly interconnected, triggering a large increase in hillslope runoff and associated erosion. However, generally lacking is an assessment of how maximization of run-on to herbaceous patches relates to minimization of hillslope-scale runoff. To illustrate how runoff redistribution potentially changes in response to conversion of herbaceous patches to bare ones, we used a spatially distributed model, SPLASH (Simulator for Processes at the Landscape Surface–Subsurface Hydrology), with an example of a semiarid piñon–juniper woodland hillslope with seven combinations of bare and herbaceous patch cover, culminating in complete loss of herbaceous patches, for a 1-yr design storm. As expected, the amount of hillslope runoff increased curvilinearly with reductions in herbaceous cover as runoff per cell increased from bare patches and run-on per cell increased for herbaceous patches. Notably, the total amount of run-on to all herbaceous patches was greatest when the amount of bare cover was intermediate, highlighting a trade-off between the source area for generating runoff and the sink area for capturing run-on. The specific nature of patch–hillslope runoff redistribution responses certainly depends on several site-specific conditions, but the general nature of the response exhibited in our example simulation may be indicative of a general type of response applicable to many rangelands. We suggest that a more robust suite of such relationships could be valuable for managing rangelands by enabling explicit accounting for optimality and trade-offs in biomass per herbaceous patch, total herbaceous cover, and prevention of hillslope-scale connectivity of bare patches that triggers a large increase in runoff and associated erosion.  相似文献   
997.
The International Federation of Societies of Toxicologic Pathologists (IFSTP) proposes a common global framework for training future toxicologic pathologists who will support regulatory-type nonclinical toxicology studies. Trainees optimally should undertake a scientific curriculum of at least 5 years at an accredited institution leading to a clinical degree (veterinary medicine or medicine). Trainees should then obtain 4 or more years of intensive pathology practice during a residency and/or on-the-job "apprenticeship," at least 2 years of which must be focused on regulatory-type toxicologic pathology topics. Possession of a recognized pathology qualification (i.e., certification) is highly recommended. A non-clinical pathway (e.g., a graduate degree in medical biology or pathology) may be possible if medically trained pathologists are scarce, but this option is not optimal. Regular, lifelong continuing education (peer review of nonclinical studies, professional meetings, reading, short courses) will be necessary to maintain and enhance one's understanding of current toxicologic pathology knowledge, skills, and tools. This framework should provide a rigorous yet flexible way to reliably train future toxicologic pathologists to generate, interpret, integrate, and communicate data in regulatory-type, nonclinical toxicology studies.  相似文献   
998.
Cells from some tumors use an altered metabolic pattern compared with that of normal differentiated adult cells in the body. Tumor cells take up much more glucose and mainly process it through aerobic glycolysis, producing large quantities of secreted lactate with a lower use of oxidative phosphorylation that would generate more adenosine triphosphate (ATP), water, and carbon dioxide. This is the Warburg effect, which provides substrates for cell growth and division and free energy (ATP) from enhanced glucose use. This metabolic switch places the emphasis on producing intermediates for cell growth and division, and it is regulated by both oncogenes and tumor suppressor genes in a number of key cancer-producing pathways. Blocking these metabolic pathways or restoring these altered pathways could lead to a new approach in cancer treatments.  相似文献   
999.

Background

Anaplasmosis is a vectorborne disease caused by the gram-negative bacterium Anaplasma phagocytophilum. This species displays positive tropism to granulocytes and can cause illness in several mammalian species, including cats, dogs, and humans. It is considered as an emerging disease in Europe. The clinical signs are nonspecific and include fever, lethargy, and inappetence. The most typical hematologic abnormality is thrombocytopenia. A tentative diagnosis can be made by detecting intracytoplasmic morulae inside neutrophils. The diagnosis is confirmed by PCR and serology in paired serum samples. A sample for PCR analysis should be taken before treatment. Anaplasmosis is treated with doxycycline.

Case presentation

A feline case of anaplasmosis is presented. The history, clinical presentation, diagnostics, treatment, and follow-up are discussed.

Conclusions

This case indicates that Anaplasma phagocytophilum infects cats in Finland. To provide accurate treatment, anaplasmosis should be listed as a differential diagnosis in cats suffering from acute febrile illness with previous tick exposure.  相似文献   
1000.
The prevalence of influenza A virus infection, and the distribution of different subtypes of the virus, were studied in 1529 ducks and 1213 gulls shot during ordinary hunting from August to December in two consecutive years, 2006 and 2007, in Norway. The study was based on molecular screening of cloacal and tracheal swabs, using a pan-influenza A RT-PCR. Samples found to be positive for influenza A virus were screened for the H5 subtype, using a H5 specific RT-PCR, and, if negative, further subtyped by a RT-PCR for the 3''-part of the hemagglutinin (HA) gene, encompassing almost the entire HA2, and the full-length of the neuraminidase (NA) gene, followed by sequencing and characterization. The highest prevalence (12.8%) of infection was found in dabbling ducks (Eurasian Wigeon, Common Teal and Mallard). Diving ducks (Common Goldeneye, Common Merganser, Red-breasted Merganser, Common Scoter, Common Eider and Tufted Duck) showed a lower prevalence (4.1%). In gulls (Common Gull, Herring Gull, Black-headed Gull, Lesser Black-headed Gull, Great Black-backed Gull and Kittiwake) the prevalence of influenza A virus was 6.1%. The infection prevalence peaked during October for ducks, and October/November for gulls. From the 16 hemagglutinin subtypes known to infect wild birds, 13 were detected in this study. Low pathogenic H5 was found in 17 dabbling ducks and one gull.  相似文献   
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