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101.
To investigate the association between genital bacterial infection and urogenital carcinoma in California sea lions (Zalophus californianus), vaginal and preputial swabs for bacterial isolation were taken from 148 free-ranging and 51 stranded California sea lions including 16 animals with urogenital carcinoma. Cytological examination of vaginal or preputial smears showed a majority (65.5%, 57/87) of animals examined had mild or no inflammation. Aerobic bacteria were isolated from 116 (78.4%) wild sea lions and 100% of stranded animals. A total of 403 isolates were identified representing 51 unique bacterial species. The median number of isolates per animal increased with age in the wild group, but there was no difference in the number of isolates per animal between wild and stranded adults. The most common bacteria isolated from the wild sea lions were Psychrobacter phenylpyruvicus (39 isolates), non-hemolytic Streptococcus (35 isolates), Corynebacterium spp. (30 isolates), and Escherichia coli (20 isolates). More bacterial species were isolated from stranded animals than wild animals (33 versus 26) and there was significantly less growth of P. phenylpyruvicus, Corynebacterium spp., and Moraxella-like spp. in the stranded animals. Beta-hemolytic Streptococcus was the only bacterium significantly associated with urogenital carcinomas in California sea lions, but only in females.  相似文献   
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Abstract.— A 12-wk feeding trial was conducted in aquaria with juvenile (36.0 ± 1.2 g) largemouth bass Microptents salmoides to examine the effects of dietary supplementation of methionine, lysine, and long-chain polyunsaturated fatty acids (PUFA) on growth, feed conversion and body composition. Diets were formulated to increase dietary concentrations of methionine. lysine, and PUFAs to match levels found in whole body samples of largemouth bass. The control diet was formulated similar to diets previously tested for largemouth bass. Diets 2 and 3 were similar to the control diet hut were supplemented with 2% lysine and 1% methionine, respectively. Diet 4 was formulated to increase PUFAs, especially docosahexaenoic acid (DHA) (22:6n-3), by replacing menhaden fish oil with squid oil. Fish were fed all they would consume in 10 min, twice daily. At harvest, there were no statistically significant differences ( P > 0.05) in average individual weight or specific growth rate (SGR) among fish fed the four diets. The feed conversion ratio (FCR) of largemouth bass fed the diet supplemented with methionine (1.7) was significantly lower ( P ≤ 0.05) than fish fed the control diet (2.5). Fish fed the diet high in PUFA had significantly lower ( P ≤ 0.05) whole body lipid levels and significantly higher ( P ≤ 0.05) protein levels than fish fed the other three diets. These data indicate that the control diet in this study likely contained sufficient lysine, methionine and PUFA to meet the requirements of largemouth bass; however, additional methionine may improve feed conversion efficiency, and increased levels of PUFAs or other factors in squid oil may have a significant impact on body composition.  相似文献   
105.
The effects and interactions of added artificial substrate with different stocking densities of prawns were evaluated. Juvenile prawns (0.2 ± 0.1 g) were stocked into 12 0.04-ha ponds at 60,000ha and 120,000/ha with and without substrate. Added substrate consisted of horizontal plastic mesh and strips of oyster netting sutlicient to increase available surface area 80%. There were no statistically significant ( P > 0.05) interactions between stocking density and presence of added substrate, allowing these main effects to be compared separately. Increasing stocking density produced a significant increase ( P < 0.01) in total production but a significant decrease ( P < 0.01) in average prawn size and production ( P < 0.05) of market size prawns (>20 g, -27%; > 30 g, -56%). Added substrate also produced a significant increase ( P < 0.05) in total production (18%). However, average prawn size was not decreased and production of marketable shrimp was increased (>20 g, 25%; >30 g, 19%). Feed conversion ratios were significantly decreased (P < 0.01) by the presence of substrate. Increased stocking density significantly increased ( P < 0.05) the percentage of males which were small males (SM) and decreased ( P < 0.01) the percentage of orange claw males (OC), but had no impact ( P > 0.05) on numbers of reproductive (RF) and virgin (VF) female morphotypes. Increased stocking density also produced a significant decrease ( P < 0.05) in average size of OC, RF, and VF morphotypes while the addition of substrate had no statistically significant impact (P > 0.05) on the number or size of different morphotypes. The mathematical relationship between available surface area and average prawn size should be determined to produce recommended inclusion rates for added substrate based on desired levels of total production, stocking rates, and optimum market sizes.  相似文献   
106.
In contrast to the yellow color of pollen of European hazelnut (Corylus avellana L.) cultivars, an unusual cream color was observed in some seedlings from self-pollination of the Sicilian cultivar ‘Montebello.’ After elimination of accidental outcrosses, the segregation fit a 3 yellow: 1 cream ratio, indicating the possibility of simple genetic control. Two seedlings with cream-colored pollen were backcrossed to their parent ‘Montebello,’ and the progeny segregated 1 yellow: 1 cream for pollen color. When two seedlings with cream-colored pollen were crossed with each other, all of the resulting seedlings had cream-colored pollen. These segregation ratios indicate that pollen color in hazelnut is controlled by a single locus with yellow dominant to cream color. The symbol pc is proposed for this locus. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
107.
Shawn W. Laffan  Brian G. Lees 《Geoderma》2004,120(3-4):241-258
In this paper we assess the utility of mapping regolith properties as continuously varying fields using environmental correlation over large spatial areas. The assessment is based on a comparison of results from spatially global and local analysis methods.

The two methods used are a feed-forward, back propagation neural network, applied globally, and moving window regression, applied locally. These methods are applied to five regolith properties from a field site at Weipa, Queensland, Australia. The properties considered are the proportions of oxides of aluminum, iron, silica and titanium present in samples, as well as depth to the base of the bauxite layer. These are inferred using a set of surface measurable features, consisting of Landsat data, geomorphometric indices, and distances from streams and swamps.

The moving window regression results show a much stronger relationship than do those from the spatially global neural networks. The implication is that the scale of the analysis required for environmental correlation is of the order of hundreds of metres, and that spatially global analyses may incur an automatic reduction in accuracy by not modelling geographically local relationships. In this case, this effect is up to 45% error at a tolerance near half of a standard deviation.  相似文献   

108.
Bounty records from Montana (1902-1930) were used to better understand spatial and temporal response of wolves (Canis lupus) and cougars (Puma concolor) to an eradication program. Number of payments for wolves declined from a high of 4116 in 1903 to 0 by 1928. Numbers of cougar pelts fluctuated, but generally declined from 177 in 1908 to 2 in 1930. An inverse spatial relationship existed between density of payments for wolves and cougars. Payments for wolves were greatest in the Prairie ecoregion, while payments for cougars were greatest in the Montane. The ratio of pup to adult wolves also was greatest in the Prairie ecoregion and least in the montane. If distribution and frequency of bounty payments were a reflection of the distribution and abundance of wolves, populations were highest and most productive in areas where they currently do not occur.  相似文献   
109.
BACKGROUND: In sub-Saharan Africa, underweight and micronutrient deficiencies account for an estimated 25% of the burden of disease. As the coverage of national health systems expands, increased opportunities exist to address the needs of children and women, the most vulnerable to these deficiencies, through high-quality nutrition services. OBJECTIVES: To assess health providers' knowledge and practice with regard to essential nutrition services for women and children in Burkina Faso, Mozambique and Niger, in order to assist the development of a standard guide and tools to assess and monitor the quality of the nutrition services delivered through national health systems. FINDINGS: The three surveys reveal the extent of missed opportunities to deliver nutrition services during routine prenatal, postnatal and child-care consultations for the prevention and treatment of highly prevalent nutritional deficiencies. CONCLUSION: A commitment to improving the quality of facility-based nutrition services is necessary to impact on the health outcomes of women and children 'covered' by national health systems. Rigorous assessment and monitoring of the quality of nutrition services should inform health programme and policy development. Building on the lessons learned in these three assessments, Helen Keller International has developed a standard Guide and Tools to assess the quality of the nutrition services delivered through national health systems. These tools can be adapted to assess ongoing nutrition services in health facilities, provide a framework for nutrition programming, inform the development of pre-service as well as in-service nutrition training curricula for providers, and evaluate the impact of nutrition training on providers' practices.  相似文献   
110.
The US Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository in Corvallis, Oregon, preserves more than 800 accessions of hazelnut (Corylus), including C. avellana cultivars and representatives of 10 other recognized shrub and tree species. Characterization and study of genetic diversity in this collection require cross-transferable markers, such as trinucleotide microsatellite or simple sequence repeat (SSR) markers and universal chloroplast SSR markers. We developed new SSR markers and evaluated 114 Corylus accessions representing 11 species and 44 interspecific hybrids. Eight of 23 SSRs generated easy-to-score alleles in all species and seven were highly polymorphic. For those seven, the average heterozygosity was moderate at 0.49, and mean allele number, genetic diversity and polymorphism information index were high at 11.71, 0.79 and 0.76, respectively. The three most polymorphic SSRs were CaC-C008, CaC-C040 and CaC-C118. Neighbor-joining (NJ) clustering and structure analysis agreed with classical taxonomic analysis and supported inclusion of C. maxima within the large polymorphic species, C. avellana. Analysis also indicated that C. californica is a distinct species rather than a botanical variety of C. cornuta. Six universal cpSSRs were polymorphic in Corylus and generated 21 distinct chlorotypes with an average of 3 alleles per locus. Diversity at these cpSSRs was high and ranged from 0.33 to 0.64, with an average of 0.54. Incongruence in NJ topologies between the nuclear and chloroplast markers could be attributed to chloroplast capture related to hybridization during the ancestral diversification of the genus, or to homoplasy. The phylogeographical relationships among the 21 chlorotypes in the 11 Corylus species support Asia as a refugium where several hazelnut lineages survived during glaciation and from which they continued to evolve after dispersal from Asia through the Mediterranean to Europe, and across the Atlantic and/or the Bering land bridge to North America.  相似文献   
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