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91.
Japanese encephalitis virus (JEV) causes a mosquito-borne viral zoonosis that is becoming increasingly important to public health in east and south Asia. Although JEV is primarily associated with reproductive failure in swine, JEV infection can cause fever and headache in humans and is associated with aseptic meningitis and encephalitis. The exact mode of transmission, including host range and possible source of viral amplification within livestock, is still not completely clear. This study consisted of a serological survey of JEV infection in goats. A total of 804 goat serum samples were collected from 144 farms in Korea between May 2005 and May 2006. The incidence of positive cases was 12.1% (97 out of 804 goats). The seroprevalence of JEV infection in the 144 farms screened was 31.3% (45/144), indicating that JEV infection is frequent in goat farms in Korea. In addition, three districts of Korea (mainly in the southern region) had a higher seroprevalence of JEV compared to other areas. The results suggest that goats could be monitored epidemiologically as a sentinel animal for JEV transmission in Korea.  相似文献   
92.
We constructed sugi site index models using digital-terrain-analysis-based environmental factors for Miyazaki Prefecture. We selected 18 sugi plantation stands which were pure, undisturbed, and over 40 years old, planted with the same sugi-cutting cultivar, and managed by normal forest operations. The dominant tree in each stand was felled for stem analysis. Site index, defined here as dominant tree height at 40 years old, was estimated by stem analysis for each stand. Five types of DEMs were used: 100- and 50-m resolution derived from DEMs published by the Geographical Survey Institute, and 50-, 25-, and 12.5-m resolution derived from digital contour map manually generated from a 1:25,000 topographic map. A total of 14 indices categorized into solar radiation index, wetness index, and topographic exposure index were used to model the site index by multiple linear regression analysis. Through model selection procedures, the best-fitted site index models were selected for each type of DEM. The most precise model was that of the 12.5-m-resolution DEM (R 2 = 0.692), following the model of the published 50-m-resolution DEM (R 2 = 0.665). Site productivity of sugi was severely limited by direct solar radiation. Soil wetness also affected sugi site productivity; however, it can only be represented using a high-resolution DEM derived from fine-scale data. Our results suggest that the 50-m-resolution DEM published by the Geographical Survey Institute can be used for site index modeling.  相似文献   
93.
Composite biological and synthetic grafts with progenitor cells offer an alternative approach to auto- or allografts for fracture repair. This study was conducted to evaluate osteogenesis of autologous serum-derived albumin (ASA) scaffolds seeded with canine adipose tissue-derived mesenchymal stem cells (Ad-MSCs) in a canine segmental bone defect model. ASA scaffold was prepared with canine serum using cross-linking and freeze-drying procedures. Beta-tricalcium phosphate (β-TCP) was mixed at the cross-linking stage. Ad-MSCs were seeded into the scaffold and incubated for one day before implantation. After 16 weeks, the grafts were harvested for histological analysis. The dogs were divided into five groups: control, ASA scaffolds with and without Ad-MSCs, and ASA scaffolds including β-TCP with and without Ad-MSCs. ASA scaffolds with Ad-MSCs had a significantly larger area of increased opacity at the proximal and distal host cortex-implant interfaces in radiographs 16 weeks after implantation compared to the groups with β-TCP (p < 0.05). Histomorphometric analysis showed that ASA scaffolds with Ad-MSCs had significantly greater new bone formation than other groups (p < 0.05). These results suggest that Ad-MSCs seeded into ASA scaffolds enhanced osteogenesis in the bone defect model, but that β-TCP in the ASA scaffold might prevent penetration of the cells required for bone healing.  相似文献   
94.
The genome sequencing of all major food and bioenergy crops is of critical importance in the race to improve crop production to meet the future food and energy security needs of the world. Next generation sequencing technologies have brought about great improvements in sequencing throughput and cost, but do not yet allow for de novo sequencing of large repetitive genomes as found in most crop plants. We present a strategy that combines cutting edge next generation sequencing with “old school” genomics resources and allows rapid cost-effective sequencing of plant genomes.  相似文献   
95.
Genomewide association study (GWAS), which queries the association between loci and a particular trait by examining single nucleotide polymorphisms (SNPs) of the entire genome, is used in many fields of study. The development of next‐generation sequencing techniques has facilitated GWASs by decreasing the sequencing costs and time. In particular, genotyping by sequencing (GBS) is useful for sequencing many samples simultaneously and at a moderate price. Herein, we describe a potential GWAS using GBS, focused on the apple germplasm, with the goal of developing an effective apple breeding strategy through the identification of useful markers. From 308 Korean apple germplasm, SNPs were selected after GBS, and major traits were investigated. Proprietary individuals were confirmed and grouped by association through genetic diversity and population structure analyses of the selected SNPs. Genes highly associated with the target traits were identified, respectively. As the first GWAS report on the apple germplasm, these results will be useful as base data for GWASs on other apple populations and traits.  相似文献   
96.
The Tonle Sap River and Lake (TSRL) is South‐East Asia's largest tropical flood pulse with a flow‐reversal system that supports one of the world's largest freshwater fisheries. However, among the world's tropical floodplains, the resources of the TSRL have received little ecological research. Here, we described the spatiotemporal TSRL fish diversity and community variation using daily records from 2012 to 2015 on fish abundance from six sites covering the TSRL system. We found that high fish diversity occurred in sites located in the middle of Tonle Sap Lake, and the lowest diversity was observed in the southern section. The spatial abundance distribution patterns displayed a river–lake gradient, with three fish assemblages that were clustered based on their composition similarities and were characterised by 96 indicator species. In the southern section, fish assemblages were characterised by longitudinal migratory fishes; in contrast, in the middle system, fish assemblages were represented by species with combined ecological attributes (i.e. longitudinal and lateral migratory species and floodplain residents). Towards the northern section, fish assemblages were composed of lateral migratory and floodplain resident species. Species richness and abundance peaked at approximately 2–2.5 and 4 months, respectively, after the peak flow in early October, during which Tonle Sap River resumes its normal flow direction (outflow). This suggests that seasonal flood pulses (i.e. rising and falling water levels) play a pivotal role in structuring spatiotemporal variation in the TSRL fish assemblages. Our study has implications for fisheries monitoring and conservation initiatives.  相似文献   
97.
Twenty 70-year-old longleaf pine trees from a spacing, thinning, and pruning study were harvested, from which samples were analyzed for gross calorific value (GCV). A strong correlation was found between GCV and extractive contents for the unextracted wood samples. Although lignin content should impact GCV, no correlation was found between the variation in GCV with lignin content for the extractive-free wood samples. Mid-IR spectroscopy coupled with multivariate analysis provided strong correlations between the mid-IR-predicted and calorimetry-determined values for the unextracted wood samples. Plotting the regression coefficients for GCV and extractive contents showed that the same mid-IR bands were responsible for the strength of these models. Spectral differences were observed between the different extract samples, and relative peak intensities appeared to be dependent upon the extractive contents from the wood samples. Thus, models were also built based on the corresponding wood extractive contents using the actual extracts. These provided good correlations, suggesting a proportional change in extractive compositions coinciding with the total amount of extractives present in the unextracted wood samples.  相似文献   
98.
Elevated rates of methicillin‐resistant Staphylococcus aureus (MRSA) carriage have been reported in veterinary personnel, suggesting an occupational colonization risk. Hong Kong veterinary personnel (n = 150) were sampled for coagulase‐positive staphylococci (CPS) nasal colonization. Risk factors for colonization were assessed by questionnaire. Isolates were identified and antibiotic susceptibility determined. All CPS isolates were investigated for mecA carriage, SCCmec type and PVL genes. Two subjects were colonized with methicillin‐resistant CPS: one with MRSA (spa type t002 (CC5), SCCmec type II) and one with methicillin‐resistant Staphylococcus pseudintermedius (MRSP) (MLST type ST71, SCCmec type II‐III). MLST type ST71 S. pseudintermedius strain is the predominant MRSP clone circulating in dogs in Europe and in Hong Kong. The low MR‐CPS colonization rate may be associated with low levels of large animal exposure or low rates of MRSA colonization of companion animals in Hong Kong. Colonization with non‐aureus CPS, which may cause human infection, must also be considered in veterinary personnel.  相似文献   
99.
Intrinsic nonuniformity in the polycrystalline-silicon backplane transistors of active matrix organic light-emitting diode displays severely limits display size. Organic semiconductors might provide an alternative, but their mobility remains too low to be useful in the conventional thin-film transistor design. Here we demonstrate an organic channel light-emitting transistor operating at low voltage, with low power dissipation, and high aperture ratio, in the three primary colors. The high level of performance is enabled by a single-wall carbon nanotube network source electrode that permits integration of the drive transistor and the light emitter into an efficient single stacked device. The performance demonstrated is comparable to that of polycrystalline-silicon backplane transistor-driven display pixels.  相似文献   
100.
The application of a degassing system to mercerization process was investigated. It was found that the physical properties of cotton fabrics mercerized in the degassed NaOH solution were superior to those mercerized in NaOH solution. The degree of penetration of the degassed water was examined by measuring wicking height. The wicking height in the degassed water without the wetting agent is higher than that of the saturated water with 0.1 % of wetting agent.  相似文献   
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