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61.
The surface evenness and texture are closely related with the irregularity of yarn thickness. Besides, yarn thickness variation has an important role to influence the yarn performance and the textile process efficiency. Thus, the information not only on the yarn thickness, but also on the short- term irregular characteristics that have not been known before is required for enhancing the qualities of textile products. This paper reports the results of a study about the yarn thickness and its variation for various types of yarn on the basis of a new measurement system applying a laser slit beam as a light source. The new method delivers effective information on the irregularity. The analysis of the measured signal confirms that the visual shade created by the yarn doubling and twisting can be measured and the yarn thickness characteristics can be represented by correlograms. Depending on yarn types, correlograms have different shapes and can be approximated to an exponentially decaying function with or without fluctuating magnitude. In addition, the effective information on the yarn irregularity can be influenced by the sampling length interval of the measuring device used for tests.  相似文献   
62.
We induced percutaneous spinal cord injuries (SCI) using a balloon catheter in 45 rats and transplanted human umbilical cord blood derived mesenchymal stem cells (hUCB-MSCs) at the injury site. Locomotor function was significantly improved in hUCB-MSCs transplanted groups. Quantitative ELISA of extract from entire injured spinal cord showed increased expression of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) and neurotrophin-3 (NT-3). Our results show that treatment of SCI with hUCB-MSCs can improve locomotor functions, and suggest that increased levels of BDNF, NGF and NT-3 in the injured spinal cord were the main therapeutic effect.  相似文献   
63.
Growth differentiation factor 11 (GDF11) regulates cell growth and differentiation in both embryonic and adult tissues. Circulating GDF11 levels have recently been reported to be significantly lower in aging mice and restoration of GDF11 reversed age-related cardiac hypertrophy in old mice. Here, we evaluated the potential of serum levels of GDF11 as a circulating biomarker in dogs at different stages of heart failure, due to chronic mitral valve insufficiency (CMVI). We found no significant differences in serum GDF11 levels between dogs at different stages of CMVI-associated heart failure. Furthermore, the circulating levels of GDF11 did not correlate with age, body weight, echocardiographic variables, and the severity of CMVI-induced heart failure in dogs.  相似文献   
64.
Laboratory studies on the formation of bound residues and on the degradation of the triazole fungicide propiconazole were conducted in two different soils. Soils treated with 14C-propiconazole were incubated at 22 degrees C and extracted exhaustively with a solvent at each sampling date until no further propiconazole was extracted. The solvent-extractable residues were used to measure propiconazole remaining in the soil, and the extracted soils were used to investigate bound residues of propiconazole. Mineralization of propiconazole was investigated by measuring [14C]carbon dioxide evolved from the soil samples. Formation of bound residues of propiconazole was higher in silty clay loam soil than in sandy loam soil, giving approximately 38 and 23% of the applied 14C, respectively. In contrast, the rates of degradation and mineralization of propiconazole were lower in silty clay loam soil than in sandy loam soil. Decreased extractability of the 14C residues with incubation time was observed with increased formation of bound residues. When the propiconazole remaining in the solvent-extractable residues was quantitatively measured by high-pressure liquid chromatographic analysis, the half-life value in sandy loam soil was about 315 days, while the half-life in silty clay loam soil exceeded the duration of the 1 year experimental period. Increased formation of bound residues was observed as propiconazole degraded with incubation time, suggesting that degradation products are involved in the formation of bound residues. Our study suggests that the formation of bound residues of propiconazole contributes to the persistence of this fungicide in soil.  相似文献   
65.
A total of 10 species of psyllids from 8 different countries were intercepted by plant health inspectors in South Korea on consignments of fresh cut flowers (and branches for use in flower arrangements) at the ports of entry in South Korea from 2014 to 2018. Of the 10 species that were intercepted, some species are potential pests that could enter and establish in Korea through the import of these flowers and branches. Current information on intercepted psyllids is required to alert plant health inspectors to look carefully at cut flowers to prevent the introduction of non-indigenous species.  相似文献   
66.
Doubled haploid wheat lines developed from a cross between a hard white winter wheat variety of normal starch endosperm and a waxy wheat variety were used to determine the effects of allelic variation in Wx‐1, Glu‐D1, Glu‐B3, and Pinb‐D1 loci on physiochemical properties of flour, noodle dough properties, and textural quality of cooked noodles. Milling yield, damaged starch content, protein content, and SDS sedimentation volume of flour were influenced the most by allelic composition of Pinb‐D1 loci, less by Wx‐1 loci, and least by Glu‐B3. Wheat lines carrying Pinb‐D1b or Glu‐B3h alleles exhibited higher milling yield and damaged starch content of flour than those with Pinb‐D1a and Glu‐B3d alleles. Wheat lines carrying the Pinb‐D1b allele were higher in protein content and SDS sedimentation volume than those carrying Pinb‐D1a. Mixograph water absorption was largely influenced by allelic composition of Wx‐1 loci, whereas mixograph mixing time and mixing tolerance were predominantly determined by allelic composition of Glu‐D1 loci. Amylose content and pasting properties of starch were mainly determined by allelic composition of Wx‐1 loci with little influence by allelic compositions of Glu‐D1, Glu‐B3, and Pinb‐D1 loci. Allelic composition of Wx‐1 loci contributed 53.4% of the variation in optimum water absorption of noodle dough and 26.7% of the variation in thickness of the noodle dough sheet. The variation of 7.8% in optimum water absorption of noodle dough was contributed by the allelic composition of Pinb‐D1 loci. Allelic composition of Wx‐1 loci was responsible for 73.2, 74.4, and 59.6% in the variation of hardness, springiness, and cohesiveness of cooked noodles, respectively. Cohesiveness of cooked noodles was also influenced by the allelic compositions of Glu‐B3 and Pinb‐D1 loci to a smaller extent.  相似文献   
67.
Cochliobolus miyabeanus forms a specialized infection structure, an appressorium, to infect rice. Contacting a hard surface induces appressorium formation in C. miyabeanus, while the hydrophobicity of the substratum does not affect this morphogenic infection event. To determine whether the calcium/calmodulin-dependent signaling system is involved in prepenetration morphogenesis in C. miyabeanus, the effects of a calcium chelator (ethylene glycol tetraacetic acid; EGTA), phospholipase C inhibitor (neomycin), intracellular calcium channel blocker (TMB-8), calmodulin antagonists (chlorpromazine, phenoxybenzamine, and W-7), and calcineurin inhibitor (cyclosporin A) on morphogenesis and infection were examined. Addition of Ca2+ and the calcium ionophore A23187 did not affect conidial germination, while the number of appressoria decreased with higher concentrations. EGTA inhibited conidial germination and appressorium formation. The calcium channel blocker did not affect appressorium formation at any concentration; however, calmodulin antagonists and the calcineurin inhibitor specifically reduced appressorium formation at the micromolar level. One of the calmodulin antagonists, W-7, also inhibited accumulation of mRNA of the calmodulin gene within germinating conidia and/or appressorium-forming germ tubes. Thus, biochemical processes controlled by the calcium/calmodulin signaling system seem to be involved in the induction of prepenetration morphogenesis on rice.  相似文献   
68.
ABSTRACT To investigate host specialization in Macrophomina phaseolina, the fungus was isolated from soybean, corn, sorghum, and cotton root tissue and soil from fields cropped continuously to these species for 15 years in St. Joseph, LA. Chlorate phenotype of each isolate was determined after growing on a minimal medium containing 120 mM potassium chlorate. Consistent differences in chlorate sensitivity were detected among isolates from different hosts and from soil versus root. To further explore genetic differentiation among fungal isolates from each host, these isolates were examined by restriction fragment length polymorphism and random amplified polymorphic DNA (RAPD) analysis. No variations were observed among isolates in restriction patterns of DNA fragments amplified by polymerase chain reaction covering the internal transcribed spacer region, 5.8S rRNA and part of 25S rRNA, suggesting that M. phaseolina constitutes a single species. Ten random primers were used to amplify the total DNA of 45 isolates, and banding patterns resulting from RAPD analysis were compared with the neighbor-joining method. Isolates from a given host were genetically similar to each other but distinctly different from those from other hosts. Chlorate-sensitive isolates were distinct from chlorate-resistant isolates within a given host. In greenhouse tests, soybean, sorghum, corn, and cotton were grown separately in soil infested with individual isolates of M. phaseolina that were chosen based on their host of origin and chlorate phenotype. Root colonization and plant weight were measured after harvesting. More colonization of corn roots occurred when corn was grown in soil containing corn isolates compared with isolates from other hosts. However, there was no host specialization in isolates from soybean, sorghum, or cotton. More root colonization in soybean occurred with chlorate-sensitive than with chlorate-resistant isolates.  相似文献   
69.
Active compounds with antidiabetic potential were isolated from silk peptide E5K6 by consecutive ultrafiltration and gel filtration using Biogel P-2 and RS-HPLC using a YMC-Pack Pro C18 column. The highest α-glucosidase inhibitory activity of silk peptide E5K6 resulted from fractions with MW <1 kDa. The activities of gel-filtered fractions from silk peptide E5K6 of <1 kDa were assayed in vitro, demonstrating that the fourth peak (F4) had the highest α-glucosidase inhibitory activity (IC(50) = 37.1 mg/mL). F4 of silk peptide E5K6 was separated by HPLC into two peaks. Moreover, the purified compounds were identified as Gly-Glu-Tyr (GEY, MW = 367 Da) and Gly-Tyr-Gly (GYG, MW = 295 Da) according to amino acid sequences, and their α-glucosidase inhibitory activities (IC(50)) were 2.7 and 1.5 mg/mL, respectively.  相似文献   
70.
BackgroundSince 2003, the H5 highly pathogenic avian influenza (HPAI) subtype has caused massive economic losses in the poultry industry in South Korea. The role of inland water bodies in avian influenza (AI) outbreaks has not been investigated. Identifying water bodies that facilitate risk pathways leading to the incursion of the HPAI virus (HPAIV) into poultry farms is essential for implementing specific precautionary measures to prevent viral transmission.ObjectivesThis matched case-control study (1:4) examined whether inland waters were associated with a higher risk of AI outbreaks in the neighboring poultry farms.MethodsRivers, irrigation canals, lakes, and ponds were considered inland water bodies. The cases and controls were chosen based on the matching criteria. The nearest possible farms located within a radius of 3 km of the case farms were chosen as the control farms. The poultry farms were selected randomly, and two HPAI epidemics (H5N8 [2014–2016] and H5N6 [2016–2017]) were studied. Conditional logistic regression analysis was applied.ResultsStatistical analysis revealed that inland waters near poultry farms were significant risk factors for AI outbreaks. The study speculated that freely wandering wild waterfowl and small animals contaminate areas surrounding poultry farms.ConclusionsPet birds and animals raised alongside poultry birds on farm premises may wander easily to nearby waters, potentially increasing the risk of AI infection in poultry farms. Mechanical transmission of the AI virus occurs when poultry farm workers or visitors come into contact with infected water bodies or their surroundings. To prevent AI outbreaks in the future, poultry farms should adopt strict precautions to avoid contact with nearby water bodies and their surroundings.  相似文献   
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