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661.
Jeffery W. Bentley Jorge Andrade-Piedra Paul Demo Beloved Dzomeku Kim Jacobsen Enoch Kikulwe 《Journal of Crop Improvement》2018,32(5):599-621
Vegetatively propagated crop (VPC) seed tends to remain true to varietal type but is bulky, often carries disease, and is slow to produce. So VPC seed needs to be handled differently than that of other crops, e.g., it tends to be sourced locally, often must be fresh, and it is less often sold on the market. Hence, a framework was adapted to describe and support interventions in such seed systems. The framework was used with 13 case studies to understand VPC seed systems for roots, tubers, and bananas, including differing roles and sometimes conflicting goals of stakeholders, and to identify potential coordination breakdowns when actors fail to develop a shared understanding and vision. In this article, we review those case studies. The framework is a critical tool to (a) document VPC seed systems and build evidence; (b) diagnose and treat coordination breakdown and (c) guide decision-makers and donors on the design of more sustainable seed system interventions for VPCs. The framework can be used to analyze past interventions and will be useful for planning future VPC seed programs. 相似文献
662.
This study develops a method to evaluate the contact coolness of fabric using the infrared thermal image of a small test specimen. By using infrared thermal images of 7 types of fabrics developed as cool fabric, the average temperature difference on the surface of the human palm and a heating plate, with and without fabric was measured and this was used for the scale of the ability of the fabric to cool by touch. By comparing the average temperature differences with the Qmax of a fabric, absorption coolness, subjective contact coolness, and correlations were investigated. More heat is transmitted via fabric when the Qmax value is higher and average temperature difference of thermogram image is smaller, which means the coolness perceived by the skin becomes stronger. Fabric with a small average temperature difference in infrared thermal imaging had a high Qmax value and it was evaluated as having strong coolness in subjective evaluation too. However, it was found that there was no relationship between average temperature differences and absorption coolness. Therefore, it can be concluded that the evaluation of fabrics’ coolness using infrared thermal image is useful when evaluating contact coolness at the point of physical contact. In addition, by comparing the methods using the palm and heating plate, the method using the palm showed higher correlation with Qmax (-.828, p<0.05). Therefore, we confirmed that evaluating the coolness of small test specimens using an infrared thermal camera and the palm is effective. 相似文献
663.
This study examined the effects of the total porosity, pore size, and cover factor on the moisture and thermal permeability of woven fabrics made from DTY (draw textured yarns) and ATY (air jet textured yarns) composite yarns with hollow PET (polyethylene terephthalate) yarns. The wicking of the hollow composite yarn fabrics was found to be superior to that of the high twisted yarn fabrics, which may be due to the high porosity in the hollow composites yarns, but this was not related to the cover factor. The drying characteristics of the hollow composite yarn fabric with high porosity were inferior compared to the high twisted yarn fabrics due to the large amounts of liquid water in the large pores, which resulted in a longer drying time of the fabric. The thermal conductivity of the hollow composite yarn fabrics decreased with increasing measured pore diameter due to the bulky yarn structure. The effects of the hollowness of the yarn on the thermal conductivity were more dominant than those of the yarn structural parameters. The air permeability increased with increasing measured pore diameter but the effects of the cover factor on the air permeability were not observed in the hollow composite yarn fabrics. The effects of porosity on the moisture and thermal permeability of the woven fabrics made from the hollow composite filaments were found to be critical, i.e., wicking and air permeability increase with increasing porosity. In addition, the drying rate increased with increasing porosity and the thermal conductivity decreased with increasing pore diameter, but were independent of the cover factor. 相似文献
664.
To develop reusable incontinence products, blend nonwovens of hollow viscose rayon (HVR) and super absorbent fibers (SAFs) were prepared using a needle-punching process and their liquid handling properties, such as the fluid absorption capacity, fluid retention capacity, fluid absorption under load, moisture evaporation rate, and repeated water absorption were investigated. As the SAF content in the HVR/SAF blend nonwovens was increased, the fluid absorption capacity, fluid retention capacity, and fluid absorption under load increased, whereas the moisture evaporation rate decreased. SAF had a more significant effect on fluid retention than fluid absorption. In the case of HVR/SAF(8/2) and HVR/SAF(7/3), more than 100 % of the fluid absorption capacity was retained even after 5 cycles of repeated water absorption tests. Overall, the HVR/SAF blend nonwovens are good candidates for reusable incontinence products. 相似文献
665.
This study is to evaluate the future potential climate impact on snow hydrology using SLURP model for a 6661.0 km2 mountainous watershed of South Korea. For the model test, the NOAA AVHRR images were analyzed to prepare snow-related data of the model. Snow cover areas were extracted using channels 1, 3, and 4, and the snow depth was spatially interpolated using snowfall data of 11 ground meteorological stations. With the snowmelt parameters (snow cover area, snow water equivalent, and snow depth), the model was calibrated for 2 sets (2002–2003, 2004–2005), and verified for 2 sets (1997–1998 and 2001–2002) using the calibrated parameters. The average Nash–Sutcliffe efficiencies during the full year period (December to November) and snowmelt period (December to April) were 0.60 and 0.66, respectively. The future climate data of CCCma CGCM2 SRES A2 and B2 scenarios were adjusted and downscaled using change factor method. By the future impact of climate change, the annual dam inflows were projected to change maximum ?29.3 and ?30.4 % for 2090s A2 scenario and 2030s for B2 scenario, respectively. The future dam inflow increased in winter season (December to February) up to 222.0 %, while other periods decreased up to 54.8 %. The future snowmelt increased in December and January by the future temperature increase of 3.9 °C in minimum. The future snowmelt for the 2 months affected the dam inflows during the winter season. 相似文献
666.
667.
Woo Jung Kim Young Ok Kim Jin Hee Kim Bo-Hye Nam Dong-Gyun Kim Cheul Min An Jun Sik Lee Pan Soo Kim Hye Min Lee Joa-Sup Oh Jong Suk Lee 《Marine drugs》2016,14(1)
The ocean is a rich resource of flora, fauna, and food. A wild-type bacterial strain showing confluent growth on marine agar with antibacterial activity was isolated from marine water, identified using 16S rDNA sequence analysis as Pseudoalteromonas sp., and designated as strain M2. This strain was found to produce various secondary metabolites including quinolone alkaloids. Using high-resolution mass spectrometry (MS) and nuclear magnetic resonance (NMR) analysis, we identified nine secondary metabolites of 4-hydroxy-2-alkylquinoline (pseudane-III, IV, V, VI, VII, VIII, IX, X, and XI). Additionally, this strain produced two novel, closely related compounds, 2-isopentylqunoline-4-one and 2-(2,3-dimetylbutyl)qunoline-4-(1H)-one, which have not been previously reported from marine bacteria. From the metabolites produced by Pseudoalteromonas sp. M2, 2-(2,3-dimethylbutyl)quinolin-4-one, pseudane-VI, and pseudane-VII inhibited melanin synthesis in Melan-A cells by 23.0%, 28.2%, and 42.7%, respectively, wherein pseudane-VII showed the highest inhibition at 8 µg/mL. The results of this study suggest that liquid chromatography (LC)-MS/MS-based metabolite screening effectively improves the efficiency of novel metabolite discovery. Additionally, these compounds are promising candidates for further bioactivity development. 相似文献
668.
669.
Genetic diversity and population structure of Raffaelea quercus‐mongolicae,a fungus associated with oak mortality in South Korea 下载免费PDF全文
M.‐S. Kim P. A. Hohenlohe K.‐H. Kim S.‐T. Seo N. B. Klopfenstein 《Forest Pathology》2016,46(2):164-167
Raffaelea quercus‐mongolicae is a fungus associated with oak wilt and deemed to cause extensive oak mortality in South Korea. Since the discovery of this fungus on a dead Mongolian oak (Quercus mongolica) in 2004, the mortality continued to spread southwards in South Korea. Despite continued expansion of the disease and associated significant impacts on forest ecosystems, information is lacking about the origin and genetic diversity of R. quercus‐mongolicae. Restriction‐site‐associated DNA (RAD) sequencing was used to assess genetic diversity and population structure among five populations (provinces) of R. quercus‐mongolicae in South Korea. In total, 179 single nucleotide polymorphisms (SNPs) were identified among 2,639 RAD loci across the nuclear genome of the 54 R. quercus‐mongolicae isolates (0.0012 SNPs per bp), which displayed an overall low expected heterozygosity and no apparent population structure. The low genetic diversity and no apparent population structure among South Korean populations of this ambrosia beetle‐vectored fungus support the hypothesis that this fungus was introduced to South Korea. 相似文献