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101.

1. 1. The purposes of this study are to find out the arrangement effects on the vapor pressure gradient across the cotton–nylon double layer and to elucidate changes in the vapor pressure gradient when an additional third layer covers the double layer.

2. 2. Model tests for single, double and triple layer system and wear test for triple layer clothing were conducted.

3. 3. It was found that up to the second layer, dryness of innermost microclimate could be maintained when cotton faced the skin (C/N).

4. 4. However, when more permeable and hydrophobic third layer (UWF) covers the double layer, the microclimate of C/N is no longer drier than N/C.

5. 5. When nylon is exposed to the skin, a larger drop in vapor pressure across the first two layers occurred for both model and wear test.

6. 6. The innermost microclimate was not necessarily kept dry when the outermost layer dissipated more moisture due to the inefficient distribution of moisture.

Author Keywords: Vapor pressure; microclimate; layer arrangement; cotton; nylon  相似文献   

102.
Cryptobia salmositica (pathogenic and vaccine strains), Cryptobia bullocki (pathogenic), and Cryptobia catostomi (nonpathogenic) have similar oxygen consumption rates (0.17 +/- 0.01 nm O2/10(6) parasites). Incubation with sodium azide (5 microliters of a 1-M solution to 1 ml of parasite suspension, i.e., a 5-mM final concentration) reduced the oxygen consumption by approximately 4.5-fold. Motility of the parasites was also greatly reduced in sodium azide. The oxygen consumption and motility of the parasites returned to preazide treatment levels when the azide was removed even after 24 hr of incubation in sodium azide. The activities of hexokinase, pyruvate kinase, and cytochrome C oxidase were not detected in the 3 species of Cryptobia.  相似文献   
103.
Trypanosoma catostomi was found in 36.2% of 558 white suckers (Catostomus commersoni) from Ontario, Canada. The abundance of Actinobdella inequiannulata was 35% (68 leeches/197 suckers examined for leeches). The susceptibility of 3 species of leeches (Hemiclepsis marginata, Desserobdella phalera, and A. inequiannulata) and 7 species of fishes (C. commersoni, Amia calva, Anguilla rostrata, Ictalurus nebulosus, Oncorhynchus mykiss, Perca flavescens, and Esox lucius) to infection with T. catostomi was examined. Metatrypanosomes were found in the crop and proboscis sheath of 13 of 21 A. inequiannulata and in the crop of 10 of 12 H. marginata and 1 of 21 D. phalera. Only flagellates from A. inequiannulata were infective to C. commersoni. Cultured T. catostomi infected C. commersoni and A. calva but not any other fish species. Laboratory-reared C. commersoni were more susceptible than wild-caught specimens. Cultured Trypanosoma phaleri did not infect its natural host, A. calva. Host specificity should be established experimentally before a specific diagnosis is made. Cultures may be useful in simulating factors that affect development in the vector.  相似文献   
104.
The relationships between increasing nitrogen fertilization and growth, maximum CO2 assimilation and the initial slope of the CO2 response curve were studied in 2 ecotypes of wild strawberry, Fragaria chiloensis (L.) Duchn. Nitrogen accumulation of CA11, an ecotype from a low-nutrient dune site, was greater at all nitrogen concentrations than that of RCP37, an ecotype from a higher-nutrient strand site. Maximum CO2 assimilation, total Rubisco activity, dry weight, and initiation of leaves and crowns were higher in CAI1 than RCP37 as nitrogen treatment was increased from 0 to 200 mg l-1, whereas these parameters were lower in CAl1 when fertilized at 300 mg T1, but not in RCP37. The mean leaf area of CA11 was greater than RCP37 when grown with no supplemental nitrogen, but mean leaf area of the 2 lines was similar under nitrogen fertilization. Maximum CO2 assimilation and carboxylation efficiency increased with increasing leaf nitrogen in both clones. At equivalent concentrations of leaf nitrogen, RCP37 had higher CO2 assimilation and carboxylation efficiency than CA11 and the difference between the 2 clones increased as ieaf nitrogen increased. Thus, RCP37 had a higher photosynthetic nitrogen use efficiency than CA11. However, at a given applied nitrogen level, CA11 allocated more nitrogen to a unit of leaf area so that photosynthetic rates were higher than RCP37, except at the highest application of 300 mg l-1. The high nitrogen accumulation capacity and resource allocation to fruiting structures (crowns) in CA11 leads us to suggest that this clone may possess genes that could increase fruit yield in cultivated strawberry.  相似文献   
105.
Suppression subtractive hybridization was carried out to enrich gene fragments over-expressed in rice leaves by subtraction to rice roots, from which two identical cDNA fragments were identified to encode putative phosphoenolpyruvate carboxylase. Then the corresponding full-length cDNA (Osppc) is isolated by RT-PCR and sequenced, which indicates an open reading frame of 2895bp is contained. Its deduced protein is encoded in 10 exons and shows high similarity to many other plant PEPCs. Comparing with maize and bacterial PEPCs, it is revealed that OSPPC shares many conserved domains and active sites that responsible for the structure, activity and regulation of this enzyme. Phylogenetic analysis demonstrates that OSPPC is grouped with C3 form PEPCs of wheat, maize and sorghum, which is consistent with the classification of rice. And a putative promoter element is predicted with DOF binding box, CAAT box and TATA box in the 5'-flanking sequence of Osppc gene. Moreover, Quantitative RT-PCR analyses are performed in hybrid rice and its parents, which show that Osppc is specifically expressed in leaf including leaf vein and sheath.  相似文献   
106.
The crystal structures of Streptomyces diastaticus No. 7 strain M1033 xylose isomerase (SDXyI) have been analysed and refined at 0.19nm. The crystal space group is I222, with unit cell dimensions of a=9.884 ran, b=9.393nm and c=8.798nm. Based on the coordinates of the Streptomyces rubiginosus xylose isomerase (SRXyI), the initial model of SDXyl was built up by the dose packing analysing and R-factor searching and refined by PROLSQ to a final R-factor of 0.177 with the rms deviations of bond lengths and bond angles of 0.001 9nm and 2.1°, respectively. No significant global conformation change existed between SRXyI and SDXyI except the local conformation in the active site.  相似文献   
107.
Rice is a leading grain crop and the staple food for over half of the world population. Rice is also an ideal species for genetic and biological studies of cereal crops and other monocotyledonous plants because of its small genome and well developed genetic system. To facilitate rice genome analysis leading to physical mapping, the identification of molecular markers closely linked to economic traits, and map-based cloning, we have constructed two rice bacterial artificial chromosome (BAC) libraries from the parents of a permanent mapping population (Lemont and Teqing) consisting of 400 F9 recombinant inbred lines (RILs). Lemont (japonica) and Teqing (indica) represent the two major genomes of cultivated rice, both are leading commercial varieties and widely used germplasm in rice breeding programs. The Lemont library contains 7296 clones with an average insert size of 150 kb, which represents 2.6 rice haploid genome equivalents. The Teqing library contains 14208 clones with an average insert size of 130 kb, which represents 4.4. rice haploid genome equivalents. Three single-copy DNA probes were used to screen the libraries and at least two overlapping BAC clones were isolated with each probe from each library, ranging from 45 to 260 kb in insert size. Hybridization of BAC clones with chloroplast DNA probes and fluorescent in situ hybridization using BAC DNA as probes demonstrated that both libraries contain very few clones of chloroplast DNA origin and are likely free of chimeric clones. These data indicate that both BAC libraries should be suitable for map-based cloning of rice genes and physical mapping of the rice genome.  相似文献   
108.
本文用LN及含其活性位点序列的合成肽段cYIGSR和RGDS对小鼠EPC细胞与LN的相互作用机制进行研究。结果表明:合成肽段cYIGSR和RGDS能促进EPC粘附并具协同效应。cYIGSR还能促进EPC扩展与次生TGCs迁移。LNA链上RGD和B_1链上YIGSR两个活性位点协同地参与了LN对EPC的粘附、扩展以及次生TGCs的迁移的促进作用。cY R合用不能完全竞争性抑制EPC与LN的结合,说明还有其他作用位点存在。  相似文献   
109.
Summary Chlorella vulgaris UTEX259 was cultivated using two different methods of gas supply. In one method the CO2 concentration in bubbled gas was held constant and in the other method it was increased gradually. Algal growth was almost linear after a short period of lag phase in both methods. With the constant CO2 concentration, the CO2 fixation rate in the linear growth phase decreased over 10%(v/v) CO2, while the rate increased up to 6% CO2. However, the rate was enhanced by using the latter incremental increase method, especially under a higher concentration of CO2. The maximum rate of CO2 fixation was 52 mg CO2/l·h at 20% CO2 during the gradual increase of CO2 concentration.  相似文献   
110.
Most higher plants have complex genomes containing large quantities of repetitive DNA interspersed with low-copy-number sequences. Many of these repetitive DNAs are mobile and have homology to RNAs in various cell types. This can make it difficult to identify the genes in a long chromosomal continuum. It was decided to use genic sequence conservation and grass genome co-linearity as tools for gene identification. A bacterial artificial chromosome (BAC) clone containing sorghum genomic DNA was selected using a maize Adh1 probe. The 165 kb sorghum BAC was tested for hybridization to a set of clones representing the contiguous 280 kb of DNA flanking maize Adh1. None of the repetitive maize DNAs hybridized, but most of the low-copy-number sequences did. A low-copy-number sequence that did cross-hybridize was found to be a gene, while one that did not was found to be a low-copy-number retrotransposon that was named Reina. Regions of cross-hybridization were co-linear between the two genomes, but closer together in the smaller sorghum genome. These results indicate that local genomic cross-referencing by hybridization of orthologous clones can be an efficient and rapid technique for gene identification and studies of genome organization.  相似文献   
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