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31.
Spunbonding is one of the most widely used processing techniques to convert polymers into nonwoven fabrics. metallocene-catalyzed polypropylene is becoming more and more important. A study was carried out to understand the development of structure and properties of a metallocene-catalyzed isotactic polypropylene during spunbonding. This research was conducted using the Reicofil spunbond line at the University of Tennessee, Knoxville. The filaments at three different throughput rates were studied for tensile properties and for structural features by birefringence, X-ray diffraction, and thermal measurements. The fabrics produced at different process conditions were tested for various mechanical properties. The failure mechanism of the fabrics at different bonding temperatures was studied using the scanning electron microscope. The results are compared with a conventional polypropylene processed under similar conditions. The results showed that the mPP produced fabrics with better strength and elongation at comparable processing conditions. Also, failure mechanisms were found to be different for the fabrics produced from the two polymers, which are due to differences in the produced structures. 相似文献
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Santhosh Kumar Vankayala Ramaiah Roman Günthner Maciej Lech Hans-Joachim Anders 《International journal of molecular sciences》2013,14(7):13213-13230
The cell type-, organ-, and species-specific expression of the Toll-like receptors (TLRs) are well described, but little is known about the respective expression profiles of their accessory molecules. We therefore determined the mRNA expression levels of LBP, MD2, CD36, CD14, granulin, HMGB1, LL37, GRP94, UNC93b1, TRIL, PRAT4A, AP3B1, AEP and the respective TLRs in human and mouse solid organs. Humans and mice displayed significant differences between their respective mRNA expression patterns of these factors. In addition, the expression profiles in transient tissue inflammation upon renal ischemia-reperfusion injury, in spleens and kidneys from mice with lupus-like systemic autoimmunity, and in progressive tissue fibrosis upon unilateral ureteral obstruction were studied. Several TLR co-factors were specifically regulated during the different phases of these disease entities, suggesting a functional involvement in the disease process. Thus, the organ- and species-specific expression patterns need to be considered in the design and interpretation of studies related to TLR-mediated innate immunity, which seems to be involved in the tissue injury phase, in the phase of tissue regeneration, and in progressive tissue remodelling. 相似文献
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Bei‐Zhong Han Jia‐Huai Wang Frans M Rombouts MJ Robert Nout 《Journal of the science of food and agriculture》2003,83(9):899-904
Sufu is made by solid state fungal fermentation (using Actinomucor elegans) of tofu, followed by salting and maturation in dressing mixtures containing salt, alcohol and various other ingredients. NaCl in dressing mixtures strongly affected the changes in textural properties and the hydrolysis of protein and lipid of sufu. Higher salt contents (14% w/w) resulted in increased hardness (+100%) and elasticity (+18%) and reduced adhesiveness (?30%). Hardness and elasticity could be used to judge the extent of sufu ripening. SDS‐PAGE showed the disappearance of all protein subunits at 80 and 110 g kg?1 salt content; however, some protein subunits were still detectable at 140 g kg?1 salt content after 60 days of ripening. Higher ratios of free amino nitrogen to total nitrogen (FAN/TN = 0.4–0.45) and free amino acids to crude protein (FAA/CP = 0.24–0.26) were observed in sufu with lower (80 g kg?1) salt content. FAN/TN and FAA/CP in white sufu (obtained with dressing mixtures containing only salt and alcohol) were higher than those in red sufu (obtained with dressing mixtures containing angkak or kojic red rice) owing to different dressing mixture compositions. Increases in free fatty acids (FFA) were also observed during ripening. FFA levels in sufu with lower salt content increased rapidly during the first 30–40 days and then increased slowly, probably resulting from the formation of fatty acid esters. Lowering the salt content (80 g kg?1) can shorten the ripening time to 40 days, which is of benefit to manufacturers. However, sufu will spoil, ie undergo souring, during the ripening stage at salt contents of 50 g kg?1 or lower. Copyright © 2003 Society of Chemical Industry 相似文献
34.
De-duplication using biometrics has gained much attention from research communities as it provides a unique identity for each and every individual among the large population.De-duplication is the process of removing the instances of multiple enrollments by the same person using the person’s biometric data.An important issue in the large-scale de-duplication applications is the speed of matching and the accuracy of the matching because the number of persons to be enrolled runs into millions.This paper presents an efficient method to improve the accuracy of fingerprint de-duplication in de-centralized manner.De-duplication accuracy decreases because of the noise present in the data,which would cause improper slap fingerprint segmentation.In this paper,an attempt is made to remove the noise present in the data by using binarization of slap fingerprint images and region labeling of desired regions with 8-adjacency neighborhood.The distinct feature of this technique is to remove the noise present in the data for an accurate slap fingerprint segmentation and improve the de-duplication accuracy.Experimental results demonstrate that the fingerprint segmentation rate and de-duplication accuracy are improved significantly. 相似文献
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The adult cuticular wing of Drosophila is covered by an array of distally pointing hairs that reveals the planar polarity of the wing. We report here that mutations in dachsous disrupt this regular pattern, and do so by affecting frizzled signaling. dachsous encodes a large membrane protein that contains many cadherin domains and dachsous mutations cause deformed body parts. We found that mutations in dachsous also result in a tissue polarity phenotype that at the cellular level is similar to frizzled, dishevelled and prickle, as many cells form a single hair of abnormal polarity. Although their cellular phenotype is similar to frizzled, dishevelled and prickle, dachsous mutant wings display a unique and distinctive abnormal hair polarity pattern including regions of reversed polarity. The development of this pattern requires the function of frizzled pathway genes suggesting that in a dachsous mutant the frizzled pathway is functioning - but in an abnormal way. Genetic experiments indicated that dachsous was not required for the intracellular transduction of the frizzled signal. However, we found that dachsous clones disrupted the polarity of neighboring wild-type cells suggesting the possibility that dachsous affected the intercellular signaling function of frizzled. Consistent with this hypothesis we found that frizzled clones in a dachsous mutant background displayed enhanced domineering non-autonomy, and that the anatomical direction of this domineering non-autonomy was altered in regions of dachsous wings that have abnormal hair polarity. The direction of this domineering nonautonomy was coincident with the direction of the abnormal hair polarity. We conclude that dachsous causes a tissue polarity phenotype because it alters the direction of frizzled signaling. 相似文献
37.
R Wikaningrum J Highton A Parker M Coleman PA Hessian PJ Roberts-Thompson MJ Ahern MD Smith 《Canadian Metallurgical Quarterly》1998,41(10):1783-1797
OBJECTIVE: To investigate the production of proinflammatory cytokines and expression of cell adhesion molecules in the rheumatoid nodule. METHODS: Cytokine content (tumor necrosis factor alpha [TNFalpha], interleukin-1beta [IL-1beta], and IL-1 receptor antagonist [IL-1Ra]), at the messenger RNA (mRNA) and protein levels, and cell adhesion molecule expression were studied in 16 rheumatoid nodules and 6 synovial membranes. RESULTS: Macrophages in the rheumatoid nodules contained TNFalpha, IL-1beta, and IL-1Ra mRNA and protein, particularly in perivascular cells of the stroma and in the palisading layer. All cell adhesion molecules studied were expressed in both the rheumatoid nodules and synovial membranes, with increased expression of E-selectin in the rheumatoid nodule compared with the synovial membrane, and with the absence of vascular cell adhesion molecule 1 expression on cells of the palisading layer in the rheumatoid nodule. CONCLUSION: The presence of similar proinflammatory cytokines and cell adhesion molecules in the rheumatoid nodule and synovial membrane suggests that similar pathogenic processes result in the chronic inflammation and tissue destruction in these lesions. 相似文献
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