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971.
Conventional theory for color matching is Kubelka-Munk, but it fails in some situations. New intelligent procedures such as neural networks could learn the behavior of a complex system and produce accurate prediction. This paper investigates the ability of MLP (multiple layer perceptron) neural network for color matching of cotton fabric. Three reactive dyes, namely Levafix Red CA, Levafix Yellow CA and Levafix Blue CA were used for experiments. The dyed samples were scanned and L * a * b * histogram were extracted. Different neural networks were trained and tested using L * a * b * histogram of fabric’s images and also L * a * b * values (D65, 10°) of fabrics. The results were encouraging. For neural networks including the L * a * b * histogram in input vector, colorants and their concentration were predicted with a mean square error (MSE) less than 10?5 and an average value of color difference (CMC (1:2)) less than 1.5 for approximately 80 % of testing data.  相似文献   
972.
Background: Endometriosis is a common chronic inflammation causing major problems including infertility. The role of omega-3 and omega-6 fatty acids as their potential anti-inflammatory effects in endometriosis needs to be further explored. The objective of this study was to compare serum phospholipid fatty acid profile in endometriosis patients with controls, and to explore the correlation of this profile with the severity of the disease. Methods: Sixty-four endometriosis patients and 74 control women, in reproductive age, participated in this study. Among the endometriosis patients, 19 cases were in stage I, 27 cases in stage II, 8 cases in stage III, and 10 cases in stage IV. Each patient underwent laparoscopy. Before surgery, 5 ml of blood was obtained. After extraction of the total lipids, serum total phospholipid fraction was isolated by thin layer chromatography. Fatty acid composition of the phospholipid fraction was determined by gas chromatography and the resulted profile was compared in endometriosis patients and controls. The profile was also compared in the endometriosis group based on the severity of disease. Results: Stearic acid was significantly lower in the endometriosis group as compared to controls (P= 0.030). No other fatty acid compositions were significantly different between patients and controls. Serum ratio of eicosapentaenoic acid (EPA) to arachidonic acid (AA) was in reasonable correlation with the severity of endometriosis (r = 0.34, P = 0.006). Conclusion: According to these findings, levels of fatty acids in serum total phospholipids seem not to be a marker for endometriosis, but the EPA to AA ratio was a relevant factor indicating severity of illness.Key Words: Endometriosis, Phospholipids, Omega-3 fatty acids  相似文献   
973.
974.
In this research work, multifunctional cotton fabric comprising of UV protection, superhydrophobicity and antibacterial activity has been developed using facile pad-dry-cure method. In the first step, the concentration of repellent chemical has been optimized. Then, formulations containing nanoparticles of ZnO or TiO2 along with optimized concentration of repellent chemical and organic-inorganic binder have been applied to cotton fabric followed by the evaluation of functional properties. The surface morphology and elemental composition of treated fabric has been characterized through SEM and EDX, respectively. The treated samples have shown promising UV protection, superhydrophobicity and antibacterial properties durable upto 20 washing cycles.  相似文献   
975.
INTRODUCTION: Oxidation of low density lipoprotein (LDL) has been strongly implicated in the phathogenesis of atherosclerosis. The use of oxidants in dietary food stuff may lead to the production of oxidized LDL and may increase both the development and the progression of atherosclerosis. The present work investigated the effects of some elements including: copper (Cu), iron (Fe), vanadium (V) and titanium (Ti) on in vitro LDL oxidation quantitatively. METHODS: The first LDL fraction was isolated from fresh plasma by single vertical discontinuous density gradient ultracentrifugation. The formation of conjugated dienes and thiobarbituric acid reactive substances and increase in electrophoretic mobility of LDL were monitored as markers of the oxidation of LDL. RESULTS: It was demonstrated that Cu, Fe, V and Ti exhibited strong oxidant activity in this respect (P<0.001). Oxidation of LDL in the presence of Cu was more and appeared to be in this order Cu>Fe>V>Ti. DISCUSSION: Cu, Fe, V and Ti are redox-active transition metals that may cause oxidative damage to lipids, proteins and DNA molecules. We suggest that these elements may also influence the oxidation of LDL in vivo, which could increase both the development and progression of atherosclerosis.  相似文献   
976.
Emiliania huxleyi is a single celled, marine phytoplankton with global distribution. As a key species for global biogeochemical cycling, a variety of strains have been amassed in various culture collections. Using a library consisting of 52 strains of E. huxleyi and an 'in house' enzyme screening program, we have assessed the functional biodiversity within this species of fundamental importance to global biogeochemical cycling, whilst at the same time determining their potential for exploitation in biocatalytic applications. Here, we describe the screening of E. huxleyi strains, as well as a coccolithovirus infected strain, for commercially relevant biocatalytic enzymes such as acid/alkali phosphodiesterase, acid/alkali phosphomonoesterase, EC1.1.1-type dehydrogenase, EC1.3.1-type dehydrogenase and carboxylesterase.  相似文献   
977.
姬松茸多糖提取工艺的优化   总被引:8,自引:0,他引:8  
对姬松茸子实体多糖提取的工艺条件中的多糖提取温度、提取时间、浸提液pH值3因子的最优化组合问题进行了定量研究,建立了具有良好预测性能的姬松茸多糖提取条件的模型,并利用回归模型对工艺条件的最优化组合,对各单因子要素的多糖得率及其交互作用进行了探讨。试验表明,当浸提温度为100℃、浸提时间为3h、浸提液pH值为6.3时多糖得率处于较高水平  相似文献   
978.
The effects of calcium (Ca) deficiency on cation uptake and concentration of xylem sap from tomato roots after excision of the aerial parts, were studied. The measurements were made on tomato plants grown on nutrient solutions with +Ca or without‐Ca, over a period of 48 hours. Calcium deficiency entailed a significant increase of the flux of xylem sap between the 6th and 14th hour on the first day after excision. In spite of the lack of Ca in the nutrient solution, the Ca concentration in xylem sap was unaffected in regard to that of excised roots with +Ca. The maintenance of the Ca concentration in xylem sap of plants grown on a Ca deficient solution was related to a reuse of the Ca from the apoplastic root stores. So, this regulation indicates a possible translocation of the Ca available in the root supply and a mobility of this element out of the roots only during the early stages of exposure to a Ca deficiency. The presence of NH4 + in xylem sap with both +Ca and‐Ca treatments confirms the nitrogenous reduction activity of tomato roots. The accumulation of free ammonium 24 h after excision in both xylem saps (+Ca and‐Ca) is likely to be evidence of an alteration process of protein synthesis which is related to the depletion of the root water soluble carbohydrate supply.  相似文献   
979.
It has been shown through various experimental works that the geometry of woven fabrics will change after it is released from looms due to the contraction forces resulting in changed structural geometry in their fully relaxed state. In this work, an appropriate three dimensional unit cell is proposed for 2/2 twill woven structure. The proposed model covers all angles and lengths between warp and weft yarns in the three dimensional unit cell of the structure in its fully relaxed state assuming straight line path and circular cross-section of yarns. At first, a theoretical solution for estimation of skewness angle in float region of 2/2 twill fabrics is proposed by defining the JJ ratio index to consider different amount of contraction in float and crimp region of unit cell. Then the proposed theory is extended to include the weave and skewness angle of yarns in crimp region of woven structures. By applying this theory, the skewness angle of 2/2 twill weaves will be incorporated in structural modelling of woven fabrics which can be used in predicting the thickness and areal mass of the 2/2 twill woven structures. Besides the confirmed validation of model in predicting the areal mass, the results for estimating the thickness of fabrics are in close agreement with the measured ones in the fabrics with worsted and coarse cotton yarns.  相似文献   
980.
The potato tuberworm, Phthorimaea operculella (Zeller), is an important insect pest of potato, Solanum tuberosum L., both in storage and in the field. In this research, tubers of eight commercial potato cultivars and four Iranian selections with equal weight and dormancy were exposed to 10 pairs of adult P. operculella in a climate chamber set at 25?±?1 °C, 65?±?5 % RH and total darkness. In a free-choice situation, oviposition was lower on 397082–2, Khavaran and Morene compared to the other germplasm that were exposed to adults of P. operculella. Number of mines per tuber, length of mines per tuber, time of development of larvae, number of pre-pupae produced per tuber, weight of pre-pupae and number of eggs developed in ovaries per female were counted and/or measured on each commercial cultivar and selection. There were fewer and shorter mines on tubers of 397082–2, Khavaran and Morene compared to the other potato germplasm. The number of pre-pupae produced per tuber and the weight of pre-pupae were lower when P. operculella was reared on tubers of 397082–2, Khavaran and Morene. Also the development, survival and fecundity were lower when P. operculella was reared on those same germplasm. Flesh firmness was negatively correlated with larval survival (r 2?=?0.87); in addition, the percentage of starch and macronutrient composition was low on these three germplasm. Thus, tuber flesh firmness of these germplasm could delay larval penetration and lower establishment 397082–2, Khavaran and Morene showed promising traits that can be integral component of potato breeding for resistance to P. operculella and pest management programs.  相似文献   
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