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1.
A method of pattern combination analysis (PCA) is described. It consists of three categories: Pattern combination types (PCT), Triradial pattern combination types (PCT-tr) and Pattern combination ratios (PCR) with specific reference to ten digits and its several indices. The method has been used to investigate its validity in discriminating subdivided populations among the Yanadi tribe. The results show significant differences and a few unique pattern combinations in monomorphic and trimorphic frequencies and also in triradial pattern combination types, especially observed in IY population. Between the five Yanadi populations, the results obtained in all the categories of pattern combinations, in pattern combination indices, were in agreement with respect to the population structure variables of the five populations. The results also show clear sex differences especially observed in triradial pattern combination types (PCT-tr) and absence of tetramorphic patterns and ratios among females. This method can be further used for studying inheritance of the PCA, inbreeding effects and other issues of statistical distributional pattern and other theoretical and empirical aspects of anthropological genetics.  相似文献   

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The neutrophil-activating protein of Helicobacter pylori (HP-NAP) is a major antigen responsible for the generation of immune response in an infected individual. The cloning and expression of the gene corresponding to neutrophil-activating protein (NAP) were followed by process development for enhanced production and purification. The production process was developed in two parts. In the first part, some of the cultivation medium components (viz. carbon to nitrogen ratio, concentrations of sodium polyphosphate and magnesium sulphate) were optimized using the Taguchi robust experimental design. The intracellular NAP production level after 24 h of cultivation was considered as the target function or the dependent variable. There was a 76.8% increase in the NAP production level. Using this optimal medium composition obtained in the first part, the temperature of cultivation and the pH of cultivation medium were optimized in the second part. The NAP production level at hour 30 of cultivation was considered as the target function or the dependent variable. The optimal values for these two independent variables were 37.2 °C and 6.3 respectively. At this combination of temperature and pH, the theoretical maximum NAP production level was 1280 mg l–1. This optimal combination was verified experimentally and the NAP production level was found to be 1261 mg l–1. The optimization of the cultivation conditions resulted in a 61.5% increase in NAP production level. About a 2.91-fold overall increase in NAP production level at hour 24 of cultivation was achieved through process optimization.  相似文献   

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Penicillin acylase purification from an Escherichia coli crude extract using PEG 3350–sodium citrate aqueous two-phase systems (ATPS) was optimized. An experimental design was used to evaluate the influence of PEG, sodium citrate and sodium chloride on the purification parameters. A central composite design was defined centred on the previously found conditions for highest purification from an osmotic shock extract. Mathematical models for the partition coefficient of protein and enzyme, balance of protein and enzyme, yield and purification were calculated and statistically validated. Analysis of the contours of constant response as a function of PEG and sodium citrate concentrations for three different concentrations of NaCl revealed different effects of the three factors on the studied parameters. A maximum purification factor of 6.5 was predicted for PEG 3350, sodium citrate and NaCl concentrations of 15.1, 11.0 and 8.52% respectively. However, under these conditions the predicted yield was 61%. A better compromise between these two parameters can be found by superimposing the contour plots of the purification factor and yield for 10.3% NaCl. A region in the experimental space can be defined where the purification factor is always higher than 5.5 with yields exceeding 80%.  相似文献   

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Currently, the targeted treatment of tumor based on the tumor microenvironment is newly developed. Blood vessels are the key parts in the tumor microenvironment, which is taken as a new visible target for tumor therapy. Multiphoton microscopy (MPM), based on the second harmonic generation and two‐photon excited fluorescence, is available to make the label‐free analysis on the blood vessels in human gliomas. MPM can reveal the vascular morphological characteristics in gliomas, including vascular malformation, intense vascular proliferation, perivascular collagen deposition, perivascular lymphocytes aggregation and microvascular proliferation. In addition, the image analysis algorithms were developed to automatically calculate the perivascular collagen content, vascular cavity area, lumen area, wall area and vessel number. Thus, the vascular morphology, the perivascular collagen deposition and intense vascular proliferation degree can be further quantitatively characterized. Compared with the pathological analysis, the combination of MPM and image analysis has potential advantages in making a quantitative and qualitative analyzing on vascular morphology in glioma microenvironment. As micro‐endoscope and two‐photon fiberscope are technologically improved, this combined method will be a useful imaging way to make the real‐time research on the targeting tumor microenvironment in gliomas.  相似文献   

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A multi-objective optimization model of cascade reservoirs was developed to maximize the power generation and minimizie the appropriate ecological flow shortage index (AEFSI) downstream from the reservoir. Additionally, the non-dominated sorting genetic algorithm (NSGA-II) was used to search for multi-objective Pareto optimal solutions. The paper took the Three Gorges-Gezhouba cascade reservoirs as a case study. After validating the model, data from three typical years were used in the optimization. The results indicated that maximizing power generation by adjusting the optimal rules increased power generation by 1.07%, 0.91%, and 1.03% in normal, wet, and dry hydrological years, respectively, while increasing the AEFSI by 22.12%, 11.78%, and 14.67% (compared to real operations). The AEFSI was improved (decreased) by 21.90%, 10.27%, and 18.52% when the optimal rules favored the downstream ecology, but power generation decreased by 1.61%, 1.06%, and 2.29%, respectively, in the different hydrological years. Moreover, the results provide a set of well-distributed optimal solutions along the Pareto front that allow decision-makers to easily determine the best compromised solutions based on the trade-offs between the economic and ecological benefits. The results of this study provide guidance for decision-makers to improve the comprehensive benefits of the Three Gorges-Gezhouba cascade reservoirs.  相似文献   

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Three cytisine derivatives, (-)-(7R,9S)-1-phenyl-3-(cytisin-12-yl)propan-1-one (1), (-)-(7R,9S)-1-phenyl-2-(cytisin-12-yl)ethane (2), and (-)-(7R,9S)-1,2-bis(cytisin-12-yl)ethane (3), with different electronic and steric features have been characterized by X-ray analysis and theoretical calculations in order to evaluate how structural modulations affect the intrinsic binding affinity at the neuronal nicotinic receptors (nAChRs). The crystal structures of 1 and 2, which display comparable affinities, are characterized by the same conformation of the cytisine moiety with different orientations of the substituent at N2. In 3, two independent molecules have the pyridinone rings diversely oriented. This compound has a lower affinity with respect to 1 and 2, but it increases the expression of neuronal nAChRs. Compounds 1, 2, and 3 retain the key prerequisite of the classical pharmacophoric models, with sp(3)-N-atom--HBA distances close to the expected value, both in solid state and in solution (theoretical calculations), where, in contrast with the extended in the crystal state, a curled-up conformation has been found, though maintaining the N-substituent in equatorial position.  相似文献   

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A tris(2,2‐bipyridyl)ruthenium(II) (Ru(bpy)32+)‐based electrochemiluminescence (ECL) detection coupled with capillary electrophoresis (CE) method has been established for the sensitive determination of ephedrine for the first time. Under the optimized conditions [ECL detection at 1.15 V, 25 mmol/L phosphate buffer solution (PBS), pH 8.0, as running buffer, separation voltage 12.5 kV, 5 mmol/L Ru(bpy)32+ with 60 mmol/L PBS, pH 8.5, in the detection cell] linear correlation (r = 0.9987) between ECL intensity and ephedrine concentration was obtained in the range 6.0 × 10–8–6.0 × 10–6 g/mL. The detection limit was 4.5 × 10–9 g/mL (S:N = 3). The developed method was successfully applied to the analysis of ephedrine in human urine and the investigation of its interactions with three proteins, including bovine serum albumin (BSA), cytochrome C (Cyt‐C) and myoglobin (Mb). The number of binding sites and the binding constants between ephedrine and BSA, Cyt‐C and Mb were 8.52, 12.60, 10.66 and 1.55 × 104 mol/L, 6.58 × 103 mol/L and 1.59 × 104 mol/L, respectively. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

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多变量空间相关分析多基于时间序列数据,对数据时长与统计要求严格,空间非平稳性特征分析可以利用单期数据分析多变量之间的相关性。通过空间变系数回归模型分析了2006年和2011年的新疆伊犁地区降水量和温度对植被覆盖度指数影响的空间变化特征,利用局部线性地理加权回归(GWR)方法估计得到了回归系数曲面,揭示出变量间相互影响的空间异质性,同时利用线性回归最小二乘估计进行了对比。结果表明:(1)空间变系数回归模型可以用于变量间的空间相关分析;(2)局部线性GWR估计方法明显优于线性回归最小二乘估计;(3)拟合结果表明,伊犁地区降水量和温度对植被覆盖指数的影响具有显著的空间非平稳性特征;(4)模型估计误差是降水、气温之外的地形、地貌及人类活动等多种因素造成的,需进一步研究。方法可为具有空间非平稳性特征变量间空间相关性分析以及植被覆盖指数的空间模拟分布提供思路和方法。  相似文献   

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Background and aimHertwig’s Εpithelial Root Sheath (HΕRS) has a major function in the developing tooth roots. Earlier research revealed that it undergoes epithelial–mesenchymal transition, a vital process for the morphogenesis and complete development of the tooth and its surrounding periodontium. Few studies have demonstrated the role of HERS in cementogenesis through ΕMΤ. The background of this in-silico system biology approach is to find a hub protein and gene involved in the EMT of HERS that may uncover novel insights in periodontal regenerative drug targets.Materials and methodsThe protein and gene list involved in epithelial–mesenchymal transition were obtained from literature sources. The protein interaction was constructed using STRING software and the protein interaction network was analyzed. Molecular docking simulation checks the binding energy and stability of protein-ligand complex.ResultsResults revealed the hub gene to be DYRK1A(Hepcidin), and the ligand was identified as isoetharine. SΤRIΝG results showed a confidence cutoff of 0.9 in sensitivity analysis with a condensed protein interaction network. Overall, 98 nodes from 163 nodes of expected edges were found with an average node degree of 11.9. Docking results show binding energy of ?4.70, and simulation results show an RMSD value of 5.6 Å at 50 ns.ConclusionIsoetharine could be a potential drug for periodontal regeneration.  相似文献   

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