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Metabolic engineering is an integrating methodology of analysis and synthesis for the improvement of flux distribution of metabolic pathways in complicated bioprocesses, which are highly multi-hierarchical systems to extend from macroscopic to microscopic levels. Recent progress in metabolic engineering methodologies to improve metabolic pathways in microorganisms was reviewed with many studies in this paper. Metabolic flux distribution was analyzed under different environmental conditions, using a metabolic reaction model. The physiological states of microorganisms were understood by interpreting metabolic flux analysis (MFA). This analysis was also used for development of process operation and control strategy. Cell capability to form a targeted product was analyzed with a metabolic reaction model and linear programming (LP). The use of a 13C-enriched carbon source and nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GCMS) analyses of intracellular and extracellular metabolites enabled determination of a metabolic flux distribution more accurately than the flux distribution determined only by the metabolic reaction model, which involves not only metabolite balances but also energy and redox balances. The comparison of metabolic flux distributions between before and after genetic modification of cells yielded information on the mechanism of regulation of metabolic flux in microorganisms. Finally, integration of bioinformatics and metabolic engineering is discussed, and cyclic modification of the complex bionetwork and process development were emphasized.  相似文献
计算机视觉技术在海产品质量评估中的应用   总被引:1,自引:0,他引:1  
传统的海产品分类及质量检验主要是采用人工方法,靠肉眼进行判断,需耗费大量的人力,且劳动强度大、效率低。采用计算机视觉技术对海产品进行自动分类与质量评估可有效克服上述缺点。通过提取海产品的尺寸、形状、颜色、纹理等特征,结合预测模型,采用数字图像处理的方法可实现海产品的无接触、无损伤处理。文章分析基于计算机视觉技术的海产品分类及质量评估系统的构成,并通过实例分析阐述其具体实现方法,论证该方法的有效性。  相似文献
新疆特色干酪中乳酸菌的分离鉴定   总被引:1,自引:0,他引:1  
从新疆不同牧区采集工艺不同的干酪制品,对其中的乳酸菌进行分离纯化、生理生化性质试验和16S rRNA分析.结果表明,分离、纯化出的104株乳酸菌种,有82株为乳杆菌属(Lactobacillus),12株为肠球菌属(Enterococcus),10株为魏斯氏菌属(Weissella).利用16S rRNA序列同源分析和系统发育树分析对具有不同生理生化特性的代表菌株进行了分子鉴定,鉴定结果为TNM-2与干酪乳杆菌(Lactobacillus casei)、Y5-4与食窦魏斯氏菌(Weissella cibaria)、NS2-2与植物乳杆菌(Lactobacillus plantarum)的同源性达到100%,NM-2与瑞士乳杆菌(Lactobacillus helveticus)、Y1-1与马乳酒乳杆菌(Lactobacillus kefiranofaciens)、WG与耐久肠球菌(Enterococcus durans)的同源性达到99%.  相似文献
基于B/S结构的注塑机制造业仓库管理系统   总被引:1,自引:0,他引:1  
程功勋  李秀贤 《轻工机械》2009,27(2):107-109
通过分析注塑机制造业中传统仓库管理模式存在的问题和企业仓库管理的流程,提出了电子化的仓库管理处理流程,并采用.NET技术平台开发出了一套基于B/S结构的注塑机制造企业仓库管理系统,改善了企业仓库管理的效率。  相似文献
Lynette Kvasny 《》2006,9(2):160-181
In the US, community technology centers (CTC) are a policy response to facilitate the diffusion of information and communication technologies (ICT) to citizens who might otherwise lack access to these resources. The implicit assumption guiding CTC initiatives is that access to ICT will improve the life chances of the individuals who become involved in these centers. It is, however, prudent to empirically examine this assumption because the case for community technology interventions is somewhat weakened if the benefits of ICT use fail to accrue to those who are disadvantaged. Informed by Bourdieu's theory of reproduction, this study of a CTC initiative in an inner-city community explores the role of culture in reproducing digital inequality. Digital inequality reflects not only disparities in the structure of access to and use of ICT; it also reflects the ways in which longstanding social inequities shape beliefs and expectations regarding ICT and its impacts on life chances. While this initiative is considered successful in the sense that it provided access and basic computer literacy to residents lacking these resources, it represents a technology-centric fix to a problem that is deeply rooted in systemic patterns of spatial, political and economic disadvantage.  相似文献
彩色复制品中,颜色复制的准确与否是一个很重要的衡量与评价因素.设计灰梯尺作为视觉评价的标准进行主观评价,选用9个彩色复制中常见的色块,分别改变明度、饱和度与原图比较,进行主观评价.分析主观评价数据与测量数据(△Ea*b*、△E2000),不同的颜色对明度、饱和度的响应不同,不同的色差公式测量的结果也有很大的区别.  相似文献
隧道炉的节能与智能化是当今焙烤食品机械的一大主题。文中通过炉体、排潮系统的设计,远红外辐射元件的合理选择,各分区温度、带速的神经模糊控制,实现遂道炉的节能与智能化控制,完成各区温度的自动跟踪和带速的正确匹配,保证焙烤制品的高质量。  相似文献
传统的图像边缘检测算子一般都只能得到多像素宽度的边缘,这为后续的图像处理带来了一定困难。对大米二值图像的细化的程度直接影响颗粒特征的提取以及颗粒的识别,这也是开发大米检测系统软件部分又一个关键的课题。结合边缘走向趋势的估计技术以及对关键点判断的方法,提出一种新型的边缘细化算法—保持关键点的边缘细化算法。实验证明该算法能在保持边缘原有信息(连通和走向)的前提下,以较小的计算开销,满足物体骨架单像素宽为1的细化要求,实用性比较强。  相似文献
冯月亮  肖助明  李涛 《中国粮油学报》2006,21(6):151-154,173
针对大米检测图像中的脉冲噪声提出了一种新型的基于极值和噪声密度估计算法的自适应滤波算法,结合了EM算法和IMFLED算法的优点。实验表明该算法比现有的中值滤波去噪和保持物体的实际大小、边缘等许多重要细节的能力更强,特别在噪声密度比较高的情况。  相似文献
We describe a new high-throughput method of quantifying the structural properties of individual cell-sized liposomes. An internal aqueous solution of liposomes was labeled with a green fluorescent marker and the membrane with a red marker. The double-labeled liposomes were analyzed using flow cytometry, and the internal aqueous volume and lipid membrane volume of each liposome were measured. The experimental results indicate that both the internal aqueous and lipid membrane volumes positively correlate with the intensity of forward-scatter (FS) and side-scatter (SS) signals in a logarithmic scale. In addition, liposomes in 18 small areas gated by log(FS) and log(SS) were sorted by fluorescence-activated cell sorting (FACS), and observed by optical microscopy. Structural characteristics observed in the microscopy images of heterogeneous liposomes correlated with FACS data. Because this method does not employ any particular assumption about the shape and structure of liposomes, flow cytometry is a powerful tool for estimating the internal and membrane volumes of individual cell-sized liposomes with heterogeneous shapes and structures.  相似文献
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