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人工湿地及其在工业废水处理中的应用   总被引:123,自引:2,他引:123  
论述了人工湿地污水处理技术的机理和优点,人工湿地利用基质、植物和微生物这个复合生态系统的物理、化学和生物的三重协调作用,通过过滤,吸附、共沉淀、离子交换,植物吸收和微生物分解来实现对废水的高效净化,同时通过营养物质和水分的生物地球化学循环,促进绿色植物生长并使其增产,实现废水的资源化与无害化;人工湿地污水处理系统具有出水水质稳定,对营养物质去除能力强,基建和运行费用低,技术含量低,维护管理方便,耐冲击负荷强,适于处理间歇排放的污水和具有美学价值等优点,该技术不仅能够在发展中国家和发达国家的城市生活污水处理中广泛应用,其在工业废水处理中的应用也正在不断受到重视,根据人工湿地在工业废水处理中的研究和应用现状,指出了人工湿地处理特殊工业废水的前景及今后的研究方向。  相似文献   

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Large-scale parallel measurement of whole-genome RNA expression is now possible with high-density arrays of cDNA or oligonucleotides. Using this technology efficiently will require the integration of other sources of biological information, such as gene identity, biomedical literature and biochemical pathway for a given gene. Such integration is essential to understand the cellular program of gene expression and the molecular physiology of an organism. Advances in microarray technology, and the expected rapid rise in microarray data will lead to new insight into fundamental biological problems such as the prediction of gene function from expression profiles and the identification of potential drug targets from biologically active compounds.  相似文献   

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In spite of much work, many of the properties of water remain puzzling. A fluctuating network of water molecules, with localised icosahedral symmetry, is proposed to exist derived from clusters containing, if complete, 280 fully hydrogen-bonded molecules. These are formed by the regular arrangement of identical units of 14 water molecules that can tessellate locally, by changing centres, in three-dimensions and interconvert between lower and higher density forms. The structure allows explanation of many of the anomalous properties of water including its temperature-density and pressure-viscosity behaviour, the radial distribution pattern, the presence of both pentamers and hexamers, the change in properties and 'two-state' model on supercooling and the solvation properties of ions, hydrophobic molecules, carbohydrates and macromolecules. The model described here offers a structure on to which large molecules can be mapped in order to offer insights into their interactions.  相似文献   

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Approximately 3% of the world population is infected by HCV, which represents a major global health challenge. Almost 400 different scientific reports present immunological data related to T cell and antibody epitopes derived from HCV literature. Analysis of all HCV-related epitope hosted in the Immune Epitope Database (IEDB), a repository of freely accessible immune epitope data, revealed more than 1500 and 1900 distinct T cell and antibody epitopes, respectively. The inventory of all data revealed specific trends in terms of the host and the HCV genotypes from which sequences were derived. Upon further analysis we found that this large number of epitopes reflects overlapping structures, and homologous sequences derived from different HCV isolates. To access and visualize this information we developed a novel strategy that assembles large sets of epitope data, maps them onto reference genomes and displays the frequency of positive responses. Compilation of the HCV immune reactivity from hundreds of different studies, revealed a complex and thorough picture of HCV immune epitope data to date. The results pinpoint areas of more intense reactivity or research activities at the level of antibody, CD4 and CD8 responses for each of the individual HCV proteins. In general, the areas targeted by the different effector immune functions were distinct and antibody reactivity was positively correlated with hydrophilicity, while T cell reactivity correlated with hydrophobicity. At the sequence level, epitopes frequently recognized by both T cell and B cell correlated with low variability, and our analysis thus highlighted areas of potential interest for practical applications. The human reactivity was further analyzed to pinpoint differential patterns of reactivity associated with acute versus chronic infection, to reveal the apparent impact of glycosylation on T cell, but not antibody responses, and to highlight a paucity of studies involved antibody epitopes associated with virus neutralization.  相似文献   

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The percentage contribution of heart rate ( f H) to change in oxygen consumption ( V o2) was examined in relation to body weight and across the metabolic scope of pike. Also the consequences of variability around the regression relating V o2 and f H for estimating V o2 were considered. The percentage contribution of f H was calculated using two equations, one that ignored and one that included an estimate for oxygen consumed by the gills and absorbed across the skin ( V o2s). Using both equations the percentage contribution of f H calculated using maximum and resting values for f H and V o2 decreased with weight of pike. The omission of V o2s, resulted in erroneously high estimates of the percentage contribution of f H for pike of any given weight. The omission of V o2s resulted in erroneously high estimates of the percentage contribution of f H over the region of the metabolic scope where f H is related linearly to V o2, whereas the equation that included V o2s resulted in the expected value of 100%. Assuming zero experimental error and under normoxic conditions, the 95% confidence limits for single estimates of V o2 from 30–60-min readings of heart rate are ±39% at a heart rate of 30 beats min −1. Averaged over longer periods the error decreases, and used over several days to estimate meal size the error is of the order of 1%.  相似文献   

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Recently, dramatic progress has been achieved in expanding the sensitivity, resolution, mass accuracy, and scan rate of mass spectrometers able to fragment and identify peptides through MS/MS. Unfortunately, this enhanced ability to acquire proteomic data has not been accompanied by a concomitant increase in the availability of flexible tools allowing users to rapidly assimilate, explore, and analyze this data and adapt to various experimental workflows with minimal user intervention. Here we fill this critical gap by providing a flexible relational database called PeptideDepot for organization of expansive proteomic data sets, collation of proteomic data with available protein information resources, and visual comparison of multiple quantitative proteomic experiments. Our software design, built upon the synergistic combination of a MySQL database for safe warehousing of proteomic data with a FileMaker‐driven graphical user interface for flexible adaptation to diverse workflows, enables proteomic end‐users to directly tailor the presentation of proteomic data to the unique analysis requirements of the individual proteomics lab. PeptideDepot may be deployed as an independent software tool or integrated directly with our high throughput autonomous proteomic pipeline used in the automated acquisition and post‐acquisition analysis of proteomic data.  相似文献   

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A comparison is made between existing mathematical models and experimental data that relate the reduction of the saturated hydraulic conductivity (K) of a porous medium to the porosity reduction caused by microbial growth. The models yielded a realistic prediction of a data set obtained with a model porous medium consisting of millimeter‐size glass spheres, but failed to predict the clogging behaviour observed in smaller‐than‐1‐mm sand. A new modelling approach, semi‐mechanistic in nature, is proposed that gives good predictions of fine sand media as well. It relaxes the assumption about uniformly‐thick biofilms by allowing a second arrangement to occur, i.e. discrete plugs filling the pore lumen. The new model requires input data on two intrinsic properties of the system, which renders it sufficiently flexible as to fit very different data sets. The two model parameters are Kmin, the minimum K value when all porosity is filled with microorganisms, and Bc, the biovolume fraction at which most cell detachment from biofilm occurs.  相似文献   

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As a result of recent radiobiological research it has become evident that the RBE of neurons can at low absorbed doses reach values that are substantially higher than the values of the quality factor (Q) currently adopted for radiation protection. There is theoretical and observational evidence that such high RBE values are the rule rather than the exception and that they apply to at least one radiation effect on humans. New values as well as different formulations are proposed for the factor that is employed in radiation protection to weight absorbed doses for their biological effectiveness.  相似文献   

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The combination of sequencing and post-sequencing experimental approaches produces huge collections of data that are highly heterogeneous both in structure and in semantics. We propose a new strategy for the integration of such data. This strategy uses structured sets of sequences as a unified representation of biological information and defines a probabilistic measure of similarity between the sets. Sets can be composed of sequences that are known to have a biological relationship (e.g. proteins involved in a complex or a pathway) or that share similar values for a particular attribute (e.g. expression profile). We have developed a software, BlastSets, which implements this strategy. It exploits a database where the sets derived from diverse biological information can be deposited using a standard XML format. For a given query set, BlastSets returns target sets found in the database whose similarity to the query is statistically significant. The tool allowed us to automatically identify verified relationships between correlated expression profiles and biological pathways using publicly available data for Saccharomyces cerevisiae. It was also used to retrieve the members of a complex (ribosome) based on the mining of expression profiles. These first results validate the relevance of the strategy and demonstrate the promising potential of BlastSets.  相似文献   

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It is difficult to name fossils which are intermediate between chronospecies or chronogenera in general paleontology. A possible solution is proposed for discussion: namely, to utilize bigeneric nomina to designate a group of fossils which are intermediate between two consecutive genera, and bispecific nomina to designate fossils which are intermediate between two consecutive species.  相似文献   

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《IRBM》2008,29(6):340-349
Falls affect, each year, tens of million of elderly people throughout the world. It can have immediate lethal consequences but also causes many disabling fractures and dramatic psychological consequences which reduce the independence of the person. Falls in the elderly is thus a major public health problem. The “early” detection of fall consequently raises the interest of searchers, as most of elderly fallers cannot return to a standing position on their own following a fall. It is also an interesting scientific problem because it is an ill-defined process. The goals of this study were to classify various approaches used to detect the fall and to point out the difficulty to compare the results of these studies, as there is currently no common evaluation benchmark.  相似文献   

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