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Water pollution control is presently one of the major thrust areas of scientific research. While coloured organic compounds
generally impart only a minor fraction of the organic load to wastewaters, their colour renders them aesthetically unacceptable.
Stringent regulating measures are coaxing industries to treat their waste effluents to increasingly high standards. Colour
removal, in particular, has recently become an area of major scientific interest as indicated by the multitude of related
research reports. During the past two decades, several decolourization techniques have been reported, few of which have been
accepted by some industries. There is a need to find alternative treatments that are effective in removing dyes and colourants
from large volume of effluents, which are cost-effective, like the biological or integrated systems. This article reviews
some of the widely used and most promising industrial wastewater decolourization methods. Data on decolourizing efficiencies
of different causative agents, obtained by means of different physical, chemical and biological methods are discussed. Further
a critical review is made on the various treatment methodologies and emerging technologies with a note on their advantages
and disadvantages. 相似文献
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Gregory E. MacDonald 《Critical Reviews in Plant Sciences》2004,23(5):367-380
Cogongrass is considered to be one of the ten most troublesome and problematic weedy species in the world. This species is found throughout tropical and subtropical regions, generally in areas disturbed by human activities. Over 100 common names have been associated with cogongrass, including japgrass, speargrass, alang-alang, and bladygrass. Although this species has several commercial uses, the problems associated with its weediness far outweigh most positive benefits. Cogongrass is a major impediment to reforestation efforts in southeast Asia, the number one weed in agronomic and vegetable production in many parts of Africa, and is responsible for thousands of hectares of lost native habitat in the southeastern U.S. Biologically, cogongrass possesses several features that foster its spread and persistence. Management efforts for cogongrass consist of an integrated approach with several control strategies. In agronomic production, the use of cover crops is widely successful, but incorporation into the overall production scheme is challenging. Success has been achieved with continuous deep tillage or chemical applications, but long-term eradication/suppression must employ sustainable revegetation strategies. 相似文献
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Marcello Barbieri 《Biosemiotics》2012,5(3):411-437
Systems Biology and the Modern Synthesis are recent versions of two classical biological paradigms that are known as structuralism and functionalism, or internalism and externalism. According to functionalism (or externalism), living matter is a fundamentally passive entity that owes its organization to external forces (functions that shape organs) or to an external organizing agent (natural selection). Structuralism (or internalism), is the view that living matter is an intrinsically active entity that is capable of organizing itself from within, with purely internal processes that are based on mathematical principles and physical laws. At the molecular level, the basic mechanism of the Modern Synthesis is molecular copying, the process that leads in the short run to heredity and in the long run to natural selection. The basic mechanism of Systems Biology, instead, is self-assembly, the process by which many supramolecular structures are formed by the spontaneous aggregation of their components. In addition to molecular copying and self-assembly, however, molecular biology has uncovered also a third great mechanism at the heart of life. The existence of the genetic code and of many other organic codes in Nature tells us that molecular coding is a biological reality and we need therefore a framework that accounts for it. This framework is Code biology, the study of the codes of life, a new field of research that brings to light an entirely new dimension of the living world and gives us a completely new understanding of the origin and the evolution of life. 相似文献
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Ecology is being introduced to Evolutionary Developmental Biology to enhance organism-, population-, species-, and higher-taxon-level
studies. This exciting, bourgeoning troika will revolutionise how investigators consider relationships among environment,
ontogeny, and phylogeny. Features are studied (and even defined) differently in ecology, development, and evolution. Form
is central to development and evolution but peripheral to ecology. Congruence (i.e., homology) is applied at different hierarchical
levels in the three disciplines. Function is central to ecology but peripheral to development. Herein, the supercategories
form (‘isomorphic’ or ‘allomorphic’), congruence (‘homologous’ or ‘homoplastic’), and function (‘adaptive’ or ‘nonadaptive’)
are combined with two developmental mode (i.e., growth) categories (‘conformational’ or ‘nonconformational’) to provide a
16-class system for analysing features in studies in which ecology, development, and evolution are integrated. 相似文献
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Dual targeting of a nuclearly encoded protein into two different cell organelles is an exceptional event in eukaryotic cells. Yet, the frequency of such dual targeting is remarkably high in case of mitochondria and chloroplasts, the two endosymbiotic organelles of plant cells. In most instances, it is mediated by “ambiguous” transit peptides, which recognize both organelles as the target. A number of different approaches including in silico, in organello as well as both transient and stable in vivo assays are established to determine the targeting specificity of such transit peptides. In this review, we will describe and compare these approaches and discuss the potential role of this unusual targeting process. Furthermore, we will present a hypothetical scenario how dual targeting might have arisen during evolution. 相似文献
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Angular transformation has been widely used to analyze proportions or percentages in ecology. A new type of artifact can arise by applying angular transformation to proportions or percentages. Proportions with the same mean or expected value, but with different sample sizes (denominator of proportions), have different means or expected values after this transformation. Overdispersion causes a larger deviation of the expected value after the transformation. Angular transformation should be avoided unless the sample size (denominator of proportions) is the same for all the proportions analyzed. 相似文献
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A brief history of Rubisco (ribulose bisphosphate carboxylase oxygenase) research and the events leading to the discovery
and initial characterization of Rubisco activase are described. Key to the discovery was the chance isolation of a novel Arabidopsis photosynthesis mutant. The characteristics of the mutant suggested that activation of Rubisco was not a spontaneous process
in vivo, but involved a heritable factor. The search for the putative factor by 2D electrophoresis identified two polypeptides, genetically
linked to Rubisco activation, that were missing in chloroplasts from the mutant. An assay for the activity of these polypeptides,
which were given the name Rubisco activase, was developed after realizing the importance of including ribulose bisphosphate
(RuBP) in the assay. The requirement for ATP and the subsequent identification of activase as an ATPase came about fortuitously,
the result of a RuBP preparation that was contaminated with adenine nucleotides. Finally, the ability of activase to relieve
inhibition of the endogenous Rubisco inhibitor, 2-carboxyarabinitol 1-phosphate, provided an early indication of the mechanism
by which activase regulates Rubisco.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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