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Environmental Science and Pollution Research - The aim of this study was to investigate the uptake of four beta-blockers by the model plant Lepidium sativum (garden cress) and their possible...  相似文献   
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Genetic diversity within species represents a fundamental yet underappreciated level of biodiversity. Because genetic diversity can indicate species resilience to changing climate, its measurement is relevant to many national and global conservation policy targets. Many studies produce large amounts of genome-scale genetic diversity data for wild populations, but most (87%) do not include the associated spatial and temporal metadata necessary for them to be reused in monitoring programs or for acknowledging the sovereignty of nations or Indigenous peoples. We undertook a distributed datathon to quantify the availability of these missing metadata and to test the hypothesis that their availability decays with time. We also worked to remediate missing metadata by extracting them from associated published papers, online repositories, and direct communication with authors. Starting with 848 candidate genomic data sets (reduced representation and whole genome) from the International Nucleotide Sequence Database Collaboration, we determined that 561 contained mostly samples from wild populations. We successfully restored spatiotemporal metadata for 78% of these 561 data sets (n = 440 data sets with data on 45,105 individuals from 762 species in 17 phyla). Examining papers and online repositories was much more fruitful than contacting 351 authors, who replied to our email requests 45% of the time. Overall, 23% of our email queries to authors unearthed useful metadata. The probability of retrieving spatiotemporal metadata declined significantly as age of the data set increased. There was a 13.5% yearly decrease in metadata associated with published papers or online repositories and up to a 22% yearly decrease in metadata that were only available from authors. This rapid decay in metadata availability, mirrored in studies of other types of biological data, should motivate swift updates to data-sharing policies and researcher practices to ensure that the valuable context provided by metadata is not lost to conservation science forever.  相似文献   
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Flax (Linum ustitatissimum L.) is the source of natural fibers that provides biobased products for a variety of existing markets, but considerable processing and cleaning is required. Flax fibers, and bast fibers generally, are produced in the outer regions of the stem between bark and inner core tissues and require retting, which is the microbial separation of fiber from nonfiber tissues, as the first and most limiting stage of processing. Enzyme retting offers a method to overcome disadvantages of the current method, i.e., dew-retting, for high- and consistent-quality fibers with tailored properties for specific applications. Using chemical analyses, microscopy, and microspectroscopy, sites of carbohydrates, aromatics, and waxes plus cutins were identified in flax stems and their relationship to effective enzyme retting determined. Aromatics occur mostly in the inner, core tissues, with the fibers containing only small amounts located sporadically in cell corners of fiber bundles. Therefore, effective retting using enzymes to separate the aromatic-containing tissues from the fibers, but not to degrade aromatic compounds per se, is required. Waxes and cutin in the epidermal regions are effective barriers to enzyme penetration, and mechanical disruption facilitates enzyme penetration into the stems. Pectinases, with chelators to remove Ca++ and destabilize pectin molecules, remove matrix compounds holding fibers within the stem and have been used in effective formulations to ret flax stems.  相似文献   
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