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671.
Today, over-consumption, pollution and resource depletion threaten sustainability. Waste management policies frequently fail to reduce consumption, prevent pollution, conserve resources and foster sustainable products. However, waste policies are changing to focus on lifecycle impacts of products from the cradle to the grave by extending the responsibilities of stakeholders to post-consumer management. Product stewardship and extended producer responsibility are two policies in use, with radically different results when compared for one consumer product, refrigerators. North America has enacted product stewardship policies that fail to require producers to take physical or financial responsibility for recycling or for environmentally sound disposal, so that releases of ozone depleting substances routinely occur, which contribute to the expanding the ozone hole. Conversely, Europe's Waste Electrical and Electronic Equipment (WEEE) Directive requires extended producer responsibility, whereby producers collect and manage their own post-consumer waste products. WEEE has resulted in high recycling rates of greater than 85%, reduced emissions of ozone-depleting substances and other toxins, greener production methods, such as replacing greenhouse gas refrigerants with environmentally friendly hydrocarbons and more reuse of refrigerators in the EU in comparison with North America. 相似文献
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674.
Aishwarya Arjunan Holly Bellerose Raul Torres Rotem Ben-Shachar Jodi D. Hoffman Brad Angle Robert Nathan Slotnick Brittany N. Simpson Andrea M. Lewis Pilar L. Magoulas Kelly Bontempo Jeanine Schulze Jennifer Tarpinian Jessica A. Bucher Richard Dineen Allison Goetsch Gabriel A. Lazarin Katherine Johansen Taber 《黑龙江环境通报》2020,40(10):1246-1257
Background
Disease severity is important when considering genes for inclusion on reproductive expanded carrier screening (ECS) panels. We applied a validated and previously published algorithm that classifies diseases into four severity categories (mild, moderate, severe, and profound) to 176 genes screened by ECS. Disease traits defining severity categories in the algorithm were then mapped to four severity-related ECS panel design criteria cited by the American College of Obstetricians and Gynecologists (ACOG).Methods
Eight genetic counselors (GCs) and four medical geneticists (MDs) applied the severity algorithm to subsets of 176 genes. MDs and GCs then determined by group consensus how each of these disease traits mapped to ACOG severity criteria, enabling determination of the number of ACOG severity criteria met by each gene.Results
Upon consensus GC and MD application of the severity algorithm, 68 (39%) genes were classified as profound, 71 (40%) as severe, 36 (20%) as moderate, and one (1%) as mild. After mapping of disease traits to ACOG severity criteria, 170 out of 176 genes (96.6%) were found to meet at least one of the four criteria, 129 genes (73.3%) met at least two, 73 genes (41.5%) met at least three, and 17 genes (9.7%) met all four.Conclusion
This study classified the severity of a large set of Mendelian genes by collaborative clinical expert application of a trait-based algorithm. Further, it operationalized difficult to interpret ACOG severity criteria via mapping of disease traits, thereby promoting consistency of ACOG criteria interpretation.675.
676.
The Microbial Assay for Risk Assessment (MARA) is an innovative system based on an array of 11 different microbial species freeze-dried in a 96-well micro-titre plate format. Developed for testing the toxicity of chemicals, mixtures and environmental samples, the assay employs species of a taxonomically diverse range. In addition to ten prokaryotic species, a eukaryote (yeast) is included in the range. The MARA's innate scope of a multi-dimensional test allows determination of toxicity based on a unique assay fingerprint or index, numerically expressed as the mean Microbial Toxic Concentration (MTC). The most significant potential of the test is in the additional inference that can be conveyed to the toxicity evaluation because of the presence of each of the constituent species. In view of the fact that conventional aquatic bioassays, like fish or cladoceran tests, are expensive and impractical, the MARA could provide a cost-effective solution for routine ecotoxicological testing. The performance of the MARA was evaluated to ascertain its capability and potential scope. Sensitivity to toxicants and different environmental samples was assessed. Evaluation included comparison with other tests: namely Microtox, invertebrate (Daphnia magna and Thamnocephalus platyurus) microbiotests, and respiration-inhibition and nitrification-inhibition tests. The most sensitive invertebrate test was found to be the T. platyurus microbiotest for three of the four metals tested. The LC(50) values for this test for Cd(ii), Cr(vi) and As(iii) were 0.2, 0.018 and 0.3 mg l(-1), respectively; and the corresponding most sensitive MARA species MTC values were 4.4, 2.8 and 17 mg l(-1), respectively. 相似文献
677.
Daniella Rogerson Anna Alkelai Jessica Giordano Madhulatha Pantrangi Meng-Chang Hsiao Chia-Ling Nhan-Chang Joshua E. Motelow Vimla Aggarwal David Goldstein Ron Wapner Carrie J. Shawber 《黑龙江环境通报》2023,43(6):703-716
Objective
Congenital lymphatic anomalies (LAs) arise due to defects in lymphatic development and often present in utero as pleural effusion, chylothorax, nuchal and soft tissue edema, ascites, or hydrops. Many LAs are caused by single nucleotide variants, which are not detected on routine prenatal testing.Methods
Demographic data were compared between two subcohorts, those with clinically significant fetal edema (CSFE) and isolated fetal edema. A targeted variant analysis of LA genes was performed using American College of Medical Genetics criteria on whole exome sequencing (WES) data generated for 71 fetal edema cases who remained undiagnosed after standard workup.Results
CSFE cases had poor outcomes, including preterm delivery, demise, and maternal preeclampsia. Pathogenic and likely pathogenic variants were identified in 7% (5/71) of cases, including variants in RASopathy genes, RASA1, SOS1, PTPN11, and a novel PIEZO1 variant. Variants of uncertain significance (VOUS) were identified in 45% (32/71) of cases. In CSFEs, VOUS were found in CELSR1, EPHB4, TIE1, PIEZO1, ITGA9, RASopathy genes, SOS1, SOS2, and RAF1.Conclusions
WES identified pathogenic and likely pathogenic variants and VOUS in LA genes in 51% of fetal edema cases, supporting WES and expanded hydrops panels in cases of idiopathic fetal hydrops and fluid collections. 相似文献678.
Symbion americanus was recently described as the second species in the phylum Cycliophora, living commensally on the American commercial lobster
Homarus americanus. A previous genetic analysis of American and European populations of cycliophorans suggested that haplotype divergence in
S. americanus was much greater than in its European counterpart S. pandora. This study examined the population structure and demographics of 169 individuals thought to belong to S. americanus collected from lobsters over 13 North American localities (Nova Scotia, Canada to Maryland, USA) between October 2003 and
January 2006. Cytochrome c oxidase subunit I sequence data clearly suggested the presence of three cryptic lineages in a species complex, often co-occurring
in the same lobster specimens. One of these lineages, named the “G” lineage, was represented by very few individuals and therefore
was excluded from subsequent statistical analyses. The other two sympatric lineages, named the “T” and “C” lineages, showed
different population structure and demography. Although limited geographic structure was found in the T lineage, the C lineage
showed higher nucleotide and haplotype diversity values, as well as more variation between localities. The data also indicated
that the T lineage underwent a recent population expansion, suggesting that the C and T lineages may have speciated in allopatry
but a subsequent population expansion may have been responsible for their current sympatric distribution. Studies on the anatomy
and ecology of the sympatric lineages of this species complex should provide further information on the identity of the holotype
of S. americanus, which currently cannot be ascribed to any of the three cryptic lineages. 相似文献
679.
Despite the importance of the gills in the acquisition of food by suspension-feeding bivalve mollusks, there is almost no
information on gill organogenesis. By means of a series of stereoscan electron micrographs, this paper describes gill development
in the Chilean oyster, Ostrea chilensis, from the brooded larval stages to 1-month-old spat. A single gill rudiment was observed on each side of the mantle at a
shell length of 320 μm, and the rudiments increased in number and size until the end of the brooding period. During metamorphosis
the gill filaments increased in number from 5 or 6 to between 7 and 9. The loss of the velum and the absence of functional
gill filaments during metamorphosis are consistent with previous observations of weight loss during this critical period of
the life history, because the newly settled juvenile lacks the ability to remove particles from suspension. The end of metamorphosis
(100% of spat with dissoconch edge) was reached 36 h after larval settlement, when the gill filaments began to grow cilia,
which increased in density and differentiated as the spat developed and acquired the capability of suspension-feeding, accounting
for the increase in body weight previously recorded during this stage. The larval rudiments gave rise to the inner demibranchs.
The outer demibranchs were observed 10 days after settlement, located between the inner demibranch and the mantle. In 1-month-old
spat, the gill did not show differentiation between primary and secondary filaments, indicating that the heterorhabdic condition
characteristic of adult oysters had yet to be attained.
Received: 11 December 1998 / Accepted: 21 August 2000 相似文献
680.
W.A Thompson C.S Holling D Kira C.C Huang I Vertinskf 《Journal of Environmental Economics and Management》1979,6(1):51-68
A major difficulty in choosing a forest management policy that regulates yearly spraying and logging levels is the fact that such a choice involves comparisons among risky alternatives. Practical and theoretical constraints often make the specification of a utility function for the system infeasible. This paper demonstrates that by making reasonable and easily verifiable assumptions about some properties of preference profiles of participants in the system, it is possible to produce an effective algorithm for forest policy evaluation. The method proposed and applied to the case of the New Brunswick forests consists of: (1) construction of a forest simulation to generate policy contingent distributions of outcomes, and (2) employment of stochastic dominance to identify a nondominated set of policies. 相似文献