Chromosome mosaicism and maternal cell contamination in chorionic villi

While chorionic villus sampling allows both early and rapid prenatal diagnosis of chromosome disorders, the accuracy of this technique has not been fully established. Maternal cell contamination and pseudomosaicism represent two major sources of diagnostic error. Combined use of both direct chromosome preparations and villus cultures is important in overcoming these problems. Direct preparations of villus tissue allow recognition of maternal cell contamination of villus cultures. Conversely, villus cultures yield higher resolution chromosomes and may be helpful in differentiating between true versus pseudomosaicism when two or more cell lines are identified in direct chromosome preparations. Preliminary data suggest that analysis of direct preparations from multiple individually processed villus fragments may also be of value in this regard. Until more experience is gained, mid-trimester amniocentesis should be offered to CVS patients when mosaicism is encountered.     

Effects of sample preparation on the measurement of organic carbon,hydrogen, nitrogen,sulfur, and oxygen concentrations in marine sediments

The elemental composition of marine sediment provides useful information for the study of environmental processes including biogeochemical cycling and contaminant partitioning. It is common practice to acidify marine sediment samples to remove carbonate before measuring the concentrations of organic carbon (C). To date, however the effects of acidification on the concentrations of hydrogen (H), nitrogen (N), sulfur (S) and oxygen (O) in marine sediments have not been explicitly addressed. Acidification may contaminate or alter the sediment samples and create experimental artifacts affecting the validity of resulting H/C, C/N and O/C ratios. The objective of this study was to quantify how various preparation techniques affect the measured concentrations of C, H, N, S and O in marine sediments. Effects of four different pretreatments: unacidified (whole), acidification by HCl vapor, acidification by direct addition of HCl, and combustion were evaluated using five marine sediments and a standard reference material. The magnitude of carbonate loss between the vapor and direct acidification treatments was evaluated using stable C isotope analysis. Carbonates were most effectively removed by direct addition of HCl; and our results agree with findings of other studies which found direct addition of HCl to be the most accurate method for measuring organic C. However, the acid treatments elevated the apparent concentration of H and O; and in a few cases concentrations of N and S were significantly affected by acidification. In general, combustion significantly reduced all elemental concentrations compared to the whole sample. Based on these results, we recommend analysis of the untreated whole sediment for determining N, H, O, and S.     

Evaluating the causal basis of ecological success within the scleractinia: an integral projection model approach

Many tropical corals have declined in abundance in the last few decades, and evaluating the causal basis of these losses is critical to understanding how coral reefs will change in response to ongoing environmental challenges. Motivated by the likelihood that marine environments will become increasingly unfavorable for coral growth as they warm and become more acidic (i.e., ocean acidification), it is reasonable to evaluate whether specific phenotypic traits of the coral holobiont are associated with ecological success (or failure) under varying environmental conditions including those that are adverse to survival. Initially, we asked whether it was possible to identify corals that are resistant or sensitive to such conditions by compiling quantitative measures of their phenotypic traits determined through empirical studies, but we found only weak phenotypic discrimination between ecological winners and losers, or among taxa. To reconcile this outcome with ecological evidence demonstrating that coral taxa are functionally unequal, we looked beyond the notion that phenotypic homogeneity arose through limitations of empirical data. Instead, we examined the validity of contemporary means of categorizing corals based on ecological success. As an alternative means to distinguish among functional groups of corals, we present a demographic approach using integral projection models (IPMs) that link organismal performance to demographic outcomes, such as the rates of population growth and responses to environmental stress. We describe how IPMs can be applied to corals so that future research can evaluate within a quantitative framework the extent to which changes in physiological performance influence the demographic underpinnings of ecological performance.     

Resuspension of contaminated field and formulated reference sediments Part I: Evaluation of metal release under controlled laboratory conditions

In aquatic systems where metal contaminated sediments are present, the potential exists for metals to be released to the water column when sediment resuspension occurs. The release and partitioning behavior of sediment-bound heavy metals is not well understood during resuspension events. In this study, the release of Cd, Cu, Hg, Ni, Pb and Zn from sediments during resuspension was evaluated using reference sediments with known physical and chemical properties. Sediment treatments with varying quantities of acid volatile sulfide (AVS), total organic carbon (TOC), and different grain size distributions were resuspended under controlled conditions to evaluate their respective effects on dissolved metal concentrations. AVS had the greatest effect on limiting release of dissolved metals, followed by grain size and TOC. Predictions of dissolved concentrations of Cd, Ni, Pb and Zn were developed based on the formulated sediment Σ_metal/AVS ratios with Σ_metal being the total sediment metal concentration. Predicted values were compared to measured dissolved metal concentrations in contaminated field sediments resuspended under identical operating conditions. Metal concentrations released from the field sediments were low overall, in most cases lower than predicted values, reflecting the importance of other binding phases. Overall, results indicate that for sulfidic sediments, low levels of the study metals are released to the dissolved phase during short-term resuspension.     

Bioremediation of trace organic compounds found in precious metals refineries' wastewaters: a review of potential options

Platinum group metal (PGM) refining processes produce large quantities of wastewater, which is contaminated with the compounds that make up the solvents/extractants mixtures used in the process. These compounds often include solvesso, beta-hydroxyxime, amines, amides and methyl isobutyl ketone. A process to clean up PGM refinery wastewaters so that they could be re-used in the refining process would greatly contribute to continual water storage problems and to cost reduction for the industry. Based on the concept that organic compounds that are produced biologically can be destroyed biologically, the use of biological processes for the treatment of organic compounds in other types of waste stream has been favoured in recent years, owing to their low cost and environmental acceptability. This review examines the available biotechnologies and their effectiveness for treating compounds likely to be contained in precious metal extraction process wastewaters. The processes examined include: biofilters, fluidized bed reactors, trickle-bed bioreactors, bioscrubbers, two-phase partitioning bioreactors, membrane bioreactors and activated sludge. Although all processes examined showed adequate to excellent removal of organic compounds from various gaseous and fewer liquid waste streams, there was a variation in their effectiveness. Variations in performance of laboratory-scale biological processes are probably due to the inherent change in the microbial population composition due to selection pressure, environmental conditions and the time allowed for adaptation to the organic compounds. However, if these factors are disregarded, it can be established that activated sludge and membrane bioreactors are the most promising processes for use in the treatment of PGM refinery wastewaters.     

Improving collaboration in the implementation of global biodiversity conventions

Eight conventions make up the biodiversity cluster of multilateral environmental agreements (MEAs) that provide the critical international legal framework for the conservation and sustainable use of nature. However, concerns about the rate of implementation of the conventions at the national level have triggered discussions about the effectiveness of these MEAs in halting the loss of biodiversity. Two main concerns have emerged: lack of capacity and resources and lack of coherence in implementing multiple conventions. We focused on the latter and considered the mechanisms by which international conventions are translated into national policy. Specifically, we examined how the Strategic Plan for Biodiversity 2011–2020 and the associated Aichi Biodiversity Targets have functioned as a unifying grand plan for biodiversity conservation. This strategic plan has been used to coordinate and align targets to promote and enable more effective implementation across all biodiversity-related conventions. Results of a survey of 139 key stakeholders from 88 countries suggests streamlining across ministries and agencies, improved coordination mechanisms with all relevant stakeholders, and better knowledge sharing between conventions could improve cooperation among biodiversity-related conventions. The roadmap for improving synergies among conventions agreed to at the 13th Convention on Biological Diversity's Conference of Parties in 2016 includes actions such as mechanisms to avoid duplication in national reporting and monitoring on conventions and capacity building related to information and knowledge sharing. We suggest the scientific community can actively engage and contribute to the policy process by establishing a science-policy platform to address knowledge gaps; improving data gathering, reporting, and monitoring; developing indicators that adequately support implementation of national plans and strategies; and providing evidence-based recommendations to policy makers. The latter will be particularly important as 2020 approaches and work to develop a new biodiversity agenda for the next decade is beginning.     

Nuclear War Investigation Related to a Limited Nuclear Battle with Emphasis on Agricultural Impacts in the United States

A limited battle involving the nuclear arsenals of India and Pakistan would have significant climatic impacts upon agricultural crop production in the United States; corn, soybeans, and winter wheat yields would be significantly reduced in the Corn Belt region of the US. The most severe impacts would occur during the second year after the modeled nuclear battle.     

The importance of Indigenous Peoples’ lands for the conservation of terrestrial mammals

Indigenous Peoples’ lands cover over one-quarter of Earth's surface, a significant proportion of which is still free from industrial-level human impacts. As a result, Indigenous Peoples and their lands are crucial for the long-term persistence of Earth's biodiversity and ecosystem services. Yet, information on species composition on these lands globally remains largely unknown. We conducted the first comprehensive analysis of terrestrial mammal composition across mapped Indigenous lands based on data on area of habitat (AOH) for 4460 mammal species assessed by the International Union for Conservation of Nature. We overlaid each species’ AOH on a current map of Indigenous lands and found that 2695 species (60% of assessed mammals) had ≥10% of their ranges on Indigenous Peoples’ lands and 1009 species (23%) had >50% of their ranges on these lands. For threatened species, 473 (47%) occurred on Indigenous lands with 26% having >50% of their habitat on these lands. We also found that 935 mammal species (131 categorized as threatened) had ≥ 10% of their range on Indigenous Peoples’ lands that had low human pressure. Our results show how important Indigenous Peoples’ lands are to the successful implementation of conservation and sustainable development agendas worldwide.     

超高效液相色谱/三重四极杆质谱联用(ACQUITY UPLC/Xevo TQ-S)检测蜂花粉中吡虫啉残留量

正在分析复杂环境样品中的痕量污染物时,通常会受到基质的严重干扰,使得在进行亚ng·g-1浓度水平检测时,所用仪器面临着必须满足灵敏度要求的挑战.杀虫剂暴露会对蜂群产生致死和亚致死效应,若要监控这些效应带来的影响则需要对蜜蜂和蜂产品中的杀虫剂水平进行可靠定量.某地区使用吡虫啉杀虫剂来应对昆虫的侵害,我们对该地区的蜜蜂样本及花粉产品进行了吡虫啉残留分析,花粉中平均含有20%蛋白质和6%总脂肪,并且还含有大量的维生素、脂肪酸、