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21.
This paper summarizes some personal impressions of the 7th conference of the International Complex Systems Society, co-organized with “Future Earth”, held in Stockholm on August 24–26, 2017. The main point is that it is urgent and important to consider the sustainability conundrum as long-term, society-driven one, and to place societal dynamics at the core of how we, as a global society, came to this point, how ongoing dynamics are driving us towards a tipping point, and which role the Information and Communication Technology revolution plays in that process. A much wider involvement of the social sciences is essential. This also requires major changes in our thinking about sustainability—we need to develop an approach in which change is the natural state of affairs and societies attempt to impose stability on the dynamics involved. We need to focus on learning from the past, about the present, but above all for the future. And we need to shift from an entity-focused approach to a relational one, which pays more attention to contexts and networks. Other issues raised by such a shift in our thinking are about the role of science, the adoption of complex systems approaches and a few others that the paper points to.  相似文献   
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Objective

We performed a 1-year evaluation of a novel strategy of simultaneously analyzing single nucleotide variants (SNVs), copy number variants (CNVs) and copy-number-neutral Absence-of-Heterozygosity from Whole Exome Sequencing (WES) data for prenatal diagnosis of fetuses with ultrasound (US) anomalies and a non-causative QF-PCR result.

Methods

After invasive diagnostics, whole exome parent-offspring trio-sequencing with exome-wide CNV analysis was performed in pregnancies with fetal US anomalies and a non-causative QF-PCR result (WES-CNV). On request, additional SNV-analysis, restricted to (the) requested gene panel(s) only (with the option of whole exome SNV-analysis afterward) was performed simultaneously (WES-CNV/SNV) or as rapid SNV-re-analysis, following a normal CNV analysis.

Results

In total, 415 prenatal samples were included. Following a non-causative QF-PCR result, WES-CNV analysis was initially requested for 74.3% of the chorionic villus (CV) samples and 45% of the amniotic fluid (AF) samples. In case WES-CNV analysis did not reveal a causative aberration, SNV-re-analysis was requested in 41.7% of the CV samples and 17.5% of the AF samples. All initial analyses could be finished within 2 weeks after sampling. For SNV-re-analysis during pregnancy, turn-around-times (TATs) varied between one and 8 days.

Conclusion

We show a highly efficient all-in-one WES-based strategy, with short TATs, and the option of rapid SNV-re-analysis after a normal CNV result.  相似文献   
24.
The production of accurate and reliable data on copper ecotoxicology of marine algae depends on the use of trace metal clean techniques during experimentation. We reviewed the methodologies used in the literature on copper ecotoxicology of marine macro- and microalgae, specifically the use of trace metal clean procedures such as the labware used (glassware vs. plasticware), methods of cleaning the labware (acid soaking and ultrapure water rinsing), stock solution preparation (copper source and acidification), and measurement and reporting of dissolved copper concentrations. In terms of taxonomic classification, the most studied algal groups were the Phyla Ochrophyta, Bacillariophyta, Rhodophyta, and Chlorophyta. In terms of methodology, ~50% of the articles did not specify the labware, ~25% used glassware, and ~25% plasticware; ~30% of the studies specified cleaning protocols for labware to remove trace metal impurities; the copper form used to prepare the stock solutions was specified in ~80% of studies but acidification to stabilise the dissolved copper was performed in only ~20%; and the dissolved copper concentration was measured in only ~40% of studies. We discuss the importance of following trace metal clean techniques for the comparison and interpretation of data obtained on copper ecotoxicology in algae.  相似文献   
25.
In the climate adaptation literature, leadership tends to be an understudied factor, although it may be crucial for regional adaptation governance. This article shows how leadership can be usefully conceptualized and operationalized within regional governance networks dealing with climate adaptation. It applies an integrative framework inspired by complexity leadership theory, distinguishing several leadership functions to enhance the adaptive capacity of regional networks. We focus on one specific institutional innovation, appointed climate adaptation officers, who seek to connect science and governance practice, and to mainstream climate adaptation. Our question is twofold: What is the potential of climate adaptation officers to advance the adaptation agenda and to what extent did their establishment and working practice mirror the various leadership functions needed to raise the adaptive capacity of the regional network they operated in? The integrative leadership framework structures the analysis of climate adaptation officers forming part of a government-funded project seeking to enhance adaptation to climate variability in the central German region of Northern Hesse. The data consist of interviews with scientists and regional authority employees and project documentation including an evaluation. We find that climate adaptation officers raised awareness for climate adaptation and helped to shape and implement a number of projects within the overall KLIMZUG programme, highlighting impeding and enabling factors. The process of setting up this institutional innovation involved all forms of leadership functions and is an example of vertical mainstreaming. Its operation involved most clearly enabling and connective leadership functions and is an example of horizontal mainstreaming.  相似文献   
26.
Considering the important role that surface waters serve for drinking water production, it is important to know if these resources are under the impact of contaminants. Apart from environmental pollutants such as pesticides, compounds such as (xeno)estrogens have received al lot of research attention and several large monitoring campaigns have been carried out to assess estrogenic contamination in the aquatic environment. The introduction of novel in vitro bioassays enables researchers to study if – and to what extent – water bodies are under the impact of less-studied (synthetic) hormone active compounds. The aim of the present study was to carry out an assessment on the presence and extent of glucocorticogenic activity in Dutch surface waters that serve as sources for drinking water production. The results show glucocorticogenic activity in the range of <LOD – 2.4 ng dexamethasone equivalents L−1 (dex EQs) in four out of eight surface waters. An exploratory time-series study to obtain a more complete picture of the yearly average of fluctuating glucocorticogenic activities at two sample locations demonstrated glucocorticogenic activities ranging between <LOD – 2.7 ng dex EQs L−1. Although immediate human health effects are unlikely, the environmental presence of glucocorticogenic compounds in the ng L−1 range compels further environmental research and assessment.  相似文献   
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Seven fringing reef complexes were chosen along the leeward coast (west) of Barbados to study the effects of eutrophication processes upon the scleractinian coral assemblages. The structure of scleractinian coral communities was studied along an eutrophication gradient with a quantitative sampling method (line transect) in terms of species composition, zonation and diversity patterns. On the basis of these data the fringing reefs were divided into three ecological zones: back reef, reef flat, and spur and groove. Statistically discernible and biologically significant differences in scleractinian coral community structure, benthic algal cover and Diadema antillarum Philippi densities were recorded among the seven fringing reefs. High correlations between environmental variables and biotic patterns indicate that the effects of eutrophication processes (nutrient enrichment, sedimentation, turbidity, toxicity and bacterial activity) were directly and/or indirectly affecting the community structure of scleractinian coral assemblages. In general, species diversity was most sensitive in delineating among-reef, and among-zone, differences, which were attributed to intensification of eutrophication processes. Porites astreoides Lamarck, P. porites (Pallas), Siderastrea radians (Pallas), and Agaricia agaricites (Linnaeus) were the most abundant coral species in the polluted southern reefs. The absence and/or low abundance of coral species previously characterized as well adapted to high turbidity and sedimentation [i.e. Montastrea cavernosa Linnaeus, Meandrina meandrites (Linnaeus)] indicate that eutrophication processes may adversely affect these species. It is suggested that sediment rejection abilities, combined with feeding and reproductive strategies, are the primary biological processes of scleractinian corals through which eutrophication processes directly and/or indirectly affect the structure of coral communities.  相似文献   
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F. Sander 《Marine Biology》1981,64(2):199-205
Nutrient enrichment of inshore waters is considered the ultimate cause of the island mass effect of Barbados, and other tropicalislands. The present study is an evaluation of the three principal causative mechanisms of enrichment of Barbados coastal waters, i.e. run-off from land, a nutrient exchange between the benthos and overlying waters and internal waves of lunar periodicity. Attempts to link high precipitation to high primary production rates or low salinity with high nutrient levels were unsuccessful. This suggested that land-drainage was not an important factor. Comparisons of nutrient concentrations and C14 fixation rates in waters overlying two contrasting (sand and coral) benthic situations showed trends rather than statistically valid differences in these production variables. A simple calculation of potential nutrient supply versus actual demand showed that internal waves represent a potential source of enrichment. It is suggested that internal waves contribute to the observed high levels of standing crop and production which are characteristic of an island mass effect.  相似文献   
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