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141.
Seagrasses are threatened by multiple anthropogenic stressors, such as accumulating drift algae and increasing temperatures (associated with eutrophication and global warming, respectively). However, few seagrass experiments have examined whether exposure to multiple stressors causes antagonistic, additive, or synergistic effects, and this has limited our ability to predict the future health status of seagrass beds. We conducted a laboratory experiment to test whether abundance of Gracilaria comosa (3 levels; 0, 1.2, and 3.4 kg WW m−2), an algae that is resistant to wide environmental fluctuations (e.g. light, temperature, salinity, and oxygen levels), has negative effects on the small ephemeral seagrass, Halophila ovalis and whether the effects are exacerbated by high temperature (3 levels; 20, 25, and 30°C). We found an additive negative effect of the two stressors when tested simultaneously on 14 seagrass performance measures, with most data variability explained by the drift algae. For the individual plant performance measures (above- and below-ground growth and mortality, leaf area, internode distance, and root length and root volume), we found 5 additive effects, 4 synergistic effects, and 5 effects that were significant only for drift algae. We also documented a significant additive effect of drift algae and temperature on dissolved porewater sulphide (DS). A follow-up correlation analysis between DS and the 14 plant performance measures revealed significant or near-significant linear correlations on 9 of these responses (above- and below-ground growth, leaf area and weight, leaf mortality, and internode distance). In summary, we showed (a) that a stress-resistant drift algae can have strong negative effects on a small ephemeral seagrass, (b) this negative effect can increase both additively and synergistically with increasing temperature depending on performance measure, and (c) the negative effects may be mediated by a build-up of porewater DS. An implication of our findings is that resource managers aiming to preserve healthy seagrass beds in an almost certain future warmer world should increase efforts to keep drift algae populations low.  相似文献   
142.
Many countries in sub‐Saharan Africa have adopted similar approaches to tackle the challenges of rural water supply, including community‐based management, community participation and the demand‐responsive approach. These are often combined with nationwide programmes of capacity‐building and decentralization. This paper first shows how Uganda has adopted these approaches in its rural water supply programme. Based on Government documents, we construct an organizational framework that illustrates the overall programme and outlines the roles and responsibilities which actors are expected to fulfil. Second, based on interviews with sector staff and a review of Government documents, the paper examines challenges to successfully “walk the talk”; that is, it provides insight into challenges affecting programme implementation. Among numerous difficulties, two key issues are highlighted: local political interference and the weak capacity of local governments. Concerning local political interference, local planning processes need to be reformed so that local politicians commit more strongly to improving water supply. Regarding local government capacity, the Government department responsible for the programme has established eight regional units that provide support to local governments. This promising strategy, combined with more appropriate engagement and the commitment of local politicians, should help to improve the implementation of the rural water supply programme in Uganda.  相似文献   
143.

Objectives

To define the prognostic markers of fetal dilated bowel loops.

Methods

National non-interventional study of 133 consecutive prenatal observations of dilated loops including ultrasound examinations, complementary laboratory tests, magnetic resonance imaging (MRI), outcomes, and postnatal diagnosis.

Results

One hundred twenty seven cases were classified according to outcome: Group 1, very severe (n = 43), Group 2, children needing specific care (n = 39), and Group 3, healthy children (n = 45). Prenatal ultrasound scan suggested duodenal obstruction in 30 cases, small bowel obstruction in 81, colonic obstruction in 11, and diffuse dilatation in 5. Diameter of dilated loops did not significantly differ between the groups. A poor prognosis was significantly associated with duodenal obstruction, genetic anomalies (53% vs. 21.8%), including aneuploidies or CFTR gene mutations and abnormal amniotic fluid biochemistry (86.4% vs. 38.7%). A good prognosis was associated with regression of dilatation and normal MRI.

Conclusion

In this study, postnatal outcomes for fetuses with intestinal dilatation were best predicted by assessing the level of obstruction with prenatal ultrasound and MRI, determining the presence of associated malformations, amniotic fluid biochemical and genetic testing, and monitoring for regression of bowel dilatation. These results should help inform future guidelines on the prenatal and neonatal management of congenital intestinal obstruction.  相似文献   
144.
Conservation technology holds the potential to vastly increase conservationists’ ability to understand and address critical environmental challenges, but systemic constraints appear to hamper its development and adoption. Understanding of these constraints and opportunities for advancement remains limited. We conducted a global online survey of 248 conservation technology users and developers to identify perceptions of existing tools’ current performance and potential impact, user and developer constraints, and key opportunities for growth. We also conducted focus groups with 45 leading experts to triangulate findings. The technologies with the highest perceived potential were machine learning and computer vision, eDNA and genomics, and networked sensors. A total of 95%, 94%, and 92% respondents, respectively, rated them as very helpful or game changers. The most pressing challenges affecting the field as a whole were competition for limited funding, duplication of efforts, and inadequate capacity building. A total of 76%, 67%, and 55% respondents, respectively, identified these as primary concerns. The key opportunities for growth identified in focus groups were increasing collaboration and information sharing, improving the interoperability of tools, and enhancing capacity for data analyses at scale. Some constraints appeared to disproportionately affect marginalized groups. Respondents in countries with developing economies were more likely to report being constrained by upfront costs, maintenance costs, and development funding (p = 0.048, odds ratio [OR] = 2.78; p = 0.005, OR = 4.23; p = 0.024, OR = 4.26), and female respondents were more likely to report being constrained by development funding and perceived technical skills (p = 0.027, OR = 3.98; p = 0.048, OR = 2.33). To our knowledge, this is the first attempt to formally capture the perspectives and needs of the global conservation technology community, providing foundational data that can serve as a benchmark to measure progress. We see tremendous potential for this community to further the vision they define, in which collaboration trumps competition; solutions are open, accessible, and interoperable; and user-friendly processing tools empower the rapid translation of data into conservation action. Article impact statement: Addressing financing, coordination, and capacity-building constraints is critical to the development and adoption of conservation technology.  相似文献   
145.
1999年,在毛里塔尼亚和塞内加尔的塞内加尔三角洲下部,槐叶苹(Salvinia moesta)的侵入对当地居民的社会经济状况以及湿地生物多样性构成严重的威胁.分别于2000年5月在塞内加尔和毛里塔尼亚及2001年4月在塞内加尔的河面引进槐叶苹象甲(Cyteobagous salviniae),最终实现了对槐叶苹的有效生物控制.2001年10月,象甲起到的作用已非常明显.植物的颜色由绿色变为深褐色或黑色,槐叶苹最终沉入水底.2001年11~12月对槐叶苹象甲扩散的监控证实了生物控制结果的真实性.至2002年4月已有结论,塞内加尔河畔槐叶苹不再成为问题.  相似文献   
146.
The European Landscape Convention indicates that assessment of different dimensions that exist in landscapes should be taken into account in planning. In this study, we first investigated ecological, cultural and social values as perceived by the local people in a highway-planning process in Sweden. Next, we explored which factors influenced the local people's participation in the road-planning process. We used questionnaires, planning documents and the Theory of Planned Behavior to investigate the relations between different factors and local people's participation in the planning process. The results showed that people presumed the ecological values in the landscape to be adversely affected by the new road, while the social values would remain the same. Landowners had heard of the participatory-process, but few participated. Those who lived within 300 m of the road were more active in the planning process than people living further away. The findings suggest that people living within a few hundred metres of the road should be treated as key stakeholders in the planning process. The involvement of other stakeholders, and when in the public participation process stakeholders should be involved, is also discussed.  相似文献   
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The starting point of the study is six research subjects in which ergonomic work analysis is conceived as a ‘tool’ used to develop professional types of training programmes concerning present or future work activities. All these approaches reveal a tendency for instructors to give priority to the experience of the trainee and interventions designed on the basis of concrete work situations. The question is to know if this is the affirmation of the values of an alternative socio-political project or simply that of a cyclical interest corresponding to increasing concerns regarding the management of labor which accompanied the process of the technical transformation and the shrinkage of the job market.  相似文献   
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