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31.
Claudia Kuenzer Ian Campbell Marthe Roch Patrick Leinenkugel Vo Quoc Tuan Stefan Dech 《Sustainability Science》2013,8(4):565-584
Hydropower developments along the main stem of the Mekong River and its tributaries cause transboundary effects within the Mekong Basin Region, which comprises parts of six countries. On the one hand, the provision of hydropower triggers economic development and helps to meet the rising energy demand of the Mekong riparian countries, especially China, Thailand, and Vietnam. On the other hand, the negative impact of dam construction, mainly altered water flow and sediment load, has severe impacts on the environment and the livelihoods of the rural Mekong population. Several discrepancies exist in the needs, demands, and challenges of upstream versus downstream countries. Against the common apprehension that downstream countries are powerlessly exposed to mainly negative impacts whereas upstream countries unilaterally benefit from hydropower, the authors argue that upstream–downstream relations are not really clear-cut. This conclusion is based on a consideration of the complex power play between Mekong riparians, with a focus on recent power trade interactions. The article investigates the consequences of hydropower dams for the Mekong region as well as the role of supranational players, such as the Mekong River Commission and the Greater Mekong Subregion Initiative, on the hydropower debate. It is not nations that are the winners or losers in the hydropower schemes in the Mekong, but rather parts of the riparian population: a few influential and powerful elites versus the large mass of rural poor. 相似文献
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Lieke J. van Heurn Audrey Coumans Monique C. Haak Annemarth van der Kaaij L. W. Ernest van Heurn Eva Pajkrt Joep P. M. Derikx 《黑龙江环境通报》2023,43(12):1495-1505
Several factors associated with poor outcome in patients with prenatally diagnosed sacrococcygeal teratoma (SCT) have been found. However, the prognostic accuracy of these factors has not been well established. Therefore, we aimed to systematically review the prognostic accuracy of factors associated with poor outcome in these patients. We queried Search Premier, COCHRANE Library, EMCARE, EMBASE, PubMed, ScienceDirect, and Web of Science databases to identify studies regarding patients with prenatally diagnosed SCT. Poor outcome was defined as termination of pregnancy (TOP), intrauterine fetal death (IUFD), or perinatal death. We estimated the odds ratio of factors associated with poor outcome. Eleven studies (447 patients) were included. Overall mortality, including TOP, was 34.9%. Factors associated with poor outcome in fetuses with prenatally diagnosed SCT were cardiomegaly, hypervascular tumor, solid tumor morphology, fetal hydrops, and placentomegaly. A tumor volume to fetal weight ratio (TFR) of >0.12 before a gestational age of 24 weeks is predictive of poor outcome. The prognostic accuracy of factors associated with poor outcome in fetuses prenatally diagnosed with SCT seems promising. Factors associated with cardiac failure such as cardiomegaly, hypervascular tumor, solid tumor morphology, fetal hydrops, placentomegaly, and TFR >0.12 were found to be predictive of poor outcome. 相似文献
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Manon Gijtenbeek Monique C. Haak Tom J. P. Huberts Johanna M. Middeldorp Frans J. C. M. Klumper Femke Slaghekke Enrico Lopriore Dick Oepkes Jeanine M. M. van Klink 《黑龙江环境通报》2020,40(7):825-830
Objective
To investigate whether perioperative fetal hemodynamic changes in twin-to-twin transfusion syndrome (TTTS) are associated with neurodevelopmental impairment (NDI) at two years.Methods
Doppler parameters of three sonograms (day before, first day after and 1 week after laser surgery for TTTS) were assessed for correlation with neurodevelopmental outcome at two years (2008-2016). NDI was defined as: cerebral palsy, deafness, blindness, and/or a Bayley-III cognitive/motor developmental test-score > 2SD below the mean.Results
Long-term outcome was assessed in 492 TTTS survivors. NDI was present in 5% (24/492). After adjustment for severe cerebral injury (present in 4%), associated with NDI were: middle cerebral artery peak systolic velocity (MCA-PSV) >1.5 multiples of the median (MoM) 1 day after surgery (odds ratio [OR] 4.96; 95% confidence interval [CI]: 1.17-21.05, P = .03), a change from normal umbilical artery pulsatility index (UA-PI) presurgery to UA-PI >p95 postsurgery (OR 4.19; 95% CI: 1.04-16.87, P = .04), a change from normal to MCA-PSV >1.5MoM (OR 4.75; 95% CI: 1.43-15.77, P = .01).Conclusion
Perioperative fetal hemodynamic changes in TTTS pregnancies treated with laser are associated with poor neurodevelopmental outcome. Prospective research on the cerebrovascular response to altered hemodynamic conditions is necessary to further understand the cerebral autoregulatory capacity of the fetus in relation to neurodevelopmental outcome. 相似文献39.
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Daniel Houle Christian Gagnon Suzanne Couture Alain Kemp 《Water, Air, & Soil Pollution: Focus》2004,4(2-3):247-261
Since 1985, monitoring activities have been conducted in a networkof 43 lakes comprising the Québec portion of the Long-Range Transport of Airborne Pollutants (LRTAP) program. The results to date indicate that Québec lakes generally are responding positively to the generalized decline in precipitation sulfate (SO4 2-), with 40 of the 43 lakes now showing steep declines in SO4 2- concentrations. The drop in SO4 2- was associated with a significant decrease in Ca2+ concentrations in 77% of the lakes (67% for Mg2+ concentrations). Overall, the acid-neutralizing capacity was increasing in 19 lakes and decreasing only in three, while 21 lakes showed no temporal trends. Compared with previous trend studies of the LRTAP-Québec network for the period of 1985–1993, the longer period (1985–1999) shows a clear improvement, with the proportion of lakes that were acidifying changing from 24 to 7% and with the proportion of lakes that were recovering changing from 16 to 35%. These observations suggest that the recent drop in SO4 2- deposition in the northeastern U.S. and eastern Canada was significant enough to allow chemical recovery for a significant proportion of Québec lakes. 相似文献