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381.
Fragmentation of the boreal forest by linear features, including seismic lines, has destabilized predator–prey dynamics, resulting in the decline of woodland caribou (Rangifer tarandus caribou) populations. Restoration of human-altered habitat has therefore been identified as a critical management tool for achieving self-sustaining woodland caribou populations. However, only recently has testing of the response of caribou and other wildlife to restoration activities been conducted. Early work has centered around assessing changes in wildlife use of restored seismic lines. We evaluated whether restoration reduces the movement rates of predators and their associated prey, which is expected to decrease predator hunting efficiency and ultimately reduce caribou mortality. We developed a new method for using cameras to measure fine-scale movement by measuring speed as animals traveled between cameras in an array. We used our method to quantify speed of caribou, moose (Alces alces), bears (Ursus americanus), and wolves (Canis lupus) on treated (restored) and untreated seismic lines. Restoration treatments reduced travel speeds along seismic lines of wolves by 1.38 km/h, bears by 0.55 km/h, and caribou by 1.57 km/h, but did not reduce moose travel speeds. Reduced predator and caribou speeds on treated seismic lines are predicted to decrease encounter rates between predators and caribou and thus lower caribou kill rates. However, further work is needed to determine whether reduced movement rates result in reduced encounter rates with prey, and ultimately reduced caribou mortality.  相似文献   
382.
Global warming and greenhouse gas emissions pose severe threats to environmental sustainability. A sustainable environment is a prerequisite for long-term socioeconomic growth and human survival. Green technology is brought about by a country's economic and financial openness, and education provides knowledge to the public and labor, contributing to environmental sustainability. Thus, this research aims to unveil the liaison between human capital, trade openness, and environmental quality for Russia, Brazil, India, China, and South Africa (BRICS) countries from 1998 to 2018. Several econometric methods, including the Driscoll–Kraay standard errors and the Dumitrescu–Hurlin causality approaches, reveal long-run and causal relationships among the modelled indicators. The Driscoll–Kraay standard error results show that human capital is negatively related to carbon dioxide emissions (CO2 emissions). Imposing high tariffs and excise duties, changing tax structures, discouraging the inflow of polluted commodities, and encouraging green trade can help BRICS combat high environmental pollution. The results show that a one-point increase in human capital in models 1 and 2 can reduce CO2 emissions by 1.5279 and 0.1538 points, respectively. In contrast, a 1% growth in trade can lead to a rise in CO2 emissions of 0.3731% and 0.2384%, respectively. Similarly, financial development and energy consumption result in high CO2 emissions in the long run. Moreover, a feedback effect of the human capital index on CO2 emissions is discovered. As a result of the findings, the government and responsible authorities should provide financial support and encourage investments in the region's energy-resourceful and sustainable green projects.  相似文献   
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Development of waste heat-driven absorption-based cooling system is inspired for the need of removing high heat flux from the sustainable data centre environment. This paper presents a simulation study of single-stage Lithium Bromide–Water (LiBr–H2O) vapour absorption heat pump for chip cooling. In the present work, a complete thermodynamic analysis of the single-stage LiBr–H2O vapour absorption-based heat pump for chip cooling without a solution heat exchanger is performed and a user friendly graphical user interface (GUI) package including visual components is developed by using MATlab (2008b). The effect of chip heat flux on COP (Coefficient of Performance), flow rates and conductance is examined using the developed package. The model is verified using the data available in the literature which indicates that there is a greater reduction in the absorber load. The influence of chip heat flux on the performance and thermal loads of individual components are studied, and it is concluded that COP decreases from 0.7121 to 0.68924 with increase in chip heat flux.  相似文献   
384.
Beckwith–Wiedemann syndrome (BWS) is an overgrowth syndrome associated with congenital malformations and tumour predisposition. BWS results from variable mutations or epigenetic modifications of imprinted genes in the 11p15 chromosomal region. We present a fetus with mild general overgrowth and bilateral enlarged echogenic kidneys with loss of the corticomedullary differentiation in which prenatal diagnosis of BWS was suspected. The rest of the fetal anatomy and the amniotic fluid volume appeared normal. After termination of the pregnancy, molecular analysis confirmed the diagnosis of BWS by showing an isolated hypermethylation of the H19 gene. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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Crigler–Najjar syndrome type I (CN-I) is a rare and severe inherited disorder of bilirubin metabolism, caused by the total deficiency of bilirubin-UDP-glucuronosyltransferase (UGT) activity. Enzymatic diagnosis cannot be performed in chorionic villi or amniocytes as UGT is not active in these tissues. The cloning of the UGT1 gene and the identification of disease-causing mutations have led to the possibility of performing DNA-based diagnosis. Here we report DNA-based prenatal diagnosis of CN-I in two Tunisian families in whom CN-I patients were diagnosed. As we had previously shown that CN-I was, in Tunisia, associated with homozygosity for the Q357R mutation within the UGT1 gene, we were able to detect this mutation in both families and to show that it was easily recognized by single-strand conformation polymorphism (SSCP) analysis. In both cases, SSCP analysis of fetal DNA showed that the fetus was heterozygous for the Q357R mutation. In one family, the pregnancy was carried to term and a healthy baby was born, whereas, in the other family, the pregnancy is still continuing. Thus the prenatal diagnosis of CN-I is possible, provided disease-causing mutations have been identified. SSCP analysis of DNA prepared either from amniocytes or from chorionic villi is a simple, reliable and fast method for prenatal diagnosis. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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During the last 30 years, growing demand for science-based policy making has contributed to the mobilization of scientific cooperation alongside transnational political arrangements for addressing environmental issues. Following the contemporary trend toward regionalizing environmental policy and practice, many of these scientific joint efforts have focused on a regional scale. This article examines regional scientific cooperation in the context of the institutionalization of mountain regions in Europe. Such cooperation can be observed from the Pyrenees to Central Asia, albeit with a degree of variation that largely remains unexplored in scientific research. Sometimes scientific cooperation served to lay the groundwork of a mountain policy initiative, other times it appeared in its wake; some examples appear as loose networks of individual scientists, others are set up as formalized monitoring and observation centers; finally, some scientific joint efforts are formally linked to, or incorporated in a mountain policy initiative, while others are largely independent. The article proposes a new typology for understanding the interactions between regional scientific mobilization and regional policy making and provides up-to-date portraits of six main cases.  相似文献   
390.
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