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There are over 50 SARS-CoV-2 candidate vaccines undergoing Phase II and III clinical trials. Several vaccines have been approved by regulatory authorities and rolled out for use in different countries. Due to concerns of potential teratogenicity or adverse effect on maternal physiology, pregnancy has been a specific exclusion criterion for most vaccine trials with only two trials not excluding pregnant women. Thus, other than limited animal studies, gradually emerging development and reproductive toxicity data, and observational data from vaccine registries, there is a paucity of reliable information to guide recommendations for the safe vaccination of pregnant women. Pregnancy is a risk factor for severe COVID-19, especially in women with comorbidities, resulting in increased rates of preterm birth and maternal morbidity. We discuss the major SARS-CoV-2 vaccines, their mechanisms of action, efficacy, safety profile and possible benefits to the maternal-fetal dyad to create a rational approach towards maternal vaccination while anticipating and mitigating vaccine-related complications. Pregnant women with high exposure risks or co-morbidities predisposing to severe COVID-19 infection should be prioritised for vaccination. Those with risk factors for adverse effects should be counselled accordingly. It is essential to support patient autonomy by shared decision-making involving a risk-benefit discussion with the pregnant woman.  相似文献   
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This research presents an overview of where the gaps in the literature exist in relation to the link between environmental regulation and proactive environmental management and competitiveness, and incorporates them in a whole model. Different papers have highlighted only partial aspects of these relationships. Specifically, this research evaluates the relationship between managerial perception and the different styles of environmental regulations – command-and-control versus voluntary norms – the mediator role of environmental management in the link between environmental regulations and competitiveness, the effect of competitiveness on financial performance, and the two-way relationship between proactive environmental management and financial performance. Finally, this paper uses statistical evidence to test and estimate causal relationships through a structural equation modelling of 208 firms affected by IPPC law in Spain. There is a lack of systematic statistical evidence on this topic in the literature, which mainly focuses on case studies. The results show that when environmental regulation stems from command-and-control legislation its influence on managerial perception and proactive environmental management is not significant. However, when environmental regulation stems from voluntary norms, its effects are positive. Moreover, investment in proactive environmental management contributes to increasing the competitiveness of the firm. Cost and differentiation competitive advantage have a positive impact on financial performance. Finally, the link between proactive environmental management and financial performance may follow different paths: (1) neither direct nor single, because it can depend on competitive advantage, and (2) direct, because there is a significant two-way relationship between these variables (proactive environmental management influences financial performance and financial performance influences proactive environmental management).  相似文献   
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Off Patagonian coasts, Argentina, the dusky dolphin is one of the most common small cetaceans. This species is the aim of newly developed watching activities during summer in Golfo Nuevo. However, the real occurrence and movement pattern are unknown. The objectives of this work were to investigate the predictability of dusky dolphin distribution, group structure and behaviour in the western portion of Golfo Nuevo, with respect to environmental features (bottom depth, bottom slope, distance from shore and substrate). Random transects in the bay were searched by small boat during the summer and autumn of 2001–2004. When a group of dolphins was sighted, estimates of group size, composition (mothers with calves, adults and juveniles only, and mixed groups) and the predominant activity (feeding, travelling, socialising, resting and milling) were recorded and thereafter at 2 min intervals. A grid of 1.5 × 1.5 km was constructed and each cell was characterised by environmental features, Area Use Index (percent of total annual search effort) and Activity Index (predominant behaviour of groups observed in that cell). Mothers with calves and smaller groups and resting behaviour occurred in shallowest waters supporting the idea/hypothesis that movement to shallower water is related to increased safety for individuals. Travelling occurred in the deepest areas with other behaviours observed in intermediate depths. Dolphin distribution within the bay differed significantly between years, but this was not related to any of the factors analysed in this study. Although there was considerable variation between years, in general, dolphins were found in deeper waters further from shore (except for mother–calf groups) and over areas with steeper seafloor gradient. The high variability in the distribution of the animals does not allow for the generation of a simple, area-specific management plan.  相似文献   
97.
Pesticide volatilization to the atmosphere may be a major pathway of dissipation closely linked with environmental, physico-chemical and technical factors. Understanding the volatilization process requires systems that make it possible to control some of these factors. Wind tunnels meet to these criteria. The volatilization flux is determined from a mass balance, using the difference in atmospheric pesticide concentration between the entrance and the exit of the tunnel and the airflow rate. An experiment was carried out in June 2000 to study the repeatability of this technique. Volatilization of trifluralin was measured in three wind tunnels for 8 days with a sampling period varying between 3 h and 2 days. Pesticide concentration was determined by trapping by XAD-2 resin in a two-stage cartridge, solvent extraction and analysis by gas chromatography. Cumulated losses through volatilization reached 30% of the measured application dose after 8 days, with a variability of less than 20% between the three tunnels. Approximately 20% remained in the topsoil (0–2 cm), with a variability of 14% between the three tunnels. The decrease in the volatilization flux over time is coherent with the expected theoretical evolution for a volatile pesticide such as trifluralin and with previous experimental works.  相似文献   
98.
This paper estimates the true economic income for the Chilean mining sector, using the welfare foundations for the usual net domestic product (NDP) income measure of the traditional National Accounts System (NAS) provided by [Weitzman, M., 1976. On the welfare significance of national product in a dynamic economy. Quarterly Journal of Economics. 90, 156–162; Weitzman, M., 2000. The linearised Hamiltonian as comprehensible NDP. Environment and Development Economics. 5, 55–68]. The total depletion of natural capital caused by mining is calculated by estimating, on the one hand, the depreciation of resources (using the net price approach) and, on the other, the environmental costs provoked by mining activity. The results show that, correcting the usual GDP measure for man-made capital depreciation plus the total loss of natural capital, the standard mining GDP measure of the NAS overestimates by 31–36% the economic income generated by Chile's mining sector during the period 1985–1996.  相似文献   
99.
Establishing politically feasible water markets: a multi-criteria approach   总被引:3,自引:0,他引:3  
A multiple criteria decision-making (MCDM) model to simulate the establishment of water markets is developed. The environment is an irrigated area governed by a non-profit agency, which is responsible for water production, allocation, and pricing. There is a traditional situation of historical rights, average-cost pricing for water allocation, large quantities of water used, and inefficiency. A market-oriented policy could be implemented by accounting for ecological and political objectives such as saving groundwater and safeguarding historical rights while promoting economic efficiency. In this paper, a problem is solved by compromise programming, a multi-criteria technique based on the principles of Simonian logic. The model is theoretically developed and applied to the Lorca region in Spain near the Mediterranean Sea.  相似文献   
100.
The potential of removing nickel and copper from industrial electroplating wastewaters by using mesoporous materials with MCM-41 type structure functionalised with different ratios of aminopropyl groups, namely Na50, Na25 and Na5, were evaluated. The synthesised solids sorbents obtained were characterised by X-ray diffraction, elemental chemical analysis and IR spectroscopy. In preliminary experiments, studies were carried out to determine the optimal experimental conditions for the retention of heavy ions. Effects of concentration, optimal pH, interference with humic substances and other metals were studied for Na5, which showed the best capacity of absorption determined by the corresponding isotherm. This material has a greater selectivity against sodium, indicating that ionic strength does not affect the extraction. Results of an application of this material to remove nickel and copper in synthetic and real industrial wastewater samples from an electrochemical industry area are shown with successful results. The lowest level of nickel and copper were observed when Na5 was used. This observation suggests that reactive aminopropyl-Si MCM-41 and similar materials may be a promising and provide for alternative environmental technologies in the future.  相似文献   
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