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161.
In this study the ecological importance of common ragweed (Ambrosia artemisiifolia L.; Asteraceae) was investigated in in vitro bioassays as it is one of the most widespread annual weeds occurring on arable land in Hungary. Eight fractions were derived from ragweed inflorescence water extract by low vacuum column chromatography and their biological activity was investigated by Amaranthus hypochondriacus L. cv. Edit (Amaranthaceae) germination bioassay. As a result of the germination bioassay the chromatographic method was modified to harvest the most effective fractions in only one fraction, which was used in three concentration (10, 50, 100 mg x kg(-1)) for algal growth inhibition bioassay.Results showed significant growth inhibition in case of both applied algal species.  相似文献   
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Federal and many state agencies are required to perform environmental justice analyses of their policies prior to implementing them to prevent undue impacts on low income and minority populations. However, little academic attention has been paid to the quality of these ex-ante environmental justice analyses. This investigation evaluates the methods used to perform environmental justice analyses during siting and permitting processes. The study uses both the California Energy Commission guidelines for environmental justice analyses and a method that geographically maps air pollution to perform ex-ante environmental justice analyses of three power plants. The objective is to see if results from using these two analysis methods differ substantially. Findings indicate that the mapping technique employed represents a substantial improvement over defining the impacted population using proximity methods because it accounts for the geographical distribution of the hazard. Furthermore, using multiple comparison benchmarks to determine whether the impacted population constitutes an environmental justice population improves upon existing methods by accounting for the spatial distribution of minority and low income populations and for the possibility that there is a relatively high or relatively low percentage of low income and minority persons in both the impacted and comparison regions.  相似文献   
164.
Increasing losses from weather related extreme events coupled with limited coping capacity suggest a need for strong adaptation commitments, of which public sector responses to adjustments to actual and expected climate stimuli are key. The European Commission has started to address this need in the emerging European Union (EU) climate adaptation strategy; yet, a specific rationale for adaptation interventions has not clearly been identified, and the economic case for adaptation to extremes remains vague. Basing the diagnosis on economic welfare theory and an empirical analysis of the current EU and member states’ roles in managing disaster risk, we discuss how and where the public sector may intervene for managing climate variability and change. We restrict our analysis to financial disaster management, a domain of adaptation intervention, which is of key concern for the EU adaptation strategy. We analyse three areas of public sector interventions, supporting national insurance systems, providing compensation to the affected post event as well as intergovernmental loss sharing through the EU solidarity fund, according to the three government functions of allocation, distribution, and stabilization suggested by welfare theory, and suggest room for improvement.  相似文献   
165.
Toxicity was observed in whole effluent toxicity (WET) studies with the freshwater alga, Pseudokirchneriella subcapitata, in three consecutive monthly studies, (NOEC = 50-75%). Toxicity was not observed to Ceriodaphnia dubia or the fathead minnow, Pimephales promelas in concurrent studies. Selected toxicity identification evaluation (TIE) tests were conducted in a tiered approach to eliminate possible toxicants and progressively identify the causative agent. Filtration following alkaline adjustment (pH 10 or 11) was effective in eliminating significant growth effects and also reduced phosphate concentration. The TIE studies confirmed that the observed effluent toxicity was caused by excess ortho-phosphate in the effluent not by overstimulation or related to unfavorable N:P ratios; but due to direct toxicity. The 96-h 25% inhibition concentration (IC25) of ortho-phosphate to P. subcapitata was 3.4 mg L−1 while the maximum acceptable toxicant concentration was 4.8 mg L−1. This study illustrates the value of multi-species testing and also provides an example of an effective TIE using algae identifying an unanticipated toxicant.  相似文献   
166.

Objective

To evaluate fetal brain development using MRI (magnetic resonance imaging) in CDH (congenital diaphragmatic hernia).

Methods

52 isolated left CDH and 104 control fetuses were imaged using MRI. Brain morphometry (Biparietal diameter—BPD, brain fronto-occipital diameter—BFOD, third ventricle, posterior ventricles, transcerebellar diameter—TCD, anteroposterior and craniocaudal cerebellar vermis diameter—AP and CC) and cortical structures (bilateral cingulate fissure—CF, insular fissure—IF, insular depth - ID) were compared with controls using Mann–Whitney test.

Results

Median gestational age at MRI (p = 0.95)and the median biparietal diameter (p = 0.737) were comparable. Among morphometric parameters, only the brain fronto-occipital diameter was significantly smaller in CDH (p = 0.001) and the third ventricle was significantly greater in CDH (<0.0001). Among cortical structures, the cingulate and insular fissures were significantly deeper in CDH fetuses (p < 0.0001) as the insular depth ID was smaller in CDH (p < 0.03).

Conclusions

CDH fetuses have a smaller fronto-occipital diameter, reduced insular depth, deeper cingulate and insular fissure, and greater third ventricle width as compared to controls. These findings suggest that left CDH may have an impact on fetal brain development with an overall reduction in brain volume.  相似文献   
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168.

Agriculture is the main occupation of the majority of people in India. The majority of the population in India is dependent (directly or indirectly) on agriculture as an occupation. The agriculture sector requires more freshwater and power for better yield in the current scenario. Nevertheless, the ever-increasing rate of energy consumption, limited fossil fuels, and rising pollution have made the expansion of renewable resources essential. Due to the suitable solar potential available in India, the deployment of solar energy has been more as compared to other renewable resources. The current study aims to discuss the various technologies, initiatives and policies of solar energy usage in agriculture. This work delivers an assessment of the advancement of solar energy vis-à-vis agricultural applications through the greenhouse concept and photovoltaic approach in India. Various agricultural applications of solar energy, such as solar water desalination system, solar water pumping system, solar crop dryer system for food safety, etc. are discussed as a means to promote solar-based technology. It also highlights the scenario of solar energy in India with important accomplishments, developmental approaches, and future potential. In-depth studies of various policies and government initiatives including those in research and development are also discussed. The current survey on solar technologies will be an aid to agribusiness frameworks to comprehend the statuses, obstructions, and extent of advancement. Finally, some future recommendations for further developments in this approach are discussed. This work sheds light on varied areas of solar energy-assisted agricultural systems as a potentially sustainable and eco-friendly pathway.

Graphical abstract
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