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21.
Using data from the National Longitudinal Survey of Adolescent to Adult Health, we estimate the effect of peers’ alcohol consumption and alcohol prices on the drinking habits of high-school-age youth. We use the two-stage residual inclusion method to account for the endogeneity of peer drinking in nonlinear models. For our sample of high school students, we find that peer effects are statistically and economically significant regarding the choice to participate in drinking but are not significant for the frequency of drinking, including binge drinking. Regarding alcohol prices, even though we have good price variation in our sample, alcohol prices are not found to be significant. The results are important for policymakers who are considering policies to reduce underage drinking, as we conclude that no significant impact on underage drinking will result from low-tax states’ increasing excise taxes on alcohol so they are similar to those of high-tax states. Policymakers may choose to focus instead on the influence of peers and changing the social norm behavior. 相似文献
22.
Parker Crutchfield 《Bioethics》2020,34(2):190-194
In a recent issue of Bioethics, I argued that compulsory moral bioenhancement should be administered covertly. Alexander Zambrano has criticized this argument on two fronts. First, contrary to my claim, Zambrano claims that the prevention of ultimate harm by covert moral bioenhancement fails to meet conditions for permissible liberty-restricting public health interventions. Second, contrary to my claim, Zambrano claims that covert moral bioenhancement undermines autonomy to a greater degree than does overt moral bioenhancement. In this paper, I rebut both of these arguments, then finish by noting important avenues of research that Zambrano’s arguments motivate. 相似文献
23.
Sensitive biological measures of river ecosystem quality are needed to assess, maintain or restore ecological conditions of water bodies. Since our understanding of these complex systems is imperfect, decision-making requires recognizing uncertainty. In this study, a new predictive multi-metric index based on fish functional traits was developed to assess French rivers. Information on fish assemblage structure, local environment and human-induced disturbances of 1654 French river sites was compiled. A Bayesian framework was used to predict theoretical metric values in absence of human pressure and to estimate the uncertainty associated with these predictions. The uncertainty associated with the index score gives the confidence associated with the evaluation of site ecological conditions.Among the 228 potential metrics tested, only 11 were retained for the index computation. The final index is independent from natural variability and sensitive to human-induced disturbances. In particular, it is affected by the accumulation of different degradations and specific degradations including hydrological perturbations. Predictive uncertainty is globally lower for IPR+ than for underlying metrics.This new methodology seems appropriate to develop bio-indication tools accounting for uncertainty related to reference condition definition and could be extended to other biological groups and areas. Our results support the use of multi-metric indexes to assess rivers and strengthen the idea that examination of uncertainty could contribute greatly to the improvement of the assessment power of bio-indicators. 相似文献
24.
The impact of hybrids between genetically modified crop plants and their related species: introgression and weediness 总被引:4,自引:0,他引:4
H. DARMENCY 《Molecular ecology》1994,3(1):37-40
Assessing the impact of hybrids between transgenic plants and nontarget wild species involves answering several questions such as: (i) what are the hybridization and introgression rates; (ii) what is the behaviour of a transgene in a wild population; and (iii) what will be the consequences of the expression of a transgene in a wild population? These issues are discussed using results from experiments on oilseed rape and wild related Brassiceae. Evidence is given of large variations in the estimates of cross-fertilization probabilities. The first stage of introgression into wild populations is demonstrated to occur spontaneously through back-crossing. Population analysis may also be valuable to detect traces of past introgression. Data from the literature on weed biology, and especially herbicide resistance, are used to illustrate the behaviour of a new gene in weed populations. The need for computer models simulating the introgression process is stressed. 相似文献
25.
Wei Liu Yaoting Sun Weigang Ge Fangfei Zhang Lin Gan Yi Zhu Tiannan Guo Kexin Liu 《Molecular & cellular proteomics : MCP》2022,21(2):100187
Drug resistance is a critical obstacle to effective treatment in patients with chronic myeloid leukemia. To understand the underlying resistance mechanisms in response to imatinib mesylate (IMA) and adriamycin (ADR), the parental K562 cells were treated with low doses of IMA or ADR for 2 months to generate derivative cells with mild, intermediate, and severe resistance to the drugs as defined by their increasing resistance index. PulseDIA-based (DIA [data-independent acquisition]) quantitative proteomics was then employed to reveal the proteome changes in these resistant cells. In total, 7082 proteins from 98,232 peptides were identified and quantified from the dataset using four DIA software tools including OpenSWATH, Spectronaut, DIA-NN, and EncyclopeDIA. Sirtuin signaling pathway was found to be significantly enriched in both ADR-resistant and IMA-resistant K562 cells. In particular, isocitrate dehydrogenase (NADP(+)) 2 was identified as a potential drug target correlated with the drug resistance phenotype, and its inhibition by the antagonist AGI-6780 reversed the acquired resistance in K562 cells to either ADR or IMA. Together, our study has implicated isocitrate dehydrogenase (NADP(+)) 2 as a potential target that can be therapeutically leveraged to alleviate the drug resistance in K562 cells when treated with IMA and ADR. 相似文献
26.
Zafar Iqbal Khan Kafeel Ahmad Muhammad Ashraf Rukhsana Parveen Zahara Bibi Irfan Mustafa 《人类与生态风险评估》2016,22(1):86-98
The present research was conducted in district Jhang, Pakistan, to evaluate the concentration of metals/metalloids in soil and pumpkin (Cucurbita maxima) irrigated with domestic wastewater. Data revealed that the levels of metals and metalloids in soil samples from two different sites were below the safe limits except Cd, whereas, in the vegetable, the concentrations of As, Se, Ni, Mo, Pb, Mn, and Cu were above the safe limits. The levels of 12 metals and metalloids in the soil were ranged between 0.14 to 22.76 mg/kg at site-I and 0.16 to 22.13 mg/kg at site-II. The levels of these metals in the vegetable were found 0.35 to 61.13 mg/kg at site-I and 0.31 to 53.63 mg/kg at site-II. The transfer factor at both sites was highest for As and Co. The pollution load index recorded for Se, Cu, Cd, Mo, Pb, and Co was greater than 1. The daily intake of As, Mn, and Mo was above the oral reference dose, which reflects that the intake of pumpkin is not safe for the inhabitants of the selected sites. The control measures should be taken to phytoextract heavy metals and metalloids from polluted sites so as to reduce the health risks. 相似文献
27.
In the past few decades, major advances in environmental protection within the coating application industry have been made. In spite of this technological progress, approximately 50% of industrial-solvent emissions still come from the paint-application sector. The advances made in reducing emissions for plants requiring licensing have unfortunately had no influence on the environmental efforts of smaller companies. Solvent-reduced painting systems, such as high-solid paints, water-based coating, and powder coating have not been able to achieve acceptance, nor have innovative application technologies. The principal arguments against a conversion to these ecologically more favorable alternatives were related to cost and quality.
Recently, the EU Solvent Directive (1999/13/EC) went into effect, aiming to significantly reduce industrial-solvent emissions. Up until this point, however, instruments enabling smaller companies to determine their solvent emissions and to simultaneously develop process-improvement potentials while keeping costs in mind have been missing.
Using the mass and energy flow-management approach, cost structures and environmental benefits can be made transparent to the entrepreneur. The primary result of the research projects presented here is the computer-based mass and energy flow model called the individual computer-aided mass and energy flow model for the vehicle-refinishing sector (IMPROVE). It can be used as a detailed business-consultancy tool. Based upon this, practical guidelines were developed for easy orientation and activity planning. They can be used by companies to help them fulfill the requirements of environmental legislation and to display the benefits that can be achieved by various emission-reduction measures. 相似文献
Recently, the EU Solvent Directive (1999/13/EC) went into effect, aiming to significantly reduce industrial-solvent emissions. Up until this point, however, instruments enabling smaller companies to determine their solvent emissions and to simultaneously develop process-improvement potentials while keeping costs in mind have been missing.
Using the mass and energy flow-management approach, cost structures and environmental benefits can be made transparent to the entrepreneur. The primary result of the research projects presented here is the computer-based mass and energy flow model called the individual computer-aided mass and energy flow model for the vehicle-refinishing sector (IMPROVE). It can be used as a detailed business-consultancy tool. Based upon this, practical guidelines were developed for easy orientation and activity planning. They can be used by companies to help them fulfill the requirements of environmental legislation and to display the benefits that can be achieved by various emission-reduction measures. 相似文献
28.
29.
The effects of antifouling paint leachate containing tributyltin on community metabolism and nutrient dynamics were measured in situ on natural communities dominated by Fucus vesiculosus. The measurements were made in two areas with different salinities and at various TBT concentrations up to about 5 µg 1–1. A portable continuous flow-through system was used in which the communities were incubated for a week. Continual measurements of oxygen, temperature, light and flow rate of water were made. A Perturbation Index (PI) and an Absolute Disturbance Index (ADI) were used to describe the changes due to treatment relative to the control, and to obtain a total picture of disturbance using all measured parameters. Photosynthesis was particularly strongly affected and changes were obvious in oxygen production and nutrient uptake at TBT levels as low as 0.6 µg 1–1. 相似文献
30.
A study on the profundal chironomids of the artificial Lake Campotosto (Central Italy) was carried out during the summer/early autumn of 1983 and 1984, in order to analyse their composition and community structure in relation to the lake trophic level assessed by water chemical analysis.A total of about 2000 specimens belonging to 15 taxa were collected during the study.Chironomus plumosus group andTanytarsus spp. dominated in 1983 and 1984, respectively, showing a competitive relationship probably due to the larval size. The functional feeding organization was mostly composed of collectors (percentages greater than 90%), revealing the presence of abundant fine organic deposits (FPOM). Diversity and evenness appeared to be negatively affected by the monotony of food, which seems to constitute the key factor in governing both the taxonomic and the trophic structure of chironomid fauna.A clear discrepancy between water chemical data and profundal chironomid analyses was observed in the assessment of the lake trophic level. Sediments exhibited eutrophicated conditions, whereas overlying waters indicated an oligotrophic status. The relevance of profundal macrobenthic investigations in detecting eutrophication is stressed. 相似文献