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1.
In correctly predicting that selection efficiency is positively correlated with the effective population size ( Ne), the nearly neutral theory provides a coherent understanding of between-species variation in numerous genomic parameters, including heritable error (germline mutation) rates. Does the same theory also explain variation in phenotypic error rates and in abundance of error mitigation mechanisms? Translational read-through provides a model to investigate both issues as it is common, mostly nonadaptive, and has good proxy for rate (TAA being the least leaky stop codon) and potential error mitigation via “fail-safe” 3′ additional stop codons (ASCs). Prior theory of translational read-through has suggested that when population sizes are high, weak selection for local mitigation can be effective thus predicting a positive correlation between ASC enrichment and Ne. Contra to prediction, we find that ASC enrichment is not correlated with Ne. ASC enrichment, although highly phylogenetically patchy, is, however, more common both in unicellular species and in genes expressed in unicellular modes in multicellular species. By contrast, Ne does positively correlate with TAA enrichment. These results imply that local phenotypic error rates, not local mitigation rates, are consistent with a drift barrier/nearly neutral model. 相似文献
2.
Our society faces the pressing challenge of increasing agricultural production while minimizing negative consequences on ecosystems and the global climate. Indonesia, which has pledged to reduce greenhouse gas (GHG) emissions from deforestation while doubling production of several major agricultural commodities, exemplifies this challenge. Here we focus on palm oil, the world’s most abundant vegetable oil and a commodity that has contributed significantly to Indonesia’s economy. Most oil palm expansion in the country has occurred at the expense of forests, resulting in significant GHG emissions. We examine the extent to which land management policies can resolve the apparently conflicting goals of oil palm expansion and GHG mitigation in Kalimantan, a major oil palm growing region of Indonesia. Using a logistic regression model to predict the locations of new oil palm between 2010 and 2020 we evaluate the impacts of six alternative policy scenarios on future emissions. We estimate net emissions of 128.4–211.4 MtCO 2 yr -1 under business as usual expansion of oil palm plantations. The impact of diverting new plantations to low carbon stock land depends on the design of the policy. We estimate that emissions can be reduced by 9-10% by extending the current moratorium on new concessions in primary forests and peat lands, 35% by limiting expansion on all peat and forestlands, 46% by limiting expansion to areas with moderate carbon stocks, and 55–60% by limiting expansion to areas with low carbon stocks. Our results suggest that these policies would reduce oil palm profits only moderately but would vary greatly in terms of cost-effectiveness of emissions reductions. We conclude that a carefully designed and implemented oil palm expansion plan can contribute significantly towards Indonesia’s national emissions mitigation goal, while allowing oil palm area to double. 相似文献
3.
Concern over climate change has led the U.S. to consider a cap-and-trade system to regulate emissions. Here we illustrate the land-use impact to U.S. habitat types of new energy development resulting from different U.S. energy policies. We estimated the total new land area needed by 2030 to produce energy, under current law and under various cap-and-trade policies, and then partitioned the area impacted among habitat types with geospatial data on the feasibility of production. The land-use intensity of different energy production techniques varies over three orders of magnitude, from 1.9–2.8 km 2/TW hr/yr for nuclear power to 788–1000 km 2/TW hr/yr for biodiesel from soy. In all scenarios, temperate deciduous forests and temperate grasslands will be most impacted by future energy development, although the magnitude of impact by wind, biomass, and coal to different habitat types is policy-specific. Regardless of the existence or structure of a cap-and-trade bill, at least 206,000 km 2 will be impacted without substantial increases in energy efficiency, which saves at least 7.6 km 2 per TW hr of electricity conserved annually and 27.5 km 2 per TW hr of liquid fuels conserved annually. Climate policy that reduces carbon dioxide emissions may increase the areal impact of energy, although the magnitude of this potential side effect may be substantially mitigated by increases in energy efficiency. The possibility of widespread energy sprawl increases the need for energy conservation, appropriate siting, sustainable production practices, and compensatory mitigation offsets. 相似文献
4.
Since Chinese government put a target to decrease carbon intensity 40–45% in 2020 than that of 2005, a series of emission mitigation measures has been implemented. Against this backdrop, we established a system dynamics model to investigate the energy consumption, CO 2 emission and mitigation options in China. The results show that the carbon intensity will reduce by 22.68%, 26.84%, 43.77%, and 46.65% in BaU (Business as usual), NEP (New energy policy), CTP (Carbon tax policy) and IP (Integrated policy) scenarios in 2020 compared with 2005. Obviously, Chinese government can accomplish the target under CTP and IP scenarios. Moreover, the “inflection point” in CTP and IP scenarios reveals the decision-making process between tax burden and emission reduction behavior. A brief analysis of interactive effect is accomplished by equilibrium theory and simulation results. It shows that the interactive effect of two policies, which act on the same object with same action direction, is weaker than the aggregation of two separated effects, whereas it is larger than any individual effect. In a nutshell, these findings are helpful for policymakers to optimize their policy decision-making to cut CO 2 emissions. 相似文献
5.
BackgroundThe Czech Republic has one of the poorest tobacco control records in Europe. This paper examines transnational tobacco companies'' (TTCs'') efforts to influence policy there, paying particular attention to excise policies, as high taxes are one of the most effective means of reducing tobacco consumption, and tax structures are an important aspect of TTC competitiveness. Methods and FindingsTTC documents dating from 1989 to 2004/5 were retrieved from the Legacy Tobacco Documents Library website, analysed using a socio-historical approach, and triangulated with key informant interviews and secondary data. The documents demonstrate significant industry influence over tobacco control policy. Philip Morris (PM) ignored, overturned, and weakened various attempts to restrict tobacco advertising, promoting voluntary approaches as an alternative to binding legislation. PM and British American Tobacco (BAT) lobbied separately on tobacco tax structures, each seeking to implement the structure that benefitted its own brand portfolio over that of its competitors, and enjoying success in turn. On excise levels, the different companies took a far more collaborative approach, seeking to keep tobacco taxes low and specifically to prevent any large tax increases. Collective lobbying, using a variety of arguments, was successful in delaying the tax increases required via European Union accession. Contrary to industry arguments, data show that cigarettes became more affordable post-accession and that TTCs have taken advantage of low excise duties by raising prices. Interview data suggest that TTCs enjoy high-level political support and continue to actively attempt to influence policy. ConclusionThere is clear evidence of past and ongoing TTC influence over tobacco advertising and excise policy. We conclude that this helps explain the country''s weak tobacco control record. The findings suggest there is significant scope for tobacco tax increases in the Czech Republic and that large (rather than small, incremental) increases are most effective in reducing smoking.
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6.
Attempts to meet biodiversity goals through application of the mitigation hierarchy have gained wide traction globally with increased development of public policy, lending standards, and corporate practices. With interest in biodiversity offsets increasing in Latin America, we seek to strengthen the basis for policy development through a review of major environmental licensing policy frameworks in Argentina, Brazil, Chile, Colombia, Mexico, Peru and Venezuela. Here we focused our review on an examination of national level policies to evaluate to which degree current provisions promote positive environmental outcomes. All the surveyed countries have national-level Environmental Impact Assessment laws or regulations that cover the habitats present in their territories. Although most countries enable the use of offsets only Brazil, Colombia, Mexico and Peru explicitly require their implementation. Our review has shown that while advancing quite detailed offset policies, most countries do not seem to have strong requirements regarding impact avoidance. Despite this deficiency most countries have a strong foundation from which to develop policy for biodiversity offsets, but several issues require further guidance, including how best to: (1) ensure conformance with the mitigation hierarchy; (2) identify the most environmentally preferable offsets within a landscape context; (3) determine appropriate mitigation replacement ratios; and (4) ensure appropriate time and effort is given to monitor offset performance. 相似文献
7.
In this research, structural and functional responses of benthic macroinvertebrates to mitigation measures (carried out in the dammed and polluted Duraton River, Central Spain, during the 1990s and 2000s) were examined by comparing physicochemical and biological data from the summer of 1987 with data from the summer of 2014. Mitigation measures resulted in significant increases in dissolved oxygen concentrations, as well as in significant reductions of fluoride (F −) pollution and short-term flow fluctuations. The macrobenthic community responded positively to improvements in river environmental conditions, exhibiting significant increases in abundance (total density, total biomass and EPT density) and diversity (total family richness and EPT richness) at impacted sampling sites. Furthermore, the presence of relatively sensitive benthic macroinvertebrates after mitigation measures (as indicated by increased values of BMWQ biotic indices) also was the main cause for observed reductions in the environmental impact caused by disturbance points (as indicated by decreased values of the EI index), and for the observed recovering of the trophic structure of the macrobenthic community, with macroinvertebrate scrapers as the functional feeding group most favored. These macroinvertebrate responses to mitigation measures were more marked at sampling sites that initially were more impacted (i.e., nearest to disturbance points), and less apparent at the sampling site that initially was less impacted (i.e., farthest to disturbance points). Within the hydropsychid assemblage, improvements in river environmental conditions clearly favored the presence of Hydropsyche pellucidula and Cheumatopsyche lepida at the expense of the other hydropsychid species. In spite of all monitored environmental improvements and macroinvertebrate positive responses, the need for additional mitigation measures was evident, particularly to reduce high turbidity levels and sedimentation of fine inorganic matter negatively affecting benthic macroinvertebrates downstream from the industrial effluent. Overall, it is concluded that the multimetric approach is an effective technique to assess macroinvertebrate responses to mitigation measures in river ecosystems. 相似文献
8.
Although COVID-19 emerged as a global shock, governments adopted non-pharmaceutical policy responses that were rather heterogeneous, depending on cultural and institutional characteristics. At the country level, the stringency of ‘lockdown’-type policies should be set to achieve the best possible trade-off between economic and fatality dynamics, obviously accounting for possible cross-border influences. To allow for policy learning, I assume that the first country implementing a policy initiative that is worth emulating must either get the best possible health or the best possible economic outcome. I propose a combination of sign and magnitude restrictions, embedded in a global VAR model, to identify idiosyncratic policy shocks that spill over and influence policy responses abroad. Once policy shocks are identified, I run a comparison exercise between two model specifications, i.e. with and without policy emulation. Within a given a sample, this methodology can be used to find when and where policy lessons can be identified. I find that, among 17 developed and developing countries, few can offer lessons based on their policy initiatives, but several others might get better trade-offs through policy emulation, although in reality this outcome is not guaranteed to have occurred. 相似文献
9.
BackgroundSuboptimal medicine use is a global public health problem. For 35 years the World Health Organization (WHO) has promoted essential medicines policies to improve quality use of medicines (QUM), but evidence of their effectiveness is lacking, and uptake by countries remains low. Our objective was to determine whether WHO essential medicines policies are associated with better QUM. Methods and FindingsWe compared results from independently conducted medicines use surveys in countries that did versus did not report implementation of WHO essential medicines policies. We extracted survey data on ten validated QUM indicators and 36 self-reported policy implementation variables from WHO databases for 2002–2008. We calculated the average difference (as percent) for the QUM indicators between countries reporting versus not reporting implementation of specific policies. Policies associated with positive effects were included in a regression of a composite QUM score on total numbers of implemented policies. Data were available for 56 countries. Twenty-seven policies were associated with better use of at least two percentage points. Eighteen policies were associated with significantly better use (unadjusted p<0.05), of which four were associated with positive differences of 10% or more: undergraduate training of doctors in standard treatment guidelines, undergraduate training of nurses in standard treatment guidelines, the ministry of health having a unit promoting rational use of medicines, and provision of essential medicines free at point of care to all patients. In regression analyses national wealth was positively associated with the composite QUM score and the number of policies reported as being implemented in that country. There was a positive correlation between the number of policies (out of the 27 policies with an effect size of 2% or more) that countries reported implementing and the composite QUM score ( r = 0.39, 95% CI 0.14 to 0.59, p = 0.003). This correlation weakened but remained significant after inclusion of national wealth in multiple linear regression analyses. Multiple policies were more strongly associated with the QUM score in the 28 countries with gross national income per capita below the median value (US$2,333) ( r = 0.43, 95% CI 0.06 to 0.69, p = 0.023) than in the 28 countries with values above the median ( r = 0.22, 95% CI −0.15 to 0.56, p = 0.261). The main limitations of the study are the reliance on self-report of policy implementation and measures of medicine use from small surveys. While the data can be used to explore the association of essential medicines policies with medicine use, they cannot be used to compare or benchmark individual country performance. ConclusionsWHO essential medicines policies are associated with improved QUM, particularly in low-income countries.
Please see later in the article for the Editors'' Summary 相似文献
10.
Under the Kyoto Protocol, the European Union is committed to a reduction in CO 2 emissions to 92% of baseline (1990) levels during the first commitment period (2008–2012). The Kyoto Protocol allows carbon emissions to be offset by demonstrable removal of carbon from the atmosphere. Thus, land‐use/land‐management change and forestry activities that are shown to reduce atmospheric CO 2 levels can be included in the Kyoto targets. These activities include afforestation, reforestation and deforestation (article 3.3 of the Kyoto Protocol) and the improved management of agricultural soils (article 3.4). In this paper, we estimate the carbon mitigation potential of various agricultural land‐management strategies and examine the consequences of European policy options on carbon mitigation potential, by examining combinations of changes in agricultural land‐use/land‐management. We show that no single land‐management change in isolation can mitigate all of the carbon needed to meet Europe's climate change commitments, but integrated combinations of land‐management strategies show considerable potential for carbon mitigation. Three of the combined scenarios, one of which is an optimal realistic scenario, are by themselves able to meet Europe's emission limitation or reduction commitments. Through combined land‐management scenarios, we show that the most important resource for carbon mitigation in agriculture is the surplus arable land. We conclude that in order to fully exploit the potential of arable land for carbon mitigation, policies will need to be implemented to allow surplus arable land to be put into alternative long‐term land‐use. Of all options examined, bioenergy crops show the greatest potential for carbon mitigation. Bioenergy crop production also shows an indefinite mitigation potential compared to other options where the mitigation potential is finite. We suggest that in order to exploit fully the bioenergy option, the infrastructure for bioenergy production needs to be significantly enhanced before the beginning of the first Kyoto commitment period in 2008. It is not expected that Europe will attempt to meet its climate change commitments solely through changes in agricultural land‐use. A reduction in CO 2‐carbon emissions will be key to meeting Europe's Kyoto targets, and forestry activities (Kyoto Article 3.3) will play a major role. In this study, however, we demonstrate the considerable potential of changes in agricultural land‐use and ‐management (Kyoto Article 3.4) for carbon mitigation and highlight the policies needed to promote these agricultural activities. As all sources of carbon mitigation will be important in meeting Europe's climate change commitments, agricultural carbon mitigation options should be taken very seriously. 相似文献
11.
BackgroundBrazil has reduced its smoking rate by about 50% in the last 20 y. During that time period, strong tobacco control policies were implemented. This paper estimates the effect of these stricter policies on smoking prevalence and associated premature mortality, and the effect that additional policies may have. Methods and FindingsThe model was developed using the SimSmoke tobacco control policy model. Using policy, population, and smoking data for Brazil, the model assesses the effect on premature deaths of cigarette taxes, smoke-free air laws, mass media campaigns, marketing restrictions, packaging requirements, cessation treatment programs, and youth access restrictions. We estimate the effect of past policies relative to a counterfactual of policies kept to 1989 levels, and the effect of stricter future policies. Male and female smoking prevalence in Brazil have fallen by about half since 1989, which represents a 46% (lower and upper bounds: 28%–66%) relative reduction compared to the 2010 prevalence under the counterfactual scenario of policies held to 1989 levels. Almost half of that 46% reduction is explained by price increases, 14% by smoke-free air laws, 14% by marketing restrictions, 8% by health warnings, 6% by mass media campaigns, and 10% by cessation treatment programs. As a result of the past policies, a total of almost 420,000 (260,000–715,000) deaths had been averted by 2010, increasing to almost 7 million (4.5 million–10.3 million) deaths projected by 2050. Comparing future implementation of a set of stricter policies to a scenario with 2010 policies held constant, smoking prevalence by 2050 could be reduced by another 39% (29%–54%), and 1.3 million (0.9 million–2.0 million) out of 9 million future premature deaths could be averted. ConclusionsBrazil provides one of the outstanding public health success stories in reducing deaths due to smoking, and serves as a model for other low and middle income nations. However, a set of stricter policies could further reduce smoking and save many additional lives.
Please see later in the article for the Editors'' Summary 相似文献
12.
BackgroundProfessional societies use metrics to evaluate medical schools'' policies regarding interactions of students and faculty with the pharmaceutical and medical device industries. We compared these metrics and determined which US medical schools'' industry interaction policies were associated with student behaviors. Methods and FindingsUsing survey responses from a national sample of 1,610 US medical students, we compared their reported industry interactions with their schools'' American Medical Student Association (AMSA) PharmFree Scorecard and average Institute on Medicine as a Profession (IMAP) Conflicts of Interest Policy Database score. We used hierarchical logistic regression models to determine the association between policies and students'' gift acceptance, interactions with marketing representatives, and perceived adequacy of faculty–industry separation. We adjusted for year in training, medical school size, and level of US National Institutes of Health (NIH) funding. We used LASSO regression models to identify specific policies associated with the outcomes. We found that IMAP and AMSA scores had similar median values (1.75 [interquartile range 1.50–2.00] versus 1.77 [1.50–2.18], adjusted to compare scores on the same scale). Scores on AMSA and IMAP shared policy dimensions were not closely correlated (gift policies, r = 0.28, 95% CI 0.11–0.44; marketing representative access policies, r = 0.51, 95% CI 0.36–0.63). Students from schools with the most stringent industry interaction policies were less likely to report receiving gifts (AMSA score, odds ratio [OR]: 0.37, 95% CI 0.19–0.72; IMAP score, OR 0.45, 95% CI 0.19–1.04) and less likely to interact with marketing representatives (AMSA score, OR 0.33, 95% CI 0.15–0.69; IMAP score, OR 0.37, 95% CI 0.14–0.95) than students from schools with the lowest ranked policy scores. The association became nonsignificant when fully adjusted for NIH funding level, whereas adjusting for year of education, size of school, and publicly versus privately funded school did not alter the association. Policies limiting gifts, meals, and speaking bureaus were associated with students reporting having not received gifts and having not interacted with marketing representatives. Policy dimensions reflecting the regulation of industry involvement in educational activities (e.g., continuing medical education, travel compensation, and scholarships) were associated with perceived separation between faculty and industry. The study is limited by potential for recall bias and the cross-sectional nature of the survey, as school curricula and industry interaction policies may have changed since the time of the survey administration and study analysis. ConclusionsAs medical schools review policies regulating medical students'' industry interactions, limitations on receipt of gifts and meals and participation of faculty in speaking bureaus should be emphasized, and policy makers should pay greater attention to less research-intensive institutions.
Please see later in the article for the Editors'' Summary 相似文献
13.
PurposeIn recent years, the building sector has highlighted the importance of operational energy and efficient resource management in order to reduce the environmental impacts of buildings. However, differences in building-specific properties (building location, size, construction material, etc.) pose a major challenge in development of generic policy on buildings. The aim of this study was to investigate the relationship between energy and resource management policies, and building-specific characteristics on environmental impacts of refurbished office buildings in New Zealand. MethodsLife Cycle Assessment (LCA) was performed for 17 office buildings operating under seven representative climatic conditions found in New Zealand. Each building was assessed under four policy scenarios: (i) business-as-usual, (ii) use of on-site photovoltaic (PV) panels, (iii) electricity supply from a renewable energy grid, and (iv) best practice construction activities adopted at site. The influence of 15 building-specific characteristics in combination with each scenario was evaluated. The study adopted regression analysis, more specifically Kruskal-Wallis and General Additive Modeling (GAM), to support interpretation of the LCA results. Results and discussionAll the chosen policies can significantly contribute to climate change mitigation as compared to business-as-usual. However, the Kruskal-Wallis results highlight policies on increasing renewable energy sources supplying national grid electricity can substantially reduce the impacts across most environmental impact categories. Better construction practices should be prioritized over PV installation as use of on-site PV significantly increases the environmental impacts related to use of resources. The GAM results show on-site PV could be installed in low-rise buildings in regions with long sunshine hours. The results also show the strong influence of façade elements and technical equipment in determining the environmental performance of small and large buildings, respectively. In large multi-storied buildings, efficient HVAC and smaller window area are beneficial features, while in small buildings the choice of façade materials with low embodied impacts should be prioritized. ConclusionsIn general, the study highlighted the importance of policies on increasing renewable energy supply from national grid electricity to substantially reduce most of the impacts related to buildings. In addition, the study also highlighted the importance of better construction practices and building-specific characteristics to reduce the impacts related to resource use. These findings can support policy makers to prioritize strategies to improve the environmental performance of existing buildings in New Zealand and in regions with similar building construction and climate. 相似文献
14.
Since Canada’s accession to the Ramsar Convention on Wetlands in 1981, the nation’s commitment to wetland conservation and
management has increased significantly. This includes the adoption of one of the World’s first national wetland conservation
policies by the Government of Canada, and the adoption of complementary policy and legislative initiatives by most of the
13 provincial and territorial jurisdictions. Numerous habitat ‘no net loss’ and environmental assessment policies, regulations
and guidelines for incorporating mitigation processes into development decisions affecting wetland resources are used throughout
Canada. The governments of Canada and six provinces have so far adopted wetland mitigation measures. These are in addition
to comprehensive wetland fish and wildlife habitat initiatives, such as the species and habitat joint ventures delivered in
Canada through the North American Waterfowl Management Plan by all jurisdictions and numerous non-government partners. This
paper examines the current policies, regulations and programs, as well as past implementation experience with wetland mitigation
and compensation in Canada. 相似文献
15.
Overfishing, pollution and other environmental factors have greatly reduced commercially valuable stocks of fish. In a 2006 Science article, a group of ecologists and economists warned that the world may run out of seafood from natural stocks if overfishing continues at current rates. In this paper, we explore the interaction between a constant proportion harvest policy and recruitment dynamics. We examine the discrete-time constant proportion harvest policy discussed in Ang et al. (2009) and then expand the framework to include stock-recruitment functions that are compensatory and overcompensatory, both with and without the Allee effect.We focus on constant proportion policies (CPPs). CPPs have the potential to stabilize complex overcompensatory stock dynamics, with or without the Allee effect, provided the rates of harvest stay below a threshold. If that threshold is exceeded, CPPs are known to result in the sudden collapse of a fish stock when stock recruitment exhibits the Allee effect. In case studies, we analyze CPPs as they might be applied to Gulf of Alaska Pacific halibut fishery and the Georges Bank Atlantic cod fishery based on harvest rates from 1975 to 2007. The best fit models suggest that, under high fishing mortalities, the halibut fishery is vulnerable to sudden population collapse while the cod fishery is vulnerable to steady decline to zero. The models also suggest that CPP with mean harvesting levels from the last 30 years can be effective at preventing collapse in the halibut fishery, but these same policies would lead to steady decline to zero in the Atlantic cod fishery. We observe that the likelihood of collapse in both fisheries increases with increased stochasticity (for example, weather variability) as predicted by models of global climate change. 相似文献
16.
The spatial diversity and distribution of AM fungi were investigated in three plots located in farming–pastoral zone, north China. The rhizospheres of Caragana korshinskii, Artemisia sphaerocephala and Salix psammophila were sampled and thirty AM fungal species belonging to five genera were isolated. The study demonstrated that AM fungal diversity and distribution differed significantly among the three host plants and the three studied plots. Spore density of AM fungi ranged between 2 and 22 spores per g ?1 of soil and species richness between 8 and 23. Correlation coefficient analysis demonstrated that spore density was significantly and positively correlated with soil organic matter and available N ( P?<?0.01). Species richness was significantly and positively correlated with soil organic matter and available P ( P?<?0.01), but significantly and negatively correlated with soil pH ( P?<?0.01). Finally, the Shannon–Weiner index was significantly and positively correlated with soil organic matter ( P?<?0.05). In this farming–pastoral zone, Glomus reticulatum and G. melanosporum may be more adaptable to the arid conditions than other AM fungal species. This research into AM fungal diversity may lead to exploitation of AM fungi for the mitigation of soil erosion and desertification using mycorrhizal plants, such as C.korshinskii, A. sphaerocephala and S. psammophila. The results of this study support the conclusion that diversity and distribution of AM fungi might be useful to monitor desertification and soil degradation. 相似文献
17.
This paper gives a quantitative analysis on the non-CO2 emissions related to energy demand, energy activities and land use change of six scenarios with different development pattern in 2030 and 2050 based on IPAC emission model. The various mitigation technologies and policies are assessed to understand the corresponding non-CO2 emission reduction effect. The research shows that the future non-CO2 emissions of China will grow along with increasing energy demand, in which thermal power and transportation will be the major emission and mitigation sectors. During the cause of future social and economic development, the control and mitigation of non-CO2 emissions is a problem as challenging and pressing as that of CO2 emissions. This study indicates that the energy efficiency improvement, renewable energy, advanced nuclear power generation, fuel cell, coal-fired combined cycle, clean coal and motor vehicle emission control technologies will contribute to non-CO2 emissions control and mitigation. 相似文献
18.
ObjectivesWe examined whether state laws and district policies pertaining to nutritional restrictions on school fundraisers were associated with school policies as reported by administrators in a nationally-representative sample of United States public elementary schools. MethodsWe gathered data on school-level fundraising policies via a mail-back survey during the 2009–10 and 2010–11 school years. Surveys were received from 1,278 public elementary schools (response rate = 60.9%). Data were also gathered on corresponding school district policies and state laws. After removing cases with missing data, the sample size for analysis was 1,215 schools. ResultsAfter controlling for school characteristics, school policies were consistently associated with state laws and district policies, both those pertaining to fundraising generally, as well as specific restrictions on the sale of candy and soda in fundraisers (all Odds Ratios >2.0 and Ps<.05). However, even where district policies and state laws required fundraising restrictions, school policies were not uniformly present; school policies were also in place at only 55.8% of these schools, but were more common at schools in the West (77.1%) and at majority-Latino schools (71.4%), indicating uneven school-level implementation of district policy and state law. ConclusionsDistrict policies and state laws were associated with a higher prevalence of elementary school-level fundraising policies, but many schools that were subject to district policies and state laws did not have school-level restrictions in place, suggesting the need for further attention to factors hindering policy implementation in schools. 相似文献
20.
The evaluation of how the gut microbiota affects both methane emissions and animal production is necessary in order to achieve methane mitigation without production losses. Toward this goal, the aim of this study was to correlate the rumen microbial communities (bacteria, archaea, and fungi) of high (HP), medium (MP), and low milk producing (LP), as well as dry (DC), Holstein dairy cows in an actual tropical production system with methane emissions and animal production traits. Overall, DC cows emitted more methane, followed by MP, HP and LP cows, although HP and LP cow emissions were similar. Using next-generation sequencing, it was found that bacteria affiliated with Christensenellaceae, Mogibacteriaceae, S24-7, Butyrivibrio, Schwartzia, and Treponema were negatively correlated with methane emissions and showed positive correlations with digestible dry matter intake (dDMI) and digestible organic matter intake (dOMI). Similar findings were observed for archaea in the genus Methanosphaera. The bacterial groups Coriobacteriaceae, RFP12, and Clostridium were negatively correlated with methane, but did not correlate with dDMI and dOMI. For anaerobic fungal communities, no significant correlations with methane or animal production traits were found. Based on these findings, it is suggested that manipulation of the abundances of these microbial taxa may be useful for modulating methane emissions without negatively affecting animal production. 相似文献
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