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1.
《Autophagy》2013,9(12):1822-1823
Mitochondrial DNA (mtDNA) is different in many ways from nuclear DNA. A key difference is that certain types of DNA damage are not repaired in the mitochondrial genome. What, then, is the fate of such damage? What are the effects? Both questions are important from a health perspective because irreparable mtDNA damage is caused by many common environmental stressors including ultraviolet C radiation (UVC). We found that UVC-induced mtDNA damage is removed slowly in the nematode Caenorhabditis elegans via a mechanism dependent on mitochondrial fusion, fission, and autophagy. However, knockdown or knockout of genes involved in these processes—many of which have homologs involved in human mitochondrial diseases—had very different effects on the organismal response to UVC. Reduced mitochondrial fission and autophagy caused no or small effects, while reduced mitochondrial fusion had dramatic effects.  相似文献   

2.
Transgenic crops are being adopted rapidly at the global level, but only a few developing countries are growing them in significant quantities. Why are these crops so successful in some countries but not in others? Farm level profitability ultimately determines whether farmers adopt and retain a new technology, but this depends on much more than technical performance. Recent economic studies in developing countries find positive, but highly variable, economic returns to adopting transgenic crops. These studies confirm that institutional factors such as national agricultural research capacity, environmental and food safety regulations, intellectual property rights and agricultural input markets matter at least as much as the technology itself in determining the level and distribution of economic benefits.  相似文献   

3.
As we come to the end of 2011, Genome Biology has asked some members of our Editorial Board for their views on the state of play in genomics. What was their favorite paper of 2011? What are the challenges in their particular research area? Who has had the biggest influence on their careers? What advice would they give to young researchers embarking on a career in research?  相似文献   

4.
China's high‐speed economic development and reliance on overconsumption of natural resources have led to serious environmental pollution. Environmental taxation is seen as an effective economic tool to help mitigate air pollution. In order to assess the effects of different scenarios of environmental taxation policies, we propose a frontier‐based environmentally extended input–output optimization model with explicit emission abatement sectors to reflect the inputs and benefits of abatement. Frontier analysis ensures policy scenarios are assessed under the same technical efficiency benchmark, while input–output analysis depicts the wide range of economic transactions among sectors of an economy. Four scenarios are considered in this study, which are increasing specific tax rates of SO2, NOx, and soot and dust separately and increasing all three tax rates simultaneously. Our estimation results show that: raising tax rates of SO2, NOx, and soot and dust simultaneously would have the highest emission reduction effects, with the SO2 tax rate making the greatest contribution to emission reduction. Raising the soot and dust tax rate is the most environmentally friendly strategy due to its highest abatement to welfare through avoided health costs. The combination of frontier analysis and input–output analysis provides policy makers a comprehensive and sectoral approach to assess costs and benefits of environmental taxation.  相似文献   

5.
Invasive species typically establish in areas outside their natural distribution through accidental introduction and accidental release or escape. Some species are introduced legally for economic and social benefits such as recreational hunting, the pet trade and research through established permitting processes driven by appropriate laws and regulations. The aim of this study was to determine whether there is a trend in demand for regulated alien taxa based on permit requests and to ascertain the activities for which permits requested in order to infer the drivers of alien taxa demand in South Africa. We examined the Department of Environmental Affairs (DEA) species permitting application database records from October 2015 to February 2018. From the total of 1,390 permit applications during this period, 79.2% of the permits were issued for various economic and social activities associated with the following species: Red lechwe (Kobus leche leche, Gray), fallow deer (Dama dama Linnaeus), Grass carp (Ctenopharyngodon idella Valenciennes), Nile tilapia (Oreochromis niloticus Linnaeus) and rose-ring parakeet (Psittacula krameri Scopoli). Our results suggest that economic activities such as hunting and sport fishing are driving the demand for some regulated species. We suggest reinforced monitoring and inspection for permit compliance for species sought to minimise potential escape.  相似文献   

6.
Question: What are the changes associated with the recent invasion by the non‐native legume, Cytisus scoparius? Location: Subalpine vegetation (1500 m a.s.l.) in Australia. Methods: We used multivariate techniques and regression analyses to assess vegetation and environmental changes across six study sites. Vegetation and environmental variables were investigated at three different stages of invasion: (1) recent invasion (8–10 yr), (2) mature invasion (15–16 yr) and (3) long‐term invasion (25 yr). Results: Substantial changes in floristic composition and species richness were evident after 15 yr and these changes became more pronounced after 25 yr. Changes due to invasion were associated with a dramatic loss of native species or a reduction in their abundance. No ‘new species’ were evident under invaded stands. Forbs were most affected by the establishment of C. scoparius, although all growth forms responded negatively. Dense canopy shading and an increasingly dense, homogeneous litter layer in the understorey as a result of C. scoparius were strong environmental drivers of vegetation change. Greenhouse studies confirmed the importance of these processes on the germination and growth of two native species. Conclusions: This study highlights the potential for C. scoparius to alter both vegetation and environmental processes in the subalpine region.  相似文献   

7.
Background: This article describes the types of community‐wide benefits provided by investigators conducting public health research in South Asia as well as their self‐reported reasons for providing such benefits. Methods: We conducted 52 in‐depth interviews to explore how public health investigators in low‐resource settings make decisions about the delivery of ancillary care to research subjects. In 39 of the interviews respondents described providing benefits to members of the community in which they conducted their study. We returned to our narrative dataset to find answers to two questions: What types of community‐wide benefits do researchers provide when conducting public health intervention studies in the community setting, and what reasons do researchers give when asked why they provided community‐wide benefits? Findings: The types of community‐wide benefits delivered were directed to the health and well‐being of the population. The most common types of benefits delivered were the facilitation of access to health care for individuals in acute medical need and emergency response to natural disasters. Respondents' self‐reported reasons when asked why they provided such benefits fell into 2 general categories: intrinsic importance and instrumental importance.  相似文献   

8.
This paper is based on research amongst a community of marginalised Hindu women in the holy city of Vārānas? in North India. It focuses on a case study in which an abandoned baby girl, who was found on the banks of the Ganges by one of these women, subsequently could be created as a living goddess. It describes and analyses the manner in which such a religious belief was generated and sustained in this community but, more importantly, how the complex social and psychological processes through which the generation of such a belief enabled many of these marginalised women to sustain a self‐understanding—assailed by powerful rival status groups—of being imbued with power (?akti) like their goddess. Further, women were described to me, by men and by women, as being in themselves specific kinds of ?aktis. During the course of my field research, it became apparent that the ?akti of Hindu females of all ages is understood, at various levels of consciousness, to be an immense and accessible reservoir of power. Hence, this paper explores how ?akti offers others opportunities, by annexing it, to fulfill various kinds of desires.  相似文献   

9.
Research on the structure of an individual's mental lexicon has shown that, among the set of concepts belonging to a single semantic field, there is typically one particular concept that stands out. The processes of storage, identification, and retrieval of this concept are faster and more successful than they are for the others. For example, in the vertical hierarchy of the concept fruit—apple—antonovka [McIntosh to give a familiar U. S. example—Trans.], apple plays this type of lead role and also occupies the most prominent position in the horizontal series apple—pear—plum—cherries—orange. Concepts with such characteristics are referred to as basic, source, or primary concepts. What is the reason for their special status?  相似文献   

10.
Air emissions from the U.S. pulp and paper sector have been federally regulated since 1978; however, regulations are periodically reviewed and revised to improve efficiency and effectiveness of existing emission standards. The Industrial Sectors Integrated Solutions (ISIS) model for the pulp and paper sector is currently under development at the U.S. Environmental Protection Agency (EPA), and can be utilized to facilitate multi-pollutant, sector-based analyses that are performed in conjunction with regulatory development. The model utilizes a multi-sector, multi-product dynamic linear modeling framework that evaluates the economic impact of emission reduction strategies for multiple air pollutants. The ISIS model considers facility-level economic, environmental, and technical parameters, as well as sector-level market data, to estimate the impacts of environmental regulations on the pulp and paper industry. Specifically, the model can be used to estimate U.S. and global market impacts of new or more stringent air regulations, such as impacts on product price, exports and imports, market demands, capital investment, and mill closures. One major challenge to developing a representative model is the need for an extensive amount of data. This article discusses the collection and processing of data for use in the model, as well as the methods used for building the ISIS pulp and paper database that facilitates the required analyses to support the air quality management of the pulp and paper sector.  相似文献   

11.
R. Pietra 《PSN》2007,5(4):220-228
While the name of Paul Valery is usually associated with that of Leonardo da Vinci or the character, Monsieur Teste, most people are unaware of Valery’s posthumous work, which he considered the most significant of his writings: Cahiers/Notebooks, a voluminous and dense work, in its dimensions (around 30,000 pages) as well as in what it discloses about the daily ponderings of a man who considered himself — in spite of himself — a philosopher. It is a multifaceted work, touching on all fields of thought: history, politics, and the sciences, in all their diversity, from mathematics to physics, and biology to the theory of evolution. Neither philosophy, nor theology, nor linguistics is left in the dark. But he clearly expressed a preference for psychology and, more specifically, the question of mental function: What is it to think? How does the mind link ideas? What is abstraction? What role do feelings play? What is the relationship between the mind and the machine? Must we concede the existence of the unconscious mind. These are some of the questions we address in elucidating the concept of automatism through what makes it work as well as its failings.  相似文献   

12.
Plants that have evolved to survive on metal‐rich soils—metallophytes—have key values that must drive research of their unique properties and ultimately their conservation. The ability of metallophytes to tolerate extreme metal concentrations commends them for revegetation of mines and metal‐contaminated sites. Metallophytes can also be exploited in environmental technologies, for example, phytostabilization, phytoremediation, and phytomining. Actions towards conserving metallophyte species are imperative, as metallophytes are increasingly under threat of extinction from mining activity. Although many hundreds of papers describe both the biology and applications of metallophytes, few have investigated the urgent need to conserve these unique species. This paper identifies the current state of metallophyte research, and advocates future research needs for the conservation of metallophyte biodiversity and the sustainable uses of metallophyte species in restoration, rehabilitation, contaminated site remediation, and other nascent phytotechnologies. Six fundamental questions are addressed: (1) Is enough known about the global status of metallophytes to ensure their conservation? (2) Are metallophytes threatened by the activities of the minerals industry, and can their potential for the restoration or rehabilitation of mined and disturbed land be realized? (3) What problems exist in gaining prior informed consent to access metallophyte genetic resources and how can the benefits arising from their uses be equitably shared? (4) What potential do metallophytes offer as a resource base for phytotechnologies? (5) Can genetic modification be used to “design” metallophytes to use in the remediation of contaminated land? (6) Does the prospect of using metallophytes in site remediation and restoration raise ethical issues?  相似文献   

13.
Reducing greenhouse gas emissions requires a transformation of capital assets in the economy, especially those for energy supply. This paper explores the hypothesis that economically efficient decarbonization occurs when the demand for fossil fuels declines at the same rate as their capital assets depreciate. In theory this means that new investments in fossil fuel assets are avoided, but without incurring stranded assets. We examine the practicality of this hypothesis using a biophysical economic model of the US energy supply system, with an example focused on impacts of electric vehicles on the petroleum supply chain. We specifically address two questions: (1) What rate of market penetration for electric vehicles is necessary to avoid investments in the petroleum-related assets? (2) How do the costs of upstream capital assets change with the transformation to electric vehicles? High annual depreciation rates for oil refineries (δ = 9.47%) and assets for crude oil extraction (δ = 8.23%) have important impacts on results. To avoid new investment in oil refining assets through widespread electrification of light-duty vehicles, the vehicle stock would need to be transformed in just 4 or 5 years. Under most scenarios, some petroleum pipelines will likely become stranded assets due to their low rate of depreciation (δ = 2.48%). In some scenarios, additional investments in wind and solar power generation surpass oil and gas extraction for about 5 years during the transformation to electric vehicles. Once built, however, wind and solar capital assets last longer, as shown by their low rate of depreciation (δ = 3.26%).  相似文献   

14.
In 2005, a hurricane named Katrina hit the states of Louisiana and Mississippi in the US, destroying properties and flooding areas. Many people left the region and still have not returned. While some of these people may eventually return, some may not, becoming “migrants.” Assuming this phenomenon will occur, is it unique? What is the role of the environment in migration? Can there be violent conflict between such migrants and residents in areas absorbing migrants? We evaluate these questions in the cases of Hurricane Katrina, the US Dust Bowl in the 1930s, and Bangladesh since the 1950s, demonstrating that environmental change can trigger large out-migration, which can cause violent conflict in areas receiving migrants. These findings have important policy implications. Climate change is expected to degrade the environment considerably in this century. Minimizing climate change-induced migration and violent conflict in receiving areas requires an engineered economic slowdown in the developed countries, and population stabilization and economic growth in the developing countries financed by the developed countries.  相似文献   

15.
When a community authorizes the development of a controversial project which may produce adverse ecological effects, the decision may be made on the basis of a differing geographical distribution of costs and benefits. Local benefits may exceed local costs while overall costs exceed overall benefits. This paper attempts, through a mathematical theoretical exposition, to show that this situation provides a rational incentive for hypocritical public behavior. Possible solutions are considered. One set of solutions implies return to laissez-fairetype capitalism and the maintenance of a taut, spatial economic system which is sensitive to shock. Another set of solutions implies the development of a socialist economy. Mixed solutions are presented as unstable and tending to environmental deterioration. The mirrorimage problem — of concentrated costs and diffused benefits in the United States, and the State of New Jersey specifically — is also considered, leading to similar conclusions.  相似文献   

16.
Ben Schwan 《Bioethics》2021,35(1):6-14
It is natural to think that there is a tight connection between whether someone is responsible for some outcome and whether it is appropriate to hold her accountable for that outcome. And this natural thought naturally extends to health: if someone is responsible for her health, then, all else being equal, she is accountable for it. Given this, some have thought that responsibility for health has an important role to play in distributing the benefits and burdens of healthcare. But there is a reason for caution. That health is influenced by social, economic, and environmental factors is a matter of consensus. And some have argued that in light of these social determinants of health, individuals are not typically responsible for their health, rendering inappropriate policies that employ a responsibility‐for‐health criterion. This debate implicates a number of overlapping concepts and questions that are often difficult to pull apart. And I worry that those who maintain that social determinants undermine responsibility for health have latched on to the wrong target. The social determinants of health are relevant to such policies, but, I argue, not by globally undermining responsibility. Rather, social determinants are sometimes responsibility‐undermining, sometimes responsibility‐preserving, and often relevant to whether we should hold individuals accountable for their health regardless of their responsibility. This calls for a more nuanced appraisal of the ways in which the social determinants of health are relevant to such policies. And here I attempt to provide one.  相似文献   

17.
Substance flow analysis (SFA) is a frequently used industrial ecology technique for studying societal metal flows, but it is limited in its ability to inform us about future developments in metal flow patterns and how we can affect them. Equation‐based simulation modeling techniques, such as dynamic SFA and system dynamics, can usefully complement static SFA studies in this respect, but they are also restricted in several ways. The objective of this article is to demonstrate the ability of agent‐based modeling to overcome these limitations and its usefulness as a tool for studying societal metal flow systems. The body of the article summarizes the parallel implementation of two models—an agent‐based model and a system dynamics model—both addressing the following research question: What conditions foster the development of a closed‐loop flow network for metals in mobile phones? The results from in silico experimentation with these models highlight three important differences between agent‐based modeling (ABM) and equation‐based modeling (EBM) techniques. An analysis of how these differences affected the insights that could be extracted from the constructed models points to several key advantages of ABM in the study of metal flow systems. In particular, this analysis suggests that a key advantage of the ABM technique is its flexibility to enable the representation of societal metal flow systems in a more native manner. This added flexibility endows modelers with enhanced leverage to identify options for steering metal flows and opens new opportunities for using the metaphor of an ecosystem to understand metal flow systems more fully.  相似文献   

18.
What are the effects that genetics has had on Anthropological research and how can we think anthropologically about Genetics? Just as genetic data have encouraged new hypotheses about human phenotypic variation, evolutionary history, population interaction, and environmental effects, so too has Anthropology offered to genetic studies a new interpretive locus in its history and perspective. This introduction examines how the fields of Anthropology and Genetics have arrived at a crucial moment at which their interaction requires careful examination and critical reflection. The papers discussed here exemplify how we may engage in such a trans-disciplinary conversation. They speak to the future of thoughtful interaction between genetic and anthropological literature and seek a new integration that embodies the holism of the human biological sciences.  相似文献   

19.

Purpose

Sugarcane bagasse is one of the main agro-industrial residues which can be used to produce wood-based panels. However, more investigations related to its environmental performance assessment are needed, focusing on questions such as: Does it provide environmental benefits? What are its main environmental impacts? Could it substitute wood as raw material? Accordingly, this paper presents a life cycle assessment (LCA) study of particle board manufactured with sugarcane bagasse residues.

Methods

The cradle-to-gate assessment of 1 m3 of particle board made with sugarcane bagasse (PSB) considered three main subsystems: bagasse generation, bagasse distribution, and PSB production. For the inventory of PSB, dataset from two previous LCA studies related to the conventional particle board production and the ethanol life cycle for the Brazilian context were used. The allocation criterion for the bagasse generation subsystem was 9.08 % (economic base). The potential environmental impact phase was assessed by applying the CML and USEtox methods. PSB was compared with the conventional particle board manufactured in Brazil by the categories of the CML and USETox, and including land use indicators. Finally, two scenarios were analyzed to evaluate the influence of the allocation criteria and the consumption of sugarcane bagasse.

Results and discussion

All hotspots identified by CML and USETox methods are mainly related to the PSB production subsystem (24–100 % of impacts) due to heavy fuel oil, electricity, and urea-formaldehyde resin supply chain. The bagasse generation subsystem was more relevant to the eutrophication category (75 % of impacts). The bagasse distribution subsystem was not relevant because the impacts on all categories were lower than 1 %. PSB can substitute the conventional particle board mainly because of its lower contribution to abiotic depletion and ecotoxicity. Regarding land use impacts, PSB showed lower values according to all indicators (38–40 % of all impacts), which is explained by the lower demand for land occupation in comparison to that of the traditional particle board.

Conclusions

PSB can replace the traditional particle board due to its better environmental performance. The analysis of the economic allocation criterion was relevant only for the EP category, being important to reduce diesel and N-based fertilizers use during sugarcane cultivation. Regarding the influence of the sugarcane bagasse consumption, it is suggested that the sugarcane bagasse be mixed up to 75 % during particle board manufacturing so that good quality properties and environmental performance of panels can be provided.  相似文献   

20.
ABSTRACT

Gladstone, Queensland, is one of Australia’s largest coal ports and the site of many industries. Few of the 65,000 residents of the region are socially and economically independent of the fossil fuel industry. Environmental engagement is fragmented. The city epitomises, in a striking way, the double bind of growth and sustainability. The Australian environmental movement is generally seen as distant and irrelevant to local concerns. The article analyses conditions for, forms of and implications of environmental engagement in a city where coal, gas and industry are taken for granted as necessary conditions for prosperity and economic security. To what extent are ecological relevant to the residents; and how can they be dealt with within the parameters that define their lifeworlds? What can the Gladstone experience teach us about possible solutions to the double bind of growth and sustainability?  相似文献   

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