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1.
The present study investigated the influence of electromagnetic fields (EMF), similar to that emitted by mobile phones, on brain activity. Ten women and ten men, matched for age and educational level, performed a short memory task (Wechsler test), with simultaneous Electroencephalogram (EEG) recordings at 15 scalp electrodes, both without (baseline) and with exposure to an 1,800 MHz signal. The EEG energy was found concentrated at the four basic EEG bands [α (8–13 Hz), β (14–30 Hz), δ (0–4 Hz), and θ (5–7 Hz)]. The analysis revealed that in the presence of EMF, the energy of the β band was significantly greater for females than for males at the majority of the electrodes. Since beta oscillation is associated with the shift of attention during the perception, these findings may indicate that the particular EMF (1,800 MHz signal) exerts an influence on this brain activity, which appears to be gender-related.  相似文献   

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A strong increase in the demand for some commodities over the last decade will have a major impact on their future supply situation. Of increasing importance, therefore, is an assessment of a commodity's criticality, and especially its supply risk, by appropriate indicators. The literature has proposed numerous indicators of the supply risk. Here, we use the convenience yield of commodity futures as a supply risk indicator to address some of the major shortcomings of existing indicators, especially regarding their predictive power. This paper aims to test the applicability of the convenience yield as an indicator of a commodity's future supply risk. Therefore, we calculate historical convenience yields for 3-, 15-, and 27-month futures contracts for five major industrial metals (aluminum, copper, lead, nickel, and zinc) during the period 1999 to 2011. We compare the convenience yields at the beginning of the contract period to known indicators at maturity to find that the convenience yield has generally predictive power for the static stock lifetime (i.e., inventory volume/turnover) and future spot prices. Furthermore, we find that, with some restrictions, the convenience yield is an applicable indicator of a commodity's supply risk.  相似文献   

4.
The Ozegahara peatland, in the Nikko-Oze National Park in Japan, is ecologically significant because of its oligotrophic environment; it is one of the most strictly preserved areas in the country. The isotope ratio of nitrogen (15N/14N) and carbon (13C/12C) and C/N ratio of peat moss (Sphagnum spp.) and sundew (Drosera rotundifolia) in the peatland were analyzed. The correlation of the isotope ratio with some parameters (sundew population density, number of trapped insects, water level, bog myrtle coverage, and visitor density) was investigated. The nitrogen isotope ratio of sundew showed the most significant covariation with visitor density, where sundew from lunch areas or along busy walkways showed a higher nitrogen isotope ratio. The nitrogen isotope ratio of peat moss covaried, not only with route traffic frequency but also with water level, bog myrtle coverage, and number of trapped insects by sundew, indicating that factors other than the visitor level influence the local nitrogen cycle. This study suggests that the nitrogen imported into the peatland by visitors is a principal factor to be monitored for the maintenance of the natural environment.  相似文献   

5.
The restoration of ecosystem services, i.e., production, regulation, and information, is a global challenge, which the federal state of Mecklenburg-Vorpommern in NE Germany addressed in 2000 by rewetting over 20,000 ha of degraded peatlands within the Mire Restoration Program. We evaluated ecosystem services in 23 rewetted sites by assessing the following mire parameters within a ten year period: (a) dominant vegetation at the ecosystem level, (b) peat formation potential at the landscape level, and (c) aboveground biomass and nutrient levels. Seven to 10 years after rewetting, the wetlands formed a mosaic of vegetation types with the highest potential for peat formation and several dominant, peat-forming species accumulated high levels of aboveground biomass and nutrients (C, N, P). Common reed (Phragmites australis) accumulated the most biomass (up to 24 t dry matter/ha), and N+P during the growing season. A future management option is to annually harvest aquatic and wetland plants to reduce nutrient levels in restored mire ecosystems.  相似文献   

6.
Although agriculture in Australia is very productive, the current food supply systems in Australia fail to deliver healthy diets to all Australians and fail to protect the natural resources on which they depend. The operation of the food systems creates ‘collateral damage’ to the natural environment including biodiversity loss. In coming decades, Australia’s food supply systems will be increasingly challenged by resource price inflation and climate change. Australia exports more than half of its current agricultural production. Government and business are aiming to substantially increase production to bolster exports. This will increase pressure on agricultural resources and exacerbate ‘collateral’ damage to the environment. The Australian public have a deep and ongoing interest in a very wide range of issues associated with the food systems including the environment, health and sustainability. Food is something we require in order to live and a good diet is something we have to have to be healthy. For health over a life-time we need food security. However, we also require a range of other material goods and social arrangements in order to develop and flourish as human beings. And we need these other things to be secure over a life-time. Food is therefore one security among a range of other securities we need in order to flourish. The paper outlines a number of approaches, as examples, that help to identify what these other goods and arrangements might be. The approaches mentioned in this paper include human rights, national securities, human needs, authentic happiness, capabilities, sustainability and environmental ethics. The different approaches provide a way of evaluating the current situation and indicating a direction for change within the food systems that will address the problems. However, changing large systems such as those involved in food supply is difficult because inertias and vested interests make the current food supply systems resilient to change. The paper suggests that one of the first and ongoing tasks is to develop an understanding of the situation from a comprehensive social–ecological systems perspective. The paper also suggests that a practical leverage point for system change is restructuring the flow of information on the health, natural resources and biodiversity loss issues related to the food supply systems.  相似文献   

7.
The performance characteristics of a solar air heater can effectively be improved by providing artificial roughness in the form of protrusions and dimples of various shapes, sizes, and orientations on the underside of heated surface. An extensive literature review on artificial roughness elements has been carried and the correlations developed for heat transfer and friction factor for roughened solar air collector have been discussed and presented in this paper. The performance parameter has also been computed and compared with various kinds and shapes of roughness geometries using correlations developed by various investigators. The optimum values of the roughness parameters obtained by several investigators have also been discussed.  相似文献   

8.
This study explores different socio-economic and institutional factors influencing the adoption of improved soil conservation technology (ISCT) on Bari land (Rainfed outward sloping terraces) in the Middle Mountain region of Central Nepal. Structured questionnaire survey and focus group discussion methods were applied to collect the necessary information from farm households. The logistic regression model predicted seven factors influencing the adoption of improved soil conservation technology in the study area including years of schooling of the household head, caste of the respondent, land holding size of the Bari land, cash crop vegetable farming, family member occupation in off farm sector, membership of the Conservation and Development Groups, and use of credit. The study showed that technology dissemination through multi-sectoral type community based local groups is a good option to enhance the adoption of improved soil conservation technology in the Middle Mountain farming systems in Nepal. Planners and policy makers should formulate appropriate policies and programs considering the farmers' interest, capacity, and limitation in promoting improved soil conservation technology for greater acceptance and adoption by the farmers.  相似文献   

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This study analysed 14 management plans and guidelines from a 25-year period to understand trends in conservation planning. A Rosetta Stone Analysis was used for the systematic comparison of plans and guidelines. Management plans incorporated management philosophies, management scenarios, opportunities for infrastructure, and plans for data collection by 2000. As of 2010, they incorporated ecosystem services, stakeholders’ objectives and methods for storing and analysing data. The results demonstrate the complex nature of management plans, with an important workload for site managers. Recommendations for future planning include adjustments in planning timeframes and a better identification of conservation targets from initial stages.  相似文献   

11.
The siting of waste incinerators is often a highly contentious issue. Although most studies have focused on Western countries, municipal solid waste management has become an extremely pressing issue in China. Incineration is being strongly promoted by government officials, yet this has resulted in strong societal opposition. Through documentary analysis and in-depth stakeholder interviews, this article analyses three anti-incineration campaigns in Beijing, focusing on outcomes and campaigner strategies. Anti-incineration campaigns have partly undermined the government's top-down, non-consultative approach to waste management. In developing an ‘expert strategy’, campaigners have exploited government weakness whilst depoliticizing the issue. Yet rather than lead to a more open and consultative incineration policy, it is more likely that officials will circumvent unrest through increasing opacity and by choosing sites in locations where opposition is less likely to emerge.  相似文献   

12.
Over the past two decades, communication on environmental values, actions and performance has become an essential activity of organisations, because of the increased public concern and legislation related to the environment.

Stakeholders put pressure on companies to take environmental responsibility. In this framework, an effective environmental communication can generate value-added on companies' environmental work, and consequently, their competitiveness and profitability can benefit from communicating their environmental responsibility.

In 2006, the International Organization for Standardization (ISO) launched a standard for environmental communication, ISO 14063. ISO 14063 should not be used for third-party certification purposes. Instead, it is intended to be used as a guideline and support companies to ensure successful environmental communication. The aim of this paper is to prompt a discussion about the applicability of the standard ISO 14063 not only to single organisations but as a tool to plan the environmental communication strategy of a whole territorial area. This is achieved by performing a case study relating to the Interreg IVC-funded project “Progresland”. The project involved three Italian and one Spanish natural areas and demonstrated that ISO 14063 could be a valid support to define and implement an environmental communication plan for a territorial area.  相似文献   

13.
This study designs and applies a new energy-conservation type solar-powered lighting system using a high-pressure sodium lamp to areas not having any utility company's electricity. The proposed system uses a zero-voltage-switching (ZVS) DC/DC converter in the batteries’ charge circuit to reduce the switching loss for a higher charging efficiency. Said system also adopts the maximum power point tracking (MPPT) technique to maximize the solar panels’ photovoltaic conversion capability. When dark, the batteries in the proposed system will discharge, with a raised voltage, through a push-pull DC/DC converter; said voltage, as the input voltage of the series-parallel resonant inverter, will be regulated to dim the lamp. To enable the efficient usage of the batteries’ stored energy capacity, this control scheme of the proposed system may adjust the night-time discharge time lengths, according to season difference, and compute the usable capacity for the load, according to the batteries’ charged voltage, so as to select a suitable pre-scheduled light-dimming curve for the lamp to achieve energy conservation for the batteries and continuity in lighting when dark.  相似文献   

14.
Thirty-five soil samples were taken from unconfined mine waste, stream sediments, and surfaces unoccupied by mining and presumably unaffected by it, in a sulphur-mining zone surrounded by carbonate material and characterized by a semi-arid climate with short torrential storms. These samples were analysed and the results compared to estimate the spread of pollution in the landscape and to assess potential environmental risk. The mean concentrations of S, Zn, Cd, Pb, and As in mine waste were between 3.5-fold (As) and 50-fold (S) greater than unaffected soils. Oxidation of S led to a sharp drop in pH, strong weathering of minerals, and solubilisation of the constituent elements, forming a toxic acidic mine drainage with highly concentrated pollutants that were discharged into the drainage channels. Successive acid mine drainage into the soil on the valley floor spreads acidification and pollution downstream. The high carbonate content in surrounding soils played an important role in the increase of the pH and precipitation of S, Pb, and Al of the affected soils. Meanwhile, high mobility of Zn, Cd and As under basic conditions and a low Fe concentration explain the broad spread of these elements, as high concentrations were detected in soil more than 2000 m from the source. Only the soil solutions from near the waste dump (first 500 m) were highly phytotoxic, and moderately phytotoxic from 500 to 1500 m away. The concentration of pollutants in the leachates was clearly higher than in soil solutions, even in the soils located over 2000 m from the source, implying that the size of the polluted area will increase with time.  相似文献   

15.
ABSTRACT

In 2009 the Desertec Industrial Initiative (DII) was founded by several, predominant German enterprises. The objective of DII was to organise the conditions for the realisation of the Desertec idea, which aimed to both (a) supply Europe, in a large-scale manner, with electricity produced in solar power plants in North Africa and the Arabic peninsula and (b) contribute to the self-supply of the Middle East North Africa region (MENA). Protagonists of the desert energy idea saw this megatechnic project as a starting point for a new trans-Mediterranean EU-MENA union, critics in contrast as a neo-colonial project. Disputes over the adequate interpretation and implementation of the Desertec idea broke out from the beginning. In 2014/2015, the media talked of the failure of DII and of the Desertec concept. The majority of the members left DII at the end of 2014. On the other hand, in some MENA countries renewables are playing a crucial role in securing the future of the energy sector. This paper analyses the development of DII and the Desertec idea by using concepts from Social Studies in Technology, and especially by the multi-level perspective approach in Transition Studies. It shows how the interplay of different factors, such as technological developments, entrepreneurial performances and political processes, lead to internal conflicts and the non-realisation – up to now – of related large-scale energy projects. As an important aspect of the paper, different understandings of the future of our energy supply and of North–South relations are presented in detail.  相似文献   

16.
This paper presents the idea of a decision-support system for a livestock farm, called “ethical accounting”, to be used as an extension of traditional cost accounting. “Ethical accounting” seeks to make available to the farmer information about how his decisions affect the interests of farm animals, consumers and future generations. Furthermore, “ethical accounting” involves value-based planning. Thus, the farmer should base his choice of production plan on reflections as to his fundamental objectives, and he should make his final decision only after having seriously considered the various consequences for the affected parties. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
Abstract

The popularity of sustainability indicators is almost inescapable. From the early pioneers such as the ‘Sustainable Seattle’ project (Atkisson, ‘Developing Indicators of a Sustainable Community: lessons from Sustainable Seattle’, in: D. Satterthwaite (Ed), The Earthscan Reader in Sustainable Cities, London, Earthscan, 1996) to the comprehensive European Union benchmarking launched in 2003 (European Commission, European Common Indicators: towards a local sustainability profile, Milan, Ambiente Italia, 2003), it seems that consensus has been reached about the positive impacts that establishing sustainability indicators can bring. This paper uses the case of developing sustainability indicators on the Island of Guernsey over the last three years to show that Agenda 21's call to activate grassroots action is being realised, but in ways that are neither top-down and modernist in approach nor bottom-up and postmodernist as Agenda 21 advocates. Although best practice literature often suggests that community involvement must be engaged prior to designing sustainability indicators, this paper explores the reasons why this is not always possible. Guernsey's case is used to show how it only became possible to generate interest in the indicator process once they were actually up and running. However, it also shows that once interest was secured by a few relevant stakeholders it became possible to further evolve the indicators in a process that has slowly been attracting more and more of the Island's community.  相似文献   

18.
This review presents first ever literature survey on historical development of farm animal welfare indicators and assessment in the Danube region. This area, encompassing European Eastern countries and the Balkans, is to a large extent heterogeneous in terms of culture and language. However, international (English) publications were disproportionally small compared to the amount of research institutions and animal welfare activities present in the region. Therefore, the authors aimed at investigating the published literature, focusing on country level and on native languages. Data were collected for the 1980–2015 period referring to scientific papers published in international and national journals, papers and abstracts in proceedings of the international and national conferences, reviews, monographs, short communications, Ph.D., Master and Graduation theses. Welfare assessment of all farm animal species was observed including fish. Over 180 papers were in line with the preselected index. Data collected showed that publishing dynamics grew rapidly towards the last decade. Most of the studies were focused on animal welfare indicators such as stress, injuries and mutilations, behaviour, body condition and management practices. Cattle, chickens, pigs and sheep were the predominant species investigated. The study revealed that experts from the region were greatly involved in the studies of animal welfare indicators and assessment, contributing to development of the currently most widely used animal welfare assessment protocols, thus having an important role in animal welfare research and protection.  相似文献   

19.
Managing municipal solid waste is a pressing environmental and political concern for Canadian municipalities who bear the primary responsibility for waste management (WM). In 2015, Metro Vancouver’s (MV’s) plans to expand their capacity to expand their WM capacity with energy-from-waste technology was abandoned, despite shrinking landfill space and persistent public opposition to new landfills. Using Bulkeley et al.’s [(2005). Governing municipal waste: towards a new analytical framework. Journal of Environmental Policy and Planning, 7(1), 1–23. doi:10.1080/15239080500251700] ‘modes of governing framework’, we analyse MV’s failed attempt to expand their energy-from-waste capacity to better understand the challenges associated with governing WM in Canada. We argue that a history of downloading responsibility for WM to municipalities, regional districts, and industry has fragmented WM governance, posing a challenge for developing new waste infrastructure. We find that this localization of responsibility is incompatible with contemporary WM challenges. The scalar mismatch between waste’s material impacts and the scale at which waste is managed has resulted in co-dependence and conflict between putatively independent municipalities, regional districts, and private companies. This inhibits higher-level WM coordination while the autonomy of individual municipalities is simultaneously undermined.  相似文献   

20.
The Brambell Report of 1965 recommended that animals should have the freedom to stand up, lie down, turn around, groom themselves and stretch their limbs. The Farm Animal Welfare Council (FAWC) developed these into the Five Freedoms, which are a framework for the analysis of animal welfare. The Five Freedoms are well known in farming, policy making and academic circles. They form the basis of much animal welfare legislation, codes of recommendations and farm animal welfare accreditation schemes, and are the foundation of the Welfare Quality® assessment scheme. The Five Freedoms are also extensively employed for the education of veterinary and animal welfare science students. Hence they have proven to be of great practical utility. In this paper, the Five Freedoms framework is examined in terms of necessary and sufficient conditions for the analysis of animal welfare. Overall, the Five Freedoms are judged to be individually necessary and jointly sufficient as a framework for the analysis of animal welfare. FAWC has recently criticized the Five Freedoms for concentrating on negative aspects of welfare. However, it is shown here how the satisfaction of the Five Freedoms should lead to good welfare, from the animal’s point of view. The Five Freedoms are formulated as ideals of animal welfare. This has significant advantages that have likely contributed to their impact. However, the ideality of the Five Freedoms means that the framework is without power to determine what a satisfactory level of animal welfare is, in an ethical sense.  相似文献   

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