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31.
The study and observation of electromagnetic phenomena have followed the evolution of human thought from the dawn of civilization to the present day; also magnetotherapy has followed a similar path. Magnetotherapy has been applied and continues to be applied in many branches and fields of medicine, as it accelerates the healing of fractures, has analgesic and anti-inflammatory properties that can help in inflammatory or degenerative diseases of bones, joints and the peripheral nervous system, and stimulates the healing of open skin lesions (such as bed sores, diabetic ulcers) etc. If magnetotherapy has so many fields of application in medicine, we may therefore ask why doubts, prejudice and limitations to its therapeutic use still exist. This brief historical excursion wants to give a small contribution to answer the question.  相似文献   
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In this paper we propose a decision support system that can provide information on the environmental impact of anthropic activities by examining their effects on groundwater quality. We use the combined value of both intrinsic vulnerability of a specific local aquifer, obtained by implementing a parametric managerial model (SINTACS), and a degree of hazard value, which takes into account specific human activities. Incomplete information is notoriously common in environmental planning. To overcome this deficiency we apply an algorithmic and a qualitative approach, based on expert judgment incorporated into the system's knowledge base. The decision support system takes into account the uncertainty of the environmental domain by using fuzzy logic and evaluates the reliability of the results according to information availability.  相似文献   
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The wasps of the genus Polistes (paper wasps), have a worldwide distribution and are widespread in human-built areas. Like other social wasps, they are at the top of food chains and are therefore exposed to the dangers of biomagnification, given that the larvae are fed predominantly with prey that consist of herbivorous insects. The larval faeces, larval fecal masses, in the form of a semi-solid ball, are made up of the residues of the diet of the larva, which are emitted and compressed on the floor of the cell during the larval metamorphosis. Larval fecal masses may accumulate lead (up to 36 times with respect to the adult body), therefore they were used as substrate for the analysis. From the analysis of sample nests of Polistes dominulus in various sites of the urban area of Florence, it emerges that the larval fecal masses are an analytical substrate with which it is possible to distinguish zones with differing degrees of lead pollution. The lead concentration measured in the larval fecal masses turns out to be directly correlated with vehicle traffic density, the main lead source in Florence when the survey was carried out. The notable increase in the lead concentration of larval fecal masses from the rural to the urban nest (11.15 times), in contrast with the much more limited level of pupae (4.39 times), seems to indicate the efficiency of the excretion and/or barrier mechanisms. These wasps seem to be a promising species for biomonitoring lead pollution in order to better understand its dynamics in anthropic ecosystems after the progressive diffusion of unleaded gasoline.  相似文献   
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Habitat corridors are important tools for maintaining connectivity in increasingly fragmented landscapes, but generally they have been considered in single‐species approaches. Corridors intended to facilitate the movement of multiple species could increase persistence of entire communities, but at the likely cost of being less efficient for any given species than a corridor intended specifically for that species. There have been few tests of the trade‐offs between single‐ and multispecies corridor approaches. We assessed single‐species and multispecies habitat corridors for 5 threatened mammal species in tropical forests of Borneo. We generated maps of the cost of movement across the landscape for each species based on the species’ local abundance as estimated through hierarchical modeling of camera‐trap data with biophysical and anthropogenic covariates. Elevation influenced local abundance of banded civets (Hemigalus derbyanus) and sun bears (Helarctos malayanus). Increased road density was associated with lower local abundance of Sunda clouded leopards (Neofelis diardi) and higher local abundance of sambar deer (Rusa unicolor). Pig‐tailed macaque (Macaca nemestrina) local abundance was lower in recently logged areas. An all‐species‐combined connectivity scenario with least‐cost paths and 1 km buffers generated total movement costs that were 27% and 23% higher for banded civets and clouded leopards, respectively, than the connectivity scenarios for those species individually. A carnivore multispecies connectivity scenario, however, increased movement cost by 2% for banded civets and clouded leopards. Likewise, an herbivore multispecies scenario provided more effective connectivity than the all‐species‐combined scenario for sambar and macaques. We suggest that multispecies habitat connectivity plans be tailored to groups of ecologically similar, disturbance‐sensitive species to maximize their effectiveness. Evaluación de la Conectividad de Terrenos Multiespecie en una Comunidad Tropical de Mamíferos  相似文献   
35.
ABSTRACT: In this paper we seek to identify historical indicators of international freshwater conflict and cooperation and to create a framework to identify and evaluate international river basins at potential risk for future conflict. We derived biophysical, socioeco‐nomic, and geopolitical variables at multiple spatial and temporal scales from GIS datasets of international basins and associated countries, and we tested these variables against a database of historical incidents of international water related cooperation and conflict from 1948 to 1999. International relations over freshwater resources were overwhelmingly cooperative and covered a wide range of issues, including water quantity, water quality, joint management, and hydropower. Conflictive relations tended to center on quantity and infrastructure. No single indicator—including climate, water stress, government type, and dependence on water for agriculture or energy—explained conflict/cooperation over water. Even indicators showing a significant correlation with water conflict, such as high population density, low per capita GDP, and overall unfriendly international relations, explained only a small percentage of data variability. The most promising sets of indicators for water conflict were those associated with rapid or extreme physical or institutional change within a basin (e.g., large dams or internationalization of a basin) and the key role of institutional mechanisms, such as freshwater treaties, in mitigating such conflict.  相似文献   
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Numerous studies have demonstrated the utility of extremely low frequencies (ELF) electromagnetic fields in the treatment of pain. Moreover, the effects of these fields seems to depend on their respective codes. In our study we want to value the effects and the safety of the TAMMEF (Therapeutic Application of a Musically Modulated Electromagnetic Field) system, which field is piloted by a musical signal and its parameters are modified in time, randomly varying within the respective ranges, so that all possible codes can occur during a single application. Ninety subjects, affected by chronic low back pain, were enrolled in the study and randomly divided into three groups of 30 patients each: A exposed to TAMMEF, B exposed to ELF, C exposed to a simulated field. All subjects underwent a cycle of 15 daily sessions of 30 minutes each and a clinical examination upon enrolment, after 7 days of therapy, at the end of the cycle and at a follow-up 30 days later. All the patients of groups A and B completed the therapy without the appearance of side effects: they presented a significant improvement of the subjective pain and the functional limitation, which remained stable at the follow-up examination. In group C, there was no improvement of the pain symptoms or articular functionality. This study suggests that the TAMMEF system is efficacious and safe in the treatment of patients with chronic low back pain.  相似文献   
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