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991.
Marko S. Markov 《The Environmentalist》2007,27(4):457-463
The interest toward clinical application of magnetic and electromagnetic stimulation increases worldwide. Numerous publications
discussed the possibility exogenous magnetic and electromagnetic fields to initiate effects on various biological processes,
which are of critical importance for healing of different injuries and pathologies. Today, magnetic and electromagnetic fields
are increasingly utilized for treatment of various musculoskeletal injuries and pathologies. For musculoskeletal injuries
and post-surgical, post traumatic and chronic wounds, reduction of edema is a major therapeutic factor in the acceleration
of pain and stress relief, and thus contribute to healing processes. Electromagnetic and magnetic fields appear to be unique
in their safety during clinical use. The application of this new modality will be facilitated by searching for biophysical
mechanisms of action as well as by establishing exact dosimetry of application. In that respect basic science research needs
to be developed in parallel with clinical applications. Magnetotherapy provides a non-invasive, safe, and easy method to directly
treat the site of injury, the source of pain and inflammation, and other types of injury. Unfortunately, there are many obstacles
that magnetotherapy has to overcome—both from the mainstream medicine as well as from the manufacturers and distributors of
magnetic devices. The physical principle of magnetism as well as the physiological bases for the use of magnetic field for
tissue repair are subjects of this review. 相似文献
992.
MIRIAM MIRANDA CAREL DIEPERINK PIETER GLASBERGEN 《Environment, Development and Sustainability》2007,9(1):1-19
This article analyses the application of voluntary environmental agreements (VEAs) in watershed protection in Costa Rica.
Next to an involvement of private energy firms, the Costa Rican state, and farmers, the participation of NGOs is a remarkable
feature. From an analysis of these multi-stakeholder arrangements, it is concluded that these arrangements bring benefits
to all actors involved. VEAs have been able to grow as powerful policy instruments, generating positive environmental effects.
Essential is their embedded ness in a broader set of environmental policies, especially related to forest management
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
993.
We documented valley and channel characteristics and wood loads in 19 reaches of forested headwater mountain streams in the
Bighorn National Forest of northern Wyoming. Ten of these reaches were in the Upper Tongue River watershed, which has a history
of management including timber harvest, tie floating, and road construction. Nine reaches were in the North Rock Creek watershed,
which has little history of management activities. We used these data to test hypotheses that (i) valley geometry correlates
with wood load, (ii) stream gradient correlates with wood load, and (iii) wood loads are significantly lower in managed watersheds
than in otherwise similar unmanaged watersheds. Statistical analyses of the data support the first and third hypotheses. Stream
reaches with steeper valley side slopes tend to have higher wood loads, and reaches in managed watersheds tend to have lower
wood loads than reaches in unmanaged watersheds. Results do not support the second hypothesis. Shear stress correlated more
strongly with wood load than did stream gradient, but statistical models with valley-scale variables had greater explanatory
power than statistical models with channel-scale variables. Wood loads in stream reaches within managed watersheds in the
Bighorn National Forest tend to be two to three times lower than wood loads in unmanaged watersheds. 相似文献
994.
The zebrafish embryo model in environmental risk assessment—applications beyond acute toxicity testing 总被引:4,自引:3,他引:1
Scholz S Fischer S Gündel U Küster E Luckenbach T Voelker D 《Environmental science and pollution research international》2008,15(5):394-404
BACKGROUND, AIM, AND SCOPE: The use of fish embryos is not regulated by current legislations on animal welfare and is therefore considered as a refinement, if not replacement of animal experiments. Fish embryos represent an attractive model for environmental risk assessment of chemicals since they offer the possibility to perform small-scale, high-throughput analyses. MAIN FEATURES: Beyond their application for determining the acute toxicity, fish embryos are also excellent models for studies aimed at the understanding of toxic mechanisms and the indication of possible adverse and long-term effects. Therefore, we have reviewed the scientific literature in order to indicate alternative applications of the fish embryo model with focus on embryos of the zebrafish. RESULTS AND DISCUSSIONS: The analysis of the mode of action is important for the risk assessment of environmental chemicals and can assist in indicating adverse and long-term effects. Toxicogenomics present a promising approach to unravel the potential mechanisms. Therefore, we present examples of the use of zebrafish embryos to study the effect of chemicals on gene and protein patterns, and the potential implications of differential expression for toxicity. The possible application of other methods, such as kinase arrays or metabolomic profiling, is also highlighted. Furthermore, we show examples of toxicokinetic studies (bioconcentration, ABC transporters) and discuss limitations that might be caused by the potential barrier function of the chorion. Finally, we demonstrate that biomarkers of endocrine disruption, immune modulation, genotoxicity or chronic toxicity could be used as indicators or predictors of sub-acute and long-term effects. CONCLUSIONS: The zebrafish embryo represents a model with an impressive range of possible applications in environmental sciences. Particularly, the adaptation of molecular, system-wide approaches from biomedical research is likely to extend its use in ecotoxicology. RECOMMENDATIONS AND PERSPECTIVES: Challenges for future research are (1) the identification of further suitable molecular markers as indicators of the mode of action, (2) the establishment of strong links between (molecular) effects in short-term assays in embryos and long-term (toxic) effects on individuals, (3) the definition of limitations of the model and (4) the development of tests that can be used for regulatory purposes. 相似文献
995.
Crowding and Experience-Use History: A Study of the Moderating Effect of Place Attachment Among Water-Based Recreationists 总被引:1,自引:1,他引:0
Effective recreation resource management relies on understanding visitor perceptions and behaviors. Given current and increasing
pressures on water resources, understanding crowding evaluations seems important. Beyond crowding, however, variables that
possibly relate to or influence crowding are of interest and in particular, place attachment and experience-use history (EUH).
As EUH is related to place attachment and likely affects crowding, this study explored the moderating effect of place attachment
dimensions on the relationships between EUH and visitor crowding evaluations. Water based recreationists at a U.S. Army Corps
of Engineers site were contacted onsite and asked questions related to experience-use history, crowding evaluations, place
attachment, and activity participation. Anglers and campers at the site identified similar crowding perceptions and place
attachments. Only one of eight models tested revealed a moderating effect. Specifically, place identity moderated the relationship
between the total times visited in the past twelve months and expected crowding among anglers. As such, the quest continues
to understand the relationship among these important variables. 相似文献
996.
Ramiz M. Mamedov Boyukagha N. Mustafayev 《Environment, Development and Sustainability》2007,9(2):131-142
In order to determine the potential for sustainable regional development of the Caspian coastal zone, a study was made for
the Khachmaz–Absheron zone of Azerbaijan. An evaluation was performed to assess the anthropogenic load on landscapes. Using
the 8-point scale offered by Isachenko [2001, Ecological Geography of Russia, Saint Petersburg University Press, Saint Petersburg]
for the indicators of agricultural, industrial, urban and integral anthropogenic loads, we did a preliminary ranking of the
provinces in the Khachmaz–Absheron zone of Azerbaijan for the each indicator taken separately. Vital statistics were used
as a supplementary indicator of environmental conditions in the region. By comparing the data for provinces with each other
and the data on Azerbaijan average, we have classified the provinces into 4 groups according to specific combinations of the
indicators. Each group of provinces has distinctive environmental conditions and features for sustainable development. The
classification makes it possible to develop certain recommendations for the regional sustainable development. Measures to
be implemented within the Azerbaijan State Program on Social and Economic Development of Regions are also discussed. In the
Khachmaz province, production of ecologically pure products is highly recommended. Special attention should be given to the
development of tourism and recreational institutions in the Khachmaz, Khizi and Devechi provinces. Recommendations for these
provinces include further development of industry on the basis of modern safe technologies. The irrigation and drainage networks
should be reconstructed. The reconstruction will make it possible to reduce water loss and to increase the productivity of
agriculture. In the Absheron province, Baku and Sumgait cities environmental systems are overloaded, and so the works at highly
polluting enterprises must be stopped, the enterprises have to be re-equipped (old filters must be changed first of all) or
relocated from the area (a decrease of environmental risk should be in the focus of attention). For improving of air quality,
green areas should increase. There is a need to reduce urban traffic density and to reconstruct highways. Use of old vehicles
must be forbidden or restricted, and transition to environmentally friendly fuel should be supported in every way possible.
It is necessary to bring the waste management system and sanitary landfills up to international standards, and to improve
the water supply and sewerage systems. 相似文献
997.
Thacker NP Nitnaware VC Das SK Devotta S 《Environmental science and pollution research international》2007,14(4):225-226
Samples of effluents, sludge, pulp, final products (paper) and soil were collected from the identified pulp and paper mills
in India. The samples were analysed for 2,3,7,8-tetrachloro-dibenzo-p-dioxin (2,3,7,8-TCDD) and other dioxin congeners and
precursors. Pulp and paper mills using chlorine for the bleaching process showed the presence of 2,3,7,8-TCDD in effluent
samples. In the effluent and pulp samples from mills where chlorine dioxide was used as a bleaching agent, the 2,3,7,8-TCDD
congener ranged from below the detection limit 0.05 to 0.12 ngL−1/ngg−1. The relative standard deviation of reproducibility and the percent recovery of 2,3,7,8-TCDD were 2.07 and 82.4% in pulp
and 2.8 and 92% in effluent, respectively. The 1,3,6,8-TCDD was the only other major dioxin congener found in the treated
and untreated effluent and sludge samples. However, dichlorobenzene, trichlorophenyl, and hexachlorobiphenyl were detected
in all samples. The formation of dioxins can be minimised by replacing chlorine with chlorine dioxide in bleaching processes
in pulp and paper mills. 相似文献
998.
Berghahn R Mohr S Feibicke M Meinecke S Sperfeld E 《Environmental science and pollution research international》2007,14(3):190-193
Goal, Scope and Background One of the advantages of long-term mesocosm experiments as compared to short-term standard toxicity tests in the laboratory
is the potential for detecting secondary effects due to the interaction of species and recovery with biomass of macrophytes
being an important endpoint. However, generating biomass data by harvesting is often laborious, time-consuming, costly and
restricted to the end of the experiment. Moreover, valuable information may get lost, in particular in single application
studies, since maximal primary effects and secondary effects or recovery occur per se at different times. Potamogeton natans was used as an example in order to test whether number and area of floating leaves can be reliably measured and be used as
intermediate and final endpoints in mesocosm effect studies.
Methods Digital photos, which were taken of the water surface in the course of an indoor pond mesocosm study on herbicide effects,
were subjected to image analysis. The results were compared to wet weight and ash-free dry weight of Potamogeton at the end of the herbicide study.
Results and Discussion Both number and area of floating leaves indicated the same herbicide effects as wet weight and ash-free dry weight of Potamogeton. Error introduced by the different work steps is small and can be further minimised by a number of method improvements.
Recommendations and Perspectives In indoor mesocosm studies, errors due to the perspective adjustment may be circumvented by taking the photos perpendicular
to the water surface. Correction for lens aberration, identical light conditions and the use of fluorescence images are considered
promising. Field applications are proposed. 相似文献
999.
Francesca Porri Gerardo I. Zardi Christopher D. McQuaid Sarah Radloff 《Marine Biology》2007,152(3):631-637
Settlement is a major determinant of intertidal populations. However, the energy costs of lost larvae are very high. Accordingly,
arrival and attachment on suitable substrata are essential requirements for species’ survival. On the intertidal, the presence
of cues left by adult or juvenile conspecifics could be vital for the successful establishment of larvae arriving on the shore.
Two mussel species, the indigenous Perna perna and the invasive Mytilus galloprovincialis, co-occur on the lower eulittoral zone on the south coast of South Africa. P.
perna dominates the low and M. galloprovincialis the high mussel zones, with co-existence in the mid mussel zone. This study tested the hypothesis of settlement selectivity
for conspecifics in these two mussel species, to understand whether the final adult distribution of mussels on the shores
is determined by active behavioural and chemical mechanisms. Preferential selection by larvae for conspecifics was tested
in the field during the peak settlement period in 2004 in natural mussel beds across zones and through manipulative experiments
in the mid-zone where the species co-exist. On natural beds, settlement was determined by counts of settlers attached over
48 h onto artificial collectors. Collectors were placed on beds of P. perna and M. galloprovincialis present at both high- and low-adult densities, as well as in mixed beds. On such natural beds, settlers of both species consistently
favored low-zone P. perna beds. Settlement patterns over 24 h onto experimentally created mussel patches consisting of P.
perna, M. galloprovincialis or the two species combined beds, set in the mixed zone, did not conform with the results of the natural beds study: settlers
of both species settled with no discrimination among different patches. The results indicate that mussels, which are sedentary,
lack attraction to conspecifics at settlement. This highlights the importance of tidal height in setting settlement rates,
and of post-settlement events in shaping populations of these broadcast spawners. 相似文献
1000.
Flexible and robust strategies for waste management in Sweden 总被引:1,自引:0,他引:1
Finnveden G Björklund A Reich MC Eriksson O Sörbom A 《Waste management (New York, N.Y.)》2007,27(8):S1-S8
Treatment of solid waste continues to be on the political agenda. Waste disposal issues are often viewed from an environmental perspective, but economic and social aspects also need to be considered when deciding on waste strategies and policy instruments. The aim of this paper is to suggest flexible and robust strategies for waste management in Sweden, and to discuss different policy instruments. Emphasis is on environmental aspects, but social and economic aspects are also considered. The results show that most waste treatment methods have a role to play in a robust and flexible integrated waste management system, and that the waste hierarchy is valid as a rule of thumb from an environmental perspective. A review of social aspects shows that there is a general willingness among people to source separate wastes. A package of policy instruments can include landfill tax, an incineration tax which is differentiated with respect to the content of fossil fuels and a weight based incineration tax, as well as support to the use of biogas and recycled materials. 相似文献