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1.

This article offers an economic analysis of the international and U.S. laws governing the recovery of archaeological data from historic shipwrecks. The framework combines values of treasure salvage and archaeological knowledge. It is suggested that U.S. salvage law, sometimes extended to international waters, gives insufficient protection to archaeological value, but that UNESCO's Convention on the Protection of the Underwater Cultural Heritage goes too far in the other direction. Two other legal regimes (government-salvager and interstate agreements) are shown to have the potential to maximize the social values of historic shipwrecks. It is also suggested that a move towards maximizing social values would be promoted if the U.S. admiralty courts tied the size of salvage awards more closely to the quality of the archaeological work performed.  相似文献   

2.
The objectives of this study are the determination of forest fire risks with the fuzzy analytic hierarchy process (FAHP) and the mapping of risk levels with the use of geographic information systems (GIS). Socioeconomic, topographic, climatic, and stand structures have been taken into consideration as instrumental criteria in terms of fire risk. Each risk criteria and their sub-criteria membership grades have been determined with the fuzzy set theory. Five-scale fuzzy linguistic importance has been used for pairwise comparison matrices. Criterion weights have been mapped with the use of GIS, and a final risk map was established with weighted overlay analysis. Socioeconomic properties had the highest impact on fire risk with 35%. The high risk degree of this criterion manifests in shrublands with substantial fuel loads and young Calabrian pine forests in low elevation areas at the edge of roads, urban and urban periphery areas, south sloping, and steep sloped areas. The lowest risk degree was manifest in stands of cedar, black pine, and juniper forests, qualifying as old growth spreading in sub-mountain areas where land usage is rather low. Experiences regarding high accuracy fire risk determination and decision support approaches for fire risk management have been discussed and concluded in terms of applied FAHP and GIS procedures.  相似文献   

3.
Dendrochronological methods have been widely used to determine the date of construction and provenance of shipwrecks. Despite a large number of shipwrecks, the application of dendroarchaeological techniques is relatively incipient in the coasts of South America. This paper presents the results of a dendroarchaeological study conducted at the shipwreck site "Bahía Galenses" (BG), located in the western sector of Golfo Nuevo, on the Patagonian coast of the South Atlantic Ocean. Based on previous archaeological research, two hypotheses were tested in this study. First, the wreck described in the BG 2 sub-site corresponds to a mid-19th-century whaler built in the northeastern US. Second, these remains correspond to the Dolphin, a northeastern American whaler built in Warren (Rhode Island) in 1850 and shipwrecked in the Atlantic coast of Patagonia in 1859. Using dendroarchaeological provenance methods and a novel approach based on the gridded North American Drought Atlas, we found highly significant correlations between the wreck's tree-ring width series and white oak and yellow pine tree-ring reference chronologies from the eastern US. The latest non-cutting dates obtained in this analysis correspond to the year 1849. To our knowledge, our study pioneered the use of dendrochronological methods for dating and establishing the provenance of a whaler's remains on the Atlantic coast of South America and encourages the feasibility for future dendroarchaeological research based on the large number of wooden shipwrecks that occurred in the region.  相似文献   

4.
Industrial ecology (IE) methodologies, such as input/output or material flow analysis and life cycle assessment (LCA), are often used for the environmental evaluation of circular economy strategies. Up to now, an approach that utilizes these methods in a systematic, integrated framework for a holistic assessment of a geographic region's sustainable circular economy potential has been lacking. The approach developed in this study (IE4CE approach) combines IE methodologies to determine the environmental impact mitigation potential of circular economy strategies for a defined geographic region. The approach foresees five steps. First, input/output analysis helps identify sectors with high environmental impacts. Second, a refined analysis is conducted using material flow and LCA. In step 3, circular strategies are used for scenario design and evaluated in step 4. In step 5, the assessment results are compiled and compared across sectors. The approach was applied to a case study of Switzerland, analyzing 8 sectors and more than 30 scenarios in depth. Carbon capture and storage (CCS) from waste incineration, biogas and cement production, food waste prevention in households, hospitality and production, and the increased recycling of plastics had the highest mitigation potential. Most of the scenarios do not influence each other. One exception is the CCS scenarios: waste avoidance scenarios decrease the reduction potential of CCS. A combination of scenarios from different sectors, including their impact on the CCS scenario potential, led to an environmental impact mitigation potential of 11.9 Mt CO2-eq for 2050, which equals 14% of Switzerland's current consumption-based impacts.  相似文献   

5.
In recent years, the number of biotech enterprises in Europe has grown spectacularly, largely fueled by the increasing number of entrepreneurial initiatives from Europe's leading research institutes. The place held on the economic market by these enterprises, is a question that market analysts have been asking themselves since their rapid growth and, more particularly, their over valuation which, at times, has led to the crash of their shares on the stock markets. To be sure, this article does not claim to go into an in-depth financial analysis to explain the details of certain "shipwrecks". Rather, it just would like to provide some useful indications for all those having embarked, or desirous of doing so, in the creation of biomedical enterprises.  相似文献   

6.
Slove J  Janz N 《PloS one》2011,6(1):e16057
The "oscillation hypothesis" has been proposed as a general explanation for the exceptional diversification of herbivorous insect species. The hypothesis states that speciation rates are elevated through repeated correlated changes--oscillations--in degree of host plant specificity and geographic range. The aim of this study is to test one of the predictions from the oscillation hypothesis: a positive correlation between diet breadth (number of host plants used) and geographic range size, using the globally distributed butterfly subfamily Nymphalinae. Data on diet breadth and global geographic range were collected for 182 Nymphalinae butterflies species and the size of the geographic range was measured using a GIS. We tested both diet breadth and geographic range size for phylogenetic signal to see if species are independent of each other with respect to these characters. As this test gave inconclusive results, data was analysed both using cross-species comparisons and taking phylogeny into account using generalised estimating equations as applied in the APE package in R. Irrespective of which method was used, we found a significant positive correlation between diet breadth and geographic range size. These results are consistent for two different measures of diet breadth and removal of outliers. We conclude that the global range sizes of Nymphalinae butterflies are correlated to diet breadth. That is, butterflies that feed on a large number of host plants tend to have larger geographic ranges than do butterflies that feed on fewer plants. These results lend support for an important step in the oscillation hypothesis of plant-driven diversification, in that it can provide the necessary fuel for future population fragmentation and speciation.  相似文献   

7.
8.
哈萨克斯坦位于欧亚大陆腹地, 地处丝绸之路经济带的重要位置。中国与哈萨克斯坦开展生物多样性保护合作, 有助于解决地区生态环境问题和推动“一带一路”倡议的顺利实施。目前国内尚缺乏对哈萨克斯坦生物多样性及其保护状况的了解。本文在文献的基础上通过定量和定性分析方法, 从地理环境特征、生物多样性状况、保护成效和需求等维度对哈萨克斯坦生物多样性及其保护的总体情况进行了分析。分析结果表明, 哈萨克斯坦的生物多样性丰富, 但也存在着较严重的丧失问题; 哈萨克斯坦政府重视生物多样性保护, 积极承担相关国际履约义务; 在保护管理方面实行多级管理体制, 并与社会经济发展需求相结合, 取得了一定成效。  相似文献   

9.
Bovine tuberculosis (bTB) is a common disease in cattle and wildlife, with an impact on animal and human health, and economic implications. Infected wild animals have been detected in some European countries, and bTB reservoirs in wildlife have been identified, potentially hindering the eradication of bTB from cattle populations. However, the surveillance of bTB in wildlife involves several practical difficulties and is not currently covered by EU legislation. We report here the first assessment of the sensitivity of the bTB surveillance system for free-ranging wildlife launched in France in 2011 (the Sylvatub system), based on scenario tree modelling. Three surveillance system components were identified: (i) passive scanning surveillance for hunted wild boar, red deer and roe deer, based on carcass examination, (ii) passive surveillance on animals found dead, moribund or with abnormal behaviour, for wild boar, red deer, roe deer and badger and (iii) active surveillance for wild boar and badger. The application of these three surveillance system components depends on the geographic risk of bTB infection in wildlife, which in turn depends on the prevalence of bTB in cattle. We estimated the effectiveness of the three components of the Sylvatub surveillance system quantitatively, for each species separately. Active surveillance and passive scanning surveillance by carcass examination were the approaches most likely to detect at least one infected animal in a population with a given design prevalence, regardless of the local risk level and species considered. The awareness of hunters, which depends on their training and the geographic risk, was found to affect surveillance sensitivity. The results obtained are relevant for hunters and veterinary authorities wishing to determine the actual efficacy of wildlife bTB surveillance as a function of geographic area and species, and could provide support for decision-making processes concerning the enhancement of surveillance strategies.  相似文献   

10.
The transportation of hazardous materials assumes a fundamental importance, especially in urban areas, in order to identify possible alternative routes and to choose the route with minimum risk. Therefore, considering minimization risk rather than minimization distance to prevent a potential danger being transformed into a real event is necessary. In this article , a geographic information system (GIS)–based solution approach is developed to quantify the factors on each link in the network that contribute to a possible route. Based on the origin and destination of each shipment, the risks associated with the routes that minimize (1) the transport distance, (2) the population exposure, (3) the probability of an incident, and (4) the emergency response are evaluated. Proposed risk models are applied to fuel-oil transportation problem between resource point and 78 gasoline stations through the road network of Gaziantep city center. Results show that the proposed framework can contribute to the thought processes of policy-makers and carriers when they evaluate possible routes in order to minimize damage for transporting fuel oil.  相似文献   

11.
Coastal wetlands are facing an increasingly high risk of degradation and loss due to a wide variety of human activities and natural processes. Human encroachment, including land reclamation, drainage, and introduction of invasive species, has direct negative effects on wetlands, mainly through changes in hydrology and vegetation. Additionally, accelerated sea level rise (SLR) can result in flooding of wetlands in low-lying coastal zones. In this study, we present a rapid risk assessment method for coastal wetland loss and degradation. The main stress factors, i.e., urban sprawl, agriculture, coastal erosion, and SLR, have been examined and quantified through remote sensing and geographic information system spatial analysis. A weighted factor-based linear model has been used to evaluate the spatial risk levels of wetland loss. The proposed methodology is applied to the low-lying coastal wetlands of Hangzhou Bay in Shanghai, China. The results show that the regions closer to the sea have relatively higher risk levels on the landward side of the coastline, but relatively low risk levels on the seaward side of the coastline. This work emphasizes the need to sustainably use and protect wetlands in order to reduce disaster risks and contribute to the improvement of human well-being.  相似文献   

12.
Spatio-temporal parameters like step length, step frequency and ground contact time are directly related to sprinting performance. There is still a lack of knowledge, however, on how these parameters interact.Recently, various algorithms for the automatic detection of step parameters during sprint running have been presented which have been based on data from motion capture systems, video cameras, opto-electronic systems or Inertial measurement units. However, all of these methods suffer from at least one of the following shortcomings: they are (a) not applicable for more than one sprinter simultaneously, (b) only capable of capturing a small volume or (c) do not provide accurate spatial parameters. To circumvent these issues, the radio-based local position measurement system RedFIR could be used to obtain spatio-temporal information during sprinting based on lightweight transmitters attached to the athletes. To assess and optimize the accuracy of these parameters 19 100 m sprints of twelve young elite athletes (age: 16.5 ± 2.3 years) were recorded by a radio-based tracking system and a opto-electronic reference instrument. Optimal filter parameters for the step detection algorithm were obtained based on RMSE differences between estimates and reference values on an unseen test set. Attaching a transmitter above the ankle showed the best results.Bland-Altman analysis yielded 95% limits of agreement of [−14.65 cm, 15.05 cm] for step length [−0.016 s, 0.016 s] for step time and [−0.020 s, 0.028 s] for ground contact time, respectively. RMS errors smaller than 2% for step length and step time show the applicability of radio-based tracking systems to provide spatio-temporal parameters. This creates new opportunities for performance analysis that can be applied for any running discipline taking place within a stadium. Since analysis for multiple athletes is available in real-time this allows immediate feedback to coaches, athletes and media.  相似文献   

13.
A variety of methods have been used to make evolutionary inferences based on the spatial distribution of biological data, including reconstructing population history and detection of the geographic pattern of natural selection. This article provides an examination of geostatistical analysis, a method used widely in geology but which has not often been applied in biological anthropology. Geostatistical analysis begins with the examination of a variogram, a plot showing the relationship between a biological distance measure and the geographic distance between data points and which provides information on the extent and pattern of spatial correlation. The results of variogram analysis are used for interpolating values of unknown data points in order to construct a contour map, a process known as kriging. The methods of geostatistical analysis and discussion of potential problems are applied to a large data set of anthropometric measures for 197 populations in Ireland. The geostatistical analysis reveals two major sources of spatial variation. One pattern, seen for overall body and craniofacial size, shows an east-west cline most likely reflecting the combined effects of past population dispersal and settlement. The second pattern is seen for craniofacial height and shows an isolation by distance pattern reflecting rapid spatial changes in the midlands region of Ireland, perhaps attributable to the genetic impact of the Vikings. The correspondence of these results with other analyses of these data and the additional insights generated from variogram analysis and kriging illustrate the potential utility of geostatistical analysis in biological anthropology.  相似文献   

14.
Since the 1970s, surgical procedures on platysma muscle, aiming to achieve better results in face lifting, became popular and turned out to be an important surgical step for the plastic surgeon. Many plastic surgeons have contributed to the topic throughout these years, as several articles on the subject have been published. Articles dealing with platysma muscle still bring great interest among plastic surgeons. My concern with platysma muscle began in the mid-1970s and since then has grown continuously. I have steadily been studying the importance of the platysma muscle in the surgeries for facial rejuvenation, involving its anatomy, the techniques proposed, the results obtained, the recommendations for the best surgical procedure for each patient, and the complications. My experience and studies regarding platysma muscle, and the contributions I have brought into this field, are thoroughly described and discussed in this article.  相似文献   

15.
Several analysis of the geographic variation of mortality rates in space have been proposed in the literature. Poisson models allowing the incorporation of random effects to model extra‐variability are widely used. The typical modelling approach uses normal random effects to accommodate local spatial autocorrelation. When spatial autocorrelation is absent but overdispersion persists, a discrete mixture model is an alternative approach. However, a technique for identifying regions which have significant high or low risk in any given area has not been developed yet when using the discrete mixture model. Taking into account the importance that this information provides to the epidemiologists to formulate hypothesis related to the potential risk factors affecting the population, different procedures for obtaining confidence intervals for relative risks are derived in this paper. These methods are the standard information‐based method and other four, all based on bootstrap techniques, namely the asymptotic‐bootstrap, the percentile‐bootstrap, the BC‐bootstrap and the modified information‐based method. All of them are compared empirically by their application to mortality data due to cardiovascular diseases in women from Navarra, Spain, during the period 1988–1994. In the small area example considered here, we find that the information‐based method is sensible at estimating standard errors of the component means in the discrete mixture model but it is not appropriate for providing standard errors of the estimated relative risks and hence, for constructing confidence intervals for the relative risk associated to each region. Therefore, the bootstrap‐based methods are recommended for this matter. More specifically, the BC method seems to provide better coverage probabilities in the case studied, according to a small scale simulation study that has been carried out using a scenario as encountered in the analysis of the real data.  相似文献   

16.
野生鸟类传染性疾病研究进展   总被引:1,自引:1,他引:0  
刘冬平  肖文发  陆军  张正旺 《生态学报》2011,31(22):6959-6966
由于具有独特的飞行能力和极强的地理扩散能力,鸟类活动为某些传染性疾病的快速传播和扩散带来了潜在风险.自20世纪以来,以禽霍乱、禽波特淋菌病、西尼罗河热、禽流感等为代表的鸟类疾病频繁暴发,导致为数众多的野生鸟类、家禽甚至人类死亡,给社会造成巨大的经济损失.因此,有关鸟类传染性疾病的研究已引起了国内外学者的广泛关注.从鸟类传染性疾病的生态学特征、疾病对鸟类与人类社会的影响、鸟类对疾病的传播、鸟类疾病的监测、预警和防控等方面对野生鸟类的传染性疾病研究进展进行了综述.不同疾病导致的鸟类死亡量、易感物种数量、暴发频率和地理扩散等特征差异显著.20世纪以来,疾病已成为全球生物多样性的七大威胁因子之一.疾病可能造成鸟类大量死亡,从而对鸟类种群,特别是濒危鸟类种群造成严重影响.其中,人畜共患病还会导致家禽家畜甚至人类的死亡,从而对社会产生严重的影响.野生鸟类作为多种疾病传播的媒介,其移动和迁徙可能会导致疾病的传播与扩散.开展全面的监测活动和建立疾病预警体系,对于疾病的防控具有重要意义.  相似文献   

17.
Quantifying survey completeness is a key step in designing and interpreting biodiversity assessments. To date this has only been examined either at a local scale through repetitive sampling, or across broader geographic areas through multiple survey sites. In this paper, we determine the completeness of sampling at both local and continental scales, of the phytophagous arthropod assemblage on the Neotropical shrub Parkinsonia aculeata (Leguminosae). We used survey gap analysis (SGA) to determine whether existing surveys adequately sampled the diversity of environments and geographic space covered by the plant. Within defined geographic regions, we determined survey completeness at a local scale with species accumulation curves. SGA identified the highest priority sites for future sampling in the Sonoran Desert and the Pacific Coast of South America. The arthropods sampled on P. aculeata differed significantly between seasons, highlighting the importance of including surveys throughout the year. At the local scale, surveys in most regions were estimated to have sampled <50 % of all species. Only the Mexican Gulf, following 84 samples including 902 individuals, had a reasonably complete sample of all species (more than 50 %). As in other studies, rare species will continue to be detected even after extensive surveying, and it is likely that close to 100 samples or 1,000 individuals will be needed to attain 50 % survey completeness in a region. However, if the objective is to document close “host-associations” then effort may be better directed at surveying ecologically distinct new areas rather than exhaustive sampling in existing ones. Methods such as SGA can direct such surveys, and in conjunction with species-richness estimates, can be used to assess the adequacy of existing surveys.  相似文献   

18.
This study evaluated the health risk due to air pollution in São Paulo State, Brazil, comparing Brazil's standards and the World Health Organization (WHO) air quality guidelines. New methodology was applied considering, as hazard parameters, the maximum average concentrations of SO2, NO2, O3, CO, and PM10 from 2007 to 2011. As exposure parameters, population density and location sensitivity were considered. A health risk index based on fuzzy logic was performed to integrate the selected parameters, giving the likelihood of reaching different risk levels. Data gathering and spatial representation of parameters and risk scores were performed by means of geographic information system (GIS). Highest values of risk were observed in the Metropolitan Area of São Paulo and near the cities of Cubatão and Piracicaba, associated to vehicular and industrial emissions and sugar cane burning. Discussions about the need to revise national air quality standards have intensified over the past years. Generally, indices used for air quality do not consider the population exposed. This study showed the integration of GIS with fuzzy logic methodology to be a useful tool for health risk assessment. When evaluating the risk, exposure parameters must be intrinsically considered to enhance the importance of population vulnerability when assessing environmental problems, especially in emerging economies.  相似文献   

19.
In the proposed new European chemicals regulations—the REACH system—the improved control of persistent and bioaccumulating substances is stated as one of the tasks being of particular importance. In this article, the reliability and validity of the scientific basis for identification of persistent (P), bioaccumulating (B), and toxic (T) substances, and for assessing the risks that these substances may pose, are discussed. We have used the European Union risk assessment of pentabromodiphenyl ether, PentaBDE (CAS 32534-81-9) as a study case in the analysis. It is concluded that for PBT substances there is room for development both with regard to test methodology and with regard to risk assessment procedures.  相似文献   

20.
The renin-angiotensin system (RAS) and the endothelin system have been implicated in the pathogenesis of human cardiovascular and renal diseases, and inhibition of the RAS markedly improves morbidity and survival. Obesity in humans is associated with an increased risk for the development of hypertension, atherosclerosis and focal-segmental glomerulosclerosis, however the exact mechanisms underlying these pathologies in obese individuals are not known. This article discusses the clinical importance of obesity and the current evidence for local activation of the renin-angiotensin system and its interactions with the endothelin system in obesity and the cardiovascular pathologies associated with it.  相似文献   

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