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921.
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André L. F. Cançado Cibele Q. da-Silva Michel F. da Silva 《Environmental and Ecological Statistics》2014,21(4):627-650
The scan statistic is widely used in spatial cluster detection applications of inhomogeneous Poisson processes. However, real data may present substantial departure from the underlying Poisson process. One of the possible departures has to do with zero excess. Some studies point out that when applied to data with excess zeros, the spatial scan statistic may produce biased inferences. In this work, we develop a closed-form scan statistic for cluster detection of spatial zero-inflated count data. We apply our methodology to simulated and real data. Our simulations revealed that the Scan-Poisson statistic steadily deteriorates as the number of zeros increases, producing biased inferences. On the other hand, our proposed Scan-ZIP and Scan-ZIP+EM statistics are, most of the time, either superior or comparable to the Scan-Poisson statistic. 相似文献
924.
925.
Jeffrey O. Hanson Ana Veríssimo Guillermo Velo-Antón Adam Marques Miguel Camacho-Sanchez Íñigo Martínez-Solano Helena Gonçalves Fernando Sequeira Hugh P. Possingham Silvia B. Carvalho 《Conservation biology》2021,35(2):634-642
Protected-area systems should conserve intraspecific genetic diversity. Because genetic data require resources to obtain, several approaches have been proposed for generating plans for protected-area systems (prioritizations) when genetic data are not available. Yet such surrogate-based approaches remain poorly tested. We evaluated the effectiveness of potential surrogate-based approaches based on microsatellite genetic data collected across the Iberian Peninsula for 7 amphibian and 3 reptilian species. Long-term environmental suitability did not effectively represent sites containing high genetic diversity (allelic richness). Prioritizations based on long-term environmental suitability had similar performance to random prioritizations. Geographic distances and resistance distances based on contemporary environmental suitability were not always effective surrogates for identification of combinations of sites that contain individuals with different genetic compositions. Our results demonstrate that population genetic data based on commonly used neutral markers can inform prioritizations, and we could not find an adequate substitute. Conservation planners need to weigh the potential benefits of genetic data against their acquisition costs. 相似文献
926.
Hemocytes are main blood components of bivalves playing important roles in toxicological and immune responses. Consequently, a study on these cells may be useful to understand the invertebrate immunological systems. The aim of the present study was to find the best antiaggregant solution, based on its capacity of preserving the natural morphology and viability of hemocytes from the freshwater bivalves, Anodonta cygnea, Unio delphinus, and Corbicula fluminea. Hemocytes from the three species were collected and maintained in different antiaggregant solutions, i.e., ethylenediaminetetraacetic acid (EDTA), EDTA-citrate, modified Alsever solution (MAS), N-ethylmaleimide (NEM), NEM-NaCl, and heparin. The cell morphology and viability were analyzed periodically with light microscopy techniques. Between these assays with various antiaggregant solutions, the best results were obtained with NEM at a concentration of 0.05 mol·L?1. It is also shown that, as expected, the osmolarity of the antiaggregant solutions plays a very important role in cell viability. Based on this study, NEM at 0.05 mol·L?1 was considered an adequate antiaggregant solution for future research on immunological and toxicological responses and other physiological studies of freshwater bivalve hemocytes. 相似文献
927.
Muhammet Boran Hikmet Karaçam M. Salih Çelikkale Sevim Köse Muzaffer Feyzioglu Sebahattin Kutlu 《毒物与环境化学》2013,95(1-2):67-73
This paper presents data on the concentrations of 5 metals, copper (Cu), cadmium (Cd), iron (Fe), zinc (Zn) and lead (Pb) in Blue Whiting sampled from the Eastern Black Sea coast of Turkey. The highest metal concentrations of Cu, Cd, Fe, Zn and Pb were recorded in Blue Whiting with the values of 2.71, 0.601, 14.137, 15.322 and 1.078 μg g‐1 dry weight, respectively. On average the metal concentrations in Blue Whiting followed the order of Zn > Fe > Cu > Pb > Cd. Temporal differences of concentrations of these metals were significant (p < 0.05). Spatial fluctuations of Cu, Cd, Fe, Zn and Pb concentrations in Blue Whiting were also significant (p < 0.01). It was found that the concentrations of Cu, Cd, Fe, Zn and Pb in the muscle in Blue Whiting were below the limit of Public Health Regulation in Turkey. 相似文献
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929.
Rodrigo Goyannes Gusmão Caiado Osvaldo Luiz Gonçalves Quelhas Daniel Luiz Mattos Nascimento Rosley Anholon Walter Leal Filho 《国际发展与全球生态学杂志》2018,25(4):312-326
In recent years, sustainability issues are gaining greater prominence among organizations and their stakeholders around the world. This paper aims to verify the sustainability performance of Brazilian organizations in performance measures and to propose sustainable guidelines with the intention of directing future efforts to the transition to sustainable development. The research utilized a triangulated approach by collecting qualitative and quantitative data acquired through multiple collection methods of a theoretical literature review, documentary analysis of corporate reports, questionnaire survey and semi-structured interviews with industry professionals and academic researchers. The results show that internal organizational factors are the main inductors of the sustainable environment in organizations, and sustainability must be tied to strategic planning, starting from upper management to lower levels. It is essential to use sustainable performance measurement systems in order to respond to external and internal levers and serve as benchmarking for future corporate operations and strategies. In addition, it is the responsibility of organizations to focus their efforts on environmental protection, reduction of energy, corporate reputation, quality management, customer satisfaction and investor relations, as they are considered to be more important and have a relationship of dependence on organizational sustainability. The findings will be of value to professionals and academics who want to start measuring and for continuously improving the sustainability performance of their organizations according to the technical, economic, environmental, social and governance dimensions. This research work also helps to understand the perceptions and expectations of stakeholders. 相似文献
930.
A ‘coastal-hazard GIS’ for Sri Lanka 总被引:1,自引:1,他引:0
Jean-François Desprats Manuel Garcin Nishanta Attanayake Rodrigo Pedreros Cheer Siriwardana Mélanie Fontaine Starin Fernando Udaya De Silva 《Journal of Coastal Conservation》2010,14(1):21-31
Following the 2004 tsunami disaster in Sri Lanka, it was apparent that mapping the coast’s vulnerability was essential for
future protection of the local populations. We therefore developed a prototype ‘Coastal-hazard GIS’ for Sri Lanka so as to
provide an effective tool for decision makers to limit the impact of natural coastal hazards such as sea level rise, tsunamis,
storm surges and coastal erosion, and thus protect the exposed assets (population, property, settlements, communications networks,
etc.). The prototype was developed on a pilot site in Galle through building up homogeneous data on the land/sea interface
from studies conducted on the exposure of the coastal populations, the aim being to enable an evaluation of the hazards combined
with the vulnerability and thus an analysis of the risks. Coastal risk scenarios are developed so as to estimate the impacts
and consequences of an event (tsunami, storm, etc.) on the assets, the principle behind this being that if, in general, the
coastal hazard cannot be decreased, then a better knowledge of it through simulation should make it possible to limit the
vulnerability and thus the risk. The Coastal-hazard GIS will also provide a planning tool in terms of locating new settlements,
expanding urban areas, siting coastal protection works, etc. 相似文献