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941.
Omran E. Frihy Mahmoud Kh. El-Sayed 《Mitigation and Adaptation Strategies for Global Change》2013,18(8):1215-1237
Consequence of the sea level rise (SLR) on the Mediterranean coastal areas in Egypt, particularly the Nile River Delta, has become an issue of major concern to Egypt’s population and the government. Previous publications disregard the entire Mediterranean coast of Egypt as an integral unit subject to the impacts of the SLR. This study aims to analyzing the risks, ranking the vulnerability and suggesting adaptation measures to mitigate the impact of the SLR along the Mediterranean coast of Egypt. Although the prominent features of Egypt’s Mediterranean coastal zone are the low lying coast of the Nile Delta, associated with land subsidence, tectonic activities and erosion; the contiguous coastal sectors are backed by shore-parallel carbonate ridges and Plateau (the western coast) and sand dune belts (Sinai coast). The coastal zone is ranked as high, moderate, and low vulnerable to the SLR. The social and biophysical vulnerabilities demonstrate the asymmetrical impacts of the SLR on the Mediterranean coast of Egypt. Areas at risk in the Alexandria region are Mandara and El Tarh whereas in the Nile Delta region, they are the Manzala Lagoon barrier, east and west of the Rosetta City, Gamil, and the Tineh plain. Risk associated with these impacts may be reduced provided the consideration of immediate and adequate adaptation measures. 相似文献
942.
Antonella?De?DonnoEmail author Tiziana?Grassi Francesco?Bagordo Adele?Idolo Francesca?Serio Giovanni?Gabutti 《Food and environmental virology》2012,4(2):81-88
The purpose of this study was to demonstrate that shellfish can be used to detect enteric viruses in marine waters where they
are present at very low concentrations. Aqua-cultured mussels were placed in the sea just off the mouth of a drainage channel
affected by human and animal faecal contamination. Samples were taken from the channel, the sea and the mussels at intervals
over two 4-week periods. The samples were tested to verify the presence of both rotaviruses and E. coli. Rotaviruses were detected by Real Time-PCR, typed by multiplex PCR and subsequently sequenced. E. coli was enumerated in water matrices by a filtering method and in mussels by the MPN method. The presence of E. coli in the examined matrices demonstrates contamination of faecal origin throughout the studied environments. Rotaviruses were
recorded in channel waters, but not in sea water. In both experiments, rotaviruses were detected in mussels 21 and 28 days
after being placed in the sea water off the channel mouth. The use of mussels thus enabled the detection of rotaviruses in
waters where the high dilution rendered direct investigation impossible. This study indicates that mussels can be used in
marine virological surveillance programs. 相似文献
943.
Chandra Nath Shiv G. Kapoor Richard E. DeVor Anil K. Srivastava Jon Iverson 《Journal of Manufacturing Processes》2012,14(4):452-459
Tool life has been a vital issue in machining titanium alloys. Recently, an atomization-based cutting fluid (ACF) application has been found to be an effective approach for cooling and lubrication in micromachining operations. In this study, an ACF spray system is developed for macro-scale turning of Ti–6Al–4V. The spray system is designed to minimize interaction between the fluid droplets, and the gas nozzle to control the divergence of the fluid droplets. Experiments are conducted to study the effect of five specific ACF spray parameters including fluid flow rate, spray distance, impingement angle, and type and pressure level of the droplet carrier gas on cutting forces, tool life, and chip characteristics. It has been observed that the combination of lower pressure (150 psi) air-mixed CO2 with a higher flow rate (20 ml/min) and a larger spray distance (35 mm) produces a significantly longer tool life and broken chips. The results also reveal that the ACF spray system can extend tool life up to 40–50% over flood cooling. 相似文献
944.
Building regional priorities in forests for development and adaptation to climate change in the Congo Basin 总被引:1,自引:0,他引:1
Denis J. Sonwa Johnson N. Nkem Monica E. Idinoba Mekou Y. Bele Cyprain Jum 《Mitigation and Adaptation Strategies for Global Change》2012,17(4):441-450
Indentifying common priorities in shared natural resource systems constitutes an important platform for implementing adaptation
and a major step in sharing a common responsibility in addressing climate change. Predominated by discourses on REDD + (Reduced
Emissions from Deforestation and Forest Degradation and conservation, sustainable management of forests and enhancement of
forest carbon stocks in developing countries) with little emphasis on adaptation there is a risk of lack of policy measures
in addressing climate change in the Congo Basin. Forest products and ecosystem services provide security portfolios for the
predominantly rural communities, and play major roles in national development programmes in both revenue and employment opportunities.
Thus, raising the profile of forests in the policy arena especially in the twin roles of addressing climate change in mitigation
and adaptation and achieving resilient development is crucial. Within the framework of the Congo Basin Forests and Climate
Change Adaptation project (COFCCA) project, science policy dialogue was conducted to identify and prioritize forest based
sectors vulnerable to climate change but important to household livelihoods and national development. The goal of the prioritization
process was for the development of intervention in forest as measures for climate change adaptation in Central Africa. Participants
constituted a wide range of stakeholders (government, Non Governmental Organizations, research institutions, universities,
community leaders, private sectors etc.) as representatives from three countries directly involved in the project: Cameroon,
Central African Republic and Democratic Republic of Congo. Building on national priorities, four forest related sectors were
identified as common priorities at the regional level for focus on climate change adaptation. These sectors included: (1)
energy with emphasis on fuel wood and Charcoal; (2) Water principally quality, quantity, accessibility, etc.; (3) Food with emphasis on Non Timber Forest Products, and (4) Health linked to healthcare products (medicinal plants). Using these prioritized sectors, the project focused on addressing the impacts of climate change on local communities and the development of adaptation strategies in the three pilot countries
of the Congo Basin region. The four sectors constitute the key for development in the region and equally considered as priority sectors in the poverty
reduction papers. Focused research on these sectors can help to inject the role of forests in national and local development
and their potentials contributions to climate change adaptation in national and public discourses. Mainstreaming forest for
climate change adaptation into national development planning is the key to improve policy coherence and effectiveness in forest
management in the region. 相似文献
945.
Simon?BrinerEmail author Michael?Hartmann Robert?Finger Bernard?Lehmann 《Mitigation and Adaptation Strategies for Global Change》2012,17(4):337-355
We assessed the economic suitability of 4 greenhouse gas (GHG) mitigation options and one GHG offset option for an improvement
of the GHG balance of a representative Swiss suckler cow farm housing 35 Livestock units and cultivating 25 ha grassland.
GHG emissions per kilogram meat in the economic optimum differ between the production systems and range from 18 to 21.9 kg
CO2-eq./kg meat. Only GHG offset by agroforestry systems showed the potential to significantly reduce these emissions. Depending
on the production system agroforestry systems could reduce net GHG emissions by 66% to 7.3 kg CO2-eq./kg meat in the most intensive system and by 100% in the most extensive system. In this calculation a carbon sequestration
rate of 8 t CO2/ha/year was assumed. The potential of a combination of the addition of lipids to the diet, a cover of the slurry tank and
the application of nitrification inhibitors only had the potential to reduce GHG emissions by 12% thereby marginal abatement
costs are increasing much faster than for agroforestry systems. A reduction of the GHG emissions to 7.5 kg CO2-eq./kg meat—possible with agroforestry only—raised costs between 0.03 CHF/kg meat and 0.38 CHF/kg meat depending on the production
system and the state of the system before the reduction. If GHG emissions were reduced maximally average costs ranged between
0.37 CHF/kg meat, if agroforestry had the potential to reduce net GHG emissions to 0 kg CO2-eq., to 1.17 CHF/kg meat if also other options had to be applied. 相似文献
946.
J. S. Rice R. H. Moss P. J. Runci K. L. Anderson E. L. Malone 《Mitigation and Adaptation Strategies for Global Change》2012,17(7):805-819
A new modeling effort exploring the opportunities, constraints, and interactions between mitigation and adaptation at regional scale is utilizing stakeholder engagement in an innovative approach to guide model development and demonstration, including uncertainty characterization, to effectively inform regional decision making. This project, the integrated Regional Earth System Model (iRESM), employs structured stakeholder interactions and literature reviews to identify the most relevant adaptation and mitigation alternatives and decision criteria for each regional application of the framework. The information is used to identify important model capabilities and to provide a focus for numerical experiments. This paper presents the stakeholder research results from the first iRESM pilot region. The pilot region includes the Great Lakes Basin in the Midwest portion of the United States as well as other contiguous states. This geographic area (14 states in total) permits cohesive modeling of hydrologic systems while also providing strong gradients in climate, demography, land cover/land use, and energy supply and demand. The results from the stakeholder research indicate that, for this region, iRESM should prioritize addressing adaptation alternatives in the water resources, urban infrastructure, and agriculture sectors, including water conservation, expanded water quality monitoring, altered reservoir releases, lowered water intakes, urban infrastructure upgrades, increased electric power reserves in urban areas, and land use management/crop selection changes. For mitigation in this region, the stakeholder research implies that iRESM should focus on policies affecting the penetration of renewable energy technologies, and the costs and effectiveness of energy efficiency, bioenergy production, wind energy, and carbon capture and sequestration. 相似文献
947.
Modeling and interpretation of fiber orientation-based failure mechanisms in machining of carbon fiber-reinforced polymer composites 总被引:1,自引:0,他引:1
Kevin A. Calzada Shiv G. Kapoor Richard E. DeVor Johnson Samuel Anil K. Srivastava 《Journal of Manufacturing Processes》2012,14(2):141-149
The development and implementation of a microstructure-based finite element model for the machining of carbon fiber-reinforced polymer composites is presented. A new approach to interfacial modeling is introduced where the material interface is modeled using continuum elements, allowing failure to take place in either tension or compression. The model is capable of describing the fiber failure mode occurring throughout the chip formation process. Characteristic fiber length in the chips, and machining forces for microstructures with fibers orientated at 0°, 45°, 90°, and 135° are examined. For model validation purposes, the model-based machining performance predictions are compared to the machining responses from a set of orthogonal machining experiments. A parametric study is presented that identifies a robust tool geometry, which minimizes the effects of fiber orientation and size on the machining forces. 相似文献
948.
PROBLEM: Safety-belt use reduces motor vehicle crash-related morbidity and mortality, yet an estimated 18% of drivers do not consistently buckle up (NHTSA, 2005). In 1985, Geller and colleagues developed an interpersonal Flash-for-Life prompt that increased belt use among 22% of 1,087 unbuckled drivers (Geller, Bruff, & Nimmer, 1985). METHOD: The Flash-for-Life intervention was re-introduced at a large university with high safety-belt use (i.e., 80%). College students stood at parking-lot entrance/exits and "flashed" signs with the message, "Please Buckle Up, I Care" to unbuckled drivers. RESULTS: Of 427 unbuckled drivers observed, 30% of these complied with the prompt. Male drivers were significantly more likely to comply with prompts delivered by females. DISCUSSION: Compliance was higher than in the 1985 study, indicating a high baseline rate of safety-belt use does not negate potential beneficial influence of a prompting intervention. This intervention is particularly effective with college-aged males, a sub-group of the driving population least likely to buckle-up. IMPACT ON INDUSTRY: A simple behavioral prompt could be used at most industrial complexes to increase safety-belt use among vehicle occupants who are not buckled-up. 相似文献
949.
The predictive validity of safety climate 总被引:1,自引:0,他引:1
Johnson SE 《Journal of Safety Research》2007,38(5):511-521
PROBLEM: Safety professionals have increasingly turned their attention to social science for insight into the causation of industrial accidents. One social construct, safety climate, has been examined by several researchers [Cooper, M. D., & Phillips, R. A. (2004). Exploratory analysis of the safety climate and safety behavior relationship. Journal of Safety Research, 35(5), 497-512; Gillen, M., Baltz, D., Gassel, M., Kirsch, L., & Vacarro, D. (2002). Perceived safety climate, job Demands, and coworker support among union and nonunion injured construction workers. Journal of Safety Research, 33(1), 33-51; Neal, A., & Griffin, M. A. (2002). Safety climate and safety behaviour. Australian Journal of Management, 27, 66-76; Zohar, D. (2000). A group-level model of safety climate: Testing the effect of group climate on microaccidents in manufacturing jobs. Journal of Applied Psychology, 85(4), 587-596; Zohar, D., & Luria, G. (2005). A multilevel model of safety climate: Cross-level relationships between organization and group-level climates. Journal of Applied Psychology, 90(4), 616-628] who have documented its importance as a factor explaining the variation of safety-related outcomes (e.g., behavior, accidents). Researchers have developed instruments for measuring safety climate and have established some degree of psychometric reliability and validity. The problem, however, is that predictive validity has not been firmly established, which reduces the credibility of safety climate as a meaningful social construct. The research described in this article addresses this problem and provides additional support for safety climate as a viable construct and as a predictive indicator of safety-related outcomes. METHODS: This study used 292 employees at three locations of a heavy manufacturing organization to complete the 16 item Zohar Safety Climate Questionnaire (ZSCQ) [Zohar, D., & Luria, G. (2005). A multilevel model of safety climate: Cross-level relationships between organization and group-level climates. Journal of Applied Psychology, 90(4), 616-628]. In addition, safety behavior and accident experience data were collected for 5 months following the survey and were statistically analyzed (structural equation modeling, confirmatory factor analysis, exploratory factor analysis, etc.) to identify correlations, associations, internal consistency, and factorial structures. RESULTS: Results revealed that the ZSCQ: (a) was psychometrically reliable and valid, (b) served as an effective predictor of safety-related outcomes (behavior and accident experience), and (c) could be trimmed to an 11 item survey with little loss of explanatory power. IMPACT ON INDUSTRY: Practitioners and researchers can use the ZSCQ with reasonable certainty of the questionnaire's reliability and validity. This provides a solid foundation for the development of meaningful organizational interventions and/or continued research into social factors affecting industrial accident experience. 相似文献
950.
Population dynamics and regulation in the cave salamander <Emphasis Type="Italic">Speleomantes strinatii</Emphasis> 总被引:1,自引:0,他引:1
Salvidio S 《Die Naturwissenschaften》2007,94(5):396-400
Time series analysis has been used to evaluate the mechanisms regulating population dynamics of mammals and insects, but has
been rarely applied to amphibian populations. In this study, the influence of endogenous (density-dependent) and exogenous
(density-independent) factors regulating population dynamics of the terrestrial plethodontid salamander Speleomantes strinatii was analysed by means of time series and multiple regression analyses. During the period 1993–2005, S. strinatii population abundance, estimated by a standardised temporary removal method, displayed relatively low fluctuations, and the
autocorrelation function (ACF) analysis showed that the time series had a noncyclic structure. The partial rate correlation
function (PRCF) indicated that a strong first-order negative feedback dominated the endogenous dynamics. Stepwise multiple
regression analysis showed that the only climatic factor influencing population growth rate was the minimum winter temperature.
Thus, at least during the study period, endogenous, density-dependent negative feedback was the main factor affecting the
growth rate of the salamander population, whereas stochastic environmental variables, such as temperature and rainfall, seemed
to play a minor role in regulation. These results stress the importance of considering both exogenous and endogenous factors
when analysing amphibian long-term population dynamics. 相似文献