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The anthropogenic increase in aerosol concentrations since preindustrial times and its net cooling effect on the atmosphere is thought to mask some of the greenhouse gas-induced warming. Although the overall effect of aerosols on ...
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The anthropogenic increase in aerosol concentrations since preindustrial times and its net cooling effect on the atmosphere is thought to mask some of the greenhouse gas-induced warming. Although the overall effect of aerosols on solar radiation and clouds is most certainly negative, some individual forcing agents and feedbacks have positive forcing effects. Recent studies have tried to identify some of those positive forcing agents and their individual emission sectors, with the hope that mitigation policies could be developed to target those emitters. Understanding the net effect of multisource emitting sectors and the involved cloud feedbacks is very challenging, and this paper will clarify forcing and feedback effects by separating direct, indirect, semidirect and surface albedo effects due to aerosols. To this end, we apply the Goddard Institute for Space Studies climate model including detailed aerosol microphysics to examine aerosol impacts on climate by isolating single emission sector contributions as given by the Coupled Model lntercomparison Project Phase 5 (CMIP5) emission data sets developed for Intergovernmental Panel on Climate Change (IPCC) AR5. For the modeled past 150 years, using the climate model and emissions from preindustrial times to present-day, the total global annual mean aerosol radiative forcing is -0.6 W/m~2, with the largest contribution from the direct effect (-0.5 W/m~2). Aerosol-induced changes on cloud cover often depends on cloud type and geographical region. The indirect (includes only the cloud albedo effect with -0.17 W/m~2) and semidirect effects (-0.10 W/m~2) can be isolated on a regional scale, and they often have opposing forcing effects, leading to overall small forcing effects on a global scale. Although the surface albedo effects from aerosols are small (0.016 W/m~2), triggered feedbacks on top of the atmosphere (TOA) radiative forcing can be 10 times larger. Our results point out that each emission sector has varying impacts by geographical region. For example, the single sector most responsible for a net positive radiative forcing is the transportation sector in the United States, agricultural burning and transportation in Europe, and the domestic emission sector in Asia. These sectors are attractive mitigation targets.
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Deterrence and incapacitation effects of auto theft are estimated with a full consideration of substitution effects across crime types and across districts in a closed area in which none of the effects will leak out. It is found t...
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Deterrence and incapacitation effects of auto theft are estimated with a full consideration of substitution effects across crime types and across districts in a closed area in which none of the effects will leak out. It is found that the increase in the cleared rate of auto theft crime in a certain district and in other districts strongly deters the auto theft in that district, indicating that the across-district deterrence effect dominates the across-district substitution effect. The across-crime deterrence effect significantly exceeds the across-crime substitution effect for close crime (general theft), but is insignificant for distant crime (violence).
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The framing effect demonstrates that two options with different risk levels affect people's risk preferences, even if both options are logically equivalent. However, in reality we are almost always confronted with more than two ch...
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The framing effect demonstrates that two options with different risk levels affect people's risk preferences, even if both options are logically equivalent. However, in reality we are almost always confronted with more than two choices, rather than a single manipulated message. In this paper, we simultaneously manipulate the framing effect and the context effect, including the attraction effect and the compromise effect, to examine the influence of context on framing. The results of two studies show that context influences the original choice preference arising from the framing effect. Moreover, the framing effect is reduced when context effects are introduced to the original choice set.
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The framing effect demonstrates that two options with different risk levels affect people’s risk preferences, even if both options are logically equivalent. However, in reality we are almost always confronted with more than two c...
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The framing effect demonstrates that two options with different risk levels affect people’s risk preferences, even if both options are logically equivalent. However, in reality we are almost always confronted with more than two choices, rather than a single manipulated message. In this paper, we simultaneously manipulate the framing effect and the context effect, including the attraction effect and the compromise effect, to examine the influence of context on framing. The results of two studies show that context influences the original choice preference arising from the framing effect. Moreover, the framing effect is reduced when context effects are introduced to the original choice set.
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Past research has provided evidence that customers' affective responses to service packages, or bundles, include aspects related to the content of the bundle and the timing of bundle elements, or events. Service design efforts tha...
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Past research has provided evidence that customers' affective responses to service packages, or bundles, include aspects related to the content of the bundle and the timing of bundle elements, or events. Service design efforts that attempt to maximize these affective responses may be inhibited by the degree to which an event is flexible across time and across contextual fit. This article uses numerical simulation of an artificial problem to test hypotheses about the impact of timing flexibility and contextual-fit flexibility on affect-based design efforts and provides insight about how differing levels of flexibility constrain or enable designers' ability to create bundles and schedules that adhere to behavioral-based design attributes such as the peak, end, trend, and spread effects. Our findings suggest that different kinds of flexibility enable affect-based schedules in different manners, and managers should consider the impact that flexibility will have on successful affect-based scheduling efforts.
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This brief paper supplements the review by A F Barabanov et al. (Physics-Uspekhi 58 446 (2015)) concerning the Hall and Righi-Leduc effects. Both effects are diagonal in the sense that the initial current perpendicular to the magn...
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This brief paper supplements the review by A F Barabanov et al. (Physics-Uspekhi 58 446 (2015)) concerning the Hall and Righi-Leduc effects. Both effects are diagonal in the sense that the initial current perpendicular to the magnetic field and the transverse response (perpendicular to both the magnetic field and the initial current) are of the same nature (the electric current in the Hall effect and the heat current in the Righi-Leduc effect). We here take a similar perspective in discussing the nondiagonal Ettingshausen and Nernst effects, in which the transverse current is different in nature from the initial longitudinal one. A summary of transverse effects in a magnetic field is also given.
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Standardisation is a key part of the microeconomic infrastructure with the benefits arising from the reduction of costs and the growth of quality. Although standardisation cannot raise profitability in all companies, still, it is ...
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Standardisation is a key part of the microeconomic infrastructure with the benefits arising from the reduction of costs and the growth of quality. Although standardisation cannot raise profitability in all companies, still, it is in the interests of the economy as a whole, because it encourages competition. This research aims to raise awareness on the importance of standardisation activities, its economic and other effects, as well as the importance of taking part in the process of developing standards within the national standardisation bodies. The data used in this paper are the result of the research conducted at the Institute for Standardization of Serbia, Belgrade, 2015, where we have been examining the potential effects of standardisation. For the analysis of the obtained results, we used the methodology of structural equation modelling, which includes evaluating the measurement model, and based on an adequate index fitting, a structural model was tested, by using the appropriate statistical methods. The results of research in this paper confirm the positive relationship between perceived effects of standardisation as innovative, economic, technical-technological and social effects.
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The quest to understand the multilevel antecedents of competitiveness has led to a separation of approaches. On one side of the question are the environment theories that analyze the structural characteristics of the general and c...
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The quest to understand the multilevel antecedents of competitiveness has led to a separation of approaches. On one side of the question are the environment theories that analyze the structural characteristics of the general and competitive environment. On the other side are the Resource Based View and its extensions that highlight firm-specific resources and capabilities as the main basis of firms' competitiveness. However, in recent years the nature of competition and shifting economic conditions have given rise to new theoretical approaches that complement the assumptions underlying both environmental and firm theories. Specifically, this study contributes by examining the regional environment effect, the district effect and the strategic group effect. Through a study of 364 Spanish tourism firms, this research explores the relative importance of distinct external forces such as the general environment or country effect, the regional effect, the competitive environment or industry effect, the district effect, and internal factors such as the firm's tangible resources, capabilities and strategy selection. The results demonstrate that firms' capabilities are more important than environment effects and tangible resources. (C) 2015 Elsevier Ltd. All rights reserved.
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This review discusses main directions and results of the studies on antibiotics produced by bacteria living in the marine environment. In recent years many obligate marine species and strains were studied, diverse metabolites were...
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This review discusses main directions and results of the studies on antibiotics produced by bacteria living in the marine environment. In recent years many obligate marine species and strains were studied, diverse metabolites were isolated, and their chemical structures were elucidated. Among them here were natural compounds toxic against tumor cells, pathogenic bacteria, viruses, and malaria plasmodial species; these compounds often had no analogues among the natural products of terrestrial origin. Some isolated compounds form a basis of active ingredients in medicinal preparations used in clinic practice, while others are under different stages of preclinical or clinical studies. Much attention has been paid in recent years to producers of marine-derived antibiotics isolated from the deep-sea habitats, from the surface of marine invertebrates and algae, as well as from symbiotic microorganisms.
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Crossover designs are used by a high proportion of studies investigating the effects of transcranial direct current stimulation (tDCS) on motor learning. These designs necessitate attention to aspects of data collection and analys...
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Crossover designs are used by a high proportion of studies investigating the effects of transcranial direct current stimulation (tDCS) on motor learning. These designs necessitate attention to aspects of data collection and analysis to take account of design-related confounds including order, carryover, and period effects. In this systematic review, we appraised the method sections of crossover-designed tDCS studies of motor learning and discussed the strategies adopted to address these factors. A systematic search of 10 databases was performed and 19 research papers, including 21 experimental studies, were identified. Potential risks of bias were addressed in all of the studies, however, not in a rigorous and structured manner. In the data collection phase, unclear methods of randomization, various lengths of washout period, and inconsistency in the counteracting period effect can be observed. In the analytical procedures, the stratification by sequence group was often ignored, and data were treated as if it belongs to a simple repeated-measures design. An inappropriate use of crossover design can seriously affect the findings and therefore the conclusions drawn from tDCS studies on motor learning. The results indicate a pressing need for the development of detailed guidelines for this type of studies to benefit from the advantages of a crossover design.
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