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101.
    
Adverse childhood experiences might have long-lasting effects on decisions under uncertainty in adult life. Merging the European Survey on Health, Ageing and Retirement with data on conflict events during the Second World War, and relying on region-by-cohort variation in war exposure, we show that warfare exposure during childhood is associated with lower financial risk taking in later life. Individuals who experienced war episodes as children hold less – and are less likely to hold – stocks, but are more likely to hold life insurance, compared to non-exposed individuals. Effects are robust to the inclusion of potential mediating factors, and are tested for nonlinearity and heterogeneity. Moreover, we provide evidence of hedonic adaptation to war, as high and low intensity of war exposure have comparable long-term effects. We also document that war exposure in childhood increases sensitivity to financial uncertainty since exposed-to-war individuals are less likely to hold stocks after periods of high volatility. Finally, we shed light on the most likely mechanism in the relationship between war exposure and financial risk taking – i.e., enhanced sensitivity to uncertainty – and we show that preferences, and not beliefs, channel this relationship.  相似文献   
102.
    
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103.
3D printing (3DP) has been heralded as a revolutionary technology that can alter the way production is organized across time and space – with important redistributive effects on geography and size of production activities. In this article, we examine the impacts that a widespread adoption of 3DP could have on restructuring, upgrading and distributing value added along manufacturing global value chains (GVC) – with brief examples from the aerospace and automotive industries. We highlight two possible scenarios for GVCs – a complementarity scenario of 3DP and traditional manufacturing overlapping, which would reproduce power relations in GVCs and the current distribution of value added in a ‘smiling curve’; and a substitution scenario of 3DP partly or fully superseding traditional manufacturing, which would have more transformational effects in terms of ‘rebundling’ activities, regionalizing or localizing GVCs, and flattening the smiling curve into a ‘smirk’.  相似文献   
104.
This study assesses the association of 12th-grade student factors (e.g., grades, classroom misbehaviors) with substance use (i.e., binge drinking, cigarette smoking, marijuana) across large, medium-sized, and nonmetropolitan areas. Based on a sample of 2,189 students from the 2013 Monitoring the Future data set, logistic regression analyses showed that poor student academic and behavioral factors were associated with higher substance use after controlling for gender, race, and socioeconomic status. Interaction analyses further showed no significant differences in the influence of student factors on substance use across locales. Results suggest that prevention efforts against substance use should target student factors regardless of area of residency.  相似文献   
105.
    
Research has found significant benefits in using exercise as an adjunct treatment for substance use. This study used a qualitative grounded theory approach to explore the role of group exercise on maintaining sobriety. Sixteen persons (13 White men and 3 White women, age M = 31.81, SD = 8.23), recruited from a substance use recovery group that meets at a gym in an urban area in the Southeast part of the United States, were individually interviewed. Data were analyzed using Charmaz’s (2006) constructivist grounded theory strategies. Central themes revealed a parallel process between the steps taken to seek sobriety and those taken to maintain sobriety. The driving forces of sobriety success in both was 12 steps and group exercise programming that included elements of mentorship, structure, accountability, and fellowship or community. This study supported the use of physical group exercise as an adjunct treatment option for substance use treatment.  相似文献   
106.
    
Microfluidic devices are now the most promising tool to mimic in vivo like scenarios such as tumorigenesis and metastasis due to its ability to more closely mimic cell's natural microenvironment (such as 3D environment and continuous perfusion of nutrients). In this study, the ability of 2% and 3% enzymatically crosslinked silk fibroin hydrogels with different mechanical properties are tested in terms of colorectal cancer cell migration, under different microenvironments in a 3D dynamic model. Matrigel is used as control. Moreover, a comprehensive comparison between the traditional Boyden chamber assay and the 3D dynamic microfluidic model in terms of colorectal cancer cell migration is presented. The results show profound differences between the two used biomaterials and the two migration models, which are explored in terms of mechanical properties of the hydrogels as well as the intrinsic characteristics of the models. Moreover, the developed 3D dynamic model is validated by demonstrating that hVCAM-1 plays a major role in the extravasation process, influencing extravasation rate and traveled distance. Furthermore, the developed model enables precise visualization of cancer cell migration within a 3D matrix in response to microenvironmental cues, shedding light on the importance of biophysical properties in cell behavior.  相似文献   
107.
A system of predictors for estimating a finite population variance is defined and shown to be asymptotically design-unbiased (ADU) and asymptotically design-consistent (ADC) under probability sampling. An asymptotic mean squared error (MSE) of a generalized regression-type predictor, generated from the system, is obtained. The suggested predictor attains the minimum expected variance of any design-unbiased estimator when the superpopulation model is correct. The generalized regression-type predictor and the predictor suggested by Mukhopadhyay (1990) are compared.  相似文献   
108.
Employing certain generalized random permutation models and a general class of linear estimators of a finite population mean, it is shown that many of the conventional estimators are “optimal” in the sense of minimum average mean square error. Simple proofs are provided by using a well-known theorem on UMV estimation. The results also cover certain simple response error situations.  相似文献   
109.
This paper explores the dialectic of place and community identity in Mount Pleasant, a multi–ethnic and multi–class U.S. neighborhood where definitions of place are hotly contested among its residents. In a grant proposal for public toilets, Mount Pleasant writers use linguistic strategies such as presupposition, deixis, and contrast, coupled with discursive themes of filth and geography, to construct a core of the Mount Pleasant community. The writers place themselves and people who share their values in that core, and immigrants at the margins. These strategies serve as a discursive type of spatial purification practice (cf. Sibley 1988) through which the grantwriters set up a moral and spatial order where they and other core community members are deemed to use space ‘appropriately’, and thus inhabit positive moral positions, while immigrant community members’ imputed ‘inappropriate’ use of space is used to construct negative moral positions for them.  相似文献   
110.
We demonstrate to decision makers how to optimally make costly strategic pre-investment R&D decisions in the presence of spillover effects in an option pricing framework with analytic tractability. Decisions are modeled as impulse-type controls with random outcome. Two firms face two decisions that are solved interdependently in a two-stage game. The first-stage decision is: What is the optimal level of coordination (optimal policy/technology choice)? The second-stage decision is: What is the optimal effort for a given level of the spillover effects and the cost of information acquisition? The framework is extended to a two-period closed-loop stochastic game with (path-dependency inducing) switching costs that make strategy revisions harder. When conditions of learning-by-doing exist, we find that strategy shifts are easier to observe in market environments of high growth and high volatility.  相似文献   
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