Social Context of Smoking Hookah Among College Students: Scale Development and Validation

Abstract

Objective: To develop an instrument that measures the social context of hookah use among college students. Participants: A pool of 50 potential items, based on 44 in-depth interviews with regular college hookah smokers, was administered to a sample of 274 hookah users between October and December 2011. Methods: Participants were approached in hookah bars and asked to complete the survey. Results: A principle components analysis revealed 3 reliable factors: social facilitation, family/cultural influence, and alternative to smoking cigarettes and drinking. These were examined across different categories of hookah use: Weekly hookah users were more likely to smoke in a context of social facilitation than the other 2 groups. Similar effects were observed for family/cultural influence. Asians were more likely to smoke in a context of family and cultural influence than non-Asians. Conclusions: This scale has potential for identifying situation-specific contexts of hookah use that may help in designing effective interventions for college students.     

A Predictive Model for Survival of Escherichia coli O157:H7 and Generic E. coli in Soil Amended with Untreated Animal Manure

This study aimed at developing a predictive model that captures the influences of a variety of agricultural and environmental variables and is able to predict the concentrations of enteric bacteria in soil amended with untreated Biological Soil Amendments of Animal Origin (BSAAO) under dynamic conditions. We developed and validated a Random Forest model using data from a longitudinal field study conducted in mid-Atlantic United States investigating the survival of Escherichia coli O157:H7 and generic E. coli in soils amended with untreated dairy manure, horse manure, or poultry litter. Amendment type, days of rain since the previous sampling day, and soil moisture content were identified as the most influential agricultural and environmental variables impacting concentrations of viable E. coli O157:H7 and generic E. coli recovered from amended soils. Our model results also indicated that E. coli O157:H7 and generic E. coli declined at similar rates in amended soils under dynamic field conditions.The Random Forest model accurately predicted changes in viable E. coli concentrations over time under different agricultural and environmental conditions. Our model also accurately characterized the variability of E. coli concentration in amended soil over time by providing upper and lower prediction bound estimates. Cross-validation results indicated that our model can be potentially generalized to other geographic regions and incorporated into a risk assessment for evaluating the risks associated with application of untreated BSAAO. Our model can be validated for other regions and predictive performance also can be enhanced when data sets from additional geographic regions become available.     

On Variance Upper Bounds for Unimodal Distributions

We obtain upper bounds on the variance of discrete unimodal distributions. The alternative proofs of the corresponding bounds for the continuous unimodal distributions are also given.     

Bayesian analysis of head and neck cancer data using generalized inverse Lindley stress–strength reliability model

In this article, we present the analysis of head and neck cancer data using generalized inverse Lindley stress–strength reliability model. We propose Bayes estimators for estimating P(X > Y), when X and Y represent survival times of two groups of cancer patients observed under different therapies. The X and Y are assumed to be independent generalized inverse Lindley random variables with common shape parameter. Bayes estimators are obtained under the considerations of symmetric and asymmetric loss functions assuming independent gamma priors. Since posterior becomes complex and does not possess closed form expressions for Bayes estimators, Lindley’s approximation and Markov Chain Monte Carlo techniques are utilized for Bayesian computation. An extensive simulation experiment is carried out to compare the performances of Bayes estimators with the maximum likelihood estimators on the basis of simulated risks. Asymptotic, bootstrap, and Bayesian credible intervals are also computed for the P(X > Y).     

Estimation of the mean of the selected gamma population

Let л₁ and л₂ denote two independent gamma populations G(α₁, p) and G(α₂, p) respectively. Assume α(i=1,2)are unknown and the common shape parameter p is a known positive integer. Let Y_i denote the sample mean based on a random sample of size n from the i-th population. For selecting the population with the larger mean, we consider, the natural rule according to which the population corresponding to the larger Y_i is selected. We consider? in this paper, the estimation of M, the mean of the selected population. It is shown that the natural estimator is positively biased. We obtain the uniformly minimum variance unbiased estimator(UMVE) of M. We also consider certain subclasses of estikmators of the form c₁x₍₁₎ +c₁x₍₂₎ and derive admissible estimators in these classes. The minimazity of certain estimators of interest is investigated. Itis shown that p(p+1)^-1x₍₁₎ is minimax and dominates the UMVUE. Also UMVUE is not minimax.     

外包趋势不可逆 奥巴马的政治限制影响甚微

自从奥巴马接任美国总统以来，严重依赖美国的印度外包产业一度感到胆战心惊：首先，奥巴马大幅减少了允许外国工人在美国本土就业的H-1b工作签证；接着奥巴马又在2月24日的国会讲话中宣布“终止美国公司外包业务的减税优惠”。     

Subsidiary power,cultural intelligence and interpersonal knowledge transfer between subsidiaries within the multinational enterprise

We propose that individual-level knowledge transfer between subsidiaries within a multinational enterprise depends on the perceived relative power of the subsidiary and the cultural intelligence of individuals. Using a sample of 333 research and development (R&D) subsidiary employees of foreign Multinational Enterprises (MNEs) in India, we find that the perceived subsidiary power has a direct positive significant effect on knowledge sharing, and an indirect significant effect, through organizational identification, on knowledge seeking. Further, cultural intelligence moderates the effect of organizational identification on knowledge seeking, and the indirect effect of the perceived subsidiary power on it. The findings highlight the role of organizational identification and cultural intelligence in explaining the impact of the perceived subsidiary power on interpersonal knowledge transfer within the MNE.     

The intersection of social protection and mobilities: a move towards a ‘Practical Utopia’ research agenda

Currently, a number of contributions in mobility studies are looking for fruitful intersections with other ‘adjacent’ approaches . In this spirit, our theoretical paper argues to study one particular aspect: the intersection of social protection and mobilities. Currently, the provision of social services in the ‘West’ is strongly entrenched within nation-state logics, which assume that clients’ immobility is a precondition of service delivery and that national citizenship is the desirable conditionality of gaining social rights. To overcome such a wide-spread conflation of social security with state security, we introduce the heuristic concept ‘social protection’. It allows social security to be imagined beyond a state-centric perspective and avoids the pitfalls of either a citizenship or a migration approach by taking on a mobility perspective. Thus, for scholars anchored in mobility studies we propose how to develop a social security perspective in a progressive way. For readers from other areas, e.g. citizenship, migration or social policy, we will show how a mobility perspective enriched by a No Border approach can overcome a narrow Western, statist and static perspective on social security. Our goal is to conceptually open up what we call a ‘practical utopia’ research agenda, one that expands our political horizons for future and present socialities.