A case–control study relating railroad worker mortality to diesel exhaust exposure using a threshold regression model

A case–control study of lung cancer mortality in U.S. railroad workers in jobs with and without diesel exhaust exposure is reanalyzed using a new threshold regression methodology. The study included 1256 workers who died of lung cancer and 2385 controls who died primarily of circulatory system diseases. Diesel exhaust exposure was assessed using railroad job history from the US Railroad Retirement Board and an industrial hygiene survey. Smoking habits were available from next-of-kin and potential asbestos exposure was assessed by job history review. The new analysis reassesses lung cancer mortality and examines circulatory system disease mortality. Jobs with regular exposure to diesel exhaust had a survival pattern characterized by an initial delay in mortality, followed by a rapid deterioration of health prior to death. The pattern is seen in subjects dying of lung cancer, circulatory system diseases, and other causes. The unique pattern is illustrated using a new type of Kaplan–Meier survival plot in which the time scale represents a measure of disease progression rather than calendar time. The disease progression scale accounts for a healthy-worker effect when describing the effects of cumulative exposures on mortality.     

Multigaussian models: The danger of parsimony

Summary MultiGaussian models have the intrinsic property of imposing very little continuity to extreme values. If the variable that is being modeled is hydraulic conductivity and the processes being studied are groundwater flow and mass transport, the absence of continuous paths of extreme values will have a retardation effect in the computed travel times. In the case of radionuclide release of nuclear waste from a deep geological repository, underestimation of travel times may lead to unsafe decision making. To demonstrate the impact of the low continuity of extreme value implicit to multiGaussian modes, travel times are computed in a site similar to Finnsj?n-one of the sites in crystaline rock studied in Sweden-using two stochastic models with the same histogram and covariance, one of them is multiGaussian, and the other is not and displays high connectivity of extreme high values. The results show that the multiGaussian model leads to less conservative results than the non-multiGaussian one. Invoking the parisimony principle to select a multiGaussian model as the simplest model that can be fully described by a mean value and a covariance function should not be justification enough for such selection. If there is not enough data to characterize the connectivity of the extreme values and therefore distriminate whether a multiGaussian model is appropriate or not, less parismonious models must also be considered.     

Social movement schools: sites for consciousness transformation,training, and prefigurative social development

ABSTRACT

We develop the concept of “social movement school’ (SMS), showing how these organizational spaces are deliberately designed for purposes of educating, mentoring, training, and coordinating individuals as effective, committed movement agents. SMSs can also be important sites of prefigurative design and practice for future societal development consistent with movement goals. We motivate the theoretical significance of SMSs based on five perspectives in social movement scholarship: (1) resource mobilization; (2) cultural approaches to repertoires of contention; (3) cognitive perspective; (4) micro-mobilization; and (5) biographical consequences of participation. We then offer a typology to capture primary purposes, and spatial reach within the broad field of SMSs. Within-movement variation is illustrated by focusing on a variety of SMSs in the U.S. civil rights movement; and the cross-movement breadth of the concept is illustrated by highlighting contemporary SMS forms drawn from three very different movements–labor, radical feminism, and mindfulness meditation movements. In the interest of launching a research agenda on SMSs, we end with several key questions that could serve to guide future research. Important theoretical, empirical, and practical considerations suggest that SMSs deserve the attention of scholars and activists alike.     

Search for optimal designs in a three stagenested random model

In this paper we define a class of unbalanced designs, denoted by C_k,s,t, for estimating the components of variance in a k-stage nested random effects linear model. This class contains many of the designs proposed in the literature for nested components of variance models. We focus on the three-state model and discuss the determination of locally optimal designs within this class using a systematic computer search. For large sample sizes we show that approximate optimal designs may be obtained using a limit argument combined with numerical optimization. A comparison of our designs with previously published designs suggests that, in many cases, our designs result in substantial gains in efficiency.     

Real-life closeness of social media contacts and depressive symptoms among university students

ABSTRACT

Objective: To examine the association between degree of real-life closeness of social media (SM) contacts and depressive symptoms. Participants: Students ages 18–30 (N = 1124) were recruited in August 2016. Methods: Participants completed an online survey assessing SM use and depression. We used multivariable logistic regression to assess associations between real-life closeness of SM contacts and depressive symptoms. Results: After controlling for covariates, each 10% increase in the proportion of SM friends with whom participants had no face-to-face relationship was associated with a 9% increase in odds of depressive symptoms (AOR = 1.09; 95% CI = 1.05–1.13). However, each 10% increase in the proportion of SM friends with whom participants had a close face-to-face relationship was associated with a 7% decrease in depressive symptoms (AOR = 0.93; 95% CI = 0.89–0.97). Conclusions: Having no in-person relationship with SM contacts is associated with increased depressive symptoms; however, having close in-person relationships with SM contacts is associated with decreased depressive symptoms.     

Victim or Whore: The Similarities and Differences between Victim's Experiences of Domestic Violence and Sex Trafficking

This research review addresses the similarities and differences between domestic violence and sex trafficking victimization. While there is evidence that domestic violence and sex trafficking often co-occur, there is a large disparity in the understanding and interventions utilized by law enforcement as well as the services available for victims of each crime despite the considerable overlap of victimization. This article explores current research regarding domestic violence and sex trafficking with a focus towards identifying areas of overlap and areas distinct to sex trafficking.     

Problems with Traditional Science Publishing and Finding a Wider Niche for Post-Publication Peer Review

Science affects multiple basic sectors of society. Therefore, the findings made in science impact what takes place at a commercial level. More specifically, errors in the literature, incorrect findings, fraudulent data, poorly written scientific reports, or studies that cannot be reproduced not only serve as a burden on tax-payers’ money, but they also serve to diminish public trust in science and its findings. Therefore, there is every need to fortify the validity of data that exists in the science literature, not only to build trust among peers, and to sustain that trust, but to reestablish trust in the public and private academic sectors that are witnessing a veritable battle-ground in the world of science publishing, in some ways spurred by the rapid evolution of the open access (OA) movement. Even though many science journals, traditional and OA, claim to be peer reviewed, the truth is that different levels of peer review occur, and in some cases no, insufficient, or pseudo-peer review takes place. This ultimately leads to the erosion of quality and importance of science, allowing essentially anything to become published, provided that an outlet can be found. In some cases, predatory OA journals serve this purpose, allowing papers to be published, often without any peer review or quality control. In the light of an explosion of such cases in predatory OA publishing, and in severe inefficiencies and possible bias in the peer review of even respectable science journals, as evidenced by the increasing attention given to retractions, there is an urgent need to reform the way in which authors, editors, and publishers conduct the first line of quality control, the peer review. One way to address the problem is through post-publication peer review (PPPR), an efficient complement to traditional peer-review that allows for the continuous improvement and strengthening of the quality of science publishing. PPPR may also serve as a way to renew trust in scientific findings by correcting the literature. This article explores what is broadly being said about PPPR in the literature, so as to establish awareness and a possible first-tier prototype for the sciences for which such a system is undeveloped or weak.     

Looking Behavior and Smiling in Down Syndrome Infants

We studied the relation between direction of gaze and smiling in 15 typically developing infants and 15 infants with Down syndrome. All of them were videotaped during face-to-face interaction with their mothers at home, and while having access to their familiar toys. Results showed that mothers in the two groups behaved in a similar way; that Down syndrome infants looked at their mother's face for longer than typically developing children; and that the relationship between looking and smiling was similar in the two cases and reflected as an increase in the time the infant looked at its mother's face and a decrease in the time the infant looked at toys. It was deduced that Down syndrome infants are capable of distinguishing the differential significance of faces and toys, so that, in the same way as typically developing infants, they direct their affective behavior fundamentally towards the social element, which leads us to consider the affiliative function implied by this expression.     

Mechanization in building construction projects: assessment and views from the practitioners

Abstract

While mechanization has been widely adopted in the current construction industry, little research has been done to assess the level of mechanization in building construction projects. The aims of this study are to propose a framework that can assess the level of mechanization in building construction projects, to develop a computer-based tool that can help assess mechanization levels, and to collect the views of industry practitioners regarding mechanization. To achieve these goals, a comprehensive literature review was conducted first, and based on which a six-layer assessment framework, namely Mechanization Index for Building Construction Projects, was proposed. After that, Mechanization Index Assessment Tool, a computer-based tool that can assess the level of mechanization in building construction projects, was developed. The developed tool was adopted in 14 construction projects in Singapore. Assessment results showed that the mechanization level of the projects was 48.54 percent out of 100, which is moderate. Results also reported that ‘site preparation’ and ‘underground piping’ were two work types that are more mechanized, while work types of ‘formwork’, ‘tiling’, and ‘painting’ were relatively less mechanized. Additionally, industry practitioners perceived that the mechanization levels in the current building construction projects and industry were moderate and more efforts should be put in this regard, especially from the perspective of the industry. This study is the first piece of research work that assesses the level of mechanization in building construction projects and thus, it contributes to the body of knowledge. Furthermore, the assessment tool developed can easily be used either by industry practitioners or by construction authorities to do mechanization assessment. Thus, this study contributes to the practice as well.     

A Preliminary Investigation of Risks for Adverse Outcomes of Relationship Seeking on Social Network Sites (SNS): A Descriptive Study of Women Over 50 Seeking Relationships on MySpace in Hillsborough County,Florida

In contrast to younger populations, little attention has been paid to the increase in seniors using Internet-based venues to find relationships and the potential risk for adverse outcomes this poses. This study examined data collected via an online survey from 45 ethnically diverse women aged 50+ “seeking relationships” on MySpace. The majority of women reported a relationship with someone they met online (85%). They also reported experiencing adverse events including financial exploitation (40%), threats (55%), and physical harm (38%) by someone they met online at levels greater than traditional relationship seeking in the general population. Directions for future research are explored.