A dimension-breaking phenomenon for water waves with weak surface tension

It is well known that the water-wave problem with weak surface tension has small-amplitude line solitary-wave solutions which to leading order are described by the nonlinear Schr\"odinger equation. The present paper contains an existence theory for three-dimensional periodically modulated solitary-wave solutions which have a solitary-wave profile in the direction of propagation and are periodic in the transverse direction; they emanate from the line solitary waves in a dimension-breaking bifurcation. In addition, it is shown that the line solitary waves are linearly unstable to long-wavelength transverse perturbations. The key to these results is a formulation of the water wave problem as an evolutionary system in which the transverse horizontal variable plays the role of time, a careful study of the purely imaginary spectrum of the operator obtained by linearising the evolutionary system at a line solitary wave, and an application of an infinite-dimensional version of the classical Lyapunov centre theorem.Comment: The final publication is available at Springer via http://dx.doi.org/10.1007/s00205-015-0941-

Father Involvements Influence on Mother\u27s Perceptions of Parenting in an Appalachian Sample

Father involvement in parenting can have a positive influence on both children and mothers. During times of economic stress it may also add to the resources available and make a positive contribution to mothers parenting practices. In this study it was considered how father involvement may influence mother\u27s perceptions of parenting. Specifically, this study looks at father involvement in an Appalachian sample. Five participants completed questionnaires which answered questions about mothers\u27 present perceptions of parenting and father involvement. No significant associations were found between father involvement and mother\u27s perceptions of parenting. Limitations include small sample size and a lack of diversity in the sample. Possibilities for future research include cultural inclusion and qualitative questionnaires as well. Limitations and additional possibilities for future research are discussed in greater detail within the study

Cerebral activations related to ballistic, stepwise interrupted and gradually modulated movements in parkinson patients

Patients with Parkinson's disease (PD) experience impaired initiation and inhibition of movements such as difficulty to start/stop walking. At single-joint level this is accompanied by reduced inhibition of antagonist muscle activity. While normal basal ganglia (BG) contributions to motor control include selecting appropriate muscles by inhibiting others, it is unclear how PD-related changes in BG function cause impaired movement initiation and inhibition at single-joint level. To further elucidate these changes we studied 4 right-hand movement tasks with fMRI, by dissociating activations related to abrupt movement initiation, inhibition and gradual movement modulation. Initiation and inhibition were inferred from ballistic and stepwise interrupted movement, respectively, while smooth wrist circumduction enabled the assessment of gradually modulated movement. Task-related activations were compared between PD patients (N = 12) and healthy subjects (N = 18). In healthy subjects, movement initiation was characterized by antero-ventral striatum, substantia nigra (SN) and premotor activations while inhibition was dominated by subthalamic nucleus (STN) and pallidal activations, in line with the known role of these areas in simple movement. Gradual movement mainly involved antero-dorsal putamen and pallidum. Compared to healthy subjects, patients showed reduced striatal/SN and increased pallidal activation for initiation, whereas for inhibition STN activation was reduced and striatal-thalamo-cortical activation increased. For gradual movement patients showed reduced pallidal and increased thalamo-cortical activation. We conclude that PD-related changes during movement initiation fit the (rather static) model of alterations in direct and indirect BG pathways. Reduced STN activation and regional cortical increased activation in PD during inhibition and gradual movement modulation are better explained by a dynamic model that also takes into account enhanced responsiveness to external stimuli in this disease and the effects of hyper-fluctuating cortical inputs to the striatum and STN in particular

The Cultural Production of Health Inequalities: A Cross-Sectional, Multilevel Examination of 52 Countries

In a 2001 report, the U.S. National Institutes of Health called for more integration of the social sciences into health-related research, including research guided by theories and methods that take social and cultural systems into consideration. Based on a theoretical framework that integrates Hofstede\u27s cultural dimensions with sociological theory, the authors used multilevel modeling to explore the association of culture with structural inequality and health disparities. Their results support the idea that cultural dimensions and social structure, along with economic development, may account for much of the cross-national variation in the distribution of health inequalities. Sensitivity tests also suggest that an interaction between culture and social structure may confound the relationship between income inequality and health. It is necessary to identify important cultural and social structural characteristics before we can achieve an understanding of the complex, dynamic systems that affect health, and develop culturally sensitive interventions and policies. This study takes a step toward identifying some of the relevant cultural and structural influences. More research is needed to explore the pathways leading from the sociocultural environment to health inequalities

Labor markets and health:An integrated life course perspective

Current work and health research is fragmented, focusing on jobs, exposures, specific worker groups, work organization, or employment contracts. An emphasis on the labor market in framing the work and health relationship conceptualizes work not only as an exposure that increases or lessens health risk but also as a life course experience that is dependent on place and time. The intention is to illustrate how the labor markets and health framework coupled with a life course perspective extends other epidemiological approaches to work and health to identify new research questions. Taking the changing nature of work and labor markets into account, this paper updates the labor markets and health framework. It then reviews, defines, and integrates key life course concepts. A model is developed that guides the understanding of how labor markets and health trajectories emerge from the consideration of the working life course in a social context. The application leads to new research questions investigating characteristics of labor markets and health trajectories that may lead to positive health outcomes over the life course

Work functioning of Dutch workers with a chronic disease in early, mid and late working life:Cross-sectional findings from 38,470 participants in the Lifelines Cohort Study

Insight into the work functioning of workers with chronic diseases may help to improve their sustainable employability. This study examines the work functioning of workers with cardiovascular disease (CVD), diabetes mellitus type 2 (DM2), chronic obstructive pulmonary disease (COPD), rheumatoid arthritis and depression across early, mid, and late working life. This cross-sectional study used data from 38,470 participants of the Dutch Lifelines study. Chronic diseases were classified based on clinical measures, self-reports, and medication. Work functioning was measured with the Work Role Functioning Questionnaire (WRFQ), covering work scheduling and output demands, physical demands, mental and social demands, and flexibility demands. Multivariable linear and logistic regression analyses were used to examine associations between chronic diseases and work functioning (continuous) and low work functioning (dichotomous). Depression was associated with lower work functioning across all subscales and working life stages, with the lowest score in the work scheduling and output demands subscale in late working life (B:-9.51;95%CI:-11.4,-7.65). Rheumatoid arthritis was most strongly associated with lower work functioning in the physical demands subscale, with the lowest score in early working life (B:-9.97;95%CI:-19.0,-0.89). Associations between CVD and DM2 and work functioning were absent in early working life but present in mid and late working life. Associations between COPD and work functioning were absent in mid working life but present in late working life. Occupational health professionals could use the WRFQ to identify workers' perceived difficulties in meeting specific work demands, pointing out directions for interventions to mitigate perceived difficulties and thereby improve sustainable employability.</p

Investigating young adults' mental health and early working life trajectories from a life course perspective:the role of transitions

BACKGROUND: Many young adults leave the labour market because of mental health problems or never really enter it, through early moves onto disability benefits. Across many countries of the Organisation for Economic Co-operation and Development, between 30% and 50% of all new disability benefit claims are due to mental health problems; among young adults this moves up to 50%-80%. OUTLINE: We propose a research agenda focused on transitions in building young adults' mental health and early working life trajectories, considering varying views for subgroups of a society. First, we briefly review five transition characteristics, then we elaborate a research agenda with specific research questions. RESEARCH AGENDA: Our research agenda focuses on transitions as processes, in time and place and as sensitive periods, when examining young adults' mental health and early working life trajectories from a life course perspective. As more and more childhood and adolescent cohorts mature and facilitate research on later life labour market, work and health outcomes, transition research can help guide policy and practice interventions. FUTURE CROSS-DISCIPLINARY RESEARCH: In view of the many challenges young adults face when entering the changing world of work and labour markets, future research on transitions in young adults related to their mental health and early working life trajectories will provide ample opportunities for collaborative cross-disciplinary research and stimulate debate on this important challenge

Vision Screening in Children Aged 6 Months to 5 Years: Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance: Preschool vision screening could allow detection and treatment of vision abnormalities during a critical developmental stage, preserving function and quality of life. Objective: To review the evidence on screening for and treatment of amblyopia, its risk factors, and refractive error in children aged 6 months to 5 years to inform the US Preventive Services Task Force. Data Sources: MEDLINE, Cochrane Library, CINAHL, and trial registries through June 2016; references; and experts, with surveillance of the literature through June 7, 2017. Study Selection: English-language randomized clinical trials (RCTs) or prospective cohort studies that evaluated screening, studies evaluating test accuracy, RCTs of treatment vs inactive controls, and cohort studies or case-control studies assessing harms. Data Extraction and Synthesis: Dual review of abstracts, full-text articles, and study quality; qualitative synthesis of findings. Studies were not quantitatively pooled because of clinical and methodological heterogeneity. Main Outcomes and Measures: Visual acuity, amblyopia, school performance, functioning, quality of life, test accuracy, testability, and harms. Results: Forty studies were included (N = 34 709); 34 evaluated test accuracy. No RCTs compared screening with no screening, and no studies evaluated school performance, function, or quality of life. Studies directly assessing earlier or more intensive screening were limited by high attrition. Positive likelihood ratios were between 5 and 10 for amblyopia risk factors or nonamblyogenic refractive error in most studies of test accuracy and were greater than 10 in most studies evaluating combinations of clinical tests. Inability to cooperate may limit use of some tests in children younger than 3 years. Studies with low prevalence (75%). Among children with amblyopia risk factors (eg, strabismus or anisometropia), patching improved visual acuity of the amblyopic eye by a mean of less than 1 line on a standard chart after 5 to 12 weeks for children pretreated with glasses (2 RCTs, 240 participants); more children treated with patching than with no patching experienced improvement of at least 2 lines (45% vs 21%; P = .003; 1 RCT, 180 participants). Patching plus glasses improved visual acuity by about 1 line after 1 year (0.11 logMAR [95% CI, 0.05-0.17]) for children not pretreated with glasses (1 RCT, 177 participants). Glasses alone improved visual acuity by less than 1 line after 1 year (0.08 logMAR [95% CI, 0.02-0.15], 1 RCT, 177 participants). Conclusions and Relevance: Studies directly evaluating the effectiveness of screening were limited and do not establish whether vision screening in preschool children is better than no screening. Indirect evidence supports the utility of multiple screening tests for identifying preschool children at higher risk for vision problems and the effectiveness of some treatments for improving visual acuity outcomes