Romantic Partnerships and the Dispersion of Social Ties: A Network Analysis of Relationship Status on Facebook

A crucial task in the analysis of on-line social-networking systems is to identify important people --- those linked by strong social ties --- within an individual's network neighborhood. Here we investigate this question for a particular category of strong ties, those involving spouses or romantic partners. We organize our analysis around a basic question: given all the connections among a person's friends, can you recognize his or her romantic partner from the network structure alone? Using data from a large sample of Facebook users, we find that this task can be accomplished with high accuracy, but doing so requires the development of a new measure of tie strength that we term `dispersion' --- the extent to which two people's mutual friends are not themselves well-connected. The results offer methods for identifying types of structurally significant people in on-line applications, and suggest a potential expansion of existing theories of tie strength.Comment: Proc. 17th ACM Conference on Computer Supported Cooperative Work and Social Computing (CSCW), 201

Human-Data Interaction: The Human Face of the Data-Driven Society

The increasing generation and collection of personal data has created a complex ecosystem, often collaborative but sometimes combative, around companies and individuals engaging in the use of these data. We propose that the interactions between these agents warrants a new topic of study: Human-Data Interaction (HDI). In this paper we discuss how HDI sits at the intersection of various disciplines, including computer science, statistics, sociology, psychology and behavioural economics. We expose the challenges that HDI raises, organised into three core themes of legibility, agency and negotiability, and we present the HDI agenda to open up a dialogue amongst interested parties in the personal and big data ecosystems

Testing a model of antecedents and consequences of defensive pessimism and self-handicapping in school physical education

There has been very limited research on the use of self-worth protection strategies in the achievement context of school physical education (PE). Thus, this study aimed to examine some antecedents and consequences of defensive pessimism and self-handicapping. The sample comprised 534 (females n = 275; males n = 259) British pupils recruited from two schools who responded to established questionnaires. Results of structural equation modelling analysis indicated that self-handicapping and defensive pessimism were positively predicted by fear of failure and negatively predicted by competence valuation. In addition, defensive pessimism was negatively predicted by physical self-concept. In turn, defensive pessimism negatively predicted enjoyment in PE and intentions to participate in future optional PE programs. Self-handicapping did not predict enjoyment or intentions. Results from multi-sample structural equation modelling showed the specified model to be largely invariant across males and females. The findings indicate that although both strategies aim to protect one’s self-worth, some of their antecedents and consequences in PE may differ

Early intervention for the management of acute low back pain: A single blind randomised controlled trial of biopsychosocial education, manual therapy and exercise

Design: A single blind randomised controlled trial comparing two models of care for patients with simple acute low back pain (ALBP). Objectives: To compare two research-based models of care for ALBP, and investigate the effect of the timing of physical intervention. Summary of Background Data National guidelines offer conflicting information on the delivery of physical treatment in the management of ALBP. Review of guidelines suggests two different models of care. Direct comparisons between these models are lacking in the literature. The present study aims to compare these two approaches to the management of ALBP. Method: Among 804 referred patients, 102 subjects met the specific admission criteria and were randomly assigned to an ‘assess/advise/treat’ group or an ‘assess/advise/wait’ group. The intervention consisted of biopsychosocial education, manual therapy and exercise. Assessment of short-term outcome enables comparison to be made between intervention and advice to stay active. Assessment of long-term outcome enables comparison to be made between early and late intervention. Study outcomes of reported pain (VAS), functional disability (RMDQ), mood (MZSRDS, MSPQ, STAIS), general health (Euroqol) and quality of life (SF-36) were assessed at baseline, six weeks, three months and six months. Results: At six weeks, the ‘assess/advise/treat’ group demonstrated greater improvements in disability, mood, general health and quality of life than patients in the ‘assess/advise/wait’ group (p0.05). However, mood, general health and quality of life remained significantly better in the ‘assess/advise/treat’ group (p\u3c0.05). Conclusions: At six weeks physiotherapy intervention is more effective than advice on staying active, leading to more rapid improvement in function, mood, quality of life and general health. The timing of intervention affects the progression of psychosocial features. If treatment is provided later, the same psychosocial benefits are not achieved. Therefore an \u27assess/advise/treat\u27 model of care seems to offer better outcomes than an \u27assess/advise/wait\u27 model of care

Exercise intervention in brain injury: a pilot randomized study of Tai Chi Qigong

Objective: To examine the effects of a brief Tai Chi Chuan Qigong (‘Qigong’) exercise intervention on individuals with traumatic brain injury. Design: A single-centre randomized controlled trial pilot study. Setting: A registered charity day centre in the community. Subjects: Twenty individuals with traumatic brain injury. Intervention: Intervention participants attended a Qigong exercise session for one hour per week over eight weeks. Control participants engaged in non-exercise-based social and leisure activities for the same intervention period. Measures: Outcome was assessed at baseline and post intervention using the General Health Questionnaire-12, the Physical Self-Description Questionnaire and the Social Support for Exercise Habits Scale, to measure perceived mood, self-esteem, flexibility, coordination, physical activity and social support. Results: Groups were comparable at baseline. After the intervention, mood was improved in the exercise group when compared with controls (U ¼ 22.0, P ¼ 0.02). Improvements in self-esteem (Z ¼ 2.397, P ¼ 0.01) and mood (Z ¼ –2.032, P ¼ 0.04) across the study period were also evident in the exercise group only. There were no significant differences in physical functioning between groups. In view of the sample size, these findings are inconclusive. Conclusions: This study provides preliminary evidence that a brief Qigong exercise intervention programme may improve mood and self-esteem for individuals with traumatic brain injury. This needs to be tested in a large-scale randomized trial

The reliability of eyetracking to assess attentional bias to threatening words in healthy individuals

Eyetracking is commonly used to investigate attentional bias. Although some studies have investigated the internal consistency of eyetracking, data are scarce on the test–retest reliability and agreement of eyetracking to investigate attentional bias. This study reports the test–retest reliability, measurement error, and internal consistency of 12 commonly used outcome measures thought to reflect the different components of attentional bias: overall attention, early attention, and late attention. Healthy participants completed a preferential-looking eyetracking task that involved the presentation of threatening (sensory words, general threat words, and affective words) and nonthreatening words. We used intraclass correlation coefficients (ICCs) to measure test–retest reliability (ICC \u3e .70 indicates adequate reliability). The ICCs(2, 1) ranged from –.31to.71. Reliability varied according to the outcome measure and threat word category. Sensory words had a lower mean ICC (.08) than either affective words (.32) or general threat words (.29). A longer exposure time was associated with higher test–retest reliability. All of the outcome measures, except second-run dwell time, demonstrated low measurement error (\u3c6%). Most of the outcome measures reported high internal consistency (α \u3e.93). Recommendations are discussed for improving the reliability of eyetracking tasks in future research

Experiences of living with chronic back pain: The physical disabilities

Purpose. Back-related functional limitations are largely assessed using lists of activities, each scored on a yes/no basis and the scores then summed. This provides little information about how chronic back pain (CBP) patients live with their condition. This study describes the consequences of living day-to-day with CBP and documents the 'insider' accounts of its impact on daily life. Method. Unstructured interviews, using the 'Framework' approach with topic guide, were recorded and transcribed verbatim. Subjects were sampled for age, sex, ethnicity and occupation from new referrals with back pain to a rheumatology outpatient clinic. Eleven subjects (5 male, 6 female) were interviewed either in English (n = 9) or their preferred language (n = 2). Interviews were read in-depth twice to identify the topics. Data were extracted in phrases and sentences using thematic content analysis. Results. Four themes emerged: sleep/rest, mobility, independence and leisure. All subjects reported issues about sleep and rest, nine about mobility, seven about independence and six on leisure. Most descriptions concerned loss and limitation in daily life. Strategies for coping with sleep disruption and physical limitations were described. Conclusions. Subjects provided graphic 'in-depth' descriptions of experiences living with CBP every day; expressed regret at the loss of capabilities and distress at the functional consequences of those losses. Facilitating 'adjustment' to 'loss' may be more helpful than inferring the potential for a life free of pain as a result of therapeutic endeavours

Levosimendan for the prevention of acute organ dysfunction in sepsis

BACKGROUND Levosimendan is a calcium-sensitizing drug with inotropic and other properties that may improve outcomes in patients with sepsis. METHODS We conducted a double-blind, randomized clinical trial to investigate whether levosimendan reduces the severity of organ dysfunction in adults with sepsis. Patients were randomly assigned to receive a blinded infusion of levosimendan (at a dose of 0.05 to 0.2 μg per kilogram of body weight per minute) for 24 hours or placebo in addition to standard care. The primary outcome was the mean daily Sequential Organ Failure Assessment (SOFA) score in the intensive care unit up to day 28 (scores for each of five systems range from 0 to 4, with higher scores indicating more severe dysfunction; maximum score, 20). Secondary outcomes included 28-day mortality, time to weaning from mechanical ventilation, and adverse events. RESULTS The trial recruited 516 patients; 259 were assigned to receive levosimendan and 257 to receive placebo. There was no significant difference in the mean (±SD) SOFA score between the levosimendan group and the placebo group (6.68±3.96 vs. 6.06±3.89; mean difference, 0.61; 95% confidence interval [CI], −0.07 to 1.29; P=0.053). Mortality at 28 days was 34.5% in the levosimendan group and 30.9% in the placebo group (absolute difference, 3.6 percentage points; 95% CI, −4.5 to 11.7; P=0.43). Among patients requiring ventilation at baseline, those in the levosimendan group were less likely than those in the placebo group to be successfully weaned from mechanical ventilation over the period of 28 days (hazard ratio, 0.77; 95% CI, 0.60 to 0.97; P=0.03). More patients in the levosimendan group than in the placebo group had supraventricular tachyarrhythmia (3.1% vs. 0.4%; absolute difference, 2.7 percentage points; 95% CI, 0.1 to 5.3; P=0.04). CONCLUSIONS The addition of levosimendan to standard treatment in adults with sepsis was not associated with less severe organ dysfunction or lower mortality. Levosimendan was associated with a lower likelihood of successful weaning from mechanical ventilation and a higher risk of supraventricular tachyarrhythmia. (Funded by the NIHR Efficacy and Mechanism Evaluation Programme and others; LeoPARDS Current Controlled Trials number, ISRCTN12776039.

Recovery of West Nile Virus Envelope Protein Domain III Chimeras with Altered Antigenicity and Mouse Virulence

ABSTRACT Flaviviruses are positive-sense, single-stranded RNA viruses responsible for millions of human infections annually. The envelope (E) protein of flaviviruses comprises three structural domains, of which domain III (EIII) represents a discrete subunit. The EIII gene sequence typically encodes epitopes recognized by virus-specific, potently neutralizing antibodies, and EIII is believed to play a major role in receptor binding. In order to assess potential interactions between EIII and the remainder of the E protein and to assess the effects of EIII sequence substitutions on the antigenicity, growth, and virulence of a representative flavivirus, chimeric viruses were generated using the West Nile virus (WNV) infectious clone, into which EIIIs from nine flaviviruses with various levels of genetic diversity from WNV were substituted. Of the constructs tested, chimeras containing EIIIs from Koutango virus (KOUV), Japanese encephalitis virus (JEV), St. Louis encephalitis virus (SLEV), and Bagaza virus (BAGV) were successfully recovered. Characterization of the chimeras in vitro and in vivo revealed differences in growth and virulence between the viruses, with in vivo pathogenesis often not being correlated with in vitro growth. Taken together, the data demonstrate that substitutions of EIII can allow the generation of viable chimeric viruses with significantly altered antigenicity and virulence. IMPORTANCE The envelope (E) glycoprotein is the major protein present on the surface of flavivirus virions and is responsible for mediating virus binding and entry into target cells. Several viable West Nile virus (WNV) variants with chimeric E proteins in which the putative receptor-binding domain (EIII) sequences of other mosquito-borne flaviviruses were substituted in place of the WNV EIII were recovered, although the substitution of several more divergent EIII sequences was not tolerated. The differences in virulence and tissue tropism observed with the chimeric viruses indicate a significant role for this sequence in determining the pathogenesis of the virus within the mammalian host. Our studies demonstrate that these chimeras are viable and suggest that such recombinant viruses may be useful for investigation of domain-specific antibody responses and the more extensive definition of the contributions of EIII to the tropism and pathogenesis of WNV or other flaviviruses