Are people really conformist-biased? An empirical test and a new mathematical model

According to an influential theory in cultural evolution, within-group similarity of culture is explained by a human 'conformist-bias', which is a hypothesized evolved predisposition to preferentially follow a member of the majority when acquiring ideas and behaviours. However, this notion has little support from social psychological research. In fact, a major theory in social psychology (LATANÉ and WOLF, 1981) argues for what is in effect a ‘nonconformist-bias’: by analogy to standard psychophysics they predict minority sources of influence to have relatively greater impact than majority sources. Here we present a new mathematical model and an experiment on social influence, both specifically designed to test these competing predictions. The results are in line with nonconformism. Finally, we discuss within-group similarity and suggest that it is not a general phenomenon but must be studied trait by trait

Cross-Cultural Differences in Emotional Selection on Transmission of Information

Research on cultural transmission among Americans has established a bias for transmitting stories that have disgusting elements (such as exposure to rats and maggots). Conceived of as a cultural evolutionary force, this phenomenon is one type of emotional selection. In a series of online studies with Americans and Indians we investigate whether there are cultural differences in emotional selection, such that the transmission process favours different kinds of content in different countries. The first study found a bias for disgusting content (rats and maggots) among Americans but not among Indians. Four subsequent studies focused on how country interacts with kind of emotional content (disgusting vs. happy surprises and good news) in reactions to transmission of stories or information. Whereas Indian participants, compared to Americans, tended to be less interested in, and excited by, transmission of stories and news involving common disgust-elicitors (like rats), the opposite pattern held for transmission of happy surprises and good news (e.g., the opening of a new public facility). We discuss various possible explanations and implications

‘Give courage to the ladies’: expansive apprenticeship for women in rural Malawi

Apprenticeship in developed and industrialised nations is increasingly understood as a theory of learning which connects workplace activity and formal study. The concept of ‘expansive apprenticeship’ defines frameworks for workforce development where participants acquire knowledge and skills which will help them in the future as well as in their current roles, whilst ‘restrictive’ apprenticeships limit opportunities for wider, lifelong learning. In developing nations apprenticeship is a traditional route to learning and employment, but apprenticeships in these contexts tend to reflect a restrictive approach characterized by narrowly defined roles and weak educational outcomes. This paper examines a project in Malawi which uses concepts of expansive apprenticeship to address barriers to female continuing education and chronic teacher shortages. The Malawi Access to Teaching Scholarship recruited one thousand women to follow a year-long combined programme of academic distance study and practical work experience in rural primary schools. The aim is to increase the numbers of women teachers in Malawi, especially in rural areas. The Scholarship materials and support structures are designed to move participants from restrictive to expansive contexts for learning so that Scholars develop hybrid roles as students, community workers and apprentice pedagogues. The programme’s resources and approach offer an innovative model of expansive apprenticeship in Sub Saharan Africa

The Impact of HAART on the Respiratory Complications of HIV Infection: Longitudinal Trends in the MACS and WIHS Cohorts

Objective: To review the incidence of respiratory conditions and their effect on mortality in HIV-infected and uninfected individuals prior to and during the era of highly active antiretroviral therapy (HAART). Design: Two large observational cohorts of HIV-infected and HIV-uninfected men (Multicenter AIDS Cohort Study [MACS]) and women (Women's Interagency HIV Study [WIHS]), followed since 1984 and 1994, respectively. Methods: Adjusted odds or hazards ratios for incident respiratory infections or non-infectious respiratory diagnoses, respectively, in HIV-infected compared to HIV-uninfected individuals in both the pre-HAART (MACS only) and HAART eras; and adjusted Cox proportional hazard ratios for mortality in HIV-infected persons with lung disease during the HAART era. Results: Compared to HIV-uninfected participants, HIV-infected individuals had more incident respiratory infections both pre-HAART (MACS, odds ratio [adjusted-OR], 2.4; 95% confidence interval [CI], 2.2-2.7; p<0.001) and after HAART availability (MACS, adjusted-OR, 1.5; 95%CI 1.3-1.7; p<0.001; WIHS adjusted-OR, 2.2; 95%CI 1.8-2.7; p<0.001). Chronic obstructive pulmonary disease was more common in MACS HIV-infected vs. HIV-uninfected participants pre-HAART (hazard ratio [adjusted-HR] 2.9; 95%CI, 1.02-8.4; p = 0.046). After HAART availability, non-infectious lung diseases were not significantly more common in HIV-infected participants in either MACS or WIHS participants. HIV-infected participants in the HAART era with respiratory infections had an increased risk of death compared to those without infections (MACS adjusted-HR, 1.5; 95%CI, 1.3-1.7; p<0.001; WIHS adjusted-HR, 1.9; 95%CI, 1.5-2.4; p<0.001). Conclusion: HIV infection remained a significant risk for infectious respiratory diseases after the introduction of HAART, and infectious respiratory diseases were associated with an increased risk of mortality. © 2013 Gingo et al

Micro-computed tomography of pulmonary fibrosis in mice induced by adenoviral gene transfer of biologically active transforming growth factor-β1

<p>Abstract</p> <p>Background</p> <p>Micro-computed tomography (micro-CT) is a novel tool for monitoring acute and chronic disease states in small laboratory animals. Its value for assessing progressive lung fibrosis in mice has not been reported so far. Here we examined the importance of in vivo micro-CT as non-invasive tool to assess progression of pulmonary fibrosis in mice over time.</p> <p>Methods</p> <p>Pulmonary fibrosis was induced in mice by intratracheal delivery of an adenoviral gene vector encoding biologically active TGF-ß1 (AdTGF-ß1). Respiratory gated and ungated micro-CT scans were performed at 1, 2, 3, and 4 weeks post pulmonary adenoviral gene or control vector delivery, and were then correlated with respective histopathology-based Ashcroft scoring of pulmonary fibrosis in mice. Visual assessment of image quality and consolidation was performed by 3 observers and a semi-automated quantification algorithm was applied to quantify aerated pulmonary volume as an inverse surrogate marker for pulmonary fibrosis.</p> <p>Results</p> <p>We found a significant correlation between classical Ashcroft scoring and micro-CT assessment using both visual assessment and the semi-automated quantification algorithm. Pulmonary fibrosis could be clearly detected in micro-CT, image quality values were higher for respiratory gated exams, although differences were not significant. For assessment of fibrosis no significant difference between respiratory gated and ungated exams was observed.</p> <p>Conclusions</p> <p>Together, we show that micro-CT is a powerful tool to assess pulmonary fibrosis in mice, using both visual assessment and semi-automated quantification algorithms. These data may be important in view of pre-clinical pharmacologic interventions for the treatment of lung fibrosis in small laboratory animals.</p

Evaluation of Current Knowledge, Awareness and Practice of Spirometry among Hospital -based Nigerian Doctors

<p>Abstract</p> <p>Background</p> <p>Spirometry is a cost-effective diagnostic tool for evaluation of lung function and for case-finding in a resource-limited setting. The acceptance of this test depends on the awareness of its indications and the ability to interpret the results. No studies have assessed the knowledge of spirometry among Nigerian doctors. The aim of this study was to evaluate the current knowledge, awareness and practice of spirometry among hospital-based Nigerian doctors.</p> <p>Methods</p> <p>We carried out a cross-sectional survey among 321 doctors working in Nigerian hospitals between March 2008 and June 2008. Information on knowledge, awareness, practice of and barriers to spirometry were obtained using a pre-tested, self-administered structured questionnaire and the data were then analysed.</p> <p>Results</p> <p>Of the 321 doctors that participated, 108 (33.6%) reported that they have good knowledge of spirometry. One hundred and ninety-five (60.7%) were aware of the importance of spirometry in aiding the diagnosis of respiratory diseases; 213(66.4%) were aware of the importance of spirometry in determining the severity of diseases. Medical school was the most common source of knowledge on spirometry (64.5%). Eighty-one (25.2%) doctors reported having a spirometer in their hospitals. Doctors having access to a spirometer used it more frequently for aiding the diagnosis of COPD (40.7% vs.27.5%) and for monitoring of asthma (18.5% vs.11.3%) than those without access to a spirometer. The doctors working in University Teaching Hospitals and Federal Medical Centres (FMC) (22.4% vs. 4.5%) and those having access to a spirometer (40.7 vs.11.3%) were very confident of interpreting spirometry results compared to those working in District and General Hospitals and without access to a spirometer. Irrespective of access to a spirometer or the type of hospital they were employed in, doctors reported that unavailability of a spirometer was the greatest barrier to its use (62.5%) followed by lack of awareness about its usefulness (17.2%).</p> <p>Conclusion</p> <p>The knowledge and practice of spirometry were poor among hospital-based Nigerian doctors because of unavailability of spirometers in most hospitals. These findings have implications for further evaluation, planning and management of patient care in respiratory disease. Spirometers should be made available in all hospitals, and the knowledge of spirometry should be improved among doctors.</p

Is there a uniform approach to the management of diffuse parenchymal lung disease (DPLD) in the UK? A national benchmarking exercise

BACKGROUND: Benchmarking is the comparison of a process to the work or results of others. We conducted a national benchmarking exercise to determine how UK pulmonologists manage common clinical scenarios in diffuse parenchymal lung disease (DPLD), and to determine current use and availability of investigative resources. We compared management decisions to existing international guidelines. METHODS: Consultant members of the British Thoracic Society were mailed a questionnaire seeking their views on the management of three common scenarios in DPLD. They were asked to choose from various management options for each case. Information was also obtained from the respondents on time served as a consultant, type of institution in which they worked and the availability of a local radiologist and histopathologist with an interest/expertise in thoracic medicine. RESULTS: 370 out of 689 consultants replied (54% response rate). There were many differences in the approach to the management of all three cases. Given a scenario of relapsing pulmonary sarcoidosis in a lady with multiple co-morbidities, half of respondents would institute treatment with a variety of immunosuppressants while a half would simply observe. 42% would refer a 57-year old lady with new onset DPLD for a surgical lung biopsy, while a similar number would not. 80% would have referred her for transplantation, but a fifth would not. 50% of consultants from district general hospitals would have opted for a surgical biopsy compared to 24% from cardiothoracic centres: this may reflect greater availability of a radiologist with special interest in thoracic imaging in cardiothoracic centres, obviating the need for tissue diagnosis. Faced with an elderly male with high resolution CT thorax (HRCT) evidence of usual interstitial pneumonia (UIP), three quarters would observe, while a quarter would start immunosuppressants. 11% would refer for a surgical biopsy. 14% of UK pulmonologists responding to the survey revealed they had no access to a radiologist with an interest in thoracic radiology. CONCLUSION: From our survey, it appears there is a lack of consensus in the management of DPLD. This may reflect lack of evidence, lack of resources or a failure to implement current guidelines

Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

BACKGROUND: Exposure to environmental tobacco smoke (ETS), which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies. METHODS: Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing COPD. Participants were recruited from all 48 contiguous U.S. states by random digit dialing. Lifetime ETS exposure was ascertained by structured telephone interview. We used a standard epidemiologic approach to define COPD based on a self-reported physician diagnosis of chronic bronchitis, emphysema, or COPD. RESULTS: Higher cumulative lifetime home and work exposure were associated with a greater risk of COPD. The highest quartile of lifetime home ETS exposure was associated with a greater risk of COPD, controlling for age, sex, race, personal smoking history, educational attainment, marital status, and occupational exposure to vapors, gas, dusts, or fumes during the longest held job (OR 1.55; 95% CI 1.09 to 2.21). The highest quartile of lifetime workplace ETS exposure was also related to a greater risk of COPD (OR 1.36; 95% CI 1.002 to 1.84). The population attributable fraction was 11% for the highest quartile of home ETS exposure and 7% for work exposure. CONCLUSION: ETS exposure may be an important cause of COPD. Consequently, public policies aimed at preventing public smoking may reduce the burden of COPD-related death and disability, both by reducing direct smoking and ETS exposure

Hedgehog signaling via a calcitonin receptor-like receptor can induce arterial differentiation independently of VEGF signaling in zebrafish

Multiple signaling pathways control the specification of endothelial cells (ECs) to become arteries or veins during vertebrate embryogenesis. Current models propose that a cascade of Hedgehog (Hh), vascular endothelial growth factor (VEGF), and Notch signaling acts instructively on ECs to control the choice between arterial or venous fate. Differences in the phenotypes induced by Hh, VEGF, or Notch inhibition suggest that not all of the effects of Hh on arteriovenous specification are mediated by VEGF. We establish that full derepression of the Hh pathway in ptc1;ptc2 mutants converts the posterior cardinal vein into a second arterial vessel that manifests intact arterial gene expression, intersegmental vessel sprouting, and HSC gene expression. Importantly, although VEGF was thought to be absolutely essential for arterial fates, we find that normal and ectopic arterial differentiation can occur without VEGF signaling in ptc1;ptc2 mutants. Furthermore, Hh is able to bypass VEGF to induce arterial differentiation in ECs via the calcitonin receptor-like receptor, thus revealing a surprising complexity in the interplay between Hh and VEGF signaling during arteriovenous specification. Finally, our experiments establish a dual function of Hh during induction of runx1+ HSCs

Non-specific interstitial pneumonia in cigarette smokers: a CT study

The goal of this study was to seek indirect evidence that smoking is an aetiological factor in some patients with non-specific interstitial pneumonia (NSIP). Ten current and eight ex-smokers with NSIP were compared to controls including 137 current smokers with no known interstitial lung disease and 11 non-smokers with NSIP. Prevalence and extent of emphysema in 18 smokers with NSIP were compared with subjects meeting GOLD criteria for chronic obstructive pulmonary disease (COPD; group A; n = 34) and healthy smokers (normal FEV1; group B; n = 103), respectively. Emphysema was present in 14/18 (77.8%) smokers with NSIP. Emphysema did not differ in prevalence between NSIP patients and group A controls (25/34, 73.5%), but was strikingly more prevalent in NSIP patients than in group B controls (18/103, 17.5%, P < 0.0005). On multiple logistic regression, the likelihood of emphysema increased when NSIP was present (OR = 18.8; 95% CI = 5.3–66.3; P < 0.0005) and with increasing age (OR = 1.04; 95% CI = 0.99–1.11; P = 0.08). Emphysema is as prevalent in smokers with NSIP as in smokers with COPD, and is strikingly more prevalent in these two groups than in healthy smoking controls. The association between NSIP and emphysema provides indirect support for a smoking pathogenesis hypothesis in some NSIP patients