A 3D-CTM with detailed online PSC-microphysics: analysis of the Antarctic winter 2003 by comparison with satellite observations

International audienceWe present the first detailed microphysical simulations which are performed online within the framework of a global 3-D chemical transport model (CTM) with full chemistry. The model describes the formation and evolution of four types of polar stratospheric cloud (PSC) particles. Aerosol freezing and other relevant microphysical processes are treated in a full explicit way. Each particle type is described by a binned size distribution for the number density and chemical composition. This set-up allows for an accurate treatment of sedimentation and for detailed calculation of surface area densities and optical properties. Simulations are presented for the Antarctic winter of 2003 and comparisons are made to a diverse set of satellite observations (optical and chemical measurements of POAM III and MIPAS) to illustrate the capabilities of the model. This study shows that a combined resolution approach where microphysical processes are simulated in coarse-grained conditions gives good results for PSC formation and its large-scale effect on the chemical environment through processes such as denitrification, dehydration and ozone loss. It is also shown that the influence of microphysical parameters can be measured directly from these processes

Classifying evolutionary forces in language change using neural networks

A fundamental problem in research into language and cultural change is the difficulty of distinguishing processes of stochastic drift (also known as neutral evolution) from processes that are subject to selection pressures. In this article, we describe a new technique based on deep neural networks, in which we reformulate the detection of evolutionary forces in cultural change as a binary classification task. Using residual networks for time series trained on artificially generated samples of cultural change, we demonstrate that this technique is able to efficiently, accurately and consistently learn which aspects of the time series are distinctive for drift and selection, respectively. We compare the model with a recently proposed statistical test, the Frequency Increment Test, and show that the neural time series classification system provides a possible solution to some of the key problems associated with this test.Language Use in Past and Presen

Initial high anti-emetic efficacy of granisetron with dexamethasone is not maintained over repeated cycles.

We have reported previously that the anti-emetic efficacy of single agent 5HT3 antagonists is not maintained when analysed with the measurement of cumulative probabilities. Presently, the most effective anti-emetic regimen is a combination of a 5HT3 antagonist plus dexamethasone. We, therefore, assessed the sustainment of efficacy of such a combination in 125 patients, scheduled to receive cisplatin > or = 70 mg m(-2) either alone or in combination with other cytotoxic drugs. Anti-emetic therapy was initiated with 10 mg of dexamethasone and 3 mg of granisetron intravenously, before cisplatin. On days 1-6, patients received 8 mg of dexamethasone and 1 mg of granisetron twice daily by oral administration. Protection was assessed during all cycles and calculated based on cumulative probability analyses using the method of Kaplan-Meier and a model for transitional probabilities. Irrespective of the type of analysis used, the anti-emetic efficacy of granisetron/dexamethasone decreased over cycles. The initial complete acute emesis protection rate of 66% decreased to 30% according to the method of Kaplan-Meier and to 39% using the model for transitional probabilities. For delayed emesis, the initial complete protection rate of 52% decreased to 21% (Kaplan-Meier) and to 43% (transitional probabilities). In addition, we observed that protection failure in the delayed emesis period adversely influenced the acute emesis protection in the next cycle. We conclude that the anti-emetic efficacy of a 5HT3 antagonist plus dexamethasone is not maintained over multiple cycles of highly emetogenic chemotherapy, and that the acute emesis protection is adversely influenced by protection failure in the delayed emesis phase

Miscellanea Herpetologica Gabonica XVI

peer reviewe

Nurse moral disengagement

Background: Ethics is a founding component of the nursing profession; however, nurses sometimes find it difficult to constantly adhere to the required ethical standards. There is limited knowledge about the factors that cause a committed nurse to violate standards; moral disengagement, originally developed by Bandura, is an essential variable to consider. Research objectives: This study aimed at developing and validating a nursing moral disengagement scale and investigated how moral disengagement is associated with counterproductive and citizenship behaviour at work. Research design: The research comprised a qualitative study and a quantitative study, combining a crossvalidation approach and a structural equation model. Participants and research context: A total of 60 Italian nurses (63% female) involved in clinical work and enrolled as students in a postgraduate master’s programme took part in the qualitative study. In 2012, the researchers recruited 434 nurses (76% female) from different Italian hospitals using a convenience sampling method to take part in the quantitative study. Ethical considerations: All the organisations involved and the university gave ethical approval; all respondents participated on a voluntary basis and did not receive any form of compensation. Findings: The nursing moral disengagement scale comprised a total of 22 items. Results attested the mono-dimensionality of the scale and its good psychometric properties. In addition, results highlighted a significant association between moral disengagement and both counterproductive and citizenship behaviours

Psychometric Evaluation of the HIV Stigma Scale in a Swedish Context

Background HIV-related stigma has negative consequences for infected people's lives and is a barrier to HIV prevention. Therefore valid and reliable instruments to measure stigma are needed to enable mapping of HIV stigma. This study aimed to evaluate the psychometric properties of the HIV stigma scale in a Swedish context with regard to construct validity, data quality, and reliability. Methods The HIV stigma scale, developed by Berger, Ferrans, and Lashley (2001), was distributed to a cross-sectional sample of people living with HIV in Sweden (n = 194). The psychometric evaluation included exploratory factor analysis together with an analysis of the distribution of scores, convergent validity by correlations between the HIV stigma scale and measures of emotional well-being, and an analysis of missing items and floor and ceiling effects. Reliability was assessed using Cronbach's α. Results The exploratory factor analysis suggested a four-factor solution, similar to the original scale, with the dimensions personalised stigma, disclosure concerns, negative self-image, and concerns with public attitudes. One item had unacceptably low loadings and was excluded. Correlations between stigma dimensions and emotional well-being were all in the expected direction and ranged between −0.494 and −0.210. The instrument generated data of acceptable quality except for participants who had not disclosed their HIV status to anybody. In line with the original scale, all subscales demonstrated acceptable internal consistency with Cronbach's α 0.87–0.96. Conclusion A 39-item version of the HIV stigma scale used in a Swedish context showed satisfactory construct validity and reliability. Response alternatives are suggested to be slightly revised for items assuming the disclosure of diagnosis to another person. We recommend that people that have not disclosed should skip all questions belonging to the dimension personalised stigma. Our analysis confirmed construct validity of the instrument even without this dimension

EXPLICIT: a feasibility study of remote expert elicitation in health technology assessment

This is the final version of the article. Available from BioMed Central via the DOI in this recordBACKGROUND: Expert opinion is often sought to complement available information needed to inform model-based economic evaluations in health technology assessments. In this context, we define expert elicitation as the process of encoding expert opinion on a quantity of interest, together with associated uncertainty, as a probability distribution. When availability for face-to-face expert elicitation with a facilitator is limited, elicitation can be conducted remotely, overcoming challenges of finding an appropriate time to meet the expert and allowing access to experts situated too far away for practical face-to-face sessions. However, distance elicitation is associated with reduced response rates and limited assistance for the expert during the elicitation session. The aim of this study was to inform the development of a remote elicitation tool by exploring the influence of mode of elicitation on elicited beliefs. METHODS: An Excel-based tool (EXPLICIT) was developed to assist the elicitation session, including the preparation of the expert and recording of their responses. General practitioners (GPs) were invited to provide expert opinion about population alcohol consumption behaviours. They were randomised to complete the elicitation by either a face-to-face meeting or email. EXPLICIT was used in the elicitation sessions for both arms. RESULTS: Fifteen GPs completed the elicitation session. Those conducted by email were longer than the face-to-face sessions (13 min 30 s vs 10 min 26 s, p = 0.1) and the email-elicited estimates contained less uncertainty. However, the resulting aggregated distributions were comparable. CONCLUSIONS: EXPLICIT was useful in both facilitating the elicitation task and in obtaining expert opinion from experts via email. The findings support the opinion that remote, self-administered elicitation is a viable approach within the constraints of HTA to inform policy making, although poor response rates may be observed and additional time for individual sessions may be required.This paper presents independent research funded by the National Institute of Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) for the South West Peninsula

Exercise and Physical Therapy Interventions for Children with Ataxia: a systematic review

The effectiveness of exercise and physical therapy for children with ataxia is poorly understood. The aim of this systematic review was to critically evaluate the range, scope and methodological quality of studies investigating the effectiveness of exercise and physical therapy interventions for children with ataxia. The following databases were searched: AMED, CENTRAL, CDSR, CINAHL, ClinicalTrials.gov, EMBASE, Ovid MEDLINE, PEDro and Web of Science. No limits were placed on language, type of study or year of publication. Two reviewers independently determined whether the studies met the inclusion criteria, extracted all relevant outcomes, and conducted methodological quality assessments. A total of 1988 studies were identified, and 124 full texts were screened. Twenty studies were included in the review. A total of 40 children (aged 5-18 years) with ataxia as a primary impairment participated in the included studies. Data were able to be extracted from eleven studies with a total of 21 children (aged 5-18 years), with a range of cerebellar pathology. The studies reported promising results but were of low methodological quality (no RCTs), used small sample sizes and were heterogeneous in terms of interventions, participants and outcomes. No firm conclusions can be made about the effectiveness of exercise and physical therapy for children with ataxia. There is a need for further high-quality child-centred research

What does 'acceptance' mean? Public reflections on the idea that addiction is a brain disease

Public responses to the dissemination of neuroscientific explanations of addiction and other mental disorders are an interesting sociocultural phenomenon. We investigated how 55 members of the Australian public deliberated on the idea that 'addiction is a brain disease'. Our findings point to the diverse ways in which the public understands and utilises this proposition. Interviewees readily accepted that drugs affect brain functioning but were ambivalent about whether to label addiction as a 'disease'. Contrary to the prediction of neuroscientific advocates and social science critics, acceptance of a neurobiological conception of addiction did not necessarily affect beliefs about addicted persons' responsibility for their addiction. We discuss the theoretical and applied implications of these findings. Theoretically, we examine the complexity surrounding how people adopt new knowledge and its role in reshaping ethical beliefs. We also discuss the implications of these findings for the ethics of communication of neuroscientific information to reduce stigma and enhance social support for the treatment of addicted individuals