757 research outputs found

    Decision Making in Virtual Worlds: An Experimental Test of Altruism, Fairness and Presence

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    Virtual worlds are gaining in popularity and are proposed as a test laboratory for the real world. Inthese virtual worlds users act via their avatars and make decisions for them. In this paper, we analyzethe decision making in virtual worlds in an experiment conducted in a virtual world, as well as in thereal world over the internet, for the same set of subjects. For this purpose, we develop hypotheses fordecision making in the context of a classic economic experiment (the Dictator Game). We find similardecisions in the virtual and the real world with respect to sharing. Altruism has a significant influencein the real world setting but not in the virtual world; fairness is insignificant in both settings. Weidentify the feeling of presence in one’s avatar and potential satiation effects as factors that influencedecisions regarding the allocation of resources in the virtual world

    Persistent risk for new, subsequent new and recurrent hepatocellular carcinoma despite successful anti-hepatitis B virus therapy and tumor ablation: The need for hepatitis B virus cure.

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    Hepatitis B virus (HBV) is one of the most significant hepatocarcinogens. The ultimate goal of anti-HBV treatment is to prevent the development of hepatocellular carcinoma (HCC). During the last two decades, with the use of currently available anti-HBV therapies (lamivudine, entecavir and tenofovir disoproxil fumatate), there has been a decrease in the incidence of HBV-associated HCC (HBV-HCC). Furthermore, several studies have demonstrated a reduction in recurrent or new HCC development after initial HCC tumor ablation. However, during an observation period spanning 10 to 20 years, several case reports have demonstrated the development of new, subsequent new and recurrent HCC even in patients with undetectable serum HBV DNA. The persistent risk for HCC is attributed to the presence of covalently closed circular DNA (cccDNA) in the hepatocyte nucleus which continues to work as a template for HBV replication. While a functional cure (loss of hepatitis B surface antigen and undetectable viral DNA) can be attained with nucleos(t)ide analogues, these therapies do not eliminate cccDNA. Of utmost importance is successful eradication of the transcriptionally active HBV cccDNA from hepatocyte nuclei which would be considered a complete cure. The unpredictable nature of HCC development in patients with chronic HBV infection shows the need for a complete cure. Continued support and encouragement for research efforts aimed at developing curative therapies is imperative. The aims of this minireview are to highlight these observations and emphasize the need for a cure for HBV

    Modeling and measuring intracellular fluxes of secreted recombinant protein in Pichia pastoris with a novel 34S labeling procedure

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    <p>Abstract</p> <p>Background</p> <p>The budding yeast <it>Pichia pastoris </it>is widely used for protein production. To determine the best suitable strategy for strain improvement, especially for high secretion, quantitative data of intracellular fluxes of recombinant protein are very important. Especially the balance between intracellular protein formation, degradation and secretion defines the major bottleneck of the production system. Because these parameters are different for unlimited growth (shake flask) and carbon-limited growth (bioreactor) conditions, they should be determined under "production like" conditions. Thus labeling procedures must be compatible with minimal production media and the usage of bioreactors. The inorganic and non-radioactive <sup>34</sup>S labeled sodium sulfate meets both demands.</p> <p>Results</p> <p>We used a novel labeling method with the stable sulfur isotope <sup>34</sup>S, administered as sodium sulfate, which is performed during chemostat culivations. The intra- and extracellular sulfur 32 to 34 ratios of purified recombinant protein, the antibody fragment Fab3H6, are measured by HPLC-ICP-MS. The kinetic model described here is necessary to calculate the kinetic parameters from sulfur ratios of consecutive samples as well as for sensitivity analysis. From the total amount of protein produced intracellularly (143.1 μg g<sup>-1 </sup>h<sup>-1 </sup>protein per yeast dry mass and time) about 58% are degraded within the cell, 35% are secreted to the exterior and 7% are inherited to the daughter cells.</p> <p>Conclusions</p> <p>A novel <sup>34</sup>S labeling procedure that enables <it>in vivo </it>quantification of intracellular fluxes of recombinant protein under "production like" conditions is described. Subsequent sensitivity analysis of the fluxes by using MATLAB, indicate the most promising approaches for strain improvement towards increased secretion.</p

    Psychometric properties of the Patient Assessment Of Chronic Illness Care measure: acceptability, reliability and validity in United Kingdom patients with long-term conditions.

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    BACKGROUND: The Patient Assessment of Chronic Illness Care (PACIC) is a US measure of chronic illness quality of care, based on the influential Chronic Care Model (CCM). It measures a number of aspects of care, including patient activation; delivery system design and decision support; goal setting and tailoring; problem-solving and contextual counselling; follow-up and coordination. Although there is developing evidence of the utility of the scale, there is little evidence about its performance in the United Kingdom (UK). We present preliminary data on the psychometric performance of the PACIC in a large sample of UK patients with long-term conditions. METHOD: We collected PACIC, demographic, clinical and quality of care data from patients with long-term conditions across 38 general practices, as part of a wider longitudinal study. We assess rates of missing data, present descriptive and distributional data, assess internal consistency, and test validity through confirmatory factor analysis, and through associations between PACIC scores, patient characteristics and related measures. RESULTS: There was evidence that rates of missing data were high on PACIC (9.6% - 15.9%), and higher than on other scales used in the same survey. Most PACIC sub-scales showed reasonable levels of internal consistency (alpha = 0.68 - 0.94), responses did not demonstrate high skewness levels, and floor effects were more frequent (up to 30.4% on the follow up and co-ordination subscale) than ceiling effects (generally <5%). PACIC demonstrated preliminary evidence of validity in terms of measures of long-term condition care. Confirmatory factor analysis suggested that the five factor PACIC structure proposed by the scale developers did not fit the data: reporting separate factor scores may not always be appropriate. CONCLUSION: The importance of improving care for long-term conditions means that the development and validation of measures is a priority. The PACIC scale has demonstrated potential utility in this regard, but further assessment is required to assess low levels of completion of the scale, and to explore the performance of the scale in predicting outcomes and assessing the effects of interventions.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

    Quitting patient care and career break intentions among general practitioners in South West England: findings of a census survey of general practitioners

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    Objective: Given recent concerns regarding general practitioner (GP) workforce capacity, we aimed to describe GPs’ career intentions, especially those which might impact on GP workforce availability over the next 5 years. Design: Census survey, conducted between April and June 2016 using postal and online responses , of all GPs on the National Health Service performers list and eligible to practise in primary care. Two reminders were used as necessary. Setting: South West England (population 3.5  million), a region with low overall socioeconomic deprivation. Participants: Eligible GPs were 2248 out of 3370 (67 % response rate). Main outcome measures: Reported likelihood of permanently leaving or reducing hours spent in direct patient care or of taking a career break within the next 5 years and present morale weighted for non-response. Results: Responders included 217 7 GPs engaged in patient care. Of these, 863 (37% weighted, 95%  CI 35 % to 39 %) reported a high likelihood of quitting direct patient care within the next 5 years. Overall, 1535 (70% weighted, 95%  CI 68 % to 72 %) respondents reported a career intention that would negatively impact GP workforce capacity over the next 5 years, through permanently leaving or reducing hours spent in direct patient care, or through taking a career break. GP age was an important predictor of career intentions; sharp increases in the proportion of GPs intending to quit patient care were evident from 52 years. Only 305 (14% weighted, 95%  CI 13 % to 16 %) reported high morale, while 1195 ( 54 % weighted, 95%  CI 52 % to 56 %) reported low morale. Low morale was particularly common among GP partners. Current morale strongly predicted GPs’ career intentions; those with very low morale were particularly likely to report intentions to quit patient care or to take a career break. Conclusions: A substantial majority of GPs in South West England report low morale. Many are considering career intentions which, if implemented, would adversely impact GP workforce capacity within a short time period. Study registration: NIHR HS&DR - 14/196/02, UKCRN ID 20700

    Computational modelling and experimental tank testing of the multi float WaveSub under regular wave forcing

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    A submerged wave device generates energy from the relative motion of floating bodies. In WaveSub, three floats are joined to a reactor; each connected to a spring and generator. Electricity generated damps the orbital movements of the floats. The forces are non-linear and each float interacts with the others. Tuning to the wave climate is achieved by changing the line lengths, so there is a need to understand the performance trade-offs for a large number of configurations. This requires an efficient, large displacement, multidirectional, multi-body numerical scheme. Results from a 1/25 scale wave basin experiment are described. Here, we show that a time domain linear potential flow formulation (Nemoh, WEC-Sim) can match the tank testing provided that suitably tuned drag coefficients are employed. Inviscid linear potential models can match some wave device experiments; however, additional viscous terms generally provide better accuracy. Scale experiments are also prone to mechanical friction, and we estimate friction terms to improve the correlation further. The resulting error in mean power between numerical and physical models is approximately 10%. Predicted device movement shows a good match. Overall, drag terms in time domain wave energy modelling will improve simulation accuracy in wave renewable energy device design

    Psychosocial effects of an Ebola outbreak at individual, community and international levels.

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    The 2013-2016 Ebola outbreak in Guinea, Liberia and Sierra Leone was the worst in history with over 28,000 cases and 11,000 deaths. Here we examine the psychosocial consequences of the epidemic. Ebola is a traumatic illness both in terms of symptom severity and mortality rates. Those affected are likely to experience psychological effects due to the traumatic course of the infection, fear of death and experience of witnessing others dying. Survivors can also experience psychosocial consequences due to feelings of shame or guilt (e.g. from transmitting infection to others) and stigmatization or blame from their communities. At the community level, a cyclical pattern of fear occurs, with a loss of trust in health services and stigma, resulting in disruptions of community interactions and community break down. Health systems in affected countries were severely disrupted and overstretched by the outbreak and their capacities were significantly reduced as almost 900 health-care workers were infected with Ebola and more than 500 died. The outbreak resulted in an increased need for health services, reduced quality of life and economic productivity and social system break down. It is essential that the global response to the outbreak considers both acute and long-term psychosocial needs of individuals and communities. Response efforts should involve communities to address psychosocial need, to rebuild health systems and trust and to limit stigma. The severity of this epidemic and its long-lasting repercussions should spur investment in and development of health systems

    Detection of missense mutations by single-strand conformational polymorphism (SSCP) analysis in five dysfunctional variants of coagulation factor VII

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    Five unrelated subjects with dysfunctional coagulation factor VII (FVII) were studied In order to Identify missense mutations affecting function. Exons 2 to 8 and the Intron-exon Junctions of their FVIl genes were amplified from peripheral white blood cell DNA by PCR and screened by SSCP analysis. DNA fragments showing aberrant mobility were sequenced. The following mutations were Identified: In case 1 (FVII: C <1%, FVIl:Ag 18%) a heterozygous A to G transltion at nucleotlde 8915 In exon 6 results In the amlno acid substitution Lys-137 to Glu near the C-termlnus of the FVlla llght chaln; In case 2 (FVII: C 7%, FVll:Ag 47%) a heterozygous A to G transltion at nucleotide 7834 In exon 5 results in the substitution of Gin-100 by Arg in the second EGF-like domain; In case 3 (FVll:C 20%, FVIl:Ag 76%) a homozygous G to A transition at nucleotide position 6055 in exon 4 was detected resulting in substitution of Arg-79 by Gin in the first EGF-like domain; in case 5 (FVIl:C 10%, FVIl:Ag 52%) a heterozygous C to T transition at nucleotide position 6054 in exon 4 also results in the substitution of Arg79, but in this case it is replaced by Trp; case 4 (FVll:C <1%, FVIl:Ag 100%) was homozygous for a previously reported mutation (G to A) at nucleotide position 10715 in exon 8, substituting Gin for Arg at position 304 in the protease domain. Cases 1,2 and 5 evidently have additional undetected mutation
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