196 research outputs found

    Information-to-work conversion in single molecule experiments: from discrete to continuous feedback

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    We theoretically investigate the extractable work in single molecule unfolding-folding experiments with applied feedback. Using a simple two-state model, we obtain a description of the full work distribution, from discrete to continuous feedback. The effect of the feedback is captured by a detailed fluctuation theorem, accounting for the information aquired. We find analytical expressions for the average work extraction as well as an experimentally measurable bound thereof, which becomes tight in the continuous feedback limit. We further determine the parameters for maximal power, or rate of work extraction. While our two-state model only depends on a single, effective transition rate, we find quantitative agreement with Monte Carlo simulations of DNA hairpin unfolding-folding dynamics.Comment: 5 pages, 4 figures, 5 pages of supplementary informatio

    D7.3 Report on simulator test results and driver acceptance of PROSPECT functions

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    The process of developing new automotive systems includes various testing cycles to assure a save operation in traffic. Physical system testing on test tracks is very important for this purpose, but rather expensive and might only become possible in later stages of the development process. Using a virtual simulation environment offers a safe possibility of testing new systems in early stages of development. Aditionally, driver-in-the-loop tests at test track and in a virtual simulator make it possible to evaluate driver reaction and potential acceptance by the future users of those systems. Within PROSPECT the new functions are investigated under various aspects in several simulator studies and test track studies. This deliverable D7.3 gives detailed information of conduction and results of the each study. Three studies focus exclusively on the for Vulnerable Road Users (VRUs) specifically dangerous urban intersection scenarios. The first of those studies examines the driver behaviour in a turning situation when a byciclist might be crossing. The described phenomena are looked-but-failed-to-see and failed-to-look. The second study, which provides an initial step in this line of research, analyzed the acceptance of issued forward collision warning times. The positioning of the potential accident opponent and the subjective feeling towards the criticality of the situation by the driver were key parameters taken into account. Last, but not least the acceptance of an intersection assist autonomous emergency braking systems was tested regarding the acceptance of potential buyers. The study was run for five days in a row for each participant to be able to judge the behaviour in a comuting situation. Two studies focused on longitudinal scenarios. Both studies followed the same design, but one was conducted on a test track and the other one in a simulator. The main objective was to investigate drivers reactions to FCW warnings and Active Steering interventions in critical VRU scenarios in case of a distraction of the driver. Additionally, the test track study was used to validate the results from the simulator study. The results of those studies are the basis for a wide acceptance evaluation of the systems. No system is an asset in increasing road safety if it is not accepted by the user and therefore turned off, if it is not required the system to be default on in consumer tests. Complemented by an additional acceptance study where the participants had to give their opinion of those systems after they watched videos of dangerous situations, the acceptance was analyzed based on questionnaires developed in PROSPECT and reported in Deliverable 7.2. This wholistic approach allows an expert discussion on the potentials of the PROSPECT functions in the future

    Laboratory Analysis of Tularemia in Wild-Trapped, Commercially Traded Prairie Dogs, Texas, 2002

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    Oropharyngeal tularemia was identified as the cause of a die-off in captured wild prairie dogs at a commercial exotic animal facility in Texas. From this point source, Francisella tularensis–infected prairie dogs were traced to animals distributed to the Czech Republic and to a Texas pet shop. F. tularensis culture isolates were recovered tissue specimens from 63 prairie dogs, including one each from the secondary distribution sites. Molecular and biochemical subtyping indicated that all isolates were F. tularensis subsp. holarctica (Type B). Microagglutination assays detected antibodies against F. tularensis, with titers as great as 1:4,096 in some live animals. All seropositive animals remained culture positive, suggesting that prairie dogs may act as chronic carriers of F. tularensis. These findings demonstrate the need for additional studies of tularemia in prairie dogs, given the seriousness of the resulting disease, the fact that prairie dogs are sold commercially as pets, and the risk for pet-to-human transmission

    The tyrosine kinase inhibitor ZD6474 inhibits tumour growth in an intracerebral rat glioma model

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    Malignant glioma is characterised by extensive neovascularisation, principally influenced by vascular endothelial growth factor (VEGF). ZD6474 is a potent inhibitor of VEGF-R2 tyrosine kinase activity, but with additional inhibitory effects on other growth factors. In this study, we have investigated the effects of ZD6474 with regard to tumour growth, neovascularisation, proliferation and apoptosis in the intracerebral rat glioma model, BT4C. ZD6474 (50 and 100 mg kg−1) was given as a daily oral gavage. Animals were killed on day 19 and tumour volume was measured. Sections were stained for factor VIII, Ki-67 and for apoptosis. The ability of ZD6474 to inhibit cell growth directly was examined in vitro, using the glioma cell line BT4C and the transformed rat brain endothelial cell line RBE4. Cell growth was analysed with fluorometric microculture cytotoxicity assay to quantify the cytotoxic effects. ZD6474 significantly decreased tumour volume compared to controls. Microvascular density increased after treatment with ZD6474, and tumour cell proliferation index was reduced. There was also an increase in tumour cell apoptosis. In vitro, the growth of both cell lines was significantly reduced. The results reported justify further experimental investigations concerning the effects of ZD6474 in malignant glioma alone or in combination with other modalities

    Long-acting inhaled therapy (beta-agonists, anticholinergics and steroids) for COPD: a network meta-analysis.

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    BACKGROUND: Pharmacological therapy for chronic obstructive pulmonary disease (COPD) is aimed at relieving symptoms, improving quality of life and preventing or treating exacerbations.Treatment tends to begin with one inhaler, and additional therapies are introduced as necessary. For persistent or worsening symptoms, long-acting inhaled therapies taken once or twice daily are preferred over short-acting inhalers. Several Cochrane reviews have looked at the risks and benefits of specific long-acting inhaled therapies compared with placebo or other treatments. However for patients and clinicians, it is important to understand the merits of these treatments relative to each other, and whether a particular class of inhaled therapies is more beneficial than the others. OBJECTIVES: To assess the efficacy of treatment options for patients whose chronic obstructive pulmonary disease cannot be controlled by short-acting therapies alone. The review will not look at combination therapies usually considered later in the course of the disease.As part of this network meta-analysis, we will address the following issues.1. How does long-term efficacy compare between different pharmacological treatments for COPD?2. Are there limitations in the current evidence base that may compromise the conclusions drawn by this network meta-analysis? If so, what are the implications for future research? SEARCH METHODS: We identified randomised controlled trials (RCTs) in existing Cochrane reviews by searching the Cochrane Database of Systematic Reviews (CDSR). In addition, we ran a comprehensive citation search on the Cochrane Airways Group Register of trials (CAGR) and checked manufacturer websites and reference lists of other reviews. The most recent searches were conducted in September 2013. SELECTION CRITERIA: We included parallel-group RCTs of at least 6 months' duration recruiting people with COPD. Studies were included if they compared any of the following treatments versus any other: long-acting beta2-agonists (LABAs; formoterol, indacaterol, salmeterol); long-acting muscarinic antagonists (LAMAs; aclidinium, glycopyrronium, tiotropium); inhaled corticosteroids (ICSs; budesonide, fluticasone, mometasone); combination long-acting beta2-agonist (LABA) and inhaled corticosteroid (LABA/ICS) (formoterol/budesonide, formoterol/mometasone, salmeterol/fluticasone); and placebo. DATA COLLECTION AND ANALYSIS: We conducted a network meta-analysis using Markov chain Monte Carlo methods for two efficacy outcomes: St George's Respiratory Questionnaire (SGRQ) total score and trough forced expiratory volume in one second (FEV1). We modelled the relative effectiveness of any two treatments as a function of each treatment relative to the reference treatment (placebo). We assumed that treatment effects were similar within treatment classes (LAMA, LABA, ICS, LABA/ICS). We present estimates of class effects, variability between treatments within each class and individual treatment effects compared with every other.To justify the analyses, we assessed the trials for clinical and methodological transitivity across comparisons. We tested the robustness of our analyses by performing sensitivity analyses for lack of blinding and by considering six- and 12-month data separately. MAIN RESULTS: We identified 71 RCTs randomly assigning 73,062 people with COPD to 184 treatment arms of interest. Trials were similar with regards to methodology, inclusion and exclusion criteria and key baseline characteristics. Participants were more often male, aged in their mid sixties, with FEV1 predicted normal between 40% and 50% and with substantial smoking histories (40+ pack-years). The risk of bias was generally low, although missing information made it hard to judge risk of selection bias and selective outcome reporting. Fixed effects were used for SGRQ analyses, and random effects for Trough FEV1 analyses, based on model fit statistics and deviance information criteria (DIC). SGRQ SGRQ data were available in 42 studies (n = 54,613). At six months, 39 pairwise comparisons were made between 18 treatments in 25 studies (n = 27,024). Combination LABA/ICS was the highest ranked intervention, with a mean improvement over placebo of -3.89 units at six months (95% credible interval (CrI) -4.70 to -2.97) and -3.60 at 12 months (95% CrI -4.63 to -2.34). LAMAs and LABAs were ranked second and third at six months, with mean differences of -2.63 (95% CrI -3.53 to -1.97) and -2.29 (95% CrI -3.18 to -1.53), respectively. Inhaled corticosteroids were ranked fourth (MD -2.00, 95% CrI -3.06 to -0.87). Class differences between LABA, LAMA and ICS were less prominent at 12 months. Indacaterol and aclidinium were ranked somewhat higher than other members of their classes, and formoterol 12 mcg, budesonide 400 mcg and formoterol/mometasone combination were ranked lower within their classes. There was considerable overlap in credible intervals and rankings for both classes and individual treatments. Trough FEV1 Trough FEV1 data were available in 46 studies (n = 47,409). At six months, 41 pairwise comparisons were made between 20 treatments in 31 studies (n = 29,271). As for SGRQ, combination LABA/ICS was the highest ranked class, with a mean improvement over placebo of 133.3 mL at six months (95% CrI 100.6 to 164.0) and slightly less at 12 months (mean difference (MD) 100, 95% CrI 55.5 to 140.1). LAMAs (MD 103.5, 95% CrI 81.8 to 124.9) and LABAs (MD 99.4, 95% CrI 72.0 to 127.8) showed roughly equivalent results at six months, and ICSs were the fourth ranked class (MD 65.4, 95% CrI 33.1 to 96.9). As with SGRQ, initial differences between classes were not so prominent at 12 months. Indacaterol and salmeterol/fluticasone were ranked slightly better than others in their class, and formoterol 12, aclidinium, budesonide and formoterol/budesonide combination were ranked lower within their classes. All credible intervals for individual rankings were wide. AUTHORS' CONCLUSIONS: This network meta-analysis compares four different classes of long-acting inhalers for people with COPD who need more than short-acting bronchodilators. Quality of life and lung function were improved most on combination inhalers (LABA and ICS) and least on ICS alone at 6 and at 12 months. Overall LAMA and LABA inhalers had similar effects, particularly at 12 months. The network has demonstrated the benefit of ICS when added to LABA for these outcomes in participants who largely had an FEV1 that was less than 50% predicted, but the additional expense of combination inhalers and any potential for increased adverse events (which has been established by other reviews) require consideration. Our findings are in keeping with current National Institute for Health and Care Excellence (NICE) guidelines

    Implementation of Anaphylaxis Management Guidelines: A Register-Based Study

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    BACKGROUND: Anaphylaxis management guidelines recommend the use of intramuscular adrenaline in severe reactions, complemented by antihistamines and corticoids; secondary prevention includes allergen avoidance and provision of self-applicable first aid drugs. Gaps between recommendations and their implementation have been reported, but only in confined settings. Hence, we analysed nation-wide data on the management of anaphylaxis, evaluating the implementation of guidelines. METHODS: Within the anaphylaxis registry, allergy referral centres across Germany, Austria and Switzerland provided data on severe anaphylaxis cases. Based on patient records, details on reaction circumstances, diagnostic workup and treatment were collected via online questionnaire. Report of anaphylaxis through emergency physicians allowed for validation of registry data. RESULTS: 2114 severe anaphylaxis patients from 58 centres were included. 8% received adrenaline intravenously, 4% intramuscularly; 50% antihistamines, and 51% corticoids. Validation data indicated moderate underreporting of first aid drugs in the Registry. 20% received specific instructions at the time of the reaction; 81% were provided with prophylactic first aid drugs at any time. CONCLUSION: There is a distinct discrepancy between current anaphylaxis management guidelines and their implementation. To improve patient care, a revised approach for medical education and training on the management of severe anaphylaxis is warranted

    Compulsive Internet Use Among Adolescents: Bidirectional Parent–Child Relationships

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    Although parents experience growing concerns about their children’s excessive internet use, little is known about the role parents can play to prevent their children from developing Compulsive Internet Use (CIU). The present study addresses associations between internet-specific parenting practices and CIU among adolescents, as well as the bidirectionality of these associations. Two studies were conducted: a cross-sectional study using a representative sample of 4,483 Dutch students and a longitudinal study using a self-selected sample of 510 Dutch adolescents. Results suggest that qualitatively good communication regarding internet use is a promising tool for parents to prevent their teenage children from developing CIU. Besides, parental reactions to excessive internet use and parental rules regarding the content of internet use may help prevent CIU. Strict rules about time of internet use, however, may promote compulsive tendencies. Finally, one opposite link was found whereby CIU predicted a decrease in frequency of parental communication regarding internet use
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