Detection response tasks

Currently, many new in-vehicle information and communication systems are entering our cars. They range from media players to navigation systems to speech based systems which allow the use of the vehicles functions by speech. While these systems are intended to facilitate the driving task, some research shows they also may also have the potential to distract drivers (e.g. Santos et al., 2005). In order to evaluate to which degree such systems are suitable for the while driving, many evaluation methods have been proposed. While most of these evaluation methods allow the measurement of visual-manual distraction (e.g. eye tracking), cognitive distraction is much more complicated to measure. However, as more systems become multi-modal or purely speech-based, it is getting even more important to measure the impact of cognitive distractions. Recent studies (Merat & Jamson, 2008) explored a promising method to evaluate cognitive workload: detection response tasks (DRTs). Such detection response tasks rely on at least a dual task setting, where the impairment in a secondary task (the detection response task) is an indication of the workload imposed by the primary task. In this study three types of DRTs were evaluated: peripheral detection response task (PDRT), auditory detection response task (ADRT) and tactile detection response task (TDRT). In order to evaluate the sensitivity of each of these DRTs, cognitive tasks like the n-back task (Mehler et al., 2009) and a counting task were deployed in two levels of difficulty. Additionally, these cognitive tasks were presented in a visual, auditory, as well as pure cognitive way to clarify if any interactions between the different modalities of the DRTs and the presentation modes of the cognitive tasks exist. Results revealed significant differences between high and low levels of cognitive workload for all three types of the DRT variants evaluating the reaction time. However, a closer examination of the results showed that the PDRT is not adequately sensitive to measure increased cognitive workload on the counting task if the dependent measure is the hit rate. It is concluded that all three DRT variants are a sensitive measurement technique to assess cognitive workload. More research is needed to validate these findings on the use of real world tasks. Furthermore it has to be proven if it is possible to apply one of the DRT variants to a tertiary design (driving + test task + DRT), as this would increase the ecological validity of the method

On the use of Fractional Polynomials in Dynamic Cox Models

Despite a sophisticated research on modelling of survival data in the last years, the most popular model used in practice is still the proportional hazards regression model proposed by Cox (1972). This is mainly due to its exceptional simplicity. Nevertheless the fundamental assumption of the Cox model is the proportionality of the hazards, which particularly implies that the covariate effects are constant over time. For many applications this assumption is, however, doubtful. Other, more flexible approaches, which are able to cope with non-proportional hazards usually require non-standard estimation techniques, which are often rather complex and thus not favoured in application. Moreover, the selection of an appropriate test-statistic, to examine the improvement of the fit, is not obvious. In this paper we propose a flexible, yet simple method for modelling dynamic effects in survival data within the Cox framework. The method is based on Fractional Polynomials as introduced by Royston and Altman (1994). This allows for a transformation of the dynamic predictor which leads back to the conventional Cox model and hence fitting is straightforward using standard estimation techniques. In addition, it offers the possibility to easily verify the existence of time-variation. We describe a model selection algorithm which enables to include time-varying effects only when evidence is given in the data, in order to construct a model, which is just as complex as needed. We illustrate the properties of the approach in a simulation study and an application to gastric carcinoma data and compare it with other methods (e.g. the residual score test and smoothed Schoenfeld residuals of Grambsch and Therneau, 1994; natural smoothing splines of Hastie and Tibshirani, 1993)

Der Cross-Shaper: ein neues Sportgerät zum gesunden und effektiven Ganzkörpertraining – Ergebnisse einer biomechanischen Feldstudie

ZusammenfassungDer Cross-Shaper wurde entwickelt, um in den Bewegungsablauf des Walkens den Oberkörper effektiver einbeziehen zu können. Diese Feldstudie konnte deutlich positive gesundheitliche Effekte des Cross-Shapers zeigen, die umfassender ausgeprägt sind als beim Walking und Nordic Walking. Der Bewegungsverlauf ist harmonisch. Der stoßreduzierte Abdruck ist effektiver als beim Nordic Walking. Der Oberkörper wird vermehrt aufgerichtet und die Wirbelsäule effektiv entlastet und mobilisiert. Weite Teile der Muskulatur werden physiologisch gleichermaßen trainiert. Positive Effekte auf das Herz-Kreislauf-System sind gegenüber Walking und Nordic Walking deutlich erhöht.SummaryThe Cross-Shaper was developed to include the upper body more effectively in the motion sequence of walking. Results of this field study clearly show positive health effects from cross-shaper, which are pronounced more extensive than in walking and nordic walking. The path of movement is harmonious. The shock reduced push off is considerably more effective than in nordic walking. The upper body is increasingly erected and the spine is relieved and mobilized effectively. Large parts of muscles were physiologically trained equally effective. Positive effects on the cardiovascular system are increased considerably compared to walking and nordic walking

CROSS-SHAPING – THE MORE EFFECTIVE NORDIC WALKING? RESULTS OF A BIOMECHANICAL FIELD STUDY

Cross-shaping is a new developed kind of nordic walking. The main difference between nordic walking and cross-shaping is the use of special sticks with forearm shells and wheels. The purpose of this study was to analyze the health effects of cross-shaping and to compare the results with own previous studies of nordic walking. Results clearly show positive health effects from cross-shaping, which are more extensive than in walking and nordic walking. Cross-shaping is harmonious similar to cross-country skiing in classic style. Push off is more effective than in nordic walking. Upper body is more erected and spine is relieved and mobilized effectively. Large parts of muscles of the upper and lower extremities were physiologically trained effective. Positive effects on the cardiovascular system are increased considerably compared to walking and nordic walking

Identifying Factors Associated with Consumers’ Adoption of e-Mobility—A Systematic Literature Review

Electrification of road transport—replacing internal combustion engine vehicles with new energy vehicles such as electric vehicles (EVs)—seems to be a promising step towards achieving sustainable urban development, yet the diffusion of EVs is proceeding slowly. Investigating this phenomenon, researchers have provided numerous findings. However, these findings also created a fragmented and heterogeneous body of literature. This article applies a systematic literature review to establish a status quo of factors associated with the adoption of EVs. A total of 49 articles were identified and analyzed in detail for their contribution to EV adoption. The results from the systematic literature review were synthesized. The article ends with implications for policymakers and suggests fruitful research avenues for future investigations

Personality traits and virtual reality performance

Background: Surgeons' personalities have been described as different from those of the general population, but this was based on small descriptive studies limited by the choice of evaluation instrument. Furthermore, although the importance of the human factor in team performance has been recognized, the effect of personality traits on technical performance is unknown. This study aimed to compare surgical residents' personality traits with those of the general population and to evaluate whether an association exists between their personality traits and technical performance using a virtual reality (VR) laparoscopy simulator. Methods: In this study, 95 participants (54 residents with basic, 29 with intermediate laparoscopic experience, and 12 students) underwent personality assessment using the NEO-Five Factor Inventory and performed five VR tasks of the Lap Mentor™ basic tasks module. The residents' personality traits were compared with those of the general population, and the association between VR performance and personality traits was investigated. Results: Surgical residents showed personality traits different from those of the general population, demonstrating lower neuroticism, higher extraversion and conscientiousness, and male residents showed greater openness. In the multivariable analysis, adjusted for gender and surgical experience, none of the personality traits was found to be an independent predictor of technical performance. Conclusions: Surgical residents present distinct personality traits that differ from those of the general population. These traits were not found to be associated with technical performance in a virtual environment. The traits may, however, play an important role in team performance, which in turn is highly relevant for optimal surgical performanc

Wind Power Persistence Characterized by Superstatistics

Mitigating climate change demands a transition towards renewable electricity generation, with wind power being a particularly promising technology. Long periods either of high or of low wind therefore essentially define the necessary amount of storage to balance the power system. While the general statistics of wind velocities have been studied extensively, persistence (waiting) time statistics of wind is far from well understood. Here, we investigate the statistics of both high- and low-wind persistence. We find heavy tails and explain them as a superposition of different wind conditions, requiring q-exponential distributions instead of exponential distributions. Persistent wind conditions are not necessarily caused by stationary atmospheric circulation patterns nor by recurring individual weather types but may emerge as a combination of multiple weather types and circulation patterns. This also leads to Fréchet instead of Gumbel extreme value statistics. Understanding wind persistence statistically and synoptically may help to ensure a reliable and economically feasible future energy system, which uses a high share of wind generation

Surgery for ischemic colitis: outcome and risk factors for in-hospital mortality

Purpose: Surgery for ischemic colitis is associated with high perioperative morbidity and mortality, but the risk factors for mortality and major surgical complications are unclear. Methods: In this retrospective single institution cohort study of all patients undergoing colorectal surgery for histologically proven ischemic colitis between 2004 and 2010, we evaluated surgical outcomes and risk factors for in-hospital mortality and major surgical complications. Results: For the 100 patients included in the study, in-hospital mortality was 54%; major surgical complications, defined as anastomotic leakage or rectal stump and stoma complications, occurred in 16%. In the multivariable analysis, hospital death was more likely in patients with right-sided (odds ratio [OR] 3.8; 95% confidence interval [CI] 1.2, 12; P = 0.022) or pan-colonic ischemia (OR 11; 95% CI 2.8, 39; P < 0.001), both relative to left-sided ischemia. Decreased preoperative pH level (OR 2.5 per 0.1 decrease; 95% CI 1.5, 4.1; P < 0.001) and prior cardiac or aortic surgery (OR 2.4; 95% CI 0.82, 6.8; P = 0.109) were further important risk factors for in-hospital mortality. Major postoperative surgical complications were more likely in patients with ischemic alterations at the resection margin of the histological specimen (OR 3.7; 95% CI 1.2, 11; P = 0.022). Conclusions: Colonic resection for ischemic colitis is associated with high in-hospital mortality, especially in patients with right-sided or pan-colonic ischemia. In patients developing acidosis, early laparotomy is essential. Since resection margins' affection seems to be underestimated upon surgery, resections should be performed wide enough within healthy tissue

Improved detection of microbial ureteral stent colonisation by sonication

Purpose: The diagnosis of microbial ureteral stent colonisation (MUSC) is difficult, since routine diagnostic techniques do not accurately detect microorganisms embedded in biofilms. New methods may improve diagnostic yield and understanding the pathophysiology of MUSC. The aim of the present study was to evaluate the potential of sonication in the detection of MUSC and to identify risk factors for device colonisation. Methods: Four hundred and eight polyurethane ureteral stents of 300 consecutive patients were prospectively evaluated. Conventional urine culture (CUC) was obtained prior to stent placement and device removal. Sonication was performed to dislodge adherent microorganisms. Data of patient sex and age, indwelling time and indication for stent placement were recorded. Results: Sonicate-fluid culture detected MUSC in 36%. Ureteral stents inserted during urinary tract infection (UTI) were more frequently colonised (59%) compared to those placed in sterile urine (26%; P<0.001). Female sex (P<0.001) and continuous stenting (P<0.005) were significant risk factors for MUSC; a similar trend was observed in patients older than 50years (P=0.16). MUSC and indwelling time were positively correlated (P<0.005). MUSC was accompanied by positive CUC in 36%. Most commonly isolated microorganisms were Coagulase-negative staphylococci (18.3%), Enterococci (17.9%) and Enterobacteriaceae (16.9%). Conclusions: Sonication is a promising approach in the diagnosis of MUSC. Significant risk factors for MUSC are UTI at the time of stent insertion, female sex, continuous stenting and indwelling time. CUC is a poor predictor of MUSC. The clinical relevance of MUSC needs further evaluation to classify isolated microorganism properly as contaminants or pathogen

Improved detection of microbial ureteral stent colonisation by sonication

Purpose: The diagnosis of microbial ureteral stent colonisation (MUSC) is difficult, since routine diagnostic techniques do not accurately detect microorganisms embedded in biofilms. New methods may improve diagnostic yield and understanding the pathophysiology of MUSC. The aim of the present study was to evaluate the potential of sonication in the detection of MUSC and to identify risk factors for device colonisation. Methods: Four hundred and eight polyurethane ureteral stents of 300 consecutive patients were prospectively evaluated. Conventional urine culture (CUC) was obtained prior to stent placement and device removal. Sonication was performed to dislodge adherent microorganisms. Data of patient sex and age, indwelling time and indication for stent placement were recorded. Results: Sonicate-fluid culture detected MUSC in 36%. Ureteral stents inserted during urinary tract infection (UTI) were more frequently colonised (59%) compared to those placed in sterile urine (26%; P<0.001). Female sex (P<0.001) and continuous stenting (P<0.005) were significant risk factors for MUSC; a similar trend was observed in patients older than 50years (P=0.16). MUSC and indwelling time were positively correlated (P<0.005). MUSC was accompanied by positive CUC in 36%. Most commonly isolated microorganisms were Coagulase-negative staphylococci (18.3%), Enterococci (17.9%) and Enterobacteriaceae (16.9%). Conclusions: Sonication is a promising approach in the diagnosis of MUSC. Significant risk factors for MUSC are UTI at the time of stent insertion, female sex, continuous stenting and indwelling time. CUC is a poor predictor of MUSC. The clinical relevance of MUSC needs further evaluation to classify isolated microorganism properly as contaminants or pathogen