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We analyze the relationship between entrepreneurship and decision-making under risk and uncertainty using the Columbia Card Task: an experimental task eliciting affective decision-making under conditions of risk and uncertainty. In a sample of 127 university students, we find robust evidence that individual entrepreneurial orientation (IEO) is negatively related to decision-making under risk and uncertainty. In addition, we show that distinguishing the subscales of IEO is key to understanding this relationship, since while the relationship is negative for the Proactiveness and Innovativeness subscales, it is positive for the Risk taking subscale. Moderation analyses show that heterogeneous sensitivity towards possible gains and losses explains the main relationship.

Risk behavior can have substantial consequences for health, well-being, and functioning. Previous studies have shown an association between real-world risk behavior and risk behavior on experimental tasks, such as the Columbia Card Task, but their modeling is challenging for several reasons. First, many of the experimental risk tasks may end prematurely leading to censored observations. Second, certain outcome values can be more attractive than others. Third, a priori unknown groups of participants can react differently to certain risk-levels. Here, we propose the Censored Mixture Model (CMM), which models risk taking while handling censoring, experimental conditions, and attractiveness to certain outcomes., Comment: 29 pages, 9 figures

This clinical case presentation describes the disease trajectory in two patients who presented with psychiatric symptoms as a result of abnormal serum glucocorticoid levels. One case involves a 58-year-old man with hypercortisolism, the other case concerns a 55-year-old woman with hypocortisolism. In both cases there was a considerable diagnostic delay in recognizing the underlying adrenal gland pathology. Abnormal glucocorticoid levels, caused by endocrine disorders, often results in psychiatric symptoms. Delay in diagnosis may have adverse consequences. Hyper- or hypocortisolism should be considered in patients who present with an atypical presentation of psychiatric symptoms. Moreover, the absence of specific physical signs or symptoms at first presentation in such patients does not exclude an underlying endocrinological cause. Therefore, physical and psychiatric reassessment of such patients should be considered at regular intervals.

The aim of this review paper is to give an overview of the research activities of GKSS in the field of polymer based membranes. After summarizing the historic development of membrane science at GKSS, it describes different classes of polymeric materials for membranes, and the characterization of membranes. The design of membrane-based separation processes followed by examples of applications will also be presented. In the last chapter we will try to give an outlook for the future activities in membrane research.

An increasing number of hybrid processes consisting of conventional unit operations and vapour permeation modules have been suggested in recent years. To facilitate accurate process design, rigorous models of this novel membrane process are essential. By comparing experimental results obtained from a pilot plant, it was shown that simply solving the material balances and assuming constant permeances is not sufficient to predict the operating behaviour of a vapour permeation module. In order to reflect the experimental results it was necessary to consider the concentration, temperature and pressure dependency of the permeation process through the membrane as well as the mass transfer restriction in the boundary layer on the feed side. The introduced model is capable of taking account of these effects and predicts the experimental results satisfactorily. The model was written using the commercial, equation-oriented process simulator Aspen Custom Modeler and hence can easily be integrated with commercial process simulation packages.

A mass-tagged N-mesityl imidazolinium salt with four additional -CH(2)NCy(2) substituents was synthesized, leading to a molecular mass of nearly 1100 g mol(-1) in the corresponding carbene ligand. This mass-tagged ligand was used to generate the respective Grubbs II and Grubbs-Hoveyda type complexes. The catalytic activity of the latter complex was tested in several olefin metathesis reactions and found to be slightly superior to that of the related N-mesityl based complex. In batchwise solvent resistant nanofiltration experiments the ruthenium complex dissolved in toluene and following a metathesis reactions was efficiently retained (>99.8 %) by a single nanofiltration; the permeate contained less than 4 ppm of Ru. Equally efficient catalyst retention was observed in a membrane reactor utilized for the continuous synthesis of a RCM product.

Dose limiting systemic toxicity prevents sufficient exploitation of the steep dose response relationship of most anticancer agents. In our rat liver tumour model (the CC531 colorectal carcinoma), isolated liver perfusion allows administration of higher doses of mitomycin C than hepatic artery infusion, while systemic toxicity remains minimal. To determine the temporal pattern of mitomycin C induced cytokinetic changes, we analysed flow cytometric DNA histograms of CC531 liver tumours from rats treated with high dose mitomycin C (3.2 mg kg-1) via hepatic artery infusion and sacrificed at different time intervals after treatment. Between 12 and 36 h after treatment, the fraction of cells in late S and G2/M phase had markedly increased. The effects of administration of the respective maximally tolerated doses of mitomycin C in isolated liver perfusion and via hepatic artery infusion on progression of tumour cells through the cell cycle and on gross tumour growth were compared. Isolated liver perfusion with mitomycin C resulted in a significant increase in the proportion of cells in mid and late S, and in some accumulation of cells in early S and G2/M phase at 24 and 48 h after treatment. In contrast, after hepatic artery infusion a significant increase of the fraction of cells in G2/M phase was observed at 24 h after treatment. Monitoring tumour growth after isolated liver perfusion five out of seven rats showed a complete tumour remission, while after hepatic artery infusion only a minimal growth delay was detected. This study demonstrates that isolated liver perfusion in the rat CC531 liver tumour model allows the administration of a well-tolerated dose of mitomycin C being high enough to induce a marked DNA synthesis inhibition and even complete tumour remission.

Background Low transsphincteric fistulas less than 1/3 of the sphincter complex are easy to treat by fistulotomy with a high success rate. High transsphincteric fistulas remain a surgical challenge. Various surgical procedures are available, but recurrence rates of these techniques are disappointingly high. The mucosal flap advancement is considered the gold standard for the treatment of high perianal fistula of cryptoglandular origin by most colorectal surgeons. In the literature a recurrence rate between 0 and 63% is reported for the mucosal flap advancement. Recently Armstrong and colleagues reported on a new biologic anal fistula plug, a bioabsorbable xenograft made of lyophilized porcine intestinal submucosa. Their prospective series of 15 patients with high perianal fistula treated with the anal fistula plug showed promising results. The anal fistula plug trial is designed to compare the anal fistula plug with the mucosal flap advancement in the treatment of high perianal fistula in terms of success rate, continence, postoperative pain, and quality of life. Methods/design The PLUG trial is a randomized controlled multicenter trial. Sixty patients with high perianal fistulas of cryptoglandular origin will be randomized to either the fistula plug or the mucosal advancement flap. Study parameters will be anorectal fistula closure-rate, continence, post-operative pain, and quality of life. Patients will be followed-up at two weeks, four weeks, and 16 weeks. At the final follow-up closure rate is determined by clinical examination by a surgeon blinded for the intervention. Discussion Before broadly implementing the anal fistula plug results of randomized trials using the plug should be awaited. This randomized controlled trial comparing the anal fistula plug and the mucosal advancement flap should provide evidence regarding the effectiveness of the anal fistula plug in the treatment of high perianal fistulas. Trial registration ISRCTN: 97376902

Traditionally, ultrasonic inspection methods are developed using extensive lab measurements. This approach provides limited insight in the interaction of waves with artificial and realistic defects. However, for a thorough insight in the factors that determine the reliability it is necessary to understand the wave field inside the object of inspection. Therefore, we propose the usage of advanced numerical simulation tools which visualize the full-elastic wave field. This way a connection can be made between the recorded signal and the wave field inside the test object. These insights improve the performance of an inspection method and reduce time spent on experimental validation. © 2008 American Institute of Physics.

Postsurgical intra-abdominal adhesions pose a significant medical problem in the Western world, and in the past decade progress has been made in understanding their pathophysiology. The early balance between fibrin formation and degradation in the peritoneal cavity during and after surgery seems to be a major determinant of adhesion formation. Postsurgical inhibition of fibrinolytic activity severely impairs fibrin breakdown. Adhesive small-bowel obstruction, inadvertent enterotomy at reoperation, prolonged operative time dividing adhesions, increased clinical workload and high financial costs are important adhesion-related problems discussed in this review. The cumulative risk of adhesive small-bowel obstruction after (sub)total colectomy is 11% within 1 year, increasing to 30% at 10 years. One of five patients undergoing reoperation suffers from inadvertent enterotomy, resulting in significant postoperative morbidity and mortality. Roughly 3% of all surgical admissions are associated with intra-abdominal adhesions. Clinical prospective trials have recently been designed to investigate the efficacy of barrier membranes and gels in the reduction of abdominal and pelvic adhesions and prevention of long-term morbidity, e.g., adhesive bowel obstruction and infertility in women. Early results are promising and contribute to the increased interest among clinicians in postsurgical adhesion formation and its consequences.

BackgroundInadvertent enterotomy is a feared complication of adhesiotomy during abdominal reoperation. The nature and extent of this adhesion-associated problem are unknown.MethodsThe records of all patients who underwent reoperation between July 1995 and September 1997 were reviewed retrospectively for inadvertent enterotomy, risk factors were analysed using univariate and multivariate parameters, and postoperative morbidity and mortality rates were assessed.ResultsInadvertent enterotomy occurred in 52 (19 per cent) of 270 reoperations. Dividing adhesions in the lower abdomen and pelvis, in particular, caused bowel injury. In univariate analysis body mass index was significantly higher in patients with inadvertent enterotomy (mean(s.d.) 25·5(4·6) kg/m2) than in those without enterotomy (21·9(4·3) kg/m2) (P < 0·03). Patient age and three or more previous laparotomies appeared to be independent parameters predicting inadvertent enterotomy (odds ratio (95 per cent confidence interval) 1·9 (1·3–2·7) and 10·4 (5·0–21·6) respectively; P < 0·001). Patients with inadvertent enterotomy had significantly more postoperative complications (P < 0·01) and urgent relaparotomies (P < 0·001), a higher rate of admission to the intensive care unit (P < 0·001) and parenteral nutrition usage (P < 0·001), and a longer postoperative hospital stay (P < 0·001).ConclusionThe incidence of inadvertent enterotomy during reoperation is high. This adhesion-related complication has an impact on postoperative morbidity.

Agaricus bisporus grew well in submerged culture in a medium containing malt extract, phosphate, and casein. Moderate growth occurred in defined media containing glucose, asparagine, phenylalanine, vitamins and minerals. Other amino acids did not stimulate growth.