980 research outputs found
Welfare Stigma in the Lab: Evidence of Social Signaling
Using a laboratory experiment, we present first evidence that stigmatization through public exposure causally reduces the take-up of an individually beneficial transfer. Our design exogenously varies the informativeness of the take-up decision by varying whether transfer eligibility is based on ability or luck, and how the transfer is financed. We find that subjects avoid the inference both of being low-skilled and of being willing to live off others. Using a placebo treatment we can exclude other explanations for the observed stigma effect. In the experiment, social stigmatization implies a reduction in the take-up rate of 30 percentage points
On the exposure of insurance companies to sovereign risk − portfolio investments and market forces 1
A sovereign debt crisis can have significant knock-on effects in the financial markets and put financial stability at risk. This paper focuses on the transmission of sovereign risk to insurance companies as some of the largest institutional investors in the sovereign bond market. We use a firm level panel dataset that covers large insurance companies, banks and non-financial firms from nine countries over the time period from 1 January 2008 to 1 May 2013. We find significant and robust transmission effects from sovereign risk to domestic insurers. The impact on insurers is not significantly different from that on banks but larger than for non-financial firms. We find that systemically important insurers are more closely linked to the domestic sovereign. Based on European data, we show that risks in sovereign bond portfolios are an important driver of insurer risk, which is not reflected in current insurance regulation (incl. Solvency II in Europe)
Reaction time in a visual 4-choice reaction time task: ERP effects of motor preparation and hemispheric involvement
Reaction time (RT), the most common measure of CNS efficiency, shows intra- and inter-individual variability. This may be accounted for by hemispheric specialization, individual neuroanatomy, and transient functional fluctuations between trials. To explore RT on these three levels, ERPs were measured in a visual 4-choice RT task with lateralized stimuli (left lateral, left middle, right middle, and right lateral) in 28 healthy right-handed subjects. We analyzed behavioral data, ERP microstates (MS), N1 and P3 components, and trial-by-trial variance. Across subjects, the N1 component was contralateral to the stimulation side. N1-MSs were stronger over the left hemisphere, and middle stimulation evoked stronger activation than lateral stimulation in both hemispheres. The P3 was larger for the right visual field stimulation. RTs were shorter for the right visual hemifield stimulation/right hand responses. Within subjects, covariance analysis of single trial ERPs with RTs showed consistent lateralized predictors of RT over the motor cortex (MC) in the 112-248Â ms interval. Decreased RTs were related to negativity over the MC contralateral to the stimulation side, an effect that could be interpreted as the lateralized readiness potential (LRP), and which was strongest for right side stimulation. The covariance analysis linking individual mean RTs and individual mean ERPs showed a frontal negativity and an occipital positivity correlating with decreased RTs in the 212-232Â ms interval. We concluded that a particular RT is a composite measure that depends on the appropriateness of the motor preparation to a particular response and on stimulus lateralization that selectively involves a particular hemisphere
Computational Modeling in Liver Surgery
The need for extended liver resection is increasing due to the growing incidence of liver tumors in aging societies. Individualized surgical planning is the key for identifying the optimal resection strategy and to minimize the risk of postoperative liver failure and tumor recurrence. Current computational tools provide virtual planning of liver resection by taking into account the spatial relationship between the tumor and the hepatic vascular trees, as well as the size of the future liver remnant. However, size and function of the liver are not necessarily equivalent. Hence, determining the future liver volume might misestimate the future liver function, especially in cases of hepatic comorbidities such as hepatic steatosis. A systems medicine approach could be applied, including biological, medical, and surgical aspects, by integrating all available anatomical and functional information of the individual patient. Such an approach holds promise for better prediction of postoperative liver function and hence improved risk assessment. This review provides an overview of mathematical models related to the liver and its function and explores their potential relevance for computational liver surgery. We first summarize key facts of hepatic anatomy, physiology, and pathology relevant for hepatic surgery, followed by a description of the computational tools currently used in liver surgical planning. Then we present selected state-of-the-art computational liver models potentially useful to support liver surgery. Finally, we discuss the main challenges that will need to be addressed when developing advanced computational planning tools in the context of liver surgery.Peer Reviewe
Social anxiety in adolescents and young adults from the general population: an epidemiological characterization of fear and avoidance in different social situations
Social Anxiety Disorder (SAD) and, more generally, social fears are common in young people. Although avoidance behaviors are known to be an important maintaining factor of social anxiety, little is known about the severity and occurrence of avoidance behaviors in young people from the general population, hampering approaches for early identification and intervention. Symptoms, syndromes, and diagnoses of DSM-5 mental disorders including SAD were assessed in a random population-based sample of 14-21-year-olds (n = 1,180) from Dresden, Germany, in 2015/2016 using a standardized diagnostic interview (DIA-X-5/D-CIDI). An adapted version of the Liebowitz Social Anxiety Scale was used to ascertain the extent of social fears and avoidance. Diagnostic criteria for lifetime SAD were met by n = 82 participants, resulting in a weighted lifetime prevalence of 6.6%. Social anxiety was predominantly reported for test situations and when speaking or performing in front of others. Avoidance was most prevalent in the latter situations. On average, anxiety and avoidance first occurred at ages 11 and 12, respectively, with avoidance occurring in most cases either at about the same age as anxiety or slightly later. In the total sample, lifetime prevalence for most DSM-5 disorders increased with the severity of social anxiety and avoidance. Results underline the need for preventive or early intervention efforts especially regarding test anxiety and fear and avoidance of speaking in front of others. These situations are particularly relevant in youth. Avoidance behaviors may also be discussed as diagnostic marker for early case identification
Nanoscale Imaging Reveals a Tetraspanin-CD9 Coordinated Elevation of Endothelial ICAM-1 Clusters
Endothelial barriers have a central role in inflammation as they allow or deny the passage of leukocytes from the vasculature into the tissue. To bind leukocytes, endothelial cells form adhesive clusters containing tetraspanins and ICAM-1, so-called endothelial adhesive platforms (EAPs). Upon leukocyte binding, EAPs evolve into docking structures that emanate from the endothelial surface while engulfing the leukocyte. Here, we show that TNF-α is sufficient to induce apical protrusions in the absence of leukocytes. Using advanced quantitation of atomic force microscopy (AFM) recordings, we found these structures to protrude by 160 ± 80 nm above endothelial surface level. Confocal immunofluorescence microscopy proved them positive for ICAM-1, JAM-A, tetraspanin CD9 and f-actin. Microvilli formation was inhibited in the absence of CD9. Our findings indicate that stimulation with TNF-α induces nanoscale changes in endothelial surface architecture and that—via a tetraspanin CD9 depending mechanism—the EAPs rise above the surface to facilitate leukocyte capture
Examiner effect on the objective structured clinical exam – a study at five medical schools
Background: The Objective Structured Clinical Examination (OSCE) is increasingly used at medical schools to assess practical competencies. To compare the outcomes of students at different medical schools, we introduced standardized OSCE stations with identical checklists. Methods: We investigated examiner bias at standardized OSCE stations for knee- and shoulder-joint examinations, which were implemented into the surgical OSCE at five different medical schools. The checklists for the assessment consisted of part A for knowledge and performance of the skill and part B for communication and interaction with the patient. At each medical faculty, one reference examiner also scored independently to the local examiner. The scores from both examiners were compared and analysed for inter-rater reliability and correlation with the level of clinical experience. Possible gender bias was also evaluated. Results: In part A of the checklist, local examiners graded students higher compared to the reference examiner; in part B of the checklist, there was no trend to the findings. The inter-rater reliability was weak, and the scoring correlated only weakly with the examiner’s level of experience. Female examiners rated generally higher, but male examiners scored significantly higher if the examinee was female. Conclusions: These findings of examiner effects, even in standardized situations, may influence outcome even when students perform equally well. Examiners need to be made aware of these biases prior to examining
Mutations in GDF5 Reveal a Key Residue Mediating BMP Inhibition by NOGGIN
Signaling output of bone morphogenetic proteins (BMPs) is determined by two sets of opposing interactions, one with heterotetrameric complexes of cell surface receptors, the other with secreted antagonists that act as ligand traps. We identified two mutations (N445K,T) in patients with multiple synostosis syndrome (SYM1) in the BMP–related ligand GDF5. Functional studies of both mutants in chicken micromass culture demonstrated a gain of function caused by a resistance to the BMP–inhibitor NOGGIN and an altered signaling effect. Residue N445, situated within overlapping receptor and antagonist interfaces, is highly conserved among the BMP family with the exception of BMP9 and BMP10, in which it is substituted with lysine. Like the mutant GDF5, both BMPs are insensitive to NOGGIN and show a high chondrogenic activity. Ectopic expression of BMP9 or the GDF5 mutants resulted in massive induction of cartilage in an in vivo chick model presumably by bypassing the feedback inhibition imposed by endogenous NOGGIN. Swapping residues at the mutation site alone was not sufficient to render Bmp9 NOG-sensitive; however, successive introduction of two additional substitutions imparted high to total sensitivity on customized variants of Bmp9. In conclusion, we show a new mechanism for abnormal joint development that interferes with a naturally occurring regulatory mechanism of BMP signaling
- …