Stereoscopic motion analysis in densely packed clusters: 3D analysis of the shimmering behaviour in Giant honey bees

<p>Abstract</p> <p>Background</p> <p>The detailed interpretation of mass phenomena such as human escape panic or swarm behaviour in birds, fish and insects requires detailed analysis of the 3D movements of individual participants. Here, we describe the adaptation of a 3D stereoscopic imaging method to measure the positional coordinates of individual agents in densely packed clusters. The method was applied to study behavioural aspects of shimmering in Giant honeybees, a collective defence behaviour that deters predatory wasps by visual cues, whereby individual bees flip their abdomen upwards in a split second, producing Mexican wave-like patterns.</p> <p>Results</p> <p>Stereoscopic imaging provided non-invasive, automated, simultaneous, <it>in-situ </it>3D measurements of hundreds of bees on the nest surface regarding their thoracic position and orientation of the body length axis. <it>Segmentation </it>was the basis for the <it>stereo matching</it>, which defined correspondences of individual bees in pairs of stereo images. Stereo-matched "agent bees" were re-identified in subsequent frames by the <it>tracking </it>procedure and <it>triangulated </it>into real-world coordinates. These algorithms were required to calculate the three spatial motion components (dx: horizontal, dy: vertical and dz: towards and from the comb) of individual bees over time.</p> <p>Conclusions</p> <p>The method enables the assessment of the 3D positions of individual Giant honeybees, which is not possible with single-view cameras. The method can be applied to distinguish at the individual bee level active movements of the thoraces produced by abdominal flipping from passive motions generated by the moving bee curtain. The data provide evidence that the z-deflections of thoraces are potential cues for colony-intrinsic communication. The method helps to understand the phenomenon of collective decision-making through mechanoceptive synchronization and to associate shimmering with the principles of wave propagation. With further, minor modifications, the method could be used to study aspects of other mass phenomena that involve active and passive movements of individual agents in densely packed clusters.</p

Systematic Association Mapping Identifies NELL1 as a Novel IBD Disease Gene

Crohn disease (CD), a sub-entity of inflammatory bowel disease (IBD), is a complex polygenic disorder. Although recent studies have successfully identified CD-associated genetic variants, these susceptibility loci explain only a fraction of the heritability of the disease. Here, we report on a multi-stage genome-wide scan of 393 German CD cases and 399 controls. Among the 116,161 single-nucleotide polymorphisms tested, an association with the known CD susceptibility gene NOD2, the 5q31 haplotype, and the recently reported CD locus at 5p13.1 was confirmed. In addition, SNP rs1793004 in the gene encoding nel-like 1 precursor (NELL1, chromosome 11p15.1) showed a consistent disease-association in independent German population- and family-based samples (942 cases, 1082 controls, 375 trios). Subsequent fine mapping and replication in an independent sample of 454 French/Canadian CD trios supported the authenticity of the NELL1 association. Further confirmation in a large German ulcerative colitis (UC) sample indicated that NELL1 is a ubiquitous IBD susceptibility locus (combined p<10−6; OR = 1.66, 95% CI: 1.30–2.11). The novel 5p13.1 locus was also replicated in the French/Canadian sample and in an independent UK CD patient panel (453 cases, 521 controls, combined p<10−6 for SNP rs1992660). Several associations were replicated in at least one independent sample, point to an involvement of ITGB6 (upstream), GRM8 (downstream), OR5V1 (downstream), PPP3R2 (downstream), NM_152575 (upstream) and HNF4G (intron)

Umfrage: Situation der Hochschuldidaktik in Deutschland

Ergebnisse der Umfrage zur Situation der Hochschuldidaktik in Deutschland. Befragung der Zuständigen für Hochschuldidaktik

Lanthanide luminescence from supramolecular hydrogels consisting of bio-conjugated picolinic-acid-based guanosine quadruplexes

The formation of bio-inspired healable lanthanide luminescent hydrogels is detailed. These materials are composed of K(I)-stabilized guanosine quadruplexes (G4) that were bio-conjugated to mannose-derived picolinic acid ligand 1 using boric acid chemistry (G4-1). The supramolecular self-assembly between G4-1 and europium (Eu(III)) was confirmed, including the use of time-gated luminescence spectroscopy. The most stable hydrogel was formed when the ratio between 1 and Eu(III) was 1:1, and this gel was found to retain a helical column. The obtained gel samples were further characterized using techniques, such as scanning electron microscopy (SEM), circular dichroism (CD), and luminescence spectroscopy. We demonstrate that a Eu(III)-centered circularly polarized luminescence (CPL) signal from guanosine hydrogels can be observed even via long-range interaction, whereas the rheology of these gels exhibits their healable properties

Attitude towards adherence in patients with schizophrenia at discharge

Background: Purpose of the present study was to assess the attitude towards adherence at discharge and to verify its predictability using anamnestic and sociodemographic variables. factors influencing clinical treatment as well as the medical treatment applied. Methods: Attitude towards adherence was evaluated in 369 inpatients with schizophrenic spectrum disorders within a naturalistic multicenter trial using the Compliance Rating Scale (CRS) by Kemp. Biweekly ratings of the PANSS, UKU and the Subjective Well-being under Neuroleptic Treatment Scale (SWN-K) were applied. Logistic regression and CART analyses were used to determine significant predictor variables for the attitude towards adherence at discharge. Results: Sixty-seven percent of the patients were rated to have an attitude of active participation and moderate participation (=positive attitude towards adherence) and 33% of the patients to have an attitude of passive acceptance, occasional or permanent reluctance towards treatment as well as refusing treatment (=negative attitude towards adherence). A significant correlation was found between patients with a positive attitude towards adherence and course of all PANSS subscales. Statistical analyses revealed a reduction in PANSS general psychopathology subscore, employment status, greater illness insight and treatment with atypical antipsychotics to be significantly predictive for a positive attitude towards adherence at discharge. Conclusions: The importance of an adequate antipsychotic treatment as a precondition for a favourable adherence attitude and the need to incorporate adherence-focused psychotherapy and psychoeducation into daily clinical practice are highlighted. (C) 2009 Elsevier Ltd. All rights reserved.German Federal Ministry for Education and Research BMBF [01 GI 0233

Defining and predicting functional outcome in schizophrenia and schizophrenia spectrum disorders

Background: To assess criteria and to identify predictive factors for functional outcome. The criteria should cover all domains proposed by the Remission in Schizophrenia Working Group. Method: PANSS ratings were used to evaluate the symptomatic treatment outcome of 262 inpatients with schizophrenia spectrum disorders within a naturalistic multicenter trial. Functional remission was defined as a GAF score >61 (Global Assessment of Functioning Scale), SOFAS score >61 (Social and Occupational Functioning Scale) and a SF-36 mental health subscore >40 (Medical Outcomes Study-Short Form Health Survey). Multivariate logistic regression and CART analyses were used to determine valid clinical and sociodemographic predictors. Results: In total, 52 patients (20%) fulfilled the criteria for functional remission, 125 patients (48%) achieved symptomatic resolution and when criteria for functional remission and symptomatic resolution were combined 33 patients (13%) achieved complete remission. Younger age, employment, a shorter duration of illness, a shorter length of current episode, less suicidality, and a lower PANSS negative and global subscore at admission were predictive of functional remission. The regression model showed a predictive value of more than 80%. Conclusions: A significant association was found between functional remission and symptomatic resolution, indicating reasonable validity of the proposed definition for functional outcome. The revealed predictors for functional treatment outcome emphasize the need for psychosocial and vocational rehabilitation in schizophrenic patients. (C) 2009 Elsevier B.V. All rights reserved.German Federal Ministry for Education and Research BMBF [01 GI 0233

What are residual symptoms in schizophrenia spectrum disorder? Clinical description and 1-year persistence within a naturalistic trial

The aim of this study was to evaluate residual symptoms in patients achieving remission according to the consensus criteria and to analyze their potential influence on the patient's outcome one year after discharge. In total, 399 patients suffering from a schizophrenia spectrum disorder were evaluated within a naturalistic study. Remission status was examined using the consensus criteria. Residual symptoms were defined as any symptom present at the time-point of remission following analogous analyses performed in depressed patients. Therefore, a PANSS item with a symptom severity of > 1 (= at least borderline mentally ill) was defined to be a residual symptom. Remitters with and without residual symptoms were compared regarding psychopathology, functioning and side effects. In total, 236 patients (59 %) were remitters at discharge with 94 % of them suffering from at least one residual symptom. The most common residual symptoms were blunted affect (49 %), conceptual disorganization (42 %) and social withdrawal (40 %). A significant association was found between the presence of residual symptoms and the severity of side effects (p < 0.0001) and functioning (p = 0.0003) at discharge as well as between residual symptoms and the risk of relapse and chance of remission one year after discharge. Residual symptoms were highly prevalent in remitted schizophrenia inpatients following the suggested definition. Most residual symptoms were persistent baseline symptoms suggesting an ongoing illness severity. Also, the necessity to re-evaluate the consensus criteria questioning the status of remission in these patients is also pointed out

Influencing factors and predictors of early improvement in the acute treatment of schizophrenia and schizophrenia spectrum disorder

Background: To examine the influencing factors and predictors of early improvement in schizophrenia patients. Methods: 370 patients suffering from a schizophrenia spectrum disorder were examined within a naturalistic multicenter study. Early improvement was defined as a >= 30% PANSS total score reduction within the first two treatment weeks, response as a >= 50% improvement of the PANSS total score from admission to discharge and remission according to the consensus, remission criteria. Baseline and course-related variables such as positive, negative and depressive symptoms, side effects, functioning and subjective well-being were examined regarding their explanatory value for early improvement. Results: 46% of the patients were identified to be early improvers. Of these, 77% became treatment responder at discharge and 74% achieved the consensus remission criteria. Amongst others, early improvers were significantly more often first-episode patients (p = 0.009), with a significantly shorter duration of current episode (p = 0.024) and a shorter duration of the illness (p = 0.0094). A higher PANSS positive subscore (p = 0.0089), a higher score in the Strauss-Carpenter-Prognostic Scale (SCPS) (p < 0.0001), less extrapyramidal side effects (p = 0.0004) at admission and the development of less extrapyramidal side effects within the first two treatment weeks (p = 0.0013) as well as a duration of current episode of <= 6 months (p = 0.0373) were identified to be significant predictors of early improvement. Conclusion: Early improvement is associated with less illness chronicity and seems to be independent of the type of antipsychotic and the antipsychotic dosage applied. The SCPS was found to be a valuable tool to detect early improvers already at the initiation of antipsychotic treatment. (C) 2011 Elsevier Ltd. All rights reserved

Does Clinical Judgment of Baseline Severity and Changes in Psychopathology Depend on the Patient Population? Results of a CGI and PANSS Linking Analysis in a Naturalistic Study

Background: Linking of the Clinical Global Impression (CGI) Scale and the Positive and Negative Syndrome Scale (PANSS) was performed within a naturalistic sample. Furthermore, these linking results were compared with those derived from randomized controlled trials to examine if the baseline severity might influence the linking results. Methods: Biweekly PANSS and CGI ratings were performed from admission to discharge in 398 schizophrenia patients treated within a naturalistic study. Equipercentile linking was performed using the statistical program, R 2.8.1. To evaluate how the naturalistic study design would influence linkage results, a so-called study sample was computed with patients of the naturalistic study fulfilling common inclusion criteria of randomized controlled trials (n = 199). Patients not fulfilling these criteria (less ill sample) and those fulfilling the criteria (study sample) were compared using confidence intervals. Results: We found a considerable difference between the linking of the CGI severity score and the PANSS total score comparing the less ill sample and the study sample. Being considered mildly ill'' at admission in the less ill sample corresponded to a PANSS total score of 47 points and to a PANSS total score of 67 points in the study sample. Considering the linking of the CGI improvement score and PANSS changes, similar results were found for CGI improvement ratings ranging from very much improved'' to minimally improved.'' Conclusions: Despite considerable differences, a 50% PANSS reduction was found to correspond to a clinical rating of much improved, which seems to be a suitable definition for response in clinical drug trials