1,911 research outputs found
Sexual dysfunction in first-episode schizophrenia patients: results from European First Episode Schizophrenia Trial
Sexual dysfunctions (SDs) occur frequently in schizophrenia patients and have a huge impact on quality of life and compliance. They are often associated with antipsychotic medication. Nicotine consumption, negative or depressive symptoms, and physical illness are also discussed as contributing factors. Data on SD in first-episode schizophrenia patients are scarce.As part of the European First Episode Schizophrenia Trial, first-episode schizophrenia patients were randomly assigned to 5 medication groups. We assessed SD by analyzing selected items from the Udvalg for Kliniske Undersugelser at baseline and at 5 following visits.Differences between antipsychotics were small for all SDs, and fairly little change in the prevalence of SDs was seen over the course of the study. A significantly larger increase of amenorrhea and galactorrhea was seen with amisulpride than with the other medications. In men, higher age, more pronounced Positive and Negative Syndrome Scale general psychopathology symptoms, and higher plasma prolactin levels predicted higher rates of erectile and ejaculatory dysfunctions. Positive and Negative Syndrome Scale negative symptoms and higher age were predictors for decreased libido.In women, higher prolactin plasma levels were identified as a predictor of amenorrhea. Positive and Negative Syndrome Scale negative symptoms predicted decreased libido.All evidence taken together underscores the influence of the disease schizophrenia itself on sexual functioning. In addition, there is a strong correlation between the prolactin-increasing properties of amisulpride and menstrual irregularities
Smoothed Particle Hydrodynamics partikelbasierte Strömungsberechnung zur Anwendung in der Siedlungswasserwirtschaft
Zahlreiche Strömungsprobleme in der Siedlungswasserwirtschaft können mittels vereinfachter Methoden berechnet werden. Zum Beispiel werden Reaktoren meist als voll durchmischt angenommen und Gerinneströmungen durch ein eindimensionales Modell approximiert. Beeinflusst aber die Strömung die Funktion der Infrastruktur, ist es notwendig, komplexere numerische Berechnungen mit Computational-Fluid-Dynamics-Methoden durchzuführen. Beispiele dafür sind die Modellierung von Absetzbecken, Faulbehältern und komplexen Mischwasserbehandlungsanlagen. Numerische Strömungsberechnungen in der Siedlungswasserwirtschaft verwenden bislang gitterbasierte Computational-Fluid-Dynamics-Methoden. In diesem Artikel wird anhand von Beispielen die Anwendungsmöglichkeit einer alternativen partikelbasierten Methode, nämlich von Smoothed Particle Hydrodynamics, diskutiert.Many of the fluid dynamics problems involved in sanitary engineering can be calculated with the help of simplified methods. For example, reactors are most often assumed to be fully mixed and open-channel flows are approximated using a one-dimensional model. If the flows influence the function of the infrastructure, however, it becomes necessary to carry out more complex numerical calculations using Computational Fluid Dynamics (CFD) methods; examples include the modeling of sedimentation tanks, digesters and complex mixed water treatment facilities. To date, numerical calculations in sanitary engineering have used grid-based CFD methods. The following article discusses the potential applications of an alternative particle-based method, Smoothed Particle Hydrodynamics, on the basis of practical examples.(VLID)899113Version of recor
Improved accuracy of continuum surface flux models for metal additive manufacturing melt pool simulations
Computational modeling of the melt pool dynamics in laser-based powder bed fusion metal additive manufacturing (PBF-LB/M) promises to shed light on fundamental mechanisms of defect generation. These processes are accompanied by rapid evaporation so that the evaporation-induced recoil pressure and cooling arise as major driving forces for fluid dynamics and temperature evolution. The magnitude of these interface fluxes depends exponentially on the melt pool surface temperature, which, therefore, has to be predicted with high accuracy. The present work utilizes a diffuse interface finite element model based on a continuum surface flux (CSF) description of interface fluxes to study dimensionally reduced thermal two-phase problems representative for PBF-LB/M in a finite element framework. It is demonstrated that the extreme temperature gradients combined with the high ratios of material properties between metal and ambient gas lead to significant errors in the interface temperatures and fluxes when classical CSF approaches, along with typical interface thicknesses and discretizations, are applied. It is expected that this finding is also relevant for other types of diffuse interface PBF-LB/M melt pool models. A novel parameter-scaled CSF approach is proposed, which is constructed to yield a smoother temperature field in the diffuse interface region, significantly increasing the solution accuracy. The interface thickness required to predict the temperature field with a given level of accuracy is less restrictive by at least one order of magnitude for the proposed parameter-scaled approach compared to classical CSF, drastically reducing computational costs. Finally, we showcase the general applicability of the parameter-scaled CSF to a 3D simulation of stationary laser melting of PBF-LB/M considering the fully coupled thermo-hydrodynamic multi-phase problem, including phase change
Rekonstruktion großer osteochondraler Defekte des distalen Femurs und der proximalen Tibia
The reconstruction of large osteochondral defects is still a challenge in musculoskeletal surgery. Fresh frozen allografts are a frequently used resource for the treatment of such tissue defects. Furthermore, 3D-printed models enable multiple options in the preoperative planning and intraoperative adaptation of the allografts, so that healing is optimal and the best functional outcome for the patient is achieved.Die Rekonstruktion großer osteochondraler Defekte stellt nach wie vor eine Herausforderung in der muskuloskeletalen Chirurgie dar. Frisch gefrorene Allografts sind eine häufig genutzte Ressource für die Behandlung solcher Gewebedefekte. Darüber hinaus ermöglichen 3D-gedruckte Kunststoffmodelle vielfältige Optionen in der präoperativen Planung und bei der intraoperativen Anpassung der Transplantate, sodass sie optimal einheilen und das bestmögliche funktionelle Ergebnis für den Patienten erreicht wird
Inflammatory tissue response in human soft tissue is caused by a higher particle load near carbon fiber-reinforced PEEK compared to titanium plates
Titanium as the leading implant material in locked plating is challenged by polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK), which became the focus of interest of researchers and manufacturers in recent years. However, data on human tissue response to these new implant materials are rare. Osteosynthesis plates and peri–implant soft tissue samples of 16 healed proximal humerus fractures were examined (n = 8 CFR-PEEK, n = 8 titanium). Soft tissue was analyzed by immunohistochemistry and μCT. The entrapped foreign bodies were further examined for their material composition by FTIR. To gain insight into their origin and formation mechanism, explanted and new plates were evaluated by SEM, EDX, profilometry and HR-CT. In the peri–implant soft tissue of the CFR-PEEK plates, an inflammatory tissue reaction was detected. Tissues contained foreign bodies, which could be identified as tantalum wires, carbon fiber fragments and PEEK particles. Titanium particles were also found in the peri–implant soft tissue of the titanium plates but showed a less intense surrounding tissue inflammation in immunohistochemistry. The surface of explanted CFR-PEEK plates was rougher and showed exposed and broken carbon fibers as well as protruding and deformed tantalum wires, especially in used screw holes, whereas scratches were identified on the titanium plate surfaces. Particles were present in the peri–implant soft tissue neighboring both implant materials and could be clearly assigned to the plate material. Particles from both plate materials caused detectable tissue inflammation, with more inflammatory cells found in soft tissue over CFR-PEEK plates than over titanium plates
AI-based prediction of depression symptomatology in first-episode psychosis patients: insights from the EUFEST and RAISE-ETP clinical trials
Background: Depressive symptoms are highly prevalent in first-episode psychosis (FEP) and worsen clinical outcomes. It is currently difficult to determine which patients will have persistent depressive symptoms based on a clinical assessment. We aimed to determine whether depressive symptoms and post-psychotic depressive episodes can be predicted from baseline clinical data, quality of life, and blood-based biomarkers, and to assess the geographical generalizability of these models. Methods: Two FEP trials were analyzed: European First-Episode Schizophrenia Trial (EUFEST) (n = 498; 2002–2006) and Recovery After an Initial Schizophrenia Episode Early Treatment Program (RAISE-ETP) (n = 404; 2010–2012). Participants included those aged 15–40 years, meeting Diagnostic and Statistical Manual of Mental Disorders IV criteria for schizophrenia spectrum disorders. We developed support vector regressors and classifiers to predict changes in depressive symptoms at 6 and 12 months and depressive episodes within the first 6 months. These models were trained in one sample and externally validated in another for geographical generalizability. Results: A total of 320 EUFEST and 234 RAISE-ETP participants were included (mean [SD] age: 25.93 [5.60] years, 56.56% male; 23.90 [5.27] years, 73.50% male). Models predicted changes in depressive symptoms at 6 months with balanced accuracy (BAC) of 66.26% (RAISE-ETP) and 75.09% (EUFEST), and at 12 months with BAC of 67.88% (RAISE-ETP) and 77.61% (EUFEST). Depressive episodes were predicted with BAC of 66.67% (RAISE-ETP) and 69.01% (EUFEST), showing fair external predictive performance. Conclusions: Predictive models using clinical data, quality of life, and biomarkers accurately forecast depressive events in FEP, demonstrating generalization across populations
Multivariable prediction of functional outcome after first-episode psychosis:a crossover validation approach in EUFEST and PSYSCAN
Several multivariate prognostic models have been published to predict outcomes in patients with first episode psychosis (FEP), but it remains unclear whether those predictions generalize to independent populations. Using a subset of demographic and clinical baseline predictors, we aimed to develop and externally validate different models predicting functional outcome after a FEP in the context of a schizophrenia-spectrum disorder (FES), based on a previously published cross-validation and machine learning pipeline. A crossover validation approach was adopted in two large, international cohorts (EUFEST, n = 338, and the PSYSCAN FES cohort, n = 226). Scores on the Global Assessment of Functioning scale (GAF) at 12 month follow-up were dichotomized to differentiate between poor (GAF current < 65) and good outcome (GAF current ≥ 65). Pooled non-linear support vector machine (SVM) classifiers trained on the separate cohorts identified patients with a poor outcome with cross-validated balanced accuracies (BAC) of 65-66%, but BAC dropped substantially when the models were applied to patients from a different FES cohort (BAC = 50-56%). A leave-site-out analysis on the merged sample yielded better performance (BAC = 72%), highlighting the effect of combining data from different study designs to overcome calibration issues and improve model transportability. In conclusion, our results indicate that validation of prediction models in an independent sample is essential in assessing the true value of the model. Future external validation studies, as well as attempts to harmonize data collection across studies, are recommended.</p
Symptom Remission and Brain Cortical Networks at First Clinical Presentation of Psychosis: The OPTiMiSE Study
Individuals with psychoses have brain alterations, particularly in frontal and temporal cortices, that may be particularly prominent, already at illness onset, in those more likely to have poorer symptom remission following treatment with the first antipsychotic. The identification of strong neuroanatomical markers of symptom remission could thus facilitate stratification and individualized treatment of patients with schizophrenia. We used magnetic resonance imaging at baseline to examine brain regional and network correlates of subsequent symptomatic remission in 167 medication-naïve or minimally treated patients with first-episode schizophrenia, schizophreniform disorder, or schizoaffective disorder entering a three-phase trial, at seven sites. Patients in remission at the end of each phase were randomized to treatment as usual, with or without an adjunctive psycho-social intervention for medication adherence. The final follow-up visit was at 74 weeks. A total of 108 patients (70%) were in remission at Week 4, 85 (55%) at Week 22, and 97 (63%) at Week 74. We found no baseline regional differences in volumes, cortical thickness, surface area, or local gyrification between patients who did or did not achieved remission at any time point. However, patients not in remission at Week 74, at baseline showed reduced structural connectivity across frontal, anterior cingulate, and insular cortices. A similar pattern was evident in patients not in remission at Week 4 and Week 22, although not significantly. Lack of symptom remission in first-episode psychosis is not associated with regional brain alterations at illness onset. Instead, when the illness becomes a stable entity, its association with the altered organization of cortical gyrification becomes more defined
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