Two-dimensional speckle tracking echocardiography in fetuses with critical aortic stenosis before and after fetal aortic valvuloplasty.

BACKGROUND: Critical aortic stenosis (AS) in fetuses may progress to hypoplastic left heart syndrome (HLHS) with need for postnatal single ventricular (SV) palliation. Fetal aortic valvuloplasty (FAV) is performed to achieve postnatal biventricular (BV) circulation. However, the impact of FAV on fetal myocardial function is difficult to measure. Prediction of postnatal circulatory status and, therefore, counseling is challenging. METHODS: Retrospective study of fetuses with critical AS who underwent FAV. Global Longitudinal Peak Systolic Strain (GLPSS) of the left ventricle (LV) and right ventricle (RV) were retrospectively analyzed before and after intervention. Fisher's Exact Test and Mann-Whitney-U Test were used for univariant statistical analysis. RESULTS: 23 fetuses with critical AS were included. After intervention fetuses demonstrated more negative LV-GLPSS mean values post- vs. pre-intervention (- 5.36% vs. - 1.57%; p < 0.05). RV-GLPSS was decreased in all fetuses, there was no peri-interventional change. 20 fetuses were born alive. Postnatally, 10 had BV and 10 SV circulation. Improved post-interventional LV-GLPSS strain values correlated with BV outcome (p < 0.05). Pre-interventional continuous LV-GLPSS values correlated with postnatal SV vs. BV outcome (p < 0.05). CONCLUSION: In some fetuses, LV myocardial function assessed by speckle tracking echocardiography (STE) improves after FAV. Improved post-interventional LV-GLPSS correlates with biventricular postnatal outcome. Furthermore, pre-interventional LV- and RV-GLPSS correlate with postnatal outcome. Further studies are needed to asses, if pre-interventional STE parameters might predict which fetuses will benefit from FAV with postnatal BV circulation.

Computer-based analysis of the taper connection strength of different revision head and adapter sleeve designs.

OBJECTIVES: Ceramic revision heads, equipped with titanium adapter sleeves, are used in femoral head revision in total hip arthroplasty to avoid ceramic fracture due to the damaged taper. METHODS: A finite element analysis of the taper connection strength of revision heads with varying head diameters combined with adapter sleeves of different lengths was conducted. The influence of various assembly forces, head diameter, and length of the adapter sleeves was evaluated. For two combinations, the pattern of contact pressure was evaluated when applying a simplified joint load (3 kN, 45° load angle). Experimental validation was conducted with 36 mm heads and adapter sleeves in size S, as well as 28 mm heads and adapter sleeves in size XL. RESULTS: The pull-off force increased with higher assembly forces. Using larger head diameters and adapter sleeves led to decreased pull-off forces, a reduced contact surface, and less contact pressure. The contact pressure showed significant peaks and a diagonal pattern under 45° angle loading when assembly forces were less than 4 kN, and larger adapter sleeves were utilized. CONCLUSION: A sufficient assembly force should be ensured intraoperatively, especially with an increasing head diameter and adapter sleeve size, as lower assembly forces might lead to reduced taper connection strength.

Graphene-Enhanced UV-C LEDs.

Light-emitting diodes in the UV-C spectral range (UV-C LEDs) can potentially replace bulky and toxic mercury lamps in a wide range of applications including sterilization and water purification. Several obstacles still limit the efficiencies of UV-C LEDs. Devices in flip-chip geometry suffer from a huge difference in the work functions between the p-AlGaN and high-reflective Al mirrors, whereas the absence of UV-C transparent current spreading layers limits the development of UV-C LEDs in standard geometry. Here it is demonstrated that transfer-free graphene implemented directly onto the p-AlGaN top layer by a plasma enhanced chemical vapor deposition approach enables highly efficient 275 nm UV-C LEDs in both, flip-chip and standard geometry. In flip-chip geometry, the graphene acts as a contact interlayer between the Al-mirror and the p-AlGaN enabling an external quantum efficiency (EQE) of 9.5% and a wall-plug efficiency (WPE) of 5.5% at 8 V. Graphene combined with a ≈1 nm NiOx support layer allows a turn-on voltage <5 V. In standard geometry graphene acts as a current spreading layer on a length scale up to 1 mm. These top-emitting devices exhibit a EQE of 2.1% at 8.7 V and a WPE of 1.1%.

Progress and Challenges of InGaN/GaN-Based Core-Shell Microrod LEDs.

LEDs based on planar InGaN/GaN heterostructures define an important standard for solid-state lighting. However, one drawback is the polarization field of the wurtzite heterostructure impacting both electron-hole overlap and emission energy. Three-dimensional core-shell microrods offer field-free sidewalls, thus improving radiative recombination rates while simultaneously increasing the light-emitting area per substrate size. Despite those promises, microrods have still not replaced planar devices. In this review, we discuss the progress in device processing and analysis of microrod LEDs and emphasize the perspectives related to the 3D device architecture from an applications point of view.

Differential effects of childhood abuse and neglect: mediation by posttraumatic distress in neurotic disorder and negative symptoms in schizophrenia?

Dissociation, though understood as a response to trauma, lacks a proven etiology. The assumption of a dose-response relationship between trauma, dissociation and Schneiderian symptoms led to the proposal of a dissociative subtype of schizophrenia characterized by severe child maltreatment, dissociation and psychosis. Child maltreatment and dissociation are common features of neurotic disorders as well, and the link between trauma, dissociation, and hallucinations is not specific for schizophrenia. This study compares childhood abuse and neglect, posttraumatic distress and adult dissociation in patients with psychotic vs. non-psychotic disorder. Thirty-five participants with non-psychotic disorder and twenty-five with schizophrenia were analyzed using the Scale for the Assessment of Positive Symptoms (SAPS), the Scale for the Assessment of Negative Symptoms (SANS), the Montgomery-Åsberg Depression Rating Scale (MADRS), the Posttraumatic Stress Diagnostic Scale PDS (PDS), the Childhood Trauma Questionnaire (CTO) and the Arbeitsgemeinschaft Methodik und Dokumentation in der Psychiatrie (AMDP)-module on dissociation. Trauma and clinical syndromes were compared by means of T-testing and logistic regression between 1) the diagnoses and 2) groups with and without post-traumatic stress disorder (PTSD), marked dissociation and psychotic symptoms. While non-psychotic disorder was related to abuse, schizophrenia showed an association with neglect. Childhood trauma predicted posttraumatic symptomatology and negative symptoms. Childhood abuse and neglect may effectuate different outcomes in neurotic and psychotic disorder. The underlying mechanisms, including dissociation, dovetail with cognitive, emotional and behavioural changes involved in depression, posttraumatic distress and chronic schizophrenia symptoms rather than being directly linked to trauma.

Disease burden, disease manifestations and current treatment regimen of the SAPHO syndrome in Germany: results from a nationwide patient survey.

BACKGROUND: Due to diagnostic and therapeutic advances, quality of life of patients with spondyloarthritides (SpA) has improved substantially in recent years. However, little is known about how patients with the SAPHO syndrome, a heterogeneous disease counted among the SpAs, profit from these advances. OBJECTIVE: To investigate current aspects of patient care in a nationwide SAPHO cohort. METHODS: Patients were recruited in a university centre and via a nationwide SAPHO patient support group. Medical records were reviewed and patients were asked to complete a questionnaire on the course of diagnosis, disease burden and treatment regimen. RESULTS: A total of 64 patients were included in the analysis. The mean time from disease onset to diagnosis was 3.8 ± 5.3 years. The patients' overall satisfaction with the course of diagnosis was 23.0 ± 28.9 on a visual analogue scale (VAS) from 0 to 100. Musculoskeletal symptoms had the highest impact on the patients' wellbeing. The mean overall disease burden on a VAS for pain was 45.4 ± 25.9. Limitations in the quality of life were reported mainly in the general health, bodily pain and vitality dimensions of the SF-36 questionnaire. Current treatments consisted of NSAIDs (77%), DMARDs (27%), glucocorticoids (23%), TNF-inhibitors (16%) and bisphosphonates (11%). CONCLUSIONS: The SAPHO syndrome has a high impact on the patients' general health and quality of life. Establishing the diagnosis still takes years and expends multiple medical resources. Effective treatments such as TNF-inhibitors are rarely prescribed and current disease burden is not acceptable.

Effect of medication-related factors on adherence in people with schizophrenia: a European multi-centre study.

AIM: To investigate the relation between medication-related factors and adherence in people with schizophrenia in outpatient treatment. METHODS: The sample comprised 409 outpatients (ICD-10 diagnosis of schizophrenia) with clinician-rated instability in four European cities (Amsterdam, The Netherlands; Verona, Italy; Leipzig, Germany; London, Great Britain). Adherence was assessed using the Medication Adherence Questionnaire (patient perspective), and the Clinician Rating Scale (clinician perspective). Examined medication-related factors were type (atypical vs. typical), application (oral vs. depot), daily dose frequency of antipsychotic medication (Medication History Scale), number of side effects (Liverpool University Neuroleptic Side Effect Rating Scale), and patient attitudes toward medication (Drug Attitude Inventory). Multiple regression analysis was used to identify predictors of adherence by medication-related factors. RESULTS: Adherence, as rated by patient and clinician, was predicted by patient attitude towards medication, but was unrelated to type of drug, formulation or side effects of antipsychotic medication. A high daily dose frequency was associated with better adherence, but only when rated by the patient. CONCLUSIONS: In order to improve adherence there is a need to seriously consider and attempt to improve patient attitude toward medication. However, type of antipsychotic and other medication-related factors may not be as closely related to adherence as it has often been suggested.