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In this Paper, the integrated propeller-wing system design space is investigated to gain insight into the influence of propeller diameter, location, and rotation direction. To conduct this investigation, a methodology is developed that uses the propeller power required during steady-level flight as a metric for efficiency. Full mutual interaction between the propeller and wing are taken into account in the aerodynamic analysis. To ensure that the propeller is not operating off design, it is designed within an iterative trim loop. This approach is then used to investigate the theory that an inboard-up rotating propeller located at the wing tip is the most aerodynamically efficient configuration through the use of a test case. When considering the trimmed propeller power required, the trends for this case indicate that the optimal propeller for this planform is not an inboard-up rotating propeller at the wing tip, but instead is an inboard-down rotating propeller near the root of the wing. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) during alkaline water electrolysis is the bottleneck of water splitting. Perovskite materials have been particularly proposed as good and economically reasonable electrocatalysts for the OER, showing promise and advantages with respect to classic metallic electrodes. However, the degradation of perovskites during catalysis limits their service lifetime. Recently, the material BaCo0.98Ti0.02O3−δ:Co3O4 was shown to be electrocatalytically and chemically stable during water electrolysis even under industrially relevant conditions. The lifetime of this perovskite-based system is prolonged by a factor of 10 in comparison to that of Pr0.2Ba0.8CoO3−δ and is comparable to that of industrially applied electrodes. Here we report on the degradation kinetics of several OER catalysts at room temperature, comparatively studied by monitoring the oxygen evolution at microelectrodes. A decrease in the reaction rate within a maximum of 60 s is observed, which is related to chemical and/or structural changes at the oxide surface. [ABSTRACT FROM AUTHOR]

Hydrocyclones enhance oil–water separation efficiency compared to conventional separation methods. An efficient collision detection scheme withNplnNpdependency on the number of particles is proposed. The scheme is developed to investigate the importance of particle–particle interaction for flow and particle behavior in dilute oil–water separators. However, the proposed scheme can also be used for efficient multigrid soft collision calculation with long-range particle–particle interaction models. The collision detection scheme is first validated using a case of settling spheres. Subsequently, the scheme is applied to a simplified flow field, similar to the flow fields observed in hydrocyclones. [ABSTRACT FROM AUTHOR]

We describe the first case of disseminated infection with Mycobacterium genavense in an HIV-seronegative patient with a chronic haematological disorder. Our patient, an 80-year-old woman, had been under long-term treatment with chlorambucil (partially in combination with prednisone) for B-cell chronic lymphocytic leukaemia (B-CLL). When she developed general fatigue and progressive anaemia, as well as progressive lymphadenopathy and splenomegaly, bone marrow biopsy revealed granulomas with acid-fast bacilli, and cultures of both bone marrow and blood grew M. genavense. The patient's CD4+ cell count was approximately 100 microL(-1). Treatment with clarithromycin, ethambutol and rifabutin resulted in improvement of anaemia and general health as well as in regression of lymphadenopathy and splenomegaly. [ABSTRACT FROM AUTHOR]

Exposure therapy is known to be an effective treatment for anxiety disorders. Nevertheless, exposure is not used as much as it should be, and instead patients are often given supportive medications such as serotonin reuptake inhibitors (SSRIs) and benzodiazepines, which may even interfere with the extinction learning that is the aim of treatment. Given that randomized controlled trials are now investigating a few doses of ±3,4-methylenedioxymethamphetamine (MDMA, 'ecstasy') in combination with psychotherapy for treatment-resistant anxiety disorders, we would like to suggest the following three mechanisms for this potentially important new approach: 1) MDMA increases oxytocin levels, which may strengthen the therapeutic alliance; 2) MDMA increases ventromedial prefrontal activity and decreases amygdala activity, which may improve emotional regulation and decrease avoidance and 3) MDMA increases norepinephrine release and circulating cortisol levels, which may facilitate emotional engagement and enhance extinction of learned fear associations. Thus, MDMA has a combination of pharmacological effects that, in a therapeutic setting, could provide a balance of activating emotions while feeling safe and in control, as described in case reports of MDMA-augmented psychotherapy. Further clinical and preclinical studies of the therapeutic value of MDMA are indicated. [ABSTRACT FROM AUTHOR]

The recovery time of the human eye after a one-second exposure to a foveal glare source was measured for several intensities of test and glare light. The experiment was performed at 475, 500, 550,600 and 650 nm wavelength; the test light and the glare light were of the same wavelength and of constant bandwidth 20 nm. [ABSTRACT FROM PUBLISHER]

The recovery time of the human eye after brief exposures to monochromatic glare was measured as a function of wavelength and exposure time. The test stimulus and the glare stimulus were of the same frequency and bandwidth. The measurements were performed with approximately constant irradiance over the range from 475 nm to 650 nm in steps of 25 nm. [ABSTRACT FROM PUBLISHER]

Non-ischemic dilated cardiomyopathies (DCM) are important causes of heart transplant worldwide. Previous international data suggest that familial etiology for heart failure may be frequently overlooked among patients undergoing heart transplant. A structured screening instrument may help to identify patients who would benefit from genetic testing. Fifty-nine heart transplanted patients from a single transplant center in South of Brazil were reviewed between 2015-2019; those with hypertrophic cardiomyopathies or confirmed ischemic DCM were excluded. Patients with non-ischemic CMP answered a structured screening questionnaire (Kushner et al., 2006), and familial etiology was classified in confirmed, probable, possible familial or non-familial DCM. Thirty-four heart transplant recipients were included (53% male, 85% Caucacian, 50±14 years). Etiologic classification pre and post structured screening is depicted in Figures 1A and 1B. There was a difference in suspected familial etiology pre and post structured screening (15% versus 32%; p = 0.037). These findings suggest that familial DCM is frequently overlooked by the time of heart transplant. Our prevalence of familial DCM is similar to international reports. Applying a structured, low-cost, screening tool may contribute to counseling patients and their relatives regarding special attention to cardiovascular conditions and proper indication of genetic testing in a resource-limited scenario. [ABSTRACT FROM AUTHOR]