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-Three oxalic acid (OA) solutions were applied to 24 honeybee colonies to test acaricidal effects on Varroa destructor. Daily natural mite drop per colony averaged 0.52. Higher mite mortality (18.33) was found after three August OA treatments. The mean efficacy's of the three water solutions of OA/sucrose (w/w), 3.4%/47.6%, 3.7%/26.1%, and 2.9%/31.9% applied in the presence of brood, was 52.28%, 40.66% and 39.16% respectively. A significantly higher efficacy was recorded when 3.4%/47.6% was applied in comparison to 2.9%/31.9% solution. There was no difference in efficacy between OA solutions administered during a broodless period on October 28. The average efficacy in all colonies was 99.44%. The results suggest that OA has limited acaricidal effect in colonies with brood, but it is highly effective in a broodless period.Varroa destructor (jacobsoni) / honeybee / control / oxalic acid /efficacy

X-ray phase contrast imaging is a powerful analysis technique for materials science and biomedicine. Here, we report on laboratory grating-based X-ray interferometry employing a microfocus X-ray source and a high Talbot order (35th) asymmetric geometry to achieve high angular sensitivity and high spatial resolution X-ray phase contrast imaging in a compact system (total length <1 m). The detection of very small refractive angles (∼50 nrad) at an interferometer design energy of 19 keV was enabled by combining small period X-ray gratings (1.0, 1.5 and 3.0 µm) and a single-photon counting X-ray detector (75 µm pixel size). The performance of the X-ray interferometer was fully characterized in terms of angular sensitivity and spatial resolution. Finally, the potential of laboratory X-ray phase contrast for biomedical imaging is demonstrated by obtaining high resolution X-ray phase tomographies of a mouse embryo embedded in solid paraffin and a formalin-fixed full-thickness sample of human left ventricle in water with a spatial resolution of 21.5 µm.

Aims To compare characteristics of left ventricular assist device (LVAD) recipients receiving a cardiac implantable electronic device (CIED) with a defibrillator component (implantable cardioverter‐defibrillator and cardiac resynchronization therapy with defibrillation, CIED‐D) vs. those without one, and to assess whether carrying such a device contiguously with an LVAD is associated with outcomes. Methods and results Overall, 448 patients were analysed (mean age 52 ± 13 years, 82% male) in the multicentre European PCHF‐VAD registry. To account for all active CIED‐Ds during ongoing LVAD treatment, outcome analyses were performed by a time‐varying analysis with active CIED‐D status post‐LVAD as the time‐varying covariate. At the time of LVAD implantation, 235 patients (52%) had an active CIED‐D. Median time on LVAD support was 1.1 years (interquartile range 0.5–2.0 years). A reduction of 36% in the risk of all‐cause mortality was observed in patients with an active CIED‐D [hazard ratio (HR) 0.64, 95% confidence interval (CI) 0.46–0.91; P = 0.012), increasing to 41% after adjustment for baseline covariates (HR 0.59, 95% CI 0.40–0.87; P = 0.008) and 39% after propensity score adjustment (HR 0.61, 95% CI 0.39–0.94; P = 0.027). Other than CIED‐D, age, LVAD implant as redo surgery, number of ventricular arrhythmia episodes and use of vasopressors pre‐LVAD were remaining significant risk factors of all‐cause mortality. Incident ventricular arrhythmias post‐LVAD portended a 2.4‐fold and 2.6‐fold increased risk of all‐cause and cardiovascular death, respectively; carrying an active CIED‐D remained associated with a 47% and 43% reduction in these events, respectively. Conclusions In an analysis accounting for all active CIED‐Ds, including those implanted during LVAD support, carrying such a device was associated with significantly better survival during LVAD support.