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In quantum dots (QDs), the Auger recombination is a non-radiative scattering process in which the optical transition energy of a charged exciton (trion) is transferred to an additional electron leaving the dot. Electron tunneling from a reservoir is the competing process that replenishes the QD with an electron again. Here, we study the dependence of the tunneling and Auger recombination rate on the applied electric field using high-resolution time-resolved resonance fluorescence (RF) measurements. With the given p–i–n diode structure and a tunnel barrier between the electron reservoir and the QD of 45 nm, we measured a tunneling rate into the QD in the order of ms−1. This rate shows a strong decrease by almost an order of magnitude for decreasing electric field, while the Auger emission rate decreases by a factor of five in the same voltage range. Furthermore, we study in detail the influence of the Auger recombination and the tunneling rate from the charge reservoir into the QD on the intensity and linewidth of the trion transition. In addition to the well-known quenching of the trion transition, we observe in our time-resolved RF measurements a strong influence of the tunneling rate on the observed linewidth. The steady-state RF measurement yields a broadened trion transition of about 1.5 GHz for an Auger emission rate of the same order as the electron tunneling rate. In a non-equilibrium measurement, the Auger recombination can be suppressed, and a more than four times smaller linewidth of 340 MHz (1.4 μeV) is measured. [ABSTRACT FROM AUTHOR]

The self-consistent electromagnetic integration of tokamak plasma magnetohydrodynamic (MHD) models with external conductors is considered in this manuscript. We integrate the extended MHD code JOREK and the eddy current code CARIDDI, via a scheme based on the virtual casing principle enabling two-way coupled fully implicit simulations. The robustness of this new integrated tool is validated against JOREK-STARWALL and CarMa0NL simulations for vertical displacement events in a simplified ASDEX Upgrade-like geometry and for n = 1 tearing modes in a circular high-aspect-ratio tokamak. The impact of 3D wall structures on the plasma evolution is highlighted introducing ports at different locations of a simplified axisymmetric wall and characterizing its effect on the plasma evolution. In addition to realistically capturing the 3D interactions between plasma and wall structures, the coupled codes will allow in the future 1:1 comparisons to experiments using virtual magnetic diagnostics that capture screening effects accurately. [ABSTRACT FROM AUTHOR]

Summary: Background: Epidermal differentiation is a multilevel process in which keratinocytes need to lose their organelles, including their mitochondria, by autophagy. Disturbed autophagy leads to thickening of the epidermis as seen in pachyonychia congenita (PC), a rare skin disease caused by mutations in keratins 6, 16 and 17. Objectives: To ask if mitophagy, the selective degradation of mitochondria by autophagy, is disturbed in PC and, if so, at which stage. Methods: Immortalized keratinocytes derived from patients with PC were used in fluorescence‐based and biochemical assays to dissect the different steps of mitophagy. Results: PC keratinocytes accumulated old mitochondria and displayed disturbed clearance of mitochondria after mitochondrial uncoupling. However, early mitophagy steps and autophagosome formation were not affected. We observed that autolysosomes accumulate in PC and are not sufficiently recycled. Conclusions: We propose an influence of keratins on autolysosomal degradation and recycling. What's already known about this topic? Terminal epidermal differentiation is a multistep process that includes the elimination of cellular components by autophagy.Autophagy‐impaired keratinocytes have been shown to result in thickening of epidermal layers.Hyperkeratosis also occurs in pachyonychia congenita (PC), a rare skin disease caused by mutations in keratins 6, 16 and 17. What does this study add? Keratins contribute to mitochondrial quality control as well as maintenance of mitochondria–endoplasmic reticulum contact sites.Keratins influence autolysosomal maturation or reformation. What is the translational message? Overaged mitochondria and autolysosomes accumulate in PC.Mutations in keratin 6a lead to severely impaired mitophagy, which might contribute to PC pathogenesis. Linked Comment: Vetter and Magin. Br J Dermatol 2020; 182:529–530. Respond to this article [ABSTRACT FROM AUTHOR]

In this contribution a model for the elastic relaxation of Al0.5 Ga 0.5 As and ZnSe wire structures, respectively, is presented. The wire structures extend along 1¯1 0 and were characterized by high resolution x-ray diffraction experiments. Based on Monte Carlo simulations, the wire structures, which have been simulated at atomic resolution, were relaxed to reduce the strain caused by the lattice misfit. The x-ray diffraction patterns calculated for the final structures reproduce the observed data. The structures display a two dimensional strain gradient and curved lattice planes. Hence the introduced modeling is a powerful method in particular to resolve the atomic structure of a wet chemically etched or molecular beam epitaxial grown wire by giving a microscopic picture on an atomic scale. [ABSTRACT FROM AUTHOR]

Abstract: The potential was modelled of molecular rapid diagnostic tests (RDTs) that target agents of sexually transmitted diseases (STDs) to contribute to a reduction in the exposure risk for sexually active populations who prefer condom‐free high‐risk contacts. The biostatistical approach is exemplified by considering the use of a PCR‐based RDT for Chlamydia trachomatis and Neisseria gonorrhoeae in a population of German men having sex with men. We modelled the exposure risk as risk of sexual contact with individuals infected by a STD in spite of multiple RDTs having been conducted to identify STDs that could lead to avoidance of an infectious sexual contact. The risk for a given specific disease is influenced by the diagnostic accuracy of all diagnostic tests conducted. The simulation showed a reduction in exposure risk through conducting the selected PCR‐based RDT as a strategy to prevent infections with C. trachomatis and N. gonorrhoeae in comparison with unprotected sexual contact of >97% for C. trachomatis and ≥96% for N. gonorrhoeae. Reliable knowledge of the performance characteristics of the diagnostic tests applied is essential for a thorough risk assessment based on such diagnostic approaches. Significance and Impact of the Study: A low‐threshold use of molecular rapid diagnostic tests in settings where risky sexual activity is undertaken with deliberate non‐use of condoms is modelled. Such an approach might contribute to a considerable reduction in the exposure risk if positively tested individuals are excluded from unprotected sexual intercourse. Protective effects are influenced by the prevalence of the disease and the performance characteristics of the applied tests. Precise knowledge of the performance characteristics of the test assays employed are prerequisites of a reliable risk assessment. The modelling approach is of particular use for preventive health experts. [ABSTRACT FROM AUTHOR]

Mutations in SCN2A cause epilepsy syndromes of variable severity including neonatal-infantile seizures. In one case, we previously described additional childhood-onset episodic ataxia. Here, we corroborate and detail the latter phenotype in three further cases. We describe the clinical characteristics, identify the causative SCN2A mutations and determine their functional consequences using whole-cell patch-clamping in mammalian cells. In total, four probands presented with neonatal-onset seizures remitting after five to 13 months. In early childhood, they started to experience repeated episodes of ataxia, accompanied in part by headache or back pain lasting minutes to several hours. In two of the new cases, we detected the novel mutation p.Arg1882Gly. While this mutation occurred de novo in both patients, one of them carries an additional known variant on the same SCN2A allele, inherited from the unaffected father (p.Gly1522Ala). Whereas p.Arg1882Gly alone shifted the activation curve by −4 mV, the combination of both variants did not affect activation, but caused a depolarizing shift of voltage-dependent inactivation, and a significant increase in Na current density and protein production. p.Gly1522Ala alone did not change channel gating. The third new proband carries the same de novo SCN2A gain-of-function mutation as our first published case (p.Ala263Val). Our findings broaden the clinical spectrum observed with SCN2A gain-of-function mutations, showing that fairly different biophysical mechanisms can cause a convergent clinical phenotype of neonatal seizures and later onset episodic ataxia. [ABSTRACT FROM AUTHOR]

Purpose: To assess the risk for technical complications in patients undergoing removal of locking compression plates (LCP) with head locking screws. Methods: A total of 205 patients who were scheduled for implant removal surgery after a healed fracture of the femur, tibia, humerus, distal radius, or clavicle in nine Austrian clinics were prospectively included in the study, all of whom had previously undergone fracture fixation by plates, with titanium implants used in 98 % of the patients. Intraoperative technical complications and the methods used to solve them were documented by the surgeon. Results: During the course of this study, a total of 1,462 locking screws were removed from 204 LCPs. While 95 % of these screws could be removed without difficulties, technical complications were reported for 41 patients with 78 screws which could not be removed with standard screwdrivers and required the use of additional instruments. The estimated risk for the occurrence of at least one technical complication during implant removal surgery was 20.1 %. The most frequently observed complications were screws that could not be loosened because they were jammed in the LCP, screws with a damaged recess in which the screwdriver turned freely, as well as a combination of both events. The majority of these screws could be removed with the use of a conical extraction screw or by drilling off the screw head. In one patient, an intraoperative refracture of the humerus occurred during plate removal. Even though there is a rate of 20 % for technical complications when removing the implants, only a few patients experience a clinical impact. Conclusions: Titanium LCPs are prone to technical complications during implant removal, but the majority of the issues can be solved using special techniques. [ABSTRACT FROM AUTHOR]

Purpose: Since 1992, German soldiers have been deployed in areas where malaria is endemic. Antimalarial chemoprophylaxis (CP) is directed according to the assessed risk and is provided free of charge. Compliance is crucial if its effect is to be reliable. This study analysed compliance with directed CP in German soldiers as well as its determinants. Methods: Between 2003 and 2009, standardized questionnaire-based interviews were performed with 2,149 out of approximately 100,000 German soldiers who were deployed during this period in areas where malaria is endemic. The questionnaires dealt with information that the soldiers had received about malaria prior to their missions, with their adherence to mosquito-protective and antimalarial chemoprophylactic procedures, and their estimations of their individual level of exposure. Results: About 1,308 out of 2,149 interviewed soldiers had been ordered to take CP, allowing for an assessment of the outcome parameter 'CP-compliance'. About 76.9 % out of 1,308 soldiers to whom regular CP was directed took it regularly. The exposure variables 'age', 'satisfaction with malaria counselling', 'perceived threat due to insects or mosquitoes' and 'use of insect repellents' were positively associated with compliance with directed antimalarial CP. Conclusions: The study confirms the findings of the French and US armies that even free-of-charge access to antimalarial medication will not lead to 100 % acceptance. The compliance problem is aggravated by the generally low age of deployed soldiers. Adequate counselling is crucial to increase adherence to antimalarial CP. [ABSTRACT FROM AUTHOR]

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Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Unfallchirurgie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Unlabelled: In a previous study it has been shown that granulae of decalcified bone matrix do not induce bony healing of 8-week-old mid-diaphyseal defects in dogs. The aim of this study was to test whether osteoinduction combined with the osteoconductive mechanisms provided by the natural structure of cancellous bone blocks would yield better results. A 30-mm-long diaphyseal defect of the left ulna was created in eight adult mongrel dogs and the bone was stabilized with a plate. A Silastic spacer was inserted in the defect for 8 weeks, followed by implantation of frozen undecalcified or decalcified allogeneic cancellous bone blocks for 16 weeks. Healing was analyzed using morphologic methods. At 16 weeks after implantation all grafts had been resorbed. In the decalcified group one defect healed, while none in the other group did so. The implant material was bioassayed in nude rats for osteoinductivity, which was found to be low in decalcified matrix and not detectable in undecalcified bone.Conclusion: Allogeneic cancellous bone blocks, demineralized or not, have no osteoinductive capacity and no osteoconductive function that promotes healing of mid-diaphyseal bone defects in dogs. [ABSTRACT FROM AUTHOR]

In postmortem examinations 26 hip joints of 23 adult individuals were filled with Ringer's solution in order to furnish data on the relationship between intra-articular pressure, capsular content, and joint position. A tube system was connected to an 18-gauge needle and to a pressure transducer. After instillation of 2.5, 5.0, 7.5, and 10.0 ml of Ringer's solution, intra-articular pressure was recorded in six different joint positions (extension, 45° and 90° flexion, 40° internal and 40° external rotation, and 45° abduction in extension). Intra-articular pressure depends mainly on the position of the joint, with highest values in external and internal rotation and lowest values in 45° flexion. In this last position, the pressure was zero in two of four cases after injection of 10 ml, whereas with external rotation and instillation of 2.5 ml almost 60 kPa was recorded. In extension and after filling with 10 ml the pressure exceeded the level of normal systolic blood pressure in all cases. Under pathologic conditions intra-articular pressure of the hip joint can rise well above arterial pressure and thus eventually compromise vascular supply to the femoral head, even in the presence of only minimal intra-articular effusion. [ABSTRACT FROM AUTHOR]

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Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary (Three kinds of statistics in physics). A simplified derivation is given of the energy-distribution of Maxwell-Boltzmann, Bose-Einstein and Fermi-Dirac. The importance and the application of these laws are considered, and the fundamental hypotheses, on which they are based are mentioned. It is shown that only one sort of statistics is used, but that the statistical method is adapted in each case to the special physical properties of the particles, to which this method is applied. [ABSTRACT FROM AUTHOR]

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We report on the molecular-beam epitaxial growth and magnetotransport properties of p-type BeMnTe, a ferromagnetic diluted magnetic semiconductor. BeMnTe thin-film structures can be grown almost lattice matched to GaAs for Mn concentrations up to 10%. A high p-type doping with nitrogen can be achieved by using a rf plasma source. BeMnTe and BeTe layers have been characterized by magnetotransport measurements. At low temperatures, the BeMnTe samples exhibit a large anomalous Hall effect. A hysteresis in the anomalous Hall effect appears below 2.5 K in the most heavily doped sample, which indicates the occurrence of a ferromagnetic phase. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

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Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)