A novel model for smectic liquid crystals: Elastic anisotropy and response to a steady-state flow

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in J. Chem. Phys. 145, 164903 (2016) and may be found at https://doi.org/10.1063/1.4965711.By means of a combination of equilibrium Monte Carlo and molecular dynamics simulations and nonequilibrium molecular dynamics we investigate the ordered, uniaxial phases (i.e., nematic and smectic A) of a model liquid crystal. We characterize equilibrium behavior through their diffusive behavior and elastic properties. As one approaches the equilibrium isotropic-nematic phase transition, diffusion becomes anisotropic in that self-diffusion D⊥ in the direction orthogonal to a molecule’s long axis is more hindered than self-diffusion D∥ in the direction parallel to that axis. Close to nematic-smectic A phase transition the opposite is true, D∥ < D⊥. The Frank elastic constants K1, K2, and K3 for the respective splay, twist, and bend deformations of the director field n̂ are no longer equal and exhibit a temperature dependence observed experimentally for cyanobiphenyls. Under nonequilibrium conditions, a pressure gradient applied to the smectic A phase generates Poiseuille-like or plug flow depending on whether the convective velocity is parallel or orthogonal to the plane of smectic layers. We find that in Poiseuille-like flow the viscosity of the smectic A phase is higher than in plug flow. This can be rationalized via the velocity-field component in the direction of the flow. In a sufficiently strong flow these smectic layers are not destroyed but significantly bent.DFG, 65143814, GRK 1524: Self-Assembled Soft-Matter Nanostructures at Interface

Structure and evolution of Subtropical Cyclone Anita as evaluated by heat and vorticity budgets

This paper explores the evolution of subtropical cyclone Anita, which occurred near the east coast of Brazil (~19.S-37.W) in March 2010. Thermodynamic and dynamic processes during Anita's lifecycle are investigated using the heat and vorticity budget equations. The cyclone developed with hybrid characteristics and moved anomalously to the southwest where it coupled with an upper level cut-off low during the mature phase. This coupling was the main dynamical mechanism for further cyclone deepening. Anita then remained quasi-stationary about 30.S -47.W for two days due to an upper level dipole pattern which prevented earlier displacement of the upper level low counterpart. When the dipole pattern dissipated, the cyclone moved southeast and underwent extratropical transition whilst merging with a mid-latitude frontal cyclone. Diabatic heating and horizontal temperature advection are found to be essential for the subtropical development. During extratropical transition, it is instead diabatic cooling together with adiabatic cooling and warm air advection that act as the main mechanisms to influence the local temperature tendencies at low levels. Low level cyclonic tendencies were mostly due to convergent flow, and the residual vorticity partially destroyed the vorticity tendencies produced by the divergence term. Moreover, in regions and levels where convection could explain some of the vorticity tendencies, it is found that apparent sinks of cyclonic vorticity were related to negative vorticity due to divergence (i.e., convergent flow), whilst apparent sources were related to positive vorticity due to divergence (i.e., divergent flow)

Program FFlexCom — High frequency flexible bendable electronics for wireless communication systems

Today, electronics are implemented on rigid substrates. However, many objects in daily-life are not rigid — they are bendable, stretchable and even foldable. Examples are paper, tapes, our body, our skin and textiles. Until today there is a big gap between electronics and bendable daily-life items. Concerning this matter, the DFG Priority Program FFlexCom aims at paving the way for a novel research area: Wireless communication systems fully integrated on an ultra-thin, bendable and flexible piece of plastic or paper. The Program encompasses 13 projects led by 25 professors. By flexibility we refer to mechanical flexibility, which can come in flavors of bendability, foldability and, stretchability. In the last years the speed of flexible devices has massively been improved. However, to enable functional flexible systems and operation frequencies up to the sub-GHz range, the speed of flexible devices must still be increased by several orders of magnitude requiring novel system and circuit architectures, component concepts, technologies and materials

TURBOMOLE: Today and Tomorrow

TURBOMOLE is a highly optimized software suite for large-scale quantum-chemical and materials science simulations of molecules, clusters, extended systems, and periodic solids. TURBOMOLE uses Gaussian basis sets and has been designed with robust and fast quantum-chemical applications in mind, ranging from homogeneous and heterogeneous catalysis to inorganic and organic chemistry and various types of spectroscopy, light–matter interactions, and biochemistry. This Perspective briefly surveys TURBOMOLE’s functionality and highlights recent developments that have taken place between 2020 and 2023, comprising new electronic structure methods for molecules and solids, previously unavailable molecular properties, embedding, and molecular dynamics approaches. Select features under development are reviewed to illustrate the continuous growth of the program suite, including nuclear electronic orbital methods, Hartree–Fock-based adiabatic connection models, simplified time-dependent density functional theory, relativistic effects and magnetic properties, and multiscale modeling of optical properties

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

Background: The EMPA KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population. Methods: EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110. Findings: Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5–2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62–0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16–1·59), representing a 50% (42–58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all &gt;0·1). Interpretation: In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease. Funding: Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council

Martin Grotjahn Collection 1966-1967

Two articles about Sigmund Freud and 2 book reviews pertaining to psychoanalysis.digitizedGerald Oliven, 1968Martin Grotjahn studied medicine in Berlin and practiced psychotherapy in Germany and in the United States

Model-based feedforward control in industrial robotics

Simple linear joint controllers are still used in typical industrial robotic systems. The use of these controllers leads to non-negligible dynamic path deviations for applications that require high path accuracy. These deviations result from the strong influence of non-linearities, such as multi-body dynamics and gear friction. Sophisticated nonlinear control algorithms, known from the literature, are still not used because they usually require an expensive change of the control architecture. Therefore, different compensation methods are compared in this paper which reduce the path deviations by correction of the desired trajectory'. This means that no torque interface is required, only an interface for path corrections is necessary. Such an interface normnally exists so that the methods can simply be implemented within standard industrial controls. Using the industrial robot Siemens manutec-r15 the methods are experimentally compared with respect to their efficiency and practical applicability. Starting from this, one method is chosen for application to the state-of-the-art industrial robot KUKA KR15. The algorithm is based on a complete nonlinear dynamic model of the robot. It is integrated into the standard control KRC1. The experimental results prove the efficiency and the industrial applicability of the method