Optical anisotropy of the kagome magnet FeSn: dominant role of excitations between kagome and Sn layers

Antiferromagnetic FeSn is considered to be a close realization of the ideal two-dimensional (2D) kagome lattice, hosting Dirac cones, van Hove singularities, and flat bands, as it comprises Fe3Sn kagome layers well separated by Sn buffer layers. We observe a pronounced optical anisotropy, with the low-energy optical conductivity being surprisingly higher perpendicular to the kagome planes than along the layers. This finding contradicts the prevalent picture of dominantly 2D electronic structure for FeSn. Our material-specific theory reproduces the measured conductivity spectra remarkably well. A site-specific decomposition of the optical response to individual excitation channels shows that the optical conductivity for polarizations both parallel and perpendicular to the kagome plane is dominated by interlayer transitions between kagome layers and adjacent Sn-based layers. Moreover, the matrix elements corresponding to these transitions are highly anisotropic, leading to larger out-of-plane conductivity. Our results evidence the crucial role of interstitial layers in charge dynamics even in seemingly 2D systems

Comparison of three formulas to evaluate acute renal failure in preeclamptic puerperal women

Evaluamos fórmulas para calcular la tasa de filtración glomerular en casos de pacientes obstétricas atendidas en la unidad de cuidados intensivos.Introduction: Acute renal failure in puerperal women who have suffered preeclampsia and HELLP syndrome has been scarcely studied. Aim: to compare the Cockroft-Gault, Modification of Diet in Renal Disease, and Chronic Kidney Disease Epidemiology Collaboration equations with the 24 hour creatinine clearance formula in puerperal women. Materials & Methods: This was an observational study. The selected formulas were calculated at 1, 8, 16 and 24 hours after delivery. Pearson correlation and Bland-Altman tests were performed. Results: 38 patients (mean age 26.4 years) were included. The three highest correlation coefficients with the 24 h creatinine clearance were the Modification of Diet in Renal Disease at 8 hours (r² = 0.920), and the Chronic Kidney Disease Epidemiology Collaboration equation at 24 (r² = 0.847) and 16 hours (r² = 0.842) post-delivery. Conclusion: In puerperal women who have suffered preeclampsia and HELLP syndrome, the Chronic Kidney Disease Epidemiology Collaboration equation shows more consistent results the first 24 hours post-delivery

Windenergieanlage GROWIAN II Schlussbericht

With 23 refs., 11 tabs., 69 figs.Copy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Key informant models for measuring group-level variables in small groups: application to plural subject theory

We offer a new conceptualization and measurement models for constructs at the group-level of analysis in small group research. The conceptualization starts with classical notions of group behavior proposed by Tönnies, Simmel, and Weber and then draws upon plural subject theory by philosophers Gilbert and Tuomela to frame a new perspective applicable to many forms of small group behavior. In the proposed measurement model, a collective property is operationalized as shared interpersonal action that explicitly allows us to control for systematic (method) error and random error. Group members act as key-informants of group properties and processes and are treated as methods in a multi-trait multi-method setting to validate our models. The models are applied to empirical data of 277 three-person groups to develop and illustrate new procedures for ascertaining variation in measures due to hypothesized construct(s), method error, and random error. Implications and guidelines for small group research are discussed