Experiments on identification and control of inflow disturbances in contracting streams

Vorticity from all surfaces and isolated objects in the vicinity of the fan intake, including the outside surfaces of the fan housing, were identified as the major sources for disturbances leading to blade passing frequency noise. The previously proposed mechanism based on atmospheric turbulence is refuted. Flow visualization and hot wire techniques were used in three different facilities to document the evolution of various types of disturbances, including the details of the mean flow and turbulence characteristics. The results suggest that special attention must be devoted to the design of the inlet and that geometric modeling may not lead to adequate simulation of the in flight characteristics. While honeycomb type flow manipulators appear to be effective in reducing some of the disturbances, higher pressure drop devices that generate adequate turbulence, for mixing of isolated nonuniformities, may be necessary to suppress the remaining disturbances. The results are also applicable to the design of inlets of open return wind tunnels and similar flow facilities

Asymptotic description of solutions of the exterior Navier Stokes problem in a half space

We consider the problem of a body moving within an incompressible fluid at constant speed parallel to a wall, in an otherwise unbounded domain. This situation is modeled by the incompressible Navier-Stokes equations in an exterior domain in a half space, with appropriate boundary conditions on the wall, the body, and at infinity. We focus on the case where the size of the body is small. We prove in a very general setup that the solution of this problem is unique and we compute a sharp decay rate of the solution far from the moving body and the wall

Effect of substrate thermal resistance on space-domain microchannel

In recent years, Fluorescent Melting Curve Analysis (FMCA) has become an almost ubiquitous feature of commercial quantitative PCR (qPCR) thermal cyclers. Here a micro-fluidic device is presented capable of performing FMCA within a microchannel. The device consists of modular thermally conductive blocks which can sandwich a microfluidic substrate. Opposing ends of the blocks are held at differing temperatures and a linear thermal gradient is generated along the microfluidic channel. Fluorescent measurements taken from a sample as it passes along the micro-fluidic channel permits fluorescent melting curves to be generated. In this study we measure DNA melting temperature from two plasmid fragments. The effects of flow velocity and ramp-rate are investigated, and measured melting curves are compared to those acquired from a commercially available PCR thermocycler

Investigations on the slope efficiency of a pulsed 2.8-µm Er3+:LiYF4 laser

A slope efficiency of 40% from an Er3+:LiYF4 laser is demonstrated under pulsed Ti:sapphire pumping at 973 nm. With reduction of the pump-pulse duration a significant decrease of the slope efficiency and an increase of the threshold is observed in the experiment and confirmed with high accuracy in a computer simulation. This behavior is due to interionic upconversion from the lower laser level, which leads to energy recycling into the upper laser level. The upconversion rate is negative at threshold but increases strongly with rising pump pulse energy, thus enhancing the slope efficiency. The conditions are derived that are necessary for achieving the high slope efficiency of the energy-recycling regime

Hemoglobinuria posparto en vacas de tres rebaños lecheros de la región del Bío-Bío, Chile

RESUMEN La hemoglobinuria posparto es una enfermedad metabólica esporádica que presentanlas vacas lecheras, manifestándose dentro de las 6 semanas posparto asociada al rápidoincremento de la producción de leche al inicio de la lactancia. Se caracteriza por una anemiaaguda regenerativa por hemólisis intravascular con hemoglobinuria. Entre los factores quepredisponen a su presentación están la ingesta de una dieta carente en fósforo, cobre oselenio, o bien concomitante a la presencia de agentes hemolíticos en plantas crucíferascomo el nabo o colza. El trabajo describe aspectos relacionados a la presentación de brotesde la enfermedad en tres rebaños lecheros de la región del Bío-bío, Chile, con hipofosfatemiaasociada a la incorporación de derivados de la remolacha azucarera en la dieta

Anoxygenic photosynthesis and dark carbon metabolism under micro-oxic conditions in the purple sulfur bacterium "Thiodictyon syntrophicum" nov. strain Cad16T

The microbial ecosystem of the meromictic Lake Cadagno (Ticino, Swiss Alps) has been studied intensively to understand metabolic functions driven by the highly abundant anoxygenic phototrophic sulfur bacteria of the families Chromatiaceae and Chlorobiaceae. It was found that the sequenced isolate "Thiodictyon syntrophicum" nov. sp. str. Cad16T, belonging to the Chromatiaceae, may fix 26% of all bulk inorganic carbon in the chemocline at day and night. With this study, we elucidated the mode of dark carbon fixation of str. Cad16T with a combination of long-term monitoring of key physicochemical parameters with CTD, 14C-incorporation experiments and quantitative proteomics of in situ dialysis bag incubations of pure cultures. Regular vertical CTD profiling during the study period in summer 2017 revealed that the chemocline sank from 12 to 14 m which was accompanied by a bloom of cyanobacteria and the subsequent oxygenation of the deeper water column. Sampling was performed both day and night in September. While CO2 assimilation rates were higher during the light period, the relative change in the proteome (663 quantified proteins) was only 1% of all CDS encoded in str. Cad16T. Oxidative respiration was thereby upregulated at light, whereas stress-related mechanisms prevailed during the night. These results indicate that the low light availability due to high cell concentrations and the oxygenation of the chemocline induced a mixotrophic growth in str. Cad16T. The complete proteome data have been deposited to the ProteomeXchange with identifier PXD010641

Ability of 3 Frailty Measures to Predict Short-Term Outcomes in Older Patients Admitted for Post-Acute Inpatient Rehabilitation.

OBJECTIVES To evaluate the ability of 3 commonly used frailty measures to predict short-term clinical outcomes in older patients admitted for post-acute inpatient rehabilitation. DESIGN Observational cohort study. SETTING AND PARTICIPANTS Consecutive patients (n = 207) admitted to a geriatric inpatient rehabilitation facility. METHODS Frailty on admission was assessed using a frailty index, the physical frailty phenotype, and the Clinical Frailty Scale (CFS). Predictive capacity of the frailty instruments was analyzed for (1) nonhome discharge, (2) readmission to acute care, (3) functional decline, and (4) prolonged length of stay, using multivariate logistic regression models and receiver operating characteristic (ROC) curves. RESULTS The number of patients classified as frail was 91 (44.0%) with the frailty index, 134 (64.7%) using the frailty phenotype, and 151 (73.0%) with the CFS. The 3 frailty measures revealed acceptable discriminatory accuracy for nonhome discharge (area under the curve ≥ 0.7) but differed in their predictive ability: the adjusted odds ratio (OR) for nonhome discharge was highest for the CFS [6.2, 95% confidence interval (CI) 1.8-21.1], compared to the frailty index (4.1, 95% CI 2.0-8.4) and the frailty phenotype (OR 2.9, 95% CI 1.2-6.6). For the other outcomes, discriminatory accuracy based on ROC tended to be lower and predictive ability varied according to frailty measure. Readmission to acute care from inpatient rehabilitation was predicted by all instruments, most pronounced by the frailty phenotype (OR 5.4, 95% CI 1.6-18.8) and the frailty index (OR 2.5, 95% CI 1.1-5.6), and less so by the CFS (OR 1.4, 95% CI 0.5-3.8). CONCLUSIONS AND IMPLICATIONS Frailty measures may contribute to improved prediction of outcomes in geriatric inpatient rehabilitation. The choice of the instrument may depend on the individual outcome of interest and the corresponding discriminatory ability of the frailty measure