bluuebunny/crossref_metadata_2025 huggingface dataset:
Cognitive resources are distributed among the entire auditory landscape in auditory scene analysis
Authors: Symonds Renee M. , Zhou Juin W. , Cole Sally L. , Brace Kelin M. , Sussman Elyse S.
Published: October 2019

Although attention has been shown to enhance neural representations of selected inputs, the fate of unselected background sounds is still debated. The goal of the current study was to understand how processing resources are distributed among attended and unattended sounds during auditory scene analysis. We used a three‐stream paradigm with four acoustic features uniquely defining each sound stream (frequency, envelope shape, spatial location, tone quality). We manipulated task load by having participants perform a difficult auditory task and an easy movie‐viewing task with the same set of sounds in separate conditions. The mismatch negativity (MMN) component of event‐related brain potentials (ERPs) was measured to evaluate sound processing in both conditions. We found no effect of task demands on unattended sound processing: MMNs were elicited by unattended deviants during both low‐ and high‐load task conditions. A key factor of this result was the use of unique tone feature combinations to distinguish each of the three sound streams, strengthening the segregation of streams. In the auditory task, the P3b component demonstrates a two‐stage process of target evaluation. Thus, these results, in conjunction with results of previous studies, suggest that stimulus‐driven factors that strengthen stream segregation can free up processing capacity for higher‐level analyses. The results illustrate the interactive nature of top‐down and stimulus‐driven processes in stream formation, supporting a distributive theory of attention that balances the strength of the bottom‐up input with perceptual goals in analyzing the auditory scene.
Microalgal pigment induction and transfer in aquaculture
Authors: Pérez‐Legaspi Ignacio Alejandro , Valadez‐Rocha Veronica , Ortega‐Clemente Luis Alfredo , Jiménez‐García Maria Isabel
Published: October 2019

Pigments are bioactive compounds produced by microalgae which have a very important role in the health and performance of aquaculture species, particularly in the early larval stages of marine fish and crustaceans. We review the production of specific pigments by microalgal species emphasizing on the specific culture and stress conditions to promote the accumulation of large amounts of pigments in microalgae such as Haematococcus pluvialis, and different genus of Dunaliella, Muriellopsis, Scenedesmus, Chlorella and Chlorococcum used for aquaculture. We also discuss the differences among different large‐scale production systems and review the dose–effect relation of pigments on the health and performance of different aquaculture species as well as discuss the feasibility of transferring the pigments by using zooplankton species to obtain the benefits of pigments and other compounds produced by microalgae. We conclude more research is needed on the specific dose effects of pigments in the health and performance of aquaculture species at specific developmental stages and that the transfer of these bioactive compounds using zooplankton species is worthy of consideration by the aquaculture industry.
Projected climate change effects on Alberta's boreal forests imply future challenges for oil sands reclamation
Authors: Nenzén Hedvig K. , Price David T. , Boulanger Yan , Taylor Anthony R. , Cyr Dominic , Campbell Elizabeth
Published: October 2019

Climate change will drive significant changes in vegetation cover and also impact efforts to restore ecosystems that have been disturbed by human activities. Bitumen mining in the Alberta oil sands region of western Canada requires reclamation to “equivalent land capability,” implying establishment of vegetation similar to undisturbed boreal ecosystems. However, there is consensus that this region will be exposed to relatively severe climate warming, causing increased occurrence of drought and wildfire, which threaten the persistence of both natural and reclaimed ecosystems. We used a landscape model, LANDIS‐II, to simulate plant responses to climate change and disturbances, forecasting changes to boreal forests within the oil sands region. Under the most severe climate forcing scenarios (representative concentration pathway [RCP] 8.5) the model projected substantial decreases in forest biomass, with the future forest being dominated by drought‐ and fire‐tolerant species characteristic of parkland or prairie ecosystems. In contrast, less extreme climate forcing scenarios (RCPs 2.6 and 4.5) had relatively minor effects on forest composition and biomass with boreal conifers continuing to dominate the landscape. If the climate continues to change along a trajectory similar to those simulated by climate models for the RCP 8.5 forcing scenario, current reclamation goals to reestablish spruce‐dominated boreal forest will likely be difficult to achieve. Results from scenario modeling studies such as ours, and continued monitoring of change in the boreal forest, will help inform reclamation practices, which could include establishment of species better adapted to warmer and drier conditions.
Clastic injectites, internal structures and flow regime during injection: The Sea Lion Injectite System, North Falkland Basin
Authors: Dodd Thomas J. H. , McCarthy Dave J. , Clarke Stuart M.
Published: October 2019

This paper details and describes a suite of 143 sub‐seismic‐scale clastic injectites encountered within the early Cretaceous, early post‐rift of the deep‐lacustrine North Falkland Basin. The injectites, referred to here as the Sea Lion Injectite System, are encountered below, above and in between the hydrocarbon‐bearing, deep‐lacustrine turbidite sandstones of the Bleaker 30, Sea Lion North, Sea Lion, Casper and Beverley fans. Sedimentary structures are documented within the injectites including: planar laminations, mud‐clast imbrication and clast alignment. Clasts align along centimetre‐scale foresets formed through ripple‐scale bedform migration in a hydraulically‐open fracture. The style of flow within the injectite system is interpreted as initially through fluid turbulence during an open fracture phase, which was followed by a later stage where laminar flow dominated, most likely during the closing phase of the fracture system. The host rocks display evidence for ductile deformation, which along with ptygmatic folding of dykes and internally injected mud‐clasts, suggests a period of injection into relatively uncompacted sediments. Evidence for brittle fracturing, in the form of stepped margins may be indicative of a separate phase of emplacement into more‐compacted sediments. This variability in deformation styles is related to multi‐phased injection episodes into host strata at different stages of consolidation and lithification at shallow burial depths. Injectites have been identified in four stratigraphic groupings: above the Bleaker 30 Fan and within/above the Sea Lion North Fan; within the hydrocarbon‐bearing Sea Lion Fan; overlying the Sea Lion Fan; and above/below the hydrocarbon‐bearing Casper and Beverley fans. This spatial association with the hydrocarbon‐bearing fans of the North Falkland Basin is important, considering the ability of injectite networks to form effective fluid‐flow conduits in the subsurface. Consequently, the findings of this study will improve the characterization of sub‐seismic scale injectites (and therefore fluid conduits) within otherwise impermeable strata.
Retinal endothelial function in cardiovascular risk patients: A randomized controlled exercise trial
Authors: Streese Lukas , Kotliar Konstantin , Deiseroth Arne , Infanger Denis , Gugleta Konstantin , Schmaderer Christoph , Hanssen Henner
Published: October 2019

The aim of this study was to investigate, for the first time, the effects of high‐intensity interval training (HIIT) on retinal microvascular endothelial function in cardiovascular (CV) risk patients. In the randomized controlled trial, middle‐aged and previously sedentary patients with increased CV risk (aged 58 ± 6 years) with ≥ two CV risk factors were randomized into a 12‐week HIIT (n = 33) or control group (CG, n = 36) with standard physical activity recommendations. A blinded examiner measured retinal endothelial function by flicker light‐induced maximal arteriolar (ADmax) and venular (VDmax) dilatation as well as the area under the arteriolar (AFarea) and venular (VFarea) flicker curve using a retinal vessel analyzer. Standardized assessments of CV risk factors, cardiorespiratory fitness, and retinal endothelial function were performed before and after HIIT. HIIT reduced body mass index, fat mass, and low‐density lipoprotein and increased muscle mass and peak oxygen uptake (VO2peak). Both ADmax (pre: 2.7 ± 2.1%, post: 3.0 ± 2.2%, P = .018) and AFarea (pre: 32.6 ± 28.4%*s, post: 37.7 ± 30.6%*s, P = .016) increased after HIIT compared with CG (ADmax, pre: 3.2 ± 1.8%, post: 2.9 ± 1.8%, P = .254; AFarea, pre: 41.6 ± 28.5%*s, post: 37.8 ± 27.0%*s, P = .186). Venular function remained unchanged after HIIT. There was a significant association between ∆‐change VO2peak and ∆‐changes ADmax and AFarea (P = .026, R2 = 0.073; P = .019, R2 = 0.081, respectively). 12‐weeks of HIIT improved retinal endothelial function in middle‐aged patients with increased CV risk independent of the reduction in classical CV risk factors. Exercise has the potential to reverse or at least postpone progression of small vessel disease in older adults with increased CV risk under standard medication. Dynamic retinal vessel analysis seems to be a sensitive tool to detect treatment effects of exercise interventions on retinal microvascular endothelial function in middle‐aged individuals with increased CV risk.
What makes children defy their peers? Chinese and Spanish preschoolers' decisions to trust (or not) peer consensus
Authors: Sebastián‐Enesco Carla , Guerrero Silvia , Enesco Ileana
Published: October 2019

The more people agree on the same piece of information, the more likely are individuals to endorse the testimonial information. Children are sensitive to consensus but their trust in what a majority says also depends on the decision context, their previous knowledge, and, interestingly, the culture in which they develop. Here we study Chinese (N = 60) and Spanish (N = 48) preschoolers' sensitivity to the opinion of a group of peers in consensus regarding (a) peer interaction events and (b) use of artifacts. For each context, we varied the degree of ambiguity of the situations: unfamiliar, ambiguous, and familiar, where the majority offered a transgressive opinion in conflict with “common sense.” Children were more likely to trust their peers in the unfamiliar and ambiguous situations. In the familiar situations, children showed greater acceptance of transgressive claims regarding artifacts than peer interaction events. The two cultural groups, however, significantly differed in the degree of endorsement. Although Chinese children gave little credibility to their peers even when facing novel information, Spaniards deferred to them, even at the expense of their own criteria. Together with previous findings, these results indicate culture‐specific patterns related to children's attitudes toward peers versus adults as sources of knowledge.
Haemodynamic and cerebrovascular effects of intermittent lower‐leg compression as countermeasure to orthostatic stress
Authors: Gibbons Travis D. , Zuj Kathryn A. , Prince Chekema N. , Kingston David C. , Peterson Sean D. , Hughson Richard L.
Published: October 2019

New Findings

What is the central question of this study?

Does smartly timed intermittent compression of the lower legs alter cerebral blood velocity and oxygenation during acute orthostatic challenges?

What is the main finding and its importance?

Intermittent compression timed to the local diastolic phase increased the blood flux through the legs and heart after two different orthostatic stress tests. Cerebral blood velocity improved during the first minute of recovery, and indices of cerebral tissue oxygenation remained elevated for 2 min. These results provide promise for the use of lower‐leg active compression as a therapeutic tool for individuals vulnerable to initial orthostatic hypotension and orthostatic stress.

Intermittent compression of the lower legs provides the possibility of improving orthostatic tolerance by actively promoting venous return and improving central haemodynamics. We tested the hypothesis that intermittent compression of 65 mmHg timed to occur only within the local diastolic phase of each cardiac cycle would attenuate the decrease in blood pressure and improve cerebral haemodynamics during the first minute of recovery from two different orthostatic stress tests. Fourteen subjects (seven female) performed four squat‐to‐stand transitions and four repeats of standing bilateral thigh‐cuff occlusion and release (TCR), with intermittent compression of the lower legs applied in half of the trials. Blood flow in the superficial femoral artery, mean arterial pressure, Doppler ultrasound cardiac output, total peripheral resistance, middle cerebral artery blood velocity (MCAv) and cerebral tissue saturation index (TSI%) were monitored. With both orthostatic stress tests, there was a significant compression × time interaction for superficial femoral artery flow (P < 0.001). The hypotensive state was attenuated with intermittent compression despite decreased total peripheral resistance (squat‐to‐stand, compression × time interaction, P < 0.001; TCR, compression × time interaction, P = 0.002) as a consequence of elevated cardiac output in both tests (P < 0.001). Intermittent compression also increased MCAv (P = 0.001) and TSI% (P < 0.001) during the squat‐to‐stand transition and during TCR (MCAv and TSI%, compression × time interaction, P < 0.001). Intermittent compression of the lower legs during quiet standing after an active orthostatic challenge augmented local, central and cerebral haemodynamics, providing potential as a therapeutic tool for individuals vulnerable to orthostatic stress.
Estudio de la rentabilidad de una renta de jubilación contratada a prima pura (única y periódica)
Authors: Pérez Fructuoso María José , Alegre Escolano Antonio
Published: October 2019

Este trabajo analiza la rentabilidad que puede obtener un asegurado por contratar una renta diferida temporal o vitalicia. Al estar esta operación actuarial condicionada a la probabilidad de supervivencia del asegurado, la rentabilidad de esta es aleatoria y depende de la distribución de probabilidad asociada a dicha supervivencia. Definiremos la rentabilidad esperada y a partir de la distribución de probabilidad de la variable aleatoria que denominamos beneficio del asegurado, obtendremos unos parámetros de decisión que reflejen el riesgo de la operación y su influencia en dicha rentabilidad esperada. El desarrollo teórico se realizará para primas únicas y periódicas, en ambos casos, bajo la hipótesis de prima pura. Finalmente, plantearemos un análisis empírico que muestre la aplicabilidad de los resultados obtenidos, con el objetivo de que el asegurado tome sus decisiones en ambiente aleatorio con la máxima información.
Obligaciones generales de información en la nueva regulación española de distribución de seguros
Authors: Peñas Moyano María Jesús
Published: October 2019

La transposición de la Directiva (UE) 2016/97 del Parlamento Europeo y del Consejo, de 20 de enero de 2016 (IDMII) al Derecho español precisa de la elaboración de una norma nueva que recoja las novedades de esta directiva. Entre ellas destacan las nuevas obligaciones generales de información que se imponen a los distribuidores de seguros, considerando la amplitud subjetiva con la que ha de manejarse este grupo de actores en el mercado. Especial relevancia alcanza la información relativa a la remuneración a percibir, así como evitar los posibles conflictos de interés que puedan surgir. Igualmente, hay que hacer mención en el ámbito de los seguros distintos de vida a la implantación del documento de información previa, conocido por sus siglas como IPID.
La regulación de los intermediarios de seguros en Colombia: un régimen de supervisión asimétrico
Authors: Vergara Arregocés Carlos Daniel
Published: October 2019

En Colombia existen los denominados intermediarios tradicionales de seguros, a saber, las agencias de seguros, los agentes de seguros y las sociedades corredoras de seguros, todos regidos por particularidades normativas que los distinguen entre ellos. El presente trabajo hace un estudio de la regulación de estas figuras en nuestro país, incluyendo las interpretaciones que el supervisor (Superintendencia Financiera) y la jurisprudencia hacen de ella, haciendo cuestionamientos críticos que exhiben los efectos prácticos de esta normatividad en el mercado asegurador.
La conciencia desgraciada hacia el reencuentro del amor: Hegel y Rosenzweig
Authors: Catz Shirly Mariel
Published: October 2019

La Estrella de la Redención se postula como una crítica a Hegel y su lógica de la Aufhebung, pero en esta obra Rosenzweig no niega la verdad del sistema hegeliano, sino su absolutización. Desde ese punto de vista, Rosenzweig retoma “otro” Hegel: el de sus Escritos de juventud, atendiendo a su concepción del amor, y el de la Fenomenología del espíritu, en una búsqueda de sistema ligada a la experiencia. Desde un Hegel particular, aunque más allá de él, Rosenzweig construye una filosofía relacional, donde los elementos no se superan sino que conviven entre sí. Analizaremos la fractura de la Totalidad en la triada Dios-Hombre-Mundo, para estudiar luego su relación efectiva a través del amor, y el vínculo necesario entre judaísmo y cristianismo como modo de anticipar la Redención; vínculo desde el cual Rosenzweig sostiene, en contra en este punto de Hegel, que ambas religiones comparten un contenido común, en una relación simbolizada en la letra “y”.
Significance of Prandtl Number on the Heat Transport and Flow Structure in Rotating Rayleigh–Bénard Convection
Authors: Venugopal T Vishnu , De Arnab Kumar , Mishra Pankaj Kumar
Published: October 2019

A direct numerical simulation of rotating Rayleigh–Bénard convection (RBC) for different fluids (Pr=0.015,0.7,1,7,20, and 100) in a cylindrical cell of aspect ratio Γ=0.5 is carried out in this work. The effect of rotation on the heat transfer rate, flow structures, their associated dynamics, and influence on the boundary layers are investigated. The Rayleigh number is fixed to Ra=106 and the rotation rates are varied for a wide range, starting from no rotation (Ro→∞) to high rotation rates (Ro≈0.01). For all the Prandtl numbers (Pr=0.015–100), a reduction in heat transfer with increase in rotation is observed. However, for Pr=7 and 20, a marginal increase of the Nusselt number for low rotation rates is obtained, which is attributed to the change in the flow structure from quadrupolar to dipolar state. The change in flow structure is associated with the statistical behavior of the boundary layers. As the flow makes a transition from quadrupolar to dipolar state, a reduction in the thermal boundary layer thickness is observed. At higher rotation rates, the thermal boundary layer thickness shows a power law variation with the rotation rate. The power law exponent is close to unity for moderate Pr, while it reduces for both lower and higher Pr. At extremely high rotation rates, the flow makes a transition to the conduction state. The critical rotation rate (1/Roc) for which transition to the conduction state is observed depends on the Prandtl number according to 1/Roc∝Pr0.5.
Experimental Study of Flow Inside a Centrifugal Fan Using Magnetic Resonance Velocimetry
Authors: Hoffman Davis W. , Villafañe Laura , Elkins Christopher J. , Eaton John K.
Published: October 2019

Three-dimensional (3D), three-component time-averaged velocity fields have been measured within a low-speed centrifugal fan with forward curved (FC) blades. The model investigated is representative of fans commonly used in automotive applications. The flow was analyzed at two Reynolds numbers for the same ratio of blade rotational speed to outlet flow velocity. The flow patterns inside the volute were found to have weak sensitivity to Reynolds number. A pair of counter-rotating vortices evolves circumferentially within the volute with positive and negative helicity in the upper and lower regions, respectively. Measurements have been further extended to capture phase-resolved flow features by synchronizing the data acquisition with the blade passing frequency. The mean flow field through each blade passage is presented including the jet-wake structure extending from the blade and the separation zone on the suction side of the blade leading edge.
Design of Full-Scale Endwall Film Cooling of a Turbine Vane
Authors: Liu Jian , Du Wei , Zhang Guohua , Hussain Safeer , Wang Lei , Xie Gongnan , Sundén Bengt
Published: October 2019

Endwall film cooling is a significant cooling method to protect the endwall region and the junction region of endwall and a turbine vane, where usually a relatively high temperature load exists. This work aims to find the optimized arrangement of film cooling holes on the endwall and improve the film cooling in some difficult regions on the endwall, such as pressure side-endwall junction region. Several ideas for film cooling hole arrangement design are proposed, based on the pressure coefficient distribution, the streamline distribution, and the heat transfer coefficient (HTC) distribution, respectively. Four specified designs are built and compared. The results are obtained by numerical calculations with a well-validated turbulence model, the k–ω shear stress transport (SST) model. From this work, the designs based on the pressure coefficient distribution (designs 1 and 2) force the flow from the pressure side to the suction side (SS), especially in design 2, which adopts compound angle holes. The designs based on pressure coefficients have benefit in the cooling of the SS but give worse coolant coverage on the pressure side. In addition, designs 1 and 2 have little influence on the original pressure field. The design based on the streamline distributions (design 3) has larger coolant coverage on the endwall and provides good coolant coverage on the endwall and pressure side junction region. The design based on the HTC distribution provides large overall film cooling effectiveness on both the pressure side and the SS. More film cooling holes are placed on the high temperature regions, which is more effective in practice.
Heat Transfer Enhancement for Wake Zone Using Slit Pillar in Microchannel Heat Sinks
Authors: Cheng Xiao , Wu Huiying
Published: October 2019

Pillar microchannel heat sinks have been widely used for chip cooling, while their overall heat transfer performance is restricted by the stagnation flow in pillar wake zone. In this work, a simple but effective method using slit microstructure modified on pillar was proposed to enhance wake zone heat transfer. It enables a special flow path for the incoming fluid that intensively disturbs the wake fluid. To validate the proposed method, a three-dimensional simulation was employed to study the laminar flow and heat transfer characteristics in the slit pillar microchannel. The pillar without slit design was also investigated for comparative analysis. Effects of slit angle (θ), height over diameter ratio (H/D), and blocking ratio (D/W) of a single pillar were systematically studied at the Reynolds numbers of 26–260. Results showed the case with θ = 0 deg always demonstrated lower surface temperature, higher Nusselt number and higher thermal performance index (TPI) compared to other cases with different slit angles at the same conditions. Furthermore, it was interesting to find that the slit configuration was not suitable for long pillar microchannel, but preferred for high blocking ratio pillar microchannel at present ranges (H/D ≤ 1, D/W ≤ 0.5). The slit pillar array microchannel was also explored and observed with improved overall heat transfer performance. The proposed slit microstructure well prevents the heat transfer deterioration in pillar wake zone, which is promisingly to be used for cooling performance improvement of electronic device.
Experimental Validation of ANSYS CFX for Transient Flows With Heat Transfer in a Tubular Heat Exchanger
Authors: Papukchiev Angel
Published: October 2019

Within the European SESAME project, extensive experimental work was performed and complemented by the development, application, and validation activities of thermal-hydraulic simulation tools for different scales. The TALL-3D experimental facility, operated by KTH Royal Institute of Technology in Stockholm, is designed for thermal-hydraulic experiments with lead-bismuth eutectic (LBE) coolant at natural and forced circulation conditions. The heat generated in the primary TALL-3D circuit is transferred via a double-tube counter-flow heat exchanger (HX) to the secondary side, which is cooled by glycerol oil. Validation calculations with the coupled simulation code ATHLET-ANSYS CFX within the European THINS project showed that one of the major challenges for this one-dimensional–three-dimensional (1D–3D) simulation of the experimental facility lies in the calculation of the HX with ATHLET. This is due to the fact that glycerol oil properties are not yet available for ATHLET. In order to better understand the flow and heat transfer phenomena inside the HX, 3D stand-alone calculations with ANSYS CFX were carried out for the SESAME experiment TG03.S301.03. The data generated in this experimental run is challenging for validation of computational fluid dynamics (CFD) codes, because the test combines heat transfer between buoyancy-driven LBE flow in the primary circuit and a turbulent oil flow in the secondary TALL-3D side. Moreover, the validation gets even more difficult for the CFD approach due to the fact that both coolants are nonunity Prandtl fluids, and this requires a careful modeling of the turbulent heat flux. In this paper, the TALL-3D HX behavior during test TG03.S301.03 is analyzed, and the results of the ANSYS CFX calculations are compared with measurements.
Modeling Geared Turbofan and Open Rotor Engine Performance for Year-2050 Long-Range and Short-Range Aircraft
Authors: Mastropierro Francesco S. , Sebastiampillai Joshua , Jacob Florian , Rolt Andrew
Published: October 2019

This paper provides design and performance data for two envisaged year-2050 engines: a geared high bypass turbofan for intercontinental missions and a contra-rotating pusher open rotor targeting short to medium range aircraft. It defines component performance and cycle parameters, general arrangements, sizes, and weights. Reduced thrust requirements reflect expected improvements in engine and airframe technologies. Advanced simulation platforms have been developed to model the engines and details of individual components. The engines are optimized and compared with “baseline” year-2000 turbofans and an anticipated year-2025 open rotor to quantify the relative fuel-burn benefits. A preliminary scaling with year-2050 “reference” engines, highlights tradeoffs between reduced specific fuel consumption (SFC) and increased engine weight and diameter. These parameters are converted into mission fuel burn variations using linear and nonlinear trade factors (NLTF). The final turbofan has an optimized design-point bypass ratio (BPR) of 16.8, and a maximum overall pressure ratio (OPR) of 75.4, for a 31.5% TOC thrust reduction and a 46% mission fuel burn reduction per passenger kilometer compared to the respective “baseline” engine–aircraft combination. The open rotor SFC is 9.5% less than the year-2025 open rotor and 39% less than the year-2000 turbofan, while the TOC thrust increases by 8% versus the 2025 open rotor, due to assumed increase in passenger capacity. Combined with airframe improvements, the final open rotor-powered aircraft has a 59% fuel-burn reduction per passenger kilometer relative to its baseline.
Generalized SAFE Diagram for Mistuned Bladed Disks
Authors: Neri P. , Bertini L. , Santus C. , Guglielmo A.
Published: October 2019

The Singh's advanced frequency evaluation (SAFE) diagram is a design tool commonly used to find and thus prevent bladed disk resonances, allowing those modal combinations with no match in terms of angular harmonic shape to be neglected. In principle, the SAFE diagram is based on the assumption that the disk structure is perfectly cyclic; hence, any degree of mistuning would prevent its validity. However, each natural mode of a mistuned bladed disk can be expressed as a superimposition of angular harmonic components. The numbers of nodal diameters of these harmonics are extracted as the discrete Fourier transform of the eigenvector. In this paper, a new graphical representation is proposed to account for this complete harmonic content, instead of just a single (main or nominal) number of nodal diameters as in the conventional SAFE diagram. In addition, the relative intensities of the modal components are shown in this generalized SAFE diagram, for an indication of the induced vibrational magnitude of each possible resonance. Numerical and experimental cases are presented, obtaining significant examples of the proposed diagram. Analyzing the signals of an aeromechanical test, unexpected resonances were observed, which were not predicted by the conventional SAFE, but were detected with the proposed diagram.
Experimental Investigation for Enhanced Control of Rotating Unsteady Flow Instabilities in an Unshrouded Centrifugal Compressor Impeller
Authors: Mischo B. , Jenny P. , Bidaut Y. , Fonzi N. , Hermann D. , Wirsum M. C.
Published: October 2019

Unshrouded industrial centrifugal compressor impellers operate at high rotational speeds and volume flow rates. Under such conditions, impeller blade excitation is dominated by high frequency interaction with stationary parts, i.e., vaned diffusers or inlet guide vanes. In a previous study conducted on two full compression units of the original equipment manufacturer (OEM), the authors identified, characterized, and quantified resonant blade vibration caused by the interaction of the impeller blades with rotating stall cells during severe off-design conditions. This caused significant dynamic stress in the blades. In a follow-up study, this phenomenon was reproduced successfully experimentally under representative off-design conditions in a downscaled test rig and numerically with unsteady computational fluid dynamics (CFD) and structural mechanical finite element method (FEM) analysis. The gained knowledge was translated into a new diffuser design philosophy, based on sectorwise circumferential variation of the leading edge angle. This paper presents the patented philosophy, which is experimentally verified on the same test rig configuration in terms of flow path geometry and measurement equipment that was used in the mentioned prior study to assess resonant blade interaction. The results confirm the design aims: rotating stall onset was delayed without affecting the aerodynamic performance of the stage. Resonant blade interaction with rotating stall observed in the baseline diffuser could not be avoided with the two new diffuser designs. However, with the two new diffusers, the induced mechanical stresses in the impeller and the excitability were reduced by up to 12%.
Large-Eddy Simulation and RANS Analysis of the End-Wall Flow in a Linear Low-Pressure Turbine Cascade, Part I: Flow and Secondary Vorticity Fields Under Varying Inlet Condition
Authors: Pichler Richard , Zhao Yaomin , Sandberg Richard , Michelassi Vittorio , Pacciani Roberto , Marconcini Michele , Arnone Andrea
Published: October 2019

In low-pressure turbines (LPTs), around 60–70% of losses are generated away from end-walls, while the remaining 30–40% is controlled by the interaction of the blade profile with the end-wall boundary layer. Experimental and numerical studies have shown how the strength and penetration of the secondary flow depends on the characteristics of the incoming end-wall boundary layer. Experimental techniques did shed light on the mechanism that controls the growth of the secondary vortices, and scale-resolving computational fluid dynamics (CFD) allowed to dive deep into the details of the vorticity generation. Along these lines, this paper discusses the end-wall flow characteristics of the T106 LPT profile at Re = 120 K and M = 0.59 by benchmarking with experiments and investigating the impact of the incoming boundary layer state. The simulations are carried out with proven Reynolds-averaged Navier–Stokes (RANS) and large-eddy simulation (LES) solvers to determine if Reynolds-averaged models can capture the relevant flow details with enough accuracy to drive the design of this flow region. Part I of the paper focuses on the critical grid needs to ensure accurate LES and on the analysis of the overall time-averaged flow field and comparison between RANS, LES, and measurements when available. In particular, the growth of secondary flow features, the trace and strength of the secondary vortex system, and its impact on the blade load variation along the span and end-wall flow visualizations are analyzed. The ability of LES and RANS to accurately predict the secondary flows is discussed together with the implications this has on design.
Thermal Modeling and Performance Analysis of a Hybrid Photovoltaic/Thermal System Under Combined Surface Water Cooling in Winter Season: An Experimental Approach
Authors: Sainthiya Himanshu , Beniwal Narendra Singh
Published: October 2019

In this paper, thermal modeling of a hybrid photovoltaic/thermal (PV/T) system has been developed under combined (front and back) water surface cooling. An analytical expression has been derived for solar cell temperature (Tcs), back surface temperature (Tbs), and overall efficiency (ηOE) of the hybrid PV/T system for the winter condition. Statistical analysis has been performed in the cold climate of MNIT, Jaipur (India), for determining performance parameters of the hybrid PV/T system. An experimental validation has been carried out for the developed thermal model, and fair agreement between the numerical and experimental observations has been observed. We have also calculated the electrical (ηele), thermal (ηth), and overall efficiency (ηOE) as 18.83%, 43.8%, and 64.56%, respectively, and output power as 57.39 mW in the winter condition. We have also noticed that better performance is given by 1.5 LPM out of the four (1, 1.5, 2, and 2.5 LPM) flow rates.
Multiple replication of hierarchical structures from polymer masters with anisotropy
Authors: Mayer Andre , Rond Johannes , Staabs Johannes , Leifels Miriam , Zajadacz Joachim , Ehrhardt Martin , Lorenz Pierre , Sunagawa Hiroki , Hirai Yoshihiko , Zimmer Klaus , Scheer Hella-Christin
Published: October 2019

The copy of structures in the same tone as the original asks at least for a double replication. Each replication generation will suffer from shrinkage of the replication material used, due to curing or thermal contraction. The impact of shrinkage is addressed in a basic study by simulation and experiment. The main replication materials investigated are OrmoStamp and SU-8. Presently, the preparation of anisotropic adhesion elements with hierarchical structures is investigated. The structures are micrometer-sized isolated pads with nanometer-sized self-aligned ripples (laser-induced periodic surface structures) on top. The initial structures are available as isolated photoresist patterns on Si. The double replication of this polymeric master raises questions with respect to its chemical and mechanical stability. The authors report an optimized replication process with an OrmoStamp intermediate template and a final replication in an elastomer. The anisotropic character of the so prepared hierarchical elastomeric adhesion elements is demonstrated by measurement.
Classification of red hind grouper call types using random ensemble of stacked autoencoders
Authors: Ibrahim Ali K. , Zhuang Hanqi , Chérubin Laurent M. , Schärer Umpierre Michelle T. , Ali Ali Muhamed , Nemeth Richard S. , Erdol Nurgun
Published: October 2019

In this paper, a method is introduced for the classification of call types of red hind grouper, an important fishery resource in the Caribbean that produces sounds associated with reproductive behaviors during yearly spawning aggregations. For the undertaken task, two distinct call types of red hind are analyzed. An ensemble of stacked autoencoders (SAEs) is then designed by randomly selecting the hyperparameters of SAEs in the network. These hyperparameters include a number of hidden layers in each SAE and a number of nodes in each hidden layer. Spectrograms of red hind calls are used to train this randomly generated ensemble of SAEs one at a time. Once all individual SAEs are trained, this ensemble is used as a whole to classify call types of red hind. More specifically, the outputs of individual SAEs are combined with a fusion mechanism to produce a final decision on the call type of the input red hind sound. Experimental results show that the innovative approach produces superior results in comparison with those obtained by non-ensemble methods. The algorithm reliably classified red hind call types with over 90% accuracy and successfully detected some calls missed by human observers.
Comparability of the Test of Gross Motor Development–Second Edition and the Test of Gross Motor Development–Third Edition
Authors: Field Stephanie C. , Esposito Bosma Christina B. , Temple Viviene A.
Published: October 2019

When a test is revised, it is important that test users are made aware of the comparability of scores of the new and the original test. We examined how scores on the Test of Gross Motor Development–Second Edition (TGMD-2) and Test of Gross Motor Development–Third Edition (TGMD-3) compared among children in middle childhood. Participants were 270 children recruited in grade 3 (54% female; Mage = 8 years 6 months) and followed through grade 5. Participants completed the skills of both tests. Subtest scores were converted into percent of maximum possible (POMP) scores to facilitate comparison. Although similar, uniformly the TGMD-3 POMP scores were slightly lower. Repeated measures analyses of variance revealed that locomotor subtest scores derived from both tests improved from grade 3 to grade 5, as did TGMD-3 assessed ball skills. However, there was no difference in TGMD-2 assessed object control skills over time. It appears that under-contribution by the underhand roll suppressed the trajectory of improvement of TGMD-2 assessed object control skills. This finding supports the exclusion of the roll from the TGMD-3. The consistent pattern of sex-based differences in TGMD-2 object control skill and TGMD-3 ball skills reinforces the need for male and female norm-reference data for ball skills.
Effects of Physical Activity on the Physical and Psychosocial Health of Youth With Intellectual Disabilities: A Systematic Review and Meta-Analysis
Authors: Kapsal Nathanial J. , Dicke Theresa , Morin Alexandre J.S. , Vasconcellos Diego , Maïano Christophe , Lee Jane , Lonsdale Chris
Published: October 2019

Background: The physical and psychosocial benefits of physical activity for typically developing youth are well established; however, its impact on youth with intellectual disabilities is not as well understood. The aims of this review and meta-analysis were to synthesize the literature and quantify the effects of physical activity on the physical and psychosocial health of youth with intellectual disabilities. Method: Studies meeting the inclusion criteria were grouped by their focus on physical health and/or psychosocial health outcomes. Meta-analyses were performed using 3-level, random effects and mixed effects models. Results: One hundred nine studies met the inclusion criteria. Physical activity had a large effect on physical health (g = 0.773, P < .001) and a moderately large effect (g = 0.682, P < .001) on psychosocial health. Participant age, intellectual disability level, other developmental disabilities, outcome type, and intervention type moderated the effects of physical activity on physical health, whereas study design, risk of bias, other developmental disabilities, outcome type, and intervention type were moderators on psychosocial health. Conclusions: Physical activity has positive effects on the physical and psychosocial health of youth with intellectual disabilities. Although resistance training shows the most physical benefits, teaching movement and sports skills appear to benefit their physical and psychosocial health.
Coordination between stochastic and deterministic specification in the
Drosophila
visual system
Authors: Courgeon Maximilien , Desplan Claude
Published: October 2019

Retinal neurons play musical chairs

As the retina develops in fruit flies, subtypes of certain color photoreceptors, the R7 neurons, are stochastically specified even though the downstream neurons they need to connect to, the Dm8 neurons, are not randomly specified. Courgeon and Desplan find that Dm8 neurons are actually specified in subtypes and are produced in excess. Those Dm8 neurons that connect to an R7 input survive; those that fail to find a match die by apoptosis. The matching is facilitated by a pair of cell adhesion molecules. The stochastic results of R7 differentiation are thus propagated downstream even though those downstream elements are not stochastically determined.

Science
, this issue p.
eaay6727
Safety, Tolerability, and Pharmacokinetics of Oral Nafithromycin (WCK 4873) after Single or Multiple Doses and Effects of Food on Single-Dose Bioavailability in Healthy Adult Subjects
Authors: Iwanowski Piotr , Bhatia Ashima , Gupta Mugdha , Patel Anasuya , Chavan Rajesh , Yeole Ravindra , Friedland David
Published: October 2019

Nafithromycin (WCK 4873), a novel lactone-ketolide, was administered to healthy adult subjects in 2 randomized, double-blind, placebo-controlled, phase 1 studies. In the first-in-human study, single ascending oral doses of nafithromycin (100 to 1,200 mg) were administered to subjects under fasted or fed conditions, with effects of food on bioavailability of nafithromycin studied at the dose levels of 400 and 800 mg.
Tripartite Symbiosis of an Anaerobic Scuticociliate with Two Hydrogenosome-Associated Endosymbionts, a
Holospora
-Related Alphaproteobacterium and a Methanogenic Archaeon
Authors: Takeshita Kazutaka , Yamada Takanori , Kawahara Yuto , Narihiro Takashi , Ito Michihiro , Kamagata Yoichi , Shinzato Naoya
Published: October 2019

Tripartite symbioses between anaerobic ciliated protists and their intracellular archaeal and bacterial symbionts are not uncommon, but most reports have been based mainly on microscopic observations. Deeper insights into the function, ecology, and evolution of these fascinating symbioses involving partners from all three domains of life have been hampered by the difficulties of culturing anaerobic ciliates in the laboratory and the frequent loss of their prokaryotic partners during long-term cultivation. In the present study, we report the isolation of an anaerobic scuticociliate, strain GW7, which has been stably maintained in our laboratory for more than 3 years without losing either of its endosymbionts. Unexpectedly, molecular characterization of the endosymbionts revealed that the bacterial partner of GW7 is phylogenetically related to intranuclear endosymbionts of aerobic ciliates. This strain will enable future genomic, transcriptomic, and proteomic analyses of the interactions in this tripartite symbiosis and a comparison with endosymbioses in aerobic ciliates.
Environmental Surveillance Can Dynamically Track Ecological Changes in Enteroviruses
Authors: Ozawa Hiroki , Yoshida Hiromu , Usuku Shuzo
Published: October 2019

In this study, we showed that environmental enterovirus surveillance can be used to monitor the propagation of nonpolio enteroviruses in addition to poliovirus detection. Since epidemiological studies of virus transmission based on the past were performed using specimens from humans, there were limitations to research design, such as specimen collection for implementation on a large-scale target population. However, environmental monitoring can dynamically track the ecological changes in enteroviruses in the region by monitoring viruses in chronological order and targeting the population within the area by monitoring viruses over time. We observed differences in the transmission of echovirus 11 and coxsackievirus B5 in the region according to lineage in a time-dependent manner and with a multidimensional scaling pattern.
Role of
BGS13
in the Secretory Mechanism of Pichia pastoris
Authors: Naranjo Christopher A. , Jivan Anita D. , Vo Maria N. , de Sa Campos Katherine H. , Deyarmin Jared S. , Hekman Ryan M. , Uribe Christina , Hang Aaron , Her Kai , Fong Michelle M. , Choi Joyce J. , Chou Caroline , Rabara Taylor R. , Myers Gina , Moua Pachai , Thor Der , Risser Douglas D. , Vierra Craig A. , Franz Andreas H. , Lin-Cereghino Joan , Lin-Cereghino Geoff P.
Published: October 2019

The yeast
Pichia pastoris
is used as a host system for the expression of recombinant proteins. Many of these products, including antibodies, vaccine antigens, and therapeutic proteins such as insulin, are currently on the market or in late stages of development. However, one major weakness is that sometimes these proteins are not secreted from the yeast cell efficiently, which impedes and raises the cost of purification of these vital proteins. Our laboratory has isolated a mutant strain of
Pichia pastoris
that shows enhanced secretion of many proteins. The mutant produces a modified version of Bgs13p. Our goal is to understand how the change in the Bgs13p function leads to improved secretion. Once the Bgs13p mechanism is illuminated, we should be able to apply this understanding to engineer new
P. pastoris
strains that efficiently produce and secrete life-saving recombinant proteins, providing medical and economic benefits.
Draft Genome Sequences of Three Isolates of
Coniothyrium glycines
, Causal Agent of Red Leaf Blotch of Soybean
Authors: Blagden Trenna , Espindola Andres , Cardwell Kitty , Ortega-Beltran Alejandro , Bandyopadhyay Ranajit
Published: October 2019

Coniothyrium glycines
, the causal agent of red leaf blotch in soybeans, is considered a high-consequence biological agent. With limited genomic information known, there are no molecular genotyping or detection methods available. We report the draft genome sequences of three
C. glycines
isolates, greatly enhancing our knowledge of this species.
Complete Genome Sequence of an Adenovirus-1 Isolate from an African Pygmy Hedgehog (
Atelerix albiventris
) Exhibiting Respiratory Symptoms in Japan
Authors: Madarame Hiroo , Uchiyama Jumpei , Tamukai Kenichi , Katayama Yukie , Osawa Nanako , Suzuki Kaoru , Mizutani Tetsuya , Ochiai Hideharu
Published: October 2019

This study reports the complete genome sequence of an African pygmy hedgehog adenovirus-1 isolate from an African pygmy hedgehog which displayed respiratory symptoms that included nasal discharge, sniffling, coughing, and respiratory distress. The viral genome is 31,764 bp long and shows four deletion sites compared to that of skunk adenovirus-1.
Complete Genome Sequence of Mycoplasma bovis Strain KG4397, Isolated from Cattle in Japan
Authors: Morimoto Misako , Kenri Tsuyoshi , Ohmori Takashi , Teshima Kaho , Shibuya Kazumoto , Sasakawa Chihiro , Suzuki Masato
Published: October 2019

Mycoplasma bovis
is a major bacterial pathogen that causes pneumonia, mastitis, and arthritis in cattle. In this study, we performed whole-genome sequencing of an
M. bovis
strain isolated in Japan for the first time and announce the complete genome sequence of strain KG4397, which caused respiratory diseases in cattle in 2012.
Complete Coding Sequence of
Andean Potato Mottle Virus
from a 40-Year-Old Sample from Peru
Authors: Adams Ian P. , Fribourg Cesar , Fox Adrian , Boonham Neil , Jones Roger A. C.
Published: October 2019

A complete coding sequence of the type strain of
Andean potato mottle virus
from Peru (isolate Lm) was obtained. Comparison of its RNA1 and RNA2 sequences with variants of this virus isolated in Brazil revealed RNA1 and RNA2 nucleotide identities of 81 to 83% and 70 to 71%, respectively.