bluuebunny/crossref_metadata_2025_split huggingface dataset:
A brief period of sleep deprivation leads to subtle changes in mouse gut microbiota
Authors: El Aidy Sahar , Bolsius Youri G. , Raven Frank , Havekes Robbert 
Published: September 2019

AbstractNot getting enough sleep is a common problem in our society and contributes to numerous health problems, including high blood pressure, diabetes and obesity. Related to these observations, a wealth of studies has underscored the negative impact of both acute and chronic sleep deprivation on cognitive function. More recently it has become apparent that the gut microbiota composition can be rapidly altered, modulates brain function and is affected by the aforementioned health problems. As such, changes in the microbiota composition may contribute to the behavioural and physiological phenotypes associated with sleep deprivation. It is unclear, however, whether a brief period of sleep deprivation can also negatively impact the gut microbiota. Here, we examined the impact of 5 hr of sleep deprivation on gut microbiota composition of male C57Bl6/J mice. Despite the fact that the overall microbial composition did not change between the control‐ and sleep‐deprived groups, the relative abundance of the Clostridiaceae and Lachnospiraceae were slightly altered in sleep‐deprived animals compared to controls. Together, these data suggest that depriving mice of sleep for 5 hr leads to subtle changes in the gut microbiota composition.
Diagnostic value of a nested polymerase chain reaction for diagnosing cutaneous sporotrichosis from paraffin‐embedded skin tissue
Authors: Hayashi Shujiro , Kaminaga Tomoko , Baba Akiko , Koike Saiko , Koike Masami , Kanno Miki , Ishikawa Satoko , Tsukada Kyoujyu , Suzuki Toshihiro , Hamasaki Yoichiro , Sairenchi Toshimi , Kobashi Gen , Igawa Ken 
Published: September 2019

SummaryBackgroundThe gold standard for diagnosis of cutaneous sporotrichosis involves the isolation of the fungus, Sporothrix, by a culture test. Generally, the sampling for the culture test is performed at the same time as skin biopsy under local anaesthesia. However, the culture test may occasionally return a false negative result.ObjectiveThe aim of our study was to investigate the diagnostic value of a molecular method for diagnosing cutaneous sporotrichosis from formalin‐fixed and paraffin‐embedded (FFPE) tissues.MethodsOver a 30‐year period, we collected 52 cases of cutaneous sporotrichosis from biopsied specimens that had been positively diagnosed by a culture test. A nested PCR specific for Sporothrix detection was applied using FFPE tissue as template. The results were compared with control samples from 79 patients diagnosed with other cutaneous diseases according to histopathological, clinical findings and a cutler test.ResultsOf the 52 patients who were tested positive on the culture test, all cutaneous diseases were detected by PCR. Of the 59 patients in the control group, 58 tested negative by PCR. Under our conditions, the calculated sensitivity of this method was 100%, the specificity was 98.7% and the kappa coefficient was 0.984 (95% CI: 0.953‐1.000).ConclusionsThe specific PCR assay used appears to be a useful tool for the prompt and accurate diagnosis of sporotrichosis. Using this method, it would be possible to diagnose cutaneous sporotrichosis for patients who were suspected of cutaneous sporotrichosis but tested negative on culturing, and for pathologically suspected cutaneous sporotrichosis patients for whom the culture test was not undertaken.
Temporal shifts in iso/anisohydry revealed from daily observations of plant water potential in a dominant desert shrub
Authors: Guo Jessica S. , Hultine Kevin R. , Koch George W. , Kropp Heather , Ogle Kiona 
Published: September 2019

Summary

Plant species are characterized along a spectrum of isohydry to anisohydry depending on their regulation of water potential (Ψ), but the plasticity of hydraulic strategies is largely unknown. The role of environmental drivers was evaluated in the hydraulic behavior of Larrea tridentata, a drought‐tolerant desert shrub that withstands a wide range of environmental conditions.

With a 1.5 yr time‐series of 2324 in situ measurements of daily predawn and midday Ψ, the temporal variability of hydraulic behavior was explored in relation to soil water supply, atmospheric demand and temperature.

Hydraulic behavior in Larrea was highly dynamic, ranging from partial isohydry to extreme anisohydry. Larrea exhibited extreme anisohydry under wet soil conditions corresponding to periods of high productivity, whereas partial isohydry was exhibited after prolonged dry or cold conditions, when productivity was low.

Environmental conditions can strongly influence plant hydraulic behavior at relatively fast timescales, which enhances our understanding of plant drought responses. Although species may exhibit a dominant hydraulic behavior, variable environmental conditions can prompt plasticity in Ψ regulation, particularly for species in seasonally dry climates.
Perioperative anaphylaxis in children: Etiology, time sequence, and patterns of clinical reactivity
Authors: Khaleva Ekaterina , Franz Amber , Garvey Lene Heise , Jay Nicola , Ylescupidez Alyssa , Bahnson Henry T. , du Toit George 
Published: September 2019

AbstractBackgroundPerioperative anaphylaxis (PA) in children is an uncommon but potentially life‐threatening complication associated with anesthesia. Early identification and management of PA is essential to optimize clinical outcomes.MethodsWe performed a retrospective study of anesthesia records from pediatric patients with PA from centers in the United Kingdom, France, and the United States over a period of 10 years. Time sequence of clinical signs and physiological variables during PA were collected, along with results of allergy testing.ResultsTwenty‐nine children with PA were included. Median age was 11 years. Based on the modified Ring and Messmer Grading Scale, severe reactions were seen in 25 (86%) members of this cohort, with 4 (14%) experiencing cardiac arrest. Life‐threatening hypotension was the first clinical sign of PA in 59% of cases, followed by tachycardia and bronchospasm. In 16 (55%) cases, the initial signs of PA involved multiple organ systems. When the initial signs of PA were cardiovascular and/or respiratory, more epinephrine doses were administered. Average time from initial sign of PA to treatment with epinephrine was 6 minutes (SD: 6, range: 1‐25). The causative allergen was identified in 15 patients.ConclusionSevere hypotension is the most common presenting sign of PA in children. Initial cardiovascular and/or respiratory signs are associated with the need for increased epinephrine doses. Further studies should optimize the prediction, identification, and early management of PA in children.
Silica‐associated lung disease: An old‐world exposure in modern industries
Authors: Barnes Hayley , Goh Nicole S.L. , Leong Tracy L. , Hoy Ryan 
Published: September 2019

ABSTRACTDespite silica dust exposure being one of the earliest recognized causes of lung disease, Australia, USA, Israel, Turkey and other countries around the world have recently experienced significant outbreaks of silicosis. These outbreaks have occurred in modern industries such as denim jean production, domestic benchtop fabrication and jewellery polishing, where silica has been introduced without recognition and control of the hazard. Much of our understanding of silica‐related lung disease is derived from traditional occupations such as mining, whereby workers may develop slowly progressive chronic silicosis. However, workers in modern industries are developing acute and accelerated silicosis over a short period of time, due to high‐intensity silica concentrations, oxidative stress from freshly fractured silica and a rapid pro‐inflammatory and pro‐fibrotic response. Appropriate methods of screening and diagnosis remain unclear in these workers, and a significant proportion may go on to develop respiratory failure and death. There are no current effective treatments for silicosis. For those with near fatal respiratory failure, lung transplantation remains the only option. Strategies to reduce high‐intensity silica dust exposure, enforced screening programmes and the identification of new treatments are urgently required.
Analysis of Contacts in Friction Damped Turbine Blades Using Dimensionless Numbers
Authors: Hoffmann Thomas , Panning-von Scheidt Lars , Wallaschek Jörg 
Published: September 2019

Abstract
A novel design approach for friction hysteresis measurements is introduced to simplify the characterization of turbine blade contact dynamics. It makes use of dimensionless numbers of a metallic friction contact undergoing small, periodic displacements. Such contacts are used in turbine blades to lower resonance amplitudes by energy dissipation through friction. Nonetheless, this approach is not limited to this field. The dimensionless numbers for characterization of the contact are derived based on a generic contact that is typical for applications in turbine blades. A dimensionless number can be found that characterizes the contact extensively. Several friction hysteresis measurements are conducted on a special test rig in a systematic manner exploring a large parameter space for the derived dimensionless number. Based on the experiments, it is concluded that the normalized measured friction hysteresis loops show similitude despite being measured with parameters spanning a wide range. It results in the possibility to design friction hysteresis tests for friction damped turbine blades in a simple and representative way.
Surrogate-Assisted Modeling and Robust Optimization of a Micro Gas Turbine Plant With Carbon Capture
Authors: Giorgetti Simone , Coppitters Diederik , Contino Francesco , Paepe Ward De , Bricteux Laurent , Aversano Gianmarco , Parente Alessandro 
Published: September 2019

Abstract
The growing share of wind and solar power in the total energy mix has caused severe problems in balancing the electrical power production. Consequently, in the future, all fossil fuel-based electricity generation will need to be run on a completely flexible basis. Microgas turbines (mGTs) constitute a mature technology which can offer such flexibility. Even though their greenhouse gas emissions are already very low, stringent carbon reduction targets will require them to be completely carbon neutral: this constraint implies the adoption of postcombustion carbon capture (CC) on these energy systems. Despite this attractive solution, an in-depth study along with a robust optimization of this system has not yet been carried out. Hence, in this paper, a typical mGT with exhaust gas recirculation has been coupled with an amine-based CC plant and simulated using the software aspenplus. A rigorous rate-based simulation of the CO2 absorption and desorption in the CC unit offers an accurate prediction; however, its time complexity and convergence difficulty are severe limitations for a stochastic optimization. Therefore, a surrogate-based optimization approach has been used, which makes use of a Gaussian process regression (GPR) model, trained using the aspenplus data, to quickly find operating points of the plant at a very low computational cost. Using the validated surrogate model, a stochastic optimization has been carried out. As a general result, the analyzed power plant proves to be intrinsically very robust, even when the input variables are affected by strong uncertainties.
Optimal Cooling Channel Layout in a Hot Enclosure Subject to Natural Convection
Authors: Yang Sam , Ordonez Juan C. 
Published: September 2019

Abstract
We analyzed the optimal cooling channel layouts emerged from minimizing the total entropy generation ST and mean enclosure temperature T¯ in a hot enclosure subject to natural convection. The conservation of mass, momentum, and energy were solved numerically in two-dimensional (2D) space using the finite element method, and an ant colony optimization algorithm was employed to determine the optimal layouts with respect to the number of cooling channels (N) and Rayleigh number (Ra). The total allocatable cooling channel area was fixed in all cases and thus each channel area decreased with increasing N. Subsequently, we examined the heat transfer and flow characteristics based on temperature field, streamlines, and local Bejan number of each optimum and deduced the following: (1) All optimal channel layouts were symmetric about the vertical enclosure centerline; however, the optima resulting in ST,min and T¯min did not always coincide and depended heavily on the flow configuration dictated by N and Ra; (2) the competing nature between heat transfer and its irreversibility was pronounced at low Ra and N when convection and fluid friction were ineffective; and (3) the first and second law performance improved as N increased in most cases. Furthermore, results verified the global convergence and robustness of the ant colony optimization approach in solving a layout optimization problem with pure natural convection.
Promising Neutron Irradiation Applications at the High Temperature Engineering Test Reactor
Authors: Ho Hai Quan , Honda Yuki , Hamamoto Shimpei , Ishii Toshiaki , Takada Shoji , Fujimoto Nozomu , Ishitsuka Etsuo 
Published: September 2019

Abstract
The high temperature gas-cooled reactor (HTGR) has advantages for irradiation applications such as large space available for irradiation at reflector region and high thermal neutron spectrum with the graphite moderator. High temperature engineering test reactor (HTTR), a prismatic type of the HTGR, has been constructed to establish and upgrade the basic technologies for the HTGRs. Many irradiation regions are reserved in the HTTR to be served as a potential tool for an irradiation test reactor in order to promote innovative basic researches such as materials, fusion reactor technology, and radiation chemistry. This study shows the overview of some possible irradiation applications at the HTTRs including neutron transmutation doping silicon (NTD-Si) and Iodine-125 (125I) productions. The HTTR has possibility to produce about 40 tons of doped Si-particles per year for fabrication of spherical silicon solar cell. Besides, the HTTR could also produce about 1.8 × 105 GBq/yr of 125I isotope, comparing to 3.0 × 103 GBq of total 125I supplied in Japan in 2016.
Research on the Conversion Relationship for Three-Point Bending Specimen With Fixed Constraints in the Large Deformation Stage
Authors: Yu Hai-Yang , Zhou Guo-Yan , Zhuang Fa-Kun 
Published: September 2019

Abstract
In this study, based on the rod tensile model, a conversion relationship between three-point bending specimen with fixed constraints (TPBSF) and uniaxial creep data in the large deformation stage is defined by the reference stress method. Using finite element method, conversion coefficients are determined. Then it is verified by the creep test data of A7N01 at 350 °C (Zhuang, F. K., 2014, “Research on Creep Test Method of Small Specimen Based on Beam Bending Theory,” Ph.D. thesis, East China University of Science and Technology, Shanghai, China). The results show that creep stress exponent n is the same, but creep constant B obtained by rod tensile model is much closer to uniaxial creep than beam bending model. Finally, effects of geometric parameters and friction on conversion coefficients are investigated. On this basis, the specimen cross section aspect ratio greater than 1 and the indenter radius larger than 1 mm are recommended to minimize the influence of TPBSF geometric parameters on conversion coefficients. The influence of friction on conversion coefficients can be negligible.
Effect of Sidewall Conductance on Nusselt Number for Rayleigh-Bénard Convection: A Semi-Analytical and Experimental Correction
Authors: Madanan U. , Goldstein R. J. 
Published: September 2019

Abstract
The effect of sidewall conductance on Nusselt number for the Rayleigh-Bénard convection is examined by performing nearly identical sets of experiments with sidewalls made of three different materials. These experimental results are utilized to extrapolate and estimate the Nusselt number for an ideal zero-thermal-conductivity sidewall case, which is the case when the sidewalls are perfectly insulating. A semi-analytical model is proposed, based on the concept of extended surfaces, to compute the discrepancy in Nusselt number caused by the presence of finite thermal conductance of the sidewalls. The predictions obtained using this model are found to be in good agreement with the corresponding experimentally determined values.
A New Structural Bump Foil Model With Application From Start-Up to Full Operating Conditions
Authors: Arghir Mihai , Benchekroun Omar 
Published: September 2019

Abstract
This paper presents a new structural bump foil model that can handle all operating conditions from start-up to full speed. The model is based on a nonlinear contact algorithm with friction and gaps. The top foil is modeled as a curved beam while bump foil uses a coupled truss model. The model considers the gaps between the bump foil and the bearing casing, between the bump foil and the top foil and between the rotor and the top foil. Thus, any numerical interference between the rotor and the top foil is avoided. A mixed lubrication model is used for the thin film pressures. Following this algorithm, contact pressures appear if the film thickness is less than three times the equivalent roughness of the rotor and of the top foil. Fluid pressures are calculated from numerical solutions of Reynolds equation while contact pressures, if present, are calculated with the model of Greenwood and Williamson. The model is validated by comparisons with the experimental results obtained for start-up operating conditions of a first-generation foil bearing of 38.1 mm diameter with static loads of 10–50 N. Theoretical predictions of the start-up torque and takeoff speed compare well with experimental results. It is also shown how manufacturing bump height errors can explain the differences between theoretical and experimental predictions. Further validations are presented for the same bearing operating at high speeds (30, 45, and 55 krpm) and heavy static loads (up to 200 N). The calculated minimum film thickness and attitude angle are compared with experimental data from the literature.
Numerical Modeling of Nanofluid Thermal Conductivity: The Effect of Nanonetwork on Thermal Transport Behavior
Authors: Ma Binjian , Banerjee Debjoyti 
Published: September 2019

Abstract
Nanofluids have drawn increasing attention in heat transfer applications due to their anomalous enhancement of the thermophysical properties in contemporary literature. Various studies have shown that the addition of minute concentration of the nanoparticles to a base solvent can yield dramatic enhancement of the effective thermal conductivity. A number of parameters have been reported to affect the level of such enhancement such as size, shape, morphology, concentration, and material properties of the nanoparticles. Many different theoretical models have also been proposed in the past literature for predicting the thermal conductivity of nanofluids under different conditions. In general, these models are based on either simplified static composite model or nanoconvection effect considering the Brownian motion of the nanoparticles. However, a few studies have explored the impact of nanoparticle aggregation on the nanofluid thermal conductivity. In particular, the formation of porous percolation structure by the nanoparticles can alter the effective thermal conductivity of nanofluid substantially. In this study, a two-stage numerical simulation is performed to analyze the thermal transport behavior inside nanofluid considering different levels of percolation network formed by the nanoparticles. Based on the simulation results, an empirical model is developed to predict the effective thermal conductivity of nanofluid as a function of nanoparticle size, concentration, and the permeability of nano-aggregation. The results demonstrated a strong dependence of nanofluid thermal conductivity on the nanocluster density, where a looser nanonetwork can yield a significantly higher level of thermal conductivity enhancement under the same particle size and concentration conditions.
Assessing the Sensitivity of Stall-Regulated Wind Turbine Power to Blade Design Using High-Fidelity Computational Fluid Dynamics
Authors: Sanvito Andrea G. , Persico Giacomo , Campobasso M. Sergio 
Published: September 2019

Abstract
This study provides a novel contribution toward the establishment of a new high-fidelity simulation-based design methodology for stall-regulated horizontal axis wind turbines. The aerodynamic design of these machines is complex, due to the difficulty of reliably predicting stall onset and poststall characteristics. Low-fidelity design methods, widely used in industry, are computationally efficient, but are often affected by significant uncertainty. Conversely, Navier–Stokes computational fluid dynamics (CFD) can reduce such uncertainty, resulting in lower development costs by reducing the need of field testing of designs not fit for purpose. Here, the compressible CFD research code COSA is used to assess the performance of two alternative designs of a 13-m stall-regulated rotor over a wide range of operating conditions. Validation of the numerical methodology is based on thorough comparisons of novel simulations and measured data of the National Renewable Energy Laboratory (NREL) phase VI turbine rotor, and one of the two industrial rotor designs. An excellent agreement is found in all cases. All simulations of the two industrial rotors are time-dependent, to capture the unsteadiness associated with stall which occurs at most wind speeds. The two designs are cross-compared, with emphasis on the different stall patterns resulting from particular design choices. The key novelty of this work is the CFD-based assessment of the correlation among turbine power, blade aerodynamics, and blade design variables (airfoil geometry, blade planform, and twist) over most operational wind speeds.
Application of a Graded Approach to Support the National Research Universal Reactor U-2 Experimental Loop Return to Service
Authors: Karam M. 
Published: September 2019

Abstract
The National Research Universal (NRU) reactor at Canadian Nuclear Laboratories (CNL) operated safely for over 60 years and supported a wide range of applications including, testing of fuels and materials under typical power reactor conditions in two experimental loops (U-1 and U-2). Both experimental loops had been taken out of service to address seismic deficiencies. CNL applied a graded approach to successfully return one of these loops, the U-2 Loop to service. The graded approach, without compromising safety, applied a risk informed methodology commensurate to the potential risk posed by the operation of the U-2 Loop. The work enabled the U-2 Loop to resume operation until the NRU reactor was permanently shut down in Mar. 31, 2018, generating valuable data that will be used in the development of advanced nuclear fuels and materials. This paper describes the graded approach employed by CNL that supported U-2 loop return to service (RTS). The use of graded approach is articulated to support development of safety and licensing cases for small modular reactor projects.