bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Surfactants and Nanoparticle Materials on the Stability and Properties of CuO-Water and Fe3O4-Water Nanofluids
Authors: Mane Nikhil S. , Hemadri Vadiraj
Published: September 2020

The arguments in favor of using nanofluids in thermal applications have been increasing substantially for the last few decades. Nanofluids provide improved performance in heat transfer processes in comparison to their base fluids as a result of their superior thermal properties. Even though nanofluids exhibit better thermal properties, their usage has been limited due to their stability issues. The stability of the nanofluid greatly affects its thermal properties over a period of time. The stability and thermal properties of nanofluids can be affected by parameters like surfactants used and their concentrations, and also on the nanomaterial used in the nanofluid. In this study, surfactant material and nanoparticle material are selected as process variables and for each variable two levels are selected. For surfactant material, Sodium Lauryl Sulfate (SLS) and Cetyl Trimethyl Ammonium Bromide (CTAB) are selected. Surfactant concentration ratios are taken as 1:2 for CuO and 1:4 for Fe3O4 material. Four nanofluid samples are prepared with 0.1% weight of nanoparticles and their stability and properties are studied. The feasibility of turbidity as an indicator for stability is also explored in this work.

The results show that the zeta potential and hydrodynamic characteristics are largely dependent on the surfactant material. Both surfactants show good stability of nanofluids. In-line with earlier observations, it is also observed that the nanoparticle material has a dominant effect on the thermal conductivity of the nanofluids. Comparing the turbidity of the nanofluids to the zeta potential, it is observed that the turbidity measurement gives first-hand information about the stability of nanofluids and can act as an index for stability. But still, more exploration is necessary for this field so a quantitive relation can be established between turbidity and zeta potential of different nanofluid materials and concentrations.
Application of the Neural Networks in Prediction of the Thermal Flow on the Jiu River
Authors: Radulescu Victorita
Published: September 2020

Water temperature is an important parameter that influences the life near watercourses. The physical and chemical properties as the density and viscosity, gas solubility in water and in particular of the oxygen, the kinematics of the micro-biological and chemical phenomena affects not only the aquatic life but also the human life and animals living near the watercourse. In the Jiu river is discharged the water coming from the cooling towers of three thermo-electric power plants placed upstream. According to the recent researches realized by the EU Environmental Commission in Romania until 2050 the average temperature could rise by about 2°C. This paper presents the ability of a “neural networks” model to predict the water temperature in the lower part of the Jiu River. A database realized in over nine years in the measuring station Izbiceni, from the Olt County is used, concerning the water temperature (Tw) and the air temperature (Ta). The developed neural network is structured on five input variables and 9 hidden layers, 7 as sub-input and 2 as output. The stochastic time series is based on the separation of values for water Tw and air Ta in seasonal and daily fluctuations components. The schematic structure of the implemented neural network is presented, for obtaining the short-term and the seasonal components of the temperatures. The contact points are adjusted by the method of reprogramming after a gradient algorithm, in order to minimize the quadratic error between the output results and the relevant observed values. The performance of the neural network is based on estimation the thermal changes of the operation mode. For testing the numerical model, the calculations were performed using only the data recorded in nine years, in order to estimate a forecast for the next two years. The results are very close to the experimental recorded data and the obtained errors are less than 0.5°C. At the end of the paper are presented some results, conclusions and references.
Modeling Nanobubble Interactions and Behavior Using Multiphase Lattice Boltzman Methods
Authors: Cooney Alanna Y. , Carey Van P.
Published: September 2020

A multiphase lattice Boltzmann model is used to explore the presence, evolution, and behavior of nanobubbles. The existence and behavior of nanobubbles has been a recent area of interest since the presence of nanobubbles challenges classical nucleation theory which dictates that bubbles below the critical radius should collapse. Nanobubbles have many areas of interest including cleaning of surfaces, nucleate boiling in microchannels, and nucleation on nanostructured materials. Multiphase Lattice Boltzmann methods (LBM) have been demonstrated to be an effective mesoscale approach to modeling multiphase flows and phase-change processes. These methods provide accurate macroscopic results while accounting for microscopic interactions without invoking an extraordinary computational cost. In this study, an LBM is used to model the evolution of nanobubbles with diameters ranging from 5 to 50 nanometers. LBM results are provided for a variety of real physical conditions that are of interest for exploring nanobubble existence within a nanoporous layer. In addition to the single nanobubble analysis, the effects of bubble interaction with smooth surfaces and within nanostructured surfaces are also presented. The results show that the hydrophilic nature of the surfaces is likely the cause of suppression in the onset of nucleate boiling which is often seen in hydrophilic nanoporous layers. The implications of these results on heat transfer applications including multiphase flows and nucleate boiling in roughened nanostructured surfaces are discussed.
A New Design Methodology of Thermal Barrier Coating (TBC) for Internal Combustion Engines
Authors: Singh Chandra Pratap , Taibani Arif , Krishnan Shankar
Published: September 2020

Currently available Internal combustion (IC) engines contribute 25% of the total world energy consumption. IC engines convert only 40% of the fuel energy into the indicated power[1]. Roughly, 30 percent of heat energy is lost from the combustion chamber to the environment. Interest in the design and development of thermal barrier coating (TBC) is increasing due to an increase in fuel costs and due to the decrease in high quality fuel production[2], [3]. The coating materials with low thermal conductivity and high heat capacity led to problems of high surface temperature, which degrade the volumetric efficiency and an increase in the NOx emission. On the other hand, thin TBC of low thermal conductivity and low heat capacity showed high thermal efficiency. Thin coatings could able to prevent intake air heating with effective resistance during the combustion[4].

However, fundamental relationships between thermal efficiency and thermophysical properties, structure, and durability of TBC still need to be investigated. Few studies suggested that the heat interaction study based on the crank angle position could be the best method to estimate the thermodynamics efficiency than the conventionally calculated heat rejection by the adiabatic engine[5], [6].

This work shows a design methodology to develop a thermal barrier coating (TBC), which can reduce heat loss by maintaining the minimum temperature difference between the surface and the in-cylinder gas temperature. The temperature fluctuation of TBC improves the thermal efficiency of internal combustion (IC) engines by reducing the heat loss to the coolant. This work also investigates the thermophysical behaviour of nearby available material and the applicability as a TBC.
Equilibrium Pressure of Liquid Confined in Nanopores Using Molecular Dynamics Simulations
Authors: Zou An , Maroo Shalabh C. , Gupta Manish
Published: September 2020

Liquid in a confined environment or immediate vicinity of a surface is a ubiquitous phenomenon in natural and technological systems. In such circumstances, the intermolecular forces between the liquid and surface cannot be neglected, and therefore the thermodynamic properties of liquid can be significantly different from the bulk. Here we present an investigation of equilibrium pressure in hydrophilic nanopore connected to bulk using molecular dynamics simulations. With similar bulk pressure, negative pressure was observed in 2 nm pore while positive pressure equilibrated in 4 nm pore. Due to wall attraction, liquid atoms were layered near the wall inside the pore, which dominated the pore pressure, no matter if it was negative or positive.
Numerical Analysis of Thermal Stress Development of Steel Slabs in a Pusher-Type Reheat Furnace
Authors: Zambrano Francisco J. Martinez , Worl Bethany , Li Xiang , Silaen Armin K. , Walla Nicholas , Johnson Kurt , Fabina Lawrence , Zhou Chenn
Published: September 2020

During the steelmaking and hot rolling processes, various defects and cracks appear throughout the steel product. These cracks may initiate and grow throughout the hot rolling process and result in a lower quality of the product than is acceptable. The most energy-intensive part of the hot rolling process is the reheating furnace, where slabs are heated up to a target rolling temperature largely through radiant heat transfer. In the reheat furnace, large stresses may develop due to the thermal gradients within the steel product.

A thermal-stress analysis is proposed based on finite element method (FEM) to study the impacts of charging temperature, slab velocity, and heating rate on stress development as the steel slab travels through an industrial pusher-type reheat furnace. Furnace zone information is taken from a previously validated computational fluid dynamics (CFD) model and applied as thermal boundaries and constraints within the thermal-stress FEM models.

Temperature and stress results were taken at the core, top, bottom, top quarter, and the bottom quarter of the steel slab at different residence times. Moreover, temperature lines and contour plots taken along the length of the slab allow visualization of the gradual development of temperature and identification of the locations corresponding to temperature variations as the slabs move in the furnace. The slab temperature predicted by the FEM model was found valid when compared with industrial data. Stress predictions found similar trends with previously published works as well as evidence of thermal shock in the sub-surface near the beginning of the residence time.
A Numerical Analysis on a Solar Chimney With an Integrated Thermal Energy Storage With Phase Change Material
Authors: Buonomo Bernardo , Capasso Lucia , Fatigati Angelo , Manca Oronzio , Nardini Sergio
Published: September 2020

In this paper, a two-dimensional numerical investigation on a prototypal solar chimney system integrated with an absorbing capacity wall in a south facade of a building is presented. The capacity wall is composed of a high absorbing plate and an assigned thickness of phase change material. The chimney consists of a converging channel with one vertical absorbing wall and the glass plate inclined of 2°. The chimney is 5.0 m high, with the channel height equal to 4.0 m, whereas the channel gap is at the inlet equal to 0.34 m and at the outlet it is 0.20 m. The thermal energy storage system is 4.0 m high with a paraffin wax. The transient analysis on a two-dimensional model in airflow is carried out and the governing equations for natural convection in turbulent flow with Boussinesq assumption and thermophysical properties temperature independent are given in terms of k-ε turbulence model. The problem is solved by means of the commercial code Ansys-Fluent using the finite volume method. The numerical analysis was intended to evaluate the thermal and fluid dynamic behavior of the solar chimney integrated with a latent thermal energy storage system for different values of the PCM thickness. The analysis is accomplished at the 21 June by the sunrise to sunset with the chimney oriented towards south. The simulations are performed considering the solar chimney located in Aversa, Italy. Results are given in terms of wall temperature distributions, air velocity and temperature fields and transversal profiles in the channel whereas in terms of liquid fractions, temperature and stream function fields for the phase change material. Thermal and fluid dynamics behaviors are evaluated in order to have some indications to improve the energy conversion system.
Numerical and Experimental Study of Bioink Transfer Process in Laser Induced Forward Transfer (LIFT) 3D Bioprinting
Authors: Qu Jie , Dou Chaoran , Li Jianzhi , Rao Zhonghao , Xu Ben
Published: September 2020

As a promising 3D bioprinting process, laser induced forward transfer (LIFT) has attracted attention in the last decade due to its advantages of non-contact, nozzle-free, high dropping rate and high resolution. However, the mechanism of bubble/jet formation under laser inducement has not been well comprehended yet. To better understand the multiphase process, the bubble formation and jet process under single laser pulse was explored in this study, using both the Computational Fluid Dynamics (CFD) model and experimental study. The results showed that under a laser pulse with the Gaussian distribution, a vapor bubble was formed around 0.1μs, then the bubble was expanded over time. During the bubble expansion process, the maximum magnitude of velocity could reach as high as 22m/s. The pressure near the laser interaction area was around 4.72 × 107 Pa, which is 470 times of the ambient pressure. After increasing the pulse energy and focal spot area, the liquid bubble layer moved downward to complete the bioink transfer process after the collapse of glycerol vapor bubble, which showed similar flow characteristics as the experimental results under the same laser fluence (1.4J/cm2). When the laser fluence was decreased to 0.8 J/cm2, a regular jet flow could be observed. The proposed multiphase numerical model can be used to understand the mechanism of bubble/jet formation under laser inducement and provide some insights into the bioink transfer during LIFT process, in order to eventually optimize the LIFT 3D-printing process with greater cell viability.
Review of Artificial Bubble Generation Techniques and Their Suitability for Phenomenological Boiling Studies
Authors: Dhillon Navdeep Singh
Published: September 2020

The heterogeneous boiling of liquids on hot surfaces, despite its importance, is an extremely complicated and murky phenomenon. It involves the random probabilistic nucleation of multiple bubbles whose growth, interaction, and departure, further, depends on processes involving heat transfer, fluid flow, and interfacial phenomena. This, and the random tumultuous nature of boiling makes experimental studies of the process extremely difficult. For achieving a phenomenological understanding of boiling, several researchers have relied on experiments involving artificially generated bubbles on solid surfaces. In this paper, we evaluate these methods of artificial bubble generation and explore how closely they replicate actual heterogeneous boiling conditions experienced by bubbles. Based on this, we assess the suitability of these methods for conducting phenomenological boiling studies, and identify their potential advantages and drawbacks.
Sensitivity Analysis of Error Motions and Geometric Errors in the Case of Sphere-Shaped Workpiece
Authors: Li Zongze , Sato Ryuta , Shirase Keiichi
Published: September 2020

Motion error of machine tool feed axes influences the machined workpiece accuracy. However, the influences of each error sources are not identical; some errors do not influence the machined surface although some error have significant influences. In addition, five-axis machine tools have more error source than conventional three-axis machine tools, and it is very tough to predict the geometric errors of the machined surface. This study proposes a method to analyze the relationships between the each error sources and the error of the machined surface. In this study, a kind of sphere-shaped workpiece is taken as a sample to explain how the sensitivity analysis makes sense in ball-end milling. The results show that the method can be applied for the axial errors, such as motion reversal errors, to make it clearer to obverse the extent of each errors. In addition, the results also show that the presented sensitivity analysis is useful to investigate that how the geometric errors influence the sphere surface accuracy. It can be proved that the presented method can help the five-axis machining center users to predict the machining errors on the designed surface of each axes error motions.
Bending Simulation of a Shielding Braid Toward its Lifespan Prediction
Authors: Narita Shuhei , Wakamatsu Hidefumi , Morinaga Eiji
Published: September 2020

In this paper, a method to simulate deformation of a shield braid of a cable, which is useful for predicting its lifespan, is proposed. A shield braid in a shielded cable used in a robot may break due to repetitive movement of the robot. For avoiding that, the lifespan of the shield braid must be known. However, fatigue testing to measure its lifespan requires much time and cost. Predicting the lifespan of a shield braid by simulation would reduce such time and cost. As a shield braid is composed of many strands, each strand is modeled based on the differential geometry at first. After that, a method to predict the shape of one strand from that of another strand adjacent is proposed for reduction of computation time. Then, the deformed shape of the whole braid can be simulated when a shield cable is bent. Furthermore, strain at any point on the braid can be estimated from the deformed shape of the braid simulated. Estimated strain is useful for prediction of the lifespan of the braid when the cable is bent repeatedly.
Online-Correction of Robot-Guided Fused Deposition Modeling
Authors: Mewes Gian , Fay Alexander
Published: September 2020

In this paper, a method for online monitoring and correcting robot-guided fused deposition modeling is presented. For development a six-axis industrial robot was equipped with a 3D printing nozzle and used for 3D printing. Additionally, two laser line sensors were mounted next to the printing nozzle at the robot’s flange for capturing process data. By comparing CAD planning data to a point cloud of a workpiece printed with the robot, the measuring accuracy of the system is presented. For online monitoring and correcting, the measurement data of those sensors are analyzed for the unique structure of the edge of the currently printed layer. By detecting this edge, relevant process parameters are identified and compared with the planning data. Based on this comparison, corrections are derived and used for adjusting the robot’s trajectory. Furthermore, a concept for generating comparative measurement data in a simulation environment is presented.
Change Detection in Drilling Process Based on Temperature Nearby Cutting Edge by LSTM Neural Network
Authors: Metheenopanant Punnawit , Suwa Haruhiko , Tokumura Shogo , Murakami Koji , Nonaka Yoshiaki
Published: September 2020

This study considers to efficiently collect “highly value-added” data for in-process anomaly detection of cutting tools in machining processes, and focuses on collection of time-series data of temperature nearby the tool cutting-edge by using a wireless tool holder system composed of an internal temperature measuring device and a wireless transmitter, which is connected with a thermocouple built-in the cutting tool. We then propose a method to detect a change of tool performance based on a recurrent neural network (RNN) with a long short-term memory (LSTM) structure. The capability of the proposed RNN system with LSTM is demonstrated through computational experiments, and demonstrate the time-series data of temperature nearby cutting tool tip is applicable for change detection of cutting tools status.
A Production Planning Based on Shipping Record for Food Company
Authors: Uematsu Hiroya , Sakaguchi Tatsuhiko , Uchiyama Naoki , Hiramatsu Daichi , Hiramatsu Kensuke
Published: September 2020

The production system of the food factory is basically a make-to-stock production. Therefore, to achieve efficient production, the integration of demand, production, and stock information is essential. In this paper, we propose a production planning method based on the demand prediction in order to decrease the stock in the factory of Japanese traditional food ‘Tsukudani’. In the proposed method, the demand is first predicted according to the shipment records, then the material requirement planning and the capacity requirement planning are done based on the demand prediction. Finally, we carry out numerical experiments to validate the effectiveness of the proposed method.
Development of Sensorless Force-Control-Based End-Effector for Automated Robot Polishing
Authors: Tsukada Takuhiro , Ogawa Shotaro , Koto Katsuki , Kakinuma Yasuhiro
Published: September 2020

As the finishing process in manufacturing a fine mold, manual polishing is typically performed to enhance the surface quality. On the other hand, manual polishing causes increase in costs and health damage to the workers due to sucking polishing dusts. Hence, polishing automation is strongly required by utilizing industrial robots. Regarding robot polishing, highly responsive polishing pressure control is definitely needed so that macro-micro system integrating high-performance end-effector into the articulated robot could be an appropriate approach because response of the robot itself is not sufficiently high. From this viewpoint, the purpose of this study is to develop an end-effector having the ability to simultaneously control polishing force and tool spindle speed. The mechanism and control system of the end-effector are designed and experimentally evaluated. In terms of force control, observer-based force control, which does not require any additional force sensor, is implemented. The experimental results show that the developed end-effector successfully control polishing force with 0.1 N and bandwidth up to 23 Hz.
Fuzzy Classification of Gear Fault Using Principal Component Analysis-Based Fuzzy Neural Network
Authors: Zhou Kai , Tang J.
Published: September 2020

Condition assessment of machinery components such as gears is important to maintain their normal operations and thus can bring benefit to their life circle management. Data-driven approaches haven been a promising way for such gear condition monitoring and fault diagnosis. In practical situation, gears generally have a variety of fault types, some of which exhibit continuous severities of fault. Vibration data collected oftentimes are limited to reflect all possible fault types. Therefore, there is practical need to utilize the data with a few discrete fault severities in training and then infer fault severities for the general scenario. To achieve this, we develop a fuzzy neural network (FNN) model to classify the continuous severities of gear faults based on the experimental measurement. Principal component analysis (PCA) is integrated with the FNN model to capture the main features of the time-series vibration signals with dimensional reduction for the sake of computational efficiency. Systematic case studies are carried out to validate the effectiveness of proposed methodology.
Material Model Calibration by Deep Learning for Additively Manufactured Alloys
Authors: Wang Zihan , Xu Hongyi , Li Yang
Published: September 2020

Metal parts manufactured via Powder Bed Fusion (PBF) process show great potential in industrial applications. Hierarchical, heterogeneous microstructure characteristics of the PBF-built alloys pose a significant challenge to the prediction of structural performances. To enable computational engineering of this type of materials, multiscale microstructure modeling framework has been proposed to predict the stochastic material properties. AlSi10Mg built by Selective Laser Melting (SLM) is selected as the demonstrative example. At the microscale, the epitaxial granular structures are reconstructed based on Scanning Electron Microscopic Electron Backscatter Diffraction (SEM EBSD) images. The microscale analysis provides property inputs for the mesoscale model, which captures the fish scale like melt pools at the millimeter scale. The predicted material properties are compared with the experimental data for further calibration of the material constitutive models. One critical challenge is that some parameters in material models cannot be directly obtained from experimental tests. In this work, we establish a machine learning-based model calibration framework to predict the unknown material parameters. Furthermore, several machine learning methods are compared to shed lights on their capability of capturing the relation between input parameter values and the resultant prediction errors.
Smart Production System Modeling: Bernoulli Serial Line Case
Authors: Sun Yuting , Zhu Tianyu , Zhang Liang
Published: September 2020

The manufacturing industry has entered the era of Industry 4.0/Smart Manufacturing. New technologies have dramatically changed the way manufacturing activities are carried out on the factory floor. In addition to an enhanced level of equipment automation, automation of decision-making has been one of the key objectives of these new initiatives. On the other hand, a critical issue that has been overlooked is the construction of mathematical models in manufacturing research and studies, which are typically done manually. This manual, ad-hoc nature of mathematical modeling is quite problematic when modeling the job flow in a manufacturing process. As a result, the quality of the models obtained may heavily depend on the experience and personal preference of the modeler. The goal of this paper is to develop a method to standardize and automate the modeling process using standard manufacturing key performance indices in the framework of Bernoulli serial production line model.
Investigation of a Magnetic-Field-Assisted Stereolithography Process for Printing Functional Part With Graded Materials
Authors: Joyee Erina Baynojir , Pan Yayue
Published: September 2020

Additive manufacturing (AM) has many advantages over traditional fabrication techniques, especially for manufacturing sophisticated structures with intricate architecture. Most AM techniques however are often limited to single material with homogeneous properties. To incorporate multi-functionality in AM fabricated parts, researchers have recently paid much attention to multi-material AM techniques which allow locally programmed material properties. Challenges still remain to manipulate material during AM process for getting desired functionalities in fabricated parts. In this study, we present a novel magnetic-field-assisted stereolithography (M-SL) AM technique capable of printing particle-polymer composites with graded material distributions. This study characterizes process parameters for particle trace development and establishes the relationship between the process and printed properties.
Effects of Curing-Induced Residual Stress on Composite Strength
Authors: Sun Haotian , Zhang Dianyun
Published: September 2020

An integrated processing-damage model was developed to predict the inter-lamina strength of a plain weave composite flange manufactured using the Resin Transfer Molding (RTM) technique. The plain weave composite flange was subjected to four-point bending test to characterize its inter-lamina strength. A Representative Volume Element (RVE) at the fiber–matrix level was established to study the effect of curing-induced residual stress on the resulting composite strength. In order to calculate the residual stress, the curing cycle of the experiment was imposed on the RVE. After fully cured, the RVE was virtually loaded and the cohesive element and Smeared Crack Approach (SCA) were employed to capture the fiber-matrix debonding and matrix cracking responses, respectively. Due to the nature of stress history dependency, the SCA was formulated in the incremental form to reflect the stress buildup. The result shows that both fiber-matrix debonding and matrix cracking can be captured during the virtual loading. However, the load drop in the simulation mainly depends the matrix cracking. As the stress buildup in the matrix is dramatic, it demonstrates that the residual stress has large impact on the composite inter-lamina strength. The numerical methods in this paper can be used as an efficient tool in optimizing the curing process of composite material.
Exact H2 Optimal Solutions to a SDOF System With Electromagnetic Tuned Inerter Damper for Vibration Control
Authors: Luo Yifan , Sun Hongxin , Wang Xiuyong , Chen Anhua , Zuo Lei
Published: September 2020

In order to improve the performance of the tuned mass damper (TMD) with a smaller physical mass for machining vibration suppression and energy harvesting, a dual-functional inerter-based damper, called electromagnetic tuned inerter damper (ETID), is proposed. To evaluate the performance of the ETID, the model of coupled ETID and a single degree of freedom (SDOF) system has been established. The H2 optimal design of the ETID-SDOF system has been conducted, whose goal is to minimize the value of the root mean square (RMS) of the displacement and absolute acceleration of the SDOF system. The analytical solutions of the design parameters of the ETID-SDOF system, namely, frequency ratio and damping ratio, have been derived. The control performance and robustness for the undamped SDOF system with ETID have been evaluated via parametric study compared with the undamped SDOF system with the TMD system. The potential other layouts of the ETID are also discussed. The influence of the structural damping on design parameters and performance has also been investigated.
Tool Path Generation Method for High-Quality Machining of Free-Form Surfaces
Authors: Takanashi Yuki , Aoyama Hideki
Published: September 2020

Machining data (NC program) is generated by a CAM system, which generates the tool path from the target shape as a plane approximation surface instead of a free-form surface. Owing to this plane approximation, machining accuracy is reduced. In this paper, we propose a method to process the shape with high accuracy by defining the areas where accuracy is not required as a plane approximation surface and defining the part where accuracy is required as free-form surfaces.
Experiments on quantum causality
Authors: Goswami K. , Romero J.
Published: September 2020

Quantum causality extends the conventional notion of the fixed causal structure by allowing channels and operations to act in an indefinite causal order. The importance of such an indefinite causal order ranges from the foundational—e.g., towards a theory of quantum gravity—to the applied—e.g., for advantages in communication and computation. In this review, the authors will walk through the basic theory of indefinite causal order and focus on experiments that rely on a physically realizable indefinite causal ordered process—the quantum switch.
The Concurrent Validity of Session-Rating of Perceived Exertion Workload Obtained Face-to-Face Versus Via an Online Application: A Team Case Study
Authors: Fox Jordan L. , O’Grady Cody J. , Scanlan Aaron T.
Published: September 2020

Purpose: To compare the concurrent validity of session-rating of perceived exertion (sRPE) workload determined face-to-face and via an online application in basketball players. Methods: Sixteen semiprofessional, male basketball players (21.8 [4.3] y, 191.2 [9.2] cm, 85.0 [15.7] kg) were monitored during all training sessions across the 2018 (8 players) and 2019 (11 players) seasons in a state-level Australian league. Workload was reported as accumulated PlayerLoad (PL), summated-heart-rate-zones (SHRZ) workload, and sRPE. During the 2018 season, rating of perceived exertion (RPE) was determined following each session via individualized face-to-face reporting. During the 2019 season, RPE was obtained following each session via a phone-based, online application. Repeated-measures correlations with 95% confidence intervals were used to determine the relationships between sRPE collected using each method and other workload measures (PL and SHRZ) as indicators of concurrent validity. Results: Although all correlations were significant (P < .05), sRPE obtained using face-to-face reporting demonstrated stronger relationships with PL (r = .69 [.07], large) and SHRZ (r = .74 [.06], very large) compared with the online application (r = .29 [.25], small [PL] and r = .34 [.22], moderate [SHRZ]). Conclusions: Concurrent validity of sRPE workload was stronger when players reported RPE in an individualized, face-to-face manner compared with using a phone-based online application. Given the weaker relationships with other workload measures, basketball practitioners should be cautious when using player training workloads predicated on RPE obtained via online applications.
Internationalization of the Sport Management Labor Market and Curriculum Perspectives: Insights From Germany, Norway, and Spain
Authors: Wohlfart Olivia , Adam Sandy , García-Unanue Jorge , Hovemann Gregor , Skirstad Berit , Strittmatter Anna-Maria
Published: September 2020

This study applies “Europeanness” to the analysis of internationalization in the sport management labor market and which changes this trend necessitates for sport management curricula. The authors employed an analysis of 30 semistructured interviews with key informants from Germany, Norway, and Spain. The results reveal various effects of internationalization on the sport sector and highlight the richness and diversity in the three countries. Sport management graduates need to possess a diverse set of competencies for successfully starting their careers. In addition to subject-specific knowledge, generic competencies such as the ability to work in a team, being able to communicate in diverse languages, and having intercultural skills are important. The article discusses knowledge of international sport organizations, their governance, global trends, and intercultural and language competencies, as well as international sport event management as identified themes and proposes specific curriculum changes to promote educational outcomes of sport management programs.
Biocrust as one of multiple stable states in global drylands
Authors: Chen Ning , Yu Kailiang , Jia Rongliang , Teng Jialing , Zhao Changming
Published: September 2020

Biocrust alone can be a stable state besides bare soil and vascular plant in global drylands.
First measurements of the radiation dose on the lunar surface
Authors: Zhang Shenyi , Wimmer-Schweingruber Robert F. , Yu Jia , Wang Chi , Fu Qiang , Zou Yongliao , Sun Yueqiang , Wang Chunqin , Hou Donghui , Böttcher Stephan I. , Burmeister Sönke , Seimetz Lars , Schuster Björn , Knierim Violetta , Shen Guohong , Yuan Bin , Lohf Henning , Guo Jingnan , Xu Zigong , Freiherr von Forstner Johan L. , Kulkarni Shrinivasrao R. , Xu Haitao , Xue Changbin , Li Jun , Zhang Zhe , Zhang He , Berger Thomas , Matthiä Daniel , Hellweg Christine E. , Hou Xufeng , Cao Jinbin , Chang Zhen , Zhang Binquan , Chen Yuesong , Geng Hao , Quan Zida
Published: September 2020

The first measurements of the radiation dose on the lunar surface are reported in preparation for human exploration of the Moon.
GADD34 is a modulator of autophagy during starvation
Authors: Gambardella Gennaro , Staiano Leopoldo , Moretti Maria Nicoletta , De Cegli Rossella , Fagnocchi Luca , Di Tullio Giuseppe , Polletti Sara , Braccia Clarissa , Armirotti Andrea , Zippo Alessio , Ballabio Andrea , De Matteis Maria Antonietta , di Bernardo Diego
Published: September 2020

In response to starvation, cells tune protein synthesis to promote autophagy, thus ensuring nutrient recycling and survival.
Platform for micro-invasive membrane-free biochemical sampling of brain interstitial fluid
Authors: Raman Ritu , Rousseau Erin B. , Wade Michael , Tong Allison , Cotler Max J. , Kuang Jenevieve , Lugo Alejandro Aponte , Zhang Elizabeth , Graybiel Ann M. , White Forest M. , Langer Robert , Cima Michael J.
Published: September 2020

Micro-invasive platform performs label-free liquid biopsies of the brain, enabling in vivo tracking of proteins and peptides.
Structure and sequence features of mussel adhesive protein lead to its salt-tolerant adhesion ability
Authors: Ou Xinwen , Xue Bin , Lao Yichong , Wutthinitikornkit Yanee , Tian Ranran , Zou Aodong , Yang Lingyun , Wang Wei , Cao Yi , Li Jingyuan
Published: September 2020

Aromatic and basic residue form pair in intrinsically disordered adhesive protein, and such pairs dominate protein adsorption.
Near-infrared light-triggered NO release for spinal cord injury repair
Authors: Jiang Yaqin , Fu Pengfei , Liu Yanyan , Wang Chaochao , Zhao Peiran , Chu Xu , Jiang Xingwu , Yang Wei , Wu Yelin , Wang Ya , Xu Guohua , Hu Jin , Bu Wenbo
Published: September 2020

Presenting a “pleiotropic messenger” strategy using near-infrared–triggered on-demand NO release for spinal cord injury repair.
Seasonal and Geographical Differences in Total and Pathogenic Vibrio parahaemolyticus and Vibrio vulnificus Levels in Seawater and Oysters from the Delaware and Chesapeake Bays Determined Using Several Methods
Authors: Parveen Salina , Jacobs John , Ozbay Gulnihal , Chintapenta Lathadevi K. , Almuhaideb Esam , Meredith Joan , Ossai Sylvia , Abbott Amanda , Grant Ar'Quette , Brohawn Kathy , Chigbu Paulinus , Richards Gary P.
Published: September 2020

While
V. parahaemolyticus
and
V. vulnificus
cause shellfish-associated morbidity and mortality among shellfish consumers, current regulatory assays for vibrios are complex, time-consuming, labor-intensive, and relatively expensive. In this study, the rapid, simple, and inexpensive COPP assay was identified as a possible alternative to MPN-PCR for shellfish monitoring. This paper shows differences in total
Vibrionaceae
and pathogenic vibrios found in seawater and oysters from the commercially important Delaware and Chesapeake Bays.
Vibrio parahaemolyticus
isolates from the Delaware Bay were more likely to contain commonly recognized pathogenicity genes than those from the Chesapeake Bay.
The Household Resistome: Frequency of β-Lactamases, Class 1 Integrons, and Antibiotic-Resistant Bacteria in the Domestic Environment and Their Reduction during Automated Dishwashing and Laundering
Authors: Schages Laura , Lucassen Ralf , Wichern Florian , Kalscheuer Rainer , Bockmühl Dirk
Published: September 2020

The abundance of antibiotic-resistant bacteria and ARGs is steadily increasing and has been comprehensively analyzed in natural environments, animals, foods, and wastewater treatment plants. In this respect, β-lactams and colistin are of particular interest due to the emergence of multidrug-resistant Gram-negative bacteria. Despite the connection of private households to these environments, only a few studies have focused on the domestic environment so far. Therefore, the present study further investigated the occurrence of ARGs and antibiotic-resistant bacteria in shower drains, washing machines, and dishwashers. The analysis of the domestic environment as a potential reservoir of resistant bacteria is crucial to determine whether households contribute to the spread of ABR or may be a habitat where resistant bacteria from the natural environment, humans, food, or water are selected due to the use of detergents, antimicrobial products, and antibiotics. Furthermore, ABR could limit the options for the treatment of infections arising in the domestic environment.
Potential for Virus Endogenization in Humans through Testicular Germ Cell Infection: the Case of HIV
Authors: Mahé Dominique , Matusali Giulia , Deleage Claire , Alvarenga Raquel L. L. S. , Satie Anne-Pascale , Pagliuzza Amélie , Mathieu Romain , Lavoué Sylvain , Jégou Bernard , de França Luiz R. , Chomont Nicolas , Houzet Laurent , Rolland Antoine D. , Dejucq-Rainsford Nathalie
Published: September 2020

Viruses have colonized the host germ line on many occasions during evolution to eventually become endogenous. Here, we aimed at investigating whether human testicular germ cells (TGCs) can support such viral invasion by studying HIV interactions with TGCs
in vitro
. Our results indicate that isolated primary TGCs express alternative HIV-1 receptors, allowing virion binding but not entry. However, HIV-1 entered and integrated into TGCs upon cell-associated infection and produced low levels of viral proteins.
In vivo
, HIV-1 and SIV DNA was detected in a few TGCs. Molecular landscape analysis showed that TGCs have overall weak antiviral defenses. Altogether, our results indicate that human TGCs can support HIV-1 early replication, including integration, suggesting potential for endogenization in future generations.
Supplemental Material: Pliocene growth of the Dowlatabad syncline in Frontal Fars arc: Folding propagation across the Zagros Fold Belt, Iran
Authors: Najafi Mahdi , al. et
Published: September 2020

Details of the magnetostratigraphy and biostratigraphy results, 87Sr/86Sr ratios, and rheological parameters of numerical modeling are available.
Effects of terrorist attacks on access to maternal healthcare services: a national longitudinal study in Burkina Faso
Authors: Druetz Thomas , Browne Lalique , Bicaba Frank , Mitchell Matthew Ian , Bicaba Abel
Published: September 2020

Introduction

Most of the literature on terrorist attacks’ health impacts has focused on direct victims rather than on distal consequences in the overall population. There is limited knowledge on how terrorist attacks can be detrimental to access to healthcare services. The objective of this study is to assess the impact of terrorist attacks on the utilisation of maternal healthcare services by examining the case of Burkina Faso.

Methods

This longitudinal quasi-experimental study uses multiple interrupted time series analysis. Utilisation of healthcare services data was extracted from the National Health Information System in Burkina Faso. Data span the period of January 2013–December 2018 and include all public primary healthcare centres and district hospitals. Terrorist attack data were extracted from the Armed Conflict Location and Event Data project. Negative binomial regression models were fitted with fixed effects to isolate the immediate and long-term effects of terrorist attacks on three outcomes (antenatal care visits, of facility deliveries and of cesarean sections).

Results

During the next month of an attack, the incidence of assisted deliveries in healthcare facilities is significantly reduced by 3.8% (95% CI 1.3 to 6.3). Multiple attacks have immediate effects more pronounced than single attacks. Longitudinal analysis show that the incremental number of terrorist attacks is associated with a decrease of the three outcomes. For every additional attack in a commune, the incidence of cesarean sections is reduced by 7.7% (95% CI 4.7 to 10.7) while, for assisted deliveries, it is reduced by 2.5% (95% CI 1.9 to 3.1) and, for antenatal care visits, by 1.8% (95% CI 1.2 to 2.5).

Conclusion

Terrorist attacks constitute a new barrier to access of maternal healthcare in Burkina Faso. The exponential increase in terrorist activities in West Africa is expected to have negative effects on maternal health in the entire region.
Impact of regionalisation and case-volume on neonatal and perinatal mortality: an umbrella review
Authors: Walther Felix , Küster Denise Bianca , Bieber Anja , Rüdiger Mario , Malzahn Jürgen , Schmitt Jochen , Deckert Stefanie
Published: September 2020

Objective

This umbrella review summarises and critically appraises the evidence on the effects of regulated or high-volume perinatal care on outcome among very low birth weight/very preterm infants born in countries with neonatal mortality <5/1000 births.

Intervention/exposition

Perinatal regionalisation, centralisation, case-volume.

Primary outcomes

Death.

Secondary outcomes

Disability, discomfort, disease, dissatisfaction.

Methods

On 29 November 2019 a systematic search in MEDLINE and Embase was performed and supplemented by hand search. Relevant systematic reviews (SRs) were critically appraised with A MeaSurement Tool to Assess systematic Reviews 2.

Results

The literature search revealed 508 hits and three SRs were included. Effects of perinatal regionalisation were assessed in three (34 studies) and case-volume in one SR (6 studies). Centralisation has not been evaluated. The included SRs reported effects on ‘death’ (eg, neonatal), ‘disability’ (eg, mental status), ‘discomfort’ (eg, maternal sensitivity) and ‘disease’ (eg, intraventricular haemorrhages). ‘Dissatisfactions’ were not reported. The critical appraisal showed a heterogeneous quality ranging from moderate to critically low. A pooled effect estimate was reported once and showed a significant favour of perinatal regionalisation in terms of neonatal mortality (OR 1.60, 95% CI 1.33–1.92). The qualitative evidence synthesis of the two SRs without pooled estimate suggests superiority of perinatal regionalisation in terms of different mortality and non-mortality outcomes. In one SR, contradictory results of lower neonatal mortality rates were reported in hospitals with higher birth volumes.

Conclusions

Regionalised perinatal care seems to be a crucial care strategy to improve the survival of very low birth weight and preterm births. To overcome the low and critically low methodological quality and to consider additional clinical and patient-reported results that were not addressed by the SRs included, we recommend an updated SR. In the long term, an international, uniformly conceived and defined perinatal database could help to provide evidence-based recommendations on optimal strategies to regionalise perinatal care.

PROSPERO registration number

CRD42018094835.