bluuebunny/crossref_metadata_2025 huggingface dataset:
A Forward Feedback Control Scheme for a Solar Thermochemical Moving Bed Countercurrent Flow Reactor
Authors: Al Sahlani Assaad , Randhir Kelvin , Ozalp Nesrin , Klausner James
Published: July 2021

Pelletized thermochemical energy storage media has the potential for long duration energy storage. The production of charged solid state energy storage media can be done within a cylindrical cavity chemical reactor that captures concentrated solar radiation from a solar field. Temperature stability of a solar reactor is directly influenced by the solar flux intercepted. This paper presents a low-order physical model to simulate the dynamic response of temperature inside a tubular plug-flow reactor prototype. Solid granular particles are fed to the tube from the top whereas a counter-current flowing gas enters the tube from the bottom. An in-house code was developed to model transient heat transfer of the tube wall, gas, and moving particles. The model was preliminarily validated with packed beds for different temperatures ranges and two gas flow rates. Dynamic response of the reactor temperature is simulated for different input power and gas/particle flow rates. The results show that the system response can be controlled efficiently by utilizing input power (solar flux) as a control parameter. A conventional PI controller is designed to control the temperature inside the reactor and to maintain it during the solar flux intermittency. Controller parameters are tuned using the Ziegler-Nichols method to ensure optimal system response. The results show that the feedback control model is successful in tracking different reference reactor temperatures within reasonable settling time of 30 minutes and eliminated overshoot. This study can be extended to include a hybrid reactor with a multi-input, multi-output variable system.
Effect of Phase Change and Buoyancy-Driven Flows on an ROC-Based Thermal Energy Storage System
Authors: Lee Justin Andrew , Salerno Christopher N. , Girgis Karen U. , Aguirre Ulyses , Baghaei Lakeh Reza
Published: July 2021

Inorganic salts (e.g., chloride salts) have gained attention in the energy field as a new thermal energy storage medium. Low cost, high melting temperature and high heat capacity of inorganic salts make them attractive in utility-scale thermal storage applications as higher energy storage temperatures lead to higher efficiency in power generation. There is a potential to use the dry byproduct of water desalination, i.e., Reverse Osmosis Concentrate (ROC) as a thermal storage medium. Using ROC as a thermal energy storage medium would prevent a harmful waste to be released to the environment while introducing a novel and low-cost alternative for thermal energy storage medium. In this study, heat transfer behavior of an ROC-based thermal energy storage system is studied using CFD. A computational model is developed, verified, and validated to simulate the phase change process and buoyancy-driven flow in a square ROC-based thermal energy storage element. The computational results provide a predictive model for charge and discharge cycles of an ROC-based thermal energy storage system.
Onset of Bénard Convection in an Electromagnetic Heat Exchanger Under Laminar Flow Conditions
Authors: Mohekar Ajit A. , Tilley Burt S. , Yakovlev Vadim V.
Published: July 2021

Electromagnetic (EM) heat exchangers (HX) are critical components in power beaming applications where EM waves are radiated towards an EM HX, which then converts incident energy into heat or mechanical work. An EM HX consists of a lossy ceramic undergoing EM heating, and a fluid flow maintaining thermal contact transfers heat from the ceramic. Temperatures during high-power EM processing of ceramics materials such as zirconia suggest that liquids would be in gaseous phase, so models of EM HX with compressible gas dynamics may provide insights into experimental scenario. As a first step, we consider an EM HX such that plane Poiseuille flow of an incompressible coolant whose density drops linearly with temperature is situated above a lossy ceramic material. Compressible effects are negligible, but density gradients within the fluid can give rise to buoyancy-driven flow under the action of gravity, which may affect the performance of the device. We determine the power of incident waves at which Bénard convection is initiated, through a linear stability analysis, in the fluid layer. We show that in case of temperature dependent ceramic loss factor, perturbations in temperature give rise to an electric (fringe) field which then feeds back into the system promoting the Bénard instability.
A Comparative Study of 1-D and 3-D Simulation Methodologies To Predict the Thermal Performance of a Power Electronics Hardware
Authors: Tiwari Ankit , Whitaker Craig , Kendall Brian
Published: July 2021

Extruded radial fin heat sinks are typically used in power electronics for temperature management. The goal of this study is to compare the temperature predictions of LPTN (Lumped Parameter Thermal Network), Finite element based thermal analysis (using ANSYS Mechanical) and Finite volume based CFD (Computational Fluid Dynamics) & thermal analysis in power electronics hardware. The power electronics hardware under study is used for control of compressors / heaters used in a medical thermal management device. The hardware consists of 2 SCRs (Silicon Controlled Rectifiers) and 2 TRIACs (TRIodes for Alternating Current) arranged in straight in-line configuration with the TRIACs having a higher internal heat generation (1.643E7 W/m3) than the SCRs (4.53E6 W/m3). Each of these four devices is bolted to a separate anodized aluminum heat sink using a TIM (Thermal Interface Material). It was found that CFD based Conjugate Heat Transfer (CHT) analysis with S2S (Surface to Surface) Radiation transfer gave the most accurate thermal predictions (within 6°C). These were comparable to the predictions from 3-D Solid energy equation with uniform convection and S2S radiation. Depending on the availability of computational time and resources, either full CHT study or 3-D Solid energy equation based thermal analysis with uniform convection and S2S radiation is recommended for initial design study.
Numerical Investigation of an Induced Draft Air-Cooled Condenser Under Crosswind Conditions
Authors: Louw Daniel L. , Meyer C. J. , van der Spuy S. J.
Published: July 2021

This study numerically investigated the performance of a 64-fan induced draft Air-Cooled Condenser (ACC) subjected to crosswind conditions. An Actuator Disk Model (ADM) was used to model the axial flow fans and a combination of the Darcy-Forchheimer porosity model and the Effectiveness Number of Transfer Units (ε-NTU) heat transfer model were used to model the heat exchangers. Crosswind conditions were applied to the ACC model in multiple directions and multiple reference velocities, with the results compared to a reference case where no wind was present.

The induced draft ACC attained a mean fan volumetric effectiveness of 1.065, a mean heat transfer effectiveness of 1.039 and a mean heat-to-power ratio of 120.6 when no crosswinds were present. At relatively high crosswind velocities of 9 m/s the mean volumetric effectiveness decreased by 10.1% from wind coming from the primary direction, and by 10.3% from wind coming from the secondary direction. Similarly, the mean heat transfer effectiveness decreased by 21.7% under primary cross-winds, and by 31.3% under secondary crosswinds. Finally, the heat-to-power ratio of the ACC decreased to 92.5 under primary crosswinds, and by 77.6 under secondary crosswinds.
Comparison of Radiation Models for a Turbulent Piloted Methane/Air Jet Flame: A Frozen-Field Study
Authors: David Chloe , Ge Wenjun , Roy Somesh P. , Modest Michael F. , Sankaran Ramanan
Published: July 2021

Numerical modeling of radiative transfer in nongray reacting media is a challenging problem in computational science and engineering. The choice of radiation models is important for accurate and efficient high-fidelity combustion simulations. Different applications usually involve different degrees of complexity, so there is yet no consensus in the community. In this paper, the performance of different radiative transfer equation (RTE) solvers and spectral models for a turbulent piloted methane/air jet flame are studied. The flame is scaled from the Sandia Flame D with a Reynolds number of 22,400. Three classes of RTE solvers, namely the discrete ordinates method, spherical harmonics method, and Monte Carlo method, are examined. The spectral models include the Planck-mean model, the full-spectrum k-distribution (FSK) method, and the line-by-line (LBL) calculation. The performances of different radiation models in terms of accuracy and computational cost are benchmarked. The results have shown that both RTE solvers and spectral models are critical in the prediction of radiative heat source terms for this jet flame. The trade-offs between the accuracy, the computational cost, and the implementation difficulty are discussed in detail. The results can be used as a reference for radiation model selection in combustor simulations.
Thermo-Hydraulic Performance of Heat Sinks With Microchannel Embedded With Pin-fins
Authors: Alkhazaleh Anas , Younes El-Saghir Selim Mohamed , Alnaimat Fadi , Mathew Bobby
Published: July 2021

In this work, an investigation of the heat sink performance employing sinusoidal microchannels embedded with pin fins was conducted. The effect of the sine wave frequency, the pin fins’ diameter, and the hydraulic diameter of the microchannel are studied. The results are quantified in terms of thermal resistance and pressure drop. The study was done using Reynolds numbers varying from 250 to 2000. As Reynolds number increases, the heat sink’s thermal resistance decreased while the pressure drop increased accordingly for all scenarios. The sinusoidal microchannels showed better performance — lower thermal resistance — but with the cost of higher pressure drop compared to the straight microchannel heat sink. The heat sink’s performance was improved by increasing the frequency, diameter of pin fins, and hydraulic diameter; however, this reduction in thermal resistance was associated with an increase in pressure drop. The reduction in thermal resistance of the different configurations of the sinusoidal microchannels was between 17% and 69% compared to the straight microchannel heat sink.
Effect of Geometric Configurations on the Thermal Performance Of Encapsulated PCMs
Authors: Mohaghegh Mohammad Reza , Mahmud Shohel , Tasnim Syeda
Published: July 2021

The integration of thermal energy storage (TES) systems with Phase Change Materials (PCMs) is a promising technique not only for storing thermal energy, also for thermal management applications. Encapsulation is a safe and efficient integration technique of using PCM, which has various advantages such as PCM protection, mechanical stability, leakage prevention and, diversified shapes and sizes. The thermal performance of these systems is heavily dependent on the form and geometry of the encapsulating PCM. Various literature has investigated PCM encapsulation for different applications; however, they were limited to just a few common geometries, i.e., rectangular, spherical, and cylindrical. The present research is aimed to investigate the effect of shape/geometry on the thermal performance of encapsulated PCMs and visualize the PCM melting process to a further improvement in the thermal performance of TES systems for different applications. For this purpose, transient heat transfer and the melting process of the same volume of PCM encapsulated in four different geometrical configurations of the capsules, including the common encapsulation shapes such as spherical, cubical, cylindrical, and conical shape as less studied and new proposed shape, are studied. A mathematical model is developed and numerically solved to study the energy transport processes inside the enclosures. The melting process is visualized numerically to track the solid-liquid interface during the phase change. Moreover, the heat transfer characteristics such as melting fraction and energy stored in the system and their temporal variation during the phase change process are determined. A comparison of the four cases in terms of melting rate and energy storage is carried out, as well. The results show that the conical capsule exhibits the best thermal performance with a total melting time of 72 minutes. While the cubical capsule requires 111 minutes to complete the melting process.
Numerical Thermal Performance Investigation of an Electric Motor Passive Cooling System Employing Phase Change Materials
Authors: Deriszadeh Ali , de Monte Filippo , Villani Marco
Published: July 2021

This study investigates the cooling performance of a passive cooling system for electric motor cooling applications. The metal-based phase change materials are used for cooling the motor and preventing its temperature rise. As compared to oil-based phase change materials, these materials have a higher melting point and thermal conductivity. The flow field and transient heat conduction are simulated using the finite volume method. The accuracy of numerical values obtained from the simulation of the phase change materials is validated. The sensitivity of the numerical results to the number of computational elements and time step value is assessed. The main goal of adopting the phase change material based passive cooling system is to maintain the operational motor temperature in the allowed range for applications with high and repetitive peak power demands such as electric vehicles by using phase change materials in cooling channels twisted around the motor. Moreover, this study investigates the effect of the phase change material container arrangement on the cooling performance of the under study cooling system.
Sun Drying and Far-Infrared Drying Characteristics of Lily
Authors: Yang Pei , Huang Dan , Lv Sisi , Wang Ruiqi , Sherif S. A. , Li Wei
Published: July 2021

The sun drying and far-infrared drying characteristics of lily were experimentally investigated. Fresh lily was blanched and treated with boiling water at 100 °C before drying. The effects of blanching time, drying method and drying temperature on drying rate, nutrient contents (total phenol, total flavonoid and starch contents), hardness and color were analyzed. The results showed that fresh lily without blanching pretreatment had deep browning color, wrinkled skin and long drying time under any drying temperature and drying method. However, the drying rate of samples with blanching pretreatment was significantly increased and the drying time was shortened. The drying rate of solar drying was much lower than that of infrared drying, however the drying quality is better. With the increase of blanching time, the browning degree and the nutrient contents under both drying methods were reduced, while the foaming rate was increased. The hardness after solar drying was moderate, while the hardness of far-infrared drying gradually increased with the increase of drying temperature. The blanching time of 4–6 min was the ideal pretreatment time. Under this pretreatment time, a sample with fair color and moderate hardness and nutrient contents can be obtained under the far-infrared drying temperature of 60–90 °C. The far-infrared drying was more suitable than the sun drying and the most suitable drying process was as follows: fresh lilies were blanched at 100 °C for 5 minutes, and then dried at 70°C for 7.5 hours.
Condensation Heat Transfer Model: A Comparison Study of Condensation Rate Between a Single Bubble and Multiple Rising Bubbles
Authors: Alnaimat Fadi , Alhammadi Omar , Mathew Bobby
Published: July 2021

The main objective of this work is to develop a numerical model to analyze heat transfer and condensation of a rising spherical bubble. The model included the bubble shrinkage during condensation, which can be utilized to analyze the bubble’s total energy loss, raising velocity, and condensation rate of a single bubble compared to multiple bubbles with the same total thermal energy. The equations of motion, heat, and mass transfer were developed. The model results were verified with the bubble condensation experiment data in the literature, in which they exhibited a good agreement.

For the validation, the model results were compared with bubble condensation experiment data in the literature, which showed a good agreement with the experimental results. The dynamic term of the model is developed using the force balance on a gravity-driven bubble, including hydrodynamic drag force and gravity/buoyancy force, which acting with and against the bubble’s motion direction. For the thermal part of the model, a condensation correlation has been adapted to represent the Nusselt number as a function of Reynolds number (Re), Jakob number (Ja), and Prandtl number (Pr). A MATLAB code is developed in order to calculate the instantaneous velocity, the radius, and the mass loss of the vapor bubble in each time step. Moreover, the fundamental behavior for a single bubble and multiple bubbles was investigated in various initial conditions under the same total thermal energy. The effects of the initial bubble radius and the temperature difference between the liquid and vapor phases were analyzed for both scenarios in order to examine the condensation rate. It was found that the thermal behavior of the condensing bubble can be improved by forcing the bubble to collapse into sub bubbles, which will increase the total interfacial area and the rising velocity. Farther, due to generated sub bubbles, the resultant velocity increased the turbulency and the heat transfer rate accordingly. This study can lead to improve the heat transfer rate and allow for more intensive research to enhance the condensation rate.
A Numerical Study on the Thermal Control of Lithium Batteries by Composite Phase Change Materials and Metal Foams
Authors: Buonomo Bernardo , Manca Oronzio , Menale Ferdinando , Moriello Francesco , Mancin Simone
Published: July 2021

This study attempts to control the temperature peaks due to the operation of the battery itself by examining a two-dimensional model to numerically investigate the thermal control of a lithium battery of a commercial electric car. The battery has the dimensions of 8 cm × 31 cm × 67 cm and its capacity is equal to 232 Ah with 5.3 kWh. Thermal control is achieved by means of an internal layer of copper or aluminum foam and phase change material (paraffin), placed on the top of the battery and the external surfaces are cooled by a convective flow. The governing equations, written assuming the local thermal equilibrium for the metal foam, are solved with the finite volume method using the commercial code Ansys-Fluent. Different cases are simulated for different thicknesses of the thermal control system and external convective heat transfer coefficient. The results are given in terms of temperature fields, liquid fraction, surface temperature profiles as a function of time and temperature distributions along the outer surface of the battery for the different cases. In addition, some comparisons with pure PCM are provided to show the advantages of the composite thermal control system with PCM inside the metal foam.
Data Analytics Approach for Understanding the Relationship Between the Thermal and Energy Performance in Ferronickel Large Industrial Rotary Kilns
Authors: Ardila Antonio , Rueda Bernardo , Sánchez Iván , Parra Maricel , Corredor Lesme , González Arturo , Romero Johanna
Published: July 2021

The ferronickel production process closely resembles that of cement and steel. Published studies typically take the developments of the latter and adapt them to ferronickel. However, few open publications allow for a proper understanding of the calcination and reduction of lateritic nickel minerals. This research analyzes the operation of a rotary kiln calciner of 135 m length, a diameter of 6 m, and a mass flow rate between 170 and 180 t/h of partially dry mineral. The calciner uses coal as a reducing agent and natural gas as a thermal energy source. Principal component analysis (PCA) was used in a large industrial dataset to determine the variables with a greater influence on the process performance. Also, k-means clustering is used to locate operation points favorable to calcined mineral production. Results show that the most relevant variables are mineral and gas temperatures and the mass flow rates of air, mineral, natural gas, and coal.
Use of Machine Learning Tools to Assess Surface Dryout During Nucleate and Transition Boiling on Surfaces With Different Wetting and Substrate Properties
Authors: Njike Ursan Tchouteng , Cabrera Samuel , McClure Emma R. , Carey Van P.
Published: July 2021

The work reported in this paper explored the use of machine learning tools to analyze quenching pool boiling data in the nucleate boiling range, near maximum heat flux range, and through the transition boiling range towards the Leidenfrost (minimum heat flux) point. It specifically explores the hypothesis that this sequence is a consequence of progressive dryout of the surface as the wall superheat increases. Machine learning tools are used with a heuristic model of the dryout parametric dependence to extract information about the magnitude of surface dryout as the superheat increases. From experimental data, the machine learning analysis provides an indication of how the dryout transition differs for different surface wetting characteristics and substrate materials. The wetting variations considered ranged from moderately wetted plain aluminum and copper surfaces to highly wetted nanostructured superhydrophilic surfaces. The data examined included aluminum and copper substrates. The results of the machine learning analysis indicate that the properties of the surface substrate can have a significant effect on the progressive surface dryout. In contrast, the surface wetting characteristics had a more limited effect for the surfaces tested. The paper concludes with an assessment of the implications of the findings for developing enhanced surfaces for boiling heat transfer performance.
Pipeline Geohazard Target Susceptibility Threshold – A Reliability-Based Rationalization
Authors: Read Rodney S.
Published: July 2021

Pipeline geohazard assessment involves the delineation and quantification of threat severity associated with a suite of geohazard mechanisms deemed credible for a specific setting or project. The context for a typical assessment is loss of containment from the pipeline — an ultimate limit state (ULS) — considering individual geohazard mechanisms (e.g., landslide, fault displacement, rockfall, subsidence, etc.). To estimate the probability of loss of containment associated with a particular geohazard mechanism at a given location, the evaluation process can be partitioned into an estimate of the probability of occurrence of the geohazard mechanism at that location, and the conditional probability of loss of pipe integrity should the event occur. The product of these two probabilities is termed “susceptibility” expressed as loss of containment events per year at a given location. A typical approach to manage geohazards assessed in this way is to set a target susceptibility threshold to determine mitigation requirements to reduce the estimated susceptibility value for individual geohazards. The rationale for selecting a target susceptibility threshold value has been a topic of interest in recent pipeline projects in Canada. This paper demonstrates a reliability-based approach in rationalizing the selected pipeline geohazard target susceptibility threshold and linking geohazard assessment results to Quantitative Risk Assessment (QRA) of all threat categories in ASME B31-8S.
Swarm robots in science fiction
Authors: Murphy Robin R.
Published: July 2021

In both science and science fiction, robot swarms are out of control.
Outer Membrane Vesicles Derived from
Salmonella enterica
Serotype Typhimurium Can Deliver
Shigella flexneri
2a O-Polysaccharide Antigen To Prevent
Shigella flexneri
2a Infection in Mice
Authors: Tian Huizhen , Li Biaoxian , Xu Tian , Yu Haolin , Chen Jingxuan , Yu Haiyan , Li Shan , Zeng Lingbing , Huang Xiaotian , Liu Qiong
Published: July 2021

Shigella
, the cause of shigellosis or bacillary dysentery, is a major public health concern, especially for children in developing countries. An effective vaccine would control the spread of the disease to some extent.
Fast and Sensitive Real-Time PCR Detection of Major Antiviral-Drug Resistance Mutations in Chronic Hepatitis B Patients by Use of a Predesigned Panel of Locked-Nucleic-Acid TaqMan Probes
Authors: Chu Son V. , Vu Son T. , Nguyen Hang M. , Le Ngan T. , Truong Phuong T. , Vu Van T. T. , Phung Thuy T. B. , Nguyen Anh T. V.
Published: July 2021

We developed a novel real-time PCR assay that simultaneously evaluates 11 major nucleos(t)ide antiviral (NA) drug resistance mutations (mt) in chronic hepatitis B patients (CHB), including L180M, M204I/V, and V207M (lamivudine [LMV] resistance), N/H238A/T (adefovir [ADF] resistance), which are circulating in Vietnam; and T184G/L, S202I, and M250V (entecavir [ETV] resistance) and A194T (tenofovir resistance), which have been recently reported in several studies across the globe. We detected drug-resistant mt in hepatitis B virus (HBV) samples using our predesigned panel of allele-specific locked-nucleic acid (LNA) probes.
Genome-Wide Patterns of Bracovirus Chromosomal Integration into Multiple Host Tissues during Parasitism
Authors: Muller Héloïse , Chebbi Mohamed Amine , Bouzar Clémence , Périquet George , Fortuna Taiadjana , Calatayud Paul-André , Le Ru Bruno , Obonyo Julius , Kaiser Laure , Drezen Jean-Michel , Huguet Elisabeth , Gilbert Clément
Published: July 2021

Bracoviruses are endogenous domesticated viruses of parasitoid wasps that are injected together with wasp eggs into wasp host larvae during parasitism. Several studies have shown that some DNA circles packaged into bracovirus particles become integrated into host somatic genomes during parasitism, but the phenomenon has never been studied using nontargeted approaches.
Kinetic Multi-omic Analysis of Responses to SARS-CoV-2 Infection in a Model of Severe COVID-19
Authors: Cantwell Angelene M. , Singh Harinder , Platt Maryann , Yu Yanbao , Lin Yi-Han , Ikeno Yuji , Hubbard Gene , Xiang Yan , Gonzalez-Juarbe Norberto , Dube Peter H.
Published: July 2021

The current pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has created an urgent need to understand the pathogenesis of this infection. These efforts have been impaired by the lack of animal models that recapitulate severe coronavirus disease 2019 (COVID-19).
Staphylococcal TSST-1 Association with Eczema Herpeticum in Humans
Authors: Schlievert Patrick M. , Roller Richard J. , Kilgore Samuel H. , Villarreal Miguel , Klingelhutz Aloysius J. , Leung Donald Y. M.
Published: July 2021

Atopic dermatitis (eczema, AD) with concurrent herpes simplex virus infection (eczema herpeticum, ADEH) is a severe form of AD. We show that ADEH patients are colonized with
Staphylococcus aureus
that primarily produces the superantigen toxic shock syndrome toxin-1 (TSST-1); however, significantly but to a lesser extent the superantigens staphylococcal enterotoxins A, B, and C are also represented in ADEH.
Transition Phase Regulator AbrB Positively Regulates the
sip1Ab1
Gene Expression in Bacillus thuringiensis
Authors: Shen Xinxin , Yu Qingyue , Liu Huanhuan , Wang Jiaojiao , Zhang Ruibin , Peng Qi , Song Fuping
Published: July 2021

Bacillus thuringiensis
Sip proteins are secreted insecticidal toxins that are toxic to coleopteran pests. In this study, we investigated the transcriptional mechanism of the
sip
gene and showed strong evidence that Sip1Ab1 is secreted in the transition phase and that AbrB, a transition phase regulator that is usually a repressor, positively and directly regulates
sip1Ab1
.
A Novel Small Molecule Inhibits Hepatitis C Virus Propagation in Cell Culture
Authors: Oraby Ahmed K. , Gardner Cassandra L. , Needle Robert F. , Kofahi Hassan M. , Everard Kylie R. , Taylor Nathan G. A. , Rutihinda Suzette G. , Barry Jacqueline P. , Hirasawa Kensuke , Georghiou Paris E. , Russell Rodney S.
Published: July 2021

The discovery of curative antiviral drugs for a chronic disease such as HCV infection has encouraged drug discovery in the context of other viruses for which no curative drugs currently exist. Since we currently face a novel virus that has caused a pandemic, the need for new antiviral agents is more apparent than ever.
Characterization of the GlutathioneS-Transferases Involved in Styrene Degradation in Gordonia rubripertincta CWB2
Authors: Lienkamp Anna C. , Burnik Jan , Heine Thomas , Hofmann Eckhard , Tischler Dirk
Published: July 2021

Styrene is a toxic compound that is used at a large scale by industry for plastic production. Bacterial degradation of styrene is a possibility for bioremediation and pollution prevention.
Synchronization of coupled reaction–diffusion neural networks via intermittent control and saturated impulses
Authors: Cao Zhengran , Li Chuandong , He Zhilong , Zhang Xiaoyu
Published: July 2021

The impulsive synchronization of coupled neural networks with input saturation and the term of reaction–diffusion via a hybrid control strategy is investigated. In this paper, a hybrid controller is proposed, including impulsive controller with input saturation and intermittent controller. This type of hybrid controller can not only solve the periodic and aperiodic intermittent control, lower the update frequency of the controller, but also avoid the saturation phenomenon of impulsive control. Based on linear matrix inequalities (LMIs), and Jensen’s inequality, under a proposed suitable Lyapunov function, a series of sufficient conditions are established to guarantee the stability of the error system. Compared with the recent relevant impulsive saturation results, the polytopic representation method dealing with actuator saturation may make the synchronization criterion more universal and less restrictive. Finally, a numerical example is provided to verify the correctness and feasibility of the theoretical results.
China’s Vision of International Society and its Construction through Incentive Mechanisms: A Community with a Shared Future for Mankind and the Belt and Road Initiative
Authors: Wang Yuzhu , Yi Yin
Published: July 2021

Since the launch of the Belt and Road Initiative (BRI), substantive progress has been achieved through the joint efforts made between China and the collaborative parties, attracting great attention from the international community. However, regarding the relationship between BRI and “a community with a shared future for mankind”, a concept proposed by President Xi Jinping later, the explanations are diversified in the academia. The diversity indicates that a common understanding of this relationship is yet to be reached, calling for a further discussion. This paper argues that “a community with a shared future for mankind” is China’s outlook for the future world facing a period of major change never seen in a century. It is China’s vision of international society but transcends the narrative of international society in the international politics studies, because in the former, each party recognizes the deep interdependence relationships (or a form of shared future) among them and between human and nature, thereby willing to negotiate and cooperate to advance the world’s economic development, deal with conflict of interests and contradictions among states/civilizations, and resolve the dissonance between human and nature. Thus, a peaceful, stable, prosperous, and sustainable world can be created and preserved. In regard to BRI, it is the platform where China constructs a community with a shared future for mankind through incentive mechanisms and applies its vision of international society.
Virtual national workshop: preparation of multimedia modules for physical education teachers in accordance with COVID-19 prevention procedures
Authors: Irfannuddin Muhammad , Laeto Arwan Bin , Zulissetiana Eka Febri , Santoso Budi , Kurniati Ardesy Melizah , Hestiningsih Tyas
Published: July 2021

The COVID-19 pandemic has caused changes in the school learning system. Face-to-face learning shifted to remote learning using multimedia approaches. Online learning created particular difficulties for Physical Education (PE) teachers. Previously, they had to be role models in the teaching of physical activity. A national virtual workshop was conducted to support those teachers as they shift to remote learning. The purpose of the workshop was to provide PE instruction through social media and develop online learning modules. The 3 days of activities consisted of 4 lectures and 6 workshops provided to 177 PE teachers from 32 provinces in Indonesia. Participants were informed about the COVID-19 pandemic, its impact on children, and healthy life during the pandemic. Online applications that were free of charge, easy to use, highly rated, and widely downloaded were also introduced to them. These multimedia applications could help teachers develop and deliver remote learning modules to their students. The workshop supported the teachers as they adapted to interactive distance learning. The workshop also successfully illustrates an innovative distance learning module delivered through multimedia.
Muscle-tendon cross talk during muscle wasting
Authors: Avey Alec M. , Baar Keith
Published: July 2021

In organisms from flies to mammals, the initial formation of a functional tendon is completely dependent on chemical signals from muscles (myokines). However, how myokines affect the maturation, maintenance, and regeneration of tendons as a function of age is completely unstudied. Here we discuss the role of four myokines—fibroblast growth factors (FGF), myostatin, the secreted protein acidic and rich in cysteine (SPARC) miR-29—in tendon development and hypothesize a role for these factors in the progressive changes in tendon structure and function as a result of muscle wasting (disuse, aging, and disease). Because of the close relationship between mechanical loading and muscle and tendon regulation, disentangling muscle-tendon cross talk from simple mechanical loading is experimentally quite difficult. Therefore, we propose an experimental framework that hopefully will be useful in demonstrating muscle-tendon cross talk in vivo. Though understudied, the promise of a better understanding of muscle-tendon cross talk is the development of new interventions that will improve tendon development, regeneration, and function throughout the lifespan.
Identification and Validation of PIK3CA as a Marker Associated with Prognosis and Immune Infiltration in Renal Clear Cell Carcinoma
Authors: Li Ya , Wang Chong , Gao Yang , Zhou Liang
Published: July 2021

Background. Kidney renal clear cell carcinoma (KIRC) is the most prevalent renal malignancy. The therapeutic strategies for advanced KIRC are very few, with only sunitinib being widely approved. Mutations in the PIK3CA gene can affect tumor cell proliferation, metastasis, and patients’ survival. Methods. Bioinformatics analysis was performed to explore the expression and clinical significance of PIK3CA in KIRC. Moreover, qRT-PCR was conducted to verify the result. Results. Subgroup analyses of KIRC tissue based on gender, tumor grade, and cancer stage indicated downregulation of PIK3CA mRNA expression. The KIRC patients with high PIK3CA expression indicated a better overall survival, progression-free survival, and disease-free survival. A predictive nomogram was constructed and demonstrated that the calibration plots for the 3-year and 5-year OS rates were predicted relatively well compared with an ideal model in the TCGA KIRC cohort. The validation study revealed that downregulation of PIK3CA in KIRC tissues and low PIK3CA expression had a poor overall survival with an AUC of 0.775 in the ROC curve. Moreover, Cox regression analysis revealed that PIK3CA expression and clinical stage were independent factors affecting the prognosis of KIRC patients. PIK3CA expression was found to be significantly associated with the abundance of immune cells and immune biomarker sets. PIK3CA and associated genes were found to be mainly associated with immune response and the JAK-STAT signaling pathway. Conclusion. We identified PIK3CA as a potential biomarker for prognosis correlated with immune infiltrates in KIRC. Further studies should focus on the functions of PIK3CA in KIRC carcinogenesis.
Mitochondrial Dysfunction in Chronic Respiratory Diseases: Implications for the Pathogenesis and Potential Therapeutics
Authors: Zhou Wen-cheng , Qu Jiao , Xie Sheng-yang , Sun Yang , Yao Hong-wei
Published: July 2021

Mitochondria are indispensable for energy metabolism and cell signaling. Mitochondrial homeostasis is sustained with stabilization of mitochondrial membrane potential, balance of mitochondrial calcium, integrity of mitochondrial DNA, and timely clearance of damaged mitochondria via mitophagy. Mitochondrial dysfunction is featured by increased generation of mitochondrial reactive oxygen species, reduced mitochondrial membrane potential, mitochondrial calcium imbalance, mitochondrial DNA damage, and abnormal mitophagy. Accumulating evidence indicates that mitochondrial dysregulation causes oxidative stress, inflammasome activation, apoptosis, senescence, and metabolic reprogramming. All these cellular processes participate in the pathogenesis and progression of chronic respiratory diseases, including chronic obstructive pulmonary disease, pulmonary fibrosis, and asthma. In this review, we provide a comprehensive and updated overview of the impact of mitochondrial dysfunction on cellular processes involved in the development of these respiratory diseases. This not only implicates mechanisms of mitochondrial dysfunction for the pathogenesis of chronic lung diseases but also provides potential therapeutic approaches for these diseases by targeting dysfunctional mitochondria.
Pathologic Femur Fracture through Osteoid Osteoma after Radiofrequency Ablation: Case Report and Review of the Literature
Authors: Rogers Nathan B. , Roper Brennan P. , Mansour Alfred A.
Published: July 2021

This is a case report of a 4-year-old girl who sustained a femoral shaft fracture 2 weeks after radiofrequency ablation of an osteoid osteoma. The fracture occurred after a relatively low-energy impact, jumping off the second to last step of a staircase. The pathologic fracture was successfully treated with closed reduction and spica casting, with full return to activities. Cases have been reported in the literature of femoral shaft fractures in older patients after radiofrequency ablation, but all are farther out than 2 weeks and none in patients as young as 4 years.
PL Spectra and Hot Charge Carrier Phenomena in an Undoped GaAs/AlGaAs Tunnel-Coupled Quantum Well
Authors: Jarusirirangsi Kanothai , van Dommelen Paphavee , Daengngam Chalongrat
Published: July 2021

In this research, we experimentally investigated the photoluminescence (PL) spectra of an undoped GaAs/Al0.36Ga0.64As Tunnel-Coupled Quantum Well (TCQW) at 300 K and 77 K. At 300 K, PL spectra were broadened at various laser intensities due to the characteristic quantum-confinement electron levels in the active region of the TCQW during pumping excitation. At 77 K, at selected excitation intensities, the high-energy tails in the PL spectra of the studied structure corresponded with hot electron temperatures as functions of the energy of emitted photons. The average scattering energy rate of hot electrons in the system was also studied at a lattice temperature of 77 K. The average scattering energy rate of hot electrons obtained from this experimental study was in agreement with the calculated theoretical value.
A Sign Logic‐Based Method of Current Sensor Fault Detection for PMSM Drivers
Authors: Guo Chuangqiang , Wu Chunya , Liu Hong
Published: July 2021

A simplified method of current sensor fault detection and isolation (FDI) for permanent magnet synchronous motor (PMSM) drives, which only requires to collect the information of motor positions and currents of the measured phases, has been proposed in this paper. Compared with the classical state‐observer‐based approaches, the calculations needed in the new method only involve a few addition and logical operations. The simplicity and reliability of the new method makes itself especially useful for fault detection of current sensors in real‐time control systems with limited computational capability, e.g., single‐chip microcomputers (SCM) or field programmable gate arrays (FPGA). The experimental results on the basis of a FPGA controller have validated the feasibility and robustness of the proposed FDI approach.
Diffuse Leukoplakia of the Bladder Ostium-Sparing in Patient Treated with Leuprorelin for Breast Cancer
Authors: Nacchia Antonio , di Giacomo Ferdinando , Di Cerbo Arcangelo , Di Somma Massimo Dante , Patitucci Giuseppe , Disabato Giuseppe , Vita Giulia
Published: July 2021

Case. A 55-year-old woman came to our attention in April 2020 referring haematuria, frequency and urgency. The patient referred previous treatment with leuprorelin 3.75 mg/2 ml for breast cancer three years ago. Urine culture was performed and resulted always negative for pathogens. Cystoscopy revealed a whitish plaque lesion on the fundus, dome, trigone, and left lateral wall of the bladder. Histology of the biopsy confirmed the diagnosis of leukoplakia of the bladder. The plan is to follow her up repeating a cystoscopy every three months and biopsy in 6 months. Literature search revealed very little information on pathogenesis and prognosis of this condition due to its rare occurrence. The main objective of our case study was to describe individual situation of a woman affected by diffuse leukoplakia of the bladder ostium-sparing with a previous treatment with leuprorelin 3.75 mg/2 ml for breast cancer and to show safety of follow-up by cystoscopy and biopsy. Conclusions. We showed a case of a woman treated with leuprorelin and with diffuse leukoplakia of the bladder. We support the recommended long-term follow-up and surveillance based on the literature review by cystoscopy with or without biopsy.
Fuzzy Meir-Keeler’s Contraction and Characterization
Authors: Fathi Vajargah Kianoush , Mottaghi Golshan Hamid
Published: July 2021

In this study, a fuzzy Meir-Keeler’s contraction theorem for complete FMS based on George and Veeramani idea is established. Then, we characterize fuzzy Meir-Keeler’s contractions as contractive types induced by functions called fuzzy

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-function. Moreover, we show that the converse of it is true. Finally, we bring some examples and corollaries certify our results and new improvement.
Characterization of Nucleotide Binding ­Site-Encoding Genes in Sweetpotato, Ipomoea batatas(L.) Lam., and Their Response to Biotic and Abiotic Stresses
Authors: Si Zengzhi , Qiao Yake , Zhang Kai , Ji Zhixin , Han Jinling
Published: July 2021

Sweetpotato, Ipomoea batatas (L.) Lam., is an important and widely grown crop, yet its production is affected severely by biotic and abiotic stresses. The nucleotide binding site (NBS)-encoding genes have been shown to improve stress tolerance in several plant species. However, the characterization of NBS-encoding genes in sweetpotato is not well-documented to date. In this study, a comprehensive analysis of NBS-encoding genes has been conducted on this species by using bioinformatics and molecular biology methods. A total of 315 NBS-encoding genes were identified, and 260 of them contained all essential conserved domains while 55 genes were truncated. Based on domain architectures, the 260 NBS-encoding genes were grouped into 6 distinct categories. Phylogenetic analysis grouped these genes into 3 classes: TIR, CC (I), and CC (II). Chromosome location analysis revealed that the distribution of NBS-encoding genes in chromosomes was uneven, with a number ranging from 1 to 34. Multiple stress-related regulatory elements were detected in the promoters, and the NBS-encoding genes’ expression profiles under biotic and abiotic stresses were obtained. According to the bioinformatics analysis, 9 genes were selected for RT-qPCR analysis. The results revealed that IbNBS75, IbNBS219, and IbNBS256 respond to stem nematode infection; Ib­NBS240, IbNBS90, and IbNBS80 respond to cold stress, while IbNBS208, IbNBS71, and IbNBS159 respond to 30% PEG treatment. We hope these results will provide new insights into the evolution of NBS-encoding genes in the sweetpotato genome and contribute to the molecular breeding of sweetpotato in the future.
Renal NKCC2 Is Dual Regulated by the Synergy of 20-HETE and High-Fat Diet in CYP4F2 Transgenic Mice
Authors: Wu Jingjing , Lai Guangrui , Chen Fangjie , Zhang Bijun , Zhao Yanyan
Published: July 2021

Introduction: 20-Hydroxyeicosatetraenoic acid (20-HETE) is the metabolite of cytochrome P450, which modulates blood pressure by inhibiting renal sodium transport. However, the molecular mechanisms underlying the role of 20-HETE in the development of obesity-related hypertension remain unclear, necessitating this study. Methods: Cytochrome P450 4F2 (CYP4F2) transgenic mice fed high-fat diet (HFD) were used as research animal models. The expression of renal ion transport molecules targeted by 20-HETE was evaluated by real-time PCR and Western blot (WB). The regulatory effect of 20-HETE and HFD on renal Na+-K+-2Cl− cotransporter, isoform 2 (NKCC2) was explored by immunoprecipitation, WB, and luciferase assay. Results: A 2-week HFD feeding dramatically decreased protein abundance but increased renal NKCC2 mRNA expression in CYP4F2 transgenic mice. The decrease in NKCC2 protein was demonstrated to be due to ubiquitination induced by the synergy between 20-HETE and HFD. The increased PPAR-γ protein in CYP4F2 transgenic mice fed HFD and the activation of rosiglitazone on the luciferase reporter construct of the NKCC2 promoter demonstrated that the increase in NKCC2 mRNA in CYP4F2 transgenic mice fed HFD was a consequence of elevated PPAR-γ protein induced by the synergy between 20-HETE and HFD. Conclusions: Our data demonstrated that the synergy between 20-HETE and HFD could decrease NKCC2 protein via posttranslational ubiquitination, which was thought to be the main mechanism underlying the short-term effect in response to HFD and might be responsible for the adaptive modulation of renal NKCC2 to resist sodium retention. Moreover, the increased NKCC2 mRNA expression via PPAR-γ-induced transcriptional regulation was thought to be the main mechanism underlying the long-term effect in response to HFD and plays a pivotal role in the development of obesity-related hypertension.
Compliance to School Classroom Norms and Perceived School Climate among Senior High School Students in a Private University in Manila,Philippines
Authors: Ahorro Adrian Miguelle T. , David Ma. Rafaella , Molina Joaquin V. , Pangilinan Aimee Breanna Y. , Arcinas Myla M.
Published: July 2021

This quantitative study aimedto determine the correlation between senior high school Grade 12 students’ perception of school climate and compliance with school classroom normsin a private university in Manila, Philippines. A sample of 249 Grade 12 respondents who were randomly selected answered the online self-administered questionnaire composed of modified scales to explore the two variables, with Cronbach tests exhibiting an acceptable level of internal consistency (perceptions school climate = 0.88, compliance of classroom norms = 0.86). The study found apositive perceptionof school cli-mate (M= 4.19, SD = 0.40)and a very high level of classroom norm compliance (M= 3.40, SD = 0.32) among the respondents. The Pearson R test revealed a significant moderate positive correlation between their perception of school climateand their level of school classroom norm compliance and (r = 0.554, p< 0.001). This implies that their compliance or adherence to school classroom norms increases as their perception of school climate positively increases.