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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 129-136页

作者： theresa tharakan Dorina Kallogjeri jay F.Piccirillo Department of Otolaryngology-Head and Neck Surgery Clinical Outcomes Research OfficeSchool of MedicineWashington University in St LouisSt LouisMissouriUSA

Objective:to share a single institutional experience with clinical research on COVID-related olfactory dysfunction(OD).Data Source/Method:Narrative review of published original data and ongoing clinical trials on COVID-related OD at Washington University from 2020 to 2023.results:there were three new diagnostic-/patient-reported outcome measures developed and tested.We report five clinical trials of interventions for COVID-related olfactory disorders:combined Visual-Olfactory training(VOLt)with patient-preferred scents versus standard olfactory training(VOLt trial),oral gabapentin versus placebo(Gabapentin for the relief of Acquired Chemosensory Experience trial),nasal theophylline irrigations versus placebo(Smell Changes and Efficacy of Nasal theophylline trial),stellate ganglion block(single-arm),and mindfulness-based stress reduction(MBSr)versus lifestyle intervention(MBSr trial).Conclusions:Initial intervention trials for COVID-related OD have shown potential for improving subjective and objective olfactory outcomes.However,there remains no gold standard treatment that definitively outperforms placebo in controlled trials.therefore,continued investigation of novel therapeutic strategies for COVID-related OD is necessary to maximize olfactory outcomes for affected patients.

关键词： chemosensory disorders COVID olfactory dysfunction

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Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： jay Kumar Shah Hao Wang Said El-Hawwat Centre of Advanced Infrastructure and transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively unexplored.the growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance strategies.this study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE pipe.Laboratory experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch configuration.Mode dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the t(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the t(0,1)mode was developed to trace the extent of simulated crack growth.the findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

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Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: Emphasis on fowl and swine

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Animal Nutrition 2024年第1期16卷 422-428页

作者： Edwin t.Moran Michael r.Bedford Poultry Science Department Auburn University AB Vista Woodstock Court Blenheim Road

Phytin is the Ca2+-Mg2+-K+salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca2+. Even at low gastric pH,phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca2+near the enzyme?s active site further stabilizes its newly formed structure. thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide?s basic amino acids;coordinating free Ca2+, destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca2+and other cations rebind with accessible anions, phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes(e.g. Ca2+, Zn2+) which reduces their structural resistance to autolysis and ability as co-factors(e.g. Zn2+) to increase enzyme activity. Goblet cells initially employ Ca2+as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca2+is progressively displaced by Na+to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer（USWL）. Excessive removal of Ca2+from mucin by phytic acid increases its fluidity facilitating its loss from the USWL with its associated Na+. this partly explains increas

关键词： Digestive enzyme Calcium Endogenous protein Mucin Phytin

Epidemiologic investigation of pediatric distal humerus fractures: An American insurance claims database study

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World Journal of Orthopedics 2024年第1期15卷 52-60页

作者： Kyle jay Klahs Jake E Dertinger Grant t Mello Kevin thapa Alexis B Sandler E'Stephan J Jesus Garcia Nata Parnes Department of Orthopaedic Surgery Texas Tech University Health Sciences-El PasoEl PasoTX 79905United States Medical School California Health Sciences University College of Osteopathic MedicineClovisCA 93611United States Undergraduate School Binghampton UniversityVestalNY 13902United States Department of Orthopaedic Surgery William Beaumont Army Medical CenterFort BlissTX 79918United States Department of Orthopaedic Surgery Carthage Area HospitalCarthageNY 13619United States

BACKGrOUND Distal humerus elbow fractures are one of the most common traumatic fractures seen in pediatric patients and present as three main types:Supracondylar(SC),lateral condyle(LC),and medial epicondyle(ME)fractures.AIM to evaluate the epidemiology of pediatric distal humerus fractures(SC,LC,and ME)from an American insurance claims database.MEtHODS A retrospective review was performed on patients 17 years and younger with the ICD 9 and 10 codes for SC,LC and ME fractures based on the IBM truven MarketScan®Commercial and IBM truven MarketScan Medicare Supplemental databases.Patients from 2015 to 2020 were queried for treatments,patient age,sex,length of hospitalization,and comorbidities.rESULtS A total of 1133 SC,154 LC,and 124 ME fractures were identified.SC fractures had the highest percentage of operation at 83%,followed by LC(78%)and ME fractures(41%).Male patients were,on average,older than female patients for both SC and ME fractures.CONCLUSION In the insurance claims databases used,SC fractures were the most reported,followed by LC fractures,and finally ME fractures.Age was identified to be a factor for how a pediatric distal humerus fractures,with patients with SC and LC fractures being younger than those with ME fractures.the peak age per injury per sex was similar to reported historic central tendencies,despite reported trends for younger physiologic development.

关键词： Supracondylar humerus fracture Lateral condyle fracture Medial epicondyle fracture Pediatric elbow truven Epidemiology

Unsteady MHD Casson Nanofluid Flow Past an Exponentially Accelerated Vertical Plate:An Analytical Strategy

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 431-460页

作者： t.Aghalya r.tamizharasi Department of Mathematics School of Advanced SciencesVellore Institute of TechnologyVelloreTamilnadu632014India

In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHD)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated.the flow was driven by the combined effects of the magnetic field,heat radiation,heat source/sink and chemical reaction.Copper oxide(CuO)and titanium oxide(tiO2)are acknowledged as nanoparticle materials.the nondimensional governing equations were subjected to the Laplace transformation technique to derive closed-form solutions.Graphical representations are provided to analyze how changes in physical parameters,such as the magnetic field,heat radiation,heat source/sink and chemical reaction,affect the velocity,temperature and concentration profiles.the computed values of skin friction,heat and mass transfer rates at the surface were tabulated for various sets of input parameters.It is perceived that there is a drop in temperature due to the rise in the heat source/sink and the Prandtl number.It should be noted that a boost in the thermal radiation parameter prompts an increase in temperature.An increase in the Prandtl number,heat source/sink parameter,time and a decrease in the thermal radiation parameter result in an increase in theNusselt number.the computed values of the skin friction,heat andmass transfer rates at the surface were tabulated for various values of the flow parameters.the present results were compared with those of previously published studies andwere found to be in excellent agreement.this research has practical applications in areas such as drug delivery,thermal medicine and cancer treatment.

关键词： thermal radiation radiative flux nanofluid copper oxide titanium oxide accelerated plate

Conservation laws,Lie symmetries,self adjointness,and soliton solutions for the Selkov–Schnakenberg system

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Communications in theoretical Physics 2024年第2期76卷 29-44页

作者： Kashif Ali Aly r Seadawy Syed t r rizvi Noor Aziz Department of Mathematics COMSATS University IslamabadLahore CampusPakistan Mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-Munawarah41411Saudi Arabia

In this article,we explore the famous Selkov–Schnakenberg(SS)system of coupled nonlinear partial differential equations(PDEs)for Lie symmetry analysis,self-adjointness,and conservation laws.Moreover,miscellaneous soliton solutions like dark,bright,periodic,rational,Jacobian elliptic function,Weierstrass elliptic function,and hyperbolic solutions of the SS system will be achieved by a well-known technique called sub-ordinary differential equations.All these results are displayed graphically by 3D,2D,and contour plots.

关键词： Selkov-Schnakenberg system Lie symmetry analysis conservation laws adjointness integrability

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Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control theory and technology 2024年第2期22卷 326-341页

作者： t.r.Dil Kumar S.J.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

the ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. the system comprises a ball and plate mechanism and a rotary servo unit. the ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. the nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. the simplified nonlinear model of the system is obtained with suitable assumptions. the model is linearized around the operating point using the Jacobian. the validity of the developed models is investigated through correlation function analysis. the open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MAtLAB/Simulink platform. Since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PSO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PSO) PSO PID controller

Getting the Most Out of Every training Day: the Influence of Instructors on Self-regulated Learning During Firefighter Leadership Courses

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International Journal of Disaster risk Science 2024年第3期15卷 332-345页

作者： Stefan r?seler Micha Hilbert Guido Hertel Meinald t.thielsch Department of Psychology University of Münster

Leadership courses in the fire services are highly challenging, and they can seriously exhaust trainees and hamper their selfregulated learning efforts(for example, setting goals, focusing attention, seeking feedback). We theorize that experiences of failure or overload can curtail trainees' available energy resources on subsequent training days, which, in turn, should affect trainees' learning efforts. Given instructors' central role in leadership courses, we hypothesize that supportive and humble instructor behaviors decrease experiences of failure and overload and, thus, increase self-regulated learning. Moreover, we argue that supportive instructor behavior may amplify the positive effects of high energy resources, while humble behavior may alleviate the negative impact of low resource levels. We tested preregistered hypotheses with 118 firefighters participating in two-week leadership courses at a German fire academy. the participants completed short web-based questionnaires before and after classes each day. Multilevel analyses confirmed that perceived daily supportive and humble instructor behavior predicted trainees' reports of daily self-regulated learning activity. Notably, this effect was independent from positive effects of trainees' reported energy resources in the morning. Supportive and humble behavior did not moderate the eff ect of energy resources. Our findings suggest that instructors play a crucial role in facilitating effective learning under challenging training conditions. Furthermore, we offer implications for leaders in fire services, who often conduct trainings with their subordinates.

关键词： Diary study Fire services Instructor behavior Leadership training resource investment

Aerodynamics of a tandem-Bladed Axial Compressor rotor under Circumferential Distortion at Different rotational Speeds

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Journal of thermal Science 2024年第4期33卷 1340-1356页

作者： Amit KUMAr Jerry t.JOHN A.M.PrADEEP r.A.D.AKKErMANS Dragan KOZULOVIC Department of Aerospace Engineering Indian Institute of Technology Bombay Department of Automotive and Aeronautical Engineering Hamburg University of Applied Sciences Institute of Jet Propulsion Bundeswehr University Munich

For most aircraft engines,inflow distortion is inevitable.Inflow distortion is known to degrade the aerodynamic performance and stable operating limits of a compressor.tandem rotor configuration is an arrangement that effectively controls the growth of the boundary layer over the suction surface of the blade.therefore,a higher total pressure rise can be achieved through this unconventional design approach involving the splitting of the blade into forward and aft sections.It is expected that the effect of inlet flow distortion would be more severe for a tandem-rotor design due to the greater flow turning inherent in such designs.However,this aspect needs to be thoroughly examined.the present study discusses the effect of circumferential distortion on the tandem-rotor at different rotational speeds.Full-annulus rANS simulations using ANSYS CFX are used in the present study.the performance of the rotor at a particular flow coefficient and different rotational speeds is compared.the total pressure and efficiency are observed to drop at lower mass flow rates under the influence of circumferential distortion.the loss region in each blade passage is mainly associated with the blade wake,tip leakage vortex,secondary flow,and boundary layer.However,their contribution varies from passage to passage,particularly in the distorted sector.At the lower span,the wake width is found to be higher than that at a higher span.Due to the redistribution of the mass flow,the circumferential extent reduces at a higher span.In the undistorted sector,the strength of the tip leakage vortex is significantly higher at the design rotational speed than at lower speeds.the distortion near the tip region promotes an early vortex breakdown even at the design operating condition.this adversely affects the total pressure,efficiency,and stall margin.Under clean flow conditions,this phenomenon is only observed near the stall point.At the design operating condition,the breakdown of the forward rotor tip leakage vortex is detected in four blade passages

关键词： tandem rotor circumferential distortion loss tip leakage vortex vortex breakdown diffusion factor aerodynamics of compressor blade