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Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method

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Nuclear Science and Techniques 2024年第1期35卷 145-154页

作者： m.Hajipour g.R.Ansarifar Department of Nuclear Engineering Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

Nuclear power plants exhibit non-linear and time-variable dynamics.Therefore,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWR)is a fourth-generation conceptual reactor.In an SCWR,the non-linear dynamics of the reactor require a controller capable of control-ling the nonlinearities.In this study,a pressure-tube-type SCWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled simultaneously.In an SCWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power maneuvering.Reactor point kinetics equations with three groups of delayed neutrons were used in the simulation.Higher-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous studies.The controlled parameters were reactor power,steam temperature,and pressure.Notably,for these parameters,the PI controller had certain instabilities in the presence of disturbances.The classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering phenomenon.HOSmC was highly accurate and stable and had a small computational cost.In reality,it followed the desired values without oscillations and chattering.

关键词： Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model

Periodontitis:An often-neglected complication of diabetes

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World Journal of Diabetes 2024年第3期15卷 318-325页

作者： marina g Kudiyirickal Joseph m Pappachan Primary Care Dental Practice The Smile ClinicPreston PR16PZUnited Kingdom Department of Endocrinology and metabolism Lancashire Teaching Hospitals NHS TrustPreston PR29HTUnited Kingdom Faculty of Science Manchester Metropolitan UniversityManchester M156BHUnited Kingdom Faculty of Biology Medicine and HealthThe University of ManchesterManchester M139PLUnited Kingdom

The bidirectional association between type 2 diabetes mellitus(T2Dm)and periodontitis is now well established,resulting in periodontal disease being considered as the 6th major complication of diabetes mellitus(Dm)after cardiovascular disease,eye disease,neuropathy,nephropathy,and peripheral vascular disease.Dm can worsen the virulence and invasiveness of pathogenic oral microbial flora aggravating the local inflammation and infection in those with periodontal disease.On the other hand,the chemical and immunological mediators released into the circulation as part of periodontal inflammation worsen the systemic insulin resistance with worsening of T2Dm.Periodontitis if undiagnosed or left untreated can also result in eventual tooth loss.A study by Xu et al in the World Journal of Diabetes examined the predictive factors associated with periodontitis in Chinese patients with T2Dm.The prevalence of periodontitis was found to be 75.7%in this study.Based on logistic regression analysis,the predictive factors for higher risk were low tooth brushing frequency[odds ratio(OR)=4.3],high triglycerides(Tg;OR=3.31),high total cholesterol(TC;OR=2.87),higher glycated hem.g.obin(HbA1c;OR=2.55),and higher age(OR=1.05)while higher education level was protective(OR=0.53).However,the most influential variables were HbA1c followed by age,TC,Tg,low education level,brushing frequency,and sex on the random forest model(this model showed higher sensitivity for predicting the risk).A good understanding of the predictors for periodontitis in T2Dm patients is important in prevention,early detection of susceptible patients,and intervention to improve periodontal health and enable long-term.g.ycaemic control as observed by Xu et al.

关键词： Diabetes mellitus Periodontitis Predictive factors Cardiovascular disease glycaemic control

m.g.esium oxide(mgO) nanoadsorbents in wastewater treatment: A comprehensive review

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Journal of m.g.esium and Alloys 2024年第5期12卷 1709-1773页

作者： H.C.S.Perera V.gurunanthanan Anoop Singh m.m.m.g.P.g.mantilaka g.Das Sandeep Arya Department of Physics Khalifa University Postgraduate Institute of Science University of Peradeniya Department of Humanities and Sciences Guru Nanak Institutions Technical Campus Centre for global Health Research Saveetha Medical College and Hospitals Saveetha Institute of Medical and Technical Sciences Department of Physics University of Jammu

Wastewater contamination by heavy metals and synthetic dyes presents a significant environmental challenge, necessitating effective and sustainable separation techniques. This review article provides a detailed examination of m.g.esium oxide(mgO) nanoparticles as an innovative nanoadsorbent for wastewater treatment, with a specific focus on heavy metal and dye removal. The review comprehensively explores various aspects of mgO nanoparticles, including their structural characteristics and synthesis techniques. The article delves into the morphology and crystallographic arrangement of mgO nanoparticles, offering insights into their structural attributes. given the complexity of adsorption processes, the review identifies and analyzes parameters influencing the adsorption efficiency of mgO nanoparticles, such as temperature, pH, contact time, initial concentration, and co-existing ions. The interplay between these parameters and the adsorption capability of mgO nanoparticles emphasizes the importance of optimizing operational conditions. Furthermore, the review assesses various synthesis methods for mgO nanoparticles, including sol-gel, hydrothermal, precipitation, green synthesis, solvothermal, and template-assisted techniques. It discusses the advantages, limitations, and resulting nanoparticle characteristics of each method, enabling readers to grasp the implications of synthesis processes on adsorption efficiency. This comprehensive review consolidates current insights into the effectiveness of mgO nanoparticles as a potent nanoadsorbent for removing heavy metals and dyes from wastewater covering a wide spectrum of aspects related to mgO nanoparticles. moreover, there is a need to investigate the use of mgO in the treatment of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatment applications in real-time.

关键词： mgO nanoparticles Nanoadsorbent Wastewater treatment Heavy metals Dye separation Adsorption Synthesis methods

modeling mitochondria,where are the numbers?

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Neural Regeneration Research 2024年第7期19卷 1435-1436页

作者： Adrian m.Davies Alan g.Holt University Center Shrewsbury ShrewsburyShropshireUK

models and simulations are particularly useful for exploring ideas and concepts in the biological sciences that are expe rimentally impracticable.in silico methods are also gaining acceptance with regulatory authorities as an alternative to animal testing.For example,the Environmental Protection Agency aims to eliminate animal testi ng by 2035.

关键词： eliminate authorities acceptance

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to m.g.etic field in the presence of a shape-dependent trihybrid nanofluid

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Applied mathematics and mechanics(English Edition) 2024年第1期45卷 197-216页

作者： C.g.PAVITHRA B.J.gIREESHA m.L.KEERTHI Department of Pg Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India Department of mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a m.g.etism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTm) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTm) trihybrid nanofluid m.g.etic field

Combination treatment of inflammatory bowel disease:Present status and future perspectives

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World Journal of gastroenterology 2024年第15期30卷 2068-2080页

作者： John K Triantafillidis Constantinos g Zografos manousos m Konstadoulakis Apostolos E Papalois Inflammatory Bowel Disease Unit "Metropolitan General"HospitalHolargos 15562AtticaGreece Hellenic Society for gastrointestinal Oncology 354 Iera OdosChaidari 12461AtticaGreece The 2^(nd)Department of Surgery University of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece Unit of Surgical Research and Training The 2^(nd)Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece

The treatment of patients with inflammatory bowel disease(IBD),especially those with severe or refractory disease,represents an important challenge for the clinical gastroenterologist.It seems to be no exaggeration to say that in these patients,not only the scientific background of the gastroenterologist is tested,but also the abundance of“gifts”that he should possess(insight,intuition,determ-ination,ability to take initiative,etc.)for the successful outcome of the treatment.In daily clinical practice,depending on the severity of the attack,IBD is treated with one or a combination of two or more pharmaceutical agents.These combin-ations include not only the first-line drugs(e.g.,mesalazine,corticosteroids,antibiotics,etc)but also second-and third-line drugs(immunosuppressants and biologic agents).It is a fact that despite the significant therapeutic advances there is still a significant percentage of patients who do not satisfactorily respond to the treatment applied.Therefore,a part of these patients are going to surgery.In recent years,several small-size clinical studies,reviews,and case reports have been published combining not only biological agents with other drugs(e.g.,immunosuppressants or corticosteroids)but also the combination of two biologi-cal agents simultaneously,especially in severe cases.In our opinion,it is at least a strange(and largely unexplained)fact that we often use combinations of drugs in a given patient although studies comparing the simultaneous administration of two or more drugs with monotherapy are very few.As mentioned above,there is a timid tendency in the literature to combine two biological agents in severe cases unresponsive to the applied treatment or patients with severe extraintestinal manifestations.The appropriate dosage,the duration of the administration,the suitable timing for checking the clinical and laboratory outcome,as well as the treatment side-effects,should be the subject of intense clinical research shortly.In this editorial,we attempt to summarize the existing d

关键词： Biologics for immune-mediated conditions Dual-targeted treatment Combination treatment Inflammatory bowel disease Crohn’s

Supposition of graphene stacks to estimate the contact resistance and conductivity of nanocomposites

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Applied mathematics and mechanics(English Edition) 2024年第4期45卷 663-676页

作者： Y.ZARE m.T.mUNIR g.J.WENg K.Y.RHEE Biomaterials and Tissue Engineering Research group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteTehran ***Iran College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait Department of mechanical and Aerospace Engineering Rutgers UniversityNew BrunswickNJ 08903U.S.A. Department of mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

In this study,the effects of stacked nanosheets and the surrounding interphase zone on the resistance of the contact region between nanosheets and the tunneling conductivity of samples are evaluated with developed equations superior to those previously reported.The contact resistance and nanocomposite conductivity are modeled by several influencing factors,including stack properties,interphase depth,tunneling size,and contact diameter.The developed model's accuracy is verified through numerous experimental measurements.To further validate the models and establish correlations between parameters,the effects of all the variables on contact resistance and nanocomposite conductivity are analyzed.Notably,the contact resistance is primarily dependent on the polymer tunnel resistivity,contact area,and tunneling size.The dimensions of the graphene nanosheets significantly influence the conductivity,which ranges from 0 S/m to90 S/m.An increased number of nanosheets in stacks and a larger gap between them enhance the nanocomposite's conductivity.Furthermore,the thicker interphase and smaller tunneling size can lead to higher sample conductivity due to their optimistic effects on the percolation threshold and network efficacy.

关键词： graphene polymer composite stacked nanosheet tunneling conductivity contact resistance interphase

Estimation of Equivalent model of Photovoltaic Array Using Unscented Kalman Filters

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Journal of modern Power Systems and Clean Energy 2024年第3期12卷 819-827页

作者： m.A.gonzález-Cagigal José A.Rosendo-macías A.gómez-Expósito the Department of Electrical Engineering University of Seville IEEE ENgREEN Laboratory of Engineering for Energy and Environmental Sustainability

This paper proposes the use of the unscented Kalman filter to estimate the equivalent model of a photovoltaic(PV) array, using external measurements of current and voltage at the inverter level. The estimated model is of interest to predict the power output of PV plants, in both planning and operation scenarios, and thus improves the efficient operation of power systems with high penetration of renewable energy. The proposed technique has been assessed in several simulated scenarios under different operating conditions. The results show that accurate estimates are provided for the model parameters, even in the presence of measurement noise and abrupt variations under the external conditions.

关键词： mathematical models Estimation Power systems Power system dynamics Kalman filters Parameter estimation Voltage measurement

Highly-sensitive wafer-scale transfer-free graphene mEmS condenser microphones

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microsystems & Nanoengineering 2024年第1期10卷 267-275页

作者： Roberto Pezone Sebastian Anzinger gabriele Baglioni Hutomo Suryo Wasisto Pasqualina m.Sarro Peter g.Steeneken Sten Vollebregt Laboratory of Electronic Components Technology and Materials(ECTM)Department of MicroelectronicsDelft University of TechnologyDelftThe Netherlands Infineon Technologies Ag Am Campeon 1-15Neubiberg 85579Germany Kavli Institue of Nanoscience Department of Quantum NanoscienceDelft University of TechnologyDelftthe Netherlands Department of Precision and microsystems Engineering(PmE) Delft University of TechnologyDelftThe Netherlands

Since the performance of micro-electro-mechanical system(mEmS)-based microphones is approaching fundamental physical,design,and material limits,it has become challenging to improve them.Several works have demonstrated graphene’s suitability as a microphone diaphragm.The potential for achieving smaller,more sensitive,and scalable onchip mEmS microphones is yet to be determined.To address large graphene sizes,graphene-polymer heterostructures have been proposed,but they compromise performance due to added polymer mass and stiffness.This work demonstrates the first wafer-scale integrated mEmS condenser microphones with diameters of 2R=220-320μm,thickness of 7 nm multi-layer graphene,that is suspended over a back-plate with a residual gap of 5μm.The microphones are manufactured with mEmS compatible wafer-scale technologies without any transfer steps or polymer layers that are more prone to contaminate and wrinkle the graphene.Different designs,all electrically integrated are fabricated and characterized allowing us to study the effects of the introduction of a back-plate for capacitive read-out.The devices show high mechanical compliances C_(m)=0.081-1.07μmPa^(−1)(10-100×higher than the silicon reported in the state-of-the-art diaphragms)and pull-in voltages in the range of 2-9.5 V.In addition,to validate the proof of concept,we have electrically characterized the graphene microphone when subjected to sound actuation.An estimated sensitivity of S_(1kHz)=24.3-321 mV Pa^(−1)for a V_(bias)=1.5 V was determined,which is 1.9-25.5×higher than of state-of-the-art microphone devices while having a~9×smaller area.

关键词： transfer plate approaching