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Journal of Palaeogeography 2024年第1期13卷 54-79页

作者： Mehdi Hadi Lorenzo Consorti ali Bahrami Mohammad Parandavar Saeed Khorramdel Department of Geology Faculty of SciencesUniversity of IsfahanIsfahanIran Institute of Marine Sciences(ISMAR-CNR) Area Science ParkBasovizza34149 TriesteItaly National Iranian Oil Company Exploration DirectorateSheikh Bahaei SquareTehranIran Department of Geology Faculty of ScienceFerdowsi University of MashhadMashhadIran

Precise taxonomy and the chronostratigraphic calibration of the Middle Eocene Alveolina from Central Iran is here undertaken from the Chah-Talkh section of the southern Sabzevar region(Central Iran). We have identified Alveolina kieli, Alveolina stercusmuris and Alveolina nuttalli along with the new species Alveolina ozcani n. sp. that we include into the Alveolina elliptica group. We have also found Nummulites uroniensis, Nummulites obesus and Nummulites cf. verneuili and associated calcareous nannofossils that look reliable to make thoughtful correlations with the Shallow Benthic Zones(SBZ). The foraminiferal biostratigraphy suggests an assignment to the upper part of the lower Lutetian-lower part of the middle Lutetian,SBZ13(Middle Eocene), further strengthened through the identification of the calcareous nannofossil NP14b-NP15b or CNE8-CNE10 biozones, providing a solid correlation with the global stratigraphic standards.

关键词： Alveolina Calcareous nannofossil Central neo-tethys Central Iran Middle Eocene Biostratigraphy

Sacrificial piles as a countermeasure against local scour around underwater pipelines

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Water Science and Engineering 2024年第2期17卷 187-196页

作者： Forough Raeisi Seyed Mohammad ali Zomorodiann Masih Zolghadr Hazi Mohammad Azamathulla Department of Water Engineering Shiraz UniversityShiraz ***Iran Department of Water Sciences Engineering Jahrom UniversityJahrom ***Iran Department of Civil and Environmental Engineering The University of the West IndiesSt.Augustine CampusTrinidad 331310Republic of Trinidad and Tobago

Local scour around pipelines crossing rivers or in marine environments is a significant concern.It can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial piles.Three sizes of sacrificial piles were examined in a linear arrangement.Sacrificial piles were installed on the upstream side of the pipeline at three distances.Maximum scour depth reduction rates below the pipeline were computed.The results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the pipeline.This sediment accumulation reduced the scour depth beneath the pipeline.Analysis of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of D.For the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar conditions.For the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles.

关键词： Clear water River crossing pipeline Local scour Self-burial process Sediment transport

Modeling displacement flow inside a full-length casing string for well cementing

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Petroleum Research 2024年第1期9卷 1-16页

作者： Hu Dai ali Eslami Jason Schneider Gefei Liu Fred Schwering Pegasus Vertex Inc.USA Laval University Canada Sanjel Energy Services Canada Athabasca Oil Corporation Canada

While computer modeling of annular displacement efficiency is widely applied in cementing engineering,modeling the displacement flow inside a casing or drill string for cementing operations has received less attention.Although predicting displacement efficiency inside a full-length pipe is desired by cementing engineers,the attempt of developing a model with both efficiency and accuracy faces challenges.Access to computer simulators for this purpose is limited.Compared with annular flow,the displacement flow inside pipe,although within a simpler geometry and without eccentricity effect,is not simpler in physics,modelling strategy and predictability,because a variety of flow patterns and flow instabilities can develop to create complicated fluid interfaces.In this paper,we present an integrated numerical model developed to simulate displacement flows inside a full-length pipe,which connects an existing annulus model to enable complete displacement simulations of cementing jobs.The model uses three-dimensional grid to solve fluid concentrations with degrees of mixing,and incorporates flow instability detection and flow regime determination.Applied in cementing,the model accounts for effects of pumping rate,well inclination,pipe rotation,fluid densities,rheological parameters and more.This computationally efficient model does not rely on high-resolution mesh as often required by conventional Computational Fluid Dynamics models,thus it is suitable to be implemented in a cementing software for daily use by well cementing engineers.The methodology of the model is discussed in detail in this paper.To validate the model,we examine simulation results against experimental results obtained in our laboratory tests and CFD simulations;acceptable agreement is found under different testing conditions.We also presented two case studies of real cementing jobs with cement evaluation logs compared to simulation results,showing that the model can predict consistent displacement efficiency results.

关键词： Inside pipe displacement Displacement efficiency Numerical model Primary cementing Displacement flow

Approach to traumatic cardiac arrest in the emergency department: a narrative literature review for emergency providers

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World Journal of Emergency Medicine 2024年第1期15卷 3-9页

作者： Rashed Alremeithi Quincy K.Tran Megan T.Quintana Soroush Shahamatdar ali Pourmand Department of Emergency Medicine George Washington University School of Medicine and Health SciencesWashington DC 20037USA Department of Emergency Medicine University of Maryland School of MedicineBaltimore 21201USA Program in Trauma the R Adams Cowley Shock Trauma CenterUniversity of Maryland School of MedicineBaltimore 21201USA Center for Trauma and Critical Care Department of Surgerythe George Washington University School of Medicine&Health SciencesWashington DC 20037USA

BACKGROUND:Traumatic cardiac arrest(TCA)is a major contributor to mortality and morbidity in all age groups and poses a significant burden on the healthcare system.Although there have been advances in treatment modalities,survival rates for TCA patients remain low.This narrative literature review critically examines the indications and eff ectiveness of current therapeutic approaches in treating TCA.METHODS:We performed a literature search in the PubMed and Scopus databases for studies published before December 31,2022.The search was refi ned by combining search terms,examining relevant study references,and restricting publications to the English language.Following the search,943 articles were retrieved,and two independent reviewers conducted a screening process.RESULTS:A review of various studies on pre-and intra-arrest prognostic factors showed that survival rates were higher when patients had an initial shockable rhythm.There were conflicting results regarding other prognostic factors,such as witnessed arrest,bystander cardiopulmonary resuscitation(CPR),and the use of prehospital or in-hospital epinephrine.Emergency thoracotomy was found to result in more favorable outcomes in cases of penetrating trauma than in those with blunt trauma.Resuscitative endovascular balloon occlusion of the aorta(REBOA)provides an advantage to emergency thoracotomy in terms of occupational safety for the operator as an alternative in managing hemorrhagic shock.When implemented in the setting of aortic occlusion,emergency thoracotomy and REBOA resulted in comparable mortality rates.Veno-venous extracorporeal life support(V-V ECLS)and veno-arterial extracorporeal life support(V-A ECLS)are viable options for treating respiratory failure and cardiogenic shock,respectively.In the context of traumatic injuries,V-V ECLS has been associated with higher rates of survival to discharge than V-A ECLS.CONCLUSION:TCA remains a signifi cant challenge for emergency medical services due to its high morbidity and mortality rates.Pre-and intra-arres

关键词： Traumatic cardiac arrest Emergency thoracotomy Resuscitative endovascular balloon occlusion of the aorta

Acoustofluidic separation of prolate and spherical micro-objects

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Microsystems & Nanoengineering 2024年第1期10卷 217-230页

作者： Muhammad Soban Khan Mushtaq ali Song Ha Lee Keun Young Jang Seong Jae Lee Jinsoo Park Department of Mechanical Engineering Chonnam National University77 Yongbong-roBuk-guGwangju 61186Republic of Korea Department of Polymer Engineering The University of Suwon17 Wauan-gilBongdam-eupHwaseongGyeonggi 18323Republic of Korea

Most microfluidic separation techniques rely largely on object size as a separation marker.The ability to separate micro-objects based on their shape is crucial in various biomedical and chemical assays.Here,we develop an ondemand,label-free acoustofluidic method to separate prolate ellipsoids from spherical microparticles based on traveling surface acoustic wave-induced acoustic radiation force and torque.The freely rotating non-spherical microobjects were aligned under the progressive acoustic field by the counterrotating radiation torque,and the major axis of the prolate ellipsoids was parallel to the progressive wave propagation.The specific alignment of the ellipsoidal particles resulted in a reduction in the cross-sectional area perpendicular to the wave propagation.As a consequence,the acoustic backscattering decreased,resulting in a decreased magnitude of the radiation force.Through the variation in radiation force,which depended on the micro-object morphology enabled the acoustofluidic shape-based separation.We conducted numerical simulations for the wave scattering of spherical and prolate objects to elucidate the working mechanism underlying the proposed method.A series of experiments with polystyrene microspheres,prolate ellipsoids,and peanut-shaped microparticles were performed for validation.Through quantitative analysis of the separation efficiency,we confirmed the high purity and high recovery rate of the proposed acoustofluidic shapebased separation of micro-objects.As a bioparticle,we utilize Thalassiosira eccentrica to perform shape-based separation,as the species has a variety of potential applications in drug delivery,biosensing,nanofabrication,bioencapsulation and immunoisolation.

关键词： separation spherical rotating

Optimal Bidding Strategies of Microgrid with Demand Side Management for Economic Emission Dispatch Incorporating Uncertainty and Outage of Renewable Energy Sources

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Energy Engineering 2024年第4期121卷 849-867页

作者： Mousumi Basu Chitralekha Jena Baseem Khan Ahmed ali Department of Power Engineering Jadavpur UniversityJadavpurIndia School of Electrical Engineering KIIT UniversityBhubaneswarIndia Department of Electrical and Computer Engineering Hawassa UniversityHawassaEthiopia Department of Electrical and Electronic Engineering Technology Faculty of Engineering and the Built EnvironmentUniversity of JohannesburgJohannesburgSouth Africa

In the restructured electricity market,microgrid(MG),with the incorporation of smart grid technologies,distributed energy resources(DERs),a pumped-storage-hydraulic(PSH)unit,and a demand response program(DRP),is a smarter and more reliable electricity provider.DER consists of gas turbines and renewable energy sources such as photovoltaic systems and wind turbines.Better bidding strategies,prepared by MG operators,decrease the electricity cost and emissions from upstream grid and conventional and renewable energy sources(RES).But it is inefficient due to the very high sporadic characteristics of RES and the very high outage rate.To solve these issues,this study suggests non-dominated sorting genetic algorithm Ⅱ(NSGA-Ⅱ)for an optimal bidding strategy considering pumped hydroelectric energy storage and DRP based on outage conditions and uncertainties of renewable energy sources.The uncertainty related to solar and wind units is modeled using lognormal and Weibull probability distributions.TOU-based DRP is used,especially considering the time of outages along with the time of peak loads and prices,to enhance the reliability of MG and reduce costs and emissions.

关键词： Micro-grid distributed energy resources demand response program uncertainty outage

Expansion of human umbilical cord derived mesenchymal stem cells in regenerative medicine

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World Journal of Stem Cells 2024年第4期16卷 410-433页

作者： Shafiqa Naeem Rajput Bushra Kiran Naeem Anwar ali Asmat Salim Irfan Khan Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270SindhPakistan Surgical Unit 4 Dr.Ruth KM Pfau Civil HospitalKarachi 74400Pakistan Department of Physiology University of KarachiKarachi 75270Pakistan Center for Regenerative Medicine and Stem Cells Research and Department of Ophthalmology and Visual SciencesThe Aga Khan UniversityKarachi 74800SindhPakistan

BACKGROUND Stem cells are undifferentiated cells that possess the potential for self-renewal with the capacity to differentiate into multiple lineages.In humans,their limited numbers pose a challenge in fulfilling the necessary demands for the regeneration and repair of damaged tissues or organs.Studies suggested that mesenchymal stem cells(MSCs),necessary for repair and regeneration via transplantation,require doses ranging from 10 to 400 million cells.Furthermore,the limited expansion of MSCs restricts their therapeutic application.AIM To optimize a novel protocol to achieve qualitative and quantitative expansion of MSCs to reach the targeted number of cells for cellular transplantation and minimize the limitations in stem cell therapy protocols.METHODS Human umbilical cord(hUC)tissue derived MSCs were obtained and re-cultured.These cultured cells were subjected to the following evaluation pro-cedures:Immunophenotyping,immunocytochemical staining,trilineage differentiation,population doubling time and number,gene expression markers for proliferation,cell cycle progression,senescence-associatedβ-galactosidase assay,human telomerase reverse transcriptase(hTERT)expression,mycoplasma,cytomegalovirus and endotoxin detection.RESULTS Analysis of pluripotent gene markers Oct4,Sox2,and Nanog in recultured hUC-MSC revealed no significant differences.The immunophenotypic markers CD90,CD73,CD105,CD44,vimentin,CD29,Stro-1,and Lin28 were positively expressed by these recultured expanded MSCs,and were found negative for CD34,CD11b,CD19,CD45,and HLA-DR.The recultured hUC-MSC population continued to expand through passage 15.Proliferative gene expression of Pax6,BMP2,and TGFb1 showed no significant variation between recultured hUC-MSC groups.Nevertheless,a significant increase(Pality control assessments co

关键词： Human umbilical cord Mesenchymal stem cells Expansion Cell proliferation In vitro expansion Senescence

WebFLex:A Framework for Web Browsers-Based Peer-to-Peer Federated Learning Systems Using WebRTC

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Computers, Materials & Continua 2024年第3期78卷 4177-4204页

作者： Mai Alzamel Hamza ali Rizvi Najwa Altwaijry Isra Al-Turaiki Department of Computer Science College of Computer and Information SciencesKing Saud UniversityRiyadhKingdom of Saudi Arabia Department of Computer Science and Engineering Punjab Engineering CollegeChandigarhIndia

Scalability and information personal privacy are vital for training and deploying large-scale deep learning models.Federated learning trains models on exclusive information by aggregating weights from various devices and taking advantage of the device-agnostic environment of web browsers.Nevertheless,relying on a main central server for internet browser-based federated systems can prohibit scalability and interfere with the training process as a result of growing client numbers.Additionally,information relating to the training dataset can possibly be extracted from the distributed weights,potentially reducing the privacy of the local data used for training.In this research paper,we aim to investigate the challenges of scalability and data privacy to increase the efficiency of distributed training models.As a result,we propose a web-federated learning exchange(WebFLex)framework,which intends to improve the decentralization of the federated learning process.WebFLex is additionally developed to secure distributed and scalable federated learning systems that operate in web browsers across heterogeneous devices.Furthermore,WebFLex utilizes peer-to-peer interactions and secure weight exchanges utilizing browser-to-browser web real-time communication(WebRTC),efficiently preventing the need for a main central server.WebFLex has actually been measured in various setups using the MNIST dataset.Experimental results show WebFLex’s ability to improve the scalability of federated learning systems,allowing a smooth increase in the number of participating devices without central data aggregation.In addition,WebFLex can maintain a durable federated learning procedure even when faced with device disconnections and network variability.Additionally,it improves data privacy by utilizing artificial noise,which accomplishes an appropriate balance between accuracy and privacy preservation.

关键词： Federated learning web browser privacy deep learning

Exploring the shadow of a rotating charged ModMax black hole

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Communications in Theoretical Physics 2024年第2期76卷 89-101页

作者： Khurshid Karshiboev Farruh Atamurotov Ahmadjon Abdujabbarov ali Övgün Anvar Reyimberganov Institute of Theoretical Physics National University of UzbekistanTashkent 100174Uzbekistan New Uzbekistan University Movarounnahr Street 1Tashkent 100000Uzbekistan Central Asian University Milliy Bog'Street 264Tashkent 111221Uzbekistan University of Tashkent for Applied Sciences Str.Gavhar 1Tashkent 100149Uzbekistan Tashkent State Technical University Tashkent 100095Uzbekistan Ulugh Beg Astronomical Institute Astronomy Street 33Tashkent 100052Uzbekistan Institute of Fundamental and Applied Research National Research University TIIAMEKori Niyoziy 39Tashkent 100000Uzbekistan Physics Department Eastern Mediterranean UniversityFamagusta99628 North Cyprusvia Mersin 10Turkey Urgench State University Urgench 220100Uzbekistan

The research presented in this paper discusses the impact that the parameters of charge(Q)and screening factor(γ)have on properties of the horizon and silhouette of rotating charged Mod Max black holes which were reviewed in[Eur.Phys.J.C(2022)82:1155]recently,building upon previous findings in the field.Furthermore,the study explores the behavior of null geodesics,which can help us better understand the apparent shape of the black hole’s silhouette,as well as the distortion parameter and approximate radii of the silhouette that are influenced by the aforementioned parameters,and there are some values of parameter Q which corresponds to data from the Event Horizon Telescope(EHT).Notably,we explore the distortion parameter and approximate radii of the silhouette,revealing that while an increase inγleads to a growth in silhouette radius(Rs),it simultaneously reduces the distortion rate(δs).Conversely,heightened Q charge results in a reduction of Rsaccompanied by an increase inδs.Lastly,the paper analyzes the effects of the black hole’s parameters on the effective potential and energy emission:the peak value of the energy emission rate experiences a decrease as the screening factor(γ)increases,while it increases with higher values of the charge parameter(Q).

关键词： black hole ModMax gravity rotating black hole black hole shadow

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