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Modelling of debris-flow susceptibility and propagation: a case study from Northwest Himalaya

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Journal of Mountain Science 2024年第1期21卷 200-217页

作者： Hamza DAUD Javed iqbal TANOLI Sardar Muhammad asif Muhammad QASIM Muhammad ALI Junaid KHAN Zahid Imran BHATTI Ishtiaq Ahmad Khan JADOON Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China Department of Earth Sciences COMSATS University IslamabadAbbottabad Campus 22010Pakistan Department of Earth Sciences Sultan Qaboos UniversityAl-KhoudMascat 123Oman Faculty of Engineering China University of Geosciences(Wuhan)Wuhan 430074China Department of Earth Sciences Abbottabad University of Science and TechnologyHavelian 22500Pakistan

The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study area which is extending along Karakorum Highway(KKH) from Besham to Chilas. Intense seismicity, deep gorges, steep terrain and extreme climatic events trigger multiple mountain hazards along the KKH, among which debris flow is recognized as the most destructive geohazard. This study aims to prepare a field-based debris flow inventory map at a regional scale along a 200 km stretch from Besham to Chilas. A total of 117 debris flows were identified in the field, and subsequently, a point-based debris-flow inventory and catchment delineation were performed through Arc GIS analysis. Regional scale debris flow susceptibility and propagation maps were prepared using Weighted Overlay Method(WOM) and Flow-R technique sequentially. Predisposing factors include slope, slope aspect, elevation, Topographic Roughness Index(TRI), Topographic Wetness Index(TWI), stream buffer, distance to faults, lithology rainfall, curvature, and collapsed material layer. The dataset was randomly divided into training data(75%) and validation data(25%). Results were validated through the Receiver Operator Characteristics(ROC) curve. Results show that Area Under the Curve(AUC) using WOM model is 79.2%. Flow-R propagation of debris flow shows that the 13.15%, 22.94%, and 63.91% areas are very high, high, and low susceptible to debris flow respectively. The propagation predicated by Flow-R validates the naturally occurring debris flow propagation as observed in the field surveys. The output of this research will provide valuable input to the decision makers for the site selection, designing of the prevention system, and for the protection of current infrastructure.

关键词： North Pakistan Debris flow Flow-R Propagation Susceptibility mapping Debris-flow inventory Weighted Overlay Method

Quintessence anisotropic stellar models in quadratic and Born-Infeld modified teleparallel Rastall gravity

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Chinese Physics B 2024年第3期33卷 179-189页

作者： Allah Ditta 夏铁成 Irfan Mahmood asif Mahmood Department of Mathematics Shanghai University and Newtouch Center for Mathematics of Shanghai UniversityShanghai 200444China Centre for High Energy Physics University of the PunjabLahorePakistan College of Engineering Chemical Engineering DepartmentKing Saud University RiyadhSaudi Arabia

This study aims to discuss anisotropic solutions that are spherically symmetric in the quintessence field,which describe compact stellar objects in the modified Rastall teleparallel theory of gravity.To achieve this goal,the Krori and Barua arrangement for spherically symmetric components of the line element is incorporated.We explore the field equations by selecting appropriate off-diagonal tetrad fields.Born-Infeld function of torsion f(T)=β√λT+1-1 and power law form h(T)=δTn are used.The Born-Infeld gravity was the first modified teleparallel gravity to discuss inflation.We use the linear equation of state pr=ξρto separate the quintessence density.After obtaining the field equations,we investigate different physical parameters that demonstrate the stability and physical acceptability of the stellar models.We use observational data,such as the mass and radius of the compact star candidates PSRJ 1416-2230,Cen X-3,&4U 1820-30,to ensure the physical plausibility of our findings.

关键词： anisotropic spheres quintessence field modified Rastall teleparallel gravity equation of state(EoS) f(T)gravity

Phonon Thermal Transport at Interfaces of a Graphene/Vertically Aligned Carbon Nanotubes/Hexagonal Boron Nitride Sandwiched Heterostructure

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Chinese Physics Letters 2024年第1期41卷 57-62页

作者：李檬璘 Muhammad asif Shakoori 王瑞鹏李海鹏 School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China

Molecular dynamics simulation is used to calculate the interfacial thermal resistance of a graphene/carbon nanotubes/hexagonal boron nitride(Gr/CNTs/hBN)sandwiched heterostructure,in which vertically aligned carbon nanotube(VACNT)arrays are covalently bonded to graphene and hexagonal boron nitride layers.We find that the interfacial thermal resistance(ITR)of the Gr/VACNT/hBN sandwiched heterostructure is one to two orders of magnitude smaller than the ITR of a Gr/hBN van der Waals heterostructure with the same plane size.It is observed that covalent bonding effectively enhances the phonon coupling between Gr and hBN layers,resulting in an increase in the overlap factor of phonon density of states between Gr and hBN,thus reducing the ITR of Gr and hBN.In addition,the chirality,size(diameter and length),and packing density of sandwich-layer VACNTs have an important influence on the ITR of the heterostructure.Under the same CNT diameter and length,the ITR of the sandwiched heterostructure with armchair-shaped VACNTs is higher than that of the sandwiched heterostructure with zigzag-shaped VACNTs due to the different chemical bonding of chiral CNTs with Gr and hBN.When the armchair-shaped CNT diameter increases or the length decreases,the ITR of the sandwiched heterostructure tends to decrease.Moreover,the increase in the VACNT packing density also leads to a continuous decrease in the ITR of the sandwiched heterostructure,attributed to the extremely high intrinsic thermal conductivity of CNTs and the increase of out-of-plane heat transfer channels.This work may be helpful for understanding the mechanism for ITR in multilayer vertical heterostructures,and provides theoretical guidance for a new strategy to regulate the interlayer thermal resistance of heterostructures by optimizing the design of sandwich layer thermal interface materials.

关键词： sandwich shaped packing

Tricuspid mass-curious case of Li-Fraumeni syndrome: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1936-1939页

作者： Tyler Huffaker Stella Pak Anum asif Prince Otchere Department of Cardiology University of Texas Health San AntonioSan AntonioTX 78701United States Department of Neurology Albany Medical CenterAlbanyNY 12208United States

BACKGROUND Li-Fraumeni syndrome(LFS)is a rare autosomal dominant cancer-predisposing syndrome,which can manifest as a polymorphic spectrum of malignancies.LFS is associated with an early onset in life,with the majority of cases occurring prior to the age of 46.Notwithstanding the infrequency of primary cardiac tumors,it behooves clinicians to remain vigilant in considering the differential diagnosis of such tumors in LFS patients who present with a cardiac mass.This is due to the markedly elevated risk for malignancy in this particular population,far surpassing that of the general populace.CASE SUMMARY Herein,we present a case of a 30-year-old female with LFS who was found to have a tricuspid valve leaflet mass.CONCLUSION This case exemplifies valuable learning points in the diagnostic approach for this exceptionally rare patient population.

关键词： Li-Fraumeni syndrome Cardiac mass Intracardiac thrombus Transesophageal echocardiogram Cardiac magnetic resonance imaging Case report

Synthesis and Thermal Characterization of Solar Salt-Based Phase Change Composites with Graphene Nanoplatelets

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Journal of Thermal Science 2024年第2期33卷 491-500页

作者： Pethurajan VIGNESHWARAN Saboor SHAIK Sivan SURESH Müslüm ARICI asif AFZAL Department of Thermal and Energy Engineering School of Mechanical Engineering(SMEC)Vellore Institute of TechnologyVelloreTamil NaduIndia Nanotechnology Research Laboratory Department of Mechanical EngineeringNational Institute of TechnologyTiruchirappalliTamil NaduIndia Mechanical Engineering Department Engineering FacultyKocaeli UniversityUmuttepe CampusKocaeli41001Turkey Department of Mechanical Engineering P.A.College of Engineering(affiliated to Visvesvaraya Technological UniversityBelagavi)Mangaluru574153India

Thermal energy storage(TES) systems use solar energy despite its irregular availability and day-night temperature difference.Current work reports the thermal characterizations of solar salt-based phase change composites in the presence of graphene nanoplatelets(GNP).Solar salt(60:40 of NaNO_(3):KNO_(3)) possessing phase transition temperature and melting enthalpy of 221.01℃ and 134.58 kJ/kg is proposed as a phase change material(PCM) for high-temperature solar-based energy storage applications.Thermal conductivity must be improved to make them suitable for widespread applications and to close the gap between the system needs where they are employed.GNP is added at weight concentrations of 0.1%,0.3%,and 0.5% with solar salt using the ball milling method to boost its thermal conductivity.Morphological studies indicated the formation of a uniform surface of GNP on solar salt.FTIR spectrum peaks identified the physical interaction between salt and GNP.Thermal characterization of the composites,such as thermal conductivity,DSC and TGA was carried out for the samples earlier and later 300 thermal cycles.0.5% of GNP has improved the thermal conductivity of salt by 129.67% and after thermal cycling,the enhancement reduced to 125.21% indicating that thermal cycling has a minor impact on thermal conductivity.Phase change temperature decreased by around 2.32% in the presence of0.5% GNP and the latent heat reduced by 4.34% after thermal cycling.TGA thermograms depicted the composites initiated the weight loss at around 550℃ after which it was rapid.After thermal cycling,the weight loss initiated at ~40℃ lower compared to pure salt,which was found to be a minor change.Thermal characterization of solar salt and GNP-based solar salt composites revealed that the composites can be used for enhanced heat transfer in high-temperature solar-based heat transfer and energy storage applications.

关键词： thermal energy storage high temperature solar salt graphene nanoplatelets thermal characterization

Application of Ceramic Film as Means of Lubrication for Forming of TiSheet in a Highly Localized Deformation Process

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Journal of Wuhan University of Technology(Materials Science) 2014年第5期29卷 1023-1027页

作者： GHULAM Hussain asif iqbal Department of Mechanical Engineering Eastern Mediterranean UniversityG. Magusa N. Cyprus Turkey Department of Mechanical and Aerospace Engineering Air UniversityIslamabad Pakistan

Incremental forming is a novel die-less sheet forming process. There is a need for special means to retain lubricant at the tool/sheet interface during forming. To fulfillthe stated aim, a porous ceramic film was developed on pure Ti substrate, and it was done through an electrochemical depsition process known as plasma electrolytic oxidation. The film with preferred pore size could be realized after several attempts by varying the processing parameters. In order to characterize the film, a variety of tests including rnicrostructure, film-substrate bond strength and tribological properties tests were conducted. On-job performance of the film was also examined by forming Ti components employing a range of forming conditions. It was found that the proposed method of lubrication was effective, and the plasma eletrolytic oxidation process can be employed to fabricate films on pure Ti sheet to provide means of lubrication during incremental forming.

关键词： surface film characterization plasma electrolytic oxidation incremental forming pure titanium

Core-shell design of UiO66-Fe_(3)O_(4) configured with EDTA-assisted washing for rapid adsorption and simple recovery of heavy metal pollutants from soil

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Journal of Environmental Sciences 2024年第5期139卷 556-568页

作者： Xi Wang asif Hussain Qingqing Li Mingyu Ma Juan Wu Mingqiang Deng Jie Yang Dengxin Li Department of Environmental Science and Engineering Donghua UniversityShanghai 201620China Department of Environmental Science Federal Urdu University of ArtsScience and Technology75300 KarachiPakistan Shanghai Academy of Environmental Sciences Shanghai 200233China

The coupling of washing with adsorption process can be adopted for the treatment of soils contaminated with heavy metals pollution.However,the complex environment of soil and the competitive behavior of leaching chemicals considerably restrain adsorption capacity of adsorbent material during washing process,which demands a higher resistance of the adsorbents to interference.In this study,we synthesized strongly magnetic,high specific surface area(573.49 m^(2)/g)UiO66 composites(i.e.,UiO66-Fe_(3)O_(4))using hydrothermal process.The UiO66-Fe_(3)O_(4) was applied as an adsorbent during the ethylene diamine tetraacetic acid(EDTA)-assisted washing process of contaminated soil.The incorporation of UiO66-Fe_(3)O_(4)results in rapid heavy metal removal and recovery from the soil under low concentrations of washing agent(0.001 mol/L)with reduced residual heavy metal mobility of soil after remediation.Furthermore,UiO66-Fe_(3)O_(4)can quickly recollect by an external magnet,which offers a simple and inexpensive recovery method for heavy metals from contaminated soil.Overall,UiO66-Fe_(3)O_(4)configuration with EDTA-assisted washing process showed opportunities for heavy metals contaminated sites.

关键词： UiO66 composites Metal-EDTA complexes EDTA-assisted washing Heavy metals recovery Soil

Treatment of uveitis and scleritis patients in Malaysia

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 518-527页

作者： Sieng Teng Seow iqbal Tajunisah Fei Yee Lee Pooi Wah Lott Sagili Chandrasekhara Reddy Department of Ophthalmology University Malaya Eye Research Centre(UMERC)Faculty of MedicineUniversiti MalayaKuala Lumpur 59100Malaysia Clinical Research Centre Selayang HospitalMinistry of Health MalaysiaSelangor 68100Malaysia Department of Ophthalmology Faculty of Medicine and Defence HealthNational Defence University of MalaysiaKuala Lumpur 57000Malaysia

●AIM:To determine the common causes and visual outcome after treatment among uveitis and scleritis patients.●METHODS:This is a retrospective cohort observational study.All consecutive clinical records of patients with newly diagnosed uveitis and scleritis over a 4-year period,from Jan.1,2017 to Dec.31,2020,were analysed.Data was collected at the presentation and included a follow-up period of one year.●RESULTS:A total of 288 patients were recruited during the study period.Anterior uveitis was the most common anatomical diagnosis(50.0%)followed by panuveitis(25.0%),scleritis(13.5%),posterior uveitis(6.9%),and intermediate uveitis(4.5%).Viral Herpes was the most common cause of infectious cases,while Vogt-Koyanagi-Harada(VKH)disease and human leucocyte antigen(HLA)B27 spondyloarthropathy were the leading causes of identifiable non-infectious cases.Majority of patients presented with unilateral,non-granulomatous uveitis with an absence of hypopyon.Anatomical locations like posterior uveitis and panuveitis,and visual acuity worse than 3/60 at presentation were the factors associated with poor visual outcomes(P<0.05).About 60%of patients had an identifiable cause for the uveitis and scleritis,with nearly equal distribution of infectious(n=85,29.5%)and noninfectious causes(n=84,29.2%).About 14.5%of patients were clinically blind at 1y of follow-up.The most common complication in our uveitis patients was glaucoma(47.5%),followed by cystoid macula oedema(18.9%)and cataract(13.9%).●CONCLUSION:Uveitis and scleritis are important causes of ocular morbidity.They are potentially blinding diseases which can have a good outcome if diagnosed and treated early.

关键词： uveitis scleritis ocular morbidity blindness aetiology

Weber Law Based Approach for Multi-Class Image Forgery Detection

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Computers, Materials & Continua 2024年第1期78卷 145-166页

作者： Arslan Akram Javed Rashid Arfan Jaffar Fahima Hajjej Waseem iqbal Nadeem Sarwar Department of Computer Science Superior UniversityLahore54000Pakistan Information Technology Services University of OkaraOkara56300Pakistan Departmet of Computer Science MLC LabOkara56300Pakistan Department of CS&SE International Islamic UniversityIslamabad44000Pakistan Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Software Engineering Superior UniversityLahore54000Pakistan Department of Computer Science Bahria UniversityLahore CampusLahore54600Pakistan

Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain an illegitimate benefit or createmisleading publicity by using tempered images.Exiting forgery detectionmethods can classify only one of the most widely used Copy-Move and splicing forgeries.However,an image can contain one or more types of forgeries.This study has proposed a hybridmethod for classifying Copy-Move and splicing images using texture information of images in the spatial domain.Firstly,images are divided into equal blocks to get scale-invariant features.Weber law has been used for getting texture features,and finally,XGBOOST is used to classify both Copy-Move and splicing forgery.The proposed method classified three types of forgeries,i.e.,splicing,Copy-Move,and healthy.Benchmarked(CASIA 2.0,MICCF200)and RCMFD datasets are used for training and testing.On average,the proposed method achieved 97.3% accuracy on benchmarked datasets and 98.3% on RCMFD datasets by applying 10-fold cross-validation,which is far better than existing methods.

关键词： Copy-Move and splicing non-overlapping block division texture features weber law spatial domain xgboost