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Chinese Journal of Chemical Engineering 2018年第9期26卷 1904-1911页

作者： Anis H.Fakeeha Ahmed S.Al-Fatesh Biswajit Chowdhury Ahmed A.Ibrahim wasim u.khan Shahid Hassan Kasim Sasudeen Ahmed Elhag Abasaeed Chemical Engineering Department College of Engineering King Saud University Department of Applied Chemistry Indian School of Mines

Methane decomposition reaction has been studied at three different activation temperatures（500℃,800℃ and950℃）over mesoporous alumina supported Ni–Fe and Mn–Fe based bimetallic *** co-impregnation of Ni on Fe/Al2O3the activity of the catalyst was retained even at the high activation temperature at 950℃ and up to180 *** Ni promotion enhanced the reducibility of Fe/Al2O3oxides showing higher catalytic activity with a hydrogen yield of 69%.The reactivity of bimetallic Mn and Fe over Al2O3catalyst decreased at 800℃ and 950℃ activation *** studies revealed that the catalyst could be effectively recycled up to *** addition of O2（1 ml,2 ml,4 ml）in the feed enhanced substantially CH4conversion,the yield of hydrogen and the stability of the catalyst.

关键词： Carbon nanotube Hydrogen production Methane decomposition Manganese promoter Nickel promoter

Catalytically active interfaces in titania nanorod-supported copper catalysts for CO oxidation

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Nano Research 2020年第2期13卷 533-542页

作者： wasim u.khan Season S.Chen Daniel C.W.Tsang Wey Yang Teoh Xijun Hu Frank L.Y.Lam Alex C.K.Yip Department of Chemical and Process Engineering The university of Canterbury Christchurch 8041New Zealand Department of Civil and Environmental Engineering.The Hong Kong Polytechnic university Hong Kong.China School of Chemical Engineering The University of New South WalesSydneyNSW 2052Australia Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyHong KongChina

One-dimensional titanium dioxide nanorod(TNR)-supported Cu catalysts(2.5 wt.%-12.5 wt.%)were synthesized using deposition-precipitation.X-ray photoelectron spectroscopy,temperature programmed reduction and CO chemisorption measurements showed that Cu doping over TNR offered metal-support interactions and interfacial active sites that had a profound impact on the catalytic *** role of the Cu-TNR interface was investigated by comparing the catalytic activity of Cu-TNR catalysts with that of pure CuO nanoparticles in CO *** presence of highly dispersed copper species,a high number of interfacial active sites,CO adsorption capacity and surface/lattice oxygen were found to be responsible for the excellent activity of 7.5Cu-TNR(ie,Cu loading of 7.5 wt.%on TNR).Moreover,the Cu-TNR catalysts followed the Langmuir-Hinshelwood reaction mechanism with 7.5Cu-TNR,exhibiting an apparent activation energy of 44.7 kJ/*** TNR-supported Cu catalyst gave the highest interfacial catalytic activity in medium-temperature CO oxidation(120-240℃)compared to other commonly used supports,including titanium dioxide nanoparticles(TiO2-P25),silica(SiO2)and alumina(Al20g)in which copper species were nonhomogeneously *** study confirms that medium-temperature CO oxidation is highly sensitive to the morphology and structure of the supporting material.

关键词： supported catalysts nanorod oxygen species interfacial active sites CO oxidation

沸石负载Ni催化剂在甲烷干重整中的稳定性(英文)

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催化学报 2013年第4期34卷 764-768页

作者： Anis H. FAKEEHA wasim u. khan Ahmed S. AL‐FATESH Ahmed E. ABASAEED Chemical Engineering Department College of Engineering King Saud University

Ni/γ-Al2O3 , Ni/Y-zeolite, and Ni/H-ZSM-5 catalysts were prepared using the incipient wetness impregnation method. Their catalytic performance in dry reforming of methane was studied. The fresh and used catalysts and deposited carbon were characterized using H2 temperature-programmed reduction, temperature-programmed oxidation, N2 adsorption-desorption, X-ray diffraction, and thermogravimetric analysis. The H-ZSM-5-supported Ni catalyst proved to be more stable than the other two catalysts, as it had the lowest carbon deposition.

关键词： Carbon dioxide Dry reforming Methane Nickel catalyst H‐ZSM‐5 zeolite Carbon deposition

Structural and Functional Analysis of NS1 and NS2 Proteins of H1N1 Subtype

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Genomics, Proteomics & Bioinformatics 2010年第3期8卷 190-199页

作者： Parveen Salahuddin Asad u.khan Distributed Information Sub-Centre Interdisciplinary Biotechnology UnitAligarh Muslim University

Influenza A virus （H1N1）, a genetic reassortment of endemic strains of human, avian and swine flu, has crossed species barrier to human and apparently acquired the capability of human to human transmission. Some strains of H5N1 subtype are highly virulent because NS 1 protein inhibits antiviral interferon α/β production. Another protein NS2 mediates export of viral ribonucleoprotein from nucleus to the cytoplasm through export signal. In this paper, we have studied structure-function relationships of these proteins of H1N1 subtype and have determined the cause of their pathogenicity. Our results showed that non-conservative mutations slightly stabilized or destabilized structural domains of NS1 or NSI-dsRNA complex, hence slightly increased or decreased the function of NS 1 protein and consequently enhanced or reduced the pathogenicity of the H1N1 virus. NS2 protein of different strains carried non-conservative mutations in different domains, resulting in slight loss of function. These mutations slightly decreased the pathogenicity of the virus. Thus, the results confirm the structure-function relationships of these viral proteins.

关键词： influenza A virus H1N1 pathogenicity NS2 NS1

Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 123-153页

作者： Muhammad Qasim khan Fazal Malik Fahad Alturise Noor Rahman Department of Computer Science Iqra National UniversityPeshawar25000Pakistan Department of Cybersecurity College of ComputerQassim UniversityBuraydah52555Saudi Arabia Department of Computer Science and Engineering Al-Fayha CollegeAl Jubayl31961Saudi Arabia

Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband ***,they consume important and scarce network resources such as bandwidth and processing *** have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial *** paper draws its motivation from such real network disaster incidents attributed to signaling *** this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and *** provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding *** important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a *** paper presents an update and an extension of our earlier conference *** our knowledge,no similar survey study exists on the subject.

关键词： Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication

Implication of 14-3-3ζ-BDNF pathway in long-lasting memory enhancement and the rescue from memory deficits

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Neural Regeneration Research 2022年第12期17卷 2685-2686页

作者： Mariam Masmudi-Martín Irene Navarro-Lobato Zafar u.khan Brain Metastasis Group National Cancer Research Centre(CNIO)MadridSpain Donders Institute for Brain Cognition and Behaviour Radboud UniversityNijmegenThe Netherlands Laboratory of Neurobiology CIMESUniversity of MalagaMalagaSpain Department of Medicine Faculty of MedicineUniversity of MalagaMalagaSpain CIBERNED Institute of Health Carlos ⅢMadridSpain

Intact memory function is critical for carrying out daily life activities,such as managing finances,remembering to take medications,driving in familiar environments,remembering a grandchild’s birthday,and learning to use a new ***,memory deficits not only accompany normal aging but are also comorbid with many psychiatric,neurological,and neurodegenerative *** disability,autism,attention deficit disorder,learning disability,schizophrenia,and depression all have memory deficit components,as do Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,and other neurodegenerative diseases(khan et al.,2014).Therefore,a large proportion of the human population is affected by this brain disorder.

关键词： Huntington remember finance

Spectrum of venous thromboembolism in adult patients with ulcerative colitis in Pakistan:A single center retrospective study

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World Journal of Clinical Cases 2025年第6期13卷 9-13页

作者： Masood Muhammad Karim Hafsa Shaikh Faisal wasim Ismail Department of Medicine The Aga Khan University HospitalKarachi 74800Pakistan Department of General Surgery The Aga Khan University HospitalKarachi 74800Pakistan

BACKGROuND Patients with inflammatory bowel disease are at a 2-8-fold higher risk of deve-loping venous thromboembolism(VTE)as compared to the general *** the exact pathogenesis is unclear,the literature suggests that increased risk of thromboembolic events in such patients occurs as a result of increased coagulation factors,inflammatory cytokines,and reduction in anticoagulants leading to a prothrombotic *** To assess the prevalence,risk factors,management,and outcome of ulcerative colitis(uC)patients who develop *** This was a retrospective chart review done in The Gastroenterology Department of The Aga khan university *** was collected from medical records for all patients admitted with a diagnosis of uC from January 2012 to December *** Seventy-four patients fulfilled the inclusion *** mean±SD of age at presentation of all uC patients was 45 years±10 years whereas for those who developed VTE,it was 47.6 years±14.7 *** and diabetes were the most common co-morbid seen among uC patients with a frequency of 17(22.9%)and 12(16.2%),respectively.A total of 5(6.7%)patients developed *** venous thrombosis was the most common thromboembolic phenomenon seen in 3(60%)*** the patients with uC and concomitant VTE were discharged home(5;100%).CONCLuSION The prevalence of VTE with uC in Pakistani patients corresponds with the international ***,multi-centric studies are required to further explore these results.

关键词： Deep venous thrombosis Inflammatory bowel disease Low-middle-income country Anticoagulation Protein C deficiency

Rising incidence of acute hepatitis A among adults and clinical characteristics in a tertiary care center of Pakistan

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World Journal of Virology 2025年第1期14卷 73-82页

作者： Yumna Shahid Amna Subhan Butt Iqra Jamali Faisal wasim Ismail Division of Gastroenterology Department of MedicineAga Khan University HospitalKarachi 74800Pakistan Department of Medicine Aga Khan University HospitalKarachi 74800Pakistan

BACKGROuND For decades,hepatitis A virus(HAV)has been a leading cause of acute hepatitis among children and was less prevalent among ***,recently a paradigm shift has been observed in the epidemiology of HAV,as evident by cases of acute hepatitis due to HAV among *** To estimate frequency of HAV in acute viral hepatitis and compare characteristics in HAV and hepatitis E virus(HEV)*** This was a trend analysis conducted at Aga khan university Hospital Karachi(Sindh,Pakistan)from February 2024 to May *** aged 18 years and older diagnosed with acute viral hepatitis attributed to hepatotropic viruses in 2024 were *** compare the trend patients admitted with acute hepatitis during 2019-2023 were also *** regarding clinical and laboratory parameters were *** yearly trend of acute hepatitis due to HAV and HEV was analyzed,and comparative analysis was done between HAV and HEV cases among *** A total of 396 patients were found to have acute hepatitis during our study *** was diagnosed in 234 patients(59%)while 157 patients(39.6%)were found to have acute HEV ***,acute hepatitis B virus infection was identified in 3 patients(0.7%),whereas acute hepatitis C virus infection was found in 2(0.5%)cases of acute *** trends showed increasing occurrence of HAV infection among adults over last 5 *** patients with acute HAV were younger than patients with HEV(28 years±8 years vs 30 years±8 years;Pubin were seen in HEV infection,while higher levels of alanine transaminase were seen in HAV ***,a higher proportion of acute liver failure(ALF),coagulopathy,and mortality were observed in *** An increase in acute hepatitis A cases among adults shows less severity than hepatitis E,highlighting the need for better sanitation,hygiene,and adult hepatitis A vaccination programs.

关键词： Acute hepatitis Hepatitis A virus Hepatitis E virus Acute liver failure Hepatotropic virus Vaccination

Adipose-derived regenerative therapies for the treatment of knee osteoarthritis

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World Journal of Stem Cells 2024年第4期16卷 324-333页

作者： Ilias E Epanomeritakis wasim S khan Division of Trauma and Orthopaedic Surgery Addenbrooke’s HospitalCambridge University Hospitals NHS Foundation TrustCambridge CB20QQUnited Kingdom Division of Trauma and Orthopaedic Surgery Department of SurgeryUniversity of CambridgeCambridge CB20QQUnited Kingdom

Knee osteoarthritis is a degenerative condition with a significant disease burden and no disease-modifying *** treatment ultimately requires joint *** capable of regenerating cartilage could significantly reduce financial and clinical *** regenerative potential of mesenchymal stromal cells(MSCs)has been extensively studied in the context of knee *** has yielded promising results in human studies,and is likely a product of immunomodulatory and chondroprotective biomolecules produced by MSCs in response to ***-derived MSCs(ASCs)are becoming increasingly popular owing to their relative ease of isolation and high proliferative *** vascular fraction(SVF)and micro-fragmented adipose tissue(MFAT)are produced by the enzymatic and mechanical disruption of adipose tissue,*** avoids expansion of isolated ASCs ex vivo and their composition of heterogeneous cell populations,including immune cells,may potentiate the reparative function of *** this editorial,we comment on a multicenter randomized trial regarding the efficacy of MFAT in treating knee *** discuss the study’s findings in the context of emerging evidence regarding adipose-derived regenerative *** underlying mechanism of action of ASCs is proposed while drawing important distinctions between the properties of isolated ASCs,SVF,and MFAT.

关键词： Knee osteoarthritis Mesenchymal stromal cells Adipose tissue Stromal vascular fraction Micro-fragmented adipose tissue Regeneration

Cognitive frequency diverse array radar with symmetric non-uniform frequency offset

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Science China(Information Sciences) 2016年第10期59卷 194-209页

作者： Abdul BASIT Ijaz Mansoor QuRESHI wasim khan Aqdas Naveed MALIK Department of Electronic Engineering International Islamic University Department of Electrical Engineering Air University Islamabad

Frequency diverse array(FDA) radar with uniform inter-element frequency offset generates a beam pattern with maxima at multiple range and angle values. Multiple maxima property allows interferers located at any of the maxima to affect the target-returns. As a result the signal to interference noise ratio(SINR) and probability of detection decreases. In this paper, we propose a cognitive uniformly-spaced FDA with non-uniform but symmetric frequency offsets to achieve a single maximum beam pattern at the target position. Moreover,these non-uniform frequency offsets are calculated using well known mu-law formulae. The design sharpens or broadens the transmitted beam pattern based on the receiver feedback to achieve a better detection probability and an improved SINR as compared to the previous designs. The performance is also analyzed by considering the Cramer-Rao lower bound(CRLB) on target angle and range estimation.

关键词： cognitive radar frequency diverse array non-uniform frequency offset range-angle beam forming