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Geochemistry and Depositional Setting of Fort Munro Formation,Middle and Lower Indus Basins,Pakistan

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Journal of China University of Geosciences 2005年第2期16卷 160-169页

作者： Shahid Naseem Shamim Ahmed sheikh Erum Bashir Khaula Shirin Department of Geology University of KarachiKarachi Pakistan Department of GeologyUniversity of KarachiKarachi Pakistan Department of GeologyUniversity of KarachiKarachi Pakistan PCSIR Lab.ComplexKarachi Pakistan

Fort Munro Formation represents the products of the Upper Cretaceous (Maastrichtian) in the middle and lower Indus basins. The formation is exposed in the Rakhi Nala (Sulaiman Range), Bara Nala (Lakhi Range) and Naka Pabni (Southern Pab Range) areas. Major and trace elemental geochemistry and petrographic studies of the formation have been carried out to understand the facies trends in the middle and lower Indus basins. A high amount of acid-insoluble fraction, Ca/Mg and Mg vs. Ca/Sr ratio reveal that the formation was deposited in a shallow marine regressive environment. High amounts of clastic reflect abundant influx of terrigenous materials from the east (Indian craton) and west (Bibai volcanic). High Sr content indicates that aragonite was the precursor mineral, which was transformed into stable low-Mg calcite during diagenesis. Enrichment of Cu and Zn contents in the samples of the formation implies the influence of volcanic activity and that they were incorporated into the calcite lattice in the late phase.

关键词： geochemistry depositional setting Fort Munro Formation middle and lower Indus basins

A Simple Method of Electrospun Tungsten Trioxide Nanofibers with Enhanced Visible-Light Photocatalytic Activity

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Nano-Micro Letters 2015年第3期7卷 291-297页

作者： Frank Agyemang Ofori Faheem A.sheikh Richard Appiah-Ntiamoah Xinsheng Yang Hern Kim Department of Energy Science and Technology Energy and Environment Fusion Technology Center Myongji University Key Laboratory of Advanced Technology of Materials Superconductor and New Energy R&D Center Southwest Jiaotong University

The present study involves the fabrication of tungsten trioxide(WO3) nanofibers by an electrospinning technique using polyvinyl pyrrolidone(PVP)/citric acid/tungstic acid as precursor solution. It was found that the PVP concentration was one of the most crucial processing parameters determining the final properties of WO3 nanofibers. The optimum concentration of PVP was from 75 to 94 g L-1. The average diameter of the nanofibers increases with increasing the PVP concentration, whereas it is decreased after sintering and orthorhombic structure were formed at 500 °C. The photocatalytic properties of the as-synthesized nanofibers were also investigated by degrading methylene blue and twofold efficiency was obtained compared with that of commercial WO3 microparticles.

关键词： Tungsten trioxide Electrospinning Nanofiber Photocatalysis

Distribution characteristics of polychlorinated biphenyls (PCBs) in coastal areas of Okinawa Island,Japan

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Chinese Journal of Oceanology and Limnology 2007年第3期25卷 247-253页

作者： M.A.sheikh F.NAKAMA T.OOMORI Marine and Environmental Science Graduate School of Engineering and Science University of the Ryukyus 1 Senbaru Nishihara-Town Okinawa 903-0213 Japan Detachment 3 Air Force Institute for Operational Health (AFIOH) Armstrong Laboratory Department of Chemistry Biology and Marine Science Faculty of Science University of the Ryukyus 1 Senbaru Nishihara-Town Okinawa 903-0213

Surface sediment and seawater samples were collected from coastal areas around Okinawa Island from September 2001 to May 2002. The samples were analyzed for total polychlorinated biphenyl (PCB) levels and homolog composition. The results show that total PCB levels ranged from 0.32 to 128.7 ng/g (dry wt.) in sediment and 1.59 to 2.48 ng/L in seawater. The levels exceed the Environmental Quality Standard (EQS) for water pollution of Japan. The distribution of PCB homolog showed different patterns in the sediments and seawaters. Penta-chlorobiphenyls (CBs) comprised the main congener group in seawater, while hexa-CBs were more abundant homologs in the sediments. The heavily contaminated sites featured higher CBs, including penta-CBs, hexa-CBs, and hepta-CBs, than those in less contaminated sites where tri-CBs dominated. This study provides current distribution and geochemical behavior of PCBs in the coastal areas around Okinawa Island.

关键词： PCBs Okinawa Island homolog coastal pollution

Exact Analysis of Non-Linear Fractionalized Jeffrey Fluid.A Novel Approach of Atangana-Baleanu Fractional Model

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Computers, Materials & Continua 2020年第12期65卷 2033-2047页

作者： Saqib Murtaza Farhad Ali Aamina Nadeem Ahmad sheikh Ilyas Khan Kottakkaran Sooppy Nisar Department of Mathematics City University of Science and Information TechnologyPeshawarKhyber PakhtnkhwaPakistan Computational Analysis Research Group Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh CityVietnam Department of Mathematics College of Science Al-ZulfiMajmah UniversityAl-Majmah11952Saudi Arabia Department of Mathematics College of Arts and SciencesPrince Sattam Bin Abdulaziz UniversityWadi AldawaserSaudi Arabia

It is a very difficult task for the researchers to find the exact solutions to mathematical problems that contain non-linear terms in the ***,this article aims to investigate the viscous dissipation(VD)effect on the fractional model of Jeffrey fluid over a heated vertical flat plate that suddenly moves in its own *** on the Atangana-Baleanu operator,the fractional model is developed from the fractional constitutive *** is responsible for the non-linear behavior in the *** taking the Laplace and Fourier sine transforms,exact expressions have been obtained for momentum and energy *** influence of relative parameters on fluid flow and temperature distribution is shown *** special cases,and for the sake of correctness,the corresponding results for second-grade fluid and Newtonian viscous fluid are also *** is interesting to note that fractional parameterαprovides more than one line as compared to the classical *** effect represents the memory effect in the fluid which is not possible to elaborate by the classical *** is also worth noting that the temperature profile of the generalized Jeffrey fluid rises for higher values of Eckert number which is due to the enthalpy difference of the boundary layer.

关键词： Viscous dissipation atangana-baleanu fractional derivative laplace transform fourier sine transform

A survey on security analysis of Amazon echo devices

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High-Confidence Computing 2022年第4期2卷 28-36页

作者： Surendra Pathak sheikh Ariful Islam Honglu Jiang Lei Xu Emmett Tomai Department of Computer Science The University of Texas Rio Grande ValleyUSA Department of Computer Science and Software Engineering Miami UniversityUSA Department of Computer Science Kent State UniversityUSA

Since its launch in 2014,Amazon Echo family of devices has seen a considerable increase in adaptation in consumer homes and *** a market worth millions of dollars,Echo is used for diverse tasks such as accessing online information,making phone calls,purchasing items,and controlling the smart *** offers user-friendly voice interaction to automate everyday tasks making it a massive *** many people view Amazon Echo as a helpful assistant at home or office,few know its underlying security and privacy *** this paper,we present the findings of our research on Amazon Echo’s security and privacy *** findings are divided into different categories by vulnerability or *** proposed mitigation(s)to the vulnerabilities are also presented in the *** conclude that though numerous privacy concerns and security vulnerabilities associated with the device are mitigated,many vulnerabilities still need to be addressed.

关键词： Amazon echo Privacy Security Intelligent virtual assistants

Garg incontinence scores: New scoring system on the horizon to evaluate fecal incontinence. Will it make a difference?

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World Journal of Gastroenterology 2024年第3期30卷 204-210页

作者： Petr Tsarkov Inna Tulina Parvez sheikh Darya D Shlyk Pankaj Garg Department of Colorectal Surgery Sechenov First Moscow State Medical UniversityMoscow 119991Russia Department of Oncologic Colorectal Surgery Sechenov First Moscow State Medical UniversityMoscow 119991Russia Department of Colorectal Surgery Saifee HospitalMumbai 400004MaharashtraIndia Department of Colorectal Surgery Garg Fistula Research InstitutePanchkula 134113HaryanaIndia

The main aim of this opinion review is to comment on the recent article published by Garg et al in the World Journal of Gastroenterology 2023;29:4593–*** authors in the published article developed a new scoring system,Garg incon-tinence scores(GIS),for fecal incontinence(FI).FI is a chronic debilitating disease that has a severe negative impact on the quality of life of the *** IV criteria define FI as multiple episodes of solid or liquid stool passed into the clothes at least twice a *** associated social stigmatization often leads to significant under-reporting of the condition,which further impairs *** important point is that the complexity and vagueness of the disease make it difficult for the patients to properly define and report the magnitude of the problem to their *** to this,the management becomes even more *** issue is resolved up to a considerable extent by a scoring *** were several scoring systems in use for the last three *** prominent of them were the Cleveland Clinic scoring system or the Wexner scoring system,*** Hospital or Vaizey’s scores,and the FI severity ***,there were several shortcomings in these scoring *** the opinion review,we tried to analyze the strength of GIS and compare it to the existing scoring *** main pitfalls in the existing scoring systems were that most of them gave equal weightage to different types of FI(solid,liquid,flatus,etc.),were not comprehensive,and took only the surgeon’s perception of FI into *** GIS,almost all shortcomings of previous scoring systems had been addressed:different weights were assigned to different types of FI by a robust statistical methodology;the scoring system was made comprehensive by including all types of FI that were previously omitted(urge,stress and mucus FI)and gave priority to patients’rather than the physicians’perceptions while developing the scoring *** to this,GIS in

关键词： Fecal incontinence Scoring system Urge Stress Flatus

Disease clearance in ulcerative colitis:A new therapeutic target for the future

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World Journal of Gastroenterology 2024年第13期30卷 1801-1809页

作者： Syed Adeel Hassan Neeraj Kapur Fahad sheikh Anam Fahad Somia Jamal Division of Digestive Disease and Nutrition University of KentuckyLexingtonKY 40536United States Department of Pathology and Laboratory Medicine Montefiore Medical CenterAlbert Einstein College of MedicineNew YorkNY 10461United States Division of Primary Care Essen HealthcareNew YorkNY 10457United States Department of Internal Medicine Karachi Medical and Dental CollegeKarachi 74700SindhPakistan

Advancements in murine modeling systems for ulcerative colitis have diversified our understanding of the pathophysiological factors involved in disease onset and *** has fueled the identification of molecular targets,resulting in a rapidly expanding therapeutic ***,management strategies have evolved from symptomatic resolution to well-defined objective endpoints,including clinical remission,endoscopic remission and mucosal *** the incorporation of these assessment modalities has permitted targeted intervention in the context of a natural disease history and the prevention of complications,studies have consistently depicted discrepancies associated with ascertaining disease status through clinical and endoscopic *** recommendations lack consideration of histological *** simultaneous achievement of clinical,endoscopic,and histologic remission has not been fully *** has laid the groundwork for a novel therapeutic outcome termed disease clearance(DC).This article summarizes the concept of DC and its current evidence.

关键词： Inflammatory bowel disease Ulcerative colitis Clinical remission Endoscopic remission Histological remission Mucosal healing Disease clearance

Biogeochemical evaluation of Nannorrhops ritchiana: A Mg-flora from Khuzdar, Balochistan, Pakistan

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Chinese Journal Of Geochemistry 2005年第4期24卷 327-337页

作者： Sadaf Naseem Shahid Naseem Erum Bashir Khaula Shirin Shamim A. sheikh Department of Geology University of Karachi Karachi 75270 PakistanDepartment of Geology University of Karachi Karachi 75270 PakistanDepartment of Geology University of Karachi Karachi 75270 PakistanPCSIR Laboratories Complex off University Road Karachi PakistanDepartment of Geology University of Karachi Karachi 75270 Pakistan

Nannorrhops ritchiana (Mazari Palm) is a distinctive flora growing in the Saharo-Sindian region. It is well distributed on the ultramafic soil, derived from the Bela Ophiolite in the Khuzdar District, Balochistan, Pakistan. Quantitative estimation of Ca, Mg, Fe and Ni in soil and plant ash has been carried out. The constituents of plant ash have been discussed in relation to soil chemistry, pH, climate, mobility, average abundance in plant ash and exclusion mechanism of the flora. Relationship among Ca, Mg, Fe and Ni has been established using scattergrams to evaluate the biogeochemistry of the plant. High contents of Mg and high coefficient of biological absorption allow it to be classed as Mg-flora. Both Ca and Fe appeared to be antagonistic to Mg. The metal assemblage of N. ritchiana nicely reflected the nature of the bed rock as being serpentinized ultramafic, and its corresponding soils. Good exclusion mechanism of N. ritchiana did not allow it to absorb high Ni from the soil. Relatively high concentrations of Ni in N. ritchiana from the Baran Lak area can be used to localize Ni-mineralization in the study area.; Statistical analyses, such as minimum, maximum, mean, mode, median, standard deviations, and coefficient of correlation, were also made to improve raw geochemical data and interpretations.

关键词：巴基斯坦生物化学超碱土壤土壤化学

Differentially private data publication with multi‐level data utility

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High-Confidence Computing 2022年第2期2卷 61-68页

作者： Honglu Jiang S.M.Sarwar Haotian Yu sheikh Ariful Islam Department of Informatics and Engineering Systems The University of Texas Rio Grande ValleyBrownsvilleUSA Department of Computer science The University of Texas Rio Grande ValleyEdinburgUSA Department of Data Analytics The George Washington UniversityWashingtonUSA

Conventional private data publication mechanisms aim to retain as much data utility as possible while ensuring sufficient privacy protection on sensitive *** data publication schemes implicitly assume that all data analysts and users have the same data access privilege ***,it is not applicable for the scenario that data users often have different levels of access to the same data,or different requirements of data *** multi-level privacy requirements for different authorization levels pose new challenges for private data *** PPDP mechanisms only publish one perturbed and private data copy satisfying some privacy guarantee to provide relatively accurate analysis *** find a good tradeoffbetween privacy preservation level and data utility itself is a hard problem,let alone achieving multi-level data utility on this *** this paper,we address this challenge in proposing a novel framework of data publication with compressive sensing supporting multi-level utility-privacy tradeoffs,which provides differential ***,we resort to compressive sensing(CS)method to project a n-dimensional vector representation of users’data to a lower m-dimensional space,and then add deliberately designed noise to satisfy differential ***,we selectively obfuscate the measurement vector under compressive sensing by adding linearly encoded noise,and provide different data reconstruction algorithms for users with different authorization *** experimental results demonstrate that ML-DPCS yields multi-level of data utility for specific users at different authorization levels.

关键词： Differential privacy Compressive sensing Multi-level utility Privacy preservation