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Assessment of Tree Diversity and Abundance in Rashad Natural Reserved Forest, South Kordofan, Sudan

Open Journal of Forestry 2021年第1期11卷 37-46页

作者： Khalid A E Eisawi Hong He tayyab shaheen Emad H. E. Yasin College of Forestry Northwest A & F University Yangling China College of Forest & Range University of East Kordofan Rashad South Kordofan Sudan College of Forestry Key Laboratory of National Forestry and Grassland Administration on Management of Forest Bio-Disaster Northwest A & F University Yangling China Faculty of Forestry University of Khartoum Khartoum North Postal Code Sudan

This study aims to estimate the tree diversity status of Rashad Forest Reserves in the Rashad locality of the South Kordofan State of Sudan. For data collection, eight sample plots (20 × 20 m) were taken randomly, and parameters were determined: trees species diversity, composition, relative density, dominance, important value index, and species richness in the Rashad forest reserve. The results show that a total of 237 and 56 tree species, including 22 families, have been identified in the study area. Fabaceae family and species numbers have the highest number of 13 species in 8 genera, followed by Combretaceae with 8 species belonging to 3 different genera, Malvaceae with 5 species belonging to 4 different genera, Apocynaceae with 3 species belonging to 3 different genera. The Arecaceae, Burseraceae, Capparaceae, Euphorbiaceae, Meliaceae, and Rubiaceae families each had two species, and all the other 11 families had one species each. Among the 56 different tree species found within the reserve. The results also indicated that Tamarindus indica L. and Ziziphus spina-christi (L.) Desf. had the highest relative density and dominance of 4.64% and 11% respectively. Adansonia digitata L

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Anisotropic extensions of isotropic Finch–Skea metric in the charged modified gravity

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Communications in Theoretical Physics 2024年第9期76卷 118-140页

作者： tayyab Naseer M Sharif Department of Mathematics and Statistics The University of Lahore1-Km Defence RoadLahore 54000Pakistan

In this study,we explore the Finch–Skea perfect fluid solution and extend its domain to three distinct anisotropic interior models within the framework of the f(R,T)theory,incorporating the influence of an electromagnetic *** assume a static spherical spacetime initially coupled with an isotropic matter *** then introduce a Lagrangian corresponding to an additional gravitating source,taking into account its role in inducing pressure anisotropy within the original fluid *** deriving the field equations for the combined matter setup,we applied a radial component transformation,which yielded two distinct systems of *** addition,we consider a charged exterior spacetime to determine the three constants associated with the Finch–Skea solution at the *** findings suggest that under certain parametric choices,all three resulting models exhibited physical relevance within this modified theory.

关键词： anisotropy modified gravity gravitational decoupling

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Highly Active Interfacial Sites in SFT-SnO_(2) Heterojunction Electrolyte for Enhanced Fuel Cell Performance via Engineered Energy Bands:Envisioned Theoretically and Experimentally

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Energy & Environmental Materials 2024年第3期7卷 384-397页

作者： Sajid Rauf Muhammad Bilal Hanif Faiz Wali Zuhra tayyab Bin Zhu Naveed Mushtaq Yatao Yang Kashif Khan Peter D.Lund Martin Motola Wei Xu College of Electronic and Information Engineering and State Key Laboratory of Radio frequency Heterogeneous Integration Shenzhen UniversityShenzhen 518000China Department of Inorganic Chemistry Faculty of Natural SciencesComenius University in BratislavaIlkovicova 684215BratislavaSlovakia College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China School of Energy and Environment Southeast UniversityNo.2 Si Pai LouNanjing 210096China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China New Energy Technologies Group Department of Applied PhysicsAalto University School of ScienceP.O.Box 15100Fl-00076AaltoEspoo Finland

Extending the ionic conductivity is the pre-requisite of electrolytes in fuel cell technology for high-electrochemical *** this regard,the introduction of semiconductor-oxide materials and the approach of heterostructure formation by modulating energy bands to enhance ionic conduction acting as an electrolyte in fuel ***(n-type;SnO_(2))plays a key role by introducing into p-type SrFe_(0.2)Ti_(0.8)O_(3-δ)(SFT)semiconductor perovskite materials to construct p-n heterojunction for high ionic ***,two different composites of SFT and SnO_(2)are constructed by gluing p-and n-type SFT-SnO_(2),where the optimal composition of SFT-SnO_(2)(6∶4)heterostructure electrolyte-based fuel cell achieved excellent ionic conductivity 0.24 S cm^(-1)with power-output of 1004 mW cm^(-2)and high OCV 1.12 V at a low operational temperature of 500℃.The high power-output and significant ionic conductivity with durable operation of 54 h are accredited to SFT-SnO_(2)heterojunction formation including interfacial conduction assisted by a built-in electric field in fuel cell ***,the fuel conversion efficiency and considerable Faradaic efficiency reveal the compatibility of SFT-SnO_(2)heterostructure electrolyte and ruled-out short-circuiting ***,the first principle calculation provides sufficient information on structure optimization and energy-band structure modulation of SFT-SnO_(2).This strategy will provide new insight into semiconductor-based fuel cell technology to design novel electrolytes.

关键词： high ionic conductivity interfacial conduction modulated energy band structure p-n heterojunction semiconductors

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Assessment of Tree Diversity and Abundance in Rashad Natural Reserved Forest, South Kordofan, Sudan

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Open Journal of Forestry（林学期刊） 2021年第1期

作者： Khalid A E Eisawi Hong He tayyab shaheen Emad H. E. Yasin

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Barley chitinase genes expression revamp resistance against whitefly (Bemisia Tabaci) in transgenic cotton (Gossypium hirsutum L.)

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Journal of Cotton Research 2024年第1期7卷 90-100页

作者： BASHIR Samina YAQOOB Amina BASHIR Rohina BUKHARI Shanila SHAHID Naila AZAM Saira BAKHSH Allah HUSNAIN tayyab SHAHID Ahmad Ali RAO Abdul Qayyum Centre of Excellence in Molecular Biology University of the PunjabLahore 53700Pakistan Department of Botany Kinnaird College for Women UniversityLahore 54000Pakistan Department of Botany Government College UniversityFaisalabad 38000Pakistan Institute of Botany University of the PunjabLahore 54590Pakistan.

Background Chitinase is an enzyme that hydrolyzes chitin,a major component of the exoskeleton of insects,including plant pests like *** present study aimed to investigate the expression of chemically synthesized barley ch1 and chi2 genes in cotton(Gossypium hirsutum)through Agrobacterium-mediated ***-five putative transgenic cotton plants were obtained,out of which fifteen plants successfully survived and were shifted to the *** gene-specific primers,amplification of 447 bp and 401 bp fragments confirmed the presence of the ch1 and chi2 genes in five transgenic cotton plants of the T0 *** five plants were further evalu-ated for their mRNA expression *** T0 transgenic cotton plants with the highest mRNA expression level and better yield performance in field,were selected to raise their subsequent *** The T1 cotton plants showed the highest mRNA expression levels of 3.5-fold in P10(2)for the ch1 gene and 3.7-fold in P2(1)for the chi2 *** in situ hybridization(FISH)confirmed a single copy number of ch1 and chi2(hemizygous)on chromosome ***,the efficacy of transgenes on whitefly was evaluated through an insect bioassay,where after 96 h of infestation,mortality rates of whitefly were calculated to be 78%–80%in transgenic cotton *** number of eggs on transgenic cotton plants were calculated to be 0.1%–0.12 per plant compared with the non-transgenic plants where egg number was calculated to be 0.90–1.00 per *** Based on these findings,it can be concluded that the chemically synthesized barley chitinase genes(ch1 and chi2)have the potential to be effective against insects with chitin exoskeletons,including *** transgenic cotton plants expressing these genes showed increased resistance to whiteflies,resulting in reduced egg numbers and higher mortality rates.

关键词： Chitinase Cotton White fly Transgene Bioassay

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Risk factors and outcomes of peptic ulcer bleed in a Pakistani population:A single-center observational study

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2024年第3期15卷 1-9页

作者： Nazish Butt Muhammad tayyab Usmani Nimrah Mehak Saba Mughal Fakhar Ali Qazi-Arisar Ghulam Mohiuddin Gulzar Khan Department of Gastroenterology Jinnah Postgraduate Medical CentreKarachi 75505SindhPakistan National Institute of Liver&GI Diseases Dow University of Health SciencesKarachi 75330SindhPakistan School of Public Health Dow University of Health SciencesKarachi 75330SindhPakistan

BACKGROUND Peptic ulcer disease(PUD)remains a significant healthcare burden,contributing to morbidity and mortality *** advancements in therapies,its prevalence persists,particularly in regions with widespread nonsteroidal antiinflammatory drugs(NSAIDs)use and Helicobacter pylori *** To comprehensively analyse the risk factors and outcomes of PUD-related upper gastrointestinal(GI)bleeding in Pakistani *** This retrospective cohort study included 142 patients with peptic ulcer bleeding who underwent upper GI endoscopy from January to December *** on demographics,symptoms,length of stay,mortality,re-bleed,and Forrest classification was *** The mean age of patients was 53 years,and the majority was men(68.3%).Hematemesis(82.4%)and epigastric pain(75.4%)were the most common presenting *** patients(73.2%)were discharged within five *** mortality rates at one week and one month were 10.6%and 14.8%,***-bleed within 24 h and seven days occurred in 14.1%and 18.3%of patients,*** ulcers were Forrest class(FC)Ⅲ(72.5%).Antiplatelet use was associated with higher mortality at 7 and 30 d,while alternative medications were linked to higher 24-hour re-bleed *** use was associated with more FCⅢ***-bleed at 24 h and 7 d was strongly associated with one-week or one-month *** Antiplatelet use and rebleeding increase the risk of early mortality in PUD-related upper GI bleeding,while alternative medicines are associated with early rebleeding.

关键词： Non variceal bleed Mortality Re-bleed Forrest classification Antiplatelets Alternative medicines

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Economic and Social Impact Assessment of Chronic Diseases Among the Low-Income Population in Southern Punjab,Pakistan

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Proceedings of Anticancer Research 2024年第4期8卷 67-74页

作者： Mehran Khan Muhammad Arbab Nasir Muhammad Umar Asadullah Faiz Mirza Muhammad Abdul Bari Ayesha Saeed Fiza Nazeer Khan Saliha Mehboob Malik Akashah Usama tayyab Bahawalpur College of Pharmacy BMDC Complex63100BahawalpurPunjabPakistan

Introduction:Chronic diseases are becoming more prevalent *** effects of chronic illnesses are disastrous not only for the diagnosed person but also for their entire *** study explores chronic diseases’social and economic impact on low-income *** study aims to determine the economic and social implications of various chronic diseases and the loss of income due to these conditions among low-income individuals in Southern Punjab,***:A sample of 424 patients was selected from different areas of Southern *** were collected using a questionnaire that included questions about economic status,self-reported health status,social status,management strategies,and health insurance,among other ***:The mean monthly income of the respondents was found to be 57,097.6 Pakistani rupee(PKR),and the mean monthly expenses for treatment were 8,256.1 *** loss of income was calculated at 15%.Additionally,62%of patients spent more than 10%of their monthly income on managing their *** 85%of the respondents reported that chronic diseases affected their social ***,80%of patients lacked health ***:Chronic diseases impose significant economic and social burdens on patients and their families in Southern *** reduce the burden of chronic diseases,the government should enhance healthcare services in this region and provide health insurance to low-income families.

关键词： Chronic diseases Low-income families Economic impact Punjab Pakistan

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Polarization multiplexing based duplex radio-over-fiber link for millimeter wave signal transmission to a ring of multiple radio access units

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 300-306页

作者： tayyab MEHMOOD Hina QAYYUM Salman GHAFOOR School of Electrical Engineering and Computer Science National University of Sciences and Technology

A radio-over-fiber(RoF) distributed antenna system(DAS) architecture is proposed, where millimeter wave(mm-wave) signals are transmitted to four different radio access units(RAUs) arranged in a ring *** proposed architecture transmits duplex data of 128 Mb/s to each RAU in both downlink(DL) and uplink(UL)directions. The radio frequency(RF) signals are transmitted by polarization multiplexing a multi-wavelength ***-wave signals at a frequency of 25 GHz are generated at each RAU using remote heterodyne *** proposed architecture provides increased coverage while maintaining good bit error rate(BER) results.

关键词： Radio over fiber Millimeter wave Radio access units

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Trajectory tracking control of a VTOL unmanned aerial vehicle using offset-free tracking MPC

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Chinese Journal of Aeronautics 2020年第7期33卷 2024-2042页

作者： tayyab MANZOOR Yuanqing XIA Di-Hua ZHAI Dailiang MA School of Automation Beijing Institute of TechnologyBeijing 100081China

Designing a stable and robust flight control system for an Unmanned Aerial Vehicle(UAV)is an arduous *** paper addresses the trajectory tracking control problem of a Ducted Fan UAV(DFUAV)using offset-free Model Predictive Control(MPC)technique in the presence of various uncertainties and external *** designed strategy aims to ensure adequate flight robustness and stability while overcoming the effects of time delays,parametric uncertainties,and *** six degrees of freedom DFUAV model is divided into three flight modes based on its airspeed,namely the hover,transition,and cruise *** Dryden wind turbulence is applied to the DFUAV in the linear and angular velocity ***,different uncertainties such as parametric,time delays in state and input,are introduced in translational and rotational *** the previous work,the Linear Quadratic Tracker with Integrator(LQTI)is used for comparison to corroborate the performance of the designed *** are computed to investigate the control performance for the aforementioned modes and different flight phases including the autonomous flight to validate the performance of the designed ***,discussions are provided to demonstrate the effectiveness of the given methodology.

关键词： Autonomous flight control Model Predictive Control(MPC) Time delays Trajectory tracking Unmanned Aerial Vehicle(UAV)

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A novel method for locating the source of sustained oscillation in power system using synchrophasors data

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Protection and Control of Modern Power Systems 2020年第1期5卷 340-351页

作者： Mohd Zuhaib Mohd Rihan Mohd tayyab Saeed Electrical Engineering Department Zakir Husain College of Engineering and TechnologyAligarh Muslim University(AMU)AligarhIndia Al-Mostajed Technologies Pvt Ltd DubaiUAE

Large interconnected power systems are usually subjected to natural oscillation(NO)and forced oscillation(FO).NO occurs due to system transient response and is characterized by several oscillation modes,while FO occurs due to external perturbations driving generation *** to NO,FO is considered a more severe threat to the safe and reliable operation of power ***,it is important to locate the source of FO so corrective actions can be taken to ensure stable power system *** this paper,a novel approach based on two-step signal processing is proposed to characterize FO in terms of its frequency components,duration,nature,and the location of the *** recorded by the Phasor Measurement Units(PMUs)in a Wide Area Monitoring System(WAMS)is utilized for *** PMU data usually contains white noise and appears as multi-frequency oscillatory signal,the first step is to de-noise the raw PMU data by decomposing it into a series of intrinsic mode functions(IMF)using Improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(ICEEMDAN)*** most appropriate IMF containing the vital information is selected using the correlation *** second step involves various signal processing and statistical analysis tools such as segmented Power Spectrum Density(PSD),excess kurtosis,cross PSD *** achieve the desired *** analysis performed on the simulated two-area four-machine system,reduced WECC-179 bus 29 machine system,and the real-time power system PMU data set from ISO New England,demonstrates the accuracy of the proposed *** proposed approach is independent of complex network topologies and their characteristics,and is also robust against measurement noise usually contained in PMU data.

关键词： Forced oscillation(FO) Natural oscillation(NO) Phasor measurement unit(PMU) Wide area monitoring system(WAMS) Empirical mode decomposition(EMD)etc

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