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61篇 您的检索式:作者名="Muhammad UMAIR"
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1滇南喀斯特地区灌木群落和人工林土壤元素化学计量特征显示文摘在云南喀斯特地区,为提升退化灌木群落的生态系统服务功能,营造了不同树种的人工林分。这些人工林分如何影响土壤化学性质还未得到充分认识。以云南泸西县灌木群落及三种常见人工林(云南松(Pinus yunnanensis)、赤杨(Alnus japonica)和侧柏(Platycladus orientalis))土壤为研究对象探讨喀斯特地区在人工林建造后土壤的13种元素全量、可利用性含量和化学计量学特征变异格局,为喀斯特石漠化治理提供理论依据。结果表明,1)基于判别分析,四种群落土壤化学计量特征可以显著区分。土壤Fe、P、K、Mn全量及交换性Ca、交换性Mg和NH4^+-N对区分四种群落土壤贡献最大。2)四种群落之间相比,侧柏林土壤C、N、S、Na全量和NO3^--N含量均低于其他三种群落,土壤肥力较低;赤杨林铵态氮含量最高;云南松林有效Fe、有效Cu含量最高。而且,四个群落土壤全量C/N、C/K比值存在显著差异性。3)根据四种群落13种土壤元素和pH值相关性分析,35对元素具有显著相关性,占所有元素对数的38.5%,说明该地土壤元素积累的相互依赖性。与灌木群落相比,人工林土壤元素全量和可利用性含量相关性比例均更高。这些研究结果对今后基于适地适树人工林营造、生态系统服务功能提升和经营利用,均具有重要指导意义。陶慧敏 孙宁骁 温家豪 Umair Muhammad 袁俊 杜红梅 刘春江 2019生态学报2019,39,24:8
2NS1 antigen: A new beam of light in the early diagnosis of dengue infection显示文摘Objective: To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection. Methods: The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELISA and its comparison with viral RNA detection via real time PCR and Ig M antibodies detection by ELISA. Results: A total of 1 270 serum samples were tested 86%(1 097/1 270) were detected positive by one or more than one diagnostic test. Out of 1 270, 64%(807/1 270) were positive by NS1 ELISA and 52%(662/1 270), 51%(646/1 270) were positive by real-time RT-PCR and Ig M ELISA respectively.Conclusions: NS1 antigen detection ELISA is highly suitable diagnostic tools and it also has great value for use in outbreak and epidemic situation.Muhammad Suleman Rani Faryal Muhammad Masroor Alam Salmaan Sharif Shahzad Shaukat Uzma Bashir Aamir Adnan Khurshid Mehar Angez Massab Umair Mian Muhammad Sufian Yasir Arshad Ghulam Mujtaba Syed Sohail Zahoor Zaidi 2016Asian Pacific Journal of Tropical Medicine2016,9,12:6
3Design and Optimization of Segmented PM Consequent Pole Hybrid Excited Flux Switching Machine for EV/HEV Application显示文摘Hybrid Excited Flux Switching Machines(HEFSMs)unique feature of high torque density(T_(den))of Permanent Magnet(PM)machines and flux regulation capability of wound field excitation machines.Due to aforesaid unique features,stator active HEFSMs are preferred for EV/HEV applications.In this paper a new Segmented PM Consequent Pole HE-FSM(SPMCPHEFSM)with flux bridge is proposed for EV/HEV.The developed SPMCPHEFSM exhibits improved flux modulation and flux regulation capability at reduced PM usage(suppressed PM volume by 46.52%and PM cost by 46.48%)and eliminating stator leakage flux.First,SPMCPHEFSM is geometric optimized(GO)for investigating influence of leading design with key performance indicators such as flux linkage(Ф_(pp)),average torque(T_(avg)),cogging torque(T_(cog)),T_(den),average power(P_(avg))and power density(P_(den))and then proceeded optimized model to structure modification for optimal stator design and position of field excitation coils(FEC).Comprehensive performance analysis reveals that the developed SPMCPHEFSM show improvedФ_(pp)maximum up to 9.11%,improved T_(avg)maximum up to 23.63%,truncate T_(cog)up to 18.9%whereas T_(den)and P_(den)are boost up to 23.55%and 89.72%respectively.Wasiq Ullah Faisal Khan Muhammad Umair 2020CES Transactions on Electrical Machines and Systems2020,4,3:6
4滇南喀斯特地区不同季节土壤和灌木叶片化学计量特征及对水分添加的响应显示文摘干旱是影响南方喀斯特地区植物生长的重要限制因子,气候变化会影响该地区的降水量和分布格局。研究该地区土壤和植物化学计量特征及其水分响应格局,具有重要意义。自2017年4月开始,在云南建水喀斯特植物群落进行加水试验,2018年4月(旱季)和8月(雨季)分别采集土壤和优势灌木鞍叶羊蹄甲(Bauhinia brachycarpa)和假虎刺(Carissa spinarum)叶片样品,测定碳、氢、氮、磷、硫、钾、钙、镁、铝、钠、铁、锰、锌、铜14种元素含量。结果表明,水分添加影响了表层土壤中碳、氮、钠的含量,相比于旱季,雨季土壤中钠和硫含量明显减少,其余土壤元素在水分添加和季节变化下并未表现出明显差异。土壤水分含量的增加使得鞍叶羊蹄甲和假虎刺叶片中钾含量下降,钙含量上升。在水分条件变化下,两种植物叶元素含量的稳定性与植物中元素的含量有关,含量越接近极大值(基本元素碳、氢、氮等)或极小值(微量元素铜、锌等)的元素其变异系数越小(越稳定),两种植物中含量接近于1 mg·g-1的元素磷、硫、镁的变异系数最高。在土壤水分条件变化下,假虎刺中碳、氮、磷等大量元素含量的稳定性显著高于鞍叶羊蹄甲。降水变化和水分添加导致的土壤水分变化,对滇南喀斯特地区土壤和植物中不同元素含量的影响不同,这些结果将为该地区的土壤、植被修复和管理提供科学参考。敬洪霞 孙宁骁 Muhammad UMAIR 刘春江 杜红梅 2020植物生态学报2020,44,1:5
5Multi-Objective Optimization of High Torque Density Segmented PM Consequent Pole Flux Switching Machine with Flux Bridge显示文摘Due to double salient structure,Flux Switching Machines(FSMs)are preferred for brushless AC high speed applications.Permanent Magnet(PM)FSMs(PM-FSMs)are suited applicants where high torque density(Tden)and power density(Pden)are the utmost requisite.However conventional PM-FSMs utilizes excessive rare earth PM volume VPM,higher cogging torque Tcog,high torque ripples(Trip)and comparatively lower(Tden)and Pden due to flux leakage.To overcome the aforesaid demerits,a new high(Tden)Segmented PM Consequent Pole(CP)FSM(SPMCPFSM)with flux bridge and barrier is proposed which successfully reduces VPM by 46.52%and PM cost by 46.48%.Moreover,Multi-Objective Optimization(MOO)examines electromagnetic performance due to variation in geometric parameters for global optimum parameters with key metric such as flux linkage(Φpp),flux harmonics(ΦTHD)average torque(Tavg),Tcog,Trip,Tden,average power(Pavg)and Pden.Analysis reveals that MOO improveΦpp by 22.68%,boost Tavg by 11.41%,enhanced Pavg by 4.55%and increased Tden and Pden by 11.41%.Detailed electromagnetic performance comparison with existing state of the art shows that proposed SPMCPFSM offer Tavg maximum up to 88.8%,truncate Trip up to 24.8%,suppress Tcog up to 22.74%,and results 2.45 times Tden and Pden.Wasiq Ullah Faisal Khan Muhammad Umair 2021CES Transactions on Electrical Machines and Systems2021,5,1:4
6Sugar beet yield and industrial sugar contents improved by potassium fertilization under scarce and adequate moisture conditions显示文摘Sugar beet(Beta vulgaris L.) is an industrial crop, grown worldwide for sugar production. In Pakistan, sugar is mostly extracted from sugarcane, soil and environmental conditions are equally favorable for sugar beet cultivation. Beet sugar contents are higher than sugarcane sugar contents, which can be further increased by potassium(K) fertilization. Total K concentration is higher in Pakistani soils developed from mica minerals, but it does not represent plant available K for sustainable plant growth. A pot experiment was conducted in the wire-house of Institute of Soil and Environmental Sciences at University of Agriculture Faisalabad, Pakistan. K treatments were the following: no K(K_0), K application at 148 kg ha^(–1)(K_1) and 296 kg ha^(–1)(K_2). Irrigation levels were used as water sufficient at 60% water holding capacity and water deficient at 40% water holding capacity. The growth, yield and beet quality data were analyzed statistically using LSD. The results revealed that increase in the level of K fertilization at water sufficient level significantly increased plant growth, beet yield and industrial beet sugar content. The response of K fertilization under water deficient condition was also similar, however overall sugar production was less than that in water sufficient conditions. It is concluded from this study that K application could be used not only to enhance plant growth and beet yield but also enhance beet sugar content both under water-deficient as well as water-sufficient conditions.Muhammad Umair Mubarak Muhammad Zahir Sagheer Ahmad Abdul Wakeel 2016Journal of Integrative Agriculture2016,15,11:4
7Phyto-Toxicity of Chromium in Maize: Oxidative Damage, Osmolyte Accumulation, Anti-Oxidative Defense and Chromium Uptake显示文摘Agricultural production systems are immensely exposed to different environmental stresses in which heavy metal stress receives serious concerns. This study was conducted to explore the deleterious effects of different chromium(Cr) stress levels, i.e., 0, 30, 6090, 120, and 150 μmol L-1, on two maize genotypes, Wandan 13 and Runnong 35. Both genotypes were evaluated by measuring their growth and yield characteristics, Cr accumulation in different plant tissues, alterations in osmolyte accumulation, generation o reactive oxygen species(ROS), and anti-oxidative enzyme activity to scavenge ROS. The results showed that Cr stress decreased the leaf area, cob formation, 100-grain weight, shoot fresh biomass, and yield formation, while Cr accumulation in different maize tissues was found in the order of roots > leaves > stem > seeds in both genotypes. The increased Cr toxicity resulted in higher free proline soluble sugars and total phenolic contents, and lower soluble protein contents. However, enhanced lipid peroxidation was noticed in the forms of malondialdehyde, hydrogen peroxide(H2O2) and thiobarbituric acid reactive substance accumulation, and electrolyte leakage. The hyperactivity of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, especially glutathione peroxidase and glutathione reductase indicated that these anti-oxidative enzymes had a central role in protecting maize from Cr toxicity, especially for Wandan 13. Moreover, higher uptake and less translocation of Cr contents into the grains of Wandan 13 implied its importance as a potential candidate against soil Cr pollution.Shakeel Ahmad ANJUM Umair ASHRAF Imran KHAN Mohsin TANVEER Muhammad SHAHID Abdul SHAKOOR WANG Longchang 2017Pedosphere2017,27,2:3
8Torque Characteristics of High Torque Density Partitioned PM Consequent Pole Flux Switching Machines With Flux Barriers显示文摘Unique double salient structure of Permanent Magnet Flux Switching Machines(PMFSM)with both Concentrated Armature inding(CAW)and Permanent Magnet(PM)on stator attract researcher's interest for high speed brushless application when high torque density(T den)and power density(P den)are the primal requirements.However,despite of stator leakage flux,high rare-earth PM usage,PMFSM is subjected to slot effects due to presence of both PM and CAW in stator and partial saturation due to double salient structure which generates cogging torque(T cog),torque ripples(Trip)and lower average torque(T avg).To overcomne aforesaid demerits,this paper presents Partitioned PM(PPM)Consequent Pole Flux Switching Machine(PPM-CPFSM)with flux barriers to enhance flux mnodulation,curtail PM usage and diminish stator leakage flux which reduces slotting effects and partial saturation to ultimately reduces T cog and Trip In comparison with the existing state of the art,proposed PPM-CPFSM reduces 46.5390 of the total PM volumne and offer Tavg higher up to 88.8%,suppress Trip naximun up to 24.8%,diminish Tcog up to 22.74%and offer 2.45 times Tden and Pden.Furthermore,torque characteristics of proposed PPM-CPFSM is investigated utilizing space harmonics injection i.e.inverse cosine,inverse cosine with 3rd harmonics and rotor pole shaping techniques i.e.,ecce ntric circle,chanfering and notching.Detailed electromagnetic perfornance analysis reveals that harmonics injection suppressed Tcog maximun up to 83.5%,Trip up to 40.72%at the cost of 4.71%Tavg.Finally,rotor mnechanical stress analysis is utilized for rotor withstand capability and 3D-FEA based Coupled Elctromagnetic Thermal Analysis(CETA)for thermal behavior of the developed PPM CPFSM.CETA reveals that open space along PPM act as cooling duct that inprove heat dissipation.Wasiq Ullah Faisal Khan Erwan Sulaiman Muhammad Umair 2020CES Transactions on Electrical Machines and Systems2020,4,2:3
9The Impact of Internet of Things Supported by Emerging 5G in Power Systems: A Review显示文摘The Internet of Things(IoT)is playing an important role in providing access to affordable,clean and green energy worldwide through the use of smart devices.The current electric power networks will be more reliable,secure,flexible and durable by implementing IoT in power systems.This paper presents a brief discussion about IoT contributions in the development of power systems from a generation,transmission,distribution and consumption point of view.5G cellular networks have a great potential for the development of IoT technology.Additionally,5G cellular networks can be instrumental in supporting the greater communication needs of IoT.This review provides a comprehensive analysis about the role of 5G cellular networks in the growth of IoT technology and power systems.Large amounts of data will be generated due to the incorporation of renewable energy,deployment of the smart grid and the improvements to the electricity market.In this way,in order to realize the connection between things and people,things and things and people and people in power systems,it is essential to apply IoT in power systems.In this case,5G is providing numerous advantages to Power IoT(PIoT)by offering greater opportunities in progress and improvements;however,there are also numerous challenges with the deployment of 5G in PIoT.Finally,this review article provides an overview of the role,implications and challenges of 5G in PIoT.Jinsong Tao Muhammad Umair Muhammad Ali Jian Zhou 2020CSEE Journal of Power and Energy Systems2020,6,2:3
10Wolbachia pipientis:A potential candidate for combating and eradicating dengue epidemics in Pakistan显示文摘Dengue virus syndrome is an emerging global health challenge which is endemic in tropical countries like Pakistan.In recent years dengue incidences have increased considerably in different areas of Pakistan with more sever impacts on urban and peri-urban populations.This review is an effort to highlight the changing epidemiology of dengue fever,role of Government of Pakistan in disease management and control using preventive and community based approaches in the region.Moreover,there is an emphasis on application of Wolbachia as novel,inexpeasive and environmentally benign candidate for control and eradication of dengue transmitting vectors.Uruj Tahir Umair Hassan Khan Muhammad Saad Zubair Bahar-e-Mustafa 2015Asian Pacific Journal of Tropical Medicine2015,8,12:2
11Alleviating the crosstalk effect via a fine-moulded light-blocking matrix for colour-converted micro-LED display with a 122% NTSC gamut显示文摘One of the major challenges when fabricating high gamut colour-converted micro-light-emitting diodes(LEDs)displays is severe crosstalk effect among adjacent pixels because of the wide view-angle feature of micro-LED chips.In this study,potential factors that contribute to the crosstalk effect were systematically simulated.We observed that precisely filling the space between each micro-LED chip with a light blocking matrix(LBM)can be a promising solution to alleviate this risk.After careful investigations,a press-assisted moulding technique was demonstrated to be an effective approach of fabricating the LBM.Nevertheless,experimental observations further revealed that residual black LBM on the surface of micro-LEDs severely reduces the brightness,thereby compromising the display performance.This problem was successfully addressed by employing a plasma etching technique to efficiently extract the trapped light.Eventually,a top-emitting blue micro-LED-based backlight fine-moulded with a black LBM was developed and combined with red and green quantum dot colour-conversion layers for full-colour display.The colour gamut of our manufactured display prototype can cover as high as 122%that of the National Television Standards Committee.Yongming Yin Zhiping Hu Muhammad Umair Ali Miao Duan Yongwei Wu Ming Liu Wenxiang Peng Jun Hou Dongze Li Xin Zhang Hong Meng 2022Light(Advanced Manufacturing)2022,3,3:2
12Morphometry of leaf and shoot variables to assess aboveground biomass structure and carbon sequestration by different varieties of white mulberry(Morus alba L.)显示文摘Mulberry is economically important and can also play a pivotal role in mitigating greenhouse gases.Leaf and shoot traits were measured for Morus alba var.Kanmasi,M.alba var.Karyansuban,M.alba var.Latifolia,and M.alba var.PFI-1 to assess aboveground biomass(AGB)and carbon sequestration.Variety-specific and multivariety allometric AGB models were developed using the equivalent diameter at breast height(EDBH)and plant height(H).The completeharvest method was used to measure leaf and shoot traits and biomass,and the ash method was used to measure organic carbon content.The results showed significant(p<0.01)varietal differences in leaf and shoot traits,AGB and carbon sequestration.PFI-1 variety had the greatest leaf density(mean±SE:1828.3±0.3 leaves tree^(-1)),Karyansuban had the largest mean leaf area(185.94±8.95 cm^(2)).A diminishing return was found between leaf area and leaf density.Latifolia had the highest shoot density per tree(46.6±1.83 shoots tree^(-1)),total shoot length(264.1±2.32 m),dry biomass(16.69±0.58 kg tree^(-1)),carbon sequestration(9.99±0.32 kg tree^(-1))and CO_(2) mitigation(36.67±1.16 kg).The variety-specific AGB models b(EDBH)and b(EDBH)2 showed good fit and reasonable accuracy with a coefficient of determination(R^(2))=0.98-0.99,standard error of estimates(SEE)=0.1125-0.3130 and root mean square error(RMSE)=0.1084-0.3017.The multivariety models bln(EDBH)and(EDBH)0.756 showed good-fitness and accuracy with R^(2)=0.85-0.86,SEE=1.6231-1.6445 and RMSE=1.609-1.630.On the basis of these findings,variety Latifolia has good potential for biomass production,and allometric equations based on EDBH can be used to estimate AGB with a reasonable accuracy.Ghulam Ali Bajwa Muhammad Umair Yasir Nawab Zahid Rizwan 2021Journal of Forestry Research2021,32,6:2
13Optimal Rotor Poles and Structure for Design of Consequent Pole Permanent Magnet Flux Switching Machine显示文摘Permanent magnet flux switching machines(PMFSM)have attracted significant research interest and are considered as competent candidates when higher torque density is primary requirement.However,conventional PMFSMs uses excessive rare earth PM volumes which ultimately increases machine the machine weight and PM cost.Moreover,the PMs extended at the stator yoke results in stator leakage flux which degrades the performance.To suppress the leakage flux and diminish the PM volume,the consequent pole PMFSM(CPPMFSM)with flux bridges and barriers encompassing partitioned circumferential and radial magnetized PMs is proposed,thereby ensuring an alternate magnetic path for the working harmonics which improves the modulation effect and flux distribution.Moreover,the influence of the rotor pole number on seven different rotor structures namely,curved rotor,trapezoidal rotor,wide rotor tooth tip,wide rotor base width,rectangular segmented and eccentric rotors are investigated based on the electromagnetic performance and stress distribution.Finite element analysis(FEA)reveals that the 12S-13P CPPMFSM with a wider rotor base offers comparatively better electromagnetic performance.Compare to the conventional PMFSM,the proposed CPPMFSM reduces the PM volume which minimizes the overall machine cost and weight,suppresses the torque ripples by 16.49%,diminishes total harmonic distortion(THD)by 35.24%and decreases cogging torque by 32.88%.Furthermore,the torque and power density are enhanced by 7.028%and 7.025%respectively.Wasiq Ullah Faisal Khan Muhammad Umair 2021Chinese Journal of Electrical Engineering2021,7,1:2
14An Efficient Internet Traffic Classification System Using Deep Learning for IoT显示文摘Internet of Things(IoT)defines a network of devices connected to the internet and sharing a massive amount of data between each other and a central location.These IoT devices are connected to a network therefore prone to attacks.Various management tasks and network operations such as security,intrusion detection,Quality-of-Service provisioning,performance monitoring,resource provisioning,and traffic engineering require traffic classification.Due to the ineffectiveness of traditional classification schemes,such as port-based and payload-based methods,researchers proposed machine learning-based traffic classification systems based on shallow neural networks.Furthermore,machine learning-based models incline to misclassify internet traffic due to improper feature selection.In this research,an efficient multilayer deep learning based classification system is presented to overcome these challenges that can classify internet traffic.To examine the performance of the proposed technique,Moore-dataset is used for training the classifier.The proposed scheme takes the pre-processed data and extracts the flow features using a deep neural network(DNN).In particular,the maximum entropy classifier is used to classify the internet traffic.The experimental results show that the proposed hybrid deep learning algorithm is effective and achieved high accuracy for internet traffic classification,i.e.,99.23%.Furthermore,the proposed algorithm achieved the highest accuracy compared to the support vector machine(SVM)based classification technique and k-nearest neighbours(KNNs)based classification technique.Muhammad Basit Umair Zeshan Iqbal Muhammad Bilal Jamel Nebhen Tarik Adnan Almohamad Raja Majid Mehmood 2022Computers, Materials & Continua2022,,4:1
15Viséan Fossil Plants from the Jiujialu Formation in Central Guizhou Province: Implications for Age of Bauxite and Palaeoenvironment显示文摘Fossil plants from the carbonaceous shale of upper part of the Lower Carboniferous Jiujialu Formation in Lindai bauxite deposit fill a gap regarding the distribution of Early Carboniferous flora in Central Guizhou Province.Here the Lindai plant assemblage is systematically described,and its composition and geological age are discussed.Research demonstrates that 9 species in 6 genera of the fossil plants are discovered in this study,and they belong to lycopsids,sphenopsids and ferns,respectively.Based on the analysis of the floral composition,the geological age of the Lindai plant assemblage belongs to the Early Carboniferous Viséan.The discovery of Lindai plant assemblage not only provides a new fossil evidence to restrict the age of bauxite deposits in Lower Carboniferous Jiujialu Formation of Central Guizhou Province,but also has great significance to further research the palaeoecological setting and floral evolution during the Early Carboniferous.LUO Chaokun YANG Ruidong GAO Junbo Muhammad UMAIR WANG Longbo GAO Lei 2020Acta Geologica Sinica(English Edition)2020,94,6:1
16Multi-material Bio-inspired Soft Octopus Robot for Underwater Synchronous Swimming显示文摘Inspired by the simple yet amazing morphology of the Octopus, we propose the design, fabrication, and characterization of multi-material bio-inspired soft Octopus robot (Octobot). 3D printed molds for tentacles and head were used. The tentacles of the Octobot were casted using Ecoflex-0030 while head was fabricated using relatively flexible material, i.e., OOMOO-25. The head is attached to the functionally responsive tentacles (each tentacle is of 79.12 mm length and 7 void space diameter), whereas Shape Memory Alloy (SMA) muscle wires of 0.5 mm thickness are used in Octobot tentacles for dual thrust generation and actuation of Octobot. The tentacles were separated in two groups and were synchronously actuated. Each tentacle of the developed Octobot contains a pair of SMA muscles (SMA-α and SMA-β). SMA-α muscles being the main actuator, was powered by 9 V, 350 mA power supply, whereas SMA-β was used to provide back thrust and thus helps to increase the actuation frequency. Simulation work of the proposed model was performed in the SolidWorks environment to verify the vertical velocity using the octopus tentacle actuation. The design morphology of Octobot was optimized using simulation and TRACKER software by analyzing the experimental data of angle, displacement, and velocity of real octopus. The as-developed Octobot can swim at variable frequencies (0.5–2 Hz) with the average speed of 25 mm/s (0.5 BLS). Therefore, the proposed soft Octopus robot showed an excellent capability of mimicking the gait pattern of its natural counterpart.Faheem Ahmed Muhammad Waqas Bushra Shaikh Umair Khan Afaque Manzoor Soomro Suresh Kumar Hina Ashraf Fida Hussain Memon Kyung Hyun Choi 2022Journal of Bionic Engineering2022,19,5:1
17Tactile and temperature sensors based on organic transistors:Towards e-skin fabrication显示文摘Tactile and temperature sensors are the key components for e-skin fabrication.Organic transistors,a kind of intrinsic logic devices with diverse internal configurations,offer a wide range of options for sensor design and have played a vital role in the fabrication of e-skin-oriented tactile and temperature sensors.This research field has attained tremendous advancements,both in terms of materials design and device architecture,thereby leading to excellent performance of resulting tactile/temperature sensors.Herein,a systematic review of organic transistor-based tactile and temperature sensors is presented to summarize the latest progress in these devices.Particularly,we focus on spotlighting various device structures,underlying mechanisms and their performance.Lastly,an outlook for the future development of these devices is briefly discussed.We anticipate that this review will provide a quick overview of such a rapidly emerging research direction and attract more dedicated efforts for the development of next-generation sensing devices towards e-skin fabrication.Miao Zhu Muhammad Umair Ali Changwei Zou Wei Xie Songquan Li Hong Meng 2021Frontiers of physics2021,16,1:1
18Concentration-Dependent Solar Thermochemical CO_(2)/H_(2)O Splitting Performance by Vanadia-Ceria Multiphase Metal Oxide Systems显示文摘The effects of V and Ce concentrations(each varying in the 0-100%range)in vanadia-ceria multiphase systems are investigated for synthesis gas production via thermochemical redox cycles of CO_(2) and H_(2)O splitting coupled to methane partial oxidation reactions.The oxidation of prepared oxygen carriers is performed by separate and sequential CO_(2) and H_(2)O splitting reactions.Structural and chemical analyses of the mixed-metal oxides revealed important information about the Ce and V interactions affecting their crystal phases and redox characteristics.Pure CeO_(2) and pure V_(2)O_(5) are found to offer the lowest and highest oxygen exchange capacities and syngas production performance,respectively.The mixed-oxide systems provide a balanced performance:their oxygen exchange capacity is up to 5 times higher than that of pure CeO_(2) while decreasing the extent of methane cracking.The addition of 25%V to CeO_(2) results in an optimum mixture of CeO_(2) and CeVO4 for enhanced CO_(2) and H_(2)O splitting.At higher V concentrations,cyclic carbide formation and oxidation result in a syngas yield higher than that for pure CeO_(2).Asim Riaz Muhammad Umair Ali T.Gabriel Enge Takuya Tsuzuki Adrian Lowe Wojciech Lipinski 2020Research2020,,1:1
19Digestive system involvement and clinical outcomes among COVID-19 patients:A retrospective cohort study from Qatar显示文摘BACKGROUND Coronavirus disease 2019(COVID-19)caused by the severe acute respiratory syndrome coronavirus 2 virus most commonly presents with respiratory symptoms.While gastrointestinal(GI)manifestations either at presentation or during hospitalization are also common,their impact on clinical outcomes is controversial.Some studies have described worse outcomes in COVID-19 patients with GI symptoms,while others have shown either no association or a protective effect.There is a need for consistent standards to describe GI symptoms in COVID-19 patients and to assess their effect on clinical outcomes,including mortality and disease severity.AIM To investigate the prevalence of GI symptoms in hospitalized COVID-19 patients and their correlation with disease severity and clinical outcomes.METHODS We retrospectively reviewed 601 consecutive adult COVID-19 patients requiring hospitalization between May 1-15,2020.GI symptoms were recorded at admission and during hospitalization.Demographic,clinical,laboratory,and treatment data were retrieved.Clinical outcomes included all-cause mortality,disease severity at presentation,need for intensive care unit(ICU)admission,development of acute respiratory distress syndrome,and need for mechanical ventilation.Multivariate logistic regression model was used to identify independent predictors of the adverse outcomes.RESULTS The prevalence of any GI symptom at admission was 27.1%and during hospitalization was 19.8%.The most common symptoms were nausea(98 patients),diarrhea(76 patients),vomiting(73 patients),and epigastric pain or discomfort(69 patients).There was no difference in the mortality between the two groups(6.21%vs 5.5%,P=0.7).Patients with GI symptoms were more likely to have severe disease at presentation(33.13%vs 22.5%,P<0.001)and prolonged hospital stay(15 d vs 14 d,P=0.04).There was no difference in other clinical outcomes,including ICU admission,development of acute respiratory distress syndrome,or need for mechanical ventilation.Drugs associated with the development of GI symptoms during hospitalization were ribavirin(diarrhea 26.37%P<0.001,anorexia 17.58%,P=0.02),hydroxychloroquine(vomiting 28.52%,P=0.009)and lopinavir/ritonavir(nausea 32.65%P=0.049,vomiting 31.47%P=0.004,and epigastric pain 12.65%P=0.048).In the multivariate regression analysis,age>65 years was associated with increased mortality risk[odds ratio(OR)7.53,confidence interval(CI):3.09-18.29,P<0.001],ICU admission(OR:1.79,CI:1.13-2.83,P=0.012),and need for mechanical ventilation(OR:1.89,CI:1.94-2.99,P=0.007).Hypertension was an independent risk factor for ICU admission(OR:1.82,CI:1.17-2.84,P=0.008)and need for mechanical ventilation(OR:1.66,CI:1.05-2.62,P=0.028).CONCLUSION Patients with GI symptoms are more likely to have severe disease at presentation;however,mortality and disease progression is not different between the two groups.Muhammad Umair Khan Kamran Mushtaq Deema Hussam Alsoub Phool Iqbal Fateen Ata Hammad Shabir Chaudhry Fatima Iqbal Girisha Balaraju Muna A Al Maslamani Betsy Varughese Rajvir Singh Khalid Al Ejji Saad Al Kaabi Yasser Medhat Kamel Adeel Ajwad Butt 2021World Journal of Gastroenterology2021,27,46:1
20Automation of irrigation system using ANN based controller显示文摘MUHAMMAD UMAIR S LSMAN R 2009International Journal of Electrical & Computer Sciences2009,10,2:1
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