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A two step facile synthesis of new steroidal linear and angular pyranones having anti-mycobacterial activity

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Chinese Chemical Letters 2009年第2期20卷 153-157页

作者： Shams-uz-zaman Tabassum Siddiqui Mohd.Gulfam Alam Najmul Islam Department of Chemistry(Steroid Lab) Aligarh Muslim University Department of Biochemistry Faculty of medicineJ.N.Medical College

Title compounds 2′,2′-dimethylcholesta-2,4-dien[3,2-b]-pyran-4′-one （3）, 2′,2′-dimethyl-3β-substituted cholesta-4,6-dien[7,6- b]-pyran-4′-one （6a,b） and （6c） were prepared by the cyclization of 2-acetylcholesta-2,4-dien-3-ol （2）, 6-acetyl-3β-substituted- cholesta-4,6-dien-7-ol （Sa,b） and （5c） respectively, with pyrrolidine, dry benzene and dry acetone using Dean Stark separator through conventional heating. Furthermore, compounds were also found to be active against Mycobacterium tuberculosis.

关键词： Steroidal linear and angular pyranones Acetyl hydroxy derivative of steroids Pyrrolidine Acetyl chloride Dean Stark separator Anti-mycobacterial activity

Low-power, high-speed, and area-efficient sequential circuits by quantum-dot cellular automata: T-latch and counter study

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Frontiers of Information Technology & Electronic Engineering 2023年第3期24卷 457-469页

作者： Mohammad GHOLAMI zaman AMIRZADEH Department of Electrical Engineering Faculty of Engineering and TechnologyUniversity of MazandaranBabolsar ***Iran Department of Electrical Engineering Mazandaran University of Science and TechnologyBabol ***Iran

Quantum-dot cellular automata(QCA)is a new nanotechnology for the implementation of nano-sized digital *** nanotechnology is remarkable in terms of speed,area,and power consumption compared to complementary metal-oxide-semiconductor(CMOS)technology and can significantly improve the design of various logic *** propose a new method for implementing a T-latch in QCA technology in this *** proposed method uses the intrinsic features of QCA in timing and clock phases,and therefore,the proposed cell structure is less occupied and less power-consuming than existing implementation *** the proposed T-latch,compared to previous best designs,reductions of 6.45%in area occupation and 44.49%in power consumption were *** addition,for the first time,a reset-based T-latch and a T-latch with set and reset capabilities are *** the proposed T-latch,a new 3-bit counter is developed which reduces 2.14%cell numbers compared to the best of previous ***,based on the 3-bit counter,a 4-bit counter is designed,which reduces 0.51%cell numbers and 4.16%cross-section area compared to previous *** addition,two selective counters are introduced to count from 0 to 5 and from 2 to *** were performed using QCADesigner and QCAPro tools in coherence vector engine *** proposed circuits are compared with related designs in terms of delay,cell numbers,area,and leakage power.

关键词： Quantum-dot cellular automata(QCA) Quantum-dot T-latch T-flip-flop Counter Selective counter QCADesigner QCAPro

Burden and outcome of human influenza in a tertiary care hospital of Bangladesh

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Asian Pacific Journal of Tropical Medicine 2011年第6期4卷 478-481页

作者： Rasul CH Bakar MA Mamun AA Siraz MS zaman RU Department of Paediatrics Khulna Medical College & HospitalKhulnaBangladesh Department of Medicine Khulna Medical College & HospitalKhulnaBangladesh International Center for Diarrhoeal Disease Research Bangladesh

Objective:To determine the magnitude and outcome of influenza in southern part of Bangladesh and also to identify intrusion of novel influenza ***:This study was conducted for two years(2008-2009) in outpatient and inpatient department of both paediatrics and medicine discipline of Khulna Medical College *** and throat swab specimens were collected from each influenza like illness(ILI) case and kept together in a virus transport media and transported to international centre for diarrhoeal disease and research,Bangladesh laboratory. Influenza virus was detected by rRT-PCR including types and ***:A total of 526 patients were enrolled during the study period with the mean(SD) age of 19(17) years. Identification of influenza virus was 14%and positive cases were mostly found in under-five children(24%).The vast majority(88%) of influenza cases were found during April to September. Virus detection rate was higher in inpatient department(IPD)(21%) than in outpatient department (12%).The dominant virus type and subtype was influenza A(87%) and H3(49%),respectively. Type A was significantly higher than type B in causing severe illness compared to ILI(0R=7.04, 95%CI:2.76-18.7,P<0.01).Headache and chest indrawing was found in significantly higher proportion(P<0.05) in influenza positive IPD *** 31 hospitalized cases majority(77%) recovered completely except two cases that needed referral for additional ***: Influenza mostly affected under-five children and young *** peak season here was late summer and rainy season.

关键词： Influenza Burden Outcome Bangladesh

Remote Health Monitoring Using IoT-Based Smart Wireless Body Area Network

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Computers, Materials & Continua 2021年第8期68卷 2499-2513页

作者： Farhan Aadil Bilal Mehmood Najam Ul Hasan Sangsoon Lim Sadia Ejaz Noor zaman Computer Science Department COMSATS University IslamabadAttock Campus43600Pakistan Department of Electrical and Computer Engineering Dhofar UniversitySalalahOman Department of Computer Engineering Sungkyul UniversityAnyang430010Korea School of Computer Science and Engineering(SCE) Taylor’s UniversityMalaysia

A wireless body area network(WBAN)consists of tiny healthmonitoring sensors implanted in or placed on the human *** sensors are used to collect and communicate human medical and physiological data and represent a subset of the Internet of Things(IoT)*** are connected to medical servers that monitor patients’*** type of network can protect critical patients’lives due to the ability to monitor patients’health continuously and *** inter-WBAN communication provides a dynamic environment for patients allowing them to move ***,during patient movement,the WBAN patient nodes may become out of range of a remote base ***,to handle this problem,an efficient method for inter-WBAN communication is *** this study,a method using a cluster-based routing technique is *** the proposed method,a cluster head(CH)acts as a gateway between the cluster members and the external network,which helps to reduce the network’s *** clustering,the cluster’s lifetime is a vital parameter for network ***,to optimize the CH’s selection process,three evolutionary algorithms are employed,namely,the ant colony optimization(ACO),multi-objective particle swarm optimization(MOPSO),and the comprehensive learning particle swarm optimization(CLPSO).The performance of the proposed method is verified by extensive experiments by varying values of different parameters,including the transmission range,node number,node mobility,and grid size.A comprehensive comparative analysis of the three algorithms is conducted by extensive *** results show that,compared with the other methods,the proposed ACO-based method can form clusters more efficiently and increase network lifetime,thus achieving remarkable network and energy *** proposed ACO-based technique can also be used in other types of ad-hoc networks as well.

关键词： Wireless body area network clustering internet of things evolutionary algorithm ant colony optimization

Software-Defined Space-Air-Ground Integrated Network Architecture with the Multi-Layer Satellite Backbone Network

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Computers, Materials & Continua 2020年第7期64卷 527-540页

作者： Chao Guo Cheng Gong Juan Guo Zhanzhen Wei Yanyan Han Sher zaman Khan Department of Electronics and Communication Engineering Beijing Electronics Science and Technology InstituteBeijing100070China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Vocational and Technical College of Guilin University of Electronic Technology Beihai536000China Institute of Business Administration Gomal UniversityDera Ismail Khan29220Pakistan

Under the background of the rapid development of ground mobile communication,the advantages of high coverage,survivability,and flexibility of satellite communication provide air support to the construction of space information *** to the requirements of the future space information communication,a software-defined Space-Air-Ground Integrated network architecture was *** consisted of layered structure satellite backbone network,deep space communication network,the stratosphere communication network and the ground *** Space-Air-Ground Integrated network was supported by the satellite backbone *** provided data relay for the missions such as deep space exploration and controlled the deep-space spacecraft when *** addition,it safeguarded the anti-destructibility of stratospheric communication and assisted the stratosphere to supplement ground network *** this paper,algorithm requirements of the congestion control and routing of satellite backbone protocols for heterogeneous users’services were *** algorithm requirements of distinguishing different service objects for the deep space communication and stratospheric communication network protocols were *** the realistic demand for the dynamic coverage of the satellite backbone network and node cost,the multi-layer satellite backbone network architecture was *** this basis,the proposed Software-defined Space-Air-Ground Integrated network architecture could be built as a large,scalable and efficient communication network that could be integrated into space,air,and ground.

关键词： Space-Air-Ground integrated network network architecture software-defined network multi-layer satellite backbone network

Modeling the density gradient of 3D nanofiber scaffolds fabricated by divergence electrospinning

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Advances in Manufacturing 2021年第3期9卷 414-429页

作者： Muhammad Adib Uz zaman Dilshan Sooriyaarachchi Ying-Ge Zhou George Z.Tan Dong-Ping Du Department of Industrial Manufacturing and Systems EngineeringTexas Tech UniversityLubbockTXUSA

Following recent insights on structure-cell-function interactions and the critical role of the extracellular matrix(ECM),the latest biofabrication approaches have increasingly focused on designing materials with biomimetic *** electrospinning is a novel fabrication method for three-dimensional(3D)nanofiber *** is introduced to produce 3D nanofiber mats that have numerous applications in regenerative medicine and tissue *** of the most important characteristics of 3D nanofiber mats is the density *** study provides a statistical analysis and response surface modeling framework based on experimental data to evaluate the manner by which the geometric designs of double-bevel collectors influence the fiber density ***,variance of analysis and sensitivity analysis were performed to identify parameters that had significant effects,and a response surface model embedded with seven location indicators was developed to predict the spatial distribution of fiber density for different collector *** was concluded that the collector height,bevel angle,and their interactions were significant factors influencing the density *** study revealed the sensitivity of system configuration and provided an optimization tool for process controllability of microstructure gradients.

关键词： Electrospinning 3D nanofiber scaffold Statistical model Design of experiments Response surface method

Leaf and Ecosystem Gas Exchange Responses of Buffel Grass-Dominated Grassland to Summer Precipitation

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Pedosphere 2015年第1期25卷 112-123页

作者： Mir zaman HUSSAIN Gnaana SARASWATHI Chhakchhuak LALRAMMAWIA Dennis OTIENO Kailash PALIWAL John TENHUNEN Department of Plant Ecology University of Bayreuth Institute for Genomic Biology University of Illinois Department of Plant Sciences Madurai Kamaraj University

Sporadic rain events that occur during summer play an important role in the initiation of biological activity of semi-arid *** understand how ecosystem processes of a buffel grass(Cenchrus ciliaris L.)-dominated grassland respond to summer rain events,an LI 6 400 gas exchange system was used to measure the leaf gas exchange and plant canopy chambers were used to measure net ecosystem CO2exchange(NEE) and ecosystem respiration(Reco), which were made sequentially during periods before rain(dry) and after rain(wet). Gross ecosystem photosynthesis(GEP) was estimated from NEE and Reco fluxes, and light use efficiency parameters were estimated using a rectangular hyperbola model. Prior to the monsoon rain, grassland biomass was non-green and dry exhibiting positive NEE(carbon source) and low GEP values during which the soil water became increasingly scarce. An initial rain pulse(60 mm) increased the NEE from pre-monsoon levels to negative NEE(carbon gain) with markedly higher GEP and increased green biomass. The leaf photosynthesis and leaf stomatal conductance were also improved substantially. The maximum net CO2uptake(i.e.,negative NEE) was sustained in the subsequent period due to multiple rain events. As a result, the grassland acted as a net carbon sink for 20 d after first rain. With cessation of rain(drying cycle), net CO2 uptake was reduced to lower values. High sensitivity of this grassland to rain suggests that any decrease in precipitation in summer may likely affect the carbon sequestration of the semiarid ecosystem.

关键词： biomass CO2 exchange photosynthesis respiration soil moisture stomatal conductance

An approach for approximate solution of fractional-order smoking model with relapse class

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International Journal of Biomathematics 2018年第6期11卷 31-57页

作者： Anwar Zeb Vedat Suat Erturk Umar Khan Gul zaman Shaher Momani Department of Mathematics COMSATS University Islamabad Abbottabad Campus Pakistan Department of Mathematics Faculty of Arts and Sciences Ondokuz Mayis University 55139 Samsun Turkey Department of Mathematics University of Malakand Chakdara Dir (Lower) KPK PakistantDepartment of Mathematics Faculty of Arts and Sciences Ondokuz Mayis University 55139 Samsun Turkey Department of Mathematics Faculty of Science The University of Jordan Amman 1195 Jordan Nonlinear Analysis and Applied Mathematics (NAAM)Research Group Department of Mathematics Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia

In this paper, we develop a fractional-order smoking model by considering relapse class. First, we formulate the model and find the unique positive solution for the proposed model. Then we apply the Griinwald-Letnikov approximation in the place of maintaining a general quadrature formula approach to the Riemann-Liouville integral definition of the fractional derivative. Building on this foundation avoids the need for domain trans-formations, contour integration or involved theory to compute accurate approximate solutions of fractional-order giving up smoking model A comparative study between Griinwald-Letnikov method and Runge-Kutta method is presented in the case of integer-order derivative. Finally, we present the obtained results graphically.

关键词： Mathematical model reproductive number next generation matrix method stability analysis Griinwald-Letnikov method numerical simulation.

Flower Pollination Heuristics for Parameter Estimation of Electromagnetic Plane Waves

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Computers, Materials & Continua 2021年第8期68卷 2529-2543页

作者： Sadiq Akbar Muhammad Asif Zahoor Raja Naveed Ishtiaq Chaudhary Fawad zaman Hani Alquhayz Department of Electronics University of PeshawarPeshawar25120Pakistan Future Technology Research Center National Yunlin University of Science and TechnologyDouliou64002Taiwan Department of Electrical Engineering International Islamic UniversityIslamabad44000Pakistan Department of Electrical Engineering COMSATS University IslamabadIslamabad44000Pakistan Department of Computer Science and Information College of Science in ZulfiMajmaah UniversityAl-Majmaah11952Saudi Arabia

For the last few decades,the parameter estimation of electromagnetic plane waves i.e.,far field sources,impinging on antenna array geometries has attracted a lot of researchers due to their use in radar,sonar and under water acoustic *** this work,nature inspired heuristics based on the flower pollination algorithm(FPA)is designed for the estimation problem of amplitude and direction of arrival of far field sources impinging on uniform linear array(ULA).Using the approximation in mean squared error sense,a fitness function of the problem is developed and the strength of the FPA is utilized for optimization of the cost function representing scenarios for various number of sources non-coherent located in the far *** worth of the proposed FPA based nature inspired computing heuristic is established through assessment studies on fitness,histograms,cumulative distribution function and box plots *** other worthy perks of the proposed scheme include simplicity of concept,ease in the implementation,extendibility and wide range of applicability to solve complex optimization *** salient features make the proposed approach as an attractive alternative to be exploited for solving different parameter estimation problems arising in nonlinear systems,power signal modelling,image processing and fault diagnosis.

关键词： Direction of arrival flower pollination algorithm plane waves parameter estimation