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Synthesis and Spectral Properties of 4-（2,5-Dimethoxyphenyl- methelene）-2-phenyl-5-oxazolone （DMPO）

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Chinese Journal of Chemistry 2012年第3期30卷 563-569页

作者： EI-Daly, Samy A Asiri, Abdullah M Alamry, Khalid A Hussein, Mahmoud A Chemistry Department Faculty of Science King Abdulaziz University P.O. Box 80203 Jeddah 21589 Saudi Arabia The Center of Excellence for Advanced Materials King Abdulaziz University Jeddah 21589 P.O. Box 80203 Saudi Arabia Department of Chemistry Faculty of Science Tanta University 31527 Tanta Egypt Chemistry Department Faculty of Science Assiut University Assiut 71516 Egypt

An interesting flourophore, 4-（2,5-dimethoxyphenylmethelene）-2-phenyl-5-oxazolone （DMPO） was synthesized by mixing an equivalent molar quantity of hippuric acid and 2,5-dimethoxybenzaldehyde in acetic anhydride in the presence of anhydrous sodium acetate. The absorption and fluorescence characteristics of 4-（2,5-dimethoxy-phenyl- methelene）-2-phenyl-5-oxazolone （DMPO） were investigated in different solvents. DMPO dye exhibits red shift in both absorption and emission spectra as solvent polarity increases, indicating change in the dipole moment of mole- cules upon excitation due to an intramolecular charge transfer interaction. The fluorescence quantum yield depends strongly on the properties of the solvents, which was attributed to positive and negative solvatokinetic effects. A crystalline solid of DMPO gave strong excimer like emission at 630 nm due to the excitation of molecular aggregates. This is expected from the idealized crystal structure of the dye that belongs to the B-type class of Steven＇s Classifica- tion. DMPO displayed fluorescence quenching by triethylamine via nonemissive exciplex formation.

关键词： 4-(2,5-dimethoxy-phenylmethelene)-2-phenyl-5-oxazolone (DMPO) effect of medium fluorescencequantum yield solid state emission

Seeing Dirac electrons and heavy fermions in new boron nitride monolayers

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Chinese Physics B 2020年第5期29卷 454-458页

作者： Yu-Jiao Kang Yuan-Ping Chen Jia-Ren Yuan Xiao-Hong Yan Yue-E Xie School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China faculty of science Jiangsu UniversityZhenjiang 212013China

Most three-dimensional(3D)and two-dimensional(2D)boron nitride(BN)structures are wide-band-gap ***,we propose two BN monolayers having Dirac points and flat bands,*** monolayer is named as 5-7 BN that consists of five-and seven-membered *** other is a Kagome BN made of triangular boron rings and nitrogen *** two structures show not only good dynamic and thermodynamic stabilities but also novel electronic *** 5-7 BN has Dirac points on the Fermi level,indicating that the structure is a typical Dirac *** Kagome BN has double flat bands just below the Fermi level,and thus there are heavy fermions in the *** flat-band-induced ferromagnetism is also *** analyze the origination of the band structures by partial density of states and projection of *** addition,a possible route to experimentally grow the two structures on some suitable substrates such as the PbO2(111)surface and the CdO(111)surface is also discussed,*** research not only extends understanding on the electronic properties of BN structures,but also may expand the applications of BN materials in 2D electronic devices.

关键词： boron nitride Dirac fermion flat band ferromagnetism

Notch signaling regulates expression of Mcl-1 andapoptosis in PPD-treated macrophages

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Cellular & Molecular Immunology 2013年第5期10卷 444-452页

作者： Tanapat P alaga Siriluk Ratanabunyong Thitiporn Pattarakankul Naunpun Sangphech Wipawee Wongchana Yukihiro Hadae Patipark Kueanjinda Department of Microbiology Faculty of Science Chulalongkorn University Bangkok 10330 Thailand Interdisciplinary Program in Medical Microbiology Graduate School Chulalongkorn University Bangkok 10330 Thailand Graduate Program in Industrial Microbiology Faculty of Science Chulalongkorn University Bangkok 10330 Thailand Graduate Program in Biotechnology Faculty of Science Chulalongkorn University Bangkok 10330 Thailand International Center for Biotechnology Osaka University Osaka 565-0871 Japan

Macrophages are cellular targets for infection by bacteria and viruses. The fate of infected macrophages plays a key role in determining the outcome of the host immune response. Apoptotic cell death of macrophages is considered to be a protective host defense that eliminates pathogens and infected cells. In this study, we investigated the involvement of Notch signaling in regulating apoptosis in macrophages treated with tuberculin purified protein derivative （PPD）. Murine bone marrow-derived macrophages （BMMs） treated with PPD or infected with Mycobacterium bovis Bacillus Calmette-Guerin （BCG） induced upregulation of Notch1. This upregulation correlated well with the upregulation of the anti-apoptotic gene mcl-1 both at the transcriptional and translational levels. Decreased levels of Notch I and Mcl- 1 were observed in BMM treated with PPD when a gamma secretase inhibitor （GSI）, which inhibits the processing of Notch receptors, was used. Moreover, silencing Notch1 in the macrophage-like cell line RAW264.7 decreased Mcl-1 protein expression, suggesting that Notch1 is critical for Mcl-1 expression in macrophages. A significant increase in apoptotic cells was observed upon treatment of BMM with PPD in the presence of GSI compared to the vehicle-control treated cells. Finally, analysis of the mcl-1 promoter in humans and mice revealed a conserved potential CSURBP-Jκ binding site. The association of Notch I with the mcl-1 promoter was confirmed by chromatin immunoprecipitation. Taken together, these results indicate that Notch I inhibits apoptosis of macrophages stimulated with PPD by directly controlling the mcl-1 promoter.

关键词： apoptosis BCG macrophage Mcl-1 Notch signaling PPD

The diffusive model for West Nile virus with advection and expanding fronts in a heterogeneous environment

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International Journal of Biomathematics 2020年第7期13卷 29-50页

作者： Zhengdi Zhang Abdelrazig K.Tarboush faculty of science Jiangsu University Zhenjiang 212013P.R.China Department of Mathematics Faculty of Education University of KhartoumKhartoum 321Sudan

In this paper,we investigate a reaction-diffusion-advection model with expanding fronts,which models the spatial transmission of West Nile virus(WNv)in a heterogeneous environment.A free boundary problem is formulated and the global existence and uniqueness of the solution is *** addition to a classical basic reproduction number,the spatial-temporal basic reproduction number for the model with null Dirichlet boundary condition is introduced and the risk index associated with the virus in spatial setting is defined,and their properties are *** conditions for the WNv to vanish or spread are given,and the asymptotic behavior of the solution to the free boundary problem when the spreading occurs is *** results show that the initial number of infected populations and the expanding capability of the expanding fronts exhibit important impacts on the extinction or persistence of the virus.

关键词： West Nile virus free boundary advection risk index spreading and vanishing heterogeneous environment

A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations

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Journal of Sport and Health science 2024年第1期13卷 61-71页

作者： Alex E.Mohr David B.Pyne Geovana Silva Fogaça Leite Deborah Akins Jamie Pugh College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Research Institute for Sport and Exercise University of CanberraCanberraACT 2617Australia Laboratory of Functional Fermented Food Faculty of Pharmaceutical SciencesUniversity of São PauloSão Paulo 05508-030Brazil Research Institute for Sport and Exercise sciences Liverpool John Moores UniversityLiverpool L33AFUK

Background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public *** has also been an increased research focus within the realm of sports science and exercise medicine on the athletic gut ***,compared to other ergogenic aids and dietary supplements,probiotics present unique study *** objectives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active ***:Four databases(MEDLINE,CINAHL,Cochrane CENTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active *** intervention with probiotics and inclusion of a control and/or placebo group were *** peer-reviewed articles in English were considered,and there were no date *** were extracted and presented in tabular form to detail study protocols,characteristics,and *** in randomized controlled trials was determined with the RoB 2.0 ***:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over *** half the studies used a single probiotic and the other half a multi-strain *** probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 *** than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut *** sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated ***-level adverse events were reported in only 2 studies,although the methodology of reporting varied *** risk of bias was generally low,although details on randomization were lacking in some s

关键词： Exercise Experimental methodology Gastrointestinal symptoms Gut microbiota Probiotic supplementation

Task Scheduling Optimization in Cloud Computing by Rao Algorithm

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Computers, Materials & Continua 2022年第9期72卷 4339-4356页

作者： A.Younes M.KhElnahary Monagi H.Alkinani Hamdy H.El-Sayed faculty of Computers and Information Department of Computer ScienceSohag UniversitySohag82524Egypt Department of Computer science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia

Cloud computing is currently dominated within the space of highperformance distributed computing and it provides resource polling and ondemand services through the ***,task scheduling problem becomes a very important analysis space within the field of a cloud computing environment as a result of user’s services demand modification *** main purpose of task scheduling is to assign tasks to available processors to produce minimum schedule length without violating precedence *** heterogeneous multiprocessor systems,task assignments and schedules have a significant impact on system *** the heuristic-based task scheduling algorithm,the different processes will lead to a different task execution time(makespan)on a heterogeneous computing ***,a good scheduling algorithm should be able to set precedence efficiently for every subtask depending on the resources required to reduce(makespan).In this paper,we propose a new efficient task scheduling algorithm in cloud computing systems based on RAO algorithm to solve an important task and schedule a heterogeneous multiple processing *** basic idea of this process is to exploit the advantages of heuristic-based algorithms to reduce space search and time to get the best *** evaluate our algorithm’s performance by applying it to three examples with a different number of tasks and *** experimental results show that the proposed approach significantly succeeded in finding the optimal solutions than others in terms of the time of task implementation.

关键词： Heterogeneous processors RAO algorithm heuristic algorithms task scheduling multiprocessing cloud computing

Wave profile analysis of a couple of(3+1)-dimensional nonlinear evolution equations by sine-Gordon expansion approach

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Journal of Ocean Engineering and science 2022年第3期7卷 272-279页

作者： Md.Rezwan Ahamed Fahim Purobi Rani Kundu Md.Ekramul Islam M.Ali Akbar M.S.Osman Department of Mathematics Pabna University of Science and TechnologyBangladesh Department of Applied Mathematics University of RajshahiBangladesh Department of Mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Mathematics Faculty of Applied ScienceUmm Alqura UniversityMakkah 21955Saudi Arabia

The(3+1)-dimensional Kadomtsev-Petviashvili and the modified KdV-Zakharov-Kuznetsov equations have a significant impact in modern science for their widespread applications in the theory of long-wave propagation,dynamics of shallow water wave,plasma fluid model,chemical kinematics,chemical engineering,geochemistry,and many other *** this article,we have assessed the effects of wave speed and physical parameters on the wave contours and confirmed that waveform changes with the variety of the free factors in *** a result,wave solutions are extensively analyzed by using the balancing condition on the linear and nonlinear terms of the highest order and extracted different standard wave configurations,containing kink,breather soliton,bell-shaped soliton,and periodic *** extract the soliton solutions of the high-dimensional nonlinear evolution equations,a recently developed approach of the sine-Gordon expansion method is used to derive the wave solutions *** sine-Gordon expansion approach is a potent and strategic mathematical tool for instituting ample of new traveling wave solutions of nonlinear *** study established the efficiency of the described method in solving evolution equations which are nonlinear and with higher dimension(HNEEs).Closed-form solutions are carefully illustrated and discussed through diagrams.

关键词： Sine-Gordon expansion approach Kadomtsev-Petviashvili equation modified KdV-Zakharov-Kuznetsov equation soliton solutions

Apex Frame Spotting Using Attention Networks for Micro-Expression Recognition System

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Computers, Materials & Continua 2022年第12期73卷 5331-5348页

作者： Ng Lai Yee Mohd Asyraf Zulkifley Adhi Harmoko Saputro Siti Raihanah Abdani Department of Electrical Electronic and Systems EngineeringUniversiti Kebangsaan MalaysiaBangi43600Malaysia faculty of Mathematics and Natural science Universitas IndonesiaDepok16424Indonesia faculty of Humanities Management and ScienceUniversiti Putra Malaysia Bintulu CampusBintulu97008Malaysia

Micro-expression is manifested through subtle and brief facial movements that relay the genuine person’s hidden *** a sequence of videos,there is a frame that captures the maximum facial differences,which is called the apex ***,apex frame spotting is a crucial sub-module in a micro-expression recognition ***,this spotting task is very challenging due to the characteristics of micro-expression that occurs in a short duration with low-intensity muscle ***,most of the existing automated works face difficulties in differentiating micro-expressions from other facial ***,this paper presents a deep learning model with an attention mechanism to spot the micro-expression apex frame from optical flow *** attention mechanism is embedded into the model so that more weights can be allocated to the regions that manifest the facial movements with higher *** method proposed in this paper has been tested and verified on two spontaneous micro-expression databases,namely Spontaneous Micro-facial Movement(SAMM)and Chinese Academy of sciences Micro-expression(CASME)II *** proposed system performance is evaluated by using the Mean Absolute Error(MAE)metric that measures the distance between the predicted apex frame and the ground truth *** best MAE of 14.90 was obtained when a combination of five convolutional layers,local response normalization,and attention mechanism is used to model the apex frame *** with limited datasets,the results have proven that the attention mechanism has better emphasized the regions where the facial movements likely to occur and hence,improves the spotting performance.

关键词： Deep learning convolutional neural networks emotion recognition

An Advanced Stochastic Numerical Approach for Host-Vector-Predator Nonlinear Model

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Computers, Materials & Continua 2022年第9期72卷 5823-5843页

作者： Prem Junswang Zulqurnain Sabir Muhammad Asif Zahoor Raja Soheil Salahshour Thongchai Botmart Wajaree Weera Department of Statistics Faculty of ScienceKhon Kaen UniversityKhon Kaen40002Thailand Department of Mathematics and Statistics Hazara UniversityMansehraPakistan Future Technology Research Center National Yunlin University of Science and TechnologyDouliouYunlin64002Taiwan faculty of Engineering and Natural sciences Bahcesehir UniversityIstanbulTurkey Department of Mathematics Faculty of ScienceKhon Kaen UniversityKhon Kaen40002Thailand

A novel design of the computational intelligent framework is presented to solve a class of host-vector-predator nonlinear model governed with set of ordinary differential *** host-vector-predator nonlinear model depends upon five groups or classes,host plant susceptible and infected populations,vectors population of susceptible and infected individuals and the predator *** unsupervised artificial neural network is designed using the computational framework of local and global search competencies of interior-point algorithm and genetic *** solving the hostvector-predator nonlinear model,a merit function is constructed using the differential model and its associated boundary *** optimization of this merit function is performed using the computational strength of designed integrated heuristics based on interior point method and genetic *** the comparison,the obtained numerical solutions of networks models optimized with efficacy of global search of genetic algorithm and local search with interior point method have been compared with the Adams numerical solver based results or ***,the statistical analysis will be performed to check the reliability,robustness,viability,correctness and competency of the designed integrated heuristics of unsupervised networks trained with genetic algorithm aid with interior point algorithm for solving the biological based host-vector-predator nonlinear model for sundry scenarios of paramount interest.

关键词： Nonlinear host-vector-predator system adams results global/local search methods optimization neural networks statistical analysis