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Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese Physics B 2024年第2期33卷 108-114页

作者： U.S.mahabaleshwar G.P.Vanitha L.m.Pérez Emad H.Aly I.Pop Department of Studies in mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

Regional trends and petrologic factors inhibit global interpretations of zircon trace element compositions

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Geoscience Frontiers 2024年第5期15卷 300-307页

作者： Nick m.W.Roberts Christopher J.Spencer Stephen Puetz C.Brenhin Keller Simon Tapster Geochronology and Tracers Facility British Geological SurveyNottingham NG125GGUK Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonOntarioCanada Atkinson Dr Suite 704HonoluluHI 96814USA Department of Earth Sciences Dartmouth CollegeHanoverNew HamphireUSA

The trace element composition of zircon reveals information about the melt that they are derived from,as such,detrital zircon trace element compositions can be used to interrogate melt compositions,and thus the evolution of the continental crust in time and ***,we present a global database of detrital zircon compositions and use it to test whether average global trends for five common petrogenetic proxies truly represent secular changes in continental *** demonstrate that the secular trend is broadly comparable across continental regions for Ti-in-zircon temperatures,but for other trace element ratios interrogated,secular trends are highly variable between continental *** trace element ratios result from multiple petrologic variables,we argue that these petrogenetic proxies can be overinterpreted if projected to global geologic *** particular,we caution against the interpretation of crustal thickness from trace elements in zircon,and we argue that our results negate current hypotheses concerning secular changes in crustal thickness.

关键词： Detrital zircon Trace elements Secular change Eu anomaly Crustal thickness

Computational Prediction of micro RNAs from Toxoplasma gondii Potentially Regulating the Hosts' Gene Expression

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Genomics, Proteomics & Bioinformatics 2014年第5期12卷 228-238页

作者： müs?erref Duygu saar Caner Bagc? Jens Allmer molecular Biology and Genetics Izmir Institute of Technology Urla Izmir 35430 Turkey Biotechnology Izmir Institute of Technology Urla Izmir 35430 Turkey Bionia Incorporated IZTEKGEB A8 Urla Izmir 35430 Turkey

microRNAs （miRNAs） were discovered two decades ago, yet there is still a great need for further studies elucidating their genesis and targeting in different phyla. Since experimental discovery and validation of miRNAs is difficult, computational predictions are indispensable and today most computational approaches employ machine learning. Toxoplasma gondii, a parasite residing within the cells of its hosts like human, uses miRNAs for its post-transcriptional gene reg- ulation. It may also regulate its hosts＇ gene expression, which has been shown in brain cancer. Since previous studies have shown that overexpressed miRNAs within the host are causal for disease onset, we hypothesized that T. gondii could export miRNAs into its host cell. We computationally predicted all hairpins from the genome of T. gondii and used mouse and human models to filter possible candidates. These were then further compared to known miRNAs in human and rodents and their expression was examined for T. gondii grown in mouse and human hosts, respectively. We found that among the millions of potential hairpins in T. gondii, only a few thousand pass filtering using a human or mouse model and that even fewer of those are expressed. Since they are expressed and differentially expressed in rodents and human, we suggest that there is a chance that T. gondii may export miRNAs into its hosts for direct regulation.

关键词： Toxoplasma gondii microRNA Regulation Host interaction Parasite

Seasonal variability in CDOm absorption and fluorescence properties in the Barataria Basin,Louisiana,Usa

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Journal of Environmental Sciences 2010年第10期22卷 1481-1490页

作者： Shatrughan Singh Eurico D'sa Erick Swenson Department of Oceanography and Coastal Sciences Louisiana State University

Absorption and fluorescence properties of chromophoric dissolved organic matter （CDOm） along a 124 km transect in the Barataria Basin, a large estuary located in Louisiana, Usa, were investigated during high and low flow periods of the mississippi River in the spring and winter of 2008-2009. mean CDOm absorption at 355 nm from the marine to the freshwater end member stations ranged from （3.25 ± 0.56） to （20.76 ± 2.43） m^-1 for the three month high flow period whereas it varied from （1.48 ± 1.08） to （25.45 ± 7.03） m^-1 for the same stations during low flow period. Corresponding salinity values at these stations indicated the influence of river and shelf exchanges in the lower basin and precipitation and runoff in the upper basin. An inverse relationship of CDOm absorbance and fluorescence with salinity observed in the basin could he a useful indicator of salinity. CDOm fluorescence also varied over a large range showing an approximately 8 to 12-fold increase between the marine and freshwater end members for the two flow seasons. Excitation-emission matrix spectral plots indicated the presence of various fluorescence components with highest being the A-peak, lowest the T-peak, and the C and m-peaks showing similar trends along the transect. During low flow season the A/C ratio were well correlated with station locations indicating increased terrestrial influence towards the upper basin. CDOm absorption and fluorescence at 355 nm were highly correlated and independent of CDOm sources suggesting that fluorescence could be used to characterize CDOm in the basin.

关键词： Barataria Basin chromophoric dissolved organic matter CDOm fluorescence excitation-emission matrix

A review of control strategies used for morphing aircraft applications

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Chinese Journal of Aeronautics 2024年第4期37卷 436-463页

作者： muhammed S.PARANCHEERIVILAKKAThiL Jafar S.PILAKKADAN Rafic m.AJAJ mohammadreza AmOOZGAR Davood AsaDI Yahya ZWEIRI michael I.FRISWELL Department of Aerospace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Aerospace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of mechanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Department of Aerospace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

This paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. The first area is related to precise control of the shape of morphing concepts for various flight conditions. The second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. The third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. The design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. The aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low Technology Readiness Level(TRL) to real-life applications. This critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. This ranges from simple Proportional Integral Derivative(PID) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. This includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.

关键词： Control strategies morphing aircraft Shape morphing Flight dynamics Aeroelasticity

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多年冻土区静钻根植桩回冻过程温度场研究

石家庄铁道大学学报（自然科学版） 2024年第1期37卷 100-106页

作者：詹钦鹏王彪王飒石家庄铁道大学土木工程学院河北石家庄050043

基于传热学理论,给出桩土温度场偏微分方程及边界条件,结合低温稳定多年冻土区地质背景,通过有限元数值分析求解,分析静钻根植桩回冻过程桩土温度场随时间的分布变化规律,讨论水泥掺入量及水泥土的水泥浆体初始拌入温度对回冻过程的影响... 详细信息

基于传热学理论,给出桩土温度场偏微分方程及边界条件,结合低温稳定多年冻土区地质背景,通过有限元数值分析求解,分析静钻根植桩回冻过程桩土温度场随时间的分布变化规律,讨论水泥掺入量及水泥土的水泥浆体初始拌入温度对回冻过程的影响.结果表明,地表下2m以内桩土温度受大气温度影响较明显,水化热对1.5倍桩径以外及桩底1~2m以下范围桩土温度影响甚微,17 d后桩侧温度回冻至0℃,27d桩侧温度降至-0.5℃以下;水泥浆体初始拌入温度每升高5℃,回冻时间增长5~6 d;水泥掺入量每减少10%,回冻时间缩短1~2 d.静钻根植桩的温度场同样受水化热影响,但回冻时间较短;通过调整水泥浆体配合比和降低水泥浆体初始拌入温度可兼顾水泥土强度和回冻时间要求,达到提高承载力、缩短施工工期的目的.

关键词：多年冻土静钻根植桩水化热水泥掺入量初始拌入温度

Analysis and optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第9期12卷 665-679页

作者： med Amine LARIBI Lotfi ROmDHANE sad ZEGHLOUL Laboratoire de Génie mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The dialytic method along with Denavit-Hartenberg parameters can be used to obtain these equations efficiently. A genetic algorithm （GA） has been used to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RSCR and RSPC （R： revolute; S： spherical; C： cylindrical; P： prismatic）, have illustrated the application of the GA to solve the problem of function generation and path generation. In some cases, the GA method becomes trapped in a local minimum. A combined GA-fuzzy logic （GA-FL） method is then used to improve the final result. The results show that GAs, combined with an adequate description of the mechanism, are well suited for spatial mechanism synthesis problems and have neither difficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for deterministic methods.

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (GA-FL) method Denevit-Hartenberg parameters mechanism synthesis

Arrhythmia Detection by Using Chaos Theory with machine Learning Algorithms

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Computers, materials & Continua 2024年第6期79卷 3855-3875页

作者： maie Aboghazalah Passent El-kafrawy Abdelmoty m.Ahmed Rasha Elnemr Belgacem Bouallegue Ayman El-sayed math and Computer Science Department Faculty of ScienceMenoufia UniversityShebin El-komEgypt College of Engineering Computer Science DepartmentEffat UniversityJeddahKingdom of Saudi Arabia Department of Computer Engineering College of Computer ScienceKing Khalid UniversityAbha61421Saudi Arabia Computer Science and Engineering Department Faculty of Electronic EngineeringMenoufia UniversityShebin El-komEgypt Climate Change Information Center and Expert Systems Agriculture Research CenterGizaEgypt

Heart monitoring improves life ***(ECGs or EKGs)detect heart *** learning algorithms can create a few ECG diagnosis processing *** first method uses raw ECG and time-series *** second method classifies the ECG by patient *** third technique translates ECG impulses into Q waves,R waves and S waves(QRS)features using richer *** ECG signals vary naturally between humans and activities,we will combine the three feature selection methods to improve classification accuracy and *** using all three approaches have not been examined till *** researchers found that machine Learning(mL)techniques can improve ECG *** study will compare popular machine learning techniques to evaluate ECG *** algorithms—Support Vector machine(SVm),Decision Tree,Naive Bayes,and Neural Network—compare categorization *** plus prior knowledge has the highest accuracy(99%)of the four mL *** characteristics failed to identify signals without chaos *** 99.8%classification accuracy,the Decision Tree technique outperformed all previous experiments.

关键词： ECG extraction ECG leads time series prior knowledge and arrhythmia chaos theory QRS complex analysis machine learning ECG classification

Nutritional epigenetics education improves diet and attitude of parents of children with autism or attention deficit/hyperactivity disorder

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World Journal of Psychiatry 2024年第1期14卷 159-178页

作者： Renee J Dufault Katherine m Adler David O Carpenter Steven G Gilbert Raquel A Crider College of Graduate Health Studies A.T.Still UniversityKirksvilleMO 63501United States Department of Research Food Ingredient and Health Research InstituteNaalehuHI 96772United States Department of Health Sciences University of New HavenWest HavenCT 06516United States Institute for Health and the Environment School of Public HealthState University of New YorkAlbanyNY 12222United States Department of Research Institute of Neurotoxicology and Neurological DisordersSeattleWA 98105United States Department of Statistics Food Ingredient and Health Research InstituteNaalehuHI 96772United States

BACKGROUND Unhealthy maternal diet leads to heavy metal exposures from the consumption of ultra-processed foods that may impact gene behavior across generations,creating conditions for the neurodevelopmental disorders known as autism and attention deficit/hyperactivity disorder(ADHD).Children with these disorders have difficulty metabolizing and excreting heavy metals from their bloodstream,and the severity of their symptoms correlates with the heavy metal levels measured in their *** may play a key role in helping parents reduce their ultra-processed food and dietary heavy metal intake by providing access to effective nutritional epigenetics *** To test the efficacy of nutritional epigenetics instruction in reducing parental ultra-processed food *** The study utilized a semi-randomized test and control group pretest-posttest pilot study design with participants recruited from parents having a learning-disabled child with autism or ***-two parents who met the inclusion criteria were randomly selected to serve in the test(n=11)or control(n=11)*** test group participated in the six-week online nutritional epigenetics tutorial,while the control group did *** efficacy of the nutritional epigenetics instruction was determined by measuring changes in parent diet and attitude using data derived from an online diet survey administered to the participants during the pre and post intervention *** intake scores were derived for both ultra-processed and whole/organic *** sample t-tests were conducted to determine any differences in mean diet scores within each *** There was a significant difference in the diet scores of the test group between the pre-and post-intervention *** parents in the test group significantly reduced their intake of ultra-processed foods with a preintervention diet score of 70(mean=5.385,SD=2.534)and a post-intervention diet score of 113(mean=8.692,SD=1.750)and the

关键词： Epigenomics Parenteral nutrition Autism Attention deficit/hyperactivity disorder Ultra-processed foods Heavy metals