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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 s.udies 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

A review of methane leakage from abandoned oil and gas wells:A case s.udy in lubbock,Texas,within the Permian Basin

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Energy Geoscience 2024年第3期5卷 1-12页

作者： stanley u.Opara Chinedu J.Okere Bob l.Herd Department of Petrol.um Engineering Texas Tech UniversityTXUSA

In the pursuit of global net zero carbon emissions and climate change mitigation,ongoing research into sustainable energy s.urces and emission control is *** review examines methane leakage from abandoned oil and gas(AOG)wells,focusing particularly on lubbock,a geographic area situated within the larger region known as the Permian Basin in West Texas.united *** objective is to assess the extent and environmental implications of methane leakage from these *** analysis integrates pertinent literature,governmental and industry data,and prior lubbock *** affecting methane leakage,including well integrity,geological characteristics,and human activities,are *** research estimates 1781 drilled wells in lubbock,forming a foundation for targeted assessments and monitoring due to historical drilling *** hierarchy of well statuses in lubbock highlights the prevalence of“active oil wells,”trailed by“plugged and abandoned oil wells”and“inactive oil wells.”Methane leakage potential aligns with these well types.underscoring the importance of strategic monitoring and *** analysis notes a zenith in“drilled and completed”wells during *** our s.udy's case analysis and literature review reiterate the critical significance of assessing and mitigating methane emissions from AOG wells,it's important to clarify that the research does not directly provide methane leakage ***,it contextualizes the is.ue's magnitude and emphasizes the well type and status analysis's role in targeted mitigation *** summary,our research deepens our understanding of methane leakage,aiding informed decision-making and policy formulation for environmental *** clarifying well type implications and historical drilling patterns,we aim to contribute to effective strategies in mitigating methane emissions from AOG wells.

关键词： Net zero carbon emissions Climate change mitigation Methane emission control Abandoned oil and gas(AOG)well Permian Basin

A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

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Journal of Palaeogeography 2024年第1期13卷 149-164页

作者： Da-Wei lü Wen-Xu Du Zhi-Hui Zhang Yuan Gao tian-tian Wang Jin-Cheng Xu Ao-Cong Zhang Cheng-shan Wang shandong Provincial Key laboratory of Depositional Mineralization and sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina school of Earth sciences and Res.urces China University of GeosciencesBejing 100083China Institute of Earth sciences China University of Geosciences(Bejing)Beijing 100083China

The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this s.udy, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

关键词： Wildfire Cretaceous Atmospheric oxygen Taphonomy Charcoal

Promotion of structural plasticity in area V2 of visual cortex prevents against object recognition memory deficits in aging and Alzheimer's disease rodents

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Neural Regeneration Research 2024年第8期19卷 1835-1841页

作者： Irene Navarro-lobato Mariam Mas.udi-Martín Manuel F.lópez-Aranda Juan F.lópez-Téllez Gloria Delgado Pablo Granados-Durán Celia Gaona-Romero Marta Carretero-Rey sinforiano Posadas María E.Quiros-Ortega Zafar u.Khan laboratory of Neurobiology Centro de Investigaciones Médico Sanitarias(CIMES)University of MalagaMalagaSpain Department of Medicine Faculty of MedicineUniversity of MalagaMalagaSpain Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas(CIBERNED) Institute of Health Carlos IIIMadridSpain the Donders Institute for Brain Cognition and Behaviour Radboud UniversityNijmegenThe Netherlands the Brain Metastasis Group National Cancer Research Centre(CNIO)MadridSpain the Department of Neurobiology University of California-Los AngelesLos AngelesCAUSA

Memory deficit,which is often associated with aging and many psychiatric,neurological,and neurodegenerative diseases,has been a challenging is.ue for *** till now,all potential drug candidates have failed to produce satisfa ctory ***,in the search for a solution,we found that a treatment with the gene corresponding to the RGs14414protein in visual area V2,a brain area connected with brain circuits of the ventral stream and the medial temporal lobe,which is crucial for object recognition memory(ORM),can induce enhancement of *** this s.udy,we demonstrated that the same treatment with RGs14414in visual area V2,which is relatively unaffected in neurodegenerative diseases such as Alzheimer s disease,produced longlasting enhancement of ORM in young animals and prevent ORM deficits in rodent models of aging and Alzheimer’s ***,we found that the prevention of memory deficits was mediated through the upregulation of neuronal arbo rization and spine density,as well as an increase in brain-derived neurotrophic factor(BDNF).A knockdown of BDNF gene in RGs14414-treated aging rats and Alzheimer s disease model mice caused complete loss in the upregulation of neuronal structural plasticity and in the prevention of ORM *** findings suggest that BDNF-mediated neuronal structural plasticity in area V2 is crucial in the prevention of memory deficits in RGs14414-treated rodent models of aging and Alzheimer’s ***,our findings of RGs14414gene-mediated activation of neuronal circuits in visual area V2 have therapeutic relevance in the treatment of memory deficits.

关键词： behavioral performance brain-derived neurotrophic factor cognitive dys.unction episodic memory memory circuit activation memory deficits memory enhancement object recognition memory prevention of memory loss regulator of G protein signaling

structurally Flexible 2D spacer for suppressing the Electron-Phonon Coupling Induced Non-Radiative Decay in Perovskite solar Cells

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Nano-Micro letters 2024年第9期16卷 325-340页

作者： Ruikun Cao Kexuan sun Chang l.u Yuhong Mao Wei Guo Ping Ouyang Yuanyuan Meng Ruijia tian lisha Xie Xujie lü Ziyi Ge Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China school of Materials science and Chemical Engineering Ningbo UniversityNingbo 315211People’s Republic of China Center of Materials science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Center for High Pres.ure science and Technology Advanced Research(HPsTAR) Shanghai 201203People’s Republic of China

This s.udy presents experimental evidence of the dependence of non-radiative recombination processes on the electron-phonon coupling of perovskite in perovskite solar cells(PsCs).Via A-site cation engineering,a weaker electron-phonon coupling in perovskite has been achieved by introducing the structurally soft cyclohexane methylamine(CMA^(+))cation,which could serve as a damper to alleviate the mechanical stress caused by lattice oscillations,compared to the rigid phenethyl methylamine(PEA^(+))*** demonstrates a significantly lower non-radiative recombination rate,even though the two types of bulky cations have similar chemical passivation effects on perovskite,which might be explained by the suppressed carrier capture process and improved lattice geometry *** resulting PsCs achieve an exceptional power conversion efficiency(PCE)of 25.5%with a record-high opencircuit voltage(V_(OC))of 1.20 V for narrow bandgap perovskite(FAPbI_(3)).The established correlations between electron-phonon coupling and non-radiative decay provide design and screening criteria for more effective passivators for highly efficient PsCs approaching the shockley-Queisser limit.

关键词： Electron-phonon coupling A-site cation engineering Non-radiative recombination

Energy beam-based direct and assisted polishing techniques for diamond:A review

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International Journal of Extreme Manufacturing 2024年第1期6卷 93-124页

作者： Zhuo li Feng Jiang Zhengyi Jiang Zige tian tian Qiu Tao Zhang Qiuling Wen Xizhao lu Jing lu Hui Huang Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China school of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China state Key laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power ***,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of *** address these challenges,several polishing methods have been developed for both single crystal diamond(sCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing *** this review,the characteristics and application scope of various polishing technologies for sCD and PCD are ***,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are *** current research progress,material removal mechanism,and infuencing factors of each polishing technology are *** some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the ***,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors

Off-Grid Compressed Channel Estimation with Parallel Interference Cancellation for Millimeter Wave Massive MIMO

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China Communications 2024年第3期21卷 51-65页

作者： l.u Jinru tian Yongqing l.u Danpu Zhang Zhilong Beijing laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and ConvergenceBeijing University of Posts and TelecommunicationsBeijing100876China

Millimeter wave(mmWave)massive multiple-input multiple-output(MIMO)plays an important role in the fifth-generation(5G)mobile communications and beyond wireless communication systems owing to its potential of high ***,channel estimation has become very challenging due to the use of massive MIMO antenna ***,the mmWave channel has strong sparsity in the spatial angle domain,and the compressed sensing technology can be used to convert the original channel matrix into the sparse matrix of discrete angle *** the high-dimensional channel matrix estimation is transformed into a sparse recovery problem with greatly reduced computational ***,the path angle in the actual scene appears randomly and is.unlikely to be completely located on the quantization angle grid,thus leading to the problem of power ***,multiple paths with the random distribution of angles will bring about serious interpath interference and further deteriorate the performance of channel *** address these off-grid is.ues,we propose a parallel interference cancellation assisted multi-grid matching pursuit(PIC-MGMP)algorithm in this *** proposed algorithm consists of three stages,including coarse estimation,refined estimation,and inter-path cyclic iterative inter-ference *** specifically,the angular resolution can be improved by locally refining the grid to reduce power leakage,while the inter-path interference is eliminated by parallel interference cancellation(PIC),and the two together improve the estimation *** results show that compared with the traditional orthogonal matching pursuit(OMP)algorithm,the normalized mean s.uare error(NMsE)of the proposed algorithm decreases by over 14dB in the case of 2 paths.

关键词： channel estimation compressed sensing inter-path interference millimeter wave massive MIMO off-grid parallel interference cancellation

unsynchronized butyrophilin molecules dictate cancer cell evasion of Vγ9Vδ2 T-cell killing

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Cel.ular & Molecular Immunology 2024年第4期21卷 362-373页

作者： Zeguang Wu Qiezhong lamao Meichao Gu Xuanxuan Jin Ying l.u Feng tian Ying Yu Pengfei Yuan s.uaixin Gao Thomas s.Fulford Adam P.uldrich Catherine C.l Wong Wensheng Wei Biomedical Pioneering Innovation Center Peking-Tsinghua Center for Life SciencesPeking University Genome Editing Research CenterState Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesPeking University100871BeijingChina EdiGene Inc. Life Science ParkChangping District102206BeijingChina Center for Precision Medicine Multi-Omics Research Peking University Health Science CenterPeking University100191BeijingChina Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity The University of MelbourneParkvilleVIC3010Australia Cancer Immunology Program Peter MacCallum Cancer CentreMelbourneVICAustralia state Key laboratory for Complex Severe and Rare DiseasesClinical Research InstitutePeking Union Medical College HospitalChinese Academy of Medical Science&Peking Union Medical CollegePeking-Tsinghua Center for Life Sciences100871BeijingChina

Vγ9Vδ2 T cells are specialized effector cells that have gained prominence as immunotherapy agents due to their ability to target and kill cells with altered pyrophosphate *** our effort to understand how cancer cells evade the cell-killing activity of Vγ9Vδ2 T cells,we performed a comprehensive genome-scale CRIsPR screening of cancer *** found that four molecules belonging to the butyrophilin(BTN)family,specifically BTN2A1,BTN3A1,BTN3A2,and BTN3A3,are critically important and play unique,nonoverlapping roles in facilitating the destruction of cancer cells by primary Vγ9Vδ2 T *** coordinated function of these BTN molecules was driven by synchronized gene expression,which was regulated by IFN-γsignaling and the RFX ***,an enzyme called QPCTl was shown to play a key role in modifying the N-terminal glutamine of these BTN proteins and was found to be a crucial factor in Vγ9Vδ2 T cell killing of cancer *** our research,we offer a detailed overview of the functional genomic mechanisms that underlie how cancer cells escape Vγ9Vδ2 T ***,our findings shed light on the importance of the harmonized expression and function of gene family members in modulating T-cell activity.

关键词： Butyrophilin Vγ9Vδ2 T-cell Cancer-specific immune evasion Glutaminyl-peptide cyclotransferase-like Pyrophosphate metabolite Immunotherapy

Evaluation of arsenic pol.ution in field-contaminated soil at the soil’s actual pH

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Journal of Environmental sciences 2024年第10期144卷 137-147页

作者： tiancong Gao Haixia tian Huimin Niu Mallavarapu Megharaj Wenxiang He College of Natural Res.urces and Environment Northwest A&F UniversityKey Laboratory of Plant Nutrition and Agro-environment in Northwest ChinaMinistry of AgricultureYanglingShaanxi 712100China Global Centre for Environmental Remediation College of EngineeringScience and EnvironmentUniversity of NewcastleCallaghanNSW 2308Australia

The pol.ution and ecological risks posed by arsenic(As)entering the soil are the major environmental challenges faced by human *** phosphatase can serve as a useful indicator for assessing As contamination under specific soil pH ***,the s.udy of phosphatase kinetics in long-term field As-contaminated soil remains.unclear,presenting a significant obstacle to the monitoring and evaluation of As pol.ution and *** purpose of this s.udy was to determine phosphatase activity and explore enzyme kinetics in soils subjected to long-term field As *** revealed that the soil phosphatase activity varied among the tested soil samples,depending on the concentrations of *** relationship between total As,As fractions and phosphatase activity was found to be significant through negative exponential function *** parameters,including maximum reaction velocity(Vmax),Michaelis constant(Km)and catalytic efficiency(V_(max)/K_(m)),ranged from 3.14×10^(−2)–53.88×10^(−2) mmol/(l·hr),0.61–7.92 mmol/l,and 0.46×10^(−2)–11.20×10^(−2) hr−1,*** and Vmax/Km of phosphatase decreased with increasing As pol.ution,while Km was less ***,Vmax/Km showed a significant negative correlationwith all As fractions and total *** ecological doses(ED10)for the complete inhibition and partial inhibition models ranged from0.22–70.33 mg/kg and 0.001–55.27 mg/kg,respectively,indicating that V_(max)/K_(m) can be used as an index for assessing As pol.ution in field-contaminated *** s.udy demonstrated that the phosphatase kinetics parameters in the soil’s pH system were better indicators than the optimal pH for evaluating the field ecotoxicity of As.

关键词： Arsenic pol.ution Ecological risk soil phosphatase Enzyme kinetics Catalytic efficiency(V_(max)/K_(m))