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chinese chemical Letters 2024年第7期35卷 264-270页

作者： Yan-Bo Li Yi Li liang Yin cAS Key Laboratory of Synthetic.c.emistry of Natural Substances Centre for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

A copper(Ⅰ)-catalyzed diastereodivergent addition of phosphinothioates(HP(S)ROR')toα,β-unsaturated thioamides is disclosed,which constructs vicinal P-chiral and c.c.iral centers in generally high diastereoand *** this reaction,the kinetic resolution of HP(S)ROR'occurs,which affords(R)-HP(S)Ph OMe in high enantioselectivity in the addition with(R,R)-Ph-BPE as the *** is found through control experiment that dual“soft-soft”interaction,indicated by both1H and31P NMR experiments,is indispensable in the present *** first“soft-soft”interaction between copper(Ⅰ)catalyst and HP(S)ROR'enables facile deprotonation to generate nucleophilic.c.]-SPROR'*** second one between the[cu]-SPROR'species andα,β-unsaturated thioamides facilitated the nucleophilic ***,both Michael adducts and(R)-HP(S)PhOMe are easily converted to synthetically useful compounds.

关键词： copper catalysis Asymmetric.c.talysis Diastereodivergent synthesis P-chirality "Soft-soft"interaction

Extreme climate sparks record boreal wildfires and carbon surge in 2023

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The Innovation 2024年第4期5卷 7-8页

作者： Lili liang Shijing liang Zhenzhong Zeng School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

While human activities,such as the burning of fossil fuels,are the primary contributors to the increase in atmospheric.c._(2) levels,large-scale wildfires can exacerbate this *** years with extensive and severe wildfires,additional carbon emissions can significantly perturb global carbon budgets,1 thereby impeding existing endeavors to mitigate climate ***,a recent investigation reported a notable surge in carbon emissions originating from boreal forests in 2021,2 reaching an estimated 0.48 gigatons of carbon(Gt c).However,this record proved *** 1 shows that by September 2023,the carbon emissions of boreal forests exhibited an unprecedented increase,primarily attributed to the canadian boreal region,reaching 0.86 Gt *** consequences extend beyond geographical borders,as wildfires occurring hundreds of kilometers away resulted in the worst air quality in New York and *** increasing severity of boreal forest wildfires is accompanied by growing public.c.ncern,suggesting the potential proximity to or crossing of a critical tipping point in the ecological functioning of boreal forests.

关键词： surge record Figure

Effects of layer interactions on instantaneous stability of finite Stokes flows

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 69-84页

作者： chen ZHAO Zhenli cHEN c.T.MUTASA Dong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

The stability analysis of a finite Stokes layer is of practical importance in flow control. In the present work, the instantaneous stability of a finite Stokes layer with layer interactions is studied via a linear stability analysis of the frozen phases of the base flow. The oscillations of two plates can have different velocity amplitudes, initial phases, and frequencies. The effects of the Stokes-layer interactions on the stability when two plates oscillate synchronously are analyzed. The growth rates of two most unstable modes when δ ckness and the half height of the channel, respectively. However, their vorticities are different. The vorticity of the most unstable mode is symmetric, while the other is asymmetric. The Stokes-layer interactions have a destabilizing effect on the most unstable mode when δ ct when δ > 0.68. However, the interactions always have a stabilizing effect on the other unstable mode. It is explained that one of the two unstable modes has much higher dissipation than the other one when the Stokes-layer interactions are strong. We also find that the stability of the Stokes layer is closely related to the inflectional points of the base-flow velocity profile. The effects of inconsistent velocity-amplitude, initial phase, and frequency of the oscillations on the stability are analyzed. The energy of the most unstable eigenvector is mainly distributed near the plate of higher velocity amplitude or higher oscillation frequency. The effects of the initial phase difference are complicated because the base-flow velocity is extremely sensitive to the initial phase.

关键词： finite Stokes layer instantaneous stability Stokes-layer interaction asynchronous oscillation

Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function

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Journal of Sport and Health Science 2024年第2期13卷 233-244页

作者： Xiang Ren Tan Mary c.Stephenson Sharifah Badriyah Alhadad Kelvin W.Z.Loh Tuck Wah Soong Jason K.W.Lee Ivan c.c.Low Health and Social Sciences Singapore Institute of TechnologySingapore 138683Singapore Human Potential Translational Research Programme Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore centre for Translational Magnetic Resonance Research Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117549Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117593Singapore Heat Resilience and Performance centre Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117510Singapore N.1 Institute for Health National University of SingaporeSingapore 117456Singapore campus for Research Excellence and Technological Enterprise(cREATE) Singapore 138602Singapore

Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive *** heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and ***:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,*** a separate trial,blended ice was ingested before and during exercise as a cooling *** were compared to a control condition with seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging ***:T_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).With the development of hyperthermia,T_(br)increases and dovetails with the rising T_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive *** function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital ***,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural ***:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance.

关键词： Brain functional activity cognition Heat stress Hyperthermia Motor function

Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.Huang K.Jiang c.N.Wu H.Peng P.c.hen R.Li H.B.Zhuo c.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Radiative decays D*(s)→ D(s)γ in covariant confined quark model

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chinese Physics c 2024年第2期48卷 45-56页

作者： c.T.Tran M.A.Ivanov P.Santorelli Q.c.Vo Department of Physics HCMC University of Technology and EducationVo Van Ngan 1700000 Ho Chi Minh CityVietnam Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear Research141980 DubnaRussia Dipartimento di Fisica"E.Pancini" Universitàdi Napoli Federico ⅡComplesso Universitario di Monte S.AngeloVia CintiaEdificio 680126 NapoliItaly Istituto Nazionale di Fisica Nucleare Sezione di Napoli80126 NapoliItaly University of Science 700000 Ho Chi Minh CityVietnam

Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BESⅢ*** radiative couplings gD*Dγencoding nonperturbative QcD effects are calculated in the framework of the covariant confined quark model developed by *** compare our results with other theoretical studies and experimental *** couplings(in GeV-1)|g(D*+D+γ)|=0.45(9)and|g(D*0D0γ)|=1.72(34)calculated in our model agree with the corresponding experimental data|g(D*+D+γ)|=0.47(7)and|g(D*0D0γ)|=1.77(16).The most interesting case is the decay Ds*→Dsγ,for which a recent prediction based on light-cone sum rules at next-to-leading order|gDs*Dsγ|=0.60(19)deviates from the first(and only to date)lattice QcD result|gDs*Dsγ|=0.11(2)at nearly3σ.Our calculation yields|gDs*Dsγ|=0.29(6),which falls somehow between the two mentioned results,although it is larger than those predicted in other studies using quark models or QcD sum rules.

关键词： covariant quark model radiative decay charmed meson

Pathogenic and therapeutic role of exosomes in neurodegenerative disorders

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Neural Regeneration Research 2024年第1期19卷 75-79页

作者： christa c.Huber Hongmin Wang Division of Basic Biomedical Sciences Sanford School of MedicineUniversity of South DakotaVermillionSDUSA

Neurodegenerative disorders affect millions of people worldwide,and the prevalence of these disorders is only projected to rise as the number of people over 65 will drastically increase in the coming *** therapies exist to aid in symptomatic relief,effective treatments that can stop or reve rse the progress of each neurodegenerative disease are ***,research on the role of extracellular vesicles as disease markers and therapeutics has been intensively ***,30-150 nm in diameter,are one type of extracellular vesicles facilitating cell-to-cell *** are thought to play a role in disease propagation in a variety of neurodegenerative diseases,such as Alzheimer's disease,Parkinson s disease,and amyotrophic lateral ***,the exosomes derived from the patients are an invaluable source of disease *** the other hand,exosomes,especially those derived from stem cells,could serve as a therapeutic for these disorders,as seen by a rapid increase in clinical trials investigating the therapeutic effic.c. of exosomes in different neurological *** review summarizes the pathological burden and therapeutic approach of exosomes in neurodegenerative *** also highlight how heat shock increases the yield of exosomes while still maintaining their therapeutic ***,this review concludes with outstanding questions that remain to be addressed in exosomal research.

关键词： aging Alzheimer's disease biomarker drug exosome extracellular vesicle neurodegenerative disease Parkinson's disease therapy

GRP7 phase separation as an interpreter of temperature cues

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Molecular Plant 2024年第6期17卷 842-844页

作者： Sunita Pathak Lucia c.Strader Department of Biology Duke UniversityDurhamNCUSA

Plants are exposed to a range of daily and seasonal temperatures and thus are required to regulate their cellular processes under fluctuating temperature *** various temperature-responsive genes,GLYcINE-RIcH RNA BINDING PROTEIN7(GRP7)encodes a glycine-rich RNA-binding protein that provides freezing tolerance to plants(carpenter et al.,1994;Kim et al.,2008)by acting as an RNA chaperone(Kwak et al.,2011).

关键词： conditions. separation

Automated Machine Learning Algorithm Using Recurrent Neural Network to Perform Long-Term Time Series Forecasting

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computers, Materials & continua 2024年第3期78卷 3529-3549页

作者： Ying Su Morgan c.Wang Shuai Liu Department of Statistics and Data Science University of Central FloridaOrlandoFL32816-2370USA School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing100048China

Long-term time series forecasting stands as a crucial research domain within the realm of automated machine learning(AutoML).At present,forecasting,whether rooted in machine learning or statistical learning,typically relies on expert input and necessitates substantial manual *** manual effort spans model development,feature engineering,hyper-parameter tuning,and the intricate construction of time series *** complexity of these tasks renders complete automation unfeasible,as they inherently demand human intervention at multiple *** surmount these challenges,this article proposes leveraging Long Short-Term Memory,which is the variant of Recurrent Neural Networks,harnessing memory cells and gating mechanisms to facilitate long-term time series ***,forecasting accuracy by particular neural network and traditional models can degrade significantly,when addressing long-term time-series ***,our research demonstrates that this innovative approach outperforms the traditional Autoregressive Integrated Moving Average(ARIMA)method in forecasting long-term univariate time *** is a high-quality and competitive model in time series prediction,and yet it requires significant preprocessing *** multiple accuracy metrics,we have evaluated both ARIMA and proposed method on the simulated time-series data and real data in both short and long ***,our findings indicate its superiority over alternative network architectures,including Fully connected Neural Networks,convolutional Neural Networks,and Nonpooling convolutional Neural *** AutoML approach enables non-professional to attain highly accurate and effective time series forecasting,and can be widely applied to various domains,particularly in business and finance.

关键词： Automated machine learning autoregressive integrated moving average neural networks time series analysis

Effects of interlayer spacing and applied pressure on the lanthanide transport in MoS2-based two-dimensional channels

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International Journal of Smart and Nano Materials 2024年第3期15卷 579-592页

作者： Qinsi Xiong chong Liu George c.Schatz Department of chemistry Northwestern UniversityEvanstonILUSA Pritzker School of Molecular Engineering University of ChicagoChicagoILUSA

Rare-earth elements(REEs)are critical to modern industry but difficult to separate due to their subtle and monotonic.c.anges in physico-chemical ***2-based two-dimensional(2D)materials offer novel opportunities for enhancing REE separation,exhibiting a distinct volcano-shaped transport performance distribution that peaks at Sm3+.However,the specific.c.ntributions of thermodynamic and kinetic factors to ion transport within 2D confinement remain *** this study,we conducted a series of non-equilibrium all-atom molecular dynamics(MD)simulations to explore the effects of interlayer spacing and external pressure on the transport of lanthanide ions inÅ-scale acetate functionalized 2D MoS2(MoS2-cOOH)*** examined ion entry and permeation rates,water flux,dehydration,and binding *** simulation results reveal that the transport trends of lanthanide ions are jointly driven by the dehydration degree and the relative-binding strengths of ions to water and to the acetate within the 2D ***,the dehydration pattern of lanthanide ions during permeation is closely linked to kinetic ***,this study provides a detailed atomistic understanding of the mechanisms under-lying lanthanide ion transport under *** findings point to the significant potential for tuning confinement and chemical functionalization withinÅ-scale channels for more efficient REE separation.

关键词： MoS_(2) 2D channels Lanthanide ions ion transport nanofluidics