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Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L Silva L.A.o.Nunes S.M.Lima L.H.c.Andrade optical and Photothermal Spectroscopy group(gEoF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio optical thermometry Judd-ofelt Rare earths

A Rendezvous Mission to the Second Earth Trojan Asteroid 2020 XL_5 with Low-Thrust Multi-gravity Assist Techniques

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Research in Astronomy and Astrophysics 2024年第1期24卷 245-264页

作者： Shi-Hai Yang bo Xu Xin Li School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China

As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5) is ***, due to its high inclination and large eccentricity, direct impulsive transfer requires large amounts of fuel consumption. To address this challenge, we explore the benefits of electric propulsion and multi-gravity assist techniques for interplanetary missions. These two techniques are integrated in this mission design. The design of a low-thrust gravity-assist(LTgA) trajectory in multi-body dynamics is thoroughly investigated,which is a complex process. A comprehensive framework including three steps is presented here for optimization of LTgA trajectories in multi-body dynamics. The rendezvous mission to 2020 XL_(5) is designed with this three-step approach. The most effective transfer sequence among the outcomes involves Earth–Venus–Earth–Venus-2020 XL_(5). Numerical results indicate that the combination of electric propulsion and multi-gravity assists can greatly reduce the fuel consumption, with fuel consumption of 9.03%, making it a highly favorable choice for this rendezvous mission.

关键词： minor planets asteroids:general celestial mechanics Planetary Systems

How plants sense and respond to osmotic stress

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Journal of Integrative Plant Biology 2024年第3期66卷 394-423页

作者： bo Yu Dai-Yin chao Yang Zhao Shanghai center for Plant Stress Biology CAS Center for Excellence in Molecular Plant SciencesThe Chinese Academy of SciencesShanghai 200032China Key Laboratory of Plant carbon capture The Chinese Academy of SciencesShanghai 200032China National Key Laboratory of Plant Molecular genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyThe Chinese Academy of SciencesShanghai 200032China University of chinese Academy of Sciences Beijing 100049China

Drought is one of the most serious abiotic stresses to land *** sense and respond to drought stress to survive under water *** have studied how plants sense drought stress,or osmotic stress caused by drought,ever since charles Darwin,and gradually obtained clues about osmotic stress sensing and signaling in *** stress is a physical stimulus that triggers many physiological changes at the cellular level,including changes in turgor,cell wall stiffness and integrity,membrane tension,and cell fluid volume,and plants may sense some of these stimuli and trigger downstream *** this review,we emphasized water potential and movements in organisms,compared putative signal inputs in cell wall-containing and cell wall-free organisms,prospected how plants sense changes in turgor,membrane tension,and cell fluid volume under osmotic stress according to advances in plants,animals,yeasts,and bacteria,summarized multilevel biochemical and physiological signal outputs,such as plasma membrane nanodomain formation,membrane water permeability,root hydrotropism,root halotropism,casparian strip and suberin lamellae,and finally proposed a hypothesis that osmotic stress responses are likely to be a cocktail of signaling mediated by multiple *** also discussed the core scientific questions,provided perspective about the future directions in this field,and highlighted the importance of robust and smart root systems and efficient source-sink allocations for generating future high-yield stress-resistant crops and plants.

关键词： cell volume drought membrane tension osmotic stress turgor

Monogamy and polygamy for the generalized W-class states using unified-(q,s)entropy

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Science china(Physics,Mechanics & Astronomy) 2024年第1期67卷 10-22页

作者： bo Li Bing Xie Zhanjun Zhang Heng Fan School of computer and computing Science Hangzhou City UniversityHangzhou 310015China Department of Mathematics East China University of TechnologyNanchang 330013China School of Information&Electronic Engineering(Sussex Artificial Intelligence Institute) Zhejiang Gongshang UniversityHangzhou 310018China Institute of Physics Chinese Academy of SciencesBeijing 100190China

We describe the entanglement distribution and restricted shareability of the multipartite generalized W-class states and their reduced density matrix under arbitrary partitions by using monogamy and polygamy relation based on the unified-(q,s)***,we provide an analytical formula of unified-(q,s)entanglement(UE)and an analytical lower bound of unified-(q,s)entanglement of assistance(UEo A)for a reduced density matrix of a generalized W-class ***,we use these two analytical formulas to derive the monogamy and polygamy inequalities for a reduced density matrix of a qudit generalized W-class(gW)*** establish two partition-dependent residual entanglements based on the new monogamy relation,which is helpful to obtain a comprehensive analysis of entanglement dynamics of generalized W-class ***,we investigate tighter monogamy and polygamy relations based on the power ofαth(α≥0)for UE andβth(β≥0)for UEo A,*** results show that the entanglement distribution characteristics of generalized W-class states satisfying stronger constraints can be described more accurately.

关键词： monogamy polygamy multiqudit unified entropy

Pressure effects on metal/covalent-organic frameworks:structural and optical properties

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Science china chemistry 2024年第9期67卷 2890-2903页

作者： Yixuan Wang Yunfeng Yang Xinyi Yang bo Zou Synergetic Extreme condition High-Pressure Science center State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China

Metal-organic frameworks(MoFs)and covalent organic frameworks(coFs)with highly ordered porous structure,tunable bandgap,large specific surface area and structural diversity,provide an appealing platform for the development of stimulus response,sensing,imaging and *** various tuning methods,pressure engineering using the diamond anvil cell is a highly powerful in-situ technique,which can efficiently modulate the structural and optical properties of MoFs/*** is beyond the realization of traditional chemical *** review outlines the research progress in the experimentoriented discovery of new phases or unique properties under high pressure,including phase transition,abnormal compression,photoluminescence(PL)discoloration and ***,the improvement of PL quantum yield in MoFs could be achieved by pressure-treated engineering and hydrogen-bonding cooperativity *** also propose and establish the relationship between structure and optical properties under high ***,the challenge and outlook of the current fields are *** hope that this review will supply guidance for comprehending the development of high-pressure MoF/coF-related research fields,and offer novel strategies for designing more high-performance MoF/coF materials to ultimately expand their applications.

关键词： metal/covalent-organic frameworks pressure engineering phase transition abnormal compressive behaviors piezochromic behaviors emission enhancement

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Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants

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Science china(Physics,Mechanics & Astronomy) 2024年第9期67卷 43-50页

作者： Xiao-Bin Liang bo Li Shao-Ming Fei School of Mathematics and computer Science Shangrao Normal UniversityShangrao 334001China Quantum Information Research center Shangrao Normal UniversityShangrao 334001China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical ***,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement *** any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty *** demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation ***,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this ***,our findings resolve the conjecture posed in[***.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties.

关键词： uncertainty relation the tightest uncertainty constants optimal observable sets

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DNA g-Quadruplexes as Targets for Natural Product Drug Discovery

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Engineering 2024年第7期38卷 39-51页

作者： Kai-bo Wang Yingying Wang Jonathan Dickerhoff Danzhou Yang borch Department of Medicinal chemistry and Molecular Pharmacology College of PharmacyPurdue UniversityWest LafayetteIN 47907USA Purdue center for cancer Research Purdue UniversityWest LafayetteIN 47907USA Department of chemistry Purdue UniversityWest LafayetteIN 47907USA Purdue Institute for Drug Discovery Purdue UniversityWest LafayetteIN 47907USA Jiangsu Key Laboratory of Bioactive Natural Product Research&State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

DNA guanine(g)-quadruplexes(g4s)are unique secondary structures formed by two or more stacked gtetrads in g-rich DNA *** structures have been found to play a crucial role in highly transcribed genes,especially in cancer-related oncogenes,making them attractive targets for cancer ***,targeting oncogene promoter g4 structures has emerged as a promising strategy to address the challenge of undruggable and drug-resistant proteins,such as MYc,BcL2,KRAS,and *** products have long been an important source of drug discovery,particularly in the fields of cancer and infectious *** progress has recently been made in the discovery of naturally occurring DNA g4-targeting *** DNA g4s,such as MYc-g4,BcL2-g4,KRAS-g4,PDgFR-b-g4,VEgF-g4,and telomeric-g4,have been identified as potential targets of natural products,including berberine,telomestatin,quindoline,sanguinarine,isaindigotone,and many ***,we summarize and evaluate recent advancements in natural and nature-derived DNA g4 binders,focusing on understanding the structural recognition of DNA g4s by small molecules derived from *** also discuss the challenges and opportunities associated with developing drugs that target DNA g4s.

关键词： g-quadruplex Natural products Alkaloids cancer Promoter

Allogenic microglia replacement:A novel therapeutic strategy for neurological disorders

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Fundamental Research 2024年第2期4卷 237-245页

作者： Yanxia Rao bo Peng Department of Laboratory Animal Science MOE Frontiers Center for Brain ScienceFudan UniversityShanghai 200032China Department of Neurosurgery Huashan HospitalInstitute for Translational Brain ResearchState Key Laboratory of Medical NeurobiologyMOE Frontiers Center for Brain ScienceMOE Innovative Center for New Drug Development of Immune Inflammatory DiseasesFudan UniversityShanghai 200000China co-Innovation center of Neuroregeneration Nantong UniversityNantongJiangsu 226001China

Microglia are resident immune cells in the central nervous system(cNS)that play vital roles in cNS development,homeostasis and disease *** defects in microglia lead to microglial dysfunction,which in turn leads to neurological *** correction of the specific genetic defects in microglia in these disorders can lead to therapeutic *** genetic defect correction approaches are dependent on viral vectorbased genetic defect ***,the viruses used in these approaches,including adeno-associated viruses,lentiviruses and retroviruses,do not primarily target microglia;therefore,viral vector-based genetic defect corrections are ineffective in *** replacement is a novel approach to correct microglial genetic defects via replacing microglia of genetic defects with allogenic healthy *** this paper,we systematically review the history,rationale and therapeutic perspectives of microglia replacement,which would be a novel strategy for treating cNS disorders.

关键词： Microglia Replacement Microglia replacement Microglia depletion Microglia-free niche cSF1R

Evaluation of formation susceptibility and sand production potential in an offshore field,Niger Delta Basin,Nigeria

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Energy geoscience 2024年第1期5卷 1-11页

作者： David o.Ubuara Yinka A.olayinka godwin o.Emujakporue geoffrey c.Soronnadi-ononiwu Department of geology University of Port HarcourtNigeria Mease Energy Nigeria Limited Port HarcourtNigeria Department of geology University of IbadanNigeria Department of Physics University of Port HarcourtNigeria

Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil *** vulnerability of lithologic formations to wellbore instability and resultant sand production is investigated in the four delineated reservoirs of the“Areo”field,western part of Niger Delta *** foundation for establishing the geomechanical properties in this study was a 1-dimensional mechanical earth model,using gamma ray(gR),density(RHoB),compressional slowness(DTc),and shear slowness(DTS)*** the Areo oil field,two wells(well 001 and well 002)were *** evaluated formations are still primarily composed of compacted shale and unconsolidated sandstone,with reservoir sand units exhibiting lower elastic and rock strength properties than shale *** compressibility and porosity make sand more brittle,while low compressibility and porosity make shale stiffer due to high *** maximum force that can be applied to a shale unit without causing it to fail is 17.23 MPa,which is the maximum average rock strength of the *** means that shale requires more vertical stress or pressure than sand does in order to deform it(15.06 MPa).The three sand prediction approaches used in the analysis of sand production predictions have cut-off values that are higher than the average values of the *** Schlumberger sand production index method(S/I)indicates that the reservoir has potential for sand influx in the two wells,with the average of the four reservoirs studied in wells 001 and 002 being 1.551012 psi and 1.141012 psi ***,when a formation's sand production index is less than 1.241012 psi,as it is in this study,the formation is likely to produce *** findings support the notion that the defined sandstone units are highly unconsolidated and have a high potential for producing sands;therefore,sand control techniques must be factored in

关键词： Wireline log Stress geo-mechanicanical characterization Sand prediction Niger delta