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A light-powered molecular pump achieving transmembrane concentration gradient
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作者 Man Wu Chuandong Jia 《Chinese Journal of Structural Chemistry》 2025年第4期12-13,共2页
According to the second law of thermodynamics,spontaneous chemical processes will ultimately reach the equilibrium state with the lowest energy.However,in biological systems,there are numerous highenergy states far fr... According to the second law of thermodynamics,spontaneous chemical processes will ultimately reach the equilibrium state with the lowest energy.However,in biological systems,there are numerous highenergy states far from equilibrium.One typical example is the transmembrane ion-concentration gradient,which plays crucial roles in maintaining homeostasis,regulating cell volume,and enabling cell signaling.Transmembrane ion-concentration gradient is achieved by an active transport process that requires the input of energy and the action of pump proteins.Replicating this process with synthetic supramolecular systems is particularly challenging,requiring both the input of energy and very specific,spatiotemporal control over ion uptake and release.In nature,pump proteins,such as protein-based ion channels,have evolved highly intricate architectures to perform this function.In contrast,Aprahamian and coworkers recently developed a much simpler smallmolecule system that functions as a molecular ion pump,utilizing light energy to pump chloride ions across a hydrophobic barrier against the concentration gradient[1]. 展开更多
关键词 active transport process light powered molecular pump high energy states transmembrane concentration gradient ion concentration gradient maintaining homeostasisregulating equilibrium state chemical processes
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A high-throughput measurement of critical micelle concentrations based on absolute aggregation-caused quenching probes
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作者 Xin Ji Aun Raza +3 位作者 Jianping Qi Yi Lu Haisheng He Wei Wu 《Journal of Pharmaceutical Analysis》 2025年第3期651-653,共3页
Amphiphiles,including surfactants,have emerged as indispensable elements in materials science and pharmaceutical science,and their functions are highly relying on the critical micelle concentration(CMC)[1,2].Numerous ... Amphiphiles,including surfactants,have emerged as indispensable elements in materials science and pharmaceutical science,and their functions are highly relying on the critical micelle concentration(CMC)[1,2].Numerous fluorimetry-based probes have been developed to measure CMCs[3](Fig.S1).However,CMC measurements using these probes suffer from a time-consuming and laborious procedure and large uncertainties,primarily due to their poor photo-stabilities and highly fluctuating fluorescence backgrounds. 展开更多
关键词 high throughput measurement photo stabilities fluorescence backgrounds critical micelle concentration cmc numerous materials science critical micelle concentration fluorimetry based probes absolute aggregation caused quenching
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Vedolizumab serum trough concentrations with and without thiopurines in ulcerative colitis: The prospective VIEWS pharmacokinetics study
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作者 Thanaboon Chaemsupaphan Aviv Pudipeddi +4 位作者 Hui-Yu Lin Sudarshan Paramsothy Viraj C Kariyawasam Melissa Kermeen Rupert W Leong 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期102-112,共11页
BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thio... BACKGROUND Ulcerative colitis(UC)is a chronic inflammatory condition requiring continuous treatment and monitoring.There is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thiopurines on vedolizumab trough concentrations is unknown.AIM To investigate the exposure-response relationship of vedolizumab and the impact of thiopurine withdrawal in UC patients who have achieved sustained clinical and endoscopic remission during maintenance therapy.METHODS This is a post-hoc analysis of prospective randomized clinical trial(VIEWS)involving UC patients across 8 centers in Australia from 2018 to 2022.Patients in clinical and endoscopic remission were randomized to continue or withdraw thiopurine while receiving vedolizumab.We evaluated vedolizumab serum trough concentrations,presence of anti-vedolizumab antibodies,and clinical outcomes over 48 weeks to assess exposure-response asso-ciation and impact of thiopurine withdrawal.RESULTS There were 62 UC participants with mean age of 43.4 years and 42%were females.All participants received vedolizumab as maintenance therapy with 67.7%withdrew thiopurine.Vedolizumab serum trough concentrations remained stable over 48 weeks regardless of thiopurine use,with no anti-vedolizumab antibodies detected.Pa-tients with clinical remission had higher trough concentrations at week 48.In quartile analysis,a threshold of>11.3μg/mL was associated with sustained clinical remission,showing a sensitivity of 82.4%,specificity of 60.0%,and an area of receiver operating characteristic of 0.71(95%CI:0.49-0.93).Patients discontinuing thiopurine required higher vedolizumab concentrations for achieving remission.CONCLUSION A positive exposure-response relationship between vedolizumab trough concentrations and UC outcomes suggests that monitoring drug levels may be beneficial.While thiopurine did not influence vedolizumab levels,its with-drawal may necessitate higher vedolizumab trough concentrations to maintain remission. 展开更多
关键词 PHARMACOKINETIC Vedolizumab THIOPURINE Ulcerative colitis Trough concentration Antibody Inflammatory bowel diseases
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Impact of Pollutant Concentration and Particle Deposition on the Radiative Flow of Casson-Micropolar Fluid between Parallel Plates
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作者 Ghaliah Alhamzi Badr Saad T.Alkahtani +2 位作者 Ravi Shanker Dubey Vinutha Kalleshachar Neelima Nizampatnam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期665-690,共26页
Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing po... Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental management.Determining the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge concentrations.The waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution levels.This study aims to explore the Casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle deposition.To explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are considered.The governing equations are transformed into ordinary differential equations with the help of suitable similarity transformations.The Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary conditions.The integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of parameters.Graphical outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current problem.Results reveal that concentration upsurges as the micropolar parameter increases.The concentration reduces with an upsurge in the thermophoretic parameter.An upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass transport.The surface drag force declines for improved values of porosity and micropolar parameters. 展开更多
关键词 Micropolar fluid thermal radiation porous medium thermophoretic particle deposition waste discharge concentration
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Different extractable pools of Cd and Pb in agricultural soil under amendments:Water-soluble concentration sensitively indicates metal availability 被引量:1
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作者 Zidi Wang Wenyao Tang +8 位作者 Xiaodong Ding Qiang Dong Yingying Guo Guangliang Liu Yanwei Liu Yong Liang Yongguang Yin Yong Cai Guibin Jiang 《Journal of Environmental Sciences》 2025年第4期297-308,共12页
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies... Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies. 展开更多
关键词 Heavy metals Water-soluble concentrations Enriched stable isotopes Soil amendments Sequential extraction Soil pH
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Influence of Cr^(3+) Doping Concentration on the Persistent Performance of YAGG:Ce^(3+),Cr^(3+) Luminescent Ceramics
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作者 LI Tingsong WANG Wenli +4 位作者 LIU Qiang WANG Yanbin ZHOU Zhenzhen HU Chen LI Jiang 《无机材料学报》 北大核心 2025年第9期1037-1044,共8页
Y_(3)Al_(2)Ga_(3)O_(12):Ce^(3+),Cr^(3+)(YAGG:Ce^(3+),Cr^(3+)),as a persistent luminescent material,has advantages of high initial luminescence intensity and long persistent time,which is promising in persistent lumine... Y_(3)Al_(2)Ga_(3)O_(12):Ce^(3+),Cr^(3+)(YAGG:Ce^(3+),Cr^(3+)),as a persistent luminescent material,has advantages of high initial luminescence intensity and long persistent time,which is promising in persistent luminescent material applications.At present,YAGG:Ce^(3+),Cr^(3+)powders exhibit good persistent performance,but their persistent performance of ceramics still needs to be further improved to meet the new requirements.In this work,(Y_(0.998)Ce_(0.002))_(3)(Al_(1-x)Cr_(x))_(2)Ga_(3)O_(12) ceramics with different Cr^(3+)doping concentrations were prepared by solid-state reaction,including air pre-sintering,hot isostatic pressing(HIP)post-treatment and air annealing,to investigate the effects of Cr^(3+)doping concentration on the microstructure,optical properties and persistent performance of the ceramics.The results showed that as the doping concentration of Cr^(3+)increased from 0.025%to 0.2%(in atom),no significant effect of Cr^(3+)concentration on the morphology of pre-sintered ceramics or HIP post-treatment ceramics was observed,but the in-line transmittance gradually increased while the persistent performance gradually decreased.Among them,YAGG:Ce^(3+),Cr^(3+)ceramics doped with 0.025%Cr^(3+)showed the strongest initial luminescence intensity exceeding 6055 mcd/m^(2) and a persistent time of 1030 min after air pre-sintering combined with HIP post-treatment and air annealing.By optimizing the Cr^(3+)doping concentration and the fabrication process,the persistent luminescence(PersL)performance of the YAGG:Ce^(3+),Cr^(3+)ceramics was obviously improved. 展开更多
关键词 YAGG:Ce^(3+) Cr^(3+)ceramic Cr^(3+)doping concentration persistent luminescence hot isostatic pressing air annealing
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Effect of Coffee Aroma on Cerebral Activity during Concentration Tasks
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作者 Moemi Matsuo Taiyo Ichibakase +2 位作者 Hikaru Suyama Runa Takahara Takashi Higuchi 《Open Journal of Applied Sciences》 2025年第1期137-146,共10页
Caffeine has been shown to reduce various health risks, such as diabetes, obesity, and vascular diseases, and it may provide health benefits when consumed in moderate amounts, such as three to four cups per day. Howev... Caffeine has been shown to reduce various health risks, such as diabetes, obesity, and vascular diseases, and it may provide health benefits when consumed in moderate amounts, such as three to four cups per day. However, caffeine may exhibit harmful effects depending on the dose. Although the health benefits and disadvantages of caffeine intake have been studied, the effects of caffeine’s aroma have hardly been studied. This study aimed to examine the impact of caffeine scent on brain activity during cognitive tasks using electroencephalography (EEG). This study included 30 healthy young adults. We investigated cerebral activity using EEG during the concentration tasks. Participants performed tasks under pre- and post-conditions, including drinking coffee, smelling coffee, or drinking water. The number of correct responses and reaction times were calculated for each task, and mean power levels were analyzed. A linear mixed model was applied with “performance”, “ROI”, and “wave band” to examine the effects of conditions and timing. Significant differences were observed in left-frontal θ power (coffee α power (coffee P θ between pre- and post-task during water conditions (pre α on the frontal lobe and higher θ are associated with improved arousal and cognitive functions. Drinking coffee reduced α power, whereas smelling coffee or drinking water increased θ power. Therefore, drinking coffee, smelling coffee, and drinking water may affect cerebral activities and enhance cognitive performance. 展开更多
关键词 COFFEE CAFFEINE concentration ELECTROENCEPHALOGRAPHY Brain Function NEUROIMAGING
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Application of holographic laser scanning to determine the electron concentration in the plasma forming the apokamp
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作者 Anastasiia KOZHEVNIKOVA Igor ALEKSEENKO +1 位作者 Viktor TARASENKO Dmitry SCHITZ 《Plasma Science and Technology》 2025年第4期74-80,共7页
Streamer discharges that do not transition to a spark channel are now being widely investigated.One of these discharges is the apokamp discharge,in which streamers start from a diffuse spark channel having a curved sh... Streamer discharges that do not transition to a spark channel are now being widely investigated.One of these discharges is the apokamp discharge,in which streamers start from a diffuse spark channel having a curved shape at a high repetition rate of voltage pulse.In this work,to estimate the electron concentration in the plasma forming the apokamp a digital holographic laser scanning method is applied for the first time.The method is based on a comparison of the phases of two optical wavefronts,registered at different time instants in the form of digital holograms.The result of the phase comparison between the wavefronts is presented in the form of a numerically calculated map of the phase difference of the reconstructed wavefronts.A gas-discharge plasma is a phase(transparent)object,and the interference fringes are formed as a result of the change in the refractive index introduced by the plasma with respect to the original unperturbed medium.The obtained value of the refractive index allows estimation of the concentration of electrons in the spark channel plasma.It is shown that at as the voltage pulse repetition rate increases from 5 to 50 kHz the concentration of electrons in the plasma forming the apokamp decreases by an estimated four times. 展开更多
关键词 digital holography plasma diagnostics apokamp spark channel electron concentration
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Effects of Organic Materials on Enzyme Activities and Organic Carbon Concentration in Degraded Mollisol
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作者 Dai Jianjun Li Hang +2 位作者 Wang Jingyi Liu Zhaoting Wu Haifeng 《Journal of Northeast Agricultural University(English Edition)》 2025年第3期33-44,共12页
The objective of this incubation study was to comprehensively evaluate the effects of organic fertilizer and biochar,both individually and in combination,on soil respiration dynamics,key enzyme activities and the conc... The objective of this incubation study was to comprehensively evaluate the effects of organic fertilizer and biochar,both individually and in combination,on soil respiration dynamics,key enzyme activities and the concentrations of various organic carbon components in degraded mollisol.This study used a completely randomized factorial design with three application rates of organic fertilizer(M0:0,M1:13.64 g·kg^(-1),M2:27.27 g·kg^(-1))and biochar(C0:0,C1:1.36 g·kg^(-1),C2:2.73 g·kg^(-1)),resulting in nine treatments with four replicates each.Soil CO_(2) flux,organic carbon fractions including the total,active and microbial biomass carbon,and enzyme activities(sucrase,catalase and polyphenol oxidase)were measured over 120 days.Results indicated that the factors and their interactions significantly influenced all measured parameters.Soil respiration peaked at day 15,with M1C2 treatment exhibiting a rate of 10.90-fold higher than the control.The concentrations of the total,active and microbial biomass organic carbon reached maximum values on days 60,30 and 80,respectively.Notably,M2C1 treatment yielded the highest total organic carbon(86.35%increase)and microbial biomass carbon(17.84%increase).Enzyme activities were significantly enhanced,with the highest catalase activity observed for M0C2 treatment(10.14%increase).These results demonstrated that the co-application of organic fertilizer and biochar was a effective strategy for improving soil biological health and promoting carbon sequestration in degraded mollisol.The treatment combining a high rate of organic fertilizer with a low rate of biochar(M2C1)was identified as the most promising amendment strategy for fertility restoration. 展开更多
关键词 degraded mollisol soil respiration organic carbon concentration soil enzyme activity organic fertilizer BIOCHAR
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The transformation of nor-seco-cucurbit[10]uril to cucurbit[5]uril and cucurbit[8]uril controlled by its own concentration
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作者 Shaojie Deng Peihua Ma +1 位作者 Qinghong Bai Xin Xiao 《Chinese Chemical Letters》 2025年第2期345-349,共5页
Nor-seco-cucurbit[10]uril(ns-CB[10])is a kinetic product with unique structure.The single bridged methylene in its structure makes the molecular cavity of ns-CB[10]more deformable when compared to ordinary cucurbit[n]... Nor-seco-cucurbit[10]uril(ns-CB[10])is a kinetic product with unique structure.The single bridged methylene in its structure makes the molecular cavity of ns-CB[10]more deformable when compared to ordinary cucurbit[n]uril,reducing its structural stability.Repeated experiments showed that ns-CB[10]gradually cracks in an acidic solution and changes the specificity of cucurbit[5]uril(CB[5])and cucurbit[8]uril(CB[8])under more robust acidic solutions and when heated.A series of experiments were designed to study the transformation behavior of ns-CB[10].It was found that the concentration of ns-CB[10]was correlated with the content distribution of CB[5]and CB[8].This study explores the influencing factors and mechanisms of the transformation of ns-CB[10]to CB[5]and CB[8].The results are of great significance for the application of ns-CB[10],understanding the formation mechanism of cucurbit[n]urils.Furthermore,it provides a new pathway for synthesizing new cucurbit[n]urils. 展开更多
关键词 uril Cracking Transformation concentration control Mechanism
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Delayed covering causes the accumulation of motile sperm, leading to overestimation of sperm concentration and motility with a Makler counting chamber
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作者 Lin Yu Qing-Yuan Cheng +4 位作者 Ye-Lin Jia Yan Zheng Ting-Ting Yang Ying-Bi Wu Fu-Ping Li 《Asian Journal of Andrology》 2025年第1期59-64,共6页
According to the World Health Organization(WHO)manual,sperm concentration should be measured using an improved Neubauer hemocytometer,while sperm motility should be measured by manual assessment.However,in China,thous... According to the World Health Organization(WHO)manual,sperm concentration should be measured using an improved Neubauer hemocytometer,while sperm motility should be measured by manual assessment.However,in China,thousands of laboratories do not use the improved Neubauer hemocytometer or method;instead,the Makler counting chamber is one of the most widely used chambers.To study sources of error that could impact the measurement of the apparent concentration and motility of sperm using the Makler counting chamber and to verify its accuracy for clinical application,67 semen samples from patients attending the Department of Andrology,West China Second University Hospital,Sichuan University(Chengdu,China)between 13 September 2023 and 27 September 2023,were included.Compared with applying the cover glass immediately,delaying the application of the cover glass for 5 s,10 s,and 30 s resulted in average increases in the sperm concentration of 30.3%,74.1%,and 107.5%,respectively(all P<0.0001)and in the progressive motility(PR)of 17.7%,30.8%,and 39.6%,respectively(all P<0.0001).However,when the semen specimens were fixed with formaldehyde,a delay in the application of the cover glass for 5 s,10 s,and 30 s resulted in an average increase in the sperm concentration of 6.7%,10.8%,and 14.6%,respectively,compared with immediate application of the cover glass.The accumulation of motile sperm due to delays in the application of the cover glass is a significant source of error with the Makler counting chamber and should be avoided. 展开更多
关键词 concentration improved Neubauer hemocytometer Makler counting chamber MOTILITY SPERM
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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent
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作者 H.HOSSEINI O.BALILASHAKI 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期139-156,共18页
The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically.It is assu... The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically.It is assumed that the source is located outside the cavity at a specified distance from the borehole axis.The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed.Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid,empty borehole,and rigid inclusion with a hard boundary is employed for the analysis.Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions,the proposed boundary conditions at the interface are satisfied.Stresses are formulated by means of wave potential functions in a three-dimensional(3D)manner.The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra.Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis.To give an overall outline of the study,a numerical example is presented.The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values.In addition,the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole.Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases,and good agreement is achieved. 展开更多
关键词 point source cylindrical cavity porous medium wave-field transformation stress concentration
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Design and test of cesium atomic concentration detection system based on TDLAS
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作者 LIANG Lizhen LIU Shanhu +2 位作者 WU Yong WEI Jianglong XIE Yahong 《Optoelectronics Letters》 2025年第3期167-171,共5页
In order to better build the neutral beam injector with negative ion source(NNBI),the pre-research on key technologies has been carried out for the comprehensive research facility for fusion technology(CRFFT).Cesium s... In order to better build the neutral beam injector with negative ion source(NNBI),the pre-research on key technologies has been carried out for the comprehensive research facility for fusion technology(CRFFT).Cesium seeding into negative-ion sources is a prerequisite to obtain the required negative hydrogen ion.The performance of ion source largely depends on the cesium conditions in the source.It is very necessary to quantitatively measure the amount of cesium in the source during the plasma on and off periods(vacuum stage). 展开更多
关键词 atomic concentration tdlas CESIUM detection system ion source negative hydrogen ionthe negative ion source nnbi neutral beam injector
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PM_(2.5)-bound metallic elements in village and urban airs in North China during wintertime:Concentration,morphology,mixing state,and size distribution
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作者 Yinxiao Zhang Jian Zhang +3 位作者 Xiaotong Jiang Yuanyuan Wang Xiaokun Ding Weijun Li 《Journal of Environmental Sciences》 2025年第12期724-734,共11页
Atmospheric metal pollution is a significant environmental issue in China.Understanding the microscopic characteristics of metallic elements are crucial for investigating their sources and health effects,but this info... Atmospheric metal pollution is a significant environmental issue in China.Understanding the microscopic characteristics of metallic elements are crucial for investigating their sources and health effects,but this information is still limited.In this study,transmission electron microscopy(TEM)combined with bulk analysis method were employed to investigate the microscopic characteristics and mass concentrations of atmospheric metallic elements at a village site and an urban site located in North China Plain during wintertime.Our results reveal that the total mass concentrations of 16 metallic elements(including nine toxic heavy metallic elements)in PM_(2.5)were 3439.18±1101.24 ng/m^(3)(1129.6±376.85 ng/m^(3))at the village site and 3555.1±916.71 ng/m^(3)(1295.26±446.39 ng/m^(3))at urban site,accounting for 2.23%and 2.76%of PM_(2.5),respectively.We found that K,Ca,and Fe were the dominant elements,constituting over 75%of total metal mass.TEM analysis indicates that these metallic elements were mainly enriched in six types of individual particles,including K-rich,mineral,fly ash,Fe-rich,Zn-rich,and Pb-rich particles.Mineral particles were predominant in all individual metal particles at urban site,while K-rich particles became the dominant metal particles influenced by residential biomass burning at village site.Moreover,we found toxic metal particles(Fe-rich,Zn-rich,Pb-rich,and fly ash)presented smaller mean sizes(243 nm)in village air compared to urban air(337 nm),suggesting that metal particles in village air might pose a higher health risk to the residents.These results emphasize that atmospheric metal pollution in the village areas need more attentions in the future. 展开更多
关键词 Metallic elements Individual particles Village air Mass concentration Microscopic characteristics
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Thermal stress concentration points and stress mutations in nano-multilayer film structures
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作者 Ying Zheng Zhi You Wang +6 位作者 Qianju Song Zao Yi Shubo Cheng Can Ma Chaojun Tang Qingdong Zeng Sohail Ahmad 《Communications in Theoretical Physics》 2025年第1期179-189,共11页
In the multilayer film-substrate system,thermal stress concentration and stress mutations cause film buckling,delamination and cracking,leading to device failure.In this paper,we investigated a multilayer film system ... In the multilayer film-substrate system,thermal stress concentration and stress mutations cause film buckling,delamination and cracking,leading to device failure.In this paper,we investigated a multilayer film system composed of a substrate and three film layers.The thermal stress distribution inside the structure was calculated by the finite element method,revealing significant thermal stress differences between the layers.This is mainly due to the mismatch of the coefficient of thermal expansion between materials.Different materials respond differently to changes in external temperature,leading to compression between layers.There are obvious thermal stress concentration points at the corners of the base layer and the transition layer,which is due to the sudden change of the shape at the geometric section of the structure,resulting in a sudden increase in local stress.To address this issue,we chamfered the substrate and added an intermediate layer between the substrate and the transition layer to assess whether these modifications could reduce or eliminate the thermal stress concentration points and extend the service life of the multilayer structure.The results indicate that chamfering and adding the intermediate layer effectively reduce stress discontinuities and mitigate thermal stress concentration points,thereby improving interlayer bonding strength. 展开更多
关键词 multilayer structure thermal stress concentration point stress mutation CHAMFER intermediate layer
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Significance of monitoring imatinib plasma concentration in secondline treatment decisions for c-kit 11 gene-mutated gastrointestinal stromal tumors
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作者 Hai-Tao Li Yun-Yun Du +2 位作者 Zhen Huang Jin-Jin Li Jun Zhang 《World Journal of Gastrointestinal Oncology》 2025年第3期81-90,共10页
BACKGROUND For patients with advanced gastrointestinal stromal tumors(GISTs)carrying the ckit exon 11 mutation,imatinib(IM)at a standard dosage of 400 mg per day is the preferred first-line treatment.In cases where tr... BACKGROUND For patients with advanced gastrointestinal stromal tumors(GISTs)carrying the ckit exon 11 mutation,imatinib(IM)at a standard dosage of 400 mg per day is the preferred first-line treatment.In cases where treatment with IM fails,there is an urgent need for a more precise assessment method to determine whether to switch therapies or escalate the IM dosage.This approach will enhance clinical decision-making and optimize patient outcomes.AIM To investigate IM plasma concentration’s role in second-line treatment decisions for c-kit 11-mutated advanced GISTs post-IM failure.METHODS Patients with advanced GIST harboring c-kit 11 mutation who experienced failure with IM 400 mg per day as first-line treatment at our hospital were retrospectively analyzed.Patients were categorized into a low plasma(LP)concentration group(LP group,<1100 ng/mL)and high plasma(HP)concentration group(HP group,≥1100 ng/mL).Each group was further subdivided into Group A(dose-escalation group)and Group B(drug-switch group).Baseline characteristics were compared and Kaplan-Meier curves were used to analyze the survival of patients.RESULTS Seventy-five patients were included in the analysis.For the LP group(n=28),Group A(n=14)had longer overall survival(OS)than Group B(n=14)(P=0.02).No differences were observed between the two subgroups in disease control rate(DCR),objective response rate,and progression-free survival(PFS)(P>0.05).For the HP group(n=47),Group B(n=18)had a higher DCR and longer PFS than Group A(n=29)(P=0.008 and P=0.03,respectively).No difference in OS was observed between the two subgroups(P>0.05).CONCLUSION Increasing IM dosage for c-kit 11-mutated advanced GISTs post-IM failure may prolong OS if plasma concentration is<1100 ng/mL.Switching tyrosine kinase inhibitors may improve DCR and PFS if≥1100 ng/mL. 展开更多
关键词 Gastrointestinal stromal tumor C-kit exon 11 IMATINIB Plasma concentration Second-line treatment
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ON THE MEASURE CONCENTRATION OF INFINITELY DIVISIBLE DISTRIBUTIONS
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作者 Jing ZHANG Zechun HU Wei SUN 《Acta Mathematica Scientia》 2025年第2期473-492,共20页
Let I be the set of all infinitely divisible random variables with finite second moments,I_(0)={X∈I;Var(X)>0},P_(I)=inf_(x∈I)P{|X-E[X]|≤√Var(X)}and P_(I_(0))=inf P{|X-E[X]|<√Var(X)}.Firstly,we prove that P_... Let I be the set of all infinitely divisible random variables with finite second moments,I_(0)={X∈I;Var(X)>0},P_(I)=inf_(x∈I)P{|X-E[X]|≤√Var(X)}and P_(I_(0))=inf P{|X-E[X]|<√Var(X)}.Firstly,we prove that P_(I)≥P_(I_(0))>0.Secondly,we find_(x∈I_(0))the exact values of inf P{|X-E[X]|≤√Var(X)}and inf P{|X-E[X]|<√Var(X)}for the cases that J is the set of all geometric random variables,symmetric geometric random variables,Poisson random variables and symmetric Poisson random variables,respectively.As a consequence,we obtain that P_(I)≤e^(-1)^(∞)∑_(k=0)1/2^(2k)(k!)^(2)≈0.46576 and P_(I_(0))≤e^(-1)≈0.36788. 展开更多
关键词 measure concentration infinitely divisible distribution geometric distribution Poisson distribution Berry-Esseen theorem
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Commentary on“Delayed covering causes the accumulation of motile sperm,leading to overestimation of sperm concentration and motility with a Makler counting chamber”
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作者 Elisabetta Tosti 《Asian Journal of Andrology》 2025年第1期135-136,共2页
The analysis of the ejaculate,better known as spermiogram,represents the first and main step to identify whether a series of sperm quality parameters are within the norm and therefore are consistent with normal sperm ... The analysis of the ejaculate,better known as spermiogram,represents the first and main step to identify whether a series of sperm quality parameters are within the norm and therefore are consistent with normal sperm fertilizing capacity.Among these,sperm concentration and motility are the first parameters to be evaluated through an estimation carried out by expert examiners. 展开更多
关键词 identify whether series sperm quality parameters within delayed covering accumulation MOTILITY OVERESTIMATION makler counting chamber motile sperm sperm concentration
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An effective approach for correlating Na^(+) concentrations with sweating rates in wearable sweat sensing platform
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作者 Anwei He Xiaohe Wang +6 位作者 Liang Zhang Haolong Zhang Xingli Xu Chenyang Yu Yongquan Ma Wei Wei Pengfei Niu 《Nanotechnology and Precision Engineering》 2025年第1期58-67,共10页
Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat se... Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat sensing platforms.However,concentration measurements of biomarkers are always delayed on the timeline compared with their production,whereas there is no such delay for sweating rate.Thus,a timeline mismatch exists between these two measurements.This means that the concentration vs rate correlation constructed on the basis of such measurements will deviate from the actual correlation.This study demonstrates the existence of this mismatch and explains its cause using sweat Na^(+)measurements.It also proposes an effective approach that applies a point-by-point compensation for the delay between Na+measurements and the real-time sweating rates,such that the data on the repositioned concentration vs time curve correspond to exactly the same point on the timeline as their production.A vison sensor is developed to measure the sweating rate with high accuracy at a frequency of more than 0.1 Hz.Off-body and on-body measurements of sweating rate and Na^(+)concentration are carried out,and concentration–rate correlations are constructed using both measured and repositioned concentration curves.The least squares and random forest methods are employed to fit the constructed correlations and evaluate the reliability of the proposed approach.The use of the repositioned concentration curve gives a constructed correlation that is much closer to the actual one.This study indicates the necessity to rearrange sensor-measured biomarker concentration vs time curves when correlations of concentration with sweating rate need to be constructed and proposes a practical point-by-point data repositioning strategy for doing so.The results presented here will benefit the study of sweat biomarkers with unclear correlations with sweating rate,as well as providing a basis for the development of more reliable sweat-based diagnostic methods. 展开更多
关键词 Wearable sweat monitoring Sweating rate concentration rate correlation Timeline mismatch Machine learning
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Ultrahigh concentration of NV^(−)centers embedded in the CVD epi-diamond layer near the interface with an HPHT diamond substrate
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作者 Yuanjie Yang Shengran Lin +4 位作者 Jiaxin Zhao Changfeng Weng Liren Lou Wei Zhu Guanzhong Wang 《Chinese Physics B》 2025年第5期498-503,共6页
The negatively charged nitrogen vacancy(NV^(−))center ensemble in as-grown chemical vapor deposition(CVD)diamond is a promising candidate for quantum sensing due to its long coherence time and excellent optical proper... The negatively charged nitrogen vacancy(NV^(−))center ensemble in as-grown chemical vapor deposition(CVD)diamond is a promising candidate for quantum sensing due to its long coherence time and excellent optical properties.However,achieving a high concentration of NV^(−)centers in as-grown CVD diamond remains a critical challenge,which constrains the performance of NV^(−)based sensors.In this study,we observe that NV^(−)center formation efficiency is significantly enhanced during the initial growth phase,with a coherence time T_(2)^(*)of 1.1μs.These findings demonstrate that high-concentration NV^(−)centers can be achieved in as-grown diamonds,greatly enhancing their utility in high-performance magnetometers and quantum sensing. 展开更多
关键词 INTERFACE high concentration nitrogen vacancy centers chemical vapor deposition(CVD) DIAMOND
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