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1EMT-associated microRNAs and their roles in cancer stemness and drug resistance显示文摘Epithelial-to-mesenchymal transition(EMT)is implicated in a wide array of malignant behaviors of cancers,including proliferation,invasion,and metastasis.Most notably,previou studies have indicated that both cancer stem-like properties and drug resistance were associated with EMT.Furthermore,microRNAs(miRNAs)play a pivotal role in the regulation of EMT phenotype,as a result,some miRNAs impact cancer stemness and drug resistance.Therefore,understanding the relationship between EMT-associated miRNAs and cancer stemness/drug resistance is beneficial to both basic research and clinical treatment.In this review,we preliminarily looked into the various roles that the EMT-associated miRNAs play in the stem-like nature of malignant cells.Then,we reviewed the interaction between EMT-associated miRNAs and the drugresistant complex signaling pathways of multiple cancers including lung cancer,gastric cancer,gynecologic cancer,breast cancer,liver cancer,colorectal cancer,pancreatic cancer,esophageal cancer,and nasopharyngeal cancer.We finally discussed the relationship between EMT,cancer stemness,and drug resistance,as well as looked forward to the potential applications of miRNA therapy for malignant tumors.Guangtao Pan Yuhan Liu Luorui Shang Fangyuan Zhou Shenglan Yang 2021Cancer Communications2021,41,3:46
2Explicit diagnosis of the local ozone production rate and the ozone-NOx-VOC sensitivities显示文摘In the troposphere, ozone is a harmful gas compound to both human health and vegetation. Ozone is produced from the reaction of NO_x(@NO + NO_2) and VOCs(volatile organic compounds) with light. Due to the highly nonlinear relationships between ozone and its precursors, proper ozone mitigation relies on the knowledge of chemical mechanisms. In this study, an observation-based method is used to simulate ozone formation and elucidate its controlling factors for a rural site on the North China Plain. The instantaneous ozone production rate is calculated utilizing a box model using the dataset obtained from the Wangdu campaign. First, the model was operated in a time-dependent mode to calculate the ozone production rate at each time stamp. The calculated ozone formation rate showed a diurnal average maximum value of 17 ppbv/h(1-h diurnal averaged). The contribution of individual peroxy radicals to ozone production was analyzed. In addition, the functional dependence of calculated P(O_3) reveals that ozone production was in a NO_x-limited regime during the campaign. Furthermore, the missing peroxy radical source will further extend NO_x-limited conditions to earlier in the day, making NO_xlimitation dominate more of a day than the current chemical model predicts. Finally, a multiple scenarios mode,also known as EKMA(empirical kinetic modeling approach), was used to simulate the response of P(O_3) to the imaginary change in precursor concentrations. We found that ozone production was in the NO_x-limited region. However, the use of NO_2 measured by the molybdenum converter and/or the absence of a peroxy radical source in the current chemical model could over-emphasize the VOC-limited effect on ozone production.Zhaofeng Tan Keding Lu Huabin Dong Min Hu Xin Li Yuhan Liu Sihua Lu Min Shao Rong Su Haichao Wang Yusheng Wu Andreas Wahner Yuanhang Zhang 2018Science Bulletin2018,63,16:25
3Exploring atmospheric free-radical chemistry in China:the self-cleansing capacity and the formation of secondary air pollution显示文摘Since 1971,it has been known that the atmospheric free radicals play a pivotal role in maintaining the oxidizing power of the troposphere.The existence of the oxidizing power is an important feature of the troposphere to remove primary air pollutants emitted from human beings as well as those from the biosphere.Nevertheless,serious secondary air-pollution incidents can take place due to fast oxidation of the primary pollutants.Elucidating the atmospheric free-radical chemistry is a demanding task in the field of atmospheric chemistry worldwide,which includes two kinds of work:first,the setup of reliable radical detection systems;second,integrated field studies that enable closure studies on the sources and sinks of targeted radicals such as OH and NO3.In this review,we try to review the Chinese efforts to explore the atmospheric free-radical chemistry in such chemical complex environments and the possible link of this fast gas-phase oxidation with the fast formation of secondary air pollution in the city-cluster areas in China.Keding Lu Song Guo Zhaofeng Tan Haichao Wang Dongjie Shang Yuhan Liu Xin Li Zhijun Wu Min Hu Yuanhang Zhang 2019National Science Review2019,6,3:26
4The regulation of MDM2 oncogene and its impact on human cancers显示文摘肿瘤 suppressor p53 在阻止肿瘤形成起一个中央作用。p53 的层次和活动在紧密的 regulationto 下面保证它的合适的功能。鼠科的双分钟 2 (MDM2 ) , p53 目标基因,是 E3 ubiquitin ligase。MDM2 是 p53 蛋白质的一个 keynegative 管理者,并且与 p53 形成一个自动调整的反馈环。MDM2 是有两 p53-dependentand 的 oncogene p53 独立的 oncogenic 活动,并且经常在许多人的癌症增加了表示层次。ishighly 调整的 MDM2;MDM2 的层次和功能在 transcriptional 被调整,翻译并且 post-translationallevels。这评论提供 MDM2 的规定的概述。MDM2 的 Dysregulation 在 p53functions 之上显著地影响,并且接着 tumorigenesis。就 MDM2 在人的癌症起的关键作用而言,更好的 understandingof MDM2 的规定将帮助我们得新奇、更有效的癌症在房间指向 MDM2 andactivate p53 的治疗学的策略。Yuhan Zhao Haiyang Yu Wenwei Hu 2014Acta Biochimica et Biophysica Sinica2014,46,3:18
5Wholly smoothing cutter orientations for five-axis NC machining based on cutter contact point mesh显示文摘Cutting forces with respect to different cutter orientations are analyzed for five-axis NC machining of a ball-end cutter.A measure is then defined to quantify the effects of cutter orientation variation.According to the measure,a novel model and algorithm are proposed to wholly optimize cutter orientations based on a cutter contact(CC) point mesh.The method has two advantages.One is that the cutter orientation smoothnesses along the feed direction and pick-feed direction are both wholly optimized.The other is that only the accessibility cones of mesh points are required to compute and the computation efficiency is improved.These advantages are shown by simulating the machining efficiency,the stability of feed velocities and the smoothness of cutting force.A computational example and a cutting experiment are finally given to illustrate the validity of the proposed method.BI QingZhen,WANG YuHan,ZHU LiMin & DING Han State Key Laboratory of Mechanical System and Vibration,School of Mechanical Engineering,Shanghai Jiaotong University,Shanghai 200240,China 2010Science China(Technological Sciences)2010,53,5:12
6Meningeal lymphatic vessels regulate brain tumor drainage and immunity显示文摘Recent studies have shown that meningeal lymphatic vessels(MLVs),which are located both dorsally and basally beneath the skull,provide a route for draining macromolecules and trafficking immune cells from the central nervous system(CNS)into cervical lymph nodes(CLNs),and thus represent a potential therapeutic target for treating neurodegenerative and neuroinflammatory diseases.However,the roles of MLVs in brain tumor drainage and immunity remain unexplored.Here we show that dorsal MLVs undergo extensive remodeling in mice with intracranial gliomas or metastatic melanomas.RNA-seq analysis of MLV endothelial cells revealed changes in the gene sets involved in lymphatic remodeling,fluid drainage,as well as inflammatory and immunological responses.Disruption of dorsal MLVs alone impaired intratumor fluid drainage and the dissemination of brain tumor cells to deep CLNs(dCLNs).Notably,the dendritic cell(DC)trafficking from intracranial tumor tissues to dCLNs decreased in mice with defective dorsal MLVs,and increased in mice with enhanced dorsal meningeal lymphangiogenesis.Strikingly,disruption of dorsal MLVs alone,without affecting basal MLVs or nasal LVs,significantly reduced the efficacy of combined anti-PD-1/CTLA-4 checkpoint therapy in striatal tumor models.Furthermore,mice bearing tumors overexpressing VEGF-C displayed a better response to anti-PD-1/CTLA-4 combination therapy,and this was abolished by CCL21/CCR7 blockade,suggesting that VEGF-C potentiates checkpoint therapy via the CCL21/CCR7 pathway.Together,the results of our study not only demonstrate the functional aspects of MLVs as classic lymphatic vasculature,but also highlight that they are essential in generating an efficient immune response against brain tumors.Xueting Hu Qiuping Deng Lu Ma Qingqing Li Yidong Chen Yuhan Liao Fan Zhou Chen Zhang Linlin Shao Jun Feng Tubao He Weihai Ning Yan Kong Yingqing Huo Aibin He Bing Liu Jingjing Zhang Ralf Adams Yulong He Fuchou Tang Xiuwu Bian Jincai Luo 2020Cell Research2020,30,3:11
7The study on the safety and efficacy of amnion graft for preventing the recurrence of moderate to severe intrauterine adhesions显示文摘Transcervical resection of adhesion(TCRA)is the standard treatment for the intrauterine adhesions,but the recurrence of adhesions is a tough problem for the gynecologist.In addition,the therapeutic strategy after TCRA about prevention of recurrence remains controversial especially for the patients with moderate to severe intrauterine adhesions(IUAs).Hence,we designed this study to explore the safety and efficacy of fresh amnion grafts for preventing the recurrence after TCRA for patients with moderate to severe IUAs.One hundred patients with moderate to severe IUAs who presented with a history of hypomenorrhea,amenorrhea and infertility were included in the study from January 2015 to December 2017.Patients were divided into amnion group(52 patients)and chitosan group(48 patients).Fresh amnion grafts or intrauterine injections of chitosan were administered after TCRA.Transvaginal ultrasonography(TVUS)and hysteroscopy were performed at the first and third month after the operation.The surgical procedures for all patients were completed successfully without relevant complications.In amnion group,8 patients exhibited relapse in the first month and 2 patients in three months after surgery;in chitosan group,23 women exhibited relapse in the first month and 18 patients in three months after surgery.Statistical analysis revealed that the recurrence rate of adhesion in amnion group was significantly lower than those of chitosan group in the first and three months after surgery(P1=0.000,P2=0.000).After TCRA,fresh amnion graft plays a significant role in preventing further adhesions than injections of chitosan.Changjiang Li Aiqi Cai Congcong Sun Benyuan Wu Xinpei Chen Yanhua Mao Yingfeng Zhang Yating Gou Jie Yu Yuhan Wang Huanhuan Yu Jia Wang 2020Genes & Diseases2020,7,2:11
8The Cenozoic activities of Yangjiang-Yitongdong Fault: insights from analysis of the tectonic characteristics and evolution processes in western Zhujiang(Pearl) River Mouth Basin显示文摘The Yangjiang-Yitongdong Fault (YJF) is an important NW-trending regional fault, which divides the Zhujiang (Pearl) River Mouth Basin (ZRMB) into western and eastern segments. In Cenozoic, the northern continental margin of the South China Sea (SCS) underwent continental rifting, breakup, seafloor spreading and thermal subsidence processes, and the Cenozoic activities of YJF is one part of this series of complex processes. Two long NW-trending multichannel seismic profiles located on both sides of the YJF extending from the continental shelf to Continent-Ocean Boundary (COB) were used to study the tectonic and sedimentary characteristics of western ZRMB. Using the 2D-Move software and back-stripping method, we constructed the balance cross-section model and calculated the fault activity rate. Through the comprehensive consideration of tectonic position, tectonic evolution history, featured structure, and stress analysis, we deduced the activity history of the YJF in Cenozoic. The results showed that the YJF can be divided into two segments by the central uplift belt. From 65 Ma to 32 Ma, the YJF was in sinistral motion as a whole, inherited the preexisting sinistral motion of Mesozoic YJF, in which, the southern part of YJF was mainly in extension activity, controlling the formation and evolution of Yunkai Low Uplift, coupled with slight sinistral motion. From 32 Ma to 23.8 Ma, the sinistral motion in northern part of YJF continued, while the sinistral motion in southern part began to stop or shifted to a slightly dextral motion. After 23.8 Ma, the dextral motion in southern part of YJF continued, while the sinistral motion in northern part of YJF gradually stopped, or shifted to the slightly dextral motion. The shift of the YJF strike-slip direction may be related to the magmatic underplating in continent-ocean transition, southeastern ZRMB. According to the analysis of tectonic activity intensity and rift sedimentary structure, the activities of YJF in Cenozoic played a regulating role in the rift extension process of ZRMB.Yuhan Li Rongwei Zhu Hailing Liu Xuelin Qiu Haibo Huang 2019Acta Oceanologica Sinica2019,38,9:10
9Higher alcohol synthesis over Cu-Fe composite oxides with high selectivity to C_(2+)OH显示文摘Cu-Fe composite oxides were prepared by co-precipitation method and tested for higher alcohol synthesis from syngas. The selectivity to C2+OH and C6+OH in alcohol distribution was very high while the methane product fraction in hydrocarbon distribution was rather low, demonstrating a promising potential in higher alcohols synthesis from syngas. The distribution of alcohols and hydrocarbons approximately obeyed Anderson-Schulz-Flory distribution with similar chain growth probability, indicating alcohols and hydrocarbons derived from the same intermediates. The effects of Cu/Fe molar ratio, reaction temperature and gas hourly space velocity (GHSV) on catalytic performance were studied in detail. The sample with a Cu/Fe molar ratio of 10/1 exhibited the best catalytic performance. Higher reaction temperature accelerated water-gas-shift reaction and led to lower total alcohols selectivity. GHSV showed great effect on catalytic performance and higher GHSV increased the total alcohol selectivity, indicating there existed visible dehydration reaction of alcohol into hydrocarbon.Zhenghong Bao Kang Xiao Xingzhen Qi Xinxing Wang Liangshu Zhong Kegong Fang Minggui Lin Yuhan Sun 2013Journal of Energy Chemistry2013,22,1:10
10Dynamic soft sensor development based on Gaussian mixture regression for fermentation processes显示文摘The dynamic soft sensor based on a single Gaussian process regression(GPR) model has been developed in fermentation processes.However,limitations of single regression models,for multiphase/multimode fermentation processes,may result in large prediction errors and complexity of the soft sensor.Therefore,a dynamic soft sensor based on Gaussian mixture regression(GMR) was proposed to overcome the problems.Two structure parameters,the number of Gaussian components and the order of the model,are crucial to the soft sensor model.To achieve a simple and effective soft sensor,an iterative strategy was proposed to optimize the two structure parameters synchronously.For the aim of comparisons,the proposed dynamic GMR soft sensor and the existing dynamic GPR soft sensor were both investigated to estimate biomass concentration in a Penicillin simulation process and an industrial Erythromycin fermentation process.Results show that the proposed dynamic GMR soft sensor has higher prediction accuracy and is more suitable for dynamic multiphase/multimode fermentation processes.Congli Mei Yong Su Guohai Liu Yuhan Ding Zhiling Liao 2017Chinese Journal of Chemical Engineering2017,25,1:8
11Advances in direct production of value-added chemicals via syngas conversion显示文摘Syngas conversion to fuels and chemicals is one of the most challenging subjects in the field of C1 chemistry. It is considered as an attractive alternative non-petroleum-based production route. The direct synthesis of olefins and alcohols as high value-added chemicals from syngas has drawn particular attention due to its process simplicity, low energy consumption and clean utilization of carbon resource, which conforms to the principles of green carbon science. This review describes the recent advances for the direct production of lower olefins and higher alcohols via syngas conversion. Recent progress in the development of new catalyst systems for enhanced catalytic performance is highlighted. We also give recommendations regarding major challenges for further research in syngas conversion to various chemicals.Yunlei An Tiejun Lin Fei Yu Yanzhang Yang Liangshu Zhong Minghong Wu Yuhan Sun 2017Science China Chemistry2017,60,7:8
12Performance of integrated optical switches based on 2D materials and beyond显示文摘Applications of optical switches,such as signal routing and data-intensive computing,are critical in optical interconnects and optical computing.Integrated optical switches enabled by two-dimensional(2D)materials and beyond,such as graphene and black phosphorus,have demonstrated many advantages in terms of speed and energy consumption compared to their conventional silicon-based counterparts.Here we review the state-of-the-art of optical switches enabled by 2D materials and beyond and organize them into several tables.The performance tables and future projections show the frontiers of optical switches fabricated from 2D materials and beyond,providing researchers with an overview of this field and enabling them to identify existing challenges and predict promising research directions.Yuhan YAO Zhao CHENG Jianji DONG Xinliang ZHANG 2020Frontiers of Optoelectronics2020,13,2:8
13Highly enhanced visible-light photocatalytic NOx purification and conversion pathway on self-structurally modified g-C-3N4 nanosheets显示文摘The unmodified graphitic carbon nitride(g-C_3N_4) suffers from low photocatalytic activity because of the unfavourable structure.In the present work,we reported a simple self-structural modification strategy to optimize the microstructure of g-C_3N_4 and obtained graphene-like g-C_3N_4 nanosheets with porous structure.In contrast to traditional thermal pyrolysis preparation of g-C_3N_4,the present thermal condensation was improved via pyrolysis of thiourea in an alumina crucible without a cover,followed by secondary heat treatment.The popcorn-like formation and layer-by-layer thermal exfoliation of graphene-like porous g-C_3N_4 was proposed to explain the formation mechanism.The photocatalytic removal performance of both NO and NO_2 with the graphene-like porous g-C_3N_4 for was significantly enhanced by selfstructural modification.Trapping experiments and in-situ diffuse reflectance infrared fourier transform spectroscopy(DRIFTS) measurement were conducted to detect the active species during photocatalysis and the conversion pathway of g-C_3N_4 photocatalysis for NO_x purification was revealed.The photocatalytic activity of graphene-like porous g-C_3N_4 was highly enhanced due to the improved charge separation and increased oxidation capacity of the ·O_2^- radicals and holes.This work could not only provide a novel self-structural modification for design of highly efficient photocatalysts,but also offer new insights into the mechanistic understanding of g-C_3N_4 photocatalysis.Yuhan Li Yanjuan Sun Wingkei Ho Yuxin Zhang Hongwei Huang Qiang Cai Fan Dong 2018Science Bulletin2018,63,10:7
14Synthesis of mesoporous polymeric carbon nitride exhibiting enhanced and durable visible light photocatalytic performance显示文摘A thiourea precursor was employed to synthesize mesoporous carbon nitride(C3 N4) by a thermal polycondensation process with high surface area SiO2 and nanosphere SiO2 as two types of hard templates. The resultant mesoporous C3 N4 samples have high surface areas(105–112 m2/g) and mesopores with narrow sizes distribution(9.3 nm). Photocatalytic performance was evaluated by removal of NO in air under visible light irradiation. The results showed that mesoporous C3 N4 samples exhibited significantly improved photocatalytic activity in comparison with bulk C3 N4, which also exceeded that of N-doped TiO2 and C-doped TiO2. The activity enhancement can be ascribed to the synergistic effects of large surface area and pore volume, enhanced light-harvesting ability, increased redox potential, and reduced recombination of charge carriers. In addition to the high activity, the mesoporous C3 N4 samples also showed high photochemical stability. The mesoporous C3 N4 photocatalysts with enhanced and durable activity could provide a new efficient material for environmental pollution control.Fan Dong Yuhan Li Wingkei Ho Haidong Zhang Min Fu Zhongbiao Wu 2014Chinese Science Bulletin2014,59,7:7
15A Review of Technical Advances,Barriers,and Solutions in the Power to Hydrogen(P2H)Roadmap显示文摘Power to hydrogen(P2H)provides a promising solution to the geographic mismatch between sources of renewable energy and the market,due to its technological maturity,flexibility,and the availability of technical and economic data from a range of active demonstration projects.In this review,we aim to provide an overview of the status of P2H,analyze its technical barriers and solutions,and propose potential opportunities for future research and industrial demonstrations.We specifically focus on the transport of hydrogen via natural gas pipeline networks and end-user purification.Strong evidence shows that an addition of about 10%hydrogen into natural gas pipelines has negligible effects on the pipelines and utilization appliances,and may therefore extend the asset value of the pipelines after natural gas is depleted.To obtain pure hydrogen from hydrogen-enriched natural gas(HENG)mixtures,end-user separation is inevitable,and can be achieved through membranes,adsorption,and other promising separation technologies.However,novel materials with high selectivity and capacity will be the key to the development of industrial processes,and an integrated membrane-adsorption process may be considered in order to produce high-purity hydrogen from HENG.It is also worth investigating the feasibility of electrochemical separation(hydrogen pumping)at a large scale and its energy analysis.Cryogenics may only be feasible when liquefied natural gas(LNG)is one of the major products.A range of other technological and operational barriers and opportunities,such as water availability,byproduct(oxygen)utilization,and environmental impacts,are also discussed.This review will advance readers’understanding of P2H and foster the development of the hydrogen economy.Guoping Hu Chao Chen Hiep Thuan Lu Yue Wu Congmin Liu Lefu Tao Yuhan Men Guangli He Kevin Gang Li 2020Engineering2020,6,12:7
16CKIP-1 regulates macrophage proliferation by inhibiting TRAF6-mediated Akt activation显示文摘巨噬细胞在开发,动态平衡,织物修理和免疫起枢轴的作用。巨噬细胞增长被刺激殖民地的因素(M-CSF ) 导致了 Akt 发信号的巨噬细胞支持;然而,这个过程怎么被终止,仍然保持不清楚。这里,我们作为巨噬细胞增长的一个新奇禁止者识别酷蛋白 kinase 2-interacting protein-1 (CKIP-1 ) 。在放松巨噬细胞, CKIP-1 是在由组成地活跃的 GSK3β 的丝氨酸 342 点的 phosphorylated;, Akt 的下游的目标。这 phosphorylation 触发 CKIP-1 的 polyubiquitination 和 proteasomal 降级。在 M-CSF 刺激之上, Akt 被 CSF-1R-PI3K 激活然后使 GSK3β 失去活性;,导致 CKIP-1 和 β 的稳定; -catenin 蛋白质。β -catenin 包括 cyclin D 和 c-Myc 支持增长基因的表示。CKIP-1 与 TRAF6,为连接 K63 的 ubiquitination 要求的 ubiquitin ligase 和 Akt 的血浆膜招募交往,并且终止调停 TRAF6 的 Akt 激活。由这个工具, CKIP-1 在 M-CSF 刺激以后在迟了的阶段明确地禁止巨噬细胞增长。而且, CKIP-1 缺乏在老鼠自发地开发的 vitro 和 CKIP-1 −/− 导致增加的增长和巨噬细胞的减少的 apoptosis 巨噬细胞主导的脾大和 myeloproliferation。一起,这些数据证明 CKIP-1 由禁止调停 TRAF6 的 Akt 激活在巨噬细胞动态平衡的规定起一个关键作用。Luo Zhang Yiwu Wang Fengjun Xiao Shaoxia Wang Guichun Xing Yang Li Xiushan Yin Kefeng Lu Rongfei Wei Jiao Fan Yuhan Chen Tao Li Ping Xie Lin Yuan Lei Song Lanzhi Ma Lujing Ding Fuchu He Lingqiang Zhang 2014Cell Research2014,24,6:7
17Management of CO_(2) in a tomato greenhouse using WSN and BPNN techniques显示文摘Rational management of CO_(2) can improve the net photosynthetic rate of plants,thereby improving crop yield and quality.In order to precisely manage CO_(2) in a greenhouse,a wireless sensor network(WSN)system was developed to monitor greenhouse environmental parameters in real time,including air temperature,humidity,CO_(2) concentration,soil temperature,soil moisture,and light intensity.The WSN system includes several sensor nodes,a gateway node,and remote management software.The sensor nodes can collect 0-5 V and 4-20 mA analog signals and universal asynchronous receiver/transmitter(UART)data.The gateway node can process and transmit the data and commands between sensor nodes and remote management software.The remote management software provides a friendly interface between user and machine.Users can inquire about real-time data,and set the parameters of the WSN.The photosynthetic rate of tomato plants were studied in the flowering stage.A LI-6400XT portable photosynthesis analyzer was used to measure the photosynthetic rates of the tomato plants,and the environmental parameters of leaves were controlled according to the presetting rule.The photosynthetic rate prediction model of a single leaf was established based on a back propagation neural network(BPNN).The environmental parameters were used as input neurons after being processed by principal component analysis(PCA),and the photosynthetic rate was taken as the output neuron.The performance of the prediction model was evaluated,and the results showed that the correlation coefficient between the simulated and observed data sets was 0.9899,and root-mean-square error(RMSE)was 1.4686.Furthermore,when different CO_(2) concentrations were selected as the input to predict the photosynthetic rate,the simulated and observed data showed the same trend.According to the above analysis,it was concluded that the model can be used for quantitative regulation of CO_(2) for tomato plants in greenhouses.Li Ting Zhang Man Ji Yuhan Sha Sha Jiang Yiqiong Li Minzan 2015International Journal of Agricultural and Biological Engineering2015,8,4:6
18Controlled growth of silver nanoparticles in a hydrothermal process显示文摘A two-step synthesis was used to control the shape of silver nanoparticles. First, a few spherical silver nanoparticles, ~10nm in size, were prepared via reduction of Ag+ ions in aqueous Ag(NH3)2NO3 by poly(N-vinyl-2-pyrrolidone) (PVP). Then, in a subsequent hydrothermal treatment, the remaining Ag+ ions were reduced by PVP into polyhedral nanoparticles, or larger spherical nanoparticles formed from the small spherical seed silver nanoparticles in the first step. The morphology and size of the resultant particles depend on the hydrothermal temperature, PVP/Ag molar ratio and concentration of Ag+ ions. By using UV-visible spectroscopy (UV-vis), transmission electron microscopy (TEM) and powder X-ray diffraction (XRD), the possible growth mechanism of the silver nanoparticles was discussed.Juan Zou Yao Xu Bo Hou Dong Wu Yuhan Sun 2007China Particuology2007,5,3:6
19Ginsenoside Rg1 ameliorates bloodebrain barrier disruption and traumatic brain injury via attenuating macrophages derived exosomes miR-21 release显示文摘During the traumatic brain injury(TBI),improved expression of circulatory miR-21 serves as a diagnostic feature.Low levels of exosome-miR-21 in the brain can effectively improve neuroinflammation and bloodebrain barrier(BBB)permeability,reduce nerve apoptosis,restore neural function and ameliorate TBI.We evaluated the role of macrophage derived exosomes-miR-21(M-Exos-miR-21)in disrupting BBB,deteriorating TBI,and Rg1 interventions.IL-1β-induced macrophages(ⅡA)-Exos-miR-21 can activate NF-kB signaling pathway and induce the expressions of MMP-1,-3 and-9 and downregulate the levels of tight junction proteins(TJPs)deteriorating the BBB.Rg1 reduced miR-21-5 p content in ⅡA-Exos(RⅡA-Exos).The interaction of NMIIAe HSP90 controlled the release of Exos-miR-21,this interaction was restricted by Rg1.Rg1 could inhibit the Exos-miR-21 release in peripheral blood flow to brain,enhancing TIMP3 protein expression,MMPs proteolysis,and restricting TJPs degradation thus protected the BBB integrity.Conclusively,Rg1 can improve the cerebrovascular endothelial injury and hold the therapeutic potential against TBI disease.Kefeng Zhai Hong Duan Wei Wang Siyu Zhao Ghulam Jilany Khan Mengting Wang Yuhan Zhang Kiran Thakur Xuemei Fang Chao Wu Jianbo Xiao Zhaojun Wei 2021Acta Pharmaceutica Sinica B2021,11,11:6
20Super-resolution compressive spectral imaging via two-tone adaptive coding显示文摘Coded apertures with random patterns are extensively used in compressive spectral imagers to sample the incident scene in the image plane.Random samplings,however,are inadequate to capture the structural characteristics of the underlying signal due to the sparsity and structure nature of sensing matrices in spectral imagers.This paper proposes a new approach for super-resolution compressive spectral imaging via adaptive coding.In this method,coded apertures are optimally designed based on a two-tone adaptive compressive sensing(CS)framework to improve the reconstruction resolution and accuracy of the hyperspectral imager.A liquid crystal tunable filter(LCTF)is used to scan the incident scene in the spectral domain to successively select different spectral channels.The output of the LCTF is modulated by the adaptive coded aperture patterns and then projected onto a lowresolution detector array.The coded aperture patterns are implemented by a digital micromirror device(DMD)with higher resolution than that of the detector.Due to the strong correlation across the spectra,the recovered images from previous spectral channels can be used as a priori information to design the adaptive coded apertures for sensing subsequent spectral channels.In particular,the coded apertures are constructed from the a priori spectral images via a two-tone hard thresholding operation that respectively extracts the structural characteristics of bright and dark regions in the underlying scenes.Super-resolution image reconstruction within a spectral channel can be recovered from a few snapshots of low-resolution measurements.Since no additional side information of the spectral scene is needed,the proposed method does not increase the system complexity.Based on the mutual-coherence criterion,the proposed adaptive CS framework is proved theoretically to promote the sensing efficiency of the spectral images.Simulations and experiments are provided to demonstrate and assess the proposed adaptive coding method.Finally,the underlying concepts are extended to a multi-channel method to compress the hyperspectral data cube in the spatial and spectral domains simultaneously.CHANG XU TINGFA XU GE YAN XU MA YUHAN ZHANG XI WANG FENG ZHAO GONZALO R.ARCE 2020Photonics Research2020,8,3:6
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