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QUANTILE ESTIMATION WITH AUXILIARY INFORMATION UNDER POSITIVELY ASSOCIATED SAMPLES 被引量:1
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作者 李英华 秦永松 +1 位作者 雷庆祝 李丽凤 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期453-468,共16页
The empirical likelihood is used to propose a new class of quantile estimators in the presence of some auxiliary information under positively associated samples. It is shown that the proposed quantile estimators are a... The empirical likelihood is used to propose a new class of quantile estimators in the presence of some auxiliary information under positively associated samples. It is shown that the proposed quantile estimators are asymptotically normally distributed with smaller asymptotic variances than those of the usual quantile estimators. 展开更多
关键词 QUANTILE positively associated sample empirical likelihood
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Treatment of Textile Dye Effluent Using a Self-made Positively Charged Nanofiltration Membrane 被引量:1
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作者 黄瑞华 YANG Bingchao +2 位作者 ZHENG Dongsheng CHEN Guohua GAO Congjie 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第2期199-202,共4页
A selfmade positively charged nanofiltration (NF) membrane was used to treat textile dye effluent to generate water for reuse, and the factors affecting nanofiltration process such as operating pressure, feed flow a... A selfmade positively charged nanofiltration (NF) membrane was used to treat textile dye effluent to generate water for reuse, and the factors affecting nanofiltration process such as operating pressure, feed flow and membrane cleaning were investigated. With an applied pressure of 1.0 MPa and a feed flow of 40 L/h, this NF membrane has a removal of 93.3% for CODor and a reduction of approximately 51.0% in TDS, salinity and conductivity achieving the chroma removal of 100%. The permeate obtained through this membrane is suitable for recycling. Moreover, the membrane could be reused after being cleaned with 1% NaOH solution. 展开更多
关键词 positively charged nanofiltration membrane textile dye effluent RECYCLING
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Response of the low-pressure hot-filament discharge plasma to a positively biased auxiliary disk electrode
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作者 Mangilal CHOUDHARY Poyyeri Kunnath SREEJITH 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第1期53-60,共8页
In a steady-state plasma,the loss rate of plasma particles to the chamber wall and surfaces in contact with plasma is balanced by the ionization rate of background neutrals in the hot-filament discharges.The balance b... In a steady-state plasma,the loss rate of plasma particles to the chamber wall and surfaces in contact with plasma is balanced by the ionization rate of background neutrals in the hot-filament discharges.The balance between the loss rate and ionization rate of plasma particles(electrons and ions)maintains quasi-neutrality of the bulk plasma.In the presence of an external perturbation,it tries to retain its quasi-neutrality condition.In this work,we studied how the properties of bulk plasma are affected by an external DC potential perturbation.An auxiliary biased metal disk electrode was used to introduce a potential perturbation to the plasma medium.A single Langmuir probe and an emissive probe,placed in the line of the discharge axis,were used for the characterization of the bulk plasma.It is observed that only positive bias to the auxiliary metal disk increases the plasma potential,electron temperature,and plasma density but these plasma parameters remain unaltered when the disk is biased with a negative potential with respect to plasma potential.The observed plasma parameters for two different-sized,positively as well as negatively biased,metal disks are compared and found inconsistent with the existing theoretical model at large positive bias voltages.The role of the primary energetic electrons population in determining the plasma parameters is discussed.The experimentally observed results are qualitatively explained on the basis of electrostatic confinement arising due to the loss of electrons to a biased metal disk electrode. 展开更多
关键词 hot-filament discharge plasma response plasma parameters positively biased electrode
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Stabilizing model predictive control scheme for piecewise affine systems with maximal positively invariant terminal set
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作者 Fu Chen Guangzhou Zhao Xiaoming Yu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1090-1094,共5页
An efficient algorithm is proposed for computing the solution to the constrained finite time optimal control (CFTOC) problem for discrete-time piecewise affine (PWA) systems with a quadratic performance index. The... An efficient algorithm is proposed for computing the solution to the constrained finite time optimal control (CFTOC) problem for discrete-time piecewise affine (PWA) systems with a quadratic performance index. The maximal positively invariant terminal set, which is feasible and invariant with respect to a feedback control law, is computed as terminal target set and an associated Lyapunov function is chosen as terminal cost. The combination of these two components guarantees constraint satisfaction and closed-loop stability for all time. The proposed algorithm combines a dynamic programming strategy with a multi-parametric quadratic programming solver and basic polyhedral manipulation. A numerical example shows that a larger stabilizable set of states can be obtained by the proposed algorithm than precious work. 展开更多
关键词 constrained optimal predictive control multi-parametric quadratic programming dynamic programming receding horizon control positively invariant set.
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A Bound State of a Positively Charged Exciton in Quantum Dots
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作者 解文方 《Chinese Physics Letters》 SCIE CAS CSCD 2001年第2期266-268,共3页
Using the method of few-body physics,we obtain the relation between the correlation energies of the low-lying states of the positively charged exciton X+and the radius of quantum dots.We also calculate the binding ene... Using the method of few-body physics,we obtain the relation between the correlation energies of the low-lying states of the positively charged exciton X+and the radius of quantum dots.We also calculate the binding energies of the ground state of a positively charged exciton as a function of the electron-to-hole mass ratio for a few values of the strength of the confinement.We find that there exists a critical mass ratioσ^(c),such that ifσ>σ^(c)(σ<σ^(c))the X^(+)configuration is stable(unstable),andσc increases as the strength of the confinement increases. 展开更多
关键词 positively RADIUS QUANTUM
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Genome-Wide Scan for Positively Selected Genes in Sessile Molluscs Highlights the Genetic Basis for Their Adaptation to Attached Lifestyle
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作者 YU Hong LI Qi 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第4期920-924,共5页
Molluscs are one of the most diverse groups of animals and exhibit a rich and diverse variety of form and lifestyle. Most molluscs live with a free-moving lifestyle, while some molluscs are sessile. The adaptation to ... Molluscs are one of the most diverse groups of animals and exhibit a rich and diverse variety of form and lifestyle. Most molluscs live with a free-moving lifestyle, while some molluscs are sessile. The adaptation to the two distinct lifestyles required complex changes, from molecules to organs, and physiology to morphology. In this study, we conducted a genome-wide scan for positive selection by comparing the available genomes of two sessile molluscs with four free-moving molluscs. A total of 40 genes were identified undergoing positive selection in the sessile molluscs by the branch-site model. Functional characterization showed that they were mainly enriched in two pathways, Oxidative phosphorylation(OXPHOS) and TGF-beta signaling pathway. The unexpected positive selection on OXPHOS genes in sessile molluscs suggests that the adaptation of OXPHOS involves many factors beyond enhancing ATP production. A modified OXPHOS regulatory system may allow sessile molluscs to better cope with biotic and abiotic stresses. Moreover, positively selected genes in TGF-beta signaling pathway probably have played a key role in the patterning of body plans and growth in metazoans. We speculate that these genes are associated with the body structure and organic adaptation to a sedentary lifestyle in sessile bivalve molluscs. 展开更多
关键词 molluscs ADAPTATION evolution positive selection sessile LIFESTYLE
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FUNDAMENTAL GROUPS OF CLOSED POSITIVELY CURVED MANIFOLDS WITH ALMOST DISCRETE ABELIAN GROUP ACTIONS
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作者 王雨生 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期203-207,共5页
Let M be a closed n-manifold of positive sectional curvature. Assume that M admits an effective isometrical T1× Zpk-action with p prime. The main result of the article n+1 for n 〉 5, then there exists a positiv... Let M be a closed n-manifold of positive sectional curvature. Assume that M admits an effective isometrical T1× Zpk-action with p prime. The main result of the article n+1 for n 〉 5, then there exists a positive constant p(n), is that ifk=lforn=3or k〉 n+1/4 for n≥5,then there exists a positive constant p(n),depending only on n, such that π1 (M) is cyclic if p ≥ p(n). 展开更多
关键词 fundamental groups positive sectional curvature group actions
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Effect of Electron and/or Ion Nonthermality on Dust Acoustic Wave Propagation in a Complex Plasma in Presence of Positively Charged Dust Grains Generated by Secondary Electron Emission Process
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作者 Susmita Sarkar Subrata Bhakta 《Journal of Modern Physics》 2016年第1期74-86,共13页
In this paper we have developed a model to study the role of both electron and ion nonthermalities on dust acoustic wave propagation in a complex plasma in presence of positively charged dust grains. Secondary electro... In this paper we have developed a model to study the role of both electron and ion nonthermalities on dust acoustic wave propagation in a complex plasma in presence of positively charged dust grains. Secondary electron emission from dust grains has been considered as the source of positive dust charging. As secondary emission current depends on the flux of primary electrons, nonthermality of primary electrons changes the expression of secondary emission current from that of earlier work where primary electrons were thermal. Expression of nonthermal electron current flowing to the positively charged dust grains and consequently the expression of secondary electron current flowing out of the dust grains have been first time calculated in this paper, whereas the expression for nonthermal ion current flowing to the positively charged dust grains is present in existing literature. Dispersion relation of dust acoustic wave has been derived. From this dispersion relation real frequency and growth rate of the wave have been calculated. Results have been plotted for different strength of nonthermalities of electrons and ions. 展开更多
关键词 Complex Plasma Nonthermality Positive Dust Secondary Electron Emission
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持续气道正压通气治疗重症阻塞性睡眠呼吸暂停低通气综合征伴黏多糖病患儿1例
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作者 马薇 范杰 +1 位作者 苏晓艳 谢宇平 《中国耳鼻咽喉头颈外科》 CSCD 2024年第7期474-474,476,共2页
1临床资料患儿,男,6岁,因“睡眠打鼾2年余,加重伴憋气2 d”于2022-09-09就诊于甘肃省人民医院。患儿自幼体格生长和智力发育较同龄儿落后,面容特殊;入院前2年无明显诱因出现鼻塞、睡眠时张口呼吸,打鼾憋气,感冒时鼻塞、打鼾症状尤为明显... 1临床资料患儿,男,6岁,因“睡眠打鼾2年余,加重伴憋气2 d”于2022-09-09就诊于甘肃省人民医院。患儿自幼体格生长和智力发育较同龄儿落后,面容特殊;入院前2年无明显诱因出现鼻塞、睡眠时张口呼吸,打鼾憋气,感冒时鼻塞、打鼾症状尤为明显,有时伴有耳痛。入院前1周患儿感冒后鼻塞加重,近两日夜间睡眠打鼾加重,伴明显憋气,夜间口唇青紫。患儿父母非近亲婚配,其家族中未发现类似情况。查体:身高63 cm,体重22 kg,特殊面容. 展开更多
关键词 粘多糖病 粘多糖累积病(Mucopolysaccharidoses) 睡眠呼吸暂停 阻塞性(Sleep Apnea Obstructive) 持续正压气道压力 连续气道正压通气(Continuous Positive Airway Pressure)
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在特定领域进一步赋予人类权力并重新思考AGI测试
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作者 Yue-Guang Lyu Fei Wu 《Engineering》 SCIE EI CAS CSCD 2024年第3期1-2,共2页
Artificial intelligence(AI)has emerged as a transformative force with the potential to positively impact every facet of society.One of its most profound applications lies in its ability to empower individuals within c... Artificial intelligence(AI)has emerged as a transformative force with the potential to positively impact every facet of society.One of its most profound applications lies in its ability to empower individuals within communities by leveraging their strengths,promoting independence,and aiding them in achieving their goals.Human uses for AI have grown across every aspect of society;from language generation to molecular synthesis,AI has begun to permeate every aspect of our lives. 展开更多
关键词 INDEPENDENCE SYNTHESIS positively
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Genetic mechanism of body size variation in groupers:Insights from phylotranscriptomics
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作者 Wei-Wei Zhang Zhuo-Ying Weng +5 位作者 Xi Wang Yang Yang Duo Li Le Wang Xiao-Chun Liu Zi-Ning Meng 《Zoological Research》 SCIE CSCD 2024年第2期314-328,共15页
Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within ... Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within the fish genus Epinephelus with evident divergence in body size,providing an excellent opportunity to investigate the genetic basis of body size variation in vertebrates.Herein,we performed phylotranscriptomic analysis and reconstructed the phylogeny of 13 epinephelids originating from the South China Sea.Two genetic clades with an estimated divergence time of approximately 15.4 million years ago were correlated with large and small body size,respectively.A total of 180 rapidly evolving genes and two positively selected genes were identified between the two groups.Functional enrichment analyses of these candidate genes revealed distinct enrichment categories between the two groups.These pathways and genes may play important roles in body size variation in groupers through complex regulatory networks.Based on our results,we speculate that the ancestors of the two divergent groups of groupers may have adapted to different environments through habitat selection,leading to genetic variations in metabolic patterns,organ development,and lifespan,resulting in body size divergence between the two locally adapted populations.These findings provide important insights into the genetic mechanisms underlying body size variation in groupers and species differentiation. 展开更多
关键词 Phylotranscriptomics GROUPER Body size Rapidly evolving genes(REGs) positively selected genes(PSGs)
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Arabidopsis small ubiquitin-related modifier protease ASP1 positively regulates abscisic acid signaling during early seedling development~~ 被引量:5
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作者 Qiongli wang Gao-Ping Qu +3 位作者 Xiangxiong Kong Yan Yan Jigang Li Jing Bo Jin 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2018年第10期924-937,共14页
The small ubiquitin-related modifier (SUMO) modification plays an important role in the regulation of abscisic acid (ABA) signaling, but the function of the SUMO protease, in ABA signaling, remains largely unknown... The small ubiquitin-related modifier (SUMO) modification plays an important role in the regulation of abscisic acid (ABA) signaling, but the function of the SUMO protease, in ABA signaling, remains largely unknown. Here, we show that the SUMO protease, ASPI positively regulates ABA signaling. Mutations in ASPI resulted in an ABA-insensitive phenotype, during early seedling develop- ment. Wild-type ASP1 successfully rescued, whereas an ASPI mutant (C577S), defective in SUMO protease activity, failed to rescue, the ABA-insensitive phenotype of asp1-1. Expression of ABI5 and MYB3o target genes was attenuated in asp^-I and our genetic analyses revealed that ASP1 may function upstream of ABI5 and MYB3o. 展开更多
关键词 ASP ABA Arabidopsis small ubiquitin-related modifier protease ASP1 positively regulates abscisic acid signaling during early seedling development ABI Figure
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THESEUS1 positively modulates plant defense responses against Botrytis cinerea through GUANINE EXCHANGE FACTOR4 signaling 被引量:3
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作者 shaofeng qu xi zhang +2 位作者 yutong song jinxing lin xiaoyi shan 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2017年第11期797-804,共8页
The plant cell wall is an important interface for sensing pathogen attack and activating signaling pathways that promote plant immune responses.THESEUS1(THE1) acts as a sensor of cell wall integrity that controls cell... The plant cell wall is an important interface for sensing pathogen attack and activating signaling pathways that promote plant immune responses.THESEUS1(THE1) acts as a sensor of cell wall integrity that controls cell elongation during plant growth.However, no specific role for THE1 in plant defense responses has been reported. Here, we found that THE1 interacts with GUANINE EXCHANGE FACTOR4(GEF4)and that both proteins play regulatory roles in plant resistance to the necrotrophic fungus Botrytis cinerea.Genetic analysis showed that THE1 and GEF4 function in the same genetic pathway to mediate plant defense responses. In addition, using transcriptome analysis, we identified various genes(such as defense-related,secondary metabolite-related, and transcription factor genes) that are likely downstream targets in the THE1-GEF4 signaling pathway. Our results suggest that THE1 functions as an upstream regulator of GEF4 signaling to positively regulate defense responses against B. cinerea in Arabidopsis. 展开更多
关键词 THESEUS1 positively modulates plant responses against Botrytis cinerea GUANINE EXCHANGE FACTOR4 signaling
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Driving pressure in mechanical ventilation:A review 被引量:1
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作者 Syeda Farheen Zaidi Asim Shaikh +2 位作者 Daniyal Aziz Khan Salim Surani Iqbal Ratnani 《World Journal of Critical Care Medicine》 2024年第1期15-27,共13页
Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(MV).Varying levels ofΔP have been employed during MV depending on the type of underlying pathology and severity of injury.However,ΔP lev... Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(MV).Varying levels ofΔP have been employed during MV depending on the type of underlying pathology and severity of injury.However,ΔP levels have also been shown to closely impact hard endpoints such as mortality.Considering this,conducting an in-depth review ofΔP as a unique,outcome-impacting therapeutic modality is extremely important.There is a need to understand the subtleties involved in making sureΔP levels are optimized to enhance outcomes and minimize harm.We performed this narrative review to further explore the various uses ofΔP,the different parameters that can affect its use,and how outcomes vary in different patient populations at different pressure levels.To better utilizeΔP in MV-requiring patients,additional large-scale clinical studies are needed. 展开更多
关键词 Driving pressure Acute respiratory distress syndrome MORTALITY Positive end-expiratory pressure Ventilator induced lung injury Mechanical ventilation
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Positively charged microporous ceramic membrane for the removal of Titan Yellow through electrostatic adsorption 被引量:5
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作者 Xiuting Cheng Na Li +3 位作者 Mengfu Zhu Lili Zhang Yu Deng Cheng Deng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第6期204-212,共9页
To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane.The internal surface of the highly por... To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane.The internal surface of the highly porous ceramic membrane was coated with uniformly distributed electropositive nano-Y2O3 coating. The dye removal performance was evaluated through pressurized filtration tests using Titan Yellow aqueous solution. It showed that positively charged microporous ceramic membrane exhibited a flow rate of 421 L/(m^2·hr) under the trans-membrane pressure of 0.03 bar. Moreover it could effectively remove Titan Yellow with feed concentration of 10 mg/L between pH 3 to 8. The removal rate increased with the enhancement of the surface charge properties with a maximum rejection of 99.6%. This study provides a new and feasible method of removing organic dyes in wastewater. It is convinced that there will be a broad market for the application of charged ceramic membrane in the field of dye removal or recovery from industry wastewater. 展开更多
关键词 positively charged ceramic membrane Electrostatic adsorption Organic dyes Wastewater treatment
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Direct electrochemistry and enzymatic activity of hemoglobin in positively charged colloid Au nanoparticles and hemoglobin layer-by-layer self-assembly films 被引量:1
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作者 YUAN Ruo CAO ShuRui CHAI YaQin GAO FengXian ZHAO Qing TANG MingYu TONG ZhongQiang XIE Yi 《Science China Chemistry》 SCIE EI CAS 2007年第5期620-628,共9页
Alternate adsorption of positively charged colloid-Au nanoparticles (nano-Au⊕) and negatively charged hemoglobin (Hb) on L-cysteine (L-cys) modified gold electrode resulted in the assembly of {Hb/nano-Au⊕}n layer-by... Alternate adsorption of positively charged colloid-Au nanoparticles (nano-Au⊕) and negatively charged hemoglobin (Hb) on L-cysteine (L-cys) modified gold electrode resulted in the assembly of {Hb/nano-Au⊕}n layer-by-layer films/L-cys modified gold electrode. The nano-Au⊕ was characterized by transmission electron micrograph (TEM) and microelectrophoresis. The modified electrode interface morphology was characterized by electrochemical impedance spectroscopy (EIS), atomic force mi- croscopy (AFM), cyclic voltammograms (CV) and chronoamperometry. Direct electron transfer between hemoglobin and gold electrodes was studied, and the apparent Michaelis-Menten constant ( km app) of the modified electrode was evaluated to be 0.10 mmol·L?1. Moreover, the higher activity of proteins in the nano-Au⊕ films could be retained compared with the electropolymerization membrane, since the pro- teins in nano-Au⊕ films retained their near-native structure. Direct electron transfer between hemoglo- bin and electrode and electrochemically catalyzed reduction of hydrogen peroxide on a modified elec- trode was studied, and the linear range was from 2.1×10-8 to 1.2 ×10?3 mol·L-1 (r = 0.994) with a detection limit of 1.1×10-8 mol·L-1 H2O2. 展开更多
关键词 positively CHARGED colloid-Au nanoparticles (nano-Au(Ξ) hemoglobin catalyze hydrogen PEROXIDE
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A novel positively thermo-sensitive hydrogel based on ethylenediaminetetraacetic dianhydride and piperazine:Design,synthesis and characterization 被引量:2
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作者 Jiao Xia Sun Yuan Liang Wang Shu Hua Dou 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第1期97-100,共4页
A new positively thermo-sensitive hydrogel was designed and synthesized by a condensation polymerization reaction of ethylenediaminetetraacetic dianhydride(EDTAD) and piperazine(PA) to give poly(ethylenediaminete... A new positively thermo-sensitive hydrogel was designed and synthesized by a condensation polymerization reaction of ethylenediaminetetraacetic dianhydride(EDTAD) and piperazine(PA) to give poly(ethylenediaminetetraacetic dianhydride-copiperazine) (PEP).The obtained polymers' structure was characterized by FTIR and ^(13)C NMR.The backbone of the polymer linked by amide bond and abundant of carboxyl groups as pendant group could form strong intermolecular and intramolecular hydrogen bond at lower temperature and dissociate at higher temperature,resulting in the polymer with thermo-sensitivity.The aqueous solution of PEP at lower temperature(〈20℃) showed micro-gel formation and transformed to transparent solution at higher temperature(〉40℃).Transition temperature shifted to higher value with the increasing of concentration.The hydrogel exhibited reversible phase transition and the transmittance change was not weakened by multiple temperature changes. 展开更多
关键词 positively thermo-sensitive hydrogel Degradation Ethylenediaminetetraacetic dianhydride Piperazine
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Collaborative positioning for swarms:A brief survey of vision,LiDAR and wireless sensors based methods
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作者 Zeyu Li Changhui Jiang +3 位作者 Xiaobo Gu Ying Xu Feng zhou Jianhui Cui 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期475-493,共19页
As positioning sensors,edge computation power,and communication technologies continue to develop,a moving agent can now sense its surroundings and communicate with other agents.By receiving spatial information from bo... As positioning sensors,edge computation power,and communication technologies continue to develop,a moving agent can now sense its surroundings and communicate with other agents.By receiving spatial information from both its environment and other agents,an agent can use various methods and sensor types to localize itself.With its high flexibility and robustness,collaborative positioning has become a widely used method in both military and civilian applications.This paper introduces the basic fundamental concepts and applications of collaborative positioning,and reviews recent progress in the field based on camera,LiDAR(Light Detection and Ranging),wireless sensor,and their integration.The paper compares the current methods with respect to their sensor type,summarizes their main paradigms,and analyzes their evaluation experiments.Finally,the paper discusses the main challenges and open issues that require further research. 展开更多
关键词 Collaborative positioning VISION LIDAR Wireless sensors Sensor fusion
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Analysis of environmental selection pressure of superoxide dismutase in deep-sea sea cucumber
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作者 Yanan LI Zongfu CHEN +3 位作者 Haibin ZHANG Ruoyu LIU Shuichun CHEN Li LIN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期893-904,共12页
Manganese superoxide dismutase(MnSOD)is an antioxidant that exists in mitochondria and can effectively remove superoxide anions in mitochondria.In a dark,high-pressure,and low-temperature deep-sea environment,MnSOD is... Manganese superoxide dismutase(MnSOD)is an antioxidant that exists in mitochondria and can effectively remove superoxide anions in mitochondria.In a dark,high-pressure,and low-temperature deep-sea environment,MnSOD is essential for the survival of sea cucumbers.Six MnSODs were identified from the transcriptomes of deep and shallow-sea sea cucumbers.To explore their environmental adaptation mechanism,we conducted environmental selection pressure analysis through the branching site model of PAML software.We obtained night positive selection sites,and two of them were significant(97F→H,134K→V):97F→H located in a highly conservative characteristic sequence,and its polarity c hange might have a great impact on the function of MnSOD;134K→V had a change in piezophilic a bility,which might help MnSOD adapt to the environment of high hydrostatic pressure in the deepsea.To further study the effect of these two positive selection sites on MnSOD,we predicted the point mutations of F97H and K134V on shallow-sea sea cucumber by using MAESTROweb and PyMOL.Results show that 97F→H,134K→V might improve MnSOD’s efficiency of scavenging superoxide a nion and its ability to resist high hydrostatic pressure by moderately reducing its stability.The above results indicated that MnSODs of deep-sea sea cucumber adapted to deep-sea environments through their amino acid changes in polarity,piezophilic behavior,and local stability.This study revealed the correlation between MnSOD and extreme environment,and will help improve our understanding of the organism’s adaptation mechanisms in deep sea. 展开更多
关键词 HOLOTHUROIDEA environmental adaptation positive selection point mutation
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Tuning the diffusion constant to optimize the readout of positional information of spatial concentration patterns
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作者 江嘉杰 罗春雄 刘峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期579-586,共8页
Positional information encoded in spatial concentration patterns is crucial for the development of multicellular organisms.However,it is still unclear how such information is affected by the physically dissipative dif... Positional information encoded in spatial concentration patterns is crucial for the development of multicellular organisms.However,it is still unclear how such information is affected by the physically dissipative diffusion process.Here we study one-dimensional patterning systems with analytical derivation and numerical simulations.We find that the diffusion constant of the patterning molecules exhibits a nonmonotonic effect on the readout of the positional information from the concentration patterns.Specifically,there exists an optimal diffusion constant that maximizes the positional information.Moreover,we find that the energy dissipation due to the physical diffusion imposes a fundamental upper limit on the positional information. 展开更多
关键词 pattern formation positional information mutual information DIFFUSION
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