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Spherical Confinement Generates Entropic Force to Accelerate Polymer Chain Detachment

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Chinese Journal of Polymer Science 2024年第3期42卷 407-416,I0010页

作者： Yu-Shan Zheng jian-ping Zhou yan Xu Kai Li Mechanical Engineering Xinjiang UniversityUrumqi 830002China

To understand the dynamic process of polymer detachment, it is necessary to determine the mean detachment time of a single breakable link, which is modeled as a spring. Normally, this time can be viewed as the escape of a Brownian particle from the potential well of the spring. However, as the free dangling length of the polymer chain increases, the conformational entropy of the chain is affected by geometric confinement. It means that the wall exerts a repulsive force on the chain, resulting in accelerated link detachment from a macroscopic perspective. In this work, we investigate the effect of entropy on the detachment rate in the case where the substrate is spherical. We demonstrate that spherical confinement accelerates chain detachment both inside and outside the sphere. An analytical expression for the mean detachment time of breakable links is given, which includes an additional pre-factor that is related to the partition function. Additionally, we analyze the expressions for entropic forces inside the sphere, outside the sphere, and on a flat wall, comparing their magnitudes to explain the difference in mean detachment time.

关键词： Polymer detachment Breakable link Entropic force Mean first passage time

Laguerre-Gauss collocation method for initial value problems of second order ODEs

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Applied Mathematics and Mechanics(English Edition) 2011年第12期32卷 1541-1564页

作者：严建平郭本瑜 Department of Mathematics Shanghai Normal University Department of Applied Mathematics Guangdong University of Finance Scientific Computing Key Laboratory of Shanghai Universities Division of Computational Science of E-institute of Shanghai Universities

This paper proposes a new collocation method for initial value problems of second order ODEs based on the Laguerre-Gauss interpolation. It provides the global numerical solutions and possesses the spectral accuracy. N... 详细信息

关键词： Laguerre-Gauss collocation method initial value problem second orderODEs

MUC1-positive circulating tumor cells and MUC1 protein predict chemotherapeutic efficacy in the treatment of metastatic breast cancer

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Chinese Journal of Cancer 2011年第1期30卷 54-61页

作者： jian-ping Cheng Ying yan Xiang-Yi Wang Yuan-Li Lu yan-Hua Yuan Jun Jia Jun Ren Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Peking University School of Oncology Department of Medical Oncology Beijing Cancer Hospital & Institute Beijing 100142 P. R. China.

Chemotherapy plays an important role in the treatment of metastatic breast cancer. It is important to monitor chemotherapeutic efficacy, to find a simple and efficient tool to guide treatment, and to predict the efficacy of treatment in a timely and accurate manner. This study aimed to detect mucin-1 (MUC1) - positive circulating tumor cells and MUC1 protein in the peripheral blood of patients with metastatic breast cancer and to investigate their relationship to chemotherapeutic efficacy. MUC1 mRNA was detected in the peripheral blood of 34 patients with newly diagnosed metastatic breast cancer by reverse transcription- polymerase chain reaction. The positive rates of MUC1 mRNA were 88.2% before chemotherapy and 70.6% after chemotherapy, without a significant difference (P = 0.564); MUC1 mRNA expression before chemotherapy had no correlation with treatment effectiveness (P = 0.281). The response rate of MUC1 mRNA -negative patients after first-cycle chemotherapy was significantly higher (P = 0.009) and the progression-free survival (PFS) was clearly longer than those of MUC1 mRNA-positive patients (P = 0.095). MUC1 protein in peripheral blood plasma was detected by an ELISA competitive inhibition assay. The patients with decreased MUC1 protein after chemotherapy had a significantly longer PFS than those with elevated MUC1 protein (P = 0.044). These results indicate that the outcomes of MUC1 mRNA - negative patients after chemotherapy are better than those of MUC1 mRNA-positive patients. In addition, patients with decreased expression of MUC1 protein have a better PFS.

关键词： MUC1 治疗效果肿瘤细胞阳性率乳腺癌转移性粘蛋白化疗

Phase regulated suppression and enhancement switches of four-wave mixing and fluorescence

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Frontiers of physics 2014年第2期9卷 153-156页

作者： Zhi-Guo Wang Peng Ying Pei-Ying Li Hua-yan Lan He-Qing Huang Hao Tian jian-ping Song yan-Peng Zhang Key Laboratory for Physical Electronics and Devices of the Ministry of Education Shaanxi Key Lab of Information Photonic Technique Xi'an Jiaotong University Xi'an 710049 China

We experimentally study the phase regulated switch between elcctromagnctically induced trans- parency and electromagmetically induced absorption in probe transmission signal and the conver- sion between enhancement and suppression in four-wave mixing and fluorescence signals for the first time. By changing the relative phase, electromagnetically induced transparency can be eonverted into electromagnetically induced absorption. In this process, the conversion from suppression to enhancement is also obtained in four-wave mixing and fluorescence signals. This research can be applied in non-linear optical device like optical switch and optical wavelength convertor.

关键词： four-wave mixing fluorescence phase regulation enhancement and suppression

Quantitative characterizations of anisotropic dynamic properties in organic-rich shale with different kerogen content

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Petroleum Science 2024年第2期21卷 855-865页

作者： jian-Yong Xie yan-ping Fang Xing-Hua Wu jian'er Zhao Jun-Cheng Dai Jun-Xing Cao Ji-Xin Deng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina Key Lab of Earth Exploration&Information Techniques of Ministry of Education Geophysical InstituteChengdu University of TechnologyChengdu610059SichuanChina PetroChina Southwest Oil&Gasfield Company Chengdu610017SichuanChina

Understanding the quantitative responses of anisotropic dynamic properties in organic-rich shale with different kerogen content(KC)is of great significance in hydrocarbon exploration and *** controlled experiments with a single variable is challenging for natural shales due to their high variations in components,diagenesis conditions,or pore *** employed the hot-pressing technique to construct 11 well-controlled artificial shale with varying *** artificial shale samples were successive machined into prismatic shape for ultrasonic measurements along different *** revealed bedding perpendicular P-wave velocities are more sensitive to the increasing KC than bedding paralleling velocities due to the preferential alignments of *** elastic stiffnesses except C_(13)are generally decreasing with the increasing KC,the variation of C_(1) and C_(33)on kerogen content are more sensitive than those of C_(44)and C_(66).Apparent dynamic mechanical parameters(v and E)were found to have linear correlation with the true ones from complete anisotropic equations independent of KC,which hold value towards the interpretation of well logs consistently across formations,Anisotropic mechanical parameters(ΔE and brittlenessΔB)tend to decrease with the reducing KC,withΔB showing great sensitivity to KC *** the range of low KC(10%)shale,compilation of data from natural organic rich-shales globally verified the similar systematic relationships that can be empirically used to predict the fraction of KC in shales.

关键词： Elastic properties Organic shale Anisotropy Kerogen content Physical modeling

Design and Application of an S-band Fast Radio Bursts Search Pipeline for the Nanshan 26 m Radio Telescope

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Research in Astronomy and Astrophysics 2024年第7期24卷 111-117页

作者： yan-Ling Liu Mao-Zheng Chen jian Li jian-ping Yuan Rai Yuen Zhi-Yong Liu Hao yan Wen-Long Du Nan-Nan Zhai Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Fast radio bursts(FRBs)are among the most studied radio transients in astrophysics,but their origin and radiation mechanism are still *** is a challenge to search for FRB events in a huge amount of observational data with high speed and high *** the rapid advancement of the FRB research process,FRB searching has changed from archive data mining to either long-term monitoring of the repeating FRBs or all-sky surveys with specialized ***,establishing a highly efficient and high quality FRB search pipeline is the primary task in FRB *** learning techniques provide new ideas for FRB search *** have detected radio bursts from FRB 20201124A in the L-band observational data of the Nanshan 26 m radio telescope(NSRT-26m)using the constructed deep learning based search pipeline named dispersed dynamic spectra search(DDSS).Afterwards,we further retrained the deep learning model and applied the DDSS framework to S-band *** this paper,we present the FRB observation system and search pipeline using the S-band *** carried out search experiments,and successfully detected the radio bursts from the magnetar SGR J1935+2145and FRB *** experimental results show that the search pipeline can complete the search efficiently and output the search results with high accuracy.

关键词： radio continuum general-methods data analysis-methods observational

Silencing transformer and transformer-2 in Zeugodacus cucurbitae causes defective sex determination with inviability of most pseudomales

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Journal of Integrative Agriculture 2024年第3期23卷 938-947页

作者： Qin Ma Zizhen Fan ping Wang Siya Ma jian Wen Fengqin Cao Xianwu Lin Rihui yan Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests of Ministry of Education School of Plant ProtectionHainan UniversityHaikou 570228China School of Life Sciences HainanUniversityHaikou 570228China Hainan Yazhou Bay Seed Lab Sanya 572000China

transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked Maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control.

关键词： Zeugodacus cucurbitae transformer transformer-2 sex determination RNA interference biological control

Microstructures and Properties of Honeycomb Sulfur/carbon Black/MoS_(2) Composites

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1073-1078页

作者： CUI Chunjuan LIU Yue ZHAO yanan LIU yanyun WANG yan WEI jian HU ping School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi'an 710055China Shaanxi Metallurgical Engineering Technology Research Center Xi’an 710055China School of Materials Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Microstructure and property of sulfur/carbon black composites prepared by ball milling were ***/carbon black composites were obtained by melting the mixture of sulfur and carbon black in 155℃and dispersing evenly in carbon black after hydrothermal ***,its conductive properties were ***,microstructure and property of honeycomb sulfur/carbon black/MoS_(2) prepared by hydrothermal method as a cathode material for lithium-sulfur batteries were *** initial discharge specific capacity of the material at 0.2 A/g current density is 838.495 mA·h/g,and the 55.14%after 100 weeks of *** is indicated that MoS_(2) can not only combine with polysulfides through electrostatic action or the action of chemical bonds,but also honeycomb porous ***_(2) can fix polysulfides groups and prevent their ***,the cycling performance of the battery is effectively improved.

关键词： lithium-sulfur battery honeycomb MoS_(2) charge/discharge performance

Channel assignment and power allocation for throughput improvement with PPO in B5G heterogeneous edge networks

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Digital Communications and Networks 2024年第1期10卷 109-116页

作者： Xiaoming He Yingchi Mao Yinqiu Liu ping ping yan Hong Han Hu The College of Computer and Information Hohai UniversityNanjingChina The Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjing China The School of Computer Science and Engineering Nanyang Technological UniversitySingapore The College of Textile and Clothing Engineering Soochow UniversitySuzhouChina The College of Internet of Things Nanjing University of Posts and TelecomurunicationsNanjingChina

In Beyond the Fifth Generation(B5G)heterogeneous edge networks,numerous users are multiplexed on a channel or served on the same frequency resource block,in which case the transmitter applies coding and the receiver uses interference ***,uncoordinated radio resource allocation can reduce system throughput and lead to user inequity,for this reason,in this paper,channel allocation and power allocation problems are formulated to maximize the system sum rate and minimum user achievable *** the construction model is non-convex and the response variables are high-dimensional,a distributed Deep Reinforcement Learning(DRL)framework called distributed Proximal Policy Optimization(PPO)is proposed to allocate or assign ***,several simulated agents are trained in a heterogeneous environment to find robust behaviors that perform well in channel assignment and power ***,agents in the collection stage slow down,which hinders the learning of other ***,a preemption strategy is further proposed in this paper to optimize the distributed PPO,form DP-PPO and successfully mitigate the straggler *** experimental results show that our mechanism named DP-PPO improves the performance over other DRL methods.

关键词： B5G Heterogeneous edge networks PPO Channel assignment Power allocation Throughput