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A Novel Regenerated Silk Fibroin-based Hydrogels with Magnetic and Catalytic Activities

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Chinese Journal of Polymer Science 2017年第4期35卷 515-523页

作者： kun-yuan luo 邵正中 State Key Laboratory of Molecular Engineering of Polymers Laboratory of Advanced Materials and Department of Macromolecular Science Fudan University Shanghai 200433 China

A simple and facile synthetic methodology for fabricating the regenerated silk fibroin （RSF）-based hydrogel which consisted of the in situ generated magnetic ferriferous oxide （Fe304） was developed. Using the co-precipitation of Fe2＋ and Fe3＋ within the RSF-based hydrogel with 90% RSF and 10% HPMC （hydroxypropyl methyl cellulose）, the as-prepared RSF/Fe304 hydrogel not only showed high strength of saturation magnetization, but also exhibited excellent catalytic activities. For example, with the assistant of 3,3＇,5,5＇-tetramethylbenzidine （TMB）, the RSF/Fe304 hydrogel could detect H202 at a concentration as low as 1 x 10-6 mol.L-1 In addition, the catalytic activities were able to be maintained for a long term under various conditions. These findings suggest that the RSF-based materials can be endowed with interesting properties, and have great potential for the applications in the fields of biotechnology and environmental chemistry.

关键词： Natural polymer Silk Hydrogel Nanoparticle Magnetic and catalytic activity

Storage and repair bandwidth tradeoff for distributed storage systems with clusters and separate nodes

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Science China(Information Sciences) 2018年第10期61卷 63-79页

作者： Jingzhao WANG Tinghan WANG yuan luo Department of Computer Science and Engineering Shanghai Jiao Tong University

The optimal tradeoff between node storage and repair bandwidth is an important issue for distributed storage systems(DSSs). For realistic DSSs with clusters, while repairing a failed node, downloading more data from intra-cluster nodes than from cross-cluster nodes is effective. Therefore, differentiating the repair bandwidth from intra-cluster and cross-cluster is useful. For cluster DSSs, the tradeoff is considered with special repair assumptions where all alive nodes are used for repairing a failed node. In this paper, we investigate the optimal tradeoff for the cluster DSSs under more general storage/repair parameters. Furthermore, we propose a regenerating code construction strategy that achieves the points in the optimal tradeoff curve for the cluster DSSs with specific parameters as a numerical example. Moreover, we consider the influence of separate nodes for the tradeoff for the DSSs with clusters and separated nodes.

关键词： distributed storage system cluster separate node repair bandwidth communication cost

Adhesive properties study on the interfaces of AlN and metal of Pd,Ag and Cu

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Science China(Technological Sciences) 2011年第1期54卷 11-14页

作者： CAI XueMei luo yuan College of Electronic Engineering Chongqing University of Posts and Telecommunications Chongqing 400065 China

A1N is used as high power LED package material because of its excellent thermal conductivity. But its poor adhesive with metal is not compatible with the later processing sequence. The properties of the bonding between the deposited palladium, silver, copper and the clean Al-terminated （0001） surface of wurtzite AIN are investigated by using the density-functional the- ory. The results show that the sites of deposited metal atoms on N site are more stable than that on A1 site. Relaxations are found at all the studied interfaces. The bonding energies of Pd/A1N, Ag/A1N and Cu/A1N are respectively 2.75, 1.98, 2.26 eV. Hybridizations of s orbit and p orbit of the deposited metal atoms are observed, which contributes to the bonding energy of interface. The moving to lower energy state of the d orbit and the easier transfer of electrons to semi-empty d orbit in the case of deposited Pd results in the higher bonding energy of Pd/A1N interface.

关键词： palladium silver copper AIN clean Al-terminated (0001) surface density-functional theory

Storage and repair bandwidth tradeoff for heterogeneous cluster distributed storage systems

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Science China(Information Sciences) 2020年第2期63卷 131-145页

作者： Jingzhao WANG yuan luo Kenneth W.SHUM Department of Computer Science and Engineering Shanghai Jiao Tong University Institute of Network Coding The Chinese University of Hong Kong

The storage and repair bandwidth tradeoff is an important issue in distributed storage systems(DSSs) where large scale data are stored in multiple nodes with erasure coding to ensure reliability. There are lots of studies on the DSS model with multiple clusters where the repair bandwidths from intra-cluster and cross-cluster nodes are differentiated to improve repair efficiency based on the realistic network topological structures. At the same time, separate nodes are also prevalent due to the variety of practical networks, but the work on the cluster DSS model with multiple separate nodes is insufficient, which is a main motivation of this paper. We formulate the tradeoff bound between storage repair bandwidth for a heterogeneous DSS model consisting of clusters and separate nodes by analyzing the min-cuts of heterogeneous information flow graphs corresponding to the orders of failed nodes. Additionally, the tradeoff bounds are investigated in multiple aspects when the repair bandwidth constraints and the amount of separate nodes vary, ***, a class of regenerating codes are illustrated to achieve the tradeoff in the heterogeneous cases.

关键词： distributed storage system cluster separate node repair bandwidth information flow graph

基于双目视觉和改进YOLOv8n的火灾检测及测距方法

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陕西科技大学学报 2025年第1期43卷 152-160页

作者：刘振董绍江罗家元孙世政潘学娇重庆交通大学机电与车辆工程学院重庆400074

针对火灾检测出现的漏检误检、模型参数量大及定位困难的问题,基于双目视觉和改进YOLOv8n提出了一种轻量化火灾检测及测距方法.通过双目相机拍摄图片,使用改进的检测算法YOLOv8n-AEM和现有的测距算法SGBM进行检测和测距.首先,在主干网... 详细信息

针对火灾检测出现的漏检误检、模型参数量大及定位困难的问题,基于双目视觉和改进YOLOv8n提出了一种轻量化火灾检测及测距方法.通过双目相机拍摄图片,使用改进的检测算法YOLOv8n-AEM和现有的测距算法SGBM进行检测和测距.首先,在主干网络中引入可变核卷积AKConv和EMA注意力机制,通过构建不规则卷积核有效提取火灾的特征;然后,在颈部网络中构建C2f-SCConv模块,通过特征重组降低模型参数,提高检测速度;其次,基于最小点距离改进损失函数,解决火源与光源重叠导致的漏检与误检问题;最后,增加小目标检测头,提高对小火苗的检测能力.实验结果表明,改进后的检测算法P、R、mAP分别为83.6%、76.4%、83.6%,分别提高了2.5%、3.6%、4.8%;参数量和模型大小分别为2.54 M和5.1 MB,分别降低了15.3%和15%;测距精度误差不超过2.5%,证明改进的方法能准确完成火灾的检测及测距.

关键词：火灾检测双目视觉测距 YOLOv8n 轻量化

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Intelligent wheelchair system based on s EMG and head gesture

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The Journal of China Universities of Posts and Telecommunications 2015年第2期22卷 74-80,95页

作者： Zhang Yi Feng Xiaolin luo yuan National Engineering Research and Development Center for Information Accessibility Chongqing University of Posts and Telecommunications

Because the single channel surface electromyographic （sEMG） signals easily caused a complex operation during the real-time operation, an intelligent wheelchair system based on sEMG and head gesture was proposed in this paper. A distributed parallelly decision fusion algorithm fused classification results of the two signals to form a final judgment. After sEMG was decomposed by wavelet packet, feature information of some subspace was weaken, because subspace dimension was very large. To solve the problem, the paper proposed an improved wavelet packet decomposition algorithm, which extracted sample entropy from four subspaces of improved wavelet packet decomposition and took it as the feature information. Experimental results show that the intelligent wheelchair system based on sEMG and head gesture has not only a simple operation and shorter operating time, but also a better stability and security.

关键词： sEMG head gesture, decision fusion, improved wavelet packet, intelligent wheelchair

Immobilization of self-assembled pre-dispersed nano-TiO_2 onto montmorillonite and its photocatalytic activity

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Journal of Environmental Sciences 2015年第6期27卷 108-117页

作者： Tingting Zhang yuan luo Bing Jia Yan Li Lingling yuan Jiang Yu Research Group of Environmental Catalysis & Separation Process College of Chemical Engineering Beijing University of Chemical Technology

The immobilization of pre-dispersed Ti O2 colloids onto the external surface of the clay mineral montmorillonite（Mt） was accomplished and regulated via a self-assembly method employing the cationic surfactant cetyltrimethylammonium bromide（CTAB）. The role of CTAB in the synthesis process was investigated by preparing a series of Ti O2-CTAB-Mt composites（TCM） with various CTAB doses. The results indicated that a uniform and continuous Ti O2 film was deposited on the external surface of montmorillonite in the composite synthesized with 0.1 wt.% of CTAB, and the TCM nano-composites showed much higher values for specific surface area, average pore size and pore volume than the raw montmorillonite clay. Then, the formed TCM materials were applied in photocatalytic degradation of 2,4-dichlorophenol（2,4-DCP） in aqueous solution. The degradation efficiency reached as high as 94.7%. Based on the degradation intermediates benezoquinone, fumaric acid and oxalic acid identified by LC-MS analysis, a mechanism for the photocatalytic oxidation of 2,4-DCP on Ti O2/Mt nano-composites is proposed.

关键词： Ti O2/Mt composite CTAB Immobilization Photocatalysis

Performance-weighted-voting model:An ensemble machine learning method for cancer type classification using whole-exome sequencing mutation

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Quantitative Biology 2020年第4期8卷 347-358页

作者： Yawei Li yuan luo Department of Preventive Medicine Northwestern UniversityFeinberg School of MedicineChicagoIL 60611USA

Background:With improvements in next-generation DNA sequencing technology,lower cost is needed to collect genetic *** machine learning techniques can be used to help with cancer analysis and ***:We developed an ensemble machine learning system named performance-weighted-voting model for cancer type classification in 6,249 samples across 14 cancer *** ensemble system consists of five weak classifiers(logistic regression,SVM,random forest,XGBoost and neural networks).We first used cross-validation to get the predicted results for the five *** weights of the five weak classifiers can be obtained based on their predictive performance by solving linear regression *** final predicted probability of the performance-weighted-voting model for a cancer type can be determined by the summation of each classifier's weight multiplied by its predicted ***:Using the somatic mutation count of each gene as the input feature,the overall accuracy of the performance-weighted-voting model reached 71.46%,which was significantly higher than the five weak classifiers and two other ensemble models:the hard-voting model and the soft-voting *** addition,by analyzing the predictive pattern of the performance-weighted-voting model,we found that in most cancer types,higher tumor mutational burden can improve overall ***:This study has important clinical significance for identifying the origin of cancer,especially for those where the primary cannot be *** addition,our model presents a good strategy for using ensemble systems for cancer type classification.

关键词： cancer type classification ensemble method performance-weighted-voting model linear regression single-nucleotide polymorphism

Intestinal glucagon-like peptide-1:A new regulator of impaired counterregulatory responses to hypoglycemia in type 1 diabetes mellitus

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World Journal of Diabetes 2025年第1期16卷 217-221页

作者： Le-Rong Liu yuan-yuan luo Pei-Zhu Su Cong Zhang Zhao-Tao Li Department of Endocrinology and Metabolism Nanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Endocrinology Chongqing University Three Gorges HospitalChongqing 404100China Chongqing Municipality Clinical Research Center for Endocrinology and Metabolic Diseases Chongqing University Three Gorges HospitalChongqing 404100China Department of Endocrinology The Second Affiliated HospitalChongqing Medical UniversityChongqing 400013China Department of Gastroenterology The First People's Hospital of FoshanFoshan 528000Guangdong ProvinceChina

In this article,we review the study by Jin et al,which examined the role of intestinal glucagon-like peptide-1(GLP-1)in counterregulatory responses to hypoglycemia in patients with type 1 diabetes mellitus(T1DM).With the global rise of T1DM,there is an increased burden on society and healthcare *** to insulin therapy and islet dysfunction,T1DM patients are highly vulnerable to severe hypoglycemia,a leading cause of *** healthy individuals,counterregulatory mechanisms restore blood glucose during hypoglycemia,but repeated episodes impair these *** et al demonstrated that overexpression of GLP-1 attenuates the sympathetic-adrenal reflex and disrupts the secretion of counterregulatory hormones such as glucagon during hypoglycemia,leading to counterregulatory *** findings highlight the critical role of GLP-1 in the impaired counterregulatory response to hypoglycemia in T1DM patients and provide new insights into the potential application of GLP-1-related therapies in T1DM patients.

关键词： Glucagon-like peptide-1 Impaired counterregulation Type 1 diabetes mellitus Sympathetic-adrenal reflex Glucagon