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On the Fundamental Limit of Multipath Matching Pursuit

IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING 2018年第5期12卷 916-927页

作者： Li, Haifeng Wang, Jian Yuan, Xin Henan Normal Univ Coll Math & Informat Sci Xinxiang 453007 Peoples R China Fudan Univ Sch Data Sci Shanghai 200433 Peoples R China Chinese Acad Sci Key Lab Quantum Opt Shanghai 200800 Peoples R China Bell Labs 600 Mt Ave Murray Hill NJ 07974 USA

D Multipath matching pursuit (MMP) is a recent extension of the orthogonal matching pursuit algorithm that recovers sparse signals with a tree-searching strategy. In this paper, we present a new analysis for the MMP algorithm using the restricted isometry property. Our result shows that if the sampling matrix A is an element of R-mxn satisfies the RIP of order K + L with isometry constant delta(K+L) < root L/K+L then the MMP accurately recovers any K-sparse signal x is an element of R-n from the samples y = Ax, where L is the number of child paths for each candidate of the algorithm. Moreover, through a counterexample, we show that the proposed bound is optimal in that the MMP algorithm may fail under delta(K+L) = root L/K+ L.

关键词： Multipath matching pursuit (MMP) orthogonal matching pursuit (OMP) restricted isometry property (RIP) sparse recovery

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Aphicidal activities of Amaryllidaceae alkaloids from bulbs of Lycoris radiata against Aphis citricola

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INDUSTRIAL CROPS AND PRODUCTS 2018年 123卷 372-378页

作者： Yan, He Xie, Na Zhong, Chenquan Su, Anqi Hui, Xiaoli Zhang, Xin Jin, Zhao Li, Zhipeng Feng, Juntao He, Jun Northwest A&F Univ Res & Dev Ctr Biorat Pesticides Yangling 712100 Shaanxi Peoples R China Northwest A&F Univ Engn & Res Ctr Biol Pesticide Shaanxi Prov Yangling 712100 Shaanxi Peoples R China Northwest A&F Univ Coll Plant Protect Yangling 712100 Shaanxi Peoples R China

Aphids are one of the most destructive and economically important pests of plants on earth, causing severe financial losses worldwide. The extensive and unscientific use of insecticides has resulted in a universal zooming insecticide resistance among aphids across regions and substantial detrimental influences on the environment. This study investigates the insecticidal activity of alkaloids from L. radiata against A. citricola. The crude extract of Lycoris radiate showed a remarkable aphicidal activity against A. citricola. Ten known amaryllidaceous alkaloids were obtained according to the bioassay-guided isolation. The structures of these known alkaloids were identified as amabiline (1), deoxydihydrotazettine (2), deoxytazettine (3), 3-epimacronine (4), galanthamine (5), 11-hydroxygalanthamine (6), N-allylnorgalanthamine (7), 11 beta-hydroxygalanthamine (8), lycorine (9) and colchicine (10). The results of aphicidal bioassay against A. citricola showed that compounds 1-9 exhibited considerable aphicidal activity with LD50 values of 67.44, 76.33, 78.30, 96.70, 17.47, 32.60, 4.92, 20.33, 70.41 ng/aphid. N-Allylnorgalanthamine (7) possessed the highest aphicial activity, which was comparable with the commercial pesticide methomyl (2.91 ng/aphid). The results of in vivo AChE assay revealed that N-allylnorgalanthamine showed an obvious inhibitory effect on AChE in A. citricola in a time- and dose-dependent manner. The in vitro inhibition of AChE activity by N-allylnorgalanthamine was remarkable with an IC50 value of 2.1 x 10(-8) M, which was 10(4) times stronger than the positive control methomyl with an IC50 value of 4.2 x 10(-4) M. Meanwhile, N-allylnorgalanthamine can lead to an increase of the activities of SOD and CAT. The present work comprises the first report on insecticidal action of Amaryllidaceae alkaloids. N-Allylnorgalanthamine displayed a significant inhibition on AChE in Aphis citricola both in vivo and vitro. The insecticidal L. radiata extracts can be

关键词： Lycoris radiate Amaryllidaceous alkaloids Aphicidal activity N-Allylnorgalanthamine AChE

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A novel wound dressing based on a Konjac glucomannan/silver nanoparticle composite sponge effectively kills bacteria and accelerates wound healing

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CARBOHYDRATE POLYMERS 2018年 183卷 70-80页

作者： Chen, Honglei Lan, Guangqian Ran, Luoxiao Xiao, Yang Yu, Kun Lu, Bitao Dai, Fangying Wu, Dayang Lu, Fei Southwest Univ Coll Text & Garments Chongqing 400715 Peoples R China Chongqing Engn Res Ctr Biomat Fiber & Modern Text Chongqing 400715 Peoples R China Guangdong Acad Agr Sci Sericulture & Agrifood Res Inst Guangzhou 510610 Guangdong Peoples R China

A novel Konjac glucomannan/silver nanoparticle (KGM/AgNP) composite sponge was successfully prepared via a simple 2-step method for biomedical applications as wound-healing materials. First, AgNPs were prepared with green deoxidizer egg white. Then, KGM powder was added to the AgNP solution and stirred vigorously, and the composite sponge was obtained by freeze-drying. The KGM/AgNP composite sponge showed excellent water absorption and water retention, and considerable mechanical properties. KGM/AgNP composite sponges displayed good antibacterial activity against test microorganisms. In vitro cytocompatibility testing showed that L929 cells could survive well in the presence of KGM/AgNPs, indicating that KGM/AgNPs have good cytocompatibility. Animal models showed that the KGM/AgNP composite sponges effectively accelerated wound healing, and histological findings showed that they promoted fibroblast growth and accelerated epithelialization. The experimental results showed that KGM/AgNP composite sponges have great potential in promoting wound healing.

关键词： Konjac glucomannan Silver nanoparticle Wound dressing Antibacterial activity Cytocompatibility Wound healing

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Study on the Different Replacing Groups of Trans-Paroxol for Enzymatic Resolution Using Molecular Simulations 3rd

Study on the Different Replacing Groups of Trans-Paroxol for...

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3rd International Conference on Applied Biotechnology (ICAB)

作者： Zhang, Chuan Jia, Yigang Xu, Chao Huang, He Hu, Yi Nanjin Tech Univ Coll Pharm State Key Lab Mat Oriented Chem Engn Nanjing 211816 Peoples R China

ISBN: (纸本)9789811048012;9789811048005

Trans-paroxol is an important key intermediate for paroxetine synthesis. Four different replacing groups of trans-paroxol on the kinetic resolution were studied to illuminate the mechanism of enzymatic catalysis using molecular simulations. Hydrogen bonds, hydrophobic interactions and the protein structure were analysed for enzyme-substrate complex. Results indicated that the formation of hydrogen bond, hydrophobic interactions and the distribution of substrate conformation in active site were the major forces which resulted in the diversity of enzymatic resolution. Electrostatic interactions and the stability of complex also played an important role in this reaction. This study will be quite useful for understanding the mechanism of enzymatic resolution and guiding to design the appropriate substrate for paroxetine synthesis. © Springer Nature Singapore Pte Ltd. 2018.

关键词： Enzymatic resolution Molecular docking Molecular dynamics simulations Paroxetine Trans-Paroxol

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Anterior Cruciate Ligament Reconstruction Surgery Navigation and Robotic Positioning System under X-rays

Anterior Cruciate Ligament Reconstruction Surgery Navigation...

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IEEE International Conference on Robotics and Biomimetics (ROBIO)

作者： Yang, Biao Hu, Lei Guo, Na Wang, Yuhan Liu, Hongsheng Han, Zhonghao Beihang Univ Robot Inst Beijing Peoples R China

ISBN: (纸本)9781728103778

With regards to visual and operating defects during routine arthroscopic anterior cruciate ligament surgery, this paper introduces an anterior cruciate ligament reconstruction surgery navigation and robotic positioning system that uses visual tracking sensors. The system employed intraoperative X-ray images to design feature point-based rapid spatial registration. Image rectification, intraoperative navigation, and robot-assisted positioning were used to complete assisted navigation and positioning of the anterior cruciate ligament tunnel in the femur and tibia. Following that, we carried out a detailed analysis of the errors produced by the navigation and positioning system, including image rectification errors, spatial registration errors, and visual tracking errors, and we carried out error simulations and experiments. We also carried out specimen bone experiments on the femur and tibia. Anteroposterior and lateral X-ray images were acquired each time and the location of the channel always fell on the anatomical end point of the anterior cruciate ligament, with an average time of 30 min. This system avoids surgical defects associated with conventional arthroscopy and solves the clinical problems of complex operation, small surgical field, and inaccurate positioning during anterior cruciate ligament surgery.

关键词： Errors

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A serine protease homologue Bombyx mori scarface induces a short and fat body shape in silkworm

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INSECT MOLECULAR BIOLOGY 2018年第3期27卷 319-332页

作者： Wang, R. -X. Tong, X. -L. Gai, T. -T. Li, C. -L. Qiao, L. Hu, H. Han, M. -J. Xiang, Z. -H. Lu, C. Dai, F. -Y. Southwest Univ State Key Lab Silkworm Genome Biol Key Lab Sericultural Biol & Genet Breeding Minist Agr Chongqing Peoples R China Chongqing Normal Univ Inst Entomol & Mol Biol Coll Life Sci Chongqing Peoples R China

Body shape is one of the most prominent and basic characteristics of any organism. In insects, abundant variations in body shape can be observed both within and amongst species. However, the molecular mechanism underlying body shape fine-tuning is very complex and has been largely unknown until now. In the silkworm Bombyx mori, the tubby (tub) mutant has an abnormal short fat body shape and the abdomen of tub larvae expands to form a fusiform body shape. Morphological investigation revealed that the body length was shorter and the body width was wider than that of the Dazao strain. Thus, this mutant is a good model for studying the molecular mechanisms of body shape fine-tuning. Using positional cloning, we identified a gene encoding the serine protease homologue, *** scarface (Bmscarface), which is associated with the tub phenotype. Sequence analysis revealed a specific 312-bp deletion from an exon of Bmscarface in the tub strain. In addition, recombination was not observed between the tub and Bmscarface loci. Moreover, RNA interference of Bmscarface resulted in the tub-like phenotype. These results indicate that Bmscarface is responsible for the tub mutant phenotype. This is the first study to report that mutation of a serine protease homologue can induce an abnormal body shape in insects.

关键词： body shape serine protease homologue positional cloning Bombyx mori

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Protein Separation Coacervation with Carboxymethyl Cellulose of Different Substitution Degree: Noninteracting Behavior of Bowman-Birk Chymotrypsin Inhibitor

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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018年第17期66卷 4439-4448页

作者： Li, Xingfei Long, Jie Hua, Yufei Chen, Yeming Kong, Xiangzhen Zhang, Caimeng Jiangnan Univ Sch Food Sci & Technol State Key Lab Food Sci & Technol 1800 Lihu Ave Wuxi 214122 Jiangsu Peoples R China

We first observed that protein/polysaccharide interaction exhibited noninteracting behavior which makes Bowman-Birk chymotrypsin inhibitor (BBI) always free of complexation, being separated from another protein with similar isoelectric points, Kunitz trypsin inhibitor (KTI). Turbidity titrations showed that the electrostatic attractions were much stronger between KTI/BBI (KBi) and carboxymethyl cellulose of higher substitution degree. Unchanged chymotrypsin inhibitory activity (CIA) indicated that BBI had negligible contribution to protein recovery and trypsin inhibitory activity (TIA). Tricine-SDS-PAGE revealed that, at r = 20:1-2:1, unbound BBI was left in the supernatant when bound KTI transferred into precipitates, even if there was excess negative charge. Thus, purified KTI or BBI was achieved easily at the given conditions. The noninteracting behavior of BBI was further confirmed by ITC, where the binding enthalpy of BBI to CMC was negligible compared with the high binding affinity (K-b) of KTI. This work will be beneficial to protein purification based on protein polysaccharide coacervation.

关键词： protein separation carboxymethyl cellulose KBi isothermal titration calorimetry binding affinity

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Identification of Morus notabilis MADS-box genes and elucidation of the roles of MnMADS33 during endodormancy

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SCIENTIFIC REPORTS 2018年第1期8卷 1-16页

作者： Luo, Yiwei Li, Hongshun Xiang, Zhonghuai He, Ningjia Southwest Univ State Key Lab Silkworm Genome Biol Chongqing 400715 Peoples R China

The MADS-box genes encode transcriptional regulators with various functions especially during floral development. A total of 54 putative Morus notabilis MADS-box genes (MnMADSs) were identified and phylogenetically classified as either type I (17 genes) or type II (37 genes). The detected genes included three FLOWERING LOCUS C-like (MnFLC-like) genes, MnMADS33, MnMADS50, and MnMADS7. MnFLC-like proteins could directly or indirectly repress promoter activity of the mulberry FLOWERING LOCUS T-like (MnFT) gene. Transgenic Arabidopsis thaliana overexpressing MnFLC-like genes exhibited delayed flowering and down-regulated expression of FT and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1). The gene expression analyses in floral bud indicated that MnMADS33 expression increased, while MnFT expression decreased during the induction of dormancy in response to cold conditions. Dormancy release resulted in the down-regulation of MnMADS33 expression and the upregulation of MnFT expression. Furthermore, abscisic acid promoted the transcription of MnMADS33 and MnFT, although the expression level of MnFT gradually decreased. These results are consistent with the hypothesis that MnMADS33 negatively regulated the expression of MnFT to repress dormancy release and flowering in mulberry. This study may be relevant for future investigations regarding the effects of MnMADS genes on mulberry flowering development.

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Deep-stacked auto encoder for liver segmentation 12th

Deep-stacked auto encoder for liver segmentation

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12th Chinese conference on Advances in Image and Graphics technologies, IGTA 2017

作者： Ahmad, Mubashir Yang, Jian Ai, Danni Qadri, Syed Furqan Wang, Yongtian Beijing Engineering Research Center of Mixed Reality and Advanced Display School of Optics and Electronics Beijing Institute of Technology Beijing China School of Computer Science and Technology Beijing Institute of Technology Beijing China

ISBN: (纸本)9789811073885

Deep learning methods have been successfully applied to feature learning in medical applications. In this paper, we proposed a Deep Stacked Auto-Encoder (DSAE) for liver segmentation from CT images. The proposed method composes of three major steps. First, we learned the features with unlabeled data using the auto encoder. Second, these features are fine-tuned to classify the liver among other abdominal organs. Using this technique we got promising classification results on 2D CT data. This classification of the data helps to segment the liver from the abdomen. Finally, segmentation of a liver is refined by post processing method. We focused on the high accuracy of the classification task because of its effect on the accuracy of a better segmentation. We trained the deep stacked auto encoder (DSAE) on 2D CT images and experimentally shows that this method has high classification accuracy and can speed up the clinical task to segment the liver. The mean DICE coefficient is noted to be 90.1% which is better than the state of art methods. © Springer Nature Singapore Pte Ltd. 2018.

关键词： Classification (of information)

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Oral administration of chondroitin sulfate-functionalized nanoparticles for colonic macrophage-targeted drug delivery

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CARBOHYDRATE POLYMERS 2019年 223卷 115126页

作者： Zhang, Xueqing Ma, Ya Ma, Lijun Zu, Menghang Song, Heliang Xiao, Bo Southwest Univ Sch Mat & Energy State Key Lab Silkworm Genome Biol Chongqing 400715 Peoples R China Southwest Univ Chongqing Key Lab Soft Matter Mat Chem & Funct Mf Sch Mat & Energy Chongqing 400715 Peoples R China Southwest Univ Coll Biotechnol Key Lab Sericultural Biol & Genet Breeding Minist Agr & Rural Affairs Chongqing 400715 Peoples R China Georgia State Univ Ctr Diagnost & Therapeut Atlanta GA 30303 USA

Orally targeted delivery of anti-inflammatory drugs to macrophages has attracted great attention for minimizing the symptoms of ulcerative colitis (UC). In this investigation, we encapsulated curcumin (CUR) into polymeric nanoparticles (NPs), and conjugated chondroitin sulfate (CS) to their surfaces. The resulting CS-NPs had an average diameter of 281 nm, monodisperse size distribution and negatively charged surface. Cell experiments indicated that these NPs showed excellent biocompatibility, and yielded significantly higher cell internalization efficiency in Raw 264.7 macrophages than their counterparts (carboxymethyl cellulose-functionalized CUR-encapsulated NPs, CUL-NPs). Moreover, CS-NPs exhibited a dramatically stronger capacity to inhibit the secretion of the major pro-inflammatory cytokines from lipopolysaccharide-stimulated macrophages compared with CUL-NPs. In vivo experiments revealed that oral administration of chitosan/alginate hydrogel embedding CS-NPs achieved better therapeutic outcomes against UC comparied with CUL-NPs. Collectively, our results demonstrated that CS-NP-embedded hydrogel held a great promise to be developed as a macrophage-targeted drug delivery system for UC treatment.

关键词： Oral administration Chondroitin sulfate Nanotherapeutic Ulcerative colitis Macrophage-targeted drug delivery

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