44 results on '"Xiangyu Gong"'
Search Results
2. Evolutionary and Functional Analysis of Coagulase Positivity among the Staphylococci
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Amy C. Pickering, Gonzalo Yebra, Xiangyu Gong, Mariya I. Goncheva, Bryan A. Wee, Alison C. MacFadyen, Lukas F. Muehlbauer, Joana Alves, Robyn A. Cartwright, Gavin K. Paterson, and J. Ross Fitzgerald
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Microbiology ,QR1-502 - Abstract
The ability of some species of staphylococci to promote coagulation of plasma is a key pathogenic and diagnostic trait. Here, we provide a comprehensive analysis of the coagulase positivity of the staphylococci and its evolutionary genetic basis.
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- 2021
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3. Purification and in situ immobilization of papain with aqueous two-phase system.
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Mingliang Li, Erzheng Su, Pengyong You, Xiangyu Gong, Ming Sun, Diansheng Xu, and Dongzhi Wei
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Medicine ,Science - Abstract
Papain was purified from spray-dried Carica papaya latex using aqueous two-phase system (ATPS). Then it was recovered from PEG phase by in situ immobilization or preparing cross-linked enzyme aggregates (CLEAs). The Plackett-Burman design and the central composite design (CCD) together with the response surface methodology (RSM) were used to optimize the APTS processes. The highly purified papain (96-100%) was achieved under the optimized conditions: 40% (w/w) 15 mg/ml enzyme solution, 14.33-17.65% (w/w) PEG 6000, 14.27-14.42% (w/w) NaH2PO4/K2HPO4 and pH 5.77-6.30 at 20°C. An in situ enzyme immobilization approach, carried out by directly dispersing aminated supports and chitosan beads into the PEG phase, was investigated to recover papain, in which a high immobilization yield (>90%) and activity recovery (>40%) was obtained. Moreover, CLEAs were successfully used in recovering papain from PEG phase with a hydrolytic activity hundreds times higher than the carrier-bound immobilized papain.
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- 2010
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4. Bifrost: Extending RoCE for Long Distance Inter-DC Links.
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Peiwen Yu, Feiyang Xue, Chen Tian 0001, Xiaoliang Wang 0001, Yanqing Chen, Tao Wu, Lei Han, Zifa Han, Bingquan Wang, Xiangyu Gong, Wanchun Dou, and Guihai Chen
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- 2023
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5. Self-assembly of mesoscale collagen architectures and applications in 3D cell migration
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Chang Liu, Ryan Y. Nguyen, Gabriela A. Pizzurro, Xingjian Zhang, Xiangyu Gong, Alejandro Rossello Martinez, and Michael Mak
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Biomaterials ,Biomedical Engineering ,General Medicine ,Molecular Biology ,Biochemistry ,Biotechnology - Abstract
3D in vitro tumor models have recently been investigated as they can recapitulate key features in the tumor microenvironment. Reconstruction of a biomimetic scaffold is critical in these models. However, most current methods focus on modulating local properties, e.g. micro- and nano-scaled topographies, without capturing the global millimeter or intermediate mesoscale features. Here we introduced a method for modulating the collagen I-based extracellular matrix structure by disruption of fibrillogenesis and the gelation process through mechanical agitation. With this method, we generated collagen scaffolds that are thickened and wavy at a larger scale while featuring global softness. Thickened collagen patches were interconnected with loose collagen networks, highly resembling collagen architecture in the tumor stroma. This thickened collagen network promoted tumor cell dissemination. In addition, this novel modified scaffold triggered differences in morphology and migratory behaviors of tumor cells. Altogether, our method for altered collagen architecture paves new ways for studying in detail cell behavior in physiologically relevant biological processes. STATEMENT OF SIGNIFICANCE: Tumor progression usually involves chronic tissue damage and repair processes. Hallmarks of tumors are highly overlapped with those of wound healing. To mimic the tumor milieu, collagen-based scaffolds are widely used. These scaffolds focus on modulating microscale topographies and mechanics, lacking global architecture similarity compared with in vivo architecture. Here we introduced one type of thick collagen bundles that mimics ECM architecture in human skin scars. These thickened collagen bundles are long and wavy while featuring global softness. This collagen architecture imposes fewer steric restraints and promotes tumor cell dissemination. Our findings demonstrate a distinct picture of cell behaviors and intercellular interactions, highlighting the importance of collagen architecture and spatial heterogeneity of the tumor microenvironment.
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- 2023
6. Tunable Mesoscopic Collagen Island Architectures Modulate Stem Cell Behavior (Adv. Mater. 16/2023)
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Ryan Y. Nguyen, Aidan T. Cabral, Alejandro Rossello‐Martinez, Alessandro Zulli, Xiangyu Gong, Qiuting Zhang, Jing Yan, and Michael Mak
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Published
- 2023
7. An Organotypic Mammary Duct Model Capturing Matrix Mechanics-Dependent Ductal Carcinoma In Situ Progression
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Xiangyu Gong, Jason I. Herschkowitz, Jonathan Kulwatno, Rebecca Sinnott DeVaux, and Kristen L. Mills
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In situ ,Pathology ,medicine.medical_specialty ,business.industry ,Biomedical Engineering ,Mammary duct ,Bioengineering ,Abnormal cell ,Ductal carcinoma ,medicine.disease ,Biochemistry ,female genital diseases and pregnancy complications ,In vitro model ,Biomaterials ,Breast cancer ,medicine.anatomical_structure ,medicine ,Stage (cooking) ,skin and connective tissue diseases ,business ,Duct (anatomy) - Abstract
Ductal carcinoma in situ (DCIS) is a precancerous stage breast cancer, where abnormal cells are contained within the duct, but have not invaded into the surrounding tissue. However, only 30–40% of ...
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- 2021
8. Robust Storage of Chinese Language in a Pool of Small Single-Stranded DNA Rings and Its Facile Reading-Out
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Hui Chen, Hongfang Liu, Xiangyu Gong, Ran An, Jing Wang, Jiaojiao Tao, Wang Chenru, Hongyu Wang, Xingguo Liang, Makoto Komiyama, Ning Huang, Taiwei Yang, and Zhihao Song
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business.industry ,Chemistry ,media_common.quotation_subject ,Information technology ,Archival storage ,General Chemistry ,World Wide Web ,chemistry.chemical_compound ,Reading (process) ,Chinese language ,Nanopore sequencing ,business ,DNA ,media_common - Abstract
Archival storage in DNA is one of the most challenging themes in rapidly growing information technology. In addition, its practical applications are more difficult due to complicated data analysis,...
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- 2021
9. Growth of tumor emboli within a vessel model reveals dependence on the magnitude of mechanical constraint
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Mihaela Skobe, Jamie Gearhart, Xiangyu Gong, Matthew Getzin, Jonathan Kulwatno, Nora Herzog, and Kristen L. Mills
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Force generation ,Cylindrical geometry ,Materials science ,Biophysics ,Context (language use) ,Breast Neoplasms ,Matrix (biology) ,Biochemistry ,Metastasis ,Spheroids, Cellular ,Lymphatic vessel ,medicine ,Humans ,cardiovascular diseases ,Elastic modulus ,Lymphatic Vessels ,Chemistry ,Spheroid ,Stiffness ,Neoplastic Cells, Circulating ,medicine.disease ,Tumor recurrence ,medicine.anatomical_structure ,Tumor progression ,cardiovascular system ,Female ,medicine.symptom ,Biomedical engineering - Abstract
Tumor emboli – aggregates of tumor cell within vessels – pose a clinical challenge as they are associated with increased metastasis and tumor recurrence. When growing within a vessel, tumor emboli are subject to a unique mechanical constraint provided by the tubular geometry of the vessel. Current models of tumor emboli use unconstrained multicellular tumor spheroids, which neglect this mechanical interplay. Here, we modelled a lymphatic vessel as a 200 μm-diameter channel in either a stiff or soft, bioinert agarose matrix, and we modelled colon or breast cancer tumor emboli with aggregates of HCT116 or SUM149PT cells, respectively. The stiff vessel model constrained the tumor emboli to the cylindrical geometry, which led to continuous growth of the emboli, in contrast to the growth plateau that unconstrained spheroids exhibit. Emboli morphology in the soft vessel model, however, was dependent on the magnitude of mechanical mismatch between the vessel matrix and the cell aggregates. In general, when the elastic modulus of the vessel was greater than the emboli (Eves / Eemb > 1), the emboli were constrained to grow within the vessel geometry, and when the elastic modulus of the vessel was less than the emboli (0 < Eves / Eemb < 1), the emboli bulged into the matrix. Inhibitors of myosin-related force generation decreased the elastic modulus and/or increased the stress relaxation of the tumor cell aggregates, effectively increasing the mechanical mismatch. The increased mechanical mismatch after drug treatment was correlated with increased confinement of tumor emboli growth along the vessel, which may translate to increased tumor burden due to the increased tumor volume within the diffusion distance of nutrients and oxygen.INSIGHT BOXThe growth of tumor emboli—aggregates of tumor cells within vessels—is associated with aggressive cancer progression and metastasis. Models of their growth have not taken into account their biomechanical context, where radial expansion is constrained, but lengthwise expansion is free in the vessel. Here, we modelled the vessel geometry with a cylindrical microchannel in a hydrogel. In contrast to unconstrained or fully embedded aggregates, vessel-like constraint promotes growth of emboli in our model. The growth advantage is increased when the matrix is stiffened or actomyosin contractility weakened, both of which effectively increase the magnitude of mechanical constraint. This study sheds light on increased tumor burden in vessel-based growth and indicates a need to study tumor progression in similar environments.
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- 2021
10. Novel, high-throughput collagen-based bioprinting for tissue engineering
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Xiangyu Gong, Zhang Wen, Sein Lee, and Michael Mak
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Biophysics - Published
- 2023
11. A microfluidic-informatics assay for quantitative physical occlusion measurement in sickle cell disease
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Xingjian Zhang, Trevor Chan, Judith Carbonella, Xiangyu Gong, Noureen Ahmed, Chang Liu, Israel Demandel, Junqi Zhang, Farzana Pashankar, and Michael Mak
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Informatics ,Microfluidics ,Hardware_INTEGRATEDCIRCUITS ,Biomedical Engineering ,Humans ,Bioengineering ,General Chemistry ,Anemia, Sickle Cell ,Hardware_ARITHMETICANDLOGICSTRUCTURES ,Biochemistry - Abstract
Sickle cell disease (SCD) is a genetic condition that causes abnormalities in hemoglobin mechanics. Those affected are at high risk of vaso-occlusive crisis (VOC), which can induce life-threatening symptoms. The development of measurements related to vaso-occlusion facilitates the diagnosis of the patient's disease state. To complement existing readouts, we design a microfluidic-informatics analytical system with varied confined geometries for the quantification of sickle cell disease occlusion. We detect an increase in physical occlusion events in the most severe hemoglobin SS group. We use bioinformatics and modeling to quantify the
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- 2022
12. Rapid fabrication of collagen bundles mimicking tumor-associated collagen architectures
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Xiangyu Gong, Kristen L. Mills, and Jonathan Kulwatno
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Tumor microenvironment ,Stromal cell ,Chemistry ,Biomedical Engineering ,Hydrogels ,General Medicine ,Matrix (biology) ,Biochemistry ,Collagen Type I ,Extracellular Matrix ,Biomaterials ,Connective Tissue ,In vivo ,Tumor progression ,Nanofiber ,Self-healing hydrogels ,Reticular connective tissue ,Biophysics ,Collagen ,Molecular Biology ,Biotechnology - Abstract
Stromal collagen is upregulated surrounding a solid tumor and presents as dense, thick, linearized, and aligned bundles. The collagen bundles are continually remodeled during tumor progression, and their orientation with respect to the tumor boundary has been correlated with invasive state. Currently, reconstituted-collagen gels are the standard in vitro tumor cell-extracellular matrix interaction model. The reticular, dense, and isotropic nanofiber (~900 nm-diameter, on average) gels do not, however, recapitulate the in vivo structural features of collagen bundling and alignment. Here, we present a rapid and simple method to fabricate bundles of collagen type I, whose average thickness may be varied between about 4 μm and 9 μm dependent upon diluent temperature and ionic strength. The durability and versatility of the collagen bundles was demonstrated with their incorporation into two in vitro models where the thickness and alignment of the collagen bundles resembled various in vivo arrangements. First, collagen bundles aligned by a microfluidic device elicited cancer cell contact guidance and enhanced their directional migration. Second, the presence of the collagen bundles in a bio-inert agarose hydrogel was shown to provide a route for cancer cell outgrowth. The unique structural features of the collagen bundles advance the physiological relevance of in vitro collagen-based tumor models for accurately capturing tumor cell-extracellular matrix interactions. Statement of significance Collagen in the tumor microenvironment is upregulated and remodeled into dense, thick, and aligned bundles that are associated with invasive state. Current collagen-based in vitro models are based on reticular, isotropic nanofiber gels that do not fully recapitulate in vivo tumor stromal collagen. We present a simple and robust method of rapidly fabricating cell-scale collagen bundles that better mimic the remodeled collagen surrounding a tumor. Interacting with the bundles, cancer cells exhibited drastically different phenotypic behaviors, compared to nanofiber scaffolds. This work reveals the importance of microscale architecture of in vitro tumor models. The collagen bundles provide physiologically relevant collagen morphologies that may be easily incorporated into existing models of tumor cell-extracellular matrix interactions.
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- 2020
13. Fat reducing effects of
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Luyi, Ye, Xiaolin, Wang, Tomonobu, Konno, Xiangyu, Gong, Hao, Ding, Hua, Yan, Zai-Si, Ji, and Enuo, Liu
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Male ,Plant Leaves ,Plant Extracts ,Humans ,Female ,Nelumbo ,Overweight - Abstract
The leaf of
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- 2021
14. Ca2+ sensor-mediated ROS scavenging suppresses rice immunity and is exploited by a fungal effector
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Yiwen Deng, Guo-Liang Wang, Guiquan Zhang, Jin Chen, Xiangyu Gong, Jiyun Liu, Didier Tharreau, Shenghan Xie, Huizhong Chang, Jiaxing Yue, Yang He, Keran Zhai, Xin Yin, Jianlong Xu, Yue Wu, Bingxiao Yan, Yifeng Huang, Xiangbin Zhong, Ertao Wang, Mingjun Gao, Zuhua He, Xiaoyuan Li, Weibing Yang, CAS Center for Excellence in Molecular Plant Sciences (CEMPS), Chinese Academy of Sciences [Beijing] (CAS), ShanghaiTech University [Shanghai], Sun Yat-sen University Cancer Center (SYSUCC), Sun Yat-Sen University [Guangzhou] (SYSU), Chinese Academy of Agricultural Sciences (CAAS), South China Agricultural University (SCAU), Plant Health Institute of Montpellier (UMR PHIM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Université de Montpellier (UM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Département Systèmes Biologiques (Cirad-BIOS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Ohio State University [Columbus] (OSU), National Natural Science Foundation of China (32088102, 31930090, and 31720103913 and 31801718 .), the Chinese Academy of Sciences Strategic Priority Research Program (XDB27040201 and XDB27030107 .), the National Key Research and Development Program of China (2016YFD0100600), the Sino-German Center for Research Promotion (M-0275), the Science and Technology Commission of ShanghaiMunicipality (19391900300), China Postdoctoral Science Foundation (2019M650036, 2018M640425)., and the National Postdoctoral Program for Innovative Talents (BX201700269)
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pyriculariose du riz ,F60 - Physiologie et biochimie végétale ,Homéostasie ,Plant Immunity ,Virulence ,Oryza sativa ,Plant disease resistance ,Xanthomonas oryzae ,General Biochemistry, Genetics and Molecular Biology ,Immune system ,Maladie des plantes ,Immunity ,Effecteur moléculaire ,H20 - Maladies des plantes ,chemistry.chemical_classification ,Reactive oxygen species ,biology ,Effector ,Rhizoctonia solani ,food and beverages ,Résistance aux maladies ,Catalase ,dérivé réactif de l'oxygène ,Cell biology ,Physiologie végétale ,[SDV.BV.PEP]Life Sciences [q-bio]/Vegetal Biology/Phytopathology and phytopharmacy ,chemistry ,biology.protein ,Immunité - Abstract
International audience; Plant immunity is activated upon pathogen perception and often affects growth and yield when it is constitutively active. How plants fine-tune immune homeostasis in their natural habitats remains elusive. Here, we discover a conserved immune suppression network in cereals that orchestrates immune homeostasis, centering on a Ca2+-sensor, RESISTANCE OF RICE TO DISEASES1 (ROD1). ROD1 promotes reactive oxygen species (ROS) scavenging by stimulating catalase activity, and its protein stability is regulated by ubiquitination. ROD1 disruption confers resistance to multiple pathogens, whereas a natural ROD1 allele prevalent in indica rice with agroecology-specific distribution enhances resistance without yield penalty. The fungal effector AvrPiz-t structurally mimics ROD1 and activates the same ROS-scavenging cascade to suppress host immunity and promote virulence. We thus reveal a molecular framework adopted by both host and pathogen that integrates Ca2+ sensing and ROS homeostasis to suppress plant immunity, suggesting a principle for breeding disease-resistant, high-yield crops.
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- 2021
15. Cytoskeletal dynamics regulates stromal invasion behavior of distinct liver cancer subtypes
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Ryan Y, Nguyen, Hugh, Xiao, Xiangyu, Gong, Alfredo, Arroyo, Aidan T, Cabral, Tom T, Fischer, Kaitlin M, Flores, Xuchen, Zhang, Marie E, Robert, Barbara E, Ehrlich, and Michael, Mak
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Liver Neoplasms ,Humans ,Hydrogels ,Cytoskeleton ,Cell Line - Abstract
Drug treatment against liver cancer has limited efficacy due to heterogeneous response among liver cancer subtypes. In addition, the functional biophysical phenotypes which arise from this heterogeneity and contribute to aggressive invasive behavior remain poorly understood. This study interrogated how heterogeneity in liver cancer subtypes contributes to differences in invasive phenotypes and drug response. Utilizing histological analysis, quantitative 2D invasion metrics, reconstituted 3D hydrogels, and bioinformatics, our study linked cytoskeletal dynamics to differential invasion profiles and drug resistance in liver cancer subtypes. We investigated cytoskeletal regulation in 2D and 3D culture environments using two liver cancer cell lines, SNU-475 and HepG2, chosen for their distinct cytoskeletal features and invasion profiles. For SNU-475 cells, a model for aggressive liver cancer, many cytoskeletal inhibitors abrogated 2D migration but only some suppressed 3D migration. For HepG2 cells, cytoskeletal inhibition did not significantly affect 3D migration but did affect proliferative capabilities and spheroid core growth. This study highlights cytoskeleton driven phenotypic variation, their consequences and coexistence within the same tumor, as well as efficacy of targeting biophysical phenotypes that may be masked in traditional screens against tumor growth.
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- 2021
16. Evolutionary and Functional Analysis of Coagulase Positivity among the Staphylococci
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J. Ross Fitzgerald, Amy C. Pickering, Joana Alves, Gavin K. Paterson, Alison C MacFadyen, Robyn A Cartwright, Xiangyu Gong, Mariya I. Goncheva, Gonzalo Yebra, Bryan A. Wee, and Lukas F Muehlbauer
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Coagulase ,Staphylococcus pseudintermedius ,Swine ,Virulence Factors ,Staphylococcus ,medicine.disease_cause ,phylogeny ,Microbiology ,Birds ,Evolution, Molecular ,03 medical and health sciences ,Bacterial Proteins ,Phylogenetics ,coagulase-positive staphylococci ,evolution ,medicine ,diagnostics ,Animals ,Humans ,host specificity ,Horses ,coagulation ,Molecular Biology ,Gene ,Blood Coagulation ,Staphylococcus condimenti ,030304 developmental biology ,Genetics ,0303 health sciences ,Mutation ,biology ,030306 microbiology ,Genomics ,Staphylococcal Infections ,biology.organism_classification ,Editor's Pick ,QR1-502 ,Staphylococcus aureus ,Rabbits ,Genome, Bacterial ,von Willebrand binding protein ,Research Article - Abstract
The bacterial genus Staphylococcus comprises a large group of pathogenic and nonpathogenic species associated with an array of host species. Staphylococci are differentiated into coagulase-positive or coagulase-negative groups based on the capacity to promote clotting of plasma, a phenotype historically associated with the ability to cause disease. However, the genetic basis of this important diagnostic and pathogenic trait across the genus has not been examined to date. Here, we selected 54 representative staphylococcal species and subspecies to examine coagulation of plasma derived from six representative host species. In total, 13 staphylococcal species mediated coagulation of plasma from at least one host species including one previously identified as coagulase negative (Staphylococcus condimenti). Comparative genomic analysis revealed that coagulase activity correlated with the presence of a gene (vwb) encoding the von Willebrand binding protein (vWbp) whereas only the Staphylococcus aureus complex contained a gene encoding staphylocoagulase (Coa), the classical mediator of coagulation. Importantly, S. aureus retained vwb-dependent coagulase activity in an S. aureus strain deleted for coa whereas deletion of vwb in Staphylococcus pseudintermedius resulted in loss of coagulase activity. Whole-genome-based phylogenetic reconstruction of the Staphylococcus genus revealed that the vwb gene has been acquired on at least four different occasions during the evolution of the Staphylococcus genus followed by allelic diversification via mutation and recombination. Allelic variants of vWbp from selected coagulase-positive staphylococci mediated coagulation in a host-dependent manner indicative of host-adaptive evolution. Taken together, we have determined the genetic and evolutionary basis of staphylococcal coagulation, revealing vWbp to be its archetypal determinant. IMPORTANCE The ability of some species of staphylococci to promote coagulation of plasma is a key pathogenic and diagnostic trait. Here, we provide a comprehensive analysis of the coagulase positivity of the staphylococci and its evolutionary genetic basis. We demonstrate that the von Willebrand binding protein rather than staphylocoagulase is the archetypal coagulation factor of the staphylococci and that the vwb gene has been acquired several times independently during the evolution of the staphylococci. Subsequently, vwb has undergone adaptive diversification to facilitate host-specific functionality. Our findings provide important insights into the evolution of pathogenicity among the staphylococci and the genetic basis for a defining diagnostic phenotype.
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- 2021
17. A model involving meteorological factors for short-to-medium term water level prediction of small- and medium-sized urban rivers
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Yongjin Lei, Wanglai Ju, Xiangyu Gong, and Yawei Qin
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Hydrology ,Extreme weather ,Hydrogeology ,Flood myth ,Natural hazard ,Environmental science ,Particle swarm optimization ,Snow ,Surface runoff ,Water level - Abstract
With the increasing of extreme weathers, cities, especially the small- and medium-sized urban rivers with the protection areas less than 200 square hectares, are experiencing significantly more flood disasters worldwide. Heavy snowfalls and rainfalls can rapidly overflow these rivers and cause floods due to the their unique geographic locations and fast runoff and confluence. Therefore, it is particularly important to accurately predict the short-to-medium term water levels of such rivers for reducing and avoiding urban floods. In the present work, a particle swarm optimization (PSO)-support vector machine (SVM) water level predication model was constructed by combining PSO and SVM and trained with the meteorological data of Wuhan, China, and the water level data of Yangtze River. The PSO-SVM model is able to lower mean square error (MSE) 70.47% and increase coefficient of determination (R2) 7.02% of the prediction results, as compared with SVM model alone. The highly accurate PSO-SVM model can be used to predict river water level real-time using the hourly weather and water level data, which thereby provides quantitative data support for urban flood control, construction management of water projects, improving response efficiency and reducing safety risks.
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- 2021
18. Ca
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Mingjun, Gao, Yang, He, Xin, Yin, Xiangbin, Zhong, Bingxiao, Yan, Yue, Wu, Jin, Chen, Xiaoyuan, Li, Keran, Zhai, Yifeng, Huang, Xiangyu, Gong, Huizhong, Chang, Shenghan, Xie, Jiyun, Liu, Jiaxing, Yue, Jianlong, Xu, Guiquan, Zhang, Yiwen, Deng, Ertao, Wang, Didier, Tharreau, Guo-Liang, Wang, Weibing, Yang, and Zuhua, He
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Protein Stability ,Reproduction ,Ubiquitin-Protein Ligases ,Cell Membrane ,Ubiquitination ,Oryza ,Free Radical Scavengers ,Models, Biological ,Zea mays ,Fungal Proteins ,Species Specificity ,Calcium ,Plant Immunity ,CRISPR-Cas Systems ,Reactive Oxygen Species ,Disease Resistance ,Plant Diseases ,Plant Proteins ,Protein Binding - Abstract
Plant immunity is activated upon pathogen perception and often affects growth and yield when it is constitutively active. How plants fine-tune immune homeostasis in their natural habitats remains elusive. Here, we discover a conserved immune suppression network in cereals that orchestrates immune homeostasis, centering on a Ca
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- 2021
19. An Organotypic Mammary Duct Model Capturing Matrix Mechanics-Dependent Ductal Carcinoma
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Jonathan, Kulwatno, Xiangyu, Gong, Rebecca, DeVaux, Jason I, Herschkowitz, and Kristen L, Mills
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Carcinoma, Intraductal, Noninfiltrating ,Cell Line, Tumor ,Carcinoma, Ductal, Breast ,Tumor Microenvironment ,Humans ,Breast Neoplasms ,Female - Abstract
Ductal carcinoma
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- 2021
20. Fat reducing effects of Nelumbo nucifera leaf extract in overweight patients
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Tomonobu Konno, Enuo Liu, Hua Yan, Luyi Ye, Xiaolin Wang, Xiangyu Gong, Hao Ding, and Zai-Si Ji
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Waist ,biology ,Traditional medicine ,business.industry ,Organic Chemistry ,Nelumbo nucifera ,Plant Science ,Overweight ,Nelumbonaceae ,biology.organism_classification ,Biochemistry ,Analytical Chemistry ,Nelumbo nucifera leaf extract ,medicine ,Ingestion ,medicine.symptom ,business ,Whole body ,Body mass index - Abstract
The leaf of Nelumbo nucifera (Family Nelumbonaceae) has been widely included in the diet of Chinese people from the time of the Min Dynasty. In this study, a randomized double-blind trial (n = 60) was performed to determine the effects of extract from sun dried Nelumbo nucifera leaves (NnEx), which included quercetin-3-glucuronide (Q3GA) as the main components, in overweight patients (24 kg/m2
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- 2021
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21. Research and Evaluation of RoCE in IHEP Data Center
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Lei Han, Fazhi Qi, Shan Zeng, Tao Wu, and Xiangyu Gong
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Hardware_MEMORYSTRUCTURES ,Aeronautics ,business.industry ,Computer science ,Physics ,QC1-999 ,Data center ,business - Abstract
With more and more large-scale scientific facilities are built, more and more HPC requirements are needed in IHEP. RDMA is a technology that allows servers in a network to exchange data in main memory without involving the processor, cache or operating system of either server, which can provide high bandwidth and low latency. There are two RDMA technologies which were InfiniBand and a relative newcomer called RoCE – RDMA over Converged Ethernet. This paper introduces the RoCE technology, we research and compare the performance of both IB and RoCE in IHEP data center, and we also evaluate the application scenarios of RoCE which can support our future technology selection in HEPS. In the end, we present our future plan.
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- 2021
22. Genome sequencing of the bacterial blight pathogen DY89031 reveals its diverse virulence and origins of Xanthomonas oryzae pv. oryzae strains
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Bingxiao Yan, Zuhua He, Xiangyu Gong, Helin Li, and Fudan Chen
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0301 basic medicine ,Crops, Agricultural ,Xanthomonas ,Virulence ,Plant disease resistance ,Real-Time Polymerase Chain Reaction ,Genome ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,0302 clinical medicine ,Xanthomonas oryzae ,Xanthomonas oryzae pv. oryzae ,Gene ,Phylogeny ,General Environmental Science ,Plant Diseases ,Genetics ,biology ,Whole Genome Sequencing ,Effector ,food and beverages ,Oryza ,biology.organism_classification ,030104 developmental biology ,030220 oncology & carcinogenesis ,General Agricultural and Biological Sciences ,Genome, Bacterial - Abstract
The bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo), belonging to Xanthomonas sp., causes one of the most destructive vascular diseases in rice worldwide, particularly in Asia and Africa. To better understand Xoo pathogenesis, we performed genome sequencing of the Korea race 1 strain DY89031 (J18) and analyzed the phylogenetic tree of 63 Xoo strains. We found that the rich diversity of evolutionary features is likely associated with the rice cultivation regions. Further, virulence effector proteins secreted by the type III secretion system (T3SS) of Xoo showed pathogenesis divergence. The genome of DY89031 shows a remarkable difference from that of the widely prevailed Philippines race 6 strain PXO99A, which is avirulent to rice Xa21, a well-known disease resistance (R) gene that can be broken down by DY89031. Interestingly, plant inoculation experiments with the PXO99A transformants expressing the DY89031 genes enabled us to identify additional TAL (transcription activator-like) and non-TAL effectors that may support DY89031-specific virulence. Characterization of DY89031 genome and identification of new effectors will facilitate the investigation of the rice-Xoo interaction and new mechanisms involved.
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- 2020
23. NLRs guard metabolism to coordinate pattern- and effector-triggered immunity
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Keran Zhai, Di Liang, Helin Li, Fangyuan Jiao, Bingxiao Yan, Jing Liu, Ziyao Lei, Li Huang, Xiangyu Gong, Xin Wang, Jiashun Miao, Yichuan Wang, Ji-Yun Liu, Lin Zhang, Ertao Wang, Yiwen Deng, Chi-Kuang Wen, Hongwei Guo, Bin Han, and Zuhua He
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Multidisciplinary ,Methionine ,Oryza ,Plant Immunity ,Plants ,Plant Diseases ,Signal Transduction - Abstract
Pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) in plants enable them to respond to pathogens by activating the production of defence metabolites that orchestrate immune responses
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- 2020
24. An Organotypic Mammary Duct Model Capturing Distinct Events of DCIS Progression
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Xiangyu Gong, Jason I. Herschkowitz, Jonathan Kulwatno, Rebecca Sinnott DeVaux, and Kristen L. Mills
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Basement membrane ,Tumor microenvironment ,Ductal carcinoma ,Hyperplasia ,Biology ,medicine.disease ,Breast cancer ,medicine.anatomical_structure ,Stroma ,medicine ,Cancer research ,Overdiagnosis ,skin and connective tissue diseases ,Duct (anatomy) - Abstract
Ductal carcinoma in situ (DCIS) is a pre-cancerous stage breast cancer, where abnormal cells are contained within the duct, but have not invaded into the surrounding tissue. However, only 30-40% of DCIS cases are likely to progress into an invasive ductal carcinoma (IDC), while the remainder are innocuous. Since little is known about what contributes to the transition from DCIS to IDC, clinicians and patients tend to opt for treatment, leading to concerns of overdiagnosis and overtreatment. In vitro models are currently being used to probe how DCIS transitions into IDC, but many models do not take into consideration the macroscopic tissue architecture and the biomechanical properties of the microenvironment. Here, we developed an organotypic mammary duct model by molding a channel within a collagen matrix and lining it with a basement membrane. By adjusting the concentration of collagen, we effectively modulated the stiffness and morphological properties of the matrix and examined how an assortment of breast cells responded to changing density and stiffness of the matrix. We first validated the model using two established, phenotypically divergent breast cancer cell lines by demonstrating the ability of the cells to either invade (MDA-MB-231) or cluster (MCF7). We then examined how cells of the isogenic MCF10 series—spanning the range from healthy to aggressive—behaved within our model and observed distinct characteristics of breast cancer progression such as hyperplasia and invasion, in response to collagen concentration. Our results show that the model can recapitulate different stages of breast cancer progression and that the MCF10 series is adaptable to physiologically relevant in vitro studies, demonstrating the potential of both the model and cell lines to elucidate key factors that may contribute to understanding the transition from DCIS to IDC.IMPACT STATEMENTThe success of early preventative measures for breast cancer has left patients susceptible to overdiagnosis and overtreatment. Limited knowledge of factors driving an invasive transition has inspired the development of in vitro models that accurately capture this phenomenon. However, current models tend to neglect the macroscopic architecture and biomechanical properties of the mammary duct. Here, we introduce an organotypic model that recapitulates the cylindrical geometry of the tissue and the altered stroma seen in tumor microenvironments. Our model was able to capture distinct features associated with breast cancer progression, demonstrating its potential to uncover novel insights into disease progression.
- Published
- 2020
25. Rapid fabrication of collagen bundles mimicking tumor-associated collagen signatures
- Author
-
Kristen L. Mills, Xiangyu Gong, and Jonathan Kulwatno
- Subjects
0303 health sciences ,Stromal cell ,Chemistry ,02 engineering and technology ,021001 nanoscience & nanotechnology ,medicine.disease ,In vitro ,Metastasis ,03 medical and health sciences ,Tumor progression ,In vivo ,Nanofiber ,Cancer cell ,Reticular connective tissue ,medicine ,Biophysics ,0210 nano-technology ,030304 developmental biology - Abstract
Stromal collagen surrounding a solid tumor tends to present as dense, thick bundles. The collagen bundles are remodeled during tumor progression: first tangential to the tumor boundary (indicating growth) and later perpendicular to the tumor boundary (indicating likely metastasis). Current reconstituted-collagenin vitrotumor models are unable to recapitulate thein vivostructural features of collagen bundling and alignment. Here, we present a rapid yet simple procedure to fabricate collagen bundles with an average thickness of 9 μm, compared to the reticular dense collagen nanofiber (∼900 nm-diameter, on average) prepared using common protocols. The versatility of the collagen bundles was demonstrated with their incorporation into twoin vitromodels where the thickness and alignment of the collagen bundles resembled the variousin vivoarrangements. First, collagen bundles aligned by a microfluidic device elicited cancer cell contact guidance and enhanced their directional migration. Second, the presence of the collagen bundles in a bio-inert agarose hydrogel was shown to provide a highway for cancer cell invasion. The unique structural features of the collagen bundles advance the physiological relevance ofin vitrocollagen-based tumor models for accurately capturing cancer cell-stroma interactions.
- Published
- 2019
26. Evolutionary and Functional Analysis of Coagulase Positivity among the Staphylococci.
- Author
-
Pickering, Amy C., Yebra, Gonzalo, Xiangyu Gong, Goncheva, Mariya I., Wee, Bryan A., MacFadyen, Alison C., Muehlbauer, Lukas F., Alves, Joana, Cartwright, Robyn A., Paterson, Gavin K., and Fitzgerald, J. Ross
- Published
- 2021
- Full Text
- View/download PDF
27. Rotary Actuators Based on Pneumatically Driven Elastomeric Structures
- Author
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Parth Kulkarni, Ke Yang, Xiangyu Gong, Aaron D. Mazzeo, Yanjun Wang, Jingjin Xie, and Alexander S. Hobbs
- Subjects
0209 industrial biotechnology ,Materials science ,business.industry ,Mechanical Engineering ,Soft robotics ,Mechanical engineering ,Robotics ,02 engineering and technology ,Bending ,Rotary actuator ,021001 nanoscience & nanotechnology ,020901 industrial engineering & automation ,Pneumatics ,Mechanics of Materials ,Torque ,Robot ,General Materials Science ,Artificial intelligence ,0210 nano-technology ,Actuator ,business - Abstract
Unique elastomeric rotary actuators based on pneumatically driven peristaltic motion are demonstrated. Using silicone-based wheels, these motors enable a new class of soft locomotion not found in nature, which is capable of withstanding impact, traversing irregular terrain, and operating in water. For soft robotics, this work marks progress toward providing torque without bending actuators.
- Published
- 2016
28. Large-scale patterning of single cells and cell clusters in hydrogels
- Author
-
Kristen L. Mills and Xiangyu Gong
- Subjects
0301 basic medicine ,Cell division ,Cell ,Population ,Cell Culture Techniques ,lcsh:Medicine ,Cell Communication ,Article ,Biophysical Phenomena ,Extracellular matrix ,03 medical and health sciences ,Laminin ,Cell Line, Tumor ,Tumor Microenvironment ,medicine ,Humans ,lcsh:Science ,education ,education.field_of_study ,Matrigel ,Multidisciplinary ,biology ,Chemistry ,lcsh:R ,Hydrogels ,HCT116 Cells ,Extracellular Matrix ,Drug Combinations ,030104 developmental biology ,medicine.anatomical_structure ,Cell culture ,Self-healing hydrogels ,biology.protein ,Proteoglycans ,lcsh:Q ,Collagen ,Biological system - Abstract
Biophysical properties of the extracellular matrix (ECM) are known to play a significant role in cell behavior. To gain a better understanding of the effects of the biophysical microenvironment on cell behavior, the practical challenge is longitudinally monitoring behavioral variations within a population to make statistically powerful assessments. Population-level measurements mask heterogeneity in cell responses, and large-scale individual cell measurements are often performed in a one-time, snapshot manner after removing cells from their matrix. Here we present an easy and low-cost method for large-scale, longitudinal studies of heterogeneous cell behavior in 3D hydrogel matrices. Using a platform we term “the drop-patterning chip”, thousands of cells were simultaneously transferred from microwell arrays and fully embedded, only using the force of gravity, in precise patterns in 3D collagen I or Matrigel. This method allows for throughputs approaching 2D patterning methods that lack phenotypic information on cell-matrix interactions, and does not rely on special equipment and cell treatments that may result in a proximal stiff surface. With a large and yet well-organized group of cells captured in 3D matrices, we demonstrated the capability of locating selected individual cells and monitoring cell division, migration, and proliferation for multiple days.
- Published
- 2018
29. Research on Precise Tracking Control of Gear-Shifting Actuator for Non-Synchronizer Automatic Mechanical Transmission Based on Sleeve Trajectory Planning
- Author
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Xiangyu Gongye, Changqing Du, Longjian Li, Cheng Huang, Jinhai Wang, and Zhengli Dai
- Subjects
Non-Synchronizer Automated Mechanical Transmission ,active angle alignment ,shift actuator control ,algorithm design ,Technology - Abstract
The Non-Synchronizer Automated Mechanical Transmission (NSAMT) demonstrates a straightforward structure and cost-effectiveness; however, the primary obstacle to its widespread application lies in NSAMT shift control. The implementation of active angle alignment effectively addresses the issue of shifting quality, but achieving active angle alignment necessitates precise tracking of the planned shifting curve by the gear-shifting actuator. To tackle the control problem of accurate tracking for NSAMT shift actuators, this paper initially analyzes the structure and shift characteristics of the NSAMT. Based on this analysis, a physical model is established using Amesim, incorporating a drive motor, two-gear NSAMT, shift actuator, sleeve, and DC motor model. An extended state observer (ESO) is designed to mitigate unknown interference within the system. Furthermore, an active angle alignment control algorithm based on “zero speed difference” and “zero angle difference” for double target tracking is constructed while planning the axial motion trajectory of the sleeve. The Backstepping algorithm is employed to successfully track and regulate this planned trajectory. Finally, through Hardware-in-the-Loop testing, we validate our proposed control strategy, which demonstrates consistent results with simulation outcomes, thereby affirming its effectiveness.
- Published
- 2024
- Full Text
- View/download PDF
30. Three-dimensional single cell patterning for mid- to high-throughput studies of tumor cell and extracellular matrix heterogeneity
- Author
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Kristen L. Mills and Xiangyu Gong
- Subjects
Extracellular matrix ,Tumor microenvironment ,Stromal cell ,Genetic heterogeneity ,Tumor progression ,Cancer cell ,Computational biology ,Biology ,Bioinformatics ,Cell patterning ,Throughput (business) - Abstract
Cancer heterogeneity includes cancer cell genetic heterogeneity and heterogeneity in the tumor microenvironment (TME)—both stromal cells and extracellular matrix (ECM). Determining which combinations of the vast array of possibly interacting heterogeneities drive tumor progression presents a major multi-disciplinary challenge in cancer research. To make effective treatment decisions this challenge must be addressed. The practical challenge is assessing cellular heterogeneity in a statistically powerful way with respect to targeted TME characteristics. Here we present a simple, but extensible, and low-cost method for conducting mid- to high-throughput and long-term studies of heterogeneous cell responses to various biomechanical stimuli in 3D models mimicking the biomechanical properties of the ECM. Using a platform we term “the drop-patterning chip” thousands of cells are simultaneously transferred from microwells and fully embedded, only using the force of gravity, in precise patterns in 3D. This method allows for throughputs approaching flow-through methods, which lack phenotypic information on cell-matrix interactions, and does not rely on expensive or harsh patterning forces, which often times also result in a proximal stiff surface.
- Published
- 2017
- Full Text
- View/download PDF
31. Alcaligenes faecalis penicillin G acylase-catalyzed enantioselective acylation of dl-phenylalanine and derivatives in aqueous medium
- Author
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Erzheng Su, Dongzhi Wei, Pixiang Wang, and Xiangyu Gong
- Subjects
Alcaligenes faecalis ,biology ,Aqueous medium ,Stereochemistry ,Chemistry ,Organic Chemistry ,Enantioselective synthesis ,biology.organism_classification ,Biochemistry ,Catalysis ,Reaction rate ,Acylation ,Penicillin G Acylase ,Enantiopure drug ,Drug Discovery ,Organic chemistry ,lipids (amino acids, peptides, and proteins) - Abstract
A new strategy based on enantioselective acylation properties of relatively unknown penicillin G acylase from Alcaligenes faecalis has been developed for the production of pharmacologically interesting enantiomerically pure d -phenylalanine. In order to get high reaction rate and enantioselectivity, two key factors (pH and temperature) and eight different acyl donors were optimized, and the optimal acylation reaction was carried out at pH 10, 35 °C, using phenylacetamide as the acyl donor. This enantioselective acylating method is also illustrated by the effective production of five different p-substituted phenylalanine derivatives in enantiopure.
- Published
- 2011
32. A facile pretreatment method for efficient immobilization of penicillin G acylase
- Author
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Erzheng Su, Dongzhi Wei, Xiangyu Gong, Jingli Xie, and Pixiang Wang
- Subjects
Environmental Engineering ,Chromatography ,Immobilized enzyme ,Chemistry ,Sonication ,Extraction (chemistry) ,Biomedical Engineering ,Bioengineering ,Penicillin amidase ,Pretreatment method ,chemistry.chemical_compound ,Adsorption ,Specific activity ,Butyl acetate ,Biotechnology - Abstract
A facile pretreatment method was developed to obtain high specific activity of PGA from recombinant E. coli cells for preparing immobilized enzyme with high activity, which coupled selective extraction of PGA with butyl acetate and adsorption of butyl acetate with active carbon. Butyl acetate (5%, v/v) led to a 92.0% release of PGA, the specific activity of which in the extracting solution was twice that obtained by sonication. The negative effect on PGA immobilization due to residual butyl acetate in the extracting solution was removed by adding active carbon (8%, w/v). The final PGA solution meets requirement for industrial immobilization while eliminating the high cost of a traditional purification process. This pretreatment method developed in this work is simple, highly performing and cost-effective. It has been employed in a 10 tons/year immobilized PGA production line.
- Published
- 2011
33. A high capacity steganographic method based on quantization table modification
- Author
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Cuiling Jiang, Lun Guo, Bing Jing, Xiangyu Gong, and Yilin Pang
- Subjects
Multidisciplinary ,Pixel ,Steganography ,Information hiding ,Discrete cosine transform ,computer.file_format ,Arithmetic ,Quantization (image processing) ,JPEG ,computer ,Algorithm ,Mathematics - Abstract
For the traditional steganographic method of Jsteg, the emmbedment of secret message is completed by dividing cover-image into nonoverlapping blocks of 8×8 pixels, discrete cosine transform (DCT) transforming, and using the standard 8×8 quantization table to quantize. In this paper, a novel steganographic method based on the JPEG quantization table modification is presented. Instead of dividing cover-image into 8×8 blocks, nonoverlapping blocks of 16×16 pixels is used. Both theoretical anlysis and experiment results show that the new methods has larger steganography capacity and better stego-image quality, compared with the method of Jsteg and Chang’s.
- Published
- 2011
34. Lipase‐Catalyzed Irreversible Transesterification of Jatropha Curcas L. Seed Oil to Fatty Acid Esters: An Optimization Study
- Author
-
Xiangyu Gong, Liqin Du, Erzheng Su, and Pixiang Wang
- Subjects
chemistry.chemical_classification ,Central composite design ,biology ,General Chemical Engineering ,Organic Chemistry ,Diethyl carbonate ,Fatty acid ,Transesterification ,biology.organism_classification ,chemistry.chemical_compound ,chemistry ,Yield (chemistry) ,parasitic diseases ,biology.protein ,Organic chemistry ,Response surface methodology ,Lipase ,Jatropha curcas - Abstract
In this work, fatty acid ethyl esters were produced from the lipase-catalyzed irreversible transesterification reaction between Jatropha oil and diethyl carbonate (DEC). Response surface methodology (RSM) based on central composite design (CCD) was used to optimize the five important reaction variables for the irreversible transesterification of Jatropha oil in a solvent-free system. The optimum conditions for the transesterification were a reaction time of 13.3 h, a temperature of 44.5 °C, a lipase amount of 13.7% (w/w), a DEC to Jatropha oil molar ratio of 3.75:1 and no need for adding water. The optimal predicted yield of fatty acid esters was 97.7% and the actual value was 96.2%. The results showed that the RSM based on CCD was adaptable for a fatty acid esters yield study for the current transesterification system.
- Published
- 2010
35. Purification and in situ immobilization of papain with aqueous two-phase system
- Author
-
Pengyong You, Xiangyu Gong, Ming Sun, Diansheng Xu, Erzheng Su, Mingliang Li, and Dongzhi Wei
- Subjects
Latex ,Hydrolases ,lcsh:Medicine ,Plant Science ,Biochemistry ,Polyethylene Glycols ,Chitosan ,chemistry.chemical_compound ,Engineering ,Papain ,Biological Systems Engineering ,lcsh:Science ,Chromatography, High Pressure Liquid ,Chromatography ,Multidisciplinary ,Aqueous solution ,Carica ,Enzyme Classes ,Physics ,Statistics ,Temperature ,Chemical Reactions ,Hydrogen-Ion Concentration ,Enzymes ,Chemistry ,Cross-Linking Reagents ,Electrophoresis, Polyacrylamide Gel ,Research Article ,Biotechnology ,Immobilized enzyme ,Central composite design ,Materials Science ,Biophysics ,Bioengineering ,Protein Chemistry ,Catalysis ,Natural Materials ,Hydrolysis ,PEG ratio ,Biology ,lcsh:R ,Aqueous two-phase system ,Water ,Enzymes, Immobilized ,chemistry ,Statistical Theories ,Biocatalysis ,lcsh:Q ,Plant Biotechnology ,Mathematics - Abstract
Papain was purified from spray-dried Carica papaya latex using aqueous two-phase system (ATPS). Then it was recovered from PEG phase by in situ immobilization or preparing cross-linked enzyme aggregates (CLEAs). The Plackett-Burman design and the central composite design (CCD) together with the response surface methodology (RSM) were used to optimize the APTS processes. The highly purified papain (96–100%) was achieved under the optimized conditions: 40% (w/w) 15 mg/ml enzyme solution, 14.33–17.65% (w/w) PEG 6000, 14.27–14.42% (w/w) NaH2PO4/K2HPO4 and pH 5.77–6.30 at 20°C. An in situ enzyme immobilization approach, carried out by directly dispersing aminated supports and chitosan beads into the PEG phase, was investigated to recover papain, in which a high immobilization yield (>90%) and activity recovery (>40%) was obtained. Moreover, CLEAs were successfully used in recovering papain from PEG phase with a hydrolytic activity hundreds times higher than the carrier-bound immobilized papain.
- Published
- 2010
36. A novel esterase Sso2518 from Sulfolobus solfataricus with a much lower temperature optimum than the growth temperature
- Author
-
Jiayi Wang, Jianjun Wang, Xiangyu Gong, and Guojun Zheng
- Subjects
chemistry.chemical_classification ,biology ,ved/biology ,Sulfolobus solfataricus ,ved/biology.organism_classification_rank.species ,Esterases ,Temperature ,Bioengineering ,Sulfolobaceae ,General Medicine ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Esterase ,Substrate Specificity ,Hydrolysis ,Enzyme ,Biochemistry ,chemistry ,Catalytic triad ,Escherichia coli ,Cloning, Molecular ,Sulfolobales ,Bacteria ,Biotechnology - Abstract
An esterase, Sso2518, from Sulfolobus solfataricus P2 was over-expressed in E. coli. and characterized after purification. The maximum activity was at pH 7.5 and 50 degrees C. The half life of Sso2518 was about 30 min at 85 degrees C and the enzyme was activated by Cu(2+). The catalytic triad of Sso2518 was comprised of residues Ser151, Asp176, and His328. Sso2518 showed the highest activity with p-nitrophenyl caproate (C6) and could also hydrolyze olive oil. Under native conditions, Sso2518 consists of 125 kDa homotrimers.
- Published
- 2010
37. All-solid-state continuous-wave frequency-doubling Nd:YVO(4)/LBO laser with 2.35 W output power at 543 nm
- Author
-
Zhou Kai, Y. Yao, Xiangyu Gong, Yang Liu, Quan Zheng, Zhao Ling, and Dapeng Qu
- Subjects
Materials science ,business.industry ,Energy conversion efficiency ,Second-harmonic generation ,Nonlinear optics ,Laser ,Atomic and Molecular Physics, and Optics ,law.invention ,chemistry.chemical_compound ,Optics ,chemistry ,law ,Attenuation coefficient ,Lithium triborate ,Optoelectronics ,Continuous wave ,business ,Diode - Abstract
An efficient and compact red laser at 458 nm is generated by intracavity frequency doubling of a continuous wave (CW) laser operation of a diode pumped Nd:LuVO4 laser at 916 nm under the condition of suppression the higher gain transition near 1064 nm. With 30 W diode pump power and a frequency doubling crystal LBO, as high as 9.6 W of CW output power at 458 nm is achieved, corresponding to an optical-to-optical conversion efficiency of 32.0% and the output power stability in 8 hours is better than 2.35%. To the best of our knowledge, this it the highest conversion efficiency of watt-level laser at 458 nm generated by intracavity frequency doubling of a diode pumped Nd:LuVO4 laser at 916 nm.
- Published
- 2009
38. Active Mode Switching Control Strategy of Hybrid Electric Vehicle based on Identification of Road Gradient
- Author
-
Ming Ye, Xiangyu Gongye, Zhihong Zhu, and Wenlei Wei
- Subjects
Identification of road gradient ,Model prediction ,Dynamic planning ,Active mode switching ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
In order to study the control strategy of active mode switching for single shaft parallel hybrid electric vehicles based on identification of road gradient, the numerical model of hybrid electric vehicle and road gradient model are built on the Matlab. On the basis of road gradient identification,the speed and demand torque of hybrid electric power system at the next time are predicted by the simulation model. The working mode of hybrid electric vehicle is determined according to the required torque and the SOC of the battery at the current time and the next time. On the basis of determining the working mode first,taking the minimum fuel consumption as the objective function,the optimal torque allocation is carried out in real time with dynamic programming algorithm. On the premise of economy,the hybrid power system can achieve the shift gear at the uphill moment to meet the needs of driver's power performance and drivability.
- Published
- 2019
- Full Text
- View/download PDF
39. Research on Dynamic Coordination Active Mode Switching Control Strategy for Hybrid Electric Vehicle Based on Traffic Information
- Author
-
Ming Ye, Xiangyu Gongye, Yonggang Liu, and Xiao Wang
- Subjects
Active mode switching ,HIL ,hybrid vehicle ,intelligent network ,optimal traffic light control ,traffic scene ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
In traditional hybrid-vehicle mode switching, a switch when it changes in road conditions is sensed. Because of the delays in the control system, lags in switching and large impacts on the switching process occur, in what is referred to as “passive mode switching.” Via a combination of an intelligent networked hybrid vehicle with environmental sensing, “passive mode switching” can be converted into “active mode switching,” reducing the impact degree during the switching process and increasing ride comfort. Combined with the application of intelligent transportation system in current traffic, an intelligent traffic scene with optimal traffic-light control (OTLC) is established. The OTLC algorithm determines the future driving-state information of the hybrid vehicle in a built scenario and predicts the driving mode of the hybrid vehicle for the next moment. The current mode and future mode are compared, active control of key components, such as the engine, motor, clutch, and electric-mechanical continuously variable transmission (EMCVT), under the premise of different conditions, is made possible, and corresponding dynamic coordinate active-mode-switching control strategies are developed. The proposed control strategy is simulated and verified on a built-in hardware-in-the-loop (HIL) test platform based on traffic scenarios. The results show that the dynamic coordinated active-mode-switching control strategy presented in this paper is superior to the traditional mode-switching control strategy and that it can overcome the problem of switching lag due to delays in the control system and the large impact during the switching process, reducing the impact degree by about 21.2%, which improves ride comfort.
- Published
- 2019
- Full Text
- View/download PDF
40. Erratum to: A novel esterase Sso2518 from Sulfolobus solfataricus with a much lower temperature optimum than the growth temperature
- Author
-
Jianjun Wang, Jiayi Wang, Xiangyu Gong, and Guojun Zheng
- Subjects
Bioengineering ,General Medicine ,Applied Microbiology and Biotechnology ,Biotechnology - Published
- 2010
41. A novel esterase Sso2518 from Sulfolobus solfataricus with a much lower temperature optimum than the growth temperature.
- Author
-
Jianjun Wang, Jiayi Wang, Xiangyu Gong, and Guojun Zheng
- Subjects
ESTERASES ,ESCHERICHIA coli ,ENZYMES ,HYDROLASES ,ESCHERICHIA - Abstract
An esterase, Sso2518, from Sulfolobus solfataricus P2 was over-expressed in E. coli. and characterized after purification. The maximum activity was at pH 7.5 and 50°C. The half life of Sso2518 was about 30 min at 85°C and the enzyme was activated by Cu
2+ . The catalytic triad of Sso2518 was comprised of residues Ser151, Asp176, and His328. Sso2518 showed the highest activity with p-nitrophenyl caproate (C6) and could also hydrolyze olive oil. Under native conditions, Sso2518 consists of 125 kDa homotrimers. [ABSTRACT FROM AUTHOR]- Published
- 2010
- Full Text
- View/download PDF
42. Review on the Development, Control Method and Application Prospect of Brake-by-Wire Actuator
- Author
-
Xiaoxiang Gong, Weiguo Ge, Juan Yan, Yiwei Zhang, and Xiangyu Gongye
- Subjects
brake-by-wire ,braking force control ,wheel anti-lock control ,regenerative brake strategy ,braking force distribution strategy ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Production of electric energy or power. Powerplants. Central stations ,TK1001-1841 - Abstract
This paper reviews and summarizes the development, key technologies, and application of brake-by-wire (BBW) actuators. BBW is the technology orientation of future vehicle brake system. The main feature of BBW is to replace some of the mechanical and hydraulic components of traditional brake system with electronic control components, and use cables and wires to transmit energy and signals. BBW actuators have outstanding advantages, such as fast response, accurate control, and compact structure. They are easy to integrate with active safety functions and they are easily matched with the regenerative braking systems of electric vehicle. First, this paper summarizes the classification, characteristics, performance, and architecture of BBW actuators. Subsequently, the braking process regulation of vehicle is considered to be the main target, which is summarized from two aspects of actuator regulation and braking force distribution. The state estimation algorithm and control algorithm applied to these actuators are summarized and analyzed, and the development trend, challenges, and schemes of the braking force distribution are proposed. The development and research trend of braking force match strategies between the regenerative brake system and BBW system are also analyzed and summarized. The further electrification and intelligence of vehicle demand BBW’s braking force control method and distribution method must have higher control accuracy, stronger robustness, and wider adaptability, and the effects on braking comfort and handling stability must be further discussed.
- Published
- 2020
- Full Text
- View/download PDF
43. Material Model of Membrane Structure in Rainstorm
- Author
-
PANG Yan, QING Qiang, WANG Shasha, ZHANG Xiangyu, GONG Jinghai
- Subjects
membrane structure ,water accumulation ,membrane material model ,numerical simulation ,deformation prediction ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Chemical engineering ,TP155-156 ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 - Abstract
When encountering heavy rain, the membrane surface with a relatively small slope is easy to accumulate water. Accurately simulating the deformation of the membrane surface at this time will help ensure the safety of the structure. The linear constitutive model of membrane material used in existing research is not suitable for simulating the deformation of membrane structure in rainstorm. This study conducts a uniform load test on a membrane structure to simulate the mechanical behavior of the membrane surface in rainstorm and obtains the deformation form of the structure when water is accumulated. The linear constitutive model and the double broken line constitutive model of membrane material are used in the finite element model of the membrane structure for load analysis. By comparing the deformation of the finite element model and the actual structure, it selects the constitutive model suitable for simulating the deformation of the membrane structure in heavy rain. The numerical simulation results show that the structural deformation simulated by the double broken line constitutive model is closer to the deformation measured in the experiment than the linear constitutive model. The research results can provide a reference for the selection of the membrane constitutive model and the analysis of membrane structure in rainstorm.
- Published
- 2023
- Full Text
- View/download PDF
44. All-solid-state continuous-wave frequency-doubling Nd:YVO4/LBO laser with 2.35 W output power at 543 nm.
- Author
-
Yi Yao, Quan Zheng, Dapeng Qu, Xiangyu Gong, Kai Zhou, Yang Liu, and Ling Zhao
- Published
- 2009
- Full Text
- View/download PDF
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