168 results on '"Chunlei Chen"'
Search Results
52. Clinical Significance of Multiparameter Intracranial Pressure Monitoring in the Prognosis Prediction of Hypertensive Intracerebral Hemorrhage
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Yongbo Yang, Yuchun Pan, Chunlei Chen, Penglai Zhao, and Chunhua Hang
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multi-parameter intracranial pressure monitoring ,hypertensive intracerebral hemorrhage ,brain injury ,body regions ,musculoskeletal, neural, and ocular physiology ,Medicine ,General Medicine - Abstract
Objective: The present study aimed to investigate the clinical significance of multiparameter intracranial pressure (ICP) monitoring in the prediction of the prognosis of hypertensive intracerebral hemorrhage (HICH). Methods: A retrospective analysis was performed on the clinical data of 53 HICH patients. The patients underwent removal of intracranial hemorrhage and decompressive craniectomy after admission. A ventricular ICP monitoring probe was used to continuously and invasively monitor mean arterial pressure (MAP) and ICP after surgery. The NEUMATIC system was used to collect ICP data, including pressure reactivity index (PRx), ICP dose (DICP), amplitude and pressure regression (RAP), and cerebral perfusion pressure (CPP). The mean PRx, CPP, RAP, ICP, and DICP20 mmHg × h were calculated with 1 h as the time segment. According to the Glasgow outcome scale (GOS) scores after discharge, the patients were grouped into the poor prognosis group (GOS I–III) and the good prognosis group (GOS IV and V). The two groups were compared in terms of GOS scores in the treatment and prediction of prognosis of patients. Results: The good prognosis group showed significantly lower values of mean ICP, DICP20 mmHg × h, RAP, and PRx than the poor prognosis group, while CPP was significantly higher (p < 0.001). Conclusions: PRx, DICP, RAP, and CPP could reflect intracranial changes in patients and were significantly correlated with the prognosis of the patients. Mean ICP, PRx, DICP20 mmHg × h, and RAP were negatively correlated with prognosis, while CPP was positively correlated with prognosis.
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- 2022
53. Carbazole and polyhalogenated carbazoles in the marine environment around the Zhoushan Archipelago: Distribution characteristics, environmental behavior, and sources
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Zhaochao Deng, Songtao Hu, Leiming Tang, Lingbo Jiang, Junyu He, Keyu Shen, Yongjiu Xu, Rijin Jiang, Tiejun Li, Chunlei Chen, Bairu Chen, Hanghai Zhou, Dongdong Zhang, Jiawang Chen, and Chunfang Zhang
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Geologic Sediments ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Carbazoles ,Water ,Environmental Chemistry ,Pollution ,Waste Management and Disposal ,Water Pollutants, Chemical ,Ships ,Environmental Monitoring - Abstract
The distribution characteristics and drivers of carbazole (CZ) and polyhalogenated carbazoles are still poorly understood. In this study, 96 samples were collected around the Zhoushan Archipelago, and their distribution characteristics were assessed. The results showed that CZ, 36-CCZ, and 36-BCZ were the top three abundant congeners in most collected samples. The bioaccumulation analysis revealed that marine plants prefer to accumulate CZ and bromocarbazoles rather than chlorocarbazoles. Both the mean concentrations of total carbazole and its derivants (ΣCZDs), as well as individual congeners, are the highest in sediments around the berthing areas of cargo ships and oil tankers. Meanwhile, ΣCZDs of these sediments are significantly influenced by the geo-weighted displacement of ships (r = 0.61; p 0.05), indicating the ballast water from these ships as potential contributor for marine CZDs. Moreover, the accumulation of CZ in plankton, planktonic origin of sedimentary organic matter, and relationship between CZ and C/N ratio (p 0.05) in sediments support the scenario that plankton absorbs and takes CZ into the sediments. These findings will promote the understanding of the sources, environmental behaviors, and fates of marine CZDs.
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- 2023
54. Convolutional neural network for the diagnosis of early gastric cancer based on magnifying narrow band imaging
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Chunlei Chen, Chaohui Yu, Zhe Shen, Jianzhong Sang, Ming Chen, Chao-Hui Jin, Yong Ding, Xiaoyun Yang, Lan Li, Xuequn Zhang, Jun Li, and Yishu Chen
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Cancer Research ,medicine.medical_specialty ,Convolutional neural network ,Sensitivity and Specificity ,Narrow Band Imaging ,03 medical and health sciences ,0302 clinical medicine ,Primary outcome ,Stomach Neoplasms ,Image Processing, Computer-Assisted ,medicine ,Humans ,Early Detection of Cancer ,Magnifying endoscopy ,Early gastric cancer ,Narrow-band imaging ,business.industry ,Significant difference ,Mucosal lesions ,Gastroenterology ,General Medicine ,Predictive value ,Early Gastric Cancer ,Oncology ,Gastric Mucosa ,030220 oncology & carcinogenesis ,Original Article ,030211 gastroenterology & hepatology ,Neural Networks, Computer ,Radiology ,business - Abstract
Background Magnifying endoscopy with narrow band imaging (M-NBI) has been applied to examine early gastric cancer by observing microvascular architecture and microsurface structure of gastric mucosal lesions. However, the diagnostic efficacy of non-experts in differentiating early gastric cancer from non-cancerous lesions by M-NBI remained far from satisfactory. In this study, we developed a new system based on convolutional neural network (CNN) to analyze gastric mucosal lesions observed by M-NBI. Methods A total of 386 images of non-cancerous lesions and 1702 images of early gastric cancer were collected to train and establish a CNN model (Inception-v3). Then a total of 341 endoscopic images (171 non-cancerous lesions and 170 early gastric cancer) were selected to evaluate the diagnostic capabilities of CNN and endoscopists. Primary outcome measures included diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value. Results The sensitivity, specificity, and accuracy of CNN system in the diagnosis of early gastric cancer were 91.18%, 90.64%, and 90.91%, respectively. No significant difference was spotted in the specificity and accuracy of diagnosis between CNN and experts. However, the diagnostic sensitivity of CNN was significantly higher than that of the experts. Furthermore, the diagnostic sensitivity, specificity and accuracy of CNN were significantly higher than those of the non-experts. Conclusions Our CNN system showed high accuracy, sensitivity and specificity in the diagnosis of early gastric cancer. It is anticipated that more progress will be made in optimization of the CNN diagnostic system and further development of artificial intelligence in the medical field.
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- 2019
55. Rhamnolipids amendment improves soil properties and enhances microecological functions in the saline-alkali soil
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Shichen Li, Hanghai Zhou, Chunlei Chen, Feng Zeng, Gang Zheng, Xingpeng Wang, and Chunfang Zhang
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Environmental Engineering - Abstract
A laboratory-scale study was conducted to investigate the effect of rhamnolipids (RLs) supplement on the amelioration of saline-alkali soils. The RLs supplement improved the soil aggregates stability and promoted the formation of macro-aggregates which increased by up to 10.84% and 15.92% in alkaline soil and saline soil, respectively. In addition, RLs amendment led to a pH reduction from initial 8.87 to 7.80–7.84 in alkaline soil, and a salt rejection up to 20.72% in saline soil, remarkably alleviating the saline-alkali stress on microorganisms and plants. Meanwhile, microbial growth and activity as well as the seed germination performance were greatly improved in both types of soil. Furthermore, RLs addition greatly altered the microbial community structure and supported the proliferation of bacterial species (e.g., Pseudomonas oleovorans, Pseudomonas stutzeri, and Alcanivorax dieselolei) that favored the improvement of soil properties and nutrients circulation, thus markedly enhancing the microecological functions including carbon and nitrogen metabolisms. Further supplement of γ-PGA only exhibited promoting effect on aggregates formation and microbial growth and activity. The findings obtained in this study prove the application of RLs as a promising approach for saline-alkali soil amelioration.
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- 2022
56. Effect of microplastics on microbial dechlorination of a polychlorinated biphenyl mixture (Aroclor 1260)
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Xinkai Li, Qiang Xu, Youjun Cheng, Chunlei Chen, Chaofeng Shen, Chunfang Zhang, Daoqiong Zheng, and Dongdong Zhang
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Aroclors ,Geologic Sediments ,Biodegradation, Environmental ,Environmental Engineering ,Microplastics ,Environmental Chemistry ,Chloroflexi ,Chlorine ,Plastics ,Polychlorinated Biphenyls ,Pollution ,Waste Management and Disposal - Abstract
Microplastics (MPs) and polychlorinated biphenyls (PCBs) generally coexist in the environment, posing risks to public health and the environment. This study investigated the effect of different MPs on the microbial anaerobic reductive dechlorination of Aroclor 1260, a commercial PCB mixture. MP exposure inhibited microbial reductive dechlorination of PCBs, with inhibition rates of 39.43%, 23.97%, and 17.53% by polyethylene (PE), polypropylene (PP), and polystyrene (PS), respectively. The dechlorination rate decreased from 1.63 μM Cl
- Published
- 2022
57. Education of Oversea Computer-major Students in Weifang University
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Chengduan Wang, Ming Qi, Peng Zhang, Chunlei Chen, Jinkui Hou, and Shutian Lu
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Higher education ,business.industry ,05 social sciences ,050301 education ,02 engineering and technology ,Public relations ,Student education ,Internationalization ,020204 information systems ,Political science ,Scale (social sciences) ,0202 electrical engineering, electronic engineering, information engineering ,business ,China ,0503 education - Abstract
China has become one of the largest oversea student destination countries in recent years. Local universities occupy a large percentage of the total higher education scale in China. Consequently, local universities can contribute significantly to oversea student education. However, local universities of China are still facing some barriers to high-quality oversea student education, including lack of education plans and limited degree of internationalization. We take the international computer majors in School of Computer Engineering (Weifang University) as a case study to investigate on the solutions of conquering these barriers. We formulate specialized education plans and design our method to enhance internationalization. Our solutions have been applied to computer-major international students and contribute to oversea student education in our university.
- Published
- 2021
58. Continuous elevation of procalcitonin in cirrhosis combined with hepatic carcinoma: a case report
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Jiandi Jin, Chengbo Yu, Chunlei Chen, Jun Chen, and Juan Lu
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Liver Cirrhosis ,Male ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Cirrhosis ,Case Report ,Inflammation ,Gastroenterology ,Procalcitonin ,lcsh:Infectious and parasitic diseases ,End Stage Liver Disease ,Sepsis ,03 medical and health sciences ,Liver disease ,0302 clinical medicine ,Internal medicine ,parasitic diseases ,medicine ,Humans ,lcsh:RC109-216 ,Hepatic carcinoma ,Chemoembolization, Therapeutic ,Aged ,business.industry ,Liver Neoplasms ,Bacterial Infections ,medicine.disease ,Endotoxemia ,Infectious Diseases ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Biomarker (medicine) ,030211 gastroenterology & hepatology ,Bacterial infection ,medicine.symptom ,Liver cancer ,business ,hormones, hormone substitutes, and hormone antagonists ,Biomarkers - Abstract
Background Serum levels of procalcitonin (PCT) are considered a useful biomarker for the diagnosis of bacterial infection or inflammation. There are few reports of high PCT levels in end-stage liver disease regardless of bacterial infection. Here, we present a case of extremely high PCT levels (> 100 ng/mL) in a patient with severe cirrhosis combined with hepatic carcinoma. Case presentation A 65-year-old man developed end-stage cirrhosis with hepatic carcinoma. Radiographic imaging showed a massive hepatocellular carcinoma with multiple loci lack of indications of resection. Hence, transcatheter hepatic arterial chemoembolization was performed three times over a period of 4 months. Before and after interventional therapies, the biochemistry laboratory results were only slightly abnormal except for persistently high PCT concentrations (> 100 ng/mL), irrespective of the evidence for bacterial infection or sepsis. Conclusions This case suggests that continuously high levels of PCT (> 100 ng/mL) may be present in advanced liver disease, particularly in complex situations such as decompensated cirrhosis and liver cancer, in the absence of severe infection or sepsis. This knowledge could expand the significance of PCT in liver disease.
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- 2021
59. The Jumonji-C Histone Lysine Demethylase KDM3B Senses Cellular Iron to Regulate Anabolism Through mTORC1
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Jason Shapiro, Hsiang-Chun Chang, Zibo Zhao, Justin Geier, Elizabeth Bartom, Chunlei Chen, Yihan Chen, Adam De Jesus, Zohra Sattar, Farnaz Keyhani-Nejad, Tatsuya Sato, Lucia Ramos-Alonso, Antonia Maria Romero, Maria Teresa Martinez-Pastor, Shang-chuan Jiang, Shiv K. Sah-Teli, Liming Li, David Bentrem, Gary Lopaschuk, Issam Ben-Sahra, Thomas V. O'Halloran, Ali Shilatifard, Sergi Puig, Joy Bergelson, Peppi Koivunen, and Hossein Ardehali
- Published
- 2021
60. Hexokinase 1 cellular localization regulates the metabolic fate of glucose
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Hossein Ardehali, Justin Geier, Trenton Nicioli, Joshua S. Stoolman, Krishna V. Suresh, Samuel E. Weinberg, Lauren Goodman, Adam De Jesus, Kai Xu, Hsiang-Chun Chang, Paulina J Stanczyk, Chunlei Chen, Navdeep S. Chandel, Carolina M. Pusec, Arianne E. Rodriguez, Brian T. Layden, Issam Ben-Sahra, Jason S. Shapiro, Yihan Chen, Kriti P. Shah, and Farnaz Keyhani-Nejad
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Hexokinase ,biology ,Chemistry ,Nitrosylation ,Cell Biology ,Pentose phosphate pathway ,Mitochondrion ,Cell biology ,Mitochondria ,Pentose Phosphate Pathway ,chemistry.chemical_compound ,Mice ,Glucose ,stomatognathic system ,biology.protein ,Animals ,Glycolysis ,Flux (metabolism) ,Molecular Biology ,Glyceraldehyde 3-phosphate dehydrogenase ,Cellular localization - Abstract
The product of hexokinase (HK) enzymes, glucose-6-phosphate, can be metabolized through glycolysis or directed to alternative pathways, such as the pentose phosphate pathway (PPP) to generate anabolic intermediates. However, it is not known what determines the fate of G6P. HK1 contains an N-terminal mitochondrial–binding domain, but its physiologic significance remains unclear. We overexpressed full-length and truncated HK1 in tissue culture and generated mice lacking the HK1 mitochondrial-binding domain (ΔE1HK1). Although ΔE1HK1 mice displayed no overt phenotype, HK1 dislocation from the mitochondria increased glucose flux through the PPP, decreased flux below the level of GAPDH, and induced a hyper-inflammatory response to lipopolysaccharide. The mechanism for the increased PPP flux is through glycolytic block at GAPDH, which is mediated by binding of cytosolic HK1 with S100A8/A9 and increased GAPDH nitrosylation through iNOS. Additionally, human and mouse macrophages from conditions of low-grade inflammation, such as aging and diabetes, displayed an increase in cytosolic HK1 and cytokine production, along with reduced GAPDH activity. Our data indicate that HK1 mitochondrial-binding alters glucose metabolism through regulation of GAPDH.
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- 2022
61. Enhancing traditional Chinese medicine diagnostics: Integrating ontological knowledge for multi-label symptom entity classification
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Hangle Hu, Chunlei Cheng, Qing Ye, Lin Peng, and Youzhi Shen
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biomedical system analysis ,medical informatics ,multi-label entity extraction ,natural language processing ,artificial intelligence ,Biotechnology ,TP248.13-248.65 ,Mathematics ,QA1-939 - Abstract
In traditional Chinese medicine (TCM), artificial intelligence (AI)-assisted syndrome differentiation and disease diagnoses primarily confront the challenges of accurate symptom identification and classification. This study introduces a multi-label entity extraction model grounded in TCM symptom ontology, specifically designed to address the limitations of existing entity recognition models characterized by limited label spaces and an insufficient integration of domain knowledge. This model synergizes a knowledge graph with the TCM symptom ontology framework to facilitate a standardized symptom classification system and enrich it with domain-specific knowledge. It innovatively merges the conventional bidirectional encoder representations from transformers (BERT) + bidirectional long short-term memory (Bi-LSTM) + conditional random fields (CRF) entity recognition methodology with a multi-label classification strategy, thereby adeptly navigating the intricate label interdependencies in the textual data. Introducing a multi-associative feature fusion module is a significant advancement, thereby enabling the extraction of pivotal entity features while discerning the interrelations among diverse categorical labels. The experimental outcomes affirm the model's superior performance in multi-label symptom extraction and substantially elevates the efficiency and accuracy. This advancement robustly underpins research in TCM syndrome differentiation and disease diagnoses.
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- 2024
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62. Etiology of Liver Injury
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Yongtao Li, Chunlei Chen, and Wenrui Wu
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Liver injury ,Pathology ,medicine.medical_specialty ,Chemotherapy ,business.industry ,medicine.medical_treatment ,Ischemia ,food and beverages ,Blood stasis ,Disease ,medicine.disease ,Chronic liver disease ,medicine ,Etiology ,Liver neoplasm ,business - Abstract
Multiple pathogenic factors can lead to varying degrees of liver damage, such as infected with viruses, bacteria, parasites, alcohol, various drugs, enormous liver neoplasm, etc. Heredity and metabolism, a kind of autosomal recessive genetic disease, can also lead to liver damage. Autoimmune liver diseases are a special chronic liver disease with idiopathic etiology. Other factors can also induce liver injury, including malnutrition, Budd–Chiari syndrome, trauma, surgery, shock, chemotherapy, radiotherapy, blood stasis, ischemia, reperfusion, etc.
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- 2020
63. A 4-Channel 10-Gbps/ch CMOS VCSEL Array Driver with on-chip Charge Pumps
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Tianwei Liu, A. Sánchez Rodríguez, C. Liu, Wenyong Zhang, Guangming Huang, Xinyan Huang, Q. Sun, Jingbo Ye, Lingli Zhang, Hong Sun, D. Guo, Jan Troska, D. Gong, Pedro Moreira, S. R. Hou, Chunlei Chen, Szymon Kulis, and L. Xiao
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Materials science ,Physics - Instrumentation and Detectors ,business.industry ,FOS: Physical sciences ,Biasing ,Instrumentation and Detectors (physics.ins-det) ,Laser array ,Radiation ,Vertical-cavity surface-emitting laser ,Headroom (audio signal processing) ,CMOS ,Power consumption ,Optoelectronics ,Detectors and Experimental Techniques ,business ,physics.ins-det ,Voltage - Abstract
We present the design and test results of a 4-channel 10-Gbps/ch Vertical-Cavity Surface-Emitting Laser array driver, the cpVLAD. With on-chip charge-pumps to extend the biasing headroom for the VCSELs needed for low temperature operation and mitigation of the radiation effects. The cpVLAD was fabricated in a 65-nm CMOS technology. The test results show that the cpVLAD is capable of driving VCSELs with forward bias voltages as high as 2.8 V from a 2.5 V power supply. The power consumption of the cpVLAD is 94 mW/ch., Comment: 5 pages, 7 figures
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- 2020
64. Knock Knock: A Binary Human–Machine Interactive Channel for Smartphone with Accelerometer
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Wenteng Xu, Zhipin Gu, Haiyang Wang, Huixiang Zhang, and Chunlei Chen
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Support vector machine ,Naive Bayes classifier ,Gesture recognition ,Computer science ,business.industry ,Sliding window protocol ,Decision tree ,Human–machine system ,Computer vision ,Artificial intelligence ,Accelerometer ,business ,Communication channel - Abstract
A binary human–machine interactive channel for smartphone with accelerometer is proposed in this paper. By comparing and analyzing the advantages and disadvantages of the four binary gestures, the knock gesture is selected as the interactive gesture. Subsequently, we elaborate on the knock gesture-oriented binary human–computer interaction channel. The accelerometer signal is sampled during the interaction process. Three methods including the heuristic algorithm, the support vector machine algorithm, the online sliding window and bottom-up algorithm are used to cut the sampled data into bit signal segment. Three machine learning algorithms including the decision tree, the support vector machine, and the naive Bayesian are separately adopted to transform the cut signal segment into bit information. Finally, our binary human–computer interaction channel is verified by experiments. A higher recognition rate can be achieved only by using traditional machine learning methods.
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- 2020
65. Distribution characteristics and environmental fate of PCBs in marine sediments at different latitudinal regions: Insights from congener profiles
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Xibin Han, Xinkai Li, Zhaochao Deng, Ning Zhang, Hanghai Zhou, Chunlei Chen, Chunfang Zhang, and Heng Wang
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0106 biological sciences ,Pollution ,China ,Geologic Sediments ,South china ,media_common.quotation_subject ,Microbial transformation ,Antarctic Regions ,010501 environmental sciences ,Aquatic Science ,Oceanography ,01 natural sciences ,Latitude ,Prospective Studies ,0105 earth and related environmental sciences ,media_common ,organic chemicals ,010604 marine biology & hydrobiology ,food and beverages ,Contamination ,Polychlorinated Biphenyls ,Congener ,Environmental chemistry ,Environmental science ,Bay ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
Sediments were sampled from Hangzhou Bay (HB), the South China Sea (SCS), and Antarctica (AZ) to better understand the distribution characteristics and environmental fate of polychlorinated biphenyls (PCBs) at different latitudes. Numerous PCB congeners (68) were detected among the sampling sites, supporting the ubiquity of PCB congeners. High and low chlorinated congeners dominated the PCB profiles of AZ and SCS, respectively, whereas the PCB homologues were evenly distributed in the HB. As a fraction of low chlorinated PCBs originates from an exogenous input, the low mean ratios of ∑Tetra-CBs to ∑PCBs and ∑Tetra-CBs to the sum of ∑Tri- and ∑Di-CBs suggest that microbial transformation of PCBs is weak in marine surface sediments, if any occurs at all. Furthermore, PCB contamination levels in marine sediments may be primarily influenced by latitude rather than pollution sources. Thus, the findings of this study suggest that Antarctica is becoming a prospective hotspot for PCBs.
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- 2020
66. Complete-Genome Sequencing and Comparative Genomic Characterization of an IMP-4 Producing
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Xiaohui, Chi, Jing, Guo, Yanzi, Zhou, Tingting, Xiao, Hao, Xu, Tao, Lv, Chunlei, Chen, Jian, Chen, and Beiwen, Zheng
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Citrobacter freundii ,integron ,whole-genome sequencing ,bacteria ,SNP ,biochemical phenomena, metabolism, and nutrition ,CPE ,bacterial infections and mycoses ,IncN ,Original Research - Abstract
Background Citrobacter freundii is the most common class of pathogens in the genus Citrobacter and is an important pathogen associated with certain underlying diseases or immune dysfunction. The aim of this study was to elucidate the resistance mechanism of clinically derived carbapenem-resistant C. freundii isolate and to characterize the genetic environment and delivery pattern of the IncN1 plasmid carrying the blaIMP-4 gene from C. freundii isolate. Materials and Methods We identified a clinical isolate of C. freundii L91 carrying blaIMP-4 and performed phylogenetic analysis by whole-genome sequencing. The complete genomic sequence of L91 was obtained using the Illumina HiSeq 4000-PE150 and PacBio RS II platforms. Antimicrobial susceptibility testing was determined by the VITEK 2 system. Plasmid characteristics were presented by S1-pulsed-field gel electrophoresis (PFGE), Southern blotting and conjugation experiments. Results S1-PFGE, Southern blot and conjugation assay confirmed the presence of blaIMP-4 genes on a conjugative plasmid in this isolate. C. freundii L91 and transconjugant L91-E. coli 600 strains both showed resistance to carbapenems. In silico analysis further showed that pIMP-4-L91 is an IncN1 plasmid with a length of 51,042 bp. Furthermore, blaIMP-4 gene was found encoded in the blaIMP-4-qacG2-aacA4-catB3 cassette array within a class 1 integron. A conserved structure sequence (ΔISKpn27-blaIMP-4-ΔISSen2-hp-hp-IS6100) was found in the upstream and downstream of the blaIMP-4. Conclusion We performed a comprehensive phylogenetic analysis of carbapenemase-resistant C. freundii and elucidated the resistance mechanism of clinically derived C. freundii L91. Not only that, we also found that the blaIMP-4 gene is located on the IncN1 plasmid and has a horizontal transfer function and a certain ability to spread. To lower the risk of the dissemination of such C. freundii isolates in clinical settings, more surveillance is needed in the future.
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- 2020
67. Your Knock Is My Command: Binary Hand Gesture Recognition on Smartphone with Accelerometer
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Huixiang Zhang, Yonghui Zhang, Wenteng Xu, Liang Bai, and Chunlei Chen
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Dynamic time warping ,Article Subject ,Computer Networks and Communications ,Computer science ,Speech recognition ,Decision tree ,020206 networking & telecommunications ,TK5101-6720 ,02 engineering and technology ,Expression (mathematics) ,Computer Science Applications ,Support vector machine ,Set (abstract data type) ,Naive Bayes classifier ,Gesture recognition ,Telecommunication ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Gesture - Abstract
Motion-based hand gesture is an important scheme to allow users to invoke commands on their smartphones in an eyes-free manner. However, the existing scheme is facing some problems. On the one hand, the expression ability of one single gesture is limited. As a result, a gesture set consisting of multiple gestures is typically adopted to represent different commands. Users must memorize all gestures in order to make interaction successfully. On the other hand, the design of gestures needs to be complicated to express diverse intensions. However, complex gestures are difficult to learn and remember. In addition, complex gestures set a high recognition barrier to smart APPs. This leads to an imbalance problem. Different gestures have different recognition accuracy levels, which may result in instability of recognition precision in practical applications. To address these problems, this paper proposes a novel scheme using binary motion gestures. Only two simple gestures are required to express bit “0” and “1,” and rich information can be expressed through the permutation and combination of the two binary gestures. Firstly, four kinds of candidate binary gestures are evaluated for eyes-free interactions. Then, an online signal cutting and merging algorithm is designed to split accelerometer signals sequence into multiple separate gesture signal segments. Next, five algorithms, including Dynamic Time Warping (DTW), Naive Bayes, Decision Tree, Support Vector Machine (SVM), and Bidirectional Long Short-Term Memory (BLSTM) Network, are adopted to recognize these segments of knock gestures. The BLSTM achieves the top performance in terms of both recognition accuracy and recognition imbalance. Finally, an Android application is developed to illustrate the usability of the proposed binary gestures. As binary gestures are much simpler than traditional hand gestures, they are more efficient and user-friendly. Our scheme eliminates the imbalance problem and achieves high recognition accuracy.
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- 2020
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68. Effect of Grout Age on Mechanical Behaviors of Grouted Sleeve Connections
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Huawei Xiang, Yutong Wang, Chunlei Chen, and Jinfeng Wang
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Published
- 2022
69. Optimizing data transmission and access of the incremental clustering algorithm using CUDA: A case study
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Lei Wang, Chunlei Chen, Jinkui Hou, Jiangyan Dai, Peng Zhang, Yonghui Zhang, and Chengduan Wang
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020203 distributed computing ,Computer science ,General Engineering ,02 engineering and technology ,computer.software_genre ,020202 computer hardware & architecture ,Computer Science Applications ,Computational Mathematics ,CUDA ,0202 electrical engineering, electronic engineering, information engineering ,Data mining ,Cluster analysis ,computer ,Data transmission - Published
- 2018
70. Genomic characterisation of a colistin-resistant Klebsiella pneumoniae ST11 strain co-producing KPC-2, FloR, CTX-M-55, SHV-12, FosA and RmtB causing a lethal infection
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Xiaoliang, Wu, Huiming, Han, Chunlei, Chen, and Beiwen, Zheng
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- 2019
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71. Interpersonal Meaning of Chinese Original Picture Books: A Multimodal Analysis Based on New Visual Grammar
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Chunlei, Chen, primary
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- 2021
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72. Enhanced bioremediation of diesel oil-contaminated seawater by a biochar-immobilized biosurfactant-producing bacteria Vibrio sp. LQ2 isolated from cold seep sediment
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Lijia Jiang, Keliang Li, Qinglin Xie, Xiaoyun Lin, Hanghai Zhou, Chunlei Chen, and Chunfang Zhang
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Environmental Engineering ,010504 meteorology & atmospheric sciences ,biology ,Chemistry ,010501 environmental sciences ,Bacterial growth ,Biodegradation ,biology.organism_classification ,01 natural sciences ,Pollution ,Vibrio ,Diesel fuel ,Biodegradation, Environmental ,Bioremediation ,Charcoal ,Environmental chemistry ,Biochar ,Environmental Chemistry ,Seawater ,Waste Management and Disposal ,Gasoline ,Bacteria ,0105 earth and related environmental sciences - Abstract
This study investigated the effect of immobilized biosurfactant-producing bacteria on the bioremediation of diesel oil-contaminated seawater. Initially, a biosurfactant-producing bacterium, LQ2, was isolated from a marine cold-seep region, and identified as Vibrio sp. The biosurfactant produced by LQ2 was characterized as a phospholipid, exhibiting high surface activity with strong stability. Meanwhile, the inoculation of biochar-immobilized LQ2 demonstrated superior efficiency in removing diesel oil (94.7%, reduction from 169.2 mg to 8.91 mg) over a seven-day period compared to free-cell culture (54.4%), through both biodegradation and adsorption. In addition, the microbial growth and activity were greatly enhanced with the addition of immobilized LQ2. Further experiment showed that degradation-related genes, alkB and CYP450–1, were 3.8 and 15.2 times higher in the immobilized LQ2 treatment, respectively, than those in the free cell treatment. The findings obtained in this study suggest the feasibility of applying immobilized biosurfactant-producing bacteria, namely LQ2, in treating diesel oil-contaminated seawater.
- Published
- 2021
73. Volume deformation of steam-cured concrete with fly ash during and after steam curing
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Chunlei Chen, Hua Fu, Tengfei Guo, Wenqiang Zuo, Penggang Wang, Haitao Zhao, and Li Tian
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Materials science ,Curing (food preservation) ,Tension (physics) ,food and beverages ,Humidity ,Building and Construction ,Deformation (meteorology) ,complex mixtures ,humanities ,Degree (temperature) ,Compressive strength ,Fly ash ,General Materials Science ,Composite material ,Civil and Structural Engineering ,Shrinkage - Abstract
Steam-cured concrete presents high compressive strength at an early age. However, understanding regarding temperature-induced deformation development in steam–cured concrete with fly ash is limited. In the present research, the volume deformation of fly ash concrete experienced steam curing stage at an early age has been carried out. Volume deformation of concrete without fly ash is also studied as a comparison. In order to obtain the in situ property changes of steam-cured concrete, a strain-temperature-humidity integrated acquisition system was used to continuously record the interior strain, temperature, and humidity evolutions of the sample. The test results show that the autogenous shrinkage occurs at the constant temperature stage of steam curing, and the shrinkage after steam curing is mainly because of the drying effect. The addition of fly ash can increase the development of shrinkage in steam curing, but it is beneficial to shrinkage after steam curing. And the hydration degree prediction development model of steam-cured cement paste is proposed. Finally, a micromechanical model is proposed based on the capillary tension produced by pores, using interior humidity and hydration degree as the driving parameters, which decently predicts the total shrinkage and autogenous shrinkage of concrete specimens after steam curing.
- Published
- 2021
74. Performance and microbial community analysis of a bio-contact oxidation reactor during the treatment of low-COD and high-salinity oilfield produced water
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Kuiyong Bu, Hanghai Zhou, Li Pingyuan, Lijia Jiang, Chunfang Zhang, Chunlei Chen, Xiaoyun Lin, and Zhou Shaoxiong
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0106 biological sciences ,Salinity ,Environmental Engineering ,Bioengineering ,Wastewater ,010501 environmental sciences ,Waste Disposal, Fluid ,01 natural sciences ,Bioreactors ,010608 biotechnology ,Oil and Gas Fields ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Pollutant ,Rhodobacter ,biology ,Renewable Energy, Sustainability and the Environment ,Microbiota ,Roseovarius ,Community structure ,Water ,General Medicine ,biology.organism_classification ,Pulp and paper industry ,Produced water ,Microbial population biology ,Environmental science - Abstract
The multistage bio-contact oxidation reactor (BCOR) is a widely used biological strategy to treat wastewater, however, little is known about the performance and microbial community information of BCOR during the treatment of low-COD and high-salinity oilfield produced water. In this study, the performance of a multistage BCOR in treating produced water was investigated. The result suggested the BCOR could efficiently remove COD, BOD5, NH4+-N, and oil pollutants. Besides, high-throughput sequencing analysis revealed that oil content was the main variable in shaping the community structure. The highest total relative abundance of potential pollutants degraders in first BCOR stage suggested significant role of this stage in pollutants removal. In addition, the correlation analysis disclosed the key functional genera during the degradation process, including Rhodobacter, Citreibacter, and Roseovarius. Moreover, network analysis revealed that the microbial taxa within same module had strong ecological linkages and specific functions.
- Published
- 2021
75. Study on Radial Clearance Sealing Performance of Graphite Ring
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Xianjun, Zhou, primary, Chunlei, Chen, additional, Jianhua, Li, additional, and Yanze, Wu, additional
- Published
- 2020
- Full Text
- View/download PDF
76. Abstract 424: Loss of Sirt2 Protects Against Pressure Overload- and Ischemic Reperfusion Injury-induced Cardiac Dysfunction
- Author
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Sato, Teruki, primary, Yan, Xiaoyan, additional, Chang, Hsiang-Chun, additional, Chunlei, Chen, additional, Shapiro, Jason S, additional, and Ardehali, Hossein, additional
- Published
- 2020
- Full Text
- View/download PDF
77. Microbial nitrogen removal in synthetic aquaculture wastewater by fixed-bed baffled reactors packed with different biofilm carrier materials
- Author
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Qiang Xu, Chunlei Chen, Xinkai Li, Rui Wang, Chunfang Zhang, and Dongdong Zhang
- Subjects
0106 biological sciences ,Environmental Engineering ,Denitrification ,Hydraulic retention time ,Nitrogen ,Bioengineering ,Aquaculture ,Wastewater ,010501 environmental sciences ,01 natural sciences ,Nitrogen removal ,Aquaculture wastewater ,Denitrifying bacteria ,Bioreactors ,010608 biotechnology ,Waste Management and Disposal ,0105 earth and related environmental sciences ,biology ,Renewable Energy, Sustainability and the Environment ,Chemistry ,Biofilm ,General Medicine ,biology.organism_classification ,Pulp and paper industry ,Nitrification ,Biofilms ,Chain reaction ,Bacteria - Abstract
Fixed-bed baffled reactors packed with carbon fiber (CFBR), polyurethane, or non-woven fabrics were developed to support microbial nitrification–denitrification reactions for nitrogen removal from synthetic aquaculture wastewater. The CFBR showed the best performance, with a short hydraulic retention time and low C/N ratio. Microbial communities in the reactor’s biofilms and deposited sludge were analyzed using high-throughput sequencing and quantitative polymerase chain reactions. The biofilms efficiently enriched the nitrifying and denitrifying bacteria in the CFBR. Moreover, bacteria capable of denitrification under aerobic conditions were detected in the aerobic chamber biofilm, showing positive correlations with the main nitrifiers and denitrifiers, which provides potential synergistic interactions for simultaneous nitrification–denitrification in the aerobic chamber. A network analysis revealed that the CFBR had more complex cooperative interactions than others. This study provides insights into the influence of different carrier materials on biofilm formation, proving that the CFBR has potential applications in aquaculture wastewater treatment.
- Published
- 2021
78. Radiation resistance of poly(methyl methacrylate)/reduced graphene oxide nanocomposites fabricated through latex mixing and in situ reduction
- Author
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Dongge Zhang, Yu Lin, Yaohua Liu, Guozhang Wu, and Chunlei Chen
- Subjects
Materials science ,General Chemical Engineering ,Oxide ,macromolecular substances ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Industrial and Manufacturing Engineering ,law.invention ,chemistry.chemical_compound ,law ,Polymer chemistry ,Environmental Chemistry ,Irradiation ,Methyl methacrylate ,Radiation resistance ,Nanocomposite ,Graphene ,technology, industry, and agriculture ,General Chemistry ,021001 nanoscience & nanotechnology ,Poly(methyl methacrylate) ,0104 chemical sciences ,chemistry ,Chemical engineering ,visual_art ,visual_art.visual_art_medium ,0210 nano-technology ,Dispersion (chemistry) - Abstract
We present a facile, environmentally friendly approach to fabricate high-radiation-resistance poly(methyl methacrylate)/reduced graphene oxide (PMMA/RGO) composites through latex mixing of anionic PMMA latex particles and graphene oxide dispersion followed by coagulation and in situ hydrazine reduction. Morphological observation reveals the highly uniform dispersion of RGO nanosheets in the PMMA matrix. The dynamic mechanical properties demonstrate that the radiation-induced cross linking and chain scission of PMMA chains are significantly delayed in PMMA/RGO nanocomposites compared with that in pure PMMA irradiated at low and high doses, respectively. Additionally, the incorporation of RGO nanosheets delays the thermal oxidative degradation of the PMMA matrix. This delay is attributed to the fact that RGO can act as a radical scavenger, as confirmed by electron paramagnetic resonance spectroscopy analysis. The physical barrier effect of RGO provides a tortuous path for the diffusion of oxygen molecules and consequently leads to a decrease in peroxy radical concentrations. The synergistic effects keep the graphene-based materials mechanically and thermally stable in the irradiation environment. These findings provide a new strategy for the design of radiation-resistant nanocomposites, which can be considered promising candidates for protective materials in nuclear industrial and aerospace fields.
- Published
- 2017
79. A Method to Remotely Track a Magnetic Target Using a Scalar Magnetometer Array
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Chong Kang, Xuejun Liu, Chunlei Chen, Peng Cheng, Zhang Xiaojun, and Liming Fan
- Subjects
010302 applied physics ,Optimization problem ,Article Subject ,Magnetometer ,Computer science ,Orientation (computer vision) ,Scalar (physics) ,Particle swarm optimization ,010502 geochemistry & geophysics ,Tracking (particle physics) ,01 natural sciences ,law.invention ,Control and Systems Engineering ,law ,Position (vector) ,lcsh:Technology (General) ,0103 physical sciences ,Trajectory ,lcsh:T1-995 ,Electrical and Electronic Engineering ,Instrumentation ,Algorithm ,0105 earth and related environmental sciences - Abstract
The orientation of a vector magnetic sensor can affect the measurement accuracy of magnetic anomaly, thereby increasing the localization error of a magnetic target. Compared with vector magnetic sensor, the measurement of the scalar magnetic sensor is almost not influenced by its orientation. Therefore, we present a method for tracking the magnetic target with a static scalar magnetometer array. In this study, the magnitude of the target’s magnetic moment is a key parameter. We isolate it and formulate an optimization problem based on it to estimate the position and magnetic parameters of the target. To calculate the solution of this optimization problem, a dedicated particle swarm optimization (PSO) algorithm is developed. Then, we define a quality index to evaluate the solution calculated by the optimization problem. The proposed method was validated by the simulation and the real data collected when an SUV car was passing by the array on a straight path. The results show that the tracked trajectory is very close to the true trajectory and the quality index can be used as a criterion to allow accepting or rejecting the localization of the target.
- Published
- 2017
80. On the Accuracy and Parallelism of GPGPU-Powered Incremental Clustering Algorithms
- Author
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Li He, Chunlei Chen, Lei Wang, Huixiang Zhang, and Hao Zheng
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Theoretical computer science ,Article Subject ,General Computer Science ,Computer science ,Data parallelism ,General Mathematics ,General Neuroscience ,Correlation clustering ,Constrained clustering ,Task parallelism ,02 engineering and technology ,General Medicine ,lcsh:Computer applications to medicine. Medical informatics ,lcsh:RC321-571 ,Data stream clustering ,020204 information systems ,0202 electrical engineering, electronic engineering, information engineering ,lcsh:R858-859.7 ,020201 artificial intelligence & image processing ,Granularity ,General-purpose computing on graphics processing units ,Cluster analysis ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Research Article - Abstract
Incremental clustering algorithms play a vital role in various applications such as massive data analysis and real-time data processing. Typical application scenarios of incremental clustering raise high demand on computing power of the hardware platform. Parallel computing is a common solution to meet this demand. Moreover, General Purpose Graphic Processing Unit (GPGPU) is a promising parallel computing device. Nevertheless, the incremental clustering algorithm is facing a dilemma between clustering accuracy and parallelism when they are powered by GPGPU. We formally analyzed the cause of this dilemma. First, we formalized concepts relevant to incremental clustering like evolving granularity. Second, we formally proved two theorems. The first theorem proves the relation between clustering accuracy and evolving granularity. Additionally, this theorem analyzes the upper and lower bounds of different-to-same mis-affiliation. Fewer occurrences of such mis-affiliation mean higher accuracy. The second theorem reveals the relation between parallelism and evolving granularity. Smaller work-depth means superior parallelism. Through the proofs, we conclude that accuracy of an incremental clustering algorithm is negatively related to evolving granularity while parallelism is positively related to the granularity. Thus the contradictory relations cause the dilemma. Finally, we validated the relations through a demo algorithm. Experiment results verified theoretical conclusions.
- Published
- 2017
81. Occurrence and Genomic Characterization of Two MCR-1-Producing Escherichia coli Isolates from the Same Mink Farmer
- Author
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Chunlei Chen, Huiming Han, Chen Huang, Jing Zhang, Yonghong Xiao, Lihua Guo, Beiwen Zheng, Xiawei Jiang, Xiao Yu, and Hao Xu
- Subjects
0301 basic medicine ,Imipenem ,Genotype ,pacbio ,030106 microbiology ,lcsh:QR1-502 ,Observation ,Microbial Sensitivity Tests ,medicine.disease_cause ,Microbiology ,lcsh:Microbiology ,Clinical Science and Epidemiology ,03 medical and health sciences ,Plasmid ,biology.animal ,Drug Resistance, Multiple, Bacterial ,Occupational Exposure ,medicine ,Pulsed-field gel electrophoresis ,Disease Transmission, Infectious ,Escherichia coli ,Animals ,Humans ,Typing ,Mink ,Animal Husbandry ,Molecular Biology ,farmer ,Escherichia coli Infections ,Genetics ,esbls ,Farmers ,biology ,Escherichia coli Proteins ,coexistence ,mink ,mcr-1.12 ,QR1-502 ,Electrophoresis, Gel, Pulsed-Field ,030104 developmental biology ,Multilocus sequence typing ,MCR-1 ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug ,Multilocus Sequence Typing ,Plasmids - Abstract
Colistin resistance is a real threat for both human and animal health. The mobile colistin resistance gene mcr has contributed to the persistence and transmission of colistin resistance at the interfaces of animals, humans, and ecosystems. Although mcr genes have usually been recovered from food animals, patients, and healthy humans, transmission of mcr genes at the animal-human interface remains largely unknown. This was the first study to isolate and characterize MCR-producing isolates from mink, as well as to report the coexistence of two different MCR-1 producers in the same farmer. The characterization and analysis of two MCR-1-producing E. coli isolates may have important implications for comprehension of the transmission dynamics of these bacteria. We emphasize the importance of improved multisectorial surveillance of colistin-resistant E. coli in this region., The spread of colistin resistance gene mcr-1 at the animal-human interface remains largely unknown. This work aimed to investigate the molecular characteristics of two extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli strains with mcr-1, i.e., strains H8 and H9, isolated from the same mink farmer. In this study, five mcr-positive E. coli strains were isolated from the mink farm. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) identified two genetically unrelated MCR-1 producers (H8 and H9) from the same farmer and two clonally related MCR-1-positive isolates (M5 and M6) from two different mink samples. Additionally, a mcr-1 variant, designated mcr-1.12, was identified in isolate M4. MIC determination revealed that all of the MCR-producing strains exhibited multiresistant phenotypes but showed susceptibility to imipenem, meropenem, amikacin, and tigecycline. Replicon typing showed that mcr-1 was associated with IncHI2 plasmids in 4 cases, while the gene was located on an IncI2 plasmid in 1 case. PacBio sequencing and plasmid analysis confirmed that the mcr-1 gene was located on an ∼204-kb IncHI2 plasmid in H8 and was carried by an ∼61-kb IncI2 plasmid in H9. To our knowledge, this work represents the first report of the occurrence of MCR-producing isolates from mink. Moreover, our report also describes the coexistence of two different MCR-1 producers in the same farmer. It highlights that fur farms can be reservoirs of mcr-1 genes. The identification of mcr-carrying plasmids on a fur farm is of potential public health importance, as it suggests that mcr is widespread in the animal husbandry industry. IMPORTANCE Colistin resistance is a real threat for both human and animal health. The mobile colistin resistance gene mcr has contributed to the persistence and transmission of colistin resistance at the interfaces of animals, humans, and ecosystems. Although mcr genes have usually been recovered from food animals, patients, and healthy humans, transmission of mcr genes at the animal-human interface remains largely unknown. This was the first study to isolate and characterize MCR-producing isolates from mink, as well as to report the coexistence of two different MCR-1 producers in the same farmer. The characterization and analysis of two MCR-1-producing E. coli isolates may have important implications for comprehension of the transmission dynamics of these bacteria. We emphasize the importance of improved multisectorial surveillance of colistin-resistant E. coli in this region.
- Published
- 2019
82. CD4+ T cell exhaustion revealed by high PD-1 and LAG-3 expression and the loss of helper T cell function in chronic hepatitis B
- Author
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Yu Chen, Xuefen Li, Qiaoyun Zhu, Jiaqi Bao, Chunlei Chen, Yuejiao Dong, and Lu Zhang
- Subjects
0301 basic medicine ,lcsh:Immunologic diseases. Allergy ,Adult ,CD4-Positive T-Lymphocytes ,Male ,Allergy ,Programmed death 1 (PD-1) ,Hepatitis B virus ,medicine.medical_treatment ,T cell ,Immunology ,Programmed Cell Death 1 Receptor ,medicine.disease_cause ,Lymphocyte Activation ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,Antineoplastic Agents, Immunological ,Hepatitis B, Chronic ,Liver Function Tests ,Antigens, CD ,medicine ,Humans ,Secretion ,Cytokine ,Chronic HBV infection ,Chemistry ,T-Lymphocytes, Helper-Inducer ,Viral Load ,medicine.disease ,Lymphocyte Activation Gene 3 Protein ,CD4+ T cells ,Blockade ,030104 developmental biology ,medicine.anatomical_structure ,Gene Expression Regulation ,Cytokines ,Cytokine secretion ,Female ,Lymphocyte activation gene-3 (LAG-3) ,lcsh:RC581-607 ,Inhibitory molecules ,030215 immunology ,Research Article - Abstract
Background Immune inhibitory receptors play an important role in chronic infections. However, little is known about their role in hepatitis B virus (HBV) infection. Here, we analyzed the relationship between programmed death-1 (PD-1) and lymphocyte activation gene-3 (LAG-3) expression on CD4+ T cells and HBV disease progression. Results PD-1 and LAG-3 expression was significantly higher on CD4+ T cells from HBV patients than on those from the HCs. In addition, a significant positive correlation was found between the PD-1 and LAG-3 expression levels and the ALT(alanine aminotransferase) level. CD4+ T cell function was inhibited by high PD-1 and LAG-3 levels, and CD4+ T cells with high PD-1 and LAG-3 expression lost the ability to secrete IFN-γ, IL-2 and TNF-α. Furthermore, blockade of the PD-1 and LAG-3 pathways reversed the damage to CD4+ T cell proliferation and cytokine secretion. Conclusions CD4+ T cell exhaustion during chronic HBV had high PD-1 and LAG-3 expression and the absence of helper T cell cytokines, including IFN-γ, IL-2 and TNF-α. After blocking PD-L1 and LAG-3, CD4+ T cell function in chronic hepatitis B patients was partially restored.
- Published
- 2019
83. Magnetism Study in Transition Metal Doped Superatoms: TMLi12(TM=Sc-Fe)
- Author
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Jianmei Shao, Chunlei Chen, and Lijuan Yan
- Subjects
Quantitative Biology::Biomolecules ,Materials science ,Magnetic moment ,Condensed matter physics ,Series (mathematics) ,Icosahedral symmetry ,Magnetism ,Binding energy ,General Medicine ,equipment and supplies ,Hybrid functional ,Transition metal ,Physics::Atomic and Molecular Clusters ,Density functional theory ,human activities - Abstract
Through unbiased global optimization and density functional theory method, a series of stable icosahedral magnetic...
- Published
- 2019
84. Sirtuin 2 regulates cellular iron homeostasis via deacetylation of transcription factor NRF2
- Author
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Lisa D. Wilsbacher, Hsiang-Chun Chang, David Gius, Athanassios Vassilopoulos, Seong Hoon Park, Paul W. Burridge, Konrad T Sawicki, Xiaoyan Yang, Jason S. Shapiro, Chunlei Chen, Meng Shang, Mitchell D. Knutson, Supak Jenkitkasemwong, Conrad L. Epting, and Hossein Ardehali
- Subjects
Transcriptional Activation ,0301 basic medicine ,NF-E2-Related Factor 2 ,Iron ,Gene Expression ,Biology ,SIRT2 ,Epigenesis, Genetic ,60602 Animal Physiology - Cell ,03 medical and health sciences ,Sirtuin 2 ,Gene expression ,medicine ,Animals ,Homeostasis ,Humans ,Viability assay ,Cation Transport Proteins ,Transcription factor ,Mice, Knockout ,Protein Stability ,Acetylation ,Hep G2 Cells ,General Medicine ,Metabolism ,Iron deficiency ,medicine.disease ,Cell biology ,HEK293 Cells ,030104 developmental biology ,Liver ,Biochemistry ,FOS: Biological sciences ,Sirtuin ,biology.protein ,Protein Processing, Post-Translational ,Research Article - Abstract
SIRT2 is a cytoplasmic sirtuin that plays a role in various cellular processes, including tumorigenesis, metabolism, and inflammation. Since these processes require iron, we hypothesized that SIRT2 directly regulates cellular iron homeostasis. Here, we have demonstrated that SIRT2 depletion results in a decrease in cellular iron levels both in vitro and in vivo. Mechanistically, we determined that SIRT2 maintains cellular iron levels by binding to and deacetylating nuclear factor erythroid-derived 2-related factor 2 (NRF2) on lysines 506 and 508, leading to a reduction in total and nuclear NRF2 levels. The reduction in nuclear NRF2 leads to reduced ferroportin 1 (FPN1) expression, which in turn results in decreased cellular iron export. Finally, we observed that Sirt2 deletion reduced cell viability in response to iron deficiency. Moreover, livers from Sirt2-/- mice had decreased iron levels, while this effect was reversed in Sirt2-/- Nrf2-/- double-KO mice. Taken together, our results uncover a link between sirtuin proteins and direct control over cellular iron homeostasis via regulation of NRF2 deacetylation and stability.
- Published
- 2019
- Full Text
- View/download PDF
85. Connection Pattern Based Android Network Traffic Clustering
- Author
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Yonghui Zhang, Peng Zhang, Huixiang Zhang, Ming Qi, and Chunlei Chen
- Subjects
business.industry ,Computer science ,Feature extraction ,Encryption ,computer.software_genre ,Flow network ,Data mining ,Android (operating system) ,Information gain ,Cluster analysis ,business ,Communications protocol ,computer ,Filter algorithm - Abstract
Network traffic clustering plays a fundamental role in network flow analysis. Existing Android network traffic clustering methods have three shortages. First, these methods always focus on partial features, such as port numbers, with the absence of holistic features. Second, existing methods sometimes fail to work if payload of one network package is encrypted. Third, some methods are valid only for several specific application-layer network protocols. To handle these inefficiencies, we adopted network-connection-pattern based features to facilitate Android network traffic clustering. First, a record platform was constructed. This platform executed 575 Android applications and recorded network traffic. Second, we obtained input datasets of clustering through the record platform and extracted features based on network connection pattern. Then, we clustered the input datasets. Finally, we employed Information Gain algorithm and Fast Correlation-Based Filter algorithm separately to rank contributions of features according to the clustering results. Experiments show that the network-connection-pattern-based features lead to more efficient clustering result than the port-number-based features.
- Published
- 2018
86. Abundance, diversity, and community composition of anammox bacteria in sediments of Xiangshan Bay, China
- Author
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Lieyu Tian, Chunlei Chen, Jingjing Li, Dongdong Zhang, Rui Wang, Yan Sheng, and Chunfang Zhang
- Subjects
0106 biological sciences ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Ecology ,biology ,Chemistry ,010604 marine biology & hydrobiology ,Estuary ,Aquatic Science ,biology.organism_classification ,01 natural sciences ,Salinity ,Anammox ,Abundance (ecology) ,Environmental chemistry ,Scalindua ,Animal Science and Zoology ,Nitrogen cycle ,Bay ,Ecology, Evolution, Behavior and Systematics ,Bacteria ,0105 earth and related environmental sciences - Abstract
Xiangshan Bay (XSB) is a typical semi-closed bay rich in dissolved inorganic nitrogen and anammox is one of the important processes of nitrogen cycle. The anammox bacterial abundance and diversity in XSB sediments was investigated. Five known genera were detected based on the anammox bacterial 16S rRNA gene, namely, Ca. Scalindua, Ca. Brocadia, Ca. Kuenenia, Ca. Jettenia, and Ca. Anammoxoglobus, and hzo genes affiliating with Ca. Scalindua were also discovered. The anammox bacterial 16S rRNA and hzo genes in the sediments varied from 2.10 × 106 to 2.18 × 107 and from 2.90 × 106 to 5.48 × 108 copies/g (fresh weight), respectively. Pearson correlation analysis demonstrated that the abundance of the hzo gene was positively correlated with the concentration of NH 4 + but negatively correlated with salinity and pH. Redundancy analysis showed that salinity, dissolved oxygen, and temperature were the three main factors influencing the community composition of anammox bacteria obtained by the anammox bacterial 16S rRNA gene. These findings help us to further understand the distribution and community composition of anammox bacteria in estuary sediments.
- Published
- 2021
87. Volume Deformation of Steam-Cured Concrete with Slag during and after Steam Curing
- Author
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Chonggen Pan, Penggang Wang, Li Tian, Hua Fu, Chunlei Chen, Han Xiaofeng, and Gege Li
- Subjects
Materials science ,Curing (food preservation) ,shrinkage model ,hydration model ,0211 other engineering and technologies ,020101 civil engineering ,Young's modulus ,02 engineering and technology ,Deformation (meteorology) ,lcsh:Technology ,complex mixtures ,Article ,slag ,0201 civil engineering ,steam-cured concrete ,symbols.namesake ,021105 building & construction ,Hydration reaction ,autogenous shrinkage ,General Materials Science ,Composite material ,lcsh:Microscopy ,Elastic modulus ,lcsh:QC120-168.85 ,Shrinkage ,lcsh:QH201-278.5 ,lcsh:T ,Tension (physics) ,technology, industry, and agriculture ,food and beverages ,humanities ,lcsh:TA1-2040 ,symbols ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,Slag (welding) ,lcsh:Engineering (General). Civil engineering (General) ,lcsh:TK1-9971 - Abstract
In order to better predict the development of shrinkage deformation of steam-cured concrete mixed with slag, a deformation-temperature-humidity integrated model test, a hydration heat test, and an elastic modulus test were performed. The effects of the steam-curing process and the content of slag on shrinkage deformation, hydration degree and elastic modulus of concrete were studied. The results indicate that during the steam-curing process, the concrete has an “expansion-shrinkage” pattern. After the steam curing, the deformation of concrete is dominated by drying shrinkage. After the addition of slag, the shrinkage deformation of steam-cured concrete is increased. The autogenous shrinkage increases by 0.5–12%, and the total shrinkage increases by 1.5–8% at 60 days. At the same time, slag reduces the hydration degree of steam-cured concrete and modulus of elasticity. A prediction model for the hydration degree of steam-cured concrete is established, which can be used to calculate the degree of hydration at any curing age. Based on the capillary tension generated by the capillary pores in concrete, an integrated model of autogenous shrinkage and total shrinkage is established with the relative humidity directly related to the water loss in the concrete as the driving parameter. Whether the shrinkage deformation is caused by hydration reaction or the external environment, this model can better predict the shrinkage deformation of steam-cured concrete.
- Published
- 2021
88. W layer thickness dependence of the spin–orbit effective fields in NiFe/W bilayers
- Author
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Shufa Li, Tao Zhu, Hui Wang, and Chunlei Chen
- Subjects
010302 applied physics ,Materials science ,Condensed matter physics ,Field (physics) ,Bilayer ,General Physics and Astronomy ,02 engineering and technology ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,021001 nanoscience & nanotechnology ,01 natural sciences ,Magnetization ,Ferromagnetism ,0103 physical sciences ,Orbit (dynamics) ,Spin Hall effect ,Condensed Matter::Strongly Correlated Electrons ,0210 nano-technology ,Rashba effect ,Spin-½ - Abstract
Spin–orbit torques (SOTs) generated by in-plane current injection in a ferromagnetic metal (FM)/heavy metal (HM) bilayer offers a new route to electrically manipulate magnetization. Here, we report on two sizable spin–orbit field contributions from the spin Hall effect and Rashba effect in NiFe/W bilayers by using the planar Hall effect. Both spin–orbit fields decrease with increasing W layer thickness. Importantly, the spin–orbit field contributing from the spin Hall effect decreases faster than the one from the Rashba effect as the thickness of W layer increases, leading to the sign change of the field-like torque at thicker W. Our results illustrate the co-contributions of the Rashba effect and the spin Hall effect to the field-like SOT in NiFe/W bilayer giving more insight into the effect of the field-like SOT in a FM/HM bilayer.
- Published
- 2021
89. Study on the Image Retargeting by Using Semantic Concepts
- Author
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Lei Wang and ChunLei Chen
- Subjects
Seam carving ,Computer science ,business.industry ,Signal Processing ,0202 electrical engineering, electronic engineering, information engineering ,020207 software engineering ,Computer vision ,02 engineering and technology ,Artificial intelligence ,business - Published
- 2016
90. Reduction in mitochondrial iron alleviates cardiac damage during injury
- Author
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Meng Shang, Sathyamangla Vn Prasad, Jason S. Shapiro, Anita Thakur, Tatsuya Sato, Ting Liu, Rongxue Wu, Hossein Ardehali, Hsiang-Chun Chang, Konrad T Sawicki, and Chunlei Chen
- Subjects
0301 basic medicine ,Mitochondrial ROS ,Iron ,Ischemia ,Cardiomyopathy ,heart failure ,Myocardial Reperfusion Injury ,ischemia ,Mitochondrion ,Biology ,Cardiovascular System ,03 medical and health sciences ,medicine ,Animals ,Humans ,Research Articles ,chemistry.chemical_classification ,Reactive oxygen species ,Metabolism ,medicine.disease ,ischemia/reperfusion ,Electron transport chain ,Mitochondria ,Cell biology ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,chemistry ,Biochemistry ,Heart failure ,Molecular Medicine ,Cardiomyopathies ,Reactive Oxygen Species ,Research Article - Abstract
Excess cellular iron increases reactive oxygen species (ROS) production and causes cellular damage. Mitochondria are the major site of iron metabolism and ROS production; however, few studies have investigated the role of mitochondrial iron in the development of cardiac disorders, such as ischemic heart disease or cardiomyopathy (CM). We observe increased mitochondrial iron in mice after ischemia/reperfusion (I/R) and in human hearts with ischemic CM, and hypothesize that decreasing mitochondrial iron protects against I/R damage and the development of CM. Reducing mitochondrial iron genetically through cardiac‐specific overexpression of a mitochondrial iron export protein or pharmacologically using a mitochondria‐permeable iron chelator protects mice against I/R injury. Furthermore, decreasing mitochondrial iron protects the murine hearts in a model of spontaneous CM with mitochondrial iron accumulation. Reduced mitochondrial ROS that is independent of alterations in the electron transport chain's ROS producing capacity contributes to the protective effects. Overall, our findings suggest that mitochondrial iron contributes to cardiac ischemic damage, and may be a novel therapeutic target against ischemic heart disease.
- Published
- 2016
91. Visualizing the Knowledge Domain of Multimodal Discourse Analysis (2009-2019): A Bibliometric Review
- Author
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Chunlei Chen
- Subjects
business.industry ,Computer science ,Discourse analysis ,Artificial intelligence ,business ,computer.software_genre ,computer ,Natural language processing ,Domain (software engineering) - Abstract
Different from traditional discourse analysis, multimodal discourse analysis (MDA), a systematic analysis of different semiotic modes, utilizing language, images, sounds in a discourse, emphasizes the coordination of both dynamic and static semiotic resources. This study presents the status quo and development trend of the research field through an objective, systematic, and comprehensive review of relevant publications available from the Web of Science Core Collection. Analysis techniques including a descriptive statistical method and a bibliometric method are used. The study quantitatively analyzes the publications in terms of general characteristics, geographical distribution, high-cited representatives, and topic discovery and distribution to illustrate the development and trend of MDA. The research findings are as follows: (1) In the past 10 years or so, international MDA research has presented a significant growth trend, with flourishing research output, interest and diversification of presented subjects; (2) New topics are constantly emerging, with research topics mainly focusing on the development of visual grammar, gesture, digital technologies, conference presentations, metonymy and metaphor, etc.; (3) Research focuses mainly on multimodality, semiotics, conversation analysis, critical discourse analysis etc.; (4) The article also listed a series of important and highly influential literature, countries, journals and authors on MDA during different periods. It is hoped that this paper can provide a reference for the further study of MDA.
- Published
- 2020
92. Biosurfactant-facilitated biodegradation of hydrophobic organic compounds in hydraulic fracturing flowback wastewater: A dose–effect analysis
- Author
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Chuhan Dai, Chunlei Chen, Xiaomin Huang, Yanhong Li, Hanghai Zhou, Qiliang Ni, and Chunfang Zhang
- Subjects
021110 strategic, defence & security studies ,Strain (chemistry) ,biology ,Chemistry ,Pseudomonas ,0211 other engineering and technologies ,Soil Science ,02 engineering and technology ,Plant Science ,010501 environmental sciences ,Biodegradation ,Bacterial growth ,biology.organism_classification ,01 natural sciences ,Salinity ,Bioremediation ,Wastewater ,Environmental chemistry ,Critical micelle concentration ,0105 earth and related environmental sciences ,General Environmental Science - Abstract
This work investigated the effects of biosurfactant at varied dose on the bioremediation of hydraulic fracturing flowback wastewater (HFFW) and explored the associated mechanism. Initially, a biosurfactant-producing strain Pseudomonas sp. CH1 was isolated from oily sludge. The glycolipid biosurfactant produced by CH1 have a critical micelle concentration (CMC) of 80 mg/L, and showed high stability over a wide range of temperature (0–120 °C), pH (4–12), and salinity (0%–16%, w/v). Addition of sub-CMC dose of biosurfactant to HFFW greatly enhanced the microbial growth and activity, upregulated the expression levels of degradation-related genes, and effectively promoted the biodegradation of n-alkanes (reduction from 272.21 to 56.93 mg/L) and PAHs (reduction from 61.6 to 16.36 μ g/L) in 7 days. The results suggested the feasibility of applying biosurfactant with sub-CMC dose to remediate HFFW and contribute significantly to the optimization of surfactant-facilitated bioremediation strategies.
- Published
- 2020
93. The distribution characteristics of polychlorinated biphenyls (PCBs) in the surface sediments of Ross Sea and Drake Passage, Antarctica: A 192 congeners analysis
- Author
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Xibin Han, Zhaochao Deng, Bingbing Ma, Zhichao Zhang, Chunlei Chen, Dongdong Zhang, Heng Wang, and Chunfang Zhang
- Subjects
0106 biological sciences ,Geologic Sediments ,010604 marine biology & hydrobiology ,Antarctic Regions ,Biological pump ,Sediment ,010501 environmental sciences ,Aquatic Science ,Oceanography ,Polychlorinated Biphenyls ,01 natural sciences ,Pollution ,Congener ,Environmental science ,Water Pollutants, Chemical ,Distribution characteristic ,Primary productivity ,Environmental Monitoring ,0105 earth and related environmental sciences - Abstract
A total of 23 sediment samples are collected from Ross Sea and Drake Passage to investigate the distribution characteristics of polychlorinated biphenyls (PCBs) in the Antarctic marine sediments. Over 51 kinds of PCBs are detected through exhaustive searches using multiple reaction monitoring system. The results show that the concentration of individual PCB congener and total PCBs vary greatly among sampling sites, ranging from not detected to 49.75 ng g−1 and 3.77 to 246.86 ng g−1, respectively. The average PCBs level in Ross Sea is ten times higher than that in Drake Passage. Two different homologues, hexa- and tetra-CBs, give high contributions to ∑PCBs level in most samples from Ross Sea and Drake Passage, respectively. Our results support that the marine sediments might be an important sink for PCBs. Besides, the biological pump and the primary productivity might be responsible for the distribution differences of PCBs between Ross Sea and Drake Passage.
- Published
- 2020
94. mRNA-binding protein tristetraprolin is essential for cardiac response to iron deficiency by regulating mitochondrial function
- Author
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Issam Ben-Sahra, Deborah J. Stumpo, Paul T. Schumacker, Ting Liu, Hsiang-Chun Chang, Hossein Ardehali, Lucía Ramos-Alonso, Konrad T Sawicki, Xinghang Jiang, Sergi Puig, Marina Bayeva, Hidemichi Kouzu, María Teresa Martínez-Pastor, Perry J. Blackshear, Chunlei Chen, Sumeyye Yar, Jason S. Shapiro, and Tatsuya Sato
- Subjects
0301 basic medicine ,Cardiac response ,Cardiac function curve ,Iron-Sulfur Proteins ,Tristetraprolin ,Mitochondria, Heart ,Cell Line ,03 medical and health sciences ,Electron Transport Complex III ,Mice ,medicine ,Animals ,chemistry.chemical_classification ,Mice, Knockout ,Reactive oxygen species ,Multidisciplinary ,NDUFS1 ,Myocardium ,NADH Dehydrogenase ,Iron deficiency ,Iron Deficiencies ,medicine.disease ,Cell biology ,030104 developmental biology ,chemistry ,PNAS Plus ,Coenzyme Q – cytochrome c reductase ,Oxidation-Reduction ,Function (biology) - Abstract
Cells respond to iron deficiency by activating iron-regulatory proteins to increase cellular iron uptake and availability. However, it is not clear how cells adapt to conditions when cellular iron uptake does not fully match iron demand. Here, we show that the mRNA-binding protein tristetraprolin (TTP) is induced by iron deficiency and degrades mRNAs of mitochondrial Fe/S-cluster-containing proteins, specifically Ndufs1 in complex I and Uqcrfs1 in complex III, to match the decrease in Fe/S-cluster availability. In the absence of TTP, Uqcrfs1 levels are not decreased in iron deficiency, resulting in nonfunctional complex III, electron leakage, and oxidative damage. Mice with deletion of Ttp display cardiac dysfunction with iron deficiency, demonstrating that TTP is necessary for maintaining cardiac function in the setting of low cellular iron. Altogether, our results describe a pathway that is activated in iron deficiency to regulate mitochondrial function to match the availability of Fe/S clusters.
- Published
- 2018
95. Ascitic Bacterial Composition Is Associated With Clinical Outcomes in Cirrhotic Patients With Culture-Negative and Non-neutrocytic Ascites
- Author
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Lanjuan Li, Chunlei Chen, Jing Guo, Daiqiong Fang, Ding Shi, and Yanfei Chen
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0301 basic medicine ,Microbiology (medical) ,Adult ,Liver Cirrhosis ,Male ,China ,Rikenellaceae ,Firmicutes ,end-stage liver disease ,Immunology ,lcsh:QR1-502 ,Becaplermin ,Veillonellaceae ,microbiome ,Prevotellaceae ,Peritonitis ,Microbiology ,lcsh:Microbiology ,03 medical and health sciences ,Cellular and Infection Microbiology ,Vibrionaceae ,RNA, Ribosomal, 16S ,Ascitic Fluid ,Cluster Analysis ,Humans ,bacterial translocation ,Aged ,Original Research ,biology ,Bacteria ,Interleukin-7 ,Microbiota ,Lachnospiraceae ,Interleukin-17 ,Bacteroidetes ,Ascites ,Middle Aged ,biology.organism_classification ,Bacteroidales ,cytokines ,030104 developmental biology ,Infectious Diseases ,Female ,ascitic fluids - Abstract
Background: Ascites bacterial burden is associated with poor clinical outcomes in patients with end-stage liver disease. However, the impact of ascitic microbial composition on clinical course was still not clear. In this study, the ascitic microbiota composition of 100 cirrhotic patients with culture-negative and nonneutrocytic ascites were researched. Results: By characterizing the ascitic microbial composition, two distinct microbial clusters were observed, Cluster 1 (86 patients) and Cluster 2 (14 patients). Cluster 1 showed lower microbial richness than Cluster 2. At the phylum level, Cluster 1 had greater abundance of Bacteroidetes and Firmicutes, but less abundance of Proteobacteria and Actinobacteria than Cluster 2. At the family level, family Bacteroidales S24-7 group, Prevotellaceae, Lachnospiraceae, Lactobacillaceae, Rikenellaceae, and Vibrionaceae were found over-represented in Cluster 1. And family Acetobacteraceae, Erysipelotrichaceae, Rickettsiaceae, and Streptococcaceae were found enriched in Cluster 2. The levels of plasma cytokine IL-17A, IL-7, and PDGF-BB were found significantly higher in Cluster 1 than in Cluster 2. There were four OTUs closely correlated with plasma cytokines, which were OTU 140 and OTU 271 (both from Bacteroidales S24-7 group), OTU 68 (Veillonellaceae), and OTU 53 (Helicobacteraceae). Patients from Cluster 1 showed significant higher short-term mortality than patients from Cluster 2. Conclusion: Our study demonstrated that the microbial composition of culture-negative and nonneutrocytic ascites in cirrhotic patients is associated with short-term clinical outcomes. The results here offer a rational for the identification of patients with high risk, and provide references for selective use of prophylactic methods.
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- 2018
96. Electrochemical and in-situ scanning tunneling microscopy studies of bis(fluorosulfonyl)imide and bis(trifluoromethanesulfonyl)imide based ionic liquids on graphite and gold electrodes and lithium salt influence
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Jiawei Yan, Bing-Wei Mao, Chunlei Chen, and Xiaoyan Hu
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Renewable Energy, Sustainability and the Environment ,Chemistry ,Intercalation (chemistry) ,Inorganic chemistry ,Energy Engineering and Power Technology ,chemistry.chemical_element ,Electrochemistry ,Exfoliation joint ,law.invention ,chemistry.chemical_compound ,law ,Ionic liquid ,Lithium ,Graphite ,Electrical and Electronic Engineering ,Physical and Theoretical Chemistry ,Scanning tunneling microscope ,Imide - Abstract
We report electrochemical and in-situ scanning tunneling microscopy (STM) studies of surface processes on graphite and Au(111) electrodes in N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)imide (Py 13 FSI) and N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (Py 13 TFSI) ionic liquids in the absence and presence of LiTFSI salt. In both of neat ionic liquids, the intercalation of cations and exfoliation of HOPG layers occur during cathodic excursion. However, the surface decomposition of FSI anions can form an effective protection film on the surface, which suppresses the intercalation and exfoliation processes, while the surface decomposition of TFSI anions mainly causes etching of the surface, which makes the intercalation and exfoliation easier to proceed. The addition of Li salt can promote the formation of the protective film, especially in Py 13 FSI, and thus significantly suppress the intercalation and exfoliation processes. The discrepancies between these two ionic liquids are caused by the different anion interactions with graphite. Additionally, comparisons of the behaviors on HOPG and on Au(111) confirm that the surface processes are crucially dependent on the nature of the electrode. Trace amounts of oxygen and water can cause the formation of a film-like structure on Au(111), but show no apparent influence on HOPG.
- Published
- 2015
97. Fast fairness convergence through fair rate estimation in Variable-structure congestion Control Protocol
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Hairui Zhou, Huixiang Zhang, Guanzhong Dai, and Chunlei Chen
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Mathematical optimization ,Computer Networks and Communications ,Computer science ,business.industry ,Transmission Control Protocol ,Congestion window ,Throughput ,Fair queuing ,TCP congestion-avoidance algorithm ,Network congestion ,Max-min fairness ,Convergence (routing) ,Fairness measure ,business ,Queue ,Explicit Congestion Notification ,Computer network - Abstract
Traditional Transmission Control Protocol (TCP) faces significant limitations such as unclear congestion implication, low utilization in high-speed networks, unstable throughput and limited fairness. In order to overcome such limitations, numerous research works have been done in effective congestion control algorithms. Among these, Variable-structure congestion Control Protocol (VCP) leverages only the existing two explicit congestion notification bits for network congestion feedback, yet achieves high utilization, low persistent queue length, negligible packet loss rate and reasonable fairness. However, VCP converges to fairness relatively slowly due to its large multiplicative decrease parameter. To address this problem, we propose an end-host based method for fast fairness convergence, namely VCP-FFC (VCP with fast fairness convergence). In each Additive Increase and Multiplicative Decrease (AIMD) epoch, VCP-FFC estimates a fair rate in end-hosts, and adjusts the congestion window according to the fair rate to achieve fast fairness convergence. We evaluate the performance of VCP-FFC over a wide range of network scenarios using NS2. Simulation Results show that VCP-FFC not only maintains the good properties of VCP, but also significantly accelerates fairness convergence. Dynamic analysis shows that VCP-FFC is asymptotically stable and converges to a unique stationary point, i.e. the fair rate share.
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- 2015
98. An in situ STM investigation of EMITFSI ionic liquid on Au(111) in the presence of lithium salt
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Jiawei Yan, Wei-Wei Wang, Xiaoyan Hu, Bing-Wei Mao, Shuai Tang, and Chunlei Chen
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chemistry.chemical_classification ,Multidisciplinary ,Chemistry ,Inorganic chemistry ,Salt (chemistry) ,chemistry.chemical_element ,Electrolyte ,Underpotential deposition ,Decomposition ,Lithium hydroxide ,chemistry.chemical_compound ,Electrode ,Ionic liquid ,Lithium - Abstract
We report an in situ scanning tunneling microscopic study of surface morphology changes in Au(111) electrode in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMITFSI) ionic liquid containing LiTFSI salt. The surface processes can be divided into three stages: In the first stage, a reduction wave of dissolved oxygen in the ionic liquid appears at approximately 2.0 V and a network structure covers the surface afterward; in the second stage at around 1.5 V, reduction of trace water is initiated and a surface film containing lithium hydroxide is formed; in the third stage, as potential is further decreased to 0.85 V, decomposition of the EMITFSI ionic liquid occurs, which is accompanied by lithium underpotential deposition and Au–Li alloying. In this stage, the surface experiences significant morphological changes with formation of many clusters on the surface, and eventually becomes electronically less conductive. This unique surface film is understood to be the initial stage formation of a solid electrolyte interphase on gold, which may be a common feature in ionic liquids in the presence of lithium salt.
- Published
- 2015
99. Characteristics of Volatile Organic Compounds Emitted from Airport Sources and Their Effects on Ozone Production
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Mubai Chen, Shiping Li, Long Yun, Yongjiang Xu, Daiwei Chen, Chuxiong Lin, Zhicheng Qiu, Yinong You, Ming Liu, Zhenrong Luo, Liyun Zhang, Chunlei Cheng, and Mei Li
- Subjects
volatile organic compounds ,oxygenated volatile organic compounds ,airport source ,ozone formation potential ,Chemical technology ,TP1-1185 - Abstract
In recent years, commercial air transport has increased considerably. However, the compositions and source profiles of volatile organic compounds (VOCs) emitted from aircraft are still not clear. In this study, the characteristics of VOCs (including oxygenated VOCs (OVOCs)) emitted from airport sources were measured at Shenzhen Bao’an International Airport. The results showed that the compositions and proportions of VOC species showed significant differences as the aircraft operating state changed. OVOCs were the dominant species and accounted for 63.17%, 58.44%, and 51.60% of the total VOC mass concentration during the taxiing, approach, and take-off stages. Propionaldehyde and acetone were the main OVOCs, and dichloromethane and 1,2-dichloroethane were the main halohydrocarbons. Propane had the highest proportion among all alkanes, while toluene and benzene were the predominant aromatic hydrocarbons. Compared with the source profiles of VOCs from construction machinery, the proportions of halogenated hydrocarbons and alkanes emitted from aircraft were significantly higher, as were those of propionaldehyde and acetone. OVOCs were still the dominant VOC species in aircraft emissions, and their calculated ozone formation potential (OFP) was much higher than that of other VOC species at all stages of aircraft operations. Acetone, propionaldehyde, formaldehyde, acetaldehyde, and ethylene were the greatest contributors to ozone production. This study comprehensively measured the distribution characteristics of VOCs, and its results will aid in the construction of a source profile inventory of VOCs emitted from aircraft sources in real atmospheric environments.
- Published
- 2024
- Full Text
- View/download PDF
100. Performance of the Transverse Connectivity in Simply Supported Girder Bridges and Its Strengthening Strategy
- Author
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Jinfeng Wang, Chunlei Chen, Huawei Xiang, and Xinglang Fan
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Computer science ,Calibration (statistics) ,business.industry ,0211 other engineering and technologies ,020101 civil engineering ,02 engineering and technology ,Building and Construction ,Structural engineering ,0201 civil engineering ,Transverse plane ,Girder ,021105 building & construction ,Safety, Risk, Reliability and Quality ,business ,Civil and Structural Engineering - Abstract
A critical problem in evaluating the structural behavior of simply supported girder bridges is the performance of the transverse connectivity of girders. Traditional structural calibration ...
- Published
- 2017
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