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Hoang QT, Pham XH, Trinh XT, Le AV, Bui MV, Bui TT. An Efficient CNN-Based Method for Intracranial Hemorrhage Segmentation from Computerized Tomography Imaging. J Imaging 2024; 10:77. [PMID: 38667975 PMCID: PMC11051045 DOI: 10.3390/jimaging10040077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 04/28/2024] Open
Abstract
Intracranial hemorrhage (ICH) resulting from traumatic brain injury is a serious issue, often leading to death or long-term disability if not promptly diagnosed. Currently, doctors primarily use Computerized Tomography (CT) scans to detect and precisely locate a hemorrhage, typically interpreted by radiologists. However, this diagnostic process heavily relies on the expertise of medical professionals. To address potential errors, computer-aided diagnosis systems have been developed. In this study, we propose a new method that enhances the localization and segmentation of ICH lesions in CT scans by using multiple images created through different data augmentation techniques. We integrate residual connections into a U-Net-based segmentation network to improve the training efficiency. Our experiments, based on 82 CT scans from traumatic brain injury patients, validate the effectiveness of our approach, achieving an IOU score of 0.807 ± 0.03 for ICH segmentation using 10-fold cross-validation.
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Affiliation(s)
- Quoc Tuan Hoang
- Faculty of Mechanical Engineering, Hung Yen University of Technology and Education, 39Rd., Hung Yen 160000, Vietnam; (Q.T.H.); (X.T.T.)
| | - Xuan Hien Pham
- Faculty of Mechanical Engineering, University of Transport and Communications, Hanoi 100000, Vietnam;
| | - Xuan Thang Trinh
- Faculty of Mechanical Engineering, Hung Yen University of Technology and Education, 39Rd., Hung Yen 160000, Vietnam; (Q.T.H.); (X.T.T.)
| | - Anh Vu Le
- Communication and Signal Processing Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam
| | - Minh V. Bui
- Faculty of Engineering and Technology, Nguyen Tat Thanh University, 300A, Nguyen Tat Thanh, Ward 13, District 4, Ho Chi Minh City 700000, Vietnam;
| | - Trung Thanh Bui
- Faculty of Mechanical Engineering, Hung Yen University of Technology and Education, 39Rd., Hung Yen 160000, Vietnam; (Q.T.H.); (X.T.T.)
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Le AV, Větrovský T, Barucic D, Saraiva JP, Dobbler PT, Kohout P, Pospíšek M, da Rocha UN, Kléma J, Baldrian P. Improved recovery and annotation of genes in metagenomes through the prediction of fungal introns. Mol Ecol Resour 2023; 23:1800-1811. [PMID: 37561110 DOI: 10.1111/1755-0998.13852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 06/27/2023] [Accepted: 07/31/2023] [Indexed: 08/11/2023]
Abstract
Metagenomics provides a tool to assess the functional potential of environmental and host-associated microbiomes based on the analysis of environmental DNA: assembly, gene prediction and annotation. While gene prediction is straightforward for most bacterial and archaeal taxa, it has limited applicability in the majority of eukaryotic organisms, including fungi that contain introns in gene coding sequences. As a consequence, eukaryotic genes are underrepresented in metagenomics datasets and our understanding of the contribution of fungi and other eukaryotes to microbiome functioning is limited. Here, we developed a machine intelligence-based algorithm that predicts fungal introns in environmental DNA with reasonable precision and used it to improve the annotation of environmental metagenomes. Intron removal increased the number of predicted genes by up to 9.1% and improved the annotation of several others. The proportion of newly predicted genes increased with the share of eukaryotic genes in the metagenome and-within fungal taxa-increased with the number of introns per gene. Our approach provides a tool named SVMmycointron for improved metagenome annotation, especially of microbiomes with a high proportion of eukaryotes. The scripts described in the paper are made publicly available and can be readily utilized by microbiome researchers analysing metagenomics data.
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Affiliation(s)
- Anh Vu Le
- Department of Computer Science, Czech Technical University in Prague, Praha, Czech Republic
| | - Tomáš Větrovský
- Laboratory of Environmental Microbiology, Institute of Microbiology of the Czech Academy of Sciences, Praha, Czech Republic
| | - Denis Barucic
- Department of Computer Science, Czech Technical University in Prague, Praha, Czech Republic
| | - Joao Pedro Saraiva
- Department of Environmental Microbiology, UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Priscila Thiago Dobbler
- Laboratory of Environmental Microbiology, Institute of Microbiology of the Czech Academy of Sciences, Praha, Czech Republic
| | - Petr Kohout
- Laboratory of Environmental Microbiology, Institute of Microbiology of the Czech Academy of Sciences, Praha, Czech Republic
| | - Martin Pospíšek
- Department of Genetics and Microbiology, Charles University, Praha, Czech Republic
| | - Ulisses Nunes da Rocha
- Department of Environmental Microbiology, UFZ-Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Jiří Kléma
- Department of Computer Science, Czech Technical University in Prague, Praha, Czech Republic
| | - Petr Baldrian
- Laboratory of Environmental Microbiology, Institute of Microbiology of the Czech Academy of Sciences, Praha, Czech Republic
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Hruba P, Klema J, Le AV, Girmanova E, Mrazova P, Massart A, Maixnerova D, Voska L, Piredda GB, Biancone L, Puga AR, Seyahi N, Sever MS, Weekers L, Muhfeld A, Budde K, Watschinger B, Miglinas M, Zahradka I, Abramowicz M, Abramowicz D, Viklicky O. Novel transcriptomic signatures associated with premature kidney allograft failure. EBioMedicine 2023; 96:104782. [PMID: 37660534 PMCID: PMC10480056 DOI: 10.1016/j.ebiom.2023.104782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/18/2023] [Accepted: 08/18/2023] [Indexed: 09/05/2023] Open
Abstract
BACKGROUND The power to predict kidney allograft outcomes based on non-invasive assays is limited. Assessment of operational tolerance (OT) patients allows us to identify transcriptomic signatures of true non-responders for construction of predictive models. METHODS In this observational retrospective study, RNA sequencing of peripheral blood was used in a derivation cohort to identify a protective set of transcripts by comparing 15 OT patients (40% females), from the TOMOGRAM Study (NCT05124444), 14 chronic active antibody-mediated rejection (CABMR) and 23 stable graft function patients ≥15 years (STA). The selected differentially expressed transcripts between OT and CABMR were used in a validation cohort (n = 396) to predict 3-year kidney allograft loss at 3 time-points using RT-qPCR. FINDINGS Archetypal analysis and classifier performance of RNA sequencing data showed that OT is clearly distinguishable from CABMR, but similar to STA. Based on significant transcripts from the validation cohort in univariable analysis, 2 multivariable Cox models were created. A 3-transcript (ADGRG3, ATG2A, and GNLY) model from POD 7 predicted graft loss with C-statistics (C) 0.727 (95% CI, 0.638-0.820). Another 3-transcript (IGHM, CD5, GNLY) model from M3 predicted graft loss with C 0.786 (95% CI, 0.785-0.865). Combining 3-transcripts models with eGFR at POD 7 and M3 improved C-statistics to 0.860 (95% CI, 0.778-0.944) and 0.868 (95% CI, 0.790-0.944), respectively. INTERPRETATION Identification of transcripts distinguishing OT from CABMR allowed us to construct models predicting premature graft loss. Identified transcripts reflect mechanisms of injury/repair and alloimmune response when assessed at day 7 or with a loss of protective phenotype when assessed at month 3. FUNDING Supported by the Ministry of Health of the Czech Republic under grant NV19-06-00031.
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Affiliation(s)
- Petra Hruba
- Transplant Laboratory, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Jiri Klema
- Department of Computer Science, Czech Technical University, Prague, Czech Republic
| | - Anh Vu Le
- Department of Computer Science, Czech Technical University, Prague, Czech Republic
| | - Eva Girmanova
- Transplant Laboratory, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Petra Mrazova
- Transplant Laboratory, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Annick Massart
- Antwerp University Hospital and Antwerp University, Antwerp, Belgium
| | - Dita Maixnerova
- Department of Nephrology, 1st Faculty of Medicine and General Faculty Hospital, Prague, Czech Republic
| | - Ludek Voska
- Department of Clinical and Transplant Pathology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Gian Benedetto Piredda
- Department of Kidney Disease Medicine of Renal Transplantation, G.Brotzu Hospital Cagliari, Italy
| | - Luigi Biancone
- Department of Medical Sciences, University of Torino, Torino, Italy
| | - Ana Ramirez Puga
- Hospital Universitario Insular de Gran Canaria, Servicio de nefrología, Spain
| | - Nurhan Seyahi
- Istanbul University, Cerrahpasa Medical Faculty, Nephrology, Istanbul, Turkey
| | - Mehmet Sukru Sever
- Istanbul University, Istanbul School of Medicine, Internal Medicine, Nephrology, Istanbul, Turkey
| | | | - Anja Muhfeld
- Department of Nephrology, Uniklinik RWTH Aachen, Aachen, Germany
| | - Klemens Budde
- Charité - Universitätsmedizin Berlin, Medizinische Klinik mit Schwerpunkt Nephrologie und Internistische Intensivmedizin, Berlin, Germany
| | - Bruno Watschinger
- Department of Internal Medicine III, Nephrology, Medical University Vienna / AKH Wien, Vienna, Austria
| | - Marius Miglinas
- Faculty of Medicine, Nephrology Center, Vilnius University Hospital Santaros Klinikos, Vilnius University, Vilnius, Lithuania
| | - Ivan Zahradka
- Department of Nephrology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Marc Abramowicz
- Genetic Medicine and Development, Faculty of Medicine, University of Geneva, Rue Michel Servet 1, 1206 Geneva, Switzerland
| | - Daniel Abramowicz
- Antwerp University Hospital and Antwerp University, Antwerp, Belgium
| | - Ondrej Viklicky
- Transplant Laboratory, Institute for Clinical and Experimental Medicine, Prague, Czech Republic; Department of Nephrology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
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Tkadlec J, Le AV, Brajerova M, Soltesova A, Marcisin J, Drevinek P, Krutova M. Epidemiology of Methicillin-Resistant Staphylococcus aureus in Slovakia, 2020 - Emergence of an Epidemic USA300 Clone in Community and Hospitals. Microbiol Spectr 2023; 11:e0126423. [PMID: 37341582 PMCID: PMC10433824 DOI: 10.1128/spectrum.01264-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 06/01/2023] [Indexed: 06/22/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of health care-associated infections. Additionally, over the decades, the spread of community-associated (CA-MRSA) clones has become a serious problem. The aim of this study was to gain data on the current epidemiology of MRSA in Slovakia. Between January 2020 and March 2020, single-patient MRSA isolates (invasive and/or colonizing) were collected in Slovakia from hospitalized inpatients (16 hospitals) or outpatients (77 cities). Isolates were characterized via antimicrobial susceptibility testing, spa typing, SCCmec typing, the detection of mecA/mecC, genes coding for Panton-Valentine leukocidin (PVL), and the arcA gene (part of the arginine catabolic mobile element [ACME]). Out of 412 isolates, 167 and 245 originated from hospitalized patients and outpatients, respectively. Inpatients were most likely older (P < 0.001) and carried a strain exhibiting multiple resistance (P = 0.015). Isolates were frequently resistant to erythromycin (n = 320), clindamycin (n = 268), and ciprofloxacin/norfloxacin (n = 261). 55 isolates were resistant to oxacillin/cefoxitin only. By clonal structure, CC5-MRSA-II (n = 106; spa types t003, t014), CC22-MRSA-IV (n = 75; t032), and CC8-MRSA-IV (n = 65; t008) were the most frequent. We identified PVL in 72 isolates (17.48%; 17/412), with the majority belonging to CC8-MRSA-IV (n = 55; arcA+; t008, t622; the USA300 CA-MRSA clone) and CC5-MRSA-IV (n = 13; t311, t323). To the best of our knowledge, this is the first study on the epidemiology of MRSA in Slovakia. The presence of the epidemic HA-MRSA clones CC5-MRSA-II and CC22-MRSA-IV was found, as was, importantly, the emergence of the global epidemic USA300 CA-MRSA clone. The extensive spread of USA300 among inpatients and outpatients across the Slovakian regions warrants further investigation. IMPORTANCE The epidemiology of MRSA is characterized by the rise and fall of epidemic clones. Understanding the spread, as well as the evolution of successful MRSA clones, depends on the knowledge of global MRSA epidemiology. However, basic knowledge about MRSA epidemiology is still fragmented or completely missing in some parts of the world. This is the first study of MRSA epidemiology in Slovakia to identify the presence of the epidemic HA-MRSA clones CC5-MRSA-II and CC22-MRSA-IV and, importantly and unexpectedly, the emergence of the global epidemic USA300 CA-MRSA clone in the Slovakian community and hospitals. So far, USA300 has failed to spread in Europe, and this study documents an extensive spread of this epidemic clone in a European country for the first time.
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Affiliation(s)
- Jan Tkadlec
- Department of Medical Microbiology, Charles University, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic
| | - Anh Vu Le
- Department of Computer Science, Czech Technical University, Faculty of Electrical Engineering, Prague, Czech Republic
| | - Marie Brajerova
- Department of Medical Microbiology, Charles University, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic
| | - Anna Soltesova
- Department of Clinical Biochemistry, Haematology and Microbiology, Unilabs Slovensko, s.r.o., Roznava, Slovakia
| | - Jozef Marcisin
- Department of Clinical Microbiology, Unilabs Slovensko, s.r.o., Stropkov, Slovakia
| | - Pavel Drevinek
- Department of Medical Microbiology, Charles University, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic
| | - Marcela Krutova
- Department of Medical Microbiology, Charles University, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic
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Kyaw PT, Le AV, Veerajagadheswar P, Elara MR, Thu TT, Nhan NHK, Van Duc P, Vu MB. Energy-Efficient Path Planning of Reconfigurable Robots in Complex Environments. IEEE T ROBOT 2022. [DOI: 10.1109/tro.2022.3147408] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Sivanantham V, Le AV, Shi Y, Elara MR, Sheu BJ. Adaptive Floor Cleaning Strategy by Human Density Surveillance Mapping with a Reconfigurable Multi-Purpose Service Robot. Sensors (Basel) 2021; 21:2965. [PMID: 33922638 PMCID: PMC8122887 DOI: 10.3390/s21092965] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/18/2021] [Accepted: 04/22/2021] [Indexed: 11/16/2022]
Abstract
Professional cleaning and safe social distance monitoring are often considered as demanding, time-consuming, repetitive, and labor-intensive tasks with the risk of getting exposed to the virus. Safe social distance monitoring and cleaning are emerging problems solved through robotics solutions. This research aims to develop a safe social distance surveillance system on an intra-reconfigurable robot with a multi-robot cleaning system for large population environments, like office buildings, hospitals, or shopping malls. We propose an adaptive multi-robot cleaning strategy based on zig-zag-based coverage path planning that works in synergy with the human interaction heat map generated by safe social distance monitoring systems. We further validate the proposed adaptive velocity model's efficiency for the multi-robot cleaning systems regarding time consumption and energy saved. The proposed method using sigmoid-based non-linear function has shown superior performance with 14.1 percent faster and energy consumption of 11.8 percent less than conventional cleaning methods.
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Affiliation(s)
- Vinu Sivanantham
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (V.S.); (Y.S.); (M.R.E.)
| | - Anh Vu Le
- Optoelectronics Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam
| | - Yuyao Shi
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (V.S.); (Y.S.); (M.R.E.)
| | - Mohan Rajesh Elara
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (V.S.); (Y.S.); (M.R.E.)
| | - Bing J. Sheu
- Department of Electronics Engineering, Chang Gung University, Taoyuan City 33302, Taiwan;
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Samarakoon SMBP, Muthugala MAVJ, Le AV, Elara MR. Toward complete area coverage of a reconfigurable tiling robot by following obstacle shape. COMPLEX INTELL SYST 2021. [DOI: 10.1007/s40747-020-00243-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AbstractComplete area coverage is a crucial factor for a floor cleaning robot. Self-reconfigurable tiling robots have been introduced over robots with a fixed shape for floor cleaning since they improve the area coverage by the flexibility of shape-shifting in cluttered environments. The existing coverage methods of reconfigurable tiling robots follow the tiling theory to cope with the area coverage problem. However, these methods merely consider a limited set of predefined shapes for the reconfiguration of a robot. The consideration of a limited set of predefined shapes for the reconfiguration impedes the ability of coverage to a certain extent in typical floor environments. Therefore, this paper proposes a novel method to improve area coverage of a tiling robot by reconfiguring according to the shape of obstacles. To this end, the required hinge angles for reconfiguring per the shape of an obstacle are determined by a genetic algorithm. The proposed method considers an optimized shape for reconfiguration in lieu of a limited set of predefined shapes. The coverage improvement of the proposed concept has been compared against the existing coverage methods of tiling robots to validate the performance. According to the experimental results, the proposed method surpasses the existing coverage methods of tiling robots from the perspective of area coverage, and the improvement is significant and noteworthy.
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Shi Y, Elara MR, Le AV, Prabakaran V, Wood KL. Path Tracking Control of Self-Reconfigurable Robot hTetro With Four Differential Drive Units. IEEE Robot Autom Lett 2020. [DOI: 10.1109/lra.2020.2983683] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Muthugala MAVJ, Le AV, Cruz ES, Rajesh Elara M, Veerajagadheswar P, Kumar M. A Self-Organizing Fuzzy Logic Classifier for Benchmarking Robot-Aided Blasting of Ship Hulls. Sensors (Basel) 2020; 20:E3215. [PMID: 32517069 PMCID: PMC7308935 DOI: 10.3390/s20113215] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 05/29/2020] [Accepted: 06/02/2020] [Indexed: 11/23/2022]
Abstract
Regular dry dock maintenance work on ship hulls is essential for maintaining the efficiency and sustainability of the shipping industry. Hydro blasting is one of the major processes of dry dock maintenance work, where human labor is extensively used. The conventional methods of maintenance work suffer from many shortcomings, and hence robotized solutions have been developed. This paper proposes a novel robotic system that can synthesize a benchmarking map for a previously blasted ship hull. A Self-Organizing Fuzzy logic (SOF) classifier has been developed to benchmark the blasting quality of a ship hull similar to blasting quality categorization done by human experts. Hornbill, a multipurpose inspection and maintenance robot intended for hydro blasting, benchmarking, and painting, has been developed by integrating the proposed SOF classifier. Moreover, an integrated system solution has been developed to improve dry dock maintenance of ship hulls. The proposed SOF classifier can achieve a mean accuracy of 0.9942 with an execution time of 8.42 μ s. Realtime experimenting with the proposed robotic system has been conducted on a ship hull. This experiment confirms the ability of the proposed robotic system in synthesizing a benchmarking map that reveals the benchmarking quality of different areas of a previously blasted ship hull. This sort of a benchmarking map would be useful for ensuring the blasting quality as well as performing efficient spot wise reblasting before the painting. Therefore, the proposed robotic system could be utilized for improving the efficiency and quality of hydro blasting work on the ship hull maintenance industry.
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Affiliation(s)
- M. A. Viraj J. Muthugala
- Engineering Product Development Pillar, Singapore University of Technology and Design, 8 Somapah Rd, Singapore 487372, Singapore; (E.S.C.); (M.R.E.); (P.V.)
| | - Anh Vu Le
- Optoelectronics Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam;
| | - Eduardo Sanchez Cruz
- Engineering Product Development Pillar, Singapore University of Technology and Design, 8 Somapah Rd, Singapore 487372, Singapore; (E.S.C.); (M.R.E.); (P.V.)
| | - Mohan Rajesh Elara
- Engineering Product Development Pillar, Singapore University of Technology and Design, 8 Somapah Rd, Singapore 487372, Singapore; (E.S.C.); (M.R.E.); (P.V.)
| | - Prabakaran Veerajagadheswar
- Engineering Product Development Pillar, Singapore University of Technology and Design, 8 Somapah Rd, Singapore 487372, Singapore; (E.S.C.); (M.R.E.); (P.V.)
| | - Madhu Kumar
- Brightsun Marine Pte Ltd, 9 Tuas Ave 8, Singapore 639224, Singapore;
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Le AV, Parween R, Elara Mohan R, Nhan NHK, Enjikalayil Abdulkader R. Optimization Complete Area Coverage by Reconfigurable hTrihex Tiling Robot. Sensors (Basel) 2020; 20:s20113170. [PMID: 32503188 PMCID: PMC7308827 DOI: 10.3390/s20113170] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/21/2020] [Accepted: 05/22/2020] [Indexed: 11/16/2022]
Abstract
Completed area coverage planning (CACP) plays an essential role in various fields of robotics, such as area exploration, search, rescue, security, cleaning, and maintenance. Tiling robots with the ability to change their shape is a feasible solution to enhance the ability to cover predefined map areas with flexible sizes and to access the narrow space constraints. By dividing the map into sub-areas with the same size as the changeable robot shapes, the robot can plan the optimal movement to predetermined locations, transform its morphologies to cover the specific area, and ensure that the map is completely covered. The optimal navigation planning problem, including the least changing shape, shortest travel distance, and the lowest travel time while ensuring complete coverage of the map area, are solved in this paper. To this end, we propose the CACP framework for a tiling robot called hTrihex with three honeycomb shape modules. The robot can shift its shape into three different morphologies ensuring coverage of the map with a predetermined size. However, the ability to change shape also raises the complexity issues of the moving mechanisms. Therefore, the process of optimizing trajectories of the complete coverage is modeled according to the Traveling Salesman Problem (TSP) problem and solved by evolutionary approaches Genetic Algorithm (GA) and Ant Colony Optimization (ACO). Hence, the costweight to clear a pair of waypoints in the TSP is defined as the required energy shift the robot between the two locations. This energy corresponds to the three operating processes of the hTrihex robot: transformation, translation, and orientation correction. The CACP framework is verified both in the simulation environment and in the real environment. From the experimental results, proposed CACP capable of generating the Pareto-optimal outcome that navigates the robot from the goal to destination in various workspaces, and the algorithm could be adopted to other tiling robot platforms with multiple configurations.
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Affiliation(s)
- Anh Vu Le
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (A.V.L.); (R.P.); (R.E.M.); (R.E.A.)
- Optoelectronics Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam
| | - Rizuwana Parween
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (A.V.L.); (R.P.); (R.E.M.); (R.E.A.)
| | - Rajesh Elara Mohan
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (A.V.L.); (R.P.); (R.E.M.); (R.E.A.)
| | - Nguyen Huu Khanh Nhan
- Optoelectronics Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam
- Correspondence:
| | - Raihan Enjikalayil Abdulkader
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (A.V.L.); (R.P.); (R.E.M.); (R.E.A.)
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Affiliation(s)
- Maurizio Trevisan
- Maurizio Trevisan and Linh Cu Le are with the College of Health Sciences, VinUniversity, Hanoi, Vietnam. Anh Vu Le is with the Vietnam Public Health Association, Hanoi, Vietnam
| | - Linh Cu Le
- Maurizio Trevisan and Linh Cu Le are with the College of Health Sciences, VinUniversity, Hanoi, Vietnam. Anh Vu Le is with the Vietnam Public Health Association, Hanoi, Vietnam
| | - Anh Vu Le
- Maurizio Trevisan and Linh Cu Le are with the College of Health Sciences, VinUniversity, Hanoi, Vietnam. Anh Vu Le is with the Vietnam Public Health Association, Hanoi, Vietnam
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Abstract
Coverage path planning technique is an essential ingredient in every floor cleaning robotic systems. Even though numerous approaches demonstrate the benefits of conventional coverage motion planning techniques, they are mostly limited to fixed morphological platforms. In this article, we put forward a novel motion planning technique for a Tetris-inspired reconfigurable floor cleaning robot named “hTetro” that can reconfigure its morphology to any of the seven one-sided Tetris pieces. The proposed motion planning technique adapts polyomino tiling theory to tile a defined space, generates reference coordinates, and produces a navigation path to traverse on the generated tile-set with an objective of maximizing the area coverage. We have summarized all these aspects and concluded with experiments in a simulated environment that benchmarks the proposed technique with conventional approaches. The results show that the proposed motion planning technique achieves significantly higher performance in terms of area recovered than the traditional methods.
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Affiliation(s)
- Prabakaran Veerajagadheswar
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore, Singapore
| | - Ku Ping-Cheng
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore, Singapore
| | - Mohan Rajesh Elara
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore, Singapore
| | - Anh Vu Le
- Optoelectronics Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam
| | - Masami Iwase
- Department of Robotics and Mechatronics, Graduate School of Science and Technology for Future Life, Tokyo Denki University, Tokyo, Japan
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Yin J, Apuroop KGS, Tamilselvam YK, Mohan RE, Ramalingam B, Le AV. Table Cleaning Task by Human Support Robot Using Deep Learning Technique. Sensors (Basel) 2020; 20:s20061698. [PMID: 32197483 PMCID: PMC7146232 DOI: 10.3390/s20061698] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 03/11/2020] [Accepted: 03/13/2020] [Indexed: 11/16/2022]
Abstract
This work presents a table cleaning and inspection method using a Human Support Robot (HSR) which can operate in a typical food court setting. The HSR is able to perform a cleanliness inspection and also clean the food litter on the table by implementing a deep learning technique and planner framework. A lightweight Deep Convolutional Neural Network (DCNN) has been proposed to recognize the food litter on top of the table. In addition, the planner framework was proposed to HSR for accomplishing the table cleaning task which generates the cleaning path according to the detection of food litter and then the cleaning action is carried out. The effectiveness of the food litter detection module is verified with the cleanliness inspection task using Toyota HSR, and its detection results are verified with standard quality metrics. The experimental results show that the food litter detection module achieves an average of 96% detection accuracy, which is more suitable for deploying the HSR robots for performing the cleanliness inspection and also helps to select the different cleaning modes. Further, the planner part has been tested through the table cleaning tasks. The experimental results show that the planner generated the cleaning path in real time and its generated path is optimal which reduces the cleaning time by grouping based cleaning action for removing the food litters from the table.
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Affiliation(s)
- Jia Yin
- Engineering Product Development Pillar, Singapore University of Technology and Design (SUTD), Singapore 487372, Singapore; (J.Y.); (K.G.S.A.); (R.E.M.)
| | - Koppaka Ganesh Sai Apuroop
- Engineering Product Development Pillar, Singapore University of Technology and Design (SUTD), Singapore 487372, Singapore; (J.Y.); (K.G.S.A.); (R.E.M.)
| | | | - Rajesh Elara Mohan
- Engineering Product Development Pillar, Singapore University of Technology and Design (SUTD), Singapore 487372, Singapore; (J.Y.); (K.G.S.A.); (R.E.M.)
| | - Balakrishnan Ramalingam
- Engineering Product Development Pillar, Singapore University of Technology and Design (SUTD), Singapore 487372, Singapore; (J.Y.); (K.G.S.A.); (R.E.M.)
- Correspondence: (B.R.); (A.V.L.)
| | - Anh Vu Le
- Optoelectronics Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam
- Correspondence: (B.R.); (A.V.L.)
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Le AV, Nhan NHK, Mohan RE. Evolutionary Algorithm-Based Complete Coverage Path Planning for Tetriamond Tiling Robots. Sensors (Basel) 2020; 20:s20020445. [PMID: 31941127 PMCID: PMC7013451 DOI: 10.3390/s20020445] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/23/2019] [Accepted: 01/08/2020] [Indexed: 11/25/2022]
Abstract
Tiling robots with fixed morphology face major challenges in terms of covering the cleaning area and generating the optimal trajectory during navigation. Developing a self-reconfigurable autonomous robot is a probable solution to these issues, as it adapts various forms and accesses narrow spaces during navigation. The total navigation energy includes the energy expenditure during locomotion and the shape-shifting of the platform. Thus, during motion planning, the optimal navigation sequence of a self-reconfigurable robot must include the components of the navigation energy and the area coverage. This paper addresses the framework to generate an optimal navigation path for reconfigurable cleaning robots made of tetriamonds. During formulation, the cleaning environment is filled with various tiling patterns of the tetriamond-based robot, and each tiling pattern is addressed by a waypoint. The objective is to minimize the amount of shape-shifting needed to fill the workspace. The energy cost function is formulated based on the travel distance between waypoints, which considers the platform locomotion inside the workspace. The objective function is optimized based on evolutionary algorithms such as the genetic algorithm (GA) and ant colony optimization (ACO) of the traveling salesman problem (TSP) and estimates the shortest path that connects all waypoints. The proposed path planning technique can be extended to other polyamond-based reconfigurable robots.
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Affiliation(s)
- Anh Vu Le
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (A.V.L.); (R.E.M.)
- Optoelectronics Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam
| | - Nguyen Huu Khanh Nhan
- Optoelectronics Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam
- Correspondence:
| | - Rajesh Elara Mohan
- ROAR Lab, Engineering Product Development, Singapore University of Technology and Design, Singapore 487372, Singapore; (A.V.L.); (R.E.M.)
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Azari M, Le AV, Lübken M, Denecke M. Model-based analysis of microbial consortia and microbial products in an anammox biofilm reactor. Water Sci Technol 2018; 77:1951-1959. [PMID: 29676752 DOI: 10.2166/wst.2018.081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A mathematical model for a granular biofilm reactor for leachate treatment was validated by long-term measured data to investigate the mechanisms and drivers influencing biological nitrogen removal and microbial consortia dynamics. The proposed model, based on Activated Sludge Model (ASM1), included anaerobic ammonium oxidation (anammox), nitrifying and heterotrophic denitrifying bacteria which can attach and grow on granular activated carbon (GAC) particles. Two kinetic descriptions for the model were proposed: with and without soluble microbial products (SMP) and extracellular polymeric substance (EPS). The model accuracy was checked using recorded total inorganic nitrogen concentrations in the effluent and estimated relative abundance of active bacteria using quantitative fluorescence in-situ hybridization (qFISH). Results suggested that the model with EPS kinetics fits better for the relative abundance of anammox bacteria and nitrifying bacteria compared to the model without EPS. The model with EPS and SMP confirms that the growth and existence of heterotrophs in anammox biofilm systems slightly increased due to including the kinetics of SMP production in the model. During the one-year simulation period, the fractions of autotrophs and EPS in the biomass were almost stable but the fraction of heterotrophs decreased which is correlated with the reduction in nitrogen surface loading on the biofilm.
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Affiliation(s)
- M Azari
- Department of Urban Water- and Waste Management, University of Duisburg-Essen, Universitätsstraße 15, 45141 Essen, Germany E-mail: ; Contributed equally to this work
| | - A V Le
- Department of Urban Water- and Waste Management, University of Duisburg-Essen, Universitätsstraße 15, 45141 Essen, Germany E-mail: ; Contributed equally to this work
| | - M Lübken
- Institute of Urban Water Management and Environmental Engineering, Ruhr-Universität Bochum, Universitätsstraβe 150, 44801 Bochum, Germany
| | - M Denecke
- Department of Urban Water- and Waste Management, University of Duisburg-Essen, Universitätsstraße 15, 45141 Essen, Germany E-mail:
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Guo Q, Lalji R, Le AV, Judge RB, Bailey D, Thomson W, Escobar K. Survival rates and complication types for single implants provided at the Melbourne Dental School. Aust Dent J 2016; 60:353-61. [PMID: 25348471 DOI: 10.1111/adj.12248] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/22/2014] [Indexed: 12/01/2022]
Abstract
BACKGROUND Single implants and implant-supported single crowns (ISSCs) have become popular treatment modalities for single tooth replacement. Studies have identified high implant survival rates, but also many complications. The aim of this five-year retrospective study was to assess the survival rates, complication types and occurrences for single implants and ISSCs at the Melbourne Dental School (MDS) in Victoria, Australia. METHODS A search of the Royal Dental Hospital of Melbourne (RDHM) database was conducted for data on all implant treatment and reported complications during the period between 1 January 2005 and 31 December 2009. Complications were categorized into surgical, biological and restorative types. RESULTS A total of 622 implant fixtures and 444 ISSCs were inserted into 406 patients. Seventeen implants failed during the mean follow-up time of 2.18 years, yielding a 2.7% failure rate and an estimated one- and five-year survival rate of 98.8% and 93.9%, respectively. The cumulative surgical, biological and restorative complication incidences were 11.9%, 17.6% and 14.1%, respectively. CONCLUSIONS This study confirmed that single tooth replacement using implant therapy within a teaching environment had a high survival rate. However, complications frequently occurred. This article only provides a descriptive analysis. Correlation analysis between variables would provide greater insight into the causes of complications.
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Affiliation(s)
- Q Guo
- Melbourne Dental School, The University of Melbourne, Victoria
| | - R Lalji
- Melbourne Dental School, The University of Melbourne, Victoria
| | - A V Le
- Melbourne Dental School, The University of Melbourne, Victoria
| | - R B Judge
- Melbourne Dental School, The University of Melbourne, Victoria
| | - D Bailey
- Melbourne Dental School, The University of Melbourne, Victoria
| | - W Thomson
- Melbourne Dental School, The University of Melbourne, Victoria
| | - K Escobar
- Melbourne Dental School, The University of Melbourne, Victoria
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Le AV, Jung SW, Won CS. Directional joint bilateral filter for depth images. Sensors (Basel) 2014; 14:11362-78. [PMID: 24971470 PMCID: PMC4168506 DOI: 10.3390/s140711362] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Revised: 06/23/2014] [Accepted: 06/23/2014] [Indexed: 11/20/2022]
Abstract
Depth maps taken by the low cost Kinect sensor are often noisy and incomplete. Thus, post-processing for obtaining reliable depth maps is necessary for advanced image and video applications such as object recognition and multi-view rendering. In this paper, we propose adaptive directional filters that fill the holes and suppress the noise in depth maps. Specifically, novel filters whose window shapes are adaptively adjusted based on the edge direction of the color image are presented. Experimental results show that our method yields higher quality filtered depth maps than other existing methods, especially at the edge boundaries.
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Affiliation(s)
- Anh Vu Le
- Department of Electronics and Electrical Engineering, Dongguk University-Seoul, 30 Pildong-ro 1-gil, Jung-gu, Seoul 100-715, Korea.
| | - Seung-Won Jung
- Department of Multimedia Engineering, Dongguk University-Seoul, 30 Pildong-ro 1-gil, Jung-gu, Seoul 100-715, Korea.
| | - Chee Sun Won
- Department of Electronics and Electrical Engineering, Dongguk University-Seoul, 30 Pildong-ro 1-gil, Jung-gu, Seoul 100-715, Korea.
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Abstract
The Chi Linh Health and Demographic Surveillance System (CHILILAB HDSS) is the only health and demographic surveillance system (HDSS) in an urbanizing area of the Chi Linh district of Hai Duong, a northern province of Vietnam. It is one of the few field laboratories in the world that links operational research and health interventions with field training. The CHILILAB HDSS provides longitudinal data on demographic and health indicators for the community of Chi Linh. In 2012, when the CHILILAB HDSS included 57,561 people from 17 993 households in 3 towns and 4 communes, it used structured questionnaires to collect information on population changes (birth, death, migration, marriage, and pregnancy) in the community. As of December 2012, 5 rounds of a baseline survey and 17 periodic update surveys or re-enumeration surveys had been conducted. In addition, several specialized public-health research projects, focused particularly on adolescent health, have been implemented by the CHILILAB HDSS. The information that the CHILILAB HDSS has gathered provides a picture of the health status of the population and socio-economic situation in Chi Linh district. The contact person for data sharing is the director of the CHILILAB (E-mail: thb@hsph.edu.vn).
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Nguyen HT, Dunne MP, Le AV. Multiple types of child maltreatment and adolescent mental health in Viet Nam. Bull World Health Organ 2009; 88:22-30. [PMID: 20428350 DOI: 10.2471/blt.08.060061] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2008] [Revised: 02/06/2009] [Accepted: 04/16/2009] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To examine the prevalence of multiple types of maltreatment (MTM), potentially confounding factors and associations with depression, anxiety and self-esteem among adolescents in Viet Nam. METHODS In 2006 we conducted a cross-sectional survey of 2591 students (aged 12-18 years; 52.1% female) from randomly-selected classes in eight secondary schools in urban (Hanoi) and rural (Hai Duong) areas of northern Viet Nam (response rate, 94.7%). Sequential multiple regression analyses were performed to estimate the relative influence of individual, family and social characteristics and of eight types of maltreatment, including physical, emotional and sexual abuse and physical or emotional neglect, on adolescent mental health. FINDINGS Females reported more neglect and emotional abuse, whereas males reported more physical abuse, but no statistically significant difference was found between genders in the prevalence of sexual abuse. Adolescents were classified as having nil (32.6%), one (25.9%), two (20.7%), three (14.5%) or all four (6.3%) maltreatment types. Linear bivariate associations between MTM and depression, anxiety and low self-esteem were observed. After controlling for demographic and family factors, MTM showed significant independent effects. The proportions of the variance explained by the models ranged from 21% to 28%. CONCLUSION The combined influence of adverse individual and family background factors and of child maltreatment upon mental health in adolescents in Viet Nam is consistent with research in non-Asian countries. Emotional abuse was strongly associated with each health indicator. In Asian communities where child abuse is often construed as severe physical violence, it is important to emphasize the equally pernicious effects of emotional maltreatment.
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Affiliation(s)
- A V Le
- University of South Florida College of Medicine, Tampa, USA
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Green GA, Carey RN, Westgard JO, Carten T, Shablesky L, Achord D, Page E, Le AV. Quality control for qualitative assays: quantitative QC procedure designed to assure analytical quality required for an ELISA of hepatitis B surface antigen. Clin Chem 1997; 43:1618-21. [PMID: 9299942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
An assay for hepatitis B surface antigen (HBsAg) should reliably detect 0.2 microgram/L, the lowest reported concentration in an asymptomatic blood donor. The difference between this concentration and the assay cutoff defines the analytical quality requirement in a total error format. The design of a statistical QC procedure is critically dependent on the precision of the assay. The precision of a developmental ELISA of HBsAg under study ranged from 17.5% to 9.6% for controls containing 0.07 to 1.50 micrograms/L, respectively. Use of one positive control with the 1(3s), QC rule provided an 85% chance of detecting a critical loss of assay sensitivity; use of two positive controls increased the chance of detecting critical loss of assay sensitivity to nearly 100%. These rules are based on the precision of this developmental assay, and must be developed individually for other assays. The development of the proposed QC procedures illustrates how quantitative QC can be provided for qualitative assays.
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Affiliation(s)
- G A Green
- Ortho Diagnostic Systems, Raritan, NJ 08869, USA.
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Abstract
The asialoglycoprotein receptor, the hepatic binding lectin for galactose-terminated glycoproteins, has been isolated and characterized from human, rabbit and rat liver. Several recent studies have shown the existence of the same receptor in murine liver. However, the biochemical structure of the receptor in murine liver has not been resolved. In this paper, we describe the identification and purification of the receptor for asialoglycoproteins from murine liver. The purified receptor has three polypeptides with apparent molecular weights of 42,000, 45,000 and 51,000, respectively, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Furthermore, our studies suggest that the receptor from murine liver is very similar to its counterpart in rat liver, although some potential interesting differences have also been observed. Initial studies indicate that this receptor is well conserved in different mouse strains.
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Affiliation(s)
- W Hong
- Department of Biological Sciences, State University of New York at Buffalo 14260
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Le AV, Doyle D. N-Linked oligosaccharides of the H-2Dk histocompatibility protein heavy chain influence its transport and cellular distribution. Biochemistry 1985; 24:6238-45. [PMID: 4084516 DOI: 10.1021/bi00343a030] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The H-2K and H-2D proteins encoded by the K and D region of the major histocompatibility complex of the mouse were isolated by immunoprecipitation with specific antisera and resolved by two-dimensional gel electrophoresis. Of these two polypeptides, the H-2Dk glycoproteins isolated from macrophages of C3H/HeHa mice exhibit distinct cell surface and cytoplasmic forms although they share a strong degree of homology in the polypeptide backbone. Structurally they differ in their oligosaccharide structures. The structure of the oligosaccharides on the intracellular forms is of the high mannose type while the same structures on the cell surface forms are of the complex type. In the absence of all three oligosaccharide side chains, the unglycosylated polypeptides are expressed on the cell surface. In contrast, polypeptides containing one, two, or all three oligosaccharide side chains of the high mannose type are not transported to the cell surface. Cell surface expression of these glycoproteins requires processing of the oligosaccharide side chains from the high mannose form to the complex type. However, not all oligosaccharide antennae have to be terminally modified since H-2Dk glycoproteins synthesized in the presence of oligosaccharide-processing enzyme inhibitors such as swainsonine or monensin are also transported to the cell surface. H-2Dk glycoproteins containing oligosaccharide structures of the complex type but lacking terminal sialic acids are found on the cell surface, suggesting that sialylation is not required for transport. These results indicate that the oligosaccharide structures of the H-2Dk glycoproteins act to influence their cellular distribution.
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