van luong nguyen - Academia.edu (original) (raw)
Papers by van luong nguyen
Journal of Imaging
Compared to single source systems, stereo X-ray CT systems allow acquiring projection data within... more Compared to single source systems, stereo X-ray CT systems allow acquiring projection data within a reduced amount of time, for an extended field-of-view, or for dual X-ray energies. To exploit the benefit of a dual X-ray system, its acquisition geometry needs to be calibrated. Unfortunately, in modular stereo X-ray CT setups, geometry misalignment occurs each time the setup is changed, which calls for an efficient calibration procedure. Although many studies have been dealing with geometry calibration of an X-ray CT system, little research targets the calibration of a dual cone-beam X-ray CT system. In this work, we present a phantom-based calibration procedure to accurately estimate the geometry of a stereo cone-beam X-ray CT system. With simulated as well as real experiments, it is shown that the calibration procedure can be used to accurately estimate the geometry of a modular stereo X-ray CT system thereby reducing the misalignment artifacts in the reconstruction volumes.
Journal of Electronic Materials, 2015
Embedded Multi-Core Systems, 2010
2008 Ninth International Conference on Parallel and Distributed Computing, Applications and Technologies, 2008
Journal of Electronic Materials, 2014
IEEE 54th Vehicular Technology Conference. VTC Fall 2001. Proceedings (Cat. No.01CH37211), 2001
In this paper, frequency and time interleaving algorithms used for soft decision Viterbi decoding... more In this paper, frequency and time interleaving algorithms used for soft decision Viterbi decoding for OFDM systems, performed on frequency-selective and time-selective channels respectively, are investigated. To achieve optimal performance in terms of the bit error rate (BER), the size of the interleavers must be specified depending on the properties of the channel and the characteristics of the code. Under
ABSTRACT This paper investigates the performance of Vertical Bell Laboratories Layered Space Time... more ABSTRACT This paper investigates the performance of Vertical Bell Laboratories Layered Space Time (V-BLAST) architecture for multi input multi output orthogonal frequency division multiple access (MIMO-OFDMA) system. VBLAST is a successive cancellation method applied to the receiver to obtain the highest SNR. Performance of MIMO systems in realistic radio environments greatly depends on the spatial correlation due to the presence of scatterers in the multipath propagation environments.The number of users using in the system are also analyzed. It is assumed that all antennas have same radiation pattern and the spatial correlation is independent on the position of an antenna in the array. Our results are simulated on Monte Carlo and One Ring channel model for 2x2 MIMO OFDMA system. From the results, we can see that VBLAST-ZF show the best SER performance in one ring channel model with long term evolution (LTE) standard.
Planta Medica, 2010
Two new compounds, an isoflavone (1, 6-methoxybarbigerone) and a bipterocarpan (2, pachylobin) we... more Two new compounds, an isoflavone (1, 6-methoxybarbigerone) and a bipterocarpan (2, pachylobin) were isolated from the grains of Millettia pachyloba (Leguminosae), together with seven known compounds, 5-methoxybarbigerone (3), calopogoniumisoflavone B (4), durmillone (5), jamaicin (6), ichthynone (7), (-)-pisatin (8) and (-)-rotenone (9). The structures were established from spectroscopic analyses, including mass spectrometry and 2D-NMR. Absolute configuration of 2 was proposed based on that of the known compound (-)-pisatine (8). Compounds 1 and 2 exhibited cytotoxicity against KB cells with IC(50) values of 2.0 and 17.6 µM, respectively.
Microbial Cell Factories, 2011
Background Disulfide bonds are one of the most common post-translational modifications found in p... more Background Disulfide bonds are one of the most common post-translational modifications found in proteins. The production of proteins that contain native disulfide bonds is challenging, especially on a large scale. Either the protein needs to be targeted to the endoplasmic reticulum in eukaryotes or to the prokaryotic periplasm. These compartments that are specialised for disulfide bond formation have an active catalyst for their formation, along with catalysts for isomerization to the native state. We have recently shown that it is possible to produce large amounts of prokaryotic disulfide bond containing proteins in the cytoplasm of wild-type bacteria such as E. coli by the introduction of catalysts for both of these processes. Results Here we show that the introduction of Erv1p, a sulfhydryl oxidase and a disulfide isomerase allows the efficient formation of natively folded eukaryotic proteins with multiple disulfide bonds in the cytoplasm of E. coli. The production of disulfide b...
Journal of Natural Products, 2012
Journal of Chromatography B, 2011
International Journal of Behavioral Nutrition and Physical Activity, 2011
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2000
Hybrid nanocomposites based on crystalline nanoparticles dispersed in polymer matrix have been wi... more Hybrid nanocomposites based on crystalline nanoparticles dispersed in polymer matrix have been widely studied in the past few years because of the ability of these materials to combine the properties of organic polymer and inorganic nanoparticles. The aim of this work is to tune the mechanical properties of a piezoelectric polymer by adding nanoparticles to the matrix. In this paper, alumina nanoparticles were dispersed in the copolymer P(VDF-TrFE), which exhibits high piezoelectric coefficient after polarization under high electric field without needing stretching during the polarization process. Transmission electron microscopy and scanning electron microscopy demonstrate the high rate of welldispersed nanoparticles with 10% of alumina nanoparticles added to the matrix. Piezoelectric measurements indicate that P(VDF-TrFE) may be filled by up to 10 wt% of alumina while retaining its high piezoelectric properties and increasing its elastic constant by more than 20%, measured by Brillouin spectroscopy. This work opens a wide range of applications using nanoparticles with nonlinear optical, pyroelectric, magnetic, or ferroelectric properties.
BMC Health Services Research, 2012
Addiction, 2008
To provide an overall picture of drug abuse in Vietnam, its prevalence, correlates and patterns. ... more To provide an overall picture of drug abuse in Vietnam, its prevalence, correlates and patterns. Studies addressing the drug abuse problem in Vietnam are reviewed. Attention is paid to studies conducted from 1993 onwards. The reviewed studies were collected from both refereed and non-refereed sources. Drug abuse is rising sharply in Vietnam: almost threefold over the past 10 years. From a predominantly rural-mountainous phenomenon, illicit drug abuse spread rapidly to urban areas. Meanwhile, the average age of drug users has declined and more women have been engaging in drug consumption. At the same time, heroin has replaced opium as the most preferred drug in the country's illicit drug market, especially among young users in urban areas. At the national level, the second main route of drug administration, injecting, has exceeded smoking and taken precedence in the…
Six field foot-and-mouth disease viruses (FMDVs), including four serotype O and two serotype Asia... more Six field foot-and-mouth disease viruses (FMDVs), including four serotype O and two serotype Asia 1 strains, were collected from endemic outbreaks in 2005, 2006, and 2007 from four different provinces in Vietnam. The viruses were isolated and genetically characterized for their complete genomic sequences. The genetic analysis based on the complete genomic coding sequences revealed that the four serotype O FMDVs were related to each other, sharing 95.2% nucleotide (nt) identity and 97.5-97.6% amino acid (aa) identity. Genetic analysis and a phylogenetic tree, based on the VP1 gene of FMDV, showed that the four present Vietnamese serotype O strains have a high level of identity with other serotype O representatives of the Mya-98 lineage of the Southeast Asian (SEA) topotype. The four viruses were all clustered into the Mya-98 lineage of the SEA topotype, sharing 92.3-95.6% nt and 93.4-96.7% aa identity. This finding of the Mya-98 lineage was different from previous reports that the Vietnamese serotype O strains belonged to the Cam-94 lineage of the SEA topotype and two other topotypes, Middle East-South Asia (ME-SA) and Cathay. For the two serotype Asia 1 FMDVs, the genetic analysis based on the complete genomic coding sequences as well as on the VP1 gene revealed that they belonged to two genogroups, IV and V. Of note, the As1/VN/QT03/2007 strain of genogroup V, isolated in 2007, was very closely related to the pandemic Asia 1 strain which caused FMD outbreaks in China (Asia1/WHN/CHA/06, FJ906802) and Mongolia (Asia1/MOG/05, EF614458) in 2005, sharing 99.0-99.3% nt and 99.5-100% aa identity. In contrast, the second strain As1/VN/LC04/2005 of genogroup IV, isolated in 2005, was closely related to all referenced Vietnamese serotype Asia 1 strains found in the GenBank databases, sharing 86.4-100% nt and 90.9-100% aa identity with each. This study is the first description of the full-length genomic sequence of Vietnamese FMDV serotypes O and Asia 1 and may provide the evidence of the concurrent circulation of different serotypes and subtypes of FMDV in recent years in Vietnam.
Journal of Imaging
Compared to single source systems, stereo X-ray CT systems allow acquiring projection data within... more Compared to single source systems, stereo X-ray CT systems allow acquiring projection data within a reduced amount of time, for an extended field-of-view, or for dual X-ray energies. To exploit the benefit of a dual X-ray system, its acquisition geometry needs to be calibrated. Unfortunately, in modular stereo X-ray CT setups, geometry misalignment occurs each time the setup is changed, which calls for an efficient calibration procedure. Although many studies have been dealing with geometry calibration of an X-ray CT system, little research targets the calibration of a dual cone-beam X-ray CT system. In this work, we present a phantom-based calibration procedure to accurately estimate the geometry of a stereo cone-beam X-ray CT system. With simulated as well as real experiments, it is shown that the calibration procedure can be used to accurately estimate the geometry of a modular stereo X-ray CT system thereby reducing the misalignment artifacts in the reconstruction volumes.
Journal of Electronic Materials, 2015
Embedded Multi-Core Systems, 2010
2008 Ninth International Conference on Parallel and Distributed Computing, Applications and Technologies, 2008
Journal of Electronic Materials, 2014
IEEE 54th Vehicular Technology Conference. VTC Fall 2001. Proceedings (Cat. No.01CH37211), 2001
In this paper, frequency and time interleaving algorithms used for soft decision Viterbi decoding... more In this paper, frequency and time interleaving algorithms used for soft decision Viterbi decoding for OFDM systems, performed on frequency-selective and time-selective channels respectively, are investigated. To achieve optimal performance in terms of the bit error rate (BER), the size of the interleavers must be specified depending on the properties of the channel and the characteristics of the code. Under
ABSTRACT This paper investigates the performance of Vertical Bell Laboratories Layered Space Time... more ABSTRACT This paper investigates the performance of Vertical Bell Laboratories Layered Space Time (V-BLAST) architecture for multi input multi output orthogonal frequency division multiple access (MIMO-OFDMA) system. VBLAST is a successive cancellation method applied to the receiver to obtain the highest SNR. Performance of MIMO systems in realistic radio environments greatly depends on the spatial correlation due to the presence of scatterers in the multipath propagation environments.The number of users using in the system are also analyzed. It is assumed that all antennas have same radiation pattern and the spatial correlation is independent on the position of an antenna in the array. Our results are simulated on Monte Carlo and One Ring channel model for 2x2 MIMO OFDMA system. From the results, we can see that VBLAST-ZF show the best SER performance in one ring channel model with long term evolution (LTE) standard.
Planta Medica, 2010
Two new compounds, an isoflavone (1, 6-methoxybarbigerone) and a bipterocarpan (2, pachylobin) we... more Two new compounds, an isoflavone (1, 6-methoxybarbigerone) and a bipterocarpan (2, pachylobin) were isolated from the grains of Millettia pachyloba (Leguminosae), together with seven known compounds, 5-methoxybarbigerone (3), calopogoniumisoflavone B (4), durmillone (5), jamaicin (6), ichthynone (7), (-)-pisatin (8) and (-)-rotenone (9). The structures were established from spectroscopic analyses, including mass spectrometry and 2D-NMR. Absolute configuration of 2 was proposed based on that of the known compound (-)-pisatine (8). Compounds 1 and 2 exhibited cytotoxicity against KB cells with IC(50) values of 2.0 and 17.6 µM, respectively.
Microbial Cell Factories, 2011
Background Disulfide bonds are one of the most common post-translational modifications found in p... more Background Disulfide bonds are one of the most common post-translational modifications found in proteins. The production of proteins that contain native disulfide bonds is challenging, especially on a large scale. Either the protein needs to be targeted to the endoplasmic reticulum in eukaryotes or to the prokaryotic periplasm. These compartments that are specialised for disulfide bond formation have an active catalyst for their formation, along with catalysts for isomerization to the native state. We have recently shown that it is possible to produce large amounts of prokaryotic disulfide bond containing proteins in the cytoplasm of wild-type bacteria such as E. coli by the introduction of catalysts for both of these processes. Results Here we show that the introduction of Erv1p, a sulfhydryl oxidase and a disulfide isomerase allows the efficient formation of natively folded eukaryotic proteins with multiple disulfide bonds in the cytoplasm of E. coli. The production of disulfide b...
Journal of Natural Products, 2012
Journal of Chromatography B, 2011
International Journal of Behavioral Nutrition and Physical Activity, 2011
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2000
Hybrid nanocomposites based on crystalline nanoparticles dispersed in polymer matrix have been wi... more Hybrid nanocomposites based on crystalline nanoparticles dispersed in polymer matrix have been widely studied in the past few years because of the ability of these materials to combine the properties of organic polymer and inorganic nanoparticles. The aim of this work is to tune the mechanical properties of a piezoelectric polymer by adding nanoparticles to the matrix. In this paper, alumina nanoparticles were dispersed in the copolymer P(VDF-TrFE), which exhibits high piezoelectric coefficient after polarization under high electric field without needing stretching during the polarization process. Transmission electron microscopy and scanning electron microscopy demonstrate the high rate of welldispersed nanoparticles with 10% of alumina nanoparticles added to the matrix. Piezoelectric measurements indicate that P(VDF-TrFE) may be filled by up to 10 wt% of alumina while retaining its high piezoelectric properties and increasing its elastic constant by more than 20%, measured by Brillouin spectroscopy. This work opens a wide range of applications using nanoparticles with nonlinear optical, pyroelectric, magnetic, or ferroelectric properties.
BMC Health Services Research, 2012
Addiction, 2008
To provide an overall picture of drug abuse in Vietnam, its prevalence, correlates and patterns. ... more To provide an overall picture of drug abuse in Vietnam, its prevalence, correlates and patterns. Studies addressing the drug abuse problem in Vietnam are reviewed. Attention is paid to studies conducted from 1993 onwards. The reviewed studies were collected from both refereed and non-refereed sources. Drug abuse is rising sharply in Vietnam: almost threefold over the past 10 years. From a predominantly rural-mountainous phenomenon, illicit drug abuse spread rapidly to urban areas. Meanwhile, the average age of drug users has declined and more women have been engaging in drug consumption. At the same time, heroin has replaced opium as the most preferred drug in the country's illicit drug market, especially among young users in urban areas. At the national level, the second main route of drug administration, injecting, has exceeded smoking and taken precedence in the…
Six field foot-and-mouth disease viruses (FMDVs), including four serotype O and two serotype Asia... more Six field foot-and-mouth disease viruses (FMDVs), including four serotype O and two serotype Asia 1 strains, were collected from endemic outbreaks in 2005, 2006, and 2007 from four different provinces in Vietnam. The viruses were isolated and genetically characterized for their complete genomic sequences. The genetic analysis based on the complete genomic coding sequences revealed that the four serotype O FMDVs were related to each other, sharing 95.2% nucleotide (nt) identity and 97.5-97.6% amino acid (aa) identity. Genetic analysis and a phylogenetic tree, based on the VP1 gene of FMDV, showed that the four present Vietnamese serotype O strains have a high level of identity with other serotype O representatives of the Mya-98 lineage of the Southeast Asian (SEA) topotype. The four viruses were all clustered into the Mya-98 lineage of the SEA topotype, sharing 92.3-95.6% nt and 93.4-96.7% aa identity. This finding of the Mya-98 lineage was different from previous reports that the Vietnamese serotype O strains belonged to the Cam-94 lineage of the SEA topotype and two other topotypes, Middle East-South Asia (ME-SA) and Cathay. For the two serotype Asia 1 FMDVs, the genetic analysis based on the complete genomic coding sequences as well as on the VP1 gene revealed that they belonged to two genogroups, IV and V. Of note, the As1/VN/QT03/2007 strain of genogroup V, isolated in 2007, was very closely related to the pandemic Asia 1 strain which caused FMD outbreaks in China (Asia1/WHN/CHA/06, FJ906802) and Mongolia (Asia1/MOG/05, EF614458) in 2005, sharing 99.0-99.3% nt and 99.5-100% aa identity. In contrast, the second strain As1/VN/LC04/2005 of genogroup IV, isolated in 2005, was closely related to all referenced Vietnamese serotype Asia 1 strains found in the GenBank databases, sharing 86.4-100% nt and 90.9-100% aa identity with each. This study is the first description of the full-length genomic sequence of Vietnamese FMDV serotypes O and Asia 1 and may provide the evidence of the concurrent circulation of different serotypes and subtypes of FMDV in recent years in Vietnam.