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991.
Nguyen Anh Tuan Pham Thanh Dong Vu Quoc Tru 《Journal of Mechanical Science and Technology》2019,33(7):3277-3288
Journal of Mechanical Science and Technology - This study explores the wake effects of an upstream leading insect on the flight performance of a following one. The potential-flow based aerodynamic... 相似文献
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Anh-Tuan Pham Bernd Meinerzhagen Christoph Jungemann 《Journal of Computational Electronics》2008,7(3):99-102
An efficient discretization of the 2 dimensional (2D) $\vec{k}$ -space and parallelization of the $\vec{k}\cdot \vec{p}$ solver for hole inversion layers is proposed. The 6×6 $\vec{k}\cdot \vec{p}$ Schrödinger equation is solved in parallel for only a small number of grid points in the 2D $\vec{k}$ -space. The subband energy and the generalized probability density function for an arbitrary in-plane wave vector are determined by interpolation based on the resultant eigen states. The fast approach results in accurate inversion densities and also low-field mobilities of holes in unstrained and uniaxially stressed Si channel double-gate MOS structures. 相似文献
995.
Parwinder Kaur Christopher Lui Olga Dudchenko Raja Sekhar Nandety Bhavna Hurgobin Melanie Pham Erez Lieberman Aiden Jiangqi Wen Kirankumar S Mysore 《International journal of molecular sciences》2021,22(9)
Legumes are of great interest for sustainable agricultural production as they fix atmospheric nitrogen to improve the soil. Medicago truncatula is a well-established model legume, and extensive studies in fundamental molecular, physiological, and developmental biology have been undertaken to translate into trait improvements in economically important legume crops worldwide. However, M. truncatula reference genome was generated in the accession Jemalong A17, which is highly recalcitrant to transformation. M. truncatula R108 is more attractive for genetic studies due to its high transformation efficiency and Tnt1-insertion population resource for functional genomics. The need to perform accurate synteny analysis and comprehensive genome-scale comparisons necessitates a chromosome-length genome assembly for M. truncatula cv. R108. Here, we performed in situ Hi-C (48×) to anchor, order, orient scaffolds, and correct misjoins of contigs in a previously published genome assembly (R108 v1.0), resulting in an improved genome assembly containing eight chromosome-length scaffolds that span 97.62% of the sequenced bases in the input assembly. The long-range physical information data generated using Hi-C allowed us to obtain a chromosome-length ordering of the genome assembly, better validate previous draft misjoins, and provide further insights accurately predicting synteny between A17 and R108 regions corresponding to the known chromosome 4/8 translocation. Furthermore, mapping the Tnt1 insertion landscape on this reference assembly presents an important resource for M. truncatula functional genomics by supporting efficient mutant gene identification in Tnt1 insertion lines. Our data provide a much-needed foundational resource that supports functional and molecular research into the Leguminosae for sustainable agriculture and feeding the future. 相似文献
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Subrata Deb Mei Yieng Chin Steven Pham Hans Adomat Antonio Hurtado-Coll Martin E. Gleave Emma S. Tomlinson Guns 《International journal of molecular sciences》2021,22(2)
The peripheral zone (PZ) and transition zone (TZ) represent about 70% of the human prostate gland with each zone having differential ability to develop prostate cancer. Androgens and their receptor are the primary driving cause of prostate cancer growth and eventually castration-resistant prostate cancer (CRPC). De novo steroidogenesis has been identified as a key mechanism that develops during CRPC. Currently, there is very limited information available on human prostate tissue steroidogenesis. The purpose of the present study was to investigate steroid metabolism in human prostate cancer tissues with comparison between PZ and TZ. Human prostate cancer tumors were procured from the patients who underwent radical prostatectomy without any neoadjuvant therapy. Human prostate homogenates were used to quantify steroid levels intrinsically present in the tissues as well as formed after incubation with 2 µg/mL of 17-hydroxypregnenolone (17-OH-pregnenolone) or progesterone. A Waters Acquity ultraperformance liquid chromatography coupled to a Quattro Premier XE tandem quadrupole mass spectrometer using a C18 column was used to measure thirteen steroids from the classical and backdoor steroidogenesis pathways. The intrinsic prostate tissue steroid levels were similar between PZ and TZ with dehydroepiandrosterone (DHEA), dihydrotestosterone (DHT), pregnenolone and 17-OH-pregnenolone levels higher than the other steroids measured. Interestingly, 5-pregnan-3,20-dione, 5-pregnan-3-ol-20-one, and 5-pregnan-17-ol-3,20-dione formation was significantly higher in both the zones of prostate tissues, whereas, androstenedione, testosterone, DHT, and progesterone levels were significantly lower after 60 min incubation compared to the 0 min control incubations. The incubations with progesterone had a similar outcome with 5-pregnan-3,20-dione and 5-pregnan-3-ol-20-one levels were elevated and the levels of DHT were lower in both PZ and TZ tissues. The net changes in steroid formation after the incubation were more observable with 17-OH-pregnenolone than with progesterone. In our knowledge, this is the first report of comprehensive analyses of intrinsic prostate tissue steroids and precursor-driven steroid metabolism using a sensitive liquid chromatography-mass spectrometry assay. In summary, the PZ and TZ of human prostate exhibited similar steroidogenic ability with distinction in the manner each zone utilizes the steroid precursors to divert the activity towards backdoor pathway through a complex matrix of steroidogenic mechanisms. 相似文献
998.
Quang Long Pham Yuvaraj Haldorai Van Hoa Nguyen ChanKyu Kang Jae-Jin Shim 《Korean Journal of Chemical Engineering》2014,31(11):2101-2107
Two highly supercritical CO2-soluble, poly(vinyl acetate) (PVAc)-based macro-reversible addition-fragmentation chain transfer (RAFT) agents were synthesized. The RAFT agents were used for the first time in RAFT/macromolecular design via the interchange of xanthates (MADIX) and polymerization of vinyl acetate (VAc) and vinyl pivalate (VPi) in supercritical carbon dioxide (scCO2). A homopolymer PVAc and a block copolymer PVAc-b-PVPi made by RAFT/MADIX polymerization were characterized, and the effects of time and RAFT agents on polymerization were examined. For the 8.4 wt% RAFT agent in VAc, the molecular mass (M n ) of homopolymer PVAc was 26,000 g mol?1 and PDI was 1.35. For the copolymerization of VPi using 9.8 wt% PVAc-RAFT agent in VPi for 24 h, the M n and PDI of PVAc-b-PVPi reached 32,400 g mol?1 and 1.42, respectively. These results suggest that the polydispersity can be controlled during the clean production of PVAc and PVPi by RAFT/MADIX polymerization in scCO2. 相似文献
999.
Chau Thuy Pham Ning Tang Akira Toriba Kazuichi Hayakawa 《Polycyclic Aromatic Compounds》2015,35(5):355-371
The concentrations of polycyclic aromatic hydrocarbons (PAHs) and nitropolycyclic aromatic hydrocarbons (NPAHs) in total suspended particulates (TSP) and soil were measured at a traffic site in Hanoi, a typical motorcycle city of Vietnam. TSP was collected using high-volume air sampler on Pallflex 2500QAT-UP membrane filters. PAHs and NPAHs were analyzed by high-performance liquid chromatography (HPLC) using fluorescence and chemiluminescence detectors, respectively. The average concentrations of total 10 PAHs and 10 NPAHs in soil varied from 3.4–43.7 ng g?1 and from 112–780 pg g?1 dry weight, respectively, which were much lower than those in TSP. The results showed that large part of the higher molecular weight PAHs in soil, especially benzo[ghi]perylene and benzo[b]fluoranthene came from the atmosphere. However, NPAHs profile showed a different pattern. 3-nitroperylene and 6-nitrochrysene were the most abundant NPAHs in soil, followed by 1-nitropyrene and 6-nitrobenzo[a]pyrene. The fate of NPAHs in soil varied depending on soil properties and chemical structure of NPAHs. The finding that the [NPAH]/[PAH] concentration ratios in soil were different from those in TSP could be due to bio-degradation and/or secondary formation of NPAHs in soil, depending on NPAHs properties. 相似文献
1000.
In this study, the stability and the catalytic activity of an ordered mesoporous SBA-15 immobilized 12-tungstophosphoric acid (H3PW12O40, HPW) in the oxidative desulfurization (ODS) of benzothiophene (BT) and dibenzothiophene (DBT) were improved by a post-synthesis-grafting method. In this method, SBA-15 was functionalized to provide a large number of amine groups for the immobilization of HPW through electrostatic binding with (3-aminopropyl) triethoxysilane (APTES) using triflic acid as a protonated agent. The materials were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), N2 adsorption–desorption, X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The results show that the structure of functionalized SBA-15 support and the active phase of the HPW remained intact after immobilization. The synthesized PW–H3N+-SBA-15 catalyst showed a high catalytic activity for ODS, achieving BT and DBT conversion of 99.9% and 100% with the reaction conditions of reaction temperature of 50?°C, H2O2 dosage of 1?mL, catalyst dosage of 0.03?g, and reaction time 5 and 1?h, respectively. The catalyst also showed a high reusability after up to four cycles, for which the conversion of the fourth reaction was 90.0% for both BT and DBT. 相似文献