Embedded-Ge source and drain in InGaAs/GaAs dual channel MESFET

Shang-Chao Hung,Qiuping Luan,Hau-Yu Lin,Shuguang Li,Shoou-Jinn Chang 한국물리학회 2013 Current Applied Physics Vol.13 No.8

We report the first demonstration of n-type IIIeV metal-semiconductor field-effect transistors (nMESFETs) with IV group material hetero-junction source and drain (S/D) technology. A selective epitaxial growth of germanium (Ge) in the recessed gallium arsenide (GaAs) S/D regions is successfully developed using ultra-high vacuum chemical vapor deposition (UHVCVD) system. The dual channel structure includes an additional 10-nm higher mobility n-In0.2Ga0.8As layer on n-GaAs channel and is introduced to further improve the device performance. The n-MESFET, combining embedded-Ge S/D with In0.2Ga0.8As/GaAs channel, exhibits good transfer properties with a drain current on/off ratio of approximately 103. Due to the small barrier height of Ti/In0.2Ga0.8As Schottky contact, a lattice-matched wide bandgap In0.49Ga0.51P dielectric layer is also integrated into the device architecture to build a higher electron Schottky barrier height (SBH) for gate leakage current reduction. The Ti/In0.49Ga0.51P/n-In0.2Ga0.8As Schottky diode shows a comparable leakage level to Ti/n-GaAs with 2 x 10-2 A/cm2 at a gate voltage of -2.0 V.

Just-in-time Learning-aided Nonlinear Fault Detection for Traction Systems of High-speed Trains

Chao Cheng,Xiuyuan Sun,Junjie Shao,Hongtian Chen,Chao Shang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.9

Traction systems in high-speed trains exhibit significant dynamic characteristics, which mainly arise from operation-point changes. Most existing fault detection methods provide static data models for global structures, especially for traditional multivariate statistical analysis methods constrained by constant operating points. The symptoms of incipient faults are slight and easily hidden. Despite the moderate effect of incipient faults, they will compromise the overall performance and remaining life of traction systems in the long run. Therefore, a just-in-time slow feature analysis method is proposed in this study. The salient advantages of the proposed method are: 1) It can be applied to dynamic non-linear systems; 2) It can detect incipient faults subject to environments containing noise and unknown disturbances; 3) It mitigates false alarms caused by parameter mutation during mode-switching. A series of experiments are carried out on a traction system platform to verify the effectiveness and superiority of the proposed method.

Influence of the MACC1 Gene on Sensitivity to Chemotherapy in Human U251 Glioblastoma Cells

Shang, Chao,Hong, Yang,Guo, Yan,Liu, Yun-Hui,Xue, Yi-Xue Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.1

Background: This study was conducted to determine the influence of MACC1 expression on chemotherapy sensitivity in human U251 glioblastoma cells. Materials and Methods: Expression of the MACC1 gene in 49 cases of human brain glioma was determined by quantitative real-time PCR. Silencing effects of RNA interference on MACC1 was detected by Western-blotting. Flow cytometry methods and methyl thiazolyl tetrazolium assay (MTT) were used to determine the apoptosis and growth inhibitory rates of the U251 cells with MACC1 silencing. before and after treatment with cisplatin (DDP). Results: MACC1 mRNA in gliomas was up-regulated remarkably, to 158.8% of that in peri-cancerous tissues (P<0.05). The siRNA-MACC1 could inhibit the expression of MACC1 protein significantly (p<0.05), associated with an increase in apoptosis rate from 2.57% to 5.39% in U251 cells and elevation of the growth inhibitory rate from 1.5% to 17.8% (p<0.05 for both). After treatment with DDP at various concentrations (1, 3, $5{\mu}g/ml$), compared with control U251 cells, the apoptosis rate of MACC1-silenced U251 cells rose from 8.41%, 13.2% and 19.5% to 12.8%, 17.8% and 25.8%; the growth inhibitory rate increased from 16.2%, 19.3% and 24.5% to 23.7%, 28.4% and 36.3%. Conclusions: There is a notable relationship between over-expression of MACC1 and the characteristics of glioma cells. Silencing of MACC1 was found to enhance the apoptosis and growth inhibitory rates of U251 glioma cells, and thereby increase their sensitivity to DDP chemotherapy.

Compound effects of operating parameters on burnup credit criticality analysis in boiling water reactor spent fuel assemblies

Shang-Chien Wu,Der-Sheng Chao,Jenq-Horng Liang 한국원자력학회 2018 Nuclear Engineering and Technology Vol.50 No.1

This study proposes a new method of analyzing the burnup credit in boiling water reactor spent fuelassemblies against various operating parameters. The operating parameters under investigation includefuel temperature, axial burnup profile, axial moderator density profile, and control blade usage. Inparticular, the effects of variations in one and two operating parameters on the curve of effectivemultiplication factor ðkeff Þ versus burnup ðBÞ are, respectively, the so-called single and compound effects. All the calculations were performed using SCALE 6.1 together with the Evaluated Nuclear Data Files, partB (ENDF/B)-VII238-neutron energy group data library. Furthermore, two geometrical models wereestablished based on the General Electric (GE)14 10 10 boiling water reactor fuel assembly and theGeneric Burnup-Credit (GBC)-68 storage cask. The results revealed that the curves of keff versus B, due tosingle and compound effects, can be approximated using a first degree polynomial of B. However, thereactivity deviation (or changes of keff ; Dk) in some compound effects was not a summation of the allDk resulting from the two associated single effects. This phenomenon is undesirable because it may tosome extent affect the precise assessment of burnup credit. In this study, a general formula was thusproposed to express the curves of keff versus B for both single and compound effects.

Molecular Cloning and Bioinformatic Analysis of SPATA4 Gene

Chao Ai,Zhao Wang,Shang-feng Liu,Zhong-qi Ge,Hai-luo Liu,Bo-wen Liu,Shan He 한국생화학분자생물학회 2005 BMB Reports Vol.38 No.6

Molecular Cloning and Bioinformatic Analysis of SPATA4 Gene

Shang Feng Liu,Chao Ai,Zhong Qi Ge,Hai Luo Liu,Bo Wen Liu,Shan He,Zhao Wang 한국생활환경학회 2005 BMB Reports Vol.38 No.6

Genetic diversity and spread of Lissorhoptrus oryzophilus (Coleoptera: Curculionidae) in China, based on amplified fragment length polymorphism

Shang-Wei Li,Fang-Chao Wei,Juan Du,Mao-Fa Yang 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.3

The rice water weevil (RWW), Lissorhoptrus oryzophilus Kuschel, is one of the most destructive pests causing heavy rice yield loss worldwide. In the present study, amplified fragment length polymorphism (AFLP) was used to analyze the genetic differentiation and transmission routes of 26 RWW geographical populations from Guizhou and 6 other provinces in China. The genetic distance between the 26 populations ranged from 0 to 0.693; the genetic distance between Guizhou and 6 other provinces populations varied from 0.043 to 0.693, with an average of 0.382. There was higher genetic variation among the populations from Guizhou and 6 other provinces compared with populations within Guizhou. The Mantel test showed no correlation between the genetic and geographical distances of the 26 populations. According to genetic distance, clustering, and time that RWW was found in these regions, we deduced that the pest entered Guizhou and spread in this province most likely via three routes: (1) from Hebei to Zunyi and southward to the south-central regions; (2) from Sichuan to Bijie and eastward to the central regions; and (3) from Yunnan through Anshun to the central regions and Qiandongnan prefecture. RWW spread in a natural manner, including flight, crawling, swimming, and by human-associated mechanisms, comprising dissemination through paddies and hay and hitchhiking on human transportations.

Characterization and function of a short peptidoglycan recognition protein from the Chinese oak silkworm, Antheraea pernyi

Li-Shang Dai,Cen Qian, LeiWang,Guo-Qing Wei,Qiu-Ning Liu,Yu Sun,Cong-Fen Zhang,Jun Li,Dong-Ran Liu,Bao-Jian Zhu,Chao-Liang Liu 한국응용곤충학회 2015 Journal of Asia-Pacific Entomology Vol.18 No.4

Peptidoglycan recognition proteins (PGRPs) are conserved proteins in animals from insects to mammals and play an important role in immune response by recognizing peptidoglycan on microbial surfaces. In this study, a PGRP gene from Antheraea pernyi, named Ap-PGRP-A, was isolated and characterized. Sequence analysis revealed that the full-length cDNA of Ap-PGRP-A was 961 bp, containing a 40 bp 5′-untranslated sequence, a 339 bp 3′-untranslated region and an open reading frame of 582 bp. This gene encoded a putative protein of 193 amino acid residues. Phylogenetic analysis indicated that Ap-PGRP-A had the closest protein sequence similarity to Antheraea mylitta PGRP. The recombinant protein was successfully expressed in Escherichia coli cells and a rabbit anti-Ap-PGRP-A antibody was also prepared. Real-time quantitative reverse transcription-PCR analysis showed that Ap-PGRP-A was extensively expressed in the fat body, midgut, hemocyte,malpighian tubule and epidermis of A. pernyi, especially in the fat body and midgut. The expression levels of Ap-PGRP-A were significantly up-regulated by three types of microorganisms, and Ap-PGRP-A expression was more sensitive in response to the Gram-negative bacterium E. coli than the Gram-positive bacterium Bacillus subtilis or the fungus Beauveria bassiana. These data indicate that Ap-PGRP-A may play a role in the innate immune responses of A. pernyi.

Molecular Cloning and Bioinformatic Analysis of SPATA4 Gene

Liu, Shang-Feng,Ai, Chao,Ge, Zhong-Qi,Liu, Hai-Luo,Liu, Bo-Wen,He, Shan,Wang, Zhao Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.6

Full-length cDNA sequences of four novel SPATA4 genes in chimpanzee, cow, chicken and ascidian were identified by bioinformatic analysis using mouse or human SPATA4 cDNA fragment as electronic probe. All these genes have 6 exons and have similar protein molecular weight and do not localize in sex chromosome. The mouse SPATA4 sequence is identified as significantly changed in cryptorchidism, which shares no significant homology with any known protein in swissprot databases except for the homologous genes in various vertebrates. Our searching results showed that all SPATA4 proteins have a putative conserved domain DUF1042. The percentages of putative SPATA4 protein sequence identity ranging from 30% to 99%. The high similarity was also found in 1 kb promoter regions of human, mouse and rat SPATA4 gene. The similarities of the sequences upstream of SPATA4 promoter also have a high proportion. The results of searching SymAtlas (http://symatlas.gnf.org/SymAtlas/) showed that human SPATA4 has a high expression in testis, especially in testis interstitial, leydig cell, seminiferous tubule and germ cell. Mouse SPATA4 was observed exclusively in adult mouse testis and almost no signal was detected in other tissues. The pI values of the protein are negative, ranging from 9.44 to 10.15. The subcellular location of the protein is usually in the nucleus. And the signal peptide possibilities for SPATA4 are always zero. Using the SNPs data in NCBI, we found 33 SNPs in human SPATA4 gene genomic DNA region, with the distribution of 29 SNPs in the introns. CpG island searching gives the data about CpG island, which shows that the regions of the CpG island have a high similarity with each other, though the length of the CpG island is different from each other.This research is a fundamental work in the fields of the bioinformational analysis, and also put forward a new way for the bioinformatic analysis of other genes.

D₂(2317) and D₂(2457) from HQET Sum Rules

Chun Liu,Chao-Shang Huang,Shi-Lin Zhu,Yuan-Ben Dai 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.2

Within the framework of the heavy quark effective theory, QCD sum rules are used to calculate the masses of p-wave cs states. The results for 0+ and 1+ states with the angular momentum of the light component jl = 1=2 are consistent with the experimental values for Ds(2317) and Ds(2457), respectively.