Cloning and Spatiotemporal Expression Analysis of Bombyx mori elav, an Embryonic Lethal Abnormal Visual Gene

Geng Xian Wang,Ying Liu,Yang Hu Sima,Sheng Xiang Zhang,Shi Qing Xu 한국잠사학회 2009 International Journal of Industrial Entomology Vol.18 No.2

Embryonic lethal abnormal visual (elav) is a lethal gene in Drosophila inducing the abnormal development and function of nervous system. We cloned a Bmelav gene by bioinformatics and biological experiment, based on sequence of ELAV protein and dbEST of Bombyx mori. The full-length of Bm-elav cDNA is 1498 bp, contains a 906 bp open read frame (ORF) encoding a precursor of 301 amino acid residues with a calculated molecular weight of 34 kDa and pI of 8.99. Bm-ELAV protein precursor contains three RNA recognition motifs (RRM) in 24~91, 110~177 and 222~295 bit amino acid residues respectively, and belongs to RNA-binding protein family. Bm-ELAV shared varying positives, ranging from 56% to 60% (Identities from 41% to 45%), with RRM from other species of Xenopus tropicalis, Apis mellifera, Tribolium castaneum, Branchiostoma belcheri and Drosophila. Gene localization indicated that Bm-elav is a single-copy gene, gene mapping within 12-chromosome from 7916.68 knt to 7918.16 knt region of nscaf2993. Spatiotemporal expressions pattern analysis revealed that Bm-elav expressed higher in most tested tissues and developmental stages in whole generation, such as silk gland, fat body, midgut, hemopoietic organ and ovary, but almost no expression in terminated diapause eggs. This suggested that the expression of Bm-elav in early developmental embryonic stages might induce abnormal development like in Drosophila. Cloning of the Bmelav gene enables us to test its potential role in controlling pests by transferring the gene into field lepidopteran insects in the future.

Fatigue crack propagation behavior at a notch for needled C/SiC composite under tension-tension loading

Geng Hou,De-Guang Shang,Lin-Xuan Zuo,Lin-Feng Qu,Ming Xia,Yi-Er Guo,Xiang Yin,Shao-Dong Wu 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.1

Fatigue test of a needled C/SiC composite with a notch under tension-tension cyclic loading was completed, and the main fatigue crack propagation curve of the needled composite was obtained by the in situ observation of the fatigue process. By analyzing the influence of the failure number and distribution on the tensile loading subjected by 0° fiber bundles, the relationship between the main fatigue crack propagation and the distribution of 0° fiber bundles in the needled composite was established. By observing the fracture microstructure (especially the distribution of 0° fiber bundles) of the needled composite through scanning electron microscopy, the reasons for the varying fatigue resistance of different notched specimens were also explained. In addition, acoustic emission (AE) was also used to analyze the AE energy characteristics during the fatigue crack propagation process of the needled composite.

A Virtual RLC Active Damping Method for LCL-Type Grid-Connected Inverters

Geng, Yiwen,Qi, Yawen,Zheng, Pengfei,Guo, Fei,Gao, Xiang The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.5

Proportional capacitor-current-feedback active damping (AD) is a common damping method for the resonance of LCL-type grid-connected inverters. Proportional capacitor-current-feedback AD behaves as a virtual resistor in parallel with the capacitor. However, the existence of delay in the actual control system causes impedance in the virtual resistor. Impedance is manifested as negative resistance when the resonance frequency exceeds one-sixth of the sampling frequency ($f_s/6$). As a result, the damping effect disappears. To extend the system damping region, this study proposes a virtual resistor-inductor-capacitor (RLC) AD method. The method is implemented by feeding the filter capacitor current passing through a band-pass filter, which functions as a virtual RLC in parallel with the filter capacitor to achieve positive resistance in a wide resonance frequency range. A combination of Nyquist theory and system close-loop pole-zero diagrams is used for damping parameter design to obtain optimal damping parameters. An experiment is performed with a 10 kW grid-connected inverter. The effectiveness of the proposed AD method and the system's robustness against grid impedance variation are demonstrated.

A Virtual RLC Active Damping Method for LCL-Type Grid-Connected Inverters

Yiwen Geng,Yawen Qi,Pengfei Zheng,Fei Guo,Xiang Gao 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.5

Proportional capacitor–current–feedback active damping (AD) is a common damping method for the resonance of LCL-type grid-connected inverters. Proportional capacitor–current–feedback AD behaves as a virtual resistor in parallel with the capacitor. However, the existence of delay in the actual control system causes impedance in the virtual resistor. Impedance is manifested as negative resistance when the resonance frequency exceeds one-sixth of the sampling frequency (fs/6). As a result, the damping effect disappears. To extend the system damping region, this study proposes a virtual resistor–inductor–capacitor (RLC) AD method. The method is implemented by feeding the filter capacitor current passing through a band-pass filter, which functions as a virtual RLC in parallel with the filter capacitor to achieve positive resistance in a wide resonance frequency range. A combination of Nyquist theory and system close-loop pole-zero diagrams is used for damping parameter design to obtain optimal damping parameters. An experiment is performed with a 10 kW grid-connected inverter. The effectiveness of the proposed AD method and the system’s robustness against grid impedance variation are demonstrated.

Cloning and Spatiotemporal Expression Analysis of Bombyx mori elav, an Embryonic Lethal Abnormal Visual Gene

Wang, Geng-Xian,Liu, Ying,Sim, Yang-Hu,Zhang, Sheng-Xiang,Xu, Shi-Qing Korean Society of Sericultural Science 2009 International Journal of Industrial Entomology Vol.18 No.2

Embryonic lethal abnormal visual (elav) is a lethal gene in Drosophila inducing the abnormal development and function of nervous system. We cloned a Bm-elav gene by bioinformatics and biological experiment, based on sequence of ELAV protein and dbEST of Bombyx mori. The full-length of Bm-elav cDNA is 1498 bp, contains a 906 bp open read frame (ORF) encoding a precursor of 301 amino acid residues with a calculated molecular weight of 34 kDa and pI of 8.99. Bm-ELAV protein precursor contains three RNA recognition motifs (RRM) in $24{\sim}91$, $110{\sim}177$ and $222{\sim}295$ bit amino acid residues respectively, and belongs to RNA-binding protein family. Bm-ELAV shared varying positives, ranging from 56% to 60% (Identities from 41% to 45%), with RRM from other species of Xenopus tropicalis, Apis mellifera, Tribolium castaneum, Branchiostoma belcheri and Drosophila. Gene localization indicated that Bm-elav is a single-copy gene, gene mapping within 12-chromosome from 7916.68 knt to 7918.16 knt region of nscaf2993. Spatiotemporal expressions pattern analysis revealed that Bm-elav expressed higher in most tested tissues and developmental stages in whole generation, such as silk gland, fat body, midgut, hemopoietic organ and ovary, but almost no expression in terminated diapause eggs. This suggested that the expression of Bm-elav in early developmental embryonic stages might induce abnormal development like in Drosophila. Cloning of the Bm-elav gene enables us to test its potential role in controlling pests by transferring the gene into field lepidopteran insects in the future.

Molecular Cloning, Segmental Distribution and Ontogenetic Regulation of Cationic Amino Acid Transporter 2 in Pigs

Zou, Shi-geng,Zhi, Ai-min,Zhou, Xiang-yan,Zuo, Jian-jun,Zhang, Yan,Huang, Zhi-yi,Xu, Ping-Wen,Feng, Ding-yuan Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.5

The goal of this study was to elucidate the expression and segmental distribution of the glomerular cationic amino acid metabolism transporter-2 (CAT-2) and thus to improve our understanding of porcine cationic amino acid transporters and amino acid absorption. Porcine CAT-2 was cloned, sequenced and characterized. The predicted amino acid sequence of porcine CAT-2 shared 86.1% and 92.1% identity with human and mouse CAT-2A, respectively. The tissue distribution patterns and ontogenic changes of CAT-2 mRNAs were determined by real-time Q-PCR. The results showed that porcine CAT-2 was highly expressed in the heart and intestinal tract (duodenum, ileum and jejunum). In addition, the mRNA of CAT-2 was found in liver, lung, kidney, brain and muscle. Within the intestinal tract, CAT-2 mRNA was most abundant in the ileum and rarely expressed in the duodenum. In the duodenum, the levels of CAT-2 mRNA reached their peak on day 7 (p<0.05) while in the jejunum, levels were low on day 1 and 7 and increased rapidly after day 26 before peaking on days 30 and 60 (p<0.05). The levels then dramatically decreased by day 90 (p<0.05). In the ileum, levels achieved their maximum on day 30 and then decreased significantly on day 60 (p<0.05).

Molecular Cloning, Tissue Distribution and Expression of Porcine y⁺L Amino Acid Transporter-1

Zhi, Ai-min,Zhou, Xiang-yan,Zuo, Jian-jun,Zou, Shi-geng,Huang, Zhi-yi,Wang, Xiao-lan,Tao, Lin,Feng, Ding-yuan Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.2

In this study, we cloned, sequenced and characterized porcine y+L Amino Acid Transporter-1 (y+LAT1). By screening a translated EST database with the protein sequence of the human $y^{+}$LAT1 and by using rapid amplification of cDNA ends (RACE), the full-length cDNA encoding porcine $y^{+}$LAT1 was isolated from porcine intestine RNA. It was 2,111 bp long, encoding a 511 amino acid trans-membrane glycoprotein composed of 12 transmembrane domains. The predicted amino acid sequence was found to be 91%, 90%, 87% and 87% identical to those of cattle, human, mouse and rat $y^{+}$LAT1 respectively. Real-time RT-PCR results indicated that the small intestine had the highest $y^{+}$LAT1 mRNA abundance and the lung had the lowest $y^{+}$LAT1 mRNA abundance. Baby hamster kidney (BHK) cells transfected with green fluorescent protein (GFP) tagged porcine $y^{+}$LAT1 cDNA indicated that the cellular localization of the gene product in BHK was on the plasma membrane.

A Significant Reduction of Hysteresis in MnFe(P,Si) Compounds

B. Huliyageqi,Yao-xiang Geng,Ying-jie Li,O. Tegus 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.3

The magnetocaloric effects in Mn1.3Fe0.7−xCoxP0.46Si0.54 compounds (x = 0, 0.025, 0.05 and0.1) were investigated systematically. X-ray diffraction shows that the compounds crystallize in theFe2P-type hexagonal structure with space group P-62m symmetry. Magnetic measurements showthat the paramagnetic-ferromagnetic transition temperatures range from 247 to 298 K. The maximalmagnetic entropy changes in the Mn1.3Fe0.7P0.46Si0.54 compound reaches 8.3 J/kgK for a fieldchange from 0 to 1.5 T. The thermal hysteresis of these compounds is less than 3 K. The maximumadiabatic temperature change is 2.2 K in Mn1.3Fe0.7P0.46Si0.54 and Mn1.3Fe0.65Co0.05P0.46Si0.54compounds for a field change from 0 to 1.48 T, indicating this material system has potential forroom-temperature magnetic refrigeration applications.

Molecular Cloning, Tissue Distribution and Segmental Ontogenetic Regulation of b^0,+ Amino Acid Transporter in Lantang Pigs

Zhi, Ai-Min,Feng, Ding-Yuan,Zhou, Xiang-Yan,Zou, Shi-Geng,Huang, Zhi-Yi,Zuo, Jian-Jun,Ye, Hui,Zhang, Chang-Ming,Dong, Ze-Min,Liu, Zhun Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.8

Cationic amino acid transporter $b^{0,+}AT$ (HGMW-approved gene symbol SLC7A9, solute carrier family 7, member 9) plays a crucial role in amino acid nutrition. In the present study, we describe the cloning and sequencing of porcine $b^{0,+}AT$. Based on the sequence of porcine $b^{0,+}AT$ deposited in the NCBI (National Center for Biotechnological Information), we identified a putative porcine homologue. Using rapid amplification of cDNA ends (RACE), the full-length cDNA encoding porcine $b^{0,+}AT$ was isolated. The porcine $b^{0,+}AT$ cDNA was 1,680 bp long, encoding a 487 amino acid trans-membrane protein. The predicted amino acid sequence was found to have 88.9% and 87.1% identity with human and mouse $b^{0,+}AT$, respectively. Real-time RT-PCR indicated porcine $b^{0,+}AT$ transcripts expressed in heart, kidney, muscle and small intestine. The small intestine had the highest $b^{0,+}AT$ mRNA abundance while the muscle had the lowest (p<0.05). Along the longitudinal axis, the ileum had the highest $b^{0,+}AT$ mRNA abundance while the colon had the lowest (p<0.05). The $b^{0,+}AT$ mRNA level was highest on day 7 and 90 in the duodenum (p<0.05). It increased from day 1 to day 26 in the jejunum (p>0.05) and had the highest abundance on day 60 (p<0.05). There was, however, no difference between day 1, 7, 26, 30, 90 and 150 (p>0.05). The strongest $b^{0,+}AT$ expression appeared on day 7 in the ileum before weaning, and then decreased till day 30 but rose gradually again from day 60 to 150 (p<0.05).

High‑Efficiency Inhibition of Gravity Segregation in Al–Bi Immiscible Alloys by Adding Lanthanum

Peng Jia,Jinyang Zhang,Haoran Geng,Xinying Teng,Degang Zhao,Zhongxi Yang,Yi Wang,Song Hu,Jun Xiang,Xun Hu 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.6

The inhibition of gravity segregation has been a long-standing challenge in fabrication and applications of homogeneousimmiscible alloys. Therefore, the effect of rare-earth La on the gravity segregation of Al–Bi immiscible alloys was investigatedto understand the homogenization mechanism. The results showed that the addition of La can completely suppress thegravity segregation. This is attributed to the nucleation of Bi-rich liquid phase on the in-situ produced LaBi2phase and thechange of the shape of LaBi2@Bi droplets. In addition, a novel strategy is developed to prepare the homogeneous immisciblealloys through the addition of rare-earth elements. This strategy not only is applicable to other immiscible alloys, but alsois conducive to finding more elements to suppress the gravity segregation. This study provided a useful reference for thefabrication of the homogeneous immiscible alloys.