Peptidoglycan activation of the proPO-system without a peptidoglycan receptor protein (PGRP)?

Liu, Haipeng,Wu, Chenglin,Matsuda, Yasuyuki,Kawabata, Shun-ichiro,Lee, Bok Luel,Sö,derhä,ll, Kenneth,Sö,derhä,ll, Irene Elsevier 2011 DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY Vol.35 No.1

<P><B>Abstract</B></P><P>Recognition of microbial polysaccharide by pattern recognition receptors triggers the prophenoloxidase (proPO) cascade, resulting in melanin synthesis and its deposition on the surface of invading pathogens. Several masquerade-like proteins and serine proteinase homologues have been shown to be involved in the proPO activation in insects. In this study, a novel serine proteinase homologue, <I>Pl</I>-SPH2, was found and isolated as a 30kDa protein from hemocytes of the freshwater crayfish, <I>Pacifastacus leniusculus</I>, by its binding property to a partially lysozyme digested or TCA-treated insoluble Lysine (Lys)-type peptidoglycan (PGN) and soluble polymeric Lys-type PGN. Two other proteins, the <I>Pl</I>-SPH1 and lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP) were also found in the several different PGN-binding assays. However no PGRP homologue was detected. Neither was any putative PGRP found after searching available crustacean sequence databases. If RNA interference of <I>Pl</I>-SPH2, <I>Pl</I>-SPH1 or LGBP in the crayfish hematopoietic tissue cell culture was performed, it resulted in lower PO activity following activation of the proPO-system by soluble Lys-type PGN. Taken together, we report for the first time that Lys-type PGN is a trigger of proPO-system activation in a crustacean and that two <I>Pl</I>-SPHs are involved in this activation possibly by forming a complex with LGBP and without a PGRP.</P>

Experimental and numerical research on cavitating flows around axisymmetric bodies

Wei Haipeng,Fu Song,Wu Qin,Huang Biao,Wang Guoyu 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.11

We investigated the cavitating flows around different axisymmetric bodies based on experiments and numerical simulation. In the numericalsimulation, the multiphase Reynolds averaged Navier Stokes equations (RANS) were solved via the commercial computationalfluid dynamics code CFX. The modified k-w SST turbulence model was used along with the transport equation-based cavitation model. In the experiments, a high-speed video technique was used to observe the unsteady cavitating flow patterns, and the dynamic force measurementsystem was used to measure the hydrodynamics of the axisymmetric bodies under different cavitation conditions. Results areshown for the hemisphere bodies, conical bodies and blunt bodies. Reasonable agreements were obtained between the computational andexperimental results. The results show that for the hemispherical body, the cavity consists of quasi-steady transparent region and unsteadyfoggy water-vapor mixture region, which contains small-scale vortices and is dominated by bubble clusters, causing irregulardisturbances at the cavity interfaces. The curvature at the front of the conical body is larger, resulting in that the flow separates at theshoulder of the axisymmetric body. The cavity stretches downstream and reaches to a fixed cavity length and shape. For blunt bodies, theincipient cavitation number is larger than that for the hemispherical body. A large cloud cavity is formed at the shoulder of the blunt bodyin the cores of vortices in high shear separation regions and the re-entrant jet does not significantly interact with the cavity interface whenit moves upstream. As to the dynamic characteristics of unsteady cavitating flows around the axisymmetric bodies, the pulsation frequencyfor the hemispherical body is larger than that for the blunt body. For the hemispherical body, the pulsation is mainly caused bythe high-frequency, small-scale shedding at the rear end of the cavity, while for the blunt body, the main factor for the pulsation frequencyis the periodically shedding of large-scale vortex cavities.

Axial compressive behavior of special-shaped concrete filled tube mega column coupled with multiple cavities

Qiyun Qiao,Haipeng Wu,Wan-Lin Cao,Hongying Dong,Jianwei Zhang 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.23 No.6

The compressive behavior of special-shaped concrete filled tube (CFT) mega column coupled with multiple cavitiesis studied by testing six columns subjected to cyclically uniaxial compressive load. The six columns include three pentagonal specimens and three hexagonal specimens. The influence of cavity construction, arrangement of reinforcement, concrete strength on failure feature, bearing capacity, stiffness, and residual deformation is examined. Experimental results show that cavity construction and reinforcements make it possible to form a combined confinement effect to in-filled concrete, and the two groups of special-shaped CFT columns show good elastic-plastic compressive behavior. As there is no axial bearing capacity calculation method currently available in any Code of practice for special-shaped CFT columns, values predicted by normal CFT column formulas in GB50936, CECS254, ACI-318, EC4, AISCI-LRFD, CECS159, and AIJ are compared with tested values. The calculated values are lower than the tested values for most columns, thus the predicted bearing capacity is safe. A reasonable calculation method by dividing concrete into active and inactive confined regions is proposed. And high accuracy shows in estimating special-shaped CFT columns either coupled with multiple cavities or not. In addition, a finite element method (FEM) analysis is conducted and the simulated results match the test well.

Design of 39-GHz Up- and Down-Conversion Mixers for 5G mmWave TDD Applications

Wang Yi-Yang,Duan Haipeng,He Long,Wu Xu,Wang Dongming,Li Lianming 한국전자파학회 2023 Journal of Electromagnetic Engineering and Science Vol.23 No.2

This article presents fully integrated 39-GHz bidirectional up- and down-conversion mixers for 5G millimeter-wave (mmWave) applications. Fabricated in a 65-nm CMOS process with a 1.2-V supply voltage, the up- and down-conversion mixers consume 39 and 43 mW, respectively. For 5G time-division duplexing (TDD) operation, intermediate-frequency (IF)/local-oscillator (LO)/radio-frequency (RF) T/R switches are introduced. For better isolation and low insertion loss between the up- and down-conversion mixer, a series-shunt singlepole double-throw (SPDT) structure and an equivalent lumped λ/4 transmission line are proposed for IF and RF T/R switches, respectively. To realize compact area and wide bandwidth, a transformer-based matching network is adopted in this design. Targeting multi-channel phased array applications, the measurement result shows that the up-conversion mixer achieves a 2.5-dB peak conversion gain with 6.5 GHz 3-dB bandwidth. Including the insertion loss of the switch and IF signal routing, at the maximum gain of 36.5 GHz, the up-conversion mixer achieves an output 1-dB gain compression point (OP1dB) of 2.5 dBm. Furthermore, the down-conversion mixer achieves a 5-dB peak conversion gain with a 9.7-GHz 3-dB bandwidth.

Elucidating Bottlenecks to the Efficient Preparation of AB₅-Hexamer Mucosal Adjuvant Protein LTm by Genetic Engineering

( Di Liu ),( Fabiao Hu ),( Wenpeng Wang ),( Dong Wu ),( Xiujuan He ),( Wenyun Zheng ),( Haipeng Liu ),( Xingyuan Ma ) 한국미생물생명공학회(구 한국산업미생물학회) 2017 Journal of microbiology and biotechnology Vol.27 No.8

Escherichia coli heat-labile enterotoxin (LT) and its non-toxic mutant (LTm) are well-known powerful mucosal adjuvants and immunogens. However, the yields of these adjuvants from genetically engineered strains remain at extremely low levels, thereby hindering their extensive application in fundamental and clinical research. Therefore, efficient production of these adjuvant proteins from genetically engineered microbes is a huge challenge in the field of molecular biology. In order to explore the expression bottlenecks of LTm in E. coli, we constructed a series of recombinant plasmids based on various considerations and gene expression strategies. After comparing the protein expression among strains containing different recombinant plasmids, the signal sequence was found to be critical for the expression of LTm and its subunits. When the signal sequence was present, the strong hydrophobicity and instability of this amino acid sequence greatly restricted the generation of subunits. However, when the signal sequence was removed, abundantly expressed subunits formed inactive inclusion bodies that could not be assembled into the hexameric native form, although the inclusion body subunits could be refolded and the biological activity recovered in vitro. Therefore, the dilemma choice of signal sequence formed bottlenecks in the expression of LTm. These results reveal the expression bottlenecks of LTm, provide guidance for the preparation of LTm and its subunits, and certainly help to promote efficient preparation of this mucosal adjuvant protein.

Provenance and tectonic setting of the Yimianpo Group in the southeastern Songnen–Zhangguangcai Range Block: constraints on the closure of the Mudanjiang Ocean

Mishan Zhong,Jin Liu,Zhenghong Liu,Jundian Chen,Hongchao Yu,Haipeng Wang,Junshi Lu,Zijie Wu,Mingchen Pan,Liaoning Geological Exploration Institute Co., Ltd.,Yilong Wang 한국지질과학협의회 2023 Geosciences Journal Vol.27 No.4

The timing of the collision between the Songnen–Zhangguangcai Range Block (SNZRB) and the Jiamusi Block (JMSB) is poorly constrained; however, detrital zircons may provide crucial information on the history of this collision. This study focuses on the Yangmugang and Tumenling formations of the Yimianpo Group in the southeastern SNZRB, which were previously thought to have been deposited during the closure of the Mudanjiang Ocean. Detrital zircon U-Pb dating was carried out to constrain the age, provenance, and tectonic setting of the Yangmugang and Tumenling formations, and ultimately the timing of the final closure of the Mudanjiang Ocean. The detrital zircon grains in the two formations yield similar age spectra, with two major age peaks at 275 Ma and 280 Ma, 512 Ma and 525 Ma, respectively. Given the age of the youngest group and that of a granite intrusion, the Yangmugang and Tumenling formations were probably deposited during the middle Permian. The detrital zircon ages also suggest that the Paleozoic igneous rocks distributed across the eastern SNZRB were the major source of the zircons in the formations. Combined with evidence for synchronous arc magmatism, this shows that the Yangmugang and Tumenling formations were likely deposited at a convergent margin and that the collision between the SNZRB and JMSB occurred after the late Permian.