Comparison of Two Cases of Strong Increase in the Bottom Temperature in the Yellow Sea in Winter

Lian-Gang Lü,Guang-Bing Yang,Zong-Wei Liu,Ying Jiang,Chunmei Yang,Chao Zhang 한국해양과학기술원 2015 Ocean science journal Vol.50 No.3

Mooring observations were carried out on the western slope of the southern Yellow Sea (YS) to observe the Yellow Sea Warm Current (YSWC). Strong increases in the bottom temperature (about 3°C within 1 day) were observed at mooring M5 (shelf break) on 8 January 2007, and at mooring A2 (mid-slope) on 5 December 2008. The strong temperature increase of bottom water at M5 was closely related to the burst of the YSWC. The bottom temperature at mooring A2 increased and decreased alternately from 7 November to 14 December 2008, and the strong increase (about 3°C within 1 day) occurring on 5 December was one of the four rises during that period. The significant semi-diurnal-oscillation during that period indicated that the thermal fronts outlining the Yellow Sea Cold Water Mass (YSCWM) boundary was very close to location A2. The notable rises in the bottom temperature at A2 were associated with bottom eastward currents, while the distinct falls in temperature coincide with bottom westward currents. The distinctive distribution in the bottom temperature associated with the YSCWM and the bottom eastward currents were mainly responsible for the strong increase in the bottom temperature at A2. The variations in the bottom temperature described here are valuable for understanding the time evolution of the YSWC in winter and the YSCWM from late autumn to early winter.

Stress concentration factors test of reinforced concrete-filled tubular Y-joints under in-plane bending

Chao Yang,Jun-fen Yang,Mingzhou Su,Ming Lian 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.22 No.1

To study the stress concentration factors (SCFs) of concrete-filled tubular Y-joints subject to in-plane bending, experiments were used to investigate the hot spot stress distribution along the intersection between chord and brace. Three concrete-filled tubular chords forming Y-joints were tested with different reinforcing components, including doubler-plate, sleeve, and haunch-plate reinforcement. In addition, an unreinforced joint was also tested for comparison. Test results indicate that the three different forms of reinforcement effectively reduce the peak SCFs compared with the unreinforced joint. The current research suggests that the linear extrapolation method can be used for chords, whereas the quadratic extrapolation method must be used for braces. The SCF is effectively reduced and more evenly distributed when the value of the axial compression ratio in the chord is increased. Furthermore, the SCFs obtained from the test results were compared to predictions from some well-established SCF equations. Generally, the predictions from those equations are very consistent for braces, but very conservative for concretefilled chords.

D101 is critical for the function of AttJ, a repressor of quorum quenching system in Agrobacterium tumefaciens

Chao Wang,Chunlan Yan,Yong-Gui Gao,Lian-Hui Zhang 한국미생물학회 2015 The journal of microbiology Vol.53 No.9

The quorum quenching system of Agrobacterium tumefaciens is specifically activated upon entering the stationary phase. Evidence has shown that this system includes two key components: the IclR-type transcriptional factor AttJ (also named as BlcR) and the AHL-lactonase AttM (also named as BlcC). At exponential phase, AttJ binds to the promoter region of attM and thus suppresses the expression of attM. At stationary phase, however, the small molecule SSA directly binds to AttJ and relieves its inhibition of AttJ and thereby triggers the expression of attM. While the regulation of AttM has been extensively investigated, little is known about the regulation of AttJ. In this study, we demonstrated the D101 amino acid of AttJ is essential for the AttJ function. In vitro, the variant protein of AttJD101H appeared to be readily aggregated. In vivo, the D101H mutation in AttJ entirely abolished the inhibitory activity of AttJ and overexpressed attM in A. tumefaciens A6. In addition, D101H mutation led to an overexpression of attJ, indicating an auto-regulatory mechanism for the attJ regulation. Put together, these findings demonstrate that D101 is an important amino acid for the transcription activity of AttJ and the transcription of attJ is regulated by a negative feedback loop. These results expand previous biochemical characterization of AttJ and provide new mechanistic insights into the regulation of quorum quenching in A. tumefaciens.

A detection method of Escherichia coli O157:H7 based on immunomagnetic separation and aptamers-gold nanoparticle probe quenching Rhodamine B’s fluorescence

Fengnan Lian,Dan Wang,Shuo Yao,Lirui Ge,Yue Wang,Yuyi Zhao,Jinbin Zhao,Xiuling Song,Chao Zhao,Jinhua Li,Yajuan Liu,Minghua Jin,Kun Xu 한국식품과학회 2021 Food Science and Biotechnology Vol.30 No.8

This research aimed to detect Escherichia coli O157:H7 in milk based on immunomagnetic probe separation technology and quenching effect of gold nanoparticles to Rhodamine B. Streptavidin-modified magnetic beads (MBs) were combined with biotin-modified antibodies to capture E. coli O157:H7 specifically. Gold nanoparticle (AuNPs) was incubated with sulfhydryl-modified aptamers (SH-Aptamers) to obtain the Aptamers-AuNPs probe. After magnetic beads captured target bacteria and formed a sandwich structure with the gold nanoprobe, Rhodamine B was added into complex to obtain fluorescent signal changes. Our results demonstrated that the established method could detect E. coli O157:H7 in the range of 101–107 CFU/mL, and the limit of detection (LOD) was 0.35 CFU/mL in TBST buffer (pH = 7.4). In milk simulation samples, the LOD of this method was 1.03 CFU/mL. Our research provides a promising approach on the detection of E. coli O157:H7.

FRChain: A Blockchain-based Flow-Rules-oriented Data Forwarding Security Scheme in SDN

( Weichen Lian ),( Zhaobin Li ),( Chao Guo ),( Zhanzhen Wei ),( Xingyuan Peng ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.1

As the next-generation network architecture, software-defined networking (SDN) has great potential. But how to forward data packets safely is a big challenge today. In SDN, packets are transferred according to flow rules which are made and delivered by the controller. Once flow rules are modified, the packets might be redirected or dropped. According to related research, we believe that the key to forward data flows safely is keeping the consistency of flow rules. However, existing solutions place little emphasis on the safety of flow rules. After summarizing the shortcomings of the existing solutions, we propose FRChain to ensure the security of SDN data forwarding. FRChain is a novel scheme that uses blockchain to secure flow rules in SDN and to detect compromised nodes in the network when the proportion of malicious nodes is less than one-third. The scheme places the flow strategies into blockchain in form of transactions. Once an unmatched flow rule is detected, the system will issue the problem by initiating a vote and possible attacks will be deduced based on the results. To simulate the scheme, we utilize BigchainDB, which has good performance in data processing, to handle transactions. The experimental results show that the scheme is feasible, and the additional overhead for network performance and system performance is less than similar solutions. Overall, FRChain can detect suspicious behaviors and deduce malicious nodes to keep the consistency of flow rules in SDN.

Protective effect of acacetin on sepsis-induced acute lung injury via its anti-inflammatory and antioxidative activity

Li-chao Sun,Hong-bo Zhang,Cheng-Dong Gu,Shi-Dong Guo,Gang Li,Rui Lian,Yao Yao,Guo-qiang Zhang 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.12

Sepsis is a clinical syndrome with no effective protective or therapeutic treatments. Acacetin, a natural flavonoid compound, has anti-oxidative and anti-inflammatory effects which can potentially work to reduce sepsis. We investigated the potential protective effect of acacetin on sepsis-induced acute lung injury (ALI) ALI and dissect out the underlying mechanisms. Mice were divided into five groups: a sham group, a sepsis-induced ALI group, and three sepsis groups pre-treated with 20, 40, and 80 mg/kg body weight of acacetin. We found that acacetin significantly attenuated sepsis-induced ALI, in histological examinations and lung edema. Additionally, acacetin treatment decreased protein and inflammatory cytokine concentration and the number of infiltrated inflammatory cells in BALF compared with that in the non-treated sepsis mice. Pulmonary myeloperoxidase (MPO) activity was lower in the acacetin-pre-treated sepsis groups than in the sepsis group. The mechanism underlying the protective effect of acacetin on sepsis is related to the regulation of certain antioxidation genes, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), superoxide dismutases (SODs), and heme oxygenase 1 (HO-1).Taken together, our results indicate that acacetin pre-treatment inhibits sepsis-induced ALI through its anti-inflammatory and antioxidative activity, suggesting that acacetin may be a potential protective agent for sepsis-induced ALI.

Fine-grained Tungsten Heavy Alloy by Mechanical Alloying and Yttrium Oxide Addition

Fan Jing-Lian,Cheng Hui-Chao,Huang Bai-Yun,Liu Tao,Wang Deng-Long 한국분말야금학회 2006 한국분말야금학회 학술대회논문집 Vol.2006 No.1

Pin-Slot Clearance Joints in Multibody Systems

Wei Li,Chao Wang,Chao-lian Sheng,Hai Yang,En Lu 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.12

The pin-slot joint is one of the most commonly used form of kinematic pairs, which with clearance will have a significant effect on the motion and dynamic response of multibody systems. In this study, the multibody system with a pin-slot clearance joint is modeled and the kinematic and dynamic effects are studied. Firstly, the generalized coordinate systems were established and the motion constraint equations of the pin-slot clearance joint were derived. Then, the theories of kinematics and dynamics were used to deduce equations of motion and dynamics. Finally, using slider-crank mechanism as the application example, the simulation study of the multibody system with a pin-slot clearance joint was carried out. The results show that there is an impact phenomenon in the moving process of the end slider, and with the increase of the slot angle, the impact phenomenon is earlier and the impact strength is weaker, however, with the increase of the slot value, the time when the impact phenomenon appearing doesn't change while the impact strength increasing. Furthermore, the maximum displacement of the end slider reduces with the increase of the slot value while the maximum value of driving torque doesn't change and the fluctuation of driving torque increased.

Ergostatrien-3β-ol (EK100) from Antrodia camphorata Attenuates Oxidative Stress, Inflammation, and Liver Injury In Vitro and In Vivo

Ting-Yu Chao,Cheng-Chu Hsieh,Shih-Min Hsu,Cho-Hua Wan,Guan-Ting Lian,Yi-Han Tseng,Yueh-Hsiung Kuo,Shu-Chen Hsieh 한국식품영양과학회 2021 Preventive Nutrition and Food Science Vol.26 No.1

Hepatic ischemia/reperfusion (IR) injury is a complication that occurs during liver surgery, whereby hepatic tissue is injured by oxygen deficiency during ischemia, then further damaged by a cascade of inflammatory and oxidative insults when blood is resupplied during reperfusion. Antrodia camphorata is an indigenous fungus in Taiwan and an esteemed Chinese herbal medicine with various bioactivities. This study examined the effect of ergostatrien-3β-ol (EK100), an active compound found in both the fruiting body and mycelia of A. camphorata, on IR injury pathologies in rats and cell models of oxidative and inflammatory stress. Male Sprague-Dawley rats were randomly assigned to receive a vehicle or 5 mg/kg EK100 prior to hepatic IR injury induced by 1 h ischemia followed by 24 h reperfusion, or a sham operation. RAW 264.7 murine macrophages and HepG2 hepatocytes were pretreated with EK100, then inflammation was induced with lipopolysaccharides in the former and oxidative stress was induced with hydrogen peroxide in the latter. EK100 decreased IR-induced elevation in serum levels of alanine aminotransferase and aspartate aminotransferase and lowered levels of the inflammatory cytokines tumor necrosis factor-α, interleukin (IL)-6, and IL-1β. In addition, EK100 significantly reduced hepatic mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2, as well as nitrite production and iNOS gene expression in both hepatocyte and macrophage cell lines. We demonstrated that EK100 exhibits potent protection against hepatic IR injury, which may be used to design strategies to ameliorate liver damage during liver surgery.

CONTROL OF DPPS IN VEHICLE USING FEED-FORWARD DECOUPLING

Hao Chen,Chao Wang,Xi Chen,Xiaomin Lian 한국자동차공학회 2020 International journal of automotive technology Vol.21 No.4

To solve the contradiction between interior space and demand for electricity of vehicle, this paper brings forward the dual-generator parallel power system (DPPS). However, it is difficult to control the voltage and balance output power between two different types of generators simultaneously. Thus, feed-forward control has been developed to accomplish decoupling the target current of two generators, and proportional-integral differential (PID) controllers, with its stability being discussed, are also designed to track desired values. Based on structural analysis of DDPS, the simulation model is built in MATLAB/Simulink to prove the preliminary feasibility of the scheme and provide a reference for the real system. Finally, bench tests have been performed involving the dynamic change in the reference voltage, engine rotating speed, and load, to verify the effectiveness of the proposed method. The results show that it can achieve synchronous control of the output voltage and current ratio of two generators in DPPS.