Increased Progastrin-Releasing Peptide Expression is Associated with Progression in Gastric Cancer Patients

Li Li,Xiaodong Yin,Hai Meng,Juanyu Hu,Zhengqing Yu,Jianyong Xu 연세대학교의과대학 2020 Yonsei medical journal Vol.61 No.1

Purpose: The purpose of this study was to assess the diagnostic and prognostic value of serum progastrin-releasing peptide(ProGRP) in patients with gastric cancer (GC). Materials and Methods: A total of 150 patients with GC (89 males and 61 females) were recruited, including those with stage I(n=28), stage II (n=33), stage III (n=50), and stage IV (n=39) disease; 50 healthy controls and 66 patients with benign gastric diseaseswere also enrolled. Levels of serum ProGRP, carcinoembryonic antigen (CEA), and carbohydrate antigen 72-4 (CA72-4)were measured in all subjects. Results: Serum ProGRP levels were significantly higher in GC patients than in controls (p<0.001), and ProGRP was significantlycorrelated with tumor size, tumor node metastasis stage, differentiation, invasion depth, and lymph node metastasis (p< 0.005). ProGRP levels were significantly decreased after chemotherapy (p<0.001). Receiver operating characteristic curves revealed a sensitivityand specificity for serum ProGRP in GC of 85.9% and 81.2%, respectively. ProGRP levels were positively correlated withCA72-4 and CEA (r=0.792 and 0.688, p<0.05, respectively). Combined detection of ProGRP, CEA, and CA72-4 showed the best diagnosticpower for GC. Conclusion: ProGRP may be useful as a potential biomarker for GC diagnosis and therapy.

Theoretical investigation on rain-wind induced vibration of a continuous stay cable with given rivulet motion

Li, Shouying,Chen, Zhengqing,Li, Shouke Techno-Press 2014 Wind and Structures, An International Journal (WAS Vol.19 No.5

A new theoretical model on rain-wind induced vibration (RWIV) of a continuous stay cable is developed in this paper. Different from the existing theoretical analyses in which the cable was modeled as a segmental rigid element, the proposed scheme focuses on the in-plane and out-of-plane responses of a continuous stay cable, which is identical with the prototype cable on cable-stayed bridge. In order to simplify the complexities, the motion law of the rivulet on the cable surface is assumed as a sinusoidal way according to some results obtained from wind tunnel tests. Quasi-steady theory is utilized to determine the aerodynamic forces on the cable. Equations of motion of the cable are derived in a Cartesian Coordinate System and solved by using finite difference method to obtain the in-plane and out-of-plane responses of the cable. The results show that limited cable amplitudes are achieved within a limited range of wind velocity, which is a unique characteristic of RWIV of stay cable. It appears that the in-plane cable amplitude is much larger than the out-of-plane cable amplitude. Rivulet frequency, rivulet distribution along cable axis, and mean wind velocity profile, all have significant effects on the RWIV responses of the prototype stay cable. The effects of damping ratio on RWIVs of stay cables are carefully investigated, which suggests that damping ratio of 1% is needed to well mitigate RWIVs of prototype stay cables.

Method applied to evaluate heat leakage of cryogenic vessel for liquid hydrogen

Zhengqing Li,Shengsheng Yang,Xiaojun Wang,Yafei Yuan 한국초전도저온학회 (구 한국초전도저온공학회) 2021 한국초전도저온공학회논문지 Vol.23 No.1

Aerodynamic stability of iced stay cables on cable-stayed bridge

Li, Shouying,Wu, Teng,Huang, Tao,Chen, Zhengqing Techno-Press 2016 Wind and Structures, An International Journal (WAS Vol.23 No.3

Ice accretions on stay cables may result in the instable vibration of galloping, which would affect the safety of cable-stayed bridges. A large number of studies have investigated the galloping vibrations of transmission lines. However, the obtained aerodynamics in transmission lines cannot be directly applied to the stay cables on cable-stayed bridges. In this study, linear and nonlinear single degree-of-freedom models were introduced to obtain the critical galloping wind velocity of iced stay cables where the aerodynamic lift and drag coefficients were identified in the wind tunnel tests. Specifically, six ice shapes were discussed using section models with geometric scale 1:1. The results presented obvious sudden decrease regions of the aerodynamic lift coefficient for all six test models. Numerical analyses of iced stay cables associated to a medium-span cable-stayed bridge were carried out to evaluate the potential galloping instability. The obtained nonlinear critical wind velocity for a 243-meter-long stay cable is much lower than the design wind velocity. The calculated linear critical wind velocity is even lower. In addition, numerical analyses demonstrated that increasing structural damping could effectively mitigate the galloping vibrations of iced stay cables.

Identification and characterization of conserved and novel miRNAs in different development stages of Atrijuglans hetaohei Yang (Lepidoptera: Gelechioidea)

Zhengqing Zhang,Tianfeng Li,Guanghui Tang 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.1

Atrijuglans hetaohei Yang (Lepidoptera: Gelechioidea) is a kind of walnut pest, which mainly damage Juglans regia(Juglandales: Juglandaceae) and is widely distributed in China. The information of microRNAs, e.g., the conservedand novel miRNAs of this species is still unknown. In the present study, the miRNAs in larval and adultstages of A. hetaohei were identified by high throughput sequencing with reference to the genome database of theBombyx mori. A total of 132 conserved miRNAs belonging to 64 families and seven novel miRNAs were obtained,among which 118 miRNAs were identified in both libraries, 4 and 17 miRNAs were only detected to adultspecificand larval-specific libraries, respectively. The most abundant miRNAs in A. hetaohei were miR-1a-3p, let-7, miR-2766 and miR-184. Comparative analysis revealed that 4 novel miRNAs and 47 conserved miRNAs weredifferentially expressed (P < 0.05) between two libraries. Abundance changes of miRNAs were observed fromlarva to adult: 19 miRNAs were up-regulated and 21 miRNAs were down-regulated. The metamorphosis andapoptosis associated miRNAs including miR-1a-3p, miR-133, let-7, miR-2766, miR-184 and miR-34 were discussedfor their predicted functions in insect development. The different expressions of these miRNAs wererelevant to dorso-ventral axis formation, phototransduction, insect hormone biosynthesis, circadian rhythm andmitogen-activated protein kinase (MAPK) signaling pathway. qRT-PCR analysis of ten miRNAs showed similarexpression patterns as high throughput analysis, most miRNAs were highly expressed in adult stage, while miR-8-3p, miR-305-3p and miR-2766 were highly expressed in larvae. The results preliminarily revealed the characterizationof conserved and novel miRNAs in different development stages of A. hetaohei. The different expressionsand associated functions of these miRNAs will provide a basis for understanding post-transcriptionallevel during A. hetaohei development and growth.

Mitigation of wind-induced responses of cylinder solar tower by a tiny eddy current tuned mass damper based on elastic wind tunnel tests

Min Liu,Shouying Li,Zhengqing Chen 국제구조공학회 2020 Smart Structures and Systems, An International Jou Vol.26 No.5

Solar towers, which often has a large aspect ratio and low fundamental natural frequency, were extremely prone to large amplitude of wind-induced vibrations, especially Vortex-Induced Vibration (VIV). A tiny Tuned Mass Damper (TMD) with conveniently adjustable eddy current damping was specially designed and manufactured for elastic wind tunnel tests of a solar tower. A series of numerical simulations by using the COMSOL software were conducted to determine three key parameters, including the thickness of the back iron plate and the conductive plate (<i>T_b</i> and <i>T_c</i>), the distance between the magnet and the conductive plate (<i>T_d</i>). Based on the results of numerical simulations, a tiny TMD was manufactured and its structural parameters were experimentally identified. The optimized values of the tiny TMD can be conveniently realized. The tiny TMD was installed at the top of the elastic test model of a 243-meter-high solar tower, and a series of wind tunnel tests were carried out to examine the effectiveness of the TMD in suppressing wind-induced responses of the test model. The results showed that the wind-induced responses could be obviously reduced by the TMD, especially in the cross-wind direction. The cross-wind RMS and peak responses at the critical wind velocity can be reduced by about 86% and 75%, respectively. However, the maximum reduction of the responses at the design wind velocity is about 45%, obviously less than that at the critical wind velocity.

Experimental and numerical studies of aerodynamic forces on vehicles and bridges

Yan Han,C.S. Cai,Jiexuan Hu,Zhengqing Chen,Chunguang Li 한국풍공학회 2013 한국풍공학회지 Vol.17 No.2

An accurate identification of the aerodynamic characteristics of vehicles and the bridge is the premise for the coupled vibration analysis of a wind-vehicle-bridge system. At present, the interaction of aerodynamic forces between the road vehicles and bridge is ignored in most previous studies. In the present study, an experimental setup was developed to measure the aerodynamic characteristics of vehicles and the bridge for different cases in a wind tunnel considering the aerodynamic interference. The influence of the wind turbulence, the wind speed, the vehicle interference, and the vehicle position on the aerodynamic coefficients of vehicles, and the influence of vehicles on the static coefficients of the bridge were investigated, based on the experimental results. The variations in the aerodynamic characteristics of vehicles and the bridge were studied and the measured results were validated according to the results of surface pressure measurements on the vehicle and the bridge. The measured results were further validated by comparing the measured results with values derived numerically. The measured results showed that the wind turbulence, the vehicle interference, and the vehicle position significantly affected the aerodynamic coefficients of vehicles. However, the influence of the wind speed on the aerodynamic coefficients of the studied vehicle is small. The static coefficients of the bridge were also significantly influenced by the presence of vehicles.

Energy-Aware Preferential Attachment Model for Wireless Sensor Networks with Improved Survivability

( Rufei Ma ),( Erwu Liu ),( Rui Wang ),( Zhengqing Zhang ),( Kezhi Li ),( Chi Liu ),( Ping Wang ),( Tao Zhou ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.7

Recent years have witnessed a dramatic increase in topology research of wireless sensor networks (WSNs) where both energy consumption and survivability need careful consideration. To balance energy consumption and ensure survivability against both random failures and deliberate attacks, we resort to complex network theory and propose an energy-aware preferential attachment (EPA) model to generate a robust topology for WSNs. In the proposed model, by taking the transmission range and energy consumption of the sensor nodes into account, we combine the characters of Erdos -Renyi (ER) model and Barabasi-Albert (BA) model in this new model and introduce tunable coefficients for balancing connectivity, energy consumption, and survivability. The correctness of our theoretic analysis is verified by simulation results. We find that the topology of WSNs built by EPA model is asymptotically power-law and can have different characters in connectivity, energy consumption, and survivability by using different coefficients. This model can significantly improve energy efficiency as well as enhance network survivability by changing coefficients according to the requirement of the real environment where WSNs deployed and therefore lead to a crucial improvement of network performance.

Experimental and numerical studies of aerodynamic forces on vehicles and bridges

Han, Yan,Hu, Jiexuan,Cai, C.S.,Chen, Zhengqing,Li, Chunguang Techno-Press 2013 Wind and Structures, An International Journal (WAS Vol.17 No.2

An accurate identification of the aerodynamic characteristics of vehicles and the bridge is the premise for the coupled vibration analysis of a wind-vehicle-bridge system. At present, the interaction of aerodynamic forces between the road vehicles and bridge is ignored in most previous studies. In the present study, an experimental setup was developed to measure the aerodynamic characteristics of vehicles and the bridge for different cases in a wind tunnel considering the aerodynamic interference. The influence of the wind turbulence, the wind speed, the vehicle interference, and the vehicle position on the aerodynamic coefficients of vehicles, and the influence of vehicles on the static coefficients of the bridge were investigated, based on the experimental results. The variations in the aerodynamic characteristics of vehicles and the bridge were studied and the measured results were validated according to the results of surface pressure measurements on the vehicle and the bridge. The measured results were further validated by comparing the measured results with values derived numerically. The measured results showed that the wind turbulence, the vehicle interference, and the vehicle position significantly affected the aerodynamic coefficients of vehicles. However, the influence of the wind speed on the aerodynamic coefficients of the studied vehicle is small. The static coefficients of the bridge were also significantly influenced by the presence of vehicles.