Efficient Expression and Purification of Recombinant Alcohol Oxidase in Pichia pastoris

Yunping Liu,Jianfeng Pan,Peilian Wei,Jianzhong Zhu,Lei Huang,Jin Cai,Zhinan Xu 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.4

In order to improve the production of alcohol oxidase (AOX), a recombinant Pichia pastoris (P. pastoris)system was constructed by transformation of the plasmid pPIC9K-AOX into P. pastoris GS115. The effects of different expression conditions on alcohol oxidase activity in the culture supernatant were investigated in the shake flask scale. The results showed that the highest extracellular activity (562 U/L) of alcohol oxidase was obtained after 56h induction with 4% methanol at OD600 1.0 in the medium containing 50 g/L maltose, which is about 4.2 folds higher than previously reported. High-purity functional recombinant AOX (>90%) was purified from the culture with the Ni-NTA affinity column and Sephadex G-100 chromatographical methods, with a total recovery rate of 68.9%. Further studies showed that the purified rAOX had similar enzymatic characteristics as the native enzyme, except that the thermal stability and resistance to H2O2 inhibition of rAOX were significantly greater compared to the previous report. The purified rAOX was well tolerant to various water-miscible organic solvents. This efficient expression and purification process will be promising for large-scale production of rAOX as an important diagnostic enzyme for alcohol detection in many areas.

Nonlinear aerodynamic stability analysis of orthotropic membrane structures with large amplitude

Zhoulian Zheng,Yunping Xu,Changjiang Liu,Xiaoting He,Weiju Song 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.37 No.4

The aerodynamic stability of orthotropic tensioned membrane structures with rectangular plane is theoretically studied under the uniform ideal potential flow. The aerodynamic force acting on the membrane surface is determined by the potential flow theory in fluid mechanics and the thin airfoil theory in aerodynamics. Then, based on the large amplitude theory and the D'Alembert's principle, the interaction governing equation of wind-structure is established. Under the circumstances of single mode response, the Bubnov-Galerkin approximate method is applied to transform the complicated interaction equation into a system of second order nonlinear differential equation with constant coefficients. Through judging the stability of the system characteristic equation, the critical divergence instability wind velocity is determined. Finally, from different parametric analysis, we can conclude that it has positive significance to consider the characteristics of orthotropic and large amplitude for preventing the instability destruction of structures.

A Method for Mapping Sensor Data to SSN Ontology

Xiaoming Zhang,Yunping Zhao,Wanming Liu 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.9

Along with the continuous development of the sensor network technology, sensors from all over the world are constantly producing sensor data. However, the sensor data from different source is hard to work together for lack of semantic. Fortunately, SSN ontology provide a way to represent sensor data semantically, but how to transform sensor data into the instance of SSN ontology conveniently is still an issue to be considered. This paper proposed a solution to map sensor data to SSN ontology automatically based on a predefined XML-based document. We design a mapping language SASML (Sensors Annotation and Semantic Mapping Language) which provide a schema to annotate sensors and sources so as to generate a XML document for mapping. Then, an algorithm (namely SDRM) is designed to automatically transform sensor data, which described by SASML, to RDF conforming to SSN ontology, according to the mapping document and the element correspondences between the SASML and SSN ontology. Further, a case study about sensor data from greenhouse is presented to illustrate our method, and a prototype is also developed to demonstrate the feasibility and effectiveness.

The coupling effect of drying shrinkage and moisture diffusion in concrete

A. Suwito,Ayman Ababneh,Yunping Xi,Kaspar Willam 한국계산역학회 2006 Computers and Concrete, An International Journal Vol.3 No.2

Drying shrinkage of concrete occurs due to the loss of moisture and thus, it is controlled by moisture diffusion process. On the other hand, the shrinkage causes cracking of concrete and affects its moisture diffusion properties. Therefore, moisture diffusion and drying shrinkage are two coupled processes and their interactive effect is important for the durability of concrete structures. In this paper, the two material parameters in the moisture diffusion equation, i.e., the moisture capacity and humidity diffusivity, are modified by two different methods to include the effect of drying shrinkage on the moisture diffusion. The effect of drying shrinkage on the humidity diffusivity is introduced by the scalar damage parameter. The effect of drying shrinkage on the moisture capacity is evaluated by an analytical model based on non-equilibrium thermodynamics and minimum potential energy principle for a two-phase composite. The mechanical part of drying shrinkage is modeled as an elastoplastic damage problem. The coupled problem of moisture diffusion and drying shrinkage is solved using a finite element method. The present model can predict that the drying shrinkage accelerates the moisture diffusion in concrete, and in turn, the accelerated drying process increases the shrinkage strain. The coupling effects are demonstrated by a numerical example.

Potential application of ginseng in sepsis: Applications of ginseng in sepsis

Fuxun Yang,Jiajia Li,Yunping Lan,Yu Lei,Fan Zeng,Xiaobo Huang,Xiaoxiu Luo,Rongan Liu The Korean Society of Ginseng 2023 Journal of Ginseng Research Vol.47 No.3

Sepsis and septic shock affect millions of people worldwide each year with high clinical mortality rates. At present, basic research on sepsis has emerged in an endless stream, but there are few effective clinical translation results. Ginseng, a medicinal and edible representative of Araliaceae plants, contains a variety of biologically active compounds including ginsenosides, alkaloids, glycosides, polysaccharides, and polypeptides. Neuromodulation, anticancer activity, blood lipid regulation, and antithrombotic activity have been linked to ginseng treatment. At present, basic and clinical research have suggested various applications of ginseng in sepsis. In view of the different effects of various ginseng components on the pathogenesis of sepsis, and in order to further understand and develop the possible value of ginseng in sepsis, this manuscript reviews the application of various components of ginseng in the treatment of sepsis in recent years.

An experimental study on fire resistance of medical modular block

김형준,조봉호,이재승,김흥열,Yunping Xi,권기혁 국제구조공학회 2013 Steel and Composite Structures, An International J Vol.15 No.1

Fire performance and fire safety of high-rise buildings have become major concerns after thedisasters of World Trade Center in the U.S. in 2001 and Windsor tower in Spain in 2005. Performance baseddesign (PBD) approaches have been considered as a better method for fire resistance design of structuresbecause it is capable of incorporating test results of most recent fire resistance technologies. However, thereis a difficulty to evaluate fireproof performance of large structures, which have multiple structural memberssuch as columns, slabs, and walls. The difficulty is mainly due to the limitation in the testing equipment,such as size of furnace that can be used to carry out fire tests with existing criteria like ISO 834, BS 476, andKS F 2257. In the present research, a large scale calorie meter (10 MW) was used to conduct three full scalefire tests on medical modular blocks. Average fire load of 13.99 kg/m² was used in the first test. In thesecond test, the weighting coefficient of 3.5 (the fire load of 50 kg/ m²) was used to simulate the worst firescenario. The flashover of the medical modular block occurred at 62 minutes in the first test and 12 minutesin the second test. The heat resistance capacity of the external wall, the temperatures and deformations of thestructural members satisfied the requirements of fire resistance performance of 90 minutes burning period. The total heat loads and the heat values for each test are calculated by theoretical equations. The duration ofburning was predicted. The predicted results were compared with the test results, and they agree quite well.

A fractal fracture model and application to concrete with different aggregate sizes and loading rates

Chang, Kug Kwan,Xi, Yunping,Roh, Y.S. Techno-Press 2006 Structural Engineering and Mechanics, An Int'l Jou Vol.23 No.2

Recent developments in fractal theory suggest that fractal may provide a more realistic representation of characteristics of cementitious materials. In this paper, the roughness of fracture surfaces in cementitious material has been characterized by fractal theory. A systematic experimental investigation was carried out to examine the dependency of fracture parameters on the aggregate sizes as well as the loading rates. Three maximum aggregate sizes (4.76 mm, 12.7 mm, and 19.1 mm) and two loading rates (slow and fast loading rate) were used. A total of 25 compression tests and 25 tension tests were performed. All fracture parameters exhibited an increase, to varying degrees, when aggregates were added to the mortar matrix. The fracture surfaces of the specimens were digitized and analyzed. Results of the fractal analysis suggested that concrete fracture surfaces exhibit fractal characteristics, and the fractal geometry provide a useful tool for characterizing nonlinear fracture behavior of concrete. Fractal dimension D was monotonically increased as maximum aggregate sizes increase. A new fractal fracture model was developed which considers the size and shape of aggregate, and the crack paths in the constituent phases. Detailed analyses were given for four different types of fracture paths. The fractal fracture model can estimate fractal dimension for multiphase composites.

Coupled diffusion of multi-component chemicals in nonsaturated concrete

Nattapong Damrongwiriyanupap,Linyuan Li,Yunping Xi 사단법인 한국계산역학회 2013 Computers and Concrete, An International Journal Vol.11 No.3

A comprehensive simulation model for the transport process of fully coupled moisture and multispecies in non-saturated concrete structures is proposed. The governing equations of moisture and ion diffusion are formulated based on Fick’s law and the Nernst-Planck equation, respectively. The governing equations are modified by explicitly including the coupling terms corresponding to the coupled mechanisms. The ionic interaction-induced electrostatic potential is described by electroneutrality condition. The model takes into account the two-way coupled effect of moisture diffusion and ion transport in concrete. The coupling parameters are evaluated based on the available experimental data and incorporated in the governing equations. Differing from previous researches, the material parameters related to moisture diffusion and ion transport in concrete are considered not to be constant numbers and characterized by the material models that account for the concrete mix design parameters and age of concrete. Then, the material models are included in the numerical analysis and the governing equations are solved by using finite element method. The numerical results obtained from the present model agree very well with available test data. Thus, the model can predict satisfactorily the ingress of deicing salts into non-saturated concrete.

RDW-SD and PCT Are Potential Prognostic Factors for In-hospital Death in Patients With Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis

Zhang Lixia,Lan Yunping,Qi Bo,Shuai Ping,Hou Qinchuan,Liu Wei,Wang Qian 대한천식알레르기학회 2023 Allergy, Asthma & Immunology Research Vol.15 No.6

Purpose: Our study aimed to explore potential prognostic factors in Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) patients from easily accessible laboratory data and to investigate whether the combination of these indicators with a score for toxic epidermal necrolysis (SCORTEN) can improve the predictive value. Methods: Data from 85 SJS/TEN patients hospitalized from 2010 to 2021 were retrospectively analyzed. The primary outcome was in-hospital mortality. Univariate analysis was used to screen for laboratory indexes associated with death. Logistic regression was used to analyze significant risk factors for death. The differentiation and calibration of SCORTEN and modified score were assessed using receiver operating characteristic (ROC) curves and Hosmer-Lemeshow goodness-of-fit test. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to evaluate the incremental prognostic value. Results: Among the 85 patients (37 males, 48 females) aged 14-88 years, the mortality rate was 11.8% (n = 10). SCORTEN had good discrimination and calibration to predict mortality in this cohort of patients (area under the ROC curve [AUC] of 0.874, 95% confidence interval [CI], 0.758-0.990; Hosmer-Lemeshow goodness-of-fit test P = 0.994). Red cell distribution width-standard deviation index (RDW-SD) > 47.9 fL and procalcitonin (PCT) > 0.67 ng/mL were significant risk factors for death. When adding the 2 factors to SCORTEN, AUC was 0.915 (95% CI, 0.833–0.997), but not statistically different compared to SCORTEN alone (P = 0.091). The NRI was 1.2 (95% CI, 0.672–1.728; P < 0.001) and the IDI was 0.09 (95% CI, 0.011–0.173; P = 0.026), still suggesting that the modified score had better discriminatory and predictive power than SCORTEN alone. The modified score also showed good calibration (Hosmer-Lemeshow goodness-of-fit test, P = 0.915). Conclusions: SCORTEN is a good predictor of mortality in SJS/TEN patients in southwest China. Combining RDW-SD > 47.9 fL and PCT > 0.67 ng/mL with SCORTEN may enhance the ability to predict prognosis.

FRACTAL SURFACE ROUGHNESS OF CONCRETE

Y.S. Roh,Yunping Xi,L. Chung 한국콘크리트학회 2004 한국콘크리트학회 학술대회 논문집 Vol.2004 No.11