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Wind characteristics of hurricane Gustavo (2008) in the whole process of making landing on Louisiana State of USA is observed and analyzed, including wind speed, wind pressure, temperature, air moisture, rainfall, etc, on the height of 2.5m, 4m, 5m, 7m, 10m. Then, observation data are divided into three stages: pre-hurricane, in-hurricane and post-hurricane. Thereafter, gust factor, turbulence intensity, integral scale, correlation function, and probability distribution function are obtained in time domain on 10min samples. Power spectrum of wind speed in horizontal direction is fitted and averaged in frequency domain. The calculation and observation of HHT spectrum for wind speed on the height of 10m are conducted in time and frequency hybrid domain. Research shows that: Gust factors and turbulence intensities tend to be larger during the pre-hurricane period, while the integral scale shows opposite trend; the averaged values of gust factor is 1. 67; Gust factor increases exponentially with turbulence intensity; The probability density function of fluctuating wind speed of Gustavo (2008) follows a Gaussian distribution; The averaged power spectrum for wind speed in horizontal direction is higher in low-frequency region and lower in high-frequency region compared with the current power spectrums; The fluctuating wind speed for hurricane is shown to be a nonlinearity and instability stochastic process. [ABSTRACT FROM AUTHOR]

The conventional eigen value analysis method (CEVA) has some shortcomings in solving two-dimensional coupled flutter problems, for example, when the frequency ratio of torsional to bending is approaching 1, the pre-selection of frequency and its iteration is a time consuming work. This paper presents an straight forward method for analyzing two-dimensional coupled flutter of super-long-span suspension bridges, utilizing CEVA method and Ferrari's thoughts on solving univariate equations of four degrees, which has both improvements on work process and work time compared with the CEVA method. Case studies of four different cross section suspension bridges (the ideal plate, close steel box, single slotted steel box, and double slotted steel box) are provided to validate the developed procedure as well as to demonstrate the flutter analysis of super-long-span suspension bridges using straight forward method. The proposed method in this paper enables the researchers to make comparison on the flutter modality, flutter stability performance and freedom coupling extent of suspension bridges with different mid-span and different cross sections. [ABSTRACT FROM AUTHOR]

The present paper concentrates on overcoming the deficiency of whole bridge aero-elastic wind tunnel test in the acquisition of dynamic stress of bridge elements. Based on both the whole bridge aero-elastic wind tunnel test and finite element method, some research is implemented with the hanger of Jiangdong Bridge as an example. Firstly, verification analysis for displacements is made on results derived from the above two approaches. Thereafter, regression equation is deduced from finite element method under zero yawed angles since the mid-span vertical displacement time history keeps high correlations with the hanger axial forces. Furthermore, displacement time histories of the mid-main span are sampled from wind tunnel test under different yawed angles. Lastly, with the help of regression equation and wind tunnel test results, the hanger's dynamic stresses are obtained. Research shows that the regression equation in this paper has a significant regress effect in the 95% confidence interval. It is concluded that estimation method in this paper makes up the shortcoming of wind tunnel test for not being able to get structural stresses, and avoids several procedures in finite element method analysis under skew wind excitations, such as the identification of aero-elastic parameters and its complicated framework. [ABSTRACT FROM AUTHOR]

To identify the number of modes of vibration in the random theory results for wind vibration, the empirical mode decomposition (EMD) method and wavelet transform method are used to analyze the joint characteristic for self-induced response signals of aeroelastic model. First, the intrinsic mode functions (IMF) are directly decomposed from original signal with EMD, and then the signal characteristic parameters of every IMF can be extracted with wavelet transform, which are compared with the results by traditional spectrum analysis method and wavelet transform on original signal. The combination of EMD and wavelet transform method can identify the high-order mode of vibration ; the main characteristics of signals in arbitrary frequence band can be obtained ; and the distribution of signal energy with time and frequence can be displayed more clearly. The numerical simulation and the analysis of response signal date show that this method is effective and practical. [ABSTRACT FROM AUTHOR]

Objective: To assess the distribution frequency of Gly82Ser polymorphism of receptor for advanced glycation end products (RAGR) gene and investigate its association with type 2 diabetic Chinese patients., Methods: The allele frequencies and genotype distribution of Gly82Ser polymorphism of RAGE gene were compared in a case-control study of 194 type 2 diabetic and 546 non-diabetic subjects. PCR-restriction fragment length polymorphism (PCR-RFLP) was used for detection of the genotype variants., Results: In general Chinese population and type 2 diabetic Chinese patients, the most frequent genotype and allele of RAGR gene Gly82Ser polymorphism were genotype GG and allele G, whose frequency distribution were significantly higher than those in other countries (P<0.01). No significantly difference in the genotype frequencies or allele frequencies of Gly82Ser polymorphism were found between the diabetic patients and non-diabetic subjects (P>0.05)., Conclusion: Gly82Ser polymorphism of RAGE gene does not demonstrate any association with type 2 diabetes in Chinese patients, but high genotype and allele frequencies of Gly82Ser polymorphism occur in Chinese population and type 2 diabetic Chinese patients.

Objective: To investigate effects of captopril and losartan on the expression of kidney aquaporin-2 (AQP2) mRNA and the excretion of urine AQP2 in rats., Methods: Thirty healthy rats were randomized into 3 groups, namely the control group, captopril group and losartan group, respectively. Blood and urine samples were collected from the rats for detecting serum Na(+), urine volume and urine osmolality in the course of medication. Urine AQP2 concentration was measured by enzyme-linked immunosorbent assay (ELISA). Semi-quantitative RT-PCR was performed for measurement of kidney inner medullary AQP2 and vasopressin V(2) receptor mRNA., Results: Urine volume was increased in rats of captopril and losartan groups as compared with that of the control group. However, urine osmolality was lower in captopril group than in the other two groups (P<0.05). RT-PCR revealed decreased quantity of the inner medullary AQP2 mRNA of the captopril group than that of the other two groups, but the quantity of V(2) receptor mRNA did not differ significantly between the 3 groups. Urine AQP2 concentration was significantly higher in captopril group than in the control (P<0.05) and losartan groups (P0<0.01)., Conclusion: Captopril can reduce the expression of the kidney inner medullary AQP2 mRNA and accelerate the excretion of the urine AQP2 in normal rats.

Objective: To investigate the effects of advanced glycation end-products (AGEs) on transient cytosolic free calcium in neonatal rat cardiac myocytes (CMs) cultured in vitro., Methods: CMs cultured for 3 to 5 days in vitro were incubated with Ca(2+)-sensitive fluorescent indicator Fluo-3AM with light screening at 37 degrees celsius; with 5% CO(2) for 60 min. Changes of the fluorescence signal of free calcium caused by AGEs were measured under laser scanning confocal microscope (LSCM)., Results: Compared with the control cells, AGEs caused an increase in the concentration of cytosolic free calcium in a dose-dependent manner., Conclusion: AGEs may impair neonatal rat CMs by altering cytosolic free calcium concentration.

Objective: To study in vivo calcification and biomechanics of the ultra-microporous expanded polytetrafluo- roethylene (UePTFE) in rabbits in comparison with glutaral-treated bovine pericardium (BP), so as to assess the potential of UePTFE as a material for cardiac valve prosthesis., Methods: Factorial analysis was adopted in the experiment. UePTFE and glutaral-treated BP of appropriate sizes were embedded beneath skin of young New Zealand rabbits, and at 0, 1, 3 and 6 months following the implantation, the materials were measured for the content of calcium and biomechanics properties., Results: Lower level of calcification of the UePTFE occurred after the implantation, as compared with BP, and the biomechanics indices of the former UePTFE were obviously suprior to those of the latter., Conclusion: UePTFE is a better material than BP for cardiac valve prosthesis.