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Objective: To explore the correlation between arterial enhancement fraction (AEF) on Computed Tomography (CT) and the curative effect of Transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). Methods: We enrolled 43 patients who presented with HCC to our hospital between January 2019 and January 2020 and extracted their clinical data. Three-phase contrast-enhanced CT was performed 1 month before and after TACE; based on TACE efficacy, the enrolled patients were divided into the “effective” and “ineffective” groups. The alpha-fetoprotein (AFP) level was determined using electrochemical luminescence. Changes in the AEF, AFP level, and tumor size before and after treatment were compared between the two groups. The correlation among AEF, AFP level, and tumor-size changes was explored using Pearson’s correlation coefficient. Receiver operating characteristic (ROC) curves and the area under these curves (AUCs) were used to determine the evaluation value of dynamic enhanced scanning combined with AEF for TACE efficacy. Results: After TACE, the AEF, AFP level, and tumor size decreased in the effective group and were lower than the corresponding values in the ineffective group. Pearson’s correlation analysis revealed that AEF and the AFP level were positively correlated with the tumor size after TACE. ROC analysis revealed that the AUC for dynamic enhanced scanning combined with AEF for TACE efficacy evaluation was 0.902; this was significantly greater than the AUC of dynamic enhanced scanning (0.793) and AEF (0.771) alone. Conclusion: AEF is a reliable parameter for evaluating the therapeutic effect of TACE. The evaluation of TACE efficacy can be further improved by combining AEF with dynamic enhanced scanning; this approach should be used as an auxiliary method for evaluating TACE efficacy for HCC.

There exist intrinsic inter-carrier interference and inter-subsymbol interference in generalized frequency division multiplexing (GFDM) systems.Under condition of time-frequency doubly selective channels, severe effects of pilot contamination would occur and lead to significant performance degradation for the pilot-based channel estimations.To this end, a channel estimation framework for GFDM systems based on deep learning was proposed, which took the low-resolution image constructed with the least squares estimated channel gains of the pilot symbols as input.Consequently, a high-resolution image about the channel time-frequency response was recovered through a deep residual network, and the channel estimation was achieved for GFDM systems.A simulation system for the proposed GFDM time-frequency doubly selective channel estimation algorithm based on deep residual network was developed, and the optimal parameters of the deep residual network were determined through an offline training process.Simulation results show that the proposed algorithm can achieve better performance near to minimum mean square error (MMSE) estimation in terms of estimation error and bit error rate (BER), and has robust Doppler frequency shift generalization capability.

In order to improve the tri-anti-finishing properties of cotton fabric and effectively maintain the original style, the surface morphology, water-repellent, oil-repellent and anti-fouling properties of cotton fabrics after finishing were tested by using self-made fluorosilicone finishing agent, and the washability, physical and mechanical properties of fabric were also investigated. After finishing, the fiber surface of cotton fabric was found to be covered with fluorosilicone polymer and became more smooth, with the static water contact angle of as high as 144.6°, surface moisture resistance grade of 4, oil resistance grade of 4.5 and antifouling grade of 4, respectively. In addition, during 20 cycles, the cotton fabric can maintain excellent water and oil repellency. After finishing, the permeability, whiteness and breaking strength of cotton fabric remained well, but the wrinkle resistance decreased. The self-made finishing agent performs equal to the market product, but the washing resistance still needs to be improved.

The theoretical combination formulas of fluctuating wind-induced structural responses were derived based on mode acceralation and load-response correlation. The consistent coupling method (CCM) for analyzing wind-induced structural responses was firstly presented to compensate the coupling components between background and resonance modes and the equivalent static wind load corresponding to these components was rigorously deduced. The method was employed to analyze wind-induced responses for suspended dome roof structure of Jinan Olympic Sports Hall with the largest span in China. Simultaneous pressure measurements in wind tunnel were done to obtain fluctuating wind loads on the building surface. Main characteristics of wind-induced response of the structure were analyzed, including structural natural frequency, power spectrum of wind-induced response, modal participation in the response, coupling effects among modes, and equivalent static wind load distribution rule of background, resonance and their cross components. Results show that there exist apparent characteristics with multimodal coupling and response in wind induced responses. The cross effects between background and resonance components can' the ignored and resonant component has more contribution to wind-induced response. CCM can he used as a kind of fine and effective method for analyzing wind-induced responses of such structure. [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]

Simultaneous pressure-measured tests on the rigid models for a group of two adjacent large hyperboloidal cooling towers were conducted in TJ - 3 wind tunnel of Tongji University. Mean and fluctuating win pressures were presented for various tower distances and incoming wind angles. Compared with the result of an isolated tower, interference effects produced on each tower by the other one are illustrated by interference factor and quasi-static wind load coefficient. Test results indicate interference effect can't be neglected even when L/D≥3 and the optimal wind direction is 07deg; - 40° if evaluated by the mean CD For tandem and staggered configurations, wind pressure distribution and flow state around the cooling towers are also analyzed. [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]

In order to research the stability performance of cooling tower with gas flue in Xuzhou power plant, the rigid model and aero-elastic model of some super large cooling tower in Tongji TJ - 3 wind tunnel are carried out, the parameters taken to calculate the wind-induced stability performance are gained in the test, with the numerical simulation and the post processor the local and whole stability are analysed. It is found that the local stability safety factor is lower than the norm value, so the reinforcement scheme must be adopted; the whole stability critical wind speed is higher than the designed wind velocity, the critical wind speed would reduce 30% when considering the internal suction; the critical wind speed is gradually small with the increase of the moulding board, the value is 119.41 m/s when the moulding board is 100, which is much higher than the maximum wind speed. [ABSTRACT FROM AUTHOR]

In order to research the influence of super-large cooling tower under earthquake excitation and wind load, the rigid model and aero-elastic model of a super-large cooling tower in the wind tunnel were employed, the data obtained in the test were loaded to calculate the structural response. By the comparison with the response under earthquake excitation, it is obvious that the responses of annular base and tower shell are completely controlled by wind load, and the value under wind load is much greater than that under earthquake excitation. Vertical and hoop forces of tower shell are diminished from the bottom to the top, and the maximums are found at the middle of the tower shell. Their influence on supporting columns is not obvious. 300 modes should be considered in mode analysis method, while 30 modes are only considered when the structural response is calculated under wind load. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to study the effects of simulated acid rain (pH 4.0, 5.0) and Cu (0-200 mg · kg-1) on the physiological characteristics of Paulownia fortunei and its detoxification mechanism. With no Cu addition, the leaf chlorophyll, carotenoid, O2-, H2O2, and MDA contents of P. fortunei had no significant differences between the two acid rain treatments. However, with the addition of 100 and 200 mg Cu · kg-1, the chlorophyll and carotenoid contents of treatment pH 4.0 were lower, while the O2-, H2O2 and MDA contents were higher thanthose of treatment pH 5.0. The chlorophyll a/b ratio of treatments Cu was higher than that of the control. The leaf Cu content decreased obviously with the increasing acidity of stimulated acid rain, but the root Cu content was in reverse. With increasing Cu addition, both the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) and the total contents of phytochelatins (PCs) and glutathione (GSH) in treatment pH 5.0 increased, while the activities of SOD, POD, CAT and APX in treatment pH 4.0 decreased after an initial increase, and the total contents of glutathione (GSH) decreased greatly in treatment 200 mg Cu · kg-1. All of these demonstrated that the oxidative stress of high Cu concentration to P. fortunei was aggravated by stimulated acid rain. [ABSTRACT FROM AUTHOR]

In order to explore the changes in fracture mechanical properties of pipeline steel welded joints in hydrogen environment, the notched tensile in-situ hydrogen charging method was used to study the hydrogen embrittlement susceptibility of X80 steel base metal, welds and heat-affected zones under a total pressure of 12 MPa and a hydrogen partial pressure of 0.36 MPa. A high-pressure slow strain rate tensile testing machine was employed to conduct notch tensile test, and a high-pressure fracture toughness testing machine and a high-pressure corrosion fatigue testing machine were used to carry out fracture toughness and fatigue crack growth rate tests on X80 steel, respectively. The crack propagation behavior of X80 steel was studied by combining fracture toughness tests and fatigue crack propagation rate tests. Results showed that under the same conditions, compared with the base metal and heat-affected zone, the reduction of area at the weld position was significantly reduced, showing a higher susceptibility to hydrogen embrittlement. Compared with the original data in air at normal temperature and pressure, the crack tip opening displacement(CTOD) value of the weld position in the hydrogen partial pressure environment of 0.36 MPa changed slightly, and no secondary cracks appeared on the fracture surface. Compared with the air environment, the fatigue crack growth rate of X80 steel welds in a hydrogen partial pressure environment of 0.36 MPa increased by 1 order of magnitude, signifying that hydrogen could increase the fatigue crack growth rate of the material. However, according to the actual pipeline pressure fluctuation, the hydrogen embrittlement sensitivity of X80 steel was smaller under 0.36 MPa hydrogen partial pressure.

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]

A pot experiment was conducted to study the effects of simulated acid rain (pH 4.0, 5.0) and Cu (0-200 mg x kg(-1)) on the physiological characteristics of Paulownia fortunei and its detoxification mechanism. With no Cu addition, the leaf chlorophyll, carotenoid, O2 division by, H2O2, and MDA contents of P. fortunei had no significant differences between the two acid rain treatments. However, with the addition of 100 and 200 mg Cu x kg(-1), the chlorophyll and carotenoid contents of treatment pH 4.0 were lower, while the O2 divided by, H2O2 and MDA contents were higher thanthose of treatment pH 5.0. The chlorophyll a/b ratio of treatments Cu was higher than that of the control. The leaf Cu content decreased obviously with the increasing acidity of stimulated acid rain, but the root Cu content was in reverse. With increasing Cu addition, both the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) and the total contents of phytochelatins (PCs) and glutathione (GSH) in treatment pH 5.0 increased, while the activities of SOD, POD, CAT and APX in treatment pH 4.0 decreased after an initial increase, and the total contents of glutathione (GSH) decreased greatly in treatment 200 mg Cu x kg(-1). All of these demonstrated that the oxidative stress of high Cu concentration to P. fortunei was aggravated by stimulated acid rain.

Vegetation coverage is an important parameter in terrestrial ecological process, meteorological, and climatic models. By eliminating the errors from the precision of image classification and the noises of remote sensing images, and by using the actual data from fieldwork, this paper determined the maximum and minimum values of normalized difference vegetation index (NDVI), improved the sub-pixel model, and verified this model by calculating the vegetation coverage of Beijing. The results showed that the estimation value of the improved model was very close to the measurements, especially for the herbaceous plants whose vegetation types were the same but the densities were different. However, the estimation error of arborous vegetation coverage was relatively large, probably due to the effects of remote sensing image resolution, vegetation fragmentation, and mixed pixel model.

Sinocalycanthus chinensis is an endangered species in Sinocalycanthus, and only distributed in Zhejiang Province of China. This paper studied the photosynthetic responses of 2-year-old pot-cultured S. chinensis to different levels of water stress and temperature. The results indicated that under mild and moderate water stress, the net photosynthetic rate (Pn) of S. chinensis leaves was decreased to 92.3% and 74.3% of the control, respectively, which was mainly attributed to stomatal limitation; and under severe water stress, the Pn was decreased to 44.4% of the control, which might be mainly linked to non-stomatal limitation. The appropriate temperature for S. chinensis photosynthesis was from 20 degrees C to 28 degrees C. At 39 degrees C, the Pn, water use efficiency (WUE), and maximal photochemistry efficiency (Fv/Fm) were decreased significantly, while the dark respiration rate (Rd) and transpiration rate (Tr) were enhanced significantly. With increasing water stress and temperature, some photosynthetic parameters including light saturation point (LSP), apparent quantum yield (AQY) and maximal CO2 assimilation rate (Pmax) decreased to certain extents, while light compensation point (LCP) increased, suggesting that both severe water stress and higher temperature were the important environmental factors affecting the survival of S. chinensis.

Objective: To investigate the early diagnosis, treatment and prevention of pneumocystosis complicated after renal transplantation., Methods: Data from 12 cases of kidney transplant recipients who developed pneumocystosis were analyzed by clinical symptoms and signs, results of laboratory examination, imaging, bronchoscopy and biopsy. Combined TMP/SMZ was used for the prevention and treatment., Results: Pneumocystis carinii (Pc) detection rate was 16.7% from alveolar douche, 66.7% with bronchoscopy and biopsy. Two cases was diagnosed by PCR method with sputum. Plain chest film showed 58.3% of lung cirrhosis. CT showed 50% frosted glass-like change in lungs and 25% with lung consolidation. Eleven cases were cured but one died., Conclusion: Pc detection by bronchoscopy and biopsy, and PCR are most helpful in the diagnosis of pneumocystosis complicated with renal transplantation, in addition to plain chest film and CT scaning. Combined TMP/SMZ is effective in the prevention and treatment of pneumocystosis.