Search

Background To investigate the feasibility of the RegGAN model in image conversion for adaptive radiation therapy of the head and neck, and its stability under different models of CBCT.Methods 100 CBCT images and CT images of patients with head and neck tumors were used for training, and 40 patients were used for testing, Which the test set patients come from four different. linear accelerator The RegGAN model was used for training and testing. The image quality of the generated sCT (Synthetic-CT) was compared with that of pCT (Plan CT) using MAE (mean absolute error), PSNR (peak signal-to-noise ratio), and SSIM (structural similarity). Then, the same radiation therapy plan was used to perform PTV dose statistics on sCT and pCT, and the dose difference rate was calculated to further verify the accuracy of the model.Results The generated sCT had good image quality, and there was no significant difference among different CBCT mode. The conversion effect on Synergy was the best, and the MAE decreased from 231.3 ± 55.48 to 45.63 ± 10.78; PSNR increased from 19.40 ± 1.46 to 26.75 ± 1.32; SSIM increased from 0.82 ± 0.02 to 0.85 ± 0.04. The quality improvement effect of sCT image synthesis based on RegGAN is obvious, and there is no significant difference in sCT synthesis among different accelerators.Conclusion The sCT generated by the RegGAN model has high image quality, and the RegGAN model has high generalization ability among different accelerators, which can be used as a reference image for adaptive radiation therapy of the head and neck。

Porcine interferon α (poIFN-α) is a crucial cytokine that can prevent and treat viral infection. Seventeen functional porcine IFN-α subtypes were found in the porcine genome. In this study, multiple sequence alignment was performed to analyze IFN-α protein structure and function. Phylogenetic tree analysis of the porcine IFN gene family defined the evolutionary relationship of the various subtypes. Porcine IFN-αs, including porcine IFN-α1–17, were expressed in an E. coli expression system. The antiviral activities of these IFN-α proteins against vesicular stomatitis virus (VSV) and pseudorabies virus (PRV) were examined in PK-15 cells. We found that the antiviral activity of different porcine IFN-α molecules greatly differed: the porcine IFN-α14 and 17 subtypes had the greatest antiviral activities against VSV and PRV in PK-15 cells, porcine IFN-α1, 2, 3, and 8 exhibited lower biological activities, and porcine IFN-α4, 5, 6,7, 9, 10, 11, 12, 13, and 16 had minimal or no effect in the tested target cell‒virus systems. Moreover, our studies demonstrated that the antiviral activity of IFN-α was positively correlated with the induction of IFN-stimulated genes, such as 2’-5’ oligoadenylate synthetase 1 (OSA1), interferon-stimulated gene 15 (ISG15), myxoma resistance protein 1 (Mx1), and Protein kinase R (PKR). Thus, our experimental results provide important information for understanding the antiviral functions and mechanism of porcine IFN-α.

Radioactive material inspection in public is important to nuclear safety, and it is also the key security for holding large-scale events, while fast and efficient means of detecting radioactive materials are an important technical guarantee for nuclear safety. In this paper, energy and time distribution characteristics information of the natural background and target nuclide gamma particles are used to improve the sequential background comparison method. By using those energy and time distribution characteristics information, with the half-life and characteristic gamma-ray energy and branching ratio information of the nuclide, the response time and the identification accuracy of extremely low radioactive nuclides detected under natural-radiation background can be improved. Based on the theoretical research, the particle event acquisition device with the LaBr

Currently, the quantitative analysis methods for uranium that are widely used in laboratories, such as the volumetric method and inductively coupled plasma mass spectrometry (ICP-MS) cannot achieve low cost, simple operation, and little influence by other elements. The inductively coupled plasma optical emission spectrometer (ICP-OES) has a wide linear range, and high stability, and can be used to identify multiple elements simultaneously. However, when ICP-OES is used for quantitative analysis of uranium, the settings for the RF power, nebulizer flow, and pump rate can affect the analysis results. In this work, these parameters were carefully optimized for identifying uranium. Based on experiments, we selected two spectrum peaks 409.014 nm and 424.167 nm for quantitative analysis with the lowest interference. The optimal parameters obtained are atomizer flow rate of 0.75 L/min, a sample pumping rate of 1.6 mL/min, and a high-frequency power of 1400 W. Then we compared the accuracy of the volumetric method, ICP-MS method and ICP-OES method with the optimized parameter for analysis of experimental samples and references. The results showed that the ICP-OES with the optimized parameters proposed in this paper can be used to perform a convenient, quick, and efficient quantitative analysis of uranium in minerals.

The general sourceless efficiency calibration has two major methods, Monte Carlo simulation and numerical calculation. Monte Carlo simulation as an important method to address the efficiency calibration in complex measurement systems, despite it being highly accurate, but inefficient and time-consuming. And although the numerical calculation is computationally efficient, its accuracy is highly influenced by the multiple Compton scattering of rays in sensitive body, and it is difficult to deal with complex measurement systems. To solve the above problems, this paper proposes a discrete numerical calculation combined with the graphical Boolean operations method for sourceless efficiency calibration. The method starts with a Monte Carlo simulation to obtain the rays deposition process in an infinite sensitive body and record deposition locations as a matrix; then, for different measurement systems, discrete numerical calculations are used to rapidly obtain the transmission process of rays to the sensitive body of the detector; finally, the two are combined to obtain the detection efficiency of the rays by using graphical Boolean operations. For the given two test models, the error between the measured and calculated results of

Part weakly alkaline natural uranium-containing water contains abundant Ca2+ and (bi)carbonate. Herein, two kinds of materials, namely mesoporous hydrous manganese dioxide (MHMO) and polyacrylonitrile (PAN)/dolomite composites were synthesized and characterized to evaluate their adsorption behaviors of U(VI) from Ca2+ coexisted bicarbonate solution. Characterization results showed that both samples exhibited good structural stability after U(VI) load. MHMO could coordinate U(VI) through the surface –OH sites, whereas an unfavorable U(VI) adsorption onto mineral composites was deduced. Adsorption tests indicated that increasing Ca2+ and (bi)carbonate amounts suppress U(VI) adsorption process, and ∼19.0 mg/g U adsorbed by MHMO could be obtained in solutions with 1 mmol/L [Ca2+], 5 mmol/L [CO3]T, 50 mg/L [U(VI)]initial at pH 8.0. Moreover, a heterogeneous surface chemical adsorption was verified through kinetics and isotherms study. Results from our study should be useful in exploring the adsorption behaviors and mechanisms of U(VI) on selected inorganic and mineral materials from natural uranium-containing water.

This paper discusses an advanced spectral-ratio method that subtracts Compton scattering rays by using a Fast Fourier Transform rather than tripping ratios and establishes a new radon background estimation mathematical model. A ground model calibration technology and a non-radioactive calibration technology based on a multiple-step Monte Carlo simulation are proposed for determining the new calibration coefficients. Applying the new calibration coefficients by using the two calibration technologies, we can remove successfully from the U window. The relative standard deviation of the radon-corrected U window count between the two calibration technologies is less than 30% within the height of the airborne survey, and it is reduced as the height increases.

The Monte Carlo model of the nuclear emergency medical shelter was set according to the national standard. The absorbed dose of ICRU balls, on behalf of emergency personnel in the shelter, caused by major radionuclides (60Co, 85Kr, 131I, 133Xe, 137Cs) in the air around nuclear facilities was obtained by Monte Carlo simulation. The functional relationship between the maximum working time of emergency rescuers in the shelter and the activity concentration of radionuclide outside the shelter was given. Taking 137Cs as an example, the fitting curve of shielding lead layer quality and shielding effect was obtained according to the simulation result. When the thickness of the shielded lead layer reaches 5 mm, the working time of emergency rescuers in the shelter can be effectively improved from 1 hour to 2.5 hours under the activity concentration of 7.72E+09 Bq/m3.

Currently, the liquid scintillation method is widely used to measure the activity of tritiated water in the primary circuit of nuclear power plants, which leads to the continuous production of radioactive waste during measurement. In addition, the real-time activity information of tritiated water cannot be obtained. To solve this problem, herein we present an online tritiated water measurement method based on plastic scintillators that used the optical transport process in the Geant 4 software toolkit to build a model of plastic scintillation detection for tritiated water. Through simulation, the basic geometric dimensions of the detector were determined. In this dimension, using one detector to measure for 3 h, when the tritiated water activity was 100 Bq/L, its resolution was 16% (16 Bq/L). In addition, calculations were performed for the presence of other background signals to obtain the minimum detectable concentration.

Antifungal drugs have already been established as an effective treatment option for Candida parapsilosis infections, but there is no universal consensus on the ideal target for clinical efficacy and safety of antifungal drugs for the treatment of C. parapsilosis infections. Few studies have directly compared the efficacies of antifungal drugs for the treatment of C. parapsilosis infections. We hypothesize that different antifungal drugs offer differing clinical efficacy and safety for the treatment of C. parapsilosis infections. We performed a comprehensive network meta-analysis on different strategies for C. parapsilosis infection treatment and compared the clinical efficacy and safety of antifungal drugs as interventions for C. parapsilosis infections. The Cochrane Database of Systematic Reviews, Medline, Embase, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), Technology of Chongqing VIP database, Wan Fang Data, and SinoMed databases were searched to identify appropriate randomized trials. Among the extracted C. parapsilosis cases, the survival and death rates with treatment of C. parapsilosis infection were compared among groups treated with different antifungal drugs. According to the evidence-network analysis, echinocandins were a better choice than other drugs for treating C. parapsilosis infections, and more importantly, caspofungin showed a more preferable effect for decreasing the risk of 30 day mortality. In conclusion, this study systematically evaluated the effectiveness and safety of antifungal drugs for the purpose of helping clinicians choose the most appropriate antifungal drugs. Future studies with larger samples are needed to evaluate the effects of patient factors on the clinical efficacy and safety of antifungal drugs for C. parapsilosis infections.

In this study, the theory of minimum detectable activity concentration (MDAC) for airborne gamma-ray spectrometry (AGS) was derived, and the relationship between the MDAC and the intrinsic efficiency of a scintillation counter, volume, and energy resolution of scintillation crystals, and flight altitude of an aircraft was investigated. To verify this theory, experimental devices based on NaI and CeBr3 scintillation counters were prepared, and the potassium, uranium, and thorium contents in calibration pads obtained via the stripping ratio method and theory were compared. The MDACs of AGS under different conditions were calculated and analyzed using the proposed theory and the Monte Carlo method. The relative errors found via a comparison of the experimental and theoretical results were less than 4%. The theory of MDAC can guide the work of AGS in probing areas with low radioactivity.

The grounding switch is an important component to ensure safety on its GIS and maintenance personal. In this paper, the COMSOL Multiphysics software is used to carry out electrostatic field analysis on grounding switch in GIS by the finite element method. This study also did a lot of research including drawing 3D models of key parts, gridding division and post-processing the data of electric field. The field intensity distribution diagrams and the maximum value of field intensity concentration area of key insulation position at 1100kV and 500kV are obtained. The electric field intensity distribution of GIS near the static contactor of the grounding switch is discussed, and the design of appropriately increasing the radius of the conductor in the part the great abrasion is proposed, and it provides a theoretical basis for the electric field distribution of electrical equipment.

It is important to employ multi-physics coupling strategy in thermal-hydraulics/safety analysis of nuclear reactors. In general, it is based on couplings of system codes with neutron dynamics codes, which is incompetent to cope with multi-dimensional thermal-hydraulics/safety problems involved in liquid metal cooled pool-type reactors. To cope with it, Computational Fluid Dynamics tools are good choices which have attracted considerable attentions in reactor simulation these years. In order to apply a commercial CFD program in thermal-hydraulics/safety analyses, the research on couplings of Point Kinetics (PK) model and a fuel pin Heat Conduction (HC) model to the commercial CFD platform FLUENT abbreviated as HC-PK-CFD is performed in this study. Verifications are performed by the benchmark simulation on beam interruption transients for an accelerator-driven sub-critical reactor system. It is demonstrated that the results simulated by HC-PK-CFD agrees well with the ones by other ten multi-physics coupling codes participating in this benchmark.

Radioactive source localization algorithms have been widely used in the detection of nuclear accident areas. But some shortcomings, such as complex algorithm structure, slow localization speed and poor accuracy, were obviously performed to affect mobile robot locating autonomously. In this paper, a potential alternative method was investigated to be a new usage of locating leaks, just via specifying the change of exposure rate. In this model, several key factors, such as gamma ray attenuation, scattering factor, travel angle guide, spatial discretization, etc., were taken into consideration, to demonstrate the effectiveness of the algorithm, which is appropriated in unknown areas of the radioactive waste repository. Since there are three factors with different contribution, such as position, quantity of the source and gamma ray energy, which considered to demonstrate its impact on success. So, a hybrid adaptive grey wolf algorithm (HAGWO) has been adopted and implemented to develop a novel rapid method of radioactive leak location. Three aspects, including the good point set initialization in population size, balanced convergence function, and self-adaptive greedy strategy for population update, were optimized and merged into the locating model. To investigate the effectiveness of the algorithm, results of HAGWO are compared with grey wolf algorithm (GWO), good point set initialization strategy GWO(GGWO) and adaptive head wolf strategy GWO (ALGWO) in convergence speed, accuracy, stability and positioning error of single and double leak points. It is observed that convergence speed is increased by 37.93 ± 2% at the highest; the convergence accuracy is increased by 92.42 ± 2% at the most; the stability is improved by 30% ∼ 50%. The positioning error of single leak point is within 1.08%, and the positioning error of double leak point is less than 8.90%. Besides, compared with GWO, GGWO and ALGWO, the single-point accuracy is improved by 1.36 percentage points (to GWO), and the double-point accuracy is improved by 40.35 percentage points (to ALGWO) at most. It is observed that HAGWO performs the best in locating leaks, with a faster convergence, stronger stability and more accuracy.

Baseline correction is an important step in energy-dispersive X-ray fluorescence analysis. The asymmetric least squares method (AsLS), adaptive iteratively reweighted penalized least squares method (airPLS), and asymmetrically reweighted penalized least squares method (arPLS) are widely used to automatically select the data points for the baseline. Considering the parametric sensitivity of the aforementioned methods and the statistical characteristics of the X-ray energy spectrum, this paper proposes an asymmetrically reweighted penalized least squares method based on the Poisson distribution (PD-AsLS) to automatically correct the baseline of X-ray spectra. Monte Carlo (MC) simulation is used to obtain the background spectrum, and PD-AsLS is used to estimate the baseline of the background. The relative error and the absolute error between the simulated background and PD-AsLS estimated background are used to determine the accuracy of PD-AsLS. The correlation coefficient (COR) and the root mean square error (RMSE) between the estmated baseline and the real baseline are calculated, and results of PD-AsLS are compared with results of three other classical methods (arPLS, airPLS and AsLS) to evaluate the reliability of PD-AsLS. The results of PD-AsLS show that the COR is above 0.95 and RMSE is less than 6. The stability and the practicability of PD-AsLS are also evaluated in experiments. A sample is measured five time to get its X-ray energy spectra, and the coefficient of variation (CV) of the estimated baseline is smaller than that of measured spectra. Experiments show that PD-AsLS can estimate baselines better than arPLS without any overestimation. Those results indicate that PD-AsLS can reliably estimate the baselines of X-ray spectra and effectively suppress the statistical fluctuation.

To perform an integral simulation of a pool-type reactor using CFD code, a multi-physics coupled code MPC-LBE for an LBE-cooled reactor was proposed by integrating a point kinetics model and a fuel pin heat transfer model into self-developed CFD code. For code verification, a code-to-code comparison was employed to validate the CFD code. Furthermore, a typical BT transient benchmark on the LBE-cooled XADS reactor was selected for verification in terms of the integral or system performance. Based on the verification results, it was demonstrated that the MPC-LBE coupled code can perform thermal-hydraulics or safety analyses for analysis for processes involved in LBE-cooled pool-type reactors.

Thermoluminescence (TL) dating is one of the most significant chronological tools used in Quaternary research. However, for changes in the characteristics of quartz, the larger deviation is still a problem in TL dating, especially with the single-aliquot regeneration-does (SAR) procedure. In the SAR-TL protocol, changes in the characteristics of quartz inevitably cause a shift in the TL peak position and a reduction in the sensitivity of the TL peak during repetitive thermal treatment. In this paper, we studied the optimal TL parameters to minimize the effect of the above problems for TL dating. Based on the optimization experiment combining OSL and TL measurements, the optimal preheat temperature was found to be 300 °C for both silt-sized grains and sand-sized grains, which eliminates the remainder of the 325 °C TL signals and inhibits the 375 °C TL peak position shift. Referring to the test does in SAR-OSL dating protocol, the optimal test doses, 200 Gy and 250 Gy for the silt-sized grains and sand-sized grains respectively, were determined to correct the reduction in TL sensitivity, and they were added to improve the SAR-TL protocol. The improved SAR-TL protocol with the optimal measurement parameters, which we called the accurate-parametric SAR-TL protocol, improves the accuracy of quartz TL dating and expands the range of accurate TL dating. For the experimental doses of 400 Gy and 700 Gy, the relative error of D

The sensitivity calculation of airborne gamma-ray spectrometer (AGS) is usually performed by on-ground or in-flight calibration. However, both methods are cost-ineffective or not permissive, especially for artificial radioisotopes with short half-lives. Alternative to these methods is the Monte Carlo simulation, which has been widely applied over the last few decades. The greatest challenge to the practicability of the Monte Carlo simulation in the AGS calibration is its low computational efficiency for ensuring an acceptable reliability. This article proposes a hybrid numerical method for the sourceless AGS calibration by combining the deterministic point-kernel approach and the Monte Carlo simulation. This method is not only more efficient than the source-based calibration by an empirical method, but also independent of the source availability for on-ground or in-flight calibration. For a given soil test model, AGS sensitivities calculated by this hybrid method agree well with those obtained from the empirical method for the in-flight calibration.

A measuring circuit is designed based on the transimpedance amplifier. The methods of reducing parasitic capacitance and improving amplifier performance are introduced in detail. The influence of the parasitic capacitance generated by the feedback resistors on the bandwidth in the transimpedance amplification circuit is discussed. The circuit can measure the wide-dynamic-range low current ranging from 10-13 A to 10-5 A in four ranges. The circuit's bandwidth is up to 500 Hz when the circuit can normally work to measure a wide-range low current. The peak-to-peak amplitude of circuit noise is less than 0.22 pA. The current drift is less than 1.06 fA/∘C over a temperature range of 0∘C to 85∘C, and the integral nonlinearity is less than 0.25%.

Since the baseline of the unipolar pulse shaper have the direct-current (DC) offset and drift, an additional baseline estimator is need to obtain baseline values in real-time. The bipolar zero-area (BZA) pulse shapers can be used for baseline restoration, but they cannot restrain the baseline drift due to their asymmetrical shape. In this study, three trapezoids are synthesized as a symmetrical zero-area (SZA) shape, which can remove the DC offset and restrain the baseline drift. This baseline restoration technique can be easily implemented in digital pulse processing (DPP) systems base on the recursive algorithm. To strengthen our approach, the iron's characteristic x-ray was detected using a Si-PIN diode detector. Compared with traditional trapezoidal pulse shapers, the SZA trapezoidal pulse shaper improved the energy resolution from 237 eV to 216 eV for the 6.403 keV Kα peak.

The full-spectrum least-squares (FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid samples. Based on the conventional least-squares principle, this spectrum evaluation method is able to obtain the background-corrected and interference-free net peaks, which is significant for quantization analyses. A variety of analytical parameters and functions to describe the features of the fluorescence spectra of pure elements are used and established, such as the mass absorption coefficient, the $$G_{i}$$ factor, and fundamental fluorescence formulas. The FSLS iterative program was compiled in the C language. The content of each component should reach the convergence criterion at the end of the calculations. After a basic theory analysis and experimental preparation, 13 national standard soil samples were detected using a spectrometer to test the feasibility of using the algorithm. The results show that the calculated contents of Ti, Fe, Ni, Cu, and Zn have the same changing tendency as the corresponding standard content in the 13 reference samples. Accuracies of 0.35% and 14.03% are obtained, respectively, for Fe and Ti, whose standard concentrations are 8.82% and 0.578%, respectively. However, the calculated results of trace elements (only tens of μg/g) deviate from the standard values. This may be because of measurement accuracy and mutual effects between the elements.

Cetyltrimethylammonium bromide modified hydroxyapatite-bentonite composites (CTAB-HAp-Bent) were first synthesized by one-step hydrothermal method to test its U(VI) adsorption behaviors from phosphate‑carbonate coexisted solution. When pH = 8.0, U(VI) = 50 mg/L, [CO3]T = 2 mmol/L, and [P] = 1.5 μmol/L, CTAB-HAp-Bent achieved the maximum qe values ~108.19 mg/g compared to HAp-Bent (~40.62 mg/g), CTAB-Bent (~81.70 mg/g) and HAp (93.90 mg/g). High alkalinity and ionic strength were unfavorable for U(VI) adsorption. Specifically, qe values increased with an increase of [P] up to 500 μmol/L and then changed little in the ranges from 500 μmol/L to 2000 μmol/L, whereas carbonate suppressed U(VI) adsorption in the whole studied [CO3]T. Pseudo-second-order model, Langmuir isotherm and the thermodynamics deduced a spontaneous endothermic monolayer surface chemical adsorption process. Besides, characterization results suggested that the adsorption mechanisms were involved in the Br− anion exchange and -OH group coordination. Our present work optimized the U(VI) adsorption capacity of bentonite in eutrophic carbonate water, benefiting the research and design of potential modified clay or clay minerals materials for uranium recovery from eutrophic natural uranium-containing water.

Point kinetics equations (PKEs) is an significant model used to describe dynamic behaviors of neutron in nuclear reactors. How to cope with its stiffness problems is very important to solve PKEs accurately and efficiently. In this paper, a new semi-analytical algorithm based on Euler-Maclaurin Approximation (SAEMA) is developed to solve PKEs. SAEMA algorithm is applied and tested in different reactors with three typical reactivity insertion cases, including step, ramp and sinusoidal insertions. Firstly, the investigations on the computational stability are performed under different time step sizes. Secondly, the performances on computational accuracy are evaluated by comparing the results by SAEMA algorithm with the ones by analytical method and excellent CATS algorithm. Finally, by comparing the CPU time consumed by SAEMA algorithm with the physical time, the studies on the computational efficiency are also carried out. Just as results shows, SAEMA algorithm is reasonably an attractive way to solve the PKEs.

Identification method research on ore-caused anomalies information is one of the core technologies of airborne gamma-ray spectrum data post-processing. This paper proposed a decomposition and reconstruction method of anomaly information called fractal singular value decomposition (FSVD), aiming at the current ubiquitous truncation error and boundary effect problems in filter design in ore-caused anomaly information identification methods in airborne gamma-ray spectrum. Based on the multi-fractal theory, this method decomposes the singular value of the specific nucleus activity data of the airborne gamma-ray spectrum under time series, and quantitatively calculates the fractal singular value truncation parameter according to residual square sum minimum principle. According to the calculation result, the original data is partially reconstructed to rebuild the ore-caused anomalies information. This paper used the 1:50000 airborne gamma-ray spectrum trial production flight data of a certain area in Inner Mongolia (the surveying area contains proved metal ore occurrences) to verify the method. The results show that: after the original signals are decomposed by FSVD, the high, medium and low singular values can represent the background, anomaly, and noise signal, respectively. At the same time, the false anomaly signals caused by flight error exist in high singular values. After reconstructing the decomposed signals according to median singular values, background noises can be effectively separated, the ore-caused anomaly in the known ore-caused anomalies can be identified and band-like false anomalies caused by time domain batches can be removed.

Based on the geochemical prospecting data, we have calculated the gamma absorbed dose rates in air 1 m above the ground surface in the Chengdu Plain, analyzed the relationship between the geological conditions and the distribution of the natural radionuclides, and preliminarily studied the influence of the geological conditions on the terrestrial radiation level in the Chengdu Plain. The result shows that the terrestrial radiation level in the Chengdu Plain is slightly lower than the average values of China and varies greatly according to the complex geological conditions.

Background: Tacrolimus has been reported to be effective in refractory nephrotic syndrome, such as focal segmental glomerulosclerosis and membranous nephropathy. Some IgA nephropathy (IgAN) patients with massive proteinuria showed resistance to steroids and/or cytotoxic immunosuppressants based on the supportive therapy with renin- angiotensin system blockade. The efficacy and safety of tacrolimus in such refractory IgAN patients are extremely ambiguous, and the mechanism of tacrolimus improving proteinuria remission needs to be investigated. Methods: 14 refractory IgAN patients were enrolled. The patients received tacrolimus (0.05–0.1 mg/kg/day) and prednisone (0.5 mg/kg/day) for at least 6 months. Synaptopodin and calcineurin expression were detected in renal tissues of patients who received re-biopsy. A puromycin aminonucleoside (PAN)-induced human podocyte injury model was applied to investigate the possible role of tacrolimus in proteinuria remission. Results: Of the 14 patients enrolled, 3 were withdrawn because serum creatinine increased over 30% baseline. In 11 patients treated with tacrolimus over 6 months, 9 showed complete or partial remission and 7 achieved remission within 1 month. In renal tissues, the expression of calcineurin increased while synaptopodin decreased and recovered partially after tacrolimus therapy. In an in vitro study, F-actin disrupted in human podocytes after stimulation of PAN, while calcineurin increased and synaptopodin decreased. After co-treatment with tacrolimus the reorganization of F-actin and the expression of calcineurin and synaptopodin recovered. Conclusions: Tacrolimus showed a rapid proteinuria remission in refractory IgAN patients. The possible mechanism of tacrolimus to proteinuria remission might be podocyte cytoskeleton stabilization through inhibition of calcineurin expression.

This paper discusses a new method of background estimation in the energy-dispersive X-ray fluorescence (EDXRF) analysis, which is based on Fourier Transform (in this paper, we call it Fourier Transform background estimation method). Compared with the Sensitive Nonlinear Iterative Peak method, the new method has the feature of FWHM independence. It has been proved that a background can be estimated automatically and accurately by the new method in the synthesized spectrum and the spectra from measurement. Fourier Transform background estimation method can estimate the background accurately in the EDXRF spectrum using an X-ray tube source. Copyright © 2011 John Wiley & Sons, Ltd.