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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 48-53, 2017 01.
Artigo em Zh | MEDLINE | ID: mdl-30192467

RESUMO

CO(2) retrievals with high quality facilitate resolving the sources and sinks of CO(2) are helpful in predicting the trend in climate change and understanding the global carbon cycle. Based on a nonlinear least squares spectral fitting algorithm, we investigate the optimization method for CO2 products derived from ground-based high resolution Fourier transform infrared spectra. The CO(2) vertical column densities (VCDs) are converted into column-averaged dry air mole fraction XCO(2) by using the fitted O(2) VCDs, and thus the system errors (e. g. pointing errors, ILS errors, zero-level offset) are corrected greatly. The virtual daily variation which is related to air mass factor is corrected with an empirical model. The spectra screening rule proposed in this paper can greatly improve the XCO2 quality. The CO(2) retrievals before and after the optimized method are compared using a typical CO(2) daily time series. After using the optimized method, the fitting error is reduced by 60%, and the two-hours-averaged precision is ~0.071% (equals to ~0.28 ppm), which is perfectly in line with the TCCON (the total carbon column observing network) threshold, i. e., less than 0.1%.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 2725-31, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-30084585

RESUMO

Ring effect is defined as the phenomenon that the depth of solar Fraunhofer lines in scattered light is less than those observed in direct sunlight. The aerosol could change the light path and the scattering properties in the atmospheric, and influence Raman Scattering Possibility of the photons, and finally affect the filling-up effect. Aerosol parameters (aerosol optical depth, boundary layer height, single scattering albedo, asymmetric factor) could be obtained by observation of the Ring effect in different aerosol condition. The Ring effect is measured by ground-based MAX-DOAS instrument under clear days and the measurement results is compared with McAritim results. The comparison has a good agreement. Radiation transfer model McArtim is used to study the sensitivity of the Ring effect to the aerosol parameters. The study shows that in most conditions, aerosol optical depth (AOD) and boundary layer (bh) height has a great influence to RSP, and in 90 degree elevation angle, RSP has a decrease of 24.6% when AOD varies from 0.1 to 1, and a decrease of 4.4% when bh varies from 1km to 3 km. The study shows RSP is more sensitive to AOD and boundary layer height, which may provide a new method for aerosol profile.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(12): 3381-4, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23427572

RESUMO

Using photodiode array (PDA) detector and spectrometer, a method on the basis of algorithm of nondispersive ultraviolet (NDUV) is described to measure and analyze nitric oxide (NO) gas. With the introduction of light source impact factor and absorption spectrum impact factor, fitting equation and correlation coefficient between absorbance and concentration was acquired through comparative analysis on the total intensity of nitric oxide absorption and non-absorption spectrum, which are collected in different integration times and within different wavelength width. The results show that second order fitting correlation coefficient related to absorbance and concentration is above 0.999 9 and the error of concentrations between the concentration calculated by fitting equation and the standard concentration is less than 3% through using suitable fitting order, fitting wavelength width and analysis method.

4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(11): 2950-5, 2012 Nov.
Artigo em Zh | MEDLINE | ID: mdl-23387156

RESUMO

The cloud effect correction is very significant to satellite remote sensing of atmospheric trace gases from near-infrared spectrum, even with a small amount of cloud, the remaining effects can still cause retrieval error even reaching up to 100%. Atmospheric carbon monoxide (CO) is one of the most important pollutants in the troposphere. This study, takeing CO as the example, described the cloud effect and the cloud correction on retrieval result from SCIAMACHY measurement. To validate the correction method, we compared both corrected and uncorrected results with the independent ground based FTIR measurements. After the correction, the agreement between satellite observations and FTIR measurements further improves.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(10): 2719-24, 2011 Oct.
Artigo em Zh | MEDLINE | ID: mdl-22250543

RESUMO

A method of interference correction for nondispersive infrared multi-component gas analysis was described. According to the successive integral gas absorption models and methods, the influence of temperature and air pressure on the integral line strengths and linetype was considered, and based on Lorentz detuning linetypes, the absorption cross sections and response coefficients of H2O, CO2, CO, and NO on each filter channel were obtained. The four dimension linear regression equations for interference correction were established by response coefficients, the absorption cross interference was corrected by solving the multi-dimensional linear regression equations, and after interference correction, the pure absorbance signal on each filter channel was only controlled by the corresponding target gas concentration. When the sample cell was filled with gas mixture with a certain concentration proportion of CO, NO and CO2, the pure absorbance after interference correction was used for concentration inversion, the inversion concentration error for CO2 is 2.0%, the inversion concentration error for CO is 1.6%, and the inversion concentration error for NO is 1.7%. Both the theory and experiment prove that the interference correction method proposed for NDIR multi-component gas analysis is feasible.

6.
World J Urol ; 27(3): 385-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19082604

RESUMO

OBJECTIVES: We assessed the feasibility of extraperitoneal laparoscopic prostatectomy in pilots in China. MATERIALS AND METHODS: Extraperitoneal laparoscopic retropubic prostatectomy has been performed in 45 patients with prostatic weight more than 60 g between May 2005 and May 2008. The laparoscopic approach was standard in all cases as follows: creation of a preperitoneal workspace, haemostatic control of lateral venous vesicoprostatic pedicles, transversal anterior incision of the prostate capsule, prostatic adenomectomy and retrieval of the specimen. RESULTS: The average prostate resected weight was 78.2 +/- 16.3 g. Mean operative time was 105.4 +/- 26.5 min. Conversion to open prostatectomy was not required. The transfusion was essential in three cases. During a 6 months follow-up period for 40 cases, the mean score of IPSS decreased from 25.5 +/- 2.4 to 6.2 +/- 2.1, Q(max) increased from 6.1 +/- 2.8 to 18.7 +/- 3.4 ml/s. None of the patients presented with urinary incontinence. CONCLUSIONS: In our experience, laparoscopic extraperitoneal adenomectomy (Millin's procedure) is feasible with minimal invasion and is a simple straightforward technique.


Assuntos
Laparoscopia , Prostatectomia/métodos , Hiperplasia Prostática/cirurgia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade
7.
Zhonghua Nan Ke Xue ; 13(5): 440-3, 2007 May.
Artigo em Zh | MEDLINE | ID: mdl-17569263

RESUMO

OBJECTIVE: To inhibit the expression of connexin43 (Cx43) in the human corpus cavernosum penis smooth muscle cells by small interfering RNA (siRNA) and detect the gap junction intercellular communication (GJIC), and to investigate the application of siRNA technology in the gap junction of corpus cavernosum penis smooth muscle cells and its role in the penile erection process. METHODS: With the help of the software of Ambion Corporation, the specific recombinant plasmids with siRNA targeting human Cx43 gene were constructed. The recombinant plasmids having been stably transferred into human corpus cavernosum penis smooth muscle cells for 48 hours, semi-quantitive reverse transcription polymerase chain reaction (RT-PCR) and Western blotting techniques were used to examine the inhibitory effects of siRNA on the expressions of the Cx43 gene and protein, in comparison with the siRNA negative control and the blank control group, respectively. The GJIC was detected by scrape-loading and fluorescence dye transfer experiments through the fluorescence microscope. RESULTS: The results of enzyme digestion analysis and DNA sequencing showed that the recombinant plasmid pSilencer 1.0-U6-siRNA-Cx43 was successfully constructed. The relative levels of Cx43 mRNA and protein expression in the smooth muscle cells were (0.45 +/- 0.08)% and (0.56 +/- 0.06)% after successful transfer of the recombinant plasmid. However, the expression levels of mRNA and protein were (0.72 +/- 0.04)% and (0.80 +/- 0.08)% in the negative siRNA transfer group, and (0.74 +/- 0.09)% and (0.77 +/- 0.11)% in the blank control, respectively, with a significant difference (P < 0.05). The GJIC also decreased significantly. CONCLUSION: siRNA can significantly inhibit the expression of Cx43 and block the GJIC in the human corpus cavernosum penis smooth muscle cells. siRNA technology plays an important role in penile erection and flaccidity.


Assuntos
Conexina 43/biossíntese , Miócitos de Músculo Liso/fisiologia , Pênis/metabolismo , RNA Interferente Pequeno , Northern Blotting , Células Cultivadas , Conexina 43/genética , Humanos , Junções Intercelulares , Masculino , Pênis/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
8.
J Endourol ; 28(3): 353-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24229434

RESUMO

PURPOSE: To compare the performance of voluminous benign prostatic hyperplasia patients who have received laparoscopic simple prostatectomy (LSP) with the patients who have received bipolar transurethral resection of the prostate (B-TURP) in their perioperative and 3-year follow-up period. METHODS: Ninety patients with prostate volumes >80 mL (range 80-130 mL) were randomly assigned to either LSP or B-TURP surgery type. The patients were followed up at 1, 3, 6, 12, 24, and 36 months postoperatively. Perioperative and follow-up characteristics were then recorded and compared. RESULTS: More blood loss, greater resected adenoma volume, and shorter catheterization duration were recorded in LSP group than that of B-TURP group (140.1±81.5 vs 93.1±54.0 mL; 65.3±13.8 vs 49.0±12.7 mL; 3.3±1.2 vs 3.8±1.0 days; p<0.05). None of the patients in LSP group reported complications out of 30 days, while 1 case of urethral stricture, 36 cases of retrograde ejaculation, 1 case of bladder neck contracture, and 2 cases of recurrence were recorded in B-TURP group. At 1, 3, 6, and 12 months postoperatively, there were no significant differences in terms of postvoid residual urine volume, maximal urinary flow rate (Qmax), and International Prostate Symptom Score between the two groups (p>0.05). In contrast, the differences became significant at 24 and 36 months (p<0.05). CONCLUSIONS: Compared with B-TURP, LSP with Madigan technique is accompanied by less residual adenoma, shorter catheterization time, and more blood loss. Further, the risk of late complications is lower with LSP and, in terms of functional outcomes, LSP appears to be better than B-TURP beyond 2 years.


Assuntos
Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata/métodos , Micção/fisiologia , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Seguimentos , Humanos , Incidência , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/fisiopatologia , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/fisiopatologia , Estudos Retrospectivos , Fatores de Tempo , Ressecção Transuretral da Próstata/efeitos adversos , Resultado do Tratamento
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