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1.
Int Ophthalmol ; 43(12): 4435-4441, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37804368

RESUMO

PURPOSE: To investigate the distribution of ultrasound cyclo plasty (UCP) probe models in Chinese patients with glaucoma. METHODS: Patients needing glaucoma surgery were recruited at Zhongshan Ophthalmic Center from January 2019 to December 2019. Patient demographics were recorded and analyzed. Visual acuity, intraocular pressure (IOP), retinal nerve fiber layer (RNFL), mean defect of visual field (MD), ocular axial length (AL) and horizontal corneal diameter (white to white, WTW) of eyes with glaucoma were measured. In addition, the UCP probe models were calculated using a nomogram tool and two ocular anatomical parameters: WTW and AL. RESULTS: A total of 1281 patients (2000 eyes) were included in the study, including 559 males (43.64%) and 722 females (56.36%). The age of the patients ranged from 18 to 91 years, with a mean age of 61.43 ± 12.21 years. IOP ranged from 22.0 to 60.0 mmHg, with a mean of 26.17 ± 3.52 mmHg. The mean AL and WTW were 22.96 ± 1.43 (ranging from 19.07 to 35.00) and 11.55 ± 0.50 (ranging from 9.6 to 13.7), respectively. According to the results calculated by the nomogram tool, Chinese patients' eyes mainly adapted to Model 12, with a percentage of 69.05%. Model 13 and Model 11 were suitable for 26.65% and 3.35% of the patients, respectively. A total of 0.95% of Chinese patients did not have a suitable probe model. CONCLUSION: For Chinese patients who needed glaucoma surgery, UCP probe models were mainly attributed to Model 12, followed by Model 13, and Model 11 was the least used.


Assuntos
Glaucoma , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Adolescente , Adulto Jovem , Adulto , Idoso de 80 Anos ou mais , Glaucoma/diagnóstico , Glaucoma/cirurgia , Pressão Intraocular , Tonometria Ocular , Retina , China/epidemiologia
2.
Environ Sci Pollut Res Int ; 30(27): 71063-71087, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37156950

RESUMO

Accurate prediction of carbon emissions is vital to achieving carbon neutrality, which is one of the major goals of the global effort to protect the ecological environment. However, due to the high complexity and volatility of carbon emission time series, it is hard to forecast carbon emissions effectively. This research offers a novel decomposition-ensemble framework for multi-step prediction of short-term carbon emissions. The proposed framework involves three main steps: (i) data decomposition. A secondary decomposition method, which is a combination of empirical wavelet transform (EWT) and variational modal decomposition (VMD), is used to process the original data. (ii) Prediction and selection: ten models are used to forecast the processed data. Then, neighborhood mutual information (NMI) is used to select suitable sub-models from candidate models. (iii) Stacking ensemble: the stacking ensemble learning method is innovatively introduced to integrate the selected sub-models and output the final prediction results. For illustration and verification, the carbon emissions of three representative EU countries are used as our sample data. The empirical results show that the proposed framework is superior to other benchmark models in predictions 1, 15, and 30 steps ahead, with the mean absolute percentage error (MAPE) of the proposed framework being as low as 5.4475% in Italy dataset, 7.3159% in France dataset, and 8.6821% in Germany dataset.


Assuntos
Meio Ambiente , Análise de Ondaletas , Previsões , Fatores de Tempo , França
3.
Front Med (Lausanne) ; 8: 715747, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34458290

RESUMO

Aim: The aim of this study was to investigate the changes in anterior segment parameters as assessed by ultrasound biomicroscopy (UBM) after laser peripheral iridotomy (LPI) and to propose a prediction equation for the width of the angle after LPI. Design: This was a prospective study. Participants: The participants included 100 subjects with primary angle closure suspect (PACS). Methods: Anterior segment UBM parameters were measured, whereas AOD750 was chosen to indicate the width of the angle associated with gonioscopic angle closure, as found in a prior study. Main Outcome Measures: Angle parameters, iris parameters, anterior chamber parameters and ciliary body parameters. Results: All angle parameters increased after LPI, including the mean angle opening distance at 750 µm (AOD750), mean angle opening distance at 500 µm from the scleral spur (AOD500), mean angle opening distance at 750 µm from the scleral spur (AOD750), and mean angle recess area at 750 µm from the scleral spur (ARA750). Among iris parameters and ciliary body parameters, the iris thickness at 2,000 µm (IT2000), iris curvature (IC), and trabecular-ciliary process distance (ICPD) were reduced after LPI. The final equation consisted of four parameters: anterior chamber depth (ACD), iris thickness at 750 µm from the scleral spur (IT750), AOD750, and lens vault (LV). This equation explained 42.7% of the variability in the angle opening indicator AOD750 after LPI, whereas in the plateau iris configuration subgroup, the accuracy of the prediction equation reached the highest a maximum of 68.6%. Conclusions: There was an increase in angle opening and iris flattening after LPI. An equation involving four angle parameters was constructed, this equation which could explained 42.7% of the variability in the angle opening indicator AOD750 after LPI whereas in the plateau iris configuration subgroup, the accuracy of the prediction equation reached a maximum of 68.6%.

4.
Appl Opt ; 58(6): 1537-1546, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30874044

RESUMO

L625 4-wavelength dual Raman-Mie lidar was used to detect elastically Mie backscattered light at emitting wavelengths (532 and 355 nm) emitted by one Nd:YAG laser, and the nitrogen Raman light (607 and 386 nm) inelastically backscattered by nitrogen molecules at Hefei (117.3°E, 31.9°N), China from 2007 to 2013. From the four return signal profiles, highly accurate aerosol extinction and backscatter coefficients, lidar ratio, Ångström exponent, and aerosol Junge exponent can be determined. Furthermore, with a priori assumption of the real part of complex refractive index nr=1.50, the profiles of more aerosol microphysical parameters can be retrieved with their respective errors in the free troposphere, such as the imaginary part of the refractive index, Junge number density coefficient, and particle mass index. The profiles of aerosol microphysical parameters were obtained for 179 nights. Their variation and statistical features were discussed.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(4): 834-8, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18619310

RESUMO

Without the hypothesis of atmospheric parameters and auxiliary equipment, it is proven the slope method is capable of deriving extinction coefficients profiles and atmosphere optical depth through the analysis of the atmospheric environment detecting airborne lidar (AEDAL) data collected during November 7 to 11, 2005. The spatial and temporal variations of the planet boundary layer (PBL), aerosol optical depth (AOD) of the PBL and aerosol distribution along flight lines are exhibited from the AEDAL inversion results. Firstly, the sinking of aerosol was found in Yellow Sea area, moreover, the PBL altitude also dropped while the multi-layer aerosol presented after a cold front passage; secondly, the AOD of the PBL is the highest over Qingdao city, the lowest over foothill area and in between them over sea area, Meanwhile, it is relatively stable over sea area but slightly increases nearby upslope. The AOD values of the PBL were determined to be 0.15-0.35 in clear day and 0.3-0.45 in foggy day over the area from Qingdao to Bohai, but they are higher and reach around 0.55 in Yellow Sea area. It is evidenced that the aerosol in the PBL mainly comes from city and also is contributed by salt sea over Qingdao area, and ridge and surface wind play an important role in the aerosol transport while the monsoon affects the aerosol distribution.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Aerossóis/química , Calibragem , China , Oceanos e Mares
6.
Huan Jing Ke Xue ; 29(3): 562-8, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18649508

RESUMO

The parameters of AML-2 mobile lidar were introduced, which was based on differential absorption principle and designed by our institute. In Yufa of Beijing, the pollutants including O3, NO2, SO2 in atmospheric boundary layer were monitored in August and September of 2006 under different weather conditions. Vertical profile and diurnal variation of concentrations of these pollutants were analyzed. If without the influence of pollution air transport from south region, the concentrations of these pollutants are low under the overcast weather condition. The concentrations of O3 and NO2 decrease with altitude, and this characteristic is not obvious for SO2, but there is a high concentration layer of SO2 near ground (about 0.6km). The quality of atmosphere Beijing is influenced significantly by air transportation from south region, and the altitude of the severe pollution air transport is about 1km to 1.5km in August 23rd to 25th. As a result, the characteristics of vertical profile and daily variation of the pollutants are changed, and the concentrations of O3, NO2, SO2 in atmospheric boundary layer of Yufa area increased obviously.


Assuntos
Poluentes Atmosféricos/análise , Atmosfera/análise , Monitoramento Ambiental/métodos , Dióxido de Nitrogênio/análise , Movimentos do Ar , China , Ozônio/análise , Dióxido de Enxofre/análise
7.
Opt Express ; 15(8): 5227-36, 2007 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-19532774

RESUMO

An iterative algorithm is presented in this study for simultaneous determination of both the aerosol optical thickness and the exponent of the Junge power law from the total reflectance data of two satellite-based, near-infrared bands over the ocean. The atmospheric aerosol model is assumed as the Junge power-law size distribution in retrieval of the data. Numerical simulations show that relative errors in retrieval of the aerosol optical thickness and the exponent of the Junge power law are less than 5% when the actual atmospheric aerosol follows the Junge power-law size distribution. For other aerosol size distributions, relative errors of the aerosol optical thickness are less than approximately 10%. The proposed method is applied to a case study of the data of two near-infrared channels of the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) over the East China Sea area. The results show that reasonable spatial distribution of the exponent of the Junge law and the aerosol optical thickness may be obtained on a pixel-by-pixel basis through use of the proposed retrieval algorithm.

8.
Appl Opt ; 45(16): 3864-70, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16724151

RESUMO

A method is presented for inferring both the refractive index and the size distribution of aerosol from observations of a dual-scattering-angle optical particle counter (OPC). An existing prototype of an OPC with 60 degree and 90 degree dual-scattering angles was used for the experiments. Based on the high sensitivity of the OPC response to the refractive index of particulates, two families of size distribution curves may be calculated. The solution of the refractive index corresponds to the superposition of the two size distributions. This method was applied to the simulation and to the field measurements conducted in Beijing and Hefei, and the results of both are presented.

9.
Opt Lett ; 30(14): 1879-81, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16092376

RESUMO

A new method is presented to determine the geometrical form factor in Raman lidar. Mie and Raman backscattering signals are acquired by L625 Raman lidar; then the aerosol backscattering ratio and atmospheric molecular density are derived. By normalizing the molecular density of Raman lidar with radiosonde measurements, the geometrical form factors of lidar are obtained. Experimental results indicate this method is feasible.

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