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1.
Environ Monit Assess ; 195(12): 1542, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38012423

RESUMO

Natural mineral dust episodes elevate particle concentrations and eventually decrease air quality. Air pollutant emissions from aircraft, airport ground operations, and long-range dust transport are producing problems for the aviation sector. Dust transport from the Sahara Desert, one of the primary dust sources globally, significantly affects the eastern Mediterranean basin, including Türkiye. This study investigates the effect of long-range dust transport on particulate matter (PM) concentrations at Turkish airports. Three different approaches were used to analyse dust episodes in the study area. Firstly, routine reports of meteorological conditions at the airports were investigated. For this purpose, airport routine meteorological reports (Metar) and aviation-selected special weather report (Speci) codes, recorded at 11 airports from 2012 to 2021, were used to determine the dust episode days. Secondly, the hourly PM measurement dataset was analyzed from the closest air quality monitoring stations to the airports. Finally, regional atmospheric model results and backward-trajectory analysis were used to validate the dust episodes and determine the dust origin. Results showed that 163 dust episodes occurred during the study period, 17% from North Africa and 12% from the Mediterranean region.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aeroportos , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Material Particulado/análise , Poluição do Ar/análise , Poeira/análise
2.
Environ Monit Assess ; 195(9): 1021, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37548794

RESUMO

An integrated approach to understanding all measured pollutants with multi-discipline in different time scales and understanding the mechanisms hidden under low air quality (AQ) conditions is essential for tackling potential air pollution issues. In this study, the air pollution of Sivas province was analyzed with meteorological and PM2.5 data over six years to assess the city's AQ in terms of PM2.5 pollution and analyze the effect of meteorological factors on it. It was found that the winter period (January-February-November-December) of every year except 2019-which has missing data-is the period with the highest air pollution in the province. In addition, the days exceeding the daily PM2.5 limit values in 2016, 2017, 2020, and 2021 were also seen in the spring and summer months, which inclined the study to focus on additional pollutant sources such as long-range dust transport and road vehicles. The year 2017 has the highest values and was analyzed in detail. Pollution periods with the most increased episodes in 2018 were analyzed with the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) and Dust Regional Atmospheric Model (DREAM) models. As a result of the study, the average PM2.5 values in 2017 were 31.66 ± 19.2 µg/m3 and a correlation of -0.49 between temperature and PM2.5. As a result of model outputs, it was found that the inversion is intensely observed in the province, which is associated with an increase of PM2.5 during the episodes. Dust transport from northwestern Iraq and northeastern Syria is observed, especially on days with daily average PM2.5 values above 100 µg/m3. Additionally, planetary boundary layer (PBL) data analysis with PM pollution revealed a significant negative correlation (r = -0.61). Air pollutants, particularly PM2.5, were found to be higher during lower PBL levels.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Material Particulado/análise , Monitoramento Ambiental , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Poeira/análise , Estações do Ano , China
3.
Artigo em Inglês | MEDLINE | ID: mdl-30712532

RESUMO

BACKGROUND: Cryoballoon-based pulmonary vein isolation (PVI) is a treatment option for atrial fibrillation (AF). Left atrial volume (LAV) and left atrial volume index (LAVi) are important parameters for long term success of PVI. Galectin-3 (Gal-3) and neutrophil to lymphocyte ratio (N/L ratio) are biomarkers to demonstrate the cardiac fibrosis and remodelling. METHODS: 50 patients with symptomatic PAF despite ≥1 antiarrhythmic drug(s), who underwent PVI were enrolled. LAV, LAVi, Gal-3 and N/L ratio were calculated before ablation and after ablation at 6 and 12 months. According to AF recurrence patients were divided into two groups, recurrent AF (n = 14) and non-recurrent AF (n = 36). RESULTS: In both groups (recurrent and non-recurrent), initial and 12 months follow-up LAV values were 41.39 ±â€¯18.13 ml and 53.24 ±â€¯22.11 ml vs 48.85 ±â€¯12.89 ml and 42.08 ±â€¯13.85 (p = 0.037). LAVi were 20.9 ±â€¯8.91 ml/m2 and 26.85 ±â€¯11.28 ml/m2 vs 25.36 ±â€¯6.21 and 21.87 ±â€¯6.66 (p = 0.05) for recurrent and non-recurrent AF groups, respectively. In both groups PVI had no significant effect on serum Gal-3 levels and N/L ratio during 12 months follow-up. The comparison between two groups at the end of 12th month showed Gal-3 values of 6.66 ±â€¯4.09 ng/ml and 6.02 ±â€¯2.95 ng/ml (p = 0.516), N/L ratio values of 2.28 ±â€¯1.07 103/µl and 1.98 ±â€¯0.66 103/µl (p = 0.674). CONCLUSION: LAV and LAVi are useful to predict the remodelling of the left atrium and AF recurrence after cryoballoon-based PVI. However, biomarkers such as Gal-3 and N/L ratio are not associated with AF recurrence.

4.
Cardiol Young ; 25(3): 496-500, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24625682

RESUMO

OBJECTIVES: Insulin-like growth factor-1 may serve some regulatory function in the immune system. Rheumatic mitral stenosis is related to autoimmune heart valve damage after streptococcal infection. The aim of this study was to assess the level of insulin-like growth factor-1 and its correlation with the Wilkins score in patients with rheumatic mitral stenosis. METHODS: A total of 65 patients with rheumatic mitral stenosis and 62 age- and sex-matched control subjects were enrolled in this study. All subjects underwent transthoracic echocardiography. The mitral valve area and Wilkins score were evaluated for all patients. Biochemical parameters and serum insulin-like growth factor-1 levels were measured. RESULTS: Demographic data were similar in the rheumatic mitral stenosis and control groups. The mean mitral valve area was 1.6±0.4 cm2 in the rheumatic mitral stenosis group. The level of insulin-like growth factor-1 was significantly higher in the rheumatic mitral stenosis group than in the control group (104 (55.6-267) versus 79.1 (23.0-244.0) ng/ml; p=0.039). There was a significant moderate positive correlation between insulin-like growth factor-1 and thickening of leaflets score of Wilkins (r=0.541, p<0.001). CONCLUSIONS: The present study demonstrated that serum insulin-like growth factor-1 levels were significantly higher in the rheumatic mitral stenosis group compared with control subjects and that insulin-like growth factor-1 level was also correlated with the Wilkins score. It can be suggested that there may be a link between insulin-like growth factor-1 level and immune pathogenesis of rheumatic mitral stenosis.


Assuntos
Ecocardiografia , Fator de Crescimento Insulin-Like I/análise , Estenose da Valva Mitral/sangue , Estenose da Valva Mitral/patologia , Cardiopatia Reumática/sangue , Cardiopatia Reumática/patologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/diagnóstico por imagem , Cardiopatia Reumática/diagnóstico por imagem , Índice de Gravidade de Doença
5.
Int J Cardiovasc Imaging ; 24(3): 245-52, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17786582

RESUMO

OBJECTIVE: We aimed to study the comparison of strain and strain rate parameters with conventional left ventriculography derived regional function. METHOD: Forty patients were included in the study. The study group was selected from patients who had undergone left ventriculography and coronary angiography for clinical indications. Regional myocardial function was assessed using the centerline method via ACOM PC Quantcor LVA measurement system. Patients were also evaluated with echocardiography. Strain and strain rate Doppler echocardiographic measurements were compared with conventional left ventriculography at anterobasal, anterolateral, inferior and posterobasal segments. RESULTS: Radiological left ventricular radial shortening was found to correlate with longitudinal strain shortening in all ventriculographic segments examined (anterobasal, r = 0.771, P < 0.0001; anterolateral, r = 0.790, P < 0.0001; posterobasal, r = 0.861, P < 0.0001; inferior, r = 0.815, P < 0.0001). Correlation was persistent both in patients with or without coronary artery disease. The sensitivity of a peak systolic longitudinal strain >12.5% for prediction of patients with radial shortening >or=20% was 75%, with a specificity of 100%. However, no relationship could be demonstrated between radiological left ventricular radial shortening and strain rate measurements. CONCLUSIONS: In our study it was shown that regional wall motion can be measured quantitatively via strain Doppler echocardiography with the left ventriculography as reference.


Assuntos
Angiografia Coronária/métodos , Doença das Coronárias/diagnóstico por imagem , Ecocardiografia Doppler/métodos , Contração Miocárdica/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Doença das Coronárias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Disfunção Ventricular Esquerda/fisiopatologia
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