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1.
Bull Environ Contam Toxicol ; 110(3): 60, 2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36892662

RESUMEN

In this study we have analysed the elemental composition of fine particulate matter (PM2.5) to examine the seasonal changes and sources of the elements in Delhi, India from January, 2017 to December, 2021. During the entire sampling period, 19 elements (Al, Fe, Ti, Cu, Zn, Cr, Ni, As, Mo, Cl, P, S, K, Pb, Na, Mg, Ca, Mn, and Br) of PM2.5 were identified by Wavelength Dispersive X-ray Fluorescence Spectrometer. The higher annual mean concentrations of S (2.29 µg m-3), Cl (2.26 µg m-3), K (2.05 µg m-3), Ca (0.96 µg m-3) and Fe (0.93 µg m-3) were recorded during post-monsoon season followed by Zn > Pb > Al > Na > Cu > Ti > As > Cr > Mo > Br > Mg > Ni > Mn > and P. The annual mean concentrations of elemental composition of PM2.5 accounted for 10% of PM2.5 (pooled estimate of 5 year). Principal Component Analysis (PCA) identified the five main sources [crustal/soil/road dust, combustion (BB + FFC), vehicular emissions (VE), industrial emissions (IE) and mixed source (Ti, Cr and Mo rich-source)] of PM2.5 in Delhi, India.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Plomo/análisis , Monitoreo del Ambiente , India , Estaciones del Año , Iones/análisis
2.
Bull Environ Contam Toxicol ; 109(3): 502-510, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35322279

RESUMEN

Carbonaceous species [organic carbon (OC), elemental carbon (EC), elemental matter (EM), primary organic carbon (POC), secondary organic carbon (SOC), total carbon (TC), and total carbonaceous matter (TCM)] of PM2.5 were analyzed to study the seasonal variability and long-term trend of carbonaceous aerosols (CAs) in megacity Delhi, India from January, 2012 to April, 2021. The average concentrations (± standard deviation) of PM2.5, OC, EC, TC, EM, TCM, POC and SOC were 127 ± 77, 15.7 ± 11.6, 7.4 ± 5.1, 23.1 ± 16.5, 8.2 ± 5.6, 33.3 ± 23.9, 9.3 ± 6.3 and 6.5 ± 5.3 µg m-3, respectively during the sampling period (10-year average). The average CAs accounted for 26% of PM2.5 concentration during the entire sampling period. In addition, the seasonal variations in PM2.5, OC, EC, POC, SOC, and TCM levels were recorded with maxima in post-monsoon and minima in monsoon seasons. The linear relationship of OC and EC, OC/EC and EC/TC ratios suggested that the vehicular emissions (VE), fossil fuel combustion (FFC) and biomass burning (BB) are the major sources of CAs at megacity Delhi, India.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , China , Monitoreo del Ambiente , India , Tamaño de la Partícula , Material Particulado/análisis , Estaciones del Año
3.
J Environ Manage ; 298: 113484, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34391101

RESUMEN

Fabrication of novel metal oxide nanostructured composites is a proficient approach to develop efficient energy storage devices and development of cost-free and eco-friendly metal oxide nanostructures for supercapacitor applications received considerable attention in recent years. The Co3O4 nanocubes-NiO octahedral structured composite was constructed using facile and one-step calcination process. Cyclic voltammetry, charge-discharge, and electrochemical impedance spectral techniques have been employed to analyze the specific capacitance of the synthesized nanostructures and the composites. Specific capacitance and cycling stability of the composites were evaluated with the pristine Co3O4 and NiO nanostructures. The composite showed a specific capacitance of 832 F g-1 at a current density of 0.25 A g-1, which was ~1.5 and ~1.9-times higher than pristine Co3O4 nanocubes and NiO octahedral structure, respectively. On the other hand, electrode showed approximately 50 % capacity retention at a higher current density (5 Ag-1) because of the uniform morphology of Co3O4 and NiO. The charge-discharge stability measurements of the composite showed an admirable specific capacitance retention capability, which was 94.5 % after 2000 continuous charge-discharge cycles at a current density of 5 A g-1. The superior electrochemical performance of the nano-composite was ascribed to synergistic effects and uniform morphology. Efficient nanostructure development using facile and one-step calcination process and electrochemical performance make the synthesized composite a promising device for supercapacitor applications.


Asunto(s)
Nanocompuestos , Óxidos , Técnicas Electroquímicas , Electrodos
4.
Arch Environ Contam Toxicol ; 78(1): 79-85, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31832738

RESUMEN

Mixing ratios of atmospheric ammonia (NH3), nitric oxide (NO), carbon monoxide (CO), nonmethane hydrocarbons (NMHCs), and methane (CH4) were measured to investigate the vehicular emissions, which are a dominant source of atmospheric NH3 in urban sites of Delhi, India from January 2013 to December 2014. The annual average mixing ratios of NH3, NO, CO, NMHCs, and CH4 were 21.2 ± 2.1 ppb, 21.2 ± 6.1 ppb, 1.89 ± 0.18 ppm, 0.67 ± 0.21 ppm and 3.11 ± 0.53 ppm, respectively. Considering NO as a tracer of vehicular plume, ambient NH3 was correlated with NO during peak traffic hour in the morning (7:00-10:00 h) and evening (17:00-19:00 h) and observed significant positive correlation between them. Result reveals that the mixing ratio of atmospheric NH3 significantly positive correlated with traffic related pollutants (NO, CO, and NHHCs) during all the seasons (winter, summer, and monsoon). During winter, the average mixing ratio of atmospheric NH3 was increased by 1.2-3.5 ppb in the morning peak hour, whereas increased by 0.3-1.6 ppb in the evening peak hour. Similarly, an increase in NH3 mixing ratio was observed during summer (morning: 1.2-2.7 ppb and evening: 1.5-1.6 ppb) and monsoon (morning: 0.4-3.6 ppb and evening: 0.9-1.4 ppb) seasons. The results emphasized that the traffic could be one of the dominant source of ambient NH3 at the urban site of Delhi, as illustrated by positive relationships of NH3 with traffic related co-pollutants (NO, CO and NMHCs).


Asunto(s)
Contaminantes Atmosféricos/análisis , Amoníaco/análisis , Monóxido de Carbono/análisis , Monitoreo del Ambiente/métodos , Hidrocarburos/análisis , Óxidos de Nitrógeno/análisis , Emisiones de Vehículos/análisis , Ciudades , India , Óxido Nítrico/análisis , Dióxido de Nitrógeno/análisis , Estaciones del Año
6.
Bull Environ Contam Toxicol ; 100(5): 695-701, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29516139

RESUMEN

Organic carbon (OC) and elemental carbon (EC) in PM2.5 were estimated to study the seasonal and inter-annual variability of atmospheric total carbonaceous aerosols (TCA) at an urban site of megacity Delhi, India for 5 years from January, 2012 to December, 2016. The annual average (± standard deviation) concentrations of PM2.5, OC, EC and TCA were 128 ± 81, 16.6 ± 12.2, 8.4 ± 5.8 and 34.5 ± 25.2 µg m-3, respectively. During the study, significant seasonal variations in mass concentrations of PM2.5, OC, EC and TCA were observed with maxima in winter and minima in monsoon seasons. Significant correlations between OC and EC, and OC/EC ratio suggested that vehicular emissions, fossil fuel combustion and biomass burning could be major sources of carbonaceous aerosols of PM2.5 at the sampling site of Delhi, India.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Aerosoles/análisis , Biomasa , Carbono/análisis , China , India , Estaciones del Año , Emisiones de Vehículos/análisis
7.
Environ Monit Assess ; 189(1): 43, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28039660

RESUMEN

Delhi is one of the most polluted cities in the world. The generation of aerosols in the lower atmosphere of the city is mainly due to a large amount of natural dust advection and sizable anthropogenic activities. The compositions of organic compounds in aerosols are highly variable in this region and need to be investigated thoroughly. Twenty-four-hour sampling to assess concentrations of n-alkanes (ng/m3) in PM10 was carried out during January 2015 to June 2015 at Indira Gandhi Delhi Technical University for Women (IGDTUW) Campus, Delhi, India. The total average concentration of n-alkanes, 243.7 ± 5.5 ng/m3, along with the diagnostic tools has been calculated. The values of CPI1, CPI2, and CPI3 for the whole range of n-alkanes series, petrogenic n-alkanes, and biogenic n-alkanes were 1.00, 1.02, and 1.04, respectively, and C max were at C25 and C27. Diagnostic indices and curves indicated that the dominant inputs of n-alkanes are from petrogenic emissions, with lower contribution from biogenic emissions. Significant seasonal variations were observed in average concentrations of n-alkanes, which is comparatively higher in winter (187.4 ± 4.3 ng/m3) than during the summer season (56.3 ± 1.1 ng/m3).


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Estaciones del Año , Emisiones de Vehículos/análisis , Alcanos/análisis , Atmósfera , Ciudades , India , Compuestos Orgánicos/análisis
8.
Bull Environ Contam Toxicol ; 99(2): 281-285, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28321469

RESUMEN

In this study, ambient NH3, NO, NO2, CO and SO2 were measured continuously from February, 2008, to December, 2016. The annual average mixing ratios (mole/mole) of NH3, NO, NO2, CO and SO2 were 17.8 ± 3.4 ppb; 21.2 ± 2.3 ppb, 18.1 ± 3.2 ppb; 1.7 ± 0.3 ppm and 2.0 ± 0.3 ppb, respectively. All the trace gases (NH3, NO, NO2, CO and SO2) showed significant annual variation during the study. A significant increasing trend in mixing ratios of ambient NH3 and NO2 were observed at the observational site of Delhi, whereas, increasing trend were recorded in case of NO, CO and NO2 mixing ratios. The results emphasized that traffic could be one of the significant sources of ambient NH3 at the urban site of Delhi, as illustrated by positive correlations of NH3 with traffic related co-pollutants (NO and CO).


Asunto(s)
Contaminación del Aire/estadística & datos numéricos , Amoníaco/análisis , Monitoreo del Ambiente , Oligoelementos/análisis , Contaminantes Atmosféricos/análisis , Gases/análisis , Humanos , India
9.
Bull Environ Contam Toxicol ; 97(2): 286-93, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27209541

RESUMEN

Chemical characterization of PM2.5 [organic carbon, elemental carbon, water soluble inorganic ionic components, and major and trace elements] was carried out for a source apportionment study of PM2.5 at an urban site of Delhi, India from January, 2013, to December, 2014. The annual average mass concentration of PM2.5 was 122 ± 94.1 µg m(-3). Strong seasonal variation was observed in PM2.5 mass concentration and its chemical composition with maxima during winter and minima during monsoon. A receptor model, positive matrix factorization (PMF) was applied for source apportionment of PM2.5 mass concentration. The PMF model resolved the major sources of PM2.5 as secondary aerosols (21.3 %), followed by soil dust (20.5 %), vehicle emissions (19.7 %), biomass burning (14.3 %), fossil fuel combustion (13.7 %), industrial emissions (6.2 %) and sea salt (4.3 %).


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Modelos Químicos , Material Particulado/análisis , Aerosoles/análisis , Carbono/análisis , Polvo , India , Industrias , Estaciones del Año , Suelo , Emisiones de Vehículos/análisis
10.
Bull Environ Contam Toxicol ; 95(5): 661-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26438175

RESUMEN

This paper presents the variation of elemental concentrations of total carbon (TC), total nitrogen (TN) and isotopic ratios of δ13C and δ15N along with δ13OC and OC of PM10 mass over Delhi, Varanasi and Kolkata of the Indo Gangetic Plain (IGP), India. For Delhi, the average concentrations of TC and TN of PM10 were 53.0±33.6 and 14.9±10.8 µg m(-3), whereas δ13C and δ15N of PM10 were -25.5±0.5 and 9.6±2.8‰, respectively. For Varanasi, the average values of δ13C and δ15N of PM10 were -25.4±0.8 and 6.8±2.4‰, respectively. For Kolkata, TC and TN values for PM10 ranged from 9.1-98.2 to 1.4-25.9 µg m(-3), respectively with average values of 32.6±24.9 and 9.3±8.2 µg m(-3), respectively. The average concentrations of δ13C and δ15N were -26.0±0.4 and 7.4±2.7‰, respectively over Kolkata with ranges of -26.6 to -24.9‰ and 2.8±11.5‰, respectively. The isotopic analysis revealed that biomass burning, vehicular emission and secondary inorganic aerosols were likely sources of PM10 mass over IGP, India.


Asunto(s)
Contaminantes Atmosféricos/análisis , Isótopos de Carbono/análisis , Monitoreo del Ambiente/métodos , Isótopos de Nitrógeno/análisis , Material Particulado/análisis , Aerosoles/análisis , India , Tamaño de la Partícula , Urbanización , Emisiones de Vehículos/análisis
11.
Niger J Clin Pract ; 16(1): 100-3, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23377481

RESUMEN

BACKGROUND: Recent studies revealed elevated serum ferritin levels predict new-onset type 2 diabetes. Further studies proved ferritin to be an important and independent predictor of the development of diabetes. The link between hyperglycemia, enhanced free radical activity (oxidative stress) and serum iron and its stores (serum ferritin levels) levels is not clear. OBJECTIVES: The present study is an attempt to understand the relationship between serum ferritin levels and oxidative stress (measured by malondialdehyde). MATERIALS AND METHODS: The study comprised of 30 apparently healthy controls and 30 type 2 diabetic patients who attended the outpatient and inpatient departments of Medical College, Kolkata. Levels of fasting blood glucose, postprandial blood glucose, serum iron, serum ferritin, glycosylated hemoglobin (HbA1c) and malondialdehyde (MDA), serum urea and creatinine were estimated. The statistical software SPSS 11.0 and Systat 8.0 were used for the analysis of the data and Microsoft Word and Excel have been used to generate tables and graphs. RESULTS: Serum iron (82.16 ± 13.24 µg/dl), serum ferritin (224.53 ± 96.06 µg/L), HbA1c (8.62 ± 1.79%), MDA (2.66 ± 0.76 nmol/ml) levels were significantly higher in type 2 diabetics compared with apparently healthy controls. Elevations in serum iron, ferritin and HbA1c are accompanied by a parallel increase in blood glucose. Based on groups of glycemic control, i.e. HbA1c levels >8%, serum ferritin levels were highest, 258.63 ± 22.67 µg/dl. There is an inverse correlation of serum ferritin levels to MDA levels in the diabetic cases of longer duration of more than 10 years. CONCLUSION: Serum ferritin level in the present study is found to be higher in the newly diagnosed cases and lower in those patients suffering from diabetes for more than 10 years. This study probably suggests that serum ferritin can represent either as a pro-oxidant or as an antioxidant in a time-dependent manner.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Ferritinas/sangre , Hierro/sangre , Estrés Oxidativo , Adulto , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad
12.
Niger J Clin Pract ; 16(2): 216-20, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23563465

RESUMEN

BACKGROUND: Nephropathy is one of the complications of type 2 diabetes mellitus that could lead to end-stage renal disease. Persistent microalbuminuria is the best predictor of high risk of developing diabetic nephropathy. The relation between HbA 1c and microalbuminuria with the duration of diabetes is not clear. OBJECTIVES: To determine microalbuminuria levels in type 2 diabetics and to correlate changes in microalbuminuria levels to glycosylated hemoglobin level and duration of diabetes. MATERIALS AND METHODS: Study was conducted at Medical College, Kolkata. Fifty both male and female type 2 diabetics of age groups 30-60 years, without any complications were taken as cases and 50 healthy (male and female) subjects of comparable age were taken as controls. Cases with anemia, any other diseases or person using drugs that could affect HbA 1c levels and microalbuminuria were excluded from the study. Fasting and postprandial blood glucose, HbA 1c serum urea and serum creatinine were analyzed. Urine was analyzed for microalbuminuria. The Statistical Software SPSS 15.0 were used for the analysis of the data. RESULTS: Urinary microalbumin, HbA 1c levels were significantly higher in the cases. Microalbumin levels were linearly correlated to the duration of diabetes and HbA 1c. CONCLUSIONS: Impaired glycemic control is associated with significant elevations in urinary microalbumin levels. Furthermore, there is an increased urinary microalbumin levels with increased duration of diabetes, which suggests that the detection of increased urinary microalbumin levels at the initial stage can avert, reduce the clinical and economic burden of diabetic complications in future.


Asunto(s)
Albuminuria/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/orina , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/orina , Hemoglobina Glucada/metabolismo , Adulto , Albuminuria/orina , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
13.
Niger J Clin Pract ; 16(4): 424-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23974732

RESUMEN

BACKGROUND: Coronary Heart Disease (CHD) is the leading cause of death in many developed countries. The relation between heart rate variability (HRV) and CHD was recently explored after the development of HRV techniques. Lower HRV was proven to be associated with a greater risk for developing hypertension among normotensive men, and hypertension is one of the major risk factors of CHD. Acute myocardial infarction is accompanied by decreased HRV, which is due to reduced vagal or increased sympathetic outflow to the heart. AIM: This study was designed to test the hypothesis of influence of gender and lipid profile difference on heart rate variability tests. MATERIALS AND METHODS: Thirty healthy adult male and thirty healthy adult female subjects in the age group of 18- 25 years without any addictions and gross systemic disease were selected. Heart rate variability tests during Valsalva maneuver, deep breathing and 30:15 R-R intervals ratio were carried and lipid profile of the subjects were analyzed. RESULTS: We found a decrease in values of HRV tests during the Valsalva maneuver, deep breathing in male individuals as compared with age- and Body Mass Index, BMI-matched females. VHeart Rate Variability tests during 30:15 R-R intervals Ratio in male individuals were significantly decreased as compared with females. Values of total cholesterol, Low Density Lipoprotein, LDL cholesterol were found to be significantly increased and High Density Lipoprotein, HDL cholesterol significantly decreased in males. CONCLUSION: Healthy adult males may be at a higher risk of developing acute myocardial infarction and CHD due to decreased HRV and atherogenic lipid profile. Lower level of serum estrogen may be the cause of this difference in HRV among males. The difference in HRV tests among males and females disappears after menopause.


Asunto(s)
Enfermedad Coronaria/sangre , Enfermedad Coronaria/fisiopatología , Frecuencia Cardíaca/fisiología , Lípidos/sangre , Adulto , Antropometría , Electrocardiografía , Femenino , Humanos , Masculino , Valores de Referencia , Maniobra de Valsalva
14.
J Postgrad Med ; 58(4): 270-4, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23298922

RESUMEN

BACKGROUND: Feedback provided by integrating students' examination performance and the reflection on learning process may assist medical students to identify the essential learning processes required for better understanding of learning material. AIMS: To investigate the relationship between the student's learning process and examination performance and to explore students' perspectives on professional feedback given by integrating the self-reflection on learning process and individual examination performance. SETTINGS AND DESIGN: At the end of every medical school block examination, faculty provided descriptive feedback to students regarding individual performance in each subject area. The study had a quasi-experimental design. MATERIALS AND METHODS: Students' (n=153) self-reflection on learning process was collected using a reflection-in-learning scale. The learning process of the students categorized in fail, pass and first-class categories were compared. Students' self-reflection-in-learning and common mistakes found in answering essay questions were used to offer feedback. Students' perspectives regarding feedback were collected using a validated questionnaire. STATISTICAL ANALYSIS: Kruskal-Wallis test and Mann-Whitney test were used to analyze the data. A P<0.017 was considered as statistically significant. RESULTS: The median score of each item related to reflection was ≤ 4 (Scale 1-7) in all categories of students (n=153) reflecting a low level of reflection. There was a statistically significant difference in total reflection scores between fail (n=46) and first class category (n=42) students (P=0.002). The majority of students agreed feedback assisted in examination preparation, enhanced individual learning and allowed examinations to be viewed as more objective. CONCLUSIONS: This study shows the usefulness of the integration of medical students' reflection-in-learning practices and examination performance in providing descriptive feedback. This modified feedback process may have improved students' awareness leading to acceptance and a conscious practice of self-reflection and enhanced students' examination performance.


Asunto(s)
Educación de Pregrado en Medicina/métodos , Conocimiento Psicológico de los Resultados , Programas de Autoevaluación , Estudiantes de Medicina/psicología , Enseñanza/métodos , Adulto , Retroalimentación , Femenino , Humanos , Masculino , Autoevaluación (Psicología) , Encuestas y Cuestionarios
15.
Andrologia ; 44(2): 102-15, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21848871

RESUMEN

The present works examined an adverse effect of chlorpyrifos insecticide on testes and lipid peroxidation at low doses (5 mg-10 mg kg(-1) body weight) and the role of antioxidant enzymes systems at higher doses (20-30 mg kg(-1) body weight) in albino rats. At low doses, reduction in plasma levels of testosterone and FSH and LH hormones along with the significant shrinkage of seminiferous tubules and gametogenic changes in germ cells were noticed. But these changes were restored with the revival of serum testosterone, FSH and LH along with regression of testis at higher doses. Similarly, level of testicular lipid peroxidation was elevated, whereas levels of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) and steroidogenic enzymes activities (Δ(5) , 3ß-hydroxysteroid dehydrogenase and 17ß-hydroxysteroid dehydrogenase) were reduced significantly at low doses. But, rat testes showed a significant decrease in lipid peroxidation and concomitant increase in antioxidant enzymes and steroidogenic enzymes activities at higher doses. Results showed that at higher doses of chlorpyrifos treatments, rat testes were shown to trigger their natural defence mechanism which became operative possibly through corrective measure of synthesis of antioxidant defence enzymes and steroidogenic enzymes and pituitary gonadotrophins hormone feedback mechanisms.


Asunto(s)
Antioxidantes/metabolismo , Cloropirifos/toxicidad , Insecticidas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Testículo/efectos de los fármacos , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Animales , Peroxidación de Lípido/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Túbulos Seminíferos/efectos de los fármacos , Testículo/metabolismo , Testículo/patología , Testosterona/sangre
16.
Environ Monit Assess ; 184(10): 6187-96, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22083398

RESUMEN

Proper assessment of air quality status in an atmosphere based on limited observations is an essential task for meeting the goals of environmental management. A number of classification methods are available for estimating the changing status of air quality. However, a discrepancy frequently arises from the quality criteria of air employed and vagueness or fuzziness embedded in the decision making output values. Owing to inherent imprecision, difficulties always exist in some conventional methodologies like air quality index when describing integrated air quality conditions with respect to various pollutants parameters and time of exposure. In recent years, the fuzzy logic-based methods have demonstrated to be appropriated to address uncertainty and subjectivity in environmental issues. In the present study, a methodology based on fuzzy inference systems (FIS) to assess air quality is proposed. This paper presents a comparative study to assess status of air quality using fuzzy logic technique and that of conventional technique. The findings clearly indicate that the FIS may successfully harmonize inherent discrepancies and interpret complex conditions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Lógica Difusa
17.
Environ Monit Assess ; 162(1-4): 225-35, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19234750

RESUMEN

We present diurnal variation of ambient ammonia (NH(3)) in relation with other trace gases (O(3), CO, NO, NO(2), and SO(2)) and meteorological parameters at an urban site of Delhi during winter period. For the first time, ambient ammonia (NH(3)) was monitored very precisely and continuously using ammonia analyzer, which operates on chemiluminescence method. NH(3) estimation efficiency of the chemiluminescence method (>90%) is much higher than the conventional chemical trapping method (reproducibility 4.5%). Ambient NH(3) concentration reaches its maxima (46.17 ppb) at night and minimum during midday. Result reveals that the ambient ammonia (NH(3)) concentration is positively correlated with ambient NO (r(2) = 0.79) and NO(2) (r (2) = 0.91) mixing ratio and negatively correlated with ambient temperature (r(2) = - 0.32). Wind direction and wind speed indicates that the nearby (approximately 500 m NW) agricultural fields may be major source of ambient NH(3) at the observational site.


Asunto(s)
Amoníaco/análisis , Gases/química , Luminiscencia , Espectrofotometría Ultravioleta
18.
Environ Monit Assess ; 169(1-4): 1-13, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19757121

RESUMEN

The variation in air quality was assessed from the ambient concentrations of various air pollutants [total suspended particle (TSP), particulate matter < or =10 microm (PM(10)), SO(2), and NO(2)] for pre-Diwali, Diwali festival, post-Diwali, and foggy day (October, November, and December), Delhi (India), from 2002 to 2007. The extensive use of fireworks was found to be related to short-term variation in air quality. During the festival, TSP is almost of the same order as compared to the concentration at an industrial site in Delhi in all the years. However, the concentrations of PM(10), SO(2), and NO(2) increased two to six times during the Diwali period when compared to the data reported for an industrial site. Similar trend was observed when the concentrations of pollutants were compared with values obtained for a typical foggy day each year in December. The levels of these pollutants observed during Diwali were found to be higher due to adverse meteorological conditions, i.e., decrease in 24 h average mixing height, temperature, and wind speed. The trend analysis shows that TSP, PM(10), NO(2), and SO(2) concentration increased just before Diwali and reached to a maximum concentration on the day of the festival. The values gradually decreased after the festival. On Diwali day, 24-h values for TSP and PM(10) in all the years from 2002 to 2007 and for NO(2) in 2004 and 2007 were found to be higher than prescribed limits of National Ambient Air Quality Standards and exceptionally high (3.6 times) for PM(10) in 2007. These results indicate that fireworks during the Diwali festival affected the ambient air quality adversely due to emission and accumulation of TSP, PM(10), SO(2), and NO(2).


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Dióxido de Nitrógeno/análisis , Material Particulado/análisis , Dióxido de Azufre/análisis , Contaminación del Aire/estadística & datos numéricos , Atmósfera/química , Vacaciones y Feriados , Humanos , India , Exposición por Inhalación/análisis , Exposición por Inhalación/estadística & datos numéricos , Tiempo , Tiempo (Meteorología)
19.
J Environ Sci (China) ; 22(7): 1023-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21174992

RESUMEN

We present the diurnal and seasonal variability of ambient NH3, NO, NO2 and SO2 over Delhi, India. Ambient NH3, NO and NO2 were measured continuously during winter, summer and autumn seasons using NH3- and NOx-analyzer, which operates by chemiluminescence method with a higher estimation efficiency (> 90%) than the chemical trap method (reproducibility 4.7%). Prominent diurnal, day-to-day and seasonal variations of ambient mixing ratio of NH3, NO, NO2 and SO2 were observed during the study period. Seasonal variation with higher mixing ratio in winter was observed for all measured trace gases except NO. Day-night variation of all measured trace gases observed was higher in winter in comparison with summer. Late morning increase in NO2 mixing ratio might be attributed to conversion of NO to NO2 with the interaction of O3.


Asunto(s)
Amoníaco/análisis , Monitoreo del Ambiente , Óxido Nítrico/análisis , Dióxido de Nitrógeno/análisis , Estaciones del Año , Dióxido de Azufre/análisis , India , Luminiscencia
20.
J Diabetes Metab Disord ; 19(2): 1367-1379, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33520840

RESUMEN

PURPOSE: Hypertriglyceridemia (HG) is an independent risk factor with more prevalence than hypercholesterolemia and its attributes to cardiovascular disease (CVD) and pancreatitis. Hence, it becomes imperative to search for new triglyceride (TG) lowering agents. Tinospora cordifolia (TC) is a well-known Ayurvedic drug and a rich source of protoberberine alkaloids hence can contribute to TG lowering without side effects. Hence, to explore the therapeutic efficacy of T. cordifolia and its effects on biochemistry and metabolome in the patients of hyper-triglyceridemia, clinical trials were conducted. METHODS: Patients (n = 24) with hypertriglyceridemia were randomized into two groups to receive T. cordifolia extract (TCE) (3.0 g/per day) and metformin (850 mg/day) for 14 days having >300 mg/dl triglyceride level and cholesterol in the range of 130-230 mg/dl. Lipid profiles of blood samples were analyzed. Urine samples were subjected to HPLC-QTOF-MS to quantify oxidative damage and abnormal metabolic regulation. RESULTS: Intervention with TCE reduced the triglyceride, LDL, and VLDL levels to 380.45 ± 17.44, 133.25 ± 3.18, and 31.85 ± 5.88 mg/dL and increased the HDL to 47.50 ± 9.05 mg/dL significantly (p < 0.05) in the HG patients after 14 days treatment. TCE dosage potently suppressed the inflammatory and oxidative stress marker's i.e. levels of isoprostanes significantly (p < 0.01). Qualitative metabolomics approach i.e. PCA and PLS-DA showed significant alterations (p < 0.05) in the levels of 40 metabolites in the urine samples from different groups. CONCLUSION: TCE administration depleted the levels of markers of HG i.e. VLDL, TG, and LDL significantly. Metabolomics studies established that the anti-HG activity of TCE was due to its antioxidative potential and modulation of the biopterin, butanoate, amino acid, and vitamin metabolism. CLINICAL TRIALS REGISTRY: India (CTRI) registration no. CTRI- 2016-08-007187.

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