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1.
J Environ Radioact ; 262: 107146, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36898251

RESUMEN

A systematic mapping of natural absorbed dose rate was carried out to assess the existing exposure situation in India. The mammoth nationwide survey covered the entire terrestrial region of the country comprising of 45127 sampling grids (grid size 36 km2) with more than 100,000 data points. The data was processed using Geographic Information System. This study is based on established national and international approaches to provide linkage with conventional geochemical mapping of soil. Majority (93%) of the absorbed dose rate data was collected using handheld radiation survey meters and remaining were measured using environmental Thermo Luminescent Dosimeters. The mean absorbed dose rate of the entire country including several mineralized regions, was found to be 96 ± 21 nGy/h. The median, Geometric Mean and Geometric Standard Deviation values of absorbed dose rate were 94, 94 and 1.2 nGy/h, respectively. Among the High Background Radiation Areas of the country, absorbed dose rate varied from 700 to 9562 nGy/h in Karunagappally area of Kollam district, Kerala. The absorbed dose rate in the present nationwide study is comparable with the global database.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Contaminantes Radiactivos del Suelo/análisis , Suelo , India , Dosímetros de Radiación , Radiación de Fondo , Dosis de Radiación
2.
J Mol Graph Model ; 119: 108399, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36563644

RESUMEN

In this work, we studied the hydrogen adsorption capabilities of functionalized graphene sheets containing a variety of defects (D-G) via molecular dynamics (MD) simulations that govern the mechanisms involved in hydrogen adsorption. Specifically, the graphene sheets containing monovacancy (MV), Stone-Wales (SW), and multiple double vacancy (DV) defects were functionalized with Ti and N atoms to enhance their hydrogen adsorption capacity. We measured the adsorption capacities of the N-/D-G sheets with varying concentrations of Ti adatoms at 300 K and 77 K temperatures and various pressures. Our study revealed that the increasing concentration of Ti adatoms on the D-G sheets led to a significant improvement in the hydrogen adsorption capacity of the graphene sheets. The DV(III)-G sheets showed the maximum adsorption capacity at 300 K because the DV(III)-G sheets had a small number of large-sized pores that bind hydrogen with high binding energy. Thus, hydrogen remained adsorbed even at higher temperatures (300 K). The N doping on the D-G sheets initially reduced their hydrogen adsorption capabilities; however, the N-D-G sheets enhanced their hydrogen adsorption capacity with the increasing concentrations of Ti adatoms. Compared to all other defect types, the Ti-N-DV(III)-G sheet with a Ti concentration of 10.5% showed a hydrogen uptake of 5.5 wt% at 300 K and 100 bar pressure. Thus, the N doping and Ti implantations improved the hydrogen storage capabilities of the graphene sheets, and these findings helped design solid-state hydrogen storage systems operating at ambient conditions and moderate pressure ranges.


Asunto(s)
Grafito , Grafito/química , Adsorción , Hidrógeno/química , Titanio/química , Simulación de Dinámica Molecular
3.
Chemosphere ; 298: 134271, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35276107

RESUMEN

The world's worst outbreak, the second COVID-19 wave, not only unleashed unprecedented devastation of human life, but also made an impact of lockdown in the Indian capital, New Delhi, in particulate matter (PM: PM2.5 and PM10) virtually ineffective during April to May 2021. The air quality remained not only unabated but also was marred by some unusual extreme pollution events. SAFAR-framework model simulations with different sensitivity experiments were conducted using the newly developed lockdown emission inventory to understand various processes responsible for these anomalies in PM. Model results well captured the magnitude and variations of the observed PM before and after the lockdown but significantly underestimated their levels in the initial period of lockdown followed by the first high pollution event when the mortality counts were at their peak (∼400 deaths/day). It is believed that an unaccounted emission source was playing a leading role after balancing off the impact of curtailed lockdown emissions. The model suggests that the unprecedented surge in PM10 (690 µg/m3) on May 23, 2021, though Delhi was still under lockdown, was associated with large-scale dust transport originating from the north west part of India combined with the thunderstorm. The rainfall and local dust lifting played decisive roles in other unusual events. Obtained results and the proposed interpretation are likely to enhance our understanding and envisaged to help policymakers to frame suitable strategies in such kinds of emergencies in the future.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , COVID-19/epidemiología , Ciudades , Control de Enfermedades Transmisibles , Polvo , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , SARS-CoV-2
4.
Int J Environ Sci Technol (Tehran) ; 19(6): 5649-5658, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34226828

RESUMEN

This study estimates the potential source regions contributing to PM2.5 in the capital city of Thimphu, Bhutan, during the years 2018-2020 using the ground-based data, followed by the HYSPLIT back trajectory analysis. The average PM2.5 concentration in the entire study period was 32.47 µg/m3 which is three times of the World Health Organization recommended limit of 10 µg/m3. Less than half of the days in pre-monsoon (43.47%) and post-monsoon (46.41%), and no days in winter were within the 24-h average WHO guideline of 25 µg/m3. During the COVID-19 lockdown imposed from August 11 to September 21 in Bhutan, only a marginal reduction of 4% in the PM2.5 concentrations was observed, indicating that nonlocal emissions dominate the PM2.5 concentrations in Thimphu, Bhutan. Most back trajectories in the analysis period were allocated to south or south-west sector. India was the major contributor (~ 44%), followed by Bangladesh (~ 19%), Bhutan itself (~ 19%) and China (~ 16%). This study confirms that there are significant contributions from transboundary sources to PM2.5 concentrations in Thimphu, Bhutan, and the elevated PM2.5 concentrations need to be tackled with appropriate action plans and interventions.

5.
J Environ Manage ; 296: 113227, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34261034

RESUMEN

The adverse effect of barge movement on the river's aquatic ecosystem is of global concern. The phytoplankton community, a bioindicator, is possibly the foremost victim of the barge movement. This study hypothesized phytoplankton diversity loss induced by barge movement in a large river. This article presents a novel risk assessment framework to evaluate the hypothesis-with a goal to uncoupling phytoplankton diversity loss due to barge movement over a spatiotemporal scale. For this purpose, a study was conducted in the Bhagirathi-Hooghly stretch of Inland National Waterway 1 of India. This study has proposed a new index of diversity loss and its inferential framework based on full Bayesian Generalized Linear Mixed Model. The results have diagnosed significant barge-induced impact on the phytoplankton diversity and identified ten most impacted species. The proposed framework has successfully disentangled barge-induced phytoplankton diversity loss from the biological process and predicted a substantive overall risk of phytoplankton loss of 31.44%. Besides, it has uncoupled spatiotemporal differential estimates, suggesting a risk of diversity loss in order of 'During vs After' (38.0%) > 'Before vs After' (30.7%) > 'Before vs During' (24%) barge movement in temporal scale and increasing diversity loss along downstream. Finally, the instant study has highlighted the utility of these results to facilitate better water framework directive for inland waterways.


Asunto(s)
Ecosistema , Fitoplancton , Teorema de Bayes , Biodiversidad , Ríos
6.
Heliyon ; 7(2): e06142, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33553707

RESUMEN

Air pollution is linked to higher rates of human mortality especially those infected with COVID 19. Ozone is a harmful pollutant and is responsible for many health issues. However, some reports suggest that ozone is a strong disinfectant, and can kill the viruses. We hereby, report on the vulnerability of ozone due to COVID-19 lockdown whose levels flutter from surging to saturation in a highly polluted Indian capital, due to significant decline in anthropogenic emissions of ozone precursors. Average observed levels stabilized at 30 ppb, 12 ppb, 740 ppb, and 900 ppb for ozone (O3), nitrogen dioxide (NO2), carbon monoxide (CO) and volatile organic compounds (VOCs) respectively during lockdown period from 27th March to 10th April 2020. The NO2, CO and VOC declined by 50 %, 37 %, 38 % respectively during the lockdown period of 2020 as compared to similar period in 2019. The anomalous response of ozone during the lockdown is explained by resolving the poorly known complex O3-NOx-VOCs mechanism with the help of data from air monitoring stations in Delhi, India. The data obtained from this study advances the fundamental understanding of ozone chemistry that may lead to improved ozone parameterization in chemical transport models and better planning of ozone risk management strategies for any global mega cities.

7.
Environ Res ; 191: 110121, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32835684

RESUMEN

The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is rapidly spreading across the globe due to its contagion nature. We hereby report the baseline permanent levels of two most toxic air pollutants in top ranked mega cities of India. This could be made possible for the first time due to the unprecedented COVID-19 lockdown emission scenario. The study also unfolds the association of COVID-19 with different environmental and weather markers. Although there are numerous confounding factors for the pandemic, we find a strong association of COVID-19 mortality with baseline PM2.5 levels (80% correlation) to which the population is chronically exposed and may be considered as one of the critical factors. The COVID-19 morbidity is found to be moderately anti-correlated with maximum temperature during the pandemic period (-56%). Findings although preliminary but provide a first line of information for epidemiologists and may be useful for the development of effective health risk management policies.


Asunto(s)
Contaminación del Aire , Infecciones por Coronavirus , Pandemias , Neumonía Viral , Contaminación del Aire/análisis , Betacoronavirus , COVID-19 , Ciudades , Humanos , India , SARS-CoV-2 , Tiempo (Meteorología)
9.
Mar Pollut Bull ; 140: 262-273, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30803642

RESUMEN

The occurrence of microplastic particles were evaluated on beaches along the Indian coast from three different locations Girgaon Mumbai (Arabian sea coast), Tuticorin, and Dhanushkodi (Bay of Bengal coast). Density separation method was adopted for isolation of microplastics from sand. Isolated microplastics were characterized using three different analytical techniques e.g. fluorescence microscopy (after staining with Nile Red), FTIR and SEM-EDS techniques. Microplastic concentrations in beach sands were from 45 ±â€¯12 # MP kg-1 to 220 ±â€¯50 # MP kg-1 of dry sand. The order of abundance of plastic type was polyethylene (43%) > polyethylene terephthalate (17.3%) ≈ polystyrene (17%) > polypropylene (12.3%) > Others (11%) > polyvinylchloride (1.33%), and very similar profile was observed for all monitored locations. SEM images show microplastics surfaces with characteristic cracks, suggests their polymer aging, mechanical and oxidative weathering, which was found highest for the microplastics collected from Mumbai.


Asunto(s)
Playas , Monitoreo del Ambiente/métodos , Plásticos/análisis , Cuarzo , Contaminantes Químicos del Agua/análisis , India , Océanos y Mares , Plásticos/química , Contaminantes Químicos del Agua/química
10.
Arch Environ Contam Toxicol ; 76(1): 142-152, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30361943

RESUMEN

The fate of a pollutant in the environment depends on its interaction with the surroundings. Henry's law constant (HLC) is one of the important properties useful for assessment of environmental risk and estimation of mass transfer of the pollutant between water and air. Estimation of HLC is relatively a difficult task for many of the organic pollutants due to their very low aqueous solubility. People have attempted the measurement of HLC for persistent organic pollutants, such as polychlorinated biphenyls (PCBs), but due to the difficulty in estimation, there is a variation of approximately 2-3 orders of magnitude in reported values of HLC for PCBs in the literature. A study was performed for estimation of HLC for PCBs using the static method with a modification that eliminates any disturbance in equilibrium due to sampling and also avoids removal or addition of material in or out of the system unlike the conventional methods. The results were consistent with the literature values. The experimental values of HLC ranged from 0.004 to 0.08 for different congeners. All of the experimental values were in agreement with the literature values. The experimental data was further used for deriving a correlation equation for theoretical estimation of the HLC from aqueous solubility and chlorination number. The equation gave a very good estimation of HLC values for all the PCBs congeners except single- and double-chlorinated congeners. The theoretically predicted values were also found to be in close agreement with the reported HLC values.


Asunto(s)
Aire , Contaminantes Ambientales/análisis , Modelos Teóricos , Bifenilos Policlorados/análisis , Agua/química , Monitoreo del Ambiente , Contaminantes Ambientales/química , Halogenación , Bifenilos Policlorados/química , Solubilidad , Volatilización
11.
Iran J Vet Res ; 19(3): 217-224, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30349569

RESUMEN

This study compared the therapeutic efficacy of levofloxacin, ornidazole and alpha tocopherol combination and prostaglandin F2α (PGF2α) in longstanding cases of endometritis and evaluated their impact on Interleukin-6 (IL-6) and Interleukin-10 (IL-10) transcript level in peripheral blood leukocytes. Eighteen endometritic crossbred Jersey cows were randomly allotted to three groups (six in each) viz. Group I (levofloxacin combo treatment I/U), group II (PGF2α treatment I/M), group III (no treatment, control), and group IV (six non-endometritic healthy cyclic) was taken for comparison study. The clinical efficacy was assessed by haematological study (TLC: Total leukocyte count; DC: Differential count), polymorphonuclear leukocytes (PMN) count in uterine cytology and relative mRNA expression of IL-6 and IL-10 in peripheral blood leukocytes before and after treatment with respect to conception rate following single and second inseminations. Group I and II registered significant increase in TLC and neutrophil count. PMN cytology was increased two and three fold in group I and II, respectively. The IL-6 transcript level was increased by 2.5 and 4.6 fold while that of IL-10 increased by 3.7 and 5.2 fold in group I and II, respectively. Conception rate across group I to IV following single insemination was found to be 66.67%, 50%, 16.67%, and 83.33% and their corresponding values following second insemination were 66.67%, 83.33%, 16.67%, and 83.33%, respectively. Thus, the administration of levofloxacin combo and PGF2α might have better conception rate following first and second insemination, respectively. Our study also reveals that PGF2α could register better clearance of bacteria through stronger PMN cell and cytokine activity in post-treatment period.

12.
Mar Pollut Bull ; 131(Pt A): 453-459, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29886971

RESUMEN

The sedimentation rates in Arctic fjords are influenced by the changes in the glacial inputs. The recent studies have indicated the retreat of glaciers due to climate change and subsequent increase in melt water outflow with high content of debris. The debris may contain natural and anthropogenically originated contaminants. The present study analysed the sedimentation rate in inner Kongsfjorden, Ny-Ålesund, Svalbard using 210Pb/210Po dating technique. The sedimentation rate ranged between 0.22 and 0.37 cm/year during the last 112 years. The average sedimentation rate obtained was 0.28 cm/y. The rate has been increased during the last 20 years and it might be due to the increased influx of glacial melt water containing debris. Metals and other elements showed an increasing trend towards the surface and observed high deposition rate since 1970s, indicating influence of industrial emissions and it can be a potential threat to Arctic biota.


Asunto(s)
Sedimentos Geológicos/análisis , Metales/análisis , Contaminantes Químicos del Agua/análisis , Regiones Árticas , Monitoreo del Ambiente/métodos , Estuarios , Sedimentos Geológicos/química , Cubierta de Hielo , Radioisótopos de Plomo/análisis , Polonio/análisis , Svalbard
13.
Appl Radiat Isot ; 135: 57-60, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29396212

RESUMEN

A method was optimized for detecting trace elements in sea water using Energy dispersive X-ray fluorescence (EDXRF) technique. Sea water samples were pre-concentrated using ammonium pyrrolidinedithiocarbamate (APDC) as chelating agent and methyl isobutyl ketone (MIBK) as organic phase. The preconcentrated samples were dried to form thin films on mylar substrate and analysed using EDXRF spectrometer. The multi-element standard samples prepared in synthetic sea water were used for EDXRF instrument calibration. The instrument was calibrated for 11 elements namely As, Cd, Co, Cr, Fe, Ga, Pb, Se, Sc, V and Zn using linear regression method for concentration up to 200 ppb. The detection limits achieved for As, Cd, Co, Cr, Fe, Ga, Pb, Se, Sc, V and Zn were 13, 70, 5.1, 36, 15, 36, 23, 11, 20, 13 and 40 ppb respectively. The optimized method was used for determination of elements in sea water collected from the Thane creek, Mumbai, India. The results were checked for accuracy by comparing it with inductively coupled plasma atomic emission spectroscopy (ICP AES) technique. The comparison showed the discrepancy of results to be insignificant at 95% confidence level.

14.
Public Health Action ; 7(1): 15-20, 2017 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-28775938

RESUMEN

Setting: The public-private mix (PPM) tuberculosis (TB) project implemented by the Myanmar Medical Association (MMA) in 105 townships in Myanmar. Objectives: 1) To assess the contribution of the MMA-PPM-TB project to total TB patient notification in the project townships; 2) to evaluate the outcomes of patients treated at the MMA-PPM clinics; and 3) to identify factors associated with unfavourable treatment outcomes, from January to December 2013. Design: A retrospective cohort study. Results: The MMA-PPM-TB project contributed 7501 (12%) of 60 905 TB patient notifications to the National Tuberculosis Programme (NTP) in 105 study townships. Of 2975 TB patients diagnosed and treated at private MMA-PPM clinics, 92% had a favourable outcome (32% cured, 60% completed treatment) and 8% had an unfavourable outcome (2.9% died, 2.5% lost to follow-up, 1.9% failure, 0.6% transfer out). Patient characteristics significantly associated with an unfavourable treatment outcome were age ⩾65 years (adjusted risk ratio [aRR] 5.7, 95% confidence interval [CI] 4.20-7.68), retreatment (aRR 2.44, 95%CI 1.79-3.33) and female sex (aRR 1.44, 95%CI 1.14-1.82). Conclusion: This study supports the continuation and expansion of the MMA-PPM-TB model and/or similar PPM approaches in Myanmar that engage all health providers in the ambitious goals of achieving universal health coverage in this country in transition and ending its TB epidemic by 2035.


Contexte : Le projet mixe public-privé (PPM) pour la tuberculose (TB) mis en œuvre par l'association médicale du Myanmar (MMA) dans 105 townships, Myanmar.Objectifs : 1) Evaluer la contribution du projet TB MMA-PPM à la notification totale des patients TB dans les townships du projet ; 2) évaluer le devenir des patients traités dans les centres de santé MMA-PPM ; et 3) identifier les facteurs associés avec un résultat défavorable du traitement de janvier à décembre 2013.Schéma : Étude rétrospective de cohorte.Résultats : Le projet MMA-PPM-TB a contribué à 7501 (12%) des 60 905 notifications de patients TB au Programme National TB dans les 105 townships de l'étude. Parmi 2975 patients TB diagnostiqués et traités dans les centres privés du MMA-PPM, 92% ont eu un résultat favorable (32% de guérison, 60% d'achèvement) et 8% des patients ont eu un résultat défavorable (2,9% sont décédés, 2,5% ont été perdus de vue, 1,9% ont eu un échec du traitement et 0,6% ont déménagé). Les caractéristiques des patients significativement associées avec un résultat défavorable du traitement ont été l'âge ⩾65 ans (ratio de risque ajusté [aRR] 5,7 ; intervalle de confiance [IC] 95% 4,20­7,68), le retraitement (aRR 2,44 ; IC95% 1,79­3,33) et le sexe féminin (aRR 1,44 ; IC95% 1,14­1,82).Conclusion : Cette étude est en faveur de la poursuite et de l'expansion du modèle MMA-PPM-TB et/ou d'approches similaires public-privé au Myanmar, engageant tous les prestataires de santé, car ce pays en transition présente une vision audacieuse consistant à offrir une couverture santé universelle et à mettre fin à l'épidémie de TB d'ici 2035.


Marco de referencia: El proyecto de colaboración público-privada (PPM) en materia de tuberculosis (TB) puesta en práctica por la Asociación Médica de Myanmar (MMA) en 105 municipios de Birmania.Objetivos: 1) Evaluar la contribución del MMA-PPM-TB en Birmania al total de notificaciones de casos de TB en los municipios que participaron; 2) evaluar los desenlaces clínicos de los pacientes tratados en los consultorios participantes; y 3) definir los factores que se asociaron con los desenlaces terapéuticos desfavorables, de enero a diciembre del 2013.Método: Fue este un estudio retrospectivo de cohortes.Resultados: El MMA-PPM-TB aportó 7501 casos (12%) a las 60 905 notificaciones de pacientes al Programa Nacional contra la TB en los 105 municipios que participaron en el estudio. De los 2975 pacientes diagnosticados con TB y tratados en los consultorios del MMA-PPM-TB, el 92% logró un desenlace terapéutico favorable (32% curaciones y 60% tratamientos completos) y el 8% obtuvo un desenlace desfavorable (2,9% defunciones, 2,5% pérdidas durante el seguimiento, 1,9% fracasos y 0,6% transferencias a otros centros). Las características que se asociaron de manera significativa con un desenlace desfavorable fueron la edad ⩾65 años (riesgo relativo ajustado [RRa] 5,7; intervalo de confianza [IC] del 95% 4,20­7,68), los pacientes en retratamiento (RRa 2,44; IC95% 1,79­3,33) y el sexo femenino (RRa 1,44; IC95% 1,14­1,82).Conclusión: Los resultados del presente estudio respaldan la continuación y la ampliación del modelo de MMA-PPM-TB y de otras iniciativas equivalentes de PPM en Birmania que vinculen a todos los profesionales de salud, pues el país en un momento de transición pone en marcha una perspectiva ambiciosa de cobertura universal de salud y de erradicación de la epidemia de TB en el 2035.

15.
Aust Vet J ; 95(8): 281-288, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28749022

RESUMEN

OBJECTIVE: The aim of this research was to study the roles of the day 0 energy balance and gonadotrophin-releasing hormone (GnRH) and progesterone levels on dominant follicle (DF) and corpus luteum (CL) development during the first 7 days of a gonadotrophin-prostaglandin-gonadotrophin (GPG) + progesterone (P4) program in anoestrous dairy cows. METHODS: Cows (n = 81) were allocated to one of the three treatments: (1) GPG + P4 (days 0 and 9, 100 µg GnRH; day 0-7, intravaginal P4 device; day 7, 500 µg PGF2α ); (2) GPG (as for treatment 1 but excluding the P4 device) and (3) prostaglandin + GnRH + P4 (as for treatment 1, but excluding day 0 GnRH). DF and CL size, plasma concentrations of insulin, insulin-like growth factor-I (IGF-I) and non-esterified fatty acid (NEFA) were measured on days 0 and 7. RESULTS: The proportion of cows with a CL on day 7 was significantly different between groups (GPG: 78%, GPG+P4: 69%, PGF2α + GnRH + P4: 42%, P = 0.02). The CL volume on day 7 was significantly associated with treatment, treatment by time postpartum and plasma concentrations of insulin, IGF-I and NEFA. CONCLUSION: In cows without a CL present on day 0 of an oestrus synchronisation program, removal of the day 0 GnRH treatment led to reduced CL development; however, no effect of adding progesterone was found. In contrast, in cows with a CL present on day 0 inclusion of a progesterone device led to a higher CL volume, but removal of the first GnRH injection had no effect. Response to the treatment was affected by plasma concentrations of insulin, IGF-I and NEFA.


Asunto(s)
Bovinos/fisiología , Dinoprost/farmacología , Sincronización del Estro , Hormona Liberadora de Gonadotropina/farmacología , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/fisiología , Anestro/efectos de los fármacos , Animales , Femenino , Inseminación Artificial , Ovulación/efectos de los fármacos , Progesterona/administración & dosificación , Progesterona/farmacología , Distribución Aleatoria
16.
Sci Total Environ ; 584-585: 1130-1137, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-28153404

RESUMEN

Data are analyzed in terms of daily average ozone, its diurnal variation and its relation with meteorological parameters like dry bulb temperature (T), wet bulb temperature (Tw), atmospheric pressure and wind speed based on measurement of these parameters at two Indian Antarctic stations (Larsemann Hills, and Maitri) during 28th Indian Scientific Expedition of Antarctica (ISEA) organized during Antarctic summer of the year 2008-09. The work has been carried out to investigate summer time ozone level and its day-to-day and diurnal variability at these coastal locations and to highlight possible mechanism of ozone production and destruction. The result of the analysis indicates that daily average ozone concentration at Larsemann Hills varied from ~13 and ~20ppb with overall average value of ~16ppb and at Maitri, it varied from ~16 and ~21ppb with overall average value of ~18ppb. Photochemistry is found to partially contribute occasionally to the surface layer ozone at both the stations. Lower concentration of ozone at Maitri during beginning of the observational days may be due to destruction of ozone through activated halogens, whereas higher ozone on latter days may be due to photochemistry and advective transport from east to south-east areas. Ozone concentration during blizzard episodes at both the stations is reduced due to slow photochemical production of ozone, its photochemical removal and removal through deposition of ozone molecules on precipitation particles. Diurnal variation of ozone at Larsemann Hills and Maitri has been found to be absent.

17.
Bull Environ Contam Toxicol ; 98(4): 534-538, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28084508

RESUMEN

Trace metals (Pb, Cu and Cd) in seawater samples were pre-concentrated for the simultaneous quantitative determination using solvent extraction procedure in the presence of ammonium pyrrolidine dithiocarbamate (APDC) as complexing agent and methyl isobutyl ketone (MIBK) as organic phase and acid exchange back - extraction followed by its determination by Differential Pulse Anodic Stripping Voltammetry (DPASV). Concentrations of Pb, Cu and Cd vary from 3.0 to 9.44 ng/mL, 12.7 to 28.6 ng/mL and 0.31 to 1.21 ng/mL respectively in seawater samples collected from different locations across Thane Creek area, Mumbai, India. Pb, Cu, Cd concentration were observed to be higher in the eastern side of the Thane Creek as it is covered by various industries.


Asunto(s)
Cadmio/análisis , Cobre/análisis , Plomo/análisis , Agua de Mar/química , Técnicas de Química Analítica/métodos , India , Oligoelementos/análisis
18.
Environ Toxicol Pharmacol ; 50: 58-66, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28131077

RESUMEN

We report levels of polycyclic aromatic hydrocarbons in sediment, seawater, fish and crab samples from Thane creek, India. Concentrations of sixteen USEPA PAH in sediments varies from 874 to 1925ngg-1, dry weight (dw) in winter, between 219-495ngg-1 in summer. In seawater Σ16 PAHs concentration during winter was recorded 706±193ngL-1, and during summer 337±79ngL-1. Total concentrations of PAHs in consumable portion of lizard fish, bombay duck and crab were found 156.8±18 and 122±24.5ngg-1, 117.4±17.65ngg-1 and 95.8±16.2ngg-1, 348±94.5 and 95.62±31.9ngg-1 wet weight (ww) in summer and winter respectively. PAHs concentration were compared with sediments quality guidelines viz. ERL-ERM, TEL-PEL indexes for finding ecotoxicological risk on marine organism. The ILCR values were above public screening criteria for carcinogens.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminación Ambiental/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Organismos Acuáticos/química , Peces , Sedimentos Geológicos/análisis , Humanos , India , Medición de Riesgo , Estaciones del Año , Agua de Mar/análisis , Mariscos/análisis
19.
Int J Inj Contr Saf Promot ; 24(1): 32-43, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26167639

RESUMEN

Being a powerful tool in modelling industrial and service operations, Petri net (PN) has been extremely used in different domains, but its application in safety study is limited. In this study, we model the gantry crane operations used for industrial activities using generalized stochastic PNs. The complete cycle of operations of the gantry crane is split into three parts namely inspection and loading, movement of load, and unloading of load. PN models are developed for all three parts and the whole system as well. The developed PN models have captured the safety issues through reachability tree. The hazardous states are identified and how they ultimately lead to some unwanted accidents is demonstrated. The possibility of falling of load and failure of hook, sling, attachment and hoist rope are identified. Possible suggestions based on the study are presented for redesign of the system. For example, mechanical stoppage of operations in case of loosely connected load, and warning system for use of wrong buttons is tested using modified models.


Asunto(s)
Industria de la Construcción , Salud Laboral , Industria de la Construcción/métodos , Humanos , Modelos Teóricos
20.
Public Health Action ; 6(3): 169-175, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27695679

RESUMEN

Setting: The three government tertiary care hospitals providing care for people living with the human immunodeficiency virus (PLHIV) in Kathmandu, Nepal. Objectives: To assess 1) the screening cascades for intensified case finding for tuberculosis (TB), 2) isoniazid preventive therapy (IPT), including demographic and clinical factors associated with treatment interruption, and 3) TB infection control (IC) in the health facilities. Design: A cross-sectional study of new PLHIV enrolled from January 2012 to December 2014. Results: Among 572 registered PLHIV, 91% were on antiretroviral therapy. Of those registered, 561 (98%) were screened for TB and 73 (13%) were diagnosed with TB (17 [25%] sputum smear-positive, 17 [25%] smear-negative and 35 [51%] extra-pulmonary). Among the 488 (87%) PLHIV without active TB, 157 (32%) were initiated on IPT, of whom 136 (87%) completed treatment and 17 (11%) interrupted treatment. Those who experienced adverse events were 12 times more likely to interrupt IPT. TB IC showed gaps in personal control measures and supporting structures and policies. Conclusion: The implementation of the Three I's for collaborative TB-HIV activities in pilot sites in Nepal was successful and should be scaled up.


Contexte : Les trois hôpitaux d'état de niveau tertiaire offrant des soins aux personnes vivant avec le virus de l'immunodéficience humaine (PVVIH) à Katmandou, Népal.Objectifs : Evaluer 1) les étapes du dépistage pour une recherche intensifiée de cas (ICF) de tuberculose (TB) ; 2) le traitement préventif par isoniazide (TPI), y compris les facteurs démographiques et cliniques associés à l'interruption du traitement ; et 3) la lutte contre l'infection tuberculeuse (IC) dans les structures de santé.Schéma : Etude transversale auprès des nouveaux PVVIH enrôlés entre janvier 2012 et décembre 2014.Résultats : Parmi 572 PVVIH enregistrés, 91% étaient sous traitement antirétroviral. Parmi les inscrits, 561 (98%) ont eu un dépistage de TB et 73 (13%) ont eu un diagnostic de TB (17 [25%] TB à frottis positif, 17 [25%] TB à frottis négatif et 35 [51%] TB extra-pulmonaire). Parmi les 488 (87%) PVVIH sans TB active, 157 (32%) ont été mis sous TPI, 136 (87%) d'entre eux l'ont achevé et 17 (11%) ont interrompu le traitement. Ceux qui ont eu des effets secondaires ont été 12 fois plus susceptibles d'interrompre le TPI. Les mesures de lutte contre l'infection TB connaissent des lacunes en termes de mesures de protection individuelle et des structures et des politiques de soutien.Conclusion : La mise en œuvre des Trois I pour des activités collaborative TB-VIH dans des sites pilotes au Népal s'est faite avec succès et devrait être étendue.


Marco de referencia: Los tres hospitales públicos de atención terciaria que prestan servicios a las personas aquejadas de infección por el virus de la inmunodeficiencia humana (PVVIH) en Katmandú, Nepal.Objetivos: Evaluar 1) el algoritmo de detección en la búsqueda intensiva de casos de tuberculosis (TB); 2) el tratamiento preventivo con isoniazida (TPI), incluidos los factores demográficos y clínicos que se asocian con su interrupción; y 3) el control de la infección (IC) tuberculosa en los establecimientos de salud.Método: Fue este un estudio transversal de los PVVIH recién inscritos en el programa de enero del 2012 a diciembre del 2014.Resultados: De 572 PVVIH inscritos, el 91% recibía tratamiento antirretrovírico. De los pacientes registrados, en 561 se practicó la detección sistemática de la TB (98%) y se diagnosticaron 73 casos de enfermedad activa (13%) (17 obtuvieron un resultado positivo de la baciloscopia del esputo [25%], 17 un resultado negativo [25%] y ocurrieron 35 casos de TB extrapulmonar [51%]). De los 488 PVVIH sin TB activa (87%), 157 iniciaron el TPI (32%), 136 de ellos lo completaron (87%) y 17 lo interrumpieron (11%). La probabilidad de interrumpir el TPI fue 12 veces mayor en los pacientes que presentaron reacciones adversas. Al evaluar las medidas de control de las infecciones se observaron deficiencias en las medidas personales, las estructuras auxiliares y en las normas.Conclusión: La ejecución de actividades conjuntas, los Tres I's, de atención de la TB-VIH en tres centros piloto en Nepal fue eficaz y sería muy útil ampliar su escala de aplicación.

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