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1.
Environ Res ; 238(Pt 1): 117133, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37729960

RESUMO

Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issue. In case of any nuclear accident, there is a great need to mitigate the radioactive organic iodide immediately as it accumulates in human bodies, causing severe consequences. Current research focuses on removing organic iodides, for which the surface of activated carbon (AC) was modified by impregnating it with different metals individually, i.e. Ag, Ni, Zn, Cu and with the novel combination of these four metals (AZNC). After the impregnation of metals, triethylenediamine (TEDA) was coated on metal impregnated activated carbon (IAC) surface. The adsorption capacity of the combination of four metals IAC was found to be 276 mg/g as the maximum for the trapping of CH3I. Whereas TEDA-metal impregnation on ACs enhanced the removal efficiency of CH3I up to 352 mg/g. After impregnation, adsorption capacity of AZNC and AZNCT is significantly higher as compared to AC. According to the finding, t5% of AZNCT IAC is 46 min, which is considerably higher than the t5% of other tested adsorbents. According to isotherm fitting data, Langmuir isotherm was found superior for describing CH3I sorption onto AC and IACs. Kinetics study shows that pseudo second order model represented the sorption of CH3I more accurately than the pseudo first order. Thermodynamic studies gave negative value of ΔG which shows that the reaction is spontaneous in nature. Based on the findings, AZNCT IAC appears to have a great potential for air purification applications in order to obtain clean environment.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Humanos , Metais , Piperazinas , Adsorção , Cinética , Concentração de Íons de Hidrogênio
2.
Environ Monit Assess ; 195(7): 851, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37326918

RESUMO

Measurements of radionuclides' activities in air, water, and soil give clues about the anthropogenic activities in the region, and imperative to assess the overall radiological risk for individuals. Such an investigation was carried out to characterize the soil activities in the region hosting a research center, and to calculate the associated elements of radiological risk in terms of radiation doses and hazard indices. The soil samples were collected within the radius of 10 km in local area, Nilore, and analysed for activity using a high-purity germanium (HPGe) gamma spectrometric system. In all samples, only the basic nuclides, contributing to terrestrial activity, i.e., 40 K, 232Th, 226Ra, and 137Cs, were observed within the detectable limits of activity. The distribution of the data set and the correlation between the measured activities were studied with the use of the principal component analysis (PCA). The measured average specific activities of 226Ra, 232Th, 40 K, and 137Cs were 40.65 ± 9.84 Bq/kg, 59.31 ± 16.53 Bq/kg, 528.24 ± 131.18 Bq/kg, and 5.16 ± 4.56 Bq/kg respectively. The corresponding dose rate in air was found to be 76.63 ± 18.39 nGy/h, which is slightly higher than the world median value of 51 nGy/h calculated from concentration of terrestrial radionuclides in soil but falls within the world average value range of outdoor external exposure of 18-93 nGy/h obtained through direct measurement, and therefore not harmful for the living species. The standard hazard indices for all soil samples such as radium equivalent activity ([Formula: see text]), external hazard index (Hex), and internal hazard index (Hin) were also found within safe limits for the soil to be used as construction of building material. This investigation led to conclusion that the soil activities are consistent with the usual background level of terrestrial activities, and their associated dose rates are well within the safe limits for public.


Assuntos
Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Humanos , Espectrometria gama , Monitoramento de Radiação/métodos , Paquistão , Poluentes Radioativos do Solo/análise , Radioisótopos de Césio/análise , Rádio (Elemento)/análise , Solo/química , Medição de Risco , Tório/análise , Radioisótopos de Potássio/análise
3.
Environ Sci Pollut Res Int ; 30(30): 74628-74670, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37231136

RESUMO

Radioactive iodine is a hazardous fission product and a major concern for public health. Special attention is paid to iodine out of 80 fission products because of its short half-life of 8.02 days, high activity, and potential health hazards like its irreversible accumulation in thyroid gland and ability to cause thyroid cancer locally. Radioactive iodine can get released in the form of aerosols (cesium iodide), elemental iodine, and organic iodide after a nuclear accident and can cause off-site and on-site contamination. Filtered containment venting system (FCVS) is a safety system whose main objective is mitigation of severe accidents via controlled venting and removal of different forms of iodine to ensure safety of people and environment. After nuclear accidents like Fukushima, extensive research has been done on the removal of iodine by using dry scrubbers. This review paper presents research status of iodine removal by dry adsorbents especially after 10 years of Fukushima to assess the progress, research gap, and challenges that require more attention. A good adsorbent should be cost-effective; it should have high selective adsorption towards iodine, high thermal and chemical stability, and good loading capacity; and its adsorption should remain unaffected by aging and the presence of inhibitors like CO, NO2, CH3Cl, H2O, and Cl2 and radiation. Research on different dry adsorbents was discussed, and their capability as a potential filter for FCVS was reviewed on the basis of all the above-mentioned features. Metal fiber filters have been widely used for removal of aerosols especially micro- and nanoscale aerosols. For designing a metal fiber filter, optimal size or combination of sizes of fibers, number of layers, and loading capacity of filter should be decided according to feasibility and requirement. Balance between flow resistance and removal efficiency is also very important. Sand bed filters were successful in retention of aerosols, but they showed low trapping of iodine and no trapping of methyl iodide at all. For iodine and methyl iodide removal, many adsorbents like activated carbon, zeolites, metal organic frameworks (MOFs), porous organic frameworks (POPs), silica, aerogels, titanosilicates, etc. have been used. Impregnated activated carbon showed good results but low auto-ignition temperature and decline in adsorption due to aging and inhibitors like NOx made them less suitable. Silver zeolites have been very successful in methyl iodide and iodine removal, but they are expensive and affected by presence of CO. Titanosilicates, macroreticular resins, and chalcogels were also studied and they showed good adsorption capacities, but their thermal stability was low. Other adsorbents like silica, MOFs, aerogels, and POPs also showed promising results for iodine adsorption and good thermal stability, but very limited or no research is available on their performance in severe accident conditions. This review will be very helpful for researchers to understand the merits and demerits of different types of dry adsorbents, the important operating parameters that need optimization for designing an efficient scrubber, margin of research, and foreseeable challenges in removal of different forms of iodine.


Assuntos
Acidente Nuclear de Fukushima , Iodo , Neoplasias da Glândula Tireoide , Zeolitas , Humanos , Radioisótopos do Iodo , Carvão Vegetal , Adsorção
4.
Chemosphere ; 316: 137878, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36646179

RESUMO

There is a dire need of air quality monitoring in the high-mountain areas of Karakoram-Hindu Kush-Himalaya (HKH) region, particularly related to the recent activities undergoing the China-Pakistan Economic Corridor (CPEC). This study presents the first baseline monitoring and evaluation findings from Gilgit city, Gilgit-Baltistan. Hourly data collection for air quality parameters (PM2.5, NO, NO2, SO2, O3 and CO) were measured using air-pointer (recordum, Austria) from 1 Jan 2018 to 31 Mar 2018 (winter) and 1 Jun 2018 to 31 Aug 2018 (summer). Our findings depict PM2.5 health limits were crossed in the winter season, while NO, NO2 and SO2 remained below their health limits. O3 and CO showed a rising trend in summer months, crossing the 8-h health limits during the season. Seasonal correlation in meteorology found an inverse relationship between most parameters and temperatures; reverse was true for O3 and CO. In parallel, thermal optical carbon analysis filter-based sampling characterized air quality into mass concentrations of PM2.5, organic carbon (OC), elemental carbon (EC) and various heavy metals. Filter-based PM2.5 correlated well with analyzer-based PM2.5 for all months that were studied, except February and March 2018. PM2.5, OC and EC were higher in summer as compared to winter, whereas higher heavy metal contributions were measured predominantly during summer. Health impacts were found to be above health limits for Ni in children only. Furthermore, principal component analysis-multiple linear regression (PCA-MLR) technique was applied to determine source apportionment, confirming the role of biomass burning in winters, and vehicular emissions in summers, highlighting the need for flexible monitoring of technologies/approaches, and communications among the various public, private agencies, and all relevant stakeholders.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Criança , Humanos , Poluentes Atmosféricos/análise , Estações do Ano , Material Particulado/análise , Dióxido de Nitrogênio/análise , Paquistão , Monitoramento Ambiental/métodos , Poluição do Ar/análise , Emissões de Veículos/análise , Carbono/análise , Aerossóis/análise
5.
Sensors (Basel) ; 22(3)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35161665

RESUMO

Cloud computing has emerged as the most favorable computing platform for researchers and industry. The load balanced task scheduling has emerged as an important and challenging research problem in the Cloud computing. Swarm intelligence-based meta-heuristic algorithms are considered more suitable for Cloud scheduling and load balancing. The optimization procedure of swarm intelligence-based meta-heuristics consists of two major components that are the local and global search. These algorithms find the best position through the local and global search. To achieve an optimized mapping strategy for tasks to the resources, a balance between local and global search plays an effective role. The inertia weight is an important control attribute to effectively adjust the local and global search process. There are many inertia weight strategies; however, the existing approaches still require fine-tuning to achieve optimum scheduling. The selection of a suitable inertia weight strategy is also an important factor. This paper contributed an adaptive Particle Swarm Optimisation (PSO) based task scheduling approach that reduces the task execution time, and increases throughput and Average Resource Utilization Ratio (ARUR). Moreover, an adaptive inertia weight strategy namely Linearly Descending and Adaptive Inertia Weight (LDAIW) is introduced. The proposed scheduling approach provides a better balance between local and global search leading to an optimized task scheduling. The performance of the proposed approach has been evaluated and compared against five renown PSO based inertia weight strategies concerning makespan and throughput. The experiments are then extended and compared the proposed approach against the other four renowned meta-heuristic scheduling approaches. Analysis of the simulated experimentation reveals that the proposed approach attained up to 10%, 12% and 60% improvement for makespan, throughput and ARUR respectively.


Assuntos
Algoritmos , Computação em Nuvem , Heurística , Indústrias
6.
Environ Sci Pollut Res Int ; 29(20): 30311-30323, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34997487

RESUMO

In order to provide protection against extremely toxic gases, activated carbon (AC) adsorption has long been regarded to be a useful technology in terms of gas removal. AC without chemical impregnation has been considerably less effective than impregnated ACs. AC in present use was modified with an organic amine, i.e., triethylenediamine (TEDA) to enhance the physical and chemical properties of AC in order to remove specific poisonous gases. With the rising concern on environmental pollution, there has been an increased curiosity in ACs as the means for eliminating pollutants from environment. Purpose of this study was to assess the TEDA impregnated AC in terms of adsorption capability for simulant gas like SO2. Analysis was done in a properly designed setup. By using the scheme reported here, significant adsorption of toxic gas was obtained. Maximum removal capability observed by AC-4 for SO2 gas was 374 mg/g-C and its breakthrough time was 264 min. Breakthrough time and adsorption capacity of AC-4 was found to be 25 times and 10 times greater as compared to raw AC. Different characterization techniques were also used to study impregnated AC. It was found that chemical adsorption was the crucial means by which TEDA-impregnated AC removed the simulant gas. Langmuir model was best to represent equilibrium, and adsorption kinetics follow second-order model. The process was endothermic, favorable, and spontaneous.


Assuntos
Dióxido de Enxofre , Poluentes Químicos da Água , Adsorção , Carvão Vegetal/química , Cinética , Piperazinas/química , Dióxido de Enxofre/química
7.
Environ Sci Pollut Res Int ; 28(43): 60477-60494, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34545527

RESUMO

Nuclear, biological, and chemical warfare (NBC) agents cause an inevitable threat to defense forces and civilians. Exposure to these toxic agents causes a lot of damage to lives. One can avoid the damage of these toxic agents by taking appropriate preventive measures. Respiratory protection is obviously necessary when military personnel or civilians get bounded by such type of noxious situation as contaminant-free air is then required for breathing and it can only be provided by means of a proper gas mask and relevant canister. In purification of contaminated atmospheres, activated carbon has so far met with outstanding success. It removes toxic chemicals either by chemical or physical adsorption from the contaminated air. When any toxic chemicals get adsorbed on the modified impregnated carbon's surface, they usually adsorb there by means of chemical reactions. Destruction of adsorbed toxic substances is expected by such a reactive carbon. In this perspective, an attempt has been made to review the literature from past decades on the removal of toxic chemical warfare agents (CWAs) and radioactive content from air stream in case of any nuclear, biological, and chemical attack by selectively modifying or impregnating the activated carbon surface. This review also covers some important adsorption properties of materials being used in gas mask filters for effective removal of chemicals from airstream. The probable removal mechanisms of various chemical warfare agents and radioactive content have also been reviewed.


Assuntos
Poluição do Ar , Substâncias para a Guerra Química , Adsorção , Atmosfera , Carvão Vegetal , Substâncias para a Guerra Química/análise
8.
Natl J Maxillofac Surg ; 10(2): 134-140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798246

RESUMO

INTRODUCTION: Health-related quality of life (HRQoL) is a more specific area of QoL that deals with the evaluation and assessment of the impact of the disease and its treatment-related morbidities on a patient's physical, psychological, and social aspects. The aim of the present study was to assess the HRQoL of patients with head-and-neck cancer (HNCs) during and at 3 months after completion of radiotherapy (RT) by intensity-modulated RT. MATERIALS AND METHODS: This study was a prospective, longitudinal, observational, and self-completed questionnaire-based study that included 120 patients with HNC who underwent intensity-modulated RT. The questionnaire had adequate internal consistency. The questionnaires were given to each patient at the beginning of treatment (pretreatment), weekly visits during the course of RT (at the end of 1st, 2nd, 3rd, 4th, 5th, and 6th week), on the day of completion of RT, and then finally at 3 months after completion of RT. Thus, a total of successive nine time points were assessed. RESULTS AND CONCLUSIONS: One hundred and eleven patients completed the questionnaires at all nine time points. HRQoL usually decreases during treatment and then increases to pretreatment levels by 3 months after treatment. The Quality of Life Questionnaire, Core Module and Quality of Life Questionnaire, Head and Neck Module were found to be both valid and reliable. There was a significant QoL reduction for the patients throughout treatment in relation to functions and symptoms in the treatment of HNC. However, all the functions and most of the symptoms returned to baseline at the 3-month follow-up.

9.
J Environ Radioact ; 205-206: 34-41, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31096106

RESUMO

In this paper the mesoscale application of the 3D Lagrangian particle dispersion model LAPMOD has been assessed for a field tracer test performed in a short-range complex terrain. The meteorological input was provided through the diagnostic model CALMET, the meteorological pre-processor of the CALPUFF model. The CALMET/LAPMOD coupled system was used to simulate the hourly averaged ground level concentration at 47 discrete receptors. The LAPMOD model has a general tendency to slightly underestimate the hourly averaged ground-level concentrations. A Q-Q plot shows that the predicted concentration distribution has a good comparison with observed one. The Robust Highest Concentration (RHC) indicates that the LAPMOD model slightly underestimates the simulated peak concentration in short-term release conditions. The Fractional Bias (FB), Normalized Mean Squared Error (NMSE), Factor of Two (FAC2), Factor of Four (FAC4) and Factor of Exceedance (FOEX) statistical indices were calculated. The predicted results by LAPMOD are generally in good agreement with observed ones and the model is justified for the use in complex terrain for short-term near-field applications.


Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação/métodos , Movimentos do Ar , Geografia , Modelos Teóricos
10.
Autophagy ; 15(10): 1810-1828, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30894052

RESUMO

Imbalance in production and clearance of amyloid beta (Aß) is the primary reason for its deposition in Alzheimer disease. Macroautophagy/autophagy is one of the important mechanisms for clearance of both intracellular and extracellular Aß. Here, through screening, we identified alborixin, an ionophore, as a potent inducer of autophagy. We found that autophagy induced by alborixin substantially cleared Aß in microglia and primary neuronal cells. Induction of autophagy was accompanied by up regulation of autophagy proteins BECN1/Beclin 1, ATG5, ATG7 and increased lysosomal activities. Autophagy induced by alborixin was associated with inhibition of the phosphoinositide 3-kinase (PI3K)-AKT pathway. A knock down of PTEN and consistent, constitutive activation of AKT inhibited alborixin-induced autophagy and consequent clearance of Aß. Furthermore, clearance of Aß by alborixin led to significant reduction of Aß-mediated cytotoxicity in primary neurons and differentiated N2a cells. Thus, our findings put forward alborixin as a potential anti-Alzheimer therapeutic lead. Abbreviations: Aß: amyloid beta; ALB: alborixin; ATG: autophagy-related; BECN1: beclin 1; DAPI: 4, 6-diamidino-2-phenylindole; DCFH-DA: 2,7-dichlorodihydrofluorescein diacetate; fAß: fibrillary form of amyloid beta; GFAP: glial fibrillary acidic protein; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; MAP2: microtubule-associated protein 2; MTOR: mechanistic target of rapamycin kinase; PTEN: phosphatase and tensin homolog; ROS: reactive oxygen species; SQSTM1: sequestosome 1; TMRE: tetramethylrhodamine, ethyl ester.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Autofagia/efeitos dos fármacos , PTEN Fosfo-Hidrolase/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Peptídeos beta-Amiloides/efeitos dos fármacos , Animais , Autofagia/fisiologia , Células Cultivadas , Embrião de Mamíferos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , PTEN Fosfo-Hidrolase/genética , Proteólise/efeitos dos fármacos , Piranos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
11.
Head Neck ; 41(6): 1632-1637, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30582238

RESUMO

BACKGROUND: Labeling locoregional failures in head and neck cancer (HNC) as "local" and "regional" becomes incomplete when treating with intensity modulated radiotherapy (IMRT). Target delineation and delivery errors, dose in-homogeneity complicate the assessment of failures. A combination of focal point and dosimetric method might attempt at simplifying failure analysis. METHODS: One hundred eleven patients with locally advanced HNC treated with chemoradiation using IMRT were enrolled. Patients with documented failure had their recurrence volume assessed using focal point and dosimetric method. RESULTS: With a median follow-up of 20 (range 0-39) months and median locoregional control (LRC) of 30 (range 24.8-34.5) months, the patients had a 3-year overall survival and LRC of 70.6% and 48.9%, respectively. Of 39 failures, there were 69.2%, 7.6%, 5.1%, 12.8%, and 5.1% type A, B, C, D, and E, respectively using the focal point and dosimetric method. CONCLUSION: With the current classification, majority of the recurrences were high dose failures suggesting inherent radioresistance. While minority of failures were potentially preventable and needed modifying existing IMRT workflow.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Radiometria/métodos , Radioterapia de Intensidade Modulada , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/mortalidade , Quimiorradioterapia , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Prospectivos , Falha de Tratamento , Adulto Jovem
12.
Lung India ; 35(1): 54-57, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29319036

RESUMO

This is a case report of a 60-year-old diabetic, hypertensive male with a good performance status and a history of bilateral interstitial lung disease with a left upper lobe lung mass diagnosed to be a Stage IIB mixed small-cell/squamous cell carcinoma which was refractory to carboplatin- and etoposide-based chemotherapy. The patient was then taken up for adaptive intensity-modulated radiotherapy with tighter margin under image guidance with a mid-treatment replanning done at 25#. Acute toxicities were assessed weekly and showed no Grade 3 or more reactions. Pulmonary function test showed no detrimental changes during or after radiation. Response assessment at 12 and 20 weeks showed a partial response with decrease in metabolic activity on serial scans.

13.
Sci Rep ; 6: 33146, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27680387

RESUMO

In this study, we investigated the role of autophagy induced by boswellic acid analog BA145 on cell cycle progression in pancreatic cancer cells. BA145 induced robust autophagy in pancreatic cancer cell line PANC-1 and exhibited cell proliferation inhibition by inducing cells to undergo G2/M arrest. Inhibition of G2/M progression was associated with decreased expression of cyclin A, cyclin B, cyclin E, cdc2, cdc25c and CDK-1. Pre-treatment of cells with autophagy inhibitors or silencing the expression of key autophagy genes abrogated BA145 induced G2/M arrest and downregulation of cell cycle regulatory proteins. It was further observed that BA145 induced autophagy by targeting mTOR kinase (IC50 1 µM), leading to reduced expression of p-mTOR, p-p70S6K (T389), p-4EBP (T37/46) and p-S6 (S240/244). Notably, inhibition of mTOR signalling by BA145 was followed by attendant activation of AKT and its membrane translocation. Inhibition of Akt through pharmacological inhibitors or siRNAs enhanced BA145 mediated autophagy, G2/M arrest and reduced expression of G2/M regulators. Further studies revealed that BA145 arbitrated inhibition of mTOR led to the activation of Akt through IGFR/PI3k/Akt feedback loop. Intervention in IGFR/PI3k/Akt loop further depreciated Akt phosphorylation and its membrane translocation that culminates in augmented autophagy with concomitant G2/M arrest and cell death.

14.
J Pak Med Assoc ; 65(9): 990-4, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26338747

RESUMO

OBJECTIVE: To assess the knowledge of lady health visitors and midwives working at primary healthcare facilities about neonatal resuscitation. METHODS: The cross-sectional survey was conducted in District Sheikhupura of Pakistan's Punjab province from September to November 2013, and comprised lady health visitors and midwives at primary level healthcare facilities. Datas was gathered using a close-ended questionnaire. SPSS 16 was used for statistical analysis. RESULTS: Of the 103 health workers interviewed, 54(52.4%) were lady health visitors and 49(47.5%) were midwives. Overall, 71(69.90%) health workers had received training on neonatal resuscitation, while 32(30.10%) had no formal training. Basic neonatal resuscitative arrangements were available at all the 54(100%) basic health units and 7(100%) rural health centres. Basic neonatal care knowledge was found adequate but the knowledge of midwives on the subject was poor as only 24(49%) answered correctly. CONCLUSIONS: There is a need for regular in-service trainings of lady health visitors and midwives regarding Basic Neonatal Resuscitation.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Cuidado do Lactente/normas , Tocologia , Enfermeiros de Saúde Comunitária , Atenção Primária à Saúde , Ressuscitação/normas , Adulto , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Paquistão , Inquéritos e Questionários
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