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1.
J Environ Radioact ; 270: 107287, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37677908

RESUMEN

A facile modification of a strontium-based MOF using oxalic acid was carried out to prepare MTSr-OX MOF, which was used as a potential substance for eliminating 152+154Eu radioisotopes. Various analytical techniques were used to characterize MTSr-OX-MOF. The prepared MOF had a rod-like structure with a BET surface area of 101.55 m2 g-1. Batch sorption experiments were used to investigate the sorption performance of MTSr-OX-MOF towards 152+154Eu radionuclides where different parameters like pH, contact time, initial 152+154Eu concentration, ionic strength, and temperature were scrutinized to determine the optimum conditions for 152+154Eu removal. MTSr-OX-MOF showed superior effectiveness in the elimination of 152+154Eu with a maximum sorption capacity of 234.72 mg g-1 at pH 3.5. Kinetics fitted with the pseudo-second-order model and the Langmuir model correctly described the sorption mechanism. The thermodynamic variables were carefully examined, demonstrating that the 152+154Eu sorption was endothermic as well as spontaneous. The MTSr-OX-MOF has been found to be a significantly more effective sorbent towards 152+154Eu than that of many other adsorbents. When applied to real active waste, MTSr-OX-MOF demonstrated excellent removal performance for a wide range of radionuclides. As a result, the MTSr-OX-MOF can be recognized as an attractive solution for the 152+154Eu purification from active waste.


Asunto(s)
Monitoreo de Radiación , Contaminantes Químicos del Agua , Estroncio/análisis , Adsorción , Radioisótopos , Termodinámica , Cinética , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/química
2.
RSC Adv ; 13(36): 25182-25208, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37622006

RESUMEN

The nuclear industry is rapidly developing and the effective management of nuclear waste and monitoring the nuclear fuel cycle are crucial. The presence of various radionuclides such as uranium (U), europium (Eu), technetium (Tc), iodine (I), thorium (Th), cesium (Cs), and strontium (Sr) in the environment is a major concern, and the development of materials with high adsorption capacity and selectivity is essential for their effective removal. Metal-organic frameworks (MOFs) have recently emerged as promising materials for removing radioactive elements from water resources due to their unique properties such as tunable pore size, high surface area, and chemical structure. This review provides an extensive analysis of the potential of MOFs as adsorbents for purifying various radionuclides rather than using different techniques such as precipitation, filtration, ion exchange, electrolysis, solvent extraction, and flotation. This review discusses various MOF fabrication methods, focusing on minimizing environmental impacts when using organic solvents and solvent-free methods, and covers the mechanism of MOF adsorption towards radionuclides, including macroscopic and microscopic views. It also examines the effectiveness of MOFs in removing radionuclides from wastewater, their behavior on exposure to high radiation, and their renewability and reusability. We conclude by emphasizing the need for further research to optimize the performance of MOFs and expand their use in real-world applications. Overall, this review provides valuable insights into the potential of MOFs as efficient and durable materials for removing radioactive elements from water resources, addressing a critical issue in the nuclear industry.

3.
RSC Adv ; 12(21): 13103-13110, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35497013

RESUMEN

Removal of hazardous radioactive materials such as 152+154Eu from active waste using the batch approach has attracted attention nowadays. In this work, a novel melamine-terephthalic strontium metal-organic framework (MTSr-MOF) was prepared via a hydrothermal method. The MTSr-MOF was characterized by various analytical techniques such as FT-IR, 1H/13C-NMR, mass spectroscopy, XPS, XRD, TGA, BET, FE-SEM/EDX, TEM, and UV. The obtained data revealed that MTSr-MOF exhibited brick-like building blocks that were bridged together by the linkers, and each block had a thickness of ∼120 nm. The BET surface area was 74.04 m2 g-1. MTSr-MOF was used for the removal of 152+154Eu radionuclides from active waste. Further functionalization using various modifiers, including oxalic acid, EDTA, sulfuric acid, and sodium hydroxide was carried out to improve the sorption efficiency of MTSr-MOF towards 152+154Eu radionuclides. Among them, MTSr-MOF modified with oxalic acid (MTSr-OX-MOF) demonstrated a superior removal efficiency toward 152+154Eu radionuclides when compared to MTSr-MOF or other published reports, with a removal efficiency of more than 96%. The higher sorption efficiency of the MTSr-OX-MOF indicates that it could be a promising candidate for the removal of 152+154Eu radionuclides from radioactive waste.

4.
Blood Press Monit ; 27(1): 43-49, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34417374

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the left ventricular (LV) function by conventional two-dimensional speckle tracking echocardiography (2D STE) to detect subclinical LV systolic dysfunction in patients with dipper and nondipper hypertension. METHODS: One hundred consecutive patients with hypertension were included in our study. Clinical evaluation, baseline laboratory investigations, 24 ambulatory blood pressure monitoring 2D echocardiographic examination and 2D STE were performed for all patients. Patients were classified as dippers and nondippers according to their nighttime MAP (mean arterial blood pressure) reduction rate of ≥10 or <10%, respectively. RESULTS: Of 100 patients, 71% were nondippers while 29% were dippers. Nondippers had a significantly lower global longitudinal strain (LS) value (-22.45 ± 3.26 vs. -18.2 ± 3.3, P < 0.001), global circumferential strain (CS) value (-24.23 ± 3.56 vs. -19.16 ± 8.25, P < 0.001) and global radial strain (RS) value (35.04 ± 11.16 vs. 29.58 ± 8.44, P = 0.009). It was found that nondipper status was associated with worsening of LS by 2.737, (P = 0.001), CS by 3.446, (P = 0.002), RS by -3.256, (P = 0.158) and DM also was found associated with worsening of LS by 1.849, (P = 0.062), CS by 3.284 (P = 0.018), RS by -2.499 (P = 0.381). CONCLUSION: The nondipping hypertension pattern is associated with subclinical LV systolic dysfunction as shown by the impaired global myocardial strain in all three directions.


Asunto(s)
Hipertensión , Disfunción Ventricular Izquierda , Presión Sanguínea , Monitoreo Ambulatorio de la Presión Arterial , Ecocardiografía , Humanos , Hipertensión/complicaciones , Hipertensión/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen
5.
J Health Care Chaplain ; 27(2): 84-104, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-31179903

RESUMEN

Attending to patient religion and spirituality (R/S) generates controversy. Some worry that because physicians lack formal religious training they may overstep their expertise, while others argue that physicians who are attentive to patient R/S provide higher quality of care. We aimed to describe American Muslim physicians' perspectives and practices regarding R/S discussions, and how physician characteristics correlate with these.A questionnaire including measures of religiosity, empathy, and attitudes and behaviors toward R/S, was randomly administered to Islamic Medical Association of North America members.More empathetic physicians were more likely to inquire about patients' R/S, share their own religious ideas and experiences, and encourage patients in their own R/S beliefs and practices (ß = .44, p < .01). More empathetic physicians also had greater odds of encouraging discontinuation of futile life-sustaining interventions (OR 1.90, p < .05). Additionally, respondents with higher empathy had greater odds of encouraging patients at the end-of-life to seek reconciliation with God (OR 3.27, p < .001), and seek the forgiveness of those they have wronged (OR 2.48, p < .001).In the context of R/S diversity among the patient and provider population, enhancing physician empathy may be key to attending to the health-related R/S needs of patients.


Asunto(s)
Empatía , Islamismo , Relaciones Médico-Paciente , Médicos/psicología , Espiritualidad , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Médicos/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto Joven
6.
Sci Total Environ ; 708: 135159, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31810672

RESUMEN

There has been increasing focus on the resilience and sustainability of Urban Water Systems (UWS) due to the increase in urban population and rise of imminent threats (e.g. floods). This focus has brought about numerous studies attempting to develop a framework of assessment of UWS that can be benchmarked and adopted by different jurisdictions. The use of composite indicators has been the most common approach in many of the studies appearing in the past two decades. While there seems to be a consensus on the relevant technical and economic indicators in assessing UWS, the situation is different when it comes to social and institutional indicators. In this paper, a discussion of the most common institutional and social indicators used in conducting a sustainability or resilience assessment of UWS is presented. A framework of criteria which describes four key ways for ensuring that indicators are appropriate for use in UWS is proposed. The framework is described as a tool to mitigate common challenges in the development and evaluation of institutional and social indicators. While social and institutional indicators have been used in a variety of studies, the framework offers a way to better ensure that regardless of the chosen indicators, they are developed and used in a way that is consistent with the merits of social research, notably reliability and validity.

7.
Physiol Behav ; 214: 112762, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31786271

RESUMEN

BACKGROUND AND AIM: Disturbance of gut microbiota plays a role in induction and progression of non alcoholic steatohepatitis (NASH) and the associated cognitive dysfunction. We supposed that high fat diet (HFD)-induced dysbiosis may lead to NASH/cognitive impairment co-morbidities through hippocampal TLR4/BDNF signaling pathway and the regaining of microbiota balance through probiotics could provide a therapeutic option. METHODOLOGY: Four groups of male Wister rats were used; Naïve, Lactobacillus Plantarum EMCC-1039 (LP EMCC-1039), NASH and NASH+ LP EMCC-1039 groups. After induction of NASH with high fat diet (HFD), LP EMCC-1039 was given daily by oral gavage in the last two weeks of experiment to the treated group. Body weight percentage (BW%) changes, Lee index (LI), liver function tests, expression of BDNF, TLR4 with RT-PCR and quantification of BDNF, TLR4 by ELISA were measured . Histological studies and assessment of cognitive function were also performed. RESULTS: NASH group showed an increase in BW% and LI . It was associated with cognitive deficits, an increase in hepatic, hippocampal TLR4 expression and decline in BDNF expression and protein, all p values were <0.05. Histological examination revealed significant decrease in number of viable cells and shrinking of pyramidal cells in hippocampus (p<0.05). Treatment with LP EMCC-1039 improved all these pathological changes significantly (p<0.05) with negative correlation between NAFLD activity score (NAS) and cognitive measurements. Additionally, hepatic and hippocampal TLR4 expression were decreased and BDNF expression and quantity were increased. CONCLUSIONS: Dysbiosis-induced NASH was associated with cognitive impairment and a probiotic (LP EMCC-1039) supplementation has beneficial effect through modulation of TLR4/BDNF signaling pathway.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Disfunción Cognitiva/dietoterapia , Dieta Alta en Grasa/efectos adversos , Enfermedad del Hígado Graso no Alcohólico/dietoterapia , Probióticos/uso terapéutico , Receptor Toll-Like 4/biosíntesis , Animales , Disfunción Cognitiva/microbiología , Disbiosis/inducido químicamente , Hipocampo/metabolismo , Pruebas de Función Hepática , Masculino , Enfermedad del Hígado Graso no Alcohólico/inducido químicamente , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Ratas , Transducción de Señal/fisiología
8.
Gene ; 707: 198-204, 2019 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-31075409

RESUMEN

BACKGROUND: Drug-induced kidney injury (DIKI) can be manifested with progressive chronic kidney diseases or end-stage renal diseases. Understanding the molecular disarrangements caused by DIKI is an attractive point of interest. A class of non-coding RNA called microRNAs (miRNAs) is known to play a major role in regulation of gene expression and signaling pathways making miRNAs excellent targets for new therapeutic agents. AIM OF THE STUDY: We aimed to investigate the role of miRNA 21 and 181a in gentamicin (GNT) induced nephrotoxicity rat model and the protective effect of Dapagliflozin (DAPA) in modulating their expression through studying its effect on renal function as well as renal histopathological changes. MATERIALS AND METHODS: Wistar rats were used and divided into: naïve, DAPA, GNT and DAPA + GNT groups. In all studied groups, kidney function, oxidative stress, apoptosis markers and miRNAs' expression in serum and renal biopsies were investigated in addition to the histopathological studies to identify its early renoprotective effect. RESULTS: DAPA was found to improve kidney function, oxidative stress markers, decrease apoptosis of renal tubular cells and increase miR-21 but decrease the expression of miR-181a with restoration of the renal architecture after 14 days of treatment in GNT induced nephrotoxicity rat model. CONCLUSIONS: DAPA produced significant decrease in renal expression of miR-181a on the other hand it increased the expression of renal miR-21, this may introduce a novel early protective effect of DAPA against GNT-induced nephrotoxicity.


Asunto(s)
Lesión Renal Aguda/tratamiento farmacológico , Compuestos de Bencidrilo/administración & dosificación , Gentamicinas/efectos adversos , Glucósidos/administración & dosificación , MicroARNs/genética , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/genética , Lesión Renal Aguda/fisiopatología , Animales , Apoptosis/efectos de los fármacos , Compuestos de Bencidrilo/farmacología , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Glucósidos/farmacología , Pruebas de Función Renal , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar
9.
Sci Total Environ ; 645: 993-1002, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30248886

RESUMEN

Quantitative microbial risk assessment (QMRA) has been mainstreamed in many large municipal water systems as part of a paradigm shift in the drinking water industry towards water safety planning and risk-based system assessment. Small water systems (SWSs) are generally more vulnerable to typical water system hazards, and consequently have a higher risk of waterborne disease outbreak. In this paper, a review of experiences in implementing QMRA in SWSs helps elaborate the sources of risks and highlights some of the challenges facing SWSs in developed countries. A critical review of the important elements for practical implementation of QMRA was conducted. The investigation focuses on aspects related to challenges in identifying relevant hazards to SWSs to create failure scenarios, acquiring monitoring data for pathogens' concentrations in source water, estimating treatment efficiencies of typical small system technologies, and access to software tools to support successful implementation. The review helped outline ways through which SWSs can overcome the identified challenges in implementing QMRA. An adjusted framework for implementing QMRA for small water systems was formulated and discussed.


Asunto(s)
Monitoreo del Ambiente , Microbiología del Agua , Abastecimiento de Agua/estadística & datos numéricos , Agua Potable , Modelos Teóricos , Medición de Riesgo
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