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1.
Bioengineering (Basel) ; 11(8)2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39199801

RESUMEN

This study aimed to investigate whether plaque characteristics derived from intravascular optical coherence tomography (IVOCT) could predict a long-term cardiovascular (CV) death. This study was a single-center, retrospective study on 104 patients who had undergone IVOCT-guided percutaneous coronary intervention. Plaque characterization was performed using Optical Coherence TOmography PlaqUe and Stent (OCTOPUS) software developed by our group. A total of 31 plaque features, including lesion length, lumen, calcium, fibrous cap (FC), and vulnerable plaque features (e.g., microchannel), were computed from the baseline IVOCT images. The discriminatory power for predicting CV death was determined using univariate/multivariate logistic regressions. Of 104 patients, CV death was identified in 24 patients (23.1%). Univariate logistic regression revealed that lesion length, calcium angle, calcium thickness, FC angle, FC area, and FC surface area were significantly associated with CV death (p < 0.05). In the multivariate logistic analysis, only the FC surface area (OR 2.38, CI 0.98-5.83, p < 0.05) was identified as a significant determinant for CV death, highlighting the importance of the 3D lesion analysis. The AUC of FC surface area for predicting CV death was 0.851 (95% CI 0.800-0.927, p < 0.05). Patients with CV death had distinct plaque characteristics (i.e., large FC surface area) in IVOCT. Studies such as this one might someday lead to recommendations for pharmaceutical and interventional approaches.

2.
Environ Sci Pollut Res Int ; 31(35): 47655-47673, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39003426

RESUMEN

Phytoremediation is an in situ remediation and eco-friendly technique employing accumulator plant species to remove trace elements (TEs) from contaminated sites. Moreover, it has been demonstrated that both natural and synthetic amendments can enhance trace elements (TEs) phytoremediation from polluted soils through bioenergy crops. This work assessed the synergistic impact of two tested biochar (BC) from data palm (B1) and Prosopis (B2) (1.5%/ kg), citric acid (CA, 1.5 mmol/kg) and vermiwash (VW, 20 ml/kg) to enhance the remediation of tested TEs (Mn, Zn, Cd, Pb, Ni, Cu, and Fe) from Mahad AD'Dahab mine-contaminated soil by sorghum (Sorghum bicolor L.). The BC and CA amendments alone and combined with VW significantly augmented the proliferation and survival of sorghum grown in mine-contaminated soil. Considering the individual and combined applications of VW and BC, the influence on plant growth followed this order: K < VW < B2 < B1 < B1 + VW < B2 + VW < CA < CA + VW. Applying tested BC/CA and VW significantly increased chlorophyll compared to unamended soil. The outcomes revealed a substantial elevation in TE absorption in both shoot and root (p ≤ 0.05) with all tested treatments compared to the untreated soil (K). The combined application of CA and VW resulted in the most significant TE uptake of TEs at both the root and the shoot. Furthermore, adding CA or VW as a foliar spray enhanced the bioaccumulation factor (BCF) and translocation factor (TF) of studied metals. The combined addition of CA and foliar spraying of VW was more effective than the sole addition of CA or VW. Such increase reached 20.0%, 15.6%, 19.4%, 14.3%, 14.0%, and 25.6% of TF, and 13.7%, 11.9%, 8.3%, 20.9%, 20.5%,18.7%, and 19.8% of BCE for Cd, Cu, Fe, Mn, Ni, Pb, and Zn, respectively. This study highlights the efficiency of combining CA/BC with VW as a more viable option for remediating mine-contaminated soil than individual amendments. However, future research should prioritize long-term field trials to assess the efficiency of using citric acid and vermiwash for restoring contaminated mining soils.


Asunto(s)
Biodegradación Ambiental , Carbón Orgánico , Ácido Cítrico , Minería , Contaminantes del Suelo , Suelo , Sorghum , Carbón Orgánico/química , Ácido Cítrico/química , Suelo/química , Restauración y Remediación Ambiental/métodos
3.
Resuscitation ; 201: 110264, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38851447

RESUMEN

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is associated with low survival rates. Bystander cardiopulmonary resuscitation (CPR) is essential for improving outcomes, but its utilization remains limited, particularly among racial and ethnic minorities. Historical redlining, a practice that classified neighborhoods for mortgage risk in 1930s, may have lasting implications for social and health outcomes. This study sought to investigate the influence of redlining on the provision of bystander CPR during witnessed OHCA. METHODS: We conducted an analysis using data from the comprehensive Cardiac Arrest Registry to Enhance Survival (CARES), encompassing 736,066 non-traumatic OHCA cases across the United States. The Home Owners' Loan Corporation (HOLC) map shapefiles were utilized to categorize census tracts of arrests into four grades (A signifying "best", B "still desirable", C "declining", and D "hazardous"). Multivariable hierarchical logistic regression models were employed to predict the likelihood of CPR provision, adjusting for various factors including age, sex, race/ethnicity, arrest location, calendar year, and state of occurrence. Additionally, we accounted for the percentage of Black residents and residents below poverty levels at the census tract level. RESULTS: Among the 43,186 witnessed cases of OHCA in graded HOLC census tracts, 37.2% received bystander CPR. The rates of bystander CPR exhibited a gradual decline across HOLC grades, ranging from 41.8% in HOLC grade A to 35.8% in HOLC grade D. In fully adjusted model, we observed significantly lower odds of receiving bystander CPR in HOLC grades C (OR 0.89, 95% CI 0.81-0.98, p = 0.016) and D (OR 0.86, 95% CI 0.78-0.95, p = 0.002) compared to HOLC grade A. CONCLUSION: Redlining, a historical segregation practice, is associated with reduced contemporary rates of bystander CPR during OHCA. Targeted CPR training in redlined neighborhoods may be imperative to enhance survival outcomes.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , Humanos , Paro Cardíaco Extrahospitalario/terapia , Paro Cardíaco Extrahospitalario/mortalidad , Reanimación Cardiopulmonar/estadística & datos numéricos , Reanimación Cardiopulmonar/métodos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Estados Unidos/epidemiología , Sistema de Registros , Disparidades en Atención de Salud/estadística & datos numéricos , Características del Vecindario/estadística & datos numéricos , Características de la Residencia/estadística & datos numéricos , Servicios Médicos de Urgencia/estadística & datos numéricos
4.
Curr Probl Cardiol ; 49(6): 102565, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38599559

RESUMEN

Lead exposure has been linked to a myriad of cardiovascular diseases. Utilizing data from the 2019 Global Burden of Disease Study, we quantified age-standardized lead exposure-related mortality and disability-adjusted life years (DALYs) in the United States between 1990 and 2019. Our analysis revealed a substantial reduction in age-standardized cardiovascular disease (CVD) mortality attributable to lead exposure by 60 % (from 7.4 to 2.9 per 100,000), along with a concurrent decrease in age-standardized CVD DALYs by 66 % (from 143.2 to 48.7 per 100,000).


Asunto(s)
Enfermedades Cardiovasculares , Plomo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/mortalidad , Costo de Enfermedad , Años de Vida Ajustados por Discapacidad , Exposición a Riesgos Ambientales/efectos adversos , Carga Global de Enfermedades , Plomo/efectos adversos , Intoxicación por Plomo/epidemiología , Intoxicación por Plomo/diagnóstico , Factores de Riesgo , Estados Unidos/epidemiología
5.
Sci Rep ; 14(1): 4393, 2024 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388637

RESUMEN

Thin-cap fibroatheroma (TCFA) is a prominent risk factor for plaque rupture. Intravascular optical coherence tomography (IVOCT) enables identification of fibrous cap (FC), measurement of FC thicknesses, and assessment of plaque vulnerability. We developed a fully-automated deep learning method for FC segmentation. This study included 32,531 images across 227 pullbacks from two registries (TRANSFORM-OCT and UHCMC). Images were semi-automatically labeled using our OCTOPUS with expert editing using established guidelines. We employed preprocessing including guidewire shadow detection, lumen segmentation, pixel-shifting, and Gaussian filtering on raw IVOCT (r,θ) images. Data were augmented in a natural way by changing θ in spiral acquisitions and by changing intensity and noise values. We used a modified SegResNet and comparison networks to segment FCs. We employed transfer learning from our existing much larger, fully-labeled calcification IVOCT dataset to reduce deep-learning training. Postprocessing with a morphological operation enhanced segmentation performance. Overall, our method consistently delivered better FC segmentation results (Dice: 0.837 ± 0.012) than other deep-learning methods. Transfer learning reduced training time by 84% and reduced the need for more training samples. Our method showed a high level of generalizability, evidenced by highly-consistent segmentations across five-fold cross-validation (sensitivity: 85.0 ± 0.3%, Dice: 0.846 ± 0.011) and the held-out test (sensitivity: 84.9%, Dice: 0.816) sets. In addition, we found excellent agreement of FC thickness with ground truth (2.95 ± 20.73 µm), giving clinically insignificant bias. There was excellent reproducibility in pre- and post-stenting pullbacks (average FC angle: 200.9 ± 128.0°/202.0 ± 121.1°). Our fully automated, deep-learning FC segmentation method demonstrated excellent performance, generalizability, and reproducibility on multi-center datasets. It will be useful for multiple research purposes and potentially for planning stent deployments that avoid placing a stent edge over an FC.


Asunto(s)
Aprendizaje Profundo , Placa Aterosclerótica , Humanos , Tomografía de Coherencia Óptica/métodos , Reproducibilidad de los Resultados , Vasos Coronarios/patología , Placa Aterosclerótica/diagnóstico por imagen , Placa Aterosclerótica/patología , Fibrosis
8.
Local Environ ; 28(4): 518-528, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37588138

RESUMEN

To stabilize the housing market during the great depression, the government-sanctioned Home Owners' Loan Corporation (HOLC) created color coded maps of nearly 200 United States cities according to lending risk. These maps were largely driven by racial segregation, with the worst graded neighborhoods colored in red, later termed redlined neighborhoods. We sought to investigate the association between historical redlining, and trends in environmental disparities across the US over the past few decades. We characterized environmental exposures including air pollutants (e.g., NO2 and fine particulate matter), vegetation, noise, and light at night, proximity hazardous emission sources (e.g., hazardous water facilities, wastewater discharge indicator) and other environmental and social indicators harnessed from various sources across HOLC graded neighborhoods and extrapolated census tracts (A [lowest risk neighborhoods] to D [highest risk neighborhoods]). Lower graded areas (C and D) had consistently higher exposures to worse environmental factors. Additionally, there were consistent relative disparities in the exposures to PM2.5 (1981-2018) and NO2 (2005-2019), without significant improvement in the gap compared with HOLC grade A neighborhoods. Our findings illustrate that historical redlining, a form of residential segregation largely based on racial discrimination is associated with environmental injustice over the past 2-4 decades.

9.
Can J Cardiol ; 39(9): 1191-1203, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37290538

RESUMEN

The study of the interplay between social factors, environmental hazards, and health has garnered much attention in recent years. The term "exposome" was coined to describe the total impact of environmental exposures on an individual's health and well-being, serving as a complementary concept to the genome. Studies have shown a strong correlation between the exposome and cardiovascular health, with various components of the exposome having been implicated in the development and progression of cardiovascular disease. These components include the natural and built environment, air pollution, diet, physical activity, and psychosocial stress, among others. This review provides an overview of the relationship between the exposome and cardiovascular health, highlighting the epidemiologic and mechanistic evidence of environmental exposures on cardiovascular disease. The interplay between various environmental components is discussed, and potential avenues for mitigation are identified.


Asunto(s)
Enfermedades Cardiovasculares , Humanos , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Exposición a Riesgos Ambientales/efectos adversos , Ejercicio Físico
10.
Bioengineering (Basel) ; 10(3)2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36978751

RESUMEN

Pericoronary adipose tissue (PCAT) features on Computed Tomography (CT) have been shown to reflect local inflammation and increased cardiovascular risk. Our goal was to determine whether PCAT radiomics extracted from coronary CT angiography (CCTA) images are associated with intravascular optical coherence tomography (IVOCT)-identified vulnerable-plaque characteristics (e.g., microchannels (MC) and thin-cap fibroatheroma (TCFA)). The CCTA and IVOCT images of 30 lesions from 25 patients were registered. The vessels with vulnerable plaques were identified from the registered IVOCT images. The PCAT-radiomics features were extracted from the CCTA images for the lesion region of interest (PCAT-LOI) and the entire vessel (PCAT-Vessel). We extracted 1356 radiomic features, including intensity (first-order), shape, and texture features. The features were reduced using standard approaches (e.g., high feature correlation). Using stratified three-fold cross-validation with 1000 repeats, we determined the ability of PCAT-radiomics features from CCTA to predict IVOCT vulnerable-plaque characteristics. In the identification of TCFA lesions, the PCAT-LOI and PCAT-Vessel radiomics models performed comparably (Area Under the Curve (AUC) ± standard deviation 0.78 ± 0.13, 0.77 ± 0.14). For the identification of MC lesions, the PCAT-Vessel radiomics model (0.89 ± 0.09) was moderately better associated than the PCAT-LOI model (0.83 ± 0.12). In addition, both the PCAT-LOI and the PCAT-Vessel radiomics model identified coronary vessels thought to be highly vulnerable to a similar standard (i.e., both TCFA and MC; 0.88 ± 0.10, 0.91 ± 0.09). The most favorable radiomic features tended to be those describing the texture and size of the PCAT. The application of PCAT radiomics can identify coronary vessels with TCFA or MC, consistent with IVOCT. Furthermore, the use of CCTA radiomics may improve risk stratification by noninvasively detecting vulnerable-plaque characteristics that are only visible with IVOCT.

11.
medRxiv ; 2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36711678

RESUMEN

Pericoronary adipose tissue (PCAT) features on CT have been shown to reflect local inflammation, and signals increased cardiovascular risk. Our goal was to determine if PCAT radiomics extracted from coronary CT angiography (CCTA) images are associated with intravascular optical coherence tomography (IVOCT)-identified vulnerable plaque characteristics (e.g., microchannels [MC] and thin-cap fibroatheroma [TCFA]). CCTA and IVOCT images of 30 lesions from 25 patients were registered. Vessels with vulnerable plaques were identified from the registered IVOCT images. PCAT radiomics features were extracted from CCTA images for the lesion region of interest (PCAT-LOI) and the entire vessel (PCAT-Vessel). We extracted 1356 radiomics features, including intensity (first-order), shape, and texture features. Features were reduced using standard approaches (e.g., high feature correlation). Using stratified three-fold cross-validation with 1000 repeats, we determined the ability of PCAT radiomics features from CCTA to predict IVOCT vulnerable plaque characteristics. In identification of TCFA lesions, PCAT-LOI and PCAT-Vessel radiomics models performed comparably (AUC±standard deviation 0.78±0.13, 0.77±0.14). For identification of MC lesions, PCAT-Vessel radiomics model (0.89±0.09) was moderately better associated than that of PCAT-LOI model (0.83±0.12). Both PCAT-LOI and PCAT-Vessel radiomics models also similarly identified coronary vessels thought to be highly vulnerable (i.e., both TCFA and MC) (0.88±0.10, 0.91±0.09). Favorable radiomics features tended to be those describing texture and size of PCAT. PCAT radiomics can identify coronary vessels with TCFA or MC, consistent with IVOCT. CCTA radiomics may improve risk stratification by noninvasively detecting vulnerable plaque characteristics that are only visible with IVOCT.

13.
Environ Sci Pollut Res Int ; 30(8): 20590-20600, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36253577

RESUMEN

The present study aimed to assess the efficiency of the water hyacinth (Eichhornia crassipes (Mart.) Solms) plant for the reduction of nitrogen and phosphorus pollutants from glass industry effluent (GIE) as batch mode phytoremediation experiments. For this, response surface methodology (RSM) and artificial neural networks (ANN) methods were adopted to evidence the optimization and prediction performances of E. crassipes for total Kjeldahl's nitrogen (TKN) and total phosphorus (TP) removal. The control parameters, i.e., GIE concentration (0, 50, and 100%) and plant density (1, 3, and 5 numbers) were used to optimize the best reduction conditions of TKN and TP. A quadratic model of RSM and feed-forward backpropagation algorithm-based logistic model (input layer: 2 neurons, hidden layer: 10 neurons, and output layer: 1 neuron) of ANN showed good fitness results for experimental optimization. Optimization results showed that maximum reduction of TKN (93.86%) and TP (87.43%) was achieved by using 60% of GIE concentration and nearly five plants. However, coefficient of determination (R2) values showed that ANN models (TKN: 0.9980; TP: 0.9899) were superior in terms of prediction performance as compared to RSM (TKN: 0.9888; TP: 0.9868). Therefore, the findings of this study concluded that E. crassipes can be effectively used to remediate nitrogen and phosphorus loads of GIE and minimize environmental hazards caused by its unsafe disposal.


Asunto(s)
Eichhornia , Contaminantes Ambientales , Contaminantes Químicos del Agua , Biodegradación Ambiental , Fósforo , Nitrógeno , Contaminantes Químicos del Agua/análisis , Plantas , Redes Neurales de la Computación
14.
Curr Probl Cardiol ; 48(3): 101533, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36481391

RESUMEN

Neighborhood walkability may be associated with increased physical activity and thus may confer protection against cardiovascular disease and associated risk factors. We sought to characterize the association between neighborhood-level cardiovascular diseases and risk factors with neighborhood walkability across US census tracts.We linked the Centers for Disease Control and Prevention (CDC) PLACES dataset which provided census-tract level prevalence of coronary artery disease (CAD) and cardiovascular risk factors (hypertension, high cholesterol, obesity, and diabetes), with census tract population-weighted national walkability index (NWI) from the US Environmental Protection Agency (EPA). We calculated the mean prevalence of each cardiovascular health indicator per quartile of the walkability score. We also fit a multivariable linear regression model to estimate the association between walkability index and the prevalence of CAD adjusting for age, sex, race, and the CDC'S social vulnerability index, an integrated metric of socioeconomic position. We additionally performed mediation analyses to understand the mediating effects of CAD risk factors on the relationship between NWI and CAD prevalence. A total of 70,123 census tracts were analyzed nationwide. Across walkability quartiles Q1 (least walkable) through Q4 (most walkable), we found statistically significant decrease in the prevalence of CAD (7.0% to 5.4%), and risk factors including hypertension (35.5% to 29.7%), high cholesterol (34.5% to 29.2%), obesity (35.0% to 30.2%), and diabetes (11.6% to 10.6%). After multivariable adjustment, continuous walkability index was negatively and significantly associated with the prevalence of CAD (ß = -0.09, P<0.0001). The relationship between NWI and CAD is partially mediated by the risk factors. High cholesterol accounted for 45%, high blood pressure 41% and diabetes 10% of the total effect of walkability on CAD. While direct relationship between walkability and CAD accounted for 9% of the total effect. This nationwide analysis demonstrates that neighborhood walkability is associated with a lower prevalence of cardiovascular risk factors and CAD. The association between NWI and CAD seems to be partly mediated by prevalence of traditional risk factors.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Diabetes Mellitus , Hipertensión , Humanos , Estados Unidos/epidemiología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Caminata , Factores de Riesgo , Diabetes Mellitus/epidemiología , Obesidad/epidemiología , Obesidad/prevención & control , Factores de Riesgo de Enfermedad Cardiaca , Hipertensión/epidemiología , Colesterol
15.
ACS Omega ; 7(23): 19454-19464, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35721986

RESUMEN

Linen has been a significant material for textile packaging. Thus, the application of the simple spray-coating method to coat linen fibers with a flame-retardant, antimicrobial, hydrophobic, and anticounterfeiting luminescent nanocomposite is an innovative technique. In this new approach, the ecologically benign room-temperature vulcanizing (RTV) silicone rubber was employed to immobilize the environmentally friendly Exolit AP 422 (Ex) and lanthanide-doped strontium aluminum oxide (RESAO) nanoscale particles onto the linen fibrous surface. Both morphological properties and elemental compositions of RESAO and treated fabrics were examined by transmission electron microscopy (TEM), scanning electron microscopy (SEM), wavelength-dispersive X-ray fluorescence (WD-XRF), Fourier transform infrared (FTIR) spectroscopy, and energy-dispersive X-ray spectroscopy (EDX). In the fire resistance test, the treated linen fabrics produced a char layer, giving them the property of self-extinguishing. Furthermore, the coated linen samples' fire-retardant efficacy remained intact after 35 washing cycles. As the concentration of RESAO increased, so did the treated linen superhydrophobicity. Upon excitation at 366 nm, an emission band of 519 nm was generated from a colorless luminescent film deposited onto the linen surface. The coated linen displayed a luminescent activity by changing color from off-white beneath daylight to green beneath UV source, which was proved by CIE Lab parameters and photoluminescence spectral analysis. The photoluminescence effect was identified in the treated linen as reported by emission, excitation, and decay time spectral analysis. The comfort properties of coated linen fabrics were measured to assess their mechanical and comfort features. The treated linen exhibited excellent UV shielding and improved antimicrobial performance. The current simple strategy could be useful for large-scale production of multifunctional smart textiles such as packaging textiles.

16.
J Synchrotron Radiat ; 29(Pt 3): 765-774, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35511009

RESUMEN

Synchrotron radiation-based techniques [X-ray absorption near-edge structure (XANES) and X-ray fluorescence (XRF)] combined with inductively coupled plasma-mass spectrometry (ICP-MS) were used for the assessment of heavy metals concentrations as well as lead (Pb) and nickel (Ni) speciation in airborne particulate matter (PM10) over two residential sites in Greater Cairo. Nineteen 24 h high-volume samples collected at Giza (G) Square and Helwan (H) University (Egypt) were selected for this study. Mean concentrations of heavy metals in PM10 at both sites were found to have the same descending order of Pb > Cu > Ni > Cd > Co > As, of which concentrations of Pb, Cu, Ni and Cd in H samples were higher than those in G samples. For Pb, synchrotron-based XRF results were in good agreement with concentrations obtained by ICP-MS. The XANES spectra of PM10 at the Pb L2-edge and Ni K-edge were compared with those of Pb and Ni in model standard compounds to provide information on the potential oxidation states as well as the chemical forms of those elements. The data show that Pb has similar chemical environments in both series G and H with the predominance of Pb2+ oxidation state. Nickel was found as Ni(OH)2, NiO and Ni metal in the analyzed samples. However, the content of Ni in the background filter shows a very strong interference with that of the collected PM10. Carcinogenic and non-carcinogenic risks resulting from the inhalation of the studied heavy metals were assessed for children and adult residents and were found below the safe limits, at both sites.


Asunto(s)
Metales Pesados , Material Particulado , Adulto , Cadmio/análisis , Niño , Monitoreo del Ambiente , Humanos , Plomo/análisis , Metales Pesados/análisis , Níquel/análisis , Material Particulado/análisis , Medición de Riesgo , Sincrotrones
17.
J Environ Radioact ; 235-236: 106648, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34004546

RESUMEN

The transfer of 137Cs and 85Sr from fallout to plants was studied in two successive pot experiments. Five plant species (Oryza Sativa, Tritichum Vulgares, Vicia Faba, Sesamum Orientale and Trifolium Alexandrinum) were grown in pots containing sandy clay loam soil. For simulating foliar contamination, radioactive 137Cs and 85Sr solutions were sprayed once with different activity concentrations gently on the shooting system. After 8 weeks of radioactivity application to the above first four plants and 4 weeks to the last one, the total absorption of 137Cs and 85Sr and their distribution in different parts of the tested plants were determined. Most of the absorbed 137Cs and 85Sr accumulated in shoots with proportions ranged from 70.8 to 81.9% and from 88.9 to 95.0%, respectively for different plants. The absorbed 137Cs and 85Sr by grains/seeds followed that of shoots with values ranged from 11.9 to 19.2% and from 5 to 10.9%, respectively. The percentage of 137Cs absorbed by roots ranged from 6.2 to 10.0% among different plants, while 85Sr in roots of plants was below the minimum detectable activity of the detector. For Trifolium, most of the absorbed 137Cs and 85Sr accumulated in the first harvest (81.9 and 98.6%). The aggregated transfer factors (Tag) of both radionuclides under foliar conditions were to a great extent similar. The average values of Tag factors (m2kg-1) of 137Cs and 85Sr, respectively, in rice grains were 3.4 × 10-4 and 1.6 × 10-4; in wheat grains were 4.2 × 10-4 and 2.1 × 10-4; in bean seeds were 4.9 × 10-4 and 2.6 × 10-4; and in sesame seeds were 2.8 × 10-4 and 1.2 × 10-4. Those Tag factors of grains/seeds were substantially lower than those obtained with straw of the corresponding plant species.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Radioisótopos de Cesio/análisis , Egipto , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos de Estroncio/análisis
18.
J Environ Radioact ; 234: 106632, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33962220

RESUMEN

The transfer of 137Cs and 85Sr from soil to different plants has been studied in two successive pot field-grown experiments. Five plant species (Oryza Sativa, Tritichum Vulgares, Vicia Faba, Sesamum Orientale and Trifolium Alexandrinum) were grown in pots with sandy clay loam soil contaminated with varying amounts of 137Cs or 85Sr. The absorption of the radioisotopes was measured in different parts of the plants and their activity concentration was significantly increased with increasing radioactivity of both radioisotopes in the soil. The distribution pattern of the total absorbed 137Cs or 85Sr in different plants after soil contamination shows that the shoots of these plants contained the highest percentage of both radionuclides (65.8-73.8% for 137Cs and 77.3-80.7% for 85Sr) followed by roots (16.4-22.4% for 137Cs and 19.5-21.4% for 85Sr) and finally by grains/seeds (4.9-12.9% for 137Cs and 0.3-1.3% for 85Sr). The transfer factors of 85Sr were higher than those of 137Cs for shoots of the tested plants, and were in the ranges of 2.3×10-2 - 4.8×10-2 and 8.8×10-2 - 2.0×10-1 for 137Cs and 85Sr, respectively. The transfer factors of grains or seeds were significantly lower than those of roots or shoots. Also, the transfer factors of leguminous plants were higher than those of cereal plants. Regarding Trifolium plant, the highest activity concentration of both isotopes was found in the second harvest samples.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Radioisótopos de Cesio/análisis , Egipto , Suelo , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos de Estroncio
19.
J Opt Soc Am A Opt Image Sci Vis ; 37(11): C73-C79, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33175734

RESUMEN

This contribution reports on the optical properties of biosynthesised Eu2O3 nanoparticles bioengineered for the first time by a green and cost effective method using aqueous fruit extracts of Hyphaene thebaica as an effective chelating and capping agent. The morphological, structural, and optical properties of the samples annealed at 500°C were confirmed by using a high-resolution transmission electron microscope (HR-TEM), x-ray diffraction analysis (XRD), UV-Vis spectrocopy, and photoluminescence spectrometer. The XRD results confirmed the characteristic body-centered cubic (bcc) structure of Eu2O3 nanoparticles with an average size of 20 nm. HR-TEM revealed square type morphology with an average size of ∼6nm. Electron dispersion energy dispersive x-ray spectroscopy spectrum confirmed the elemental single phase nature of pure Eu2O3. Furthuremore, the Fourier transformed infrared spectroscopy revealed the intrinsic characteristic peaks of Eu-O bond stretching vibrations. UV-Vis reflectance proved that Eu2O3 absorbs in a wide range of the solar spectrum from the VUV-UV region with a bandgap of 5.1 eV. The luminescence properties of such cubic structures were characterized by an intense red emission centered at 614 nm. It was observed that the biosynthesized Eu2O3 nanoparticles exhibit an efficient red-luminescence and hence a potential material as red phosphor.


Asunto(s)
Luminiscencia , Nanopartículas/química , Fenómenos Ópticos , Arecaceae/química , Color , Tamaño de la Partícula , Extractos Vegetales/química
20.
Radiat Prot Dosimetry ; 190(3): 331-341, 2020 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-32852037

RESUMEN

The aim of this work was to use RESRAD-Build model to predict the resulting external and internal radiological doses received by the workers of manganese mine located in Southern Sinai. In order to achieve that goal, measurement of the activity concentrations of natural radionuclides in rock samples collected from the inside gallery of such mine, using hyper pure germanium (HPGe) detector. Radon gas concentrations were also measured. The average activity concentrations of 238U, 226Ra, 232Th, 40K and 210Pb in rock samples were 207.3, 155.5, 59.7, 304.5 and 119.3 Bq kg-1, respectively. The average radon activity concentration was 1254.6 Bqm-3, which is equivalent to 0.135 WL. The radon concentration increases further as going deep inside the mine up to 6238 Bqm-3. RESRAD-Build model occupational effective dose equivalent (EDE) received by the workers, from natural radionuclides, dominated by 222Rn emanated from the parent nuclide 226Ra.There was good agreement between the occupational annual EDE calculated from the measured rock samples and that predicted by modeling, with estimated values of 83.8 and 82.1 mSvy-1, respectively. This radiological dose assessment indicated the predominance of internal pathways owing to radon decay products, in both cases (measured and modeled). The occupational radiological dose from the inhalation of radon and radon decay products resulted in a high lung cancer risk based on the current measurements and ventilation conditions within the mine.


Asunto(s)
Radiactividad , Radio (Elemento) , Radón , Uranio , Humanos , Radioisótopos de Plomo , Manganeso , Radón/análisis , Torio/análisis , Uranio/análisis
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