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1.
Int Urogynecol J ; 35(5): 955-965, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38523161

RESUMEN

INTRODUCTION AND HYPOTHESIS: The objective was to evaluate the prevalence of levator ani avulsion (LAA) among primiparous women with obstetric anal sphincter injury (OASI) and how this association could affect future pelvic floor dysfunction. METHODS: Three electronic databases (MEDLINE/PubMed/EMBASE) were searched in December 2018 and again in October 2022. Nine full-text articles were included in the analysis. The exclusion criteria were language other than English, studies not based on primiparous women only, conference abstracts, and evaluation without ultrasound or MRI. RESULTS: The overall prevalence of LAA was 24% (95% CI: 18-30%). Those with OASI, were at a higher risk of LAA, OR 3.49 (95% CI: 1.46 to 8.35). In women with LAA + OASI versus OASI alone, Three of Five studies showed worsened AI symptoms. Three of Five studies assessing urinary incontinence (UI) reported no significant difference in UI, whereas two reported increased UI. All studies that looked at pelvic organ prolapse reported a higher incidence of symptomatic prolapse and reduced pelvic floor muscle strength in women with LAA + OASI compared with those without LAA. CONCLUSION: Levator ani avulsion is prevalent following vaginal birth and is strongly associated with OASI. Incidence of AI does not increase in women with LAA and OASI, but they had greater symptom bother. OASI with LAA appears to increase the incidence of pelvic floor weakness and pelvic organ prolapse. There is no consensus agreement on the effect of LAA + OASI on UI.


Asunto(s)
Canal Anal , Trastornos del Suelo Pélvico , Humanos , Femenino , Canal Anal/lesiones , Prevalencia , Embarazo , Trastornos del Suelo Pélvico/etiología , Trastornos del Suelo Pélvico/epidemiología , Diafragma Pélvico/lesiones , Diafragma Pélvico/diagnóstico por imagen , Diafragma Pélvico/fisiopatología , Parto Obstétrico/efectos adversos , Incontinencia Fecal/etiología , Incontinencia Fecal/epidemiología , Complicaciones del Trabajo de Parto/epidemiología , Complicaciones del Trabajo de Parto/etiología , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/etiología
2.
Physiol Plant ; 175(6): e14089, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38148212

RESUMEN

Drought is a major abiotic stress that impairs the physiology and development of plants, ultimately leading to crop yield losses. Drought tolerance is a complex quantitative trait influenced by multiple genes and metabolic pathways. However, molecular intricacies and subsequent morphological and physiological changes in response to drought stress remain elusive. Herein, we combined morpho-physiological and comparative RNA-sequencing analyses to identify core drought-induced marker genes and regulatory networks in the barley cultivar 'Giza134'. Based on field trials, drought-induced declines occurred in crop growth rate, relative water content, leaf area duration, flag leaf area, concentration of chlorophyll (Chl) a, b and a + b, net photosynthesis, and yield components. In contrast, the Chl a/b ratio, stoma resistance, and proline concentration increased significantly. RNA-sequence analysis identified a total of 2462 differentially expressed genes (DEGs), of which 1555 were up-regulated and 907 were down-regulated in response to water-deficit stress (WD). Comparative transcriptomics analysis highlighted three unique metabolic pathways (carbohydrate metabolism, iron ion binding, and oxidoreductase activity) as containing genes differentially expressed that could mitigate water stress. Our results identified several drought-induced marker genes belonging to diverse physiochemical functions like chlorophyll concentration, photosynthesis, light harvesting, gibberellin biosynthetic, iron homeostasis as well as Cis-regulatory elements. These candidate genes can be utilized to identify gene-associated markers to develop drought-resilient barley cultivars over a short period of time. Our results provide new insights into the understanding of water stress response mechanisms in barley.


Asunto(s)
Hordeum , Hordeum/genética , Sequías , Deshidratación , Perfilación de la Expresión Génica/métodos , Clorofila , Hierro , ARN , Estrés Fisiológico/genética
3.
Molecules ; 28(12)2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37375199

RESUMEN

Nanoscale ZnO is a vital semiconductor material whose versatility can be enhanced by sensitizing it with metals, especially noble metals, such as gold (Au). ZnO quantum dots were prepared via a simple co-precipitation technique using 2-methoxy ethanol as the solvent and KOH as the pH regulator for hydrolysis. The synthesized ZnO quantum dots were deposited onto glass slides using a simple doctor blade technique. Subsequently, the films were decorated with gold nanoparticles of different sizes using a drop-casting method. The resultant films were characterized via various strategies to obtain structural, optical, morphological, and particle size information. The X-ray diffraction (XRD) reveals the formation of the hexagonal crystal structure of ZnO. Upon Au nanoparticles loading, peaks due to gold are also observed. The optical properties study shows a slight change in the band gap due to Au loading. Nanoscale sizes of particles have been confirmed through electron microscope studies. P.L. studies display blue and blue-green band emissions. The significant degradation efficiency of 90.2% methylene blue (M.B.) was attained in natural pH in 120 min using pure ZnO catalyst while one drop gold-loaded catalysts, ZnO: Au 5 nm, ZnO: Au 7 nm, ZnO: Au 10 nm and ZnO: Au 15 nm, delivered M.B. degradation efficiency of 74.5% (in 245 min), 63.8% (240 min), 49.6% (240 min) and 34.0% (170 min) in natural pH, respectively. Such films can be helpful in conventional catalysis, photocatalysis, gas sensing, biosensing, and photoactive applications.

4.
Eur Arch Otorhinolaryngol ; 279(5): 2465-2471, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34453573

RESUMEN

OBJECTIVE: Resection of middle turbinate in the setting of endoscopic sinus surgery is a controversial procedure. Our aim is to assess the impact of the anterior part middle turbinoplasty on the outcome of endoscopic sinus surgery, incidence of synechia between the middle turbinate and the lateral nasal wall, intra- and post-operative accessibility to the paranasal sinuses. METHODS: Single blinded randomized controlled study of 120 patients with chronic rhinosinusitis without polyps, they were allocated into two groups, we performed anterior part middle turbinoplasty in the group one "60 patients", and we preserved the middle turbinate in the group two "60 patients". We assessed the patients pre-operatively by Sino-nasal outcome Test (SNOT-22), intra-operatively by Likert scale score for the sinuses accessibility. At least 6 months post-operatively, we assessed the patients by SNOT-22, and Likert scale score for sinus accessibility. RESULTS: During and after surgery, the Likert scale score in the group one showed statistically significant better sinuses accessibility than in the group two. We noticed synechia between the MT and the lateral nasal wall in 9.2% and 18.2% of the operated sides in group one and group two, respectively. SNOT-22 and its smell item improved significantly in both groups with no statistically significant differences between them. No major complications were reported. CONCLUSION: Anterior part middle turbinoplasty is a safe and effective technique during endoscopic sinus surgery to improve the intra- and post-operative sinus accessibility, and decrease the incidence of post-operative synechia, with no adverse effect on olfaction or bleeding.


Asunto(s)
Pólipos Nasales , Senos Paranasales , Rinitis , Sinusitis , Enfermedad Crónica , Endoscopía/métodos , Humanos , Pólipos Nasales/cirugía , Senos Paranasales/cirugía , Rinitis/etiología , Rinitis/cirugía , Prueba de Resultado Sino-Nasal , Sinusitis/etiología , Sinusitis/cirugía , Adherencias Tisulares/etiología , Resultado del Tratamiento , Cornetes Nasales/cirugía
5.
Luminescence ; 36(1): 210-214, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32816350

RESUMEN

Characterization of thermoluminescence (TL) properties of lithium borate glass samples doped with different concentrations of dysprosium (Dy) was carried out. Samples were prepared using a melting method at 1100°C and irradiated with ß-particles. The glass samples doped with 0.1% Dy displayed the best TL dosimetric properties compared with other compositions. Deconvoluted analyses of the glow curves displayed five overlapping TL glow peaks located between 392.0 and 510.3 K. A good linear TL dose-response for ß-particles was obtained in the dose range 66.6 mGy to 33.3 Gy. The minimum detectible dose was evaluated to be 205.4 µGy and samples revealed thermal fading in 312 h to 29% of their original value.


Asunto(s)
Boratos , Disprosio , Vidrio , Compuestos de Litio , Dosimetría Termoluminiscente
6.
Eur Arch Otorhinolaryngol ; 278(11): 4477-4481, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33638087

RESUMEN

PURPOSE: Large and combined laryngoceles usually need an external approach. One difficulty in such approach was the dissection at the paraglottic space. To overcome such difficulty, a thyroid chondroplastic flap approach to the paraglottic space was designed. METHODS: This study is a case series of thirty consecutive patients (24 men and six women with an average age of 45.6 years), having large combined laryngocele resected externally between January 1995 and December 2019) at the department of ORL_HNS Tanta University, Egypt. RESULTS: This approach allowed for excellent exposure of the paraglottic space, facilitating complete resection. Complications included perichondrial tearing in five patients, obstructing hematoma in two patient and minimal edema in four patients. CONCLUSIONS: Thyroid chondroplastic flap is an excellent and safe approach for the paraglottic space facilitating complete resection of large laryngoceles.


Asunto(s)
Laringocele , Laringe , Disección , Egipto , Femenino , Humanos , Laringe/cirugía , Masculino , Persona de Mediana Edad , Colgajos Quirúrgicos , Glándula Tiroides
7.
Molecules ; 26(16)2021 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-34443295

RESUMEN

In Saudi Arabia, more than 335,000 tons of cow manure is produced every year from dairy farming. However, the produced cow manure is usually added to the agricultural soils as raw or composted manure; significant nitrogen losses occur during the storage, handling, and application of the raw manure. The recovery of ammonia from cow manure through thermochemical treatments is a promising technique to obtain concentrated nitrogen fertilizer and reducing nitrogen losses from raw manure. However, the byproduct effluents from the recovery process are characterized by different chemical properties from the original raw manure; thus, its impact as soil amendments on the soil carbon and nitrogen dynamics is unknown. Therefore, a 90-day incubation experiment was conducted to study the impact of these effluents on CO2 efflux, organic C, microbial biomass C, available NH4+, and NO3- when added to agricultural soil. In addition to the two types of effluents (produced at pH 9 and pH 12), raw cow manure (CM), composted cow manure (CMC), cow manure biochar (CMB), and control were used for comparison. The application of CM resulted in a considerable increase in soil available nitrogen and CO2 efflux, compared to other treatments. Cow manure biochar showed the lowest CO2 efflux. Cumulative CO2 effluxes of cow manure effluents were lower than CM; this is possibly due to the relatively high C:N ratio of manure effluent. The content of P, Fe, Cu, Zn, and Mn decreased as incubation time increased. Soil microbial biomass C for soil treated with cow manure effluents (pH 12 and 7) was significantly higher than the rest of the soil amendments and control.

8.
Bull Environ Contam Toxicol ; 107(5): 889-894, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34370087

RESUMEN

Chemical pollution poses adverse effects on aquatic organisms, including altered gene expression. This study, therefore, investigated the hepatic expression of biomarkers of exposure and effect in Oreochromis niloticus inhabiting the drainage canal of a sugarbeet factory (an industrially polluted habitat) and the Nile River (a reference habitat). Compared to the Nile River, the drainage canal contained significantly elevated levels of heavy metals (Cd, Fe, Mn, Co, and Pb), nitrate, ammonia, nitrite, chemical oxygen demand, and biological oxygen demand. The liver of O. niloticus from the drainage canal accumulated significantly higher concentrations of the heavy metals. O. niloticus from the drainage canal had significantly higher hepatic expressions of genes related to oxidative stress (GSTa, GPx, and NRF2), metal toxicity (MT), endocrine disruption (Vtg), and hypoxia (HIF1a) and a significantly lower hepatic expression of the apoptosis-associated CAS gene. CYP1A (a detoxification biomarker) expression did not exhibit significant differences. These results provide insights into complex adaptive responses of O. niloticus to multiple chemicals and support the utilization of molecular biomarkers as warning signals for water pollution.


Asunto(s)
Cíclidos , Metales Pesados , Contaminantes Químicos del Agua , Animales , Biomarcadores , Cíclidos/genética , Egipto , Metales Pesados/análisis , Metales Pesados/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
9.
Heart Surg Forum ; 23(3): E270-E275, 2020 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-32524985

RESUMEN

BACKGROUND: This is a prospective randomized-controlled study done to evaluate the best surgical option for moderate ischemic mitral regurgitation through either coronary artery bypass grafting only or by performing additional mitral repair. METHODS: Over a nine-month period, 60 patients with ischemic heart disease associated with moderate ischemic mitral regurgitation were equally divided into two groups. Group 1 included 30 patients who had coronary artery bypass grafting with mitral valve repair; Group 2 included 30 patients who had only coronary artery bypass grafting. RESULTS: There were no significant differences between the study groups, regarding operative data, apart from the cardiopulmonary bypass time and aortic cross-clamp time, which were significantly longer in group 1 (P < 0.001). Only one patient died in group 1 due to severe myocardial dysfunction. During the follow up, the NYHA class improved in group 1, from 2.7 to 1.35 (P < 0.004), compared with group 2, where the NYHA class improved from 2.6 to 1.72 (P = 0.07). The degree of MR improved in 28 patients (93%) in group 1 and 22 patients (73%) in group 2 (P < 0.0001). CONCLUSION: The study revealed many advantages of adding mitral repair to surgical revascularization in patients with moderate ischemic mitral regurgitation, with improvement in the degree of MR and NYHA functional class. On the other hand there were no significant differences between the groups, regarding the postoperative course and incidence of mortality.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas/métodos , Insuficiencia de la Válvula Mitral/cirugía , Válvula Mitral/cirugía , Isquemia Miocárdica/cirugía , Revascularización Miocárdica/métodos , Angiografía Coronaria , Ecocardiografía Transesofágica , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/diagnóstico , Insuficiencia de la Válvula Mitral/etiología , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/fisiopatología , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Función Ventricular Izquierda/fisiología
10.
J Environ Manage ; 241: 458-467, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31027831

RESUMEN

Biochar application has multiple benefits for soil fertility improvement and climate change mitigation. Biochar can act as a source of nutrients and sequester carbon (C) in the soil. The nutrient release capacity of biochar once applied to the soil varies with the composition of the biochar, which is a function of the feedstock type and pyrolysis condition used for biochar production. Biochar has a crucial influence on soil C mineralization, including its positive or negative priming of microorganisms involved in soil C cycling. However, in various cases, biochar application to the soil may cause negative effects in the soil and the wider environment. For instance, biochar may suppress soil nutrient availability and crop productivity due to the reduction in plant nutrient uptake or reduction in soil C mineralization. Biochar application may also negatively affect environmental quality and human health because of harmful compounds such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzodioxins, and dibenzofurans (PCDD/DF). In this review, we discuss the linkage between biochar composition and function, evaluate the role biochar plays in soil fertility improvement and C sequestration, and discuss regulations and concerns regarding biochar's negative environmental impact. We also summarize advancements in biochar production technologies and discuss future challenges and priorities in biochar research.


Asunto(s)
Carbono , Suelo , Carbón Orgánico , Humanos , Nutrientes
11.
Environ Monit Assess ; 189(6): 252, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28474201

RESUMEN

The present study was conducted in one of the most densely cultivated area of Al-Qassim region in Kingdom of Saudi Arabia to (i) monitor trace metal (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) contents in surface and subsurface soils, (ii) assess the pollution and potential ecological risk levels of trace metals, and (iii) identify trace metal sources using enrichment factor (EF), correlation matrix, and principal component analysis (PCA). The pollution levels of the analyzed trace metals calculated by the geoaccumulation index (I geo) and contamination factor (C f) suggested that the soils were highly contaminated with Cd and moderately contaminated with Pb. Based on the average values of EF, soil samples were found to present extremely high enrichment for Cd, significant enrichment for Pb, moderate enrichment for Zn, and deficient to minimal enrichment for other trace metals. Among the analyzed trace metals, a very high ecological risk was observed only in the case of Cd at some sampling sites. Meanwhile, other investigated trace metals had a low ecological risk. The results of PCA combined with correlation matrix suggested that Fe, Mn, Zn, Cu, Cr Ni, Cu, and Co represent natural abundance in soil, but Cd, Pb, and Cu are of anthropogenic inputs, mainly due to agrochemical and fertilizer applications. It could be generally concluded that the obtained results can be useful for assessing and conducting a future program for trace metal monitoring in agricultural areas of Saudi Arabia.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Ecología , Fertilizantes/análisis , Medición de Riesgo , Arabia Saudita , Suelo/química
12.
Environ Geochem Health ; 38(2): 511-21, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26100325

RESUMEN

Biochar has emerged as a universal sorbent for the removal of contaminants from water and soil. However, its efficiency is lower than that of commercially available sorbents. Engineering biochar by chemical modification may improve its sorption efficiency. In this study, conocarpus green waste was chemically modified with magnesium and iron oxides and then subjected to thermal pyrolysis to produce biochar. These chemically modified biochars were tested for NO3 removal efficiency from aqueous solutions in batch sorption isothermal and kinetic experiments. The results revealed that MgO-biochar outperformed other biochars with a maximum NO3 sorption capacity of 45.36 mmol kg(-1) predicted by the Langmuir sorption model. The kinetics data were well described by the Type 1 pseudo-second-order model, indicating chemisorption as the dominating mechanism of NO3 sorption onto biochars. Greater efficiency of MgO-biochar was related to its high specific surface area (391.8 m(2) g(-1)) and formation of strong ionic complexes with NO3. At an initial pH of 2, more than 89 % NO3 removal efficiency was observed for all of the biochars. We conclude that chemical modification can alter the surface chemistry of biochar, thereby leading to enhanced sorption capacity compared with simple biochar.


Asunto(s)
Carbón Orgánico , Óxido Nítrico/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Cinética , Microscopía Electrónica de Rastreo , Termodinámica , Difracción de Rayos X
13.
Bull Environ Contam Toxicol ; 96(5): 622-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27010396

RESUMEN

This study was conducted to identify and quantify polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in soil samples collected from selected industrial areas in the central and eastern regions of Saudi Arabia. All the investigated compounds of PCDDs/PCDFs were identified in the studied locations. The average concentrations of PCDDs (sum of seven congeners measured) ranged from 11.5 to 59.6 pg g(-1), with a maximum concentration of 125.7 pg g(-1) at an oil refinery station followed by 100.9 pg g(-1) at a cement factory. The average concentrations of PCDFs (sum of 10 congeners measured) accounted for 11.68-19.35 pg g(-1), with a maximum concentration of 38.67 pg g(-1) at the cement factory. It was generally observed that the soil samples collected from industrial areas have substantially high toxicity equivalence (TEQ) values of PCDDs/PCDFs compared to soils of remote areas. Principal component analysis revealed that the cement factories and oil refineries were the primary sources of PCDDs and PCDFs.


Asunto(s)
Dibenzofuranos Policlorados/análisis , Dibenzodioxinas Policloradas/análisis , Contaminantes del Suelo/análisis , Suelo/química , Dibenzofuranos Policlorados/química , Monitoreo del Ambiente , Residuos Industriales , Industrias , Dibenzodioxinas Policloradas/química , Análisis de Componente Principal , Arabia Saudita , Contaminantes del Suelo/química
14.
Gastroenterology ; 146(4): 970-9; quiz e15-6, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24389304

RESUMEN

BACKGROUND & AIMS: Primary sclerosing cholangitis (PSC) is a chronic cholestatic disease that leads to extensive liver fibrosis and cirrhosis, which are associated with poor outcome. However, there are no validated noninvasive markers of liver fibrosis in patients with PSC. We assessed the diagnostic performance, reproducibility, longitudinal changes, and prognostic value of liver stiffness measurement (LSM) using vibration-controlled transient elastography (VCTE). METHODS: In a prospective study, we analyzed percutaneous liver biopsy specimens from 73 consecutive patients with PSC from January 2005 to December 2010. Patients underwent VCTE no more than 6 months after the biopsy specimens were collected. The biopsy specimens were analyzed by a pathologist blinded to the results of VCTE for the stage of fibrosis, and LSM was associated with the stage of fibrosis and other variables using the Kruskal-Wallis and Spearman correlation tests. The cutoff values of LSM were selected based on the accuracy with which they identified the stage of fibrosis on receiver-operating characteristic analysis. The rates of LSM progression were assessed using a linear mixed model, and the association between LSM values and clinical outcomes were evaluated using Cox regression analysis in 168 patients with PSC treated with ursodeoxycholic acid and followed up from November 2004 to July 2013 (mean follow-up period, 4 years). RESULTS: LSM was independently linked to the stage of fibrosis. Cutoff values for fibrosis stages ≥F1, ≥F2, ≥F3, and F4 were 7.4 kPa, 8.6 kPa, 9.6 kPa, and 14.4 kPa, respectively. The adjusted diagnostic accuracy values for severe fibrosis and cirrhosis were 0.83 and 0.88, respectively. The diagnostic performance of LSM was comparable to that of hyaluronic acid measurement but superior to the aspartate aminotransferase/platelet ratio index, FIB-4 score, and Mayo risk score in differentiating patients with significant or severe fibrosis from those without. LSM had a high level of reproducibility between operators for the same measurement site and for the same operator between 2 adjacent sites. LSM increased significantly and exponentially over time. Baseline measurements and rate of LSM progression were strongly and independently linked with patients' outcomes. CONCLUSIONS: VCTE is able to differentiate severe from nonsevere liver fibrosis with high levels of confidence in patients with PSC. Baseline measurements of LSM and longitudinal changes are prognostic factors for PSC.


Asunto(s)
Colangitis Esclerosante/complicaciones , Diagnóstico por Imagen de Elasticidad , Cirrosis Hepática/etiología , Hígado/patología , Adolescente , Anciano , Biopsia , Colangitis Esclerosante/diagnóstico , Colangitis Esclerosante/mortalidad , Progresión de la Enfermedad , Elasticidad , Femenino , Humanos , Modelos Lineales , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/mortalidad , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Curva ROC , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Factores de Tiempo , Adulto Joven
15.
J Environ Radioact ; 276: 107415, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703692

RESUMEN

With the thriving fossil fuel and nuclear based industries in the nation, radioecology has become necessary for the radiation safety and emergency-preparedness for the United Arab Emirates (UAE). Environmental radiation transport modelling in the UAE and the Arabian Peninsula are severely limited, as we discuss in this paper, due to lack of experiments specific to arid desert climates. To fill the missing gaps in the baseline arid region radioecological database, especially for the soil-plant uptake studies, rigorous field works have been conducted for the first time on the soil and plant in the farms and open fields of the UAE. We present Abu Dhabi based measurements of activity concentrations of radionuclides of natural origins, in soils, key vegetables (cucumber, tomato, and bell pepper), and leaves of ghaf - a prominent native tree. The empirical data are utilized to get the first published estimates of UAE-specific plant-soil concentration ratios (CR), measuring root uptake of radionuclides in nonleafy vegetables and native trees. Such systematic studies are very rare for arid sandy soils. For the 27 samples analyzed, the activity concentrations' (unit Bq kg-1) ranges are: 169-1746 for 40K, 12-19.5 for 226Ra, and 2.7-23.1 for 228Ra. Likewise, wide variability is seen in the averages of concentration ratios also, ranging in 1.05-4.94 for 40K, 0.14-1.82 for 226Ra, and 0.53-2.78 for 228Ra. A net bioaccumulation (concentration ratio >1) of some of these natural radionuclides is found in many samples, but no significant doses or hazard indices are found due to these three radionuclides in the UAE's soils and vegetations. The paper discusses the careful work through tens of field sampling exercises, well controlled sample processing, high resolution gamma spectrometry, and treatment of data from gamma counting rates to accumulated dose rate estimations.


Asunto(s)
Hojas de la Planta , Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Verduras , Contaminantes Radiactivos del Suelo/análisis , Contaminantes Radiactivos del Suelo/metabolismo , Monitoreo de Radiación/métodos , Verduras/química , Verduras/metabolismo , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Emiratos Árabes Unidos , Suelo/química
16.
Sci Rep ; 14(1): 7614, 2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38556524

RESUMEN

One of the main components of the worldwide transition to sustainable energy is solar cells, usually referred to as photovoltaics. By converting sunlight into power, they lessen their reliance on fossil fuels and the release of greenhouse gases. Because solar cells are decentralized, distributed energy systems may be developed, which increases the efficiency of the cells. Chalcogenide perovskites have drawn interest due to their potential in solar energy conversion since they provide distinctive optoelectronic characteristics and stability. But high temperatures and lengthy reaction periods make it difficult to synthesise and process them. Therefore, we present the inaugural numerical simulation using SCAPS-1D for emerging inorganic BaZrS3/CuO heterojunction solar cells. This study delves into the behaviour of diverse parameters in photovoltaic devices, encompassing efficiency (η) values, short-circuit current density (Jsc), fill factor (FF), and open-circuit voltage (Voc). Additionally, we thoroughly examine the impact of window and absorber layer thickness, carrier concentration, and bandgap on the fundamental characteristics of solar cells. Our findings showcase the attainment of the highest efficiency (η) values, reaching 27.3% for our modelled devices, accompanied by Jsc values of 40.5 mA/cm2, Voc value of 0.79 V, and FF value of 85.2. The efficiency (η) values are chiefly influenced by the combined effects of Voc, Jsc, and FF values. This optimal efficiency was achieved with CuO thickness, band gap, and carrier concentration set at 5 µm, 1.05 eV, and above 1019 cm-3, respectively. In comparison, the optimal parameters for BaZrS3 include a thickness of 1 µm, a carrier concentration below 1020 cm-3, and a band gap less than 1.6 eV. Therefore, in the near future, the present simulation will simultaneously provide up an entirely novel field for the less defective perovskite solar cell.

17.
RSC Adv ; 14(9): 6324-6338, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38380235

RESUMEN

In this research study, recovered carbon black (rCB) was obtained via pyrolysis of waste tires. The obtained rCB was then converted into activated carbon species through both chemical treatment and microwave coupled with chemical treatment as a two-step activation process. The activated carbon obtained from chemical activation was denoted as C-AC, while that obtained from exposure to microwave followed by chemical activation was labeled as MC-AC. These two structures were consequently introduced as sorbents for the removal of cadmium ions from an aqueous solution. The structural characteristics of the introduced adsorbents were confirmed using various techniques, namely X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and energy-dispersive X-ray (EDX) spectroscopy. Additionally, textual features of these adsorbents were acquired via both scanning electron microscopy (SEM) and N2 adsorption-desorption BET surface area analyses. These two structures were then introduced for Cd ion adsorption under different operating conditions. Particularly, the effect of pH, contact time, adsorbent dose, and metal ion concentration on the efficiency of adsorption was investigated. The 1maximum adsorption capacity was detected at a pH value of 5.0, a contact time of 30 min, a sorbent dose of 0.4 g L-1, and an initial metal concentration of 50 mg L-1 using MC-AC, which exhibited nearly double the sorption capacity detected for C-AC. Kinetic studies indicated that the process of Cd(ii) adsorption is perfectly described and fitted by the pseudo-second-order model. However, adsorption isotherms for the two adsorbents were found to match the Langmuir model, referring to the occurrence of uniform monolayer adsorption for the metal ions. Thermodynamic analysis demonstrated that the adsorption process was spontaneous and endothermic.

18.
Dalton Trans ; 52(39): 14194-14209, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37755437

RESUMEN

The wastewater released from different industries is a major environmental issue that has grabbed significant attention lately. Thus, the implementation of suitable routes for the treatment of such water is strongly recommended to reach the level of possible reuse for either industrial or agricultural purposes. In line with such a concept, this research work introduces a new composite structure made via the coating of polyacrylamide by loading nickel hydroxide nanoparticles for use as an absorbent for the purification of wastewater from dye contaminants. High internal phase emulation (HIPE) polymerization was utilized to first prepare particles of polyacrylamide followed by their coating with particles of nickel hydroxide to ultimately obtain the designated adsorbent. The structural features and chemical composition of the synthesized composite were confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and energetic dispersive X-ray (EDX) spectroscopy. Additionally, scanning electron microscopy (SEM) and N2 adsorption-desorption surface area analysis were employed to detect the textural characteristics of the composite. Subsequently, the efficiency of this structure, as an adsorbent for the disposal of methylene blue dye species from a wastewater sample, was studied. During the water purification process, several operating parameters, namely, retention time, solution pH, initial concentration, and absorbent dose, were investigated. The presented Ni-polyacrylamide composite achieved the promising removal of methylene blue dye. An increased adsorption capacity of 14.3 mg g-1 toward methylene blue was achieved by the composite, thanks to the presence of both organic and inorganic functional groups within its structure. Kinetic and isotherm studies for the adsorption of methylene blue species were found to fit pseudo-second-order and Langmuir models. Additionally, thermodynamic measurements indicated that the adsorption process of methylene blue is feasible, spontaneous, involves physisorption, and is endothermic.

19.
RSC Adv ; 13(36): 25334-25349, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37622016

RESUMEN

Effluent water from different industries is considered one of the most serious environmental pollutants due to its non-safe disposal. Therefore, proper treatment methods for such wastewater are strongly stimulated for its potential reuse in industries or agriculture. This study introduces a composite fabricated via doping of polystyrene with nanoparticles of cobalt hydroxide as a novel adsorbent for dye and heavy metal decontamination from wastewater. The adsorbent fabrication involves the preparation of polystyrene via high-internal phase emulation (HIPE) polymerization followed by its intercalation with particles of alkali cobalt. The chemical composition and structural properties of the synthesized composite were confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and energy-dispersive X-ray spectroscopy (EDX). Moreover, scanning electron microscopy (SEM) and N2 adsorption-desorption surface area analysis were performed to identify the surface and morphological characteristics of the composite. Then, the ability of this structure toward the removal of methylene blue dye (MB) and heavy metal (iron iii) species from waste aqueous solutions was investigated. Successful elimination for both MB and Fe(iii) was achieved by the presented composite. Elevated adsorption capacities of 75.2 and 112.3 mg g-1, toward MB and Fe(iii) respectively, were detected for the presented polymer-metal hydroxide composite. The increased values of the composite are attributed to the presence of both organic and inorganic functional groups within its structure. Kinetic and isotherm studies for the removal of both cationic species revealed that adsorption processes fit the pseudo-second-order kinetic model and Langmuir isotherm model. Additionally, thermodynamics measurements indicated that the adsorption process of methylene blue and Fe ions is feasible, spontaneous, physisorption, and endothermic.

20.
Sci Rep ; 13(1): 19391, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37938602

RESUMEN

In this study, metal oxides nanoparticles heterogeneous photocatalysts prepared by coprecipitation and ultrasonic techniques were used for diesel desulfurization. They were characterized by scanning electron microscope, powder X-ray diffraction, energy dispersive analysis, diffused reflectance spectra, photoluminescence analysis and BET surface area. The surface area of catalyst B is larger than catalyst A confirming its higher reactivity. X-ray reflectance spectroscopy was used to analyze the sulfur contents in feed. Thiophene was used as a model fuel to evaluate the photocatalytic activity of catalysts A and B. Using the Scherrer equation, sharp and intense signals suggesting their higher degrees of crystallinity, with average crystal sizes for ZnO, Bi2O3, catalysts A and B, respectively; of 18, 14.3, 29.7, and 23.8 nm. The operational parameters of the desulfurization process were optimized and have been studied and the maximum sulfur removal was achieved via a further solvent extraction step. A diesel fuel with a 24 and 19 ppm sulfur content and hence a total sulfur removal of 94.6% and 95.7% was acquired for catalysts A and B, respectively (sulfur compounds concentration in diesel fuel feedstock was 450 ppm). These findings demonstrated that photocatalysts A and B are good and effective catalysts for desulfurization of diesel fuel.

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