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1.
Artículo en Inglés | MEDLINE | ID: mdl-39093718

RESUMEN

Spatially resolved photoluminescence (PL) and electroluminescence (EL) imaging technologies play a crucial role in evaluating the performance and stability of photovoltaic devices. However, their application in perovskite devices presents unique challenges. In this study, we report a discrepancy between the electrical performance of perovskite solar modules (PSMs) and the EL images. Following the application of a reverse bias voltage, we observed an increase in EL brightness associated with prolonged carrier lifetime and transport length. Furthermore, cross-sectional Kelvin probe force microscopy identified a significant potential increase primarily at the electron-transport layer (ETL) side after reverse bias, suggesting the presence of defective ETL/perovskite interfaces with filled hole traps. To address this EL mismatch, we proposed a mild reverse current recovery method aimed at aligning EL images with the cell performance without compromising device efficiency. This approach effectively mitigates discrepancies, ensuring alignment between the device performance and EL imaging. Our study underscores that caution is required when utilizing EL imaging to monitor spatial homogeneity in PSMs for future industrial production.

2.
Int J Biol Macromol ; 277(Pt 1): 133697, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38996882

RESUMEN

In this study, hydrogel beads were fabricated using alginate (Algt) polymer containing dispersed nickel phthalocyanine (NTC) nanomaterial. The viscous solution of Algt and NTC was poured dropwise into a divalent Ca2+ ions, resulting in the formation of hydrogel beads known as NTC@Algt-BDs. The surface of the NTC@Algt-BDs was further modified by coating them with different types of metal ions, yielding metal-coated M+/NTC@Algt-BDs. The adsorbed metal ions i.e., Cu+2, Ag+, Ni+2, Co+2, and Fe+3 were subsequently reduced to zero-valent metal nanoparticles (M0) by NaBH4. The prepared beads were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Initially, M0/NTC@Algt-BDs were examined for the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). Among them, Cu0/NTC@Algt-BDs catalyst exhibited the highest reduction rate and therefore, investigated for reduction of different nitrophenols (NPs) and dyes, including 2-nitrophenol (2-NP), 2,6-dinitrophenol (2,6-DNP), methyl orange (MO), potassium ferrocyanide (PFC), congo red (CR), and acridine orange (ArO). The highest reduction rates of 2.019 and 1.394 min-1 were observed for MO and 2-NP, respectively. Furthermore, the fabricated catalysts were employed for the efficient production of H2 gas by NaBH4 methanolysis. Among which the Ag0/NTC@Algt-BDs catalyst showed excellent catalytic production of H2 gas, exhibiting the lowest activation energy (Ea) of 25.169 kJ/mol at ambient temperature. Furthermore, the impact of NaBH4 amount, and catalyst dosage on the reduction of 2-NP and H2 gas production was conducted whereas the effect of temperature on methanolysis of NaBH4 for evolution of H2 gas was studied. The amount of H2 gas was confirmed by GC-TCD system. Additionally, the recyclability of the catalyst was investigated, as it garnered significant research interest.

3.
Pharm Dev Technol ; : 1-16, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39023747

RESUMEN

Letrozole (LTZ) is used as first-line treatment for hormone-positive breast cancer (BC) in postmenopausal women. However, its poor aqueous solubility and permeability have reduced its clinical efficacy. Herein, we developed LTZ-nanotransferosomes (LTZ-NT) to address above mentioned issues. The LTZ-NT were optimized statistically using Design Expert® followed by their characterization via dynamic light scattering (DLS), Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and Differential scanning calorimetry (DSC). The optimized LTZ-NT was incorporated into 1% chitosan-gel to develop LTZ-NTG. Moreover, in vitro drug release and ex vivo permeation of LTZ-NTG were performed and compared with LTZ-dispersion and LTZ-NT. Additionally, skin irritability and histopathology of LTZ-NTG were investigated. Furthermore, in vitro antitumor study of LTZ-NTG was investigated in BC cell lines. The optimized LTZ-NT showed suitable zeta potential (30.4 mV), spherical size (162.5 nm), and excellent entrapment efficiency (88.04%). Moreover, LTZ-NT exhibited suitable thermal behavior and no interactions among its excipients. In addition, LTZ-NTG had an optimal pH (5.6) and a suitable viscosity. A meaningfully sustained release and improved permeation of LTZ was observed from LTZ-NTG. Additionally, LTZ-NTG showed significantly enhanced cell death of MCF-7 and MCC-7 cells. It can be concluded that LTZ-NTG has the potential to deliver chemotherapeutic agents for possible treatment of BC.

4.
RSC Adv ; 14(30): 22017-22027, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39006770

RESUMEN

Polymeric bio-composites synthesized via a green approach using natural herbs have fascinating anticoagulant activity due to their eco-friendly and non-toxic behavior towards various physical and chemical actions. Herein, we introduce a simple and eco-friendly approach for the fabrication of a new hybrid type of bio-composite based on sulfated carboxymethyl cellulose (S-CMC) and Azadirachta indica leaf powder (S-CMC/NLP). First, a non-toxic sulfating agent called N(SO3Na)3 was used to modify carboxymethyl cellulose into S-CMC. With an ion exchange capacity of 0.25 meq. g-1, the level of sulfation (%) of S-CMC (modified polysaccharide) was measured to be 12.01%. Three types of S-CMC/NLP bio-composites were developed by varying the concentration of NLP. FE-SEM, EDX, and XRD were used to characterize the structural features of S-CMC/NLP bio-composites. FTIR spectroscopy indicated that the S-CMC/NLP bio-composite possesses COO-, -OH and SO3- groups, suggesting the structural similarity to heparin. In addition, the anticoagulant effect of the S-CMC/NLP bio-composite was investigated using PT and APTT assays. The APTT investigation confirmed that following the intrinsic pathway of the coagulation system, 2-NLP/S-CMC bio-composite dose-dependently (0.045-0.28 mg mL-1) prolonged the time of blood coagulation compared to control (pure plasma). The S-CMC/NLP bio-composite showed its potential as a new, safe, and effective candidate for anticoagulant activity.

5.
J Family Med Prim Care ; 13(4): 1223-1231, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38827724

RESUMEN

Introduction: In diabetes mellitus (DM) patients, obtaining a good night's sleep is crucial for maintaining body caloric intake, controlling insulin levels, and reducing the likelihood of engaging in unhealthy behavior. Patients with poor sleep quality may experience impaired glycemia, playing a significant role in the development of chronic complications. This study aims to explore the effects of DM complications on sleep quality among Saudi Arabian patients. Patient and Methods: This is a cross-sectional study conducted among patients with diabetes. A self-administered, validated questionnaire translated into Arabic was distributed among diabetic patients using an online survey. The questionnaire includes sociodemographic characteristics (i.e. age, gender, marital status, etc.), the medical history of the patients, and a questionnaire about sleep quality. Results: Out of 4171 patients involved, 52.7% were females and 27.7% were aged between 40 and 60 years old. The prevalence of patients with perceived poor sleep quality was 24.1%. Significant predictors of poor sleep quality were the gender female, having social stressors, comorbid sleep disorders, associated comorbidities, increasing HbA1c levels, being overweight/obese, and diabetes complications. Furthermore, sleep disturbance, taking sleep medications, daytime sleepiness, and having bad dreams during sleep were also identified as prognostic factors for poor sleep quality. Conclusion: The subjective poor sleep quality of patients with diabetes was 24.1%. Poor sleep quality was significantly demonstrated by females who were having social stressors, comorbid sleep disorders, comorbidities, uncontrolled HbA1c levels, elevated BMI levels, and complications of diabetes. However, regular physical activity and adequate sleep were estimated to be the protective factors against poor sleep quality. Further research is needed to establish the effect of sleep quality among patients with DM.

6.
Des Monomers Polym ; 27(1): 35-50, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38903406

RESUMEN

The C3-symmetry ionic polymer PPyTri has been designed with multi-walled carbon nanotubes (MWCNTs) or graphene nanoplatelets (GNPs) and studied as an ultrasensitive electrochemical sensor for trace Hg(II) detection. The synthesis approach incorporated attaching three pyridinium cationic components with chloride anions to the triazine core. The precursors, BPy, were synthesized using a condensation process involving 4-pyridine carboxaldehyde and focused nicotinic hydrazide. The polymer PPyTri was further modified with either MWCNTs or GNPs. The resulting ionic polymer PPyTri and its fabricated nanocomposites were characterized using infrared (IR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and powder X-ray diffraction (XRD). The analysis revealed that both the polymer and its nanocomposites have semi-crystalline structures. The electroactivity of the designed nanocomposites toward Hg + 2 ions revealed that among the nanocomposites and bare copolymer, the glassy carbon electrode (GCE) adapted with the PPyTri GNPs-5% exhibited the greatest current response over a wide range of Hg + 2 concentrations. The nanocomposite-modified electrode presented an excellent sensitivity of 83.33 µAµM - 1 cm - 2, a low detection limit of 0.033 nM, and a linear dynamic range of 0.1 nM to 0.01 mM (R2 = 0.9945).

7.
Anal Methods ; 16(26): 4333-4346, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38888440

RESUMEN

A poly(luminol-o-anisidine-o-toluidine) terpolymer was synthesized, characterized, and modified with GNPs and ZnO NPs. The nanocomposites were then examined for their electroactivity and potential use as cationic electrochemical sensors for detecting Sb3+ ions in phosphate buffer on the surface of a glassy carbon electrode (GCE). Among the different compositions and the terpolymer, the GCE adapted with the PLAT/ZnO/GNPs-5% nanocomposite displayed the highest current response. The fabricated nanocomposite sensor exhibited high sensitivity, with a value of 21.4177 µA µM-1 cm-2, and a low detection limit of 95.42 pM. The analytical performance of the sensor was evaluated over the linear dynamic range (LDR) of 0.1 nM to 0.01 mM. The proposed sensor is effective in detecting and measuring carcinogenic Sb3+ ions in real environmental samples using an electrochemical approach, making it a promising tool for environmental monitoring.

8.
AME Case Rep ; 8: 29, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38711903

RESUMEN

Background: Candy cane syndrome (CCS) is a rare and underreported complication, seldom occurring after bariatric surgeries, especially, the Roux-en-Y gastric bypass (RYGB) type. It refers to an excessively long-blind end of the alimentary limb, usually at the gastrojejunal (GJ) junction, and to a lesser extent, can occur at the jejunojejunal (JJ) junction, that may cause symptoms including abdominal pain, regurgitation, nausea, vomiting and reflux. However, its diagnosis can be challenging and misleading. Case Description: A 34-year-old woman with a multiple past surgical history presented with small bowel obstruction (SBO) symptoms following a second gastric bypass surgery. An esophagogastroduodenoscopy (EGD) was inconclusive, then a computed tomography (CT) scan was done, which reported intussusception. The patient underwent laparoscopy, which revealed an anastomosis with an extra 14 cm of single-loop bowel near the JJ junction rather than intussusception, leading to a diagnostic laparoscopy followed by a mini-laparotomy procedure. Adhesiolysis followed by a resection of the elongated blind end was done, hence, the diagnosis of CCS was established. The patient tolerated the surgery with a complete resolution of her symptoms; no subsequent complications were reported. Conclusions: The frequency of RYGB surgery and the number of past surgeries a patient might have undergone might correlate independently with the risk of developing CCS.

9.
Cureus ; 16(3): e55864, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38595880

RESUMEN

Meniere's disease is defined by the presence of three essential symptoms: episodic vertigo, tinnitus, and sensorineural hearing loss. The mainstay of its management constitutes lifestyle modification and medical and surgical therapies. Cupping therapy is an ancient treatment that is still widely used especially in the Middle East, Africa, and the United Kingdom. This study portraits the case of a 54-year-old patient suffering from long-standing Meniere's disease. The patient was treated with the routine treatment that was to no avail. It was decided that the patient undergoes cupping therapy. Over two years of monthly cupping therapy sessions, the patient reported a decrease in intensity and frequency of symptoms until its disappearance. Cupping therapy has shown a positive outcome on the patient. According to our search, there is a previous case report published in 2020 that shares multiple similarities with our case. Further studies on cupping therapy and its efficacy, mechanism of action, and complications on a larger scale are advised.

10.
Heliyon ; 10(7): e27303, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38571584

RESUMEN

Five 2-phenylacetohydrazide derivatives (BPAH = N'-benzylidene-2-phenylacetohydrazide, HBPAH = N'-(2-hydroxybenzylidene)-2-phenylacetohydrazide), PPAH = 2-phenyl-N'-3-phenylallylideneacetohydrazide, FMPAH = N'-(furan-2-ylmethylene)-2-phenylaceto hydrazide and EPAH = N'-ethylidene-2-phenylacetohydrazide were synthesized by the condensation of 2-phenylacetohydrazide with the corresponding aldehyde. The synthesized compounds were characterized by FTIR, 1D, and 2D NMR spectroscopy. The structure of the BPAH and PPAH were analyzed by single crystal X-ray diffraction analysis and in both crystallized compounds, the molecules adopted trans geometry around the -C[bond, double bond]N- (imine) functional group. To explore the pharmacological significance of these compounds, the binding ability of these compounds with Bovine Serum Albumin (BSA) was investigated using fluorescence spectroscopy. BPAH and PPAH showed the highest binding ability while EPAH, HBPAH, and FMPAH had lower binding ability to BSA molecules. Thermodynamic parameters ΔG, ΔH°, and ΔS° demonstrated that interactions of BSA with compounds BPAH, EPAH, FMAH, and HBPAH were exothermic while for PPAH it was endothermic. The negative enthalpy and entropy of the compounds BPAH, EPAH, FMAH, and HBPAH indicated that van der Waals' forces and hydrogen bonding played a major role in stabilizing the BSA binding with the molecules. Hydrophobic interactions were predominant in the binding of PPAH with BSA tends to interact with two sets of BSA binding sites with an increase in temperature.

11.
PeerJ Comput Sci ; 10: e1878, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660148

RESUMEN

Hyperparameter tuning plays a pivotal role in the accuracy and reliability of convolutional neural network (CNN) models used in brain tumor diagnosis. These hyperparameters exert control over various aspects of the neural network, encompassing feature extraction, spatial resolution, non-linear mapping, convergence speed, and model complexity. We propose a meticulously refined CNN hyperparameter model designed to optimize critical parameters, including filter number and size, stride padding, pooling techniques, activation functions, learning rate, batch size, and the number of layers. Our approach leverages two publicly available brain tumor MRI datasets for research purposes. The first dataset comprises a total of 7,023 human brain images, categorized into four classes: glioma, meningioma, no tumor, and pituitary. The second dataset contains 253 images classified as "yes" and "no." Our approach delivers exceptional results, demonstrating an average 94.25% precision, recall, and F1-score with 96% accuracy for dataset 1, while an average 87.5% precision, recall, and F1-score, with accuracy of 88% for dataset 2. To affirm the robustness of our findings, we perform a comprehensive comparison with existing techniques, revealing that our method consistently outperforms these approaches. By systematically fine-tuning these critical hyperparameters, our model not only enhances its performance but also bolsters its generalization capabilities. This optimized CNN model provides medical experts with a more precise and efficient tool for supporting their decision-making processes in brain tumor diagnosis.

12.
Angew Chem Int Ed Engl ; 63(18): e202320152, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38437457

RESUMEN

Dopant-free hole transporting materials (HTMs) is significant to the stability of perovskite solar cells (PSCs). Here, we developed a novel star-shape arylamine HTM, termed Py-DB, with a pyrene core and carbon-carbon double bonds as the bridge units. Compared to the reference HTM (termed Py-C), the extension of the planar conjugation backbone endows Py-DB with typical intermolecular π-π stacking interactions and excellent solubility, resulting in improved hole mobility and film morphology. In addition, the lower HOMO energy level of the Py-DB HTM provides efficient hole extraction with reduced energy loss at the perovskite/HTM interface. Consequently, an impressive power conversion efficiency (PCE) of 24.33 % was achieved for dopant-free Py-DB-based PSCs, which is the highest PCE for dopant-free small molecular HTMs in n-i-p configured PSCs. The dopant-free Py-DB-based device also exhibits improved long-term stability, retaining over 90 % of its initial efficiency after 1000 h exposure to 25 % humidity at 60 °C. These findings provide valuable insights and approaches for the further development of dopant-free HTMs for efficient and reliable PSCs.

13.
Chemosphere ; 355: 141743, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38513958

RESUMEN

Silver oxide doped iron oxide (Ag2O-Fe2O3) nanocatalyst was prepared and coated on cotton cloth (CC) as well as wrapped in sodium alginate (Alg) hydrogel. Ag2O-Fe2O3 coated CC (Ag2O-Fe2O3/CC) and Ag2O-Fe2O3 wrapped Alg (Ag2O-Fe2O3/Alg) were utilized as catalysts in reduction reaction of 4-nitrophenol (4-NP), congo red (CR), methylene blue (MB) and potassium ferricyanide (K3[Fe(CN)6]). Ag2O-Fe2O3/CC and Ag2O-Fe2O3/Alg were found to be effective and selective catalyst for the reaction of K3[Fe(CN)6]. Further amount of catalyst, K3[Fe(CN)6] quantity, amount of NaBH4, stability of catalyst and recyclability were optimized for the reaction of K3[Fe(CN)6] reduction. Ag2O-Fe2O3/Alg and Ag2O-Fe2O3/CC were appeared to be the stable catalysts by maintaining high activity during recyclability tests showing highest reaction rate constants (kapp) of 0.3472 and 0.5629 min-1, correspondingly. However, Ag2O-Fe2O3/CC can be easily recovered as compared to Ag2O-Fe2O3/Alg by simply removing from the reaction which is the main advantage of Ag2O-Fe2O3/CC. Moreover, Ag2O-Fe2O3/Alg and Ag2O-Fe2O3/CC were also examined in real samples and found useful for K3[Fe(CN)6] reduction involving real samples. The Ag2O-Fe2O3/CC nanocatalyst is a cost and time saving material for economical reduction of K3[Fe(CN)6] and environmental safety.


Asunto(s)
Alginatos , Compuestos Férricos , Ferricianuros , Nanocompuestos , Óxidos , Compuestos de Plata
14.
PeerJ Comput Sci ; 10: e1867, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38435590

RESUMEN

The accurate detection of brain tumors through medical imaging is paramount for precise diagnoses and effective treatment strategies. In this study, we introduce an innovative and robust methodology that capitalizes on the transformative potential of the Swin Transformer architecture for meticulous brain tumor image classification. Our approach handles the classification of brain tumors across four distinct categories: glioma, meningioma, non-tumor, and pituitary, leveraging a dataset comprising 2,870 images. Employing the Swin Transformer architecture, our method intricately integrates a multifaceted pipeline encompassing sophisticated preprocessing, intricate feature extraction mechanisms, and a highly nuanced classification framework. Utilizing 21 matrices for performance evaluation across all four classes, these matrices provide a detailed insight into the model's behavior throughout the learning process, furthermore showcasing a graphical representation of confusion matrix, training and validation loss and accuracy. The standout performance parameter, accuracy, stands at an impressive 97%. This achievement outperforms established models like CNN, DCNN, ViT, and their variants in brain tumor classification. Our methodology's robustness and exceptional accuracy showcase its potential as a pioneering model in this domain, promising substantial advancements in accurate tumor identification and classification, thereby contributing significantly to the landscape of medical image analysis.

15.
Curr Med Imaging ; 20: 1-17, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38389382

RESUMEN

BACKGROUND: Segmenting tumors in MRI scans is a difficult and time-consuming task for radiologists. This is because tumors come in different shapes, sizes, and textures, making them hard to identify visually. OBJECTIVE: This study proposes a new method called the enhanced regularized ensemble encoder-decoder network (EREEDN) for more accurate brain tumor segmentation. METHODS: The EREEDN model first preprocesses the MRI data by normalizing the intensity levels. It then uses a series of autoencoder networks to segment the tumor. These autoencoder networks are trained using back-propagation and gradient descent. To prevent overfitting, the EREEDN model also uses L2 regularization and dropout mechanisms. RESULTS: The EREEDN model was evaluated on the BraTS 2020 dataset. It achieved high performance on various metrics, including accuracy, sensitivity, specificity, and dice coefficient score. The EREEDN model outperformed other methods on the BraTS 2020 dataset. CONCLUSION: The EREEDN model is a promising new method for brain tumor segmentation. It is more accurate and efficient than previous methods. Future studies will focus on improving the performance of the EREEDN model on complex tumors.


Asunto(s)
Neoplasias Encefálicas , Redes Neurales de la Computación , Humanos , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
16.
J Environ Manage ; 353: 120206, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38325287

RESUMEN

Wastewater irrigation for vegetable cultivation is greatly concerned about the presence of toxic metals in irrigated soil and vegetables which causes possible threats to human health. This study aimed to ascertain the accumulation of heavy metals (HMs) in edible parts of vegetables irrigated with different stages of textile dyeing wastewater (TDW). Bio-concentration factor (BCF), Estimated daily intake (EDI), and target hazard quotient (THQ) were computed to estimate human health risks and speculate the hazard index (HI) of adults and children with the consumption of HMs contaminated vegetables at recommended doses. Five vegetables (red amaranth, Indian spinach, cauliflower, tomato, and radish) in a pot experiment were irrigated with groundwater (T1) and seven stages of TDW (T2∼T8) following a randomized complete block design (RCBD) with three replications. Among the TDW stages, T8, T7, T4, and T5 exhibited elevated BCF, EDI, THQ, and HI due to a rising trend in the accumulation of Pb, Cd, Cr, and Ni heavy metals in the edible portion of the red amaranth, followed by radish, Indian spinach, cauliflower, and tomato. The general patterns of heavy metal (HM) accumulation, regarded as vital nutrients for plants, were detected in the following sequence: Zn > Mn/Cu > Fe. Conversely, toxic metals were found to be Cd/Cr > Ni > Pb, regardless of the type of vegetables. Principal Component Analysis (PCA) identified T8, T7, and T4 of TDW as the primary contributors to the accumulation of heavy metals in the vegetables examined. Furthermore, the analysis of the heavy metals revealed that the BCF, THQ, and HI values for all studied metals were below 1, except for Pb. This suggests that the present consumption rates of different leafy and non-leafy vegetables, whether consumed individually or together, provide a low risk in terms of heavy metal exposure. Nevertheless, the consumption of T8, T7, and T4 irrigated vegetables, specifically Indian spinach alone or in combination with red amaranth and radish, by both adults and children, at the recommended rate, was found to pose potential health risks. On the other hand, T2, T3, and T6 irrigated vegetables were deemed safe for consumption. These findings indicated that the practice of irrigating the vegetables with T8, T7, and T4 stages of TDW has resulted in a significant buildup of heavy metals in the soils and edible parts of vegetables which are posing health risks to adults and children. Hence, it is imperative to discharge the T8, T7, and T4 stages of TDW after ETP to prevent the contamination of vegetables and mitigate potential health risks.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Solanum lycopersicum , Adulto , Niño , Humanos , Cadmio , Monitoreo del Ambiente , Contaminación de Alimentos/análisis , Plomo , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis , Verduras , Aguas Residuales
17.
Food Chem ; 445: 138792, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38387321

RESUMEN

Melamine, a typical nitrogen enriched organic compound exhibiting great potential in the industrial sector, is exploited as an adulterant to inflate protein levels in dairy products, can pose serious threats to humans and therefore necessitates its swift detection and precise quantification at its first exposure. In this investigation, sensitive and reliable sensor probes were fabricated using CuO nanoparticles and its nanocomposites (NCs) with carbon nanotubes (CNTs), carbon black (CB), and graphene oxide (GO) to promptly quantify melamine in dairy products. The optical, morphological, and structural characteristics of the CuO-CNT NCs were achieved using diverse instrumental techniques including UV-visible spectroscopy, transmission electron microscopy, X- ray diffraction, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy and etc. The fabrication of glassy carbon electrodes (GCE) was accomplished by coating CuO-CNT NCs through a binder (5 % nafion). These sensor probes demonstrated outstanding electrochemical sensor performance with CuO-CNT NCs/Nafion/GCE sensor probe in terms of very low limit of detection (0.27 nM), good linearity range (0.05-0.5 nM), and relatively high sensitivity (93.924 µA µM-1 m-2) for melamine under optimized experimental conditions. Furthermore, the performance of CuO-CNT NCs/Nafion/GCE coated sensor probes was practically validated for the selective melamine detection in the real sample analysis of commercially available milk brands, which revealed significant figures of merit in a very short response time of 10 s. From the results, it was concluded that the current study might be helpful in the development of an efficient commercial sensor based on ultra-sensitive transition metal oxides in the field of health care monitoring, food stuffs in a broader scale as well as food applications.


Asunto(s)
Polímeros de Fluorocarbono , Nanocompuestos , Nanotubos de Carbono , Triazinas , Humanos , Animales , Nanotubos de Carbono/química , Óxidos/química , Leche , Nanocompuestos/química , Técnicas Electroquímicas/métodos , Electrodos
18.
Chem Asian J ; : e202301107, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38419386

RESUMEN

The development of green hydrogen generation technologies is increasingly crucial to meeting the growing energy demand for sustainable and environmentally acceptable resources. Many obstacles in the advancement of electrodes prevented water electrolysis, long thought to be an eco-friendly method of producing hydrogen gas with no carbon emissions, from coming to fruition. Because of their great electrical conductivity, maximum supporting capacity, ease of modification in valence states, durability in hard environments, and high redox characteristics, transition metal oxides (TMOs) have recently captured a lot of interest as potential cathodes and anodes. Electrochemical water splitting is the subject of this investigation, namely the role of transition metal oxides as both active and supportive sites. It has suggested various approaches for the logical development of electrode materials based on TMOs. These include adjusting the electronic state, altering the surface structure to control its resistance to air and water, improving the flow of energy and matter, and ensuring the stability of the electrocatalyst in challenging conditions. In this comprehensive review, it has been covered the latest findings in electrocatalysis of the Oxygen Evolution Reaction (OER) and Hydrogen Evaluation Reaction (HER), as well as some of the specific difficulties, opportunities, and current research prospects in this field.

19.
Cureus ; 16(1): e52481, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38371011

RESUMEN

BACKGROUND: Live kidney donation is used to treat end-stage renal disease, but it poses risks and decision-making challenges for donors. This study examines kidney donors' long-term quality of life (QOL). METHODS:  We conducted a cross-sectional survey on kidney donors between 1982 and 2018. We used the Short Form-36 (SF-36) (Arabic version) to measure the donors' QOL. Out of 60 donors contacted, 44 agreed to participate and responded. Demographic information, donor-recipient relationships, and specific questions about the donation were collected and analyzed. RESULTS: The mean age of the donors was 50.1 ± 11.7 years at follow-up, and 26 (59.1%) were males. Most donors were siblings and parents, accounting for 36.4% (n=16) each. The time since the donation was 111.5 ± 97.1 months. All donors decided voluntarily to donate and all of them would do it again if given a chance. However, one donor (2.3%) complained that the donation had caused problems in his marriage, while six donors (13.4%) experienced clinically relevant distress, and two donors (4.5%) experienced financial disadvantages. Donors had high QOL scores, with a mean score of 73.1 and 96.9 (on a scale of 1-100) for the eight subscales. The highest score was for role social functioning, while the lowest was for energy/fatigue. The mean scores for the four fatigue subscales were low, ranging from 61.8 to 86.8. The lowest score was for feeling calm and reassured, while the highest was for feeling frustrated. In social functioning, the highest score was for the effect of mental health on work performance (97.2). We analyzed various demographic factors and their correlation with QOL and found no significant correlation in most domains regarding sociodemographic characteristics. CONCLUSIONS: Our research indicates that most kidney donors have had a positive experience over the past four decades. Both male and female donors of all ages reported good long-term QOL, further enhanced by recognition and support from their families and friends. These findings provide further support for our current policy on organ donation.

20.
RSC Adv ; 14(9): 5797-5811, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38362067

RESUMEN

In this study, poly(luminol-co-1,8-diaminonaphthalene) (PLim-DAN) was synthesized and subsequently modified with MWCNTs and CeO2 NPs. The synthesized nanocomposites were analyzed using IR, SEM, TEM, and XRD. Furthermore, a comprehensive set of thermal behavior measurements were taken using TGA/DTG analysis. Next, the electroactivity of the developed nanocomposites was tested as an electrochemical sensor to measure the concentration of Cr3+ ions in phosphate buffers. The GCE adapted with the PLim-DAN/CeO2/CNTs-10% nanocomposite (NC) exhibited the highest current response among the other compositions and copolymers. The fabricated nanocomposite sensor showed high sensitivity, with a value of 19.78 µA µM-1 cm-2, and a low detection limit of 4.80 ± 0.24 pM. The analytical performance was evaluated by plotting a current calibration curve versus the concentration of Cr3+ ions. It was found to be linear (R2 = 0.9908) over the range of 0.1 nM to 0.1 mM, identified as the linear dynamic range (LDR). This electrochemical sensor demonstrated that it could be a useful tool for environmental monitoring by accurately detecting and measuring carcinogenic Cr3+ ions in real-world samples.

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