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1.
Chem Asian J ; : e202300532, 2023 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-37544903

RESUMO

This study explores a water-splitting activity using a biphasic electrodeposited electrode on nickel foam (NF). The *Ni9 S8 /Cu7 S4 /NF electrode with citric acid reduction exhibits superior OER (oxygen evolution reaction) and HER (hydrogen evolution reaction) performance with reduced overpotential and a steeper Tafel slope. The *Ni9 S8 /Cu7 S4 /NF electrode displays the ultra-low overpotential value of 212 mV for OER and 109 mV for HER at the current density of 10 mA cm-2 . The Tafel slope of 25.4 mV dec-1 for OER and 108 mV dec-1 for HER was found from that electrode. The maximum electrochemical surface area (ECSA), lowest series resistance and lowest charge transfer resistance are found in citric acid reduced electrode, showing increased electrical conductivity and quick charge transfer kinetics. Remarkably, the *Ni9 S8 /Cu7 S4 /NF electrode demonstrated excellent stability for 80 hours in pure water splitting and 20 hours in seawater splitting. The synergistic effect of using bimetallic (Cu&Ni) sulfide and enhanced electrical conductivity of the electrode are caused by reduction of metal sulfide into metallic species resulting in improved water splitting performance.

2.
J Healthc Eng ; 2023: 1406545, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284488

RESUMO

Lymphoma and leukemia are fatal syndromes of cancer that cause other diseases and affect all types of age groups including male and female, and disastrous and fatal blood cancer causes an increased savvier death ratio. Both lymphoma and leukemia are associated with the damage and rise of immature lymphocytes, monocytes, neutrophils, and eosinophil cells. So, in the health sector, the early prediction and treatment of blood cancer is a major issue for survival rates. Nowadays, there are various manual techniques to analyze and predict blood cancer using the microscopic medical reports of white blood cell images, which is very steady for prediction and causes a major ratio of deaths. Manual prediction and analysis of eosinophils, lymphocytes, monocytes, and neutrophils are very difficult and time-consuming. In previous studies, they used numerous deep learning and machine learning techniques to predict blood cancer, but there are still some limitations in these studies. So, in this article, we propose a model of deep learning empowered with transfer learning and indulge in image processing techniques to improve the prediction results. The proposed transfer learning model empowered with image processing incorporates different levels of prediction, analysis, and learning procedures and employs different learning criteria like learning rate and epochs. The proposed model used numerous transfer learning models with varying parameters for each model and cloud techniques to choose the best prediction model, and the proposed model used an extensive set of performance techniques and procedures to predict the white blood cells which cause cancer to incorporate image processing techniques. So, after extensive procedures of AlexNet, MobileNet, and ResNet with both image processing and without image processing techniques with numerous learning criteria, the stochastic gradient descent momentum incorporated with AlexNet is outperformed with the highest prediction accuracy of 97.3% and the misclassification rate is 2.7% with image processing technique. The proposed model gives good results and can be applied for smart diagnosing of blood cancer using eosinophils, lymphocytes, monocytes, and neutrophils.


Assuntos
Neoplasias Hematológicas , Leucemia , Neoplasias , Humanos , Masculino , Feminino , Leucócitos , Aprendizado de Máquina , Neoplasias/diagnóstico , Leucemia/diagnóstico , Processamento de Imagem Assistida por Computador/métodos
3.
Med Dosim ; 48(4): 211-215, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37188547

RESUMO

To investigate the feasibility of volumetric modulated arc therapy (VMAT) delivery for whole breast irradiation with a 5-fraction regimen according to the FAST-Forward trial. Recently, we treated 10 patients with carcinoma of the left breast after breast conserving surgery. The dose prescription to the PTV was 26 Gy in 5 fractions. Treatment plans were produced using a VMAT technique with the Eclipse treatment planning system for 6 MV flattening filter (FF) and FF free (FFF) beams. Dose volume histograms (DVHs) for the PTV and the organs at risk (OARs), the ipsilateral lung and heart, were compared with the dose constraints specified in the FAST-Forward trial (PTV, D95 > 95%, D5 < 105%, D2 < 107% and Dmax < 110%; ipsilateral lung, D15 < 8Gy; Heart, D30 < 1.5Gy and D5 < 7Gy). Furthermore, conformity index (CI), homogeneity index (HI) and dose to the heart, contralateral lung, contralateral breast, and left anterior descending artery (LAD), were also assessed. Mean ± SD D95(%), D5(%), D2(%), and Dmax (%) for PTV were 97.75 ± 1.12, 105.2 ± 0.82, 105.90 ± 0.89, 109.36 ± 1.00 (FF) and 96.46 ± 0.75, 103.97 ± 0.97, 104.70 ± 1.09, 108.58 ± 1.33 (FFF) respectively. The mean ± SD CI was 1.07 ± 0.05 (FF), 1.048 ± 0.06 (FFF) and HI was 0.11 ± 0.02 (FF), 0.10 ± 0.02 (FFF). Dose constraints for OARs were met for both treatment techniques. However, D15 (Gy) for ipsilateral lung was 3.0% lower with FFF beams. In contrast, D5 (Gy) for heart was 9.0% higher with FFF beams. The dose difference between FF and FFF beams for other OARs such as contralateral lung-D10 (Gy) contralateral breast-D5 (Gy) and LAD was up to 6.0%. Both FF and FFF methods met the acceptable criteria. However, the treatment plans with FFF mode were more conformal and provided greater target homogeneity.


Assuntos
Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Humanos , Radioterapia de Intensidade Modulada/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Pulmão
4.
Nanomaterials (Basel) ; 11(12)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34947812

RESUMO

Perovskite solar cells (PSCs) have already achieved efficiencies of over 25%; however, their instability and degradation in the operational environment have prevented them from becoming commercially viable. Understanding the degradation mechanism, as well as improving the fabrication technique for achieving high-quality perovskite films, is crucial to overcoming these shortcomings. In this study, we investigated details in the changes of physical properties associated with the degradation and/or decomposition of perovskite films and solar cells using XRD, FESEM, EDX, UV-Vis, Hall-effect, and current-voltage (I-V) measurement techniques. The dissociation, as well as the intensity of perovskite peaks, have been observed as an impact of film degradation by humidity. The decomposition rate of perovskite film has been estimated from the structural and optical changes. The performance degradation of novel planner structure PSCs has been investigated in detail. The PSCs were fabricated in-room ambient using candle soot carbon and screen-printed Ag electrode. It was found that until the perovskite film decomposed by 30%, the film properties and cell efficiency remained stable.

5.
Polymers (Basel) ; 13(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34771242

RESUMO

This study explores the possibility of transforming lignocellulose-rich agricultural waste materials into value-added products. Cellulose was extracted from an empty fruit bunch of oil palm and further modified into carboxymethyl cellulose (CMC), a water-soluble cellulose derivative. The CMC was then employed as the polymeric content in fabrication of solid polymer electrolyte (SPE) films incorporated with lithium iodide. To enhance the ionic conductivity of the solid polymer electrolytes, the compositions were optimized with different amounts of glycerol as a plasticizing agent. The chemical and physical effects of plasticizer content on the film composition were studied by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analysis. FTIR and XRD analysis confirmed the interaction plasticizer with the polymer matrix and the amorphous nature of fabricated SPEs. The highest ionic conductivity of 6.26 × 10-2 S/cm was obtained with the addition of 25 wt % of glycerol. By fabricating solid polymer electrolytes from oil palm waste-derived cellulose, the sustainability of the materials can be retained while reducing the dependence on fossil fuel-derived materials in electrochemical devices.

6.
Materials (Basel) ; 14(21)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34771914

RESUMO

In this study, phytochemical assisted nanoparticle synthesis was performed using Muntingia calabura leaf extracts to produce copper oxide nanoparticles (CuO NPs) with interesting morphology. Scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis of the biosynthesized CuO NPs reveal formation of distinct, homogeneous, and uniform sized CuO nanorods structure with thickness and length of around 23 nm and 79 nm, respectively. Based on Fourier-transform infrared (FTIR) analysis, the unique combinations of secondary metabolites such as flavonoid and polyphenols in the plant extract are deduced to be effective capping agents to produce nanoparticles with unique morphologies similar to conventional chemical synthesis. X-ray diffraction (XRD) analysis verified the monoclinical, crystalline structure of the CuO NPs. The phase purity and chemical identity of the product was consolidated via X-Ray photoelectron spectroscopy (XPS) and Raman spectroscopic data which indicate the formation of a single phase CuO without the presence of other impurities. The direct and indirect optical band gap energies of the CuO nanorods were recorded to be 3.65 eV and 1.42 eV.

7.
Financ Res Lett ; 42: 101882, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33312079

RESUMO

This study investigates oil price risk exposure of financial and non-financial industries around the world during the COVID-19 pandemic. The empirical results show that oil supply industries benefit from positive shocks to oil price risk in general, whereas oil user industries and financial industries react negatively to positive oil price shocks. The COVID-19 outbreak appears to moderate the oil price risk exposure of both financial and non-financial industries. This brings important implications in risk management of energy risk during the pandemic.

8.
Polymers (Basel) ; 12(9)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32972016

RESUMO

A starch-resorcinol-formaldehyde (RF)-lithium triflate (LiTf) based biodegradable polymer electrolyte membrane was synthesized via the solution casting technique. The formation of RF crosslinks in the starch matrix was found to repress the starch's crystallinity as indicated by the XRD data. Incorporation of the RF plasticizer improved the conductivity greatly, with the highest room-temperature conductivity recorded being 4.29 × 10-4 S cm-1 achieved by the starch:LiTf:RF (20 wt.%:20 wt.%:60 wt.%) composition. The enhancement in ionic conductivity was an implication of the increase in the polymeric amorphous region concurrent with the suppression of the starch's crystallinity. Chemical complexation between the plasticizer, starch, and lithium salt components in the electrolyte was confirmed by FTIR spectra.

9.
Sci Rep ; 10(1): 10852, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616768

RESUMO

As synthetic antioxidants that are widely used in foods are known to cause detrimental health effects, studies on natural additives as potential antioxidants are becoming increasingly important. In this work, the total phenolic content (TPC) and antioxidant activity of Ficus carica Linn latex from 18 cultivars were investigated. The TPC of latex was calculated using the Folin-Ciocalteu assay. 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and ferric ion reducing antioxidant power (FRAP) were used for antioxidant activity assessment. The bioactive compounds from F. carica latex were extracted via maceration and ultrasound-assisted extraction (UAE) with 75% ethanol as solvent. Under the same extraction conditions, the latex of cultivar 'White Genoa' showed the highest antioxidant activity of 65.91% ± 1.73% and 61.07% ± 1.65% in DPPH, 98.96% ± 1.06% and 83.04% ± 2.16% in ABTS, and 27.08 ± 0.34 and 24.94 ± 0.84 mg TE/g latex in FRAP assay via maceration and UAE, respectively. The TPC of 'White Genoa' was 315.26 ± 6.14 and 298.52 ± 9.20 µg GAE/mL via the two extraction methods, respectively. The overall results of this work showed that F. carica latex is a potential natural source of antioxidants. This finding is useful for further advancements in the fields of food supplements, food additives and drug synthesis in the future.


Assuntos
Antioxidantes/farmacologia , Ficus/química , Flavonoides/farmacologia , Látex/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Solventes/química , Ficus/classificação
10.
Sci Rep ; 6: 38906, 2016 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-28008923

RESUMO

In this paper, we report a compact and ultra-wide band antenna on a flexible substrate using the 5-(4-(perfluorohexyl)phenyl)thiophene-2-carbaldehyde compound for microwave imaging. In contrast to other microwave based imaging systems, such as an array of 16 antennas, we proposed a bi-static radar based imaging system consisting of two omnidirectional antennas, which reduces complexity and the overall dimension. The proposed compact antennas are 20 × 14 mm2 and designed for operating at frequencies from 4 to 6 GHz. To allow for implantation into a bra, the electromagnetic performances of the antennas must be considered in bending conditions. In comparison with the recently reported flexible antennas, we demonstrated both electromagnetic performance and imaging reconstruction for bending conditions. For the proof of concept, the electromagnetic performances both at flat and bending conditions have been verified using a homogeneous multilayer model of the human breast phantom. Our results demonstrate that the antenna, even at bending conditions, exhibits an excellent omni-directional radiation pattern with an average efficiency above 70% and average gain above 1 dBi, within the operational frequency band. The comprehensive aim of the realized antenna is to design a biodegradable and wearable antenna-based bra for early breast cancer detection in the future.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Vestuário , Diagnóstico por Imagem , Micro-Ondas , Dispositivos Eletrônicos Vestíveis , Diagnóstico por Imagem/instrumentação , Diagnóstico por Imagem/métodos , Feminino , Humanos
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