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1.
J Clin Neurol ; 20(4): 378-384, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38951972

RESUMEN

BACKGROUND AND PURPOSE: Repetitive transcranial magnetic stimulation (rTMS) of the cerebellar hemisphere represents a new option in treating essential tremor (ET) patients. We aimed to determine the efficacy of cerebellar rTMS in treating ET using different protocols regarding the number of sessions, exposure duration, and follow-up duration. METHODS: A randomized sham-controlled trial was conducted, in which 45 recruit patients were randomly allocated to 2 groups. The first (active group) comprised 23 patients who were exposed to 12 sessions of active rTMS with 900 pulses of 1-Hz rTMS at 90% of the resting motor threshold daily on each side of the cerebellar hemispheres over 4 weeks. The second group (sham group) comprised 22 patients who were exposed to 12 sessions of sham rTMS. Both groups were reassessed at baseline and after 1 day, 1 month, 2 months, and 3 months using the Fahn-Tolosa-Marin tremor-rating scale (FTM). RESULTS: Demographic characteristics did no differ between the two groups. There were significant reductions both in FTM subscores A and B and in the FTM total score in the active-rTMS group during the period of assessment and after 3 months (p=0.031 and 0.011, respectively). However, subscore C did not change significantly from baseline when assessed at 2 and 3 months (p=0.073 and 0.236, respectively). Furthermore, the global assessment score was significantly higher in the active-rTMS group (p>0.001). CONCLUSIONS: Low-frequency rTMS over the cerebellar cortex for 1 month showed relative safety and long-lasting efficacy in patients with ET. Further large-sample clinical trials are needed that include different sites of stimulation and longer follow-ups.

2.
Materials (Basel) ; 17(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38930259

RESUMEN

In the present work, magnesium oxide (MgO) and lead oxide (PbO) nanoparticles were prepared by the co-precipitation method. Their structural parameters and morphology were investigated using XRD, HRTEM, and FTIR. The formation of the phases was seen to have small average crystallite sizes and an orthorhombic crystal structure for both MgO and PbO nanoparticles. The results of HR-TEM showed irregularly shaped nanoparticles: quasi-spherical or rod-like shapes and spherical-like shapes for MgO and PbO nanoparticles, respectively. The produced nanoparticles' size using X-ray diffraction analysis was found to be 17 nm and 41 nm for MgO and PbO nanoparticles, respectively. On the other hand, it was observed from the calculations that the optical band gap obeys an indirect allowed transition. The calculated values of the band gap were 4.52 and 4.28 eV for MgO and PbO NPs, respectively. The MB was extracted from the wastewater using the prepared composites via absorption. Using a variety of kinetic models, the adsorptions were examined. Out of all the particles, it was discovered that the composites were best. Furthermore, of the models currently under consideration, the pseudo-second-order model best fit the degradation mechanism. The resultant composites could be beneficial for degrading specific organic dyes for water purification, as well as applications needing a wider optical band gap.

3.
Phys Chem Chem Phys ; 26(25): 17817-17829, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38884203

RESUMEN

There is currently a great deal of interest in realizing localized surface plasmon resonances (LSPRs) in two distinct windows in the near-infrared (NIR) spectrum for in vivo biosensing and medical applications, the biological window (BW) I and II (BW I, 700-900 nm; BW II, 1000-1700 nm). This study aims to demonstrate that LSPRs of Ga-doped ZnO (GZO) core-silver (Ag) shell structures exhibit promising features for biological applications in the NIR BW I and II. Here, we study three different shapes for nanoshells: the core-shell nanosphere, nanorod, and nanodisk. In the calculation of the optical response of these nanoshells, an effective medium approach is first used to reduce the dielectric function of a nanoshell to that of an equivalent homogenous NP with an effective dielectric function. Then, the LSPR spectra of nanoshells are calculated using the modified long-wavelength approximation (MLWA), which corrects the polarizability of the equivalent NP as obtained by Gans theory. Through numerical investigations, we examine the impacts of the core and shell sizes of the proposed nanoshells as well as the medium refractive index on the position and line width of the plasmon resonance peaks. It is shown that the plasmon resonances of the three proposed nanoshells exhibit astonishing resonance tunability in the NIR region by varying their geometrical parameters. Specifically, the improved spectrum characteristics and tunability of its plasmon resonances make the GZO-Ag nanosphere a more viable platform for NIR applications than the spherical metal colloid. Furthermore, we demonstrate that the sensitivity and figure of merit (FOM) of the plasmon resonances may be significantly increased by using GZO-Ag nanorods and nanodisks in place of GZO-Ag nanospheres. It is found that the optical properties of the transverse plasmon resonance of the GZO-Ag nanodisk are superior to all plasmon resonances produced by the GZO-Ag nanorods and GZO-Ag nanospheres in terms of sensitivity and FOM. The FOM of the transverse plasmon mode of the GZO-Ag nanodisk is almost two orders of magnitude higher than that of the longitudinal and transverse plasmon modes of the GZO-Ag nanorod in BW I and BW II. And it is 1.5 and 2 times higher than the plasmon resonance FOM of GZO-Ag nanospheres in BW I and BW II, respectively.


Asunto(s)
Técnicas Biosensibles , Nanosferas , Nanotubos , Plata , Resonancia por Plasmón de Superficie , Óxido de Zinc , Plata/química , Nanotubos/química , Óxido de Zinc/química , Técnicas Biosensibles/métodos , Nanosferas/química , Galio/química , Rayos Infrarrojos
4.
Bioresour Bioprocess ; 11(1): 3, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38647852

RESUMEN

Development of nano-enabled fertilizers from green waste is one of the effective options to enhance global agricultural productions and minimize environmental pollution. In this study, novel, eco-friendly and cost-effective nano- enabled fertilizers (NEF) were synthesized using the planetary ball milling procedure. The NEF (nDPF1and nDPF2) were prepared by impregnation of nanostructured date palm pits (nDPP) with (KH2PO4 + MgO) at 1:1 and 3:1 (w/w) ratios respectively. The nDPP, nDPF1 and nDPF2 were extensively characterized. The produced nano-fertilizers enhanced soil water retention capacity with nDPF2 being the most effective. The water retention capacity of nDPF2 treated soil was 5.6 times higher than that of soil treated with conventional fertilizers. In addition, the nDPF2 exhibited superior sustained lower release rates of P, K and Mg nutrients for longer release periods in comparison with the conventional fertilizers. For instance, P cumulative release percentages from conventional fertilizers, nDPF1 and nDPF2 in soil reached 22.41%, 10.82 and 8.9% respectively within 384 h. Findings from FTIR and XPS analyses suggested that hydrogen bonding and ligand exchange were the main interaction mechanisms of PO4-K-Mg ions with nDPP surface. The released kinetics data of the NEF revealed that power function was the best suitable model to describe the kinetics of P, K and Mg release data from NEF in water and soil. Pot study ascertained that the nano-enabled fertilizers (nDPF1 and nDPF2) significantly promoted biomass production and nutrient uptake of maize plants as compared to commercial fertilizer treated plants. The present work demonstrated the potential of NEF to increase nutrients uptake efficiency, mitigate moisture retention problem in arid soils and reduce nutrients loss through leaching and safeguard the environment.

6.
Sci Rep ; 14(1): 5691, 2024 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-38454001

RESUMEN

Nanotechnology has emerged as a promising approach for the controlled release of nutrients, particularly phosphorus and potassium. These essential plant nutrients are often applied in excess, leading to environmental pollution and loss of efficiency in crop production. Innovative economic and highly efficient fertilizers are urgently needed to achieve the targeted crop production worldwide in the presence of limited land and water resources. Therefore, in this study, novel, eco-friendly, cost-effective and enhanced efficiency nano-enabled fertilizers, NEF (nWTF1and nWTF2) were synthesized by impregnation of nanostructured water treatment residuals (nWTR) with (KH2PO4 + MgO) at 1:1 and 3:1 (w/w) ratios respectively using a planetary ball mill. The nWTR, nWTF1 and nWTF2 were extensively characterized. The water retention behavior and the sustained release of nutrients from the fabricated nano-enabled fertilizers (nWTF1 and nWTF2) in distilled water and sandy soil were investigated and monitored over time. The water retention capacity of the soil treated with nWTF2 after 26 days was 9.3 times higher than that of soil treated with conventional fertilizer. In addition, the nWTF2 exhibited lower release rates of P, K and Mg nutrients for longer release periods in comparison with the conventional fertilizers. This is a significant advantage over traditional fertilizers, which release nutrients quickly and can lead to leaching and nutrient loss. The main interaction mechanisms of PO4-K-Mg ions with nWTR surface were suggested. The results of the kinetics study revealed that power function was the best suitable model to describe the kinetics of P, K and Mg release data from NEF in water and soil. The produced NEF were applied to Zea maize plants and compared to commercial chemical fertilizer control plants. The obtained results revealed that the nano-enabled fertilizers (nWTF1 and nWTF2) significantly promoted growth, and P content compared with the commercial chemical fertilizer treated plants. The present work demonstrated the power of nano enabled fertilizers as efficient and sustained release nano-fertilizers for sustainable agriculture and pollution free environment.


Asunto(s)
Agua Potable , Fertilizantes , Fertilizantes/análisis , Residuos Industriales , Preparaciones de Acción Retardada , Agricultura/métodos , Suelo/química , Nutrientes , Nitrógeno
7.
J Neurol ; 271(3): 1124-1132, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38070031

RESUMEN

BACKGROUND: Multiple sclerosis (MS) is a chronic demyelinating neurodegenerative disorder. Elevated levels of pro-inflammatory mediators and some oxidative stress parameters can accelerate the demyelination process. We aimed to investigate the efficacy and safety of metformin as an adjuvant therapy to interferon beta 1a (IFNß-1a) in relapsing-remitting multiple sclerosis (RRMS) patients. METHOD: Eighty RRMS patients were equally divided into 2 groups: the intervention group receiving IFNß-1a plus 2 gm of metformin once daily and the control group receiving IFNß-1a alone. Interleukin 17 (IL17), interleukin 22 (IL22), malondialdehyde (MDA), T2 lesions in magnetic resonance imaging (MRI) and expanded disability status scale (EDSS) were assessed at the baseline and then after 6 months. RESULTS: At baseline, there were no statistically significant differences between the two groups (p > 0.05). After 6 months, the change in the median (interquartile range) of the results for both the intervention and control group were; IL17 (- 1.39 (4.19) vs - 0.93 (5.48), p = 0.48), IL22 (- 0.14 (0.48) vs - 0.09 (0.6), p = 0.53), and EDSS (0 vs 0, p = 1), respectively. The mean (standard deviation) change in MDA for the intervention and control group was - 0.93 (2.2) vs - 0.5 (2.53), p = 0.038, respectively. For MRI results, 21 patients had stationary and regressive course and 1 patient had a progressive course in the intervention arm vs 12 patients had stationary and regressive course and 4 had a progressive course in the control arm, p = 0.14. CONCLUSION: Adding metformin to IFNß-1a demonstrated a potential effect on an oxidative stress marker (MDA). However, there is no statistically significant effect on immunological, MRI and clinical outcomes. We recommend larger scale studies to confirm or negate these findings. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT05298670, 28/3/2022.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Humanos , Adyuvantes Inmunológicos/uso terapéutico , Enfermedad Crónica , Interferón beta-1a/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/patología , Estudios Prospectivos , Recurrencia , Resultado del Tratamiento
8.
Sci Rep ; 13(1): 21901, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-38081934

RESUMEN

Environmental pollution is a global phenomenon and troublesome fact that poses a grave risk to all living entities. Via coupling carbonaceous feedstocks with outstanding microbial activity, kinetic experiments were established using the consortium of Proteus mirabilis and Raoultella planticola, biochar-derived sunflower seed husk (SHB) and rice straw (RSB), and their composites, which investigated at 30 °C (150 rpm) to eliminate 700 mg L-1 lead (120 h) and phenol (168 h) from synthetic wastewater. The derived biochars physicochemical properties of were studied. According to adsorption capacity (qe), consortium-SHB composites and consortium-RSB composites removed lead completely (70 mg g-1) within 48 h and 66 h, respectively. Besides, phenol was remediated entirely after 42 h and 48 h by both composite systems (69.90 mg g-1), respectively, comparing with bacterial consortium only or parent SHB and RSB. Moreover, four kinetic models were studied to describe the bioremediation process. Fractional power and Elovich models could be recommended for describing the adsorption kinetics for lead and phenol removal by the studied biomaterials with high correlation coefficient (R2 ≥ 0.91 for Pb2+ and ≥ 0.93 for phenol) and lower residual root mean square error (RMSE) and chi-square (X2). Overall, bacterial consortium-biochar composites exhibited greater remediation of lead and phenol than the sum of each single bacterial consortium and biochar systems; reflecting synergistic interaction of adsorptive capability of biochar and metabolic performance of bacterial consortium, as denoted by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The current study addressed the successful design of employing functional remediating consortium immobilized on waste biomass-derived biochar as a conducive alternative eco-sorbent and economic platform to detoxify organic and inorganic pollutants.


Asunto(s)
Helianthus , Oryza , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Biodegradación Ambiental , Carbón Orgánico/química , Cinética , Plomo , Fenol/química , Fenoles , Semillas/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
9.
Nanoscale Adv ; 5(24): 7086, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38059045

RESUMEN

Expression of concern for 'Tin-zinc-oxide nanocomposites (SZO) as promising electron transport layers for efficient and stable perovskite solar cells' by Ahmed E. Shalan et al., Nanoscale Adv., 2019, 1, 2654-2662, DOI: https://doi.org/10.1039/C9NA00182D.

10.
RSC Adv ; 13(47): 33061, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37956268

RESUMEN

Expression of concern for 'Concordantly fabricated heterojunction ZnO-TiO2 nanocomposite electrodes via a co-precipitation method for efficient stable quasi-solid-state dye-sensitized solar cells' by Ahmed Esmail Shalan et al., RSC Adv., 2015, 5, 103095-103104, DOI: 10.1039/C5RA21822E.

11.
Sci Rep ; 13(1): 20621, 2023 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-37996572

RESUMEN

Calcareous soils are characterized by a high calcium carbonate content (calcite), which plays a crucial role in the soil structure, plant growth, and nutrient availability. The high content of CaCO3 leads to the increment of the soil alkalinity, which results in a lowering of the nutrient availability causing a challenge for the agriculture in these soils. In this study, the calcite-solubilizing potential of the diazotrophic Azotobacter salinestris YRNF3 was investigated in vitro as a probable bio-agent for enhancing the calcareous soils properties such as soil pH and nutrient availability. Twelve diazotrophic bacterial strains were isolated from wheat rhizosphere collected from different wheat-cultivated fields in five Egyptian governorates. Using Nessler's reagent, all isolated bacterial strains were found to have the ability to produce ammonia. By amplification of nifH gene, a PCR product of 450 bp was obtained for all isolated bacterial strains. For each isolate, three biological and three technical replicates were applied. All isolated diazotrophic bacteria were qualitatively screened for their calcite-solubilizing ability. To quantitatively investigate the calcite-solubilizing potential of A. salinestris YRNF3 in vitro, changes in the contents of soluble calcium (Ca2+), bicarbonate (HCO3-), total nitrogen (TN), total protein (TP), and pH were daily measured in its culture filtrate along 10 days of incubation. The results showed that the pH values in the culture filtrate ranged from 5.73 to 7.32. Concentration of Ca2+ and HCO3- in the culture filtrate significantly decreased with the increment in the incubation time, while concentration of TN increased along the time. The highest TN concentration (0.0807 gL-1) was observed on days 4 and 5, compared to that of the day 0 (0.0014 gL-1). Content of TP in the culture filtrate also significantly increased along the incubation period. The highest TP content was recorded in day 4 (0.0505%), while no TP content was recorded on day 0. Furthermore, data obtained revealed that A. salinestris YRNF3 produced acid phosphatase at low activity (5.4 U mL-1). HPLC analysis of the culture filtrate indicated production of different organic acids, namely lactic acid (82.57 mg mL-1), formic acid (46.8 mg mL-1), while acetic acid was detected in a low quantity (3.11 mg mL-1). For each analysis, three replicates of each treatment were analyzed. Means of the tested treatments were compared using Tukey's HSD test at p ≤ 0.05. In conclusion, findings of this work suggested that A. salinestris YRNF3 has the potential to be a probable bioagent to be used for the reclamation of the calcareous soils by solubilizing CaCO3, improving soil fertility, and promoting plant growth. However, further studies are needed to investigate its field application and their long-term effects on the soil properties and plant productivity. To the best of the author's knowledge, this is the first study reporting the calcite-solubilizing ability of a nitrogen-fixing bacteria. Having these two abilities by one microorganism is a unique feature, which qualifies it as a promising bioagent for reclamation of the calcareous soils.


Asunto(s)
Azotobacter , Suelo , Suelo/química , Carbonato de Calcio/metabolismo , Bacterias , Excipientes/metabolismo , Microbiología del Suelo
12.
RSC Adv ; 13(47): 32927, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-38025877

RESUMEN

Expression of Concern for 'Solid-state dye-sensitized solar cells based on Zn1-xSnxO nanocomposite photoanodes' by Ayat Nasr El-Shazly et al., RSC Adv., 2018,8, 24059-24067, DOI: https://doi.org/10.1039/c8ra02852d.

13.
Acta Med Indones ; 55(2): 211-214, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37524599

RESUMEN

Progressive multifocal leukoencephalopathy (PML) is a rare, life-threatening, infectious, lytic, demyelinating disease that results from reactivation of the virulent JC polyomavirus (JCV) "major opportunistic infection" in immunosuppressed individuals. We reported a case of a young girl who presented with new onset focal neurological defect, evaluated, and laboratory and radiological findings in the context of a clinical setting confirmed HIV-related-PML infection. However, remyelination does not occur, the patients may develop complications in the long term including cognitive impairment, sensory deficits, motor deficits, and disturbances in balance. We must increase our knowledge about HIV- related PML in any patient with reduced immunity and who presented with new onset neurological defect.

14.
Radiol Case Rep ; 18(6): 2268-2273, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37128253

RESUMEN

Hemolytic uremic syndrome (HUS) is a multisystem disorder generally seen in children and young adults, manifesting with the symptomatic triad of thrombocytopenia, hemolytic anemia, and acute kidney injury. These symptoms are often preceded by a prodrome of bloody diarrhea, vomiting, fever, and weakness. HUS is an exceedingly rare entity, with less than 1.5 per 100,000 people affected annually. HUS with central nervous system (CNS) manifestations constitutes approximately 20%-50% of cases and often presents with seizures, altered level of consciousness, and brainstem symptoms. CNS involvement in HUS is a major cause of acute morbidity and mortality; therefore, timely diagnosis and treatment are crucial in the management of these cases. Neuroimaging plays a critical role in the diagnosis; however, it might be very challenging in a large number of cases because studies that report the typical neuroradiologic features of brain injury in cases with HUS are not commonly available. Herein, we demonstrate in a case-based approach, the importance of combining clinical suspicion with different radiologic modalities to better characterize HUS cases with CNS involvement, as well as demonstrate how the early start of meticulous supportive therapy can lead to a favorable outcome even when severe brain involvement is evident on acute imaging studies. Furthermore, we provide an illustrated overview of the current theories that explain the neurologic involvement in HUS, as well as the commonly affected brain areas and how this entity can be radiologically differentiated from other potential diagnoses.

15.
Sci Rep ; 13(1): 8197, 2023 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-37210401

RESUMEN

The bioavailability of trace metals in soils poses a major threat to the environment, especially with massive mineral fertilizers added to increase plant yield. A plot experiment was conducted for the effectiveness evaluation of compost and vermicompost, recycled from agro-industrial wastes, in immobilizing chromium, cadmium, and lead added to calcareous soil (artificially contaminated). Moreover, immobilization efficiency was compared to the natural occurrence of these metals in the soil without metal addition (uncontaminated soil). In both soils, amendments and mineral fertilizers were applied at three different levels alone and combined to each other. The experimental design was arranged in factorial complete randomized blocks using contamination, organic and mineral fertilizer levels, and their combination as categorical factors. The distribution of metal fractions and their bioavailability in soils and bioaccumulation in wheat grains were evaluated. Soil alkalinity, the contents of soil organic carbon and nitrogen, available phosphorus, and soil micronutrients were significantly improved under vermicompost and compost compared to mineral fertilizer and control. Vermicompost was more effective than compost in reducing metals bioavailability in contaminated soils by increasing the immobilized organic fractions, but it regressed when combined with mineral fertilizers. The bioavailability of the naturally occurring metal levels in uncontaminated soil did not change significantly compared to contaminated soil. Likewise, wheat yield, plant biomass, and nutrient enrichment in wheat grains improved due to enhanced soil nutrient availability. These composted agro-industrial residues, by-products from food industries, can be classified as environmentally-friendly soil amendments for their great potential to enrich soil nutrients, reduce mineral fertilizer addition, enhance plant growth, and stabilize Cr, Cd, and Pb in contaminated calcareous soils under wheat plants.


Asunto(s)
Compostaje , Metales Pesados , Contaminantes del Suelo , Suelo/química , Cadmio , Fertilizantes/análisis , Plomo , Carbono , Contaminantes del Suelo/análisis , Minerales , Metales Pesados/análisis
17.
Materials (Basel) ; 16(10)2023 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-37241347

RESUMEN

This work comprehensively studies both the photocatalytic degradation and the adsorption process of Congo red dye on the surface of a mixed-phase copper oxide-graphene heterostructure nanocomposite. Laser-induced pristine graphene and graphene doped with different CuO concentrations were used to study these effects. Raman spectra showed a shift in the D and G bands of the graphene due to incorporating copper phases into the laser-induced graphene. The XRD confirmed that the laser beam was able to reduce the CuO phase to Cu2O and Cu phases, which were embedded into the graphene. The results elucidate incorporating Cu2O molecules and atoms into the graphene lattice. The production of disordered graphene and the mixed phases of oxides and graphene were validated by the Raman spectra. It is noted from the spectra that the D site changed significantly after the addition of doping, which indicates the incorporation of Cu2O in the graphene. The impact of the graphene content was examined with 0.5, 1.0, and 2.0 mL of CuO. The findings of the photocatalysis and adsorption studies showed an improvement in the heterojunction of copper oxide and graphene, but a significant improvement was noticed with the addition of graphene with CuO. The outcomes demonstrated the compound's potential for photocatalytic use in the degradation of Congo red.

18.
Foods ; 12(7)2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37048286

RESUMEN

Opuntia spp. are crops well adapted to adverse environments and have great economic potential. Their constituents, including fruits, cladodes, and flowers, have a high nutritional value and are rich in value-added compounds. Cladodes have an appreciable content in dietary fiber, as well as bioactive compounds such as kaempferol, quercetin, and isorhamnetin. Fruits are a major source of bioactive compounds such as phenolic acids and vitamin C. The seeds are mainly composed of unsaturated fatty acids and vitamin E. The flowers are also rich in phenolic compounds. Therefore, in addition to their traditional uses, the different plant fractions can be processed to meet multiple applications in the food industry. Several bakery products have been developed with the incorporation of cladode flour. Pectin and mucilage obtained from cladodes can act as edible films and coatings. Fruits, fruit extracts, and fruit by-products have been mixed into food products, increasing their antioxidant capacity and extending their shelf life. Betalains, obtained from fruits, can be used as food colorants and demonstrate promising applications as a sensor in food packaging. This work reviews the most valuable components of the different fractions of this plant and emphasizes its most recent food applications, demonstrating its outstanding value.

19.
RSC Adv ; 13(14): 9154-9167, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36950705

RESUMEN

GeSn compounds have made many interesting contributions in photodetectors (PDs) over the last ten years, as they have a detection limit in the NIR and mid-IR region. Sn incorporation in Ge alters the cut off wavelength. In the present article, p-i-n structures based on GeSn junctions were fabricated to serve as PDs. Arsine (As) is incorporated to develop n-GeSn compounds via a metal induced crystallization (MIC) process followed by i-GeSn on p-Si wafers. The impact of As and Sn doping on the strain characteristics of GeSn has been studied with high resolution transmission electron microscopy (HRTEM), X-ray diffraction and Raman spectroscopy analyses. The direct transitions and tuning of their band energies have been investigated using diffuse reflectance UV-vis spectroscopy and photoluminescence (PL). The barrier height and spectral responsivity have been controlled with incorporation of As. Variation of As incorporation into GeSn Compounds shifted the Raman peak and hence affected the strain in the Ge network. UV-vis spectroscopy showed that the direct transition energies are lowered as the Ge-As bonding increases as illustrated in Raman spectroscopy investigations. PL and UV-vis spectroscopy of annealed heterostructures at 500 °C showed that there are many transition peaks from the UV to the NIR region as result of oxygen vacancies in the Ge network. The calculated diode parameters showed that As incorporation leads to an increase of the height barrier and thus dark current. Spectral response measurements show that the prepared heterojunctions have spectral responses in near UV and NIR regions that gives them opportunities in UV and NIR photodetection-applications.

20.
RSC Adv ; 12(41): 26753-26762, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36320856

RESUMEN

The synthesis and characterization of aramid composites reinforced with graphene platelets are reported. Hydroxy-functionalised graphene platelets were modified with two sol-gel binders (aminopropyl- or aminophenyl-trialkoxysilanes) and then chemically linked with aramid chains. The effect of the two sol-gel binders on the physiochemical and mechanical properties was evaluated. Chemical changes during the sol-gel reaction and subsequent amidation process in the nano-composite preparation were evaluated by the XPS and FTIR analyses. Thin films of these composites with different proportions of graphene were prepared. Morphology of the hybrids prepared was studied by the SEM technique. Properties of the composite films were studied by dynamical mechanical thermal (DMT) analysis to measure their glass transition temperature (T g) and storage modulus. These properties have been compared with previously reported values using pristine graphene (Gr) as a filler. The increase in thermal mechanical properties on addition of silanized graphene (SiGr) showed a large shift in the T g and more increase in storage modulus by chemically binding SiGr sheets on the aramid chains. Aminophenyl-trialkoxysilane was found to give better results due to the presence of phenyl groups which were more rigid than propyl groups present in aminopropyl-trialkoxysilane. The effect of chemical bonding and the possible π-π secondary bond interactions between the matrix and graphene platelets on the properties of the resulting hybrids are discussed.

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