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1.
Molecules ; 25(17)2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32839395

RESUMEN

The thermal conductivities of selected deep eutectic solvents (DESs) were determined using the modified transient plane source (MTPS) method over the temperature range from 295 K to 363 K at atmospheric pressure. The results were found to range from 0.198 W·m-1·K-1 to 0.250 W·m-1·K-1. Various empirical and thermodynamic correlations present in literature, including the group contribution method and mixing correlations, were used to model the thermal conductivities of these DES at different temperatures. The predictions of these correlations were compared and consolidated with the reported experimental values. In addition, the thermal conductivities of DES mixtures with water over a wide range of compositions at 298 K and atmospheric pressure were measured. The standard uncertainty in thermal conductivity was estimated to be less than ± 0.001 W·m-1·K-1 and ± 0.05 K in temperature. The results indicated that DES have significant potential for use as heat transfer fluids.


Asunto(s)
Colina/química , Agua/química
2.
Braz Dent J ; 35: 5798, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39045988

RESUMEN

Resorbed alveolar ridges, particularly in the lower jaw, have a small denture supporting area, which may cause the stress distribution of mastication load to exceed the pressure-pain threshold (PPT) and induce pain in the mucosa or potentially worsen the ridge resorption. Thus, choosing the ideal occlusal scheme among bilateral balanced (BBO), lingualized (LO), and monoplane (MO) for such conditions becomes crucial. The experiment was conducted using the finite element method on a modeling of a resorbed alveolar ridge in the lower jaw with three dentures placed on top, each of which was given different loading points according to the tooth arrangement of BBO, LO, and MO. The axial load was 100 N, and the resultant oblique loads on BBO and LO were 119 N and 106 N, respectively. The von Mises stresses for BBO, LO, and MO were observed in nine denture-supporting areas, and the results showed that the axial load did not produce stresses that exceeded the PPT value (0.64925 MPa) for BBO, LO, and MO with the highest value on area H, 0.43229 MPa, 0.39715 MPa, and 0.31576 MPa, respectively. However, the oblique load direction showed that the BBO had more areas (area E 0.80778 MPa and area H 0.76256 MPa) that exceeded the PPT than LO (area E 0.64394 MPa). The lingualized occlusal scheme is ideal for patients with resorbed alveolar ridge conditions, especially in terms of limiting interferences when the denture is functioning while maintaining comfort but still providing good masticatory performance and satisfactory esthetics.


Asunto(s)
Análisis de Elementos Finitos , Humanos , Proceso Alveolar , Análisis del Estrés Dental , Pérdida de Hueso Alveolar , Oclusión Dental , Mandíbula , Masticación/fisiología
3.
Glob Cardiol Sci Pract ; 2024(2): e202413, 2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38746065

RESUMEN

Right ventricular thrombus is a rare finding found in 4% of people diagnosed with pulmonary embolism. Although right ventricular thrombi are usually associated with atrial fibrillation, deep venous vein thrombi, or intracardiac procedures, isolated right ventricular thrombi are rare. Right ventricular thrombus has also been reported in patients with right ventricular infarction, as hypokinesis of the right ventricle causes blood stasis and promotes thrombosis as per Virchow's triad. However, we present a case of isolated RV thrombus in a patient without evidence of deep vein thrombosis or right ventricular hypokinesis who presented with dyspnea on exertion.

4.
J Stomatol Oral Maxillofac Surg ; : 101999, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39089510

RESUMEN

BACKGROUND: Medication-related osteonecrosis of the jaw (MRONJ) is a severe complication associated with prolonged bisphosphonate therapy. Increasing evidence shows that mucosal damage plays an important role in the pathogenesis of MRONJ. This study investigates the combinatorial effects of hydroxyapatite with Tualang honey on cell viability and wound healing in MRONJ. MATERIALS AND METHODS: The incorporation of Tualang honey into hydroxyapatite was assessed using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and field emission scanning electron-energy dispersive X-ray analysis microscopy (FESEM-EDX). The effect of hydroxyapatite combined with Tualang honey on cell viability was determined by WST-1 assay and wound healing was assessed by scratch assay. RESULTS: The incorporation of Tualang honey into hydroxyapatite altered the functional groups, structure, size, morphology, and components of the crystal as evidenced by FTIR, XRD and FESEM-EDX analysis. High concentrations of pamidronic acid inhibit oral fibroblast viability and wound healing. Low and high concentrations of hydroxyapatite demonstrate non-toxicity towards fibroblast cells. Furthermore, hydroxyapatite reversed the action of pamidronic acid on the cells; it increased fibroblast viability but did not close the wound. Tualang honey promotes fibroblast viability and wound closure. However, the addition of Tualang honey is unable to overcome the inhibitory effects of pamidronic acid on fibroblasts. The addition of Tualang honey and hydroxyapatite improved the cell viability and accelerated wound closure of fibroblast exposed to pamidronic acid. CONCLUSION: These findings demonstrated that the combination treatment protects oral fibroblasts by preventing bisphosphonate toxicity.

5.
Cureus ; 15(1): e34112, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36843826

RESUMEN

Typically, right heart failure (RHF) may occur following left heart failure (LHF) in chronic volume overload states such as chronic severe mitral regurgitation (MR) through chronically elevated pulmonary pressures. In Lutembacher syndrome (LS), the direct shunting through a secundum type atrial septal defect (ASD) results in congestive heart failure in the setting of severe mitral stenosis (MS) with or without elevated pulmonary arterial or venous pressures. We report a rare case of severe isolated RHF and bi-atrial enlargement resulting from the direct shunting through a secundum type ASD in the presence of a severe eccentric primary MR. There are no significant cases documented like this after a thorough search using PubMed, Medline, and Google Scholar. A review of the literature suggests that LS is also caused by a combination of mitral regurgitation and a secundum-type atrial septal defect without mitral stenosis, though rarely. Because this is a primary MR, we feel it is a case of LS with MR, ruling out a combination of secondary MR and secundum-type atrial septal defect.

6.
Pharmaceutics ; 15(3)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36986729

RESUMEN

The new era of nanomedicine offers significant opportunities for cancer diagnostics and treatment. Magnetic nanoplatforms could be highly effective tools for cancer diagnosis and treatment in the future. Due to their tunable morphologies and superior properties, multifunctional magnetic nanomaterials and their hybrid nanostructures can be designed as specific carriers of drugs, imaging agents, and magnetic theranostics. Multifunctional magnetic nanostructures are promising theranostic agents due to their ability to diagnose and combine therapies. This review provides a comprehensive overview of the development of advanced multifunctional magnetic nanostructures combining magnetic and optical properties, providing photoresponsive magnetic platforms for promising medical applications. Moreover, this review discusses various innovative developments using multifunctional magnetic nanostructures, including drug delivery, cancer treatment, tumor-specific ligands that deliver chemotherapeutics or hormonal agents, magnetic resonance imaging, and tissue engineering. Additionally, artificial intelligence (AI) can be used to optimize material properties in cancer diagnosis and treatment, based on predicted interactions with drugs, cell membranes, vasculature, biological fluid, and the immune system to enhance the effectiveness of therapeutic agents. Furthermore, this review provides an overview of AI approaches used to assess the practical utility of multifunctional magnetic nanostructures for cancer diagnosis and treatment. Finally, the review presents the current knowledge and perspectives on hybrid magnetic systems as cancer treatment tools with AI models.

7.
Chemosphere ; 299: 134439, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35351477

RESUMEN

Dual-functional photo (electro)catalysis (PEC) is a key strategy for removing coexisting heavy metals and phenolic compounds from wastewater treatment systems. To design a PEC cell, it is crucial to use chemically stable and cost-effective bifunctional photocatalysts. The present study shows that ruthenium metallic nanoparticles decorated with CoFe2O4/RGO (Ru-CoFe2O4/RGO) are effective bifunctional photoelectrodes for the reduction of Cr(VI) ions. Ru-CoFe2O4/RGO achieves a maximum Cr(VI) reduction rate of 99% at 30 min under visible light irradiation, which is much higher than previously reported catalysts. Moreover, PEC Cr(VI) reduction rate is also tuned by adding varying concentration of phenol. A mechanism for the concurrent removal of Cr(VI) and phenol has been revealed over a bifunctional Ru-CoFe2O4/RGO catalyst. A number of key conclusions emerged from this study, demonstrating the dual role of phenol during Cr(VI) reduction by PEC. Anodic oxidation of phenol produces the enormous H+ ion, which appears to be a key component of Cr(VI) reduction. Additionally, phenolic molecules serve as hole (h+) scavengers that reduce e-/h+ recombination, thus enhancing the reduction rate of Cr(VI). Therefore, the Ru-CoFe2O4/RGO photoelectrode exhibits a promising capability of reducing both heavy metals and phenolic compounds simultaneously in wastewater.


Asunto(s)
Nanopartículas del Metal , Fenoles , Catálisis , Cromo/química , Grafito , Oxidación-Reducción , Fenol
8.
Sci Total Environ ; 790: 148081, 2021 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-34091328

RESUMEN

There exist several well-known methods with varying maturity for capturing carbon dioxide from emission sources of different concentrations, including absorption, adsorption, cryogenics and membrane separation, among others. The capture and separation steps can produce almost pure CO2, but at substantial cost for being conditioned for transport and final utilization, with high economical risks to be considered. A possible way for the elimination of this conditioning and cost is direct CO2 utilization, whether on-site in a further process but within the same plant, or in-situ, coupling both capture and conversion in the same unit. This approach is usually called integrated carbon capture and utilization (ICCU) or integrated carbon capture and conversion (ICCC), and has lately started receiving considerable attention in many circles. As CO2 is already industrially employed in other sectors, such as food preservation, water treatment and conversion to high added-value chemicals and fuels such as methanol, methane, etc., among others, it is of great interest to explore the global ICCC approach. Catalytic-based processes play a key role in CO2 conversion, and different technologies are gaining great attention from both academia and industry. However, the 'big picture of ICCU' and in which technology the efforts should focus on at large scale is still unclear. This review analyzes some promising concepts of ICCU specifically on CO2 catalytic conversion, highlighting their current commercial relevance as well as challenges that have to be faced today and in the next future.


Asunto(s)
Dióxido de Carbono , Metano , Catálisis , Industrias , Metanol
9.
Environ Sci Pollut Res Int ; 28(24): 31803-31813, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33611732

RESUMEN

Cut flowers and floral waste (CFW) is a major concern in the present era. This study emphasizes the reuse of cut flowers as a neat bioadsorbent and activated carbon (AC). The biomass from the cut flowers was utilized as a neat bioadsorbent for the removal of the antibiotic levofloxacin and lead ions from water. The results revealed that the neat bioadsorbent was able to remove 60% levofloxacin and 45% of lead ions. Upon chemical activation of the CFW (using KOH), almost all levofloxacin and more than 99% of lead ions were removed. Physical activation (using CO2) gave a material that removed 90% of levofloxacin and 85% of lead ions. The adsorption of levofloxacin and lead ions on all the adsorbents followed Langmuir isotherms and pseudo-second-order kinetic model. The results have been further explained via the prediction of interaction energies between the adsorbates and adsorbents using COSMO-RS simulation.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Flores/química , Concentración de Iones de Hidrógeno , Cinética , Tecnología , Aguas Residuales , Contaminantes Químicos del Agua/análisis
10.
Sci Rep ; 10(1): 15943, 2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-32994515

RESUMEN

A novel triazene-anthracene-based fluorescent aminal linked porous organic polymer (TALPOP) was prepared via metal free-Schiff base polycondensation reaction of 9,10-bis-(4,6-diamino-S-triazin-2-yl)anthracene and 2-furaldehyde. The polymer has exceptional chemical and thermal stabilities and exhibit good porosity with Brunauer-Emmett-Teller surface area of 401 m2g-1. The combination of such porosity along with the highly conjugated heteroatom-rich framework enabled the polymer to exhibit exceptional iodine vapor uptake of up to 314 wt % and reversible iodine adsorption in solution. Because of the inclusion of the anthracene moieties, the TALPOP exhibited excellent detection sensitivity towards iodine via florescence quenching with Ksv value of 2.9 × 103 L mol-1. The cost effective TALPOP along with its high uptake and sensing of iodine, make it an ideal material for environmental remediation.

11.
Environ Technol ; 40(25): 3337-3350, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29718787

RESUMEN

Multiwalled carbon nanotubes and their magnetite derivatives were employed as adsorbents for emulsified oil removal from produced water. The experimental parameters for maximum emulsified oil removal efficiency and effective regeneration of these adsorbents were determined. The optimum parameters in terms of adsorbent dosage, contact time, salinity, pH and temperature were 3.0 g/L, 20.0 min, 0 ppm, 7.0 and 25°C for both adsorbents. Due to their low density, multiwalledcarbon nanotubes could not be successfully employed in packed bed columns. The magnetite derivative has a larger density and hence, for the removal of emulsified oil from produced water packed bed column studies were performed utilizing multiwalled carbon magnetite nanotubes. The packed bed column efficiency and behaviour were evaluated using Thomas, Clark, Yan et al. and Bohart and Adams models. The Yan model was found to best describe the column experimental data. The adsorbents were regenerated using n-hexane and reused several times for oil removal from produced water without any significant decrease in their initial adsorption capacities.


Asunto(s)
Nanotubos de Carbono , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Óxido Ferrosoférrico , Agua
12.
Braz. dent. j ; Braz. dent. j;35: e24, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, BBO - odontología (Brasil) | ID: biblio-1564079

RESUMEN

Abstract Resorbed alveolar ridges, particularly in the lower jaw, have a small denture supporting area, which may cause the stress distribution of mastication load to exceed the pressure-pain threshold (PPT) and induce pain in the mucosa or potentially worsen the ridge resorption. Thus, choosing the ideal occlusal scheme among bilateral balanced (BBO), lingualized (LO), and monoplane (MO) for such conditions becomes crucial. The experiment was conducted using the finite element method on a modeling of a resorbed alveolar ridge in the lower jaw with three dentures placed on top, each of which was given different loading points according to the tooth arrangement of BBO, LO, and MO. The axial load was 100 N, and the resultant oblique loads on BBO and LO were 119 N and 106 N, respectively. The von Mises stresses for BBO, LO, and MO were observed in nine denture-supporting areas, and the results showed that the axial load did not produce stresses that exceeded the PPT value (0.64925 MPa) for BBO, LO, and MO with the highest value on area H, 0.43229 MPa, 0.39715 MPa, and 0.31576 MPa, respectively. However, the oblique load direction showed that the BBO had more areas (area E 0.80778 MPa and area H 0.76256 MPa) that exceeded the PPT than LO (area E 0.64394 MPa). The lingualized occlusal scheme is ideal for patients with resorbed alveolar ridge conditions, especially in terms of limiting interferences when the denture is functioning while maintaining comfort but still providing good masticatory performance and satisfactory esthetics.


Resumo Os rebordos alveolares reabsorvidos, especialmente na mandíbula inferior, têm uma pequena área de suporte para prótese, o que pode fazer com que a distribuição de estresse da carga mastigatória exceda o limiar de pressão-dor (PPT) e induza dor na mucosa ou piore potencialmente a reabsorção do rebordo. Assim, a escolha do esquema oclusal ideal entre balanceado bilateral (BBO), lingualizado (LO) e monoplano (MO) para essas condições torna-se crucial. O experimento foi conduzido usando o método de elementos finitos em um modelo de um rebordo alveolar reabsorvido na mandíbula inferior com três dentaduras colocadas na parte superior, cada uma das quais recebeu diferentes pontos de carga de acordo com o arranjo dentário de BBO, LO e MO. A carga axial foi de 100 N, e as cargas oblíquas resultantes em BBO e LO foram de 119 N e 106 N, respectivamente. As tensões de von Mises para BBO, LO e MO foram observadas em nove áreas de suporte da dentadura, e os resultados mostraram que a carga axial não produziu tensões que excedessem o valor PPT (0,64925 MPa) para BBO, LO e MO com o valor mais alto na área H, 0,43229 MPa, 0,39715 MPa e 0,31576 MPa, respectivamente. Entretanto, a direção da carga oblíqua mostrou que o BBO tinha mais áreas (área E 0,80778 MPa e área H 0,76256 MPa) que excediam a PPT do que o LO (área E 0,64394 MPa). O esquema oclusal lingualizado é ideal para pacientes com condições de rebordo alveolar reabsorvido, especialmente em termos de limitação de interferências quando a dentadura está funcionando, mantendo o conforto, mas ainda proporcionando um bom desempenho mastigatório e uma estética satisfatória.

13.
Colloids Surf B Biointerfaces ; 63(1): 116-21, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18215510

RESUMEN

A new sorbent potato peels, which are normally discarded as solid waste for removing toxic metal ion Cu(II) from water/industrial waste water have been studied. Potato peels charcoal (PPC) was investigated as an adsorbent of Cu(II) from aqueous solutions. Kinetic and isotherm studies were carried out by studying the effects of various parameters such as temperature, pH and solid liquid ratios. The optimum pH value for Cu(II) adsorption onto potato peels charcoal (PPC) was found to be 6.0. The thermodynamic parameters such as standard Gibb's free energy (Delta G degrees ), standard enthalpy (Delta H degrees ) and standard entropy (DeltaS degrees ) were evaluated by applying the Van't Hoff equation. The thermodynamics of Cu(II) adsorption onto PPC indicates its spontaneous and exothermic nature. The equilibrium data at different temperatures were analyzed by Langmuir and Freundlich isotherms.


Asunto(s)
Cobre/aislamiento & purificación , Residuos Industriales/análisis , Eliminación de Residuos , Aguas del Alcantarillado/análisis , Solanum tuberosum/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Temperatura , Termodinámica
14.
Environ Sci Pollut Res Int ; 25(17): 17033-17037, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29633191

RESUMEN

Red cotton bug, Dysdercus koenigii (Hemiptera: Pyrrhocoridae), has become the major insect pest of various crops, including cotton, and thereby reducing the yield qualitatively and quantitatively and synthetic insecticides belonging to different groups are the major control agents for such insect pests. A laboratory experiment was carried out to evaluate the effect of different conventional insecticides, i.e., imidacloprid, deltamethrin, lambda cyhalothrin, gamma cyhalothrin and cyfluthirn on haemocytes of D. koenigii. The individuals were exposed to insecticides separately and data was recorded after 30 and 60 min of the exposure. The findings of current study depicted chlorpyrifos to be more effective and significant alterations in total haemocyte counts and differential haemocyte counts were observed in the cyfluthirn treated D. koenigii. In addition to this, cell structure was also disrupted as an immune response. Similar studies would also be helpful to understand the defence mechanisms of insects against the xenobiotics which will help to device efficient management tools for D. koenigii.


Asunto(s)
Cloropirifos/farmacología , Hemípteros/efectos de los fármacos , Heterópteros/efectos de los fármacos , Insecticidas/farmacología , Neonicotinoides/química , Nitrilos/química , Nitrocompuestos/química , Piretrinas/química , Animales
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