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1.
Artigo em Inglês | MEDLINE | ID: mdl-37589473

RESUMO

Turmeric is widely used as a health supplement and foodstuff in South East Asian countries because of its medicinal benefits. Like several other plants and peppers, turmeric is prone to exploitation because of its economic value, rising consumer need, and essential food element that adds colour and flavour. Due to this, quick and comprehensive testing processes are needed to detect adulterants in turmeric. In this study, pure turmeric powders were mixed with starch in proportions ranging from 0 to 50% with a 1% variation to obtain different combinations. Reflectance spectra of pure turmeric and starch mixed samples were recorded using a JASCO-V770 spectrometer from 400 to 2050 nm. The recorded spectra were pre-processed using a Multiplicative Scatter Correction (MSC) and Standard Normal Variate (SNV). The Savitzky-Golay (SG) filter was initially applied to these original (X), MSC, and SNV-corrected spectra. Secondly, the Extra Tree Regressor (ETR) feature selection method was employed to select the best features. Finally, principal component analysis (PCA) was used to reduce the dimension of the selected features. The stacked generalization method was applied to improve the performance of this work. Both regressors and classifier stacking techniques have been tested with different classification and regression methods. The K-Nearest Neighbours (KNN), Decision Tree (DT), and Random Forest (RF) models were used as base learners, and Logistic Regression (LRC) was used as a meta-model for classification and Linear Regression (LR) for regression analysis. The proposed method achieved the best regression performance with r2 of 0.999, Root Mean Square Error (RMSE) of 0.206, Ratio of Performance to Deviation (RPD) of 73.73, and Range Error Ratio (RER) of 480.58, whereas 100% F1 score and Matthew's Correlation Coefficient (MCC) classification performance.


Assuntos
Curcuma , Amido , Espectroscopia de Luz Próxima ao Infravermelho , Suplementos Nutricionais , Aromatizantes
2.
Indian J Anaesth ; 67(3): 283-289, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37250513

RESUMO

Background and Aims: Predicting complications after major oncosurgery is particularly daunting in the elderly subcategory of patients owing to factors like preexisting age-related immune cellular senescence and a significant imbalance of oxygen delivery (DO2) and consumption (VO2) characteristic of major oncological surgeries. The respiratory exchange ratio (RER) indicates DO2-VO2 balance and onset of anaerobic metabolism. We evaluated the ability of RER in predicting the occurrence of postoperative complications following geriatric oncosurgery. Materials and Methods: In the study, we enrolled 96 patients aged 65 years and above undergoing definitive surgery for gastrointestinal malignancy. The RER was calculated at predefined time points by a non-volumetric method from the respiratory parameters as RER = (end-tidal fractional carbon dioxide [FetCO2] - fraction of inspired carbon dioxide [FiCO2]/fraction of inspired oxygen [FiO2] - end-tidal fractional oxygen [FetO2]). Other indices of tissue perfusion, like central venous oxygen saturation and lactate levels, were also recorded. The patients were followed up for postsurgical complications. The predictive value of RER and other perfusion parameters was assessed and compared by appropriate statistical methods. Results: The patients who sustained major complications had a higher RER than the patients who did not sustain complications (1.47 ± 0.99 vs. 0.90 ± 0.31, P = 0.001). An intraoperative cutoff value of RER ≥0.89 was found to best predict postoperative complications at a specificity and sensitivity rate of 81.2% and 76%, respectively. End-operative partial pressure of carbon dioxide (pCO2) gap of >5.2 mm and elevated arterial lactate could also predict postsurgical complications in this age group. Conclusion: The RER can serve as a noninvasive, real-time and sensitive indicator of tissue hypoperfusion and postoperative complications in geriatric gastrointestinal oncosurgery.

3.
J Exp Zool A Ecol Integr Physiol ; 337(6): 600-611, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35286779

RESUMO

d-galactose (DG)-induced rodent aging model has widely been used for the study of age-related dysfunctions of various organs, including gonads and uterus. Antidiabetic drug metformin has gained an attention as antiaging drug in model organism and human but its effect on uterus has not been studied in relation to induced aging. Therefore, we investigated the effect of metformin on uterus of DG-induced aging mice model. Mice were randomly divided into three groups, that is, control (CN), DG-induced aging model and aging model treated with metformin. Histomorphometric results showed significantly decreased number of uterine glands, endometrial thickness, and increased luminal epithelium height in aging model. Furthermore, metformin resumed the number of uterine glands, endometrial thickness, and luminal epithelium height up to CN group. Metformin has also significantly decreased the age-associated oxidative stress (malondialdehyde and lipid hydroperoxide). Superoxide dismutase was significantly decreased in both treated groups compared to the CN group. However, catalase and glutathione peroxidase enzymes were significantly increased by metformin compared to the aging model. Immunostaining of active caspase3 and BAX were intense in the endometrium of aging model compare to CN- and metformin-treated groups. Localization of B-cell lymphoma 2 (Bcl2) showed intense immunostaining in the uterus of CN- and metformin-treated groups, with mild immunostaining in aging model. Our observations suggested that metformin treatment might be helpful for management of age-associated uterine dysfunctions. Moreover, it may be concluded that metformin might ameliorate uterine dysfunctions by reducing oxidative stress, suppressing apoptosis, and increasing the survival/antiapoptotic protein Bcl2.


Assuntos
Envelhecimento , Metformina , Estresse Oxidativo , Útero , Envelhecimento/efeitos dos fármacos , Animais , Caspase 3 , Feminino , Galactose , Metformina/farmacologia , Camundongos , Útero/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
5.
Sci Rep ; 11(1): 21296, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34716334

RESUMO

Rotating forms of suspension culture allow cells to aggregate into spheroids, prevent the de-differentiating influence of 2D culture, and, perhaps most importantly of all, provide physiologically relevant, in vivo levels of shear stress. Rotating suspension culture technology has not been widely implemented, in large part because the vessels are prohibitively expensive, labor-intensive to use, and are difficult to scale for industrial applications. Our solution addresses each of these challenges in a new vessel called a cell spinpod. These small 3.5 mL capacity vessels are constructed from injection-molded thermoplastic polymer components. They contain self-sealing axial silicone rubber ports, and fluoropolymer, breathable membranes. Here we report the two-fluid modeling of the flow and stresses in cell spinpods. Cell spinpods were used to demonstrate the effect of fluid shear stress on renal cell gene expression and cellular functions, particularly membrane and xenobiotic transporters, mitochondrial function, and myeloma light chain, cisplatin and doxorubicin, toxicity. During exposure to myeloma immunoglobulin light chains, rotation increased release of clinically validated nephrotoxicity cytokine markers in a toxin-specific pattern. Addition of cisplatin or doxorubicin nephrotoxins reversed the enhanced glucose and albumin uptake induced by fluid shear stress in rotating cell spinpod cultures. Cell spinpods are a simple, inexpensive, easily automated culture device that enhances cellular functions for in vitro studies of nephrotoxicity.


Assuntos
Técnicas de Cultura de Células/métodos , Células Epiteliais/citologia , Túbulos Renais Proximais/citologia , Linhagem Celular , Humanos , Estresse Mecânico
6.
Chem Asian J ; 16(19): 2871-2895, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34375014

RESUMO

It is well established that the excessive and uncontrolled use of fossil fuels and organic chemicals have put a risk to the earth's environment and the life that sustains within it. Carbon-free, sustainable, alternative energy technologies have therefore become the prime focus of current research. Smart inorganic materials have emerged as the potential solution to suffice energy needs and remediate the organic pollutants discharged to the environment. One such promising, versatile material is FeCo2 O4 which has gained immense research interest in the present decade due to its high efficiency and performance in energy and environmental applications. Innovative material design strategies involving the interplay of nanostructured morphology, chemical composition, redox surface states, and defect engineering have significantly enhanced both electrochemical and catalytic properties of FeCo2 O4 . Therefore, this review article aims to provide the first-ever comprehensive account of the latest research and developments in design-synthesis strategies, characterization techniques, and applications of nanostructured FeCo2 O4 and its composites in various electrochemical as well as catalytic applications. A detailed account of the nanostructured FeCo2 O4 and its composites in various energy storage and conversion devices such as supercapacitors (SCs), batteries, and fuel cells has been presented. Furthermore, a special section has been devoted to highlight the role of FeCo2 O4 in enhancing the sluggish reaction kinetics of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in water splitting application. This review also highlights the role of nanostructured FeCo2 O4 in photocatalytic waste water treatment, gas sensing, and dual-phase membrane technologies wherein FeCo2 O4 has demonstrated promising performance.

7.
Chem Soc Rev ; 50(17): 9845-9998, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34308940

RESUMO

In this review, we describe the developments in the field of naphthalene diimides (NDIs) from 2016 to the presentday. NDIs are shown to be an increasingly interesting class of molecules due to their electronic properties, large electron deficient aromatic cores and tendency to self-assemble into functional structures. Almost all NDIs possess high electron affinity, good charge carrier mobility, and excellent thermal and oxidative stability, making them promising candidates for applications in organic electronics, photovoltaic devices, and flexible displays. NDIs have also been extensively studied due to their potential real-world uses across a wide variety of applications including supramolecular chemistry, sensing, host-guest complexes for molecular switching devices, such as catenanes and rotaxanes, ion-channels, catalysis, and medicine and as non-fullerene accepters in solar cells. In recent years, NDI research with respect to supramolecular assemblies and mechanoluminescent properties has also gained considerable traction. Thus, this review will assist a wide range of readers and researchers including chemists, physicists, biologists, medicinal chemists and materials scientists in understanding the scope for development and applicability of NDI dyes in their respective fields through a discussion of the main properties of NDI derivatives and of the status of emerging applications.

8.
J Hazard Mater ; 409: 124980, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33418290

RESUMO

In recent years, substantial progress has been made towards developing effective catalysts for the hydrogenation of CO2 into fuels. However, the quest for a robust catalyst with high activity and stability still remains challenging. In this study, we present a cost-effective catalyst composed of MoS2 nanosheets and functionalized porous date seed-derived activated carbon (f-DSAC) for hydrogenation of CO2 into formic acid (FA). As-fabricated MoS2/f-DSAC catalysts were characterized by FE-SEM, XRD, Raman, FT-IR, BET, and CO2-TPD analyses. At first, bicarbonate (HCO3-) was successfully converted into FA with a high yield of 88% at 200 °C for 180 min under 10 bar H2 atmosphere. A possible reaction pathway for the conversion of HCO3- into FA is postulated. The catalyst has demonstrated high activity and long-term stability over five consecutive cycles. Additionally, MoS2/f-DSAC catalyst was effectively used for the conversion of gaseous CO2 into FA at 200 °C under 20 bar (CO2/H2 = 1:1) over 15 h. The catalyst exhibited a remarkable TOF of 510 h-1 with very low activation energy of 12 kJ mol-1, thus enhancing the catalytic conversion rate of CO2 into FA. Thus, this work demonstrates the MoS2/f-DSAC nanohybrid system as an efficient non-noble catalyst for converting CO2 into fuels.

9.
ACS Appl Mater Interfaces ; 13(1): 1288-1300, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356091

RESUMO

Double helical DNA structure is one of the most beautiful and fascinating nanoarchitecture nature has produced. Mimicking nature's design by the tailored synthesis of semiconductor nanomaterials such as WO3 into a DNA-like double helical superstructure could impart special properties, such as enhanced stability, electrical conductivity, information storage, signal processing, and catalysis, owing to the synergistic interaction across helices. However, double helical WO3 synthesis is extremely challenging and has never been reported earlier. This investigation presents the first-ever report on a facile synthesis route for designing a DNA-like double helical WO3-x/C microfiber superstructure via self-assembly of in situ carbon fiber-encapsulated WO3-x nanorods. This innovative design strategy is completely template-free and does not require predesigned helical templates or hydro/solvothermal treatment. Detailed spectroscopic material characterization and electrochemical studies confirmed that the double helical structure with carbon fiber-WO3-x heterostructures enabled effective induction and distribution of oxygen vacancies along with W5+/W6+ redox surface states. Furthermore, faster electrode-electrolyte interfacial kinetics, improved electrical conductivity, and cycling stability has been observed in the carbon fiber-WO3-x heterostructures which resulted in a high area specific capacitance of 401 mF cm-2 at 2 mA cm-2 with excellent capacitance retention of >94% for more than 5000 cycles. Additionally, the carbon fiber-WO3-x heterostructures demonstrated promising performance when fabricated in a solid-state asymmetric supercapacitor device with the power density of 498 W kg-1 at an energy density of 15.4 W h kg-1. Therefore, the rare DNA-like double helical WO3-x/C superstructure synthesized in this study could open new doorways toward in situ, facile fabrication of double helical superstructures for energy and environmental applications.

10.
Int J Biol Macromol ; 167: 1248-1261, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33189751

RESUMO

Graphene oxide (GO) crosslinked nanocomposites hydrogels (NCH) of chitosan (CS) and carboxymethyl cellulose (CMC) were synthesized and the feasibility of its application as a versatile adsorbent for the remediation of cationic (methylene blue, MB) as well as anionic (methyl orange, MO) dyes contaminated wastewater was explored. Initially, GO was functionalized with vinyltriethoxysilane which was subsequently used as a chemical crosslinker to synthesize the NCH of CS and CMC (CS/CMC-NCH) with the polymeric mixture of diallyldimethylammonium chloride and 2-acrylamido-2-methyl-1-propanesulfonic acid. About 99% dye was adsorbed from 50 mg/L dye solution of MB dye with 0.4 g/L of CS/CMC-NCH at pH 7, whereas, for MO about 82% dye was adsorbed with 0.6 g/L of CS/CMC-NCH at pH 3. The Adsorption of both dyes is well explained using pseudo-second-order and Langmuir models with the maximum adsorption capacities of 655.98 mgdye/gads for MB and 404.52 mgdye/gads for MO. Thermodynamics studies suggested spontaneous and exothermic nature of the adsorption process with values of ΔS < 0 and ΔH > 0. Furthermore, CS/CMC-NCH showed excellent regeneration capacity for continuous twenty cycles of adsorption-desorption. Therefore, the synthesized CS/CMC-NCH is a versatile adsorbent that can treat both anionic and cationic dyes contaminated wastewater.


Assuntos
Carboximetilcelulose Sódica/química , Quitosana/química , Corantes/química , Grafite/química , Nanogéis/química , Purificação da Água/métodos , Acrilamidas/síntese química , Acrilamidas/química , Adsorção , Alcanossulfonatos/síntese química , Alcanossulfonatos/química , Compostos Alílicos/síntese química , Compostos Alílicos/química , Ânions/química , Compostos Azo/química , Cátions/química , Corantes/análise , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno/química , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/química , Silanos/química , Termodinâmica , Águas Residuárias/análise , Poluentes Químicos da Água/análise
11.
J Environ Manage ; 258: 110029, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929065

RESUMO

The low surface area of TiO2 (50 m2g-1 - Degussa P25) due to randomly oriented, agglomerated nanostructures and charge carrier recombination tendency, has till date been its major limitation for photocatalytic remediation of polluted wastewater. This study presents an innovative process to design super porous TiO2 nanostructures with high effective surface area (238 m2g-1), robust, structurally ordered mesoporosity via a simple sol-gel assisted reflux method. Detailed material characterization studies suggest that the higher degree of intermolecular ligation in novel templates such as butanetetracarboxylic or tricarballylic acid modified titanium hydroxide gels resulted in retainment of the porous structure during the urea assisted combustion synthesis. The induction of robust structural porosity is accompanied by a reduction in pore size distribution, an increase in pore volume leading to significantly higher total surface area of the synthesized TiO2. Detailed investigation of dye adsorption kinetics and photocatalytic degradation kinetics, complemented by kinetic modeling analysis confirmed that the super porous TiO2 with robust mesoporous structure outperforms the rest of synthesized TiO2 catalyst (having only agglomerate porosity) in terms of its superior adsorption capacity, faster diffusion kinetics and photocatalytic activity for degradation of Amaranth dye. Thus, the super porous TiO2 shows promising potential for application in sustainable photocatalytic technology for remediation of wastewater contaminated with azo dyes.


Assuntos
Compostos Azo , Águas Residuárias , Adsorção , Catálise , Porosidade , Titânio
12.
Molecules ; 24(22)2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31752075

RESUMO

The fabrication of controlled supramolecular nanostructures via self-assembly of protoporphyrin IX (PPIX) was studied with enantiomerically pure l-arginine and d-arginine, and we have shown that stoichiometry controlled the morphology formed. The nanostructure morphology was mainly influenced by the delicate balance of π-π stacking interactions between PPIX cores, as well as H-bonding between the deprotonated acidic head group of PPIX with the guanidine head group of arginine. PPIX self-assembled with l-/d-arginine to create rose-like nanoflower structures for four equivalents of arginine that were 5-10 µm in length and 1-4 µm diameter. We employed UV-vis, fluorescence spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FT-IR) techniques to characterize the resulting self-assembled nanostructures. Furthermore, we investigated the catalytic activity of PPIX and arginine co-assembled materials. The fabricated PPIX-arginine nanostructure showed high enhancement of photocatalytic activity through degradation of rhodamine B (RhB) with a decrease in dye concentration of around 78-80% under simulated visible radiation.


Assuntos
Arginina/química , Nanopartículas/química , Protoporfirinas/química , Catálise , Luz , Água
13.
Photochem Photobiol Sci ; 16(7): 1126-1138, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28548665

RESUMO

The photocatalytic degradation mechanism of Amaranth, a recalcitrant carcinogenic azo dye, was investigated using mesoporous anatase TiO2 under sunlight. Mesoporous anatase TiO2 of a high photocatalytic activity has been synthesized using a sol-gel method and its photocatalytic activity for the degradation of Amaranth dye has been evaluated with respect to Degussa P25. The effect of bi-dentate complexing agents like oxalic acid, ethylene glycol and urea on the surface properties of TiO2 catalyst has been investigated using TG-DTA, FTIR, HR-TEM, SAED, PXRD, EDS, UV-DRS, PL, BET N2 adsorption-desorption isotherm studies and BJH analysis. The influence of catalyst properties such as the mesoporous network, pore volume and surface area on the kinetics of degradation of Amaranth as a function of irradiation time under natural sunlight has been monitored using UV-Vis spectroscopy. The highest rate constant value of 0.069 min-1 was obtained for the photocatalytic degradation of Amaranth using TiO2 synthesized via a urea assisted sol-gel synthesis method. The effect of the reaction conditions such as pH, TiO2 concentration and Amaranth concentration on the photodegradation rate has been investigated. The enhanced photocatalytic activity of synthesized TiO2 in comparison with P25 is attributed to the mesoporous nature of the catalyst leading to increased pore diameter, pore volume, surface area and enhanced charge carrier separation efficiency. New intermediates of photocatalytic degradation of Amaranth, namely, sodium-3-hydroxynaphthalene-2,7-disulphonate, 3-hydroxynaphthalene, sodium-4-aminonaphthalenesulphonate and sodium-4-aminobenzenesulphonate have been identified using LC-ESI-MS for the very first time, providing direct evidence for simultaneous bond cleavage pathways (-C-N-) and (-N[double bond, length as m-dash]N-). A new plausible mechanism of TiO2 catalysed photodegradation of Amaranth along with the comparison of its toxicity to that of its degradation intermediates and products is proposed.

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