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1.
PLOS Glob Public Health ; 4(5): e0001865, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38722987

RESUMEN

Every clinical laboratory should ideally establish its own population-specific reference intervals (RIs) to promote precision and evidence-based medicine. However, clinical laboratories in Nepal find it easier to follow external RIs than establish their own, leading to a lack of RIs specific to the local population. This study thus aimed to establish RIs of routine LFTs for the adult population of Gandaki Province, Nepal, and compare them with the current RIs used by our laboratory. We established the dry-chemistry-based reference intervals of 11 common LFT parameters for the adult population of Gandaki Province, Nepal using the direct priori-based method. The combined and sex-specific 95% double-sided RIs of total protein, albumin, globulin, A/G ratio, bilirubin, aspartate aminotransaminase (AST), alanine aminotransaminase (ALT), AST/ALT ratio, and alkaline phosphatase (ALP) were established using non-parametric percentile method. The new RIs were also compared with the currently used RIs that were adopted from the reagent kit inserts. The newly established RIs for each LFT were: Total proteins: 68.0-69.0g/L, albumin: 39.0-52.0g/L; globulin: 27.0-42.0g/L; A/G ratio: 1.1-1.8; total bilirubin: 5.13-25.65µmol/L (0.30-1.50mg/dl); unconjugated bilirubin: 1.71-17.10µmol/L (0.10-1.00mg/dl); conjugated bilirubin: 0.00-10.26 µmol/L (0.00-0.60mg/dl); AST: 20.0-43.2U/L; ALT: 11.0-53.0 U/L; AST/ALT ratio: 0.7-2.1; ALP: 42.0-135.4U/L. The RIs of albumin, globulin, A/G ratio, AST, ALT, and AST/ALT ratio differed significantly (p < 0.05) between males and females. Moreover, calculated out-of-range values showed that up to 4-40% of apparently healthy adults were classified as having abnormal test results based on current RIs. The newly established RIs fulfil the need for population and platform-specific RIs for the adult population of Gandaki Province of Nepal and bring more conformity and accuracy in interpreting the LFT results, diagnosis of hepatobiliary diseases, clinical decision-making, monitoring the success of therapy and future liver specific biomedical researches within the Gandaki Province of Nepal.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38669304

RESUMEN

Zinc-ion batteries (ZIBs) are promising candidates for safe energy storage applications. However, undesirable parasitic reactions such as dendrite growth, gas evaluation, anode corrosion, and structural damage to the cathode under an acidic microenvironment severely affected cell performance. To resolve these issues, an MXene entrapped in an ionic liquid semi-solid gel polymer electrolyte (GPE) composite was explored. The molecular-level mixing of poly(vinylidene fluoride-co-hexafluoropropylene) (PVHF), zinc trifluoromethanesulfonate (Zn(OTF)2), 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF4) ionic liquid, and Ti3C2Tx MXene provided a controlled Zn2+ shuttle toward the anode/cathode. Ti3C2Tx/EMIBF4/Zn(OTF)2/PVHF exhibited a breaking strength of 0.36 MPa with an associated extension of 23%. The Zn//Ti3C2Tx/EMIBF4/Zn(OTF)2/PVHF//Zn symmetric cell with continuous zinc plating/stripping exhibited excellent Zn2+ ion mobility toward the anode and cathode without undesired reactions. This was confirmed by post-mortem analysis after a symmetric cell compatibility test. The as-prepared GPE with a Na3V2(PO4)3 (NVP) cathode exhibited a high chemical diffusion coefficient of 1.14 × 10-7. It also showed an outstanding reversible capacity of 89 mAh g-1 at C/10 with an average discharge plateau voltage of 1.45 V, cycle durability, and controlled self-discharge. These results suggested that the Zn2+ ions in the Ti3C2Tx/EMIBF4/Zn(OTF)2/PVHF composite are reversibly labile in the anode and cathode directions.

3.
ACS Appl Mater Interfaces ; 15(9): 11927-11939, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36890694

RESUMEN

The exploration of heterostructure materials with unique electronic properties is considered a desirable platform for fabricating electrode/surface interface relationships for constructing asymmetric supercapacitors (ASCs) with high energy density. In this work, a heterostructure based on amorphous nickel boride (NiXB) and crystalline square bar-like manganese molybdate (MnMoO4) was prepared by a simple synthesis strategy. The formation of the NiXB/MnMoO4 hybrid was confirmed by powder X-ray diffraction (p-XRD), field emission scanning electron microscopy (FE-SEM), field-emission transmission electron microscopy (FE-TEM), Brunauer-Emmett-Teller (BET), Raman, and X-ray photoelectron spectroscopy (XPS). In this hybrid system (NiXB/MnMoO4), the intact combination of NiXB and MnMoO4 leads to a large surface area with open porous channels and abundant crystalline/amorphous interfaces with a tunable electronic structure. This NiXB/MnMoO4 hybrid shows high specific capacitance (587.4 F g-1) at 1 A g-1, and it even retains a capacitance of 442.2 F g-1 at 10 A g-1, indicating superior electrochemical performance. The fabricated NiXB/MnMoO4 hybrid electrode also exhibited an excellent capacity retention of 124.4% (10000 cycles) and a Coulombic efficiency of 99.8% at a current density of 10 A g-1. In addition, the ASC device (NiXB/MnMoO4//activated carbon) achieved a specific capacitance of 104 F g-1 at 1 A g-1 and delivered a high energy density of 32.5 Wh.kg-1 with a power density of 750 W·kg-1. This exceptional electrochemical behavior is due to the ordered porous architecture and the strong synergistic effect of NiXB and MnMoO4, which enhances the accessibility and adsorption of OH- ions that improve electron transport. Moreover, the NiXB/MnMoO4//AC device exhibits excellent cyclic stability with a retention of 83.4% of the original capacitance after 10000 cycles, which is due to the heterojunction layer between NiXB and MnMoO4 that can improve the surface wettability without causing structural changes. Our results show that the metal boride/molybdate-based heterostructure is a new category of high-performance and promising material for the growth of advanced energy storage devices.

4.
Nanomaterials (Basel) ; 13(4)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36839056

RESUMEN

Metal sulfides (MS) and mixed metal sulfides (MTMS) have been considered potential candidates over their metal oxide/mixed metal oxide counterparts in recent years. Herein, one MTMS, i.e., NiCo2S4, was combined with 2D MS MoS2 through a single-step solvothermal process with different morphologies (sheet-like and rod-like) for supercapacitor applications. The resulting electrode exhibited excellent coulombic efficiency, high specific capacitance, superior energy density, and, most importantly, ultra-high cycling stability. In particular, the electrode delivered a capacitance of 2594 F g-1 at 0.8 A g-1 after 45,000 charge/discharge cycles with a remarkable stability of 192%. Moreover, the corresponding hybrid supercapacitor device displayed an impressive coulombic efficiency of 123% after 20,000 cycles and 118% after 45,000 cycles. In addition, the device also exhibited a decent energy density of 31.9 Wh kg-1 and good cycling stability of 102% over 15,000 cycles.

5.
Nanomaterials (Basel) ; 12(21)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36364589

RESUMEN

Transition metal oxide aerogels are a fascinating class of compounds that have received considerable attention in the last decade owing to their unique and exceptional properties, including high porosity, large surface area, and ultralow density. In this study, α-Ni(OH)2 aerogels and annealed NiO/Ni aerogels were used to design and fabricate a two-electrode supercapacitor device. The physicochemical properties of the as-synthesized aerogels were characterized through X-ray diffraction, scanning electron microscopy, transmission electron microscopy, the Brunauer-Emmett-Teller theory, and X-ray photoelectron spectroscopy studies. The annealed NiO/Ni aerogels showed a (specific capacitance of 1060 F/g) specific capacity of 422 C/g at 1 A/g current density and with good cycling stability (up to 10,000 cycles). The supercapacitor also demonstrated an energy density of 32.4 Wh/kg and power density of 1800 W/kg at a current density of 2 A/g. The specific capacitance of NiO/Ni aerogels was more than twice that of the α-Ni(OH)2 aerogels. The practical applications of the aerogel were demonstrated by fabricating a two-electrode device.

6.
Nanomaterials (Basel) ; 12(11)2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35683798

RESUMEN

To overcome the issues related to supercapacitor (SC) electrodes, such as high cost, low specific capacitance (Cs), low energy density (ED), requirements for expensive binder, etc., binderless electrodes are highly desirable. Here, a new ternary nanohybrid is presented as a binder-free SC electrode based on Ni3S2, CoMoS4, and MnO2. A facile two-step hydrothermal route, followed by a short thermal annealing process, is developed to grow amorphous polyhedral structured CoMoS4 and further wrap MnO2 nanowires on Ni foam. This rationally designed binder-free electrode exhibited the highest Cs of 2021 F g-1 (specific capacity of 883.8 C g-1 or 245.5 mAh g-1) at a current density of 1 A g-1 in 1 M KOH electrolyte with a highly porous surface morphology. This electrode material exhibited excellent cycling stability (90% capacitance retention after 4000 cycles) due to the synergistic contribution of individual components and advanced surface properties. Furthermore, an aqueous binder-free asymmetric SC based on this ternary composite exhibited an ED of 20.7 Wh kg-1, whereas a solid-state asymmetric SC achieved an ED of 13.8 Wh kg-1. This nanohybrid can be considered a promising binder-free electrode for both aqueous and solid-state asymmetric SCs with these remarkable electrochemical properties.

7.
J Colloid Interface Sci ; 624: 494-504, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35667211

RESUMEN

Transition metal sulfide-based electrode materials are promising candidates for energy storage applications owing to their richer redox-active sites and higher electrical conductivity than their oxide counterparts. Manganese-cobalt-sulfide (MCS) nanoflakes were synthesized on nickel foam in the presence of polyvinylpyrrolidone (PVP) as a capping agent using a one-step hydrothermal method. The variation in the amount of PVP in the reaction solution had a prominent impact on the MCS electrode morphology. PVP altered the morphology of the MCS nanoflakes. Different shapes of interconnecting-nanoflake arrays were formed with different amounts of PVP. The MCS electrode prepared using 0.2 g of PVP (MCS-P2) showed the best efficiency with a specific capacity of 1312 C g-1 (3215 F g-1) at 1 A g-1 and still retained a remarkable capacity of 1000 C g-1 (2480 F g-1) at 20 A g-1. Moreover, the hybrid supercapacitor (HS) device consisting of MCS-P2//reduced graphene oxide (rGO) revealed a high energy density of 48.7 Wh kg-1 at a corresponding power density of 386 W kg-1. Even at a higher power density of 10.8 kW kg-1, a notable energy density of 25.5 Wh kg-1 was retained. These remarkable results highlight the potential applications of the MCS-P2 electrode material in energy storage.

8.
Crit Rev Food Sci Nutr ; 62(20): 5395-5412, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34955062

RESUMEN

Aflatoxins are carcinogenic secondary metabolites produced by Aspergillus section Flavi that contaminates a wide variety of food and feed products and is responsible for serious health and economic consequences. Fermented foods are prepared with a wide variety of substrates over a long fermentation time and are thus vulnerable to contamination by aflatoxin-producing fungi, leading to the production of aflatoxin B1. The mitigation and control of aflatoxin is currently a prime focus for developing safe aflatoxin-free food. This review summarizes the role of major aflatoxin-degrading enzymes such as laccase, peroxidase, and lactonase, and microorganisms in the context of their application in food. A putative mechanism of enzyme-mediated aflatoxin degradation and toxicity evaluation of the degraded products are also extensively discussed to evaluate the safety of degradation processes for food applications. The review also describes aflatoxin-degrading microorganisms isolated from fermented products and investigates their applicability in food as aflatoxin preventing agents. Furthermore, a summary of recent technological advancements in protein engineering, nanozymes, in silico and statistical optimization approaches are explored to improve the industrial applicability of aflatoxin-degrading enzymes.


Asunto(s)
Aflatoxinas , Aflatoxina B1/metabolismo , Aflatoxina B1/toxicidad , Aflatoxinas/análisis , Aspergillus/metabolismo , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Hongos/metabolismo , Inactivación Metabólica
9.
Nanomaterials (Basel) ; 13(1)2022 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-36616061

RESUMEN

Regular water quality measurements are essential to the public water supply. Moreover, selective free chlorine (disinfectant) level monitoring without an interfering agent is necessary. The present work aimed to fabricate poly(caffeic acid) (p-CFA) coated on an electrochemically reduced graphene oxide (ERGO) surface for the selective detection of free chlorine. Electron microscopy and various spectroscopic techniques confirmed the p-CFA@ERGO/glassy carbon (GC) electrode. The p-CFA@ERGO/GC coated probe surface coverage was calculated to be 4.75 × 10-11 mol cm-2. The p-CFA@ERGO/GC showed superior catechol/o-quinone oxidation/reduction peaks for electrocatalytic free chlorine determination. The performance of the developed sensor electrode was outstanding, with an extensive range of free chlorine detection (20 µM to 20 mM), high sensitivity (0.0361 µA µM-1), and low detection limit (0.03 µM). The p-CFA@ERGO/GC capability of the realist water samples, such as the tested commercial and tap water, yielded a good range of recovery (from 98.5% to 99.9%). These values align with the standard N,N'-diethyl-p-phenylenediamine reagent method results.

10.
Nanomaterials (Basel) ; 11(12)2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34947557

RESUMEN

Mixed metal sulfides exhibit outstanding electrochemical performance compared to single metal sulfides and mixed metal oxides because of their richer redox reactions and high electronic conductivity. In the present study, Zn-Co-S nanostrip cluster arrays were formed from ZnCo2O4 grown on Ni foam by an anion exchange reaction using a two-step hydrothermal process. Morphological characterization confirmed that the Zn-Co-S nanostrip cluster arrays had grown homogeneously on the skeleton of the 3D Ni foam. The length of the nanostrip was approximately 8 µm, and the width ranged from 600 to 800 nm. The Ni foam-supported Zn-Co-S nanostrip cluster arrays were assessed directly for electrochemical supercapacitor applications. Compared to ZnCo2O4, the Zn-Co-S electrode exhibited a three-fold higher specific capacity of 830 C g-1 at a specific current of 2.0 A g-1. The higher polarizability, lower electro-negativity, and larger size of the S2- ion played an important role in substituting oxygen with sulfur, which enhanced the performance. The Zn-Co-S//AC hybrid device delivered a maximum specific energy of 19.0 Wh kg-1 at a specific power of 514 W kg-1. The remarkable performance of Zn-Co-S nanostrip cluster arrays highlights their potential as a positive electrode for hybrid supercapacitor applications.

11.
Anal Chim Acta ; 1141: 71-82, 2021 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-33248664

RESUMEN

Robust, highly selective, and sensitive sensor devices are in high demand for the detection of bioactive molecules. Bioactive molecules are quantified by the electrochemical approach in the presence of other interference species, presenting a significant challenge to researchers. In this study, molecularly imprinted polymer (MIP) was prepared using the electrochemical method in a methanol/water solution mixture. The MIP on the electrochemically reduced graphene oxide (ERGO) surface exhibited hornlike morphology in contrast to the bare GC obtained, forming irregular bulky structures with a size range of 0.8-2.1 µm. The domperidone (DP) binding/extraction from MIP@ERGO was studied using ex situ Fourier transform infrared and X-ray photoelectron spectroscopy. The hornlike MIP@ERGO/GC revealed a higher heterogeneous electron transfer rate constant and DP antiemetic drug oxidation current response compared with the MIP/GC and non-imprinted polymer (NIP/GC) electrodes. The hornlike MIP@ERGO/GC electrode fabrication was optimized in terms of the pyrrole polymerization cyclic voltammetry cycle number, monomer/template concentration, and incubation times. The fabricated MIP@ERGO/GC electrode demonstrated a wide concentration range of DP detection (from 0.5 to 17.2 µM), and the limit of detection was found to be 3.8 nM, with a signal-to-noise ratio of 3. Moreover, the MIP@ERGO/GC electrode had excellent DP selectivity (with an imprinting factor of 4.20), even in the presence of ascorbic acid, uric acid, dopamine, xanthine, gelatin, glucose, sucrose, l-cysteine, folic acid, K+, Na+, Ca2+, CO32-, SO42-, and NO3- interferences. The MIP@ERGO/GC electrode was tested on a human urine sample, and DP recovery ranges between 98.4% and 100.87% were obtained.


Asunto(s)
Antieméticos , Impresión Molecular , Preparaciones Farmacéuticas , Técnicas Electroquímicas , Electrodos , Grafito , Humanos , Polímeros
12.
ACS Appl Mater Interfaces ; 11(8): 8040-8050, 2019 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-30714716

RESUMEN

Recently, enhancement of the energy density of a supercapacitor is restricted by the inferior capacitance of negative electrodes, which impedes the commercial development of high-performance symmetric and asymmetric supercapacitors. This article introduces the in situ bulk-quantity synthesis of hydrophilic, porous, graphitic sulfur-doped carbon nano-onions (S-CNO) using a facile flame-pyrolysis technique and evaluated its potential applications as a high-performance supercapacitor electrode in a symmetric device configuration. The high-surface wettability in the as-prepared state enables the formation of highly suspended active conducting material S-CNO ink, which eliminates the routine use of binders for the electrode preparation. The as-prepared S-CNO displayed encouraging features for electrochemical energy storage applications with a high specific surface area (950 m2 g-1), ordered mesoporous structure (∼3.9 nm), high S-content (∼3.6 at. %), and substantial electronic conductivity, as indicated by the ∼80% sp2 graphitic carbon content. The in situ sulfur incorporation into the carbon framework of the CNO resulted in a high-polarized surface with well-distributed reversible pseudosites, increasing the electrode-electrolyte interaction and improving the overall conductivity. The S-CNOs showed a specific capacitance of 305 F g-1, an energy density of 10.6 W h kg-1, and a power density of 1004 W kg-1 at an applied current density of 2 A g-1 in a symmetrical two-electrode cell configuration, which is approximately three times higher than that of the pristine CNO-based device in a similar electrochemical testing environment. Even at 11 A g-1, the S-CNO||S-CNO device rendered an energy density (6.1 W h kg-1) at a deliverable power density of 5.5 kW kg-1, indicating a very good rate capability and power management during peak power delivery applications. Furthermore, it showed a high degree of electrochemical reversibility with excellent cycling stability, retaining ∼95% of its initial capacitance after more than 10 000 repetitive charge-discharge cycles at an applied current density of 5 A g-1.

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