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1.
ACS Omega ; 9(34): 36314-36325, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39220486

RESUMO

The wide band gap γ-Bi2MoO6 (BMO) has tremendous potential in emergent solar harvesting applications. Here we present a combined experimental-first-principles density functional theory (DFT) approach to probe physical properties relevant to the light sensitivity of BMO like dynamic and structural stability, Raman and infrared absorption modes, value and nature of band gap (i.e., direct or indirect), dielectric constant, and optical absorption, etc. We solvothermally synthesized wide band gap Pca21 phase pure BMO (≳3 eV) for two different pH values of 7 and 9. The structural parameters were correlated with the stability of BMO derived from elastic tensor simulations. The desired dynamical stability at T = 0 K was established from the phonon vibrational band structure using a finite difference-based supercell approach. The DFT-based Raman modes and phonon density of states (DOS) reliably reproduced the experimental Raman and infrared absorption. The electronic DOS calculated from Heyd-Scuseria-Ernzerhof HSE06 with van der Waals (vdW) and relativistic spin-orbit coupling (SOC) corrections produced a good agreement with the band gap obtained from diffuse reflectance spectroscopy (DRS). The optical absorption obtained from the complex dielectric constant for the HSE06+SOC+vdW potential closely resembled the DRS-derived absorption of BMO. The BMO shows ∼43% photocatalytic efficiency in degrading methylene blue dye under 75 min optical illumination. This combined DFT-experimental approach may provide a better understanding of the properties of BMO relevant to solar harvesting applications.

2.
Brain Inform ; 11(1): 17, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837089

RESUMO

Neuromarketing is an emerging research field that aims to understand consumers' decision-making processes when choosing which product to buy. This information is highly sought after by businesses looking to improve their marketing strategies by understanding what leaves a positive or negative impression on consumers. It has the potential to revolutionize the marketing industry by enabling companies to offer engaging experiences, create more effective advertisements, avoid the wrong marketing strategies, and ultimately save millions of dollars for businesses. Therefore, good documentation is necessary to capture the current research situation in this vital sector. In this article, we present a systematic review of EEG-based Neuromarketing. We aim to shed light on the research trends, technical scopes, and potential opportunities in this field. We reviewed recent publications from valid databases and divided the popular research topics in Neuromarketing into five clusters to present the current research trend in this field. We also discuss the brain regions that are activated when making purchase decisions and their relevance to Neuromarketing applications. The article provides appropriate illustrations of marketing stimuli that can elicit authentic impressions from consumers' minds, the techniques used to process and analyze recorded brain data, and the current strategies employed to interpret the data. Finally, we offer recommendations to upcoming researchers to help them investigate the possibilities in this area more efficiently in the future.

3.
RSC Adv ; 13(51): 36130-36143, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38090076

RESUMO

Here we synthesized Bi2WO6 (BWO) using both solid-state reaction (SBWO) and hydrothermal (HBWO-U and HBWO-S) methods. The orthorhombic Pca21 phase purity in all samples is confirmed from Rietveld refinement of X-ray diffraction data, Raman spectroscopy, and Fourier transform infrared spectroscopy. The HBWO-U and HBWO-S morphology revealed rectangular, spherical, and rod-like features with an average particle size of 55 nm in field emission scanning electron micrographs. A high-resolution transmission electron micrograph showed spherical-shaped particles in the HBWO-U sample with an average diameter of ∼10 nm. The diffuse reflectance-derived indirect electronic band gaps lie within the 2.79-3.23 eV range. The BWO electronic structure is successfully modeled by Hubbard interaction Ud and Up corrected Perdew-Burke-Ernzerhof generalized gradient approximation GGA-PBE+Ud+Up with van der Waals (vdW) force in effect. The optimized (Ud, Up) values are further justified by tuning the Hartree-Fock (HF) exact-exchange mixing parameter αHF from 25% in Heyd-Scuseria-Ernzerhof (HSE06) to 20% in the PBE-HF20% functional. Moreover, no inconsistencies were seen in the GGA-PBE+Ud+Up+vdW simulated crystallographic parameters, and the elastic tensor, phonon, and linear optical properties. Overall, the computationally cheap GGA-PBE+Ud+Up with vdW force may have successfully probed the physical properties of BWO.

4.
RSC Adv ; 13(21): 14291-14305, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37180022

RESUMO

Here we present a comprehensive density functional theory (DFT) based ab initio study of copper bismuth oxide CuBi2O4 (CBO) in combination with experimental observations. The CBO samples were prepared following both solid-state reaction (SCBO) and hydrothermal (HCBO) methods. The P4/ncc phase purity of the as-synthesized samples was corroborated by Rietveld refinement of the powdered X-ray diffraction measurements along with Generalized Gradient Approximation of Perdew-Burke-Ernzerhof (GGA-PBE) and the Hubbard interaction U corrected GGA-PBE+U relaxed crystallographic parameters. Scanning and field emission scanning electron micrographs confirmed the particle size of the SCBO and HCBO samples to be ∼250 and ∼60 nm respectively. The GGA-PBE and GGA-PBE+U derived Raman peaks are in better agreement with that of the experimentally observed ones when compared to local density approximation based results. The DFT derived phonon density of states conforms with the absorption bands in Fourier transform infrared spectra. Both structural and dynamic stability criteria of the CBO are confirmed by elastic tensor and density functional perturbation theory-based phonon band structure simulations respectively. The CBO band gap underestimation of GGA-PBE as compared to UV-vis diffuse reflectance derived 1.8 eV was eliminated by tuning the U and the Hartree-Fock exact-exchange mixing parameter αHF in GGA-PBE+U and Heyd-Scuseria-Ernzerhof (HSE06) hybrid functionals respectively. The HSE06 with αHF = 14% yields the optimum linear optical properties of CBO in terms of the dielectric function, absorption, and their derivatives as compared to that of GGA-PBE and GGA-PBE+U functionals. Our as-synthesized HCBO shows ∼70% photocatalytic efficiency in degrading methylene blue dye under 3 h optical illumination. This DFT-guided experimental approach to CBO may help to gain a better understanding of its functional properties.

5.
RSC Adv ; 13(8): 5576-5589, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36798614

RESUMO

Here we present a detailed ab initio study of two experimentally synthesized bismuth niobate BiNbO4 (BNO) polymorphs within the framework of density functional theory (DFT). We synthesized orthorhombic α-BNO and triclinic ß-BNO using a solid-state reaction technique. The underlying Pnna and P1̄ crystal symmetries along with their respective phase purity have been confirmed from Rietveld refinement of the powdered X-ray diffraction measurements in combination with generalized gradient approximation of Perdew-Burke-Ernzerhof (GGA-PBE) based DFT simulations. The scanning electron micrographs revealed average grain sizes to be 500 nm and 1 µm for α-BNO and ß-BNO respectively. The energy-dispersive X-ray spectroscopy identified the Bi, Nb, and O with proper stoichiometry. The phase purity of the as-synthesized samples was further confirmed by comparing the local density approximation (LDA) norm-conserving pseudo-potential based DFT-simulated Raman peaks with that of experimentally measured ones. The relevant bond vibrations detected in Fourier transform infrared spectroscopy were matched with GGA-PBE derived phonon density of states simulation for both polymorphs. The structural stability and the charge dynamics of the polymorphs were verified from elastic stress and born charge tensor simulations respectively. The dynamical stability of the α-BNO was confirmed from phonon band structure simulation using density functional perturbation theory with Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional. The electronic band gaps of 3.08 and 3.36 eV for α-BNO and ß-BNO measured from UV-Vis diffuse reflectance measurements were matched with the sophisticated HSE06 band structure simulation by adjusting the Hartree-Fock exchange parameter. Both GGA-PBE and HSE06 functional were used to simulate complex dielectric function and its derivatives with the help of Fermi's golden rule to define the optical properties in the linear regime. All these may have provided a rigorous theoretical analysis for the experimentally synthesized α-BNO and ß-BNO polymorphs.

6.
Digit Health ; 8: 20552076221109545, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874862

RESUMO

Background: Prior to the COVID-19 pandemic, about half of patients from populations that sought care in neurology tried complementary and integrative therapies (CITs). With the increased utilization of telehealth services, we sought to determine whether patients also increased their use of virtual CITs. Methods: We examined datasets from two separate cross-sectional surveys that included cohorts of patients with neurological disorders. One was a dataset from a study that examined patient and provider experiences with teleneurology visits; the other was a study that assessed patients with a history of COVID-19 infection who presented for neurologic evaluation. We assessed and reported the use of virtual (and non-virtual) CITs using descriptive statistics, and determined whether there were clinical characteristics that predicted the use of CITs using logistic regression analyses. Findings: Patients who postponed medical treatment for non-COVID-19-related problems during the pandemic were more likely to seek CITs. Virtual exercise, virtual psychotherapy, and relaxation/meditation smartphone applications were the most frequent types of virtual CITs chosen by patients. In both studies, age was a key demographic factor associated with mobile/virtual CIT usage. Interpretations: Our investigation demonstrates that virtual CIT-related technologies were utilized in the treatment of neurologic conditions during the pandemic, particularly by those patients who deferred non-COVID-related care.

7.
JMIR Mhealth Uhealth ; 10(6): e36761, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35727625

RESUMO

BACKGROUND: There are thousands of apps for individuals struggling with headache, insomnia, and pain, but it is difficult to establish which of these apps are best suited for patients' specific needs. If clinicians were to have access to a platform that would allow them to make an informed decision on the efficacy and feasibility of smartphone apps for patient care, they would feel confident in prescribing specific apps. OBJECTIVE: We sought to evaluate the quality of apps for some of the top common, disabling neurologic conditions (headache, insomnia, and pain) based on principles derived from the American Psychiatric Association's (APA) app evaluation model. METHODS: We used the Mobile Health Index and Navigation database and expanded upon the database's current supported conditions by adding 177 new app entries. Each app was rated for consistency with the APA's app evaluation model, which includes 105 objective questions based on the following 5 major classes of consideration: (1) accessibility, (2) privacy and security, (3) clinical foundation, (4) engagement style, and (5) interoperability. These characteristics were evaluated to gain a broader understanding of the significant features of each app category in comparison against a control group. RESULTS: Approximately 90% (187/201) of all apps evaluated were free to download, but only 50% (63/201) of headache- and pain-related apps were truly free. Most (87/106, 81%) sleep apps were not truly free to use. The apps had similar limitations with limited privacy, accessibility, and crisis management resources. For example, only 17% (35/201) of the apps were available in Spanish. The apps offered mostly self-help tools with little tailoring; symptom tracking was the most common feature in headache- (32/48, 67%) and pain-related apps (21/47, 45%), whereas mindfulness was the most common feature in sleep-related apps (73/106, 69%). CONCLUSIONS: Although there are many apps for headache, pain, and insomnia, all 3 types of apps have room for improvement around accessibility and privacy. Pain and headache apps share many common features, whereas insomnia apps offer mostly mindfulness-based resources. Given the many available apps to pick from, clinicians and patients should seek apps that offer the highest-quality features, such as complete privacy, remedial features, and the ability to download the app at no cost. These results suggest that there are many opportunities for the improvement of apps centered on headache, insomnia, and pain.


Assuntos
Aplicativos Móveis , Distúrbios do Início e da Manutenção do Sono , Telemedicina , Estudos Transversais , Cefaleia/diagnóstico , Cefaleia/terapia , Humanos , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Distúrbios do Início e da Manutenção do Sono/terapia
8.
SN Comput Sci ; 2(6): 453, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34522897

RESUMO

Due to the spread of COVID-19, global measures such as lockdown and limits on public transit, entertainment, the closure of all educational institutions, and religious practices have been imposed in early 2020. During and after the COVID-19 disease outbreak, the first target ought to be safer road travel and zero fatalities. This paper general overviews the effects of the government's COVID-19 control measures on Bangladesh's transportation system and road safety during the period March 2020-2021. Secondary data sources, newspaper articles, WHO, Worldometer, Institute of Epidemiology, Disease Control and Research (IEDCR) websites, and relevant research papers were used to compile this article. The various restriction policies would have a negative impact on the transportation sector's finances, exacerbating the economic crisis that public transportation and airline operators in Bangladesh are experiencing. This study found that restricting mobility reduces road traffic deaths and injuries by a small amount, but that accidents continue to occur during the lockdown period in Bangladesh.

9.
Life Sci ; 86(19-20): 726-32, 2010 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-20226794

RESUMO

AIMS: Effect of mitochondrial permeability transition (MPT) inhibitors on mitochondrial membrane-bound glutathione transferase (mtMGST1) activity in rat liver was investigated in vitro. MAIN METHODS: When mitochondria were incubated with MPT inhibitors, mtMGST1 activity was decreased dose dependently and their 50% inhibition concentration (IC(50)) were 1.2 microM (cyclosporin A; CsA), 31 microM (bongkrekic acid; BKA), 1.8 mM (ADP), and 3.2 mM (ATP). The decrease of mtMGST1 activity by the MPT inhibitors was not observed in the presence of detergent Triton X-100. On the contrary, mtMGST1 inhibition by GST inhibitors such as cibacron blue (IC(50), 4.2 microM) and S-hexylglutathione (IC(50), 480 microM) was not affected in the presence of detergent. Although mtMGST1 resides in both the inner (IMM) and outer mitochondrial membranes (OMM), only mtMGST1 in the IMM was inhibited by the MPT inhibitors in the absence of detergent. GST inhibitors decreased mtMGST1 activity both in the IMM and OMM regardless of the presence or absence of detergent. Cytosolic GSTs and microsomal MGST1 were not inhibited by the MPT inhibitors. KEY FINDINGS: These results indicate that mtMGST1 is inhibited by MPT inhibitors through membrane components, not directly by the inhibitors. SIGNIFICANCE: Since CsA binds to cyclophilin D (Cyp-D) in the mitochondrial matrix whereas BKA or ADP binds to adenine nucleotide translocator (ANT) in the IMM, it was suggested that mtMGST1 in the IMM interacts with Cyp-D/ANT and the binding of MPT inhibitors to Cyp-D or ANT causes their conformational change followed by an alteration of mtMGST1 conformation, resulting in decreasing mtMGST1 activity.


Assuntos
Ciclofilinas/metabolismo , Ciclosporina/farmacologia , Glutationa Transferase/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Membranas Mitocondriais/metabolismo , Difosfato de Adenosina/administração & dosagem , Difosfato de Adenosina/farmacologia , Animais , Ácido Bongcréquico/administração & dosagem , Ácido Bongcréquico/farmacologia , Peptidil-Prolil Isomerase F , Ciclosporina/administração & dosagem , Citosol/efeitos dos fármacos , Citosol/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Glutationa Transferase/metabolismo , Concentração Inibidora 50 , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Translocases Mitocondriais de ADP e ATP/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Ligação Proteica , Conformação Proteica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
10.
Toxicol Appl Pharmacol ; 235(1): 77-85, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19111564

RESUMO

We recently reported that the glutathione transferase in rat liver mitochondrial membranes (mtMGST1) is activated by S-glutathionylation and the activated mtMGST1 contributes to the mitochondrial permeability transition (MPT) pore and cytochrome c release from mitochondria [Lee, K.K., Shimoji, M., Quazi, S.H., Sunakawa, H., Aniya, Y., 2008. Novel function of glutathione transferase in rat liver mitochondrial membrane: role for cytochrome c release from mitochondria. Toxcol. Appl. Pharmacol. 232, 109-118]. In the present study we investigated the effect of reactive oxygen species (ROS), generator gallic acid (GA) and GST inhibitors on mtMGST1 and the MPT. When rat liver mitochondria were incubated with GA, mtMGST1 activity was increased to about 3 fold and the increase was inhibited with antioxidant enzymes and singlet oxygen quenchers including 1,4-diazabicyclo [2,2,2] octane (DABCO). GA-mediated mtMGST1 activation was prevented by GST inhibitors such as tannic acid, hematin, and cibacron blue and also by cyclosporin A (CsA). In addition, GA induced the mitochondrial swelling which was also inhibited by GST inhibitors, but not by MPT inhibitors CsA, ADP, and bongkrekic acid. GA also released cytochrome c from the mitochondria which was inhibited completely by DABCO, moderately by GST inhibitors, and somewhat by CsA. Ca(2+)-mediated mitochondrial swelling and cytochrome c release were inhibited by MPT inhibitors but not by GST inhibitors. When the outer mitochondrial membrane was isolated after treatment of mitochondria with GA, mtMGST1 activity was markedly increased and oligomer/aggregate of mtMGST1 was observed. These results indicate that mtMGST1 in the outer mitochondrial membrane is activated by GA through thiol oxidation leading to protein oligomerization/aggregation, which may contribute to the formation of ROS-mediated, CsA-insensitive MPT pore, suggesting a novel mechanism for regulation of the MPT by mtMGST1.


Assuntos
Glutationa Transferase/metabolismo , Mitocôndrias Hepáticas/enzimologia , Membranas Mitocondriais/metabolismo , Animais , Antioxidantes/farmacologia , Cálcio/farmacologia , Citocromos c/metabolismo , Ativação Enzimática/efeitos dos fármacos , Ácido Gálico/farmacologia , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Permeabilidade , Ratos , Ratos Sprague-Dawley
11.
Toxicol Appl Pharmacol ; 232(1): 109-18, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18634816

RESUMO

Microsomal glutathione transferase (MGST1) is activated by oxidative stress. Although MGST1 is found in mitochondrial membranes (mtMGST1), there is no information about the oxidative activation of mtMGST1. In the present study, we aimed to determine whether mtMGST1 also undergoes activation and about its function. When rats were treated with galactosamine/lipopolysaccharide (GalN/LPS), mtMGST1 activity was significantly increased, and the increased activity was reduced by the disulfide reducing agent dithiothreitol. In mitochondria from GalN/LPS-treated rats, disulfide-linked mtMGST1 dimer and mixed protein glutathione disulfides (glutathionylation) were detected. In addition, cytochrome c release from mitochondria isolated from GalN/LPS-treated rats was observed, and the release was inhibited by anti-MGST1 antibodies. Incubation of mitochondria from control rats with diamide and diamide plus GSH in vitro resulted in dimer- and mixed disulfide bond-mediated activation of mtMGST1, respectively. The activation of mtMGST1 by diamide plus GSH caused cytochrome c release from the mitochondria, and the release was prevented by treatment with anti-MGST1 antibodies. In addition, diamide plus GSH treatment caused mitochondrial swelling accompanied by cytochrome c release, which was inhibited by cyclosporin A (CsA) and bongkrekic acid (BKA), inhibitors of the mitochondrial permeability transition (MPT) pore. Furthermore, mtMGST1 activity was also inhibited by CsA and BKA. These results indicate that mtMGST1 is activated through mixed disulfide bond formation that contributes to cytochrome c release from mitochondria through the MPT pore.


Assuntos
Citocromos c/metabolismo , Dissulfetos/metabolismo , Glutationa Transferase/metabolismo , Mitocôndrias Hepáticas/enzimologia , Membranas Mitocondriais/enzimologia , Animais , Apoptose , Western Blotting , Ácido Bongcréquico/farmacologia , Ciclosporina/farmacologia , Diamida/farmacologia , Dimerização , Ditiotreitol/farmacologia , Ativação Enzimática , Galactosamina/administração & dosagem , Glutationa/metabolismo , Lipopolissacarídeos/administração & dosagem , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/patologia , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Poro de Transição de Permeabilidade Mitocondrial , Dilatação Mitocondrial , Oxirredução , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Substâncias Redutoras/farmacologia , Reagentes de Sulfidrila/farmacologia , Fatores de Tempo , Tirosina/análogos & derivados , Tirosina/metabolismo
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