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1.
PLoS One ; 19(4): e0298620, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625847

RESUMO

In this manuscript, we developed a nonlinear fractional order Ebola virus with a novel piecewise hybrid technique to observe the dynamical transmission having eight compartments. The existence and uniqueness of a solution of piecewise derivative is treated for a system with Arzel'a-Ascoli and Schauder conditions. We investigate the effects of classical and modified fractional calculus operators, specifically the classical Caputo piecewise operator, on the behavior of the model. A model shows that a completely continuous operator is uniformly continuous, and bounded according to the equilibrium points. The reproductive number R0 is derived for the biological feasibility of the model with sensitivity analysis with different parameters impact on the model. Sensitivity analysis is an essential tool for comprehending how various model parameters affect the spread of illness. Through a methodical manipulation of important parameters and an assessment of their impact on Ro, we are able to learn more about the resiliency and susceptibility of the model. Local stability is established with next Matignon method and global stability is conducted with the Lyapunov function for a feasible solution of the proposed model. In the end, a numerical solution is derived with Newton's polynomial technique for a piecewise Caputo operator through simulations of the compartments at various fractional orders by using real data. Our findings highlight the importance of fractional operators in enhancing the accuracy of the model in capturing the intricate dynamics of the disease. This research contributes to a deeper understanding of Ebola virus dynamics and provides valuable insights for improving disease modeling and public health strategies.


Assuntos
Ebolavirus , Epidemias , Doença pelo Vírus Ebola , Humanos , Doença pelo Vírus Ebola/epidemiologia , Aprendizagem , Saúde Pública
3.
Sci Rep ; 14(1): 2175, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272984

RESUMO

Respiratory syncytial virus (RSV) is the cause of lung infection, nose, throat, and breathing issues in a population of constant humans with super-spreading infected dynamics transmission in society. This research emphasizes on examining a sustainable fractional derivative-based approach to the dynamics of this infectious disease. We proposed a fractional order to establish a set of fractional differential equations (FDEs) for the time-fractional order RSV model. The equilibrium analysis confirmed the existence and uniqueness of our proposed model solution. Both sensitivity and qualitative analysis were employed to study the fractional order. We explored the Ulam-Hyres stability of the model through functional analysis theory. To study the influence of the fractional operator and illustrate the societal implications of RSV, we employed a two-step Lagrange polynomial represented in the generalized form of the Power-Law kernel. Also, the fractional order RSV model is demonstrated with chaotic behaviors which shows the trajectory path in a stable region of the compartments. Such a study will aid in the understanding of RSV behavior and the development of prevention strategies for those who are affected. Our numerical simulations show that fractional order dynamic modeling is an excellent and suitable mathematical modeling technique for creating and researching infectious disease models.


Assuntos
Doenças Transmissíveis , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Humanos , Pescoço , Nariz
4.
Int J Biol Macromol ; 254(Pt 3): 127954, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951425

RESUMO

Sodium alginate (SA) is a biodegradable macromolecule which is used to synthesize nanocomposites and their further use as catalysis. Zinc oxide (ZnO) and nitrogen doped carbon nitride (ND-C3N4) nanoparticles are prepared using solvothermal and hydrothermal methods, respectively. ZnO/ND-C3N4/SA nanocomposites are successfully synthesized by employing in-situ polymerization. The presence of essential functional groups is confirmed by Fourier transform infrared (FTIR) spectroscopic analysis. Controlled spherical morphology for ZnO nanoparticles, with an average diameter of ∼52 nm, is shown by Scanning electron microscopic (SEM) analysis, while rice-like grain structure with an average grain size ∼62 nm is exhibited by ND-C3N4 nanoparticles. The presence of required elements is confirmed by Energy dispersive X-ray spectroscopic (EDX) analysis. The crystalline nature of nanocomposites is verified by X-ray diffraction spectroscopic (XRD) analysis. The investigation of the catalytic efficiency for degradation and reduction of various organic dyes is carried out on nanoparticles and nanocomposites. Thorough examination and comparison of parameters, such as apparent rate constant (kapp), reduction time, percentage reduction, reduced concentration and half-life, are conducted for all substrates. The nanocomposites show greater efficiency than nanoparticles in both reactions: catalytic reduction and catalytic degradation.


Assuntos
Nanocompostos , Óxido de Zinco , Óxido de Zinco/química , Alginatos , Espectroscopia de Infravermelho com Transformada de Fourier , Nanocompostos/química , Catálise
5.
RSC Adv ; 13(42): 29632-29644, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37822660

RESUMO

Iron-nickel bimetallic nanoparticles (Fe-Ni BMNPs) are prepared by combining two different metals by using the bottom-up approach. The resulting material has entirely different properties as compared to both the metals. The product is examined by using different analytical instruments such as.; scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), MDIJADE, ORIGIN pro to characterize their morphology, crystallinity and elemental composition and the final data has been statistically analyzed. SEM findings show that most nanoparticles are irregular in form and range in size from 10 nm to 100 nm. The findings of the TEM verified that the particles between 10 nm and 50 nm are irregular in size shape. The products acquired utilized as a fuel additive to monitor oil effectiveness by studying various parameters. The degradation of methylene blue dye depends directly on the concentration of the nanocatalyst. Different parameters also use the freshly prepared bimetallic nanocatalyst to investigate the efficacy of the kerosene fuel. By adding a tiny quantity of the nanocatalyst, the value of the flash point and fire point is significantly reduced. The nanocatalyst does not affect the cloud point and pour point to a large extent. The bimetallic nanocatalyst therefore has very excellent catalytic characteristics.

6.
J Microencapsul ; 39(7-8): 638-653, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36398734

RESUMO

This study aimed to formulate the green, sustainable, and ecofriendly nanobiopesticides of Azadirachta indica with enhanced pest control efficacy. Nanoprecipitation method was used for the development of nanobiopesticides. Optimisation was done by response surface methodology. Nanoformulations were characterised by zetasizer, scanning electron microscopy, energy dispersive x-ray spectroscopy, atomic force microscopy, and Fourier transform infrared spectroscopy. Pesticidal potential of nanosuspensions was evaluated by insecticide impregnated filter paper method. Optimised nanobiopesticide showed an average particle size of 275.8 ± 0.95 nm, polydispersity index (PDI) 0.351 ± 0.002, and zeta potential of -33 ± 0.90 mV. Nanobiopesticides exhibited significantly higher mortality rates of 86.81 ± 3.04 and 84.97 ± 2.83% against Tribolium castaneum and Ryzopertha dominica, respectively, as compared to their crude extract. Minor change in particle size from 275.8 ± 0.95 to 298.8 ± 1.00 nm and PDI from 0.351 ± 0.002 to 0.445 ± 0.02 were observed after 3 months of storage at 4 °C. Pesticidal efficacy of A. indica was significantly enhanced by the formulation of its nanobiopesticides.


Assuntos
Azadirachta , Besouros , Inseticidas , Praguicidas , Tribolium , Animais , Triticum , Dominica , Inseticidas/farmacologia , Praguicidas/farmacologia
7.
Environ Technol ; : 1-11, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36288459

RESUMO

Three phases (α, ß, and γ) of manganese dioxide (MnO2) are successfully stabilized in a single entity for the first time. For this purpose, Citrullus colocynthis (bitter apple) extract is used as a natural surfactant in green synthesis. MnO2 nanoparticles were synthesized in the presence and absence of plant extracts under the same conditions. The morphology of both products is analysed by SEM and STEM to understand the role of plant extract in controlling the morphology of particles. The crystallinity and composition are analysed by XRD and confirmed that the product is composed of multiple phases α, ß, and γ. The reduction of dyes and nitroarenes is studied using MnO2 nanoparticles (green and chemical products) as catalysts. The apparent rate constant, a percentage reduction, time reduction and reduced concentration compare the activities of both catalysts. After comparative data analysis, the catalytic reduction of picric acid is found fastest among all the substrates. All the results are analysed based on structure, functional group and affinity towards catalysts.

8.
Environ Technol ; 42(8): 1187-1195, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31448700

RESUMO

Manganese-tin bimetallic oxide (MnSnO3) is synthesized by the solvothermal approach using manganese acetate and stannic chloride as precursors and urea as a precipitating agent in an aqueous medium. The crystallinity, purity and lattice parameters of the product are analysed by the X-ray diffraction analysis. The morphology of the product is analysed with the help of a scanning electron microscopy. The synthesized product is used as a fuel additive and catalyst. Synthesized MnSnO3 is used as a catalyst for the degradation of an organic dye Congo red in the aqueous medium. Catalytic degradation is monitored at different concentrations of the catalyst and hydrogen peroxide. Moreover, the role of MnSnO3, as an additive in diesel fuel, is studied. The efficiency of the modified fuel is analysed by studying the different parameters such as flash point, fire point, cloud point, pour point, calorific values and specific gravity. The values of these parameters change significantly by changing the dosage of the additive.


Assuntos
Manganês , Óxidos , Catálise , Gasolina , Compostos de Estanho
9.
ACS Omega ; 5(37): 24125-24137, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32984735

RESUMO

This work was inspired by a previous report [Janjua, M. R. S. A. Inorg. Chem. 2012, 51, 11306-11314] in which the optoelectronic properties were improved with an acceptor bearing heteroaromatic rings. Herein, we have designed four novel Y-series non-fullerene acceptors (NFAs) by end-capped acceptor modifications of a recently synthesized 15% efficient Y21 molecule for better optoelectronic properties and their potential use in solar cell applications. Density functional theory (DFT) along with time-dependent density functional theory (TDDFT) at the B3LYP/6-31G(d,p) level of theory is used to calculate the band gap, exciton binding energy along with transition density matrix (TDM) analysis, reorganizational energy of electrons and holes, and absorption maxima and open-circuit voltage of investigated molecules. In addition, the PM6:YA1 complex is also studied to understand the charge shifting from the donor polymer PM6 to the NFA blend. Results of all parameters suggest that the DA'D electron-deficient core and effective end-capped acceptors in YA1-YA4 molecules form a perfect combination for effective tuning of optoelectronic properties by lowering frontier molecular orbital (FMO) energy levels, reorganization energy, and binding energy and increasing the absorption maximum and open-circuit voltage values in selected molecules (YA1-YA4). The combination of extended conjugation and excellent electron-withdrawing capability of the end-capped acceptor moiety in YA1 makes YA1 an excellent organic solar cell (OSC) candidate owing to promising photovoltaic properties including the lowest energy gap (1.924 eV), smallest electron mobility (λe = 0.0073 eV) and hole mobility (λh = 0.0083 eV), highest λmax values (783.36 nm (in gas) and 715.20 nm (in chloroform) with lowest transition energy values (E x) of 1.58 and 1.73 eV, respectively), and fine open-circuit voltage (V oc = 1.17 V) with respect to HOMOPM6-LUMOacceptor. Moreover, selected molecules are observed to have better photovoltaic properties than Y21, thus paving the way for experimentalists to look for future developments of Y-series-based highly efficient solar cells.

10.
Oxid Med Cell Longev ; 2018: 4643736, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30581531

RESUMO

The aim of this study was to identify and characterize the bioactive compounds of Coriandrum sativum responsible for the treatment of hypertension and to explore their mechanism of action as angiotensin-converting enzyme (ACE) inhibitors. Bioactive fractions like alkaloids, flavonoids, steroids, and tannins were extracted and evaluated for their ACE inhibition potential. Among them, only flavonoid-rich fraction showed high ACE inhibition potential with IC50 value of 28.91 ± 13.42 µg/mL. The flavonoids were characterized through LC-ESI-MS/MS. Seventeen flavonoids were identified in this fraction of Coriandrum sativum in negative ionization mode which includes pinocembrin, apigenin, pseudobaptigenin, galangin-5-methyl ether, quercetin, baicalein trimethyl ether, kaempferol dimethyl ether, pinobanksin-5-methylether-3-O-acetate, pinobanksin-3-O-pentenoate, pinobanksin-3-O-phenylpropionate, pinobanksin-3-O-pentanoate, apigenin-7-O-glucuronoide, quercetin-3-O-glucoside, apigenin-3-O-rutinoside, rutin, isorhamnetin-3-O-rutinoside, and quercetin dimethyl ether-3-O-rutinoside, while six flavonoids including daidzein, luteolin, pectolinarigenin, apigenin-C-glucoside, kaempferol-3-7-dimethyl ether-3-O-glucoside, and apigenin-7-O-(6-methyl-beta-D-glucoside) were identified in positive ionization mode. The results of this study revealed that Coriandrum sativum is a valuable functional food that possesses a number of therapeutic flavonoids with ACE inhibition potential that can manage blood pressure very efficiently.


Assuntos
Coriandrum/química , Flavonoides/química , Flavonoides/farmacologia , Peptidil Dipeptidase A/metabolismo , Animais , Apigenina/química , Apigenina/farmacologia , Flavanonas/química , Flavanonas/farmacologia , Glucosídeos/química , Glucosídeos/farmacologia , Quempferóis/química , Quempferóis/farmacologia , Quercetina/análogos & derivados , Quercetina/química , Quercetina/farmacologia , Coelhos , Espectrometria de Massas em Tandem
11.
J Water Health ; 16(5): 773-781, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30285958

RESUMO

A simple co-precipitation technique is proposed for synthesis of tin oxide (SnO2) microrods. Stannous chloride and urea were used during synthesis. X-ray powder diffraction (XRD) analysis revealed that the annealed product consists of SnO2 microrods having tetragonal unit cells, while scanning electron microscopy (SEM) analysis revealed the rod-like morphology of a synthesized product. These synthesized microrods are used as photocatalyst for the degradation of reactive black 5 (RB5). Degradation kinetics of RB5 are monitored under daylight in different concentrations of hydrogen peroxide (H2O2) and catalyst. The percentage of RB5 conversion is also calculated at various concentrations of hydrogen peroxide and catalyst which demonstrate that RB5 shows high catalytic degradation at high concentrations of hydrogen peroxide and catalyst.


Assuntos
Peróxido de Hidrogênio , Naftalenossulfonatos/química , Processos Fotoquímicos , Compostos de Estanho/química , Catálise , Modelos Químicos , Difração de Raios X
12.
Microbiol Immunol ; 62(4): 211-220, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29405384

RESUMO

The aim of the current investigation was to determine the antibacterial and antibiofilm potential of MgO nanoparticles (NPs) against antibiotic-resistant clinical strains of bacteria. MgO NPs were synthesized by a wet chemical method and further characterized by scanning electron microscopy and energy dispersive X-ray. Antibacterial activity was determined by broth microdilution and agar diffusion methods. The Bradford method was used to assess cellular protein leakage as a result of loss of membrane integrity. Microtiter plate assay following crystal violet staining was employed to determine the effect of MgO NPs on biofilm formation and removal of established biofilms. MIC values ranged between 125 and 500 µg/mL. Moreover, treatment with MgO NPs accelerated rate of membrane disruption, measured as a function of leakage of cellular proteins. Leakage of cellular protein content was greater among gram-negative bacteria. Cell adherence assay indicated 25.3-49.8% inhibition of bacterial attachment to plastic surfaces. According to a static biofilm method, MgO NPs reduced biofilm formation potential from 31% to 82.9% in a time-dependent manner. Moreover, NPs also significantly reduced the biomass of 48, 72, 96 and 120 hr old biofilms (P < 0.05). Cytotoxicity experiments using a neutral red assay revealed that MgO NPs are non-toxic to HeLa cells at concentrations of 15-120 µg/mL. These data provide in vitro scientific evidence that MgO NPs are effective and safe antibiofilm agents that inhibit adhesion, biofilm formation and removal of established biofilms of multidrug-resistant bacteria.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Óxido de Magnésio/farmacologia , Nanopartículas/química , Biofilmes/crescimento & desenvolvimento , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HeLa/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Fatores de Tempo
13.
RSC Adv ; 8(64): 36647-36661, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-35558941

RESUMO

In the present research, the degradation and decolorization of Reactive Black 5 synthetic dye at 30 ppm concentration under sun irradiation in the presence of a newly synthesized graphene based cobalt tin oxide nanocomposite were investigated. These nanoparticles were synthesized by a simple hydrothermal approach using precursor chloride salt i.e., stannous chloride and cobalt chloride and then adsorbed on the surface of RGO by a solvothermal process by changing the condition. The newly synthesized product was subjected to various instrumentation to study the morphology and other properties. X-ray powder diffraction analysis (XRD) explained the structural composition and various parameters of the product, which were further verified by Vesta software. The surface morphology of the product was analyzed by scanning electron microscopy (SEM) and it was observed that the size of each cube was approximately 5-10 µm from every face of the cube. Transmission electron microscopy (TEM) explained that the nanoparticles were within the range of 100-250 nm. These synthesized nanocubes were used in one more application, which was the investigation of the fuel efficiency in the presence of different concentrations of newly synthesized nanocomposites as a catalyst. The efficiency of kerosene oil was investigated by studying different parameters: the flash point, fire point, specific gravity, cloud point, pour point, and calorific value at increasing dosages of catalyst (0, 30, 60 and 90 ppm). It was observed that the values of these parameters changed significantly by changing the concentration of the catalyst dosage. The effect of the nanoparticles on the degradation of the RB 5 azo dye showed the highest removal percentage at the largest value of catalyst dosage, which was 0.70 mg ml-1 with the highest value of 3 ml of hydrogen peroxide.

14.
Chem Cent J ; 11(1): 49, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29086833

RESUMO

Morphologically controlled synthesis of ferric oxide nano/micro particles has been carried out by using solvothermal route. Structural characterization displays that the predominant morphologies are porous hollow spheres, microspheres, micro rectangular platelets, octahedral and irregular shaped particles. It is also observed that solvent has significant effect on morphology such as shape and size of the particles. All the morphologies obtained by using different solvents are nearly uniform with narrow size distribution range. The values of full width at half maxima (FWHM) of all the products were calculated to compare their size distribution. The FWHM value varies with size of the particles for example small size particles show polydispersity whereas large size particles have shown monodispersity. The size of particles increases with decrease in polarity of the solvent whereas their shape changes from spherical to rectangular/irregular with decrease in polarity of the solvent. The catalytic activities of all the products were investigated for both dry and wet processes such as thermal decomposition of ammonium per chlorate (AP) and reduction of 4-nitrophenol in aqueous media. The results indicate that each product has a tendency to act as a catalyst. The porous hollow spheres decrease the thermal decomposition temperature of AP by 140 °C and octahedral Fe3O4 particles decrease the decomposition temperature by 30 °C. The value of apparent rate constant (kapp) of reduction of 4-NP has also been calculated.

15.
Springerplus ; 5(1): 1493, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27652066

RESUMO

This paper is concerned with the modeling of engineering images by the fractal properties of 6-point binary interpolating scheme. Association between the fractal behavior of the limit curve/surface and the parameter is obtained. The relationship between the subdivision parameter and the fractal dimension of the limit fractal curve of subdivision fractal is also presented. Numerical examples and visual demonstrations show that 6-point scheme is good choice for the generation of fractals for the modeling of fractal antennas, bearings, garari's and rock etc.

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