In this study, a numerical examination of the significance of rotation and changeable gravitational field on the start of nanofluid convective movement in an anisotropic porous medium layer is shown. ...A model that accounts for the impact of Brownian diffusion and thermophoresis is used for nanofluid, while Darcy’s law is taken for the porous medium. The porous layer is subjected to uniform rotation and changeable downward gravitational field which fluctuates with the height from the layer by linearly or parabolic. The higher-order Galerkin technique is applied to obtain the numerical solutions. The outcomes demonstrate that the rotation parameter TD, the thermal anisotropy parameterh and the gravity variation parameter λ slow the beginning of convective motion, whereas the mechanical anisotropy parameter ξ, the nanoparticle Rayleigh-Darcy number Rnp, the modified diffusivity ratio NAnf and the modified nanofluid Lewis number Lenf quick the start of convective motion. For instance, by rising the gravity variation parameterfrom zero to 1.4, the critical nanofluid thermal Rayleigh-Darcy number Rnf,c and the critical wave numberboost maximum around 133% and 7%, respectively for linear variation of the gravity field, while it were 47% and 2.8% for parabolic variation of the gravity field. It is also observed that the system is more unstable for the parabolic variation of the gravity field.
In this analysis, the collective impact of external electric field and internal heat generation on the onset of thermal convection of Jeffery fluid in a porous matrix is investigated analytically. ...Utilising linear stability hypothesis reliant on the normal mode process, a dispersion relation is derived and this dispersion relation is investigated for stationary and oscillatory styles of convective activities. The results reveal that the stability of the system diminishes by increasing the Jeffery parameter
λ
, the electric field parameter
R
E
and the internal heating parameter
S
H
. It is also shown that the oscillatory style of convective movement has not been feasible for the problem.
Aims
UK-DNDC model was modified to (1) enhance the estimates of soil temperature and N
2
O emissions in Denitrification Decomposition (DNDC) model by considering snow melt and frozen and unfrozen ...conditions along with the impacts of water flux density, thermal diffusivity, crop-canopy, snowmelt routine and snow-depth on N
2
O emission and (2) validate the modified DNDC model against measured data from five experimental cropping sites located in the west Canada.
Methods
Heat transfer processes and snowmelt routine of the DNDC have been modified to account for soil heat and water fluxes driven by snowmelt routine and their effects on denitrification and N
2
O emissions. The modified DNDC model was tested against the data from five sites, Canada. Then, the model was used to predict the spatial and temporal change of snowpack depth, soil temperature and N
2
O emissions.
Results
The validation results show that the modified model predicted daily soil mean temperature and daily N
2
O fluxes accurately in all seasons with very high average Pearson’s correlation coefficients at the three sites (
R
avg
= 0.91
and
0.85
for soil temperature and N
2
O emissions, respectively).
Conclusions
The modelled N
2
O emissions were sensitive to snowmelt and freeze-thaw cycle in the cold climate region while the modelled soil temperature was sensitive to water flux. This provides a tool for N
2
O estimate in Canada and should also be appropriate for utilize in the similar cold climate regions.
Melasma is a hypermelanotic skin disorder characterized by dark brown macules of symmetrical sizes and shapes that develop over time. Apart from the multiple etiological factors for melasma, such as ...hormonal imbalances, thyroid dysfunction, drugs, and contraceptive pills, a new and significant cause has been discovered: the effect of oxidative stress. Oxidative stress is the result of disequilibrium between reactive oxygen species and antioxidants in the cells. It is a key element that can cause skin hypopigmentation or hyperpigmentation. The physiological significance of reactive oxygen species and its function in skin health are addressed in this study. The development process and pathophysiology of reactive oxygen species with melasma disorder are also highlighted and the advantages of integrating antioxidants in clinical and experimental environments are discussed.
In this review article, we present the updated evidence of therapeutic applications of fucoidan (a seaweed polysaccharide) and its novel potential to treat infectious diseases such as coronavirus ...disease (COVID-19). Because of their many biological activities, seaweeds have been identified as a rich and useful source of bioactive chemicals. Sulfated polysaccharides from the sea are considered a source of physiologically active chemicals that might be used in medication development. Antitumor, antiviral, antioxidant, antibacterial, anticoagulant, and immune-inflammatory properties have all been described for these compounds. By interfering at various phases of viral infection, marine sulfated polysaccharide has a virucidal effect. As a result, it opens the door to the development of antiviral treatments. Virus entry into host cells is an initial process, avoiding this type of entry makes any precautionary measure effective. The inhibitory action of certain marine sulfated polysaccharides against coronavirus was tested, and fucoidan, iota-carrageenan, and sea cucumber sulfated polysaccharides all showed a substantial antiviral impact. Fucoidan is one of the useful sulfated polysaccharides that has been widely studied and explored in various research. There are different sources of fucoidans, which have been used in the treatment of viral infection. Additionally, we highlight the mechanism of action of fuocidan against COVID-19. Hence, we could suggest that COVID-19 might be prevented and treated using these sulfated polysaccharides. This review thus highlights ample evidence to support the hypothesis that a large number of drugs have been developed from powerful compounds isolated from marine seaweeds.
The instability of an interface formed at the boundary of a circular cylindrical cavity is examined through an irrotational theory of viscous fluids. The cavity is assumed to be an infinite circular ...cylinder and the flow is considered to be two-dimensional. The cavity is filled with the Newtonian viscous fluid while the fluid outside the cavity is taken as Newtonian nanofluid. The normal mode procedure is employed and the growth rate parameter is calculated. The quadratic relationship in growth rate is achieved and for larger modes, it reduces to the case of the planar interface. The variety of nanofluids’ physical parameters is studied on the instability of the interface. The density of nanofluid makes the interface more unstable while nanofluid’s viscosity has stabilizing nature. The nanofluid with larger radius nanoparticles forms a more unstable interface than the smaller sized nanoparticles.
Nanotechnology is the science of nano-sized particles/structures (~100 nm) having a high surface-to-volume ratio that can modulate the physical, chemical and biological properties of the chemical ...compositions. In last few decades, nanoscience has attracted the attention of the scientific community worldwide due to its potential uses in the pharmacy, medical diagnostics and disease treatment, energy, electronics, agriculture, chemical and space industries. The properties of nanoparticles (NPs) are size and shape dependent. These characteristic features of nanoparticles can be explored for various other applications such as computer transistors, chemical sensors, electrometers, memory schemes, reusable catalysts, biosensing, antimicrobial activity, nanocomposites, medical imaging, tumor detection and drug delivery. Therefore, synthesizing nanoparticles of desired size, structure, monodispersity and morphology is crucial for the aforementioned applications. Recent advancements in nanotechnology aim at the synthesis of nanoparticles/materials using reliable, innoxious and novel ecofriendly techniques. In contrast to the traditional methods, the biosynthesis of nanoparticles of a desired nature and structure using the microbial machinery is not only quicker and safer but more environmentally friendly. Various microbes, including bacteria, actinobacteria, fungi, yeast, microalgae and viruses, have recently been explored for the synthesis of metal, metal oxide and other important NPs through intracellular and extracellular processes. Some bacteria and microalgae possess specific potential to fabricate distinctive nanomaterials such as exopolysaccharides, nanocellulose, nanoplates and nanowires. Moreover, their ability to synthesize nanoparticles can be enhanced using genetic engineering approaches. Thus, the use of microorganisms for synthesis of nanoparticles is unique and has a promising future. The present review provides explicit information on different strategies for the synthesis of nanoparticles using microbial cells; their applications in bioremediation, agriculture, medicine and diagnostics; and their future prospects.
Traditional medicines are nature's gift and our native heritage, which play a vital role in maintaining a disease-free life.
.
(family: Asteraceae), popularly known as "Kubsha" or "Russian wormwood", ...is a highly enriched folklore medicine with wound- healing, antiphlogistic, antifebrile, antifeedant, anti-helminthic, antimicrobial, antiviral, antitumor, and antiproliferative potential attributed to the presence of various volatile and non-volatile secondary metabolites. A systematic and extensive review of the literature on
was carried out via the Web of Science, PubMed, INMEDPLAN, EMBASE, Google Scholar, and NCBI, as well as from several websites. The highly relevant literature contained in 109 references was selected for further inclusion in this review. A total of 202 bioactive compounds belonging to different chemical classes such as terpenoids, coumarins, flavonoids, alkaloids, acetylenes, tannins, carotenoids, and sterols have been reported in
, which are responsible for different pharmacological activities. The chemical structures obtained from the PubChem and Chem Spider databases were redrawn using the software Chem Draw
version 8.0. This review paper summarizes the distribution, botanical description, phytochemistry, pharmacological activities, and conservation of
which will assist scientists for further investigation. Extensive studies on the active constituents, pharmaceutical standardization, mode of action, and sustainable conservation of
are needed to further explore its wound-healing and allied medicinal properties.
Alzheimer’s disease (AD) is a progressive neurodegenerative disease that affects most people worldwide. AD is a complex central nervous system disorder. Several drugs have been designed to cure AD, ...but with low success rates. Because the blood–brain and blood–cerebrospinal fluid barriers are two barriers that protect the central nervous system, their presence has severely restricted the efficacy of many treatments that have been studied for AD diagnosis and/or therapy. The use of nanoparticles for the diagnosis and treatment of AD is the focus of an established and rapidly developing field of nanomedicine. Recent developments in nanomedicine have made it possible to effectively transport drugs to the brain. However, numerous obstacles remain to the successful use of nanomedicines in clinical settings for AD treatment. Furthermore, given the rapid advancement in nanomedicine therapeutics, better outcomes for patients with AD can be anticipated. This article provides an overview of recent developments in nanomedicine using different types of nanoparticles for the management and treatment of AD.
PDF
