This research article deals with the propagation of plane waves in a rotating magneto-thermoelastic half-space with diffusion in the context of Lord–Shulman theory of thermoelasticity. The governing ...equations are formulated for a specialized plane and solved to obtain the velocity equation, which indicates the existence of four coupled plane waves. The wave velocities are computed for a particular medium, and the effect of the diffusion parameter is shown graphically on these waves. Impedance boundary conditions are applied to study the reflection of plane waves from the stress-free and thermally insulated/isothermal surface. Reflection coefficients and energy ratios of the reflected waves are also obtained, and the variations of reflection coefficients and energy ratios against the angle of incidence are shown graphically.
Bovine mastitis caused by multidrug resistant Staphylococcus aureus is a huge problem reported worldwide, resulting in prolonged antibiotic treatment and death of livestock. The current study is ...focused on surveillance of antibiotic susceptibility along with genotypic and phenotypic characterization of the pathogenic S. aureus strains causing mastitis in India. One hundred and sixty seven milk samples were collected from mastitis-affected cows from different farms in India resulting in thirty nine isolated S. aureus strains. Antibiotic sensitivity profiling revealed the majority of the strains (n = 24) to be multidrug resistant and eleven strains showed reduced susceptibility to vancomycin (MICs = 2μg/ml). All strains were oxacillin sensitive, but 19 strains were positive for the mecA gene, which revealed the occurrence of oxacillin susceptible mecA positive strains (OS-MRSA) for the first time from India. Additionally, 32 strains were positive for the pvl gene, a virulence determinant; of these 17 were also OS-MRSA strains. Molecular characterization based on multilocus sequence typing (MLST), spa typing, agr typing and SCCmec classification revealed strains belonging to different groups. Moreover, strains showed spa types (t2526, t9602) and MLST sequence types, ST-72, ST-88 and ST-239 which have been earlier reported in human infections. The prevalence of OS-MRSA strains indicates the importance of including both the genetic and phenotypic tests in characterizing S. aureus strains. Increased genotypic variability with strain related to human infections and pvl positive isolates indicates a worrisome situation with the possibility of bilateral transfer.
Fluorescence lifetime (FLT) multiplexing and multispectral imaging (MSI) are both frequently employed for
and
biological studies.
applications of MSI for deep seated fluorophores require ...consideration of diffusive light propagation in biological tissue. We have previously shown that a well-known redshift of fluorescence spectra in diffusive medium induces a fluorophore cross-talk, which cannot be accounted for even with known optical properties of the medium. In contrast, FLT measurements remain largely unaffected by light propagation in tissue, enabling zero cross-talk and accurate relative quantification. While a fully quantitative estimation of fluorophore concentrations requires depth resolved tomographic imaging, this is often not possible due to the difficulty of estimating tissue optical properties and modelling light propagation in complex tissue geometries. Here, we experimentally investigate the performance of planar (non-tomographic) MSI and FLT multiplexing for the quantitative recovery of multiple near-infrared fluorophores embedded in 4-8 mm thick tissue. We show that FLT multiplexing provides a superior quantification accuracy (error < 10%) compared to MSI (error = 20-107%) in tissue. The error rates for MSI increased with tissue thickness and can be directly attributed to the spectral redshift induced cross-talk between emission spectra. Our data indicate that planar FLT multiplexing can provide high quantification accuracy in thick biological tissue without a need for optical property estimation, thereby offering an important validation tool for rapid quantification of fluorophore concentrations in bulk tissue.
Since 2006, ceria is used as a redox reactive material for production of H2, CO, and syngas via a two-step solar driven thermochemical H2O/CO2 splitting cycle. Different forms of phase pure ceria ...were studied over a wide range of temperatures and oxygen partial pressures. To increase the redox reactivity and long-term stability, the effects of incorporation of different dopants in to the ceria fluorite structure (in varying proportions) were studied in detail. A variety of solar reactors, loaded with ceria based ceramics, were designed and developed to investigate the performance of these materials towards thermal reduction and H2O/CO2 splitting reactions. The thermodynamics and reaction kinetics of ceria based solar thermochemical H2O/CO2 splitting cycles were also explored heavily. This paper presents a detailed chronological insight into the development of ceria-based oxides as reactive materials for solar fuel production via thermochemical redox H2O/CO2 splitting cycles.
•The redox reactivity of the phase pure ceria can be improved by incorporating suitable dopants.•The current studies are directing towards utilization of reticulated porous ceria ceramics.•To improve the fuel yield, mass and heat transfer related to the redox reactions needs to be improved significantly.•Pilot scale design and development of ceria based solar reactors is essential to move towards commercialization.
► One step process for synthesizing pure and mixed phase TiO2 nanoparticles. ► The crystallite size of prepared TiO2 at different temperature is in the range of 19–68nm. ► The tensile strain has been ...observed below 600°C and converted into compressive strain at 700°C. ► Photoluminescence spectroscopy (PL) exhibits the change in PL intensity with phase change. ► Different trends have been observed in emission edges.
Pure and mixed phase TiO2 have been prepared by sol–gel method; calcinated at four different temperatures. The influence of calcination temperature on crystallite size, morphology, band gap and luminescence properties of resultant material have been investigated. Different trends were observed in the phase transformation, particle growth, shift in energy band gap and in luminescence with the change in tensile strain to compressive strain of the prepared TiO2 nanomaterial. X-ray diffraction (XRD) showed that prepared nanocrystals have pure anatase and anatase-rutile mixed structures. The prepared samples having crystallite size between 19nm to 68nm were observed at different calcination temperatures. Williamson-Hall plot results indicate the presence of tensile strain at 400, 500 and 600°C while compressive strain at 700°C. Scanning electron microscopy (SEM) shows that the particles are non-uniform. Ultraviolet-Visible spectroscopy (UV-Vis) is used to calculate the energy band gap of materials and it has been observed that the band gap decreases with increase in temperature. Fourier transform infrared spectroscopy (FTIR) describes local environment around TiO2 nanoparticles. Photoluminescence spectroscopy (PL) exhibits the change in PL intensity with phase change and different trends have been observed in emission edges.
5-HT
a G-protein coupled receptor, is widely expressed in the human body, including in the gastrointestinal tract, platelets and the nervous system. It mediates various functions, for e.g. learning, ...memory, mood regulation, platelet aggregation and vasoconstriction, but its involvement in cell-adhesion remains largely unknown. Here we report a novel role for 5-HT
in cell-matrix adhesion.In HEK293 cells, which are loosely adherent, expression and stimulation of human or rat 5-HT
receptor by agonists such as serotonin or 2,5-dimethoxy-4-iodoamphetamine (DOI) led to a significant increase in adhesion, while inhibition of 5-HT
by antipsychotics, such as risperidone, olanzapine or chlorpromazine prevented it. 5-HT
activation gave rise to stress fibers in these cells and was also required for their maintenance. Mechanistically, the 5-HT
-mediated adhesion was mediated by downstream PKC and Rho signaling. Since 5-HT
is associated with many disorders such as dementia, depression and schizophrenia, its role in cell-matrix adhesion could have implications for neural circuits.
The choice of suitable inoculants in the grain refinement process and subsequent enhancement of the characteristics of the composites developed is an important materials research topic, having wide ...scope. In this regard, the present work is aimed at finding the appropriate composition and size of fly ash as inoculants for grain refinement of the aluminum AA 5083 composites. Fly ash particles, which are by products of the combustion process in thermal power plants, contributing to the large-scale pollution and landfills can be effectively utilized as inoculants and interatomic lubricants in the composite matrix–reinforcement subspaces synthesized in the inert atmosphere using ultrasonic assisted stir casting setup. Thus, the work involves the study of the influence of percentage and size of the fly ash dispersions on the tensile and impact strength characteristics of the aluminum AA 5083/7.5SiC composites. The C type of fly ash with the particle size in the series of 40–75 µm, 76–100 µm, and 101–125 µm and weight % in the series of 0.5, 1, 1.5, 2, and 2.5 are selected for the work. The influence of fly ash as distinct material inoculants for the grain refinement has worked out well with the increase in the ultimate tensile strength, yield strength, and impact strength of the composites, with the fly ash as material inoculants up to 2 wt. % beyond which the tensile and impact characteristics decrease due to the micro coring and segregation. This is evident from the microstructural observations for the composite specimens. Moreover, the role of fly ash as material inoculants is distinctly identified with the X-Ray Diffraction (XRD) for the phase and grain growth epitaxy and the Energy Dispersive Spectroscopy (EDS) for analyzing the characteristic X-Rays of the fly ash particles as inoculant agents in the energy spectrum.
Underwater communication (UWC) is widely used in coastal surveillance and early warning systems. Precise channel estimation is vital for efficient and reliable UWC. The sparse direct‐adaptive ...filtering algorithms have become popular in UWC. Herein, we present an improved adaptive convex‐combination method for the identification of sparse structures using a reweighted normalized least‐mean‐square (RNLMS) algorithm. Moreover, to make RNLMS algorithm independent of the reweighted
l1‐norm parameter, a modified sparsity‐aware adaptive zero‐attracting RNLMS (AZA‐RNLMS) algorithm is introduced to ensure accurate modeling. In addition, we present a quantitative analysis of this algorithm to evaluate the convergence speed and accuracy. Furthermore, we derive an excess mean‐square‐error expression that proves that the AZA‐RNLMS algorithm performs better for the harsh underwater channel. The measured data from the experimental channel of SPACE08 is used for simulation, and results are presented to verify the performance of the proposed algorithm. The simulation results confirm that the proposed algorithm for underwater channel estimation performs better than the earlier schemes.
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