Lanthanum titanate (La
2
Ti
2
O
7
) with perovskite-like layered structure is a candidate material for high temperature sensor application due to its high curie temperature (
T
c
= 1461 °C) and ...linearity of temperature vs. electrical resistance. La
2
Ti
2
O
7
(LTO) was synthesized by solid state reaction using constituent powders at 1250 °C for 2 h. The LTO samples prepared in the form of circular pellets were sintered in temperature ranges (1350 to 1400 °C for 2 h). The sintered density was found highest at 1400 °C for LTO samples (> 97.24% Th.). Moreover, the sintered LTO samples were characterized for their ferroelectric properties as well as DC electrical resistivity (
ρ
) measured in the temperature range of 100 to 900 °C. The electrical resistivity was decreased from 10
13
to 10
6
Ω cm linearly with the increase in temperature from 100 to 900 °C. Hence, LTO is a promising sensor material for high temperature applications.
Machine learning (ML)-based techniques have found significant impact in many fields of engineering and sciences, where data-sets are available from experiments and high-fidelity numerical ...simulations. Those data-sets are generally utilised in a machine learning model to extract information about the underlying physics and derive functional relationships mapping input variables to target quantities of interest. Commonplace machine learning algorithms utilised in scientific machine learning (SciML) include neural networks, support vector machines, regression trees, random forests, etc. The focus of this article is to review the applications of ML in naval architecture, ocean and marine engineering problems; and identify priority directions of research. We discuss the applications of machine learning algorithms for different problems such as wave height prediction, calculation of wind loads on ships, damage detection of offshore platforms, calculation of ship-added resistance and various other applications in coastal and marine environments. The details of the data-sets including the source of data-sets utilised in the ML model development are included. The features used as the inputs to the ML models are presented in detail and finally, the methods employed in optimisation of the ML models were also discussed. Based on this comprehensive analysis, we point out future directions of research that may be fruitful for the application of ML to ocean and marine engineering problems.
The ability of self-functionalized biogenic GNPs towards highly selective colorimetric detection of rare earth element cerium is being reported for the first time. GNPs underwent rapid aggregation on ...addition of cerium indicated by red shift of SPR peak followed by complete precipitation. Hereby, this concept of co-ordination of cerium ions onto the GNP surface has been utilized for detection of cerium. The remarkable capacity of GNPs to sensitively detect Ce without proves beneficial compared to previous reports of colorimetric sensing. MDL was 15 and 35 ppm by DLS and UV-vis spectroscopy respectively, suggesting DLS to be highly sensitive and a practical alternative in ultrasensitive detection studies. The sensing system showed a good linear fit favouring feasible detection of cerium in range of 2-50 ppm. Similar studies further showed the superior selectivity of biogenic GNPs compared to chemically synthesized counterparts. The sensing system favours on-site analysis as it overcomes need of complex instrumentation, lengthy protocols and surface modification of GNP.
Multiple sclerosis (MS) is an inflammatory disease characterized by myelin loss. While therapies exist to slow MS progression, no treatment currently exists for remyelination. Remyelination, linked ...to reduced disability in MS, relies on microglia and monocyte-derived macrophages (MDMs). This study aims to understand the role of microglia during remyelination by lineage tracing and depleting them. Microglial lineage tracing reveals that both microglia and MDMs initially accumulate, but microglia later dominate the lesion. Microglia and MDMs engulf equal amounts of inhibitory myelin debris, but after microglial depletion, MDMs compensate by engulfing more myelin debris. Microglial depletion does, however, reduce the recruitment and proliferation of oligodendrocyte progenitor cells (OPCs) and impairs their subsequent differentiation and remyelination. These findings underscore the essential role of microglia during remyelination and offer insights for enhancing this process by understanding microglial regulation of remyelination.
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•Microglia and monocyte-derived macrophages engulf equal volumes of myelin debris•Macrophages compensate to remove myelin debris when microglia are depleted•Microglia facilitate oligodendrocyte progenitor cell proliferation•Microglia promote oligodendrocyte differentiation and remyelination
Baaklini et al. demonstrate that, after demyelination, microglia and monocyte-derived macrophages engulf equal volumes of myelin debris. They found that microglia depletion did not impact myelin debris clearance because monocyte-derived macrophages could compensate. They found that microglia did promote oligodendrocyte progenitor cell recruitment and their subsequent differentiation and remyelination.
We study the quark deconfinement phase transition in hot β-stable hadronic matter. Assuming a first order phase transition, we calculate the enthalpy per baryon of the hadron–quark phase transition. ...We calculate and compare the nucleation rate and the nucleation time due to thermal and quantum nucleation mechanisms. We compute the crossover temperature above which thermal nucleation dominates the finite temperature quantum nucleation mechanism. We next discuss the consequences for the physics of proto-neutron stars. We introduce the concept of limiting conversion temperature and critical mass Mcr for proto-hadronic stars, and we show that proto-hadronic stars with a mass M<Mcr could survive the early stages of their evolution without decaying to a quark star.
Natural products are regarded as vital key source of lead compounds for drug discovery due to their structural diversity and broad array of biological activities. Phenylpropanoid sucrose esters are ...naturally occurring compounds isolated from various plants and are structurally characterized by a sucrose core connected to one or more Ph-CH=CH-CO- moieties through an ester linkage. These compounds were extensively used in folk medicine and are found to possess many biological activities such as antitumor, antibacterial, antioxidant, antiviral, anti-inflammatory, neuro-protective and glycosidase inhibitory activities. This extensive review, which is the first of its kind on phenylpropanoid sucrose esters, aims to provide an up-to-date account of naturally occurring known phenylpropanoid sucrose esters with special focus on their sources, structures, biological and pharmacological activities.
Lead free piezo materials are becoming popular as the world is conscious about toxicity of PbO present in PZT. As a result, lot of R&D efforts are made in last two decades to find out suitable lead ...free piezo ceramics as effective as PZT. There are many lead free piezo systems explored. Among them, BZT-BCT is more promising due to its high piezoelectric coefficients. This system is well researched by modifying its structure with a large number of dopants. In this paper, an effort has been made to review the effect of various dopants on electrical properties of BCT-BZT systems.
Microglia regulate the response to injury and disease in the brain and spinal cord. In white matter diseases microglia may cause demyelination. However, how microglia respond and regulate ...demyelination is not fully understood.
To understand how microglia respond during demyelination, we fed mice cuprizone-a potent demyelinating agent-and assessed the dynamics of genetically fate-mapped microglia. We then used single-cell RNA sequencing to identify and track the microglial subpopulations that arise during demyelination. To understand how microglia contribute to the clearance of dead oligodendrocytes, we ablated microglia starting at the peak of cuprizone-induced cell death and used the viability dye acridine orange to monitor apoptotic and lytic cell morphologies after microglial ablation. Lastly, we treated serum-free primary microglial cultures to model distinct aspects of cuprizone-induced demyelination and assessed the response.
The cuprizone diet generated a robust microglial response by week 4 of the diet. Single-cell RNA sequencing at this time point revealed the presence of several cuprizone-associated microglia (CAM) clusters. These clusters expressed a transcriptomic signature indicative of cytokine regulation and reactive oxygen species production with altered lysosomal and metabolic changes consistent with ongoing phagocytosis. Using acridine orange to monitor apoptotic and lytic cell death after microglial ablation, we found that microglia preferentially phagocytose lytic carcasses. In culture, microglia exposed to lytic carcasses partially recapitulated the CAM state, suggesting that phagocytosis contributes to this distinct microglial state during cuprizone demyelination.
Microglia serve multiple roles during demyelination, yet their transcriptomic state resembles other neurodegenerative conditions. The phagocytosis of cellular debris is likely a universal cause for a common neurodegenerative microglial state.
This paper considers the effect of mass transfer on free convective flow and heat transfer of a viscous incompressible electrically conducting fluid past a vertical porous plate through a porous ...medium with time dependant permeability and oscillatory suction in presence of a transverse magnetic field and heat source. The solutions for velocity field, temperature field and concentration distribution are obtained using perturbation technique. The effects of the flow parameters such as magnetic parameter
M, Grashof number for heat and mass transfer
G
r
,
G
c
, porosity parameter
K
p
, Prandtl number
P
r
, Schmidt number
S
c
, frequency parameter
ω
and heat source parameter
S on the velocity, temperature and concentration distribution of the flow field and the skin friction, heat flux and the rate of mass transfer are studied analytically and presented with the aid of figures and tables. It is observed that the magnetic parameter and the Schmidt number retard the velocity of the flow field while the Grashof number for heat and mass transfer, the porosity parameter and the heat source parameter have accelerating effect on the velocity of the flow field at all points. Further, the Prandtl number reduces the temperature and the Schmidt number diminishes the concentration distribution of the flow field at all points. The skin friction coefficients
τ
0
and
τ
increase due to increase in
G
r
,
G
c
and
K
p
while decrease due to increase in
S
c
,
M,
ω
and
P
r
. Further, the rate of mass transfer
S
h
increases due to increase in
S
c
while an increase in
ω
results a decrease in
S
h
.
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