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711.
We report the influence of Fe3O4 nanoparticles (NPs) on porphyrins in the development of photosensitizers (PSs) for efficient photodynamic therapy (PDT) and possible post-PDT responses for inflicting cancer cell death. Except for Au, most metal-based nanomaterials are unsuitable for clinical applications. The US Food and Drug Administration and other agencies have approved Feraheme and a few other iron oxide NPs for clinical use, paving the way for novel biocompatible immunoprotective superparamagnetic iron oxide nanohybrids to be developed as nanotherapeutics. A water-soluble nanohybrid, referred to here as E-NP, comprising superparamagnetic Fe3O4 NPs functionalised with tripyridyl porphyrin PS was introduced through a rigid 4-carboxyphenyl linker. As a PDT agent, the efficacy of E-NP toward the AGS cancer cell line showed enhanced photosensitising ability as determined through in vitro photobiological assays. The cellular uptake of E-NPs by AGS cells led to apoptosis by upregulating ROS through cell-cycle arrest and loss of mitochondrial membrane potential. The subcellular localisation of the PSs in mitochondria stimulated apoptosis through upregulation of p21, a proliferation inhibitor capable of preventing tumour development. Under both PDT and non-PDT conditions, this nanohybrid can act as an anti-inflammatory agent by decreasing the production of NO and superoxide ions in murine macrophages, thus minimising collateral damage to healthy cells.  相似文献   
712.
Metal silicides and silicates belong to the silicon-based non-oxide and oxide ceramics family with exceptional properties. Silicides face fatal oxidation at low temperatures and intrinsic brittleness, whereas silicates face instability in phase at high temperatures which restricts its usage in vast engineering applications. Hence, the ceramic community introduced the concept of high entropy in metal silicides and silicates. Since 2019, high entropy silicides and silicates, a multicomponent system, have created new avenues for materials discovery and design. High entropy silicides displayed elevated properties than the traditional silicides aiming its applications in microelectronic, high-temperature oxidation resistance coatings, and structural materials. Similarly, high entropy silicates displayed improved properties than the traditional silicates making them the most promising materials for environmental and thermal barrier coating applications for hot section components in gas turbines. The review focuses on specific case studies to emphasize the latest research and developments in high entropy silicides and silicates. Synthesis approaches employed in developing high entropy silicides and silicates and their structural and microstructural outcomes are addressed. The possible application is predicted based on the overview of the properties explored to date. The review concludes with future possibilities offered by the high entropy silicides and silicates.  相似文献   
713.
Petroleum and exploration industries employ a hydrofracking process where a large volume of water (fracturing fluid) is injected and a fraction (known as flowback water) is returned to the surface. Froth flotation is a typical process employed for the primary treatment of water. In the present work, froth flotation has been used as a pretreatment method for real flowback water sourced from the petroleum and shale gas exploration industry. In the present work, a first-principle based convective mass transfer model has been developed to describe the froth flotation performance. The resultant equation was solved analytically and compared with the numerical solution, and a parametric sensitivity analysis of the process performance was also undertaken. In addition, a correlation to estimate the flotation rate constant was proposed, thereby circumventing the need to obtain a large number of cumbersome parameters experimentally. Overall, this study proposes froth flotation as an efficient primary treatment method towards the separation of dispersed oil droplets from the flowback water and the corresponding prediction of kinetics using a first-principle based transport model.  相似文献   
714.
Sub-cellular organelles play a critical role in a myriad biological phenomena. Consequently, organelle structures and functions are invariably highjacked in diverse diseases including metabolic disorders, aging, and cancer. Hence, illuminating organelle dynamics is crucial in understanding the diseased states as well as developing organelle-targeted next generation therapeutics. In this review, we outline the novel small molecules which show remarkable aggregation-induced emission (AIE) properties due to restriction in intramolecular motion (RIM). We outline the examples of small molecules developed to image organelles like mitochondria, endoplasmic reticulum (ER), Golgi, lysosomes, nucleus, cell membrane and lipid droplets. These AIEgens have tremendous potential for next-generation phototherapy.  相似文献   
715.
Manipulation of long-range order in 2D van der Waals (vdW) magnetic materials (e.g., CrI3, CrSiTe3 ,etc.), exfoliated in few-atomic layer, can be achieved via application of electric field, mechanical-constraint, interface engineering, or even by chemical substitution/doping. Usually, active surface oxidation due to the exposure in the ambient condition and hydrolysis in the presence of water/moisture causes degradation in magnetic nanosheets that, in turn, affects the nanoelectronic /spintronic device performance. Counterintuitively, the current study reveals that exposure to the air at ambient atmosphere results in advent of a stable nonlayered secondary ferromagnetic phase in the form of Cr2Te3 (TC2 ≈160 K) in the parent vdW magnetic semiconductor Cr2Ge2Te6 (TC1 ≈69 K). The coexistence of the two ferromagnetic phases in the time elapsed bulk crystal is confirmed through systematic investigation of crystal structure along with detailed dc/ac magnetic susceptibility, specific heat, and magneto-transport measurement. To capture the concurrence of the two ferromagnetic phases in a single material, Ginzburg-Landau theory with two independent order parameters (as magnetization) with a coupling term can be introduced. In contrast to the rather common poor environmental stability of the vdW magnets, the results open possibilities of finding air-stable novel materials having multiple magnetic phases.  相似文献   
716.
Parallelization strategies are presented for Virtual Quake, a numerical simulation code for earthquakes based on topologically realistic systems of interacting earthquake faults. One of the demands placed upon the simulation is the accurate reproduction of the observed earthquake statistics over three to four decades. This requires the use of a high‐resolution fault model in computations, which demands computational power that is well beyond the scope of off‐the‐shelf multi‐core CPU computers. However, the recent advances in general‐purpose graphic processing units have the potential to address this problem at moderate cost increments. A functional decomposition of Virtual Quake is performed, and opportunities for parallelization are discussed in this work. Computationally intensive modules are identified, and these are implemented on graphics processing units, significantly speeding up earthquake simulations. In the current best case scenario, a computer with six graphics processing units can simulate 500 years of fault activity in California at 1.5 km × 1.5 km element resolution in less than 1 hour, whereas a single CPU requires more than 2 days to perform the same simulation. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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