chemistry (all)

A command layer for anisotropic plasmonic photo-thermal effects in liquid crystal

Photo-anisotropic properties of a particular command layer for Liquid Crystals (LCs), based on azo-benzene material, are exploited to control the photo-thermal response of a single layer of homogeneously and uniformly distributed Au nanoparticles, immobilised on a glass substrate. Experiments demonstrate that the intrinsic anisotropy of materials can influence the photo-thermal response of plasmonic systems. Indeed, the resonant absorption of radiation by plasmonic subunits is followed by a noticeable increase of their temperature.

Automated chemical kinetic mechanism simplification with minimal user expertise

An improved algorithm to generate skeletal mechanisms from the original detailed chemical kinetic mechanisms is proposed. The new algorithm builds on the computational singular perturbation (CSP) framework, by adding an additional layer of automation based on the tangential stretching rate (TSR) and the species’ participation index to TSR. The main advantage of the new approach is that it does not require the specification of a set of target species.

Investigation of the turbulent flame structure and topology at different Karlovitz numbers using the tangential stretching rate index

Turbulent premixed flames at high Karlovitz numbers exhibit highly complex structures in different reactive scalar fields to the extent that the definition of the flame front in an unambiguous manner is not straightforward. This poses a significant challenge in characterizing the observable turbulent flame behaviour such as the flame surface density, turbulent burning velocity, and so on. Turbulent premixed flames are reactive flows involving physical and chemical processes interacting over a wide range of time scales.

Vapor nucleation paths in lyophobic nanopores

Abstract.: In recent years, technologies revolving around the use of lyophobic nanopores gained considerable attention in both fundamental and applied research. Owing to the enormous internal surface area, heterogeneous lyophobic systems (HLS), constituted by a nanoporous lyophobic material and a non-wetting liquid, are promising candidates for the efficient storage or dissipation of mechanical energy.

Cryo-EM structure of the human ferritin–transferrin receptor 1 complex

Human transferrin receptor 1 (CD71) guarantees iron supply by endocytosis upon binding of iron-loaded transferrin and ferritin. Arenaviruses and the malaria parasite exploit CD71 for cell invasion and epitopes on CD71 for interaction with transferrin and pathogenic hosts were identified. Here, we provide the molecular basis of the CD71 ectodomain-human ferritin interaction by determining the 3.9 Å resolution single-particle cryo-electron microscopy structure of their complex and by validating our structural findings in a cellular context.

Seagrasses as sources of mosquito Nano-Larvicides? Toxicity and uptake of Halodule uninervis-biofabricated silver nanoparticles in Dengue and Zika Virus vector Aedes aegypti

Mosquitoes (Diptera: Culicidae) act as vectors for devastating pathogens and parasites. Zika virus, an Aedes mosquito-borne flavivirus, is becoming a worldwide public health concern following its suspected association with over 4000 recent cases of microcephaly in the infants of some women who were pregnant when they contracted the disease. There are no specific treatments for Zika virus, thus the eco-friendly and effective control of mosquito vectors is crucial.

Nanofabrication of graphene quantum dots with high toxicity against malaria mosquitoes, Plasmodium falciparum and MCF-7 cancer cells. Impact on predation of non-target tadpoles, odonate nymphs and mosquito fishes

Recently, it has been highlighted an overlooked connection between the biting activity of Anopheles mosquitoes and the spread of cancer. The excellent physico-chemical properties of graphene quantum dots (GQDs) make them a suitable candidate for biomedical applications. We focused on the toxicity of GQDs against Plasmodium falciparum and its vector Anopheles stephensi, and their impact on predation of non-target mosquito predators. Biophysical methods, including UV–vis, photoluminescence, FTIR and Raman spectroscopy, XRD analysis and TEM, confirmed the effective GQD nanosynthesis.

Mangrove helps. Sonneratia alba-synthesized silver nanoparticles magnify guppy fish predation against Aedes aegypti young instars and down-regulate the expression of envelope (E) gene in dengue virus (serotype DEN-2)

The control of dengue vectors with effective tools is crucial. Here, we fabricated silver nanoparticles (AgNP) using a cheap method relying to a mangrove extract (Sonneratia alba) as a reducing and stabilizing agent. AgNP were characterized by UV–vis spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction. LC50of S. alba extract against Aedes aegypti ranged from 192.03 ppm (larva I) to 353.36 ppm (pupa). LC50of AgNP ranged from 3.15 (I) to 13.61 ppm (pupa).

Mangrove-mediated green synthesis of silver nanoparticles with high HIV-1 reverse transcriptase inhibitory potential

Nowadays, the interactions of metal nanoparticles with microorganisms and parasites of public health importance receive increasing attention due to their functional versatility and multipurpose effectiveness. In this research, green biosynthesis of antiviral silver nanomaterials was achieved allowing the reduction of Ag+ions by the aqueous leaf extract of mangrove Rhizophora lamarckii.

Aegiceras corniculatum-mediated green synthesis of silver nanoparticles. Biophysical characterization and cytotoxicity on vero cells

Nowadays, silver nanoparticles receive increasing attention in nanomedicine, due to their characteristics which allow numerous biological applications. In this study, a biofabrication protocol was formulated to synthesize silver nanoparticles using a mangrove extract of Aegiceras corniculatum. The bio-physical characterization of mangrove-fabricated silver nanoparticles were carried out using UV–vis spectrophotometry, FTIR spectroscopy, XRD analysis and HRTEM.

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