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161.
The aim of this investigation was the surface functionalization of industrial ceramic tiles by sol‐gel technique to improve at the same time the cleanability and the antibacterial activity of surfaces. This objective was pursued through the design and preparation of nanostructured titania‐silver coating that was deposited on glazed, unglazed, and polished tiles by air‐brushing. The obtained results showed that the applied coatings are transparent, show a good adhesion, and a remarkable antibacterial activity under the tested conditions. The surface photocatalicity was optimized with the higher thermal treatments (200°C) even if photodegradation process is clearly affected by the sample surface roughness.  相似文献   
162.
Several studies in recent times have linked gut microbiome (GM) diversity to the pathogenesis of cancer and its role in disease progression through immune response, inflammation and metabolism modulation. This study focused on the use of network analysis and weighted gene co-expression network analysis (WGCNA) to identify the biological interaction between the gut ecosystem and its metabolites that could impact the immunotherapy response in non-small cell lung cancer (NSCLC) patients undergoing second-line treatment with anti-PD1. Metabolomic data were merged with operational taxonomic units (OTUs) from 16S RNA-targeted metagenomics and classified by chemometric models. The traits considered for the analyses were: (i) condition: disease or control (CTRLs), and (ii) treatment: responder (R) or non-responder (NR). Network analysis indicated that indole and its derivatives, aldehydes and alcohols could play a signaling role in GM functionality. WGCNA generated, instead, strong correlations between short-chain fatty acids (SCFAs) and a healthy GM. Furthermore, commensal bacteria such as Akkermansia muciniphila, Rikenellaceae, Bacteroides, Peptostreptococcaceae, Mogibacteriaceae and Clostridiaceae were found to be more abundant in CTRLs than in NSCLC patients. Our preliminary study demonstrates that the discovery of microbiota-linked biomarkers could provide an indication on the road towards personalized management of NSCLC patients.  相似文献   
163.
The aim of this investigation was the evaluation of the durability of photocatalytic sol–gel coating deposited on industrial ceramic tiles. In particular, the effect of substrate roughness on photocatalytic performance before and after different aging tests was determined. The results showed that the photodegradation process was clearly affected by the surface roughness of the substrate. In particular, the smoother surface had a higher photocatalytic activity, faster hydrophilicity but a lower durability to abrasion with respect to the matt surface.  相似文献   
164.
The deformation of wood is analyzed using the finite element method to quantify the phenomena in wood cells and cell walls. The deformation curves of computed microstructures are compared to experimental observations in two different loading cases: compression and combination of shear and compression. Simulated and experimental shapes of deformation curves match qualitatively and the deformation shapes exhibit a similar response to change in the loading mode. We quantify the intra-cell-wall stresses to understand the effects of the different layers during the deformation. The results benefit the development of energy efficient mechanical and chemo-mechanical pulping processes for pulp, board, and composite manufacture. In addition, the aspects of cell deformation can be exploited to dismantle the wood to accelerate chemical reactions in biorefinery.  相似文献   
165.
We consider the problem of localizing the source of a diffusion process. The source is supposed to be isotropic, and several sensors, equipped on a vehicle moving without position information, provide pointwise measures of the quantity being emitted. The solution we propose is based on computing the gradient–and higher-order derivatives such as the Hessian–from Poisson integrals: in opposition to other solutions previously proposed, this computation does neither require specific knowledge of the solution of the diffusion process, nor the use of probing signals, but only exploits properties of the PDE describing the diffusion process. The theoretical results are illustrated by simulations.  相似文献   
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Active and passive mixers, including a considerable variety of micro-devices, are nowadays widely used for the production of nanoparticles. Polymer nanoparticles for controlled drug delivery applications are investigated in this work with two specific objectives. The first one is to experimentally quantify the efficiency of confined impinging jets reactors and Tee-mixers in the production of nanoparticles constituted by two polymers: poly-?-caprolactone and poly(methoxypolyethyleneglycolcyanoacrylate-co-hexadecylcyanoacrylate). The second objective is the development of a simple and reliable mathematical model to be used for the design, optimization and scale up of mixers for polymer nanoparticle production. Although the behaviour of the polymers investigated is quite different, it is possible to conclude that confined impinging jets reactors are more efficient than Tee-mixers, in converting the pressure drop into turbulent kinetic energy and as a consequence in producing smaller particles. The very simple modelling approach proposed here (based on the evaluation of the mixing time) seems to be able to correlate well experimental data obtained under different operating conditions, independently on the type of device used. Moreover, in the case of poly-?-caprolactone it was also possible to successfully quantify the particle formation time with a simple power law, further exploiting the model.  相似文献   
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Chirality emergence in biological systems is common but the chiral expression from the molecular to macroscopic level in water-based systems is poorly understood. Among water-based systems, chromonic liquid crystals have recently received a lot of attention due to the spontaneous chirality they show when confined in curved geometries. Confinement of chiral-induced chromonics is not trivial since they are three component systems whose time stability is a delicate thermodynamic balance. In this work, a well-defined periodic Frank–Pryce texture, typical of chiral thermotropic liquid crystals, is observed in microspheres of a chiral induced chromonic embedded in a poly(dimethylsiloxane) matrix. This texture slowly degrades in time and a possible mechanism behind the degradation process is suggested via X-ray diffraction and atomic force microscopy measurements on thin chromonic films. To stabilize this texture and to control the structure periodicity, cations are added to the three components system in an attempt to tune the non-covalent interactions between molecules and supramolecular stacks. The study of the effects of this addition allows for better insight into the molecular interactions that occur in the chiral induced mesophase. This is a crucial point in view of possible biocompatible technological applications.  相似文献   
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