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391.
Albonetti C Martinez J Losilla NS Greco P Cavallini M Borgatti F Montecchi M Pasquali L Garcia R Biscarini F 《Nanotechnology》2008,19(43):435303
We investigate the fabrication of nanometric patterns on silicon surfaces by using the parallel-local anodic oxidation technique with soft stamps. This method yields silicon oxide nanostructures 15?nm high, namely at least five times higher than the nanostructures made with local anodic oxidation using atomic force microscopy, and thanks to the size of the stamp enables one to pattern the surface across a centimetre length scale. To implement this technique, we built a machine to bring the metallized polydimethylsiloxane stamp in contact with the silicon surface, subsequently inserted in a sealed chamber with controlled relative humidity. The oxide nanostructures are fabricated when a bias voltage of 36?V is applied between the stamp and the silicon for 2?min, with a relative humidity of 90%. The flexibility of the stamp enables a homogeneous conformal contact with the silicon surface, resulting in an excellent reproducibility of the process. Moreover, by means of two subsequent oxidations with the same stamp and just rotating the sample, we are able to fabricate complex nanostructures. Finally, a detailed study of the oxidation mechanism, also using a finite element analysis, has been performed to understand the underlying mechanism. 相似文献
392.
Vinícius de Paiva Gonalves Marta Liliana Musskopf Angeliz Rivera-Concepcion Christina Yu Sing Wai Wong Stephen A. Tuin Yizu Jiao Cristiano Susin Luís Carlos Spolidorio Patricia Almeida Miguez 《International journal of molecular sciences》2022,23(13)
This study aimed to evaluate the effects of hesperidin (HE) on in vitro osteoclastogenesis and dietary supplementation on mouse periodontal disease and femoral bone phenotype. RAW 264.7 cells were stimulated with RANKL in the presence or absence of HE (1, 100 or 500 µM) for 5 days, and evaluated by TRAP, TUNEL and Western Blot (WB) analyses. In vivo, C57BL/6 mice were given HE via oral gavage (125, 250 and 500 mg/kg) for 4 weeks. A sterile silk ligature was placed between the first and second right maxillary molars for 10 days and microcomputed tomography (μCT), histopathological and immunohistochemical evaluation were performed. Femoral bones subjected or not to dietary HE (500 mg/kg) for 6 and 12 weeks were evaluated using μCT. In vitro, HE 500 µM reduced formation of RANKL-stimulated TRAP-positive(+) multinucleated cells (500 µM) as well as c-Fos and NFATc1 protein expression (p < 0.05), markers of osteoclasts. In vivo, dietary HE 500 mg/kg increased the alveolar bone resorption in ligated teeth (p < 0.05) and resulted in a significant increase in TRAP+ cells (p < 0.05). Gingival inflammatory infiltrate was greater in the HE 500 mg/kg group even in the absence of ligature. In femurs, HE 500 mg/kg protected trabecular and cortical bone mass at 6 weeks of treatment. In conclusion, HE impaired in vitro osteoclastogenesis, but on the contrary, oral administration of a high concentration of dietary HE increased osteoclast numbers and promoted inflammation-induced alveolar bone loss. However, HE at 500 mg/kg can promote a bone-sparing effect on skeletal bone under physiological conditions. 相似文献
393.
Cristiano Carlomagno Giorgio Speranza Pranesh Aswath Gian Domenico Sorarù Claudio Migliaresi Devid Maniglio 《Journal of the European Ceramic Society》2018,38(4):1320-1326
Little has been published so far on the fabrication of porous ceramic films by using the Breath Figure method. In this work we explored the Breath Figure method to obtain ceramics with patterned surfaces. A UV cross-linkable polysiloxane was used to produce Breath Figures with tunable pore size. Pores formation, in terms of size and distribution on the polysiloxane films, were studied as a function of the concentration of the starting solution and time before UV irradiation. The polymeric breath figures were then pyrolyzed in controlled atmosphere to obtain, through the polymer-derived ceramic, PDCs, route the corresponding ceramic preserving the original porous surface. Pyrolysis under different gases, in particular air, nitrogen and ammonia, allows obtaining films of three different ceramic materials: silicon dioxide, SiO2, silicon oxycarbide, SiOC and silicon oxynitride, SiON respectively. 相似文献
394.
Dr. Louise La Pensée Dr. Sunil Sabbani Dr. Raman Sharma Dr. Inder Bhamra Emma Shore Dr. Amy E. Chadwick Dr. Neil G. Berry James Firman Dr. Nuna C. Araujo Lília Cabral Prof. Maria L. S. Cristiano Cerys Bateman Dr. Omar Janneh Adelina Gavrila Yi Hang Wu Afthab Hussain Prof. Stephen A. Ward Dr. Paul A. Stocks Prof. Rick Cosstick Prof. Paul M. O'Neill 《ChemMedChem》2013,8(5):709-718
395.
Dr. Louise La Pensée Dr. Sunil Sabbani Dr. Raman Sharma Dr. Inder Bhamra Emma Shore Dr. Amy E. Chadwick Dr. Neil G. Berry James Firman Dr. Nuna C. Araujo Lília Cabral Prof. Maria L. S. Cristiano Cerys Bateman Dr. Omar Janneh Adelina Gavrila Yi Hang Wu Afthab Hussain Prof. Stephen A. Ward Dr. Paul A. Stocks Prof. Rick Cosstick Prof. Paul M. O'Neill 《ChemMedChem》2013,8(5):674-674
396.
Comparison of Response Surface Methodology and Artificial Neural Network for Modeling Xylose‐to‐Xylitol Bioconversion
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Fábio Coelho Sampaio Janaína Teles de Faria Gabriel Dumond de Lima Silva Ricardo Melo Gonçalves Cristiano Grijó Pitangui Alessandro Alberto Casazza Saleh Al Arni Attilio Converti 《化学工程与技术》2017,40(1):122-129
Previous experimental data of xylose‐to‐xylitol bioconversion by Debaryomyces hansenii carried out according to a 33 full factorial design were used to model this process by two different artificial neural network (ANN) training methods. Models obtained for four responses were compared with those of response surface methodology (RSM). ANN models were shown to be superior to RSM in the predictive capacity, whereas the latter showed better performance in the generalization capability step. RSM with optimization using a genetic algorithm was revealed as a whole to be the best modeling option, which suggests that the comparative performances of RSM and ANN may be a highly problem‐specific issue. 相似文献
397.
The structural volume changes following photoexcitation of o-nitrobenzyl systems are used to estimate the excited state pKa of the aci-nitro intermediate in aqueous solutions. The rather large contractions induced in solution by UV excitation are due to the rapid deprotonation of the short-lived aci-nitro intermediate, which leads to the formation of two charged species. The magnitude of the measured contraction as a function of the pH in acidic solutions follows a sigmoidal curve, from which it is possible to extract the pKa of the aci-nitro intermediate. This method is generally applicable to short-lived intermediates with stronger acid character than the parent compound, provided they undergo irreversible chemical transformations to a product that cannot rebind the photodetached proton. The reaction volume for water formation from its ionic constituents at basic pH allows the determination of the deprotonation quantum yields. 相似文献
398.
Generic Structures of Cytotoxic Liprotides: Nano‐Sized Complexes with Oleic Acid Cores and Shells of Disordered Proteins
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Dr. Jørn D. Kaspersen Jannik N. Pedersen Dr. Jon G. Hansted Dr. Søren B. Nielsen Srinivasan Sakthivel Dr. Kristina Wilhelm Dr. Ekaterina L. Nemashkalova Prof. Dr. Sergei E. Permyakov Prof. Dr. Eugene A. Permyakov Prof. Dr. Cristiano Luis Pinto Oliveira Prof. Dr. Ludmilla A. Morozova‐Roche Prof. Dr. Daniel E. Otzen Prof. Dr. Jan Skov Pedersen 《Chembiochem : a European journal of chemical biology》2014,15(18):2693-2702
The cytotoxic complex formed between α‐lactalbumin and oleic acid (OA) has inspired many studies on protein–fatty acid complexes, but structural insight remains sparse. After having used small‐angle X‐ray scattering (SAXS) to obtain structural information, we present a new, generic structural model of cytotoxic protein–oleic acid complexes, which we have termed liprotides (lipids and partially denatured proteins). Twelve liprotides formed from seven structurally unrelated proteins and prepared by different procedures all displayed core–shell structures, each with a micellar OA core and a shell consisting of flexible, partially unfolded protein, which stabilizes the OA micelle. The common structure explains similar effects exerted on cells by different liprotides and is consistent with a cargo off‐loading of the OA into cell membranes. 相似文献
399.
Julia Rabelo Vaz Matheus Raul Remor Dalsasso Evertan Antonio Rebelatto Kátia Suzana Andrade Lidiane Maria de Andrade Cristiano José de Andrade Alcilene Rodrigues Monteiro Ana Elizabeth Cavalcante Fai 《Comprehensive Reviews in Food Science and Food Safety》2023,22(2):1148-1183
The ideal food packaging materials are recyclable, biodegradable, and compostable. Starch from plant sources, such as tubers, legumes, cereals, and agro-industrial plant residues, is considered one of the most suitable biopolymers for producing biodegradable films due to its natural abundance and low cost. The chemical modification of starch makes it possible to produce films with better technological properties by changing the functional groups into starch. Using biopolymers extracted from agro-industrial waste can add value to a raw material that would otherwise be discarded. The recent COVID-19 pandemic has driven a rise in demand for single-use plastics, intensifying pressure on this already out-of-control issue. This review provides an overview of biopolymers, with a particular focus on starch, to develop sustainable materials for food packaging. This study summarizes the methods and provides a potential approach to starch modification for improving the mechanical and barrier properties of starch-based films. This review also updates some trends pointed out by the food packaging sector in the last years, considering the impacts of the COVID-19 pandemic. Perspectives to achieve more sustainable food packaging toward a more circular economy are drawn. 相似文献
400.
Renato Dias Matosinhos Karina Cesca Bruno Augusto Mattar Carciofi Débora de Oliveira Cristiano José de Andrade 《Journal of the science of food and agriculture》2023,103(1):37-47
Biosurfactants can be applied in the formulation of personal care products, as food additives, and as biocontrol agents in the agricultural sector. Glycolipids and lipopeptides represent an important group of microbial-based biosurfactants with biostimulating properties. Among them, the mannosylerythritol lipids also presented antimicrobial activity, mostly against Gram-positive bacteria and phytopathogenic fungi. In this sense, mannosylerythritol lipids are a potential safer green alternative for partially replacing synthetic pesticides. This review aimed to critically discuss the current state of the art and future trends of mannosylerythritol lipids as green pesticides and biostimulants for seed germination and plant growth. Due to their chemical structure, mannosylerythritol lipids are likely related to energy pathways such as glycolysis and Krebs cycle, i.e. a direct cellular biostimulant potential. In this case, experimental evidence from other glycolipids indicated that structural and chemical changes as a potential drug vehicle due to morphological changes caused by biosurfactant–membrane interaction. In addition, like other biosurfactants, mannosylerythritol lipids can trigger self-defense mechanisms, leading to a lower frequency of phytopathogen infections. Therefore, mannosylerythritol lipids have the potential for biostimulation and antiphytopathogenic action, despite that to date no data are available on mannosylerythritol lipids as biostimulants and green pesticides simultaneously. Based on the current state of the art, mannosylerythritol lipids have great potential for a biotechnological advance toward more sustainable agriculture. © 2022 Society of Chemical Industry. 相似文献