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511.
512.
Gianluca Giavaresi Milena Fini Jonathan Salvage Nicolò Nicoli Aldini Roberto Giardino Luigi Ambrosio Luigi Nicolais Matteo Santin 《Journal of materials science. Materials in medicine》2010,21(2):615-626
Autologous and allogenic bone grafts are considered as materials of choice for bone reconstructive surgery, but limited availability, risks of transmittable diseases and inconsistent clinical performances have prompted the development of alternative biomaterials. The present work compares the bone regeneration potential of a soybean based bone filler (SB bone filler) in comparison to a commercial 50:50 poly(d,l lactide–glycolide)-based bone graft (Fisiograft® gel) when implanted into a critical size defect (6-mm diameter, 10-mm length) in rabbit distal femurs. The histomorphometric and microhardness analyses of femoral condyles 4, 8, 16 and 24 weeks after surgery showed that no significant difference was found in the percentage of both bone repair and bone in-growth in the external, medium and inner defect areas. The SB filler-treated defects showed significantly higher outer bone formation and microhardness results at 24 weeks than Fisiograft® gel (P < 0.05). Soybean-based biomaterials clearly promoted bone repair through a mechanism of action that is likely to involve both the scaffolding role of the biomaterial for osteoblasts and the induction of their differentiation. 相似文献
513.
Silvia Luciana Fávaro Milena Savioli Lopes Alberto Gonçalves Vieira de Carvalho Neto Ricardo Rogério de Santana Eduardo Radovanovic 《Composites Part A》2010,41(1):154-160
Composites were obtained from post-consumer high-density polyethylene (PE) reinforced with different concentrations of rice husk. PE and rice husk were chemically modified to improve their compatibility in composite preparation. Rice husk was mercerized with a NaOH solution and acetylated. The chemically modified fibers were characterized by FTIR and 13C NMR spectroscopy. The composites were prepared by extrusion of modified and unmodified materials containing either 5 or 10 wt.% fibers. The morphology of the obtained materials was analyzed by SEM. The chemical modification of the fiber surface was found to improve its adhesion with matrix. Flexural and impact tests demonstrated that PE/rice husk composites present improved mechanical performance comparatively to the pure polymer matrix, on the contrary no benefit is observed in the tensile strength over the pure PE. 相似文献
514.
Leonardo Petruzzi Daniela Campaniello Barbara Speranza Maria Rosaria Corbo Milena Sinigaglia Antonio Bevilacqua 《Comprehensive Reviews in Food Science and Food Safety》2017,16(4):668-691
Fruit and vegetable juices and beverages are generally preserved by thermal processing, currently being the most cost‐effective means ensuring microbial safety and enzyme deactivation. However, thermal treatments may induce several chemical and physical changes that impair the organoleptic properties and may reduce the content or bioavailability of some nutrients; in most cases, these effects are strongly dependent on the food matrix. Moreover, the efficacy of treatments can also be affected by the complexity of the product and microorganisms. This review covers researches on this topic, with a particular emphasis on products derived from different botanical sources. Technologies presented include conventional and alternative thermal treatments. Advances toward hurdle‐based technology approaches have been also reviewed. 相似文献
515.
Identification and Synthesis of a Kairomone Mediating Host Location by Two Parasitoid Species of the Cassava Mealybug Phenacoccus herreni 总被引:2,自引:0,他引:2
Calatayud PA Auger J Thibout E Rousset S Caicedo AM Calatayud S Buschmann H Guillaud J Mandon N Bellotti AC 《Journal of chemical ecology》2001,27(11):2203-2217
Two encyrtid species, Acerophagus coccois and Aenasius vexans, parasitoids of the cassava mealybug Phenacoccus herreni use a contact kairomone from the body surface of their host as a host-location stimulant. The kairomone was synthesized and identified as O-caffeoylserine based on a combination of chromatographic methods. The synthetic compound was determined to be active. 相似文献
516.
Design aesthetics leading to m-loyalty in mobile commerce 总被引:4,自引:0,他引:4
Researchers have previously examined the technology acceptance model (TAM) in many contexts, including the Internet. More recently TAM has been enhanced to include a hedonic component of enjoyment but the effect has rarely been investigated in a mobile commerce context. In addition, specific antecedents of TAM related to design aesthetics have not been examined within the mobile domain. Our research filled these gaps, and discovered that visual design aesthetics did significantly impact perceived usefulness, ease of use, and enjoyment, all of which ultimately influenced users’ loyalty intentions towards a mobile service. 相似文献
517.
Justyna Sawicka Emilia Iowska Milena Deptua Pawe Sosnowski Piotr Sass Katarzyna Czerwiec Klaudia Chmielewska Aneta Szymaska Zuzanna Pietralik-Moliska Maciej Kozak Pawe Sachadyn Micha Pikua Sylwia Rodziewicz-Motowido 《International journal of molecular sciences》2021,22(8)
Technological developments in the field of biologically active peptide applications in medicine have increased the need for new methods for peptide delivery. The disadvantage of peptides as drugs is their low biological stability. Recently, great attention has been paid to self-assembling peptides that can form fibrils. Such a formulation makes bioactive peptides more resistant to enzymatic degradation and druggable. Peptide fibrils can be carriers for peptides with interesting biological activities. These features open up prospects for using the peptide fibrils as long-acting drugs and are a valid alternative to conventional peptidic therapies. In our study, we designed new peptide scaffolds that are a hybrid of three interconnected amino acid sequences and are: pro-regenerative, cleavable by neutrophilic elastase, and fibril-forming. We intended to obtain peptides that are stable in the wound environment and that, when applied, would release a biologically active sequence. Our studies showed that the designed hybrid peptides show a high tendency toward regular fibril formation and are able to release the pro-regenerative sequence. Cytotoxicity studies showed that all the designed peptides were safe, did not cause cytotoxic effects and revealed a pro-regenerative potential in human fibroblast and keratinocyte cell lines. In vivo experiments in a dorsal skin injury model in mice indicated that two tested peptides moderately promote tissue repair in their free form. Our research proves that peptide fibrils can be a druggable form and a scaffold for active peptides. 相似文献
518.
Milena P. Arciniegas Andrea Castelli Rosaria Brescia David Serantes Sergiu Ruta Ondrej Hovorka Akira Satoh Roy Chantrell Teresa Pellegrino 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(25)
The controlled assembly of colloidal magnetic nanocrystals is key to many applications such as nanoelectronics, storage memory devices, and nanomedicine. Here, the motion and ordering of ferrimagnetic nanocubes in water via liquid‐cell transmission electron microscopy is directly imaged in situ. Through the experimental analysis, combined with molecular dynamics simulations and theoretical considerations, it is shown that the presence of highly competitive interactions leads to the formation of stable monomers and dimers, acting as nuclei, followed by a dynamic growth of zig‐zag chain‐like assemblies. It is demonstrated that such arrays can be explained by first, a maximization of short‐range electrostatic interactions, which at a later stage become surpassed by magnetic forces acting through the easy magnetic axes of the nanocubes, causing their tilted orientation within the arrays. Moreover, in the confined volume of liquid in the experiments, interactions of the nanocube surfaces with the cell membranes, when irradiated at relatively low electron dose, slow down the kinetics of their self‐assembly, facilitating the identification of different stages in the process. The study provides crucial insights for the formation of unconventional linear arrays made of ferrimagnetic nanocubes that are essential for their further exploitation in, for example, magnetic hyperthermia, magneto‐transport devices, and nanotheranostic tools. 相似文献
519.
Nikša Tadić Wolfgang Gaberl Milena Zogović Horst Zimmermann 《Analog Integrated Circuits and Signal Processing》2011,66(2):293-298
A 0.35 μm SiGe BiCMOS optical receiver with voltage-controlled transimpedance is presented. A variable-gain current amplifier
using a BJT translinear loop is applied. A transimpedance dynamic range of 1554 (63.8 dB) with the largest transimpedance
of 2.84 MΩ, a bandwidth up to 379 MHz, and a transimpedance bandwidth product up to 168 TΩHz are achieved. 相似文献
520.
Josep Rubert Milena Zachariasova Jana Hajslova 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2015,32(10):1685-1708
Food authenticity becomes a necessity for global food policies, since food placed in the market without fail has to be authentic. It has always been a challenge, since in the past minor components, called also markers, have been mainly monitored by chromatographic methods in order to authenticate the food. Nevertheless, nowadays, advanced analytical methods have allowed food fingerprints to be achieved. At the same time they have been also combined with chemometrics, which uses statistical methods in order to verify food and to provide maximum information by analysing chemical data. These sophisticated methods based on different separation techniques or stand alone have been recently coupled to high-resolution mass spectrometry (HRMS) in order to verify the authenticity of food. The new generation of HRMS detectors have experienced significant advances in resolving power, sensitivity, robustness, extended dynamic range, easier mass calibration and tandem mass capabilities, making HRMS more attractive and useful to the food metabolomics community, therefore becoming a reliable tool for food authenticity. The purpose of this review is to summarise and describe the most recent metabolomics approaches in the area of food metabolomics, and to discuss the strengths and drawbacks of the HRMS analytical platforms combined with chemometrics. 相似文献