Factors Controlling The Deposition Of Silk Fibroin Nanofibrils During Layer-by-layer Assembly.

The layer-by-layer technique has been used as a powerful method to produce multilayer thin films with tunable properties. When natural polymers are employed, complicated phenomena such as self-aggregation and fibrilogenesis can occur, making it more difficult to obtain and characterize high-quality films. The weak acid and base character of such materials provides multilayer systems that may differ from those found with synthetic polymers due to strong self-organization effects. Specifically, LbL films prepared with chitosan and silk fibroin (SF) often involve the deposition of fibroin fibrils, which can influence the assembly process, surface properties, and overall film functionality. In this case, one has the intriguing possibility of realizing multilayer thin films with aligned nanofibers. In this article, we propose a strategy to control fibroin fibril formation by adjusting the assembly partner. Aligned fibroin fibrils were formed when chitosan was used as the counterpart, whereas no fibrils were observed when poly(allylamine hydrochloride) (PAH) was used. Charge density, which is higher in PAH, apparently stabilizes SF aggregates on the nanometer scale, thereby preventing their organization into fibrils. The drying step between the deposition of each layer was also crucial for film formation, as it stabilizes the SF molecules. Preliminary cell studies with optimized multilayers indicated that cell viability of NIH-3T3 fibroblasts remained between 90 and 100% after surface seeding, showing the potential application of the films in the biomedical field, as coatings and functional surfaces.

Estruturas factivas e padrões de extração

This paper investigates the relationship between structural and semantic properties of factive sentences and the pattern of extraction exhibited. It is argued that a classification as weak or strong island is unfeasible for what has been termed Factive Island. The kinds of structures allowed as factive complements are analyzed as well as their corresponding behavior concerning extraction. The common feature these structures show is their presuppositional character, which is derived from a selection requirement. I assume that factive predicates select a [+ specific] complement. The differences showed concerning extraction constitute a spontaneous effect from the structural way each construction may satisfy this requirement.

O ambiente virtual de aprendizagem e sua incorporação na Unicamp

The text describes a study about the adoption of virtual learning environments and its consequences to the learning process of undergraduate students at the State University of Campinas - Unicamp. These environments can be incorporated in various ways into the academic daily life of students and teachers. One efficient way to promote the adoption of these environments, as observed by the Distance Learning support team, is to train teachers and students in their use. Two training alternatives are described in this text to instruct the academic community in the use of TelEduc, a freeware developed and coordinated by the NIED - Núcleo de Informática Aplicada à Educação (Center for Information Technology Applied to Education), and officially adopted by Unicamp. Training courses are offered in two ways - presence or distance learning - to suit each teacher's preferences. This article compares the two modes of training, showing their strong and weak points. The adoption of TelEduc and its direct consequences to the learning process are described in a study carried out with some engineering undergraduates at Unicamp. The authors' questions and the general views of teachers and students regarding the effectiveness of the use of TelEduc as a supporting tool to presence teaching are presented. This investigation revealed the importance of training teachers in the effective use of these environments.

Desenvolvimento de equações generalizadas para estimativa da coordenação motora em crianças e adolescentes portadores de deficiencia mental

Universidade Estadual de Campinas . Faculdade de Educação Física

Adaptações geometricas da coluna vertebral durante a marcha

Universidade Estadual de Campinas . Faculdade de Educação Física

Aspectos motores da Paralisia Cerebral Espástica diparética : o Nintendo WII 'MARCA REGISTRADA' como atividade motora complementar = Motor aspects of Spastic Cerebral Palsy : the Nintendo WII 'TRADEMARK' as a supplementary motor activity

Universidade Estadual de Campinas . Faculdade de Educação Física

Mensuração da potência mecânica em esforços de alta intensidade na condição laboratorial de corrida atada e na condição de campo em corrida semi-atada e livre

Universidade Estadual de Campinas . Faculdade de Educação Física

Aplicação da escala de qualidade de vida em crianças de 07 a 12 anos praticantes de atividade fisica em academia e suas relações com a aptidão fisica

Universidade Estadual de Campinas . Faculdade de Educação Física

Avaliação motora para a pessoa deficiente mental nas APAEs da região de Campinas-SP : um estudo de caso

Universidade Estadual de Campinas. Faculdade de Educação Física

Teste de banco com carga continua para analise do volume de oxigenio (VO2) predito e analisado por tempo de esforço em pessoas treinadas (TRD), ativas (ATV) e destreinadas (DTR) a partir dos 13 anos : proposta de validação

Universidade Estadual de Campinas . Faculdade de Educação Física

Transformação das aulas de educação fisica : uma intervenção atraves dos jogos cooperativos

Universidade Estadual de Campinas . Faculdade de Educação Física

Atividade fisica e sintomas musculo-esqueleticos : explorando relações em população de calouros de medicina

Universidade Estadual de Campinas. Faculdade de Educação Física

Análise biomecânica da postura durante a ortostase e a locomoção

Universidade Estadual de Campinas . Faculdade de Educação Física

Fluoride release profile of a nanofilled resin-modified glass ionomer cement

The present study aimed to compare the fluoride (F-) release pattern of a nanofilled resin-modified glass ionomer cement (GIC) (Ketac N100 - KN) with available GICs used in dental practice (resin-modified GIC - Vitremer - V; conventional GIC - Ketac Molar - KM) and a nanofilled resin composite (Filtek Supreme - RC). Discs of each material (n=6) were placed into 4 mL of deionized water in sealed polyethylene vials and shaken, for 15 days. F- release (μg F-/cm²) was measured each day using a fluoride-ion specific electrode. Cumulative F- release means were statistically analyzed by linear regression analysis. In order to analyze the differences among materials and the influence of time in the daily F- release, 2-way ANOVA test was performed (α=0.05). The linear fits between the cumulative F- release profiles of RC and KM and time were weak. KN and V presented a strong relationship between cumulative F- release and time. There were significant differences between the daily F- release overtime up to the third day only for GICs materials. The daily F- release means for RC were similar overtime. The results indicate that the F- release profile of the nanofilled resin-modified GIC is comparable to the resin-modified GIC.

Influence of incorporation of fluoroalkyl methacrylates on roughness and flexural strength of a denture base acrylic resin

Fluorinated denture base acrylic resins can present more stable physical properties when compared with conventional polymers. This study evaluated the incorporation of a fluoroalkyl methacrylate (FMA) mixture in a denture base material and its effect on roughness and flexural strength. A swelling behavior assessment of acrylic resin specimens (n=3, per substance) after 12 h of FMA or methyl methacrylate (MMA) immersion was conducted to determine the solvent properties. Rectangular specimens (n=30) were allocated to three groups, according to the concentration of FMA substituted into the monomer component of a heat-polymerized acrylic resin (Lucitone 550), as follows: 0% (control), 10% and 20% (v/v). Acrylic resin mixed with concentrations of 25% or more did not reach the dough stage and was not viable. The surface roughness and flexural strength of the specimens were tested. Variables were analyzed by ANOVA and Tukey's test (a=0.05). Immersion in FMA produced negligible swelling, and MMA produced obvious swelling and dissolution of the specimens. Surface roughness at concentrations of 0%, 10% and 20% were: 0.25 ± 0.04, 0.24 ± 0.04, 0.22 ± 0.03 mm (F=1.78; p=0.189, not significant). Significant differences were found for flexural strength (F=15.92; p<0.001) and modulus of elasticity (F=7.67; p=0.002), with the following results: 96 ± 6, 82 ± 5, 84 ± 6 MPa, and 2,717 ± 79, 2,558 ± 128, 2574 ± 87 MPa, respectively. The solvent properties of FMA against acrylic resin are weak, which would explain why concentrations over 20% were not viable. Surface changes were not detected after the incorporation of FMA in the denture base acrylic resin tested. The addition of FMA into denture base resin may lower the flexural strength and modulus of elasticity, regardless of the tested concentration.