Search results for "C120"
showing 10 items of 297 documents
Hedysarum coronarium-Based Green Composites Prepared by Compression Molding and Fused Deposition Modeling
2022
In this work, an innovative green composite was produced by adding Hedysarum coronarium (HC) flour to a starch-based biodegradable polymer (Mater-Bi®, MB). The flour was obtained by grinding together stems, leaves and flowers and subsequently sieving it, selecting a fraction from 75 μm to 300 μm. Four formulations have been produced by compression molding (CM) and fused deposition modeling (FDM) by adding 5%, 10%, 15% and 20% of HC to MB. The influence of filler content on the processability was tested, and rheological, morphological and mechanical properties of composites were also assessed. Through CM, it was possible to obtain easily homogeneous samples with all filler amounts.…
Creep Behavior of Poly(lactic acid) Based Biocomposites
2017
Polymer composites containing natural fibers are receiving growing attention as possible alternatives for composites containing synthetic fibers. The use of biodegradable matrices obtained from renewable sources in replacement for synthetic ones is also increasing. However, only limited information is available about the creep behavior of the obtained composites. In this work, the tensile creep behavior of PLA based composites, containing flax and jute twill weave woven fabrics, produced through compression molding, was investigated. Tensile creep tests were performed at different temperatures (i.e., 40 and 60 °C). The results showed that the creep behavior of the composites is strongly inf…
Reinforcement Efficiency of Cellulose Microfibers for the Tensile Stiffness and Strength of Rigid Low-Density Polyurethane Foams
2020
Rigid low-density closed-cell polyurethane (PU) foams are widely used in both thermal insulation and structural applications. The sustainability of PU foam production can be increased by using bio-based components and fillers that ensure both enhanced mechanical properties and higher renewable material content. Such bio-based foams were produced using polyols derived from rapeseed oil and microcrystalline cellulose (MCC) fibers as filler. The effect of MCC fiber loading of up to 10 wt % on the morphology, tensile stiffness, and strength of foams has been evaluated. For estimation of the mechanical reinforcement efficiency of foams, a model allowing for the partial alignment of filler fibers…
Effects of exercise on life quality in a rheumatoid arthritis patient
2020
Rheumatoid arthritis (RA) is a chronic-degenerative disease characterized by symptoms that significantly impact on the functional capacity and thus, the ability to carry out daily functional activities reducing the quality of life (QoL). The aim was to evaluate the effects of a strength and conditioning (S&C) program on the quality of life (QoL), the self-perception disease impact, the self-fatigue perception and cardiovascular risk factors in a patient with rheumatoid arthritis (RA) and cardiovascular disease (CVD). 34-year-old woman (height: 1.40m; weight: 36.1kg) diagnosed with RA and CVD underwent a six-month S&C program with aerobic training 2-3 times a week in 1-3 sets of 5-15 minutes…
Longitudinal associations of physical activity and pubertal development with academic achievement in adolescents.
2020
Highlights • Boys with higher levels of moderate-to-vigorous physical activity had better academic achievement than those with lower levels of physical activity at baseline. • Physical activity was not associated with academic achievement at follow-up in boys or girls. • Continuously inactive adolescents had poorer academic achievement over the follow-up period than their more active peers. • Girls with more advanced pubertal status had better academic achievement than other girls.
A single bout of physical exercise does not affect young adults’ executive functions
2020
Summary Study aim. The purpose of the current study is to determine the impact of single bouts of physical exercise of different duration and intensity on young adults’ executive functions. Material and methods. The study employed 81 participants (37 females, 44 males) ranging between 19 and 39 years (mean age: 24.6 ± 4.08 years; mean height: 168 ± 9.67 cm; mean weight: 67.2 ± 13.0 kg). The executive functions were assessed through the Stroop task, the Tower of London test, and the Corsi block test. Participants were randomly assigned to one of the three experimental conditions (30-second Wingate test condition, an incremental intensity exercise test, and a submaximal constant-intensity tes…
Organizational Culture Beyond Consensus and Clarity: Narratives From Elite Sport
2020
In sport psychology, organizational culture is usually depicted as shared, consistent, and clear—the glue that holds people together so they can achieve success. There is, however, growing discontent in sport psychology with this idea of culture and extensive critiques in other academic domains that suggest this perspective is limited. Accordingly, the authors draw on narrative interviews with participants (n = 7) from different areas of sport and use Martin and Meyerson’s three perspective (integration, differentiation, and fragmentation) approach to culture alongside thematic analysis to reconstruct three “ideal cases” that exemplify each perspective. The findings emphasize a different pa…
Comparative Surface Morphology, Chemical Composition, and Cytocompatibility of Bio-C Repair, Biodentine, and ProRoot MTA on hDPCs
2020
Biocompatibility is an essential property for any vital pulp material that may interact with the dental pulp tissues. Accordingly, this study aimed to compare the chemical composition and ultrastructural morphology of Biodentine (Septodont, Saint Maur-des-Fosses, France), ProRoot MTA (Dentsply Tulsa Dental Specialties, Johnson City, TN, USA), and Bio-C Repair (Angelus, Londrina, PR, Brazil), as well as their biological effects on human dental pulp cells. Chemical element characterization of the materials was undertaken using scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDX). The cytotoxicity was assessed by analyzing the cell viability (MTT assay), cell morphology …
Respostas mecânicas da musculatura do joelho de bodyboarders de alto nível durante o desempenho
2015
INTRODUCTION: bodyboarding is a kind of surfing that has been growing very rapidly over the last decade and has now developed into one of the fastest growing water sports in the world.OBJECTIVES: evaluate the effects of fatigue on rectus femoris RF, vastus lateralis VL and vastus medialis VM and biceps femoris BF and semitendinosus ST during a high-level bodyboard competition using tensiomyography TMG.METHODS: subjects were 11 highly experienced years of practice: 15, SD=4.65 male bodyboarders age: 28.17, SD=2.89, body weight: 74.83, SD=6.13kg; height: 179.25, SD=3.93cm; BMI: 23.29, SD=1.81 participating in the final of the 2010 Spanish championship.RESULTS: the fatigue is especially eviden…
The Impact of the Progressive Efficiency Test on a Rowing Ergometer on White Blood Cells Distribution and Clinical Chemistry Changes in Paralympic Ro…
2017
Abstract There is a large gap in knowledge regarding research on post-exercise blood changes in disabled athletes. There are relatively few data on adaptive mechanisms to exercise in disabled athletes, including disabled rowers. Two rowers from a Polish adaptive rowing settle TAMix2x that qualified for the Paralympic Games in Rio, 2016 took part in this study. They performed a progressive test on a rowing ergometer until exhaustion. The cardiorespiratory fitness measures, complete blood count, white blood cells’ distribution and 30 clinical chemistry variables describing laboratory diagnostic profiles and general health were determined. The extreme effort induced changes in all studied meta…