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131.
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133.
Eakin Elizabeth G.; Bull Sheana S.; Riley Kimberley M.; Reeves Marina M.; McLaughlin Patty; Gutierrez Silvia 《Canadian Metallurgical Quarterly》2007,26(4):392
Objective: The Resources for Health trial evaluates a social-ecologically based lifestyle (physical activity and diet) intervention targeting low-income, largely Spanish-speaking patients with multiple chronic conditions. Design: A randomized controlled trial was conducted with 200 patients recruited from an urban community health center and assigned to intervention and usual care conditions. Intervention involved 2 face-to-face, self-management support and community linkage sessions with a health educator, 3 follow-up phone calls, and 3 tailored newsletters. Main Outcome Measures: Primary outcomes measured at 6-months were changes in dietary behavior and physical activity. Changes in multilevel support for healthy living were evaluated as a secondary outcome. Results: After adjustment for age, sex, language, and number of chronic conditions, significant intervention effects were observed for dietary behavior and multilevel support for healthy lifestyles but not for physical activity. Conclusion: The Resources for Health intervention provides an effective and practical model for improving health behavior among low-income, Spanish-speaking patients with multiple chronic conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
Pankaj Agrawal Silvia I. Oliveira E. M. Araújo Tomas J. A. Melo 《Journal of Materials Science》2007,42(13):5007-5012
In this work, the rheological, mechanical and morphological properties of nylon 6/polypropylene compatibilized blends were
investigated. Two types of polypropylene were used. One with MFI of 40 g/10 min (PP H103) and the other with MFI of 3.5 g/10 min
(PP H503). The compatibilizers used were polypropylene grafted with 6% of acrylic acid (PPgAA) and polypropylene grafted with
1% of maleic anhydride (PPgMA). The blends composition was 80/20 (wt%) for the PA6/PP binary blends and 80/10/10(wt%) for
the nylon 6/PPgAA/polypropylene and nylon 6/PPgMA/polypropylene ternary blends. Torque rheometry analysis showed that when
PPgAA and PPgMA were added to nylon 6/polypropylene blends, there was an increase in the torque, indicating that reactive
compatibilization has occurred. There is no influence of the polypropylene MFI on the mechanical properties of the uncompatibilized
and compatibilized blends. The impact strength of the blends containing PPgMA were greater than those of the blends containing
PPgAA. The blends containing PPgAA are unstable. SEM analysis showed that PPgMA improves considerably the adhesion between
PA6/PP phases, leading to good mechanical properties. 相似文献
135.
Silvia Angelone Marina Cauhapé Casaux Manuel Borghi Fernando O. Martinez 《Materials and Structures》2016,49(5):1655-1665
Nowadays, the disposal of plastic waste is an issue of major concern worldwide because of its considerable volume and growth. An option to tackle this problem is to recycle this waste. This alternative reduces the quantity of net discards, conserves both material and energy and provides a comparatively simple way to make a substantial reduction in the overall volume of solid waste. The purpose of this study is to investigate an environmentally friendly approach about the influence of recycling different percentages of urban and rural plastic waste by adding them in a dry process on an asphalt mixture, through a comparative laboratory study. The resulting mixtures are analyzed considering their volumetric parameters and the values from diverse laboratory mechanical tests. The performance tests include, Marshall stability, Marshall quotient, indirect tensile strength, fracture energy, resilient modulus, permanent deformation and creep compliance, which were carried out on unmodified and modified hot asphalt mixtures. The obtained results are presented and discussed in this paper showing that the reuse of recycled plastics in asphalt mixtures is a viable alternative that contributes to the reduction of plastic wastes as well as the protection of the environment. 相似文献
136.
Silvia Minardi Bruna Corradetti Francesca Taraballi Monica Sandri Jonathan O. Martinez Sebastian T. Powell Anna Tampieri Bradley K. Weiner Ennio Tasciotti 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(11):1479-1488
Scaffolds functionalized with delivery systems for the release of growth factors is a robust strategy to enhance tissue regeneration. However, after implantation, macrophages infiltrate the scaffold, eventually initiating the degradation and clearance of the delivery systems. Herein, it is hypothesized that fully embedding the poly(d,l ‐lactide‐co‐glycolide acid) microspheres (MS) in a highly structured collagen‐based scaffold (concealing) can prevent their detection, preserving the integrity of the payload. Confocal laser microscopy reveals that non‐embedded MS are easily internalized; when concealed, J774 and bone marrow‐derived macrophages (BMDM) cannot detect them. This is further demonstrated by flow cytometry, as a tenfold decrease is found in the number of MS engulfed by the cells, suggesting that collagen can cloak the MS. This correlates with the amount of nitric oxide and tumor necrosis factor‐α produced by J774 and BMDM in response to the concealed MS, comparable to that found for non‐functionalized collagen scaffolds. Finally, the release kinetics of a reporter protein is preserved in the presence of macrophages, only when MS are concealed. The data provide detailed strategies for fabricating three dimensional (3D) biomimetic scaffolds able to conceal delivery systems and preserve the therapeutic molecules for release. 相似文献
137.
Tissue Engineering: Biomimetic Concealing of PLGA Microspheres in a 3D Scaffold to Prevent Macrophage Uptake (Small 11/2016) 下载免费PDF全文
138.
Rochelle Schneider dos Santos Silvia Beatriz Alves Rolim Fernando Hepp Pulgati 《International journal of remote sensing》2013,34(3):917-938
In the twenty-first century, there has been rapid urbanization in economically emerging countries. Many scientific research studies have proposed methods to monitor the quality of materials used in engineering works. Quality inspections are most often made of structure-related materials such as concrete. All the concrete used in construction work is subjected to a test that breaks the samples to evaluate its final mechanical strength. In this sense, remote sensing can contribute to mapping and monitoring construction materials, allowing investigation and identification of various properties such as mechanical strength and water content in a non-destructive manner. The materials can be inspected directly on site, in a rapid, non-invasive, and inexpensive manner; this is crucial for the ongoing process of construction. The spectral behaviour of four different mechanical strengths of two cement materials based on Portland cement, cement paste, and mortar was observed using a FieldSpec® 3 spectroradiometer. The spectral curves generated by recording the reflected and absorbed electromagnetic radiation of the samples were interpreted based on the theory of vibrational and electronic spectroscopy. The objective of this work is to show a novel technique for assisting in the analysis of solid samples using visible and near infrared spectroscopy. Through this study, a spectral contrast between different samples of the paste and mortar was found. Besides, it was possible to detect the presence and the corresponding proportion of water in the samples. Wavelet analysis enabled records of statistical evidence of spectral contrast, and showed that the depth of water absorption features is inversely proportional to compressive strength in the cement materials under study. This work is innovative, because there are no studies in the literature on the application of this technique as an aid tool for differentiating compressive strengths of Portland-cement-based materials. 相似文献
139.
Study of the effect of vintage,maturity degree,and irrigation on the amino acid and biogenic amine content of a white wine from the Verdejo variety 下载免费PDF全文
140.
Terenzio Bertuzzi Silvia Rastelli Annalisa Mulazzi Gianluca Donadini Amedeo Pietri 《Food Control》2011,22(12):2059-2064
The occurrence of ochratoxin A, trichothecenes, fumonisins and aflatoxins in a sample of 106 beers produced in several European countries, was investigated. The analyses were conducted using high-performance liquid chromatography with fluorimetric detection for ochratoxin A and aflatoxins, gas-chromatography and high-performance liquid chromatography, both coupled with mass spectrometer, for trichothecenes and fumonisins, respectively. Aflatoxins were not detected in any samples, whereas ochratoxin A, deoxynivalenol and fumonisins were found in a relatively high number of samples. Their presence was at low levels in all samples; however, some differences were observed between the European countries. As regards ochratoxin A, beer samples from southern Europe showed levels always lower than 0.040 μg l?1, while the samples from other European countries showed significantly higher values, up to 0.189 μg l?1 (P < 0.001). For fumonisins, the levels of Italian beers were significantly higher compared to the samples from other countries (P = 0.006). 相似文献