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41.
Konstantinos D. Antoniadis Marc J. Assael Christine A. Tsiglifisi Sofia K. Mylona 《International Journal of Thermophysics》2012,33(12):2274-2290
The hollow clay brick is the typical building unit that is employed not only over the whole Greece but also in many other Mediterranean countries. Nevertheless, its design is completely empirical. In this study, the design of the hollow clay brick is analyzed by employing a finite element package. To carry out this analysis, the thermal conductivity of the solid clay is measured by the transient hot-wire technique. As a consequence of the analysis, an improvement of 24 % in the design of the hollow clay brick is proposed. 相似文献
42.
S. I. Correia H. Pereira J. Silva-Correia C. N. Van Dijk J. Espregueira-Mendes J. M. Oliveira R. L. Reis 《Journal of the Royal Society Interface》2014,11(92)
Tissue engineering and regenerative medicine (TERM) has caused a revolution in present and future trends of medicine and surgery. In different tissues, advanced TERM approaches bring new therapeutic possibilities in general population as well as in young patients and high-level athletes, improving restoration of biological functions and rehabilitation. The mainstream components required to obtain a functional regeneration of tissues may include biodegradable scaffolds, drugs or growth factors and different cell types (either autologous or heterologous) that can be cultured in bioreactor systems (in vitro) prior to implantation into the patient. Particularly in the ankle, which is subject to many different injuries (e.g. acute, chronic, traumatic and degenerative), there is still no definitive and feasible answer to ‘conventional’ methods. This review aims to provide current concepts of TERM applications to ankle injuries under preclinical and/or clinical research applied to skin, tendon, bone and cartilage problems. A particular attention has been given to biomaterial design and scaffold processing with potential use in osteochondral ankle lesions. 相似文献
43.
M. Muñoz A. Uyar E. Correia C. Díez A. Fernandez-Gonzalez J.N. Caamaño D. Martínez-Bello B. Trigal P. Humblot C. Ponsart C. Guyader-Joly S. Carrocera D. Martin B. Marquant Le Guienne E. Seli E. Gomez 《Journal of dairy science》2014
We analyzed embryo culture medium (CM) and recipient blood plasma using Fourier transform infrared (FTIR) metabolomics to predict pregnancy outcome. Individually cultured, in vitro-produced (IVP) blastocysts were transferred to recipients as fresh and vitrified-warmed. Spent CM and plasma samples were evaluated using FTIR. The discrimination capability of the classifiers was assessed for accuracy, sensitivity (pregnancy), specificity (nonpregnancy), and area under the receiver operator characteristic curve (AUC). Within all IVP fresh embryos (birth rate = 52%), high AUC were obtained at birth, especially with expanded blastocysts (CM: 0.80 ± 0.053; plasma: 0.89 ± 0.034). The AUC of vitrified IVP embryos (birth rate = 31%) were 0.607 ± 0.038 (CM, expanded blastocysts) and 0.672 ± 0.023 (plasma, all stages). Recipient plasma generally predicted pregnancy outcome better than did embryo CM. Embryos and recipients with improved pregnancy viability were identified, which could increase the economic benefit to the breeding industry. 相似文献
44.
The objective of this study was to evaluate the shelf life of powdered guavira pulp obtained by a foam mat drying process. The dehydrated guavira pulp was packed into low density polyethylene (LDPE) bags and stored under two controlled conditions: environmental (25 °C, RH 75%) and accelerated (35 °C, RH 90%) for 90 days. The shelf life was accompanied by carrying out the following analyses every 10 days: moisture content, water activity, vitamin C content, pH and titratable acidity. Vitamin C was the quality attribute used to determine the shelf life of the product, by determining its degradation kinetics as a function of storage time. The linear regression data showed that the vitamin C degradation reaction fitted the zero and first order kinetic models. The shelf life of the powdered guavira pulp under environmental conditions was approximately 49 days, and under accelerated conditions (35 °C) 45 days. The Q10 was equal to 1.09, predicting a shelf life similar to that found under environmental conditions. The moisture content for these conditions was 10.0% e 5.4% for 35 °C and 25 °C, respectively. The above demonstrate the efficiency of the accelerated test in predicting the shelf life of the product. 相似文献
45.
Multimedia Tools and Applications - A personal collection of photos shows large variability in the depicted items, making difficult a fully automated solution to cope with sensory and semantic... 相似文献
46.
B. P. Falcão J. P. Leitão J. C. González M. R. Correia K. G. Zayas-Bazán F. M. Matinaga M. B. Moreira C. F. Leite A. G. de Oliveira 《Journal of Materials Science》2013,48(4):1794-1798
Mg-doped GaAs nanowires have been grown by molecular beam epitaxy on a partially Au-coated Si(111) substrate by the vapor–liquid–solid mechanism. Outside the coated areas, a thin film of GaAs was grown epitaxially at the same time. The optical properties in both parts of the sample were investigated by photoluminescence spectroscopy, as a function of temperature. A structured emission in the range ~1.25–1.55 eV was observed at 10 K and the resemblances in both cases were identified. The radiative transitions are discussed with relevance to known defect centers in the GaAs thin films and to their possible relation with the zinc-blende and wurtzite phases in the nanowires. The presence of both crystalline phases in the nanowires was confirmed by μ-Raman spectroscopy. 相似文献
47.
Ioannis K. Karabagias Evangelia Z. Halatsi Stavros Kontakos Sofia Karabournioti Michael G. Kontominas 《International Journal of Food Properties》2017,20(11):2699-2710
The aim of the present study was to investigate the volatile fraction and discriminate 34 commercial thyme honeys from Morocco, Egypt, Spain, and Greece according to geographical origin, using key volatile compounds in combination with chemometrics. Sixty-two volatile compounds belonging to different classes were identified and semi-quantified using headspace solid phase micro-extraction coupled to gas chromatography/mass spectrometry (HS-SPME-GC/MS). Applying chemometric analyses to 17 volatiles (p < 0.05), honeys were successfully discriminated according to geographical origin. Correct classification rate was 88.2% using the cross-validation method. Volatile compounds proved to be a powerful tool for discriminating commercial thyme honeys from different countries. 相似文献
48.
Sofia Teixeira de Freitas Henk Kolstein Frans Bijlaard 《Computer-Aided Civil and Infrastructure Engineering》2012,27(2):143-153
Abstract: The article presents renovation solutions for orthotropic steel bridge decks consisting of bonding a second steel plate to the existing steel deck in order to reduce the stresses and enlarge the life span of the orthotropic bridge deck. Two solutions for the interface layer between the existing deck plate and the second steel plate are presented: thin epoxy (bonded system) and thick polyurethane (sandwich system). A parametric study based on analytical solutions is carried out on flexural behavior of beams representing the renovation solutions. The influence of geometrical, mechanical and structural parameters on the stiffness and stress reduction factor of the system is studied. Maximum values of stiffness and stress reduction are achieved when maximizing the interface layer thickness and minimizing the second steel plate thickness with in certain practical limits. Based on the weight restrictions one can choose the most efficient interface layer regarding thickness and mechanical properties. 相似文献
49.
Anastasia Ktenioudaki Valérie Chaurin Sofia F. Reis Eimear Gallagher 《International Journal of Food Science & Technology》2012,47(8):1765-1771
Brewer’s spent grain (BSG) was evaluated for its potential as a functional baking ingredient. Scanning electron microscopy (SEM) was used to examine the microstructure of BSG and wheat flours. Baked snacks (breadsticks) were prepared using 15%, 25% and 35% BSG and evaluated for their baking quality and fibre and protein content (over a period of 3 months). The addition of BSG altered the baking characteristics of the breadsticks by affecting their structure and texture. The snacks appeared to lack in cellular structure and crispiness. However, they had quite a stable shelf‐life, as changes in texture, moisture and aw progressed at a low rate. Addition of 25% and 35% BSG significantly increased the protein content of the snacks, and addition of 15% BSG more than doubled the content of dietary fibre in the samples. 相似文献
50.
Total Diet Studies to estimate dietary exposure to food contaminants need to evaluate laboratory measurements data variance. In this process it is critical that data from analytical methods are reliable to correctly scrutinize and compare values over time and between countries. In Europe it is widely recognized that the evaluation of measurement uncertainty is an important parameter when assessing the sources of analytical data variability. Two approaches are considered to estimate uncertainty in analytical measurement. Arsenic, Lead, Chromium and Cadmium, content in several food matrix determined by Inductively Coupled Mass Spectrometry (ICP-MS) microwave digestion assisted, are used as examples. The aim of the present research work is to compare both approaches accepted by Eurolab and GUM: Mathematical modeling to assess uncertainty components based on a classical model (bottom up) and an empirical method (top down), based on either experimental data obtained from a single laboratory validation data or inter-laboratory data from Proficiency Testing schemes. Relative expanded uncertainty calculated by both approaches agree when U (%) <20%. These values are concordant with RSDR reported in collaborative studies of EN 15763 (2009), which were assumed as target uncertainty. The top down approach described is simple and easy to use when compared with the mathematical modeling approach providing considerable benefits to those who assess data produced by several laboratories. 相似文献