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111.
Marios C. Angelides Lissette Andrea Cabello Wilson Paola Liliana Burneo Echeverría 《Multimedia Tools and Applications》2018,77(20):26397-26448
Wearable technology comes with the promise of improving one’s lifestyles thru data mining of their physiological condition. The potential to generate a change in daily or routine habits thru these devices leaves little doubt. Whilst the hardware capabilities of wearables have evolved rapidly, software apps that interpret and present the physiological data and make recommendations in a simple, clear and meaningful way have not followed a similar pattern of evolution. Existing fitness apps provide routinely some information to the wearer by mining personal data but the subsequent analysis is limited to supporting ad hoc personal goals. The information and recommendations presented are often either not entirely relevant or incomplete and often not easy to interpret by the wearer. The primary motivation behind this research is to address this wearable technology software challenge by developing a middleware mobile app that is supported by data analytics and machine learning to assist with interpretation of wearer data and with making of personal lifestyle improvement recommendations on the go which may then be used to feedback to the wearer’s daily goals and activities. The secondary motivation is to correlate and compare with trends in the wearer’s peer community. 相似文献
112.
Lilian de Siqueira Rubia F. Gouveia Liliana Grenho Fernando J. Monteiro Maria H. Fernandes Eliandra S. Trichês 《Journal of Materials Science》2018,53(15):10718-10731
Several types of alloplastic (artificial) grafts, known as scaffolds, have been developed for the treatment of bone defects caused by trauma and/or infection. Among the materials used to manufacture scaffolds, 45S5 Bioglass is a bioceramic that arouses significant interest due to ease preparation and excellent bioactive response. Among the various processing methods cited in the literature for the production of bioactive glass scaffolds, gelcasting is a method that produces macroporous structures, with interconnected and spherical pores and high mechanical strength. However, in the literature there are few reports about bioactive glass scaffolds produced by gelcasting method. In this work, 45S5-BG scaffolds were produced by gelcasting of foams varying the amount of foaming agent in order to optimize the desirable characteristics of the scaffold. The scaffolds show porosity between 70 and 86% and compressive strength of 1.22?±?0.7 and 0.78?±?0.4 MPa. In the biological studies, all 45S5-BG scaffolds showed cytocompatibility towards human osteoblastic cells and bioactive properties using SBF assay. 相似文献
113.
Angélica?Ochoa-AvilésEmail author Roosmarijn?Verstraeten Lieven?Huybregts Susana?Andrade John?Van Camp Silvana?Donoso Patricia?Liliana?Ramírez Carl?Lachat Lea?Maes Patrick?Kolsteren 《Nutrition journal》2017,16(1):79
Background
In Ecuador, adolescents’ food intake does not comply with guidelines for a healthy diet. Together with abdominal obesity adolescent’s inadequate diets are risk factors for non-communicable diseases. We report the effectiveness of a school-based intervention on the dietary intake and waist circumference among Ecuadorian adolescents.Methods
A pair-matched cluster randomized controlled trial including 1430 adolescents (12–14 years old) was conducted. The program aimed at improving the nutritional value of dietary intake, physical activity (primary outcomes), body mass index, waist circumference and blood pressure (secondary outcomes). This paper reports: (i) the effect on fruit and vegetable intake, added sugar intake, unhealthy snacking (consumption of unhealthy food items that are not in line with the dietary guidelines eaten during snack time; i.e. table sugar, sweets, salty snacks, fast food, soft drinks and packaged food), breakfast intake and waist circumference; and, (ii) dose and reach of the intervention. Dietary outcomes were estimated by means of two 24-h recall at baseline, after the first 17-months (stage one) and after the last 11-months (stage two) of implementation. Dose and reach were evaluated using field notes and attendance forms. Educational toolkits and healthy eating workshops with parents and food kiosks staff in the schools were implemented in two different stages. The overall effect was assessed using linear mixed models and regression spline mixed effect models were applied to evaluate the effect after each stage.Results
Data from 1046 adolescents in 20 schools were analyzed. Participants from the intervention group consumed lower quantities of unhealthy snacks (?23.32 g; 95% CI: ?45.25,-1.37) and less added sugar (?5.66 g; 95% CI: ?9.63,-1.65) at the end of the trial. Daily fruit and vegetable intake decreased in both the intervention and control groups compared to baseline, albeit this decrease was 23.88 g (95% CI: 7.36, 40.40) lower in the intervention group. Waist circumference (?0.84 cm; 95% CI: ?1.68, 0.28) was lower in the intervention group at the end of the program; the effect was mainly observed at stage one. Dose and reach were also higher at stage one.Conclusions
The trial had positive effects on risk factors for non-communicable diseases, i.e. decreased consumption of unhealthy snacks. The program strategies must be implemented at the national level through collaboration between the academia and policy makers to assure impact at larger scale.Trial registration
ClinicalTrial.gov-NCT01004367.114.
Jorge Moiola Liliana Castro Hernán Cendra Alfredo Desages 《Dynamical Systems: An International Journal》1990,5(3):163-181
We present some bifurcation conditions using the well-known stability analysis of feedback systems. A general ordinary differential equation system is formulated in two parts: one that considers the linear part and the other that includes the memoryless nonlinear part, in a similar way as the describing function. The bifurcation conditions are obtained using the results of the generalized Nyquist stability criterion (GNSC) with some explicit formulae derived from some properties of the complex variable
We analyse simultaneously both static and dynamic (Hopf) bifurcations and their degeneracies in a rich example, a continuous stirred-tank reactor (CSTR), in which two consecutive, irreversible, first-order reactions A→B→C occur 相似文献
115.
H-ZSM-11 zeolite modified with zinc and gallium by ion exchange was investigated using XRD, IR and TPD of ammonia. The modification of the material by zinc produced a lowering of the strong Brønsted acidic sites generating new and strong Lewis sites. Unlike zinc-zeolites, the gallium is localized preferentially on the outer surface of microcrystallites blocking a few Brønsted centers. 相似文献
116.
Methane (C1) can be activated by interaction with liquefied petroleum gas (LPG) even at very high C1 molar fractions in the feed (C1/(C1 + LPG)=0.85) at temperatures of 450–550°C, GHSV(LPG)=2240 and 810 ml/g h, over Zn‐ZSM‐11 (molar fraction Zn2+/(Zn2+H+=0.86) and total pressure of 1 atm. The isobutane (i‐C4) of LPG could be the main responsible of this interaction. Aromatic hydrocarbons were the main products in the whole range
of C1 molar fractions (0.4–0.85) studied, reaching excellent levels of 10–45%.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
117.
Diogo A. B. Fernandes Liliana F. B. Soares João V. Gomes Mário M. Freire Pedro R. M. Inácio 《International Journal of Information Security》2014,13(2):113-170
In the last few years, the appealing features of cloud computing have been fueling the integration of cloud environments in the industry, which has been consequently motivating the research on related technologies by both the industry and the academia. The possibility of paying-as-you-go mixed with an on-demand elastic operation is changing the enterprise computing model, shifting on-premises infrastructures to off-premises data centers, accessed over the Internet and managed by cloud hosting providers. Regardless of its advantages, the transition to this computing paradigm raises security concerns, which are the subject of several studies. Besides of the issues derived from Web technologies and the Internet, clouds introduce new issues that should be cleared out first in order to further allow the number of cloud deployments to increase. This paper surveys the works on cloud security issues, making a comprehensive review of the literature on the subject. It addresses several key topics, namely vulnerabilities, threats, and attacks, proposing a taxonomy for their classification. It also contains a thorough review of the main concepts concerning the security state of cloud environments and discusses several open research topics. 相似文献
118.
119.
García-Alcaraz Jorge Luis Montalvo Francisco Javier Flor Sánchez-Ramírez Cuauhtémoc Avelar-Sosa Liliana Saucedo José Antonio Marmolejo Alor-Hernández Giner 《Wireless Networks》2021,27(3):1601-1614
Wireless Networks - This paper reports a structural equation model to relate three critical success factors for total quality management (TQM) (i.e. managerial commitment, role of quality... 相似文献
120.
Adina Maria Dobos Iuliana Stoica Niculae Olaru Liliana Olaru Emil Ghiocel Ioanid Silvia Ioan 《应用聚合物科学杂志》2012,125(4):2521-2528
The article describes some properties of cellulose acetates (CAs) with different substitution degrees. The hydrophilic/hydrophobic properties, morphological aspects, and interface properties with red blood cells and platelets are affected by the substitution degree, synthesis conditions, history of the formed films from solutions in acetone/water nonsolvent/nonsolvent mixtures, and low pressure plasma treatment. The results obtained are useful in biomedical applications, including evaluation of bacterial adhesion onto surfaces, or utilization of CA for semipermeable membranes. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献