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251.
Juan E. Gilbert Yolanda McMillian Ken Rouse Philicity Williams Gregory Rogers Jerome McClendon Winfred Mitchell Priyanka Gupta Idong Mkpong-Ruffin E. Vincent Cross II 《Universal Access in the Information Society》2010,9(4):357-365
Since the inception of elections and election technologies, all segments of the voting population have never been granted
equal access, privacy and security to voting. Modern electronic voting systems have made attempts to include disabled voters
but have fallen short. Using recent developments in technology a secure, user centered, multimodal electronic voting system
has been developed to study a multimodal approach for providing equity in access, privacy and security in electronic voting.
This article will report findings from a study at the Alabama Institute for the Deaf and Blind where more than thirty-five
blind or visually impaired participants used the multimodal voting system. The findings suggest that the proposed multimodal
approach to voting is easy to use and trustworthy. 相似文献
252.
Yolanda Blanco-Fernández José J. Pazos-Arias Alberto Gil-Solla Manuel Ramos-Cabrer Martín López-Nores Jorge García-Duque Ana Fernández-Vilas Rebeca P. Díaz-Redondo 《Journal of Systems and Software》2008,81(12):2371-2385
Current recommender systems attempt to identify appealing items for a user by applying syntactic matching techniques, which suffer from significant limitations that reduce the quality of the offered suggestions. To overcome this drawback, we have developed a domain-independent personalization strategy that borrows reasoning techniques from the Semantic Web, elaborating recommendations based on the semantic relationships inferred between the user’s preferences and the available items. Our reasoning-based approach improves the quality of the suggestions offered by the current personalization approaches, and greatly reduces their most severe limitations. To validate these claims, we have carried out a case study in the Digital TV field, in which our strategy selects TV programs interesting for the viewers from among the myriad of contents available in the digital streams. Our experimental evaluation compares the traditional approaches with our proposal in terms of both the number of TV programs suggested, and the users’ perception of the recommendations. Finally, we discuss concerns related to computational feasibility and scalability of our approach. 相似文献
253.
Maria Albareda-Sambola Elena Fernández Yolanda Hinojosa Justo Puerto 《Computers & Operations Research》2009
In this paper we introduce the multi-period incremental service facility location problem where the goal is to set a number of new facilities over a finite time horizon so as to cover dynamically the demand of a given set of customers. We prove that the coefficient matrix of the allocation subproblem that results when fixing the set of facilities to open is totally unimodular. This allows to solve efficiently the Lagrangean problem that relaxes constraints requiring customers to be assigned to open facilities. We propose a solution approach that provides both lower and upper bounds by combining subgradient optimization to solve a Lagrangean dual with an ad hoc heuristic that uses information from the Lagrangean subproblem to generate feasible solutions. Numerical results obtained in the computational experiments show that the obtained solutions are very good. In general, we get very small percent gaps between upper and lower bounds with little computation effort. 相似文献
254.
255.
Comparative subproteomic analysis of clinically acquired fluoroquinolone resistance and ciprofloxacin stress in Salmonella Typhimurium DT104B
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256.
Jakita O. Thomas Yolanda Rankin Rachelle Minor Li Sun 《Computer Supported Cooperative Work (CSCW)》2017,26(4-6):389-421
Computational algorithmic thinking (CAT) is the ability to design, implement, and assess the implementation of algorithms to solve a range of problems. It involves identifying and understanding a problem, articulating an algorithm or set of algorithms in the form of a solution to the problem, implementing that solution in such a way that the solution solves the problem, and evaluating the solution based on some set of criteria. CAT is an important scaffolded on-ramp as students develop more advanced computational thinking capabilities and apply computational thinking to solve problems that are more constrained and require greater expertise. Supporting Computational Algorithmic Thinking (SCAT) is both a longitudinal between-subjects research project and a free enrichment program supporting and guiding African-American middle school girls over three years as they iteratively design a set of complex games for social change. This article explores Scholars’ reflections about the difficulties they faced while using CAT capabilities as they engaged in collaborative game design for social change over those three years. We particularly focus on how these difficulties changed over the course of three years as well as new difficulties that emerged from year to year as Scholars become more expert game designers and computational algorithmic thinkers. 相似文献
257.
Desaturase activities in rat model of insulin resistance induced by a sucrose-rich diet 总被引:1,自引:2,他引:1
Brenner RR Rimoldi OJ Lombardo YB González MS Bernasconi AM Chicco A Basabe JC 《Lipids》2003,38(7):733-742
A sucrose-rich diet, as compared with a similar starch diet, induces a time-dependent typical noninsulin-dependent diabetes
syndrome characterized by insulin resistance in rats. Within the first 3 wk, there was glucose intolerance associated with
hyperinsulinemia, hypertriglyceridemia, and high plasma FFA. In this study, we examined the effect of the sucrose-rich diet
vs. the starch diet during short-(3 wk) and long-term treatment (6 mon) on hepatic Δ9, Δ6, and Δ5 desaturases. These enzymes
modulate monounsaturated FA and PUFA biosynthesis, respectively. Sucrose feeding (3 wk) caused an initial hyperinsulinemia
that was normalized within 6 mon. In the early period (3 wk), stearoyl-CoA desaturase-1 (SCD-1) mRNA and activity were decreased,
whereas Δ6 desaturase mRNA abundance and Δ6 and Δ5 desaturase activities remained unchanged. After 6 mon of sucrose feeding,
activities of the Δ9, Δ6, and Δ5 desaturases were each increased. The SCD-1 and Δ6 desaturase mRNA were also correspondingly
higher. These increases were consistent with an increase in oleic acid, the 20∶4/18∶2 ratio, and 22∶4n−6 and 22∶5n−6 acids
in liver and muscle lipids. On the other hand, the percentage of 22∶6n−3 acid was decreased. In conclusion, a sucrose-rich
diet after 6 mon induces an increase in rat liver SCD-1 and Δ6 desaturase mRNA and enzymatic activities that are opposite
to the changes reported in insulin-dependent diabetes mellitus. It appears that neither blood insulin levels nor insulin resistance
is a factor affecting the Δ9, Δ6, and Δ5 desaturase changes in mRNA and activity found with the sucrose-rich diet. 相似文献
258.
Pérez-Martínez P Pérez-Jiménez F Ordovás JM Moreno JA Marín C Moreno R Jiménez-Gómez Y Paniagua JA López-Miranda J 《Lipids》2007,42(2):143-150
Apolipoprotein (apoB) plays a fundamental role in the transport and metabolism of plasma triacylglycerols (TAGs) and cholesterol.
Several apoB polymorphic sites have been studied for their potential use as markers for coronary heart disease in the population.
In view of the importance of apoB in postprandial metabolism, our objective was to determine whether the presence of the -516C/T
polymorphism in the APOB gene promoter could influence postprandial lipoprotein metabolism in healthy subjects. Forty-seven volunteers who were homozygous
for the E3 allele at the APOE gene were selected (30 homozygous for the common genotype (C/C) and 17 heterozygotes for the
-516T allele (C/T). They were given a fat-rich meal containing 1 g fat and 7 mg cholesterol per kg body weight and vitamin
A 60,000 IU/m2 body surface. Fat accounted for 60% of calories, and protein and carbohydrates for 15 and 25% of energy, respectively. Blood
samples were taken at time 0, every 1 h until 6 h, and every 2.5 h until 11 h. Total cholesterol and TAGs in plasma, and cholesterol,
TAGs and retinyl palmitate in triacylglycerol-rich lipoproteins (large and small triacylglycerol-rich lipoproteins) were determined
by ultracentrifugation. Individuals carrying the C/T genotype presented greater postprandial concentrations of TAGs in small
triacylglycerol-rich lipoproteins than did carriers of the C/C genotype (P = 0.022). Moreover, C/T individuals presented higher concentrations of plasma TAGs during the postprandial period than did
C/C subjects (P = 0.039). No other statistically significant genotype-related differences for other parameters were observed. These results
suggest that the presence of the genotype C/T is associated with a higher postprandial response. Thus, the allele variability
in the -516C/T polymorphism in the APOB gene promoter may partly explain the interindividual differences in postprandial lipemic response in healthy subjects. 相似文献
259.
Torres-Dosal A Pérez-Maldonado IN Jasso-Pineda Y Martínez Salinas RI Alegría-Torres JA Díaz-Barriga F 《The Science of the total environment》2008,390(2-3):362-368
Indoor air pollution can be an important risk factor for human health, considering that people spend more than 60% of their time indoors. Fifty percent of the world population and approximately 90% of the rural population in developing countries are using biomass as energy source. Latin America represents 12% of the global consumption of biomass; in Mexico, 27 million people use wood as an energy source. Therefore, in this study we evaluated a 3-stage risk reduction program. The stages were: 1) removal of indoor soot adhered to roofs and internal walls; 2) paving the dirt floors; and 3) introduction of a new wood stove with a metal chimney that expels smoke outdoors. The complete intervention program was applied. In 20 healthy subject residents from an indigenous community in San Luis Potosí, Mexico, we measured blood carboxyhemoglobin (% COHb), DNA damage (comet assay) in nucleated blood cells, and urinary 1-OHP levels before and after the program. Before intervention individuals had a geometric mean COHb level of 4.93% and 53% of the population presented levels above 2.5% considered a safe level. However, in all the studied individuals the levels of COHb were reduced to below 2.5% (mean level 1.0%) one month after the intervention. Moreover, when compared, DNA damage in people exposed before the intervention was higher (5.8+/-1.3 of Tail Moment) than when the program was introduced (2.8+/-0.9 of Tail Moment) (P>0.05) and a same trend was observed with urinary 1-OHP levels; 6.71+/-3.58 micromol/mol creatinine was the concentration before intervention; whereas, 4.80+/-3.29 micromol/mol creatinine was the one after the program. The results suggest that the intervention program offers an acceptable risk reduction to those families that use biomass for food cooking. 相似文献
260.
Jorge Carlos Ruiz-Ruiz Yolanda Beatriz Moguel-Ordoñez 《Critical reviews in food science and nutrition》2017,57(12):2680-2690
The leaves of Stevia rebaudiana Bertoni has nutrients and phytochemicals, which make it an adequate source for the extraction and production of functional food ingredients. Preclinical and clinical studies suggest therapeutic and pharmacological applications for stevia and their extracts because they are not toxic and exhibit several biological activities. This review presents the biological activity of Stevia rebaudiana Bertoni and their relationship to antidiabetic, anticariogenic, antioxidant, hypotensive, antihypertensive, antimicrobial, anti-inflammatory and antitumor activities. Consumption and adverse effects were also reviewed. 相似文献