826 resultados para color difference formulas
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Abstract Apricot is one of the fruits dried by using different methods, such as sun, convective or microwave drying. The effects of drying methods on the components of this fruit differ depending upon the temperature or time parameters. In this research, the impacts of convective, microwave and microwave–convective drying techniques on color, β-carotene, minerals and antioxidant activity of apricots were investigated. The color values (L*, b*,ΔEab, h° and C*ab) of dried fruit were decreased, while the a* values increased. Compared with a fresh sample, the dried apricots showed a 1.4-3.9-fold proportional increase in β-carotene based on the increment of dry matter. The samples dried at high temperature and microwave levels, at 75 °C+90 watt and 75 °C+160 watt, showed lower antioxidant activity. Of the different drying treatments, the microwave-convective method (50 °C+160 watt) obtained a higher β-carotene content while maintaining antioxidant activity with a short drying time.
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Coffee seeds have slow and irregular germination, losing fast their viability during storage, and the standard germination test of these seeds requires at least 30 days. Besides, the results may not reflect the actual physiological quality of these seeds. The objective of this work was to develop a fast and practical test for evaluating the viability of coffee seeds, which is based on the interpretation of different color hues of exudates from seeds. Coffee seeds of the cultivar Catuai 44 from six lots were submitted to germination, accelerated aging, and electrical conductivity tests. In the exudates color hue test, coffee seeds without the parchment and the silvery pellicle (four replications of 10 seeds each) were distributed on top of paper towels moistened and then maintained into a germinator, at 25 ºC for 24, 48, 72, 96, and 120 h. Three classes of color hues were established: colorless, light color hue, and dark color hue, assigning the values of 0, 1, and 3, for each class, respectively. The proposed exudates color hue test can be recommended for the fast assessment of viability for coffee seeds. The most promising results were obtained for seeds with 12% moisture content, after imbibition periods of 72, 96, and 120 h; and with 30% moisture content, after imbibition periods of 72 and 120 h.
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Hydrogen (H2) fuel cells have been considered a promising renewable energy source. The recent growth of H2 economy has required highly sensitive, micro-sized and cost-effective H2 sensor for monitoring concentrations and alerting to leakages due to the flammability and explosiveness of H2 Titanium dioxide (TiO2) made by electrochemical anodic oxidation has shown great potential as a H2 sensing material. The aim of this thesis is to develop highly sensitive H2 sensor using anodized TiO2. The sensor enables mass production and integration with microelectronics by preparing the oxide layer on suitable substrate. Morphology, elemental composition, crystal phase, electrical properties and H2 sensing properties of TiO2 nanostructures prepared on Ti foil, Si and SiO2/Si substrates were characterized. Initially, vertically oriented TiO2 nanotubes as the sensing material were obtained by anodizing Ti foil. The morphological properties of tubes could be tailored by varying the applied voltages of the anodization. The transparent oxide layer creates an interference color phenomena with white light illumination on the oxide surface. This coloration effect can be used to predict the morphological properties of the TiO2 nanostructures. The crystal phase transition from amorphous to anatase or rutile, or the mixture of anatase and rutile was observed with varying heat treatment temperatures. However, the H2 sensing properties of TiO2 nanotubes at room temperature were insufficient. H2 sensors using TiO2 nanostructures formed on Si and SiO2/Si substrates were demonstrated. In both cases, a Ti layer deposited on the substrates by a DC magnetron sputtering method was successfully anodized. A mesoporous TiO2 layer obtained on Si by anodization in an aqueous electrolyte at 5°C showed diode behavior, which was influenced by the work function difference of Pt metal electrodes and the oxide layer. The sensor enabled the detection of H2 (20-1000 ppm) at low operating temperatures (50–140°C) in ambient air. A Pd decorated tubular TiO2 layer was prepared on metal electrodes patterned SiO2/Si wafer by anodization in an organic electrolyte at 5°C. The sensor showed significantly enhanced H2 sensing properties, and detected hydrogen in the range of a few ppm with fast response/recovery time. The metal electrodes placed under the oxide layer also enhanced the mechanical tolerance of the sensor. The concept of TiO2 nanostructures on alternative substrates could be a prospect for microelectronic applications and mass production of gas sensors. The gas sensor properties can be further improved by modifying material morphologies and decorating it with catalytic materials.
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Desarrollo empresarial y creación de empresa
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Desarrollo empresarial y creación de empresa
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Existing research on attraction to body features has suggested that men show general preferences for women with lower waist-to-hip ratios (WHR), larger breasts, and slender body weights. The present study intended to expand on this research by investigating several individual difference factors and their potential contribution to variation in what men find attractive in female body features. Two hundred and seventy-three men were assessed for sex-role identity, 2D:4D digit ratios (a possible marker of prenatal exposure to androgens, and thus masculinization), physical attractiveness, early sexual experiences (as indices of early sexual conditioning), and early family attitudes toward body features, as well as their current preferences for WHR, breast size, weight, and height in women. For WHR, as predicted, physical attractiveness, early sexual experiences, and lower (more masculine) right-hand 2D:4D ratios significantly predicted current preferences for more feminine (lower) WHR. Early sexual experiences significantly predicted later preferences for breast size; in addition, more masculine occupational preferences and lower (more masculine) left-hand 2D:4D ratios predicted preferences for larger breasts. Participants' height, education level, Unmitigated Agency (masculinity) scores, and early sexual experiences significantly predicted current preferences for height. Finally, early sexual experiences significantly predicted current preferences for weight. The results suggest that variation in preferences for women's bodily features can be uniquely accounted for by a number of individual difference factors. Strengths and weaknesses of the study, along with implications for future research, are discussed.
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One hundred and five primarily Caucasian undergraduate couples were tested to study the phenomenon of attitude alignment, or the way in which individuals change their opinions to achieve greater attitudinal congruence with their romantic partners, and the hypotheses that relationship closeness, affect, attachment, social desirability, and centrality are each related to attitude alignment for individuals in close couples. The couples filled out an attitude questionnaire consisting of 50 issues in which they were asked to give their attitude on a scale from 1 to 9 as well as to rate the centrality, or importance, of that issue on a scale from 1 to 9. Before discussing four of these issues with each other - 2 were more central to the man and less central, or peripheral, to the woman, whereas the other 2 were central to the woman and peripheral to the man - the individuals completed established measures of relationship closeness, affect, attachment, and social desirability. The couples then filled out the identical attitudes questionnaire again, and their answers on the four discussion issues were compared to their prediscussion answers to determine whether attitude alignment had occurred. There were two experimental groups: a social desirability group, where the couples were told it was natural and normal to disagree with their partners, and a control group. Results indicated that attitude alignment did significantly occur across all couples, but most other variables - including centrality, relationship closeness, and affect - did not predict attitude alignment behaviour. As well, the social desirability experimental groups did not significantly differ on attitude alignment behaviours, but higher scores on the social desirability scale, specifically self-deception, significantly predicted higher attitude alignment scores across all couples. Large differences between individuals' frequency.
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This study explores how new university teachers develop a teaching identity. Despite the significance ofteaching, which usually comprises 40% of a Canadian academic's workload, few new professors have any formal preparation for that aspect of their role. Discipline-specific education for postsecondary professors is a well-defined path; graduates applying for faculty positions will have the terminal degree to attest to their knowledge and skill conducting research in the discipline. While teaching is usually given the same workload balance as research, it is not clear how professors create themselves as teaching professionals. Drawing on Kelly's (1955) personal construct theory and Kegan's (1982, 1994) model ofdevelopmental constructivism through differentiation and integration, this study used a phenomenographic framework~(Marton, 1986, 1994; Trigwell & Prosser, 1996) to investigate the question of how new faculty members construe their identity as university teachers. Further, my own role development as researcher was used as an additional lens through which to view the study results. The study focused particularly on the challenges and supports to teaching role development and outlines recommendations the participants made for supporting other newcomers. In addition, the variations and similarities in the results suggest a developmental model to conceptions ofteaching roles, one in which teaching, research, and service roles are viewed as more integrated over time. Developing a teacher identity was seen as a progression on a hierarchical model similar to Maslow's (1968) hierarchy of needs.
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Recent Ontario legislation by the Ministry of Education has targeted a goal of 50 percent as the minimum objective for representation by women in positions of responsibility by the year 2000. As a result,those few women currently in the field of Educational Administration have become a focus for researchers. The intent of this research is to contribute to the current knowledge and understanding of women principals in the leadership role. In-depth interviews with four experienced female principals were conducted centering on their perceptions and experiences on a wide range of issues that included: gender characteristics and impact on role, perceived differences as a result of gender characteristics, decision making, curriculum leadership, communication, the perception of others, and the advantages and disadvantages of being a woman in the role. Narrative profiles were constructed for each participant and analyzed. A description for each woman emerged by an analysis of common patterns and themes in the participants' narratives. Results revealed that the participants were able to identify and to describe particular gender traits that they perceived had impact on their role. Moreover the participants regarded their gender characteristics as facilitating and enhancing the performance of their role. Common patterns for all the participants emerged from the data that conveyed a strong feminine imagery of mother and espoused the idea of school as home, and staff and students as family. Leadership ii styles demonstrated an emphasis on collaborative decision making, open communication, and apparent difficulty and ambiguity arising from the role of Curriculum leader. The results of this study also indicate that personal metaphors ascribed and embedded in the narratives are significant in conceptualizing and interpreting the administrative role.
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The purpose of this project was to identify in a subject group of engineers and technicians (N = 62) a preferred mode of representation for facilitating correct recall of information from complex graphics. The modes of representation were black and white (b&w) block, b&w icon, color block, and color icon. The researcher's test instrument included twelve complex graphics (six b&w and six color - three per mode). Each graphics presentation was followed by two multiple-choice questions. Recall performance was better using b&w block mode graphics and color icon mode graphics. A standardized test, the Group Embedded Figures Test (GEFT) was used to identify a cognitive style preference (field dependence). Although engineers and technicians in the sample were strongly field-independent, they were not significantly more field-independent than the normative group in the Witkin, Oltman, Raskin, and Karp study (1971). Tests were also employed to look for any significant difference in cognitive style preference due to gender. None was found. Implications from the project results for the design of visuals and their use in technical training are discussed.
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In light of the fact that literature on toxicity of heavy metals in non-acidified
freshwater systems is sparse, this project was initiated to conduct an environmental
assessment of Lake Gibson. Chemistry of soils from adjacent areas and vineyards in the
region provide a comparative background database. Water quality determinations were used
to identify and highlight areas of environmental concern within the Lake Gibson watershed.
A Shelby Corer was used to obtain 66 sediment cores from Lake Gibson. These were
sectioned according to lithology and color to yield 298 samples. A suite of 122 soil samples
was collected in the region and vicinity of Lake Gibson. All were tested for metals and
some for Total Petroleum Hydrocarbons (TPH). Evaluation of the results leads to the
following conclusions:
1. Metal concentrations ofAI, Cd, Cu, Cr, Pb, Ni, Fe and Zn in soils from the Niagara
Region are well below background limits set by the Ministry of the Environment
and Energy (MOEE) for provincial soils.
2. There is a spatial and depth difference for some of the metals within the various
soils. The Cr, Ni and Pb contents of soils vary throughout the region (p
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Research and practice regarding LO students usually has focussed upon defining and supplementing deficiencies rather than seeking unique talents and capability patterns for learning and expression. This study examined nine dimensions that may constitute artistic or creative talent and compared LDs with "regular-class" students, pair-wise and as groups, for levels and distributions of the dimensions. For 14 LO and 9 "regular-class" elementary-school subjects, both genders, data were taken by direct observation, from a standardized test and assessments by two practicing artists. Assessments by artists were in concord. LOs improved more in "Composition". No other significant class, age or gender-related differences were found.
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This qualitative study explores practicing teachers' experiences of teaching in classrooms of diversity, that is, classrooms where students represent a variety of differences including race, culture, ethnicity, and class. More specifically, this study investigates the types of curricular and pedagogical practices teachers employ in their classrooms. This study attempts to make a contribution to the scholarship of critical pedagogy by drawing upon the works of critical pedagogues to make sense of participants' descriptions oftheir curricular and pedagogical practices. Four participants were involved in this study. Participants were elementary teachers in classrooms of difference in Ontario who contributed the primary sources of data by engaging in 2 individual interviews. Additional sources of data included a focus group meeting that 2 ofthe participants were able to attend, school board curriculum resource documents assisting teachers in teaching critically, as well as a research journal which the researcher kept throughout the study. The scholarship of critical pedagogy (Ellsworth, 1992; Giroux, 1993; McLaren, 1989) informs the analysis of participants' descriptions of their teaching experiences. Many of the participants did not engage in a practice of critical pedagogy. This study explores some of the challenges and possibilities of using critical pedagogy to create spaces in classrooms where teachers can build connections between the curriculum mandated by the government and the multiple identities and experiences that students bring into the classroom. This study concludes with a discussion on what teachers need to know to be able to begin creating equitable and educational experiences in classrooms of difference.
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Self-presentation reflects the processes by which individuals attempt to monitor and control the impressions others form of them (Schlenker & Leary, 1982). Concerns over impressions conveyed have been linked to numerous health behaviors (Crawford & Eklund, 1994; Martin, Leary, & O'Brien, 2001). The present study investigated the role of cognitive manifestations of dispositional and situational self presentational motivation (SPM) in 131 females with known groups differences on a measure of eating disorders. Participants were classified as in-treatment (IN = 39); at risk (AT = 46); and not at risk (NOT = 46) for eating disordered behaviour. Each participant completed The Brief Fear of Negative Evaluation Scale (FNE; Leary, 1983), the Public Self-Consciousness Scale (PSC; Fenigstein, Sheier, & Buss, 1975), and the Social Physique Anxiety Scale (SPA; Hart, Leary, & Rejeski, 1989), as measures of dispositional SPM. Situational SPM was assessed through Self-Presentational Efficacy (SPE; Gammage, Hall, & Martin, 2004), and the Exercise Motivation Inventory-2 (Markland & Ingeldew, 1997). Significant differences emerged on the measure of eating disorder behaviour between AT and NOT. To determine if group differences existed on measures of trait SPM an ANOVA was conducted. Results indicated that the NOT group experienced less FNE, PSC and SPA than the IN and AT groups, and the AT group experienced less FNE and PSC than the IN group. Pearson bivariate correlations were conducted on measures of trait SPM and EMI-2 subscales theoretically linked to SPM. It was found that FNE, PSC and SPA were all positively correlated with weight management for the NOT group. To determine if group differences existed on selfpresentational exercise motives independent samples I-tests were conducted. Results revealed that the AT group was more motivated to exercise for weight management, and appearance, and social recognition than the NOT group. To determine if group differences existed on the state measure of self-presentational efficacy a series of ANOVA's were conducted. Results revealed that the NOT group experienced significantly greater self-presentational efficacy expectancy and self-presentational outcome value than the AT group. Finally, a discriminant function analysis was conducted to determine if trait SPM would predict group membership. Results revealed that 63.4% of participants were correctly classified, with SPA, PSC, and FNE differentiating the NOT group from the AT and IN groups and FNE and PSC differentiating the AT group from the IN group. Thus self-presentation motivation appears to have an influence on females who have an eating disorder and those at risk for an eating disorder. Potential applications of the influence of self-presentational motives on eating disorders and future research directions are discussed.