Effect of Gaseous Ozone on Antioxidant Content and Color of Sliced Tomatoes

Sliced tomatoes are used frequently in restaurants and fast-food establishments. Their limited shelf-life has caused scientists to study treatments to prolong their useful life. Previously, treatments for shelf-life extension have included mild heat treatment and modified atmosphere packaging. Although gaseous ozone has been shown to reduce spoilage microorganisms on produce, limited research has been performed regarding the oxidation potential of ozone on antioxidant compounds. Our objective was to evaluate the effect of gaseous ozone on lycopene and ascorbic acid in sliced tomatoes, as well as its effect on tomato color. Two tomatoes of uniform size and color (USDA Stage 5) were cut into cross-sectional slices. Quart-size wide mouth sterilized Mason jars covered in aluminum foil were used as treatment vessels. Jars containing tomato slices and 1 mL aliquots of 24-h tomato spoilage culture were treated with ozonated air at treatment levels of 0, 90, 105, 120, and 135 min. Lycopene was extracted with solvent containing hexane:methanol:acetone, and absorbance of the samples was read in a spectrophotometer at 503 nm against a hexane blank. Lycopene content was calculated for each sample using a mathematical formula. A 2,6-dichloroindophenol titrimetric method was used for ascorbic acid determination. Color measurements were performed on ground tomato samples. All experiments were statistically analyzed using the mixed procedure (PROC MIXED) of SAS version 8.1 (SAS Institute, Cary, NC). Means were separated using Tukey\u27s mean separation test. Significant differences were defined at P0.05) in lycopene content were found between untreated tomato slices or slices treated for 90, 105, 120, or 135 minutes. The ascorbic acid content of sliced tomatoes treated with gaseous ozone for 135 minutes was significantly lower (p 0.05) than untreated sliced tomatoes. No significant differences (p\u3e0.05) were found in Hunter L, a, or b values between untreated tomato slices or slices treated for 135 minutes. Aerobic plate counts of spoilage microorganisms treated with gaseous ozone for times of 105, 120, and 135 minutes were statistically similar to each other, but all were significantly lower than untreated samples. Aerobic plate counts of samples treated for 90 minutes were not statistically different from either untreated samples or samples treated for 105, 120, or 135 minutes. Results indicate that gaseous ozone treatment for a minimum of 105 minutes can be an effective means of decreasing spoilage microflora of sliced tomatoes. Lycopene and color measurements do not seem to be adversely affected, but ascorbic acid may be significantly reduced. Therefore, ozone treatments to reduce microbial loads may not be appropriate for fresh-cut produce items that are consumed to provide ascorbic acid in the diet

Repurposing resources as open content: studying the experiences of new providers

Much educational content sits within institutional systems protected from global access, this proprietary approach restricts opportunities for informal learning and the exchange of materials between cultures. One response to reducing this particular digital divide is to open up access to existing courses by providing them as free to use Open Educational Resources (OERs). This is being addressed through work on OpenLearn (the open content initiative from The Open University developed with support from the William and Flora Hewlett Foundation) and POCKET (The Project on Open Content for Knowledge Exposition and Teaching, supported by JISC under the repositories and preservation programme). The approach is evaluative considering transfer of lessons from work on the reworking of distance learning materials (within the OpenLearn initiative) to the reworking of material from campus-based universities (supported by the POCKET project). Analysis will include the role of supporting artifacts (guidelines, examples, tools) and the process support required (shared aims, workshops, structure). Evaluation tools that are being applied include logging of experience, stake holder interviews, and analytics data. We are building on existing evaluation of the OpenLearn initiative that has revealed models for learner use of open educational resources and studied the reuse of released open resources. Results include the need for a range of reworkable formats, support and time pressures on voluntary use – these results are supported by case study information and overall usage statistics. Further data that will be available from POCKET by September 2008 will include reflections from participants, workshop outcomes and initial stakeholder interviews, full evaluation of POCKET will be complete by April 2009. This paper will have examined our understanding of the process by which content can be transformed from existing learning materials to freely available open educational resources. Conclusions at this stage will focus on the process of adoption and transfer from OpenLearn and the effectiveness of the evaluation and project approach. Comparison will be made with the advantages and disadvantages of the self supported approach adopted initially in OpenLearn and suggestions given for structures that enable collaboration in producing open educational resources

Adolescent Depressive Symptoms and Substance Use: The Mediating Influence of Health Service Utilization

A large number of American adolescents suffer from depression and the consequences have been shown to be detrimental to their well-being. Adolescent substance use is also an increasing social problem due to the high usage rates and negative lifelong consequences for users. This paper explores the relationships between victimization, substance use, psychological health service utilization, and depressive symptoms in a sample of 4,757 adolescents. Using two waves of data from the National Longitudinal Study of Adolescent Health (Add Health), the results revealed a positive relationship between victimization and adolescent depressive symptoms, even after controlling for several demographic variables and previous depressive symptoms. However, victimization was only moderately associated with depressive symptoms, indirectly through cigarette or marijuana use. Moreover, psychological health service utilization partially mediated the significant association between adolescent substance use (cigarette or marijuana) and adolescent depressive symptoms. In conclusion, adolescents who experience higher levels of victimization may be more likely to use cigarettes or marijuana, which is positively associated with utilizing psychological health services, thereby elevating the risk of adolescent depressive symptoms. Intervention to reduce adolescent substance use may reduce vulnerability to adolescent depressive symptoms. Advisor: Kimberly A. Tyle

What is preventing e-commerce from reaching its full potential? An investigation into trust as a barrier for the adoption of B2C e-commerce in the United Kingdom

Although electronic commerce has seen considerable growth in recent years, usage figures suggest that U.K consumers are still hesitant to make the switch to onJine shopping. This study initially reviewed the literatures on trust, Internet security, consumer purchasing behaviour and electronic commerce, and then combined the literature review findings with initial results obtained from a pilot study, and a model identifying the factors that affect consumers' perceived trustworthiness of web sites when making purchasing decisions on the Internet was created. The model was then tested by means of a consumer perception survey that used a novel quantitative survey instrument to investigate current consumer perceptions of e-commerce, from the perspective of both Internet and Non Internet users, and determined the main barrier to business to consumer (B2C) electronic commerce as identified by the potential consumers themselves. These quantitative findings were then used to further develop the model of trust, encompassing all the potential factors that the research identified could impact on a consumer's perceived level of trust in a web site, thus ultimately affecting their decision to purchase. This model was then tested through further qualitative research that incorporated observational studies to test consumer reactions to an onJine shopping scenario, using a special selection of web sites that should have (based on the model) a positive or negative influence on consumers' trust. Although the research design was qualitative in nature, a triangulation approach was adopted to ensure that the information generated was highly relevant and directly applicable to the creation of a model of trust. The model was revised, with the final version named the Model of Factors Affecting Consumer Trust Online (M.O.F.A.C.T.O). The implications of the model and recommendations for further research are discussed

The families of seventeen runaway children seen at the Worcester Youth Guidance Center.

Thesis (M.S.)--Boston Universit

Hazard Perception, Presence, and Simulation Sickness—A Comparison of Desktop and Head-Mounted Display for Driving Simulation

Driving simulators are becoming increasingly common in driver training and assessment. Since virtual reality is generally regarded as an appropriate environment for measuring risk behavior, simulators are also used to assess hazard perception, which is considered to be one of the most important skills for safe driving. Simulators, which offer challenges that are indeed comparable to driving in real traffic, but at a very low risk of physical injury, have the potential to complement theoretical and practical driver trainings and tests. Although configurations and fidelity differ considerably between driving simulators, studies comparing the impact of their distinct features on driving performance and test validity remain rare. In this context, prior research demonstrated that a wider field of view (three monitors compared to a single monitor) led to earlier speed adjustments in response to potential hazards—especially for experienced drivers. The wider field of view was assumed to cause the drivers to be more present in the virtual world, which in turn provoked more natural scanning of the road and therefore, earlier hazard detection in experienced drivers. Research on spatial presence in other contexts support this assumption. The present experiment investigated whether this effect could be enhanced by an even more immersive presentation technique for driving simulation: a head-mounted display (HMD). Moreover, we studied the interplay between display mode, sense of presence and simulation sickness. Eighty experienced and less experienced drivers completed six simulation-based hazard perception scenarios, which were displayed either via a triple-monitor set-up or an HMD. Results indicate that the experienced drivers showed very similar driving and risk behavior as the inexperienced drivers in both experimental conditions. However, there were significant differences between the two display conditions. The use of an HMD resulted in a clearer and more abrupt speed reduction, more virtual presence, and a higher degree of simulation sickness. However, the interrelation between these three variables could not be conclusively clarified in the present study and thus represents a research aim that could be addressed in future studies

Citizen Volunteers in Prison: Bringing the Outside in, Taking the Inside out

The United States correctional system relies heavily on citizen volunteers, but there is little contemporary research on prison volunteers, which is further limited by sample and geographic region. The purpose of this project was to explore the role of citizen volunteers, including investigating why they volunteer and what their experiences with inmates and prison staff are like. Semi-structured interviews were conducted with citizen volunteers in the penal system of a Midwestern state. Volunteers had altruistic or faith-based motivations, viewing themselves as ‘seed planters’ but not saviors, and placing priority on building relationships. They described how volunteering transformed their views on inmates and the prison system. Volunteers appeared to gain awareness of and appreciation for the problems associated with both serving time and reentry. Additional research on the role of citizen volunteers is needed to improve recruiting and retention of volunteers, and to better evaluate and develop programs for current and reentering inmates

Building Effective Community Partnerships

Community Engagement H2O (CE-H2O) is a faith-based student organization that works to serve the community in the Columbus area. This student organization leverages building effective community partnerships with motivating and equipping university teams to advance the health and wellness of four key demographics in the Columbus area. These four communities are the immigrant and refugee population, those suffering in poverty, the orphan population and the widow population. CE-H2O has been effectively equipping university teams to lead community service projects in Columbus for more than five years and has created a model for sustainable, volunteer-based community engagement through a foundation in shared motivation with partner organizations. To create enduring and impactful community partnerships, a shared motivation is needed between the university teams and partnership organizations. For CE-H2O, this shared motivation comes from faith-based motivations for serving the community out of a genuine care for the health and well-being of those in need. CE-H2O is partnered with organizations that serve communities in Columbus through medical clinics, education, hunger relief and human-trafficking abolition. CE-H2O connects student lead university teams with these community partners to promote the health and wellness of these communities. Team development is paramount in maintaining these partnerships, and CE-H2O works diligently to foster growth and leadership in the university teams. Leadership preparation involves monthly CE-H2O meetings in which partnership events are organized; and leaders volunteer to liaison with partner organization to plan and prepare the student teams for the community engagement events. The leaders work to prepare university teams by connecting students to the community partners and lead teams through community engagement events. Student participants have multiple choices in serving with the community partners listed previously. This diversity enables the student to match their passions with the passions of a community partner, which promotes enduring relationships between the students and community partners. Team leaders hold briefings before and after each event to prepare teams for the event and inspire participants to become further involved in community engagement. This presentation is intended for organizations and administrators wanting to learn a sustainable model for creating community partnership with university teams. This presentation is also intended for students seeking community engagement partnerships. The individuals giving this presentation have expertise including more than five years of building effective community partnerships in Columbus, two years of being a student leader for university teams fostering these community relationships, and six months of direct internship experience with a community partner.AUTHOR AFFILIATION: Mike Malone, Pastor, CE-h2o, [email protected] (Corresponding Author); Megan Luthie, Student, CE-h2o; Sarah Stewart, Student, CE-h2o; Daniel Richie, Graduate Teaching Associate, Mechanical and Aerospace Engineering.Community Engagement h2o (CE-h2o) is a faith-based student organization that works to serve the community in the Columbus area. This student organization leverages building effective community partnerships with motivating and equipping university teams to advance the health and wellness of four key demographics in the Columbus area. These four communities are the immigrant and refugee population, those suffering in poverty, the orphan population, and the widow population. To create enduring and impactful community partnerships, a shared motivation is needed between the university teams and partnership organizations. This shared motivation creates enduring relationships between the university teams and community partners, and it promotes lifelong community engagement. This information is intended for students seeking community partnerships, as well as those wanting to learn a sustainable model for creating community partnership with university teams

Homogeneous and heterogeneous multiple representations in equation‐solving problems: An eye‐tracking study

Multiple external representations (MERs) play an important role in the learning field of mathematics. Whereas the cognitive theory of multimedia learning and the integrative text and picture comprehension model assume that the heterogeneous combination of symbolic and analogous representations fosters learning; the design, functions, and tasks framework holds that learning benefits depend on the specific functions of MERs. The current paper describes a conceptual replication study of one of the few studies comparing single representations, heterogeneous, and homogeneous MERs in the context of mathematics learning. In a balanced incomplete block design, the participants were provided single representations (a graphic, text, or formula) or a heterogeneous (e.g., text + graphic) or homogeneous (text + formula) combination of these to solve linear system of equations problems. In accordance with previous research, performance was superior in conditions providing MERs compared to single‐representation conditions. Moreover, heterogeneous MERs led to time savings over homogeneous MERs which triggered an increase in cognitive load. Contrary to previous research, text was the least fixated representation whereas the graphical representation proved to be most beneficial. With regard to practical implications, experts should be fostered through more challenging homogeneous MERs whereas novices should be supported through the accessible graphic contained in heterogeneous MERs

Turning educational content into open content: a workshop

The POCKET project is building on the infrastructure provided by the Open University’s OpenLearn open educational repository. POCKET, the Project on Open Content for Knowledge Exposition and Teaching, is led by the University of Derby and partnered by The Open University, the University of Exeter and the University of Bolton. The POCKET project is designed to leverage what has already been invested in OpenLearn and extend Open Educational Resource (OER) activity to other universities. The workshop will involve the audience in considering how they would develop OERs in practice in their own institutions. The session will start with the theme of matching technology with the pedagogy of OERs, followed by each of the four institutions briefly discussing how they have developed and had to rethink the design of their materials into OERs. This will include a showcase of the resulting OERs. In the main part of the workshop the participants will be invited to consider which approach would suit their institution best and take part in activities designed to take them through the process