304 research outputs found
Microwave extraction of essential oils (from black pepper and coriander) at 2.46 GHz
Essential oils are composed of a wide range of bioactive chemical compounds. They traditionally found application as flavour, fragrances and medicinal aroma. Today, the essential oils are sought-after for innumerable applications starting from markers for plant identifications to base for semi-synthesis of highly complex molecules. The extraction of highly delicate essential oils from plants remains a crucial step in all these applications. By using microwaves to mediate the extraction, it is possible to maintain mild conditions and effect superior extraction. However, apart from laboratory trials, essential oil extraction using microwave energy is largely an unexplored area. In the current work, an integrated procedure for microwave extraction followed by volatiles sampling and analysis from selected botanical raw materials (viz. black pepper, Piper nigrum and coriander Coriandrum sativum) was developed. There are two problems to overcome in the extraction from solid plant materials: that of releasing the essential oil from solid matrix and letting it diffuse out successfully in a manner that can be scaled-up to industrial volumes. Towards this end, an innovative volatiles extraction unit was conceived, designed and developed that used thin layer, for microwave exposure and rotational mixing, to mitigate the effects of thermal gradient and non-uniform exposure of bulk matter.
The effect of varying the microwave field on the essential oils extracted was studied. The microwave field that coupled in the region of extraction was estimated from temperature rise measurement using the microwave power equation (with water as reference dielectric). The essential oil extracted under different microwave fields were compared using gas chromatography-mass spectrometry (GC-MS) and data analysis with SAS statistical software.
The microwave field at the site of extraction was sensed by symmetrical placement of biomaterial sample and a reference, in a rotational extractor, such that they both couple the same field during tumbling motion. By measuring the temperature rise in the reference accurately, it is possible to estimate the microwave field present at that position. The rotational extractor has a second degree of freedom, in that it can slide along the axel taking discrete positions. Each position leads to a different microwave exposure of the sample. It is possible to measure the relative variation of microwave field using temperature rise data at each position. It was found that, at position labeled R4, located at 65.6 mm from the right extreme of the microwave cavity had the highest effective microwave field strength of value 92.7 V/m.
The volatiles released from the biomaterials, black pepper and coriander, were sampled using solid phase micro extraction and analyzed using gas chromatography-mass spectrometry. The highest peaks representing beta-caryophyllene in black pepper and linalool in coriander were identified using mass spectrometric peak matching using NIST library.The extract (in terms of ion count) for each microwave parameter (such as field, water content level and solvent type) was plotted as a trend graph.
The current experiment successfully tested the procedure for following the microwave process in the extraction of sensitive spice volatiles (from black pepper and coriander). With the microwave field measured at the region of extraction, it was possible to plot pepper extraction versus the microwave field to which the pepper sample was exposed. The extraction was represented in terms of cumulative value of ion counts obtained in GC-MS analysis. This unique procedure developed in the current research allows for the graphical comparison of the microwave extractions. It was found that black pepper has a better response to microwave extraction than coriander. The pepper extraction was found to increase proportionately with increase in microwave field strength. The extraction was also enhanced proportionately by the incremental addition of water content at constant microwave field
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Social media use by community-based organizations conducting health promotion: a content analysis
Background: Community-based organizations (CBOs) are critical channels for the delivery of health promotion programs. Much of their influence comes from the relationships they have with community members and other key stakeholders and they may be able to harness the power of social media tools to develop and maintain these relationships. There are limited data describing if and how CBOs are using social media. This study assesses the extent to which CBOs engaged in health promotion use popular social media channels, the types of content typically shared, and the extent to which the interactive aspects of social media tools are utilized. Methods: We assessed the social media presence and patterns of usage of CBOs engaged in health promotion in Boston, Lawrence, and Worcester, Massachusetts. We coded content on three popular channels: Facebook, Twitter, and YouTube. We used content analysis techniques to quantitatively summarize posts, tweets, and videos on these channels, respectively. For each organization, we coded all content put forth by the CBO on the three channels in a 30-day window. Two coders were trained and conducted the coding. Data were collected between November 2011 and January 2012. Results: A total of 166 organizations were included in our census. We found that 42% of organizations used at least one of the channels of interest. Across the three channels, organization promotion was the most common theme for content (66% of posts, 63% of tweets, and 93% of videos included this content). Most organizations updated Facebook and Twitter content at rates close to recommended frequencies. We found limited interaction/engagement with audience members. Conclusions: Much of the use of social media tools appeared to be uni-directional, a flow of information from the organization to the audience. By better leveraging opportunities for interaction and user engagement, these organizations can reap greater benefits from the non-trivial investment required to use social media well. Future research should assess links between use patterns and organizational characteristics, staff perspectives, and audience engagement
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Effect of Media Use on HIV-Related Stigma in Sub-Saharan Africa: A Cross-Sectional Study
It is known that HIV-related stigma hinders prevention efforts. Previous studies have documented that HIV-related stigma may be associated with socioeconomic and socioecological factors. Mass media use may moderate this association, but there is limited research addressing that possibility. In this study, based on cross-sectional data pooled from the 2006–2011 Demographic and Health Surveys of 11 sub-Saharan African countries (N = 204,343), we investigated the moderating effects of exposure to mass media on HIV-related stigma. Hierarchical regression analysis indicated that HIV-related stigma tends to be higher among rural residents and individuals with low levels of education and HIV knowledge, as well as those who do not know people living with HIV. Media use was generally associated with low levels of HIV-related stigma, and attenuated the gap between individuals with high and low educational levels. However, the effect of mass media was found to be stronger among urbanites rather than among rural residents, which could lead to a widening gap between the two groups in endorsement of HIV-related stigma. The implication of this study regarding the effect of media use on HIV-related stigma in sub-Saharan Africa is twofold: 1) mass media may have the potential to minimize the gap in HIV-related stigma between individuals with high and low educational levels, and hence future efforts of reducing HIV-related stigma in the region may benefit from utilizing media; 2) due perhaps to low media penetration to rural sub-Saharan Africa, mass media could have the unintended effect of widening the urban-rural gap further unless other more customized and rural-focused communication interventions are put in place
PLANET MassCONECT – Community-engaged Capacity-building Around Evidence-based Programs: Key Takeaways
PLANET MassCONECT was a community-based participatory research project (CBPR) conducted by investigators from the Dana-Farber Cancer Institute / Harvard T.H. Chan School of Public Health, in collaboration with partners from Boston, Lawrence and Worcester. The goal of the project, which was conducted from 2008-2013 was to use a CBPR approach to develop and implement a capacity-building program to train staff of community-based organizations to find, adapt, use, and evaluate evidence-based programs. The Institute for Community Health Planning (iCHPP) provided training workshops (typically over two half-day sessions), a dedicated website with localized resources and materials to support the systematic approach to program planning, networking events and mini-grants for alumni. We trained a total of 179 practitioners in the three main communities, as well as 65 in Brockton and Lowell. This assessment focuses on data from Boston, Lawrence, and Worcester.
Here, we present an integrated evaluation of the project, including survey data from practitioners, assessment of website use, a cross-sectional social network analysis, and process data. The findings highlight both the demand for professional development in this area, as well as the challenge of engaging sufficiently with practitioners in high-demand/low-resource settings to create changes in practice. We also present the next steps with this work, as we are refining the capacity-building program at this time, with the intention to offer trainings, technical assistance, and technology-enabled engagement in the next iteration
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Network-based social capital and capacity-building programs: an example from Ethiopia
Introduction
Capacity-building programs are vital for healthcare workforce development in low- and middle-income countries. In addition to increasing human capital, participation in such programs may lead to new professional networks and access to social capital. Although network development and social capital generation were not explicit program goals, we took advantage of a natural experiment and studied the social networks that developed in the first year of an executive-education Master of Hospital and Healthcare Administration (MHA) program in Jimma, Ethiopia.
Case description
We conducted a sociometric network analysis, which included all program participants and supporters (formally affiliated educators and mentors). We studied two networks: the Trainee Network (all 25 trainees) and the Trainee-Supporter Network (25 trainees and 38 supporters). The independent variable of interest was out-degree, the number of program-related connections reported by each respondent. We assessed social capital exchange in terms of resource exchange, both informational and functional. Contingency table analysis for relational data was used to evaluate the relationship between out-degree and informational and functional exchange.
Discussion and evaluation
Both networks demonstrated growth and inclusion of most or all network members. In the Trainee Network, those with the highest level of out-degree had the highest reports of informational exchange, χ2 (1, N = 23) = 123.61, p 0.05. In the Trainee-Supporter Network, trainees with the highest level of out-degree had the highest reports of informational exchange, χ2 (1, N = 23) = 74.93, p < 0.05. The same pattern held for functional exchange, χ2 (1, N = 23) = 81.31, p < 0.01.
Conclusions
We found substantial and productive development of social networks in the first year of a healthcare management capacity-building program. Environmental constraints, such as limited access to information and communication technologies, or challenges with transportation and logistics, may limit the ability of some participants to engage in the networks fully. This work suggests that intentional social network development may be an important opportunity for capacity-building programs as healthcare systems improve their ability to manage resources and tackle emerging problems
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Informal Training in Staff Networks to Support Dissemination of Health Promotion Programs
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Prevalence and Framing of Health Disparities in Local Print News: Implications for Multilevel Interventions to Address Cancer Inequalities
Background: Americans remain under-informed about cancer and other health disparities and the social determinants of health (SDH). The news media may be contributing to this knowledge deficit, whether by discussing these issues narrowly or ignoring them altogether. Because local media are particularly important in influencing public opinion and support for public policies, this study examines the prevalence and framing of disparities/SDH in local mainstream and ethnic print news.
Methods: We conducted a multi-method content analysis of local mainstream (English language) and ethnic (Spanish language) print news in two lower income cities in New England with substantial racial/ethnic minority populations. After establishing intercoder reliability (κ = 0.63–0.88), coders reviewed the primary English and Spanish language newspaper in each city, identifying both disparities and non-disparities health stories published between February 2010 and January 2011.
Results: Local print news coverage of cancer and other health disparities was rare. Of 650 health stories published across four newspapers during the one-year study period, only 21 (3.2%) discussed disparities/SDH. Although some stories identified causes of and solutions for disparities, these were often framed in individual (e.g., poor dietary habits) rather than social contextual terms (e.g., lack of food availability/affordability). Cancer and other health stories routinely missed opportunities to discuss disparities/SDH.
Conclusion: Local mainstream and ethnic media may be ideal targets for multilevel interventions designed to address cancer and other health inequalities.
Impact: By increasing media attention to and framing of health disparities, we may observe important downstream effects on public opinion and support for structural solutions to disparities, particularly at the local level
Collaboration networks of the implementation science centers for cancer control: A social network analysis
BACKGROUND: Multi-center research initiatives offer opportunities to develop and strengthen connections among researchers. These initiatives often have goals of increased scientific collaboration which can be examined using social network analysis.
METHODS: The National Cancer Institute (NCI)-funded Implementation Science Centers in Cancer Control (ISC
RESULTS: Of the 192 invitees, 182 network members completed the survey (95%). The most prevalent roles were faculty (60%) and research staff (24%). Almost one-quarter (23%) of members reported advanced expertise in IS, 42% intermediate, and 35% beginner. Most members were female (69%) and white (79%). One-third (33%) of collaboration ties were among members from different centers. Across all collaboration activities, the network had a density of 14%, suggesting moderate cohesion. Degree centralization (0.33) and betweenness centralization (0.07) measures suggest a fairly dispersed network (no single or few central member(s) holding all connections). The most prevalent and densely connected collaboration was in planning/conducting research (1470 ties; 8% density). Practice/policy dissemination had the fewest collaboration, lowest density (284 ties\u27 3% density), and the largest number of non-connected members (n=43). Access to the ISC
CONCLUSIONS: Results establish a baseline for assessing the growth of cross-center collaborations, highlighting specific areas in need of particular growth in network collaborations such as increasing engagement of racial and ethnic minorities and trainees or those with less expertise in IS
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Research in action: using positive deviance to improve quality of health care
Background
Despite decades of efforts to improve quality of health care, poor performance persists in many aspects of care. Less than 1% of the enormous national investment in medical research is focused on improving health care delivery. Furthermore, when effective innovations in clinical care are discovered, uptake of these innovations is often delayed and incomplete. In this paper, we build on the established principle of 'positive deviance' to propose an approach to identifying practices that improve health care quality.
Methods
We synthesize existing literature on positive deviance, describe major alternative approaches, propose benefits and limitations of a positive deviance approach for research directed toward improving quality of health care, and describe an application of this approach in improving hospital care for patients with acute myocardial infarction.
Results
The positive deviance approach, as adapted for use in health care, presumes that the knowledge about 'what works' is available in existing organizations that demonstrate consistently exceptional performance. Steps in this approach: identify 'positive deviants,' i.e., organizations that consistently demonstrate exceptionally high performance in the area of interest (e.g., proper medication use, timeliness of care); study the organizations in-depth using qualitative methods to generate hypotheses about practices that allow organizations to achieve top performance; test hypotheses statistically in larger, representative samples of organizations; and work in partnership with key stakeholders, including potential adopters, to disseminate the evidence about newly characterized best practices. The approach is particularly appropriate in situations where organizations can be ranked reliably based on valid performance measures, where there is substantial natural variation in performance within an industry, when openness about practices to achieve exceptional performance exists, and where there is an engaged constituency to promote uptake of discovered practices.
Conclusion
The identification and examination of health care organizations that demonstrate positive deviance provides an opportunity to characterize and disseminate strategies for improving quality
Addressing Cancer Disparities via Community Network Mobilization and Intersectoral Partnerships: A Social Network Analysis
Community mobilization and collaboration among diverse partners are vital components of the effort to reduce and eliminate cancer disparities in the United States. We studied the development and impact of intersectoral connections among the members of the Massachusetts Community Network for Cancer Education, Research, and Training (MassCONECT). As one of the Community Network Program sites funded by the National Cancer Institute, this infrastructure-building initiative utilized principles of Community-based Participatory Research (CBPR) to unite community coalitions, researchers, policymakers, and other important stakeholders to address cancer disparities in three Massachusetts communities: Boston, Lawrence, and Worcester. We conducted a cross-sectional, sociometric network analysis four years after the network was formed. A total of 38 of 55 members participated in the study (69% response rate). Over four years of collaboration, the number of intersectoral connections reported by members (intersectoral out-degree) increased, as did the extent to which such connections were reported reciprocally (intersectoral reciprocity). We assessed relationships between these markers of intersectoral collaboration and three intermediate outcomes in the effort to reduce and eliminate cancer disparities: delivery of community activities, policy engagement, and grants/publications. We found a positive and statistically significant relationship between intersectoral out-degree and community activities and policy engagement (the relationship was borderline significant for grants/publications). We found a positive and statistically significant relationship between intersectoral reciprocity and community activities and grants/publications (the relationship was borderline significant for policy engagement). The study suggests that intersectoral connections may be important drivers of diverse intermediate outcomes in the effort to reduce and eliminate cancer disparities. The findings support investment in infrastructure-building and intersectoral mobilization in addressing disparities and highlight the benefits of using CBPR approaches for such work
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