Enviromentally benign synthesis and application of some spinel ferrite nanopartilces

In this thesis, the commercial viability of the aminolytic synthesis method is explored through robustness, versatility, and waste reduction studies. We report the preparation of metal precursors and the development of a synthetic approach using an aminolytic reaction of metal carboxylates in oleylamine and non-coordinating solvent. Manganese doping in the cobalt ferrites allows for the investigation of the couplings. All the compositions in the series Co1-xMnxFe2O4, 0.0 x 1.0 were synthesized via the aminolytic reaction. The coercivity decreases with increasing Mn2+ concentration due to reducing of high magnetic anisotropy ion (Co2+) content. To our knowledge, this work is the first completed series of Co1-xMnxFe2O4. The method is used to synthesize manganese ferrites dope with chromium. This allows for the investigation of the effects of orbital momentum quantum coupling. All the compositions of MnFe2-xCrxO4, x= 0.0, 0.05, 0.13, 0.25, 0.43, 0.62, and 0.85, were synthesized via the In-situ aminolytic method. Chromium concentration weakens the couplings resulting in the decrease in overall magnetic moment. All by-products can be recycled for re-utilization. The "mother" solution can be used for multiple batches without treatment. Our trials have shown that the reaction could undergo ten reactions using the same solution without scarifying the quality or yield of the product. Finally, an environmental application is explored through the use of iron oxides. Samples of goethite, maghemite, magnetite, and hematite were synthesized and characterized. These nanoparticles were exposed to arsenic and chromium solutions to measure the percent uptake of contaminant by each phase. Adsorption isotherms were plotted to obtain Freundlich parameters. The adsorption constant (K) averages over a 400% increase on literature values. We synthesized hematite and maghemite core-shell particles and exposed them to arsenite and maghemite core-shell particles have the higher removal affinity due to their smaller size.PhDCommittee Chair: Zhang, Z. John; Committee Member: El-Sayed, Mostafa; Committee Member: Janata, Jiri; Committee Member: Jones, Chris; Committee Member: Wilkinson, Angu

Effects of Historic Preservation Policy on Urban Neighborhood Stabilization

Since the 1960s, urban neighborhoods in the United States have been affected by historic designation and local historic preservation policy raising concerns about social inequity in housing and services, environmental resources, and economic challenges. Although there is consensus that the role of public policy in historic preservation decision-making is related to neighborhood stabilization, little is known about the extent of the impact. Using Ostrom\u27s social-ecological systems theory as a guide, the purpose of this single case study of a historical district in the U.S. Mid-Atlantic region was to investigate the impact of implementation of local historic preservation policies and programs related to social and economic change. Data were collected from 11 interviews with residents and government officials and publicly available documents provided by the local government agency. These data were inductively coded and then subjected to thematic analysis. Findings indicate that areas of deficiency in historic preservation policy in the urban neighborhood affect social-economic systems due to the complex and integrated way that the components often work asynchronously. Collaboration between multiple types and levels of entities can offset the negatives and bolster the more positive aspects of historic preservation. The study includes recommendations to local government policy makers and organizations that emphasize the importance of integrated planning and development and the revision of current policy to reflect constituent needs. Maximizing the efficiency and operation of historic preservation policy may engender positive social change by optimizing economic impacts and lessening social disparities and environmental concerns, which may improve citizens\u27 quality of life and affected areas\u27 fiscal health

A socio-cultural study investigating the influences on food and lifestyle choices, and the cultural transition, of British Bangladeshis living in Tower Hamlets East London

The prevalence of obesity and Type 2 diabetes is increasing world-wide being most evident in non-industrialised populations, and in deprived communities and minority ethnic groups, residing in the "affluent west". In the UK, the South Asian population, and in particular the Bangladeshi community, are up to six times more likely than the general population to have Type 2 diabetes. In Tower Hamlets East London, the prevalence is higher than both the London and England average; with over half of the cases being Bangladeshi. There is strong evidence that it is the interaction between an altered lifestyle, associated with economic development and urbanisation, which has triggered this massive increase in the prevalence of Type 2 diabetes. Genetic causes, and poor foetal and infant nutrition, are also seen as contributory factors. Central to this thesis was the preposition that obesity and Type 2 diabetes are largely preventable and amenable to a wide range of public health prevention strategies. Too often a reductionist medical approach has been taken with the focus on individual behavioural change and few links to the culture of food and eating, or to the broader social, political, or economic context in which people live. This trans-cultural study utilised qualitative approaches over three phases: paired interviews, in-depth semi-structured interviews and multiple pass dietary recall; drawing upon current social science and public health nutrition paradigms to investigate the contextual factors influencing food choices and physical activity, as perceived by the community itself and key informants, as well as the trend in eating patterns between two generations of British Bangladeshis. Multiple drivers were revealed to be influencing food and activity choices with the community being significantly affected by urbanisation, being immersed in an obesogenic environment, the degree of acculturation into the British society and changes to the patriarchal structure of their community. The policy framework at the time of this research reflected an epistemological dilemma of a social issue continuing to be addressed with a largely clinical solution and the perception of a Government which despite outward appearances to the contrary, remained committed to the personalisation of the health agenda. The most recent change to the Coalition Government has seen this paradigm continuing, jarring sharply with the lived realities of the community and the overwhelming evidence that the obesity and diabetes epidemics cannot be dealt with by promoting behavioural change and individualised treatment alone. The long lasting theory in Public Health that the social dimensions of health need to be addressed in conjunction with biological determinants has been confirmed with a complex web of interactions weaving together to influence the choices being made, highlighting the interconnectedness of diet and culture, and the relationship to a culture in transition. The vast array of factors have substantial implications for further development of food and public health policy for this community relating to the prevention diet related non-communicable diseases, as well as for professional practice

An exploration of the ability of tepoxalin to ameliorate the degradation of articular cartilage in a canine in vitro model

<p>Abstract</p> <p>Background</p> <p>To study the ability of tepoxalin, a dual inhibitor of cyclooxygenase (COX) and lipoxygenase (LOX) and its active metabolite to reduce the catabolic response of cartilage to cytokine stimulation in an <it>in vitro </it>model of canine osteoarthritis (OA).</p> <p>Grossly normal cartilage was collected post-mortem from seven dogs that had no evidence of joint disease. Cartilage explants were cultured in media containing the recombinant canine interleukin-1<it>β </it>(IL-1<it>β</it>) at 100 ng/ml and recombinant human oncostatin-M (OSM) at 50 ng/ml. The effects of tepoxalin and its metabolite were studied at three concentrations (1 × 10^-5, 1 × 10^-6and 1 × 10^-7M). Total glycosaminoglycan (GAG) and collagen (hydroxyproline) release from cartilage explants were used as outcome measures of proteoglycan and collagen depletion respectively. PGE₂and LTB₄assays were performed to study the effects of the drug on COX and LOX activity.</p> <p>Results</p> <p>Treatment with IL-1<it>β </it>and OSM significantly upregulated both collagen (p = 0.004) and proteoglycan (p = 0.001) release from the explants. Tepoxalin at 10^-5M and 10^-6M caused a decrease in collagen release from the explants (p = 0.047 and p = 0.075). Drug treatment showed no effect on GAG release. PGE₂concentration in culture media at day 7 was significantly increased by IL-1<it>β </it>and OSM and treatment with both tepoxalin and its metabolite showed a trend towards dose-dependent reduction of PGE₂production. LTB₄concentrations were too low to be quantified. Cytotoxicity assays suggested that neither tepoxalin nor its metabolite had a toxic effect on the cartilage chondrocytes at the concentrations and used in this study.</p> <p>Conclusion</p> <p>This study provides evidence that tepoxalin exerts inhibition of COX and can reduce <it>in vitro </it>collagen loss from canine cartilage explants at a concentration of 10^-5M. We can conclude that, in this model, tepoxalin can partially inhibit the development of cartilage degeneration when it is available locally to the tissue.</p

Public Engagement on Climate and Health in Museums and Participatory Dialogues may Foster Behavior Change

As scientific knowledge grows and the planet’s human population makes unprecedented changes, decision-making places more and more demands on the everyday democratic participant. Yet efforts to help the public acquire and make use of evidence-based information fall short. We present preliminary comparisons of three participatory design models of public engagement with science designed to encourage community action rather than just raise awareness in participants on local public health issues impacted by climate change. We collected survey data at two in-person community-based participatory dialogues and a museum exhibit and presented but received no surveys from televised versions of the participatory dialogues. Results indicated that behavior change was indeed salient to participants. Actions participants plan to take included sharing what they learned, contacting legislators, and direct conservation efforts. Future research should study whether participants undertake planned actions and do so in groups rather than as individuals

Panel-Based Exhibit Using Participatory Design Elements May Motivate Behavior Change

Meaningful science engagement beyond one-way outreach is needed to encourage science-based decision making. This pilot study aimed to instigate dialogue and deliberation concerning climate change and public health. Feedback from science café participants was used to design a panel-based museum exhibit that asked visitors to make action plans concerning such issues. Using intercept interviews and visitor comment card data, we found that visitors developed general or highly individualistic action plans to address these issues. Results suggest that employing participatory design methods when developing controversial socio-scientific exhibits can aid engagement. We conclude by recommending participatory strategies for implementing two-way science communication

Expectant fathers’ participation in antenatal care services in Papua New Guinea: a qualitative inquiry

Background: The importance of engaging men in maternal and child health programs is well recognised internationally. In Papua New Guinea (PNG), men’s involvement in maternal and child health services remains limited and barriers and enablers to involving fathers in antenatal care have not been well studied. The purpose of this paper is to explore attitudes to expectant fathers participating in antenatal care, and to identify barriers and enablers to men‘s participation in antenatal care with their pregnant partner in PNG. Methods: Twenty-eight focus group discussions were conducted with purposively selected pregnant women, expectant fathers, older men and older women across four provinces of PNG. Fourteen key informant interviews were also conducted with health workers. Qualitative data generated were analysed thematically. Results: While some men accompany their pregnant partners to the antenatal clinic and wait outside, very few men participate in antenatal consultations. Factors supporting fathers’ participation in antenatal consultations included feelings of shared responsibility for the unborn child, concern for the mother’s or baby’s health, the child being a first child, friendly health workers, and male health workers. Sociocultural norms and taboos were the most significant barrier to fathers’ participation in antenatal care, contributing to men feeling ashamed or embarrassed to attend clinic with their partner. Other barriers to men’s participation included fear of HIV or sexually transmitted infection testing, lack of separate waiting spaces for men, rude treatment by health workers, and being in a polygamous relationship. Building community awareness of the benefits of fathers participating in maternal and child health service, inviting fathers to attend antenatal care if their pregnant partner would like them to, and ensuring clinic spaces and staff are welcoming to men were strategies suggested for increasing fathers’ participation in antenatal care. Conclusion: This study identified significant sociocultural and health service barriers to expectant fathers’ participation in antenatal care in PNG. Our findings highlight the need to address these barriers – through health staff training and support, changes to health facility layout and community awareness raising – so that couples in PNG can access the benefits of men’s participation in antenatal care

Quantitative prediction of stone fragility from routine single and dual energy CT: proof of feasibility

Rationale and Objectives Previous studies have demonstrated a qualitative relationship between stone fragility and internal stone morphology. The goal of this study was to quantify morphological features from dual-energy CT images and assess their relationship to stone fragility. Materials and Methods Thirty-three calcified urinary stones were scanned with micro CT. Next, they were placed within torso-shaped water phantoms and scanned with the dual-energy CT stone composition protocol in routine use at our institution. Mixed low-and high-energy images were used to measure volume, surface roughness, and 12 metrics describing internal morphology for each stone. The ratios of low- to high-energy CT numbers were also measured. Subsequent to imaging, stone fragility was measured by disintegrating each stone in a controlled ex vivo experiment using an ultrasonic lithotripter and recording the time to comminution. A multivariable linear regression model was developed to predict time to comminution. Results The average stone volume was 300 mm3 (range 134–674 mm3). The average comminution time measured ex vivo was 32 s (range 7–115 s). Stone volume, dual-energy CT number ratio and surface roughness were found to have the best combined predictive ability to estimate comminution time (adjusted R2= 0.58). The predictive ability of mixed dual-energy CT images, without use of the dual-energy CT number ratio, to estimate comminution time was slightly inferior, with an adjusted R2 of 0.54. Conclusion Dual-energy CT number ratios, volume, and morphological metrics may provide a method for predicting stone fragility, as measured by time to comminution from ultrasonic lithotripsy

Classification of the Universe of Immune Epitope Literature: Representation and Knowledge Gaps

A significant fraction of the more than 18 million scientific articles currently indexed in the PubMed database are related to immune responses to various agents, including infectious microbes, autoantigens, allergens, transplants, cancer antigens and others. The Immune Epitope Database (IEDB) is an online repository that catalogs immune epitope reactivity data derived from articles listed in the National Library of Medicine PubMed database. The IEDB is maintained and continually updated by monitoring PubMed for new, potentially relevant references.Herein we detail the classification of all epitope-specific literature in over 100 different immunological domains representing Infectious Diseases and Microbes, Autoimmunity, Allergy, Transplantation and Cancer. The relative number of references in each category reflects past and present areas of research on immune reactivities. In addition to describing the overall landscape of data distribution, this particular characterization of the epitope reference data also allows for the exploration of possible correlations with global disease morbidity and mortality data.While in most cases diseases associated with high morbidity and mortality rates were amongst the most studied, a number of high impact diseases such as dengue, Schistosoma, HSV-2, B. pertussis and Chlamydia trachoma, were found to have very little coverage. The data analyzed in this fashion represents the first estimate of how reported immunological data corresponds to disease-related morbidity and mortality, and confirms significant discrepancies in the overall research foci versus disease burden, thus identifying important gaps to be pursued by future research. These findings may also provide a justification for redirecting a portion of research funds into some of the underfunded, critical disease areas

Behind the Mask: can HARMONI@ELT detect biosignatures in the reflected light of Proxima b?

Proxima b is a rocky exoplanet in the habitable zone of the nearest star system and a key test case in the search for extraterrestrial life. Here, we investigate the characterization of a potential Earth-like atmosphere around Proxima b in reflected light via molecule mapping, combining high resolution spectroscopy (HRS) and high contrast imaging, using the first-generation integral field spectrograph HARMONI on the $39$-m Extremely Large Telescope. We simulate comprehensive observations of Proxima b at an assumed $45^{\circ}$ inclination using HARMONI's High Contrast Adaptive Optics mode, with spatial resolution $\sim 8$mas ($3.88$mas/spaxel) and spectral resolving power $R\simeq17,000$ between $1.538$--$1.678 \mu m$, containing the spectral features of water, carbon dioxide and methane. Tellurics, stellar features, and additional noise sources are included, and removed using established molecule mapping techniques. We find that HARMONI's current focal plane mask (FPM) is too large and obscures the orbit of Proxima b and thus explore smaller and offset FPMs to yield a detection. A $\rm{S/N}=5$ detection of Proxima b's reflected light, suitable for atmospheric characterisation, is possible with such modifications, requiring a minimum of $20$ hours, but ideally at least $30$ hours of integration time. We highlight that such detections do not scale with the photon noise, hence suitably detailed simulations of future instruments for the ELTs are needed to fully understand their ability to perform HRS observations of exoplanet atmospheres. Alterations to the HARMONI FPM design are feasible at this stage, but must be considered in context of other science cases.Comment: 14 pages, 9 figures, accepted to MNRA