Characterization, Immobilization, and Polymer Related Applications of Watermelon Seed Powder, a Practical Source of Urease Enzyme

Urease enzyme was crystallized almost a century ago, and to this day its intrinsic stability is not ideal for everyday applications. This work introduces a new process by which a naturally encapsulated material, watermelon seed powder (WMSP), is characterized for its stability and activity. WMSP enzymatic activity has been measured for over a year at various storage conditions—exposed to ambient atmosphere for a year, WMSP retained above 90% activity. In aqueous conditions, the enzyme maintained above 60% activity after two months; with the addition of a preservative that number stays at about 90%. There is a pH shift of the maximum activity at 8.1 pH in addition to a broadening of the activity curve allowing for a wider range of reactions. In Chapter 3, immobilization techniques were employed on these powders, enhancing their usability and in turn presented some interesting dynamics. One of the techniques physically encapsulated the WMSP inside a porous resin, essentially creating a urea-ammonia exchange resin. These particles were subject to 10 cycles of urea hydrolysis, without any change in the urea-urease clock reaction. The agar immobilized WMSPs exhibited a behavior called quorum sensing. That is a biological communication process by which bacteria express certain genes when a “quorum” or sufficient number are in proximity of each other. With certain parameters, the particles will not clock individually, but when in a cluster of particles, the autocatalysis occurs. This property was then coupled with a hydrogel polymerization that gels in basic conditions. The WMSP particles in principle are biofilm generating analogues. Lastly, Chapter 4 presents an application of WMSP as a base generator for several adhesive formulations and outlines some potential future uses of WMSP

Insights into Student Cognition: Creative Exercises as an Evaluation Tool in Undergraduate First-year Organic Chemistry

It is known that while students can be adept at recalling specific information, especially in end of semester summative exams, they can still often struggle to connect or link this information over different topic areas. In many cases, this issue is exacerbated by traditional assessments and teaching styles that focus on and reward students who have only interacted with the learning materials on a more surface level. Many attempts have been made over time to rectify this, with one such example shown in the use of Creative Exercises (CEs). CEs are open-ended tasks that allow students to connect as much prior knowledge as possible into one cohesive response, potentially developing a student’s ability to link and connect disparate topic areas and content. In this study, CEs were introduced into a large scale first-year course and focused on fundamental organic chemistry reactions for the first time (to the best of our knowledge). Students performed the CEs in groups, and the paper responses were collected over six weeks (N=945 in total). Analysis of these artefacts revealed that students did indeed struggle to connect information over subsequent teaching weeks. This inability to connect information was despite being encouraged to do so both by the tasks and the teaching staff. Additionally, while more ‘advanced’ students (as noted by prior performance) were noted to raise more topics in a given week, they were just as susceptible to ‘siloing’ the information as lower-performing students. Recommendations are made on the future use of CEs

An agenda for the study of Public Administration in Developing Countries

Developing nations demand a different scholarly approach in the field of public administration. We advance an agenda for research that stands on four pillars. First, in the absence of easily accessible data scholars of developing world public administration must assemble it for themselves. Second, building and testing theory plays a paramount role because researchers face limited information. Third, in developing countries, multi‐national and non‐governmental organizations are often crucial and must be considered in studying public administration. Fourth, given the novelties and ambiguities researchers face, qualitative information must be integrated throughout the research process. Our article—and the articles in this volume—constitute a call for developing country research to contribute to the study of public administration writ large, informing our understanding of both developing and developed states.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162699/2/gove12520_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162699/1/gove12520.pd

Community-based physical activity and nutrition programme for adults with metabolic syndrome in Vietnam: Study protocol for a cluster-randomised controlled trial

Introduction Metabolic syndrome (MetS) is a cluster of risk factors for cardiovascular diseases and type II diabetes. In Vietnam, more than one-quarter of its population aged 50-65 have MetS. This cluster-randomised controlled trial aims to evaluate the effectiveness of interventions to increase levels of physical activity and improve dietary behaviours among Vietnamese adults aged 50-65years with MetS. Method and analysis This 6-month community-based intervention includes a range of strategies to improve physical activity and nutrition for adults with MetS in Hanam, a province located in northern Vietnam. 600 participants will be recruited from 6 communes with 100 participants per commune. The 6 selected communes will be randomly allocated to either an intervention group (m=3; n=300) or a control group (m=3; n=300). The intervention comprises booklets, education sessions, resistance bands and attending local walking groups that provide information and encourage participants to improve their physical activity and healthy eating behaviours during the 6-month period. The control group participants will receive standard and 1-time advice. Social cognitive theory is the theoretical concept underpinning this study. Measurements will be taken at baseline and postintervention to evaluate programme effectiveness. Ethics and dissemination The research protocol was approved by the Curtin University Human Research Ethics Committee (approval number: HR139/2014). The results of the study will be disseminated through publications, reports and conference presentations

Effects of rate, temperature and absorption of organic solvents on the fracture of plain and glass-filled polystyrene

The rate/temperature dependent fracture behaviour of plain and glass-filled polystyrene has been investigated over the crack speed ( a ) range of 10 −6 to 10 −2 m sec −1 and in the temperature ( T ) range of 296 to 363 K. The K c (a, T) relationships obtained, where K c is the stress intensity factor at fracture, are shown to follow those given by the Williams/Marshall relaxation crack growth model and the toughness-biased rate theory. Crack propagation in both materials is shown to be controlled by a β -relaxation molecular process associated with crazing. Crack instabilities observed in plain polystyrene are analysed successfully in terms of isothermal-adiabatic transitions at the crack tip. Fracture initiation experiments are also conducted in which the effects of organic liquids on the fracture resistances of both plain/glass-filled polystyrene have been determined. Good correlations between K i 2 ( K i being the crack initiation stress intensity factor) and δ s , solvent solubility parameter, of various liquid environments have been obtained, which give a minimum K i 2 value at δ s ≈ δ p , where δ p is the solubility parameter of the polymer. For a given temperature, liquid environment and crack speed, the glass-filled polystyrene is shown to possess greater resistances to crack propagation than plain polystyrene.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44672/1/10853_2005_Article_BF01209454.pd

A Novel Analytical Framework for Dissecting the Genetic Architecture of Behavioral Symptoms in Neuropsychiatric Disorders

Background: For diagnosis of neuropsychiatric disorders, a categorical classification system is often utilized as a simple way for conceptualizing an often complex clinical picture. This approach provides an unsatisfactory model of mental illness, since in practice patients do not conform to these prototypical diagnostic categories. Family studies show notable familial co-aggregation between schizophrenia and bipolar illness and between schizoaffective disorders and both bipolar disorder and schizophrenia, revealing that mental illness does not conform to such categorical models and is likely to follow a continuum encompassing a spectrum of behavioral symptoms. Results and Methodology: We introduce an analytic framework to dissect the phenotypic heterogeneity present in complex psychiatric disorders based on the conceptual paradigm of a continuum of psychosis. The approach identifies subgroups of behavioral symptoms that are likely to be phenotypically and genetically homogenous. We have evaluated this approach through analysis of simulated data with simulated behavioral traits and predisposing genetic factors. We also apply this approach to a psychiatric dataset of a genome scan for schizophrenia for which extensive behavioral information was collected for each individual patient and their families. With this approach, we identified significant evidence for linkage among depressed individuals with two distinct symptom profiles, that is individuals with sleep disturbance symptoms with linkage on chromosome 2q13 and also a mutually exclusive group of individuals with symptoms of concentration problems with linkage on chromosome 2q35. In addition we identified a subset of individuals with schizophrenia defined by language disturbances with linkage to chromosome 2p25.1 and a group of patients with a phenotype intermediate between those of schizophrenia and schizoaffective disorder with linkage to chromosome 2p21. Conclusions: The findings presented are novel and demonstrate the efficacy of this approach in detection of genes underlying such complex human disorders as schizophrenia and depression

Social Media Use by Residents and Faculty in Otolaryngology Training Programs.

OBJECTIVES: Despite the growth of social media in healthcare, the appropriateness of online friendships between otolaryngological residents and attendings is poorly defined in the current literature. This issue is of growing importance, particularly as residency programs increasingly utilize social media as a means of connecting with and evaluating applicants due to limited in-person experiences during the COVID-19 pandemic. Our objective was to better understand the prevalence of and concerns surrounding social media use between residents and faculty. METHODS: This study sent out 2 surveys in 2017 to all United States Otolaryngology residency program directors to disperse to their residents and attendings, respectively. RESULTS: We received a response from 72 residents and 98 attendings. Our findings show that social media is commonly used by both residents and attendings, and most residents have at least 1 online friendship with an attending. Resident and attending opinions diverge on topics such as appropriateness of use, privacy settings, and professionalism. CONCLUSIONS: We call on residency programs to delineate a transparent social media policy so applicant expectations on social media are clear

On the stability of cracking in tapered DCB testpieces

The conventional tapered DCB specimen loaded at the apex is shown to exhibit less stability than parallel DCB testpieces cracking under stiff testing conditions. A modified test with loadings applied at the thick base instead of near the apex is suggested. Experiments agree with theory that this provides better cracking stability and easier control of the crack path, along with a wider range of crack velocities in one test. On montre que les éprouvettes doubles Cantilever conventionelles à bords convergents et chargées à leur extrémité présentent une stabilité moindre que les éprouvettes à bords parallèles, lors de la fissuration sous des conditions d'essai rigides. On suggère un essai modifié, où les charges sont appliquées du côté le plus épais au lieu du voisinage de la pointe de l'éprouvette.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42754/1/10704_2004_Article_BF00033840.pd

Determination of valid R -curves for materials with large fracture toughness to yield strength ratios

Crack growth resistance curves are derived from a generalised theory of quasi-static crack propagation due to Gurney and Hunt. Both the subcritical and continuous cracking regions are investigated, where the fracture toughness of the material may depend on the cracking rate, the reacting environment at the crack tip and the mode of fracture. Precise conditions for stability of the spreading crack relative to chosen constraints of either a displacement- or load-controlled machine are formulated. Cracking of sheet materials with high fracture toughness and low yield stress, (e.g. ( K /σ y ) 2 > 200 mm), which do not satisfy certain size requirements, is often complicated by generalised yielding at regions remote from the crack tip. Complete R -curves for such materials cannot be established with conventional testpieces in the laboratory. The present paper adopts a new experimental technique [1] where a laboratory size reinforcement rig attached to the testpiece eliminates all irreversibilities caused by generalised yielding. Valid fracture toughness values and crack growth resistance curves are thereby determined, irrespective of the amount of elastic and plastic deformations occurring at the crack tip. Successful R -curve experiments are described for fracture in a few ductile and tough materials such as 7075-T3. and 1100-0 aluminium alloys, and a low carbon steel. Comparison is made with other published R -curves, and the influence of sheet thickness and ( K 1 c /σ y ) ratio on the geometry of R -curves is investigated. A simple relationship for R -curves is suggested, viz. : R = R 0 + (Δ L ) p , where, it seems, R 0 can be identified with the plane strain toughness (i.e. R 0 = G 1c = K 1c 2 / E (1 - v 2 )1/2). A possible reason for this unexpected result is given in the paper. Useful estimates of K lc may thus be available from thin sheet tests.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42760/1/10704_2004_Article_BF00032834.pd

Promoting evidence-based policies, programs and services for ageing and health in Fiji

Population ageing presents significant implications for economies, health systems and social protection globally. In Pacific Island countries, the once young populations are ageing rapidly, yet national health systems remain vastly unprepared to cope with the complex needs of a growing number of older persons. The ability of Pacific governments to ‘re-orient health systems to respond to the needs of older people’ (WHO, 2014), is hindered by a lack of knowledge of what’s needed and what works for the care of older persons in their context. Limited translatable epidemiological data to underpin predictions of demographic and disease trends, lack of knowledge and coordination of multi-sectoral policies and services for the older population, and poor understanding of the preferences of older persons themselves, present significant barriers to driving evidence-based health policies and programs to enhance healthy ageing. This report presents the findings of a 2019/2020 scoping study of policy, program and service priorities to guide an effective health system response to population ageing in one of the most rapidly ageing Pacific Island countries, Fiji