94 research outputs found
Program Improvement and Practice: In-Service and Pre-Service Student Teaching Reflections
A qualitative study was conducted with graduates (in-service teachers) and pre-service teacher candidates from a traditional elementary education program to explore perceptions of the student teaching process and its impact on teaching philosophy and practices. The program graduates and pre-service teachers described their experience as valuable, but believed their knowledge of pedagogy and classroom management to be deficient. The value of the internship process and implications for program improvement are discussed. Theory without practice is dead, and practice without theory is blind. — Ano
Mothers of children with congenital heart defects: the effects of ethnicity and education on perceptions, attitudes and feelings; (Implications for social work practice)
Thesis (M.S.)--Boston University, 196
The iron mediated (1,5)-homologous Michael reaction as a route to spirocyclic ring systems.
The reaction between -acetoxy--unsaturated esters with diiron nonacarbonyl produces the \eta\sp2-iron tetracarbonyl complexes. Addition of a Lewis acid, such as boron trifluoride etherate, produces \eta\sp3-iron allyl cationic complexes. These complexes react with silyl enol ethers and silyl ketene acetals to afford the addition products. The regiochemistry is such that the addition occurs at the terminus of the allyl fragment remote from the ester function to produce substitution products. The geometric stability of the iron allyl cation allows the stereochemical integrity of the double bond to remain intact during the course of the reaction. Cyclic silyl ketene acetals and silyl enol ethers provide difunctionalized cyclic products containing a quaternary centre. These products are precursors to a variety of spirocyclic ring systems. Three types of spirocyclizations were performed with the iron allyl addition products. Attempts at cyclizing the alkene failed to produce any product cleanly, so the compounds were first hydrogenated. The Dieckmann and the acyloin condensations produced the corresponding spirocycles. Cyclization by metal halogen exchange also formed a spirocycle in low yield. Further investigation of this reaction and its application to natural product synthesis will be discussed. Source: Masters Abstracts International, Volume: 34-06, page: 2378. Adviser: James R. Green. Thesis (M.Sc.)--University of Windsor (Canada), 1996
Macromolecular crowding modulates folding mechanism of alpha/beta protein apoflavodoxin
Protein dynamics in cells may be different from that in dilute solutions in
vitro since the environment in cells is highly concentrated with other
macromolecules. This volume exclusion due to macromolecular crowding is
predicted to affect both equilibrium and kinetic processes involving protein
conformational changes. To quantify macromolecular crowding effects on protein
folding mechanisms, here we have investigated the folding energy landscape of
an alpha/beta protein, apoflavodoxin, in the presence of inert macromolecular
crowding agents using in silico and in vitro approaches. By coarse-grained
molecular simulations and topology-based potential interactions, we probed the
effects of increased volume fraction of crowding agents (phi_c) as well as of
crowding agent geometry (sphere or spherocylinder) at high phi_c. Parallel
kinetic folding experiments with purified Desulfovibro desulfuricans
apoflavodoxin in vitro were performed in the presence of Ficoll (sphere) and
Dextran (spherocylinder) synthetic crowding agents. In conclusion, we have
identified in silico crowding conditions that best enhance protein stability
and discovered that upon manipulation of the crowding conditions, folding
routes experiencing topological frustrations can be either enhanced or
relieved. The test-tube experiments confirmed that apoflavodoxin's
time-resolved folding path is modulated by crowding agent geometry. We propose
that macromolecular crowding effects may be a tool for manipulation of protein
folding and function in living cells.Comment: to appear in Biophysical Journal (2009). to appear in Biophysical
Journal (2009
Salt Reduction Initiatives around the World – A Systematic Review of Progress towards the Global Target
Objective
To quantify progress with the initiation of salt reduction strategies around the world in the context of the global target to reduce population salt intake by 30% by 2025.
Methods
A systematic review of the published and grey literature was supplemented by questionnaires sent to country program leaders. Core characteristics of strategies were extracted and categorised according to a pre-defined framework.
Results
A total of 75 countries now have a national salt reduction strategy, more than double the number reported in a similar review done in 2010. The majority of programs are multifaceted and include industry engagement to reformulate products (n = 61), establishment of sodium content targets for foods (39), consumer education (71), front-of-pack labelling schemes (31), taxation on high-salt foods (3) and interventions in public institutions (54). Legislative action related to salt reduction such as mandatory targets, front of pack labelling, food procurement policies and taxation have been implemented in 33 countries. 12 countries have reported reductions in population salt intake, 19 reduced salt content in foods and 6 improvements in consumer knowledge, attitudes or behaviours relating to salt.
Conclusion
The large and increasing number of countries with salt reduction strategies in place is encouraging although activity remains limited in low- and middle-income regions. The absence of a consistent approach to implementation highlights uncertainty about the elements most important to success. Rigorous evaluation of ongoing programs and initiation of salt reduction programs, particularly in low- and middle- income countries, will be vital to achieving the targeted 30% reduction in salt intake
How could differences in 'control over destiny' lead to socio-economic inequalities in health? : A synthesis of theories and pathways in the living environment
We conducted the first synthesis of theories on causal associations and pathways connecting degree of control in the living environment to socio-economic inequalities in health-related outcomes. We identified the main theories about how differences in 'control over destiny' could lead to socio-economic inequalities in health, and conceptualised these at three distinct explanatory levels: micro/personal; meso/community; and macro/societal. These levels are interrelated but have rarely been considered together in the disparate literatures in which they are located. This synthesis of theories provides new conceptual frameworks to contribute to the design and conduct of theory-led evaluations of actions to tackle inequalities in health
Rheumatoid arthritis - clinical aspects: 134. Predictors of Joint Damage in South Africans with Rheumatoid Arthritis
Background: Rheumatoid arthritis (RA) causes progressive joint damage and functional disability. Studies on factors affecting joint damage as clinical outcome are lacking in Africa. The aim of the present study was to identify predictors of joint damage in adult South Africans with established RA. Methods: A cross-sectional study of 100 black patients with RA of >5 years were assessed for joint damage using a validated clinical method, the RA articular damage (RAAD) score. Potential predictors of joint damage that were documented included socio-demographics, smoking, body mass index (BMI), disease duration, delay in disease modifying antirheumatic drug (DMARD) initiation, global disease activity as measured by the disease activity score (DAS28), erythrocyte sedimentation rate (ESR), C reactive protein (CRP), and autoantibody status. The predictive value of variables was assessed by univariate and stepwise multivariate regression analyses. A p value <0.05 was considered significant. Results: The mean (SD) age was 56 (9.8) years, disease duration 17.5 (8.5) years, educational level 7.5 (3.5) years and DMARD lag was 9 (8.8) years. Female to male ratio was 10:1. The mean (SD) DAS28 was 4.9 (1.5) and total RAAD score was 28.3 (12.8). The mean (SD) BMI was 27.2 kg/m2 (6.2) and 93% of patients were rheumatoid factor (RF) positive. More than 90% of patients received between 2 to 3 DMARDs. Significant univariate predictors of a poor RAAD score were increasing age (p = 0.001), lower education level (p = 0.019), longer disease duration (p < 0.001), longer DMARD lag (p = 0.014), lower BMI (p = 0.025), high RF titre (p < 0.001) and high ESR (p = 0.008). The multivariate regression analysis showed that the only independent significant predictors of a higher mean RAAD score were older age at disease onset (p = 0.04), disease duration (p < 0.001) and RF titre (p < 0.001). There was also a negative association between BMI and the mean total RAAD score (p = 0.049). Conclusions: Patients with longstanding established RA have more severe irreversible joint damage as measured by the clinical RAAD score, contrary to other studies in Africa. This is largely reflected by a delay in the initiation of early effective treatment. Independent of disease duration, older age at disease onset and a higher RF titre are strongly associated with more joint damage. The inverse association between BMI and articular damage in RA has been observed in several studies using radiographic damage scores. The mechanisms underlying this paradoxical association are still widely unknown but adipokines have recently been suggested to play a role. Disclosure statement: C.I. has received a research grant from the Connective Tissue Diseases Research Fund, University of the Witwatersrand. All other authors have declared no conflicts of interes
Safety, immunogenicity, and reactogenicity of BNT162b2 and mRNA-1273 COVID-19 vaccines given as fourth-dose boosters following two doses of ChAdOx1 nCoV-19 or BNT162b2 and a third dose of BNT162b2 (COV-BOOST): a multicentre, blinded, phase 2, randomised trial
BHPR research: qualitative1. Complex reasoning determines patients' perception of outcome following foot surgery in rheumatoid arhtritis
Background: Foot surgery is common in patients with RA but research into surgical outcomes is limited and conceptually flawed as current outcome measures lack face validity: to date no one has asked patients what is important to them. This study aimed to determine which factors are important to patients when evaluating the success of foot surgery in RA Methods: Semi structured interviews of RA patients who had undergone foot surgery were conducted and transcribed verbatim. Thematic analysis of interviews was conducted to explore issues that were important to patients. Results: 11 RA patients (9 ♂, mean age 59, dis dur = 22yrs, mean of 3 yrs post op) with mixed experiences of foot surgery were interviewed. Patients interpreted outcome in respect to a multitude of factors, frequently positive change in one aspect contrasted with negative opinions about another. Overall, four major themes emerged. Function: Functional ability & participation in valued activities were very important to patients. Walking ability was a key concern but patients interpreted levels of activity in light of other aspects of their disease, reflecting on change in functional ability more than overall level. Positive feelings of improved mobility were often moderated by negative self perception ("I mean, I still walk like a waddling duck”). Appearance: Appearance was important to almost all patients but perhaps the most complex theme of all. Physical appearance, foot shape, and footwear were closely interlinked, yet patients saw these as distinct separate concepts. Patients need to legitimize these feelings was clear and they frequently entered into a defensive repertoire ("it's not cosmetic surgery; it's something that's more important than that, you know?”). Clinician opinion: Surgeons' post operative evaluation of the procedure was very influential. The impact of this appraisal continued to affect patients' lasting impression irrespective of how the outcome compared to their initial goals ("when he'd done it ... he said that hasn't worked as good as he'd wanted to ... but the pain has gone”). Pain: Whilst pain was important to almost all patients, it appeared to be less important than the other themes. Pain was predominately raised when it influenced other themes, such as function; many still felt the need to legitimize their foot pain in order for health professionals to take it seriously ("in the end I went to my GP because it had happened a few times and I went to an orthopaedic surgeon who was quite dismissive of it, it was like what are you complaining about”). Conclusions: Patients interpret the outcome of foot surgery using a multitude of interrelated factors, particularly functional ability, appearance and surgeons' appraisal of the procedure. While pain was often noted, this appeared less important than other factors in the overall outcome of the surgery. Future research into foot surgery should incorporate the complexity of how patients determine their outcome Disclosure statement: All authors have declared no conflicts of interes
Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector
A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements
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