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Dementia, a term that describes a variety of brain conditions marked by gradual, persistent and progressive cognitive decline, affects a significant proportion of older adults. Older adults with dementia are sometimes perceived less favourably than those without dementia. Furthermore, compared to persons without dementia, those with dementia are often perceived by others as having reduced personhood. This study was aimed at investigating whether differences in attitudes towards dementia and personhood perceptions vary as a function of age group, care-giver status, attitudes towards ageing, dementia knowledge, gender and education. In total 196 younger, middle-aged and older adults were recruited. Findings revealed that being a care-giver as well as having less ageist attitudes were predictive of being more comfortable around persons with dementia, having more knowledge about dementia and ascribing greater personhood to people with dementia. Those with more dementia knowledge (prior to the study) were less comfortable around people with dementia. Finally, when controlling this prior dementia knowledge, older adults were more comfortable around people with dementia compared to younger and middle-aged adults. Gender and education were not associated with any of the variables under study. Findings contribute to a better understanding of the role of age- and care-giver-related factors in the determination of attitudes towards dementia.
OBJECTIVES/SPECIFIC AIMS: The aim of this study is to compare intestinal phosphorus absorption in healthy adults and moderate stage chronic kidney disease patients in the context of a controlled feeding study METHODS/STUDY POPULATION: Participants are 30-75 years old and include 10 healthy subjects and 10 moderate-staged CKD patients. Each subject pool will be enrolled in a 9-day study period including 7 days of controlled feeding of a 1500 mg phosphorus diet. Following the controlled feeding, two days of absorption tests will take place (oral and IV tests) utilizing radioisotopic phosphorus to calculate fractional absorption efficiency. RESULTS/ANTICIPATED RESULTS: Current enrollment has produced 7 total matched subject (current n = 14/20). Four of the 7 pairs of completed subjects are female and 3 of 7 are black. Preliminary kinetic modeling data from the first enrolled subject show a moderate CKD patient with fractional absorption of 0.375. With forthcoming analyses, we expect that this fractional absorption result will not be statistically different from this subject’s matched pair, nor will each groups average absorption be different from the other. Additionally, we expect absorption to be maintained even with changes in secondary outcomes measures in serum (FGF23, 1,25-dihydroxyvitamin D, parathyroid hormone, and total phosphorus) in CKD patients. DISCUSSION/SIGNIFICANCE OF IMPACT: Lack of statistical difference in fractional phosphorus absorption between gropus would support that intestinal phosphorus absorption is inappropriately normal in CKD patients compared to healthy adults, despite evidence of abnormal phosphorus homeostatic mechanisms. Future studies will consider the effect of dietary P restriction, the most common nutrition intervention in moderate stage CKD, on fractional absorption efficiency in CKD.
If the joint clearances of the joints of a manipulator are considered, an unconstrained motion of the end-effector can be computed. This is true for all poses of the manipulator, even with all actuators locked.
This paper presents how this unconstrained motion can be determined for a planar 3-RPR manipulator. The singularities are then studied. It is shown that when clearances are considered, the singularity curves normally found in the workspace of such a manipulator become singular zones. These zones can be significant and greatly reduce the usable workspace of a manipulator. Since a prescribed configuration that would not, in theory, corresponds to a singular pose can become singular due to the unconstrained motion, the results of this paper are relevant to manipulator design and trajectory planning.
Introduction: Understanding factors that influence laboratory test ordering in emergency departments (EDs) can help to improve current laboratory test ordering practices. The aim of this study is to compare patterns and influences in laboratory test ordering between emergency physicians and nurses at two ED sites, Halifax Infirmary (HI) and Dartmouth General (DG). Methods: A mixed-methods approach involving administrative data and telephone interviews was employed. Data from 211,279 patients at HI and DG EDs were analyzed. Chi-square analysis and binary logistic regression were used to determine significant factors influencing whether a test was ordered, as well as significant factors predicting likelihood of a nurse or a physician ordering a test. All significant associations had a p-value of <0.0001. Interviews were conducted (n=25) with doctors and nurses in order to explore areas of potential influence in a clinician’s decision-making process, and discuss what makes decision making difficult or inconsistent in the ED. These interviews were analyzed according to the Theoretical Domains Framework. The interviews were coded by two individuals using a consensus methodology in order to ensure accuracy of coding. Results: Overall, laboratory tests were more likely to be ordered at DG than at HI (OR=1.52, 95% CI: [1.48, 1.55]). Laboratory tests were more likely to be ordered by nurses at DG than at HI (OR=1.58, 95% CI: [1.54, 1.62]). Laboratory tests were more likely to be ordered if the ED was not busy, if the patient was over 65, had a high acuity, had a long stay in the ED, required consults, or was admitted to hospital. Doctors were more likely to order a laboratory test in patients over 65, requiring consults or hospital admission, whereas nurses were more likely to order laboratory tests in patients with high acuity or long stays in the ED. Data from the interviews suggested differing influences on decision making between nurses and doctors, especially in the areas of social influence and knowledge. Conclusion: Currently, there is limited research that investigates behaviour of both emergency physicians and nurses. By determining barriers that are most amenable to behaviour change in emergency physicians and nurses, findings from this work may be used to update practice guidelines, ensuring more consistency and efficiency in laboratory test ordering in the ED.
“Bottom-up” assembly of fully functional cell-based materials has enormous potential for replicating endogenous tissues. Currently, most tissue-engineering strategies are based on incorporating dissociated cells into an artificial three-dimensional matrix of supportive structural elements that direct cellular migration, proliferation, and organization. The matrix provides “top-down” guidance cues that impose assembly directions on the cells; however, the matrix also competes for space and limits fully functional, cell-dense tissues. This article focuses on bottom-up fabrication of functional tissue by cell sheet engineering. Cell sheet engineering is based on the sequential stacking and adhesion of confluent and organized cell monolayers from two-dimensional cell culture without the need for artifical scaffolds or structural intermediates. The resulting functional cellular monolayers (either individually or as stacked sheets) can then be directly implanted into living systems. Clinical successes are highlighted as well as attempts to overcome the vascularization limit often observed in engineered tissues.
A large fraction of core-collapse supernovae are thought to result in the birth of a rotation-powered pulsar, which is later observable as a radio pulsar up to great ages. The birth properties of these pulsars, and in particular the distribution of their initial rotation periods, are however difficult to infer from studies of the radio pulsar population in our Galaxy. Yet the distributions of their birth properties is an important assumption for scenarios in which ultra-high-energy cosmic rays (UHECRs) originate in very young, extragalactic pulsars with short birth periods and/or high magnetic fields.
Using a model of the very young pulsar wind nebula’s dynamical and spectral evolution, with pulsar wind and accelerated particle parameters assumed similar to those inferred from modeling young pulsar wind nebulae (PWNe) in our Galaxy, we show that X-ray observations of supernovae, a few years to decades after the explosion, constitute a favored window to obtain meaningful constraints on the initial spin-down luminosity of the newly-formed pulsar. We examine the expected emerging PWN spectral component, taking into account the X-ray opacity of the expanding supernova ejecta, and find that it is typically best detectable in < 10 keV X-rays some years after the explosion. We use this framework to assess available X-ray observations and flux upper limits on supernovae, building on the work of Perna et al. (2008). We note that a resulting limit on spin-down luminosity corresponds univocally to a limit on the maximum magnetospheric acceleration potential, irrespective of the specific combination of magnetic field and rotation period that achieves it. We use available X-ray observations of supernovae to place constraints on the birth spin-down luminosity and period distribution of classical pulsars. We also examine the case of magnetars, born with much higher magnetic fields, and show that their much shorter initial spin-down time implies that any plausible signature of young magnetar wind nebulae can only be observed in harder X-ray or gamma-rays.
Caring is a fundamental tenet of healthcare. Caring ‘too much’ can result in compassion fatigue syndrome and is often linked to burnout and low morale. The objective of this study was to examine compassion fatigue, secondary traumatic stress (STS) and burnout by investigating the relationship between levels of compassion (compassion satisfaction) and STS and burnout. The study also aimed to identify radiation therapist (RTTs) groups who may be at risk for developing (STS) and burnout. Finally, we investigated the level of social support that RTTs receive.
RTTs practicing across Canada were invited to participate in an electronic questionnaire. The questionnaire consisted of: demographic information including health-related issues and occupational variables; the Professional Quality of Life Compassion Satisfaction and Fatigue Questionnaire (ProQOL-V) to assess the potential for compassion satisfaction and vulnerability for STS and burnout; and the Multidimensional Scale of Perceived Social Support (MSPSS) to examine the level and sources of social support. A two-way ANOVA was performed to test the statistical significance between varying groups within the study population. A linear regression analysis using potential co-factors was used to test correlations between compassion fatigue, compassion satisfaction and burnout and variables in age, education, years of experience and levels of caring to patients.
A total of 477 survey responses were received representing a 36% response rate. Results of the regression analyses generally indicate inverse correlations between the risks associated with compassion satisfaction, burnout and STS compared with the independent study variables of age, education, years of experience and levels of caring to patients. It was observed that responses were not linear within subgroups (age groups, education classifications, years of study).
RTTs practicing in Canada have a substantial social support network and demonstrate high levels of compassion satisfaction in their daily practice. The results of the study indicate that compassion levels are inversely correlated with burnout and compassion fatigue, although some groups may be at higher risk than others. A possible risk catalyst for compassion fatigue and burnout is associated with underdeveloped managerial workplace support programmes.
We present a new approach to prepare Transmission Electron Microscopy (TEM) nanowire (NW) samples that addresses the core drawbacks of conventional techniques, which are based on mechanical polishing. The proposed method is time efficient and uses XeF2 isotropic and selective dry etching of Si to remove the host substrate from the NWs, after their embedding into a poly(methyl-methacrylate) (PMMA) matrix. Scanning electron microscopy (SEM) data suggest that NWs were grown through the gaps between the parasitic layer islands and that the stems are in direct contact with the Si substrate. This technique does not adversely affect the NWs and offers a convenient means of transferring the GaAs NWs onto other surfaces for post-process TEM analysis. It also offers excellent potential to facilitate their integration into device fabrication via a bottom-up approach, using the PMMA layer as a transfer medium.
Eating behaviour traits of rigid control and disinhibition have been associated with body weight in both adults and adolescents. Moreover, adults reporting a dieting history have increased levels of unhealthy eating behaviours. Against this background, the present study aimed to examine the relationship between dieting history and eating behaviour traits in adolescents. For the purpose of this research, a total of sixty adolescents (aged 15 (sem 2·4) years) from the Québec Family Study completed the Three-Factor Eating Questionnaire (TFEQ) and a questionnaire regarding eating habits. Self-reported current and past dieting were analysed against eating behaviour traits measured by the TFEQ, including all subscales. As the results revealed, few adolescents reported currently dieting (n 3). Adolescents who reported a dieting history (23·3 %) were older (16·9 v. 14·4 years, P < 0·001), were more likely to be female (78·6 v. 41·3 %, P < 0·05) but did not have a significantly higher BMI z-score (1·5 v. 0·9, P = 0·10), although they were more likely to be either overweight or obese (P < 0·01). After correcting for sex, BMI and age, adolescents who reported a dieting history had higher levels of rigid control and disinhibition (P < 0·05–0·0001) than those reporting no dieting history. A greater proportion of adolescents characterised by high rigid control and high disinhibition were past dieters, compared to those characterised by low levels of both behaviour traits (53 v. 4 %). The study arrived at the following conclusions: as observed in adults, adolescents with a history of dieting present unfavourable eating behaviour traits. These behavioural traits may represent an additional challenge to the long-term regulation of body weight.
The successful modification of the tips of a cellular microgripper into ion selective electrodes capable of sensing calcium ions at concentrations as low as 8x10-5 M is described. The modification involves applying the process of adding the components of all solid state ion selective electrodes. Specifically, poly(3,4-ethylenedioxythiophene) (PEDOT) is added to a gold electrode protruding from the microgripper tip; this is then coated with a poly(vinyl chloride) PVC based calcium selective membrane. Excellent Nernstian response was observed from our devices, with calibration slopes of 29.5 ± 2.5 mV/dec.
This work presents the successful fabrication of a thermally actuated U-shaped microgripper that has been specially designed to enable low voltage operation for bidirectional in plane deflection. The microgripper tips are carefully designed to match the biological species being manipulated, which has been demonstrated by the successful manipulation of 10 – 40 μm diameter particles used to simulate biological cells.
This work presents the successful production, via a simple oxidation process, of Ti-TiOx-Pt Metal-Oxide-Metal diodes with excellent electrical asymmetry. TEM analysis has been used to verify the oxide thickness. A thicker layer produces better diodes, although they are of a less uniform nature. The conduction mechanism in these diodes is still under investigation.
Biologically relevant lipid bilayers supported on highly ordered pyrolytic graphite (HOPG) were probed both mechanically and electrically with a Conductive Atomic Force Microscope (C-AFM) capable of measuring ultra-low currents. Results show that these membranes undergo an elastic response up to 26 nN on average when compressed with an AFM tip. Measuring the films with a low contact force demonstrates that contact mode AFM can be used repeatedly to image without damaging the film. Based on current-voltage measurements made with the C-AFM, it is shown that apparently high resistances seen for the films could be the result of variable electrical contact between the tip and surface. As a result, the paper proposes that the deflection of the cantilever should always be measured in order to ensure knowledge of the location of the tip during all electrical measurements.