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Measuring multiple 17O–13C J-couplings in naphthalaldehydic acid: a combined solid state NMR and density functional theory approach
A combined multinuclear solid state NMR and gauge included projected augmented wave, density functional theory (GIPAW DFT) computational approach is evaluated to determine the four heteronuclear 1J(13C,17O) couplings in solid 17O enriched naphthalaldehydic acid. Direct multi-field 17O magic angle spinning (MAS), triple quantum MAS (3QMAS) and double rotation (DOR) experiments are initially utilised to evaluate the accuracy of the DFT approximations used in the calculation of the isotropic chemical shifts (diso), quadrupole coupling constants (CQ) and asymmetry (ZQ) parameters. These combined approaches give diso values of 313, 200 and 66 ppm for the carbonyl (CQO), ether (–O–) and hydroxyl (–OH) environments, respectively, with the corresponding measured quadrupole products (PQ) being 8.2, 9.0 and 10.6 MHz. The geometry optimised DFT structure derived using the CASTEP code gives firm agreement with the shifts observed for the ether (diso = 223, PQ = 9.4 MHz) and hydroxyl (diso = 62, PQ = 10.5 MHz) environments but the unoptimised experimental XRD structure has better agreement for the carbonyl group (diso = 320, PQ = 8.3 MHz). The determined diso and ZQ values are shown to be consistent with bond lengths closer to 1.222 Å (experimental length) rather than the geometry optimised length of 1.238 Å. The geometry optimised DFT 1J(13C,17O) coupling to the hydroxyl is calculated as 20 Hz and the couplings to the ether were calculated to be 37 (O–CQO) and 32 (O–C–OH) Hz. The scalar coupling parameters for the unoptimised experimental carbonyl group predict a 1J(13C,17O) value of 28 Hz, whilst optimisation gives a value of 27 Hz. These calculated 1J(13C,17O) couplings, together with estimations of the probability of each O environment being isotopically labelled (determined by electrospray ionisation mass spectrometry) and the measured refocussable transverse dephasing (T2 0) behaviour, are combined to simulate the experimental decay behaviour. Good agreement between the measured and calculated decay behaviour is observed
A cross-sectional study of memory and executive functions in patients with sporadic inclusion body myositis
INTRODUCTION: Sporadic inclusion body myositis (IBM) is a degenerative and inflammatory acquired myopathy characterised by muscle deposition of various proteins typically associated with Alzheimer's disease and other neurodegenerative diseases. While cognitive impairment is not noted as a clinical feature of IBM, evidence is lacking. We aimed to investigate whether cognitive performance of patients with IBM differs from population norms, focussing on cognitive domains affected in early Alzheimer's disease (memory, executive function), and to test whether disease duration and the level of disability of IBM are associated with cognitive function. METHODS: Twenty-four patients with IBM (mean [SD] age 62.0 [7.2] years; disease duration 9.6 [4.8] years) were assessed cross-sectionally on neuropsychological tests covering multiple cognitive domains, including the Preclinical Alzheimer Cognitive Composite (PACC). Performance was compared to published normative data adjusted for age, sex and education (National Alzheimer's Coordinating Center; N = 3268). Associations were examined between PACC score, disease duration and level of disability (assessed using the IBM Functional Rating Scale [IBMFRS]). RESULTS: Across all cognitive tests, group performance was within ±1SD of the normative mean. There was no evidence of associations between PACC score and either disease duration (ρ = -0.04, p = 0.87) or IBMFRS total score (ρ = 0.14, p = 0.52). DISCUSSION: Memory and executive function in patients with IBM did not differ from normative data, and we observed no evidence of associations between the cognitive composite and disease duration or level of disability. This addresses a question frequently asked by patients, and will be of value for clinicians and patients alike. This article is protected by copyright. All rights reserved
TUIs vs. GUIs : comparing the learning potential with preschoolers
In an effort to better understand the learning
potential of a tangible interface, we conducted a comparison study between a tangible and a traditional graphical user interface for teaching preschoolers (In Portugal, children enter preschool at the age of three and they attend it till entering school, normally at the age of six) about good oral hygiene. The study was carried with two groups of children aged 4 to 5 years. Questionnaires to parents, children’s drawings, and interviews were used for data collection and analysis and revealed important indicators about children’s change of attitude, involvement, and preferences for the interfaces. The questionnaires showed a remarkable change of attitude toward tooth brushing in the children that interacted with the tangible interface; particularly children’s motivation increased significantly. Children’s drawings were used to assess their degree of involvement with the interfaces. The drawings from the children that interacted with the tangible interface were very complete and detailed suggesting that the children felt actively involved with the experience. The results suggest that the tangible interface was capable of promoting a stronger and long-lasting involvement having a greater potential to engage children, therefore potentially promoting learning. Evaluation through drawing seems to be a promising method to work with preliterate children; however,it is advisable to use it together with other methods.Fundação para a Ciência e Tecnologia (FCT
Negotiating the transition from adolescence to motherhood: Coping with prenatal and parenting stress in teenage mothers in Mulago hospital, Uganda
<p>Abstract</p> <p>Background</p> <p>Adolescence is a transitional stage from childhood to adulthood that is characterized by physical, physiological, psychosocial and behavioral changes that are influenced to a large extent by the age, culture and socialization of the individual. To explore what adolescent mothers perceive as their struggles during the period of transition from childhood to parenthood (through motherhood) and to describe strategies employed in coping with stress of pregnancy, motherhood and parenthood.</p> <p>Methods</p> <p>Longitudinal qualitative study involving twenty two in-depth interviews and six focus group discussions among pregnant adolescents who were followed from pregnant to delivery, from January 2004 to August 2005. Participant were selected by theoretical sampling and data was analyzed using grounded theory.</p> <p>Results</p> <p>Overall, young adolescents reported more anxiety, loss of self esteem (when they conceived), difficulty in accessing financial, moral and material support from parents or partners and stigmatization by health workers when they sought care from health facilities. Three strategies by which adolescent mothers cope with parenting and pregnancy stress that were described as utilizing opportunities (thriving), accommodating the challenges (bargaining and surviving), or failure (despairing), and varied in the extent to which they enabled adolescents to cope with the stress.</p> <p>Conclusion</p> <p>Adolescents on the transition to motherhood have variable needs and aspirations and utilize different strategies to cope with the stress of pregnancy and parenthood.</p
Quantifying the Spatial Dimension of Dengue Virus Epidemic Spread within a Tropical Urban Environment
Global trends in population growth and human redistribution and movement have reshaped the map of dengue transmission risk, exposing a significant proportion of the world's population to the threat of dengue epidemics. Knowledge on the relative contribution of vector and human movement to the widespread and explosive nature of dengue epidemic spread within an urban environment is limited. By analyzing a very detailed dataset of a dengue epidemic that affected the Australian city of Cairns we performed a comprehensive quantification of the spatio-temporal dimensions of dengue virus epidemic transmission and propagation within a complex urban environment. Space and space-time analysis and models allowed derivation of detailed information on the pattern of introduction and epidemic spread of dengue infection within the urban space. We foresee that some of the results and recommendations derived from our study may also be applicable to many other areas currently affected or potentially subject to dengue epidemics
Capturing egocentric biases in reference reuse during collaborative dialogue
Words that are produced aloud—and especially self-produced ones—are remembered better than words that are not, a phenomenon labeled the production effect in the field of memory research. Two experiments were conducted to determine whether this effect can be generalized to dialogue, and how it might affect dialogue management. Triads (Exp. 1) or dyads (Exp. 2) of participants interacted to perform a collaborative task. Analyzing reference reuse during the interaction revealed that the participants were more likely to reuse the references that they had presented themselves, on the one hand, and those that had been accepted through verbatim repetition, on the other. Analyzing reference recall suggested that the greater accessibility of self-presented references was only transient. Moreover, among partner-presented references, those discussed while the participant had actively taken part in the conversation were more likely to be recalled than those discussed while the participant had been inactive. These results contribute to a better understanding of how individual memory processes might contribute to collaborative dialogue
ASNC/AHA/ASE/EANM/HFSA/ISA/SCMR/SNMMI expert consensus recommendations for multimodality imaging in cardiac amyloidosis: Part 2 of 2—Diagnostic criteria and appropriate utilization
Cardiac amyloidosis is emerging as an underdiagnosed cause of heart failure and mortality. Growing literature suggests that a noninvasive diagnosis of cardiac amyloidosis is now feasible. However, the diagnostic criteria and utilization of imaging in cardiac amyloidosis are not standardized. In this paper, Part 2 of a series, a panel of international experts from multiple societies define the diagnostic criteria for cardiac amyloidosis and appropriate utilization of echocardiography, cardiovascular magnetic resonance imaging, and radionuclide imaging in the evaluation of patients with known or suspected cardiac amyloidosis
ASNC/AHA/ASE/EANM/HFSA/ISA/SCMR/SNMMI expert consensus recommendations for multimodality imaging in cardiac amyloidosis: Part 1 of 2—evidence base and standardized methods of imaging
Cardiac amyloidosis is a form of restrictive infiltrative cardiomyopathy that confers significant mortality. Due to the relative rarity of cardiac amyloidosis, clinical and diagnostic expertise in the recognition and evaluation of individuals with suspected amyloidosis is mostly limited to a few expert centers. Electrocardiography, echocardiography, and radionuclide imaging have been used for the evaluation of cardiac amyloidosis for over 40 years.1-3 Although cardiovascular magnetic resonance (CMR) has also been in clinical practice for several decades, it was not applied to cardiac amyloidosis until the late 1990s. Despite an abundance of diagnostic imaging options, cardiac amyloidosis remains largely underrecognized or delayed in diagnosis.4 While advanced imaging options for noninvasive evaluation have substantially expanded, the evidence is predominately confined to single-center small studies or limited multicenter larger experiences, and there continues to be no clear consensus on standardized imaging pathways in cardiac amyloidosis. This lack of guidance is particularly problematic given that there are numerous emerging therapeutic options for this morbid disease, increasing the importance of accurate recognition at earlier stages. Imaging provides non-invasive tools for follow-up of disease remission/progression complementing clinical evaluation. Additional areas not defined include appropriate clinical indications for imaging, optimal imaging utilization by clinical presentation, accepted imaging methods, accurate image interpretation, and comprehensive and clear reporting. Prospective randomized clinical trial data for the diagnosis of amyloidosis and for imaging-based strategies for treatment are not available. A consensus of expert opinion is greatly needed to guide the appropriate clinical utilization of imaging in cardiac amyloidosis
ASNC/AHA/ASE/EANM/HFSA/ISA/SCMR/SNMMI Expert Consensus Recommendations for Multimodality Imaging in Cardiac Amyloidosis: Part 2 of 2—Diagnostic Criteria and Appropriate Utilization
Cardiac amyloidosis is emerging as an underdiagnosed cause of heart failure and mortality. Growing literature suggests that a noninvasive diagnosis of cardiac amyloidosis is now feasible. However, the diagnostic criteria and utilization of imaging in cardiac amyloidosis are not standardized. In this paper, Part 2 of a series, a panel of international experts from multiple societies define the diagnostic criteria for cardiac amyloidosis and appropriate utilization of echocardiography, cardiovascular magnetic resonance imaging, and radionuclide imaging in the evaluation of patients with known or suspected cardiac amyloidosis
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