5,036 research outputs found
Computational neurorehabilitation: modeling plasticity and learning to predict recovery
Despite progress in using computational approaches to inform medicine and neuroscience in the last 30 years, there have been few attempts to model the mechanisms underlying sensorimotor rehabilitation. We argue that a fundamental understanding of neurologic recovery, and as a result accurate predictions at the individual level, will be facilitated by developing computational models of the salient neural processes, including plasticity and learning systems of the brain, and integrating them into a context specific to rehabilitation. Here, we therefore discuss Computational Neurorehabilitation, a newly emerging field aimed at modeling plasticity and motor learning to understand and improve movement recovery of individuals with neurologic impairment. We first explain how the emergence of robotics and wearable sensors for rehabilitation is providing data that make development and testing of such models increasingly feasible. We then review key aspects of plasticity and motor learning that such models will incorporate. We proceed by discussing how computational neurorehabilitation models relate to the current benchmark in rehabilitation modeling – regression-based, prognostic modeling. We then critically discuss the first computational neurorehabilitation models, which have primarily focused on modeling rehabilitation of the upper extremity after stroke, and show how even simple models have produced novel ideas for future investigation. Finally, we conclude with key directions for future research, anticipating that soon we will see the emergence of mechanistic models of motor recovery that are informed by clinical imaging results and driven by the actual movement content of rehabilitation therapy as well as wearable sensor-based records of daily activity
Organisational Culture, Procedural Countermeasures, and Employee Security Behaviour: A Qualitative Study
Purpose: This paper provides new insights about security behaviour in selected U.S. and Irish organisations by investigating how organisational culture and procedural security countermeasures tend to influence employee security actions. An increasing number of information security breaches in organisations presents a serious threat to the confidentiality of personal and commercially sensitive data. While recent research shows that humans are the weakest link in the security chain and the root cause of a great portion of security breaches, the extant security literature tends to focus on technical issues.
Design/methodology/approach: This paper builds on general deterrence theory and prior organisational culture literature. The methodology adapted for this study draws on the analytical grounded theory approach employing a constant comparative method.
Findings: This paper demonstrates that procedural security countermeasures and organisational culture tend to affect security behaviour in organisational settings.
Research limitations/implications: This paper fills the void in information security research and takes its place amongst the very few studies that focus on behavioural as opposed to technical issues.
Practical implications: This paper highlights the important role of procedural security countermeasures, information security awareness, and organisational culture in managing illicit behaviour of employees.
Social implications:
Originality/value: This study extends general deterrence theory in a novel way by including information security awareness in the research model and by investigating both negative and positive behaviours
Exposure to secondhand smoke and cognitive impairment in non-smokers: national cross sectional study with cotinine measurement.
addresses: Department of Public Health and Primary Care, University of Cambridge, Cambridge CB2 2SR. [email protected]: PMCID: PMC2643443types: Journal Article; Multicenter Study; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov'tCopyright © 2009 by the BMJ Publishing Group Ltd. This articles was first published in: BMJ, 2009, Vol. 338, pp. b462 -To examine the association between a biomarker of exposure to secondhand smoke (salivary cotinine concentration) and cognitive impairment
Case-finding in clinical practice: An appropriate strategy for dementia identification?
This is the final version. Available from Elsevier via the DOI in this record.Earlier diagnosis of dementia is increasingly being recognized as a public health priority. As screening is not generally recommended, case-finding in clinical practice is encouraged as an alternative dementia identification strategy. The approaches of screening and case-finding are often confused, with uncertainty about what case-finding should involve and under what circumstances it is appropriate. We propose a formal definition of dementia case-finding with a clear distinction from screening. We critically examine case-finding policy and practice and propose evidence requirements for implementation in clinical practice. Finally, we present a case-finding pathway and discuss the available evidence for best practice at each stage, with recommendations for research and practice. In conclusion, dementia case-finding is a promising strategy but currently not appropriate due to the substantial gaps in the evidence base for several components of this approach.This work was supported by the Halpin Trust (J.M.R., D.J.L., and E.K.), Mary Kinross Charitable Trust (D.J.L. and E.K.), and National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) for the South West Peninsula (D.J.L. and I.L.)
Serum leptin and risk of cognitive decline in elderly italians.
Background: US studies suggest that leptin, a fat-derived hormone, may be protective against the development of dementia. Objective: To investigate the complex relationship between leptin levels and cognitive decline in elderly Italians. Methods: We studied circulating fasting leptin levels in 809 elderly adults free from dementia who participated in the prospective Italian population-based InCHIANTI study between 1998 and 2009 (mean follow-up of 8.0 years). Global cognitive decline was defined as a reduction of ≥5 points on the Mini-Mental State Examination (MMSE). Trail-Making Tests A and B were also incorporated, with cognitive decline defined as discontinued testing or the worst 10% of change from baseline. We also investigated whether any association could be explained by midlife weight and whether cognitive decline was associated with changing leptin levels. Results: The multivariate adjusted relative risk ([RR]; 95% confidence interval [CI]) of cognitive decline on the MMSE was 0.84 (95% CI 0.73–0.97) in relation to baseline sex-standardized log-leptin levels. High leptin levels showed a non-significant trend toward a reduced risk of decline on the Trail-Making Tests A (RR = 0.85, 95% CI 0.71–1.02) and B (RR = 0.90, 0.79–1.02). Adjusting for midlife weight or change in weight did not alter the pattern of results, and cognitive decline was not associated with changing leptin levels. Conclusions: High leptin levels were independently associated with a reduced risk of cognitive decline in elderly Italians.Italian Ministry of HealthU.S. National Institute on AgingAlzheimer’s AssociationNational Institute for Health Research (NIHR)National Institute of Health (Baltimore)National Institute of Health (Maryland)Mary Kinross Charitable TrustJames Tudor FoundationHalpin TrustSir Halley Stewart TrustAge Related Diseases and Health TrustNorman Family Charitable Trus
Towards a More Sustainable Use of Scarce Metals: A Review of Intervention Options along the Metals Life Cycle
In the past few decades, geochemically scarce metals have become increasingly relevant for emerging technologies in domains such as energy supply and storage, information and communication, lighting or transportation, which are regarded as cornerstones in the transition towards a sustainable post-fossil society. Accordingly, the supply risks of scarce metals and possible interventions towards their more sustainable use have been subject to an intense debate in recent studies. In this article, we integrate proposed intervention options into a generic life cycle framework, taking into account issues related to knowledge provision and to the institutional setting. As a result, we obtain a landscape of intervention fields that will have to be further specified to more specific intervention profiles for scarce metals or metals families. The envisioned profiles are expected to have the potential to reduce action contingency and to contribute to meeting the sustainability claims often associated with emerging technologies
Vitamin D and Risk of Neuroimaging Abnormalities.
Vitamin D deficiency has been linked with an increased risk of incident all-cause dementia and Alzheimer's disease. The aim of the current study was to explore the potential mechanisms underlying these associations by determining whether low vitamin D concentrations are associated with the development of incident cerebrovascular and neurodegenerative neuroimaging abnormalities. The population consisted of 1,658 participants aged ≥65 years from the US-based Cardiovascular Health Study who were free from prevalent cardiovascular disease, stroke and dementia at baseline in 1992-93. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were determined by liquid chromatography-tandem mass spectrometry from blood samples collected at baseline. The first MRI scan was conducted between 1991-1994 and the second MRI scan was conducted between 1997-1999. Change in white matter grade, ventricular grade and presence of infarcts between MRI scan one and two were used to define neuroimaging abnormalities. During a mean follow-up of 5.0 years, serum 25(OH)D status was not significantly associated with the development of any neuroimaging abnormalities. Using logistic regression models, the multivariate adjusted odds ratios (95% confidence interval) for worsening white matter grade in participants who were severely 25(OH)D deficient (<25 nmol/L) and deficient (≥25-50 nmol/L) were 0.76 (0.35-1.66) and 1.09 (0.76-1.55) compared to participants with sufficient concentrations (≥50 nmol/L). The multivariate adjusted odds ratios for ventricular grade in participants who were severely 25(OH)D deficient and deficient were 0.49 (0.20-1.19) and 1.12 (0.79-1.59) compared to those sufficient. The multivariate adjusted odds ratios for incident infarcts in participants who were severely 25(OH)D deficient and deficient were 1.95 (0.84-4.54) and 0.73 (0.47-1.95) compared to those sufficient. Overall, serum vitamin D concentrations could not be shown to be associated with the development of cerebrovascular or neurodegenerative neuroimaging abnormalities in Cardiovascular Health Study participants.The Cardiovascular Health Study was supported by contracts HHSN268201200036C, HHSN268200800007C, N01 HC55222, N01HC85079, N01HC85080, N01HC85081, N01HC85082, N01HC85083, N01HC85086, and grant HL080295 from the National Heart, Lung, and Blood Institute (NHLBI), with additional contribution from the National Institute of Neurological Disorders and Stroke (NINDS). Additional support was provided by AG023629, AG20098, AG15928 and HL084443 from the National Institute on Aging (NIA). A full list of principal CHS investigators and institutions can be found at chs-nhlbi.org. Additional support was also provided by NIRG-11-200737 from the Alzheimer’s Association, the Mary Kinross Charitable Trust, the James Tudor Foundation, the Halpin Trust, the Age Related Diseases and Health Trust, and the Norman Family Charitable Trust (to D.J.L.). This research was supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula at the Royal Devon and Exeter NHS Foundation Trust. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health. The National Institutes of Health was involved in the original design and conduct of the Cardiovascular Health Study and in the data collection methods
Modifying the Sum Over Topological Sectors and Constraints on Supergravity
The standard lore about the sum over topological sectors in quantum field
theory is that locality and cluster decomposition uniquely determine the sum
over such sectors, thus leading to the usual theta-vacua. We show that without
changing the local degrees of freedom, a theory can be modified such that the
sum over instantons should be restricted; e.g. one should include only
instanton numbers which are divisible by some integer p. This conclusion about
the configuration space of quantum field theory allows us to carefully
reconsider the quantization of parameters in supergravity. In particular, we
show that FI-terms and nontrivial Kahler forms are quantized. This analysis
also leads to a new derivation of recent results about linearized supergravity.Comment: 17 pages, minor change
Rise in Chronic Defibrillation Energy Requirements Necessitating Implantable Defibrillator Lead System Revision
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72617/1/j.1540-8159.1997.tb03890.x.pd
Detection of genes involved in bud phenology in sessile oak (Quercus petraea Matt. Liebl) combining digital expression analysis and Q-PCR
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