Use of a 3-item short-form version of the Barthel Index for use in stroke: systematic review and external validation

Background and Purpose—There may be a potential to reduce the number of items assessed in the Barthel Index (BI), and shortened versions of the BI have been described. We sought to collate all existing short-form BI (SF-BI) and perform a comparative validation using clinical trial data. Methods—We performed a systematic review across multidisciplinary electronic databases to find all published SF-BI. Our validation used the VISTA (Virtual International Stroke Trials Archive) resource. We describe concurrent validity (agreement of each SF-BI with BI), convergent and divergent validity (agreement of each SF-BI with other outcome measures available in the data set), predictive validity (association of prognostic factors with SF-BI outcomes), and content validity (item correlation and exploratory factor analyses). Results—From 3546 titles, we found 8 articles describing 6 differing SF-BI. Using acute trial data (n=8852), internal reliability suggested redundancy in BI (Cronbach α, 0.96). Each SF-BI demonstrated a strong correlation with BI, modified Rankin Scale, National Institutes of Health Stroke Scale (all ρ≥0.83; P<0.001). Using rehabilitation trial data (n=332), SF-BI demonstrated modest correlation with quality of life measures Stroke Impact Scale and 5 domain EuroQOL (ρ≥0.50, P<0.001). Prespecified prognostic factors were associated with SF-BI outcomes (all P<0.001). Our factor analysis described a 3 factor structure, and item reduction suggested an optimal 3-item SF-BI comprising bladder control, transfer, and mobility items in keeping with 1 of the 3-item SF-BI previously described in the literature. Conclusions—There is redundancy in the original BI; we have demonstrated internal and external validity of a 3-item SF-BI that should be simple to use

The biological embedding of early-life socioeconomic status and family adversity in children's genome-wide DNA methylation.

AimTo examine variation in child DNA methylation to assess its potential as a pathway for effects of childhood social adversity on health across the life course.Materials & methodsIn a diverse, prospective community sample of 178 kindergarten children, associations between three types of social experience and DNA methylation within buccal epithelial cells later in childhood were examined.ResultsFamily income, parental education and family psychosocial adversity each associated with increased or decreased DNA methylation (488, 354 and 102 sites, respectively) within a unique set of genomic CpG sites. Gene ontology analyses pointed to genes serving immune and developmental regulation functions.ConclusionFindings provided support for DNA methylation as a biomarker linking early-life social experiences with later life health in humans

Aging in a Two-Dimensional Ising Model with Dipolar Interactions

Aging in a two-dimensional Ising spin model with both ferromagnetic exchange and antiferromagnetic dipolar interactions is established and investigated via Monte Carlo simulations. The behaviour of the autocorrelation function $C(t,t_w)$ is analyzed for different values of the temperature, the waiting time $t_w$ and the quotient $\delta=J_0/J_d$, $J_0$ and $J_d$ being the strength of exchange and dipolar interactions respectively. Different behaviours are encountered for $C(t,t_w)$ at low temperatures as $\delta$ is varied. Our results show that, depending on the value of $\delta$, the dynamics of this non-disordered model is consistent either with a slow domain dynamics characteristic of ferromagnets or with an activated scenario, like that proposed for spin glasses.Comment: 4 pages, RevTex, 5 postscript figures; acknowledgment added and some grammatical corrections in caption

Modeling sampling strategies for determination of zooplankton abundance in ballast water

Ballast water has been a major source of non-indigenous species introductions. The International Maritime Organization has proposed performance standard that will establish an upper limit for viable organisms in discharged ballast. Here we test different sampling efforts for zooplankton in ballast water on a commercial vessel. We fit different probability density functions to find the most representative and evaluated sampling efforts necessary to achieve error rates (α, β) of \u3c 0.05. Our tests encompassed four seasonal trials and five sample volumes. To estimate error rates, we performed simulations which drew from 1 to 30 replicates of each volume (0.10–3.00m3) for mean densities ranging between 1 and 20 organisms m− 3. Fieldwork and simulations suggested that \u3e 0.5 m3samples had the best accuracy and precision, and that the Poisson distribution fit these communities best. This study provides the first field test of a sampling strategy to assess compliance with the future IMO standard for large vessels. © 2016 Elsevier Lt

Predicting Invasion Risk Using Measures of Introduction Effort and Environmental Niche Models

The Chinese mitten crab (Eriocheir sinensis) is native to east Asia, is established throughout Europe, and is introduced but geographically restricted in North America. We developed and compared two separate environmental niche models using genetic algorithm for rule set prediction (GARP) and mitten crab occurrences in Asia and Europe to predict the species\u27 potential distribution in North America. Since mitten crabs must reproduce in water with ≥15‰ salinity, we limited the potential North American range to freshwater habitats within the highest documented dispersal distance (1260 km) and a more restricted dispersal limit (354 km) from the sea. Applying the higher dispersal distance, both models predicted the lower Great Lakes, most of the eastern seaboard, the Gulf of Mexico and southern extent of the Mississippi River watershed, and the Pacific northwest as suitable environment for mitten crabs, but environmental match for southern states (below 35° N) was much lower for the European model. Use of the lower range with both models reduced the expected range, especially in the Great Lakes, Mississippi drainage, and inland areas of the Pacific Northwest. To estimate the risk of introduction of mitten crabs, the amount of reported ballast water discharge into major United States ports from regions in Asia and Europe with established mitten crab populations was used as an index of introduction effort. Relative risk of invasion was estimated based on a combination of environmental match and volume of unexchanged ballast water received (July 1999–December 2003) for major ports. The ports of Norfolk and Baltimore were most vulnerable to invasion and establishment, making Chesapeake Bay the most likely location to be invaded by mitten crabs in the United States. The next highest risk was predicted for Portland, Oregon. Interestingly, the port of Los Angeles/Long Beach, which has a large shipping volume, had a low risk of invasion. Ports such as Jacksonville, Florida, had a medium risk owing to small shipping volume but high environmental match. This study illustrates that the combination of environmental niche- and vector-based models can provide managers with more precise estimates of invasion risk than can either of these approaches alone

Inhalation of diesel exhaust and allergen alters human bronchial epithelium DNA methylation

Background Allergic disease affects 30% to 40% of the world's population, and its development is determined by the interplay between environmental and inherited factors. Air pollution, primarily consisting of diesel exhaust emissions, has increased at a similar rate to allergic disease. Exposure to diesel exhaust may play a role in the development and progression of allergic disease, in particular allergic respiratory disease. One potential mechanism underlying the connection between air pollution and increased allergic disease incidence is DNA methylation, an epigenetic process with the capacity to integrate gene-environment interactions. Objective We sought to investigate the effect of allergen and diesel exhaust exposure on bronchial epithelial DNA methylation. Methods We performed a randomized crossover-controlled exposure study to allergen and diesel exhaust in humans, and measured single-site (CpG) resolution global DNA methylation in bronchial epithelial cells. Results Exposure to allergen alone, diesel exhaust alone, or allergen and diesel exhaust together (coexposure) led to significant changes in 7 CpG sites at 48 hours. However, when the same lung was exposed to allergen and diesel exhaust but separated by approximately 4 weeks, significant changes in more than 500 sites were observed. Furthermore, sites of differential methylation differed depending on which exposure was experienced first. Functional analysis of differentially methylated CpG sites found genes involved in transcription factor activity, protein metabolism, cell adhesion, and vascular development, among others. Conclusions These findings suggest that specific exposures can prime the lung for changes in DNA methylation induced by a subsequent insult

Magnetic Properties of 2-Dimensional Dipolar Squares: Boundary Geometry Dependence

By means of the molecular dynamics simulation on gradual cooling processes, we investigate magnetic properties of classical spin systems only with the magnetic dipole-dipole interaction, which we call dipolar systems. Focusing on their finite-size effect, particularly their boundary geometry dependence, we study two finite dipolar squares cut out from a square lattice with $\Phi=0$ and $\pi/4$, where $\Phi$ is an angle between the direction of the lattice axis and that of the square boundary. Distinctly different results are obtained in the two dipolar squares. In the $\Phi=0$ square, the ``from-edge-to-interior freezing'' of spins is observed. Its ground state has a multi-domain structure whose domains consist of the two among infinitely (continuously) degenerated Luttinger-Tisza (LT) ground-state orders on a bulk square lattice, i.e., the two antiferromagnetically aligned ferromagnetic chains (af-FMC) orders directed in parallel to the two lattice axes. In the $\Phi=\pi/4$ square, on the other hand, the freezing starts from the interior of the square, and its ground state is nearly in a single domain with one of the two af-FMC orders. These geometry effects are argued to originate from the anisotropic nature of the dipole-dipole interaction which depends on the relative direction of sites in a real space of the interacting spins.Comment: 21 pages, 13 figures, submitted to Journal of Physical Society Japa

Clinical selection strategies to identify ischemic stroke patients with large anterior vessel occlusion: results from SITS-ISTR (Safe Implementation of Thrombolysis in Stroke International Stroke Thrombolysis Registry)

Background and Purpose—The National Institutes of Health Stroke Scale (NIHSS) correlates with presence of large anterior vessel occlusion (LAVO). However, the application of the full NIHSS in the prehospital setting to select patients eligible for treatment with thrombectomy is limited. Therefore, we aimed to evaluate the prognostic value of simple clinical selection strategies. Methods—Data from the Safe Implementation of Thrombolysis in Stroke International Stroke Thrombolysis Registry (January 2012–May 2014) were analyzed retrospectively. Patients with complete breakdown of NIHSS scores and documented vessel status were included. We assessed the association of prehospital stroke scales and NIHSS symptom profiles with LAVO (internal carotid artery, carotid-terminus or M1-segment of the middle cerebral artery). Results—Among 3505 patients, 23.6% (n=827) had LAVO. Pathological finding on the NIHSS item best gaze was strongly associated with LAVO (adjusted odds ratio 4.5, 95% confidence interval 3.8–5.3). All 3 face–arm–speech–time test (FAST) items identified LAVO with high sensitivity. Addition of the item gaze to the original FAST score (G-FAST) or high scores on other simplified stroke scales increased specificity. The NIHSS symptom profiles representing total anterior syndromes showed a 10-fold increased likelihood for LAVO compared with a nonspecific clinical profile. If compared with an NIHSS threshold of ≥6, the prehospital stroke scales performed similarly or even better without losing sensitivity. Conclusions—Simple modification of the face–arm–speech–time score or evaluating the NIHSS symptom profile may help to stratify patients’ risk of LAVO and to identify individuals who deserve rapid transfer to comprehensive stroke centers. Prospective validation in the prehospital setting is required

Reorientation transition of ultrathin ferromagnetic films

We demonstrate that the reorientation transition from out-of-plane to in-plane magnetization with decreasing temperature as observed experimentally in Ni-films on Cu(001) can be explained on a microscopic basis. Using a combination of mean field theory and perturbation theory, we derive an analytic expression for the temperature dependent anisotropy. The reduced magnetization in the film surface at finite temperatures plays a crucial role for this transition as with increasing temperature the influence of the uniaxial anisotropies is reduced at the surface and is enhanced inside the film.Comment: 4 pages(RevTeX), 3 figures (EPS

Bayesian Centroid Estimation for Motif Discovery

Biological sequences may contain patterns that are signal important biomolecular functions; a classical example is regulation of gene expression by transcription factors that bind to specific patterns in genomic promoter regions. In motif discovery we are given a set of sequences that share a common motif and aim to identify not only the motif composition, but also the binding sites in each sequence of the set. We present a Bayesian model that is an extended version of the model adopted by the Gibbs motif sampler, and propose a new centroid estimator that arises from a refined and meaningful loss function for binding site inference. We discuss the main advantages of centroid estimation for motif discovery, including computational convenience, and how its principled derivation offers further insights about the posterior distribution of binding site configurations. We also illustrate, using simulated and real datasets, that the centroid estimator can differ from the maximum a posteriori estimator.Comment: 24 pages, 9 figure