Longitudinal multivariate tensor- and searchlight-based morphometry using permutation testing

Tensor based morphometry [1] was used to detect statistically significant regions of neuroanatomical change over time in a comparison between 36 probable Alzheimer's Disease patients and 20 age- and sexmatched controls. Baseline and twelve-month repeat Magnetic Resonance images underwent tied spatial normalisation [10] and longitudinal high-dimensional warps were then estimated. Analyses involved univariate and multivariate data derived from the longitudinal deformation fields. The most prominent findings were expansion of the fluid spaces, and contraction of the hippocampus and temporal region. Multivariate measures were notably more powerful, and have the potential to identify patterns of morphometric difference that would be overlooked by conventional mass-univariate analysis

Towards structured sharing of raw and derived neuroimaging data across existing resources

Data sharing efforts increasingly contribute to the acceleration of scientific discovery. Neuroimaging data is accumulating in distributed domain-specific databases and there is currently no integrated access mechanism nor an accepted format for the critically important meta-data that is necessary for making use of the combined, available neuroimaging data. In this manuscript, we present work from the Derived Data Working Group, an open-access group sponsored by the Biomedical Informatics Research Network (BIRN) and the International Neuroimaging Coordinating Facility (INCF) focused on practical tools for distributed access to neuroimaging data. The working group develops models and tools facilitating the structured interchange of neuroimaging meta-data and is making progress towards a unified set of tools for such data and meta-data exchange. We report on the key components required for integrated access to raw and derived neuroimaging data as well as associated meta-data and provenance across neuroimaging resources. The components include (1) a structured terminology that provides semantic context to data, (2) a formal data model for neuroimaging with robust tracking of data provenance, (3) a web service-based application programming interface (API) that provides a consistent mechanism to access and query the data model, and (4) a provenance library that can be used for the extraction of provenance data by image analysts and imaging software developers. We believe that the framework and set of tools outlined in this manuscript have great potential for solving many of the issues the neuroimaging community faces when sharing raw and derived neuroimaging data across the various existing database systems for the purpose of accelerating scientific discovery

Ultimate loads and response analysis of a monopile supported offshore wind turbine using fully coupled simulation

This PhD research is funded by Lloyd’s Register Group Services Ltd., Aberdeen. Sriramula’s work within the Lloyd’s Register Foundation Centre for Safety and Reliability Engineering at the University of Aberdeen is supported by Lloyd’s Register Foundation. The Foundation helps to protect life and property by supporting engineering-related education, public engagement and the application of research. We would also like to acknowledge the constant assistance provided by Jason Jonkman on using FAST.Peer reviewedPostprin

The stability of weight status through the early to middle childhood years in Australia: a longitudinal study

OBJECTIVES: To investigate the sociodemographic and behavioural factors associated with incidence, persistence or remission of obesity in a longitudinal sample of Australian children aged 4-10 years. SETTING: Nationally representative Longitudinal Study of Australian Children (LSAC). PARTICIPANTS: The sample for this analysis included all children in the Kinder cohort (aged 4-5 years at wave 1) who participated in all four waves of LSAC (wave 1, 2004, aged 4-5 years; wave 2, 2006, aged 6-7 years; wave 3, 2008, aged 8-9 years and wave 4, 2010, aged 10-11 years). Of the 4983 children who participated in the baseline (wave 1) survey, 4169 (83.7%) children completed all four waves of data collection. PRIMARY AND SECONDARY OUTCOME MEASURES: Movement of children between weight status categories over time and individual-level predictors of weight status change (sociodemographic characteristics, selected dietary and activity behaviours). RESULTS: The study found tracking of weight status across this period of childhood. There was an inverse association observed between socioeconomic position and persistence of overweight/obesity. Sugar-sweetened beverages and fruit and vegetable intake and screen time appeared to be important predictors of stronger tracking. CONCLUSIONS: Overweight and obesity established early in childhood tracks strongly to the middle childhood years in Australia, particularly among children of lower socioeconomic position and children participating in some unhealthy behaviour patterns

Release and Establishment of Megamelus scutellaris (Hemiptera: Delphacidae) on Waterhyacinth in Florida

More than 73,000 Megamelus scutellaris (Hemiptera: Delphacidae) were released in Florida over a 2 to 3 yr period at 10 sites in an attempt to establish sustainable populations on waterhyacinth, Eichhornia crassipes Mart. Solms (Commelinales: Pontederiaceae). Insect populations persisted at most sites including those furthest north and consecutive overwintering was confirmed in as many as three times at some sites. Establishment appeared to be promoted at sites with some cover or shading compared to open areas. Insects readily dispersed over short distances which made detection and monitoring difficultFil: Tipping, Philip W.. Invasive Plant Research Laboratory; Estados UnidosFil: Sosa, Alejandro Joaquín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación para el Estudio de Especies Invasivas; ArgentinaFil: Pokorny, Eileen N.. Invasive Plant Research Laboratory; Estados UnidosFil: Foley, Jeremiah. Invasive Plant Research Laboratory; Estados UnidosFil: Schmitz, Don C.. Florida Fish and Wildlife Conservation Commission; Estados UnidosFil: Lane, Jon S.. U.S. Army Corps of Engineers; Estados UnidosFil: Rodgers, Leroy. South Florida Water Management District; Estados UnidosFil: Mccloud, Lori. St. Johns River Water Management District; Estados UnidosFil: Livingston-Way, Pam. St. Johns River Water Management District; Estados UnidosFil: Cole, Matthew S.. St. Johns River Water Management District; Estados UnidosFil: Nichols, Gary. St. Johns River Water Management District; Estados Unido

Diagnosing observation error correlations for Doppler radar radial winds in the Met Office UKV model using observation-minus-background and observation-minus-analysis statistics

With the development of convection-permitting numerical weather prediction the efficient use of high-resolution observations in data assimilation is becoming increasingly important. The operational assimilation of these observations, such as Doppler radar radial winds (DRWs), is now common, though to avoid violating the assumption of uncorrelated observation errors the observation density is severely reduced. To improve the quantity of observations used and the impact that they have on the forecast requires the introduction of the full, potentially correlated, error statistics. In this work, observation error statistics are calculated for the DRWs that are assimilated into the Met Office high-resolution UK model using a diagnostic that makes use of statistical averages of observation-minus-background and observation-minus-analysis residuals. This is the first in-depth study using the diagnostic to estimate both horizontal and along-beam observation error statistics. The new results obtained show that the DRW error standard deviations are similar to those used operationally and increase as the observation height increases. Surprisingly the estimated observation error correlation length-scales are longer than the operational thinning distance. They are dependent both on the height of the observation and on the distance of the observation away from the radar. Further tests show that the long correlations cannot be attributed to the background error covariance matrix used in the assimilation, although they are, in part, a result of using superobservations and a simplified observation operator. The inclusion of correlated error statistics in the assimilation allows less thinning of the data and hence better use of the high-resolution observations

Age and sex-specific rates of leaf regeneration in the Mojave Desert moss Syntrichia caninervis

The extremely skewed female-biased sex ratio in the desert moss Syntrichia caninervis was investigated by assessing the regeneration capacity of detached leaves. Juvenile, green, yellow-green, and brown leaves equating to approximately 0, 2, 6, and 12 yr of age, respectively, were detached from individuals of S. caninervis collected from 10 field populations and grown in a growth chamber for 58 d at a light intensity of 33–128 µmol · m–2 · s–1. Younger leaves (0–2 yr old) tended to have a greater viability, regenerate more quickly, extend their protonemal filaments farther, produce shoots (gametophores) more quickly, produce more shoots, and accumulate a greater biomass than older leaves (6 and 12 yr old). Among younger leaf classes, regenerating female leaves were more likely to produce a shoot than male leaves and produced more shoots than male leaves. The sexes did not differ significantly in time until protonemal emergence, linear extension of protonemata, or rate of biomass accumulation. However, protonemata of male leaves tended to emerge more quickly and produce a greater total biomass, ultimately consisting mostly of protonemata, than did female leaves. The more rapid proliferation of shoots by female leaf regenerants may help to explain the rarity of males in this species