1,348 research outputs found
Neurocognitive phenomics: examining the genetic basis of cognitive abilities
Cognitive deficits are core to the disability associated with many psychiatric disorders. Both variation in cognition and psychiatric risk show substantial heritability, with overlapping genetic variants contributing to both. Unsurprisingly, therefore, these fields have been mutually beneficial : just as cognitive studies of psychiatric risk variants may identify genes involved in cognition, so too can genome-wide studies based on cognitive phenotypes lead to genes relevant to psychiatric aetiology. The purpose of this review is to consider the main issues involved in the phenotypic characterization of cognition, and to describe the challenges associated with the transition to genome-wide approaches. We conclude by describing the approaches currently being taken by the international consortia involving many investigators in the field internationally (e. g. Cognitive Genomics Consortium; COGENT) to overcome these challenges.</p
Means and covariance functions for geostatistical compositional data: an axiomatic approach
This work focuses on the characterization of the central tendency of a sample
of compositional data. It provides new results about theoretical properties of
means and covariance functions for compositional data, with an axiomatic
perspective. Original results that shed new light on the geostatistical
modeling of compositional data are presented. As a first result, it is shown
that the weighted arithmetic mean is the only central tendency characteristic
satisfying a small set of axioms, namely continuity, reflexivity and marginal
stability. Moreover, this set of axioms also implies that the weights must be
identical for all parts of the composition. This result has deep consequences
on the spatial multivariate covariance modeling of compositional data. In a
geostatistical setting, it is shown as a second result that the proportional
model of covariance functions (i.e., the product of a covariance matrix and a
single correlation function) is the only model that provides identical kriging
weights for all components of the compositional data. As a consequence of these
two results, the proportional model of covariance function is the only
covariance model compatible with reflexivity and marginal stability
Iron bioavailability in two commercial cultivars of wheat: a comparison between wholegrain and white flour and the effects of nicotianamine and 2'-deoxymugineic acid on iron uptake into Caco-2 cells
Iron bioavailability in unleavened white and wholegrain bread made from two commercial wheat varieties was assessed by measuring ferritin production in Caco-2 cells. The breads were subjected to simulated gastrointestinal digestion and the digests applied to the Caco-2 cells. Although Riband grain contained a lower iron concentration than Rialto, iron bioavailability was higher. No iron was taken up by the cells from white bread made from Rialto flour or from wholegrain bread from either variety, but Riband white bread produced a small ferritin response. The results probably relate to differences in phytate content of the breads, although iron in soluble monoferric phytate was demonstrated to be bioavailable in the cell model. Nicotianamine, an iron chelator in plants involved in iron transport, was a more potent enhancer of iron uptake into Caco-2 cells than ascorbic acid or 2'-deoxymugineic acid, another metal chelator present in plants
Design of interactive visualization of models and students data
This document reports the design of the interactive visualizations of open student models that will
be performed in GRAPPLE. The visualizations will be based on data stored in the domain model and student model, and aim at supporting learners to be more engaged in the learning process, and instructors in assisting the learners
Propagation of Bamboo as Blackbird Lure Roost Habitat
Bamboo and native cane species have been suggested as optimal lure roost habitat for shifting blackbird winter roosts away from objectionable urban/suburban sites. As the second phase in developing this potential concept of alleviating conflicts with blackbirds, we report on information gathered from the literature, consultations with bamboo horticulturists, and on-site visits to previously developed bamboo plantations to select desirable species of bamboo for this purpose, and to identify preferred propagating techniques. Bamboo species Phyllostachys rubromarginata and P. nigra henonis ranked highest in terms of greatest cold tolerance, greatest propensity for lateral spreading, and most suitable structure characteristics for maximizing blackbird roosting population densities. The planting of selected rhizome cuttings at 5 X 5 m (16 X 16 ft.) spacing in the early spring was found to be the most practical method of successfully developing desirable roosting habitat in 3-4 years. Other considerations in propagating and managing bamboo as blackbird roosting habitat are discussed
ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries
This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors
Temporal Use Patterns of Wintering Starlings at a Southeastern Livestock Farm: Implications for Damage Control
The farm use patterns of individually marked and transmitter-equipped starlings at a livestock farm in south-central Kentucky were studied each month during the principal damage period (December-February) of 1982-83 and 1984-85 following a pilot study in January and February of 1980. In addition to intensive observation at the farm, sightings of tagged starlings away from the farm were solicited from the public and mapped. For each year of data on individual starlings that used the farm at least once after marking, the expected frequencies of farm occurrence were calculated and compared to observed frequencies. In all 3 years, there was a significant (P \u3c 0.01) heterogeneity among birds in their frequency of farm use. The observed frequencies of daily farm use appeared bimodal suggesting starling subpopulations of frequent versus infrequent farm users. The preponderance of individuals occurred at the farm infrequently. Analysis of starling foraging patterns indicated that frequent farm visitors were also likely to use livestock feed sites more often than infrequent visitors. In 1984-85 the monthly starling turnover at the farm was calculated at 70.3% from December to January and 67.4% from January to February. Data on marked starling sightings away from the farm indicated that these individuals only moved a median distance of only 2.7 km from the farm suggesting a strong fidelity to their foraging area near the farm. The management implications of these data are discussed relative to integrated strategies of starling damage reduction at livestock farms in the southeastern United States
Cross-sectional observational study of 208 patients with non-classical urea cycle disorders.
Urea cycle disorders (UCDs) are inherited disorders of ammonia detoxification often regarded as mainly of relevance to pediatricians. Based on an increasing number of case studies it has become obvious that a significant number of UCD patients are affected by their disease in a non-classical way: presenting outside the newborn period, following a mild course, presenting with unusual clinical features, or asymptomatic patients with only biochemical signs of a UCD. These patients are surviving into adolescence and adulthood, rendering this group of diseases clinically relevant to adult physicians as well as pediatricians. In preparation for an international workshop we collected data on all patients with non-classical UCDs treated by the participants in 20 European metabolic centres. Information was collected on a cohort of 208 patients 50% of which were ≥ 16 years old. The largest subgroup (121 patients) had X-linked ornithine transcarbamylase deficiency (OTCD) of whom 83 were female and 29% of these were asymptomatic. In index patients, there was a mean delay from first symptoms to diagnosis of 1.6 years. Cognitive impairment was present in 36% of all patients including female OTCD patients (in 31%) and those 41 patients identified presymptomatically following positive newborn screening (in 12%). In conclusion, UCD patients with non-classical clinical presentations require the interest and care of adult physicians and have a high risk of neurological complications. To improve the outcome of UCDs, a greater awareness by health professionals of the importance of hyperammonemia and UCDs, and ultimately avoidance of the still long delay to correctly diagnose the patients, is crucial
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