bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predicting alcohol consumption in adolescence from alcohol-specific and general externalizing genetic risk factors, key environmental exposures and their interaction
Authors: Kendler K. S. , Gardner C. , Dick D. M. 
Published: October 2010

BackgroundAlcohol consumption is influenced by specific genetic risk factors for alcohol use disorders (AUDs), non-specific genetic risk factors for externalizing behaviors and various environmental experiences. We have limited knowledge of how these risk factors inter-relate through development.MethodRetrospective assessments in 1796 adult male twins using a life history calendar of key environmental exposures and alcohol consumption from early adolescence to mid-adulthood. Analysis by linear mixed models.ResultsThe importance of non-specific genetic risk factors on maximal alcohol consumption rose rapidly in early to mid-adolescence, peaked at ages 15–17 years and then declined slowly. Alcohol-specific genetic risk factors increased slowly in influence through mid-adulthood. We detected robust evidence for environmental moderation of genetic effects on alcohol consumption that was more pronounced in early and mid-adolescence than in later periods. Alcohol availability, peer deviance and low prosocial behaviors showing the strongest moderation effects. More interactions with environmental risk factors were seen for the non-specific externalizing disorder risk than for specific genetic risk for AUDs.ConclusionsThe impact of specific and non-specific genetic influences on alcohol consumption have different development trajectories. Genetic effects on alcohol use are more pronounced when social constraints are minimized (e.g. low prosocial behaviors or parental monitoring) or when the environment permits easy access to alcohol and/or encourages its use (e.g. high alcohol availability or peer deviance). Gene–environment interactions influencing alcohol intake may be more robust at younger ages, indicating greater plasticity of genetic influences early in the development of drinking patterns.
Executive functioning-related brain abnormalities associated with the genetic liability for schizophrenia: an activation likelihood estimation meta-analysis
Authors: Goghari V. M. 
Published: October 2010

BackgroundRelatives of schizophrenia patients demonstrate abnormalities in prefrontal cortical activation during executive processing as measured by functional neuroimaging, albeit not consistently. A meta-analysis was conducted to determine whether reliable patterns of brain hypo- and hyperactivity, especially in the middle frontal region, were present in the relatives of patients.MethodSeventeen studies, containing 18 samples of relatives and controls, were included in this meta-analysis. Studies were included if relatives of schizophrenia patients were compared to controls, an executive processing task was used, and standard space coordinates were reported for the functional activations. Activation likelihood estimation (ALE) was implemented to find convergence across functional neuroimaging experiment coordinates. A separate analysis was conducted to assess the potential impact of a priori hypothesis testing used in region-of-interest (ROI) approaches on the meta-analysis results.ResultsRelatives demonstrated hypo- and hyperactivity in statistically overlapping right middle frontal regions [Brodmann area (BA) 9/10]. Use of an ROI analysis that a priori focused on prefrontal regions resulted in more findings of reduced activity in the middle frontal region.ConclusionsThe cortical regions identified by this meta-analysis could potentially serve as intermediate biological markers in the search for candidate genes for schizophrenia. As neurocognitive deficits are related to functional impairments in patients, a better understanding of neural and genetic vulnerabilities would be beneficial in our efforts to remediate these important deficits.
Global and regional cortical thinning in first-episode psychosis patients: relationships with clinical and cognitive features
Authors: Crespo-Facorro B. , Roiz-Santiáñez R. , Pérez-Iglesias R. , Rodriguez-Sanchez J. M. , Mata I. , Tordesillas-Gutierrez D. , Sanchez E. , Tabarés-Seisdedos R. , Andreasen N. , Magnotta V. , Vázquez-Barquero J. L. 
Published: October 2010

BackgroundThe thickness of the cortical mantle is a sensitive measure for identifying alterations in cortical structure. We aimed to explore whether first episode schizophrenia patients already show a significant cortical thinning and whether cortical thickness anomalies may significantly influence clinical and cognitive features.MethodWe investigated regional changes in cortical thickness in a large and heterogeneous sample of schizophrenia spectrum patients (n=142) at their first break of the illness and healthy controls (n=83). Magnetic resonance imaging brain scans (1.5 T) were obtained and images were analyzed by using brains2. The contribution of sociodemographic, cognitive and clinical characterictics was investigated.ResultsPatients showed a significant total cortical thinning (F=17.55, d=−0.62, p<0.001) and there was a diffuse pattern of reduced thickness (encompassing frontal, temporal and parietal cortices) (all p's<0.001, d's>0.53). No significant group×gender interactions were observed (all p's>0.15). There were no significant associations between the clinical and pre-morbid variables and cortical thickness measurements (all r's<0.12). A weak significant negative correlation between attention and total (r=−0.24, p=0.021) and parietal cortical thickness (r=−0.27, p=0.009) was found in patients (thicker cortex was associated with lower attention). Our data revealed a similar pattern of cortical thickness changes related to age in patients and controls.ConclusionsCortical thinning is independent of gender, age, age of onset and duration of the illness and does not seem to significantly influence clinical and functional symptomatology. These findings support a primary neurodevelopment disorder affecting the normal cerebral cortex development in schizophrenia.
Metric properties of non-renormalizable S-unimodal maps: II. Quasisymmetric conjugacy classes
Authors: Jakobson M. , Świạtek G. 
Published: October 2010

AbstractIt is shown that for certain classes of S-unimodal maps with aperiodic kneading sequences, the topological conjugacies are also quasisymmetric. This includes some infinitely renormalizable polynomials of unbounded type.
Almost-sure waiting time results for weak and very weak Bernoulli processes
Authors: Marton Katalin , Shields Paul C. 
Published: October 2010

AbstractAlmost-sure convergence of (l/k) log Wk(x, y) to entropy for weak Bernoulli processes is proved, where Wk (x, y) is the waiting time until an initial segment of length k of a sample path x is seen in an independently chosen sample path y. Analogous almost-sure results are obtained in the approximate match case for very weak Bernoulli processes. The weak Bernoulli proof uses recent results obtained by the authors about the estimation of joint distributions, while the very weak Bernoulli result utilizes a new characterization of such processes in terms of a blowing-up property.
Some ergodic properties for infinite graphs associated with subfactors
Authors: Popa Sorin 
Published: October 2010

AbstractWe prove that the restriction of the graph of a subfactor, ΓN,M, to an infinite subset of vertices with finite boundary has the same norm as ΓN,W. In particular, ifNφMis extremal with [M : N] > 4 and ΓN,Mhas an A∞, tail then ΓN, M= A∞.
Horseshoes in the measure-preserving Hénon map
Authors: Brown Ray 
Published: October 2010

AbstractWe show, using elementary methods, that for 0 < a the measure-preserving, orientation-preserving Hénon map, H, has a horseshoe. This improves on the result of Devaney and Nitecki who have shown that a horseshoe exists in this map for a ≥ 8. For a > 0, we also prove the conjecture of Devaney that the first symmetric homoclinic point is transversal.To obtain our results, we show that for a branch, Cu, of the unstable manifold of a hyperbolic fixed point of H, Cu crosses the line y = − x and that this crossing is a homoclinic point, χc. This has been shown by Devaney, but we obtain the crossing using simpler methods. Next we show that if the crossing of Wu(p) and Ws(p) at χc is degenerate then the slope of Cu at this crossing is one. Following this we show that if χc is a degenerate homoclinic its x-coordinate must be greater than l/(2a). We then derive a contradiction from this by showing that the slope of Cu at H-1(χc) must be both positive and negative, thus we conclude that χc is transversal.Our approach uses a lemma that gives a recursive formula for the sign of curvature of the unstable manifold. This lemma, referred to as ‘the curvature lemma’, is the key to reducing the proof to elementary methods. A curvature lemma can be derived for a very broad array of maps making the applicability of these methods very general. Further, since curvature is the strongest differentiability feature needed in our proof, the methods work for maps of the plane which are only C2.
Invariant measures of groups of homeomorphisms and Auslander's conjecture
Authors: Friedland Shmuel 
Published: October 2010

AbstractWe give sufficient conditions for a group of homeomorphisms of a compact Hausdorff space to have an invariant probability measure. For a complex projective spaceCPnwe give a necessary condition for a subgroup of Aut(CPn) to have an invariant probability measure. We discuss two approaches to Auslander's conjecture.
On the approximation of Hénon-like attractors by homoclinic tangencies
Authors: Ures Raúl 
Published: October 2010

AbstractWe prove that the diffeomorphisms with strange attractors shown to exist elsewhere are approximated by diffeomorphisms exhibiting homoclinic tangencies. As a consequence for the Hénon family these diffeomorphisms are approximated by diffeomorphisms exhibiting periodic attractors. This answers a question posed by Benedicks and Carleson.
Entropy for extensions of Bernoulli shifts
Authors: Choda Marie 
Published: October 2010

AbstractWe give a condition for automorphisms α and β on finite von Neumann algebras which induces the tensor product formula for entropies: H(α ⊗ β) = H(α) + H(β). As an application, the Bernoulli shift (1/n, 1/n, …, 1/n) has extensions to ergodic outer automorphisms {αk; k = 1,2, …} on the hyperfinite II1 factor R with the entropies H(αk) = (1/2)kn log n.
Backward continued fractions, Hecke groups and invariant measures for transformations of the interval
Authors: Gröchenig Karlheinz , Haas Andrew 
Published: October 2010

AbstractWe develop a new type of backward continued fractions that can be associated to each Hecke-type group. We study its symbolic dynamics, and the corresponding interval maps and their invariant measures. These measures are infinite if and only if the corresponding groups are discrete. For the discrete Hecke groups the invariant measure is computed explicitly by studying the geodesic flow on the associated Riemann surface.
Julia sets for holomorphic endomorphisms of ℂn
Authors: Heinemann Stefan-M. 
Published: October 2010

AbstractWe give a definition for a Julia setJ(f) for generic classes of polynomial endomorphismsf: ℂn→ ℂn. Forn= 1, our definition is equivalent to the usual one, which gives the points where the iterates offdo not form a normal family. Moreover, the Julia setJ(f1× … ×fn) ⊂ ℂnfor a product of one-dimensional polynomialsfi: ℂ → ℂ turns out to be the productJ(f1) × … ×J(fn) of the associated Julia setsJ(fi) ⊂ ℂ. For a special class of mappingsf: ℂ2→ ℂ2which is not of this simple type, the so-called Cantor skews, we investigate topological structure as well as measure theoretic aspects of the Julia sets obtained using our definition.
On almost everywhere exponential convergence of the modified Jacobi-Perron algorithm: a corrected proof
Authors: Fujita T. , Ito S. , Keane M. , Ohtsuki M. 
Published: October 2010

The following theorem was published in [2].Theorem. There exists a constant δ > 0 such that for Lebesgue almost every (α, β) ∈ X = [0, 1] × [0, 1], there exists no = no(α, β) such that for any n > nowhere the integers pn, qn, rn are provided by the modified Jacobi-Perron algorithm.
Elliptic islands in generalized Sinai billiards
Authors: Donnay Victor J. 
Published: October 2010

AbstractWe find necessary conditions for a generalized Sinai billiard to be ergodic, independent of the geometry of the disks; i.e. if the conditions are not satisfied, then we can always construct special geometries for which the system is not ergodic. We prove non-ergodicity by constructing an elliptic periodic orbit and showing that this orbit satisfies the non-degeneracy condition of KAM theory. By a combination of theory and numerical calculation involving a computer algebra system (Mathematica), we show that the first Birkhoff invariant is non-zero. We apply this result to produce non-ergodic Hamiltonian flows that are generated by smooth potentials of finite range (repelling potentials and Lennard–Jones potentials) and by geodesic flows on the torus.
Planar central configuration estimates in the n-body problem
Authors: McCord Christopher K. 
Published: October 2010

AbstractFor all masses, there are at least n − 2, O2-orbits of non-collinear planar central configurations. In particular, this estimate is valid even if the potential function is not a Morse function. If the potential function is a Morse function, then an improved lower bound, of the order of n! ln(n + 1/3)/2, can be given.
An outbreak ofSalmonellaTyphimurium DT191a associated with reptile feeder mice
Authors: HARKER K. S. , LANE C. , DE PINNA E. , ADAK G. K. 
Published: October 2010

SUMMARYIn December 2008 an increase of tetracycline-resistantSalmonellaTyphimurium definitive phage-type 191a (DT191a) was identified in England and Wales by the reference laboratory. This was confirmed to have a phage-typing pattern that had not previously been seen. Strong statistical evidence for an association between illness and keeping reptiles was demonstrated by a matched case-case study (mOR 16·82, 95% CI 2·78–∞). Questionnaires revealed an association with frozen reptile feeder mice, and mice representing 80% of the UK supply lines were tested for the presence ofSalmonella. DT191a was found in three pools of sampled mice, which were traced back to a single supplier in the USA. Imports from this supplier were halted, and tighter regulations are now in place. A leaflet detailing how to prevent contractingSalmonellafrom pet reptiles has been published as well as updated advice on the Health Protection Agency's website.
Source attribution of human Salmonella cases in Sweden
Authors: WAHLSTRÖM H. , ANDERSSON Y. , PLYM-FORSHELL L. , PIRES S. M. 
Published: October 2010

SUMMARYThe aim of this study was to identify the sources of sporadic domestic Salmonella cases in Sweden and to evaluate the usefulness of a source-attribution model in a country in which food animals are virtually free from Salmonella. The model allocates human sporadic domestic Salmonella cases to different sources according to distribution of Salmonella subtypes in the different sources. Sporadic domestic human Salmonella cases (n=1086) reported between July 2004 and June 2006 were attributed to nine food-animal and wildlife sources. Of all Salmonella cases, 82% were acquired abroad and 2·9% were associated with outbreaks. We estimated that 6·4% were associated with imported food, 0·5% with food-producing animals, and 0·6% with wildlife. Overall, 7·7% could not be attributed to any source. We concluded that domestic food-producing animals are not an important source for Salmonella in humans in Sweden, and that the adapted model is useful also in low-prevalence countries.
Seasonal breeding drives the incidence of a chronic bacterial infection in a free-living herbivore population
Authors: PATHAK A. K. , BOAG B. , POSS M. , HARVILL E. T. , CATTADORI I. M. 
Published: October 2010

SUMMARYUnderstanding seasonal changes in age-related incidence of infections can be revealing for disentangling how host heterogeneities affect transmission and how to control the spread of infections between social groups. Seasonal forcing has been well documented in human childhood diseases but the mechanisms responsible for age-related transmission in free-living and socially structured animal populations are still poorly known. Here we studied the seasonal dynamics ofBordetella bronchisepticain a free-living rabbit population over 5 years and discuss the possible mechanisms of infection. This bacterium has been isolated in livestock and wildlife where it causes respiratory infections that rapidly spread between individuals and persist as subclinical infections. Sera were collected from rabbits sampled monthly and examined using an ELISA. Findings revealed thatB. bronchisepticacirculates in the rabbit population with annual prevalence ranging between 88% and 97%. Both seroprevalence and antibody optical density index exhibited 1-year cycles, indicating that disease outbreaks were seasonal and suggesting that long-lasting antibody protection was transient. Intra-annual dynamics showed a strong seasonal signature associated with the recruitment of naive offspring during the breeding period. Infection appeared to be mainly driven by mother-to-litter contacts rather than by interactions with other members of the community. By age 2 months, 65% of the kittens were seropositive.
Intergenerational risk sharing within funded pension schemes
Authors: CUI JIAJIA , JONG FRANK DE , PONDS EDUARD 
Published: October 2010

AbstractIs intergenerational risk sharing desirable and feasible in funded pension schemes? Using a multi-period OLG model, we study risk sharing between generations for a variety of realistic collective funded pension schemes, where pension benefits and contributions may depend on the funding ratio and the asset returns. We find that well-structured intergenerational risk sharing via collective schemes can be welfare-enhancing vis-à-vis the optimal individual benchmark. Moreover, from an ex ante perspective the expected welfare gain of the current entry cohort is not at the cost of the older and future cohorts.
A Meta-analysis of Studies on Plant Growth Rate and Allocation to Roots and Shoots
Authors: Taub Daniel 
Published: October 2010

AbstractI performed a meta-analysis of studies examining the relationships among nutrient availability, plant growth rate and allocation to roots vs. shoots. Species characteristic of high fertility habits grew faster than species characteristic of less fertile habitats. While species were highly plastic in root/shoot ratio, there was a strong correlation in root/shoot across fertility levels when plants were grown across fertility gradients. This suggests that the proportional mass allocation to roots is a consistent characteristic of individual species relative to other species. There was no consistent relationship between allocation to roots and either growth rate or the fertility of habitats that species typically are found in.
Standards and infrastructure for managing experimental metadata
Authors: Evans Richard , Sansone Susanna-Assunta , Rocca-Serra Philippe , Brandizi Marco , Maguire Eamonn , Sklyar Nataliya , Taylor Chris , Delahaye Manon 
Published: October 2010

Abstract*See also the "related presentation":http://precedings.nature.com/documents/3145/version/1*We present an infrastructure that leverages synergistic reporting standards and ontologies^1,2,3,4,5^ to create a common structured representation and storage mechanism for experimental metadata from biological and biomedical investigations ranging from simple single-assay studies to complex, methodologically diverse multi-assay studies.The infrastructure’s components include: a data capture and editing tool (ISAcreator); validator (ISAvalidator); database (BioInvestigation Index); and converter (ISAconverter); and a BioConductor analysis package (R-ISApackage). The components are designed for local installation, and can work independently, or as unified system.View the "public instance":http://www.ebi.ac.uk/bioinvindex running at EBI and/or "download the components":http://isatab.sf.net for your local use.*References*1. Taylor CF, Field D, Sansone SA,… Rocca-Serra P et al. (2008) The MIBBI Project. Nature Biotechnology Aug;26(8):889-896. "http://www.mibbi.org":http://www.mibbi.org2. Smith B, Ashburner M, Rosse C,… Rocca-Serra P, …Sansone SA et al. (2007) The OBO Foundry. Nature Biotechnology Nov;25(11):1251-5. "http://www.obofoundry.org":http://www.obofoundry.org3. Ontology for Biomedical Investigations (OBI) "http://obi-ontology.org":http://obi-ontology.org4. Sansone SA, Rocca-Serra P, Brandizi M,… Taylor CF et al. (2008) The First MGED RSBI (ISA-TAB) Workshop. OMICS. Jun;12(2):143-9. "http://isatab.sf.net":http://isatab.sf.net5. Jones AR, Miller M, Aebersold R,… Sansone SA et al. (2007) The Functional Genomics Experiment model (FuGE). Nature Biotechnology Oct;25(10):1127-1133. "http://fuge.sf.net":http://fuge.sf.net
Worm Annotation in the UniProt Knowledgebase (UniProtKB)
Authors: Legge Duncan , Consortium UniProt 
Published: October 2010

AbstractThe nematode worm, Caenorhabditis elegans, was the first multicellular organism to be sequenced. Its genome was published in 1998, providing an impetus for gene and protein annotation. Recently, the genome of C. briggsae has been sequenced. This has given bioinformaticans the opportunity to study comparative genomics between two highly similar organisms. Currently, there are 12 species of Caenorhabditis in UniProtKB and over 700 nematode species, including some of interest to parasitology. Functional and sequence annotation from literature and sequence analysis tools are included in each curated record. C. elegans has a relatively small genome size, short life span and a transparent body, making it ideal for knock-out/RNAi studies. Thus many C. elegans UniProtKB entries have characterization details in the newly introduced DISRUPTION PHENOTYPE comment. Many more worm genome sequencing projects are underway, three of which involve species from the Caenorhabditis genus (C. brenneri, C. japonica and C.remanei). We look forward to working with this influx of data and continuing our close collaboration with WormBase.
Normalization and Matching of Chemical Compound Names
Authors: Golebiewski Martin , Šarić Jasmin , Engelken Henriette , Bittkowski Meik , Wittig Ulrike , Müller Wolfgang , Rojas Isabel 
Published: October 2010

AbstractThe identification of a chemical compound solely based on its name requires comprehensive chemical knowledge and often extensive searches in chemical databases. However, it is crucial for the integration of biochemical data extracted from the literature, since many publications exclusively describe a compound by its name. We have developed an application which matches synonymic names of chemical compounds and thereby facilitates the bundling of corresponding data referring to the same compound.The tool that we have developed is based on natural language processing (NLP) methods and applies rules to systematically normalize chemical compound names. Matching of synonymous names is achieved by comparison of the normalized name forms. It is capable of normalizing a given name of a chemical compound and matching it against names in (bio-)chemical databases (e.g. SABIO-RK, ChEBI or PubChem), even when there is no exact name-to-name-match. The tool is also able to match a complete list of compound names against these databases which makes it useful for the automatic annotation of chemical data.This normalization and matching of various synonyms of a chemical compound constitutes a platform for the unambiguous identification of compounds described in the literature or in databases.