658 research outputs found
Treponema denticola in Disseminating Endodontic Infections
Treponema denticola is a consensus periodontal pathogen that has recently been associated with endodontic pathology. In this study, the effect of mono-infection of the dental pulp with T. denticola and with polymicrobial “red-complex” organisms (RC) (Porphyromonas gingivalis, Tannerella forsythia, and T. denticola) in inducing disseminating infections in wild-type (WT) and severe-combined-immunodeficiency (SCID) mice was analyzed. After 21 days, a high incidence (5/10) of orofacial abscesses was observed in SCID mice mono-infected with T. denticola, whereas abscesses were rare in SCID mice infected with the red-complex organisms or in wildtype mice. Splenomegaly was present in all groups, but only mono-infected SCID mice had weight loss. T. denticola DNA was detected in the spleen, heart, and brain of mono-infected SCID mice and in the spleen from mono-infected wild-type mice, which also had more periapical bone resorption. The results indicate that T. denticola has high pathogenicity, including dissemination to distant organs, further substantiating its potential importance in oral and linked systemic conditions
The Human Oral Microbiome Database: a web accessible resource for investigating oral microbe taxonomic and genomic information
The human oral microbiome is the most studied human microflora, but 53% of the species have not yet been validly named and 35% remain uncultivated. The uncultivated taxa are known primarily from 16S rRNA sequence information. Sequence information tied solely to obscure isolate or clone numbers, and usually lacking accurate phylogenetic placement, is a major impediment to working with human oral microbiome data. The goal of creating the Human Oral Microbiome Database (HOMD) is to provide the scientific community with a body site-specific comprehensive database for the more than 600 prokaryote species that are present in the human oral cavity based on a curated 16S rRNA gene-based provisional naming scheme. Currently, two primary types of information are provided in HOMD—taxonomic and genomic. Named oral species and taxa identified from 16S rRNA gene sequence analysis of oral isolates and cloning studies were placed into defined 16S rRNA phylotypes and each given unique Human Oral Taxon (HOT) number. The HOT interlinks phenotypic, phylogenetic, genomic, clinical and bibliographic information for each taxon. A BLAST search tool is provided to match user 16S rRNA gene sequences to a curated, full length, 16S rRNA gene reference data set. For genomic analysis, HOMD provides comprehensive set of analysis tools and maintains frequently updated annotations for all the human oral microbial genomes that have been sequenced and publicly released. Oral bacterial genome sequences, determined as part of the Human Microbiome Project, are being added to the HOMD as they become available. We provide HOMD as a conceptual model for the presentation of microbiome data for other human body sites
Neisseria oralis sp. nov., isolated from healthy gingival plaque and clinical samples
A polyphasic analysis was undertaken of seven independent isolates of Gram-negative cocci collected from pathological clinical samples from New York, Louisiana, Florida and Illinois and healthy subgingival plaque from a patient in Virginia, USA. The 16S rRNA gene sequence similarity among these isolates was 99.7–100 %, and the closest species with a validly published name was Neisseria lactamica (96.9 % similarity to the type strain). DNA–DNA hybridization confirmed that these isolates are of the same species and are distinct from their nearest phylogenetic neighbour, N. lactamica. Phylogenetic analysis of 16S and 23S rRNA gene sequences indicated that the novel species belongs in the genus Neisseria. The predominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C18 : 1ω7c. The cellular fatty acid profile, together with other phenotypic characters, further supports the inclusion of the novel species in the genus Neisseria. The name Neisseria oralis sp. nov. (type strain 6332T = DSM 25276T = LMG 26725T) is proposed
Emotional persistence in online chatting communities
How do users behave in online chatrooms, where they instantaneously read and
write posts? We analyzed about 2.5 million posts covering various topics in
Internet relay channels, and found that user activity patterns follow known
power-law and stretched exponential distributions, indicating that online chat
activity is not different from other forms of communication. Analysing the
emotional expressions (positive, negative, neutral) of users, we revealed a
remarkable persistence both for individual users and channels. I.e. despite
their anonymity, users tend to follow social norms in repeated interactions in
online chats, which results in a specific emotional "tone" of the channels. We
provide an agent-based model of emotional interaction, which recovers
qualitatively both the activity patterns in chatrooms and the emotional
persistence of users and channels. While our assumptions about agent's
emotional expressions are rooted in psychology, the model allows to test
different hypothesis regarding their emotional impact in online communication.Comment: 34 pages, 4 main and 12 supplementary figure
Efficient and robust RNA-seq process for cultured bacteria and complex community transcriptomes
We have developed a process for transcriptome analysis of bacterial communities that accommodates both intact and fragmented starting RNA and combines efficient rRNA removal with strand-specific RNA-seq. We applied this approach to an RNA mixture derived from three diverse cultured bacterial species and to RNA isolated from clinical stool samples. The resulting expression profiles were highly reproducible, enriched up to 40-fold for non-rRNA transcripts, and correlated well with profiles representing undepleted total RNA
Log or Linear? Distinct Intuitions of the Number Scale in Western and Amazonian Indigene Cultures
Towards Real-Time Head Pose Estimation: Exploring Parameter-Reduced Residual Networks on In-the-wild Datasets
Head poses are a key component of human bodily communication and thus a
decisive element of human-computer interaction. Real-time head pose estimation
is crucial in the context of human-robot interaction or driver assistance
systems. The most promising approaches for head pose estimation are based on
Convolutional Neural Networks (CNNs). However, CNN models are often too complex
to achieve real-time performance. To face this challenge, we explore a popular
subgroup of CNNs, the Residual Networks (ResNets) and modify them in order to
reduce their number of parameters. The ResNets are modifed for different image
sizes including low-resolution images and combined with a varying number of
layers. They are trained on in-the-wild datasets to ensure real-world
applicability. As a result, we demonstrate that the performance of the ResNets
can be maintained while reducing the number of parameters. The modified ResNets
achieve state-of-the-art accuracy and provide fast inference for real-time
applicability.Comment: 32nd International Conference on Industrial, Engineering & Other
Applications of Applied Intelligent Systems (IEA/AIE 2019
Los ortogneises peralcalinos del borde meridional de la Unidad Malpica-Tuy: caracteres geolĂłgicos, mineralĂłgicos, geoquĂmicos y mineralizaciones de Y-Nb-Zr-TR asociadas
This paper summarizes the main tectonic, mineralogical, petrological and geochemical features of the three peralkaline complexes located in the southern end of the Malpica-Tuy Unit, in Galicia (NW Spain). The Porriño and La GuĂa complexes occur in metasedimentary rocks, mainly graywackes, of the Iberian Massif, while the Piñeiro complex is hosted by a pre-Variscun biotite granite. New data concerning the chemical composition and boundaries of the various facies which form the Porriño complex are given here. This data allow to define up to eight petrological facies and reinterprete the origin of these peralkaline bodies. The content and distribution of the major, trace and RE elements in the three complexes are the result of a magmatic differentiation process which gave place to a progressive enrichmente in SiO2 and a corresponding continuous decrease in Al2O3, Fe2O3, MgO, TiO2 and P2O5. In the Porriño complex, this geochemical trend towards more evolved rocks is consistent with field observations which show an evolution in time from the earlier biotite-hornblende to the late riebec kite, aegyrine-riebeckite, and biotite facies. Likewise, the REE content is highest in the latest radioactive biotite orthogneiss in which some mineralogically complex Y-NbZr- REE ores have been found. From the genetic point of view, the geochemical and field data show that the orthogneisses forming these peralkaline complexes fall in the field of intraplate granitoides (WPG) and correspond to A-type granites originated by melting of an anhydrous continental crust. Later on, the igneous rocks were folded and overthrust on the Precambrian-Lower Cambrian basement during the Variscan orogeny.Se resumen en este trabajo las principales caracterĂsticas tectĂłnicas, mineralĂłgicas, petrolĂłgicas y geoquĂmicas de tres complejos peralcalinos situados en el extremo meridional de la Unidad Malpica-Tuy, en Galicia (NO de España). Los complejos de Porriño y La GuĂa están encajados en rocas metasedimentarias, principalmente grauvacas, del Macizo IbĂ©rico, mientras que el complejo de Porriño se encuentra en un granito biotĂtico pre-Varisco. Se incluyen aquĂ nuevos datos referentes a la composiciĂłn quĂmica y a los lĂmites de las diferentes facies que constituyen el complejo de Porriño. Estos datos permiten definir hasta ocho facies petrolĂłgicas y reinterpretar el origen de estos cuerpos peralcalinos. El contenido y distribuciĂłn de los elementos mayores, en trazas y de las TR es el resultado, en los tres complejos, de un proceso de diferenciaciĂłn magmática que dio lugar al progresivo enriquecimiento en SiO2, y al correspondiente empobrecimiento en Al2O3, Fe2O3, MgO, TiO2 y P2O5, de las sucesivas facies. En el complejo de Porriño, esta tendencia geoquĂmica hacia rocas más evolucionadas está de acuerdo con las observaciones realizadas sobre el terreno, las cuales muestran una evoluciĂłn en el tiempo desde la facies inicial con biotita y hornblenda a las más tardĂas con riebeckita, egirina-riebeckita, y biotita. Igualmente, el mayor contenido en TR corresponde al ortogneis biotĂtico tardĂo, en el que se encuentra un yacimiento, mineralĂłgicamente muy complejo, de Y-NbZr- TR. Desde el punto de vista genĂ©tico, los datos de campo y los análisis geoquĂmicos indican que los ortogneises que forman estos complejos peralcalinos se proyectan en el campo de los granitos intraplaca (WPG) y derivan de granitos de tipo A originados por fusiĂłn de una corteza continental anhidra. Más tarde, estas rocas Ăgneas fueron plegadas y cabalgadas sobre un basamento de edad Precámbrico-Cámbrico Inferior durante la orogenia varisca
Neisseria oralis sp. nov., isolated from healthy gingival plaque and clinical samples
A polyphasic analysis was undertaken of seven independent isolates of Gram-negative cocci collected from pathological clinical samples from New York, Louisiana, Florida and Illinois and healthy subgingival plaque from a patient in Virginia, USA. The 16S rRNA gene sequence similarity among these isolates was 99.7–100 %, and the closest species with a validly published name was Neisseria lactamica (96.9 % similarity to the type strain). DNA–DNA hybridization confirmed that these isolates are of the same species and are distinct from their nearest phylogenetic neighbour, N. lactamica. Phylogenetic analysis of 16S and 23S rRNA gene sequences indicated that the novel species belongs in the genus Neisseria. The predominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C18 : 1ω7c. The cellular fatty acid profile, together with other phenotypic characters, further supports the inclusion of the novel species in the genus Neisseria. The name Neisseria oralis sp. nov. (type strain 6332T = DSM 25276T = LMG 26725T) is proposed
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