190 research outputs found
Detection of root canals in historical population from Radom (Poland)
Background: The aim of this study was to analyse the number of root canals in maxillary first premolars, first molars and mandibular first molar teeth from an 18th to 19th century Radom (Poland) population, and then assess whether the diversity of root canals has fluctuated for about two hundred years.
Materials and methods: A total of 139 human permanent teeth were analysed by cone beam computed tomography in three projections. The types of root canal systems were classified in each tooth root separately.
Results: In one-rooted maxillary premolars, two canals occurred most often (53%). In two-rooted majority buccal (91%) and every palatal roots there is one canal. All three-rooted maxillary premolars have one root canal. In two-rooted first maxillary molars, fused roots have two canals. All mesiobuccal roots presented type 2-1 canal configurations. In three-rooted maxillary first molars in the mesiobuccal roots the most common root canal type is 2-1 (72%). A second mesiobuccal canal occurred in 86%. The distobuccal and palatal roots presented one canal in all cases. First mandibular molars occurred in two-rooted form in 98%. In mesial roots, two root canals predominated (59%). Most distal root (66%) had one canal. In three-rooted teeth one root canal was the most frequent finding.
Conclusions: Knowledge about the variation in root canals is important in studies of past populations. This evidence may be important in relation to assessing the variability of human populations. The analysis carried out show the cohesion between the historical population of Radom and other groups from modern Poland
Charakteristiken einer netzgestützten wissenschaftlichen Kommunikation und ihre Umsetzung in Infrastruktur und Publikationsformen
Neue Formen der wissenschaftlichen Kommunikation basieren auf Fortschritten in den Informations- und Kommunikationstechnologien. Das dadurch mögliche kollaborative wissenschaftliche Arbeiten liefert Ergebnisse, die in vielfältigen Formaten, als Text, Simulationsdaten oder multimediale Elemente vorliegen. Daraus ergeben sich besondere Anforderungen an Publikations- und Kommunikatonsinfrastrukturen, wie Interoperabilität, Repräsentation, Verteilung und Archivierung derartiger komplexer digitaler Objekte. Mit der Initiative Digital Peer Publishing existiert eine Infrastruktur für das Publizieren in elektronischen Zeitschriften. Dieses Publikationsformat erlaubt neben einem schnellen Wissenstransfer eine umfassende Repräsentation wissenschaftlicher Ergebnisse. Das Journal of Virtual Reality and Broadcasting als Teil dieser Initiative zeigt am Beispiel des elektronischen Publikationsprozesses den Stand der Wissensvernetzung in seiner Community, sowie aktuelle Entwicklungen um die Erweiterung innovativer Funktionen
Variant phasing and haplotypic expression from long-read sequencing in maize
Haplotype phasing maize genetic variants is important for genome interpretation, population genetic analysis and functional analysis of allelic activity. We performed an isoform-level phasing study using two maize inbred lines and their reciprocal crosses, based on single-molecule, full-length cDNA sequencing. To phase and analyze transcripts between hybrids and parents, we developed IsoPhase. Using this tool, we validated the majority of SNPs called against matching short-read data from embryo, endosperm and root tissues, and identified allele-specific, gene-level and isoform-level differential expression between the inbred parental lines and hybrid offspring. After phasing 6907 genes in the reciprocal hybrids, we annotated the SNPs and identified large-effect genes. In addition, we identified parent-of-origin isoforms, distinct novel isoforms in maize parent and hybrid lines, and imprinted genes from different tissues. Finally, we characterized variation in cis- and trans-regulatory effects. Our study provides measures of haplotypic expression that could increase accuracy in studies of allelic expression
Mathematical formalisms to represent knowledge concerning the production process of austempered ductile iron
The aim of this study is to develop computer tools for calculation of the Fe - Fe3C phase equilibrium diagram. The phase equilibrium diagram is of fundamental importance in materials science and heat treatment processes of ferrous alloys. It enables prediction of carbon steel microstructure in the annealed condition, and facilitates selection of proper temperature for the heat treatment process. Choosing the right values of the heat treatment process parameters is essential in the production of Austempered Ductile Iron (ADI)
The genome of the jellyfish Aurelia and the evolution of animal complexity
We present the genome of the moon jellyfish Aurelia, a genome from a cnidarian with a medusa life stage. Our analyses suggest that gene gain and loss in Aurelia is comparable to what has been found in its morphologically simpler relatives—the anthozoan corals and sea anemones. RNA sequencing analysis does not support the hypothesis that taxonomically restricted (orphan) genes play an oversized role in the development of the medusa stage. Instead, genes broadly conserved across animals and eukaryotes play comparable roles throughout the life cycle. All life stages of Aurelia are significantly enriched in the expression of genes that are hypothesized to interact in protein networks found in bilaterian animals. Collectively, our results suggest that increased life cycle complexity in Aurelia does not correlate with an increased number of genes. This leads to two possible evolutionary scenarios: either medusozoans evolved their complex medusa life stage (with concomitant shifts into new ecological niches) primarily by re-working genetic pathways already present in the last common ancestor of cnidarians, or the earliest cnidarians had a medusa life stage, which was subsequently lost in the anthozoans. While we favour the earlier hypothesis, the latter is consistent with growing evidence that many of the earliest animals were more physically complex than previously hypothesized
Understanding the errors of SHAPE-directed RNA structure modeling
Single-nucleotide-resolution chemical mapping for structured RNA is being
rapidly advanced by new chemistries, faster readouts, and coupling to
computational algorithms. Recent tests have shown that selective 2'-hydroxyl
acylation by primer extension (SHAPE) can give near-zero error rates (0-2%) in
modeling the helices of RNA secondary structure. Here, we benchmark the method
using six molecules for which crystallographic data are available: tRNA(phe)
and 5S rRNA from Escherichia coli, the P4-P6 domain of the Tetrahymena group I
ribozyme, and ligand-bound domains from riboswitches for adenine, cyclic
di-GMP, and glycine. SHAPE-directed modeling of these highly structured RNAs
gave an overall false negative rate (FNR) of 17% and a false discovery rate
(FDR) of 21%, with at least one helix prediction error in five of the six
cases. Extensive variations of data processing, normalization, and modeling
parameters did not significantly mitigate modeling errors. Only one varation,
filtering out data collected with deoxyinosine triphosphate during primer
extension, gave a modest improvement (FNR = 12%, and FDR = 14%). The residual
structure modeling errors are explained by the insufficient information content
of these RNAs' SHAPE data, as evaluated by a nonparametric bootstrapping
analysis. Beyond these benchmark cases, bootstrapping suggests a low level of
confidence (<50%) in the majority of helices in a previously proposed
SHAPE-directed model for the HIV-1 RNA genome. Thus, SHAPE-directed RNA
modeling is not always unambiguous, and helix-by-helix confidence estimates, as
described herein, may be critical for interpreting results from this powerful
methodology.Comment: Biochemistry, Article ASAP (Aug. 15, 2011
POLISH TOWNS AND THE CHANGES IN THEIR AREAS AND POPULATION DENSITIES
DOI: 10.2478
Available on-line at:
http://www.bulletinofgeography.umk.pl
http://versita.com/bgssThis article presents the spatial and population density changes in Polish towns in the years 1960–2003. The assumed time frame allowed identifying area changes for a complete set of towns in different socio-economic conditions: the period of intense industrialisation, the economic crisis of the 1980s, the period of economic transition and finally in the years of a market economy. The investigation revealed that the trend
shown by changes and the size of a town as measured by the number of its population are distinctly interrelated. It also demonstrated a much stronger dynamics of changes in the first subperiod, i.e. years 1960–1985, followed by a phase of relative stabilization (compared with the previous period) after the year 1980 (mainly of the spatial changes). Moreover, change intensity and change trends observed for the urban areas and population densities vary considerably in terms of space
MSD1 regulates pedicellate spikelet fertility in sorghum through the jasmonic acid pathway
Grain number per panicle (GNP) is a major determinant of grain yield in cereals. However, the mechanisms that regulate GNP remain unclear. To address this issue, we isolate a series of sorghum [Sorghum bicolor (L.) Moench] multiseeded (msd) mutants that can double GNP by increasing panicle size and altering floral development so that all spikelets are fertile and set grain. Through bulk segregant analysis by next-generation sequencing, we identify MSD1 as a TCP (Teosinte branched/Cycloidea/PCF) transcription factor. Whole-genome expression profiling reveals that jasmonic acid (JA) biosynthetic enzymes are transiently activated in pedicellate spikelets. Young msd1 panicles have 50% less JA than wild-type (WT) panicles, and application of exogenous JA can rescue the msd1 phenotype. Our results reveal a new mechanism for increasing GNP, with the potential to boost grain yield, and provide insight into the regulation of plant inflorescence architecture and development
The genome of the jellyfish Aurelia and the evolution of animal complexity
We present the genome of the moon jellyfish Aurelia, a genome from a cnidarian with a medusa life stage. Our analyses suggest that gene gain and loss in Aurelia is comparable to what has been found in its morphologically simpler relatives—the anthozoan corals and sea anemones. RNA sequencing analysis does not support the hypothesis that taxonomically restricted (orphan) genes play an oversized role in the development of the medusa stage. Instead, genes broadly conserved across animals and eukaryotes play comparable roles throughout the life cycle. All life stages of Aurelia are significantly enriched in the expression of genes that are hypothesized to interact in protein networks found in bilaterian animals. Collectively, our results suggest that increased life cycle complexity in Aurelia does not correlate with an increased number of genes. This leads to two possible evolutionary scenarios: either medusozoans evolved their complex medusa life stage (with concomitant shifts into new ecological niches) primarily by re-working genetic pathways already present in the last common ancestor of cnidarians, or the earliest cnidarians had a medusa life stage, which was subsequently lost in the anthozoans. While we favour the earlier hypothesis, the latter is consistent with growing evidence that many of the earliest animals were more physically complex than previously hypothesized
Management, Analyses, and Distribution of the MaizeCODE Data on the Cloud
MaizeCODE is a project aimed at identifying and analyzing functional elements in the maize genome. In its initial phase, MaizeCODE assayed up to five tissues from four maize strains (B73, NC350, W22, TIL11) by RNA-Seq, Chip-Seq, RAMPAGE, and small RNA sequencing. To facilitate reproducible science and provide both human and machine access to the MaizeCODE data, we enhanced SciApps, a cloud-based portal, for analysis and distribution of both raw data and analysis results. Based on the SciApps workflow platform, we generated new components to support the complete cycle of MaizeCODE data management. These include publicly accessible scientific workflows for the reproducible and shareable analysis of various functional data, a RESTful API for batch processing and distribution of data and metadata, a searchable data page that lists each MaizeCODE experiment as a reproducible workflow, and integrated JBrowse genome browser tracks linked with workflows and metadata. The SciApps portal is a flexible platform that allows the integration of new analysis tools, workflows, and genomic data from multiple projects. Through metadata and a ready-to-compute cloud-based platform, the portal experience improves access to the MaizeCODE data and facilitates its analysis
- …