1,022 research outputs found
A logic approach for exceptions and anomalies in association rules
Association rules have been used for obtaining information hidden in a
database. Recent researches have pointed out that simple associations are
insu cient for representing the diverse kinds of knowledge collected in a
database. The use of exceptions and anomalies deal with a di erent type
of knowledge sometimes more useful than simple associations. Moreover ex-
ceptions and anomalies provide a more comprehensive understanding of the
information provided by a database.
This work intends to go deeper in the logic model studied in [5]. In the
model, association rules can be viewed as general relations between two or
more attributes quanti ed by means of a convenient quanti er. Using this
formulation we establish the true semantics of the distinct kinds of knowledge
we can nd in the database hidden in the four folds of the contingency table.
The model is also useful for providing some measures for assessing the validity
of those kinds of rulesPeer Reviewe
Functionality of In vitro Reconstituted Group II Intron RmInt1-Derived Ribonucleoprotein Particles
The functional unit of mobile group II introns is a ribonucleoprotein particle (RNP) consisting of the intron-encoded protein (IEP) and the excised intron RNA. The IEP has reverse transcriptase activity but also promotes RNA splicing, and the RNA-protein complex triggers site-specific DNA insertion by reverse splicing, in a process called retrohoming. In vitro reconstituted ribonucleoprotein complexes from the Lactococcus lactis group II intron Ll.LtrB, which produce a double strand break, have recently been studied as a means of developing group II intron-based gene targeting methods for higher organisms. The Sinorhizobium meliloti group II intron RmInt1 is an efficient mobile retroelement, the dispersal of which appears to be linked to transient single-stranded DNA during replication. The RmInt1IEP lacks the endonuclease domain (En) and cannot cut the bottom strand to generate the 3′ end to initiate reverse transcription. We used an Escherichia coli expression system to produce soluble and active RmInt1 IEP and reconstituted RNPs with purified components in vitro. The RNPs generated were functional and reverse-spliced into a single-stranded DNA target. This work constitutes the starting point for the use of group II introns lacking DNA endonuclease domain-derived RNPs for highly specific gene targeting methods.This work was supported by research grant BIO2014-51953-P of the Plan Nacional de I+D+i, Biotechnology program from the Spanish Ministerio de EconomÃa y Competitividad including ERDF (European Regional Development Funds).Peer reviewedPeer Reviewe
Alumina-zirconia coatings obtained by suspension plasma spraying from highly concentrated aqueous suspensions
Suspension plasma spraying (SPS) deposition represents an innovative technique to produce coatings that exhibit improved properties. However, the key to obtain coatings with superior functional properties relies on the investigation of the suspensions as starting materials. For this reason, the present work deals with the suspension preparation for SPS process and its influence on the resulting coatings.
Laboratory-prepared 60/40 wt% alumina-zirconia suspensions were concentrated to avoid energy loss and were then successfully deposited by SPS technique. The liquid used was water instead of ethanol due to economical, environmental and safety reasons. The preparation of the suspension plays an important role in SPS process since stable and well-dispersed water suspensions are difficult to obtain. For this reason, colloidal behaviour characterisation of the starting particles as well as rheological optimisation of the feedstock suspensions were addressed in this research.
Suspensions with different solid loadings (up to 30 vol.% or 72 wt%) were deposited using several spraying distances. All coatings displayed a bimodal microstructure consisting in partially melted zones surrounded by a fully melted matrix. α-Al2O3 and t’-ZrO2 constituted the main crystalline phases, but differences in the microstructure and properties of the coatings were observed. From these results, some relations between starting suspension and spraying parameters with coating characteristics were found. Thus the optimal spraying distance becomes shorter when the suspension solid loading increases.This work has been supported by the Spanish Ministry of Economy and Competitiveness, MINECO, (project MAT2015-67586-C3-R). M.D. Salvador thanks to CAPES – Programa Ciências sem Fronteiras (Brazil) for the concession of a PVE project Nº A086/2013. A. Borrell acknowledges the MINECO for her Juan de la Cierva-Incorporación contract (IJCI-2014-19839) and the Program to Support Research and Development (PAID-00-15) of the Universitat Politècnica de València
Influence of track modelling in modal parameters of railway bridges composed by single-track adjacent decks
[EN] A significant number of railway bridges composed by simply-supported (SS) spans are present in existing railway lines. Special attention must be paid to short to medium span length structures, as they are prone to experience high vertical acceleration levels at the deck, due to their low weight and damping, compromising the travelling comfort and the structural integrity. The accurate prediction of the dynamic response of these bridges is a complex issue since it is affected by uncertain factors such as structural damping and complex interaction mechanisms such as vehicle-bridge, soil-structure or track-bridge interaction. Concerning track-bridge interaction, experimental evidences of a dynamic coupling exerted by the ballasted track between subsequent SS spans and also between structurally independent single-track twin adjacent decks have been reported in the literature [1, 2]. Nevertheless, this phenomenon is frequently disregarded due to the computational cost of models including the track and due to the uncertainties in the mechanical parameters that define the track system. The present work contributes to the study of the coupling effect exerted by the ballasted track between independent structures in railway bridges. With this purpose two 3D finite element (FE) track-bridge interaction models are implemented. The former includes a continuous representation of the track components meshing the sleepers, ballast and sub-ballast with solid FE. In the latter, the track is represented as a 2D discrete three-layer model where the mass, stiffness and damping of the components are concentrated at the sleepers locations. The numerical models are updated with experimental measurements performed on an existing railway bridge in a view to evaluate (i) the influence of the track continuity on the bridge modal parameters and on the train-induced vibrations; (ii) the adequacy of the implemented numerical models and (iii) the importance of the track-bridge interaction for an accurate prediction of the vertical acceleration levels under operating conditions.The authors would like to acknowledge the financial support provided by the Spanish Ministry of Science and Innovation under research project PID2019-109622RB; FEDER AndalucÃa 2014-2020 Operational Program for project US-126491; Generalitat Valenciana and Universitat Jaume I under research projects AICO2019/175 and UJI/A2008/06; and the Andalusian Scientific Computing Centre (CICA).Sánchez Quesada, J.; Moliner, E.; Romero, A.; GalvÃn, P.; MartÃnez-Rodrigo, M. (2022). Influence of track modelling in modal parameters of railway bridges composed by single-track adjacent decks. En Proceedings of the YIC 2021 - VI ECCOMAS Young Investigators Conference. Editorial Universitat Politècnica de València. 278-287. https://doi.org/10.4995/YIC2021.2021.12283OCS27828
Antibacterial activity of bovine milk lactoferrin on the emerging foodborne pathogen Cronobacter sakazakii: Effect of media and heat treatment
Cronobacter sakazakii is a pathogen transmitted by food, with high osmotic resistance and tolerance to desiccation, which affects mainly to newborns, infants and immunocompromised adults. C. sakazakii infection in infants has been associated with consumption of powdered milk. The purpose of this study was to evaluate the antibacterial activity of native and iron-saturated bovine lactoferrin (bLF) (from 0.5 to 5 mg/ml) on non-desiccated and desiccated C. sakazakii (104 CFU/ml) in different media (phosphate buffer, bovine skim milk and whey). In general, native bLF was the only effective form that inhibited growth of C. sakazakii in all media, its activity increasing with concentration and time of incubation. These results suggest that the antibacterial effect of bLF on C. sakazakii is mainly due to iron sequestration. However, iron-saturated bLF showed some effect by reducing the viability of C. sakazakii in whey. There has not been observed an increased sensitivity of desiccated bacteria to native bLF in phosphate buffer. However, although the antibacterial activity of native bLF against non-desiccated C. sakazakii was drastically reduced in milk or whey compared to phosphate buffer, there was a certain activity when it was assayed against desiccated cells in those media. The effect of some heat treatments on the antibacterial activity of native bLF was evaluated and only those of 72 °C for 15 s, 85 °C for 15 s, and 63 °C for 30 min maintained its whole activity
Prediction of adult conformation traits from shape characteristics of Pura Raza Español foals.
Nº ArtÃculo 104701Horse conformation has been proposed as an indirect indicator of performance, since their genetic correlations
are often positive and high. In Pura Raza Espa ̃nol (PRE) horses, the selection of conformation traits more related
to functionality and performance allows a pre-selection of animals and contributes towards saving costs and
increasing the genetic progress. The aim of this paper is to evaluate the predictability of 16 conformation traits
(14 body measurements and 2 linear conformation traits) in adult PRE horses, focusing on the conformation
traits of foals. The dataset included 155,716 records (82,408 young and 73,308 adult horses) with conformation
traits from 142,244 different horses, aged between 1-36 years old. Animals between 1-3 years old were included
in the ‘young’ group and older animals in the ‘adult’ group. A univariate General Linear Model procedure fol-
lowed by a Tukey-post-hoc test were used to assess the statistical significance of non-genetic effects. Heritability
values were estimated univariately. The fitted models included breeder, age and inbreeding (F) as covariates, and
sex and coat colour as fixed effects. Coat colour and F were significant for 75% and 87.5% of the traits analysed,
respectively; and the other effects analysed were significant for all the conformation traits. Heritability values
ranged between 0.178±0.0063 and 0.795±0.0098 in young horses, and between 0.273±0.0038 and
0.894±0.0007 in adult horses. The genetic correlations of the conformation traits between young and adult
horses were above 0.75 for 93.75% of the conformation traits analysed, which confirms the efficiency of pre-
selection in young horses based on conformation features to predict their adult performance
Sutureless colic anastomoses with cyanoacrylates
BACKGROUNO ANO AIMS. The present research Project has been made mainly with the idea of comparing the tensile strength values and histological answers of threetypes of colon anatomises: sutured with silk and sutureless anastomoses with 2-octyl-cyanocrylate and N-butyl-2-cyanoacrylate.
Methods. 112 Wistar rats distributed into three groups of 35 animals and a last control group of 7 have been used for this. Group 1: silk, group 2:2-octyl-cyanocrylate, group 3: N-butyl-2-cyanoacrylate,group 4: Control group_. The following surgical interventions were practiced on them:A cross section of the colon,followed by: group 1: an end-to-end discontinuous suture anastomoses with Silk; group 2: sutureless anastomoses with 2-octyl-cyanocrylate;group 3:sutureless anastomoses With N-butyl-2-cyanoar1ylate. On the 10th, 20th, 30th, 40th and 50th days we proceeded to measure the anastomoses tensile strength value for each series.In the same period of time we carried out the following anatomic-pathological determinations: a) sharp inflammation; b) oedema; c) non-specif chronic inflammatory infiltrate; d) granulomatous inflammatory infiltrate to foreign e) fibrosis.
Results.The results obtained indicate a greater anastomeses tensile strength for group 2 and 3. The anatomic-pathological values show a better response to anastomoses with adhesive than with conventional sutures.
CONCLUSIONS. All these experimental results lead us to conclude that the cyanocrilates used to carry out sutureless anastomoses may be an n alternative to the handmade conventional anastomoses. Moreover they are easy to be implemented
Tool wear study in edge trimming on basalt fibre reinforced plastics
[EN] In machining of reinforced fibre composite parts, abrasive fibres and material heterogeneity produce poor surface finish, delamination and tool wear. In this research, basalt fibre reinforced plastic is machined with edge trimming in order to study tool wear, using a tool holder of diameter 25 mm, with two exchangeable uncoated carbide cutting inserts. Cutting conditions (cutting speed, feed per tooth and depth) and material characteristics (fibre volume fraction and fibre orientation) are evaluated to know their influence in the flank wear (Vb) of the tool. An analysis of variance (ANOVA) was performed to study flank wear and material removal rate, and a generalized linear model (GLM) was developed. More influence variables in the flank wear are the machining conditions, being the tool life suitable for this machining and material.This work was funded by the Research Project DPI2013-44903-R-AR of the MINER.Navarro-Mas, M.; Meseguer, MD.; Sánchez Galdón, AI.; Gutiérrez, SC. (2017). Tool wear study in edge trimming on basalt fibre reinforced plastics. Procedia Manufacturing. 13:259-266. doi:10.1016/j.promfg.2017.09.067S2592661
Antispasmodic effects and action mechanism of essential oil of Chrysactinia mexicana A. Gray on rabbit ileum
The Chrysactinia mexicana A. Gray (C. mexicana) plant is used in folk medicine to treat fever and rheumatism; it is used as a diuretic, antispasmodic; and it is used for its aphrodisiac properties. This study investigates the effects of the essential oil of C. mexicana (EOCM) on the contractility of rabbit ileum and the mechanisms of action involved. Muscle contractility studies in vitro in an organ bath to evaluate the response to EOCM were performed in the rabbit ileum. EOCM (1–100 µg·mL-1) reduced the amplitude and area under the curve of spontaneous contractions of the ileum. The contractions induced by carbachol 1 µM, potassium chloride (KCl) 60 mM or Bay K8644 1 µM were reduced by EOCM (30 µg·mL-1). Apamin 1 µM and charybdotoxin 0.01 µM decreased the inhibition induced by EOCM. The d-cAMP 1 µM decreased the inhibition induced by EOCM. l-NNA 10 µM, Rp-8-Br-PET-cGMPS 1 µM, d, l-propargylglycine 2 mM, or aminooxyacetic acid hemihydrochloride 2 mM did not modify the EOCM effect. In conclusion, EOCM induces an antispasmodic effect and could be used in the treatment of intestinal spasms or diarrhea processes. This effect would be mediated by Ca2+, Ca2+-activated K+ channels and cAMP
Peroxidase expression in a cereal cyst nematode (Heterodera avenae) resistant hexaploid wheat line.
The incompatible interaction between plant and pathogen is often determined by the hypersensitive reaction (HR). This response is associated with accumulation of reactive oxygen species (ROS), which results in adverse growth conditions for pathogens. Two major mechanisms involving either NADPH oxidases or peroxidases have been proposed for generation of ROS. Peroxidases (PER, EC 1.11.1.7), present in all land plants, are members of a large multigenic family with high number of isoforms involved in a broad range of physiological processes. PER genes, which are expressed in nematode feeding sites, have been identified in several plant species (Zacheo et al. 1997). A strong correlation between HR and PER activities at four and seven days post nematode infection, was detected in roots of wheat lines carrying Cre2, Cre5 (from Ae. ventricosa) or Cre7 (from Ae. triuncialis) Heterodera avenae resistance genes (Andrés et al. 2001; Montes et al. 2003, 2004). We have studied changes in root of peroxidase mRNAs levels after infection by H. avenae of a wheat/Ae. ven¬tricosa introgression line (H-93-8) carrying Cre2 (Delibes et al. 1993). We also report and classify the predicted protein sequences derived from complete peroxidase transcripts
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