Evolución y distribución sectorial de las fusiones de empresas españolas

Es evidente que los procedimientos de fusión han sido empleados por las empresas españolas como estrategias para afrontar los retos competitivos en sus diferentes entornos económicos y, aunque han sido estudiados sus causas y resultados; el impacto global en el contexto de la economía española y su utilización real no han sido suficientemente investigados, sobre todo, debido a la falta de bases estadísticas apropiadas. En este trabajo, partiendo de la información de las últimas dos décadas, se analiza cuál ha sido su empleo efectivo, características y evolución, así como aquellos sectores más intensamente afectados. Para obtener una base que permita vislumbrar las posibles tendencias futuras de estas [email protected]

Band-pass filtering of the time sequences of spectral parameters for robust wireless speech recognition

In this paper we address the problem of automatic speech recognition when wireless speech communication systems are involved. In this context, three main sources of distortion should be considered: acoustic environment, speech coding and transmission errors. Whilst the first one has already received a lot of attention, the last two deserve further investigation in our opinion. We have found out that band-pass filtering of the recognition features improves ASR performance when distortions due to these particular communication systems are present. Furthermore, we have evaluated two alternative configurations at different bit error rates (BER) typical of these channels: band-pass filtering the LP-MFCC parameters or a modification of the RASTA-PLP using a sharper low-pass section perform consistently better than LP-MFCC and RASTA-PLP, respectively.Publicad

Short-term effect of zoledronic acid upon fracture resistance of the mandibular condyle and femoral head in an animal model

Objective: The aim of this study was to compare the effects in terms of resistance to fracture of the mandibular condyle and femoral head following different doses of zoledronic acid in an animal model. Study design: A total of 80 adult male Sprague-Dawley rats were included in a prospective randomized study. The animals were randomly divided into four groups of 20 rats each. Group 1 (control) received sterile saline solution, while groups 2, 3 and 4 received a accumulated dose of 0.2 mg, 0.4 mg and 0.6 mg of zoledronic acid, respectively. The animals were sacrificed 28 days after the last dose, and the right hemimandible and the right femur were removed. The fracture strength was measured (in Newtons) with a universal test machine using a 1 kN load connected to a metal rod with one end angled at 30 degrees. The cross-head speed was 1 mm/min. Later, the specimens were observed under a scanning electron microscope with backscattered electron imaging (SEM- BSE). At last, chemical analysis and elemental mapping of the mineral bone composition were generated using a microanalytical system based on energy-dispersive and X-ray spectrometry (EDX). Results: A total of 160 fracture tests were performed. The fracture resistance increased in mandible and femur with a higher accumulated dose of zoledronic acid. Statistically significant differences were recorded versus the controls with all the studies groups. The chemical analysis in mandible showed a significantly increased of calcium and phosphorous to compare the control with all of the study groups; however, in femur no statistically significant differences between the four study groups were observed. Conclusions: The administration of bisphosphonates increases the fracture resistance in mandible and femur

Effect of posterior gingival smile on the perception of smile esthetics

Objectives: To evaluate and compare the influence of posterior gummy smile on the perception of smile esthetics by orthodontists, general-dentists and laypersons. Study Design: A frontal photograph of a smile with normal gum exposure was chosen and manipulated digitally using Adobe Photoshop C3 to generate three further images with posterior gum exposure of 4, 6 and 8mm. These four images were assessed by the three evaluator groups: orthodontists (n=40), general-dentists (n=40) and laypersons (n=40). Both orthodontists and dentists had at least ten years professional experience and laypersons were aged between 40-50 years. The proportion of men to women was 20:20 in each group. Evaluators awarded a score to the smile esthetics of each image: 1=acceptable, 2=moderately acceptable, 3=unacceptable. Afterwards, each evaluator placed the four images in order of esthetic preference. Results: No significant differences (p>0.05) were detected between the three evaluator groups for the photo without posterior gummy smile. The perception of smile esthetics for a the 4mm posterior gummy smile (median for orthodontists=2, general-dentists= 1, laypersons=1), the 6mm (median for orthodontists=2, general-dentists=1, laypersons=1) and the 8mm (median for orthodontists=3, general-dentists=2, laypersons=2) was significantly different between orthodontists and the other two evaluator groups (p<0.0017). The three evaluator groups coincided in placing the image with the 6mm gum exposure in first place in order of esthetic preference. Conclusions: Posterior gummy smile influences the perception of smile esthetics more negatively among orthodontists than the rest of the groups

A new use for self-etching resin adhesives: Cementing bone fragments

© 2010 Elsevier Ltd. This document is the Published version of a Published Work that appeared in final form in Journal of Dentistry. To access the final edited and published work see https://doi.org/10.1016/j.jdent.2010.06.002Objectives: To evaluate the bond capacities of four self-etching resin cements and the self-etching adhesives of the same manufacturer when used to cement bone fragments and compare them with a well-known N-butyl-2-cyanoacrylate bone adhesive. Methods: 125 cylindrical bone specimens from pig mandibular ramus bone were prepared using terphane burs and cemented to the corticals of 125 other specimens obtained from pig mandibular body bone using the following bond systems: Group A: Adper PLP/Relyx; group B: Optibond/Maxcem; group C: Hystoacryl; group D: AdheSE/Multilink; group E: G-Bond/G-Cem. Shear bond strength was measured 15 min after cement application using a universal testing machine. Results: Shear bond strength results: group A 2.54 ± 0.23 MPa; group B 4.83 ± 0.4 MPa; group C 2.90 ± 0.24 MPa; group D 2.10 ± 0.17 MPa; group E 4.22 ± 0.24 MPa. Values for shear bond strength were significantly greater for group B and E compared to groups A, C and D (p < 0.005, test Mann–Whitney). SEM images showed the presence of a hybrid layer similar to that formed by these bond systems when used on dentine. Conclusion: Within the limitations of an in vitro investigation, results show that self-etching resin cements together with self-etching adhesives may be used for cementing bone fragments

Influence of food-simulating liquids on bond strength of brackets bonded with a HEMA-free and HEMA-containing self-etching primer

© 2012 by The EH Angle Education and Research Foundation, Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/. This document is the Published version of a Published Work that appeared in final form in Angle Orthodontist. To access the final edited and published work see https://doi.org/10.2319/032711-216.1Objective: To evaluate the effect of food-simulating liquids on bond strengths of brackets bonded with a HEMA-free and a HEMA-containing self-etching primer. Materials and Methods: Brackets were bonded to 280 bovine incisors that were divided into two groups: (1) Adper Prompt-L-Pop (Adper PLP)/Transbond-XT and (2) Transbond Plus self-etching primer (TSEP, HEMA-free)/Transbond-XT. Each group was evaluated under different storage conditions: 24 hours in water, thermocycling (T), T/12 weeks in water, T/12 weeks in 10% ethanol, T/12 weeks in 50% ethanol, T/12 weeks in 3% acetic acid, and T/12 weeks in olive oil. Shear bond strength was measured with a universal test machine. Results: TSEP and Adper PLP showed a significantly higher bond strength at 24 hours than at T/12 weeks in 50% ethanol (P  =  .000). For Adper PLP, the bond strength at 24 hours was significantly higher than T/12 weeks in water (P  =  .000). Significant differences were not detected between the two bonding procedures for the different storage conditions (P > .05). Conclusion: Owing to its hydrophilic nature, the bond strength produced by Adper PLP (a HEMA-containing self-etching primer) decreased significantly after T/12 weeks in water. Brackets bonded with both TSEP and Adper PLP showed significantly higher bond strengths at 24 hours than at T/12 weeks in 50% ethanol, probably due to the effect of ethanol at 50% on Transbond-XT

Programa de educación para la salud dirigido a la prevención de cardiopatía isquémica en personas en edad adulto-anciana

La cardiopatía isquémica se define como la enfermedad cardíaca producida por las alteraciones fisiopatológicas secundarias a la aparición de un desequilibrio entre la demanda y el aporte de oxígeno del músculo cardíaco.Esta enfermedad es un problema de salud que produce 7,5 millones de muertes en el mundo y que puede ser controlado a partir de la modificación de estilos de vida y la disminución de factores de riesgo. Los principales factores de riesgo cardiovascular (modificables o no modificables) son la edad, el sexo, la hipertensión arterial, el tabaquismo, la diabetes mellitus, la dislipidemia y la obesidad.El papel de enfermería para el control de los factores de riesgo y seguimiento de una rutina saludable es imprescindible.ObjetivoDiseñar un programa de salud dirigido a reducir la tasa de morbimortalidad por cardiopatía isquémica mediante la prevención primaria en personas entre 50 y 70 años.MetodologíaPara la realización del trabajo se ha llevado a cabo una búsqueda bibliográfica entre los meses de febrero y mayo del año 2021 en diferentes bases de datos.DesarrolloSe va a realizar un programa de educación para la salud con 4 sesiones educativas en personas adulto-ancianas, para que tomen conciencia de la enfermedad y de la importancia de corregir factores de riesgo modificables.ConclusionesLos programas de educación para la salud destinados a la prevención cardiovascular realizan un papel imprescindible para evitar la enfermedad o su detección en fases tempranas. La prevención se aborda desde una perspectiva global, mediante la promoción de estilos de vida saludables y el control de los principales factores de riesgo.<br /

High-throughput DNA sequencing of microbiota at interproximal sites

©2020. This manuscript version is made available under the CC-BY 4.0 license http://creativecommons.org/licenses/by/4.0/ This document is the Published, version of a Published Work that appeared in final form in Journal of Oral Microbiology. To access the final edited and published work seehttps://doi.org/10.1080/20002297.2019.1687397Objective: The oral microbiota has been deeply studied by high-throughput sequencing techniques. However, although the interproximal regions have one of the highest caries rates in the oral cavity, information about the bacterial composition at those sites is scarce. Methods: In this study, we used 16S rRNA Illumina sequencing to describe the microbiota associated to interproximal regions at two time points. In addition, dental plaque samples at the vestibular and lingual surfaces from the same teeth were also analysed at the two time points. Results: Interproximal-associated microbiota was found to be similar to already described bacterial communities in other mouth niches. Streptoccocus, Veillonella, Rothia, Actinomyces, Neisseria, Haemophilus and Fusobacterium were the most abundant genera in this oral region. Statistical analyses showed that the microbiota from interproximal sites was more similar to that sampled from the vestibular surfaces than to the lingual surfaces. Interestingly, many potentially cariogenic bacteria such as Scardovia, Atopobium or Selenomonas were overrepresented in the interproximal regions in comparison with vestibular and lingual sites. Conclusion: The microbiota at interproximal regions appears to be specific and stable through time. Potentially pathogenic bacteria may increase caries development risk and gingival inflammation at those sites

Conceptos actuales de la fisiopatología de las tendinopatías. Ingeniería tisular

La tendinopatía es una lesión frecuente que se produce durante la práctica deportiva. El reparto desigual de la carga de trabajo a lo largo del tendón produce roturas heterogéneas en extensión y distribución. Estas roturas ponen en marcha procesos de reparación defectuosos que producen un tendón degenerado con alteración estructural y de la respuesta funcional al ejercicio. En este trabajo se estudian y analizan los distintos factores predisponentes, mecanismos de acción de los agentes químicos y celulares implicados en la fisiopatología de la tendinopatías. Por otra parte, se analizan los componentes básicos (soporte, células y sustancias químicas) que se usan para la ingeniería tisular. Las posibilidades actuales de uso de los componentes básicos y sus interrelaciones, y el nivel actual de desarrollo

Conceptes actuals de la fisiopatologia de les tendinopaties. Enginyeria tissular

La tendinopatia és una lesió freqüent que es produeix durant la pràctica esportiva. El repartiment desigual de la càrrega de treball al llarg del tendó produeix trencaments heterogenis en extensió i distribució. Aquests trencaments posen en marxa processos de reparació defectuosos que produeixen un tendó degenerat amb alteració estructural i de la resposta funcional a l’exercici. En aquest treball s’estudien i analitzen els diferents factors predisponents, mecanismes d’acció dels agents químics i cel·lulars implicats en la fisiopatologia de les tendinopaties. D’altra banda, s’analitzen els components bàsics (suport, cèl·lules i substàncies químiques) que es fan servir per a la ingenieria tissular. Les probabilitats actuals d’ús dels components bàsics i les seves interrelacions i el nivell actual de desenvolupament