806 research outputs found

    The M/G/1 retrial queue: an information theoretic approach

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    In this paper, we give a survey of the use of information theoretic techniques for the estimation of the main performance characteristics of the M/G/1 retrial queue. We focus on the limiting distribution of the system state, the length of a busy period and the waiting time. Numerical examples are given to illustrate the accuracy of the maximum entropy estimations when they are compared versus the classical solutions.Peer Reviewe

    Teacher-Rated Executive Functions, Gender and Relative Age: Independent and Interactive Effects on Observed Fundamental Motor Skills in Kindergarteners

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    Fundamental motor skills (FMS) of children can be affected by different variables, such as executive functions (EF), gender and relative age. However, the effects of these variables on FMS have been scarce studied, especially in early childhood, and show inconsistent results. To clarify these relationships, this study was carried out. Its aim was to analyze whether EF, gender and relative age influenced FMS in 43 Spanish kindergarteners. A multimethod and mixed methods approach was used. Kindergarteners’ teachers completed the Childhood Executive Functioning Inventory to know the children level of EF (working memory and inhibition control). Kindergarteners’ parents complimented ad hoc questionnaire reporting the children gender and birth data (to know their relative age). A Nomothetic/Punctual/Multidimensional observational design was used to observe children FMS in their habitual motor sessions at school. Two-way ANOVAs were performed to know the independent and interactive effects of working memory level (lower/higher), inhibition control level (lower/higher), gender (boys/girls) and relative age (according to the birth semester in the year) on FMS. Results showed these variables have independent and interactive effects on some FMS, but not on others. FMS influenced by these variables vary depending what independent variable(s) is/are considered. Therefore, it can be concluded that the influences of teacher-rated EF, gender and relative age on observed FMS in kindergarteners are complex and specific. Results obtained must be taken into to design and implement instructional and intervention strategies, as well as educational and sport policy changes, especially in early childhood, when FMS are more malleable

    Effectiveness of dry needling for headache: A systematic review.

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    Introducción El uso de tratamientos no farmacológicos en pacientes con cefalea, como la punción seca (PS), está asociado a una baja morbimortalidad y a un bajo coste sanitario. Algunos han demostrado utilidad en la práctica clínica. El objetivo de esta revisión fue analizar el grado de evidencia de la efectividad de la PS en la cefalea. Métodos Revisión sistemática de ensayos clínicos aleatorizados sobre cefalea y PS en las bases de datos biomédicas PubMed, Web of Science, Scopus y PEDro. Se evaluó la calidad de los estudios incluidos mediante la escala PEDro por 2 evaluadores de forma independiente. Resultados De un total de 136 estudios, se seleccionaron 8 ensayos clínicos publicados entre 1994 y 2019, incluyendo en total 577 pacientes. Dos estudios evaluaron pacientes con cefalea cervicogénica, otros 2, pacientes con cefalea tensional, y otro, pacientes con migraña. Los otros 3 estudios evaluaron pacientes con cefalea de características mixtas (tensional/migraña). La calidad de los estudios incluidos osciló entre «baja» (3/10) y «alta» (8/10). La eficacia de la PS sobre los episodios de cefalea fue similar a la de los tratamientos con los que se comparó. No obstante, obtuvo mejoras significativas respecto a variables funcionales y de sensibilidad. Conclusiones La punción seca es una técnica a considerar para el tratamiento de las cefaleas en la consulta, pudiendo utilizarse de forma rutinaria, bien de forma aislada, bien en combinación con terapias farmacológicas. Introduction Non-pharmacological treatment of patients with headache, such as dry needling (DN), is associated with less morbidity and mortality and lower costs than pharmacological treatment. Some of these techniques are useful in clinical practice. The aim of this study was to review the level of evidence for DN in patients with headache. Methods We performed a systematic review of randomised clinical trials on headache and DN on the PubMed, Web of Science, Scopus, and PEDro databases. Methodological quality was evaluated with the Spanish version of the PEDro scale by 2 independent reviewers. Results Of a total of 136 studies, we selected 8 randomised clinical trials published between 1994 and 2019, including a total of 577 patients. Two studies evaluated patients with cervicogenic headache, 2 evaluated patients with tension-type headache, one study assessed patients with migraine, and the remaining 3 evaluated patients with mixed-type headache (tension-type headache/migraine). Quality ratings ranged from low (3/10) to high (7/10). The effectiveness of DN was similar to that of the other interventions. DN was associated with significant improvements in functional and sensory outcomes. Conclusions Dry needling should be considered for the treatment of headache, and may be applied either alone or in combination with pharmacological treatments

    Effects of ischemic compression on trigger points in the first dorsal interosseous muscle in patients with thumb carpometacarpal osteoarthritis

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    Background: Thumb carpometacarpal osteoarthritis (CMC OA) is a common disorder that interferes with the ability to perform the activities of daily life. The purpose of this study was to investigate the immediate effects of ischemic compression on myofascial trigger points (MTrPs) in the first dorsal interosseous (FDI) muscle in patients with the diagnosis of thumb CMC OA. Methods: In a quasi-experimental clinical trial, thirty-one patients, 87% female (age: 82 ± 9.4 years), with thumb CMC OA, were consecutively assigned to either an experimental treatment that included the ischemic compression of the FDI MTrP or a sham treatment of the FDI MTrP for one session. The main outcome considered in the study was the pressure pain threshold (PPT). Measurements were taken pre-and post-treatment and at a 1-week follow-up period. Results: The PPT over the right (affected) FDI muscle showed statistically significant differences between groups at 1-week follow up (F = 3.518; p = 0.04) in favor of the experimental group. Conclusions: The ischemic compression of FDI-MTrPs is an appropriate part of a multimodal treatment to decrease local pain sensitivity in patients with CMC OA

    Treatment patterns for metastatic colorectal cancer in Spain

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    Abstract Purpose The primary aim of this retrospective study was to describe the treatment patterns according to the type of treatment received by patients with metastatic colorectal cancer (mCRC) in Spain. Methods This was a retrospective, observational, multicenter study performed by 33 sites throughout Spain that included consecutive patients aged 18 years or older who had received or were receiving treatment for mCRC. Results At the time of inclusion, of the 873 evaluable patients, 507 (58%) had received two lines, 235 (27%) had received three lines, 106 (12%) had received four lines, and the remaining patients had received up to ten lines. The most frequent chemotherapy schemes were the FOLFOX or CAPOX regimens (66%) for frst-line treatment, FOLFOX, CAPOX or FOLFIRI (70%) for second-line treatment, and FOLFOX, FOLFIRI or other fuoropyrimidine-based regimens for third- and fourth-line (over 60%) treatment. Sixty percent of patients received targeted therapy as part of their frst-line treatment, and this proportion increased up to approximately 70% of patients as part of the second-line of treatment. A relevant proportion of patients were treated with unknown KRAS, and especially the BRAF, mutation statuses. Conclusions This study reveals inconsistencies regarding adherence to the recommendations of the ESMO guidelines for the management of mCRC in Spain. Improved adherence to the standard practice described in such guidelines for the determination of RAS and BRAF mutation statuses and the use of targeted therapies in frst-line treatment should be considered to guarantee that patients can beneft from the best therapeutic approaches available. Keywords Colorectal cancer · Metastatic · Treatment patterns · KRAS/BRAF mutation status · Clinical practice guidelin

    Influence of seat-belt use on the severity of injury in traffic accidents

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    ABSTRACT: Background: About 1.35 million people died in traffic accidents around the world in 2018, make this type of accidents the 8th cause of death in the world. Particularly, in Spain, there were 204,596 traffic accidents during 2016 and 2017, out of which 349,810 drivers were injured. The objective of this study was to understand to what extent seat belt non-use and human factors contribute to drivers injury severity. Methodology: The results are based on the information and 2016-17 data provided by the Spain national traffic department "Dirección General de Tráfico" (DGT). The discretization model and Bayesian Networks were developed based on important variables from the literature. These variables were classified as; human factor, demographic factor, conditioning factor and seat belt use. Results: The results showed that failure to wear the seat belt by drivers are likely to increase the risk of fatal and sever injury significantly. Moreover, distraction and road type road can contribute to the accident severity

    Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept

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    We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactorsand the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40\,cm long gas cell placed in the beam path of the Aries 40\,m radio telescope receivers operating in the 41-49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH3OH, CH3CH2OH, HCOOH, OCS,CS, SO2 (<1E-03 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O2 and CS2 was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.Comment: Accepted for publication in Astronomy and Astrophysics in September 21, 2017. 16 pages, 18 figure

    Chemical composition of Galactic OB stars I. CNO abundances in O9 stars

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    We present NLTE abundances of CNO for a sample of four O9 stars in the Galaxy, together with new determinations of their stellar parameters, TeffT_{\rm eff}, logg\log g, ϵ\epsilon(He) and microturbulence. These new analyses take into account the effect of {\it line--blocking} in the spectral synthesis with our classical NLTE, plane--parallel and hydrostatic model atmospheres. The sample includes three O9 He normal stars: two dwarfs, HD 214680 and HD 34078, and one supergiant, HD 209975, and one fast rotating giant with a preliminary high He overabundance, HD 191423 with ϵ\epsilon(He)=0.20. We find first that the consideration of microturbulence in the spectral synthesis for the fast rotator leads to a considerably lower He abundance, ϵ\epsilon(He)=0.12. The CNO abundances of the three He normal stars are in good agreement with the values in the literature for Galactic B dwarfs with no evidence of mixing, and show that they all have the same chemical composition. We also discuss however the possible CNO contamination of the supergiant HD 209975. For the fast rotator we find that the abundances show the trend of the CNO contamination: a N overabundance together with C and O depletion. The N/C and N/O ratios of our stars as a function of their projected rotational velocities are consistent with the predictions of the recent evolutionary models of Meynet & Maeder [Mey&Mae00].Comment: 19 pages, 12 figures, 13 tables, accepted by A&

    Active study: undetected prevalence and clinical inertia in the treatment of breakthrough cancer pain (BTcP)

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    Aims To prove if there is clinical inertia in the identification and treatment of episodes of breakthrough cancer pain (BTcP), comparing actual results from clinical practice with clinical oncologists’ prior perception. Design Observational and descriptive study, using information collected by practising medical oncologists, at three moments: (a) questionnaire regarding their professional judgement of the handling of patients with BTcP in their practice, (b) cross-sectional clinical screening, to detect possible existing cases of BTcP in a representative sample of their patients, (c) retrospective self-audit of clinical case histories of patients diagnosed with BTcP to find out about how it has been handled. Participants and study period A random sample on a state level of 108 specialists in medical oncology. 540 patients who suffer some type of cancer pain on the designated study date for each specialist (July–December 2016). Results The global prevalence of BTcP in the study sample covered 91.3% of the patients who were suffering some type of cancer pain. Barely 2% of the doctors surveyed suspected figures around this mark. 40.9% of the cases had not been previously detected as BTcP by their doctors. Although 90% of the patients who had previously been diagnosed with BTcP received a specific analgesic treatment for the symptoms, 42% of those patients with known BTcP were not able to control their episodes of pain. Conclusions Clinical inertia is a serious problem in the handling of BTcP in medical oncology services, where it is the subject of a significantly low level of detection and treatment, despite the contrasting perception of specialists.pre-print339 K
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