766 research outputs found
Sinus elevation by in situ utilization of bone scrapers : technique and results
Objectives: The objective was to present a novel technique for antrostomy performed before sinus elevation in atrophic maxilla for subsequent implant placement. Material and methods: The study included 10 sinus elevations performed by the proposed technique in nine consecutive patients presenting with inadequate posterior maxillary height. The technique is described, calculating the antrostomy surface area, volume of bone tissue obtained and final height attained in each case. A total of 16 implants were placed. Results: All ten elevations were accomplished. Mean antrostomy surface area was 0.55 mm2 , mean bone volume obtained was 0.56 cm3 and mean height attained was 11.7 mm from a baseline mean height of 5.6 mm. Out of the 16 implants, 14 were inserted immediately after the elevation and 2 were inserted in a second step, after ossification; 93.7% of the implants were osseointegrated at 6 months after prosthesis placement. Conclusion: The use of bone scrapers to create antrostomy for sinus elevation is a simple and very safe procedure. It provides a variable amount of particulate bone graft that is easily handled and highly useful for packing the cavity that will elevate the sinus membrane
Análise do comportamento de lentes em vidro de sílica perante a utilização de radiação solar concentrada
CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMO: Este trabalho descreve os ensaios realizados com um simulador laboratorial de radiação solar concentrada com o objectivo de avaliar o comportamento de lentes em vidro de sílica quando sujeitas a elevados fluxos de radiação, e permitiu comparar o seu comportamento com o que foi demonstrado por lentes idênticas, mas fabricadas em vidro de borossilicato (BK-7) cujo preço é muito inferior. Os ensaios de irradiação das lentes atingiram durações de 60 minutos, durante os quais se procedeu à monitorização contínua da potência da radiação aplicada sobre cada lente e da temperatura nela gerada. Todas as lentes em vidro de sílica se comportaram bem, mas o mesmo não ocorreu com as lentes em vidro de borossilicato. No trabalho é aventada a hipótese de o comportamento negativo registado nas lentes em borossilicato ser provocado pelo facto de se ter usado a radiação emitida por uma lâmpada de arco de xénon que pode conter comprimentos de onda que estão ausentes na radiação solar, pelo que é proposto que nos futuros testes não se use um simulador de radiação solar.ABSTRACT: This work describes the tests conducted with a laboratory-scale high-flux solar simulator aiming to evaluate the performance of optical lenses made of silica glass when subjected to high-fluxes of radiation, and it allowed to compare their behaviour with the behaviour shown by lenses made of borosilicate glass (BK-7) which price is much lower. The irradiation tests reached durations up to 60 minutes, with continuous monitoring of the power irradiating each and of the temperature generated on it. All silica lenses have shown a good performance, contrarily to what was observed with the lenses made of borosilicate. In the work it is mentioned the possibility that the negative behaviour observed with the borosilicate lenses may be due to the fact that the radiation spectrum of a xenon arc lamp contains certain wavelengths that are not present in the solar radiation spectrum, and therefore it is suggested that future tests are conducted with real concentrated solar radiation and not with a simulator that artificially reproduces the solar energy distribution.info:eu-repo/semantics/publishedVersio
Sex-related differences of fatty acid-binding protein 4 and leptin levels in atrial fibrillation
Aims: Adiposity plays a key role in the pathogenesis of atrial fibrillation (AF). Our aim was to study the sex differences in adipokines levels according to AF burden. Methods and results: Two independent cohorts of patients were studied: (i) consecutive patients with AF undergoing catheter ablation (n = 217) and (ii) a control group (n = 105). (i) Adipokines, oxidative stress, indirect autonomic markers, and leucocytes mRNA levels were analysed; (ii) correlation between biomarkers was explored with heatmaps and Kendall correlation coefficients; and (iii) logistic regression and random forest model were used to determine predictors of AF recurrence after ablation. Our results showed that: (i) fatty acid-binding protein 4 (FABP4) and leptin levels were higher in women than in men in both cohorts (P < 0.01). In women, FABP4 levels were higher on AF cohort (20 ± 14 control, 29 ± 18 paroxysmal AF and 31 ± 17 ng/mL persistent AF; P < 0.01). In men, leptin levels were lower on AF cohort (22 ± 15 control, 13 ± 16 paroxysmal AF and 13 ± 11 ng/mL persistent AF; P < 0.01). (ii) In female with paroxysmal AF, there was a lower acetylcholinesterase and higher carbonic anhydrase levels with respect to men (P < 0.05). (iii) Adipokines have an important role on discriminate AF recurrence after ablation. In persistent AF, FABP4 was the best predictor of recurrence after ablation (1.067, 95% confidence interval 1-1.14; P = 0.046). Conclusion: The major finding of the present study is the sex-based differences of FABP4 and leptin levels according to AF burden. These adipokines are associated with oxidative stress, inflammatory and autonomic indirect markers, indicating that they may play a role in AF perpetuation.This study was supported by projects (PI16/01282 and PI18/01584) integrated in the Plan Estatal de I+D+I 2016–2019 and cofounded by ISCIII-Subdirección General de Evaluación y Fomento de la Investigación del Fondo Europeo de Desarrollo Regional (FEDER). J.N.L.-C. and M.R.-M. were a recipient of a Sociedade Galega de Cardioloxía (SOGACAR) research grant. D.d.G.-C. was a recipient of a Juan de la Cierva-Incorporación grant from the Ministry of Science Innovation and Universities (IJCI-2016-29393). CIBER Cardiovascular (CB16/11/00403 to V.Ll.-C. and D.d.G.-C.) is a project from Carlos III Health Institute.Peer reviewe
Olaparib in combination with pegylated liposomal doxorubicin for platinum-resistant ovarian cancer regardless of BRCA status : a GEICO phase II trial (ROLANDO study)
There is limited evidence for the benefit of olaparib in platinum-resistant ovarian cancer (PROC) patients with BRCA wild-type tumors. This study investigated whether this combination of a DNA-damaging chemotherapy plus olaparib is effective in PROC regardless BRCA status. Patients with high-grade serous or endometrioid ovarian carcinoma and one previous PROC recurrence were enrolled regardless of BRCA status. Patients with ≤4 previous lines (up to 5 in BRCA -mut) with at least one previous platinum-sensitive relapse were included; primary PROC was allowed only in case of BRCA -mut. Patients initially received six cycles of olaparib 300 mg b.i.d. (biduum) + intravenous pegylated liposomal doxorubicin (PLD) 40 mg/m 2 (PLD40) every 28 days, followed by maintenance with olaparib 300 mg b.i.d. until progression or toxicity. The PLD dose was reduced to 30 mg/m 2 (PLD30) due to toxicity. The primary endpoint was progression-free survival (PFS) at 6 months (6m-PFS) by RECIST version 1.1. A proportion of 40% 6m-PFS or more was considered of clinical interest. From 2017 to 2020, 31 PROC patients were included. BRCA mutations were present in 16%. The median of previous lines was 2 (range 1-5). The overall disease control rate was 77% (partial response rate of 29% and stable disease rate of 48%). After a median follow-up of 10 months, the 6m-PFS and median PFS were 47% and 5.8 months, respectively. Grade ≥3 treatment-related adverse events occurred in 74% of patients, with neutropenia/anemia being the most frequent. With PLD30 serious AEs were less frequent than with PLD40 (21% versus 47%, respectively); moreover, PLD30 was associated with less PLD delays (32% versus 38%) and reductions (16% versus 22%). The PLD-olaparib combination has shown significant activity in PROC regardless of BRCA status. PLD at 30 mg/m 2 is better tolerated in the combination
Dynamical Patterns of Cattle Trade Movements
Despite their importance for the spread of zoonotic diseases, our
understanding of the dynamical aspects characterizing the movements of farmed
animal populations remains limited as these systems are traditionally studied
as static objects and through simplified approximations. By leveraging on the
network science approach, here we are able for the first time to fully analyze
the longitudinal dataset of Italian cattle movements that reports the mobility
of individual animals among farms on a daily basis. The complexity and
inter-relations between topology, function and dynamical nature of the system
are characterized at different spatial and time resolutions, in order to
uncover patterns and vulnerabilities fundamental for the definition of targeted
prevention and control measures for zoonotic diseases. Results show how the
stationarity of statistical distributions coexists with a strong and
non-trivial evolutionary dynamics at the node and link levels, on all
timescales. Traditional static views of the displacement network hide important
patterns of structural changes affecting nodes' centrality and farms' spreading
potential, thus limiting the efficiency of interventions based on partial
longitudinal information. By fully taking into account the longitudinal
dimension, we propose a novel definition of dynamical motifs that is able to
uncover the presence of a temporal arrow describing the evolution of the system
and the causality patterns of its displacements, shedding light on mechanisms
that may play a crucial role in the definition of preventive actions
Dynamical Patterns of Cattle Trade Movements
Despite their importance for the spread of zoonotic diseases, our
understanding of the dynamical aspects characterizing the movements of farmed
animal populations remains limited as these systems are traditionally studied
as static objects and through simplified approximations. By leveraging on the
network science approach, here we are able for the first time to fully analyze
the longitudinal dataset of Italian cattle movements that reports the mobility
of individual animals among farms on a daily basis. The complexity and
inter-relations between topology, function and dynamical nature of the system
are characterized at different spatial and time resolutions, in order to
uncover patterns and vulnerabilities fundamental for the definition of targeted
prevention and control measures for zoonotic diseases. Results show how the
stationarity of statistical distributions coexists with a strong and
non-trivial evolutionary dynamics at the node and link levels, on all
timescales. Traditional static views of the displacement network hide important
patterns of structural changes affecting nodes' centrality and farms' spreading
potential, thus limiting the efficiency of interventions based on partial
longitudinal information. By fully taking into account the longitudinal
dimension, we propose a novel definition of dynamical motifs that is able to
uncover the presence of a temporal arrow describing the evolution of the system
and the causality patterns of its displacements, shedding light on mechanisms
that may play a crucial role in the definition of preventive actions
Opinion dynamics: models, extensions and external effects
Recently, social phenomena have received a lot of attention not only from
social scientists, but also from physicists, mathematicians and computer
scientists, in the emerging interdisciplinary field of complex system science.
Opinion dynamics is one of the processes studied, since opinions are the
drivers of human behaviour, and play a crucial role in many global challenges
that our complex world and societies are facing: global financial crises,
global pandemics, growth of cities, urbanisation and migration patterns, and
last but not least important, climate change and environmental sustainability
and protection. Opinion formation is a complex process affected by the
interplay of different elements, including the individual predisposition, the
influence of positive and negative peer interaction (social networks playing a
crucial role in this respect), the information each individual is exposed to,
and many others. Several models inspired from those in use in physics have been
developed to encompass many of these elements, and to allow for the
identification of the mechanisms involved in the opinion formation process and
the understanding of their role, with the practical aim of simulating opinion
formation and spreading under various conditions. These modelling schemes range
from binary simple models such as the voter model, to multi-dimensional
continuous approaches. Here, we provide a review of recent methods, focusing on
models employing both peer interaction and external information, and
emphasising the role that less studied mechanisms, such as disagreement, has in
driving the opinion dynamics. [...]Comment: 42 pages, 6 figure
<i>Gaia</i> Data Release 1. Summary of the astrometric, photometric, and survey properties
Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7.
Aims. A summary of Gaia DR1 is presented along with illustrations of the scientific quality of the data, followed by a discussion of the limitations due to the preliminary nature of this release.
Methods. The raw data collected by Gaia during the first 14 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into an astrometric and photometric catalogue.
Results. Gaia DR1 consists of three components: a primary astrometric data set which contains the positions, parallaxes, and mean proper motions for about 2 million of the brightest stars in common with the HIPPARCOS and Tycho-2 catalogues – a realisation of the Tycho-Gaia Astrometric Solution (TGAS) – and a secondary astrometric data set containing the positions for an additional 1.1 billion sources. The second component is the photometric data set, consisting of mean G-band magnitudes for all sources. The G-band light curves and the characteristics of ∼3000 Cepheid and RR-Lyrae stars, observed at high cadence around the south ecliptic pole, form the third component. For the primary astrometric data set the typical uncertainty is about 0.3 mas for the positions and parallaxes, and about 1 mas yr−1 for the proper motions. A systematic component of ∼0.3 mas should be added to the parallax uncertainties. For the subset of ∼94 000 HIPPARCOS stars in the primary data set, the proper motions are much more precise at about 0.06 mas yr−1. For the secondary astrometric data set, the typical uncertainty of the positions is ∼10 mas. The median uncertainties on the mean G-band magnitudes range from the mmag level to ∼0.03 mag over the magnitude range 5 to 20.7.
Conclusions. Gaia DR1 is an important milestone ahead of the next Gaia data release, which will feature five-parameter astrometry for all sources. Extensive validation shows that Gaia DR1 represents a major advance in the mapping of the heavens and the availability of basic stellar data that underpin observational astrophysics. Nevertheless, the very preliminary nature of this first Gaia data release does lead to a number of important limitations to the data quality which should be carefully considered before drawing conclusions from the data
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