5,072 research outputs found
Hospital volume and outcomes for acute pulmonary embolism: Multinational population based cohort study
[Objectives] To evaluate the association between experience in the management of acute pulmonary embolism, reflected by hospital case volume, and mortality.[Design] Multinational population based cohort study using data from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) registry between 1 January 2001 and 31 August 2018.[Setting] 353 hospitals in 16 countries.[Participants] 39 257 consecutive patients with confirmed diagnosis of acute symptomatic pulmonary embolism.[Main] outcome measure Pulmonary embolism related mortality within 30 days after diagnosis of the condition.[Results] Patients with acute symptomatic pulmonary embolism admitted to high volume hospitals (>40 pulmonary embolisms per year) had a higher burden of comorbidities. A significant inverse association was seen between annual hospital volume and pulmonary embolism related mortality. Admission to hospitals in the highest quarter (that is, >40 pulmonary embolisms per year) was associated with a 44% reduction in the adjusted odds of pulmonary embolism related mortality at 30 days compared with admission to hospitals in the lowest quarter (<15 pulmonary embolisms per year; adjusted risk 1.3% v 2.3%; adjusted odds ratio 0.56 (95% confidence interval 0.33 to 0.95); P=0.03). Results were consistent in all sensitivity analyses. All cause mortality at 30 days was not significantly reduced between the two quarters (adjusted odds ratio 0.78 (0.50 to 1.22); P=0.28). Survivors showed little change in the odds of recurrent venous thromboembolism (odds ratio 0.76 (0.49 to 1.19)) or major bleeding (1.07 (0.77 to 1.47)) between the low and high volume hospitals.[Conclusions] In patients with acute symptomatic pulmonary embolism, admission to high volume hospitals was associated with significant reductions in adjusted pulmonary embolism related mortality at 30 days. These findings could have implications for management strategies.Peer reviewe
LICOR-Liquid Columns' Resonances
The aim of the experiment LICOR was the investigation of the axial resonances oi cylindrical liquid columns supported by equal circular coaxiaJ disks. In preparation ot the D-2 experiment a •heoreiical model has been developed, which exactly describes the small amplitude oscillations of finite cylindrical columns between coaxial circular disks. In addition, in terrestrial experiments the resonance frequencies of small liquid columns with up to 5 mm in diameter have been determined and investigations with density-matched liquids (silicon oil in a waierlmethanol mixture) have been performed. For the D-2 experiment LICOR the front disk and the rear disk lor use in the AFPM have been constructed and equipped with pressure sensors and the necessary electronics. The pressure exerted by the oscillating liquid column on trie supporting disks vsas as low as 10 Pa. Since the data downlink of the Materials Research Laboratory was just one signal oer second and channel, it was necessary to determine amplitude and phase of the pressure already in the LICOR disks. The D-2 experiment has been successfully performed. It has fully confirmed the theoretical models and remarkably supplements the experiments on small liquid columns and on density-matched columns
Reconstructing native American migrations from whole-genome and whole-exome data.
There is great scientific and popular interest in understanding the genetic history of populations in the Americas. We wish to understand when different regions of the continent were inhabited, where settlers came from, and how current inhabitants relate genetically to earlier populations. Recent studies unraveled parts of the genetic history of the continent using genotyping arrays and uniparental markers. The 1000 Genomes Project provides a unique opportunity for improving our understanding of population genetic history by providing over a hundred sequenced low coverage genomes and exomes from Colombian (CLM), Mexican-American (MXL), and Puerto Rican (PUR) populations. Here, we explore the genomic contributions of African, European, and especially Native American ancestry to these populations. Estimated Native American ancestry is 48% in MXL, 25% in CLM, and 13% in PUR. Native American ancestry in PUR is most closely related to populations surrounding the Orinoco River basin, confirming the Southern American ancestry of the Taíno people of the Caribbean. We present new methods to estimate the allele frequencies in the Native American fraction of the populations, and model their distribution using a demographic model for three ancestral Native American populations. These ancestral populations likely split in close succession: the most likely scenario, based on a peopling of the Americas 16 thousand years ago (kya), supports that the MXL Ancestors split 12.2kya, with a subsequent split of the ancestors to CLM and PUR 11.7kya. The model also features effective populations of 62,000 in Mexico, 8,700 in Colombia, and 1,900 in Puerto Rico. Modeling Identity-by-descent (IBD) and ancestry tract length, we show that post-contact populations also differ markedly in their effective sizes and migration patterns, with Puerto Rico showing the smallest effective size and the earlier migration from Europe. Finally, we compare IBD and ancestry assignments to find evidence for relatedness among European founders to the three populations
Insights into Dark Matter Direct Detection Experiments: Decision Trees versus Deep Learning
The detection of Dark Matter (DM) remains a significant challenge in particle
physics. This study exploits advanced machine learning models to improve
detection capabilities of liquid xenon time projection chamber experiments,
utilizing state-of-the-art transformers alongside traditional methods like
Multilayer Perceptrons and Convolutional Neural Networks. We evaluate various
data representations and find that simplified feature representations,
particularly corrected S1 and S2 signals, retain critical information for
classification. Our results show that while transformers offer promising
performance, simpler models like XGBoost can achieve comparable results with
optimal data representations. We also derive exclusion limits in the
cross-section versus DM mass parameter space, showing minimal differences
between XGBoost and the best performing deep learning models. The comparative
analysis of different machine learning approaches provides a valuable reference
for future experiments by guiding the choice of models and data representations
to maximize detection capabilities.Comment: 26 pages, 7 figures, 2 table
Dark matter candidates in the NMSSM with RH neutrino superfields
R-parity conserving supersymmetric models with right-handed (RH) neutrinos
are very appealing since they could naturally explain neutrino physics and also
provide a good dark matter (DM) candidate such as the lightest supersymmetric
particle (LSP). In this work we consider the next-to-minimal supersymmetric
standard model (NMSSM) plus RH neutrino superfields, with effective Majorana
masses dynamically generated at the electroweak scale (EW). We perform a scan
of the relevant parameter space and study both possible DM candidates: RH
sneutrino and neutralino. Especially for the case of RH sneutrino DM we analyse
the intimate relation between both candidates to obtain the correct amount of
relic density. Besides the well-known resonances, annihilations through scalar
quartic couplings and coannihilation mechanisms with all kind of neutralinos,
are crucial. Finally, we present the impact of current and future direct and
indirect detection experiments on both DM candidates.Comment: Version published in JCAP, 40 pages, 8 figures, 6 table
Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.
OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age
The atmospheric science of JEM-EUSO
An Atmospheric Monitoring System (AMS) is critical suite of instruments for JEM-EUSO whose aim is to detect Ultra-High Energy Cosmic Rays (UHECR) and (EHECR) from Space. The AMS
comprises an advanced space qualified infrared camera and a LIDAR with cross checks provided by a ground-based and airborne Global Light System Stations. Moreover the Slow Data Mode of JEM-EUSO has been proven crucial for the UV background analysis by comparing the UV and IR images. It will also contribute to the investigation of atmospheric effects seen in the data from the GLS or even to our understanding of Space Weather
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
Influence of time of birth in early neonatal mortality and morbidity:retrospective cohort study
Background A key target of the 2030 Sustainable Development Goals is to eliminate preventable deaths in newborns and children under 5. This study aimed to estimate the effect of time of birth on early neonatal mortality (ENM) and low Apgar scores at 5 min (LA5) in newborns. Methods A retrospective cohort study was conducted using vital statistics data on live births, maternal morbidity, congenital defects and perinatal mortality in Cauca-Colombia (2017-2021) excluding out-of-hospital, multiple and major defect cases. A directed acyclic graph was constructed to define the confounder adjustment set. Multivariable logistic, linear and propensity score models evaluated the effect of birth timing on neonatal outcomes, estimating crude and adjusted incidence rate ratios (IRRa). Results We assessed 65 182 live births, finding similar baseline characteristics for daytime and night-time births. ENM was 0.2% (95% CI 0.19% to 0.26%) at 7 days of follow-up, absolute mortality difference 0.1% (95% CI -0.01% to 0.12%). Night-time births increased the incidence of ENM in the primary analysis IRRa 1.27 (95% CI 0.90 to 1.82), in the secondary IRRa 1.45 (95% CI 0.94 to 2.20), and in the primary and secondary sensitivity analysis, respectively, IRRa 1.48 (95% CI 1.06 to 2.07) and 1.70 (95% CI 1.16 to 2.59). LA5 was present in 0.7% (95% CI 0.60% to 0.72%) of birth, with absolute LA5 difference 0.1% (95% CI -0.02% to 0.22%). Night-time births increased the incidence of LA5 in the primary analysis IRRa 1.31 (95% CI 1.00 to 1.49), in the secondary IRRa 1.44 (95% CI 1.13 to 1.83), and in the primary and secondary sensitivity analysis, respectively, IRRa 1.31 (95% CI 1.08 to 1.59) and IRRa 1.54 (95% CI 1.23 to 1.92). Conclusions Birth at night-time is associated with worse neonatal outcomes, ENM and low Apgar scores in Colombia's diverse population, highlighting the need for optimised prenatal care, revised work schedules and improved referral systems in maternal health.</p
Reconfigurable frequency multipliers based on graphene field‑effect transistors
This work is part of the research project P21_00149 ENERGHENE funded by Consejería de Universidad, Investigación e Innovación de
la Junta de Andalucía. This work is also supported by FEDER/Junta de Andalucía - Consejería de Transformación Económica, Industria, Conocimiento
y Universidades through the projects P20-00633 and A-TIC-646-UGR20, by Spanish Government through projects PID2020-116518GBI00
funded by MCIN/AEI/10.13039/501100011033 and TED2021-129769B-I00 funded by MCIN/AEI/10.13039/501100011033 and the European
Union NextGenerationEU/PRTR. F. Pasadas acknowledges funding from PAIDI 2020 and the European Social Fund Operational Programme
2014-2020 no. 20804. M. D. Ganeriwala acknowledges funding from the European Union’s Horizon 2020 research and innovation programme
under the Marie Sklodowska-Curie grant agreement No 101032701.Supplementary information The online version contains supplementary material available at
(https://doi.org/10.1186/s11671-023-03884-8).Run-time device-level reconfigurability has the potential to boost the performance and functionality of numerous circuits
beyond the limits imposed by the integration density. The key ingredient for the implementation of reconfigurable
electronics lies in ambipolarity, which is easily accessible in a substantial number of two-dimensional materials, either
by contact engineering or architecture device-level design. In this work, we showcase graphene as an optimal solution
to implement high-frequency reconfigurable electronics. We propose and analyze a split-gate graphene field-effect
transistor, demonstrating its capability to perform as a dynamically tunable frequency multiplier. The study is based on
a physically based numerical simulator validated and tested against experiments. The proposed architecture is evaluated
in terms of its performance as a tunable frequency multiplier, able to switch between doubler, tripler or quadrupler
operation modes. Different material and device parameters are analyzed, and their impact is assessed in terms of the
reconfigurable graphene frequency multiplier performance.Research project P21_00149 ENERGHENE funded by Consejería de Universidad, Investigación e Innovación de la Junta de AndalucíaFEDER/Junta de Andalucía - Consejería de Transformación Económica, Industria, Conocimiento y Universidades through the projects P20-00633 and A-TIC-646-UGR20Spanish Government through projects PID2020-116518GBI00MCIN/AEI/10.13039/501100011033European Union NextGenerationEU/PRTRPAIDI 2020 and the European Social Fund Operational Programme 2014-2020 no. 20804.European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 10103270
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