226 research outputs found
The role of Dark Matter interaction in galaxy clusters
We consider a toy model to analyze the consequences of dark matter
interaction with a dark energy background on the overall rotation of galaxy
clusters and the misalignment between their dark matter and baryon
distributions when compared to {\Lambda}CDM predictions. The interaction
parameters are found via a genetic algorithm search. The results obtained
suggest that interaction is a basic phenomenon whose effects are detectable
even in simple models of galactic dynamics.Comment: RevTeX 4.1, 5 pages, 3 figure
A visual tool for assessing tension-resolving models in the - plane
Beyond-CDM models, which were proposed to resolve the "Hubble
tension", often have an impact on the discrepancy in the amplitude of matter
clustering, the "-tension". To explore the interplay between the two
tensions, we propose a simple method to visualize the relation between the two
parameters and : For a given extension of the CDM
model and data set, we plot the relation between and for
different amplitudes of the beyond-CDM physics. We use this
visualization method to illustrate the trend of selected cosmological models,
including non-minimal Higgs-like inflation, early dark energy, a varying
effective electron mass, an extra number of relativistic species and modified
dark energy models. We envision that the proposed method could be a useful
diagnostic tool to illustrate the behaviour of complex cosmological models with
many parameters in the context of the and tensions.Comment: 19 pages, 3 figures, 5 table
A system-on-chip microwave photonic processor solves dynamic RF interference in real time with picosecond latency
Radio-frequency interference is a growing concern as wireless technology
advances, with potentially life-threatening consequences like interference
between radar altimeters and 5G cellular networks. Mobile transceivers mix
signals with varying ratios over time, posing challenges for conventional
digital signal processing (DSP) due to its high latency. These challenges will
worsen as future wireless technologies adopt higher carrier frequencies and
data rates. However, conventional DSPs, already on the brink of their clock
frequency limit, are expected to offer only marginal speed advancements. This
paper introduces a photonic processor to address dynamic interference through
blind source separation (BSS). Our system-on-chip processor employs a fully
integrated photonic signal pathway in the analogue domain, enabling rapid
demixing of received mixtures and recovering the signal-of-interest in under 15
picoseconds. This reduction in latency surpasses electronic counterparts by
more than three orders of magnitude. To complement the photonic processor,
electronic peripherals based on field-programmable gate array (FPGA) assess the
effectiveness of demixing and continuously update demixing weights at a rate of
up to 305 Hz. This compact setup features precise dithering weight control,
impedance-controlled circuit board and optical fibre packaging, suitable for
handheld and mobile scenarios. We experimentally demonstrate the processor's
ability to suppress transmission errors and maintain signal-to-noise ratios in
two scenarios, radar altimeters and mobile communications. This work pioneers
the real-time adaptability of integrated silicon photonics, enabling online
learning and weight adjustments, and showcasing practical operational
applications for photonic processing
Prediction of intensive care admission and hospital mortality in COVID-19 patients using demographics and baseline laboratory data
Introduction: Optimized allocation of medical resources to patients with COVID-19 has been a critical concern since the onset of the pandemic.
Methods: In this retrospective cohort study, the authors used data from a Brazilian tertiary university hospital to explore predictors of Intensive Care Unit (ICU) admission and hospital mortality in patients admitted for COVID-19. Our primary aim was to create and validate prediction scores for use in hospitals and emergency departments to aid clinical decisions and resource allocation.
Results: The study cohort included 3,022 participants, of whom 2,485 were admitted to the ICU; 1968 survived, and 1054 died in the hospital. From the complete cohort, 1,496 patients were randomly assigned to the derivation sample and 1,526 to the validation sample. The final scores included age, comorbidities, and baseline laboratory data. The areas under the receiver operating characteristic curves were very similar for the derivation and validation samples. Scores for ICU admission had a 75% accuracy in the validation sample, whereas scores for death had a 77% accuracy in the validation sample. The authors found that including baseline flu-like symptoms in the scores added no significant benefit to their accuracy. Furthermore, our scores were more accurate than the previously published NEWS-2 and 4C Mortality Scores.
Discussion and conclusions: The authors developed and validated prognostic scores that use readily available clinical and laboratory information to predict ICU admission and mortality in COVID-19. These scores can become valuable tools to support clinical decisions and improve the allocation of limited health resources
Loss of material in Shotcrete
O concreto projetado é muito viável para contenção de encostas, túneis, entre outros. Além de ter
uma vantagem econômica, pois não utiliza o sistema de fôrmas. Isto devido ao fato de ser um
concreto que é, como o próprio nome diz, projetado na superfície e com a força da projeção se adere
a esta. Existem dois tipos de concreto projetado: por via seca e por via úmida, neste trabalho iremos
tratar especificamente do projetado por via seca, onde as partículas sólidas encontram a água (e
aditivos, se for o caso) somente no bico de projeção. O objetivo é estudar e analisar o desperdício
causado pela aplicação do concreto projetado por via seca, que é um de seus pontos negativos, em
uma obra de contenção, localizada no munícipio de Niterói/RJ e indicar algumas formas de
reutilizá-lo na obra.The shotcrete is very feasible for containment of slopes, tunnels, among others. Besides having an
economic advantage, it does not use the system of forms. This is due to the fact that it is a concrete
that is, as the name says, projected on the surface and with the force of the projection sticking to the
surface. There are two types of projected concrete: dry shot and wet shot, in this work we will
specifically deal with the dry shot, where the solid particles find the water (and additives, if any) in
the projection nozzle only. The objective is to study and analyze the waste caused by the application
of shotcrete, which is one of its negative points, in a containment work, located in the municipality
of Niterói/RJ and indicate some ways to reuse it in the work
Mortality inequalities measured by socioeconomic indicators in Brazil: a scoping review
OBJECTIVE Summarize the literature on the relationship between composite socioeconomic indicators and mortality in different geographical areas of Brazil. METHODS This scoping review included articles published between January 1, 2000, and August 31, 2020, retrieved by means of a bibliographic search carried out in the Medline, Scopus, Web of Science, and Lilacs databases. Studies reporting on the association between composite socioeconomic indicators and all-cause, or specific cause of death in any age group in different geographical areas were selected. The review summarized the measures constructed, their associations with the outcomes, and potential study limitations. RESULTS Of the 77 full texts that met the inclusion criteria, the study reviewed 24. The area level of composite socioeconomic indicators analyzed comprised municipalities (n = 6), districts (n = 5), census tracts (n = 4), state (n = 2), country (n = 2), and other areas (n = 5). Six studies used composite socioeconomic indicators such as the Human Development Index, Gross Domestic Product, and the Gini Index; the remaining 18 papers created their own socioeconomic measures based on sociodemographic and health indicators. Socioeconomic status was inversely associated with higher rates of all-cause mortality, external cause mortality, suicide, homicide, fetal and infant mortality, respiratory and circulatory diseases, stroke, infectious and parasitic diseases, malnutrition, gastroenteritis, and oropharyngeal cancer. Higher mortality rates due to colorectal cancer, leukemia, a general group of neoplasms, traffic accident, and suicide, in turn, were observed in less deprived areas and/or those with more significant socioeconomic development. Underreporting of death and differences in mortality coverage in Brazilian areas were cited as the main limitation. CONCLUSIONS Studies analyzed mortality inequalities in different geographical areas by means of composite socioeconomic indicators, showing that the association directions vary according to the mortality outcome. But studies on all-cause mortality and at the census tract level remain scarce. The results may guide the development of new composite socioeconomic indicators for use in mortality inequality analysis
Differentials in death count records by databases in Brazil in 2010
OBJECTIVE To compare the death counts from three sources of information on mortality available in Brazil in 2010, the Mortality Information System (SIM - Sistema de Informações sobre Mortalidade ), Civil Registration Statistic System (RC - Sistema de Estatísticas de Resgistro Civil ), and the 2010 Demographic Census at various geographical levels, and to confirm the association between municipal socioeconomic characteristics and the source which showed the highest death count. METHODS This is a descriptive and comparative study of raw data on deaths in the SIM, RC and 2010 Census databases, the latter held in Brazilian states and municipalities between August 2009 and July 2010. The percentage of municipalities was confirmed by the database showing the highest death count. The association between the source of the highest death count and socioeconomic indicators - the Índice de Privação Brasileiro (IBP – Brazilian Deprivation Index) and Índice de Desenvolvimento Humano Municipal (IHDM – Municipal Human Development Index) - was performed by bivariate choropleth and Moran Local Index of Spatial Association (LISA) cluster maps. RESULTS Confirmed that the SIM is the database with the highest number of deaths counted for all Brazilian macroregions, except the North, in which the highest coverage was from the 2010 Census. Based on the indicators proposed, in general, the Census showed a higher coverage of deaths than the SIM and the RC in the most deprived (highest IBP values) and less developed municipalities (lowest IDHM values) in the country. CONCLUSION The results highlight regional inequalities in how the databases chosen for this study cover death records, and the importance of maintaining the issue of mortality on the basic census questionnaire
Nocturnal Oximetry-based Evaluation of Habitually Snoring Children
Rationale: The vast majority of children around the world
undergoing adenotonsillectomy for obstructive sleep
apnea–hypopnea syndrome (OSA) are not objectively diagnosed by
nocturnal polysomnography because of access availability and cost
issues. Automated analysis of nocturnal oximetry (nSpO2), which is
readily and globally available, could potentially provide a reliable and
convenient diagnostic approach for pediatric OSA.
Methods: DeidentifiednSpO2 recordings froma total of 4,191 children
originating from13 pediatric sleep laboratories around the worldwere
prospectively evaluated after developing and validating an automated
neural network algorithm using an initial set of single-channel nSpO2
recordings from 589 patients referred for suspected OSA.
Measurements and Main Results: The automatically
estimated apnea–hypopnea index (AHI) showed high
agreement with AHI from conventional polysomnography
(intraclass correlation coefficient, 0.785) when tested in 3,602
additional subjects. Further assessment on the widely used AHI
cutoff points of 1, 5, and 10 events/h revealed an incremental
diagnostic ability (75.2, 81.7, and 90.2% accuracy; 0.788, 0.854, and
0.913 area under the receiver operating characteristic curve,
respectively).
Conclusions: Neural network–based automated analyses of
nSpO2 recordings provide accurate identification of OSA
severity among habitually snoring children with a high pretest
probability of OSA. Thus, nocturnal oximetry may enable a
simple and effective diagnostic alternative to nocturnal
polysomnography, leading to more timely interventions and
potentially improved outcomes.Supported in part by project VA037 U16 from the Consejer´ıa de Educacio´ n de la Junta de Castilla y Leo´ n and the European Regional Development Fund (FEDER), project RTC-2015-3446-1 from the Ministerio de Econom´ıa y Competitividad and FEDER, and project 153/2015 of the Sociedad Espan˜ ola de Neumolog´ıa y Cirug´ıa Tora´ cica (SEPAR). L.K.-G. is supported by NIH grant 1R01HL130984. M.F.P. was supported by a Fellowship Educational grant award from the Kingdom of Saudi Arabia. D.´A. was in receipt of a Juan de la Cierva grant from the Ministerio de Econom´ıa y Competitividad. The funders played no role in the study design, data collection, data analysis, interpretation, and writing of the manuscript
Choque antropológico e o sujeito contemporâneo: Ulrich Beck entre a ecologia, a sociologia e a política
Um estudo retrospectivo dos aspectos epidemiológicos da tuberculose na comunidade do Complexo de Manguinhos localizado em área urbana do Rio de Janeiro, Brasil, 2000-2002
- …