60 research outputs found
Infrared excesses in stars with and without planets using revised photometry
We present an analysis on the potential prevalence of mid infrared excesses
in stars with and without planetary companions. Based on an extended database
of stars detected with the satellite, we studied two stellar
samples: one with 236 planet hosts and another with 986 objects for which
planets have been searched but not found. We determined the presence of an
excess over the photosphere by comparing the observed flux ratio at 22 m
and 12 m () with the corresponding synthetic value, derived
from results of classical model photospheres. We found a detection rate of
0.85 at 22 m (2 excesses) in the sample of stars with planets and
0.1 (1 detection) for the stars without planets. The difference of the
detection rate between the two samples is not statistically significant, a
result that is independent of the different approaches found in the literature
to define an excess in the wavelength range covered by
observations. As an additional result, we found that the fluxes
required a normalisation procedure to make them compatible with synthetic data,
probably pointing out a revision of the data calibration.Comment: 10 pages, 6 figures, 3 tables. Accepted for publication in MNRA
Imágenes satelitárias para detección y monitoreo operacional de los cambios en el bosque nativo del norte de la provincia de Entre RÃos
Este trabajo presenta el Proyecto trianual actualmente en ejecución en la Facultad de Ciencia y TecnologÃa de UADER-Universidad Autónoma de Entre RÃos. Eneste proyecto se desarrolla un sistema operacional para el monitoreo de cambios interanuales en la cobertura vegetal del bosque nativo del centronorte de Entre RÃos utilizando imágenes digitales obtenidas en el espectro óptico por satélites orbitales. Para ello se adaptan técnicas digitales de procesamiento de imágenes para la detección de cambios en la vegetación en los ambientes sub-húmedos del norte provincial.
La metodologÃa posibilitará el monitoreo operacional a partir de imágenes satelitales de diferentes sensores. Las técnicas articuladas por esta metodologÃa permiten la detección de cambios entre imágenes de sensores espectralmente compatibles, con o sin calibración atmosférica. Estas además son resistentes a la confusión producida por la dinámica compleja de la cobertura vegetal del área y capaces de incorporar las nuevas tecnologÃas satelitales actualmente en desarrollo. Los resultados y metodologÃas desarrolladas en el marco del proyecto permitirán establecer para el futuro un sistema operacional de monitoreo de la cobertura de bosques en la región permitiendo a la Provincia contar con herramientas para monitoreo del cumplimiento de la Ley de Presupuestos MÃnimos de Protección Ambiental de los Bosques Nativos de la Ley Nacional de Bosques 26331.Eje: Computación Gráfica, Imágenes y VisualizaciónRed de Universidades con Carreras en Informática (RedUNCI
Unconventional human CD61 pairing with CD103 promotes TCR signaling and antigen-specific T cell cytotoxicity
Cancer remains one of the leading causes of mortality worldwide, leading to increased interest in utilizing immunotherapy strategies for better cancer treatments. In the past decade, CD103+Â T cells have been associated with better clinical prognosis in patients with cancer. However, the specific immune mechanisms contributing toward CD103-mediated protective immunity remain unclear. Here, we show an unexpected and transient CD61 expression, which is paired with CD103 at the synaptic microclusters of T cells. CD61 colocalization with the T cell antigen receptor further modulates downstream T cell antigen receptor signaling, improving antitumor cytotoxicity and promoting physiological control of tumor growth. Clinically, the presence of CD61+Â tumor-infiltrating T lymphocytes is associated with improved clinical outcomes, mediated through enhanced effector functions and phenotype with limited evidence of cellular exhaustion. In conclusion, this study identified an unconventional and transient CD61 expression and pairing with CD103 on human immune cells, which potentiates a new target for immune-based cellular therapies
Timescales of Multineuronal Activity Patterns Reflect Temporal Structure of Visual Stimuli
The investigation of distributed coding across multiple neurons in the cortex remains to this date a challenge. Our current understanding of collective encoding of information and the relevant timescales is still limited. Most results are restricted to disparate timescales, focused on either very fast, e.g., spike-synchrony, or slow timescales, e.g., firing rate. Here, we investigated systematically multineuronal activity patterns evolving on different timescales, spanning the whole range from spike-synchrony to mean firing rate. Using multi-electrode recordings from cat visual cortex, we show that cortical responses can be described as trajectories in a high-dimensional pattern space. Patterns evolve on a continuum of coexisting timescales that strongly relate to the temporal properties of stimuli. Timescales consistent with the time constants of neuronal membranes and fast synaptic transmission (5–20 ms) play a particularly salient role in encoding a large amount of stimulus-related information. Thus, to faithfully encode the properties of visual stimuli the brain engages multiple neurons into activity patterns evolving on multiple timescales
Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study
Summary
Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally.
Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies
have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of
the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income
countries globally, and identified factors associated with mortality.
Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to
hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis,
exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a
minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical
status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary
intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause,
in-hospital mortality for all conditions combined and each condition individually, stratified by country income status.
We did a complete case analysis.
Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital
diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal
malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome
countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male.
Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3).
Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income
countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups).
Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome
countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries;
p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients
combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11],
p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20
[1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention
(ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety
checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed
(ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of
parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65
[0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality.
Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome,
middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will
be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger
than 5 years by 2030
Modulation by polyamines of apoptotic pathways triggered by procyanidins in human metastatic SW620 cells.
International audienceWe showed previously that inhibition of polyamine catabolism with the polyamine oxidase inhibitor MDL 72527 (MDL) potentiates the apoptotic effects of apple procyanidins (Pcy) in SW620 cells. Here we report that Pcy caused an activation of the intrinsic apoptotic pathway through enhanced polyamine catabolism and mitochondrial membrane depolarization. MDL in the presence of Pcy caused a profound intracellular depletion of polyamines and exerted a protective effect on mitochondrial functions. MDL potentiation of Pcy-triggered apoptosis was reversed by addition of exogenous polyamines. In addition, MDL in combination with Pcy activated the extrinsic apoptotic pathway through enhanced TRAIL-death receptor (DR4/DR5) expression. Potentiation of Pcy-triggered apoptosis by MDL was inhibited when cells were exposed to specific inhibitors of DR4/DR5. These data indicate that the depletion of intracellular polyamines by MDL in the presence of Pcy caused a switch from intrinsic to extrinsic apoptotic pathways in human colon cancer-derived metastatic cells
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