The recurrent nova RS Oph: A possible scenario for type Ia supernovae

The recurrent nova RS Oph experienced an outburst in 2006, 21 years after its previous explosion in 1985, as expected. It was observed at almost all wavelengths, and important information about its properties is still being extracted. We present theoretical models of the explosion of this fascinating object, which indicate that the mass of the accreting white dwarf should be very close to the Chandrasekhar mass, to allow for such a short recurrence period. In addition, since models suggest that this nova ejects less mass than it accretes, it is an excellent candidate for a thermonuclear supernova explosion, in about $10^5-10^7$ years from now. We also analyze the emission of soft gamma-rays by RS Oph detected with the BAT instrument onboard Swift, and with the PCA onboard RXTE. We rule out that this emission has its origin in radioactive decays in the expanding nova envelope.Comment: 10 pages, 2 figures, to be published in New Astronomy Review

SampleHST: Efficient On-the-Fly Selection of Distributed Traces

Since only a small number of traces generated from distributed tracing helps in troubleshooting, its storage requirement can be significantly reduced by biasing the selection towards anomalous traces. To aid in this scenario, we propose SampleHST, a novel approach to sample on-the-fly from a stream of traces in an unsupervised manner. SampleHST adjusts the storage quota of normal and anomalous traces depending on the size of its budget. Initially, it utilizes a forest of Half Space Trees (HSTs) for trace scoring. This is based on the distribution of the mass scores across the trees, which characterizes the probability of observing different traces. The mass distribution from HSTs is subsequently used to cluster the traces online leveraging a variant of the mean-shift algorithm. This trace-cluster association eventually drives the sampling decision. We have compared the performance of SampleHST with a recently suggested method using data from a cloud data center and demonstrated that SampleHST improves sampling performance up to by 9.5×

Southern Ocean food-webs and climate change: A short review and future directions

Food-webs are a critical feature of ecosystems and help us understand how communities will respond to climate change. The Southern Ocean is facing rapid and accelerating changes due to climate change. Though having evolved in an isolated and somewhat extreme environment, Southern Ocean biodiversity and food-webs are among the most vulnerable. Here, we review 1) current knowledge on Southern Ocean food-webs; 2) methods to study food-webs; 3) assessment of current and future impacts of climate change on Southern Ocean food-webs; 4) knowledge gaps; and 5) the role of Early Career Researchers (ECRs) in future studies. Most knowledge on Southern Ocean food-webs come from the pelagic environment, both at macro- and microbial levels. Modelling and diet studies of individual species are major contributors to the food-web knowledge. These studies revealed a short food-web, predominantly sustained by Antarctic Krill (Euphausia superba). Additionally, alternative pathways exist, involving other krill species, fish, and squid, which play equally important roles in connecting primary producers with top predators. Advantages and disadvantages of several techniques used to study Southern Ocean food-webs were identified, from the classical analyses of stomach contents, scats, or boluses to the most recent approaches such as metabarcoding and trophic-biomarkers. Observations show that climate change can impact the food-web in different ways. As an example, changes to smaller phytoplankton species can lengthen the food-web, increasing assimilation losses and/or changing nutrient cycles. Future studies need to focus on the benthic-dominated food-webs and the benthopelagic coupling. Furthermore, research during the winter season and below the ice-shelves is needed as these areas may play a crucial role in the functioning of this ecosystem. ECRs can play a significant role in advancing the study of Southern Ocean food-webs due to their willingness for interdisciplinary collaboration and proficiency in employing various methodologies, contributing to the construction of high-resolution food-webs.</jats:p

Southern Ocean food-webs and climate change:A short review and future directions

Food-webs are a critical feature of ecosystems and help us understand how communities will respond to climate change. The Southern Ocean is facing rapid and accelerating changes due to climate change. Though having evolved in an isolated and somewhat extreme environment, Southern Ocean biodiversity and food-webs are among the most vulnerable. Here, we review 1) current knowledge on Southern Ocean food-webs; 2) methods to study food-webs; 3) assessment of current and future impacts of climate change on Southern Ocean food-webs; 4) knowledge gaps; and 5) the role of Early Career Researchers (ECRs) in future studies. Most knowledge on Southern Ocean food-webs come from the pelagic environment, both at macro- and microbial levels. Modelling and diet studies of individual species are major contributors to the food-web knowledge. These studies revealed a short food-web, predominantly sustained by Antarctic Krill (Euphausia superba). Additionally, alternative pathways exist, involving other krill species, fish, and squid, which play equally important roles in connecting primary producers with top predators. Advantages and disadvantages of several techniques used to study Southern Ocean food-webs were identified, from the classical analyses of stomach contents, scats, or boluses to the most recent approaches such as metabarcoding and trophic-biomarkers. Observations show that climate change can impact the food-web in different ways. As an example, changes to smaller phytoplankton species can lengthen the food-web, increasing assimilation losses and/or changing nutrient cycles. Future studies need to focus on the benthic-dominated food-webs and the benthopelagic coupling. Furthermore, research during the winter season and below the ice-shelves is needed as these areas may play a crucial role in the functioning of this ecosystem. ECRs can play a significant role in advancing the study of Southern Ocean food-webs due to their willingness for interdisciplinary collaboration and proficiency in employing various methodologies, contributing to the construction of high-resolution food-webs

Nitrate triggered phosphoproteome changes and a PIN2 phosphosite modulating root system architecture

Nitrate commands genome-wide gene expression changes that impact metabolism, physiology, plant growth, and development. In an effort to identify new components involved in nitrate responses in plants, we analyze the Arabidopsis thaliana root phosphoproteome in response to nitrate treatments via liquid chromatography coupled to tandem mass spectrometry. 176 phosphoproteins show significant changes at 5 or 20 min after nitrate treatments. Proteins identified by 5 min include signaling components such as kinases or transcription factors. In contrast, by 20 min, proteins identified were associated with transporter activity or hormone metabolism functions, among others. The phosphorylation profile of NITRATE TRANSPORTER 1.1 (NRT1.1) mutant plants was significantly altered as compared to wild-type plants, confirming its key role in nitrate signaling pathways that involves phosphorylation changes. Integrative bioinformatics analysis highlights auxin transport as an important mechanism modulated by nitrate signaling at the post-translational level. We validated a new phosphorylation site in PIN2 and provide evidence that it functions in primary and lateral root growth responses to nitrate

Clinical benefit of glasdegib plus low-dose cytarabine in patients with de novo and secondary acute myeloid leukemia: long-term analysis of a phase II randomized trial

This analysis from the phase II BRIGHT AML 1003 trial reports the long-term efficacy and safety of glasdegib + low-dose cytarabine (LDAC) in patients with acute myeloid leukemia ineligible for intensive chemotherapy. The multicenter, open-label study randomized (2:1) patients to receive glasdegib + LDAC (de novo, n = 38; secondary acute myeloid leukemia, n = 40) or LDAC alone (de novo, n = 18; secondary acute myeloid leukemia, n = 20). At the time of analysis, 90% of patients had died, with the longest follow-up since randomization 36 months. The combination of glasdegib and LDAC conferred superior overall survival (OS) versus LDAC alone; hazard ratio (HR) 0.495; (95% confidence interval [CI] 0.325–0.752); p = 0.0004; median OS was 8.3 versus 4.3 months. Improvement in OS was consistent across cytogenetic risk groups. In a post-hoc subgroup analysis, a survival trend with glasdegib + LDAC was observed in patients with de novo acute myeloid leukemia (HR 0.720; 95% CI 0.395–1.312; p = 0.14; median OS 6.6 vs 4.3 months) and secondary acute myeloid leukemia (HR 0.287; 95% CI 0.151–0.548; p < 0.0001; median OS 9.1 vs 4.1 months). The incidence of adverse events in the glasdegib + LDAC arm decreased after 90 days’ therapy: 83.7% versus 98.7% during the first 90 days. Glasdegib + LDAC versus LDAC alone continued to demonstrate superior OS in patients with acute myeloid leukemia; the clinical benefit with glasdegib + LDAC was particularly prominent in patients with secondary acute myeloid leukemia. ClinicalTrials.gov identifier: NCT01546038.Open Access funding enabled and organized by Projekt DEAL. This study was funded by Pfizer.Peer reviewe

Calculation of the critical energy release rate Gc of the cement line in cortical bone combining experimental tests and finite element models

[EN] In this work, a procedure is proposed to estimate the critical energy release rate Gc of the so-called cement line in cortical bone tissue. Due to the difficulty of direct experimental estimations, relevant elastic and toughness material properties at bone microscale have been inferred by correlating experimental tests and finite element simulations. In particular, three-point bending tests of ovine cortical bone samples have been performed and modeled by finite elements. The initiation and growth of microcracks in the tested samples are simulated through finite elements using a damage model based on a maximum principal strain criterion, showing a good correlation with the experimental results. It is observed that microcracks evolve mainly along the cement lines and through the interstitial material but without crossing osteons. The numerical model allows the calculation of the cement line critical energy release rate Gc by approximating its definition by finite differences. This way, it is possible to estimate this property poorly documented in the literature.The authors wish to thank the Ministerio de Economia y Competitividad for the support received in the framework of the project DPI2013-46641-R and to the Generalitat Valenciana, Programme PROMETEO 2016/007. The authors also thank Dr. Jose Luis Peris, from Instituto de Biomecanica de Valencia (IBV) and Carlos Tudela Desantes for their collaboration within the context of the project.Giner Maravilla, E.; Belda, R.; Arango-Villegas, C.; Vercher Martínez, A.; Tarancón Caro, JE.; Fuenmayor Fernández, FJ. (2017). Calculation of the critical energy release rate Gc of the cement line in cortical bone combining experimental tests and finite element models. Engineering Fracture Mechanics. 184:168-182. https://doi.org/10.1016/j.engfracmech.2017.08.026S16818218

Changes in white matter as determinant of global functional decline in older independent outpatients: three year follow-up of LADIS (leukoaraiosis and disability) study cohort

Objective To assess the impairment in daily living activities in older people with age related changes in white matter according to the severity of these changes

Integración social al contexto cultural de Lima Metropolitana

A raíz de la migración venezolana al Perú, se pretende abordar la experiencia personal de los migrantes venezolanos frente a su integración al contexto cultural de Lima Metropolitana, considerando su trayecto migratorio, proceso aculturativo, y el nuevo contexto sociocultural al que se enfrentan. Por ello, se busca describir la experiencia personal de los migrantes venezolanos sobre su integración social al contexto cultural de Lima Metropolitana, al igual que identificar su estilo aculturativo respecto a su integración social a este mismo contexto. Para ello, se utilizó un estudio cualitativo de alcance descriptivo y diseño fenomenológico. El muestreo realizado fue mixto, no probabilístico y por conveniencia. La muestra fue de 5 migrantes venezolanos entre las edades de 18 a 55 años, que han vivido en Lima Metropolitana por más de 2 años. Asimismo, las entrevistas realizadas permitieron profundizar en el proceso de integración social de los venezolanos al contexto cultural de Lima Metropolitana. Respecto a las conclusiones, indagamos sobre la experiencia personal de los migrantes venezolanos, quienes relataron su proceso de integración al contexto cultural de Lima Metropolitana. Al igual que el estilo aculturativo de integración, sus motivos migratorios fueron similares. Este segundo punto se correlaciona con la crisis política que atravesaba su país. Adicionalmente, destacó la fuerte discriminación de los limeños hacia los entrevistados debido a su nacionalidad venezolana. Como recomendación, se aconseja ahondar en la guía de entrevista planteada para conocer la situación de los evaluados y, así, obtener información más detallada acerca de su proceso migratorio y aculturativo

Agreement between the SCORE and D’Agostino Scales for the Classification of High Cardiovascular Risk in Sedentary Spanish Patients

Background: To evaluate agreement between cardiovascular risk in sedentary patients as estimated by the new Framingham-D’Agostino scale and by the SCORE chart, and to describe the patient characteristics associated with the observed disagreement between the scales. Design: A cross-sectional study was undertaken involving a systematic sample of 2,295 sedentary individuals between 40–65 years of age seen for any reason in 56 primary care offices. An estimation was made of the Pearson correlation coefficient and kappa statistic for the classification of high risk subjects (≥20% according to the Framingham-D’Agostino scale, and ≥5% according to SCORE). Polytomous logistic regression models were fitted to identify the variables associated with the discordance between the two scales. Results: The mean risk in males (35%) was 19.5% ± 13% with D’Agostino scale, and 3.2% ± 3.3% with SCORE. Among females, they were 8.1% ± 6.8% and 1.2% ± 2.2%, respectively. The correlation between the two scales was 0.874 in males (95% CI: 0.857–0.889) and 0.818 in females (95% CI: 0.800–0.834), while the kappa index was 0.50 in males (95% CI: 0.44%–0.56%) and 0.61 in females (95% CI: 0.52%–0.71%). The most frequent disagreement, characterized by high risk according to D’Agostino scale but not according to SCORE, was much more prevalent among males and proved more probable with increasing age and increased LDL-cholesterol, triglyceride and systolic blood pressure values, as well as among those who used antihypertensive drugs and smokers. Conclusions: The quantitative correlation between the two scales is very high. Patient categorization as corresponding to high risk generates disagreements, mainly among males, where agreement between the two classifications is only moderate