27 research outputs found
The High Mass X-ray Binaries in star-forming galaxies
The high mass X-ray binaries (HMXBs) provide an exciting framework to
investigate the evolution of massive stars and the processes behind binary
evolution. HMXBs have shown to be good tracers of recent star formation in
galaxies and might be important feedback sources at early stages of the
Universe. Furthermore, HMXBs are likely the progenitors of gravitational wave
sources (BH--BH or BH--NS binaries that may merge producing gravitational
waves). In this work, we investigate the nature and properties of HMXB
population in star-forming galaxies. We combine the results from the population
synthesis model MOBSE (Giacobbo et al. 2018) together with galaxy catalogs from
EAGLE simulation (Schaye et al. 2015). Therefore, this method describes the
HMXBs within their host galaxies in a self-consistent way. We compute the X-ray
luminosity function (XLF) of HMXBs in star-forming galaxies, showing that this
methodology matches the main features of the observed XLF.Comment: 4 pages, 2 figures. To appear in Proc. IAUS 346: High-mass X-ray
binaries: illuminating the passage from massive binaries to merging compact
object
Characteristics of the Mesophotic Megabenthic Assemblages of the Vercelli Seamount (North Tyrrhenian Sea)
The biodiversity of the megabenthic assemblages of the mesophotic zone of a Tyrrhenian seamount (Vercelli Seamount) is described using Remotely Operated Vehicle (ROV) video imaging from 100 m depth to the top of the mount around 61 m depth. This pinnacle hosts a rich coralligenous community characterized by three different assemblages: (i) the top shows a dense covering of the kelp Laminaria rodriguezii; (ii) the southern side biocoenosis is mainly dominated by the octocorals Paramuricea clavata and Eunicella cavolinii; while (iii) the northern side of the seamount assemblage is colonized by active filter-feeding organisms such as sponges (sometimes covering 100% of the surface) with numerous colonies of the ascidian Diazona violacea, and the polychaete Sabella pavonina. This study highlights, also for a Mediterranean seamount, the potential role of an isolated rocky peak penetrating the euphotic zone, to work as an aggregating structure, hosting abundant benthic communities dominated by suspension feeders, whose distribution may vary in accordance to the geomorphology of the area and the different local hydrodynamic conditions
Adjuvant capecitabine in triple negative breast cancer patients with residual disease after neoadjuvant treatment: real-world evidence from CaRe, a multicentric, observational study
Background: In triple negative breast cancer patients treated with neoadjuvant chemotherapy, residual disease at surgery is the most relevant unfavorable prognostic factor. Current guidelines consider the use of adjuvant capecitabine, based on the results of the randomized CREATE-X study, carried out in Asian patients and including a small subset of triple negative tumors. Thus far, evidence on Caucasian patients is limited, and no real-world data are available. Methods: We carried out a multicenter, observational study, involving 44 oncologic centres. Triple negative breast cancer patients with residual disease, treated with adjuvant capecitabine from January 2017 through June 2021, were recruited. We primarily focused on treatment tolerability, with toxicity being reported as potential cause of treatment discontinuation. Secondarily, we assessed effectiveness in the overall study population and in a subset having a minimum follow-up of 2 years. Results: Overall, 270 patients were retrospectively identified. The 50.4% of the patients had residual node positive disease, 7.8% and 81.9% had large or G3 residual tumor, respectively, and 80.4% a Ki-67 >20%. Toxicity-related treatment discontinuation was observed only in 10.4% of the patients. In the whole population, at a median follow-up of 15 months, 2-year disease-free survival was 62%, 2 and 3-year overall survival 84.0% and 76.2%, respectively. In 129 patients with a median follow-up of 25 months, 2-year disease-free survival was 43.4%, 2 and 3-year overall survival 78.0% and 70.8%, respectively. Six or more cycles of capecitabine were associated with more favourable outcomes compared with less than six cycles. Conclusion: The CaRe study shows an unexpectedly good tolerance of adjuvant capecitabine in a real-world setting, although effectiveness appears to be lower than that observed in the CREATE-X study. Methodological differences between the two studies impose significant limits to comparability concerning effectiveness, and strongly invite further research
Patterns of Diversity in Soft-Bodied Meiofauna: Dispersal Ability and Body Size Matter
Background: Biogeographical and macroecological principles are derived from patterns of distribution in large organisms, whereas microscopic ones have often been considered uninteresting, because of their supposed wide distribution. Here, after reporting the results of an intensive faunistic survey of marine microscopic animals (meiofauna) in Northern Sardinia, we test for the effect of body size, dispersal ability, and habitat features on the patterns of distribution of several groups.Methodology/Principal Findings: As a dataset we use the results of a workshop held at La Maddalena (Sardinia, Italy) in September 2010, aimed at studying selected taxa of soft-bodied meiofauna (Acoela, Annelida, Gastrotricha, Nemertodermatida, Platyhelminthes and Rotifera), in conjunction with data on the same taxa obtained during a previous workshop hosted at Tjärnö (Western Sweden) in September 2007. Using linear mixed effects models and model averaging while accounting for sampling bias and potential pseudoreplication, we found evidence that: (1) meiofaunal groups with more restricted distribution are the ones with low dispersal potential; (2) meiofaunal groups with higher probability of finding new species for science are the ones with low dispersal potential; (3) the proportion of the global species pool of each meiofaunal group present in each area at the regional scale is negatively related to body size, and positively related to their occurrence in the endobenthic habitat.Conclusion/Significance: Our macroecological analysis of meiofauna, in the framework of the ubiquity hypothesis for microscopic organisms, indicates that not only body size but mostly dispersal ability and also occurrence in the endobenthic habitat are important correlates of diversity for these understudied animals, with different importance at different spatial scales. Furthermore, since the Western Mediterranean is one of the best-studied areas in the world, the large number of undescribed species (37%) highlights that the census of marine meiofauna is still very far from being complete
Noncontact Mapping of Left Ventricle during CRT Implant
Introduction: Not all candidates for cardiac resynchronization therapy (CRT) are responders at followup.
Echocardiographic parameters of dyssynchrony do not predict the response. Analysis of electrical
properties of left ventricle (LV) by noncontact mapping (NCM) could be useful to better identify candidates
for CRT.
Methods and Results: We studied nine consecutive patients undergoing CRT. An NCM was positioned
in the LV via atrial transeptal puncture. LV activation was recorded during sinus rhythm (SR), pacing
from RV, from different LV epicardial locations, and in biventricular (BIV) pacing. The corresponding
invasive pressure was determined. Heparin, administered during NCM, was reversed and CRT implant
was completed. An offline analysis of the data was performed in order to measure transeptal and total LV
activation time, to evaluate the site of earliest and latest LV activation, and the pattern of activation.
No complications occurred. Mean time of total NCM procedures was 24 ± 7 minutes. During SR, RV,
LV, and BIV pacing, respectively, a “U”-shaped LV activation pattern was found in three, seven, four, and
and two patients; mean LV activation time was 58.1 ± 7.0, 81.7 ± 15.8, 71.1 ± 12.4, and 65.6 ± 7.7ms; and
mean systolic LV peak pressure was 114 ± 21, 97 ± 18, 103 ± 17 and 110 ± 15 mmHg, respectively. LV
activation was influenced by a slow conduction area at the pacing site and by the duration of transeptal
time.
Conclusion: An NCM during CRT is safe and feasible. It provides an additional information on electrical
activation in SR and in various modality of pacing. Further studies with larger populations are needed in
order to correlate electrical to clinical outcomes. (PACE 2010; 74–84
I MODELLI DEL CLIMA ALLA FRONTIERA DELLA SCIENZA E DELLA TECNOLOGIA
Lo studio del clima si basa su dati e osservazioni, oggi disponibili in quantità e qualità inimmaginabile fino a pochi anni fa. Tuttavia, per ottenere “previsioni climatiche” (o meglio “proiezioni” visto il carattere statistico del problema), è necessario utilizzare modelli matematici che descrivano, al meglio delle nostre conoscenze, il funzionamento del sistema climatico. Questi modelli, per la loro complessità, richiedono enormi risorse di calcolo e continua innovazione scientifica, tecnologica e informatica nella descrizione dei processi e nella loro implementazione numerica