239 research outputs found
Oriented right-angled Artin pro- groups and maximal pro- Galois groups
For a prime number we introduce and study oriented right-angled Artin
pro- groups (oriented pro- RAAGs for short)
associated to a finite oriented graph and a continuous group
homomorphism . We show
that an oriented pro- RAAG is a Bloch-Kato
pro- group if, and only if,
is an oriented pro- group
of elementary type generalizing a recent result of I. Snopche and P. Zalesskii.
Here
denotes the canonical -orientation on . We invest
some effort in order to show that oriented right-angled Artin pro- groups
share many properties with right-angled Artin pro--groups or even
discrete RAAG's, e.g., if is a specially oriented chordal graph, then
is coherent, generalizing a result of C. Droms. Moreover,
in this case has the
Positselski-Bogomolov property generalizing a result of H. Servatius, C. Droms
and B. Servatius for discrete RAAG's. If is a specially oriented
chordal graph and in case that
, then generalizing a well known result of M.
Salvetti.Comment: The differences between the 1st version (Apr'23) and the 2nd are:
correction of a couple of minor misprints, dedication to the memory of
Avinoam Man
9-Anthraldehyde oxime: a synthetic tool for variable applications
Abstract
Oximes are one of the most important and prolific functional groups in organic chemistry; among them, 9-anthraldehyde oxime represents a valuable example both from the preparative side and the synthetic applications. There are many strategies to prepare 9-anthraldehyde oxime from different functional groups that were summarized in the present review, focusing on the most recent and innovative. The main synthetic applications of 9-anthraldehyde oxime are presented and thoroughly discussed, focusing on the most recent and innovative synthetic strategies.
Graphic abstrac
Clinical Characteristics and Prognosis of Incidentally Detected Lung Cancers
Objective. To evaluate clinical characteristics and outcomes in incidentally detected lung cancer and in symptomatic lung cancer. Material and Methods. We designed a retrospective study including all patients undergoing pulmonary resection with a curative intention for NSCLC. They were classified into two groups according to the presence or absence of cancer-related symptoms at diagnosis in asymptomatic (ASX)—incidental diagnosis—or symptomatic. Results. Of the 593 patients, 320 (53.9%) were ASX. In 71.8% of these, diagnosis was made by chest X-ray. Patients in the ASX group were older (P=0.007), had a higher prevalence of previous malignancy (P=0.002), presented as a solitary nodule more frequently (P<0.001), and were more likely to have earlier-stage disease and smaller cancers (P=0.0001). A higher prevalence of incidental detection was observed in the last ten years (P=0.008). Overall 5-year survival was higher for ASX (P=0.001). Median survival times in pathological stages IIIB-IV were not significantly different. Conclusion. Incidental finding of NSCLC is not uncommon even among nonsmokers. It occurred frequently in smokers and in those with history of previous malignancy. Mortality of incidental diagnosis group was lower, but the better survival was related to the greater number of patients with earlier-stage disease
Obscuring clouds playing hide-and-seek in the Active Nucleus H0557-385
This paper reports on two XMM-Newton observations of the Seyfert 1 Galaxy
H0557-385 obtained in 2006, which show the source at an historical low flux
state, more than a factor of 10 lower than a previous XMM-Newton look in 2002.
The low flux spectrum presents a strong Fe Kalpha line associated to a Compton
reflection continuum. An additional spectral line around 6.6 keV is required to
fit Kalpha emission from Fe XXV. The spectral curvature below 6 keV implies
obscuration by neutral gas with a column density of 8*10^{23}cm^{-2} partially
covering the primary emission, which still contributes for a few percent of the
soft X-ray emission. Absorption by ionised material on the line of sight is
required to fit the deep trough below 1 keV. The comparison of the two spectral
states shows that the flux transition is to be ascribed entirely to intervening
line-of-sight clouds with high column density.Comment: 5 pages, accepted for publication on MNRAS Letter
4U 1344-60: a bright intermediate Seyfert galaxy at z=0.012 with a relativistic Fe Kalpha emission line
We present analysis of the optical and X-ray spectra of the low Galactic
latitude bright (F(2-10) = 3.6 10^{-11} erg/cm2/s) source 4U 1344-60. On the
basis of the optical data we propose to classify 4U 1344-60 as an intermediate
type Seyfert galaxy and we measure a value of z=0.012+/-0.001 for its redshift.
From the XMM-Newton observation we find that the overall X-ray spectral shape
of 4U 1344-60 is complex and can be described by a power-law continuum (Gamma ~
1.55) obscured by two neutral absorption components (Nh(f) ~ 10^{22} cm^{-2}
and Nh(p) ~ 4 10^{22} cm^{-2}), the latter covering only the ~50% of the
primary X-ray source. The X-ray data therefore lend support to our
classification of 4U 1344-60. It exhibits a broad and skewed Fe Kalpha line at
6.4 keV, which suggests the existence of an accretion disk that is able to
reprocess the primary continuum down to a few gravitational radii. Such a line
represents one of the clearest examples of a relativistic line observed by
XMM-Newton so far. Our analysis has also revealed the marginal presence of two
narrow line-like emission features at ~4.9 and ~5.2 keV.Comment: Accepted for publication in Astronomy & Astrophysic
Palliative care in interstitial lung disease: living well
Progressive fibrotic interstitial lung diseases (ILDs) are characterised by major reductions in quality of life and survival and have similarities to certain malignancies. However, palliative care expertise is conspicuously inaccessible to many patients with ILD. Unmet patient and caregiver needs include effective pharmacological and psychosocial interventions to improve quality of life throughout the disease course, sensitive advanced care planning, and timely patient-centred end-of-life care. The incorrect perception that palliative care is synonymous with end-of-life care, with no role earlier in the course of ILD, has created a culture of neglect. Interventions that aim to improve life expectancy are often prioritised without rigorous assessment of the individual's health and psychosocial needs, thereby inadvertently reducing quality of life. As in malignant disorders, radical interventions to slow disease progression and palliative measures to improve quality of life should both be prioritised. Efficient patient-centred models of palliative care must be validated, taking into account religious and cultural differences, as well as variability of resources. Effective implementation of palliative care for ILD will require multidisciplinary participation from clinicians, specialist nurses, psychologists, social workers, and, in some countries, non-governmental faith and community-based organisations with access to palliative care expertise
Machine learning system to guide teacher reflection on behavior management skills
This paper presents a classroom behavior management skills classification system based on machine learning to assist teachers to develop their classroom behavior management skills through guided reflection. Such a system would enable more cost-effective application of demonstrably successful approaches to having expert observers identify suggestible moments for reflection. The proposed system accepts input videos from teachers and provides classification results of specific behavior management skills that occurred on those videos. The classification results, together with relevant additional information will be provided to teachers as suggestions for reflection. The proposed approach relies on deep learning and computer vision techniques to provide the classification results. Additionally, the proposed approach has been evaluated on videos containing four of the essential teaching skills and has achieved an average F1-score of 84.75%
U-PHOS Project: Development of a Large Diameter Pulsating Heat Pipe Experiment on board REXUS 22
U-PHOS Project aims to analyse and characterise the behaviour of a large diameter Pulsating Heat Pipe (PHP) on board REXUS 22 sounding rocket. A PHP is a passive thermal control device consisting of a serpentine capillary tube, evacuated, partially filled with a working fluid and finally sealed. In this configuration, the liquid and vapour phases are randomly distributed in the form of liquid slugs and vapour plugs. The heat is efficiently transported by means of the self-sustained oscillatory fluid motion driven by the phase change phenomena. On ground conditions, a small diameter is required in order to obtain a confined slug flow regime. In milli-gravity conditions, buoyancy forces become less intense and the PHP diameter may be increased still maintaining the slug/plug flow configuration typical of the PHP operation. Consequently, the PHP heat power capability may be increased too. U-PHOS aims at proving that a Large Diameter PHP effectively works in milli-g conditions by characterizing its thermal response during a sounding rocket flight. The actual PHP tube is made of aluminum (3 mm inner diameter, filled with FC-72), heated at the evaporator by a compact electrical resistance, cooled at the condenser by a Phase Change Material (PCM) embedded in a metallic foam. The tube wall temperatures are recorded by means of Fibre Bragg Grating (FBG) sensors; the local fluid pressure is acquired by means of a pressure transducer. The present work intends to report the actual status of the project, focusing in particular on the experiment improvements with respect to the previous campaign
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