691 research outputs found
Double-nucleus elliptical MCG-01-12-005 in an X-ray emitting cluster of galaxies
The scenario of galaxy formation is believed to follow a structure that
builds up from the bottom, with large galaxies being formed by several merging
episodes of smaller ones. In this scenario a number of galaxies can be expected
to be seen in the merging phase, with their external regions already mixed,
while their nuclei, with stronger self-gravitation, are still recognizable as
such. During a photometric monitoring of AGNs in the field of a long-exposure
INTEGRAL pointing, we serendipitously found an elliptical galaxy in the center
of the X-ray cluster (EXO 0422-086) with two nuclei. We performed surface
photometry on our images and those of the SDSS archive and obtained slit
spectra of both nuclei. Aperture photometry of the two stellar-like nuclei
showed very similar colors in the SDSS image and in our Johnson BVRI images,
which is typical of an elliptical galaxy nucleus. The spectra of the nuclei
showed the typical absorption lines of an elliptical galaxy without appreciable
emission lines. The redshifts derived from each nucleus were equal and fully
consistent with the literature value (0.0397). We can therefore exclude the
possibility that one of the nuclei is a foreground star or a background AGN and
consider this elliptical galaxy as a bona fide example of a galaxy merger.Comment: 4 pages, 3 figures. Accepted on Astronomy and Astrophysic
Conditions, constraints and contracts: on the use of annotations for policy modeling.
Organisational policies express constraints on generation and processing of resources. However, application domains rely on transformation processes, which are in principle orthogonal to policy specifications and domain rules and policies may evolve in a non-synchronised way. In previous papers, we have proposed annotations as a flexible way to model aspects of some policy, and showed how they could be used to impose constraints on domain configurations, how to derive application conditions on transformations, and how to annotate complex patterns. We extend the approach by: allowing domain model elements to be annotated with collections of elements, which can be collectively applied to individual resources or collections thereof; proposing an original construction to solve the problem of annotations remaining orphan , when annotated resources are consumed; introducing a notion of contract, by which a policy imposes additional pre-conditions and post-conditions on rules for deriving new resources. We discuss a concrete case study of linguistic resources, annotated with information on the licenses under which they can be used. The annotation framework allows forms of reasoning such as identifying conflicts among licenses, enforcing the presence of licenses, or ruling out some modifications of a licence configuration
Stabilization of an elusive tautomer by metal coordination
The solid-state isolation of the different tautomers of a chemical comÂpound can be a challenging problem. In many cases, tautomers with an energy very close to the most stable one cannot be isolated (elusive tautomers). In this article, with reference to the 4-methyl-7-(pyrazin-2-yl)-2H-[1,2,4]triazolo[3,2-c][1,2,4]triazole ligand, for which the elusive 3H-tautomer has an energy only 1.4 kcal mol(−1) greater than the most stable 2H form, we show that metal comÂplexation is a sucÂcessful and reliable way for stabilizing the elusive tautoÂmer. We have preÂpared two comÂplexes of the neutral ligand with CuBr(2) and ZnBr(2), namely, aquaÂbromidoÂbisÂ[4-methyl-7-(pyrazin-2-yl)-3H-[1,2,4]triazolo[3,2-c][1,2,4]triazole]copper(II) bromide trihydrate, [CuBr(C(8)H(7)N(7))(2)(H(2)O)]Br·3H(2)O, and diÂbroÂmidoÂ[4-methyl-7-(pyrazin-2-yl)-2H-[1,2,4]triazolo[3,2-c][1,2,4]triazole][4-methyl-7-(pyrazin-2-yl)-3H-[1,2,4]triazolo[3,2-c][1,2,4]triÂazole]zinc(II) monohydrate, [ZnBr(2)(C(8)H(7)N(7))(2)]·H(2)O. The X-ray analysis shows that, in both cases, the elusive 3H-tautomer is present. The results of the crystallographic analysis of the two comÂplexes reflect the different coordination preferences of Cu(II) and Zn(II). The copper(II) comÂplex is homotautomeric as it only conÂtains the elusive 3H-tautomer of the ligand. The comÂplex can be described as octaÂhedral with tetraÂgonal distortion. Two 3H-triazolotriazole ligands are bis-chelated in the equatorial plane, while a water molÂecule and a bromide ion in elongated axial positions comÂplete the coordination environment. The zinc(II) comÂplex, on the other hand, is heterotautomeric and conÂtains two bromide ions and two monodentate ligand molÂecules, one in the 2H-tautomeric form and the other in the 3H-tautomeric form, both coordinated to the metal in tetraÂhedral geometry. The observation of mixed-tautomer comÂplexes is unprecedented for neutral ligands. The analysis of the X-ray molÂecular structures of the two comÂplexes allows the deduction of possible rules for a rational design of mixed-tautomer comÂplexes
Forest stand structure and coarse woody debris determine the biodiversity of beetle communities in Mediterranean mountain beech forests
Abstract The relationships between structural complexity, deadwood abundance, microhabitat type and species-diversity indicators are excellent tools to monitor biodiversity in forest ecosystems. In spite of their importance, correlations between structural traits and Coleoptera communities in Mediterranean mountain forests have only rarely been investigated. Consequently, the magnitude and direction of the relationships between forest traits and biodiversity indicators remain poorly understood. In this study, we analyzed whether biodiversity indices of saproxylic and non-saproxylic beetle communities could be influenced by stand structure, microhabitat type, and deadwood abundance in two protected beech forests located in the central and southern Apennines (namely Gran Sasso e Monti della Laga National Park, GSML, and Cilento, Vallo di Diano e Alburni National Park, CVDA). Standard measurements of forest structural traits and quantitative assessment of tree microhabitats and deadwood were carried out. Adult beetles were collected using window flight traps and emergence traps on decaying deadwood. The two beech forests were different in terms of both beetle communities and structural traits. A two-block partial least squares analysis 2B-PLS highlighted differences in biodiversity indices and structural traits between the two forest ecosystems. In GSML, we observed that biodiversity indices were positively correlated with the volume of coarse woody debris and the presence fungal infections, clefts into the sapwood, and woodpecker cavities, while more dominant beetle communities were found under denser canopy cover. In CVDA, Coleoptera abundance was positively correlated with the basal area and crown broken microhabitats. Our results point toward the relevance of ecological attributes in tracking changes in beetle biodiversity in specific forest contexts. In these protected Mediterranean mountain beech stands, in which the main forest management strategies have the primary objective of biodiversity conservation, we suggest to progressively increase the structural diversity and canopy dynamics, as well as the volume of coarse woody debris
Robotic double-loop reconstruction method following total gastrectomy
Minimally invasive surgery for gastric cancer is a challenge. The reconstructive time is a particular issue and researchers have adopted a large variety of solutions and produced heterogeneous data.
The reconstructive phase can be divided into two major categories based on the approach adopted: the execution of extracorporeal versus intracorporeal anastomosis. In turn, the surgical team can perform the latter with laparoscopic or robotic assistance. However, the question is, how should a robotic esophagojejunal anastomosis be performed after total gastrectomy?
Most articles in the literature have reported the execution of mechanical anastomoses [1] [2] [3] [4] [5] [6], especially with circular staplers via the creation of a manual purse-string around the anvil. Other solutions have described the use of the Orvil or the overlap technique. Only three authors have reported intracorporeal sutures with a completely robotic-sewn anastomosis [7] [8] [9].
A new robotic technique (the Parisi technique) was developed and adopted at St. Mary’s Hospital, Terni, Italy. A double-loop reconstruction method with an intracorporeal robot-sewn anastomosis is performe
L’usine, l’espace et la ville à Naples dans une perspective historique : installation, réemploi, délocalisation
Depuis l’Ancien Régime et jusqu’à sa récente désindustrialisation, la ville de Naples a été un territoire profondément marqué par ses activités de production. Le propos de cet article est de se pencher sur cette histoire et sur les empreintes laissées par celle-ci, afin d’aborder le problème du réemploi des friches industrielles. L’analyse cherche à déterminer comment cette partie de l’identité urbaine napolitaine a été valorisée, délaissée ou instrumentalisée dans le cadre d’enjeux politiques, économiques et sociaux divers et par des acteurs agissant selon des stratégies et des modes de pensée en évolution. Au final, l’histoire de la construction et de la conversion des espaces industriels napolitains aide à saisir, dans le temps long, quelques fondements et certaines transformations des rapports sociaux et des politiques urbanistiques dans l’Europe et dans la Méditerranée de l’Ancien Régime et de l’époque contemporaine.Since the Ancient Regime and until its recent deindustrialization, the city of Naples was a territory deeply marked by its manufacturing activities. This article seeks to explore this history and the remaining traces, in order to address the problem of reutilization of industrial brownfields. It seeks to determine how this part of the Neapolitan urban identity has been valorized, abandoned or instrumentalized in response to political, economic and social questions and to players as they react to the evolution in strategies and approaches. Finally, the history of the construction and conversion of Naples’ industrial areas will help us understand, for the long term, the basic elements and a number of transformations in social relationships and town planning policies in Europe and the Mediterranean under the Ancient Regime and in contemporary society
Naples. Un patrimoine portuaire entre mémoire et valorisation
Naples a été une étape très importante des études menées par Rachel Rodrigues-Malta sur les relations entre les villes et les ports et de son parcours professionnel. De 1994 à 2008, elle a réussi à construire un réseau extraordinaire de relations entre spécialistes et institutions locales et internationales, grâce auquel elle a démontré qu’il ne peut y avoir valorisation d’un espace portuaire délaissé sans médiation entre la nécessité de préserver la mémoire historique et les instances authentiques de renouvellement économique et social. L’auteur se penche sur certaines des questions abordées dans ces études en utilisant trois mots-clés : patrimoine, mémoire et valorisation.In terms of Rachel Rodrigues-Malta’s studies of interactions between cities and ports, Naples stands as a milestone in her professional career. From 1994 to 2008, Rachel managed to build up an extraordinary network of relationships between specialists and local and international institutions, with which she was able to demonstrate that an abandoned port area cannot be renovated without finding a balance between the need to preserve its historical heritage and the legitimate opportunities for ensuring economic and social renewal. The author reviews some of the issues raised in Rachel’s studies by focusing on three key words: heritage, memory and valorization.Napoli è stata una tappa molto importante degli studi di Rachel Rodrigues-Malta sulle relazioni tra città e porto e del suo percorso professionale. A partire dal 1994 e fino al 2008, è riuscita a costruire una straordinaria rete di relazioni tra specialisti e tra istituzioni scientifiche locali e internazionali, attraverso la quale ha potuto dimostrare che non vi può essere valorizzazione di uno spazio portuale dismesso senza una corretta mediazione tra le esigenze di conservazione della memoria storica e autentiche istanze di rinnovamento economico e sociale. L’autore si sofferma su alcune delle questioni affrontate da Rachel in questi studi attraverso l’individuazione di tre parole chiave : patrimonio, memoria e valorizzazione
Conditions, constraints and contracts: On the use of annotations for policy modeling
Organisational policies express constraints on generation and processing of resources. Application domains, however, rely on transformation processes, which are in principle orthogonal to policy specifications, so that domain rules and policies may evolve in a non-synchronised way. In previous papers, we proposed annotations as a flexible way to model aspects of some kinds of policy. Annotations could be used to impose constraints on domain configurations, and we showed how to derive application conditions on transformations, and how to annotate complex patterns. We extend the approach here in different directions: we allow domain model elements (individual resources or collections thereof) to be annotated with collections of elements; we propose an original construction to solve the problem of orphan annotations, when annotated resources are consumed; we introduce a notion of contract, used by a policy to impose additional pre-conditions and postconditions on rules for deriving new resources. We also show how contracts for refined rules can be derived from contract schemes defined on some rule kernel. We discuss a concrete case study of linguistic resources, annotated with information on the licenses under which they can be used. The annotation framework allows forms of reasoning such as identifying conflicts among licenses, enforcing the presence of licenses, or ruling out some modifications of a licence configuration
Novel strategies of adoptive immunotherapy: How natural killer cells may change the treatment of elderly patients with acute myeloblastic leukemia
Although many attempts have been made to identify novel molecular-targeted therapies for patients with acute myeloid leukemia, their translation into the clinic have had limited impact. In particular, the question of effective and curative treatments for elderly patients, who are not eligible for stem cell transplantation, remains an unmet medical need. To answer this question, a wide range of immunologic therapeutic strategies, mostly T cell based, have been proposed and investigated. At present, however, the clinical results have been largely unsatisfactory. Natural killer cells have recently been used as a means of adoptive immunotherapy with promising clinical results. On the basis of recent clinical reports and moving from the basic immunobiology of natural killer cells, here we discuss some open issues in the clinical translation of natural killer-based adoptive immunotherapy for the management of elderly patients with acute myeloid leukemia
New totally intracorporeal reconstructive approach after robotic total gastrectomy. Technical details and short-term outcomes
AIM:
To show outcomes of our series of patients that underwent a total gastrectomy with a robotic approach and highlight the technical details of a proposed solution for the reconstruction phase.
METHODS:
Data of gastrectomies performed from May 2014 to October 2016, were extracted and analyzed. Basic characteristics of patients, surgical and clinical outcomes were reported. The technique for reconstruction (Parisi Technique) consists on a loop of bowel shifted up antecolic to directly perform the esophago-enteric anastomosis followed by a second loop, measured up to 40 cm starting from the esojejunostomy, fixed to the biliary limb to create an enteroenteric anastomosis. The continuity between the two anastomoses is interrupted just firing a linear stapler, so obtaining the Roux-en-Y by avoiding to interrupt the mesentery.
RESULTS:
Fifty-five patients were considered in the present analysis. Estimated blood loss was 126.55 ± 73 mL, no conversions to open surgery occurred, R0 resections were obtained in all cases. Hospital stay was 5 (3-17) d, no anastomotic leakage occurred. Overall, a fast functional recovery was shown with a median of 3 (3-6) d in starting a solid diet.
CONCLUSION:
Robotic surgery and the adoption of a tailored reconstruction technique have increased the feasibility and safety of a minimally invasive approach for total gastrectomy. The present series of patients shows its implementation in a western center with satisfying short-term outcomes
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