The double population of Chamaeleon I detected by Gaia DR2

Context. Chamaeleon I represents an ideal laboratory to study the cluster formation in a low-mass environment. Recently, two sub clusters spatially located in the northern and southern parts of Chamaeleon I were found with different ages and radial velocities. Aims. In this letter we report new insights into the structural properties, age, and distance of Chamaeleon I based on the astrometric parameters from Gaia data-release 2 (DR2). Methods. We identified 140 sources with a reliable counterpart in the Gaia DR2 archive. We determined the median distance of the cluster using Gaia parallaxes and fitted the distribution of parallaxes and proper motions assuming the presence of two clusters. We derived the probability of each single source of belonging to the northern or southern sub-clusters, and compared the HR diagram of the most probable members to pre-main sequences isochrones. Results. The median distance of Chamaeleon I is ~190 pc. This is about 20 pc larger than the value commonly adopted in the literature. From a Kolmogorov-Smirnov test of the parallaxes and proper-motion distributions we conclude that the northern and southern clusters do not belong to the same parent population. The northern population has a distance dN = 192.7+/-0.4 pc, while the southern one dS = 186.5+/-0.7 pc. The two sub-clusters appear coeval, at variance with literature results, and most of the sources are younger than 3 Myr. The northern cluster is more elongated and extends towards the southern direction partially overlapping with the more compact cluster located in the south. A hint of a relative rotation between the two sub-clusters is also found.Comment: Letter accepted by A&

Lo scavo della Chiesa di Santa Maria Degli Angeli alla Gancia: indicatori archeologici della prima età islamica a Palermo

Lo scavo in occasione del restauro della chiesa di Santa Maria degli Angeli alla Gancia a Palermo ha permesso di recuperare alcune stratigrafie affidabili relative alla prima età islamica a Palermo. Lo studio della ceramica ha restituito una serie di indicatori cronologici per il IX-X secolo nonché di proporre nuove cronologie per alcune classi di materiali. Relativamente alla storia della città questo scavo ha aggiunto alcune note importanti che riguardano il porto e la cittadella e mirale la al-Halisah

Curso de atualização sobre Tristeza Parasitaria Bovina (TPB).

A tristeza Parasitária Bovina (TPB) é um complexo de doenças que no nosso meio é causado principalmente por Babesiose e Anaplasmose, além de envolver a presença do carrapato Boophilus microplus. Este conjunto de enfermidade é uma das principais senão a maior preocupação dos produtores de bovinos da Região Sul do Brasil, pois traz importantes prejuízos econômicos por mortalidade e morbidade. Portanto é oportuno trazer o assunto à discussão para a atualização do conhecimento de técnicos e produtores rurais.bitstream/item/110567/1/CURSO-DE-ATUALIZACAO-SOBRE.pd

Behavior of N-Doped TiO2 and N-Doped ZnO in Photocatalytic Azo Dye Degradation under UV and Visible Light Irradiation: A Preliminary Investigation

Abstract: N-doped TiO2 (N-TiO2) and N-doped ZnO (N-ZnO) were synthesized utilizing ammonia as a dopant source. The chemico-physical characteristics of synthesized samples were studied by Raman spectroscopy, X-ray diffraction, SEM analysis, N2 adsorption–desorption at −196 ◦C, and diffuse reflectance spectroscopy. Compared to undoped samples, the introduction of nitrogen in the semiconductor lattice resulted in a shift of band-gap energy to a lower value: 3.0 eV for N-ZnO and 2.35 eV for N-TiO2. The photocatalysts were tested for the degradation of Eriochrome Black T (EBT), which was selected as a model azo dye. Both N-doped semiconductors evidenced an improvement in photocatalytic activity under visible light irradiation (62% and 20% EBT discoloration for N-TiO2 and N-ZnO, respectively) in comparison with the undoped samples, which were inactive in the presence of visible light. Different behavior was observed under UV irradiation. Whereas N-TiO2 was more photoactive than commercial undoped TiO2, the introduction of nitrogen in ZnO wurtzite resulted in a drastic reduction in photocatalytic activity, with only 45% EBT discoloration compared to total color removal obtained with the commercial ZnO sample, suggesting intrinsic limitations for doping of this class of semiconductors

Ethical Consistency and Experience: An Attempt to Influence Researcher Attitudes Toward Questionable Research Practices Through Reading Prompts

Over the past couple of decades, the apparent widespread occurrence of Questionable Research Practices (QRPs) in scientific research has been widely discussed in the research ethics literature as a source of concern. Various ways of reducing their use have been proposed and implemented, ranging from improved training and incentives for adopting best practices to systematic reforms. This article reports on the results of two studies that investigated the efficacy of simple, psychological interventions aimed at changing researcher attitudes toward QRPs. While the interventions did not significantly modify researchers’ reactions to QRPs, they showed differential efficacy depending on scientists’ experience, suggesting complexities in researcher psychology and the ethics of QRPs that merit further study

Intrapancreatic accessory spleen false positive to 68Ga-Dotatoc: case report and literature review

Background: Intrapancreatic accessory spleen (IPAS) is an uncommon finding of pancreatic mass. Differential diagnosis with pancreatic tumor, especially with non-functional neuroendocrine tumor (NF-NET), may be very hard and sometimes it entails unnecessary surgery. A combination of CT scan, MRI, and nuclear medicine can confirm the diagnosis of IPAS. 68-Ga-Dotatoc PET/CT is the gold standard in NET diagnosis and it can allow to distinguish between IPAS and NET. Case presentation: A 69-year-old man was admitted to our hospital for an incidental nodule in the tail of the pancreas with focal uptake of 68-Ga-dotatate at PET/CT. NET was suspected and open distal splenopancreatectomy was performed. Pathologic examination revealed an IPAS. Conclusion: This is the second IPAS case in which a positive 68Ga-Dotatoc uptake led to a false diagnosis of pancreatic NET. Here is a proposal of a literature review

High resolution nuclear magnetic resonance spectroscopy (NMR) studies on meat components: potentialities and prospects

In recent years, increasing application of nuclear magnetic resonance (NMR) spectroscopy in the study of the agricultur- al food products has been remarked, thanks to the advantages of this technique over other conventional analytical tech- niques. This preliminary work presents, for the first time, the application of an innovative NMR technique, the proton high resolution magic angle spinning (1H HR-MAS), for studying meat features. It stresses that this method makes it pos- sible to acquire qualitative and quantitative information about chemical composition, both quickly and without any par- ticular preparation of the sample to be analysed. Finally, the study highlights the potentiality of this method in defining the origin of meat and the possibility of identifying meat adulteration

Modelling of masonry arches strengthened at extrados with FRCM

Masonry arches are amongst the most fascinating structures of the World's historical and architectural heritage. Their vulnerability to earthquakes pointed out the necessity of their preservation. Fiber Reinforced Cementitious Mortar (FRCM) composites have been recently used as a more sustainable alternative to FRPs in the strengthening of masonry structures, since they can overcome the limits FRP show as strengthening systems: poor behavior to high temperature, delamination with significant loss of material at the bonded surface, lack of vapor permeability, impossibility of application on humid surfaces, incompatibility of resins with masonry, high cost and reduced reversibility of the installation. These aspects have a critical relevance in the case of historical structures, whose features have to be preserved, and motivate researches about the use of FRCM on masonry structures, from both experimental and analytical points of view. In this paper, the results of numerical analyses performed on arches unstrengthened and strengthened at the extrados with PBO-FRCM composites are presented, taking as reference the experimental tests published in [1] and [2]. The aim of this research is to further investigate the benefits that the use of FRCM composites have on the mechanical performance of masonry. The used model, implemented in the finite element code DIANA FEA, succeeded in reproducing the mechanical behavior of the considered arches in terms of collapse mechanism, load carrying capacity and ductility.- (undefined

Low cost system for visualization and exhibition of pottery finds in archeological museums

The objective of this project is to build a low-cost system for surveying, modeling, prototyping and interactive visualizing aimed at the enhancement of islamic pottery finds of X – XI centuries. The system will allow various applications: the creation of systems for displaying artifacts from the museum alongside the exhibition, the virtual view of restorations from fragments, including AR and VR, the physical reconstruction of the original form using 3D printer to show the pieces in their entirety, as well as the construction of interactive virtual archives to be made available to scholars and visitors