813 research outputs found

    Calibration and signal reconstruction in the ATLAS Tile Hadronic calorimeter

    Get PDF
    International audienceTileCal is the barrel hadronic calorimeter of the ATLAS experiment at LHC/CERN, made of steel and scintillating tiles and read out by optical fibers and photomultiplier tubes. It provides measurements for hadrons, jets and missing transverse energy. The TileCal calibration procedures rely on the performance of dedicated calibration systems: - calibration of the full signal read-out path with movable radioactive 137Cs gamma source; - monitoring of the Photomultiplier tube gains with the laser system; - calibration of the front-end electronic gains with the charge injection system. In this talk we will describe the energy and time calibration procedures used in TileCal to establish the reference detector response and synchronization. We will also discuss the calibration systems performance and the corresponding uncertainties to the energy and timing measurements

    Il progetto “ceraNEApolis”: un sistema informativo cartografico delle produzioni ceramiche a Neapolis (IV a.C.-VII d.C.)

    Get PDF
    In the last few decades, urban archaeology in Naples has contributed to outline the history of the city. The discovery of a great amount of pottery gave information about the daily life of ancient Naples. It was therefore decided to draw up a thematic archaeological map of the ceramics finds to reconstruct their production and distribution from the 4th century B.C. to the 7th century A.D. The project ceraNEApolis consists of a pottery map linked to a bibliographic database, which will be made available online: a working tool for experts, useful to outline the cultural city stratification and to understand the Neapolitan archaeological sites through the material. It is useful in defining the topography of production (workshop, raw materials, and resources), distribution (communication routes, harbour, market), uses and consumption patterns (house, habitat, sacred areas, burials) in the city, even if lacking monumental evidence. It contributes to the reconstruction and analysis of the cultural and urban landscape, taking into account the geomorphological elements and the data contexts even in diachronic and transversal multi-disciplinary perspective. The analysis of some significant cases shows its validity also for potential alternative fruition. The integration of virtual reality systems is a possible extension also for the knowledge, enhancement, communication and use of cultural heritage

    Microglia Acquire Distinct Activation Profiles Depending on the Degree of α-Synuclein Neuropathology in a rAAV Based Model of Parkinson's Disease

    Get PDF
    Post-mortem analysis of brains from Parkinson's disease (PD) patients strongly supports microglia activation and adaptive immunity as factors contributing to disease progression. Such responses may be triggered by α-synuclein (α-syn), which is known to be the main constituent of the aggregated proteins found in Lewy bodies in the brains of PD patients. To investigate this we used a recombinant viral vector to express human α-syn in rat midbrain at levels that induced neuronal pathology either in the absence or the presence of dopaminergic cell death, thereby mimicking early or late stages of the disease. Microglia activation was assessed by stereological quantification of Mac1+ cells, as well as the expression patterns of CD68 and MCH II. In our study, when α-syn induced neuronal pathology but not cell death, a fast transient increase in microglia cell numbers resulted in the long-term induction of MHC II+ microglia, denoting antigen-presenting ability. On the other hand, when α-syn induced both neuronal pathology and cell death, there was a delayed increase in microglia cell numbers, which correlated with long-lasting CD68 expression and a morphology reminiscent of peripheral macrophages. In addition T-lymphocyte infiltration, as judged by the presence of CD4+ and CD8+ cells, showed distinct kinetics depending on the degree of neurodegeneration, and was significantly higher when cell death occurred. We have thus for the first time shown that the microglial response differs depending on whether α-syn expression results on cell death or not, suggesting that microglia may play different roles during disease progression. Furthermore, our data suggest that the microglial response is modulated by early events related to α-syn expression in substantia nigra and persists at the long term

    Integrating gender expertise into the Canadian Armed Forces: challenges for change agents and culture change

    Get PDF
    IntroductionGender Advisors (GENADs) have played a key role in the efforts of military organizations worldwide to integrate gender perspectives, and culture change, within the defence and security context. Military organizations, however, continue to face challenges in regard to diversity and inclusion, including limited representation of women and other diverse groups who do not fit the white male, masculine stereotype, and subtle and overt expressions of prejudice and stigma towards under-represented and marginalized groups. In such an organizational context, the integration of gender perspectives has faced challenges, and transformative culture change has remained elusive. In particular, the experience of GENADs suggests that there may be unique challenges to serving as “gender experts” within military organizations. This paper, therefore, examines the lived experience of GENADs within the context of military organizations, as illustrated by GENADs in the Canadian Armed Forces.MethodsWe consider two qualitative studies on the lived experience of GENADs and focus on the shared theme of legitimacy of gender expertise at both individual and systemic levels.ResultsThis analysis highlights challenges that gendered power relations may pose for GENADs as individual change agents, and for systemic, transformative culture change, within existing military organizations, while reaffirming the importance of understanding the lived experience of GENADs in their pursuit of more equitable institutional and operational outcomes.ConclusionUsing social-psychological theories of tokenism, we consider more broadly what it means to be the gender person within masculinized military organizations and conclude with reflections on the potential contours of transformative culture change within the military context

    Development of a novel, windowless, amorphous selenium based photodetector for use in liquid noble detectors

    Full text link
    Detection of the vacuum ultraviolet (VUV) scintillation light produced by liquid noble elements is a central challenge in order to fully exploit the available timing, topological, and calorimetric information in detectors leveraging these media. In this paper, we characterize a novel, windowless amorphous selenium based photodetector with direct sensitivity to VUV light. We present here the manufacturing and experimental setup used to operate this detector at low transport electric fields (2.7-5.2 V/μ\mum) and across a wide range of temperatures (77K-290K). This work shows that the first proof-of-principle device windowless amorphous selenium is robust under cryogenic conditions, responsive to VUV light at cryogenic temperatures, and preserves argon purity. These findings motivate a continued exploration of amorphous selenium devices for simultaneous detection of scintillation light and ionization charge in noble element detectors

    Cancer drug related cardiotoxicity during breast cancer treatment

    Get PDF
    Introduction: Breast cancer (BC) is the most common cancer in women. Although therapeutic armamentarium like chemotherapy, endocrine and target agents have increased survival, cardiovascular side effects have been observed. A comprehensive risk assessment, early detection and management of cardiac adverse events is therefore needed. Areas covered: In this review we focus on cardiotoxicity data deriving from Phase III randomized trials, systematic reviews and meta-analysis in BC patients. We provide insight into advances that have been made in the molecular mechanisms, clinical presentation and management of such adverse event. Expert opinion: Despite the large number of data from Phase III trials about cardiac events incidence, there are poor evidences for detection, monitoring and management of cardiotoxicity during BC treatment. Future cardiotoxicity-oriented clinical cancer research can help to predict the risk of cardiac adverse events and improve patients’ outcome. Multidisciplinary approach as well as integration of blood biomarkers with imaging will be desirable

    Development of the (d,n) proton-transfer reaction in inverse kinematics for structure studies

    Get PDF
    Transfer reactions have provided exciting opportunities to study the structure of exotic nuclei and are often used to inform studies relating to nucleosynthesis and applications. In order to benefit from these reactions and their application to rare ion beams (RIBs) it is necessary to develop the tools and techniques to perform and analyze the data from reactions performed in inverse kinematics, that is with targets of light nuclei and heavier beams. We are continuing to expand the transfer reaction toolbox in preparation for the next generation of facilities, such as the Facility for Rare Ion Beams (FRIB), which is scheduled for completion in 2022. An important step in this process is to perform the (d,n) reaction in inverse kinematics, with analyses that include Q-value spectra and differential cross sections. In this way, proton-transfer reactions can be placed on the same level as the more commonly used neutron-transfer reactions, such as (d,p), (9Be,8Be), and (13C,12C). Here we present an overview of the techniques used in (d,p) and (d,n), and some recent data from (d,n) reactions in inverse kinematics using stable beams of 12C and 16O.Comment: 9 pages, 4 figures, presented at the XXXV Mazurian Lakes Conference on Physics, Piaski, Polan

    Experimental removals reveal dietary niche partitioning facilitates coexistence between native and introduced species

    Get PDF
    Niche overlap between native species and ecologically similar invaders can lead to competitive exclusion of threatened native species, but if two such species also co-occur naturally elsewhere, interactions between native and introduced populations may mirror coevolved niche partitioning that reduces competition and promotes coexistence.A single, insular population of Fremont's squirrel (Tamiasciurus fremonti) the Mount Graham red squirrel (MGRS; T. f. grahamensis) in the Pinaleño Mountains, Arizona, USA, is critically endangered and resource competition with introduced Abert's squirrels (Sciurus aberti) may threaten its long-term persistence. The species are naturally synoptic in other mountain sites, and both consume diets comprised primarily of conifer seeds and fungi.We conducted experimental removals of introduced Abert's squirrels and used stable isotope analysis of diets before and after removals, and of diets in naturally syntopic populations to test the hypothesis that dietary niche partitioning can facilitate coexistence between native and introduced species. We also developed a novel approach to determine the influence of fluctuating food availability on carbon enrichment in consumers.Mount Graham red squirrels and introduced Abert's squirrels partitioned the dietary niche similarly to naturally syntopic populations. Removals had no apparent effect. Diet of MGRS was more closely linked to availability of resources than to presence of Abert's squirrels.Flexible dietary niche of introduced Abert's squirrels may have allowed them to exploit a resource opportunity in syntopy with MGRS. Variable food production of MGRS habitat may intensify competition in poor years, and territorial defense against non-native Abert's squirrels likely imposes fitness costs on individual MGRS. Similarity in our model species' diets may make MGRS more vulnerable to competition if climate change eliminates the advantages of larder-hoarding. Where introduced populations of ecologically similar species are better adapted to changing conditions, they may ultimately replace southern peripheral populations of native species.USDA Forest Service; American Society of Mammalogists Grant in Aid of Research; T&E Inc. Grants for Conservation Biology; University of Arizona; Arizona Game and Fish DepartmentOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

    Key 19^{19}Ne states identified affecting γ\gamma-ray emission from 18^{18}F in novae

    Get PDF
    Detection of nuclear-decay γ\gamma rays provides a sensitive thermometer of nova nucleosynthesis. The most intense γ\gamma-ray flux is thought to be annihilation radiation from the β+\beta^+ decay of 18^{18}F, which is destroyed prior to decay by the 18^{18}F(pp,α\alpha)15^{15}O reaction. Estimates of 18^{18}F production had been uncertain, however, because key near-threshold levels in the compound nucleus, 19^{19}Ne, had yet to be identified. This Letter reports the first measurement of the 19^{19}F(3^{3}He,tγt\gamma)19^{19}Ne reaction, in which the placement of two long-sought 3/2+^+ levels is suggested via triton-γ\gamma-γ\gamma coincidences. The precise determination of their resonance energies reduces the upper limit of the rate by a factor of 1.5171.5-17 at nova temperatures and reduces the average uncertainty on the nova detection probability by a factor of 2.1.Comment: 6 pages, 4 figure
    corecore