In this work a simulation of the electron drift which accounts for diffusion for different configurations of the electric field for the ReD detector has been carried out. An estimate of the ...reconstruction error of the event coordinates, caused both by nonuniformity of the field and by the focusing of electrons as they pass through the detector grid, is obtained.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this paper, a dependence of the erosion of graphite under a high energy ion flux at temperature of 2050°C on the ion dose is investigated. It is shown that, at ion flux densitiy of 1.42×1022 ...ion/m2s, irradiation stimulates diffusion processes that lead to the removal of carbon atoms from the bulk of the sample, leading to the formation of a porous layer, whereas, for ion flux density of 1.4×1020 ion/m2s, no such layer is formed.
Asthma is an increasingly common disease that remains poorly understood and difficult to manage. This disease is characterized by airway hyperreactivity (AHR, defined by exaggerated airflow ...obstruction in response to bronchoconstrictors), mucus overproduction and chronic eosinophilic inflammation. AHR and mucus overproduction are consistently linked to asthma symptoms and morbidity. Asthma is mediated by Th2 lymphocytes, which produce a limited repertoire of cytokines, including interleukin-4 (IL-4), IL-5, IL-9 and IL-13. Although each of these cytokines has been implicated in asthma, IL-13 is now thought to be especially critical. In animal models of allergic asthma, blockade of IL-13 markedly inhibits allergen-induced AHR, mucus production and eosinophilia. Furthermore, IL-13 delivery to the airway causes all of these effects. IL-13 is thus both necessary and sufficient for experimental models of asthma. However, the IL-13-responsive cells causing these effects have not been identified. Here we show that mice lacking signal transducer and activator of transcription 6 (STAT6) were protected from all pulmonary effects of IL-13. Reconstitution of STAT6 only in epithelial cells was sufficient for IL-13-induced AHR and mucus production in the absence of inflammation, fibrosis or other lung pathology. These results demonstrate the importance of direct effects of IL-13 on epithelial cells in causing two central features of asthma.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Abstract
Directional sensitivity to nuclear recoils would provide a smoking gun for a possible discovery of dark matter in the form of WIMPs (Weakly Interacting Massive Particles). A hint of ...directional dependence of the response of a dual-phase argon Time Projection Chamber (TPC) was found in the SCENE experiment. Given the potential importance of such a capability in the framework of dark matter searches, a new dedicated experiment, ReD (Recoil Directionality), was designed by the Global Argon Dark Matter Collaboration, in order to scrutinise this hint. A small dual-phase argon TPC was irradiated with neutrons produced by the p(
7
Li,
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Be)n reaction using the 15 MV TANDEM accelerator of the INFN - Laboratori Nazionali del Sud, Catania, Italy, so as to produce argon nuclear recoils in the range (20 - 100) keV of interest for dark matter searches. Energy and direction of nuclear recoils are inferred by the detection of the elastically-scattered neutron by a set of scintillation detectors. Events were selected by gating of the associated
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Be, which is detected by a telescope of Si detectors.
Abstract Liquid Argon (LAr) Time Projection Chambers (TPC) operating in double-phase can detect the nuclear recoils (NR) possibly caused by the elastic scattering of WIMP dark matter particles via ...light signals from both scintillation and ionization processes. In the scenario of a low-mass WIMP (< 2 GeV/c 2 ), the energy range for the NRs would be below 20 keV, thus making it crucial to characterize the ionization response in LAr TPCs as the lone available detection channel at such low energy. The Recoil Directionality (ReD) project, within the Global Argon Dark Matter Collaboration, aims to measure the ionization yield of a LAr TPC in the recoil energy range of 2–5 keV. The measurement was performed in winter 2023 at the INFN Sezione of Catania and the analysis is ongoing.
The Recoil Directionality (ReD) Experiment Sanfilippo, S; Agnes, P; Albergo, S ...
Journal of physics. Conference series,
11/2022, Volume:
2374, Issue:
1
Journal Article
Peer reviewed
Open access
Directional sensitivity to nuclear recoils would provide a smoking gun for a possible discovery of dark matter in the form of WIMPs (Weakly Interacting Massive Particles). A hint of directional ...dependence of the response of a dual-phase argon Time Projection Chamber (TPC) was found in the SCENE experiment. Given the potential importance of such a capability in the framework of dark matter searches, a new dedicated experiment, ReD (Recoil Directionality), was designed by the Global Argon Dark Matter Collaboration, in order to scrutinize this hint. Prior to the irradiation with a neutron beam, the ReD TPC underwent a long campaign of characterization and optimization: some selected results are presented in this contribution.
Macrophages are believed to play a central role in emphysema based largely on data from mouse models. However, the relevance of these models to smoking-related lung disease in humans is uncertain.
We ...sought to comprehensively characterize the effects of smoking on gene expression in human alveolar macrophages and to compare these with effects seen in transgenic mouse models of emphysema.
We used DNA microarrays with genomewide coverage to analyze alveolar macrophages from 15 smokers, 15 nonsmokers, and 15 subjects with asthma (disease control). Selected gene expression changes were validated by polymerase chain reaction and ELISA. Expression changes were compared with those identified by microarray analysis of interleukin-13-overexpressing and integrin-beta6-deficient mice, which both develop emphysema.
All 15 smokers shared a common pattern of macrophage gene expression that distinguished them from nonsmokers, a finding not observed in subjects with asthma. We identified 110 genes as differentially expressed in smokers despite using conservative statistical methods. Matrix metalloproteinase 12, a proteinase that plays a critical role in mouse models, was the third most highly induced gene in smokers (ninefold, p < 0.0001). However, most changes in smokers were not reflected in mouse models. One such finding was increased osteopontin expression in smokers (fourfold, p = 0.006), which was confirmed at the protein level and correlated with the degree of airway obstruction.
Smoking induces a remarkably consistent and distinctive pattern of alveolar macrophage activation. These studies identify aspects of mouse models that are directly relevant to human smokers and also reveal novel potential mediators of smoking-related diseases.
In this paper, a dependence of the erosion of graphite under a high energy ion flux from the ion dose is investigated at temperatures of 750, 1700 and 2050 °C. High doses of irradiation stimulate ...diffusion processes that lead to the transport of carbon atoms from the bulk of the sample towards the surface, leading to the formation of a porous layer which thickness increases both with the increase of sample's temperature, as well as the dose of irradiation.
Asthma functional genomics studies are challenging because it is difficult to relate gene expression changes to specific disease mechanisms or pathophysiologic features. Use of simplified model ...systems might help to address this problem. One such model is the IL-13/Epi (IL-13–overexpressing transgenic mice with STAT6 expression limited to epithelial cells) focused transgenic mouse, which isolates the effects of a single mediator, IL-13, on a single cell type, the airway epithelial cell. These mice develop airway hyperreactivity and mucus overproduction but not airway inflammation.
To identify how effects of IL-13 on airway epithelial cells contribute to gene expression changes in murine asthma models and determine whether similar changes are seen in people with asthma.
We analyzed gene expression in ovalbumin allergic mice, IL-13–overexpressing mice, and IL-13/Epi mice with microarrays. We analyzed the expression of human orthologues of genes identified in the mouse studies in airway epithelial cells from subjects with asthma and control subjects.
In comparison with the other 2 models, IL-13/Epi mice had a remarkably small subset of gene expression changes. Human orthologues of some genes identified as increased in the mouse models were more highly expressed in airway epithelial cells from subjects with asthma than in controls. These included calcium-activated chloride channel 1, 15-lipoxygenase, trefoil factor 2, and intelectin.
The combination of focused transgenic models, DNA microarray analyses, and translational studies provides a powerful approach for analyzing the contributions of specific mediators and cell types and for focusing attention on a limited number of genes associated with specific pathophysiologic aspects of asthma.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In this paper, a dependence of the erosion of graphite under a high energy ion flux at temperature of 2050 °C on the ion dose is investigated. It is shown that high doses of irradiation stimulate ...diffusion processes that lead to the removal of carbon atoms from the bulk of the sample, significantly altering morphology of graphite at depths exceeding penetration depth of irradiating ions for large doses.
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