920 research outputs found
The MEV project: design and testing of a new high-resolution telescope for Muography of Etna Volcano
The MEV project aims at developing a muon telescope expressly designed for
the muography of Etna Volcano. In particular, one of the active craters in the
summit area of the volcano would be a suitable target for this experiment. A
muon tracking telescope with high imaging resolution was built and tested
during 2017. The telescope is a tracker based on extruded scintillating bars
with WLS fibres and featuring an innovative read-out architecture. It is
composed of three XY planes with a sensitive area of \SI{1}{m^2}; the angular
resolution does not exceeds \SI{0.4}{\milli\steradian} and the total angular
aperture is about \SI{45}{\degree}. A special effort concerned the design
of mechanics and electronics in order to meet the requirements of a detector
capable to work in a hostile environment such as the top of a tall volcano, at
a far distance from any facility. The test phase started in January 2017 and
ended successfully at the end of July 2017. An extinct volcanic crater (the
Monti Rossi, in the village of Nicolosi, about 15km from Catania) is the target
of the measurement. The detector acquired data for about 120 days and the
preliminary results are reported in this work
Identification and characterization of PlAlix, the Alix homologue from the Mediterranean sea urchin Paracentrotus lividus.
The sea urchin provides a relatively simple and tractable system for analyzing the early stages of embryo development. Here, we use the sea urchin species, Paracentrotus lividus, to investigate the role of Alix in key stages of embryogenesis, namely the egg fertilization and the first cleavage division. Alix is a multifunctional protein involved in different cellular processes including endocytic membrane trafficking, filamentous (F)-actin remodeling, and cytokinesis. Alix homologues have been identified in different metazoans; in these organisms, Alix is involved in oogenesis and in determination/differentiation events during embryo development. Herein, we describe the identification of the sea urchin homologue of Alix, PlAlix. The deduced amino acid sequence shows that Alix is highly conserved in sea urchins. Accordingly, we detect the PlAlix protein cross-reacting with monoclonal Alix antibodies in extracts from P. lividus, at different developmental stages. Focusing on the role of PlAlix during early embryogenesis we found that PlAlix is a maternal protein that is expressed at increasingly higher levels from fertilization to the 2-cell stage embryo. In sea urchin eggs, PlAlix localizes throughout the cytoplasm with a punctuated pattern and, soon after fertilization, accumulates in larger puncta in the cytosol, and in microvilli-like protrusions. Together our data show that PlAlix is structurally conserved from sea urchin to mammals and may open new lines of inquiry into the role of Alix during the early stages of embryo development
Pro-invasive stimuli and the interacting protein Hsp70 favour the route of alpha-enolase to the cell surface
Cell surface expression of alpha-enolase, a glycolytic enzyme displaying moonlighting activities, has been shown to contribute to the motility and invasiveness of cancer cells through the protein non-enzymatic function of binding plasminogen and enhancing plasmin formation. Although a few recent records indicate the involvement of protein partners in the localization of alpha-enolase to the plasma membrane, the cellular mechanisms underlying surface exposure remain largely elusive. Searching for novel interactors and signalling pathways, we used low-metastatic breast cancer cells, a doxorubicin-resistant counterpart and a non-tumourigenic mammary epithelial cell line. Here, we demonstrate by a combination of experimental approaches that epidermal growth factor (EGF) exposure, like lipopolysaccharide (LPS) exposure, promotes the surface expression of alpha-enolase. We also establish Heat shock protein 70 (Hsp70), a multifunctional chaperone distributed in intracellular, plasma membrane and extracellular compartments, as a novel alpha-enolase interactor and demonstrate a functional involvement of Hsp70 in the surface localization of alpha-enolase. Our results contribute to shedding light on the control of surface expression of alpha-enolase in non-tumourigenic and cancer cells and suggest novel targets to counteract the metastatic potential of tumours
Correlated electron-hole plasma in organometal perovskites
Organic-inorganic perovskites are a class of solution-processed semiconductors holding promise for the realization of low-cost efficient solar cells and on-chip lasers. Despite the recent attention they have attracted, fundamental aspects of the photophysics underlying device operation still remain elusive. Here we use photoluminescence and transmission spectroscopy to show that photoexcitations give rise to a conducting plasma of unbound but Coulomb-correlated electron-hole pairs at all excitations of interest for light-energy conversion and stimulated optical amplification. The conductive nature of the photoexcited plasma has crucial consequences for perovskite-based devices: in solar cells, it ensures efficient charge separation and ambipolar transport while, concerning lasing, it provides a low threshold for light amplification and justifies a favourable outlook for the demonstration of an electrically driven laser. We find a significant trap density, whose cross-section for carrier capture is however low, yielding a minor impact on device performance
Notch-effector CSL promotes squamous cell carcinoma by repressing histone demethylase KDM6B.
Notch 1/2 genes play tumor-suppressing functions in squamous cell carcinoma (SCC), a very common malignancy in skin and internal organs. In contrast with Notch, we show that the transcription factor CSL (also known as RBP-Jκ), a key effector of canonical Notch signaling endowed with intrinsic transcription-repressive functions, plays a tumor-promoting function in SCC development. Expression of this gene decreased in upper epidermal layers and human keratinocytes (HKCs) undergoing differentiation, while it increased in premalignant and malignant SCC lesions from skin, head/neck, and lung. Increased CSL levels enhanced the proliferative potential of HKCs and SCC cells, while silencing of CSL induced growth arrest and apoptosis. In vivo, SCC cells with increased CSL levels gave rise to rapidly expanding tumors, while cells with silenced CSL formed smaller and more differentiated tumors with enhanced inflammatory infiltrate. Global transcriptomic analysis of HKCs and SCC cells with silenced CSL revealed major modulation of apoptotic, cell-cycle, and proinflammatory genes. We also show that the histone demethylase KDM6B is a direct CSL-negative target, with inverse roles of CSL in HKC and SCC proliferative capacity, tumorigenesis, and tumor-associated inflammatory reaction. CSL/KDM6B protein expression could be used as a biomarker of SCC development and indicator of cancer treatment
Periodontal and Orthodontic Synergy in the Management of Stage IV Periodontitis: Challenges, Indications and Limits
This retrospective study described the clinical and radiographic long-term outcomes of combined periodontal and orthodontic treatment (OT) with fixed appliances in patients with Stage IV periodontitis and pathologic tooth migration (PTM) in the anterior sextants. OT was performed in either one or both arches, using tooth-supported or skeletal anchorage, following completion of active periodontal treatment and accurate planning of tooth movement biomechanics. Twenty-nine patients were identified and retrospectively examined when presenting for a supportive periodontal care (SPC) appointment. The mean SPC duration was 8.9 years (range 5 to 12 years). All anterior-migrated teeth showed statistically significant periodontal improvement compared to baseline values and stable radiographic bone levels at the final follow-up. Residual probing depths were 2.9 ± 0.5 mm at the end of active periodontal treatment, and they remained stable at the completion of OT (2.9 ± 0.6 mm) and at the last follow-up visit (2.8 ± 0.5 mm). These findings suggest that OT is a safe and effective treatment in improving the long-term prognosis of teeth with PTM in Stage IV periodontitis provided that periodontal health has been re-established and maintained with individualized SPC sessions
Herschel Far-IR counterparts of SDSS galaxies: Analysis of commonly used Star Formation Rate estimates
We study a hundred of galaxies from the spectroscopic Sloan Digital Sky
Survey with individual detections in the Far-Infrared Herschel PACS bands (100
or 160 m) and in the GALEX Far-UltraViolet band up to z0.4 in the
COSMOS and Lockman Hole fields. The galaxies are divided into 4 spectral and 4
morphological types. For the star forming and unclassifiable galaxies we
calculate dust extinctions from the UV slope, the H/H ratio and
the ratio. There is a tight correlation between the
dust extinction and both and metallicity. We calculate
SFR and compare it with other SFR estimates (H, UV, SDSS)
finding a very good agreement between them with smaller dispersions than
typical SFR uncertainties. We study the effect of mass and metallicity, finding
that it is only significant at high masses for SFR. For the AGN and
composite galaxies we find a tight correlation between SFR and L
(0.29), while the dispersion in the SFR - L relation is
larger (0.57). The galaxies follow the prescriptions of the
Fundamental Plane in the M-Z-SFR space.Comment: 24 pages, 23 figures, accepted for publication in MNRA
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