4,526 research outputs found

    Supersymmetry Searches in GUT Models with Non-Universal Scalar Masses

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    We study SO(10), SU(5) and flipped SU(5) GUT models with non-universal soft supersymmetry-breaking scalar masses, exploring how they are constrained by LHC supersymmetry searches and cold dark matter experiments, and how they can be probed and distinguished in future experiments. We find characteristic differences between the various GUT scenarios, particularly in the coannihilation region, which is very sensitive to changes of parameters. For example, the flipped SU(5) GUT predict the possibility of t~1χ\tilde{t}_1-\chi coannihilation, which is absent in the regions of the SO(10) and SU(5) GUT parameter spaces that we study. We use the relic density predictions in different models to determine upper bounds for the neutralino masses, and we find large differences between different GUT models in the sparticle spectra for the same LSP mass, leading to direct connections of distinctive possible experimental measurements with the structure of the GUT group. We find that future LHC searches for generic missing ETE_T, charginos and stops will be able to constrain the different GUT models in complementary ways, as will the Xenon 1 ton and Darwin dark matter scattering experiments and future FERMI or CTA γ\gamma-ray searches.Comment: 21 pages, 10 Figures. V3: some comments and 1 reference added, published version. JCAP03(2016)04

    Preanalytical errors: the professionals’ perspective

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    This study was aimed at understanding the perspective on preanalytical errors from the point of view of the professionals involved in the preanalytical process. A significant contribution of their specialized knowledge and experience in day-to-day practice for identifying these kinds of mistakes, and their most frequent causes, was expected.It seems evident that weaknesses and threats are closely related to institutional organization aspects and the same is true for positive elements (strengths and opportunities). There is also an important appreciation of the staff’s implication. Staff´s opinions should be taken into account by institution managers, as they offer an approach that is different and complementary to the one traditionally applied, which is purely managerial and therefore not sufficient. The results should be complemented with more updated information. Multidisciplinary cooperation must involve not only professionals from different fields but also with different roles, i.e., managers, in order to obtain results that can be used to improve healthcare, save costs and to guarantee patient’s safety. We will continue with this research line investigating the same questions among primary care staff, in order to assess “the other side of the coin” of this problem.This study was partially supported by project Fondo de Investigaciones Sanitarias (FIS) grant PIFIS 1099/12 from “Instituto de Salud Carlos III” Ministerio de Sanidad y Política Social. Gobierno de España. (Health Ministry, Spanish Government).Yes2015-04-0

    Anticancer applications of nanostructured silica-based materials functionalized with titanocene derivatives: Induction of cell death mechanism through TNFR1 modulation

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    This article belongs to the Special Issue Nanomaterials for Biomedical ApplicationsA series of cytotoxic titanocene derivatives have been immobilized onto nanostructured silica-based materials using two different synthetic routes, namely, (i) a simple grafting protocol via protonolysis of the Ti-Cl bond; and (ii) a tethering method by elimination of ethanol using triethoxysilyl moieties of thiolato ligands attached to titanium. The resulting nanostructured systems have been characterized by different techniques such as XRD, XRF, DR-UV, BET, SEM, and TEM, observing the incorporation of the titanocene derivatives onto the nanostructured silica and slight changes in the textural features of the materials after functionalization with the metallodrugs. A complete biological study has been carried out using the synthesized materials exhibiting moderate cytotoxicity in vitro against three human hepatic carcinoma (HepG2, SK-Hep-1, Hep3B) and three human colon carcinomas (DLD-1, HT-29, COLO320) and very low cytotoxicity against normal cell lines. In addition, the cells' metabolic activity was modified by a 24-h exposure in a dose-dependent manner. Despite not having a significant effect on TNFalfa or the proinflammatory interleukin 1alfa secretion, the materials strongly modulated tumor necrosis factor (TNF) signaling, even at sub-cytotoxic concentrations. This is achieved mainly by upregulation of the TNFR1 receptor production, something which has not previously been observed for these systems.We gratefully acknowledge financial support from FEDER and the Ministerio de Economía y Competitividad, Spain (grant no. CTQ2015-66164-R) and the Romanian UEFISCDI Exploratory Research Project PN-III-P4-ID-PCE-2016-0870, IMPRESS. We would also like to thank Universidad Rey Juan Carlos and Banco de Santander for supporting our Research Group of Excellence QUINANOAP. Finally, we thank D. Pérez for valuable discussion and S. Carralero and C. Forcé for their assistance with solid-state NMR experiments

    The double-Kerr equilibrium configurations involving one extreme object

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    We demonstrate the existence of equilibrium states in the limiting cases of the double-Kerr solution when one of the constituents is an extreme object. In the `extreme-subextreme' case the negative mass of one of the constituents is required for the balance, whereas in the `extreme-superextreme' equilibrium configurations both Kerr particles may have positive masses. We also show that the well-known relation |J|=M^2 between the mass and angular momentum in the extreme single Kerr solution ceases to be a characteristic property of the extreme Kerr particle in a binary system.Comment: 12 pages, 3 figures, submitted to Class. Quantum Gra

    Broad N2H+ emission towards the protostellar shock L1157-B1

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    We present the first detection of N2H+ towards a low-mass protostellar outflow, namely the L1157-B1 shock, at about 0.1 pc from the protostellar cocoon. The detection was obtained with the IRAM 30-m antenna. We observed emission at 93 GHz due to the J = 1-0 hyperfine lines. The analysis of the emission coupled with the HIFI CHESS multiline CO observations leads to the conclusion that the observed N2H+(1-0) line originates from the dense (> 10^5 cm-3) gas associated with the large (20-25 arcsec) cavities opened by the protostellar wind. We find a N2H+ column density of few 10^12 cm-2 corresponding to an abundance of (2-8) 10^-9. The N2H+ abundance can be matched by a model of quiescent gas evolved for more than 10^4 yr, i.e. for more than the shock kinematical age (about 2000 yr). Modelling of C-shocks confirms that the abundance of N2H+ is not increased by the passage of the shock. In summary, N2H+ is a fossil record of the pre-shock gas, formed when the density of the gas was around 10^4 cm-3, and then further compressed and accelerated by the shock.Comment: ApJ, in pres

    The CHESS survey of the L1157-B1 bow-shock: high and low excitation water vapor

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    Molecular outflows powered by young protostars strongly affect the kinematics and chemistry of the natal molecular cloud through strong shocks resulting in substantial modifications of the abundance of several species. As part of the "Chemical Herschel Surveys of Star forming regions" guaranteed time key program, we aim at investigating the physical and chemical conditions of H20 in the brightest shock region B1 of the L1157 molecular outflow. We observed several ortho- and para-H2O transitions using HIFI and PACS instruments on board Herschel, providing a detailed picture of the kinematics and spatial distribution of the gas. We performed a LVG analysis to derive the physical conditions of H2O shocked material, and ultimately obtain its abundance. We detected 13 H2O lines probing a wide range of excitation conditions. PACS maps reveal that H2O traces weak and extended emission associated with the outflow identified also with HIFI in the o-H2O line at 556.9 GHz, and a compact (~10") bright, higher-excitation region. The LVG analysis of H2O lines in the bow-shock show the presence of two gas components with different excitation conditions: a warm (Tkin~200-300 K) and dense (n(H2)~(1-3)x10^6 cm-3) component with an assumed extent of 10" and a compact (~2"-5") and hot, tenuous (Tkin~900-1400 K, n(H2)~10^3-10^4 cm-3) gas component, which is needed to account for the line fluxes of high Eu transitions. The fractional abundance of the warm and hot H2O gas components is estimated to be (0.7-2)x10^{-6} and (1-3)x10^{-4}, respectively. Finally, we identified an additional component in absorption in the HIFI spectra of H2O lines connecting with the ground state level, probably arising from the photodesorption of icy mantles of a water-enriched layer at the edges of the cloud.Comment: Accepted for publication in A&A. 12 pages, 9 figures, 4 table

    Diagnosing shock temperature with NH3_3 and H2_2O profiles

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    In a previous study of the L1157 B1 shocked cavity, a comparison between NH3_3(10_0-000_0) and H2_2O(110_{\rm 10}--101_{\rm 01}) transitions showed a striking difference in the profiles, with H2_2O emitting at definitely higher velocities. This behaviour was explained as a result of the high-temperature gas-phase chemistry occurring in the postshock gas in the B1 cavity of this outflow. If the differences in behaviour between ammonia and water are indeed a consequence of the high gas temperatures reached during the passage of a shock, then one should find such differences to be ubiquitous among chemically rich outflows. In order to determine whether the difference in profiles observed between NH3_3 and H2_2O is unique to L1157 or a common characteristic of chemically rich outflows, we have performed Herschel-HIFI observations of the NH3_3(10_0-00_0) line at 572.5 GHz in a sample of 8 bright low-mass outflow spots already observed in the H2_2O(110_{\rm 10}--101_{\rm 01}) line within the WISH KP. We detected the ammonia emission at high-velocities at most of the outflows positions. In all cases, the water emission reaches higher velocities than NH3_3, proving that this behaviour is not exclusive of the L1157-B1 position. Comparisons with a gas-grain chemical and shock model confirms, for this larger sample, that the behaviour of ammonia is determined principally by the temperature of the gas.Comment: Accepted for publication in the Monthly Notices of the Royal Astronomical Societ
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