pinecone/core-2020-05-10-deduplication huggingface dataset:
Quasi-periodic oscillations in accreting magnetic white      dwarfs
 : 
II. The asset of numerical modelling for interpreting          observations

International audienceContext. Magnetic cataclysmic variables are close binary systems          containing a strongly magnetized white dwarf that accretes matter coming from an M-dwarf          companion. The high magnetic field strength leads to the formation of an accretion column          instead of an accretion disk. High-energy radiation coming from those objects is emitted          from the column close to the white dwarf photosphere at the impact region. Its properties          depend on the characteristics of the white dwarf and an accurate accretion column model          allows the properties of the binary system to be inferred, such as the white dwarf mass,          its magnetic field, and the accretion rate.Aims. We study the temporal and spectral behaviour of the accretion          region and use the tools we developed to accurately connect the simulation results to the          X-ray and optical astronomical observations.Methods. The radiation hydrodynamics code Hades was adapted to          simulate this specific accretion phenomena. Classical approaches were used to model the          radiative losses of the two main radiative processes: bremsstrahlung and cyclotron.          Synthetic light curves and X-ray spectra were extracted from numerical simulations. A fast          Fourier analysis was performed on the simulated light curves. The oscillation frequencies          and amplitudes in the X-ray and optical domains are studied to compare those numerical          results to observational ones. Different dimensional formulae were developed to complete          the numerical evaluations. Results. The complete characterization of the emitting region is          described for the two main radiative regimes: when only the bremsstrahlung losses and when          both cyclotron and bremsstrahlung losses are considered. The effect of the non-linear          cooling instability regime on the accretion column behaviour is analysed. Variation in          luminosity on short timescales (~1 s quasi-periodic oscillations) is an expected consequence of          this specific dynamic. The importance of secondary shock instability on the quasi-periodic          oscillation phenomenon is discussed. The stabilization effect of the cyclotron process is          confirmed by our numerical simulations, as well as the power distribution in the various          modes of oscillation
AMADEUS - The Acoustic Neutrino Detection Test System of the Deep-Sea ANTARES Neutrino Telescope

The AMADEUS system described in this article is integrated into the ANTARES neutrino telescope in the Mediterranean Sea and aims at the investigation of techniques for acoustic detection of neutrinos in the deep sea. Installed at water depths between 2000 and 2400m, its acoustic sensors employ piezo-electric elements for the broad-band recording of signals with frequencies ranging up to 125 kHz with typical sensitivities around −145 dB re. 1V/μPa (including preamplifier). Completed in May 2008, AMADEUS consists of six "acoustic clusters", each comprising six acoustic sensors that are arranged at distances of roughly 1m from each other. Three acoustic clusters each are installed along two vertical mechanical structures (so-called lines) of the ANTARES detector at a horizontal distance of 240m. Vertical spacings within a line range from 15m to 125m. Each cluster contains custom-designed electronics boards to amplify and digitise the acoustic data from the sensors. The data transmission to shore is done via optical fibres, using the TCP/IP protocol. An on-shore computer cluster, currently consisting of four dedicated servers, is used to process, filter and store the selected data. The daily volume of recorded data is about 10 - 20 GByte. The system is operating continuously and automatically, requiring only little human intervention. AMADEUS allows for extensive studies of both transient signals and ambient noise in the deep sea as well as signal correlations on several length scales and localisation of acoustic point sources. Thus the system is excellently suited to assess the background conditions that affect the measurement of bipolar pulses expected to originate from neutrino interactions. This in turn allows for feasibility studies of a future large-scale acoustic neutrino telescope in the Mediterranean Sea
Imagined Intergroup Contact and Common Ingroup Identity: An Integrative Approach

We conducted two studies involving two different age groups (elementary school children and adults) aimed at integrating imagined contact and common ingroup identity models. In the first study, Italian elementary school children were asked to imagine interacting with an unknown immigrant peer as members of a common group. Results revealed that common ingroup imagined contact, relative to a control condition, improved outgroup helping intentions assessed 1 week and 2 weeks after the intervention. In the second study, common ingroup imagined contact led Italian university students to display higher intentions to have contact with immigrants compared to control conditions. In conclusion, results from both studies demonstrate that imagining an intergroup interaction as members of the same group strengthens the effects of imagined contact. These findings point to the importance of combining the common ingroup identity model and the imagined contact theory in order to increase the potentiality of prejudice reduction interventions
ReaderBench: Automated evaluation of collaboration based on cohesion and dialogism

Dascalu, M., Trausan-Matu, S., McNamara, D.S., & Dessus, P. (2015). ReaderBench – Automated Evaluation of Collaboration based on Cohesion and Dialogism. International Journal of Computer-Supported Collaborative Learning, 10(4), 395–423. doi: 10.1007/s11412-015-9226-yAs Computer-Supported Collaborative Learning (CSCL) gains a broader usage, the need for automated tools capable of supporting tutors in the time-consuming process of
analyzing conversations becomes more pressing. Moreover, collaboration, which  presumes the intertwining of ideas or points of view among participants, is a central element of dialogue performed in CSCL environments. Therefore, starting from dialogism and a cohesion-based model of discourse, we propose and validate two computational models for assessing collaboration. The first model is based on a cohesion graph and can be perceived as a longitudinal analysis of the ongoing conversation, thus accounting for collaboration from a social knowledge-building perspective. In the second approach, collaboration is regarded from a dialogical perspective as the intertwining or synergy of voices pertaining to different speakers, therefore enabling a transversal analysis of subsequent discussion slices.This study is part of the RAGE project. The RAGE project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 644187.  This publication reflects only the author's view. The European Commission is not responsible for any use that may be made of the information it contains
Search for supersymmetry in events with photons, bottom quarks, and missing transverse momentum in proton-proton collisions at a centre-of-mass energy of 7 TeV with the ATLAS detector

A search has been performed for the experimental signature of an isolated photon with high transverse momentum, at least one jet identified as originating from a bottom quark, and high missing transverse momentum. Such a final state may originate from supersymmetric models with gauge-mediated supersymmetry breaking in events in which one of a pair of higgsino-like neutralinos decays into a photon and a gravitino while the other decays into a Higgs boson and a gravitino. The search is performed using the full dataset of 7 TeV proton–proton collisions recorded with the ATLAS detector at the LHC in 2011, corresponding to an integrated luminosity of 4.7 fb−1. A total of 7 candidate events are observed while 7.5±2.2 events are expected from the Standard Model background. The results of the search are interpreted in the context of general gauge mediation to exclude certain regions of a benchmark plane for higgsino-like neutralino production.We acknowledge the support of ANPCyT, Argentina; YerPhI, Armenia; ARC, Australia; BMWF and FWF, Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN; CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and VSC CR, Czech Republic; DNRF, DNSRC and Lundbeck Foundation, Denmark; EPLANET, ERC and NSRF, European Union; IN2P3-CNRS, CEA-DSM/IRFU, France; GNSF, Georgia; BMBF, DFG, HGF, MPG and AvH Foundation, Germany; GSRT and NSRF, Greece; ISF, MINERVA, GIF, DIP and Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS, Japan; CNRST, Morocco; FOM and NWO, Netherlands; BRF and RCN, Norway; MNiSW, Poland; GRICES and FCT, Portugal; MERYS (MECTS), Romania; MES of Russia and ROSATOM, Russian Federation; JINR; MSTD, Serbia; MSSR, Slovakia; ARRS and MVZT, Slovenia; DST/NRF, South Africa; MICINN, Spain; SRC and Wallenberg Foundation, Sweden; SER, SNSF and Cantons of Bern and Geneva, Switzerland; NSC, Taiwan; TAEK, Turkey; STFC, the Royal Society and Leverhulme Trust, United Kingdom; DOE and NSF, United States of America
Development of alginate-based hydrogels/cryogels by gelation under pressure

Published in "Journal of tissue engineering and regenerative medicine, vol. 8, s1 (June 2014)". Special Issue: Tissue Engineering & Regenerative Medicine International Society, European Chapter Meeting, 10–13 June, 2014, Genova, ItalyIntroduction: A tissue-engineered scaffold should provide suitable macroporous structure similar to that of extracellular matrix which can induce cellular activities and guide tissue regeneration. Hydrogels are biocompatible hydrophilic polymer structures that can imbibe large amounts of water or biological fluids. This work is aimed to present a novel method to fabricate alginate-based calcium cross-linked hydrogels by manipulating gelation at high pressure1 . The cryogels can be obtained after freeze-drying. Cryogels for biomedical applications are of special interest due to large and highly interconnected pores that provide non-constrained mass transfer for cell growth and proliferation. However, to achieve desirable mechanical properties as well as high adsorption capacity, bimodal meso and macroporous materials are greatly desirable2,3. Materials and methods: In this work two freezing regimes were studied in order to convert alginate-based hydrogels into cryogels, namely slow freezing at –80° C and rapid freezing in liquid nitrogen. Finally frozen materials were freeze dried. Hybrid cryogels (1.5 wt% alginate/1.5 wt% biopolymer) with gelatin, gellan gum, carboxymethylcellulose and lignin were prepared. Textural properties of the scaffolds were analyzed by SEM and micro-computed tomography. The mechanical properties of the cryogels were characterized in compression mode (wet and dry state). Finally, cytotoxicity studies by MTS were performed with a L929 cell line. Results: The results of SEM images indicate that slow freezing (– 80 °C) lead to purely macroporous materials, whereas rapid freezing in liquid nitrogen resulted in both meso and macroporous structures (Fig. 1). For instance, in case of alginate/Gelan gum the mean pore size of hybrid cryogels was approximately 190 lm with porosity of 52 %. The mechanical properties of the cryogels were also characterized in compression mode. Results show that the cryogels have Young’s modulus values approx. 1 MPa. Cytotoxicity studies were also carried and none of cryogels prepared present any cytotoxicity.
Discussion and conclusions: Hybrid alginate cryogels blended with gelatin, gellan gum, carboxymethylcellulose and lignin were successfully prepared by gelation under pressure. Rapid freezing with subsequent freeze-drying leads to high porosity both in meso and macro range. The results obtained suggest that developed cryogels have, hereafter, the potential to be used for tissue engineering and regenerative medicine.The authors are grateful for financial support of
FCT through grant EXP/QEQ-EPS/0745/2012, SWIMS. The authors
acknowledge the funding received from the FCT-DAAD bilateral agreement
Measurement of the inclusive isolated prompt photon cross section in pp collisions at √ s = 8 TeV with the ATLAS detector

A measurement of the cross section for the inclusive production of isolated prompt photons in proton-proton collisions at a centre-of-mass energy of s√=8 TeV is presented. The measurement covers the pseudorapidity ranges |ηγ | < 1.37 and 1.56 ≤ |ηγ | < 2.37 in the transverse energy range 25 < ETγ < 1500 GeV. The results are based on an integrated luminosity of 20.2 fb−1, recorded by the ATLAS detector at the LHC. Photon candidates are identified by combining information from the calorimeters and the inner tracker. The background is subtracted using a data-driven technique, based on the observed calorimeter shower-shape variables and the deposition of hadronic energy in a narrow cone around the photon candidate. The measured cross sections are compared with leading-order and next-to-leading order perturbative QCD calculations and are found to be in a good agreement over ten orders of magnitude
Search for heavy quarks decaying into a top quark and a W or Z boson using lepton + jets events in pp collisions at √s = 7 TeV

Journal of High Energy Physics 2013.1 (2013): 154 reproduced by permission of Scuola Internazionale Superiore di Studi Avanzati (SISSA)Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMResults are presented from a search for the pair-production of heavy quarks, QQ̄, that decay exclusively into a top quark and a W or Z boson. The search is performed using a sample of proton-proton collisions at √s = 7 TeV corresponding to an integrated luminosity of 5.0 fb-1, collected by the Compact Muon Solenoid experiment. The signal region is defined using a sample of events containing one electron or muon, missing transverse momentum, and at least four jets with large transverse momenta, where one jet is likely to originate from the decay of a bottom quark. No significant excess of events is observed with respect to the standard model expectations. Assuming a strong pair-production mechanism, quark masses below 675 (625) GeV decaying into tW (tZ) are excluded at the 95 % confidence leve
Radial velocity variations in the young eruptive star EX Lupi*'**

Astronomy and Astrophysics 561 (2014): A61 reproduced with permission from Astronomy & AstrophysicsContext. EX Lup-type objects (EXors) are low-mass pre-main sequence objects characterized by optical and near-infrared outbursts attributed to highly enhanced accretion from the circumstellar disk onto the star. Aims. The trigger mechanism of EXor outbursts is still debated. One type of theory requires a close (sub)stellar companion that perturbs the inner part of the disk and triggers the onset of the enhanced accretion. Here, we study the radial velocity (RV) variations of EX Lup, the prototype of the EXor class, and test whether they can be related to a close companion. Methods. We conducted a five-year RV survey, collecting 54 observations with HARPS and FEROS. We analyzed the activity of EX Lup by checking the bisector, the equivalent width of the Ca 8662 Å line, the asymmetry of the Ca II K line, the activity indicator S FEROS, the asymmetry of the cross-correlation function, the line depth ratio of the VI/FeI lines, and the TiO, CaH 2, CaH 3, CaOH, and Hα indices. We complemented the RV measurements with a 14-day optical/infrared photometric monitoring to look for signatures of activity or varying accretion. Results. We found that the RV of EX Lup is periodic (P = 7.417 d), with stable period, semi-amplitude (2.2 km s-1), and phase over at least four years of observations. This period is not present in any of the above-mentioned activity indicators. However, the RVs of narrow metallic emission lines suggest the same period, but with an anti-correlating phase. The observed absorption line RVs can be fitted with a Keplerian solution around a 0.6 M central star with msini = (14.7 ± 0.7) MJup and eccentricity of e = 0.24. Alternatively, we attempted to model the observations with a cold or hot stellar spot as well. We found that in our simple model, the spot parameters needed to reproduce the RV semi-amplitude are in contradiction with the photometric variability, making the spot scenario unlikely. Conclusions. We qualitatively discuss two possibilities to explain the RV data: a geometry with two accretion columns rotating with the star, and a single accretion flow synchronized with the orbital motion of the hypothetical companion; the second scenario is more consistent with the observed properties of EX Lup. In this scenario, the companion's mass would fall into the brown dwarf desert, which, together with the unusually small separation of 0.06 au would make EX Lup a unique binary system. The companion also has interesting implications on the physical mechanisms responsible for triggering the outburstA.S.A. acknowledges support of the Spanish MICINN/MINECO “Ramón y Cajal” program, grant number RYC-2010-06164, and the action “Proyectos de Investigación fundamental no orientada”, grant number AYA2012-35008. This work was partly supported by the grant OTKA K101393 of the Hungarian Scientific Research Fun
Dynamic shaping of human NK cell receptor repertoires : implications for NK cell-based immunotherapy

Natural killer (NK) cells are innate lymphocytes with a potent intrinsic capacity to kill tumor cells, which makes them attractive candidates for cell-based cancer immunotherapy. Advances during the past decade have revealed that NK cells display a high degree of functional plasticity, suggesting that some subsets may be more effective in targeting cancer cells. In this thesis I have investigated the dynamic shaping of human NK cell repertoires with a focus on the biology and tumor killing potential of “adaptive” NK cells developing in response to human cytomegalovirus infection (HCMV).



In the first part of this thesis we performed an in depth analysis of the NK cell killer immunoglobulin-like receptor (KIR) repertoire in a cohort of 204 healthy individuals. We found a subset of NK cells that displayed evidence of clonal-like expansion in HCMV seropositive individuals (referred to as adaptive or memory NK cells). These cells displayed a highly differentiated phenotype and distinct functional properties, characterized by a strong potential to perform antibody-dependent cellular cytotoxicity (ADCC). Furthermore, these NK cells had a preferential expression of self-specific KIRs.



It is well established that the expression of KIR is genetically hardwired. In line with this, we found a linear correlation between KIR copy number variation (CNV) and the frequency of KIR expression. Although CNV had no effect on education at the single cell level, it influenced the overall size of the educated NK cell pool. However, KIR CNV had no effect on the frequency or magnitude of adaptive NK cell responses in HCMV seropositive individuals.



A series of studies have linked the activating receptor NKG2C to the expansions observed in association to HCMV infection. To investigate whether other pathways could be involved in driving adaptive NK cell responses we analyzed NK cell repertoires in donors carrying a homozygous deletion of the NKG2C gene. We found that these individuals were fully capable of mounting adaptive NK cell responses and that CD2 co-stimulation of CD16 signaling play a crucial role in NK cell-mediated ADCC by adaptive NK cells, suggesting that CD2 and CD16 could compensate for the loss of NKG2C in the presence of HCMV antibodies. Furthermore, this indicated that, like the T cell activation model, NK cells also require multiple steps to become fully activated, where CD2 co-stimulation represents “signal-2”.



Based on the insights into the regulation of adaptive NK cells, we established a platform for selective expansion of this highly cytotoxic NK cell subset. We found that in vitro expanded, and functionally reprogrammed, adaptive NK cells showed potent and specific killing of primary acute lymphoid leukemia (ALL) blasts, suggesting that this strategy may be effective in the context of cell-based cancer immunotherapy
Ru(III)​-​catalyzed oxidation of some amines by chloramine-​T in hydrochloric acid medium: Mechanistic aspects and kinetic modeling

A review.  The kinetics of oxidn. of five amines viz., ethylenediamine (EDA)​, diethylenetriamine (DETA)​, triethylenetetramine (TETA)​, aminoethylpiperazine (AEP) and isophoronediamine (IPDA) by sodium N-​chloro-​p-​toluenesulfonamide or chloramine-​T (CAT) in the presence of HCl and Ru(III) chloride was studied at 303 K. The five reactions followed identical kinetics and the exptl. rate law is rate = k[CAT]​0[amine]​x0[H+]​y[Ru(III)​]​z, where x, y and z are fractions.  A variation of the ionic strength or dielec. const. of the medium and the addn. of halide ions and p-​toluenesulfonamide had no significant effect on the rate of the reaction.  The solvent isotope effect has been studied in D2O medium.  The activation parameters have been evaluated from the Arrhenius plots.  Under comparable exptl. conditions, the rate of oxidn. of amines increases in the order: AEP > TETA > DETA > EDA > IPDA.  An isokinetic relationship is obsd. with β = 377 K, indicating enthalpy as a controlling factor.  Oxidn. products were identified.  CH3C6H4SO2+NH2Cl of the oxidant has been postulated as the reactive oxidizing species.  Further, the kinetics of Ru(III)​-​catalyzed oxidn. of these amines have been compared with unanalyzed reactions (in the absence of Ru(III) catalyst) and found that the catalyzed reactions are 2-​3-​fold faster.  The catalytic const. (KC) was also calcd. for each amine at different temps. from the plots of log KC against 1​/T, values of activation parameters with respect to the catalyst have been evaluated.  The obsd. results have also been explained by a plausible mechanism and the related rate law has been deduced
Lower limit on the gravitino mass in low-scale gauge mediation with
  $m_H\simeq 125$GeV

We revisit low-scale gauge mediation models in light of recent observations
of CMB Lensing and Cosmic Shear which put a severe upper limit on the gravitino
mass, $m_{3/2} \lesssim 4.7$eV. With such a stringent constraint, many models
of low-scale gauge mediation are excluded when the squark masses are required
to be rather large to explain the observed Higgs boson mass. In this note, we
discuss a type of low-scale gauge mediation models which satisfy both the
observed Higgs boson mass and the upper limit on the gravitino mass. We also
show that the gravitino mass cannot be smaller than about 1eV even in such
models, which may be tested in future observations of 21 cm line fluctuations.Comment: 13 pages, 1 figur