4,042 research outputs found
A consistent interpretation of the Karmen anomaly
The Karmen anomaly can be interpreted as being due to a heavy neutrino of
mass around 137 MeV produced in decays. This interpretation is
consistent with the present limits on the couplings of such an object.Comment: 11pages, 4figures, Te
Lossless polarization attraction of co-propagating beams in telecom fibers
4We study the performance of a nonlinear lossless polarizer (NLP), the device that transforms an input arbitrary state of polarization (SOP) of a signal beam into one and the same SOP toward the output and, unlike conventional passive polarizers, performs this transformation without polarization-dependent losses. The operation principle of this device is based on the nonlinear rotation of the SOP of the strong signal beam under the interaction with a copropagating strong pump beam in a Kerr medium, which in our case is a telecom fiber. We quantify the performance of this NLP by introducing the notion of instantaneous degree of polarization, which is a natural extension of the conventional notion of the degree of polarization appropriate for CW beams to the case of pulses whose SOP is not constant across the pulse. We pay particular attention to the regime when signal and pump beams experience a walk-off in the dispersive medium. In particular, we demonstrate that a signal pulse experiences much stronger repolarization when the walk-off effect is present as compared with the case of no walk-off. We also study the degradation of the efficiency of the NLP in the presence of polarization mode dispersion.openopenV. Kozlov; M. Barozzi; A. Vannucci; S. WabnitzKozlov, Victor; M., Barozzi; A., Vannucci; Wabnitz, Stefa
Joint Bayesian variable and graph selection for regression models with network-structured predictors
In this work, we develop a Bayesian approach to perform selection of predictors that are linked within a network. We achieve this by combining a sparse regression model relating the predictors to a response variable with a graphical model describing conditional dependencies among the predictors. The proposed method is well-suited for genomic applications because it allows the identification of pathways of functionally related genes or proteins that impact an outcome of interest. In contrast to previous approaches for network-guided variable selection, we infer the network among predictors using a Gaussian graphical model and do not assume that network information is availableᅠa priori. We demonstrate that our method outperforms existing methods in identifying network-structured predictors in simulation settings and illustrate our proposed model with an application to inference of proteins relevant to glioblastoma survival.
Screening for developmental disorders in 3- and 4-year-old italian children: a preliminary study
BACKGROUND:
The "Osserviamo" project, coordinated by the Municipality of Rome and the Department of Pediatrics and Child Neuropsychiatry of Sapienza University, aimed to validate an Italian version of the Ages and Stages Questionnaire-3 and to collect, for the first time in Italy, data on developmental disorders in a sample of 4,000 children aged 3 and 4 years. The present paper presents the preliminary results of the "Osserviamo" project.
METHODS:
600 parents of children between 39 and 50 months of age (divided in two age stages: 42 and 48 months) were contacted from 15 kindergarden schools.
RESULTS:
23.35% of the whole sample scored in the risk range of at least one developmental area of the Ages and Stages Questionnaire-3rd Edition (ASQ-3) and 7.78% scored in the clinical range. Specifically, 23.97% of the children in the 42-month age stage scored in the risk range and 5.79% scored in the clinical range. Males scored lower than females in the fine motor skills and personal-social development domains. Moreover, 22.79% of the children in the 48-month age stage scored in the risk range, while 9.55% scored in the clinical range. Males scored lower than females in fine motor skills.
CONCLUSION:
Italian validation of the ASQ-3 and recruitment of all 4,000 participants will allow these data on the distribution of developmental disorders to be extended to the general Italian pediatric population. One main limitation of the study is the lack of clinical confirmation of the data yielded by the screening programme, which the authors aim to obtain in later stages of the study
The Category of Node-and-Choice Forms, with Subcategories for Choice-Sequence Forms and Choice-Set Forms
The literature specifies extensive-form games in many styles, and eventually
I hope to formally translate games across those styles. Toward that end, this
paper defines , the category of node-and-choice forms. The
category's objects are extensive forms in essentially any style, and the
category's isomorphisms are made to accord with the literature's small handful
of ad hoc style equivalences.
Further, this paper develops two full subcategories: for
forms whose nodes are choice-sequences, and for forms whose
nodes are choice-sets. I show that is "isomorphically enclosed"
in in the sense that each form is isomorphic to
a form. Similarly, I show that is
isomorphically enclosed in in the sense that each
form with no-absentmindedness is isomorphic to a
form. The converses are found to be almost immediate, and the
resulting equivalences unify and simplify two ad hoc style equivalences in
Kline and Luckraz 2016 and Streufert 2019.
Aside from the larger agenda, this paper already makes three practical
contributions. Style equivalences are made easier to derive by [1] a natural
concept of isomorphic invariance and [2] the composability of isomorphic
enclosures. In addition, [3] some new consequences of equivalence are
systematically deduced.Comment: 43 pages, 9 figure
Geometria e modellazione di un sistema di retro-scorrimenti attivosulla base di dati di geofisica marina ad alta risoluzione:la Dorsale di Amendolara (Golfo di Taranto).
Nuovi dati sismici ad alta (Sparker) ed altissima (Subbottm Chirp) risoluzione, acquisiti durante la
Campagna Oceanografica “Teatioca_2010”, integrati da dati sismici multicanale ad alta penetrazione,
pubblici disponibili sul sito www.videpi.com, calibrati con pozzi profondi, batimetrici multifascio e
carotaggi, rivelano che la dorsale di Amendolara, estensione sottomarina della zona frontale del sistema a
thrust dell’Appennino meridionale, è stata controllata nel Quaternario da un sistema di retro-scorrimenti e
faglie transpressive (ATFS) che dislocano verso SW la catena mio-pliocenica NE-vergente.
Il pacco di sequenze deposizionali attribuito, sulla base della facies sismica e della presenza di
discordanze controllate dalle oscillazioni glacio-eustatiche, al Pleistocene medio-superiore risulta piegato in
maniera consistente con le strutture desumibili dai profili multicanale. I dati morfometrici e sismici
documentano che la dorsale, orientata NW-SE, è formata da 3 banchi lunghi ~10-20 km, cresciuti sopra
rampe di sovrascorrimenti ciechi (~2 km) disposti en-echelon a formare un sistema segmentato. Sono stati
individuati e modellati i segmenti di Amendolara a NW e Cariati a SE, collegati da una più piccola rampa
laterale (segmento di Rossano). La modellazione numerica calibrata sui dati batimetrici e sismici indica che
le rampe hanno inclinazione di ~45° e sono radicate a ~10 km di profondità a possibili scollamenti o strutture
maggiori. I tassi di scorrimento negli ultimi 4-500 ka, calcolati per i segmenti sulla base degli strati di
crescita nei bacini sin tettonici variano da 0.5-0-9 mm/a per il segmento di Amendolara a 0.35-0.5 mm/a per
quello di Cariati.
L’ATFS coincide con una fascia di moderata sismicità (Mw<4.7) con meccanismi focali inversi o
transpressivi. L’orientazione degli assi di strain incrementale (sismico) e finito (geologico, come
documentano i dati a terra) suggerisce per i segmenti dell’ATFS un movimento da inverso a obliquo sinistro.
In base alla dimensione dei segmenti di faglia, nell’ipotesi di deformazione puramente elastica, si stima una
magnitudo potenziale massima per l’ATFS di M~6.1-6.4, ma è verosimile che buona parte della
deformazione sia asismica o microsismica. L’epicentro macrosismico del terremoto del 1988 (Mw=4.9)
ricade su un tratto del segmento di Cariati che mostra rotture a fondo mare e possibile risalita di fluidi
localizzata lungo strutture attive. La crescita dell’ATFS è stata verosimilmente controllata da un interfaccia
meccanica tra la spessa crosta apula e la crosta ionica assottigliata o in parte oceanica, quando in tempi
recenti la convergenza Adria-Europa ha prevalso sull’arretramento della cerniera della subduzione ionica
Production of Electron Neutrinos at Nuclear Power Reactors and the Prospects for Neutrino Physics
High flux of electron neutrinos(\nue) is produced at nuclear power reactors
through the decays of nuclei activated by neutron capture. Realistic simulation
studies on the neutron transport and capture at the reactor core were
performed. The production of \chr51 and \fe55 give rise to mono-energetic
\nue's at Q-values of 753 keV and 231 keV and fluxes of
and \nue/fission, respectively. Using data from a
germanium detector at the Kuo-Sheng Power Plant, we derived direct limits on
the \nue magnetic moment and the radiative lifetime of \mu_{\nu} < 1.3
\times 10^{-8} ~ \mub and at 90%
confidence level (CL), respectively. Indirect bounds on were also inferred. The \nue-flux can be enhanced by loading
selected isotopes to the reactor core, and the potential applications and
achievable statistical accuracies were examined. These include accurate
cross-section measurements, studies of mixing angle and
monitoring of plutonium production.Comment: 5 pages, 3 figures, 7 table
Why are we not flooded by involuntary thoughts about the past and future? Testing the cognitive inhibition dependency hypothesis
© The Author(s) 2018In everyday life, involuntary thoughts about future plans and events occur as often as involuntary thoughts about the past. However, compared to involuntary autobiographical memories (IAMs), such episodic involuntary future thoughts (IFTs) have become a focus of study only recently. The aim of the present investigation was to examine why we are not constantly flooded by IFTs and IAMs given that they are often triggered by incidental cues while performing undemanding activities. One possibility is that activated thoughts are suppressed by the inhibitory control mechanism, and therefore depleting inhibitory control should enhance the frequency of both IFTs and IAMs. We report an experiment with a between-subjects design, in which participants in the depleted inhibition condition performed a 60-min high-conflict Stroop task before completing a laboratory vigilance task measuring the frequency of IFTs and IAMs. Participants in the intact inhibition condition performed a version of the Stroop task that did not deplete inhibitory control. To control for physical and mental fatigue resulting from performing the 60-min Stroop tasks in experimental conditions, participants in the control condition completed only the vigilance task. Contrary to predictions, the number of IFTs and IAMs reported during the vigilance task, using the probe-caught method, did not differ across conditions. However, manipulation checks showed that participants’ inhibitory resources were reduced in the depleted inhibition condition, and participants were more tired in the experimental than in the control conditions. These initial findings suggest that neither inhibitory control nor physical and mental fatigue affect the frequency of IFTs and IAMs.Peer reviewedFinal Published versio
New Constraints on Dispersive Form Factor Parameterizations from the Timelike Region
We generalize a recent model-independent form factor parameterization derived
from rigorous dispersion relations to include constraints from data in the
timelike region. These constraints dictate the convergence properties of the
parameterization and appear as sum rules on the parameters. We further develop
a new parameterization that takes into account finiteness and asymptotic
conditions on the form factor, and use it to fit to the elastic \pi
electromagnetic form factor. We find that the existing world sample of timelike
data gives only loose bounds on the form factor in the spacelike region, but
explain how the acquisition of additional timelike data or fits to other form
factors are expected to give much better results. The same parameterization is
seen to fit spacelike data extremely well.Comment: 24 pages, latex (revtex), 3 eps figure
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