5311. Large-Scale Distribution of Arrival Directions of Cosmic Rays Detected at the Pierre Auger Observatory and the Telescope Array above 10[sup]19 eVOlivier Deligny, Andrej Filipčič, Gašper Kukec Mezek, Ahmed Saleh, Samo Stanič, Marta Trini, Darko Veberič, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, 2015, objavljeni znanstveni prispevek na konferenci Opis: The large-scale distribution of arrival directions of
high-energy cosmic rays is a key observable in attempts to
understanding their origin. The dipole and quadrupole moments
are of special interest in revealing potential anisotropies.
An unambiguous measurement of these moments as well as
of the full set of spherical harmonic coefficients requires
full-sky coverage. This can be achieved by combining data from
observatories located in both the northern and southern
hemispheres. To this end, a joint analysis using data recorded
at the Pierre Auger Observatory and the Telescope Array above
10[sup]19 eV has been performed. Thanks to the full-sky
coverage, the measurement of the dipole moment reported in
this study does not rely on any assumption on the underlying
flux of cosmic rays. As well, the resolution on the quadrupole
and higher order moments is the best ever obtained. The
resulting multipolar expansion of the flux of cosmic rays
allows a series of anisotropy searches to be performed,
and in particular to report on the first angular power
spectrum of cosmic rays. This allows a comprehensive
description of the angular distribution of cosmic rays
above 10[sup]19 eV. Ključne besede: Pierre Auger Observatory, Telescope Array, high-energy cosmic rays, large-scale anisotropies, angular power spectrum Objavljeno v RUNG: 08.03.2016; Ogledov: 4511; Prenosov: 189 Celotno besedilo (462,61 KB) |
5312. Report of the Working Group on the Composition of Ultra-High Energy Cosmic RaysMichael Unger, Andrej Filipčič, Gašper Kukec Mezek, Ahmed Saleh, Samo Stanič, Marta Trini, Darko Veberič, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, 2015, objavljeni znanstveni prispevek na konferenci Opis: The atmospheric depth, Xmax, at which the particle number of
an air shower reaches its maximum is a good indicator for the
mass of the primary particle. We present a comparison of the
energy evolution of the mean of Xmax as measured by the
Telescope Array and c Collaborations. After
accounting for the different resolutions, acceptances and
analysis strategies of the two experiments, the two results are
found to be in good agreement within systematic uncertainties. Ključne besede: Pierre Auger Observatory, Telescope Array, Ultra-High Energy Cosmic Rays, elemental composition, extensive air showers, the atmospheric depth of the air shower maximum Objavljeno v RUNG: 08.03.2016; Ogledov: 4694; Prenosov: 235 Celotno besedilo (329,86 KB) |
5313. Search for a correlation between the UHECRs measured by the Pierre Auger Observatory and the Telescope Array and the neutrino candidate events from IceCubeAsen Christov, Andrej Filipčič, Gašper Kukec Mezek, Ahmed Saleh, Samo Stanič, Marta Trini, Darko Veberič, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, 2015, objavljeni znanstveni prispevek na konferenci Opis: We have conducted three searches for correlations between
ultra-high energy cosmic rays detected by the Telescope Array
and the Pierre Auger Observatory, and high-energy neutrino
candidate events from IceCube. Two cross-correlation analyses
with UHECRs are done: one with 39 cascades from the IceCube
‘high-energy starting events’ sample and the other with 16
high-energy ‘track events’. The angular separation between the
arrival directions of neutrinos and UHECRs is scanned over.
The same events are also used in a separate search using a
maximum likelihood approach, after the neutrino arrival
directions are stacked. To estimate the significance we assume
UHECR magnetic deflections to be inversely proportional to
their energy, with values 3◦, 6◦ and 9◦ at 100 EeV to allow for
the uncertainties on the magnetic field strength and UHECR
charge. A similar analysis is performed on stacked UHECR
arrival directions and the IceCube sample of through-going
muon track events which were optimized for neutrino point-
source searches. Ključne besede: ultra-high energy cosmic rays, Pierre Auger Observatory, Telescope Array, high-energy neutrinos, IceCube, correlation search Objavljeno v RUNG: 08.03.2016; Ogledov: 4955; Prenosov: 192 Celotno besedilo (1,11 MB) |
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5315. A multi-level approach to the analysis of narrative language in aphasiaAndrea Marini, Sara Andreetta, Silvana Del Tin, Sergio Carlomagno, 2011, izvirni znanstveni članek Opis: Several studies have shown that traditional standardised aphasia tests may not be sensitive enough to adequately assess linguistic deficits and recovery patterns in persons with aphasia. As a result, both functional and structural methods for the ana- lysis of connected language samples from people with aphasia have been devised (see Armstrong, 2000; Prins & Bastiaanse, 2004).
The present article focuses on our attempt to provide a comprehensive, multi-level procedure for both structural and functional analysis of narrative discourse produced by speakers with brain damage. Accordingly, we will describe a method for analysis of connected language samples elicited on single picture and cartoon story description tasks. This method has proven sensitive in the assessment of language deficits in many neurogenic populations.
A comprehensive description of the language production sys- tem, a thorough discussion of the different approaches to discourse analysis in persons with aphasia, and the procedure for the analysis of narrative discourse are detailed. The characteristics of the eliciting stimuli, the procedures for their administration and the transcription of the language samples are carefully explained. The analysis focuses on four main aspects of linguistic processing: productivity, lexical and grammatical pro- cessing, narrative organisation, and informativeness. To further illustrate the analytic procedure, two case reports and an appendix with the analysis of a narrative sample are provided.
We will provide direct evidence of the usefulness of the multi-level procedure for discourse analysis for assessing changes in discourse performance of two persons with fluent aphasia, with different aetiologies, that were not captured by tradi- tional standardised aphasia tests.
The method of analysis presented in this paper has strong grounds in linguistic and psychological theories of linguistic structure and functioning. It also has the advantage of being both quantitative and functional as it captures selective aspects of linguistic processing, and can provide relevant information about the person's communicative and informative skills. Ključne besede: aphasia, language, narrative analysis Objavljeno v RUNG: 07.03.2016; Ogledov: 4429; Prenosov: 1 Gradivo ima več datotek! Več... |
5316. Narrative discourse in anomic aphasiaSara Andreetta, Anna Cantagallo, Andrea Marini, 2012, izvirni znanstveni članek Opis: Anomic aphasia is a disturbance affecting lexical retrieval. Nonetheless, persons with this disorder may also experience difficulties in the construction of coherent narratives. Whether this symptom is a sign of a macrolinguistic difficulty per se or reflects the lexical disorder is still an open debate. In order to analyze the effect of the lexical impairment on macrolinguistic processing, we compared the narrative skills of a group of ten participants with chronic anomic aphasia with those of ten healthy control individuals matched for age and educational level. The anomic participants produced narratives with lowered speech rate, reduced mean length of utterance, fewer grammatically well-formed sentences, more semantic paraphasias. The macrolinguistic analysis showed that they also produced more errors of cohesion and global coherence and fewer lexical information units. Interestingly, their levels of thematic selection were normal. A bivariate correlational analysis showed a strong correlation between the production of errors of cohesion and production of complete sentences, and between production of errors of global coherence and lexical information units. These correlations showed that aspects related to lexical retrieval may affect macrolinguistic processing during the construction of a narrative. Indeed, it is suggested that lexical deficits lead to two main consequences: First, patients with anomia frequently interrupt the utterances they are producing and this reduces the levels of sentence completeness and the overall degree of cohesion across the utterances; Second, they use strategies to cope with the lexical impairment and produce a quantity of lexical fillers and repetitions that, clustered in utterances, reduce the levels of global coherence. Ključne besede: aphasia, neurolinguistics, speech disorders, discourse analysis Objavljeno v RUNG: 07.03.2016; Ogledov: 4601; Prenosov: 0 Gradivo ima več datotek! Več... |
5317. Patterns of impairment of narrative language in mild traumatic brain injuryValentina Galetto, Sara Andreetta, Marina Zettin, Andrea Marini, 2013, izvirni znanstveni članek Opis: Mild traumatic brain injury (mTBI) represents a condition whose cognitive and behavioral sequelae are often underestimated, even when it exerts a profound impact on the patients’ every-day life. The present study aimed to analyze the features of narrative discourse impairment in a group of adults with mTBI. 10 mTBI non-aphasic speakers (GCS > 13) and 13 neurologically intact participants were recruited for the experiment. Their cognitive, linguistic and narrative skills were thoroughly assessed. The group of mTBIs exhibited normal phonological, lexical and grammatical skills. However, their narratives were characterized by the pres- ence of frequent interruptions of ongoing utterances, derailments and extraneous utterances that at times made their discourse vague and ambiguous. They produced more errors of global coherence [F (1; 21)1⁄424.242; p1⁄4.000; h2p1⁄40. 536] and fewer Lexical Information Units [F (1; 21) 1⁄4 7.068; p 1⁄4 .015; h2p 1⁄4 .252]. The errors of global coherence correlated negatively with non- perseverative errors on the WCST (r 1⁄4 1⁄4.755; p < .012). The mac- rolinguistic problems made their narrative samples less informa- tive than those produced by the group of control participants. These disturbances may reflect a deficit at the interface between cognitive and linguistic processing rather than a specific linguistic disturbance. These findings suggest that also persons with mild forms of TBI may experience linguistic disturbances that may hamper the quality of their every-day life. Ključne besede: mild traumatic brain injury, narrative analysis, neurolinguistics, neuropsychology Objavljeno v RUNG: 07.03.2016; Ogledov: 4812; Prenosov: 1 Gradivo ima več datotek! Več... |
5318. The effect of lexical deficits on narrative disturbances in fluent aphasiaSara Andreetta, Andrea Marini, 2015, izvirni znanstveni članek Opis: Background: The label “fluent aphasia” applies to different aphasic syndromes char- acterised by fluent speech with difficulties in lexical retrieval and/or grammatical processing.
Aims: This study aims at investigating microlinguistic and macrolinguistic skills in persons with fluent aphasia. We hypothesised that their lexical and syntactic (i.e., microlinguistic) difficulties would affect also their narrative (i.e., macrolinguistic) skills.
Methods & Procedures: Growing evidence shows that traditional tests may not be sensitive enough to capture the patterns of the linguistic impairments observed in these persons. Therefore, we used a narrative task to elicit linguistic samples. Spontaneous speech was elicited through a picture description task. The narrative samples were analysed with a multilevel approach that allows clinicians to quantify their productivity levels as well as their lexical, grammatical, and narrative skills. The spontaneous speech produced by a group of 20 persons with fluent aphasia was compared to that of a group of 20 healthy participants. All participants with aphasia were in the phase of neurological stability. The two groups were matched for age and level of formal education.
Outcomes & Results: Results showed that the lexical impairment observed in the group of participants with fluent aphasia hampered the ability to produce well-formed sentences that, in turn, lowered the levels of cohesion of their narrative samples. Furthermore, the reduced levels of lexical informativeness were found correlated also to the production of errors of global coherence.
Conclusions: These findings support the hypothesis that in these patients, microlin- guistic difficulties might affect macrolinguistic processing. Furthermore, these results stress the importance of a multilevel approach to assess linguistic skills in patients with fluent aphasia, as it assesses both microlinguistic and macrolinguistic dimensions in parallel. Therefore, it allows linguists, psychologists, and clinicians to observe how the linguistic levels interact during natural language processing. Ključne besede: neurolinguistics, aphasia, discourse analysis, coherence Objavljeno v RUNG: 07.03.2016; Ogledov: 4599; Prenosov: 0 Gradivo ima več datotek! Več... |
5319. |
5320. Education, Outreach and Public Relations of the Pierre Auger ObservatoryCharles Timmermans, Andrej Filipčič, Gašper Kukec Mezek, Ahmed Saleh, Samo Stanič, Marta Trini, Darko Veberič, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, 2015, objavljeni znanstveni prispevek na konferenci Opis: The scale and scope of the physics studied at the Pierre Auger
Observatory continue to offer significant opportunities for
original outreach work. Education, outreach and public
relations of the Auger Collaboration are coordinated in a
dedicated task whose goals are to encourage and support
a wide range of efforts that link schools and the public with
the Auger scientists and the science of cosmic rays, particle
physics, and associated technologies. We focus on the impact of
the Collaboration in Mendoza Province, Argentina and beyond.
The Auger Visitor Center in Malargüe has hosted over 95,000
visitors since 2001, and a fifth Collaboration-sponsored
science fair was held on the Observatory campus in November
2014. The Rural Schools Program, which is run by Observatory
staff and which brings cosmic-ray science and infrastructure
improvements to remote schools, continues to broaden its
reach. Numerous online resources, video documentaries, and
animations of extensive air showers have been created for wide
public release. Increasingly, collaborators draw on these
resources to develop Auger related displays and outreach events
at their institutions and in public settings to disseminate the
science and successes of the Observatory worldwide. We also
highlight education and outreach activities associated with the
planned upgrade of the Observatory’s detector systems and
future physics goals. Ključne besede: Pierre Auger Observatory, cosmic rays physics, education, outreach, public relations Objavljeno v RUNG: 03.03.2016; Ogledov: 4611; Prenosov: 184 Celotno besedilo (4,12 MB) |