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Artigo Acesso aberto Revisado por pares

Clara Isabel Koetz, John Daniel Tankersley,

... a netnographic study to examine the case of Caloi 10 on Facebook. The data collection was carried out ...

Tópico(s): Gender, Feminism, and Media

2016 - Emerald Publishing Limited | Journal of Business Strategy

Artigo Acesso aberto Revisado por pares

RONALD W. CLARK,

... al., let me point out that more than 10 years ago Caloi (Geophys.

Tópico(s): Philosophical Ethics and Theory

1972 - Nature Portfolio | Nature

Artigo Acesso aberto Revisado por pares

P. Caloi,

The results of geodynamic investigations, in a space of ten years (1953-1963) obtained in the Vajont's gorge during and after construction of the « Carlo Semenza » dam, they are here resumed. On their basis, it is examined the probable reasons of the October 9th 1963 tragic event. It is taken into consideration the seismic activity's awaking -towards the eastern zone of the dam- in the first ten days of September 1965 occurred.

Tópico(s): Dam Engineering and Safety

2011 - National Institute of Geophysics and Volcanology | Annals of Geophysics

Artigo Acesso aberto Revisado por pares

F. D’Antona, Vittoria Caloi,

Enhancement and spread of helium among globular cluster stars have been recently suggested as a way to explain the horizontal-branch blue tails in those clusters that show a primordial spread in the abundances of C, N, O, and other elements involved in advanced CNO burning. Helium enhancement is unavoidable if the matter responsible for the abundance spreads is identified with the matter lost by massive asymptotic giant branch stars, which evolve during the early phases of globular cluster life, ...

Tópico(s): Gamma-ray bursts and supernovae

2004 - IOP Publishing | The Astrophysical Journal

Artigo Acesso aberto

F. D’Antona, P. B. Stetson, P. Ventura, A. P. Milone, G. Piotto, V. Caloi,

The color magnitude diagram (CMD) of NGC 1851 presents two subgiant branches (SGB), probably due the presence of two populations differing in total CNO content. We test the idea that a difference in total CNO may simulate an age difference when comparing the CMD of clusters to derive relative ages. We compare NGC 1851 with NGC 6121 (M4), a cluster of very similar [Fe/H]. We find that, with a suitable shift of the CMDs that brings the two red horizontal branches at the same magnitude level, the unevolved ...

Tópico(s): Stellar, planetary, and galactic studies

2009 - Oxford University Press | Monthly Notices of the Royal Astronomical Society Letters

Artigo Acesso aberto Revisado por pares

P. Caloi,

New formulae for the determination of travel-times of seismic waves in the interior of the Earth. Applications of said formulae to the calculation of travel-times of ScS-waves, recorded with exceptional clearness at Tolmezzo, on occasion of Aegean Isles shallow earthquakes (1957 April–June). The problem of the waves reflected by the inner core: manifest examples of PKiKP-waves recorded at Tolmezzo.

Tópico(s): earthquake and tectonic studies

1961 - Oxford University Press | Geophysical Journal International

Artigo Revisado por pares

R. M. Caloi, Corrado Carretti,

In this article, starting from a calculation of the internal conductance inside AC and DC plasma display panels (PDPs), a simple theoretical model is used to estimate the pressure evolution inside a display during the exhausting process and the lifetime. All the values obtained are then compared to the results of specific measurements carried out on real PDPs. Based on these data, the role of a getter inside PDPs and possible getter configurations are discussed. According to the model proposed, the ...

Tópico(s): Electrostatic Discharge in Electronics

1998 - American Institute of Physics | Journal of Vacuum Science & Technology A Vacuum Surfaces and Films

Artigo Acesso aberto Revisado por pares

F. D’Antona, V. Caloi, I. Mazzitelli,

Chaboyer (1995) has recently shown that the range of possible ages of globular clusters, τ ~ 14-18 Gyr, corresponding to different choices of distance scales, is further enlarged mainly by uncertainties in modeling convection. Within the mixing-length theory (MLT) the result is τ = 11-21 Gyr. Bolte & Hogan (1995) adopted the field subdwarfs as indicators of the distance scale and, assuming that τ is insensitive to the treatment of convection, found that τ = (15.8 ± 2.1) Gyr. Within Chaboyer's findings, it is ...

Tópico(s): Gamma-ray bursts and supernovae

1997 - IOP Publishing | The Astrophysical Journal

Artigo Acesso aberto Revisado por pares

F. D’Antona, Vittoria Caloi, P. Ventura,

Core helium burning is the dominant source of energy of extreme horizontal branch stars, as the hydrogen envelope is too small to contribute to the nuclear energy output. The evolution of each mass in the HR diagram occurs along vertical tracks that, when the core helium is consumed, evolve to higher Teff and then to the white dwarf stage. The larger is the mass, the smaller is the Teff of the models, so that the zero age horizontal branch (ZAHB) is ‘horizontal’. In this paper we show that, if the ...

Tópico(s): Gamma-ray bursts and supernovae

2010 - Oxford University Press | Monthly Notices of the Royal Astronomical Society

Artigo Acesso aberto Revisado por pares

V. Caloi, F. D’Antona,

Inspection of the CM diagrams of globular clusters having similar heavy element content shows that the luminosity of the red giant bump relative to the turnoff () differs by more than 0.1 mag between clusters with different horizontal branch morphology. Unfortunately, careful consideration of the data leaves us with only one pair (M 3 and M 13) of clusters suitable for a quantitative discussion. For this pair we consider differences in age and helium content as possible causes for the difference in , ...

Tópico(s): Astro and Planetary Science

2005 - EDP Sciences | Astronomy and Astrophysics

Artigo Acesso aberto Revisado por pares

Vittoria Caloi, F. D’Antona,

The vast majority of globular clusters so far examined shows the chemical signatures of hosting (at least) two stellar populations. According to recent ideas, this feature requires a two-step process, in which the nuclearly processed matter from a 'first generation' (FG) of stars gives birth to a 'second generation' (SG), bearing the fingerprint of a fully carbon–nitrogen–oxygen (CNO) cycled matter. Since, as observed, the present population of most globular clusters is made up largely of SG stars, a ...

Tópico(s): Astro and Planetary Science

2011 - Oxford University Press | Monthly Notices of the Royal Astronomical Society

Capítulo de livro Revisado por pares

Domenico Patanè, O. Cocina, S. Falsaperla, E. Privitera, S. Spampinato,

... Sicily, Geophys. J. Int., 125, 857–868, 1996. 10.1111/j.1365-246X.1996.tb06029.x Web of Science®Google Scholar P. Caloi, A. Losurdo, G. Ponte, Agitazioni micro-sismiche originate da attività vulcanica, Ann. Geofis., 1, 5–9, 1948. Google Scholar C. Cardaci, S. Falsaperla, P. Gasperini, G. Lombardo, W. Marzocchi, F. Mulargia, Cross-Correlation analysis of seismic and volcanic data at Mt. Etna volcano, Italy, Bull. Volcanol., 55, 596–603, 1993. 10.1007/BF00301812 Web of Science®Google Scholar M. ...

Tópico(s): Seismology and Earthquake Studies

2004 - American Geophysical Union | Geophysical monograph

Artigo Revisado por pares

Lucía Caloi, María Rita Palombo,

Some cranial and mandibular characters, that are considered distinctive between grazers and browsers, are examined. Their analysis allows to recognize the exploiting of different feeding habits for every cervid. Attitude for grazing characterize the megacerine from Sardinia and the cervine from Sicily, while the megacerine from Sicily must have a browser diet. The feeding “niche” of the megacerine from Crete are difficult to identify. Analysis of the functional mophology of carpus, tarsus and phalanges ...

Tópico(s): Human-Animal Interaction Studies

1995 - Elsevier BV | Geobios

Artigo Acesso aberto Revisado por pares

P. Caloi,

né onde superficiali.

Tópico(s): Photovoltaic System Optimization Techniques

2012 - National Institute of Geophysics and Volcanology | Annals of Geophysics

Artigo Revisado por pares

G. Dattoli, L. Giannessi, L. Mezi, A. Torre, R. Caloi,

The FEL wave equation accounting for the longitudinal or/and transverse mode dynamics in the small-signal regime is reviewed within the context of a general operator approach to nonlocal integral-differential equations. The effects of the longitudinal and transverse variations of the optical field are accounted for by means of simple and easily definable parameters, which stand out as the counterpart of those defining the "quality" of the electron beam.

Tópico(s): Particle accelerators and beam dynamics

1991 - Elsevier BV | Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment

Artigo

G. Dattoli, A. Renieri, A. Torre, R. Caloi,

Tópico(s): Laser-Plasma Interactions and Diagnostics

1989 - Springer Nature | Il Nuovo Cimento D

Artigo Acesso aberto Revisado por pares

F. D’Antona, V. Caloi,

The majority of globular clusters show chemical inhomogeneities in the composition of their stars, apparently due to a second stellar generation in which the forming gas is enriched by hot-CNO cycled material processed in stars belonging to a first stellar generation. Clearly this evidence prompts questions on the modalities of formation of globular clusters. An important preliminary input to any model for the formation of multiple generations is to determine which is today the relative number fraction ...

Tópico(s): Astrophysics and Star Formation Studies

2008 - Oxford University Press | Monthly Notices of the Royal Astronomical Society

Artigo Revisado por pares

G. Dattoli, H. Fang, L. Giannessi, M. Richetta, A. Torre, R. Caloi,

In this paper we analyze an FEL operating in the moderate gain regime (0 < g0 < 10) and discuss the modification induced on the well-known antisymmetric gain formula by nonlinear contributions in the gain coefficient. The gain degradations due to e-beam energy spread and emittances are also included, as well as those due to finite electron pulse effects. Final comments on the attainable laser pulse length and bandwidth are also presented.

Tópico(s): Gyrotron and Vacuum Electronics Research

1989 - Elsevier BV | Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment

Artigo Acesso aberto Revisado por pares

P. Caloi,

.

Tópico(s): Geological and Geophysical Studies Worldwide

1952 - National Institute of Geophysics and Volcanology | Annals of Geophysics

Artigo Revisado por pares

Giacomo Santoiemma, Fabio Trivellato, Valentino Caloi, Nicola Mori, Lorenzo Marini,

Tópico(s): Insect-Plant Interactions and Control

2018 - Springer Science+Business Media | Journal of Pest Science

Artigo Revisado por pares

Lucía Caloi,

Equids are considered organisms indicating changes in climate and variations in environmental conditions. Within the Equini tribe, this sensitivity corresponds to a considerable morphological and physiological plasticity in the subgenus Equus, allowing its spread in Eurasia and North America under the most adverse and diversified climatical conditions. Also the stenonian species, E. stenonis, show a certain plasticity, and in their vast territory in North America and Eurasia have led to a variety ...

Tópico(s): Ecology and biodiversity studies

1997 - Elsevier BV | Geobios

Artigo Revisado por pares

R. Bonifacio, R. Caloi, C. Maroli,

Abstract The limit of validity of the slowly varying envelope approximation (SVEA) is derived as a function of the “bulk” velocity v of the radiating system, which reads l p ⪢λ(1− v/c ), l p being the radiation pulse length. This condition reduces to the usual SVEA in the limit v/c ⪡ 1, whereas it is sensibly relaxed in the relativistic limit. The relevance for the case of microwave free electron lasers is discussed.

Tópico(s): Particle accelerators and beam dynamics

1993 - Elsevier BV | Optics Communications

Artigo Acesso aberto Revisado por pares

F. D’Antona, V. Caloi, J. Montalbán, P. Ventura, R. Gratton,

It is becoming clear that `self--pollution' by the ejecta of massive asymptotic giant branch stars has an important role in the early chemical evolution of globular cluster stars, producing CNO abundance spreads which are observed also at the surface of unevolved stars. Considering that the ejecta which are CNO processed must also be helium enriched, we have modelled stellar evolution of globular cluster stars by taking into account this possible helium enhancement with respect to the primordial ...

Tópico(s): Astro and Planetary Science

2002 - EDP Sciences | Astronomy and Astrophysics

Artigo Revisado por pares

Lucía Caloi, María Rita Palombo,

Abstract The endemic herbivores of Pleistocene Mediterranean Islands, in their processes of adaptation and speciation, show two main tendencies: size variations, widely described in the case of size reduction, and morphological and functional variations, mainly concerning the distal segment of limbs. In the so‐called pachyderms (elephants and hippos) adaptive morphologies are added to variations due to size reduction and point out a cursorial attitude. The endemic insular cervids show perhaps less ...

Tópico(s): Wildlife Ecology and Conservation

1994 - Taylor & Francis | Historical Biology

Artigo

G. Dattoli, A. Torre, R. Caloi,

In this paper we exploit the Wei-Norman algebraic disentangling procedure to study the evolution of quantum states driven by a time-dependent Hamiltonian linear combination of the generators of the SU(1,1) group.

Tópico(s): Quantum Mechanics and Applications

1986 - American Institute of Physics | Physical review. A, General physics

Artigo Acesso aberto Revisado por pares

V. Caloi,

We investigate the consequences of an increase in the envelope helium abundance of pre-helium flash red giants in globular clusters, an occurrence suggested by chemical peculiarities in many red giant atmospheres. Comparing predictions with the CM diagrams of a few crucial globular clusters, one finds no evidence for a substantial increase in the surface helium content of horizontal branch members of these clusters, at least for objects in the RR Lyrae region or close to it. The possibility that ...

Tópico(s): Astro and Planetary Science

2001 - EDP Sciences | Astronomy and Astrophysics

Artigo Acesso aberto Revisado por pares

P. Caloi,

.

1957 - National Institute of Geophysics and Volcanology | Annals of Geophysics

Artigo Acesso aberto Revisado por pares

M. Tailo, M. Di Criscienzo, F. D’Antona, V. Caloi, P. Ventura,

We interpret the stellar population of ω Centauri by means of a population synthesis analysis, following the most recent observational guidelines for input metallicities, helium and [(C+N+O)/Fe] contents. We deal at the same time with the main sequences, sub-giant and horizontal branch (HB) data. The reproduction of the observed colour–magnitude features is very satisfying and bears interesting hints concerning the evolutionary history of this peculiar stellar ensemble. Our main results are: (1) no ...

Tópico(s): Astronomy and Astrophysical Research

2016 - Oxford University Press | Monthly Notices of the Royal Astronomical Society

Artigo Acesso aberto Revisado por pares

V. Caloi, F. D’Antona,

Context.The metal-rich bulge globular cluster NGC 6441 shows both a well-developed blue horizontal branch (Rich et al.), and a strong slope upward from the red clump to the blue of the RR Lyrae region. The former corresponds to the well–known second parameter problem. Both features are not explained by conventional evolutionary models.

Tópico(s): Astrophysics and Star Formation Studies

2006 - EDP Sciences | Astronomy and Astrophysics