Responsabilità e merito nel mondo antico. Retorica, Giustizia, Società. Atti del Convegno di Palermo, 10-11 febbraio 2016

"Merit and Responsability. A Study in Greek Values" è il titolo di un volume pubblicato ormai cinquant’anni or sono da W.H. Adkins. L’autore metteva in evidenza il mancato sviluppo, nel mondo greco, del concetto di responsabilità morale a vantaggio della nozione di arete, postulando la distanza irriducibile tra l’etica greca e quella contemporanea. Quelle di responsabilità e merito sono in effetti categorie su cui la cultura contemporanea si è notevolmente esercitata e continua a interrogarsi, soprattutto in questi anni caratterizzati da un sentimento di incertezza in tutti gli aspetti della nostra esistenza e in particolare nell’agire quotidiano e nelle relazioni sociali. E tuttavia si tratta di un insieme di riflessioni su cui il pensiero antico molto ha ancora da dirci, spesso con una complessità e una sensibilità sorprendenti

Presentazione

Introduzione agli atti del convegno Responsabilit\ue0 e merito nel mondo antico. Retorica, Giustizia, Societ\ue0 (Palermo, 10-11 febbraio 2016)Introduction to the proceedings of the conference "Responsibility and Merit in the Ancient World. Rhetoric, Justice, Society (Palermo, 10-11 February

Responsabilit\ue0 e merito nel mondo antico. Retorica, Giustizia, Societ\ue0. Atti del Convegno di Palermo, 10-11 febbraio 2016

"Merit and Responsability. A Study in Greek Values" \ue8 il titolo di un volume pubblicato ormai cinquant\u2019anni or sono da W.H. Adkins. L\u2019autore metteva in evidenza il mancato sviluppo, nel mondo greco, del concetto di responsabilit\ue0 morale a vantaggio della nozione di arete, postulando la distanza irriducibile tra l\u2019etica greca e quella contemporanea. Quelle di responsabilit\ue0 e merito sono in effetti categorie su cui la cultura contemporanea si \ue8 notevolmente esercitata e continua a interrogarsi, soprattutto in questi anni caratterizzati da un sentimento di incertezza in tutti gli aspetti della nostra esistenza e in particolare nell\u2019agire quotidiano e nelle relazioni sociali. E tuttavia si tratta di un insieme di riflessioni su cui il pensiero antico molto ha ancora da dirci, spesso con una complessit\ue0 e una sensibilit\ue0 sorprendenti

Semiochemical exploitation of host-associated cues by seven Melittobia parasitoid species: Behavioral and phylogenetic implications

Chemical compounds (infochemicals or semiochemicals) play an important role both in intra-specific and inter-specific communication. For example, chemical cues appear to play a key role in the host selection process adopted by insect parasitoids. In recent years significant advances have been made in order to understand the chemical ecology of insect parasitoids. However, little information is available about the evolution of semiochemical use in the host location process of insect parasitoids. Here we investigated the strategy adopted by seven closely related parasitoid species in the genus Melittobia when foraging for four different suitable hosts. By using an integrated approach that combined olfactometer bioassays and phylogenetic investigations, we found that: (1) exploitation of host-derived semiochemicals is widespread in the Melittobia genus; (2) there is specificity of attraction toward the different host species tested; in particular, the early-branching species in the Melittobia genus are attracted to odors associated with leaf cutting bees (Megachile rotundata) whereas the most-diverged species are attracted to odors associated with solitary mud dauber wasps (Trypoxyilon politum). Regardless of the phylogenetic relationships, no Melittobia species exhibited attraction toward odors of factitious laboratory hosts (i.e., the flesh fly Sarcophaga bullata). Interestingly, five Melittobia species are also attracted by odors associated with honeybees hosts which indicate that these parasitoids could be potential pests of honeybees. Our study shed light on the host location within the Melittobia genus and represents a first attempt to understand semiochemical use in an evolutionary perspective in the context of parasitoids' foraging behavior

Testing the gamma-ray burst variability/peak luminosity correlation on a Swift homogeneous sample

We test the gamma-ray burst correlation between temporal variability and peak luminosity of the $\gamma$-ray profile on a homogeneous sample of 36 Swift/BAT GRBs with firm redshift determination. This is the first time that this correlation can be tested on a homogeneous data sample. The correlation is confirmed, as long as the 6 GRBs with low luminosity (<5x10^{50} erg s^{-1} in the rest-frame 100-1000 keV energy band) are ignored. We confirm that the considerable scatter of the correlation already known is not due to the combination of data from different instruments with different energy bands, but it is intrinsic to the correlation itself. Thanks to the unprecedented sensitivity of Swift/BAT, the variability/peak luminosity correlation is tested on low-luminosity GRBs. Our results show that these GRBs are definite outliers.Comment: Accepted for Publication in MNRAS. 10 pages, 5 figures, 3 table

BeppoSAX observation of the X-ray binary pulsar Vela X-1

We report on the spectral (pulse averaged) and timing analysis of the ~ 20 ksec observation of the X-ray binary pulsar Vela X-1 performed during the BeppoSAX Science Verification Phase. The source was observed in two different intensity states: the low state is probably due to an erratic intensity dip and shows a decrease of a factor ~ 2 in intensity, and a factor 10 in Nh. We have not been able to fit the 2-100 keV continuum spectrum with the standard (for an X--ray pulsar) power law modified by a high energy cutoff because of the flattening of the spectrum in ~ 10-30 keV. The timing analysis confirms previous results: the pulse profile changes from a five-peak structure for energies less than 15 keV, to a simpler two-peak shape at higher energies. The Fourier analysis shows a very complex harmonic component: up to 23 harmonics are clearly visible in the power spectrum, with a dominant first harmonic for low energy data, and a second one as the more prominent for energies greater than 15 keV. The aperiodic component in the Vela X-1 power spectrum presents a knee at about 1 Hz. The pulse period, corrected for binary motion, is 283.206 +/- 0.001 sec.Comment: 5 pages, 4 PostScript figure, uses aipproc.sty, to appear in Proceedings of Fourth Compton Symposiu