1,721,100 research outputs found
A new kind of selectors and their applications to conflict resolution in wireless multichannels networks
No full textWe investigate the benefits of using multiple channels in wireless networks, under the full-duplex multi-packet reception model of communication. The main question we address is the following: Is a speedup linear in the number of channels available, for some interesting communication primitive? We provide a positive answer to this interrogative for the Information Exchange Problem, in which up to k arbitrary nodes have information they intend to share with the entire network. In particular, we give non-adaptive deterministic protocols for both the scenario in which the channels provide the transmitting stations with the feedback on whether their transmissions have been successful and for the scenario in which channels provide no such feedback. To this aim, we devise and exploit a new combinatorial structure that generalizes well known combinatorial tools, widely used in the area of data-exchange in multiple-access channels (i.e., strongly selective families, selectors, and related mathematical objects). For our new combinatorial structures we provide both existential results and randomized algorithms to generate them. We also prove non-existence results showing that our protocol for the model with feedback is optimal, whereas that for the no-feedback scenario uses a number of time slots that exceeds the lower bound by a logk factor. Leveraging on properties of error correcting codes, we show that for an infinite set of the relevant parameters n and k, one can construct our combinatorial structure for the no-feedback scenario in polynomial time and of minimum length
Is it appropriate to use EuroSCORE II for prediction of 30-day mortality in cardiac surgery? Reply
No full textL’integrazione dei migranti maghrebini in Veneto
No full textTesto contenuto in: CNR-Istituto di Ricerche sulla Popolazione e le Politiche Sociali, L’inserimento lavorativo e l’integrazione sociale dei maghrebini in Italia, Roma,
autore delle seguenti parti
Gli immigrati maghrebini in Veneto. Radicamento, precarizzazione, resistenza, selezione
No full textRicerca multiregionale promossa dall’Organizzazione Internazionale delle Migrazioni – sede di Roma
The labour dimension of racial discrimination in Italy: 2004 Report
No full textReport commissioned by Cospe of Florence, national coordinator of the Raxen Project promoted and financied by European Monitoring Centre on Racism and Xenophobia of Wien
Mimicking focal epileptic seizures-episodic pain due to a facial foreign body in a puppy: Imaging characteristics and treatment
No full textA 4-month-old female entire Cavalier King Charles Spaniel was referred for investigation into a 3-week history of suspected focal onset seizures, characterised by head nodding and eyelid twitching. An inflammatory soft-tissue reaction surrounding a suspected foreign body (FB) in the subcutaneous tissue and muscles at the level of the left maxilla in the caudal aspect of the left maxillary second molar was detected using MRI. The presence of the FB was confirmed ultrasonographically. This was found to be a grass seed upon surgical removal. The previously reported clinical signs resolved immediately after the surgery. It was suspected that the FB and secondary inflammatory reaction incited a form of trigeminal neuralgia manifesting as paroxysmal head nodding and facial twitching. A form of trigeminal neuralgia should be included in the differential diagnosis of facial focal motor seizures and should be investigated accordingly before initiating any antiepileptic treatment
Raw materials for ancient ceramic productions from Campania region: provenance studies by means of Sr-Nd isotopes
No full textWhen archaeometric studies on archaeological ceramics are performed, one of the most important questions
asked by archaeologists is the provenance of pottery. This is usually performed by comparing mineropetrographic
and chemical composition of ceramics with that of local raw materials (clays, temper), production
indicators and appropriate reference groups. Nevertheless, the commonly-used analytical techniques (e.g. OM,
SEM-EDS, XRF, ICP-MS) may not always be helpful for the determination of provenance. Indeed, processing
of raw materials, such as tempering or levigation, can significantly modify their original chemical composition,
sometimes leading to an ineffective identification of raw material resources. For this reason, a pioneering
analytical approach has been recently applied by measuring the Sr and Nd isotopic signature.
Isotope analysis has largely used in archaeological sciences to date objects and identify their provenance,
making it also a useful tool for the determination of provenance of ceramic vessels (De Bonis et al., 2018 and
references therein). For this study, 87Sr/86Sr and 143Nd/144Nd isotope ratios were measured on archaeological
pottery from Campania and raw materials (clays and volcanic temper) exploited in antiquity for producing
ceramics. The analyses were focused on samples from both the Bay of Naples and Southern Campania. The
isotope signatures allowed us to better discriminate among different productions and find a strong relationship
between the archaeological pottery and the geological sources of raw materials.
In order to validate the method, Sr-Nd isotope ratios were also measured for the first time on experimental
ceramic materials that replicate archaeological pottery (De Bonis et al., 2018). It was interesting to note that
synthetic mixtures used for the ceramic replicas plot exactly on the theoretical mixing curve between the
clay and volcanic temper end-members. This suggests that the artificial manipulation of raw materials (firing,
levigation, tempering) induces no significant variations to the Sr-Nd isotope fingerprint, which strictly depends
on the geochemical affinity of the raw materials. Thus, isotopic analysis can be considered as an effective
and robust method that could complement the common multi-analytical approach in order to more precisely
constrain potential geological sources for ceramic materials and pottery provenance.
De Bonis, A., Arienzo I., D’Antonio, M., Franciosi, L., Germinario, C., Grifa, C., Guarino, V., Langella, A. & Morra, V.
(2018): Sr-Nd isotopic fingerprint as a tool for ceramic provenance: application on raw materials, ceramic replicas and
ancient pottery. J. Archaeol. Sci., 94, 51-59
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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