1,721,069 research outputs found
Sen's mechanism for self-dual super Maxwell theory
Full text linkIn several elementary particle scenarios, self-dual fields emerge as fundamental degrees of freedom. Some examples are the D=2 chiral boson, D=10 Type IIB supergravity, and D=6 chiral tensor multiplet theory. For those models, a novel variational principle has been proposed in the work of Ashoke Sen. The coupling to supergravity of self-dual models in that new framework is rather peculiar to guarantee the decoupling of unphysical degrees of freedom. We generalize this technique to the self-dual super Maxwell gauge theory in D=4 Euclidean spacetime both in the component formalism and the superspace. We use the geometric tools of rheonomy and integral forms since they are very powerful geometrical techniques for the extension to supergravity. We show the equivalence between the two formulations by choosing a different integral form defined using a Picture Changing Operator. That leads to a meaningful action functional for the variational equations. In addition, we couple the model to a non-dynamical gravitino to extend the analysis slightly beyond the free case. A full-fledged self-dual supergravity analysis will be presented elsewhere
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
Microsurgical Disconnection of Ruptured Intracranial Pial Arteriovenous Fistula Guided by Indocyanine Green Videoangiography
No full textIntracranial arteriovenous fistulas, rare causes of spontaneous intracerebral bleeding, are direct communications between an arterial feeder and an arterialized vein that drains a normal brain. Arteriovenous disconnection is the only effective treatment for this type of vascular malformation, which is often reached microsurgically due to the difficult endovascular access. Intraoperative indocyanine green videoangiography (ICG-VA) is a valuable help in identifying the arterialized draining vein and its direct communication with the arterial feeder and in confirming real-time interruption of the fistula. We describe the case of a 46-year-old man presenting with sudden onset of headache and left arm motor and sensory deficits associated with a frontoparietal hematoma evacuated 1 week earlier in another institution. Digital subtraction angiography showed a direct communication between an anterior parietal branch of the right middle cerebral artery and a parietal vein. Given the difficulty to reach the point of the fistula endovascularly because of the small caliber and tortuosity of the arterial feeder, as well as the short and relatively rapid flow through the arteriovenous communication, we decided to proceed with microsurgical treatment. Under intraoperative neurophysiologic monitoring the fistula was located with the aid of ICG-VA and interrupted (Video 1). Both control ICG-VA and postoperative angiogram confirmed resolution of the fistula. At a 3-month follow-up the patient had a complete neurologic recovery
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Positioning on surgical table
No full textPositioning on the surgical table is one of the most important steps in any spinal surgical procedure. The "prone position" has traditionally been and remains the most common position used to access the dorsolumbar-sacral spine. Over the years, several authors have focused their attention on the anatomy and pathophysiology of both the vascular system and ventilation in order to reduce the amount of venous bleeding, as well as to prevent other complications and facilitate safe posterior approaches. The present paper reviews the pertinent literature with the aim of highlighting the advantages and disadvantages of various frames and positions currently used in posterior spinal surgery
Regression of Benedikt's syndrome after single-stage removal of mesencephalic cavernoma and temporal meningioma: A case report
No full textAnsonica
No full textDalla descrizione di Breviglieri et al., (1965) si rileva che Alessio e Dalmasso, riferiscono quanto segue riguardo all’origine del vitigno Ansonica (Ansoria, Inzolia): L'italiano antico (sec. XVI) conosce la voce «ansoria» ad indicare una specie di uva, voce che appare registrata anche dai dizionari del Petrocchi e Tommaso Bellini. Il vocabolo sembra di origine meridionale ed è tuttora presente in: - Sicilia: sòria, (n)zòlia, nsolia (sorta di uva grossa, dolce, di acini bislunghi); - Calabria: ansòlia, nsuòlia, insòlia, anzulu, ansoliku, ansoria, specie di uva bianca; - Sardegna: erba insòlika, arba sòlika (da albus ’bianco‘)varietà di vite a frutto bianco; - Toscana: isola d'Elb (ansòniko, sorta d'uva bianca che fa un vino dello stesso nome; isola del Giglio, anzònaka (una qualità di uva), anzònako (il vino che deriva). Delle voci sopracitate, ansoria è quella attestata più anticamente.
Questo vitigno è stato descritto in passato da molti Autori, come risulta dalla bibliografia riportata dal Molon.
Nel Catalogo dell’Hortus Catholicus del Cupani (1696) risultano tre tipi di «Inzolia», di cui due a frutto bianco: “Vitis mediocribus vinaceis, durulis, oblongis, candido-fulvis, sapidis, vulgo: Inzolia Vranca, Eadem racemo, et granis majoribus; flavescentibus, sapidioribus, vulgo: Inzolia Imperiali o di Napuli”. L’Acerbi (1825) riportò una breve descrizione del vitigno denominato «Nzolia bianca» ad acino oblungo. Il barone Mendola (1868) a proposito dell’ “Insolia bianca” scrisse: Le “Insolie’” sono coltivate “ab antico” in Sicilia. Hanno comune vigore di legno, copia e robustezza di capreoli, fogliame frastagliato. La più feconda e mostaia è la bianca dorata che pur piace alla bocca e abbonda in tutti i vigneti da Marsala a Catania.
Il Nicolosi (1869) la definì “bellissima qualità di uva, dà molto frutto e fa vino generoso, è di sapore gentile; pregi che la rendono molto ricercata”.
Il Paulsen (1904) nella sua monografia dette anche dettagliate notizie sul suo comportamento all’innesto con i portinnesti americani.
L’origine siciliana di questa varietà è la più accreditata, nonostante il Soderini (1590) riporti tra le varietà coltivate in Toscana le Ansorie ed il Cupani le descriva circa 90 anni più tardi (1696). Giavedoni e Gily (2006) affermano che l’Insolia ha le sue radici in Sicilia e che da qui sia arrivata in Sardegna prima e nell’Isola d’Elba e del Giglio dopo e alla zona costiera della Toscana.
Altre ipotesi che considerano l’Inzolia identica all’Irziola citata da Plinio e per questo di origine greca, presenta peraltro un profilo genetico simile alle varietà greche Sideritis e Roditis (Labra et al. 1999). L’origine siciliana di questo vitigno è supportata anche dallo studio etimologico di Dalmasso e Alessio (1938) che dimostrano l’origine normanna del nome del vitigno “racina soria” che indica uva di colore dorato e da questa del vitigno che la produce. Ulteriore conferma dell’origine siciliana del vitigno scaturisce dal lavoro di Carimi et al., (2010) dove si evidenzia una stretta relazione genetica dell’Inzolia con molti vitigni tradizionali della Sicilia (Frappato, Grillo, Moscato giallo o Muscatedda e Nerello Mascalese). L’Acerbi, il Cupani, il Di Rovasenda e il Mendola sotto il nome Inzolia riportano diverse varietà riconducibili all’Inzolia bianca e nera e all’Inzolia imperiale bianca e nera, che peraltro assumono nomi diversi nelle differenti province e aree di coltivazione. Recenti studi (Carimi, l.c.) hanno dimostrato che l’Inzolia nera non è una mutazione di quella bianca e che le Inzolie Imperiali sono diverse dall’Inzolia ma identiche alla varietà Regina (Robinson et al., 2012
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