112,063 research outputs found
Xenochironomus Fusari, Roque & Hamada, 2013, sp. n.
No full textKey to the pupae of Xenochironomus 1. Tergites II–V with bands in the median region with black shagreen.................. Xenochironomus xenolabis (Kieffer) - Tergites II–V with anterior bands of brown shagreen.......................................................... 2 2. Sternites I and II with posterior bands of clear spines.......................................................... 3 - Sternites I and II without spines.................................................... Xenochironomus grini sp. n. 3. Pedes spurii A present in segment IV...................................................................... 4 - Pedes spurii A absent in segment IV.................................... Xenochironomus canterburyensis (Freeman) 4. Prealar tubercle present........................................ Xenochironomus ceciliae Roque et Trivinho-Strixino - Prealar tubercle absent........................................................ Xenochironomus mendesi sp. n. Key to the fourth-instar larvae of Xenochironomus 1. Labral sclerite 1 divided into two plates........................................ Xenochironomus xenolabis (Kieffer) - Labral sclerite 1 undivided.............................................................................. 2 2. Mentum with even number of teeth....................................................................... 3 - Mentum with odd number of teeth........................................................................ 4 3. Mentum with 12 teeth............................................................ Xenochironomus grini sp. n. - Mentum with 16 teeth......................................................... Xenochironomus mendesi sp. n. 4. Median tooth of the mentum sutured.................................. Xenochironomus canterburyensis (Freeman) * - Median tooth of the mentum simple............................. Xenochironomus ceciliae Roque et Trivinho-StrixinoPublished as part of Fusari, Lívia Maria, Roque, Fabio De Oliveira & Hamada, Neusa, 2013, Review of Xenochironomus Kieffer, 1921 (Diptera: Chironomidae) with description of six new species, pp. 101-126 in Zootaxa 3646 (2) on pages 123-124, DOI: 10.11646/zootaxa.3646.2.1, http://zenodo.org/record/21950
Anglicisms in the discourse of Alitalia's bailout in the Italian press
No full textThe chapter describes a corpus study of the Anglicisms and false Anglicisms used by two major Italian newspapers (Repubblica and Corriere della Sera) in their representation of the bailout and privatization of the Italian airline Alitalia. The aim is to establish if and to what extent the use of new non-adapted Anglicisms in news reports of Alitalia’s crisis and privatization, especially in the domains of economics and aviation, had an impact on the transparency of the information provided. The results show that, in the coverage of this news story, new Anglicisms are often left undefined, or provided with an inappropriate Italian equivalent. This may make it more difficult for readers to develop a thorough understanding of Alitalia’s crisis and privatization
Continuous wave and modelocked femtosecond novel bulk glass lasers operating around 2000 nm
No full textThis thesis reports on the development of glass-based femtosecond laser sources around 2 µm wavelength. In order to be able to produce 2 µm radiation the dopants used were trivalent Thulium (Tm³⁺) and trivalent Holmium (Ho³⁺) that could be optically pumped with Ti:Sapphire radiation at 0.8 µm and semiconductor disk lasers (SDL) at 1.2 µm. The samples were produced at Leeds University and polished in-house in bulk form and deployed in free space laser cavities.
Tellurite compounds doped with Tm³⁺ produced stable continuous wave 1.94 µm radiation when pumped at 800 nm with a maximum efficiency of 28.4% with respect to the absorbed power and maximum output power around 120 mW when pumped using a Ti:Sapphire operating around 0.8 µm. The radiation was broadly tunable across 130 nm. Tm³⁺-Ho³⁺ doubly doped tellurite samples lased around 2.02 µm with maximum efficiency of 25.9% and with P[subscript(OUT)]=75 mW and a smooth tunability of 125 nm.
The fluorogermanate glass doped with Tm³⁺ gave an absorbed to output power efficiency of 50%. The maximum continuous wave output powers obtained were around 190 mW and limited by the available pump power at 0.8 µm. These results together with a very low threshold of 60 mW of incident power were comparable to the crystalline counterparts to this gain medium.
The Tm3+ tellurite and the Tm³⁺-Ho³⁺ tellurite compounds were also pumped by an SDL operating at 1215 nm to obtain an indication of the viability of such a pump scheme. The results were a maximum internal slope efficiency of 22.4% with a highest output power of 60 mW. The comparison demonstrated that 1.2 µm pumping was competitive with using 0.8 µm wavelength.
The use of semiconductor saturable absorbing mirror (SESAM) technology was used for the modelocking of these lasers. The SESAM was produced in Canada and implanted with As⁺ ions in order to reduce the relaxation time.
Trains of transform-limited laser pulses at 222 MHz as short as 410 fs centred at 1.99 µm were produced for the first time with a bulk Tm³⁺:Fluorogermanate glass. The maximum average output power obtained was of 84 mW. The same SESAM deployed on the Tm³⁺-Ho³⁺ Tellurite compounds gave trains of transform-limited pulses as short as 630 fs at 2.01 µm with a repetition rate of 143 MHz and a maximum averaged output power of 43 mW. The regime of propagation obtained was soliton-like and the modelocking was self-starting. The results obtained with bulk glass were very promising and open interesting research pathways within the realm of amorphous bulk gain media
Diamo rifugio ai talenti. Nuove forme di inclusione e internazionalizzazione attraverso l’Università di Pavia
No full textAfrica e Europa allo specchio: contesti e pretesti della mobilità circolare
No full textIl tema delle migrazioni circolari ricorre oggi frequentemente all’interno del più ampio dibattito sulla necessità, da parte dell’Unione Europea, di sviluppare una comune governance del fenomeno delle migrazioni internazionali. Pur partendo dalla lettura che gli organi dell’Unione fanno di questo particolare modello di mobilità, indicandolo come cruciale nelle strategie per lo sviluppo dei Paesi di origine e per il controllo delle migrazioni illegali, questo contributo intende offrire profondità storica e culturale alla discussione sulla migrazione circolare, privilegiando un approccio “olistico”, teso a superare le posizioni eurocentriche e schiacciate sul presente e inglobando le esperienze passate e presenti dell’Africa sub-sahariana. Pertanto nella prima parte di questo lavoro, dopo una definizione di “migrazione circolare”, ripercorreremo i momenti in cui le migrazioni circolari hanno assunto maggiore rilevanza all’interno del discorso europeo sulle migrazioni, fino ad arrivare alle proposte più recenti in materia di politiche migratorie, dove occupano definitivamente un ruolo di primo piano. Al termine di questa sezione introduttiva, proveremo a mettere in evidenza alcuni aspetti critici e questioni aperte circa l’efficacia delle politiche che si basano su questo modello. La seconda parte del contributo presenta la prassi e il razionale della migrazione circolare in Africa sub-sahariana e nel Corno d’Africa nello specifico, mettendone poi in luce le difficoltà di rilevazione e mostrando come la logica demografica nei programmi di migrazione circolare Africa-Europa permanga ormai da quasi un secolo alla base delle politiche migratorie proposte nel corso del tempo. Infine, si pone l’accento sulla relazione fra sviluppo e migrazioni che oggi pare dominare il dibattito scientifico e mediatico
Investigating complex noun–noun modification in academic prose
No full textUnderstanding and using nominalized structures is a fundamental skill for advanced TESOL students, especially in academic settings. This lesson encourages students to experiment with the structure of the noun group in academic English with a special focus on its potential complexity (e.g. job satisfaction vs. community college faculty job satisfaction). This can be done by looking at how the noun group “can be expanded to a more or less indefinite extent” (Halliday, 1998, p. 196) by adding other nouns before (pre-modification) and after it (post-modification). Working with grammatical tags in the Corpus of Contemporary American English (COCA), students are encouraged to reason in terms of the mechanism whereby the idea expressed by a central noun can be specified and/or expanded
Lettere di carta, parole per convincere
No full textL'articolo illustra, con un approccio divulgativo, i risultati di una ricerca svolta con l'ausilio di corpora informatici per lo studio delle parole chiave maggiormente utilizzate in italiano nel discorso della raccolta fondi per le organizzazioni nonprofit. Lo scopo è mettere a conoscenza gli operatori del settore dei risultati dello studio, onde fornire loro strumenti operativi per la loro professione (in particolare per la professione di fundraiser). Viene altresì operato un paragone con il linguaggio della raccolta fondi utilizzato in ambito statunitense
Introduction. The fear of big numbers: the politics and politicisation of African demographic change
No full textSince the beginning of the 2000s, scientific research and studies by international organi-sations have converged in identifying new major trends in African demography for the de-cades to come, contributing to reshape the public representations of Africa from a low pop-ulation continent to one of rampant growth. At the same time, the public discourse emerged in the West regarding these changes occurred under the sign of a dramatised politicisation rather than a scientifically based debate. Under the pressure of the recent “migration crisis” in Europe, this politicised Euro-African demography has set itself at the centre of public and media debates in many European nations, based on alarming demographic predictions that oppose a succumbing “old Europe” to an emerging “young Africa”. Against this back-ground, the goal of this introduction is twofold: outlining a history of concepts and ideas pertaining to African demography in its political dimension; identifying spaces for dialogue and cooperation between different disciplines and reconsider epistemological and method-ological conventions with the goal of responding to the challenges of the politicization of African demographic dynamics
Etno-demografia e religione
No full textIl testo rappresenta una prima riflessione sull'interazione e l'impatto esistente fra fenomeni demografici e religione, prestando particolare attenzione a all'influenza, oltre che sulla creazione di fonti demografiche, su fecondità, nuzialità, migrazioni e mortalità
Unreliability of Depopulated Bovine Ureteric Xenograft for Infra Inguinal Bypass Surgery: Mid-term Results from Two Vascular Centres
No full textIntroductionWe report a two centre experience with a depopulated ureteric xenograft (SGVG 100®, CryoLife Inc., GA, USA) for femoropopliteal revascularization in 12 patients with chronic critical limb ischemia.ReportBetween 7 days and 18 months after implantation, 10 of 12 patients (1 lost to follow-up) had the graft explanted due to aneurysmal enlargement. At 5 years, only one graft was still patent and showed moderate signs of enlargement.ConclusionThe SGVG 100® is not a safe conduit for femoropopliteal bypass surgery
- …
