A wavelet-based method to measure the toroidal mode number of ELMs

The high confinement mode regime (H-mode) in tokamaks is accompanied by the occurrence of burst of MHD activity at the plasma edge, so-called edge localized modes (ELMs). Because of the short time scales involved in the ELM crash (on JET typically 0.2 ms), standard Fourier analysis can hardly be used to extract their toroidal mode number. On the other hand, the assessment of linear stability of ELMs with the ion drift effects included, makes the identification of their toroidal mode numbers an important issue, while an accurate comparison with the theory of nonlinear evolution of ELMs requires the knowledge of the nonlinear spectrum. Compared to Fourier analysis, wavelets are suitable to study transient events on time scales comparable to the wave period. Spectral analysis based on sinusoidal wavelet functions has been applied to study the spectral properties of magnetic perturbations associated with ELMs and with their precursors, in JET plasmas with toroidal rotation driven by unbalanced NBI. It is shown that, combining wavelet analysis with statistical two-point correlation techniques, it is possible to get information on the toroidal mode number structure of magnetic perturbations during the phases that immediately precede the ELM and during the ELM crash itself

Cancerogenic parasites in veterinary medicine: a narrative literature review

Parasite infection is one of the many environmental factors that can significantly contribute to carcinogenesis and is already known to be associated with a variety of malignancies in both human and veterinary medicine. However, the actual number of cancerogenic parasites and their relationship to tumor development is far from being fully understood, especially in veterinary medicine. Thus, the aim of this review is to investigate parasite-related cancers in domestic and wild animals and their burden in veterinary oncology. Spontaneous neoplasia with ascertained or putative parasite etiology in domestic and wild animals will be reviewed, and the multifarious mechanisms of protozoan and metazoan cancer induction will be discussed

Adverb + adjective collocations in a spoken learner corpus: A quantitative and qualitative approach

Negli ultimi 70 anni, c'è stato un incremento degli studi e ricerche inglesi sulle collocazioni (Firth 1957; Hoey, 2005; Moon, 1998b; Sinclair 1991; 2004; Stubbs, 1996; 2001), i quali hanno evidenziato che la fraseologia è pervasiva alla lingua (Altenberg, 1998; Biber et al., 1999; Cowie, 1991; 1992; Howarth; 1998). Questo indica anche che una buona padronanza delle collocazioni è necessaria se i discenti mirano a raggiungere una fluidità simile a quella di un nativo nella L2. Infatti, la ricerca sulla produzione di linguaggio formulaico da parte degli apprendenti ha dimostrato che le collocazioni sono essenziali nell'acquisizione della lingua seconda (Cowie, 1998; Pawley & Syder, 1983; Peters, 1983) e sono una componente chiave per lo sviluppo della "fluency" (Ellis, 2002; 2003; Ellis et al., 2015; Howarth, 1998). Nonostante il maggior numero di studi sulle collocazioni, la maggior parte degli studiosi si è concentrata su dati scritti e su un insieme ristretto di combinazioni, come le collocazioni verbo + sostantivo. La scarsa disponibilità di corpora orali di discenti e la maggiore attenzione per le sequenze formulaiche più soggette a errori hanno portato i ricercatori a trascurare collocazioni come avverbio + aggettivo. L'intensificazione è una parte intricata dell'apprendimento delle lingue straniere (Lorenz, 1999) e merita ulteriore attenzione, soprattutto per quanto riguarda i dati parlati, che riflettono meglio il linguaggio dei discenti (Myles, 2015). Il presente lavoro indaga le collocazioni di avverbi + aggettivi in un corpus parlato di recente compilazione di studenti italiani avanzati di inglese L2. La tesi adotta un approccio di Analisi Interlinguistica Contrastiva (Granger, 1998) per verificare se: a) ci sono differenze tra la produzione di collocazioni degli studenti italiani di inglese rispetto ai coetanei madrelingua; b) ci sono differenze tra le collocazioni prodotti dagli studenti italiani e quelle dei madrelingua in termini di modelli sintattici e significato lessicale; c) la congruenza della L1 ha un effetto di trasferimento sulla produzione da parte dei discenti di collocazioni poco frequenti e/o non attestate. Per rispondere alle tre domande di ricerca, sono state condotte analisi quantitative e qualitative sull'Italian Spoken Learner Corpus (ISLC) e sul corpus gemello di LINDSEI, LOCNEC. LOCNEC è stato utilizzato come corpus di riferimento di madrelingua per il suo alto livello di comparabilità con ISLC. Per le analisi quantitative, è stato seguito l'approccio di Durrant e Schmitt (2009) per il calcolo dei punteggi delle misure di associazione delle collocazioni (t-score e MI) sulla base del corpus di riferimento BNC e le collocazioni sono state poi divise in tre categorie in base al loro punteggio: collocazioni (t-score e MI maggiore o uguale a 2 e 3 rispettivamente), collocazioni infrequenti/non attestate (t-score e MI non disponibili a causa dell'infrequenza), collocazioni in area grigia (t-score e MI inferiore a 2 e 3 rispettivamente). I test T-test e Wilcoxon rank sum test sono stati utilizzati sulle collocazioni estratte da ISLC e LOCNEC e sono state calcolate le dimensioni degli effetti. Inoltre, i test sono stati impiegati per valutare i valori medi individuali di t-score e MI degli studenti e dei madrelingua. Per quanto riguarda le analisi qualitative, è stato impiegato uno schema a tre livelli per analizzare due serie di collocazioni: la prima serie comprende 11 collocazioni con t-score e MI maggiore uguale a 2 e 3 rispettivamente e una frequenza di 5 nell'ISLC; la seconda serie comprende 9 collocazioni infrequenti/non attestate con una frequenza maggiore o uguale a 2 nell'ISLC. Seguendo lo schema, i due set di collocazioni estratti sia dall'ISLC sia dal LOCNEC sono stati analizzati tenendo conto del loro background collocativo (etimologia, livello CEFR, congruenza L1), delle variabili del discente (sesso, esperienza di soggiorno all'estero, corso universitario, altre lingue), e delle variabili testuali (funzione attributiva vs predicativa dell'aggettivo, pronomi vs it-sentences, tempo verbale, affermativo vs negativo, connotazione positiva vs negativa). I risultati dei test statistici sono stati tutti significativi con effect size medio-grandi e, insieme alle analisi qualitative, hanno indicato che: gli studenti italiani di inglese producono un minor numero di collocazioni; un maggior numero di non-collocazioni; le loro combinazioni sono meno collocative di quelle dei madrelingua (ovvero, i loro punteggi di misura delle associazioni sono in media più bassi di quelli dei nativi); non ci sono differenze marcate in termini di modelli lessico-grammaticali tra le collocazioni degli studenti e quelle dei madrelingua, ma gli studenti tendono ad assegnare alle loro collocazioni funzioni più creative dal punto di vista pragmatico; non è stata trovata alcuna prova di trasferimento L1 (negativo) in relazione alla produzione da parte dei discenti di collocazioni infrequenti/non attestate, sostenendo così ulteriormente la conclusione precedente. I risultati corroborano ulteriormente la letteratura sulle collocazioni prodotte dai discenti e aggiungono un altro tassello al puzzle della lingua parlata: il ritardo collocazionale, cioè lo sviluppo più lento delle prestazioni di produzione di collocazioni, può essere trovato anche nei dati parlati e i discenti sembrano anche produrre meno collocazioni identificate da punteggio t-score. Questo ha due importanti, anche se semplici, implicazioni: che gli studenti dovrebbero probabilmente essere esposti a più input di lingua parlata, e che le teorie di acquisizione della lingua seconda potrebbero utilmente rivedere i processi di acquisizione fraseologica degli studenti nel contesto EFL. Un'altra scoperta è relativa ai modelli lessico-grammaticali delle collocazioni degli studenti non erano marcatamente diversi da quelli dei madrelingua, ma erano meno vari e mostravano una creatività pragmatica. Questo potrebbe informare gli studiosi sui potenziali processi di fossilizzazione (Selinker, 1972) nella fraseologia e/o sulle strategie di semplificazione o di evitamento (Farghal & Obiedat, 1995). Infine, anche se gli studi tradizionali hanno trovato che la congruenza L1 gioca un ruolo chiave nella produzione di collocazioni (cfr. Bahns, 1993; Granger, 1998b; Nesselhauf, 2005; Wang, 2016), nessuna prova di congruenza L1 è stata trovata per quanto riguarda i dati parlati, il che è un'interessante controprova. Nel complesso, questa tesi ha sottolineato che la produzione di collocazioni, sia quantitativamente sia pragmaticamente, è in ritardo rispetto alla competenza collocazionale e, sebbene questa linea possa essere molto sottile e non significativa nei testi scritti, il divario si allarga nella lingua parlata.In the last 70 years, there has been an increase in English studies on collocations (Firth 1957; Hoey, 2005; Moon, 1998; Sinclair 1991; 2004; Stubbs, 1996; 2001) and research which have documented that phraseology is pervasive to language (Altenberg, 1998; Biber et al., 1999; Cowie, 1991; 1992; Howarth; 1998). This also indicates that a good command of collocations is needed if learners aim to achieve native-like fluency in the L2. Indeed, research on learner production of formulaic language has shown that collocations are essential in the acquisition of second language (Cowie, 1998; Pawley & Syder, 1983; Peters, 1983) and are a key component for the development of fluency (Ellis, 2002; 2003; Ellis et al., 2015; Howarth, 1998). Despite the surge in studies on collocations, the majority of scholars have focused on written data and on a restricted set of combinations, such as verb + noun collocations. The poor availability of spoken learner corpora and the more error-prone formulaic sequences have led researchers to neglect collocations such as adverb + adjective. Intensification is an intricate part of foreign language learning (Lorenz, 1999) and deserves further attention, especially as regards spoken data, which is a better reflection of learner language (Myles, 2015). The present work investigates adverb + adjective collocations in a newly compiled spoken learner corpus of advanced Italian learners of English L2. The thesis adopts a Contrastive Interlanguage Analysis (Granger, 1998) approach to verify whether: a) there are any differences between the collocation production of Italian learners of English compared to native-speaker peers; b) there are any differences between the Italian learners’ collocations and the native speakers’ in terms of syntactic patterns and lexical meaning; c) L1 congruency has a transfer effect on the learner production of infrequent and/or unattested collocations. In order to address the three overarching research questions, quantitative and qualitative analyses were carried out on the Italian Spoken Learner Corpus (ISLC) and the sister corpus of LINDSEI, LOCNEC. LOCNEC was used as the native-speaker reference corpus for its high level of comparability to ISLC. For the quantitative analyses, Durrant and Schmitt’s (2009) approach was followed for the calculation of the collocation’s association measure scores (t-score and MI) based on the large reference corpus BNC and the collocations were then divided into three categories based on their score: collocations (t-score and MI equal or greater than 2 and 3 respectively), infrequent/unattested collocations (t-score and MI scores unavailable due to infrequency), grey area collocations (t-score and MI lower than 2 and 3 respectively). T-tests and Wilcoxon rank sum tests were computed on the collocations extracted from ISLC and LOCNEC and effect sizes were calculated. In addition, the tests were employed to assess the average individual t-score and MI values of learners and native speakers. As regards the qualitative analyses, a three-fold scheme was employed to analyse two sets of collocations: the first set comprises 11 collocations with t-score and MI equal or greater than 2 and 3 respectively and a frequency of equal or greater than 5 in the ISLC; the second set includes 9 infrequent/unattested collocations with a frequency equal or greater than 2 in ISLC. Following the scheme, the two sets of collocations extracted from both ISLC and LOCNEC were analysed by taking into account their collocational background (etymology, CEFR level, L1 congruence), the learner variables (gender, stay-abroad experience, university course, other languages), and the text variables (attributive vs predicative function of the adjective, pronouns vs it-sentences, tense, affirmative vs negative, positive vs negative connotation). The results of the statistical tests were all significant with medium to large effect sizes and, together with the qualitative analyses, indicated that: Italian learners of English produce a fewer number of collocations; a higher number of non-collocations; their combinations are less collocational than native speakers’ (i.e., their association measure scores as on average lower than the natives’); there are no marked differences in terms of lexico-grammatical patterns between the learners’ collocations and the native speakers’, but the learners tend to assign more pragmatically creative functions to their collocations; no evidence of L1 (negative) transfer was found in relation to the learners’ production of infrequent/unattested collocations, thus further supporting the previous finding. The findings further corroborate the literature on learners’ collocations and add another piece to the puzzle of spoken language: collocational lag, that is the slower development of collocation performance, can also be found in spoken data and learners also seem to produce fewer t-score collocations. This has two important, though simple, implications: that learners should probably be exposed to more spoken language input, and that second language acquisition theories might usefully review phraseological acquisition processes of EFL learners. Another finding is that the lexico-grammatical patterns of learners’ collocations were not markedly different from native speakers’, but they were less varied and displayed pragmatic creativity. This could inform scholars about potential fossilisation processes (Selinker, 1972) in phraseology and/or simplification or avoidance strategies (Farghal & Obiedat, 1995). Lastly, although mainstream studies have found that L1 congruency plays a role in the production of collocations (cf. Bahns, 1993; Granger, 1998b; Nesselhauf, 2005; Wang, 2016), no evidence of L1 congruency was found as regards spoken data, which is an interesting counter-finding. Overall, this thesis has underlined that collocation production, both quantitatively and pragmatically, lags behind collocation competence and, although this line may be very thin and not significant in written texts, the gap widens in spoken language

Dietary Management in IBS Patients

Irritable bowel syndrome (IBS) is a chronic, relapsing functional disorder of the gastrointestinal tract characterized by abdominal pain, bloating, and changes in bowel habits lacking a known structural or anatomic explanation. According to the Rome IV criteria, IBS consists of a set of altered bowel habits over a period of time and includes abdominal pain and discomfort. The pathogenesis of IBS is not completely understood, although it has been noted that various mechanisms are involved determining the onset of symptoms. The risk factors include antibiotics, enteric infection, food intolerance, altered pain perception, altered brain-gut interaction, dysbiosis, increased intestinal permeability, visceral hypersensitivity, and increased activation of the gut mucosal immune system. There has been interest regarding the possible role of food in IBS. Diet is crucial for managing IBS; it plays an important role both in the genesis and in the improvement of symptoms. The aim of the study was to summarize the evidence from the literature, which explains those causes tending to promoting IBS symptoms, such as food content short-chain carbohydrates and the presence of food allergy or food intolerance

Unveiling crisis in globalised higher education: Artificial intelligence insights from doctoral research in EThOS

This paper seeks to illuminate new perspectives on the concept of crisis in globalised higher education (HE) by focusing on knowledge generated by doctoral research. Doctoral research is a significant part of research and knowledge building in HE, particularly in science, and doctoral students contribute to the research capacity and knowledge building of institutions. This source of knowledge offers alternative perspectives on crisis in HE, providing a rich source of research which is often under‐consulted. Using the British Library's digital repository EThOS, a collection of around 637,000 doctoral studies carried out in British universities, the research harnesses Generative Artificial Intelligence approaches in order to analyse the ways in which crisis is defined and constructed in doctoral research since 2000. Through a pilot study using a prototype of a new AI tool, the paper offers both conceptual and methodological insights into constructions of crisis in this under‐used field of research

Electrostatic instabilities and turbulence in a toroidal magnetized plasma

This Thesis aims at characterizing the linear properties of electrostatic drift instabilities arising in a toroidal plasma and the mechanisms leading to their development into turbulence. The experiments are performed on the TORoidal Plasma EXperiment (TORPEX) at CRPP-EPFL, Lausanne. The first part of the Thesis focuses on the identification of the nature of the instabilities observed in TORPEX, using a set of electrostatic probes, designed and built for this purpose. The global features of fluctuations, analyzed for different values of control parameters such as the magnetic field, the neutral gas pressure and the injected microwave power, are qualitatively similar in different experimental scenarios. The maximum of fluctuations is observed on the low field side, where the pressure gradient and the gradient of the magnetic field are co-linear, indicating that the curvature of the magnetic field lines has an important role in the destabilization of the waves. The power spectrum is dominated by electrostatic fluctuations with frequencies much lower than the ion cyclotron frequency. Taking advantage of the extended diagnostics coverage, the spectral properties of fluctuations are measured over the whole poloidal cross-section. Both drift and interchange instabilities develop and propagate on TORPEX, with the stability of both being affected by the curvature of the magnetic field. It is shown that modes of different nature are driven at separate locations over the plasma cross-section and that the wavenumber and frequency spectra, narrow at the location where the instabilities are generated, broaden during convection, suggesting an increase in the degree of turbulence. The transition from coherent to turbulent spectral features and the role of nonlinear coupling between modes in the development of turbulence are treated in the second part of this work. It is found that nonlinear mode-mode coupling is responsible for the redistribution of spectral energy from the dominant instabilities to other spectral components and that this mechanism is independent of the nature of the instabilities. Nonlinear interactions between the mode and its nonlinearly generated harmonics are responsible for the filling of the spectral regions between harmonics. Later in the development along the convection path, the unstable mode transfers energy to spectral components with significantly larger frequencies. This transfer of energy can be interpreted in the investigated plasma scenarios as a forward cascade in wavenumbers, with transfer of energy from large to small scales

Co-localization of PTEN and E-cadherin in canine mammary hyperplasias and benign and malignant mammary tumours

Fifty-four canine mammary lesions (15 hyperplasias, 7 adenomas and 32 carcinomas) were submitted to immunohistochemical analysis for the evaluation of PTEN and E-cadherin co-expression. Subjects bearing mammary carcinomas were also submitted to a 2-year follow-up study to compare immunohistochemical results with overall survival All the hyperplastic samples stained positive for both markers, 100% of adenomas were positive for PTEN and 86% for E-cadherin, and 69% and 34% of carcinomas were positive for PTEN and E-cadherin, respectively. Statistical analysis showed a positive correlation between these two proteins both considering all (p <0.01) or malignant tumours (p <0.05). The female dogs bearing tumours positively-stained for both markers had a longer overall survival (p <0.05) and absence of lymphatics invasion (p <0.05). Simultaneous double immunofluorescence confirmed the co-localization of the two proteins in neoplastic cells. Results reported in this study confirm the tumor suppressor effect of these two molecules

COX-2, mPGES-1 and EP2 receptor immunohistochemical expression in canine and feline malignant mammary tumours

Prostaglandin (PG) signalling is involved in human and animal cancer development. PG E2 (PGE2) tumour-promoting activity has been confirmed and its production is controlled by Cyclooxygenase-2 (COX-2) and microsomal PGE synthase-1 (mPGES-1). Evidence suggests that mPGES-1 and COX-2 contribute to carcinogenesis through the EP2 receptor. The aim of our study was to detect by immunohistochemistry COX-2, mPGES-1 and EP2 receptor expression in canine (n=46) and feline (n=50) mammary tumours and in mammary non-neoplastic tissues. COX-2 positivity was observed in 83% canine and 81% feline mammary carcinomas, mPGES-1 in 75% canine and 66% feline mammary carcinomas and the EP2 receptor expression was observed in 89% canine and 54% feline carcinomas. The frequency of COX-2, EP2 receptor and mPGES-1 expression was significantly higher in carcinomas than in non-neoplastic tissues and adenomas. COX-2, mPGES-1 and EP2 receptor expression was strongly associated. These findings support a role of the COX-2/PGE2 pathway in the pathogenesis of these tumours