POWER EXHAUST DATA ANALYSIS AND MODELING OF ADVANCED DIVERTOR CONFIGURATIONS

The possibility to exploit fusion energy in a reliable, safe and available way is one of the greatest challenges in the worldwide research. Very hot magnetically confined plasma are required to achieve high rates of fusion reactions. However, these conditions are not compatible with the material facing the plasma. In order to protect the wall, a hot core confined region is created while most of the power and particles are ultimately exhausted in a properly design component of the reactor, the so-called divertor. The Ph.D. activity presented in this thesis is carried out in the framework of EUROfusion program for the realization of a Demonstration power plant (DEMO) by the years 2050 . One of the most critical aspects has been recognized in the exhaust of huge amount of power which can severely damage the plasma facing component (PFC). Therefore, the analysis of the plasma conditions in the divertor region is essential to asses the reliability and the feasibility of a fusion reactor machine. In order to mitigate the power exhaust issue the fusion community is currently investigating several possible solutions as the use of alternative magnetic divertor configurations (AC) or the use of liquid metal as PFC. This thesis focuses on the study of the Scrape off Layer (SOL), the region where the particles coming out of the core are diverted towards the target plates. The modelling is performed by means of 2D edge codes on future and existing fusion reactors. The first point in the analysis is the assessment of the edge plasma conditions in DEMO by considering a set of simplifying assumptions and taking into account a possible set of reference parameters. A scoping study is performed to evaluate the behaviour of the SOL plasma by varying the density and the transport coefficients. The numerical simulations are performed by means of the EDGE2D-EIRENE code. The results of the calculations predict divertor conditions totally unacceptable from an operational point of view. Most importantly, since the most used and validated code available in the fusion community are not able to deal with ACs, we perform a benchmark between EDGE2D-EIRENE and TECXY. The latter is a simple and fast code able to treat ACs. Despite the differences in the physical model adopted by the two numerical tools, the results shows a good match, especially in terms of power loads on the target plates and general trends of global quantities. On the other hand, discrepancies are observed in the electron density and temperature profiles on the outer divertor primarily due to the different numerical models adopted for the neutral particles description. As a second step, we perform the analysis of an AC by comparing a conventional Single Null (SN) and a Quasi snowflake (QSF, characterized by a transition from Snowflake to X-Divertor configurations) magnetic configurations of DTT (Divertor Test Tokamak). The modelling is performed by means of EDE2D-EIRENE. The scoping study obtained by varying the upstream density investigates three different aspects: the effect on the attainment of the detachment, the effect on the power loads and the effect on the neutral particles behaviour. The simulations show that the QSF configuration is more prone to reach detached divertor conditions than the SN configurations. Furthermore, while in SN unacceptable power loads are foreseen onto the outer target plates, in case of QSF manageable values of the power peaks are obtained. This difference is primarily due to geometrical factors, especially the main driver is recognized in the flaring of the flux surfaces in the divertor region. By analysing the neutral particles behaviour, we see that a better confinement is achieved in QSF than in SN since the ionization front is not able to move towards the X-point. A preliminary analysis of liquid lithium divertor is also discussed. Since we simulate regimes dominated by the sputtering, minor differences are observed by comparing the liquid lithium divertor and the standard Tungsten one. The last point of the research activity concerns the use of a different 2D edge code, i.e. SOLEDGE2D-EIRENE. Thanks to the high flexibility, this code is able to treat ACs. We discuss the preliminary results of a validation phase carried out by comparing the numerical results with the experimental one. While the upstream profiles are fairly reproduced by varying the diffusion coefficients, the target quantities shows mismatches in terms of electron density and temperature whereas the power profile is partially recovered. The results are then compared in terms of radiation distribution. The code is able to reproduce the 2D distribution in the high field side, even though discrepancies on the inner divertor baffle are observed. Finally, we show that improvements can be obtained by suitably defining the recycling coefficient

Negative regulation of beta enolase gene transcription in embryonic muscle is dependent upon a zinc finger factor that binds to the G-rich box within the muscle-specific enhancer.

We have previously identified a muscle-specific enhancer within the first intron of the human beta enolase gene. Present in this enhancer are an A/T-rich box that binds MEF-2 protein(s) and a G-rich box (AGTGGGGGAGGGGGCTGCG) that interacts with ubiquitously expressed factors. Both elements are required for tissue-specific expression of the gene in skeletal muscle cells. Here, we report the identification and characterization of a Kruppel-like zinc finger protein, termed beta enolase repressor factor 1, that binds in a sequence-specific manner to the G-rich box and functions as a repressor of the beta enolase gene transcription in transient transfection assays. Using fusion polypeptides of beta enolase repressor factor 1 and the yeast GAL4 DNA-binding domain, we have identified an amino-terminal region responsible for the transcriptional repression activity, whereas a carboxyl-terminal region was shown to contain a potential transcriptional activation domain. The expression of this protein decreases in developing skeletal muscles, correlating with lack of binding activity in nuclear extract from adult skeletal tissue, in which novel binding activities have been detected. These results suggest that in addition to the identified factor, which functionally acts as a negative regulator and is enriched in embryonic muscle, the G-rich box binds other factors, presumably exerting a positive control on transcription. The interplay between factors that repress or activate transcription may constitute a developmentally regulated mechanism that modulates beta enolase gene expression in skeletal muscle

Micro-CT Evaluation of Gutta-Percha Removal by Two Retreatment Systems

Introduction: The aim of the present ex vivo research was to compare the remaining filling material and the volumes of dentine removed after retreatment of curved canals with two rotary systems naming ProTaper Universal Retreatment and Mani NRT-GPR using micro-computed tomography (micro-CT). Material and Methods: Forty mandibular molars containing two completely separated canals, with curvature angle of 25-35° and a curvature radius <10 mm were prepared to the Mtwo instrument 35/0.04 and filled with warm gutta-percha and AH-Plus sealer. The teeth were randomly divided into 2 groups (n=20), according to the retreatment system evaluated: ProTaper Universal Retreatment (PR group) or Mani NRT-GPR (MR group). Retreatment was considered complete when the working length was reached and when smooth dentinal walls were observed, with no evidence of filling material adhered to instruments or in the irrigating solution. Preoperative and postoperative micro-CT images were obtained with an isotropic voxel size of 11.88 µm to observe the volume of residual filling material in the canals and dentine removed after retreatment. Statistical analysis was performed by Student’s t-test (P<0.05). Results: The mean percentage of remaining filling material was 12.96% for PR group and 24.26% for MR group (P=0.0056). The percentage of dentin removal was greater in the PR group (5.02%) than MR group (1.36%) (P=0.0028). Both systems failed to completely remove the filling material from the canals. Conclusion: ProTaper Universal Retreatment system was more effective than Mani NRT-GPR system regarding removal of root filling material and also removed significantly more dentine after retreatment of curved mesial root canals of mandibular molars.Keywords: Dental Instruments; Endodontics; Gutta-Percha; Endodontic Retreatment

Insights from cardiopulmonary exercise testing in pediatric patients with hypertrophic cardiomyopathy

The usefulness of cardiopulmonary exercise test (CPET) in adult hypertrophic cardiomyopathy (HCM) patients is well-known, whereas its role in pediatric HCM patients has not yet been explored. The present study investigates possible insights from a CPET assessment in a cohort of pediatric HCM outpatients in terms of functional and prognostic assessment. Sixty consecutive pediatric HCM outpatients aged <18 years old were enrolled, each of them undergoing a full clinical assessment including a CPET; a group of 60 healthy subjects served as controls. A unique composite end-point of heart failure (HF) related and sudden cardiac death (SCD) or SCD-equivalent events was also explored. During a median follow-up of 53 months (25th–75th: 13–84 months), a total of 13 HF- and 7 SCD-related first events were collected. Compared to controls, HCM patients showed an impaired functional capacity with most of them showing peak oxygen uptake (pVO2) values of <80% of the predicted, clearly discrepant with functional New York Heart Association class assessment. The composite end-point occurred more frequently in patients with the worst CPETs’ profiles. At the univariate analysis, pVO2% was the variable with the strongest association with adverse events at follow-up (C-index = 0.72, p = 0.025) and a cut-off value equal to 60% was the most accurate in identifying those patients at the highest risk. In a pediatric HCM subset, the CPET assessment allows a true functional capacity estimation and it might be helpful in identifying early those patients at high risk of events.publishedVersio

A moda no MASP de Pietro Maria Bardi (1947-1987)

O objetivo deste artigo é evidenciar a centralidade das ações ligadas à moda e à formação da Seção de Costumes do MASP no projeto de museu e na concepção de arte de Pietro Maria Bardi no período 1947-1987, e como tais ações teriam sido relevantes para a instituição de uma visualidade e uma história para a moda nacional. Demonstra-se como a trajetória de P. M. Bardi na Itália, ou seja, sua atuação como galerista e comerciante de artes, jornalista, bem como seu contato com a ideologia e as ações do Regime Fascista no campo das artes e da moda, influenciou diretamente suas ações em relação ao design de moda. Essas ideias e experiências foram fundamentais para direcionar sua atuação no MASP e, em especial suas iniciativas na área do design. Nota-se ainda como a atuação de Bardi no campo do design de moda foi também influenciada pelas ideias propagadas pela Bauhaus e Le Corbusier, assim como por seu olhar estrangeiro, que acaba por levá-lo a recuperar, nas referentes iniciativas, as tradições e a cultura brasileiras, gerando uma produção que dialoga com o modernismo brasileiro, uma vez que usa a experiência internacional para valorizar o nacional

3 years of liraglutide versus placebo for type 2 diabetes risk reduction and weight management in individuals with prediabetes: a randomised, double-blind trial

Background: Liraglutide 3·0 mg was shown to reduce bodyweight and improve glucose metabolism after the 56-week period of this trial, one of four trials in the SCALE programme. In the 3-year assessment of the SCALE Obesity and Prediabetes trial we aimed to evaluate the proportion of individuals with prediabetes who were diagnosed with type 2 diabetes. Methods: In this randomised, double-blind, placebo-controlled trial, adults with prediabetes and a body-mass index of at least 30 kg/m2, or at least 27 kg/m2 with comorbidities, were randomised 2:1, using a telephone or web-based system, to once-daily subcutaneous liraglutide 3·0 mg or matched placebo, as an adjunct to a reduced-calorie diet and increased physical activity. Time to diabetes onset by 160 weeks was the primary outcome, evaluated in all randomised treated individuals with at least one post-baseline assessment. The trial was conducted at 191 clinical research sites in 27 countries and is registered with ClinicalTrials.gov, number NCT01272219. Findings: The study ran between June 1, 2011, and March 2, 2015. We randomly assigned 2254 patients to receive liraglutide (n=1505) or placebo (n=749). 1128 (50%) participants completed the study up to week 160, after withdrawal of 714 (47%) participants in the liraglutide group and 412 (55%) participants in the placebo group. By week 160, 26 (2%) of 1472 individuals in the liraglutide group versus 46 (6%) of 738 in the placebo group were diagnosed with diabetes while on treatment. The mean time from randomisation to diagnosis was 99 (SD 47) weeks for the 26 individuals in the liraglutide group versus 87 (47) weeks for the 46 individuals in the placebo group. Taking the different diagnosis frequencies between the treatment groups into account, the time to onset of diabetes over 160 weeks among all randomised individuals was 2·7 times longer with liraglutide than with placebo (95% CI 1·9 to 3·9, p&lt;0·0001), corresponding with a hazard ratio of 0·21 (95% CI 0·13–0·34). Liraglutide induced greater weight loss than placebo at week 160 (–6·1 [SD 7·3] vs −1·9% [6·3]; estimated treatment difference −4·3%, 95% CI −4·9 to −3·7, p&lt;0·0001). Serious adverse events were reported by 227 (15%) of 1501 randomised treated individuals in the liraglutide group versus 96 (13%) of 747 individuals in the placebo group. Interpretation: In this trial, we provide results for 3 years of treatment, with the limitation that withdrawn individuals were not followed up after discontinuation. Liraglutide 3·0 mg might provide health benefits in terms of reduced risk of diabetes in individuals with obesity and prediabetes. Funding: Novo Nordisk, Denmark

POWER EXHAUST DATA ANALYSIS AND MODELING OF ADVANCED DIVERTOR CONFIGURATIONS

The possibility to exploit fusion energy in a reliable, safe and available way is one of the greatest challenges in the worldwide research. Very hot magnetically confined plasma are required to achieve high rates of fusion reactions. However, these conditions are not compatible with the material facing the plasma. In order to protect the wall, a hot core confined region is created while most of the power and particles are ultimately exhausted in a properly design component of the reactor, the so-called divertor. The Ph.D. activity presented in this thesis is carried out in the framework of EUROfusion program for the realization of a Demonstration power plant (DEMO) by the years 2050 . One of the most critical aspects has been recognized in the exhaust of huge amount of power which can severely damage the plasma facing component (PFC). Therefore, the analysis of the plasma conditions in the divertor region is essential to asses the reliability and the feasibility of a fusion reactor machine. In order to mitigate the power exhaust issue the fusion community is currently investigating several possible solutions as the use of alternative magnetic divertor configurations (AC) or the use of liquid metal as PFC. This thesis focuses on the study of the Scrape off Layer (SOL), the region where the particles coming out of the core are diverted towards the target plates. The modelling is performed by means of 2D edge codes on future and existing fusion reactors. The first point in the analysis is the assessment of the edge plasma conditions in DEMO by considering a set of simplifying assumptions and taking into account a possible set of reference parameters. A scoping study is performed to evaluate the behaviour of the SOL plasma by varying the density and the transport coefficients. The numerical simulations are performed by means of the EDGE2D-EIRENE code. The results of the calculations predict divertor conditions totally unacceptable from an operational point of view. Most importantly, since the most used and validated code available in the fusion community are not able to deal with ACs, we perform a benchmark between EDGE2D-EIRENE and TECXY. The latter is a simple and fast code able to treat ACs. Despite the differences in the physical model adopted by the two numerical tools, the results shows a good match, especially in terms of power loads on the target plates and general trends of global quantities. On the other hand, discrepancies are observed in the electron density and temperature profiles on the outer divertor primarily due to the different numerical models adopted for the neutral particles description. As a second step, we perform the analysis of an AC by comparing a conventional Single Null (SN) and a Quasi snowflake (QSF, characterized by a transition from Snowflake to X-Divertor configurations) magnetic configurations of DTT (Divertor Test Tokamak). The modelling is performed by means of EDE2D-EIRENE. The scoping study obtained by varying the upstream density investigates three different aspects: the effect on the attainment of the detachment, the effect on the power loads and the effect on the neutral particles behaviour. The simulations show that the QSF configuration is more prone to reach detached divertor conditions than the SN configurations. Furthermore, while in SN unacceptable power loads are foreseen onto the outer target plates, in case of QSF manageable values of the power peaks are obtained. This difference is primarily due to geometrical factors, especially the main driver is recognized in the flaring of the flux surfaces in the divertor region. By analysing the neutral particles behaviour, we see that a better confinement is achieved in QSF than in SN since the ionization front is not able to move towards the X-point. A preliminary analysis of liquid lithium divertor is also discussed. Since we simulate regimes dominated by the sputtering, minor differences are observed by comparing the liquid lithium divertor and the standard Tungsten one. The last point of the research activity concerns the use of a different 2D edge code, i.e. SOLEDGE2D-EIRENE. Thanks to the high flexibility, this code is able to treat ACs. We discuss the preliminary results of a validation phase carried out by comparing the numerical results with the experimental one. While the upstream profiles are fairly reproduced by varying the diffusion coefficients, the target quantities shows mismatches in terms of electron density and temperature whereas the power profile is partially recovered. The results are then compared in terms of radiation distribution. The code is able to reproduce the 2D distribution in the high field side, even though discrepancies on the inner divertor baffle are observed. Finally, we show that improvements can be obtained by suitably defining the recycling coefficient.La possibilitá di poter sfruttare l’energia da fusione in modo affidabile, sicuro and con alta disponibilitá é una delle piú grandi sfide della ricerca mondiale. Plasmi ad altissima temperatura confinati magneticamente sono necessari per raggiungere alti tassi di reazioni di fusione. Tuttavia queste condizioni non sono compatibili con i materiali affacciati sul plasma. Al fine di proteggere la parete, viene creato un regione molto calda confinata mentre la maggior parte della potenza e delle particelle sono essenzialmente smaltite in uno specifico componente del reattore, il cosiddetto ’divertore’. L’attivitá di ricerca del dottorato presentato in questa tesi é stata fatta all’interno del programma EUROfusion per la realizzazione di un reattore dimostrativo (DEMO) entro il 2050. Uno degli aspetti piú critici é stato individuato nello smaltimento di alte potenze che possono danneggiare irreparabilmente i componenti affacciati al plasma (PFC). Quindi, l’analisi delle condizioni di plasma nella regione del divertore é essenziale per valutare l’affidabilitá e la fattibilitá dei reattori a fusione. Al fine di mitigare il problema dello smaltimento della potenza la comunitá fusionistica sta attualmente studiando diverse soluzioni possibili come l’uso di configurazioni magnetiche alternative nel divertore (AC) o l’uso di metalli liquidi come PFC. Questa tesi si concentra sullo studio dello Scrape off Layer (SOL), la regione dove le particelle che escono dal nucleo caldo sono dirottate verso i piatti del divertore. La modellazione numerica viene effettuata con codici di bordo bidimensionali su macchine future ed esistenti. Il primo punto nell’analisi consiste nella valutazione delle condizioni del plasma di bordo in DEMO considerando alcune ipotesi semplificative e un insieme di parametri di riferimento. Uno studio esplorativo viene fatto per valutare il comportamento del plasma nel SOL variando la densitá e i coefficienti di trasporto. Le simulazioni numeriche sono state fatte con il codice EDGE2D-EIRENE. I risultati predicono condizioni nel divertore totalmente inaccetabili dal punto di vista operazionale. Abbiamo soprattutto effettuato un benchmark tra EDGE2D-EIRENE e TECXY dato che i codici piú utilizzati e verificati attualmente disponibili nella comunitá fusionistica non sono in grado di trattare le AC. TECXY é un codice semplice e veloce in grado di gestire le AC. Nonostante le differenze nei modelli fisici utilizzati nei due codici, i risultati mostrano un buon accordo, in particolare in termini di carichi termici sui piatti del divertore e trend generali delle quantitá globali. D’altro canto discrepanze sono osservate nei profili della temperature e densitá elettronica sul divertore esterno principalmente dovute ai diversi modelli numerici adottati per la descrizione delle particelle neutre. Il secondo punto nell’analisi riguarda le AC fatta comparando una configurazione magnetica a singolo nullo (SN) convenzionale con un quasi Snowflake (QSF, caratterizzato da una transizione da una configurazione Snowflake ad una X-divertor) del reattore DTT (Divertor Test Tokamak). La modellizzazione é fatta con EDGE2DEIRENE. Lo studio preliminare effettuato variando la densitá a monte si propone di indagare tre aspetti principali: l’effetto sul raggiungimento del detachment, l’effetto sui carichi termici e l’effetto sul comportamento dei neutri. Le simulazioni mostrano che la configurazione QSF é piú incline a raggiungere il detachment rispetto al caso SN. Inoltre, mentre nel caso SN sono predetti carichi termici inaccetabili sui piatti esterni, in QSF sono ottenuti valori gestibili di picchi di potenza. Questa differenza risiede principalmente in fattori geometrici ed in particolare il fattore primario é riconducibile all’allargamento delle superfici di flusso nella regione del divertore. Analizzando il comportamento dei neutri si osserva un miglior confinamento in QSF che in SN dato che il fronte di ionizzazione non riesce a risalire verso il punto ad X. Un’analisi preliminare di un divertore a litio liquido é anche discussa. Leggere differenze sono osservate confrontando il divertore a litio liquido e quello convenzionale in tungsteno in quanto vengono simulati regimi dominati dallo sputtering. L’ultimo punto nell’attivitá di ricerca riguarda l’utilizzo di un diverso codice di bordo, SOLEDGE2D-EIRENE. Grazie all’alta flessibilitá, questo codice é in grado di trattare le AC. Vengono discussi i risultati preliminari della fase di convalida effettuata confrontando i risultati numerici con quelli sperimentali. Mentre i profili a monte sono discretamente riprodotti variando i coefficienti di diffusione, le quantitá a valle mostrano discrepanze in termini di densitá e temperature elettroniche. D’altro canto il profilo di potenza é parzialmente riprodotto. I risultati sono successivamente comparati in termini di distribuzione della radiazione. Il codice riesce a riprodurre la distribuzione 2D nella parte ad alto campo anche se differenze sul baffle interno sono presenti. Infine mostriamo che miglioramenti possono essere ottenuti definendo in modo adatto il coefficiente di riciclo

Polyhydroxylated Nanosized Graphite as Multifunctional Building Block for Polyurethanes

Polyurethane nanocomposites were prepared with a nanosized high surface area graphite (HSAG) functionalized on its edges with hydroxyl groups as a building block. Edge functionalization of HSAG was obtained through reaction with KOH. The addition of OH groups was demonstrated by means of infrared (FTIR) and thermogravimetric analysis (TGA), and the Boehm titration allowed estimation of a level of about 5.0 mmolOH/gHSAG. Results from wide-angle X-ray diffraction (WAXD) and Raman spectroscopy suggested that functionalization of the graphene layers occurred on the edges. The evaluation of the Hansen solubility parameters of G-OH revealed a substantial increase of &delta;P and &delta;H parameters with respect to HSAG. In line with these findings, homogeneous and stable dispersions of G-OH in a polyol were obtained. PU were prepared by mixing a dispersion of G-OH in cis-1,4-butenediol with hexamethylene diisocyanate. A model reaction between catechol, 1,4-butanediol, and hexamethylene diisocyanate demonstrated the reactivity of hydroxylated aromatic rings with isocyanate groups. PU-based G-OH, characterized with WAXD and differential scanning calorimetry (DSC), revealed lower Tg, higher Tc, Tm, and crystallinity than PU without G-OH. These results could be due to the higher flexibility of the polymer chains, likely a consequence of the dilution of the urethane bonds by the carbon substrate. Hence, G-OH allowed the preparation of PU with a larger temperature range between Tg and Tm, with potential positive impact on material applications. The model reaction between butylisocyanate and 1-butanol revealed that HSAG and G-OH promote efficient formation of the urethane bond, even in the absence of a catalyst. The effect of high surface area carbon on the nucleophilic oxygen attack to the isocyanate group can be hypothesized. The results here reported lead us to comment that a reactive nanosized sp2 carbon allotrope, such as G-OH, can be used as a multifunctional building block of PU. Indeed, G-OH is a comonomer of PU, a promoter of the polymerization reaction, and can definitely act as reinforcing filler by tuning its amount in the final nanocomposite leading to highly versatile materials. The larger temperature range between Tg and Tm, together with the presence of G-OH acting as a reinforcing agent, could allow the production of piezoresistive sensing, shape-memory PU with good mechanical features

Non-ergodic probabilistic seismic hazard methodology using physics-based ground motion prediction: the case of L'Aquila, Italy

A non-ergodic probabilistic seismic hazard analysis (PSHA) utilizing the physics-based ground motion prediction was proposed in this study to minimize the increasing uncertainties in the use of empirical equations. The City of L’Aquila in Italy was used for illustrative purposes due to the availability of data and the historical seismicity of the site. A total of 28 seismic sources were identified in this study located within a 100 km radius from the city. Fault properties such as geometry and location were obtained from the literature, while the fault occurrence rates were obtained using the FiSH Code. A modified time-weakening friction law was proposed to model the seismic energy released by an earthquake. Uncertainties in different rupture scenarios were characterized through the Guttenberg-Richter Relations and the Characteristic Brownian Time Passage. Uncertainties in distances were characterized through probability mass functions, which were used to calculate the ground motion exceedance probabilities. The 1D elastodynamic equation coupled with the Hooke’s law was used to predict the peak ground acceleration (PGA), a measure of the ground shaking level. A hazard curve, which is a plot of PGA and its recurrence, was constructed and compared with the results of the study of Valentini, et al., AGU 100: Advancing Earth and Space Science (2019). The method proposed in this study predicts a higher hazard rates for PGAs less than 0.70 g, which implies that the ground motion was overestimated for very far sources. In contrast, lower hazard curves were observed for PGAs greater than 0.70g which can be attributed to fewer seismic sources considered in this study