Ceramic characterization and factography of resin-ceramic adhesive interface after different ceramic surface treatments

Orientador: Alvaro Della Bona, Altair A. Del Bel CuryTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: Este estudo avaliou o efeito do tratamento de superfície na resistência adesiva à tração (s) entre resina e as cerâmicas IPS Empress®(E1) e VITAVM7®(V7) e o modo de falha nessa interface adesiva. A metodologia proposta teve por finalidade testar a hipótese de que a s entre resina e cerâmica é controlada pelo tratamento de superfície das cerâmicas. Foram confeccionados 10 blocos de uma cerâmica a base de leucita, (E1) e de uma cerâmica feldspática com duas fases vítreas (V7), que foram polidos até a granulação de 1 µm. Os blocos de cada cerâmica foram divididos aleatoriamente em dois grupos e tiveram suas superfícies tratadas como segue (n=5): Grupos E1HF e V7HF: aplicação de ácido hidrofluorídrico a 9,5% (HF - Ultradent) aplicado por 60 s; Grupos E1CS e V7CS: jateamento com partículas de alumina modificadas por sílica (CS ¿ Cojet System, 3M-Espe), aplicado por 15 s. As superfícies cerâmicas tratadas foram lavadas, secadas e o silano foi aplicado deixando-o evaporar. Aplicaram-se duas camadas finas de adesivo (Single Bond, 3M), seguido da aplicação de camadas de 2 mm de resina composta (Z250, 3M), que foram fotopolimerizadas durante 40 s cada uma. Os blocos cerâmica-adesivo-resina composta foram seccionados em dois eixos, x e y, obtendo-se corpos-de-prova em forma de barras (n=30), com área adesiva média de 1,04 mm2. Os corpos-de-prova foram armazenados em água destilada a 37°C por uma semana antes do teste de tração em uma máquina de ensaios universal com velocidade de carga de 1.0 mm.min-1, seguido da análise microscópica da superfície fraturada. A análise estatística foi realizada pela análise de variância, teste de Tukey (a=.01) e análise de Weibull. As médias e desvio padrão da s (MPa) foram: E1HF: 29,8±4,5(a); E1CS: 24,6±5,6(b); V7HF: 22,3±4,0(b); V7CS: 15,7±6,9(c). Os valores médios de s do Grupo E1HF foram significativamente maiores que os valores médios dos demais grupos (p=0,0001). As duas cerâmicas apresentaram valores médios de s significativamente maiores quando tratadas com HF do que com CS (p=0,0001). Todas as fraturas ocorreram dentro da zona adesiva. O módulo de Weibull (m) foi mais alto para o Grupo E1HF (7,66), e o Grupo V7CS mostrou o valor mais baixo de m (2,54). Os resultados confirmam a hipótese inicial de que a s da resina à cerâmica é controlada, primariamente, pelo tratamento de superfície do material cerâmicoAbstract: This study evaluated the effect of ceramic surface treatments on tensile bond strength (s) and the mode of failure of a resin bonded to two types of ceramics, testing the hypothesis that s of ceramics to resin is controlled by the ceramic surface treatment. Methods: Ten blocks of each the hot-pressed leucite-based ceramic (E1- IPS Empress) and the two-phase glassy feldspathic ceramic (V7-VITAVM7) were fabricated, polished through 1 µm alumina abrasive, and divided into two groups per ceramic (n=5): Groups E1HF and V7HF, 9.5% hydrofluoric acid (HF) was applied for 60 s; Groups E1CS e V7CS, silica coating (CS) using Cojet System (3M-Espe) for 15 s. The treated ceramic surfaces were washed and dried. Silane was applied and let to evaporate. An adhesive resin (Single Bond, 3M) followed by a resin composite (Z250, 3M) were applied on the ceramic treated surfaces and light cured. The composite-ceramic blocks were cut to produce bar-shaped specimens with a mean bonding area of 1.04 mm2 (n=30). Specimens were stored in 37°C distilled water for 1 week before tensile loading to failure in a universal testing machine with cross-head speed of 1.0 mm.min-1. Fracture surfaces were examined under scanning electron microscope (SEM). Results were statistically analyzed using one way ANOVA, Tukey¿s test and Weibull analyses. Results: Mean s and standard deviation (MPa) values were as follows: E1HF: 29.8±4.5(a); E1CS: 24.6±5.6(b); V7HF: 22.3±4.0(b); V7CS: 15.7±6.9(c). Mean s value of Group E1HF was statistically higher than the other Groups mean values (p=0.0001). HF treatment produced significantly higher mean s value than CS treatment, independent of the ceramic material (p=0.0001). All fractures occurred within the adhesion zone. E1HF showed the highest Weibull modulus (m) value (7.66) and V7CS exhibited the lowest m value (2.54). Conclusion: Results confirmed the testing hypothesis that s of ceramics to resin is controlled primarily by the ceramic surface treatmentDoutoradoProtese DentalDoutor em Clínica Odontológic

Risk factors and outcomes of oncohematologic patients admitted to Pediatric Intensive Care Unit: ONCOTIPNET, an Italian multicenter study

openNegli ultimi decenni sono stati fatti grandi progressi nell’ambito dell’oncologia pediatrica grazie a una conoscenza più profonda della biologia del cancro, che ha permesso di migliorare l’outcome dei pazienti attraverso protocolli di cura ottimizzati. Tuttavia i bambini con tumore possono sviluppare gravi complicanze legate alla malattia di base e ai trattamenti oncologici e possono necessitare di cure intensivistiche. L’obbiettivo primario del nostro studio è descrivere la popolazione di bambini affetti da tumore ricoverati nelle terapie intensive italiane considerando le variabili legate al periodo antecedente al ricovero in TIP e al ricovero in TIP stesso. L’obbiettivo secondario è identificare i fattori di rischio associati alla mortalità e alla durata di degenza. Materiali e metodi: Questo lavoro è uno studio multicentrico a cui hanno partecipato 14 terapie intensive pediatriche italiane, costituito da una parte retrospettiva e da una parte prospettica. Nello studio sono stati inclusi 538 pazienti ricoverati in terapia intensiva pediatrica tra gennaio 2019 e aprile 2022. La fase retrospettiva ha coinvolto 239 pazienti, mentre la prospettica 299. I dati registrati riguardano sia variabili relative alla fase precedente al ricovero in terapia intensiva che al ricovero in TIP stesso. Nel nostro lavoro sono state analizzate la popolazione generale dello studio, la popolazione di pazienti con tumore solido in rapporto a quella di pazienti con tumore ematologico e la popolazione di bambini trapiantati in rapporto ai bambini non trapiantati. I fattori di rischio per mortalità e durata di degenza relativi al pre-ricovero in TIP e alla degenza in TIP sono stati analizzati mediante analisi univariate e multivariate. Risultati: Tra i 538 pazienti inclusi nello studio il 54% erano maschi. L’età media è stata 7 anni (IRQ 2-12). Le diagnosi di malattia di base sono state le seguenti: tumore solido (51%), leucemia linfoblastica acuta (23%), leucemia mieloide acuta (6.2%), linfoma non Hodgkin (3.8%), linfoma di Hodgkin (6.1%), altro (15%). Il 19% dei pazienti erano stati sottoposti a trapianto di midollo. Le cause principali di ricovero sono state complicanze respiratorie (32%) e neurologiche (23%). La mortalità in terapia intensiva pediatrica è stata del 13%. 428 pazienti sono stati inclusi nelle analisi dei fattori di rischio per la mortalità in TIP e per la durata di degenza in TIP. Dall’analisi multivariata della mortalità sono risultate significative in pre-ricovero le seguenti variabili: HSCT (Hematopoietic Stem Cell Transplantation) (p=0.013), O-PEWS (Oncological Pediatric Early Warning Score) (p=0.010), PIM (Pediatric Index of Mortality) 3 score (p<0.001) and priorità (p=0.012); durante il ricovero le variabili: insufficienza multiorgano (p=0.004) e episodio di arresto cardiaco (p<0.001). Dall’analisi multivariata sulla durata della degenza in TIP è risultata significativa in pre-ricovero in TIP la variabile insufficienza multiorgano (p=0.049); durante la degenza le variabili: durata della ventilazione invasiva e/o non invasiva (p<0.001) e la presenza di NPT (p=0.004). Conclusioni: Il nostro studio riporta una minor mortalità dei pazienti pediatrici oncologici ricoverati in terapia intensiva rispetto agli studi presenti in letteratura. Il riconoscimento precoce dei pazienti a più alto rischio, un’appropriata tempistica nel ricovero in TIP ed un’adeguata terapia potrebbero migliorare ancora di più la sopravvivenza dei pazienti. Il O-PEWS e lo score PIM 3 sono importanti strumenti per determinare la gravità del paziente. Hanno inoltre significato predittivo per la mortalità. Sarebbero tuttavia necessari nuovi aggiornamenti delle linee guida riguardo i criteri di ricovero in TIP, l’appropriatezza e le tempistiche del supporto intensivo in modo da poter assicurare il miglior approccio interdisciplinare e, di conseguenza, migliorare la sopravvivenzaIn the past decades, important progresses have been made in pediatric oncology thanks to a deep understanding of cancer biology that allowed improving patients’ survival and ameliorating their outcomes through the implementation of optimized treatment protocols. However, children with cancer still develop serious complications related either to their disease or to its treatment and may require intensive care. Thus, pediatric oncologic patients and particularly those who also undergo allogeneic hematopoietic stem cell transplantation during their treatment course are to be considered as a high-risk population for intensive care needs. The most common causes for pediatric intensive care unit (PICU) admission in these patients are respiratory and neurological complications, as well as sepsis and multiorgan failure. PICU treatments include respiratory support with invasive and non-invasive ventilation, renal replacement therapy, total parenteral nutrition and eventually extracorporeal membrane oxygenation. Despite various scores have been historically developed to assess the severity of patients’ clinical conditions during their hospitalization, evaluate the actual need for PICU admission and predict mortality, recent and robust studies regarding PICU admitted oncologic children are lacking in the literature. Aim of the study: Our study is aimed at describing the pediatric oncologic population admitted to different Italian PICUs with regard to pre-PICU admission variables and during PICU stay variables. Our secondary endpoint is to identify risk factors associated with PICU mortality and length of PICU stay. Materials and methods: This work is a multicenter retrospective and prospective study involving 14 Italian PICUs. Data were collected from a total of 538 patients admitted to 14 Italian PICUs between January 2019 and April 2022. The retrospective phase involved 239 patients, the prospective phase 299 patients. the data collected include before PICU admission variables and during PICU stay variables. These variables were analysed to describe the overall population of the study, the subpopulations of patients with solid tumor compared to children affected by an hematological neoplasm, and the subpopulations of children who underwent stem cell transplant compared to non-transplanted children. Univariate and multivariate analyses were performed to identify pre PICU admission and PICU stay risk factors for mortality outcome and for length of PICU stay outcome. Results: The 54% of the 538 study patients were males. Median age was 7 years (IRQ 2-12). The underlying diagnoses were: solid tumor (51%), acute lymphoblastic leukemia (23%), acute myeloid leukemia (6.2%), non-Hodgkin lymphoma (3.8%), Hodgkin lymphoma (6.1%), others (15%). 19% of the patients underwent HSCT. The most common admission causes were respiratory failure (32%) and neurological deficits (23%). Mortality in PICU was 13%. 428 patients were included in the analysis of risk factors for mortality in PICU and PICU length of stay (patients admitted after surgery who stayed in PICU less than 48 hours were excluded). The multivariate analysis for risk factors associated with mortality outcome showed significant values for the following pre-PICU admission predictors: HSCT (Hematopoietic Stem Cell Transplantation) (p=0.013), O-PEWS (Oncological Pediatric Early Warning Score) (p=0.010), PIM (Pediatric Index of Mortality) 3 score (p<0.001) and priority level (severity of illness) (p=0.012); PICU stay predictors: multiorgan failure (p=0.004) and cardiac arrest (p<0.001). The multivariate analysis for risk factors associated with length of PICU stay showed significant values for multiorgan failure (p=0.049) as before PICU admission predictor; PICU stay predictors: invasive and/or non-invasive ventilation length (p<0.001) and TPN (p=0.004). Conclusions: Our study reports a lower mortality for pediatric oncologic patients admitted to PICU compared to literature

Damage-imperfection indicators for the assessment of multi-leaf masonry walls under different conditions

The complexity of multi-leaf masonry walls suggests further researches on the dy- namic behaviour mainly characterized by incoherent response between the different layers. The intrinsic discontinuity and the manufacturing imperfections are amplified by the incre- mental damage that triggers different failure mechanisms that affect the dynamic parameters, such as modal shapes, frequencies and damping ratios. The dynamic identification with out- put only methodology has been proposed in this work on different multi-leaf masonry walls subjected to uniaxial compressive load. The responses of full infill, damaged infill and strengthened infill masonry panels with different widespread damage have been recorded. The evolution of the damage scenario changes the modal shapes, the related frequencies and the damping ratios that through the comparison with the data of the initial conditions can de- tect the anomalies and then the intrinsic vulnerabilities. Through the curvature modal shape methods and the structural irregularity indices applied to different phases, it was possible evaluate the imperfection and the induced damage entity

Dynamic investigation on the Mirandola bell tower in post-earthquake scenarios

After the seismic events of the 20th and 29th of May 2012 in Emilia (Italy), most of the monumental and historic buildings of the area were severely damaged. In a few structures, partial collapse mechanisms were observed (e.g. façade tilting, out-of-plane overturning of panels…). This paper presents the case-study of the bell tower of the Santa Maria Maggiore cathedral, located in Mirandola (Italy). The dynamic response of the structure was evaluated through operational modal analysis using ambient vibrations, a consolidated non-destructive procedure that estimates the dynamic parameters of the bell-tower. The dynamic tests were carried out in pre-intervention and post-intervention conditions in order to understand the sensitivity of dynamic measurements to safety interventions. Furthermore, a comparative study is made with similar cases of undamaged masonry towers up to the 6th mode. Finally, an investigation on the state of connections and of the building itself is carried out via FE model updating

Buckling of built-up columns of pultruded fiber-reinforced polymer C-sections

This paper presents the test results of an experimental investigation to evaluate the buckling behavior of built-up columns of pultruded profiles, subjected to axial compression. Specimens are assembled by using four (off the shelf) channel shaped profiles of E-glass fiber-reinforced polymer (FRP), having similar detailing to strut members in a large FRP structure that was executed in 2009 to start the restoration of the Santa Maria Paganica church in L’Aquila, Italy. This church had partially collapsed walls and no roof after the April 6, 2009, earthquake of 6.3 magnitude. A total of six columns are characterized with two different configurations for the bolted connections joining the channel sections into a built-up strut. Test results are discussed and a comparison is made with closed-form equation predictions for flexural buckling resistance, with buckling resistance values established from both eigenvalue and geometric nonlinear finite element analyses. Results show that there is a significant role played by the end loading condition, the composite action, and imperfections. Simple closed-form equations overestimate the flexural buckling strength, whereas the resistance provided by the nonlinear analysis provides a reasonably reliable numerical approach to establishing the actual buckling behavior

Recursive partitioning and Gaussian Process Regression for the detection and localization of damages in pultruded Glass Fiber Reinforced Polymer material

In this paper, a methodology for the detection and localization of damages in composite pultruded members is proposed. This is particularly relevant to thin-walled pultruded members, which are typically characterized by orthotropic behavior, anisotropic along the fibers and isotropic in the cross section. Hence, a method to detect and localize damage, and the influence these might have on the performance of thin-walled Glass Fiber Reinforced Polymer (GFRP) members, is proposed and applied to both numerical and experimental data. Specifically, the numerical and experimental modal shapes of a narrow flange pultruded profile are analyzed. The reliability of the proposed semiparametric statistical method, which is based on Gaussian Processes Regression and Bayesian-based Recursive Partitioning, is analyzed on a narrow flange profile, artificially affected by sawed notches with incremental depth. The numerical investigation is carried out via finite element models (FEMs) of the cracked beam, where the dynamic parameters and the modal shapes are computed. In total, three different crack sizes are investigated, to compare the results with the experimental ones. Finally, the proposed approach is further extended and validated on numerically simulated frame structures

Faunes gravettiennes à grands mammifères de l’Italie du Sud : Grotta della Cala (Salerno) et Grotta Paglicci (Foggia)

Les couches gravettiennes de la grotte della Cala, sur la côte tyrrhénienne de l’Italie du sud, et de la grotte Paglicci, sur le versant adriatique, ont fourni des restes fauniques qui témoignent de deux réalités différentes. Dans la grotte della Cala, la chasse a été orientée essentiellement vers le Cerf, dont les restes atteignent 90 % du total. Les autres ongulés, avec une prédominance du Sanglier et du Chevreuil, ont été récupérés en quantités nettement inférieures. Par contre, dans la grotte Paglicci, les ongulés de milieux ouverts ou mixtes comme le Cheval, le Bouquetin ou l’Aurochs sont abondants et, au cours des différentes phases culturelles, leur variabilité quantitative est élevée. Les restes de ces deux sites appartiennent à des espèces d’ongulés probablement chassées en rapport étroit avec la possibilité de les rencontrer. La fréquence des différents taxons exprime donc l’étendue de leur habitat et les changements climatiques qui ont influé sur eux. Dans ces deux dépôts, au cours des mêmes phases chronologiques, des environnements et des conditions climatiques très différents ont constitué une diversité de substrats fauniques qui a probablement influencé les aspects culturels et technologiques des populations gravettiennes respectives.Faunal remains related to two different environments have been recovered from gravettian layers of Grotta della Cala, in the Tyrrhenian coast of southern Italy, and from Grotta Paglicci, in the Adriatic side. Data from Grotta della Cala attest an hunting principally aimed at Deer, whose remains constitute 90 % of the total. Other ungulates have been recovered in much smaller quantities, with a dominance of Roe deer and Wild boar. Ungulates typical of open or mixed environments, like Horse, Aurochs and Ibex, are instead abundant in faunal assemblage from Grotta Paglicci, and their quantities change according to different cultural phases. Bones collected from these two sites probably belong to ungulates hunted in proportion to their availability. Therefore, taxa frequencies show the effects of climate changes on faunal associations and the wideness of habitats. In each of these two deposits, during the same chronological phases, environmental and climate conditions have produced different faunal presences which probably have influenced cultural and technological aspects of the respective gravettian peoples

Faunes gravettiennes à grands mammifères de l’Italie du Sud : Grotta della Cala (Salerno) et Grotta Paglicci (Foggia)

Les couches gravettiennes de la grotte della Cala, sur la côte tyrrhénienne de l’Italie du sud, et de la grotte Paglicci, sur le versant adriatique, ont fourni des restes fauniques qui témoignent de deux réalités différentes. Dans la grotte della Cala, la chasse a été orientée essentiellement vers le Cerf, dont les restes atteignent 90 % du total. Les autres ongulés, avec une prédominance du Sanglier et du Chevreuil, ont été récupérés en quantités nettement inférieures. Par contre, dans la grotte Paglicci, les ongulés de milieux ouverts ou mixtes comme le Cheval, le Bouquetin ou l’Aurochs sont abondants et, au cours des différentes phases culturelles, leur variabilité quantitative est élevée. Les restes de ces deux sites appartiennent à des espèces d’ongulés probablement chassées en rapport étroit avec la possibilité de les rencontrer. La fréquence des différents taxons exprime donc l’étendue de leur habitat et les changements climatiques qui ont influé sur eux. Dans ces deux dépôts, au cours des mêmes phases chronologiques, des environnements et des conditions climatiques très différents ont constitué une diversité de substrats fauniques qui a probablement influencé les aspects culturels et technologiques des populations gravettiennes respectives.Faunal remains related to two different environments have been recovered from gravettian layers of Grotta della Cala, in the Tyrrhenian coast of southern Italy, and from Grotta Paglicci, in the Adriatic side. Data from Grotta della Cala attest an hunting principally aimed at Deer, whose remains constitute 90 % of the total. Other ungulates have been recovered in much smaller quantities, with a dominance of Roe deer and Wild boar. Ungulates typical of open or mixed environments, like Horse, Aurochs and Ibex, are instead abundant in faunal assemblage from Grotta Paglicci, and their quantities change according to different cultural phases. Bones collected from these two sites probably belong to ungulates hunted in proportion to their availability. Therefore, taxa frequencies show the effects of climate changes on faunal associations and the wideness of habitats. In each of these two deposits, during the same chronological phases, environmental and climate conditions have produced different faunal presences which probably have influenced cultural and technological aspects of the respective gravettian peoples

Sensitivity to damage imperfection for multileaf masonry walls based on vibrational analyses

Damage-imperfection indicators based on variation of dynamic parameters allow to identify the intrinsic discontinuity and the damage of structures. Here, the structural health monitoring through the vibration-based approach has been carried out by two steps on three different multileaf masonry specimens (full infill, damaged infill, and strengthened infill) subjected to uniaxial compressive load. In the first step, the characterization of initial conditions based on the investigation of the intrinsic discontinuity and the manufacturing imperfections has been done. In this phase, the detection, localization, assessment, and prediction of damage have been given by the comparison between the experimental and numerical modal data calculated by the commercial finite element code. Subsequently, in the second step, starting from the identification of undamaged condition, the damage effects on changes of the dynamic parameters have been recorded. As well known, the incoherent response between the leaves is related to frequency values, damping ratios, and modal shapes