3,393 research outputs found

    Effect of airborne particle abrasion on microtensile bond strength of total-etch adhesives to human dentin

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    Aim of this study was to investigate a specific airborne particle abrasion pretreatment on dentin and its effects on microtensile bond strengths of four commercial total-etch adhesives. Midcoronal occlusal dentin of extracted human molars was used. Teeth were randomly assigned to 4 groups according to the adhesive system used: OptiBond FL (FL), OptiBond Solo Plus (SO), Prime & Bond (PB), and Riva Bond LC (RB). Specimens from each group were further divided into two subgroups: control specimens were treated with adhesive procedures; abraded specimens were pretreated with airborne particle abrasion using 50 mu m Al2O3 before adhesion. After bonding procedures, composite crowns were incrementally built up. Specimens were sectioned perpendicular to adhesive interface to producemultiple beams, which were tested under tension until failure. Data were statistically analysed. Failure mode analysis was performed. Overall comparison showed significant increase in bond strength (p < 0.001) between abraded and no-abraded specimens, independently of brand. Intrabrand comparison showed statistical increase when abraded specimens were tested compared to no-abraded ones, with the exception of PB that did not show such difference. Distribution of failure mode was relatively uniform among all subgroups. Surface treatment by airborne particle abrasion with Al2O3 particles can increase the bond strength of total-etch adhesive

    The nuclear-cytoplasmic trafficking of a chromatin-modifyng and remodelling protein (KMT2C), in osteosarcoma

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    Osteosarcoma is the most common paediatric primary non-hematopoietic bone tumor; the survival is related to the response to chemotherapy and development of metastases. KMT2C is a chromatin-modifying and remodelling protein and its expression has never been studied in osteosarcoma. The aim of this study was to understand the role of KMT2C in the osteosarcoma carcinogenesis and metastatic progression to identify a new molecular target and to provide new therapeutic approach. We performed the immunohistochemical and gene expression analysis of KMT2C in 32 samples of patients with diagnosis of osteosarcoma with known clinicpathological data and we analysed the expression of genes involved in the metastatic pathway in four osteosarcoma cell lines by blocking the KMT2C expression using siRNA. We found a nuclear-cytoplamic trafficking of KMT2C and the cytoplasmic localization was higher than the nuclear localization (p < 0.0001). Moreover, the percentage of cells with cytoplasmic positivity increased from low grade primary tissue to metastatic tissues. The cytoplasmic localization of KMT2C could lead to a change in its function supporting osteosarcoma carcinogenesis and progression. Our hypothesis is that KMT2C could affect the enhancer activity of genes influencing the invasive properties and metastatic potential of osteosarcoma

    Neural correlates of outcome of the psychotherapy compared to antidepressant therapy in anxiety and depression disorders: a meta-analysis

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    The most prevalent mental disorders, anxiety and depression, are commonly associated with structural and functional changes in the fronto-limbic brain areas. The clinical trials investigating patients with affective disorders showed different outcome to different treatments such as psychotherapy or pharmacotherapy. It is, however, still unexplored how these interventions approach affect the functional brain. This meta-analysis aims to compare the effects of psychotherapy compared to antidepressant therapy on functional brain activity in anxiety and depression disorders. Twenty-one samples with psychotherapy and seventeen samples with antidepressant therapy were included. The main finding showed an inverse effect of the two treatments on the right paracingulate activity. The patients undergoing psychotherapy showed an increase in the right paracingulate activity while pharmacological treatment led to a decrease of activation of this area. This finding seems to support the recent studies that hypothesize how psychotherapy, through the self-knowledge and the meaning processing, involves a top-down emotional regulation

    Minimal flavor-changing Zâ€ČZ' models and muon g−2g-2 after the RK∗R_{K^*} measurement

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    There has been a steady interest in flavor anomalies and their global fits as ideal probes of new physics. If the anomalies are real, one promising explanation is a new Zâ€ČZ' gauge boson with flavor-changing coupling to bottom and strange quarks and a flavor-conserving coupling to muons and, possibly, electrons. We point out that direct production of such a Zâ€ČZ', emerging from the collision of bb and ss quarks, may offer a complementary window into these phenomena because collider searches already provide competitive constraints. On top of that, we analyse the same Zâ€ČZ' scenario in relation to another long-standing discrepancy between theory and experiment that concerns the anomalous magnetic moment of the muon. By scanning the allowed Zâ€ČZ' coupling strengths in the low-mass region, we assess the compatibility of the signals from LHCb with the Zâ€ČZ' searches in the high energy LHC data and the measurements of the anomalous magnetic moment of the involved leptons. We also argue that observations of the latter can break the degeneracy pattern in the Wilson coefficients C9C_9 and C10C_{10} presented by LHCb data. The Zâ€ČZ' model we consider is compatible with the new measurement of RK∗R_{K^*}, therefore it can potentially account for the long-standing deviations observed in BB-physics.Comment: 13 pages, 5 figures. Missing factors corrected in eqs. 2.7-2.9 with slight updates in fig.

    Molecular profile of sensitization in subjects with short occupational exposure to latex

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    Objectives: We examined the prevalence of latex allergy in subjects with occupational exposure to latex allergens for less than 5 years, determining the disease spectrum in symptomatic workers. We identified the most frequent molecular allergens by Immuno- CAP (ICAP), correlating the findings with skin prick test (SPT) results. Material and Methods: Seven hundred twenty-three healthcare students using latex gloves on a regular basis were invited to participate in a baseline questionnaire screening. An ICAP serum test was performed only when a possible latex allergy was indicated by the questionnaire. Results: The total number of participants responding to the baseline survey was 619. Glove-related symptoms were indicated by 4% (N = 25) of the students. The most common symptom was contact dermatitis (N = 18, 72%). In 12 subjects, ICAP revealed a real sensitization to latex, with a recombinant latex allergen profile showing a high frequency for rHev b 6.01 specific immunoglobulin E (sIgE) (N = 9, 67%). In these individuals, skin symptoms were more prevalent than other types (88%). Conclusions: The combined positivity for rHev b 6.01, rHev 8 and rHev b 5 determined by ICAP identified 92% of latex-allergic subjects with short-term exposure to latex

    Optimized design of obstacle sequences for microfluidic mixing in an inertial regime

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    Mixing is a basic but challenging step to achieve in high throughput microfluidic applications such as organic synthesis or production of particles. A common approach to improve micromixer performance is to devise a single component that enhances mixing through optimal convection, and then sequence multiple such units back-to-back to enhance overall mixing at the end of the sequence. However, the mixing units are often optimized only for the initial non-mixed fluid composition, which is no longer the input condition for each subsequent unit. Thus, there is no guarantee that simply repeating a single mixing unit will achieve optimally mixed fluid flow at the end of the sequence. In this work, we analyzed sequences of 20 cylindrical obstacles, or pillars, to optimize the mixing in the inertial regime (where mixing is more difficult due to higher PĂ©clet number) by managing their interdependent convection operations on the composition of the fluid. Exploiting a software for microfluidic design optimization called FlowSculpt, we predicted and optimized the interfacial stretching of two co-flowing fluids, neglecting diffusive effects. We were able to quickly design three different optimal pillar sequences through a space of 32^(20) possible combinations of pillars. As proof of concept, we tested the new passive mixer designs using confocal microscopy and full 3D CFD simulations for high PĂ©clet numbers (Pe ≈O(10^(5-6)), observing fluid flow shape and mixing index at several cross-sections, reaching mixing efficiencies around 80%. Furthermore, we investigated the effect of the inter-pillar spacing on the most optimal design, quantifying the tradeoff between mixing performance and hydraulic resistance. These micromixer designs and the framework for the design in inertial regimes can be used for various applications, such as lipid nanoparticle fabrication which has been of great importance in vaccine scale up during the pandemic

    Novel Aspects of Classification, Prognosis and Therapy in Takotsubo Syndrome

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    Takotsubo syndrome (TTS) can be considered a transient form of acute heart failure that mimics an acute coronary syndrome. Although many hypotheses have been formulated, the precise physiopathology of TTS remains unknown. TTS is associated with a heterogeneous clinical course, which ranges from benign to poor outcome, comprising life-threatening phenotypes. In the acute phase, TTS patients may experience complications including left ventricular outflow tract obstruction, cardiogenic shock, arrhythmias and thromboembolic events. Furthermore, after the acute episode, physiological abnormalities can persist and some patients continue to suffer cardiac symptoms. To recognise patients at higher risk earlier, many variables have been proposed and risk stratifications suggested. There is no solid evidence regarding specific therapy and the proper management of TTS patients, either in the acute phase or long term. This review describes the current knowledge regarding diagnostic criteria, prognosis and therapy in TTS

    Implementation of a new automatic blending detection procedure in modern diesel engines by means of direct measurement of the indicated mean effective pressure

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    Within the cooperative research project DAX605 between GM Powertrain Europe and Istituto Motori - CNR, the capability to develop a method (economic and simple) for on-board biodiesel blending detection was studied. The method is based on the direct measurement of the Indicated Mean Effective Pressure (IMEP). The present research report summarizes the main results of this activity. The study was carried out on a 2.0L 4-cylinder “torque-controlled” Euro 5 diesel engine for passenger car (PC) application. This engine, equipped with instrumented glow plug for combustion closed loop control, represents the state of the art of the diesel engine control technology. Two biodiesels were chosen for the experiments: a Rapeseed-Methyl-Ester (RME) and an aged RME, while the conventional diesel fuel was an European (EU) certification diesel fuel. Results indicate generally a good response in blending detection of the method. However, in order to attain an acceptable accuracy, a pre-calibration appears necessary
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