32 research outputs found

    Thermophysical, microstructural characterization and non-destructive control of TBCs by photothermal and thermographic techniques: some lessons learned

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    Since several years, photothermal and thermographic techniques have been used to perform the thermo-physical characterisation of TBCs and the non-destructive assessment of TBC integrity. Furthermore, in the last decade some attempts to use these techniques for carrying out a non-destructive microstructural characterization have been done, as well. In this talk the description of a thermographic technique able to simultaneously measure the through-the-thickness and the in-plane thermal diffusivity of free standing TBCs samples and thus giving evidence of the typical microstructural anisotropy of APS TBCs will be provided [1]. Furthermore, some effects of the laser radiation used in a laser flash experiment on the TBC thermal diffusivity and a new model for fitting the experimental data will be presented [2,3]. The main results of an activity focused to identify potentialities and limitations of using Laser flash experiments on multilayered samples for estimating thermal diffusivity of TBCs samples will be provided. A theoretical and experimental analysis of the real capabilities of infrared techniques to estimate the porosity content and the microstructure of porous ceramic materials such as thermal barrier coatings (TBCs) by studying thermal diffusivity variations when pores are filled with air or vacuum will be provided [4,5]. Please click Additional Files below to see the full abstract

    Clinical characteristics and prognostic impact of atrial fibrillation in patients with chronic heart failure

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    AIMS: To assess the prevalence, clinical characteristics and independent prognostic impact of atrial fibrillation (AF) in chronic heart failure (CHF) patients, and the potential protective effect of disease-modifying medications, particularly beta-blockers (BB). METHODS: We retrospectively reviewed the charts of patients referred to our center since January 2004, and collected all clinical information available at their first visit. We assessed mortality to the end of June 2015. We compared patients with and without AF, and assessed the association between AF and all-cause mortality by multivariate Cox regression and Kaplan-Meyer analysis, particularly accounting for ongoing treatment with BB. RESULTS: A total of 903 patients were evaluated (mean age 68\ub112 years, 73% male). Prevalence of AF was 19%, ranging from 10% to 28% in patients 6460 and 6577 years, respectively. Besides the older age, patients with AF had more symptoms (NYHA II-III 60 vs. 44%), lower prevalence of dyslipidemia (23 vs. 37%), coronary artery disease (28 vs. 52%) and left bundle branch block (9 vs. 16%). On the contrary, they more frequently presented with an idiopathic etiology (50 vs. 24%), a history of valve surgery (13 vs. 4%) and received overall more devices implantation (31% vs. 21%). The use of disease-modifying medications (i.e. BB and ACE inhibitors/angiotensin receptor blockers) was lower in patients with AF (72 vs. 80% e 71 vs. 79%, respectively), who on the contrary were more frequently treated with symptomatic and antiarrhythmic drugs including diuretics (87 vs. 69%) and digoxin (51 vs. 11%). At a mean follow-up of about 5 years, all-cause mortality was significantly higher in patients with AF as compared to those in sinus rhythm (45% vs. 34%, p value <0.05 for all previous comparisons). However, in a multivariate analysis including the main significant predictors of all-cause mortality, the univariate relationship between AF and death (HR 1.49, 95% CI 1.15-1.92) became not statistically significant (HR 0.98, 95% CI 0.73-1.32). Nonetheless, patients with AF not receiving BB treatment were found to have the worst prognosis, followed by patients with sinus rhythm not receiving BB therapy and patients with AF receiving BB therapy, who both had similarly worse survival when compared to patients with sinus rhythm receiving BB therapy. CONCLUSIONS: AF was highly prevalent and associated with older age, worse clinical presentation and underutilization of disease-modifying medications such as BB in a population of elderly patients with CHF. AF had no independent impact on mortality, but the underutilization of BB in this group of patients was associated to a worse long-term prognosis

    A rapid and reliable detection procedure of Atlantic trout introgression at the diagnostic lactate dehydrogenase chain-1 gene

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    The Italian-native Mediterranean brown trout (Salmo ghigii) is a seriously threatened freshwater fish, especially by anthropogenic hybridisation with the domestic strains of Atlantic origin that have been repeatedly released into the wild for angling. A PCR-restriction fragment length polymorphism (RFLP) assay of the diagnostic lactate dehydrogenase chain-1 (LDH-C1) gene sequences has been routinely applied to distinguish exotic from native brown trout lineages and detect Atlantic introgression signals in the Mediterranean wild populations. Here, we used dermal swab DNA obtained from 28 wild trout to improve laboratory procedures to genetically characterise trout samples at the LDH-C1gene through (1) a capillary electrophoresis analysis of the RFLP fragments and (2) the optimisation of a diagnostic single nucleotide polymorphism analysable through mini-sequencing approaches. The developed methods were fully consistent with those obtained through the traditional approach, but their analytical process is almost entirely automated and digitalised, thus improving result readability and accuracy in the detection of alien introgressed traces in wild Mediterranean brown trout populations

    THE CHECK-LIST OF THE ITALIAN FRESHWATER FISH FAUNA

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    The results of the Working Group (WG) on the Systematics and Nomenclature of the italian freshwater fish species established within the A.I.I.A.D. are showed. WG, in about four years of activities, focused on the current taxonomic situation of Italian fish species (Cyclostomes and Bony Fishes), with special reference to the doubtful cases, in the light of the most recent scientific findings. The considerable amount of literature data collected allowed us to clarify the different points of view expressed by the authors who over time contributed to the deepening of knowledge. The Check-list of the Italian freshwater fish fauna could be a useful tool to reach a shared starting point to fill the existing knowledge gaps. Moreover, this need arises from the awareness that the presence of a univocal scientific nomenclature could play a key role in improving the conservation status of the native fish fauna. Finally, we believe that the scientific debate that will hopefully arise, as well as from the activities within WG, also from the presentation of the results to the Association, can represent a useful moment of comparison and cultural growth of all members. The Check-list with the proposed nomenclature for the Italian freshwater fish fauna, the notes drafted for each of the taxa examined (over 80), the sheets with the minutes of each of the discussion sessions carried out, and the archive including all the literature data collected represent useful tools that, through the website (http://www.aiiad.it), will become a shared heritage of the Association

    Prognostic value of reduced heart rate reserve during exercise in hypertrophic cardiomyopathy

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    Background: Sympathetic dysfunction can be evaluated by heart rate reserve (HRR) with exercise test. Objectives: To determine the value of HRR in predicting outcome of patients with hypertrophic cardiomyopathy (HCM). Methods: We enrolled 917 HCM patients (age = 49 +/- 15 years, 516 men) assessed with exercise stress echocardiography (ESE) in 11 centres. ESE modality was semi-supine bicycle in 51 patients (6%), upright bicycle in 476 (52%), and treadmill in 390 (42%). During ESE, we assessed left ventricular outflow tract obstruction (LVOTO), stress-induced new regional wall motion abnormalities (RWMA), and HRR (peak/rest heart rate, HR). By selection, all patients completed the follow-up. Mortality was the predetermined outcome measure Results: During ESE, RWMA occurred in 22 patients (2.4%) and LVOTO (>= 50 mmHg) in 281 (30.4%). HRR was 1.90 +/- 0.40 (lowest quartile 2.13). Higher resting heart rate (odds ratio 1.027, 95% CI: 1.018-1.036, p < 0.001), older age (odds ratio 1.021, 95% CI: 1.009-1.033, p < 0.001), lower exercise tolerance (mets, odds ratio 0.761, 95% CI: 0.708-0.817, p < 0.001) and resting LVOTO (odds ratio 1.504, 95% CI: 1.043-2.170, p = 0.029) predicted a reduced HRR. During a median follow-up of 89 months (interquartile range: 36-145 months), 90 all-cause deaths occurred. At multivariable analysis, lowest quartile HRR (Hazard ratio 2.354, 95% CI 1.116-4.968 p = 0.025) and RWMA (Hazard ratio 3.279, 95% CI 1.441-7.461 p = 0.004) independently predicted death, in addition to age (Hazard ratio 1.064, 95% CI 1.043-1.085 p < 0.001) and maximal wall thickness (Hazard ratio 1.081, 95% CI 1.037-1.128, p < 0.001). Conclusions: A blunted HRR during ESE predicts survival independently of RWMA in HCM patients.info:eu-repo/semantics/publishedVersio

    Prophylactic role of acetyl-l-carnitine on knee lesions and associated pain in a rat model of osteoarthritis.

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    Aims: in the present study, our aim was to validate in vivo the prophylactic role of acetyl-l-carnitine (ALC) using an established knee osteoarthritis (OA) animal model which mimics the pathological changes of OA in humans, targeting cartilage and causing chondrocyte death. Main methods: animal model was obtained by an intra-articular injection of monosodium iodoacetate (MIA) into rat femorotibial joint space. Pain was measured in animals submitted to MIA model by paw pressure and compression behavioral tests in the presence or absence of ALC. Key findings: morphological analysis of knee-joint from MIA and ALC co-treated rats showed that the total pathological score attributed to histological findings was dramatically lower in rats treated with MIA in the presence of ALC. OA chondrocyte overexpression of pathogenic collagenase matrix-metallopeptidase-13 (MMP13) could be decreased in knee-cartilage from MIA/ALC rats; whereas type II collagen (COL2) expression level could be partially increased to control value. ALC twice daily treatment was able to attenuate pain in OA rat knee as revealed by mechanical behavioral tests. Significance: in our experiments, pain that is usually associated with OA, was correlated with the severity of histopathological findings. Our findings show that there is a place for ALC as chondroprotective agents in cartilage degradation and strongly support the prophylactic and therapeutic potentials of ALC in knee-OA patients
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