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Occurrence, distribution and bibliography of the medicinal leech Hirudo verbana Carena, 1820 (Hirudinea, Hirudinidae) in Sicily (Italy)
The occurrence of the medicinal leech Hirudo verbana in the inland waters of Sicily has been lately overlooked. In the present note, the occurrence and distribution of this species is reviewed based both on the review of the available literature data and field collecting. Although a noteworthy reduction in the distribution range of the species seems to have taken place in Sicily in the course of the XX century, Hirudo verbana was confirmed to be still present in several sites located both within and out of Natura2000 sites. The Sicilian populations of the species should be included in the frame of the monitoring activities established by the Article 17 of the EU Council Directive 92/43/EEC (“Habitats Directive”)
Design aspects of a CMC coating-like system for hot surfaces of aero engine components
Ceramic Matrix Composite (CMC) is an emerging material system that can be a game changer in the aerospace industry, both civil and military. CMCs components are, in fact, lighter and less prone to fatigue failure in a high temperature environment. However, at high temperatures, the diffusion of oxygen and water vapour inside the CMC can have detrimental effects. Therefore, the presence of protective coating is necessary to extend the life of CMC components. In the present work, a three-layers coating, consisting of a silicon bond (BND), adhesively bonded to the CMC, an Environment Barrier Coating (EBC) and a softer layer 3 (LAY3), is investigated for a CMC component. An aero-engine high pressure turbine seal segment was considered. Two design aspects are covered: (i) creep law is determined and calibrated in environment Abaqus from the experimental data of each coating layer available in the open literature, to provide a suitable instrument for the creep relaxation analyses of hot components; (ii) thickness sensitivity study of each layer of the coating is conducted to minimise the interface stresses of coating with substrate in order to mitigate cracking and removal/spalling phenomena when exposed to temperature gradients and to increase their service life. These two different aspects are combined together to predict the coating stress field as a function of service time
AFM characterization of biomolecules in physiological environment by an advanced nanofabricated probe
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Using Thermal Gradient Measurements to Compare Bath Temperature and Agitation Effects on the Quenching Performance of Palm Oil, Canola Oil and a Conventional Petroleum Oil
A proprietary Liscic/Petrofer cylindrical Inconel 600 probe of 50-mm diameter and 200-mm length which was instrumented with three thermocouples on the same radius of the crosssection at the middle of the length was used to determine the differences in quenching performance of two vegetable oils, palm oil and canola oil, and they were compared to a locally produced conventional petroleum oil quenchant. The cooling curves and heat transfer performance of these oils were determined at different bath temperatures and agitation rates. The work was performed at the Quenching Research Centre located at the Faculty for Mechanical Engineering, University of Zagreb, Croatia. The results of this comparative study are reported herein
Social norms and problematic gaming among adolescents: The role of Internet use coping motives.
Problematic gaming (PG) is a public health issue among adolescents worldwide. Although several studies have documented that peer influences constitute a relevant risk factor for adolescent problematic behaviors, little research is currently available on PG. The aim of this study was to examine the contribution of social norms and perceived friends' gaming frequency on participants' own gaming frequency and PG, by testing potential differences among groups with low vs. high motive to use the Internet (e.g., online gaming) as a coping strategy. A survey was administered to 470 adolescent gamers (mean age = 15.49 years; SD = 1.05 years; 77.9 % males). A theoretical model was tested through path analysis and multi-group comparisons were performed. Path analysis revealed that social norms and perceived friends' gaming frequency were positively associated to participants' gaming behaviors and PG. Additionally, different patterns between groups emerged. Our findings confirmed the relative importance of peer influences on adolescents' gaming behaviors and PG and showed that adolescents who rely more on online gaming to cope with negative affect may be more vulnerable to social influence processes than other peers. These findings may provide useful indications for prevention programs targeting adolescent PG. [Abstract copyright: Copyright © 2023 Elsevier Ltd. All rights reserved.
Ossicular Chain Lesions in Tympanic Perforations and Chronic Otitis Media without Cholesteatoma
OBJECTIVE: The first aim was to determine the prevalence, kind, and functional effects on hearing of ossicular chain suffering (OCS) in chronic otitis without cholesteatoma (NCOM) and tympanic perforations (TP). The second aim was to correlate the findings with clinical parameters and hearing level.MATERIALS AND METHODS: The study group comprised 250 consecutive patients affected by NCOM and who were subjected to tympanoplasty and never operated on before. Each patient underwent preoperative pure tone audiometry. Ossicles were evaluated during surgery. The incidence of OCS in NCOM was reported in 15-62% of the patients.RESULTS: Ossicular chain suffering was found in 26 out of the 250 patients included in the overall sample (10%). It was found in 7% of the patients affected by TP without otorrhea and in 19% of the patients affected by chronic ear discharge with drum perforation. OCS was found most frequently in posterior eardrum perforations and in patients with bilateral disease. The incus was the ossicle most frequently interested by resorption (92% of the patients). The air conduction threshold and air bone gap were more impaired in NCOM than in TP.CONCLUSION: Ossicular chain damages in patients with non-cholesteatomatous middle ear pathologies are not frequent and are present in no more than 10% of the patients, but lesions found were similar to those reported in patients with cholesteatoma. Otorrhea, posterior perforation, and bilateral disease can be considered as good predictors of OCS
Vertigo returning to the sitting position after the Semont manoeuvre. Is it a prognostic symptom?
Thalassemic cardiomyopathy: Echocardiography difference between major and intermediate thalassemia at rest and during isometric effort: Yearly follow-up
Left ventricular (LV) performance was studied in young patients with severe chronic anemia due to beta-thalassemia major, intermedia, and in healthy control subjects. M-mode echocardiograms were recorded in each patient and semiautomatic computerized analysis of the tracings provided data relating to LV performance. Then a statistical analysis of the difference between each specific thalassemic group and the normal subjects was made using Student's t-test for unpaired data. The study showed that cardiac dysfunction is more serious in major than in intermediate beta thalassemia. A follow-up one year later showed a progressive deterioration of the cardiac indices, in spite of treatment with desferrioxamine. A handgrip test was performed in the follow-up study, which permitted us to distinguish different groups relative to the changes in LV performance indices. Our findings indicate that echocardiography provides a simple noninvasive means for assessing changes in the cardiac structure and function, which should also prove useful in the serial evaluation of patients at risk of developing myocardial iron deposition
Systematic Review and Meta-Analysis of Medication Reviews Conducted by Pharmacists on Cardiovascular Diseases Risk Factors in Ambulatory Care
Background Pharmacists-led medication reviews (MRs) are claimed to be effective for the control of cardiovascular diseases; however, the evidence in the literature is conflicting. The main objective of this meta-analysis was to analyze the impact of pharmacist-led MRs on cardiovascular disease risk factors overall and in different ambulatory settings while exploring the effects of different components of MRs. Methods and Results Searches were conducted in PubMed, Web of Science, Embase, the Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Library Central Register of Controlled Trials database. Randomized and cluster randomized controlled trials of pharmacist-led MRs compared with usual care were included. Settings were community pharmacies and ambulatory clinics. The classification used for MRs was the Pharmaceutical Care Network Europe as basic (type 1), intermediate (type 2), and advanced (type 3). Meta-analyses in therapeutic goals used odds ratios to standardize the effect of each study, and for continuous data (eg, systolic blood pressure) raw differences were calculated using baseline and final values, with 95% CIs. Prediction intervals were calculated to account for heterogeneity. Sensitivity analyses were conducted to test the robustness of results. Meta-analyses included 69 studies with a total of 11 644 patients. Sample demographic characteristics were similar between studies. MRs increased control of hypertension (odds ratio, 2.73; 95% prediction interval, 1.05-7.08), type 2 diabetes mellitus (odds ratio, 3.11; 95% prediction interval, 1.17-5.88), and high cholesterol (odds ratio, 1.91; 95% prediction interval, 1.05-3.46). In ambulatory clinics, MRs produced significant effects in control of diabetes mellitus and cholesterol. For community pharmacies, systolic blood pressure and low-density lipoprotein values decreased significantly. Advanced MRs had larger effects than intermediate MRs in diabetes mellitus and dyslipidemia outcomes. Most intervention components had no significant effect on clinical outcomes and were often poorly described. CIs were significant in all analyses but prediction intervals were not in continuous clinical outcomes, with high heterogeneity present. Conclusions Intermediate and advanced MRs provided by pharmacists may improve control of blood pressure, cholesterol, and type 2 diabetes mellitus, as statistically significant prediction intervals were found. However, most continuous clinical outcomes failed to achieve statistical significance, with high heterogeneity present, although positive trends and effect sizes were found. Studies should use a standardized method for MRs to diminish sources of these heterogeneities
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