918 research outputs found

    Influence of interface ply orientation on delamination growth in composite laminates

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    The standard experimental procedures for determining the interlaminar fracture toughness are designed for delamination propagation in unidirectional specimens. However, in aerospace structural components, delamination usually occurs between plies at different orientations resulting in different damage mechanisms which can increase the value of the fracture toughness as the delamination propagates. Generally, numerical analyses employ the value measured at the delamination onset, leading to conservative results since the increase resistance of the delamination is neglected. In this paper, the fracture toughness and the R-curves of carbon/epoxy IM7/8552 are experimentally evaluated in coupons with delamination positioned at 0°/0° and 45°/−45° interfaces using Double Cantilever Beam (DCB) and Mixed-Mode Bending (MMB) tests. A simplified numerical approach based on the Virtual Crack Closure Technique (VCCT) is developed to simulate variable fracture toughness with the delamination length within a Finite Element code using a predefined field variable. The results of the numerical analyses compared with the experimental data in terms of load-displacement curves demonstrate the effectiveness of the proposed technique in simulating the increase resistance in delamination positioned between plies at 45°/−45° interface

    Surface Brightness Fluctuations from archival ACS images: a stellar population and distance study

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    We derive Surface Brightness Fluctuations (SBF) and integrated magnitudes in the V- and I-bands using Advanced Camera for Surveys (ACS) archival data. The sample includes 14 galaxies covering a wide range of physical properties: morphology, total absolute magnitude, integrated color. We take advantage of the latter characteristic of the sample to check existing empirical calibrations of absolute SBF magnitudes both in the I- and V-passbands. Additionally, by comparing our SBF and color data with the Teramo-SPoT simple stellar population models, and other recent sets of population synthesis models, we discuss the feasibility of stellar population studies based on fluctuation magnitudes analysis. The main result of this study is that multiband optical SBF data and integrated colors can be used to significantly constrain the chemical composition of the dominant stellar system in the galaxy, but not the age in the case of systems older than 3 Gyr. SBF color gradients are also detected and analyzed. These SBF gradient data, together with other available data, point to the existence of mass dependent metallicity gradients in galaxies, with the more massive objects showing a non--negligible SBF versus color gradient. The comparison with models suggests that such gradients imply more metal rich stellar populations in the galaxies' inner regions with respect to the outer ones.Comment: ApJ Accepte

    THE BOTANICAL GARDEN \u201cBERNARDINO DA UCRIA\u201d IN THE NATURAL PARK OF THE NEBRODI (SICILY) AND ITS MISSION TO CONSERVE, EXPLOIT AND SPREAD LOCAL AGROBIODIVERTITY AND OFFICINAL PLANTS

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    In Sicily, the academic botanical gardens of Catania, Messina and Palermo have been historically exerting a multiplicity of activities ranging from maintenance of ex situ collections to plant conservation policy, practice and ecological restoration, along with more traditional functions related to education and academic research. In the last decade\u2019s, two new botanical gardens the \u201cNuova Gussonea\u201d and the \u201cBernardino da Ucria, were created in Sicily, with the aim to play more delimited, yet modern and complementary roles. The garden \u201cNuova Gussonea\u201d, within the Etna Natural Park, is mostly devoted to collect and preserve the native flora of the Mount Etna, with a special focus on endemic and rare plants and their promotion to a wider public. The garden \u201cBernardino da Ucria\u201d, in the Nebrodi Natural Park, is mainly specialized in promoting the local culture and to collect and preserve the agro-biodiversity of officinal plants in the Nebrodi territory. It is located in the homonymous village in the Messina district where the famous \u201cdemonstrator of plants\u201d and co founder of the Botanical Garden of Palermo University was born. Noteworthy, within Sicily the Nebrodi area is undoubtedly the widest and richest in traditional activities regarding agriculture, sheep farming and sylviculture, which produced an agrobiodiversity heritage often representative of individual community cultures. Initially promoted by Palermo University and sustained by the Nebrodi Regional Park, this garden comprises the \u201cBanca vivente del Germoplasma vegetale dei Nebrodi\u201d. Accessions conserved in vivo so far include cultivars of crops (Corylus, Pyrus, Malus, Prunus sp. pl, Ficus, Juglans), vegetables (Phaseolus and Lycopersicum) and officinal plants, that are in part representative of local agricultural practices. Among crops, the collections of Ficus, Pyrus and Corylus are remarkable; while among vegetables, the beans (Phaseolus) are represented by over 65 distinct cultivars, comprising 57 climbing and 8 dwarf species (1). Additionally, the garden\u2019s bank hosts several botanical collections unrelated to the local flora, representative of officinal and ornamental genus, such as Salvia, Helleborus, Paeonia and Camelia. The cryopreserved accessions so far encompass the bean cultivars, mainly found within the Nebrodi Park area. The aim of this particular collection is to further exploit the local agricultural and food heritage by recovering and spreading among local farmers of autochthonous cultivars under extinction risk. Moreover, the garden has recently been equipped with a molecular biology laboratory, performing studies on the genetic diversity of the accessions, as well as activities instrumental to the creation of a related DNA bank, interconnected with the Palermo Botanical garden bank (HBP-Bank). In 2011, the botanical garden of Ucria hosted the Summer School \u201cKnowledge, conservation and management of plant biodiversity of the Mediterranean mountain systems\u201d, organized by Palermo University together with OPTIMA, and financially sponsored by the Nebrodi Park. Similarly, the Summer School \u201cManagement of plant biodiversity in the Mediterranean: ex situ conservation and germplasm banks\u201d will be held in 2016. The activities of the new Ucria botanical garden and its germplasm bank, is supported by a dedicated Consortium, established by the Nebrodi Park together with Palermo University. The botanical garden \u201cBernardino da Ucria\u201d is open to public in the spring and summer period. It is also offering didactic visits for educational purposes to several schools

    Prevalence of adenomyosis in endometrial cancer patients: a systematic review and meta-analysis

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    Introduction: Several studies have assessed the histological co-existence of endometrial carcinoma (EC) and adenomyosis. However, the significance of this association is still unclear. Objective: To assess the prevalence of adenomyosis in women with EC for a better understanding of the association between the two diseases. Materials and methods: A systematic review and meta-analysis was performed by searching electronics databases from their inception to March 2020, for all studies that allowed extraction of data about prevalence of adenomyosis in EC patients. Adenomyosis prevalence was calculated for each included study and as pooled estimate, with 95% confidence interval (CI). Results: Eight retrospective cohort studies assessing 5573 EC patients were included in our analysis. Of total, 1322 were patients with adenomyosis, and 4251 were patients without adenomyosis. Pooled prevalence of adenomyosis in EC patients was 22.6% (95% CI 12.7–37.1%). Conclusion: Adenomyosis prevalence in EC patients was not different from that reported for other gynecological conditions. The supposed association between the two diseases appears unsupported

    The Cepheids of NGC1866: A Precise Benchmark for the Extragalactic Distance Scale and Stellar Evolution from Modern UBVI Photometry

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    We present the analysis of multiband time-series data for a sample of 24 Cepheids in the field of the Large Magellanic Cloud cluster NGC1866. Very accurate BVI VLT photometry is combined with archival UBVI data, covering a large temporal window, to obtain precise mean magnitudes and periods with typical errors of 1-2% and of 1 ppm, respectively. These results represent the first accurate and homogeneous dataset for a substantial sample of Cepheid variables belonging to a cluster and hence sharing common distance, age and original chemical composition. Comparisons of the resulting multiband Period-Luminosity and Wesenheit relations to both empirical and theoretical results for the Large Magellanic Cloud are presented and discussed to derive the distance of the cluster and to constrain the mass-luminosity relation of the Cepheids. The adopted theoretical scenario is also tested by comparison with independent calibrations of the Cepheid Wesenheit zero point based on trigonometric parallaxes and Baade-Wesselink techniques. Our analysis suggests that a mild overshooting and/or a moderate mass loss can affect intermediate-mass stellar evolution in this cluster and gives a distance modulus of 18.50 +- 0.01 mag. The obtained V,I color-magnitude diagram is also analysed and compared with both synthetic models and theoretical isochrones for a range of ages and metallicities and for different efficiencies of core overshooting. As a result, we find that the age of NGC1866 is about 140 Myr, assuming Z = 0.008 and the mild efficiency of overshooting suggested by the comparison with the pulsation models.Comment: 13 pages, 10 figures, accepted in MNRAS (2016 January 14

    Awareness of energy drink intake guidelines and associated consumption practices: a cross-sectional study

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    BACKGROUND: Despite concern regarding harms of energy drink (ED) consumption, no research has been conducted to determine awareness and compliance with ED intake guidelines displayed on product packaging in Australia (a novel approach internationally). METHODS: A convenience sample of 1922 people completed an online survey. Participants reported their knowledge of maximum recommended daily ED intake according to Australian guidelines. RESULTS: Guideline awareness was reported by 38, 23 and 19 % of past year consumers, lifetime, and non-consumers, respectively. Amongst past year consumers, \u27accurate estimators\u27 reported greater ED intake and were more likely to exceed intake guidelines and consume alcohol mixed with ED (AmED). After controlling for demographics and frequency of use, guideline awareness predicted increased likelihood of exceeding guidelines in ED sessions, but was not associated with exceeding ED guidelines in AmED sessions. CONCLUSIONS: Australia is considered to have the most stringent regulatory approach to EDs internationally. However, advisory statements are not associated with greater awareness and compliance with intake guidelines. Failure to comply with standards for efficacious product labelling, and absence of broader education regarding guidelines, needs to be addressed

    Clinical characteristics of patients with endometrial cancer and adenomyosis

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    open11noA better endometrial cancer (EC) prognosis in patients with coexistent adenomyosis has been reported. Unfortunately, it is still unclear if this better prognosis is related to a more favorable clinical profile of adenomyosis patients. We aimed to evaluate differences in the clinical profiles of EC patients with and without adenomyosis. A systematic review and meta-analysis was performed by searching seven electronics databases for all studies that allowed extraction of data about clinical characteristics in EC patients with and without adenomyosis. Clinical characteristics assessed were: age, Body Mass Index (BMI), premenopausal status, and nulliparity. Mean difference in mean ± standard deviation (SD) or odds ratio (OR) for clinical characteristics between EC patients with and without adenomyosis were calculated for each included study and as a pooled estimate, and graphically reported on forest plots with a 95% confidence interval (CI). The Z test was used for assessing the overall effect by considering a p value < 0.05 as significant. Overall, eight studies with 5681 patients were included in the qualitative analysis, and seven studies with 4366 patients in the quantitative analysis. Pooled mean difference in mean ± SD between EC women with and without adenomyosis was −1.19 (95% CI: −3.18 to 0.80; p = 0.24) for age, and 0.23 (95% CI: −0.62 to 1.07; p = 0.60) for BMI. When compared to EC women without adenomyosis, EC women with adenomyosis showed a pooled OR of 1.53 (95% CI: 0.92 to 2.54; p = 0.10) for premenopausal status, and of 0.60 (95% CI: 0.41 to 0.87; p = 0.007) for nulliparity. In conclusion, there are not significant differences in clinical characteristics between EC patients with and without adenomyosis, with the exception for nulliparity. Clinical features seem to not underlie the better EC prognosis of patients with adenomyosis compared to patients without adenomyosis.openCasadio P.; Raffone A.; Maletta M.; Travaglino A.; Raimondo D.; Raimondo I.; Santoro A.; Paradisi R.; Zannoni G.F.; Mollo A.; Seracchioli R.Casadio P.; Raffone A.; Maletta M.; Travaglino A.; Raimondo D.; Raimondo I.; Santoro A.; Paradisi R.; Zannoni G.F.; Mollo A.; Seracchioli R
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