226 research outputs found
Family History of Breast, Ovarian and Endometrial Cancer and Risk of Breast Cancer
The relationship between family history of breast, ovarian and endometrial cancer and risk of breast cancer was analysed using data from a case-control study of breast cancer conducted in the greater Milan area, Northern Italy. The cases studied were 3415 women (median age 52 years, range 23-74) who had histdogically confirmed breast cancer diagnosed within the year precedmg the interview. The controls were 2916 women (median age 54 years; range 21-74] In hospital for a spectrum of acute illnesses excluding gynaecological, hormonal or neoplastic conditions. A total of 375 cases (11.0%) and 128 controls (4.4%) reported a history of breast cancer in first degree relatives. Compared with women with no family history of breast cancer, the RR was 2.7 (95% confidence Interval [CI] : 2.2-3.3) in those with one first degree relative affected and 2.8 (95% CI : 1.3-5.7) in those with two or more affected relatives. In comparison with women without family history of ovarlan cancer the RR of breast cancer was 1.4 (95% CI : 0.9-2.3) for those reporting one or more first degree relatives with ovarian cancer. However, the multivariate estimate for family history of ovarian cancer, including a term for familial breast cancer, decreased to 0.8 (95% CI : 0.5-1.4). The risk of breast cancer was similar in women reporting a family history of breast cancer (RR=2.2) and in those reporting a family history of both breast and ovarian cancer (RR=2.51, in cornparkon with women reporting no family history of breast and/or ovarian cancer. When tlia relation with family history of breast cancer was analysed in strata of women with and without family history of ovarian cancer, no difference was found in the RR estimates: the RR for family history of breast cancer was 2.8 in women with family history of ovarian cancer and 2.7 in those without history of ovarian cancer. No relation was found between history of endometrial cancer in first degree relatives and risk of breast cance
MDO applications to conventional and novel turboprop aircraft within agile European project
In this paper, multidisciplinary design optimization within the AGILE European project is applied to two turboprop aircraft. The first one is a conventional configuration characterized by wing mounted engines, while the second one is an innovative configuration with rear engines installation on the horizontal tail tip with an innovative power plant architecture. Both configurations are suited for 90 passengers, a design range of 1200 nautical miles and a cruise Mach number equal to 0.56.
The methodologies used to analyze both configurations include aerodynamic performance in clean, landing and takeoff configurations, mission performance, weight and balance, stability and control, emissions, in terms of Global Warming Potential parameter, and Direct Operating Cost estimation. The latest two will be considered as objective functions for the optimization loop. Aim of this paper is to compare both configurations highlighting benefits and limits. Particular attention has been posed on the innovative approach used to analyze the use cases. The whole design process is made up ofdifferent tools belonging to a specific partner. Each partner is specialized in a specific discipline. The design process has been setup to be completely automated so that, partners, distributed worldwide are able to communicate
and exchange results through remote connection. In this way each discipline has been assigned to the suited specialist
Laser texturing of a multilayer DLC from nano-liquid-diamond precursors via microsecond laser pulses
Diamond Like Carbon (DLC) coatings have well known mechanical properties, including high hardness, chemical stability, optical transparency and biocompatibility. In addition they are frequently used in multilayer coating systems.
Laser surface texturing of DLC coatings can be a tailoring solution to optimize the coating functional parameters like roughness, wettability, wear, corrosion resistance, etc. Furthermore, compared to mechanical grinding, local laser removal could be a suitable technology for repairing locally damaged coated parts (i.e. worn surfaces, corroded surfaces, etc.)
In the present work, laser surface texturing and controlled laser removal of a multilayer DLC coating obained from nano-liquid-diamond precursors have been studied using a 8W Q-switched laser (λ=532 nm) with microsecond pulses. Textured ablation as well as full planar decoating are shown through proper adjustment of laser texturing parameters
Risk Factors for Spontaneous Abortion
A case-control study was conducted to evaluate risk factors for spontaneous abortions. Cases were 94 women with two or more unexplained miscarriages (after exclusion of genetic, endocrine and Müllerian factors) and no term pregnancy, controls were 176 women admitted for normal delivery to the same clinic where cases were identified. Questions were asked about personal characteristics and habits, and gynaecological history. A family history of recurrent miscarriage was more common among women with spontaneous miscarriages than among the controls (13 cases versus 8 controls, relative risk (RR) =3.2, 95% confidence interval (CI) = 1.3-8.1). Compared to women whose menarche occurred at age 11 or younger, the RRs were 0.8 when menarche occurred at age 12-13 and 0.5 at age 14 or more: this trend in risk was statistically significant. Compared with never smokers, current smokers had about a 40% increased risk of miscarriage and the risk increased with number of cigarettes per day. No association emerged with socio-demographic characteristics (e.g. education, marital status, age of the partner), reproductive history (age at first pregnancy), type of contraceptive used and other general lifestyle habits (e.g. alcohol or coffee consumption
Morphology and paleobiology of the Late Cretaceous large-sized shark Cretodus crassidens (Dixon, 1850) (Neoselachii; Lamniformes)
The definition of the Cretaceous shark genus Cretodus Sokolov, 1965 is primarily based on isolated teeth. This genus includes five species. Among these, Cretodus houghtonorum Shimada and Everhart, 2019 is the only species based on a partially preserved skeleton. Here, the taxonomic attribution of a virtually complete skeleton of Cretodus from the Turonian of northeastern Italy is discussed, together with a few specimens from the Turonian of England. One of the latter is investigated through micropaleontological analysis to determine its stratigraphic position. The material is referred to Cretodus crassidens (Dixon, 1850), the diagnosis of which is emended herein. The dentition is tentatively reconstructed, exhibiting strong similarities with congeneric species, although it differs in having strong vertical folds on the main cusp labial face, a mesiodistally broad tooth aspect, weak and well-spaced 'costulae' at crown base, and a different dental formula in the number of parasymphyseal and lateral rows. Some tooth malformations are interpreted as feeding-related or senile characters. The Italian specimen suggests that Cretodus crassidens had a wide and laterally expanded mouth and head, a stout body, and attained a gigantic size. Cretodus crassidens was a moderate-speed swimming shark ecologically like the extant tiger shark Galeocerdo cuvier (Péron and Lesueur in Lesueur, 1822). The age estimate from vertebral-band counting suggests that the Italian individual was at least 23 years old and the growth model indicates a longevity of 64 years and a maximum attainable total length of 9-11 m. Cretodus crassidens occurs both in Boreal and Tethyan domains, implying a broad paleobiogeographic distribution and a preference toward offshore settings
Risk Factors for Spontaneous Abortion
A case-control study was conducted to evaluate risk factors for spontaneous abortions. Cases were 94 women with two or more unexplained miscarriages (after exclusion of genetic, endocrine and M\ufcllerian factors) and no term pregnancy, controls were 176 women admitted for normal delivery to the same clinic where cases were identified. Questions were asked about personal characteristics and habits, and gynaecological history. A family history of recurrent miscarriage was more common among women with spontaneous miscarriages than among the controls (13 cases versus 8 controls, relative risk (RR) = 3.2, 95% confidence interval (CI) = 1.3-8.1). Compared to women whose menarche occurred at age 11 or younger, the RRs were 0.8 when menarche occurred at age 12-13 and 0.5 at age 14 or more: this trend in risk was statistically significant. Compared with never smokers, current smokers had about a 40% increased risk of miscarriage and the risk increased with number of cigarettes per day. No association emerged with sociodemographic characteristics (e.g. education, marital status, age of the partner), reproductive history (age at first pregnancy), type of contraceptive used and other general lifestyle habits (e.g. alcohol or coffee consumption)
Game theory and evolutionary algorithms applied to MDO in the AGILE European project
In this paper, an optimization technique in aircraft design field, based on game theory and evolutionary algorithms to define the key variables for Multi-Disciplinary aircraft Optimization (MDO) into AGILE (Aircraft 3rd Generation MDO for Innovative Collaboration of Heterogeneous Teams of Experts) European project, is presented. This work represents one of the contributions given by UniNa (University of Naples “Federico II”) research group within the AGILE project, which is coordinated by the DLR and funded by EU through the project HORIZON 2020 that aims to create an evolution of MDO, promoting a novel approach based on collaborative remote design and knowledge dissemination among various teams of experts. Since the aircraft design field is very complex in terms of number of involved variables and the dimension of the space of variation, it is not feasible to perform an optimization process on all the design parameters; this leads to the need to reduce the number of the parameters to the most significant ones. A multi-objective optimization approach allows many different variables, which could be a constraint or an objective function for the specific investigation; thus, setting the constraints and objectives to reach, it is possible to perform an optimization process and control which parameters significantly affect the final result. Within AGILE project, UniNa research group aims to perform wing optimization processes in a preliminary design stage, coupling Nash game theory (N) with typical genetic evolutionary algorithm (GA), reducing computational time and allowing a more realistic association among objective functions and variables, to identify the main ones that significantly affect final result and that consequently must be considered by the partners of the AGILE consortium to perform MDO in the final part of project, applying the proposed optimization technique to novel aircraft configuration
Investigation of mechanical properties of AlSi3Cr alloy
In the present paper, microstructural and mechanical properties of an innovative AlSi3Mg alloy were studied. Particularly, the effect of the addition of Cr and Mn on tensile strength and impact toughness was evaluated. In fact, the presence of these elements leads to the formation of an intermetallic phase with a globular or polyhedral morphology. It was therefore investigated the role played by Cr-Mn containing particles in the failure mechanism and the influence of the heat treatment parameters. Moreover, tensile and impact tests were performed on A356 samples in T6 condition, whose results were compared with the performance of the innovative alloy. Considering the static properties, the innovative alloy showed remarkable values of tensile strength, while ductility was improved only after heat treatment optimization. Poor impact toughness values were measured and the microstructural analysis confirmed the presence of coarse intermetallics, acting as crack initiation and propagation particles, on the fracture surfaces
tensile behavior and impact toughness of an alsi3mgcr alloy
Abstract: Recently, an innovative AlSi3Mg alloy with Cr and Mn additions was developed for the production of truck wheels by means of a non-conventional hybrid technique, which combines features of both low pressure die casting and forging processes. The presence of both Cr and Mn leads to the formation of an intermetallic phase rich in Cr, Mn and Fe with a globular or dendritic morphology. Furthermore, proper solution treatments cause the formation of dispersoids in the aluminium matrix. These dispersoids are responsible of enhancing the alloy performance due to dispersion hardening mechanism. In the present work, the tensile properties and the impact toughness of the alloy in as-cast and different heat-treated conditions were studied. Moreover, tensile and impact strength tests were performed on A356 samples in T6 condition machined from traditional LPDC wheels, whose results were compared with the performance of the innovative alloy. Fracture surfaces of tensile and Charpy specimens were observed by Scanning Electron Microscopy (SEM) in order to identify the role of the Cr-Mn containing intermetallic particles in the failure mechanism and the influence of the heat treatment parameters. Considering the static properties, the innovative alloy showed remarkable values of tensile strength, while ductility was improved only after heat treatment optimization. Poor impact toughness values were measured and the microstructural analysis confirmed the presence of coarse intermetallic secondary phases, acting as crack initiation and propagation particles, on the fracture surfaces
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