46 research outputs found

    From Beam to Chassis: How to Increase NVH Performances with an Optimized Moment of Inertia Distribution

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    Car weight reduction is becoming more and more important for every kind of vehicle: minor mass implies, in fact, minor consumption, makes easier to fulfill homologation rules and assures a better handling behavior. Despite that, several vehicle missions have always been solved by adding more mass, e.g. NVH. In this paper, a methodology to optimize the stiffness distribution is proposed in order to obtain better vibrational performances without increasing the mass. At first, the problem has been solved for a simple beam using finite element and optimization algorithms. At a second stage, the optimal moment of inertia distribution found has been applied to a chassis thanks to a topometry optimization. Finally, the improvement in NVH performances has been verified comparing the inertances of the optimized model with those of the non-optimized one

    Structural optimization of automotive chassis: theory, set up, design

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    Improvements in structural components design are often achieved on a trial-and-error basis guided by the designer know-how. Despite the designer experience must remain a fundamental aspect in design, such an approach is likely to allow only marginal product enhancements. A different turn of mind that could boost structural design is needed and could be given by structural optimization methods linked with finite elements analyses. These methods are here briefly introduced, and some applications are presented and discussed with the aim of showing their potential. A particular focus is given to weight reduction in automotive chassis design applications following the experience matured at MilleChili Lab

    Estimate of tissue composition in malignant and benign breast lesions by time-domain optical mammography

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    partially_open10noThe optical characterization of malignant and benign breast lesions is presented. Time-resolved transmittance measurements were performed in the 630-1060 nm range by means of a 7-wavelength optical mammograph, providing both imaging and spectroscopy information. A total of 62 lesions were analyzed, including 33 malignant and 29 benign lesions. The characterization of breast lesions was performed applying a perturbation model based on the high-order calculation of the pathlength of photons inside the lesion, which led to the assessment of oxy- and deoxy- hemoglobin, lipids, water and collagen concentrations. Significant variations between tumor and healthy tissue were observed in terms of both absorption properties and constituents co ncentration. In particular, benign lesions and tumors show a statistically significant discrimination in terms of absorption at several wavelengths and also in terms of oxy-hemoglobin and collagen content.G. Quarto; L. Spinelli; A. Pifferi; A. Torricelli; R. Cubeddu; F. Abbate; N. Balestreri; S. Menna; E. Cassano; P. TaroniQuarto, Giovanna; Spinelli, Lorenzo; Pifferi, ANTONIO GIOVANNI; Torricelli, Alessandro; Cubeddu, Rinaldo; F., Abbate; N., Balestreri; S., Menna; E., Cassano; Taroni, Paol

    Morbidity and Mortality in Patients with Idiopathic Pulmonary Fibrosis Undergoing Diagnostic Surgical Lung Biopsy

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    Morbidity and Mortality In Patients With Idiopathic Pulmonary Fibrosis Undergoing Diagnostic Surgical Lung Biopsy.Previous studies have shown conflicting results about safety of surgical lung biopsy (SLB) in usual interstitial pneumonia (UIP)/idiopathic pulmonary fibrosis (IPF) patients. Study design: we performed a retrospective analysis of all patients who underwent SLB between 2003 and 2013 at the University Hospital of Modena (Italy), to assess morbidity and mortality among patients with UIP/IPF , as compared to patients with other diffuse parenchymal lung diseases (non UIP/IPF). Results: we analyzed 73 patients with (n=29) and without (n=44) UIP/IPF, in which medical history, histology, and survival status were collected. UIP/IPF was diagnosed according to international guidelines. In 59 patients lung biopsy was performed via video-assisted thoracoscopy; in 14 patients thoracotomy was conducted. No intraoperative complications were observed. Postoperative complications were not significantly different between groups and consisted of fever (n=1 in UIP/IPF group; n=4 in non-UIP/IPF group), pneumothorax (n=1 in non-UIP/IPF), pleural effusion (n=1 in non-UIP/IPF), and acute exacerbation (n=1 in both groups, who died). There was no 30-day, 60-day and 90-day mortality. Conclusions: we conclude that surgical lung biopsy can be safely performed in patients with suspected UIP/IPF

    Feeding Behaviour of Larval European Sea Bass (Dicentrarchus labrax L.) in Relation to Temperature and Prey Density

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    The feeding behaviour of larval European sea bass (Dicentrarchus labrax, L.) was analysed in relation to temperature and prey density under controlled laboratory conditions with the aim to assess the ability of larval fish to change the feeding tactic as a response to environmental changes. Larvae were acclimated for 20 days at three different temperatures (19, 22 and 26°C), and their feeding behaviour was then video-recorded in experimental trials, at two prey densities, consisting of swarms of 400/l and 1440/l Artemia nauplii. Results showed that there was a significant effect of the interaction between temperature and prey density on the proportion of swimming activity that was reduced at the high temperature-high prey density combination. This suggested a switching in the larval feeding behaviour from an active to an ambush tactic, when the temperature reached 26°C and the prey density was 1440 /l Artemia nauplii. These results are consistent with the current literature on fish larval behaviour in showing that the foraging tactic can be modulated by the interaction of different abiotic and biotic factors characterising the rearing environment

    HNF1B polymorphism influences the prognosis of endometrial cancer patients: A cohort study

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    Background: HNF1B (formerly known as TCF2) gene encodes for a transcription factor that regulates gene expression involved in normal mesodermal and endodermal developments. A close association between rs4430796 polymorphism of HNF1B gene and decreased endometrial cancer (EC) risk has been demonstrated. The aim of the current study was to test the hypothesis that rs4430796 polymorphism can influence the prognosis of EC patients. Methods: Retrospective cohort study. Clinical and pathological data were extrapolated and genotypes were assessed on formalin-fixed and paraffin-embedded non-tumour tissues. The influence of patients' genotype on overall survival and progression free survival were our main outcome measures. Results: A total of 191 EC patients were included in the final analysis. Overall survival differed significantly (P = 0.003) among genotypes. At multivariate analysis, a significant (P < 0.05) effect on overall survival was detected for FIGO stage, and rs4430796 polymorphism of HNF1B gene. After grouping EC patients according to adjuvant treatment, rs4430796 polymorphism resulted significantly (P < 0.001) related to overall survival only in subjects who received radiotherapy plus chemotherapy. A significant (P = 0.014) interaction between rs4430796 polymorphism and chemo-radiotherapy was also detected. Finally, only a trend (P = 0.090) towards significance was observed for rs4430796 polymorphism effect on progression free survival. Conclusions: rs4430796 polymorphism of HNF1B gene influences independently the prognosis of EC patients with a potential effect on tumor chemo-sensitivity

    Polymorphisms in cyclooxygenase-2 gene in endometrial cancer patients

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    The enzyme cyclooxygenase 2 is an inducible enzyme expressed at sites of inflammation and in a variety of malignant solid tumors such as endometrial cancer (EC). In EC patients, its over-expression is correlated with progressive disease and poor prognosis. The expression is encoded by a polymorphic gene, called PTGS2. The aim of the current study was to test the hypothesis that rs5275 polymorphism of PTGS2 influence the prognosis of EC patients. This paper is a retrospective cohort study. Clinical and pathological data were extrapolated and genotypes were assessed on formalin-fixed and paraffin-embedded non-tumor tissues. A total of 159 type I EC patients were included in the final analysis. Univariate analysis indicated that patients with rs5275 genotype CC have a lower risk to develop a grade (G) 2–3 endometrial cancer. rs5275 effect on EC grading was confirmed by multivariate analysis also after data adjusting for age, BMI, parity, hypertension, and diabetes. Adjusted odds ratio (OR) confirmed that patients with rs5275 genotype CC have a risk 80 % lower (OR = 0.20, P = 0.009) to develop a G2 and/or G3 EC in comparison with patients with TT or TC genotype. Differentiation of the type 1 EC is significantly and independently influenced by rs5275 polymorphism. rs5275 CC patients have a lower risk to present a G2–G3 EC

    A Single-Molecule Bioelectronic Portable Array for Early Diagnosis of Pancreatic Cancer Precursors

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    A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRASmut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 × 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRASmut, MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma.</p

    A Single-Molecule Bioelectronic Portable Array for Early Diagnosis of Pancreatic Cancer Precursors

    Get PDF
    A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRASmut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 × 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRASmut, MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma.</p

    Sport car space-frame chassis design in view of weight reduction

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    Road vehicle homologation has become more and more challenging due to the introduction of stringent regulations regarding pollutant emissions. In order to fulfil these requirements, the focus in automotive industry mainly settled on the improvement of the engine performance in terms of fuel consumption. Another design approach aims at the vehicle lightening, yet in the respect of the safety standards. In the present work a methodology for preliminary space-frame chassis design for rear-central engine sport cars is proposed. The purpose is to design a chassis able to attain given performance goals in view of weight reduction. The design problem is faced using finite element analysis. The chassis numerical model is made of shell elements and is split into three sub-models: front, central, and rear. This allows the parallelization of the work among different teams. The sub-models undergo topometry and size optimizations in order to asses the optimal shell thickness distribution
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