University of Siena

About: University of Siena is a education organization based out in Siena, Italy. It is known for research contribution in the topics: Population & Cancer. The organization has 12179 authors who have published 33334 publications receiving 1008287 citations. The organization is also known as: Università degli studi di Siena & Universita degli studi di Siena.

Research Paper Recommender Systems: A Random-Walk Based Approach

Abstract: Every day researchers from all over the world have to filter the huge mass of existing research papers with the crucial aim of finding out useful publications related to their current work. In this paper we propose a research paper recommending algorithm based on the Citation Graph and random-walker properties. The PaperRank algorithm is able to assign a preference score to a set of documents contained in a digital library and linked one each other by bibliographic references. A data set of papers extracted by ACM Portal has been used for testing and very promising performances have been measured.

Microplastics induce transcriptional changes, immune response and behavioral alterations in adult zebrafish

Abstract: Microplastics have become pervasive environmental pollutants in both freshwater and marine ecosystems. The presence of microplastics have been recorded in the tissues of many wild fish species, and laboratory studies have demonstrated that microplastics can exert adverse health effects. To further investigate the biological mechanisms underlying microplastics toxicity we applied an integrated approach, analyzing the effects of microplastics at transcriptomic, histological and behavioral level. Adult zebrafish have been exposed to two concentrations of high-density polyethylene and polystyrene microplastics for twenty days. Transcriptomic results indicate alterations in the expression of immune system genes and the down-regulation of genes correlated with epithelium integrity and lipid metabolism. The transcriptomic findings are supported by tissue alterations and higher occurrence of neutrophils observed in gills and intestinal epithelium. Even the daily rhythm of activity of zebrafish appears to be affected, although the regular pattern of activity is recovered over time. Considering the transcriptomic and histological findings reported, we hypothesize that the effects on mucosal epithelium integrity and immune response could potentially reduce the organism defense against pathogens, and lead to a different utilization of energy stores.

Measurement of the rapidity and transverse momentum distributions of Z bosons in pp collisions at √(s)=7TeV

Abstract: Measurements of the normalized rapidity (y) and transverse momentum (qT) distributions of Drell-Yan muon and electron pairs in the Z-boson mass region (60

Interactions of lichens with heavy metals

Abstract: Recent developments in knowledge about the interactions between lichens and heavy metals at different levels, from populations to cells and from ecology to molecular biology are reviewed. Sources of heavy metals, mechanisms of heavy metal accumulation and detoxification by lichens are discussed. Special emphasis is placed on ultrastructural changes as well as physiological parameters such as membrane integrity, pigment composition, chlorophyll a fluorescence, photosynthesis, respiration, contents of ATP, amino acids, ergosterol, ethylene, non-protein thiols, activity of antioxidant enzymes and expression of stress proteins.

Sonographic endometrial thickness: a useful test to predict atrophy in patients with postmenopausal bleeding. An Italian multicenter study

Abstract: Eighteen centers took part in this prospective study into which 930 eligible patients were recruited. The selection criteria for admission were atypical bleeding after at least 6 months of postmenopausal amenorrhea, and absence of hormonal therapies for at least 6 months. The sonographic measurement of the maximum bi-endometrial thickness was made in a longitudinal plane. Sonographic measurements were always performed within 3 days prior to histological evaluation. In these patients the mean number of years from menopause (25-75th centile) was 6 (range 2-16). The prevalence of endometrial carcinoma was 11.5% and the prevalence of atrophy was 49.2%. The area under the receiver operator characteristic curves generated by sonographic thickness measurements reached the level of 85%, both for cancer and atrophy. The likelihood ratio for cancer, yielded by an endometrial thickness of 4.0 mm yielded a sensitivity for the detection of cancer of 98% and a negative predictive value of 99%. The overall sensitivity and positive predictive value for atrophy achieved by this cut-off were 57.2% and 87.3%, respectively. A multivariate logistic model showed that age and body mass index were independent variables associated with a significantly higher risk of endometrial cancer. The post-test probabilities for cancer and atrophy were recalculated on the basis of the integration of age, body mass index and endometrial thickness. The estimated reduction of invasive procedures on the basis of this integration was 31%. Transvaginal sonographic measurement of endometrial thickness, integrated with individual risk factors, can help in the management of postmenopausal patients with atypical bleeding, with regard to either the need for histological evaluation in high risk cases, or the choice of possible expectant management. We have shown that an endometrial thickness of < or = 4.0 mm safely predicts endometrial atrophy and justifies expectant management when the patient understands the need for proper follow up. This could be achieved with a reduction in the use of invasive procedures without unwanted delay in cancer diagnosis.