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Within the framework of Gaussian graphical models, a prior distribution for the underlying graph is introduced to induce a block structure in the adjacency matrix of the graph and learning relationships between fixed groups of variables. A novel sampling strategy named Double Reversible Jumps Markov chain Monte Carlo is developed for block structural learning, under the conjugate G-Wishart prior. The algorithm proposes moves that add or remove not just a single link but an entire group of edges. The method is then applied to smooth functional data. The classical smoothing procedure is improved by placing a graphical model on the basis expansion coefficients, providing an estimate of their conditional independence structure. Since the elements of a B-Spline basis have compact support, the independence structure is reflected on well-defined portions of the domain. A known partition of the functional domain is exploited to investigate relationships among the substances within the compound.

Manganese is a paramagnetic element suitable for magnetic resonance imaging (MRI) of neuronal function. However, high concentrations of MnThis work focuses on the development of precise simulations and models to compare theThe nuclear code Talys has been employed to optimize theGood agreement was obtained between cross-section calculations and measurements. The comparison of the two reaction channels suggests thatBoth

Motivated by the analysis of spectrometric data, a Gaussian graphical model for learning the dependence structure among frequency bands of the infrared absorbance spectrum is introduced. The spectra are modeled as continuous functional data through a B-spline basis expansion and a Gaussian graphical model is assumed as a prior specification for the smoothing coefficients to induce sparsity in their precision matrix. Bayesian inference is carried out to simultaneously smooth the curves and to estimate the conditional independence structure between portions of the functional domain. The proposed model is applied to the analysis of infrared absorbance spectra of strawberry purees. Università Cattolica del Sacro Cuore, Italy

Recently, scandium-47 has attracted attention in the scientific community thanks to its promising features, making it suitable for targeted radiotherapy and theranostic applications, also in combination with the β+ emitters 43Sc/44Sc. However, in view of possible pre-clinical and clinical studies, finding efficient production routes is still a current research topic. In this work we investigate 47Sc cyclotron production using proton beams on enriched titanium targets. The analysis of the cross sections and yields of both 47Sc (T1/2 = 3.35 d) and its main contaminant 46Sc (T1/2 = 83.79 d) has been performed with the nuclear reaction code Talys (v.1.95). The experimental data (scarce and relatively old) are compared with model calculations and some discrepancies emerge even after the tuning of parameters defining the nuclear level densities, involved in the compound nucleus formation. The 49Ti case allows a more precise cross sections reproduction, conversely the 50Ti case requires further theoretical investigations. Preliminary yields analysis has been carried out for both 47Sc and 46Sc.

The proton-induced reaction on natural vanadium targets is studied for the production of the innovative theranostic radionuclide 47Sc as well as of its contaminants, mainly 46Sc. The theoretical excitation functions are calculated using the nuclear reaction code TALYS and are compared with the most recent experimental data. A better agreement between the theoretical curves and the data is achieved with an optimization of the nuclear level density parameters. The obtained improvements represent a useful and important result for accurate evaluations of yields and purities which are needed quantities for subsequent dosimetric studies, in view of the radiopharmaceutical applications of 47Sc. The optimization procedure is explained and shown for 47Sc and 46Sc, and also a comparison among the theoretical and experimental cumulatives is given (for the main contaminant) in addition to an estimation of the production yields for two irradiation conditions for both nuclides.

The 52gMn radionuclide is suitable for the innovative MultiModal Imaging technique, and in particular for a PET/MRI scan, due to its physical properties. The standard cyclotron-based production of 52gMn relies on the nuclear reaction NatCr(p,x)52gMn, but we have investigated theoretically the possibility of an alternative and competitive route, the reaction NatV(α,x)52gMn, which has not been considered for this purpose so far. By using the nuclear reaction code TALYS, we found some discrepancies between the theoretical calculations of the cross sections and the corresponding experimental data. Therefore we tuned the parameters governing the nuclear level densities in the microscopic models implemented in TALYS, thus improving the agreement with the data. Then, by studying the cross sections for 52gMn and its contaminants, we have identified an optimal energy window for the production of high purity 52gMn, around 40 MeV. We have also calculated the time evolution of the number of nuclei of the different Mn isotopes, for an irradiation in this energy window, finding that this route is expected to lead to a higher yield and Radionuclidic Purity with respect to the standard reaction with NatCr. The study suggests the reaction NatV(α,x)52gMn as a promising alternative route for the production of 52gMn.

Femoral periprosthetic fractures in hip surgery still represent a difficult surgical procedure and a secure optimal treatment has not been found yet. Great help is provided by the development of commonly used classifications such as the Vancouver classification and the recent Unified Classification System (UCS), which introduce clearer fracture patterns with the respective surgical indications. The most discussed pattern is related to category B of both classifications in which, despite the use of established treatment paradigms, results are poor or otherwise unpredictable. This study reviews the literature related to the analysis of fractures and its following treatment.

In recent years, Computational Thinking (CT) made its way into K-12 as a key set of 21st-century skills. However, the issue of assessing student's learning of CT remains a challenging one: it is indeed not clear how to achieve a comprehensive evaluation that is able to assess not only the technical and domain-specific skills, but also the domain-independent meta-skills of CT. Finding a solution to this issue is crucial, because assessment not only determines whether or not educational goals are being met, but also supports the design of a curriculum. Multiple forms of assessments have been proposed within the main perspective of programming skills, neglecting the possible generalization of CT training on other skills. In this work, we first review the existing approaches to CT assessment. Then, we discuss what non-technical skills (relational skills and cognitive life-skills) should be included in a comprehensive CT assessment framework. Moreover, we provide an indication of possible solutions to capitalize on the existing experiences in order to achieve a feasible integration of different types of assessment.

We report the status of the pre-experimental phase of a project called "Combining Computational Thinking Didactics and Software Engineering in K-12" (COCONATS), which aims at combining computational thinking and software engineering didactics in order to facilitate the acquisition of software engineering principles in K-12, while promoting the development of life-skills.

In this paper we describe and analyze a new user interface program that allows students of nursery and primary schools to use digital microscopes in the Linux environment. Moreover, we want to provide teachers with new ideas for a conscious and effective use of digital microscopes in order to promote the interest toward the scientific exploration of nature in children.In our classes we have used the Intel® Play™ QX3™ Microscope, which is a unique tool to introduce children to technology. This microscope has technical features that make it very effective and simple to use; furthermore it allows, in combination with our software, to observe very small objects directly from the computer screen and realize videos by capturing images in long term experiments.Children can recombine the microscope images so as to produce new graphic objects, modify these images in a creative way and create new multimedia collections of their experiments. In particular, we aim at establishing a link among practical experience, geometry and artistic education; moreover, this tool can facilitate the integration of certified students, hyperactive students and students with deficit and attention disorder, since it can promote their concentration through an operative approach.

In this pilot study we used a proteomic approach to compare the urinary protein patterns of healthy smokers and non-smokers. Proteins were resolved by two-dimensional gel electrophoresis and identified by mass spectrometry. The relative abundance of three inflammatory proteins (S100A8, inter-alpha-trypsin inhibitor heavy chain 4, CD59) and that of two isoforms of pancreatic alpha amylase was significantly higher in smokers. Zinc-alpha-2-glycoprotein was the only protein down-regulated in smokers. Its abundance was significantly correlated with urinary glucocorticoids. Most of the proteins identified may be non-specific biomarkers of tobacco effects, since they are involved in inflammatory responses associated with several diseases. Of greater interest are the changes in abundance of pancreatic alpha amylase and zinc-alpha-2-glycoprotein, which after proper validation, might be candidate biomarkers of diseases resulting from exposure to tobacco smoke. The data also show for the first time that smoking can affect the expression profile of urinary proteins.

Background Colorectal cancer is one of the major causes of cancer mortality world-wide. Prevention would improve if at-risk subjects could be identified. The aim of this study was to characterise plasma protein biomarkers associated with the risk of colorectal cancer in samples collected prospectively, before the disease diagnosis. Methods After an exploratory study on the comprehensive plasma proteome analysis by liquid chromatography-tandem mass spectrometry from ten colorectal cancer cases enrolled at diagnosis, and ten matched controls (Phase 1), a similar preliminary study was performed on prospective plasma samples from ten colorectal cancer cases, enrolled years before disease development, and ten matched controls identified in a nested case–control study within the Florence cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC) study (Phase 2); in Phase 3 the validation of the candidate biomarkers by targeted proteomics on 48 colorectal cancer cases and 48 matched controls from the Florence-EPIC cohort, and the evaluation of the disease risk were performed. Results Systems biology tools indicated that both in the Phase 1 and Phase 2 studies circulating protein levels differing in cases more than 1.5 times from controls, were involved in inflammation and/or immune response. Eight proteins including apolipoprotein C-II, complement C4-B, complement component C9, clusterin, alpha-2-HS-glycoprotein, mannan-binding lectin serine-protease, mannose-binding protein C, and N-acetylmuramoyl-L-alanine amidase were selected as promising candidate biomarkers. Targeted proteomics of the selected proteins in the EPIC samples showed significantly higher clusterin levels in cases than controls, but only in men (mean ± SD, 1.98 ± 0.46 and 1.61 ± 0.43 nmol/mL respectively, Mann–Whitney U, two-tailed P = 0.0173). The remaining proteins were unchanged. Using multivariate logistic models a significant positive association emerged for clusterin, with an 80% increase in the colorectal cancer risk with protein’s unit increase, but only in men. Conclusions The results show that plasma proteins can be altered years before colorectal cancer detection. The high circulating clusterin in pre-diagnostic samples suggests this biomarker can improve the identification of people at risk of colorectal cancer and might help in designing preventive interventions. Electronic supplementary material The online version of this article (doi:10.1186/s12885-015-1058-7) contains supplementary material, which is available to authorized users.

Udgivelsesdato: 2008-Feb-14 In contrast to some extensively examined food mutagens, for example, aflatoxins, N-nitrosamines and heterocyclic amines, some other food contaminants, in particular polycyclic aromatic hydrocarbons (PAH) and other aromatic compounds, have received less attention. Therefore, exploring the relationships between dietary habits and the levels of biomarkers related to exposure to aromatic compounds is highly relevant. We have investigated in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort the association between dietary items (food groups and nutrients) and aromatic DNA adducts and 4-aminobiphenyl-Hb adducts. Both types of adducts are biomarkers of carcinogen exposure and possibly of cancer risk, and were measured, respectively, in leucocytes and erythrocytes of 1086 (DNA adducts) and 190 (Hb adducts) non-smokers. An inverse, statistically significant, association has been found between DNA adduct levels and dietary fibre intake (P = 0.02), vitamin E (P = 0.04) and alcohol (P = 0.03) but not with other nutrients or food groups. Also, an inverse association between fibre and fruit intake, and BMI and 4-aminobiphenyl-Hb adducts (P = 0.03, 0.04, and 0.03 respectively) was observed. After multivariate regression analysis these inverse correlations remained statistically significant, except for the correlation adducts v. fruit intake. The present study suggests that fibre intake in the usual range can modify the level of DNA or Hb aromatic adducts, but such role seems to be quantitatively modest. Fibres could reduce the formation of DNA adducts in different manners, by diluting potential food mutagens and carcinogens in the gastrointestinal tract, by speeding their transit through the colon and by binding carcinogenic substances.

The aim of this study was to evaluate whether biomarkers of environmental tobacco smoke exposure [i.e., 4-aminobiphenyl-hemoglobin (4-ABP-Hb) adducts] were predictive of the risk of tobacco-related cancers and diseases. We did a case-control study nested within the European Prospective Investigation into Cancer and Nutrition, involving 190 controls and 149 cases (incident cancer of the lung, bladder, pharynx, larynx, oral cavity, leukemias, and chronic obstructive pulmonary disease or emphysema deaths). All individuals were never smokers or ex smokers for >10 years. 4-ABP-Hb adducts were analyzed in peripheral blood collected before the onset of the disease (median, 7 years). Overall, 4-ABP-Hb adducts were higher, although not statistically significantly so, in cases (as a whole) than controls. In the control population, high fruit and vegetable consumption significantly lowered the frequency of detectable adducts (Fisher's exact test, P = 0.025). Restricting the analysis to women, 4-ABP-Hb adducts were higher in cases than controls (Mann-Whitney P = 0.036) and the odds ratio (OR) for the presence/absence of adducts was 2.42 [95% confidence interval (95% CI), 1.18-4.98]. Moreover, the association of adducts with the individual cancer types was stronger in women than in the whole study population, although statistically significant only for leukemias (OR, 2.77; 95% CI, 1.06-7.20). The results provide some evidence that women may be more susceptible to environmental tobacco smoke, as suggested by their higher adduct levels. The most important finding of this prospective study is that, at least in women, 4-ABP-Hb adducts may help identify subjects at high risk of cancers related to environmental tobacco smoke exposure.