109 research outputs found
Enabling technologies for future learning scenarios: the semantic grid for human learning
In this paper, starting from the limitations and
constrains of traditional human learning approaches, we
outline new suitable approaches to education and
training in future knowledge based society. In our vision,
learning and teaching are no longer standalone activities
but complex, conversational and experiential-based
processes implying collaboration, direct experience,
mutual trust and shared interests. We identify
characteristics of the environments suitable for these
processes, and we compare different enabling technology
infrastructures in order to justify why the Semantic Grid
for Human Learning, that is a particular enhanced
instance of the traditional Semantic Grid, is the most
appropriate infrastructure to build our vision on. Finally,
we present a realistic learning scenario as a case study,
proving the effectiveness of our innovative learning
approachesforfuture Education and Training
A Cultural Re-mediation Model for Storytelling in Pre-school Education
The use of the emotional language of stories and the amplification of the empathic driver thanks to the identification with story characters, makes the storytelling a valuable educational approach, especially for children. In accordance with embodied and situated cognition theories, manipulative storytelling proposes interactive environments where it is also possible for learners to manipulate the story through objects and tangible interfaces. In line with this vision, we propose in this paper a new model enabling the design and the execution of educational stories for children aged from 3 to 6. Stories are seen as sequences of missions: game experiences where children can interact to reach the educational objective. A re-mediation strategy, able to adapt the story on three different axis (immediacy-hypermediation, similarity-dissimilarity and aggregation-disaggregation) on the basis of assessment results, is also presented. A proof of concept based on the popular Brother Grimm's Hansel and Gretel tale is then discussed to demonstrate the capabilities of the model in the construction and deconstruction of the building blocks of a story
Sex difference in the interaction of alcohol intake, hepatitis B virus, and hepatitis C virus on the risk of cirrhosis
Background
The joint effect of the interaction of alcohol intake, hepatitis B virus (HBV) and hepatitis C
virus (HCV) on the risk of cirrhosis is still unexplored because a large sample size is required
for this investigation.
Objective
Evaluation of interaction of HBV, HCV and alcohol abuse on the risk of cirrhosis.
Design
We analysed 12,262 consecutive patients with chronic liver disease of various aetiologies referring to 95 Italian liver units in 2001 or 2014. To evaluate the interaction between alcohol abuse,
HBV infection, and HCV infection, patients unexposed to either factors were used as reference
category. Adjustment for BMI and age was done by multiple logistic regression analysis.
Results
Females were older than males (p<0.01) and less frequently showed HBV and alcoholic
aetiology (p<0.01). In both sexes, an overtime increasing age and an increasing proportion
of subjects with liver cirrhosis was observed, reflecting a better survival (0.01).An additive interaction is observed in females: the O.R. generated by the simultaneous
presence of HBV, HCV, and alcohol (5.09; 95% C.I. 1.06–24.56) exceeds the sum (4.14) of
the O.R. generated by a single exposure (O.R. = 0.72 for HBsAg positivity, OR = 1.34 for antiHCV positivity, and O.R. = 2.08 for alcohol intake). No interaction is observed in male sex.
Conclusions
The observed gender difference suggests that the simultaneous presence of HBV/HCV
coinfection and risky alcohol intake enhances the mechanism of liver damage to a greater
extent in females than in males
Análises U-Th-Pb (Shrimp) em titanitas: técnicas analíticas e exemplos em terrenos do sul-sudeste brasileiro – Instituto de Geociências da Universidade de São Paulo
Several titanite crystals were collected at Khan copper mine, Namibia, Africa. These crystals were analyzed using the Sensitive High Resolution Ion Microprobe (SHRIMP) method at the High-Resolution Geochronology Laboratory (GEOLAB), at Geoscience Institute of the University of São Paulo (IGc-USP), to be used as a reference in determining the 206Pb/238U ratios of unknown samples. In this experiment, the BLR-1 standard (1047 Ma) was used as reference, and an age of 519 Ma was obtained for the Khan internal standard. This value is very close to the ages mentioned in the literature: 207Pb/206Pb age of 518 ± 2 Ma and 522.3 ± 2.3 Ma (Thermal Ionization Mass Spectrometry – TIMS) and concordia age of 516.9 Ma (LA-ICP-MS). Analytical tests (SHRIMP dating) were conducted in titanites from two samples of granitic rocks from the Rio Piên Suite, which is considered to be a magmatic arc that bounds Curitiba and Luis Alves Terranes (South-Southeast of Brazil). The ages of 594 ± 5 Ma and 616.6 ± 2.6 Ma were obtained for samples MJ-649 and OM-629, respectively. These ages are very close to U-Pb ages measured for zircons using TIMS and SHRIMP dating. The errors for U-Pb ages in titanites are usually higher than those for U-Pb ages in zircons, which is explained by the higher concentration of common Pb in titanites. To obtain an acceptable analytical precision, more measurements are necessary. In relatively young crystals (post-Neoproterozoic Era), 207Pb/206Pb ages are very inaccurate as a consequence of the high concentration of common Pb in titanites, but, on the other hand, 206Pb/238U ages are very significant. Analyses of titanite using SHRIMP method at the GEOLAB-IGc-USP are very important, mainly when examined together with U-Pb ages for zircons and Ar-Ar ages for minerals, such as biotite and amphibole. This data allows the conduction of a precise geochronological study and the obtainment of important thermochronological data related to the uplift/denudation of rock bodies.Inúmeros cristais de titanita foram coletados na mina de cobre Khan, Namíbia, África. Eles foram analisados através da técnica de microssonda iônica de alta resolução e de alta sensibilidade (SHRIMP) no Laboratório de Geocronologia de Alta Resolução (GEOLab), do Instituto de Geociências da Universidade de São Paulo (IGc-USP), numa tentativa de serem utilizados como referência na determinação de razões 206Pb/238U de amostras desconhecidas. Neste experimento, foi utilizado como referência o padrão BLR1 (1.047 Ma), obtendo-se para o padrão interno Khan idade de 519 Ma. Tal valor é muito próximo das idades disponíveis na literatura especializada: idade 207Pb/206Pb de 518 ± 2 Ma e 522,3 ± 2,3 Ma (espectrômetro de massa de ionização térmica – Tims) e idade concórdia de 516,9 Ma (LA-ICP-MS). Os testes analíticos SHRIMP foram realizados em titanitas provenientes de duas amostras de rochas graníticas da Suíte Rio Piên, admitida como possível arco magmático, que baliza os terrenos Curitiba e Luis Alves (sul-sudeste brasileiro). A amostra MJ-649 acusou idade de 594 ± 5 Ma, e a amostra OM-629, idade de 616,6 ± 2,6 Ma. Tais valores são muito próximos às idades U-Pb obtidas em zircão através das técnicas SHRIMP e TIMS. Os erros obtidos nas idades U-Pb em titanitas são normalmente mais elevados que os obtidos em zircão em função da maior presença de Pb comum nas titanitas. Um maior número de medidas é aconselhável para a obtenção de uma precisão analítica aceitável. Em cristais de titanitas relativamente jovens (idades pós-neoproterozoicas), as idades 207Pb/206Pb são altamente imprecisas devido à elevada concentração de Pb comum; por outro lado, as idades 206Pb/238U apresentam valores bastante significativos. O desenvolvimento de análises em titanitas utilizando a técnica SHRIMP junto ao GEOLab-IGc-USP tem grande importância, principalmente quando acoplado a dados U-Pb obtidos em zircão e Ar-Ar em minerais, como anfibólio e biotita. Permite, além de um estudo geocronológico preciso, a obtenção de importantes parâmetros termocronológicos relacionados à ascensão/denudação de corpos rochosos
Microssonda Iônica de Alta Resolução e de Alta Sensibilidade (SHRIMP IIe/MC) do Instituto de Geociências da Universidade de São Paulo, Brasil: método analítico e primeiros resultados
This paper presents the characteristics of the high resolution secondary ion mass spectrometer coupled with an Ion Microprobe (SHRIMP IIe/MC), installed at the Institute of Geosciences of the University of São Paulo (IGc-USP), as well as the respective analytical procedures and the first results obtained with standard samples, making possible to conduct routine analysis of zircon samples. The standard of the Temora 2 zircon, with age of 416.78 Ma, was analyzed by the SHRIMP IIe/MC at the Institute of Geosciences of the University of São Paulo and yielded the age of 416.8 ± 3.8 Ma. Samples of the Archean zircon OG1 and the Neoproterozoic zircon Z6266, which yielded U-Pb ages of 3465.4 ± 0.6 Ma and of 559 ± 0.2 Ma, respectively, using Thermal Ionization Mass Spectrometry (TIMS), were analyzed by SHRIMP IIe/MC at the IG-USP and yielded U-Pb ages of 3462.6 ± 5.1 Ma and 561.0 ± 0.92 Ma, respectively, in Concordia diagrams. Therefore, these values and the literature values are very close. Both OG1 and Z6266 samples, due to the homogeneity in their composition and isotopic relationship, can be used as SHRIMP standard. These results indicate that data obtained using SHRIMP IIe at the IGc-USP are reliable and compatible with international standards. Dating of samples with ages ranging from Cenozoic to Archean, obtained using SHRIMP IIe/MC U-Pb geochronology on zircon crystals, is presented here to illustrate this point.Este trabalho apresenta as características de espectrômetro de massa de íons secundários acoplado com uma Microssonda Iônica de Alta Resolução, do tipo SHRIMP IIe/MC, instalada no Instituto de Geociências da Universidade de São Paulo (IGc-USP), bem como os respectivos procedimentos analíticos e os primeiros resultados obtidos em amostra de padrões, tornando-a apta a operar para análises em rotina de amostras de zircão. O padrão de zircão Temora 2, com idade de 416,78 Ma, foi analisado no SHRIMP IIe/MC de IGc-USP e apresentou a idade de 416,8 ± 3,8 Ma. As amostras de zircão arqueano OG1 e de zircão neoproterozoico Z6266, respectivamente com idades U-Pb obtidas por Espectrometria de Massa de Ionização Térmica (TIMS) de 3465,4 ± 0,6 Ma e de 559 ± 0,2 Ma foram analisadas no SHRIMP IIe de IG-USP e apresentaram idades U-Pb em diagramas Concórdia de 3462,6 ± 5,1 Ma e 561,0 ± 0,92 Ma respectivamente, portanto muito próximos aos valores referenciados na literatura. Tanto a amostra OG1 como a Z6266, em razão da homogeneidade de suas composições e das relações isotópicas, poderão ser utilizadas como padrões para SHRIMP. Esses resultados indicam que o SHRIMP IIe/MC do IGc-USP produz dados confiáveis compatíveis com os padrões internacionais. Como exemplos são aqui apresentadas datações de amostras de idades variáveis, desde cenozoica até arqueana, efetuadas pelo método geocronológico U-Pb por meio de SHRIMP IIe em cristais de zircão
Constrained spherical deconvolution provides evidence of extensive subcortical direct cerebellumbasal ganglia connections in human brain
Traditionally, the basal ganglia (BG) are thought to play a major role in the selection and inhibition of motor commands, while the cerebellum plays a role in tuning and reshaping on-going movement. In the past, the connections between the cerebellum and the cerebral cortex have been considered to be anatomically and functionally distinct from those linking the BG with the cerebral cortex. Evidences from recent anatomical experiments, using retrograde transneuronal transport of rabies virus in macaques, have challenged this old perspective demonstrating disynaptic subcortical pathways that directly link the cerebellum with the BG. Since the application of these techniques to the human brain remains elusive, due to the invasive nature of such methods, whether and to what extent these specific connections between the BG and cerebellum exist in the human brain remains unclear. However, recent developments in Diffusion Magnetic Resonance Imaging (dMRI) and diffusion tractography may allow for non-invasive and in vivo studies of the anatomical substrate of basal ganglia systems. Indeed, in our previous paper we studied the basal ganglia connectome providing strong evidences of a direct connection from cortex to Globus Pallidum (GPe and GPi) [1]. Thirteen normal subjects with no history of any overt neurological and/or psychiatric disorders were examined to test the hypotheses that substantial interactions, at least on the level shown in animal studies, also exist in the human brain. We demonstrated that it is feasible to disclose these cerebellar-subcortical connections by using constrained spherical deconvolution (CSD), an innovative approach which allows a reliable reconstruction of small- and long-fiber pathways, with subvoxel resolution in brain regions with multiple fiber orientations [2]. In particular we found evidences of subthalamic-cerebellar, dentate-thalamo-striatal, dentate-rubral-thalamic, dentate-rubral-pallidal and dentate-nigral connections. In addition to these connections, we found a direct cerebellar-dentate-pallidal connection never reported in literature to our knowledge; we identified and isolated two well-distinct tracts presenting an ipsilateral and contralateral component, converging mainly on the antero-medial part of the globus pallidus
Gender differences in chronic liver diseases in two cohorts of 2001 and 2014 in Italy
Background: Gender differences in chronic liver disease (CLD) have been partially investigated. To extend the present knowledge, we evaluated 12,263 patients with CLD enrolled in two national surveys (9997 in 2001 and 2557 in 2014). Methods: The two surveys prospectively recruited patients aged â¥Â 18 referring to Italian liver units throughout the country using a similar clinical approach and analytical methods. Results: The overall male to female ratio (M/F) was 1.4 (7138/5124). Compared with females, males were significantly more likely to be younger (52.9 vs. 58.7 yrs.), with HBV infection alone (13.2% vs. 9.2%) and with alcoholic liver disease alone (11.4% vs. 6.9%), but less likely to show HCV infection alone (48.0% vs. 67.9%). A male preponderance was observed in HBV-related cases (1.99) and in alcoholic-related cases (2.3), a preponderance observed both in the 2001 and in 2014 cases. In HCV-related cases, however, females predominated in 2001 (M/F 0.9) and males in 2014 (M/F 1.5).The rate of cirrhosis in alcohol-related etiology was close to 36% in both genders, a finding much higher than that observed for both sexes in HBV and HCV etiologies.Both males and females enrolled in 2014 were older (p < 0.001) and with a higher rate of cirrhosis and/or HCC (p < 0.001) than those investigated in 2001. There was a remarkable increase over time in the proportion of male abstainers (36.7% in 2001 and 64.3% in 2014). Conclusion: This study highlights important inter- and intra-gender differences in the characteristics and etiological factors of patients with CLD in Italy
Prospective validation of the CLIP score: a new prognostic system for patient with cirrhosis and hepatocellular carcinoma
Prognosis of patients with cirrhosis and hepatocellular carcinoma (HCC) depends on both residual liver function and tumor extension. The CLIP score includes Child-Pugh stage, tumor morphology and extension, serum alfa-fetoprotein (AFP) levels, and portal vein thrombosis. We externally validated the CLIP score and compared its discriminatory ability and predictive power with that of the Okuda staging system in 196 patients with cirrhosis and HCC prospectively enrolled in a randomized trial. No significant associations were found between the CLIP score and the age, sex, and pattern of viral infection. There was a strong correlation between the CLIP score and the Okuda stage, As of June 1999, 150 patients (76.5%) had died. Median survival time was 11 months, overall, and it was 36, 22, 9, 7, and 3 months for CLIP categories 0, 1, 2, 3, and 4 to 6, respectively. In multivariate analysis, the CLIP score had additional explanatory power above that of the Okuda stage. This was true for both patients treated with locoregional therapy or not. A quantitative estimation of 2-year survival predictive power showed that the CLIP score explained 37% of survival variability, compared with 21% explained by Okuda stage. In conclusion, the CLIP score, compared with the Okuda staging system, gives more accurate prognostic information, is statistically more efficient, and has a greater survival predictive power. It could be useful in treatment planning by improving baseline prognostic evaluation of patients with RCC, and could be used in prospective therapeutic trials as a stratification variable, reducing the variability of results owing to patient selection
RST-based methodology to enrich the design of digital storytelling
We present our results on the definition and validation of a methodology based on the Rhetorical Structure Theory to support authors of digital storytelling in the identification of contents from external repositories and their automatic mapping on different narrative structures. The methodology leverages on semantic models and technologies such as ontologies, clustering and text analysis, and supports the development of a smart environment for creation of stories starting from a set of pictures. We have validated our results in the context of the FIBAC project and for a specific narrative structure, i.e. The Dramatic Arc, for the creation of an educational storytelling related to the Second World War event
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