Querying Geometric Figures Using a Controlled Language, Ontological Graphs and Dependency Lattices

Dynamic geometry systems (DGS) have become basic tools in many areas of geometry as, for example, in education. Geometry Automated Theorem Provers (GATP) are an active area of research and are considered as being basic tools in future enhanced educational software as well as in a next generation of mechanized mathematics assistants. Recently emerged Web repositories of geometric knowledge, like TGTP and Intergeo, are an attempt to make the already vast data set of geometric knowledge widely available. Considering the large amount of geometric information already available, we face the need of a query mechanism for descriptions of geometric constructions. In this paper we discuss two approaches for describing geometric figures (declarative and procedural), and present algorithms for querying geometric figures in declaratively and procedurally described corpora, by using a DGS or a dedicated controlled natural language for queries.Comment: 14 pages, 5 figures, accepted at CICM 201

Integrating DGSs and GATPs in an Adaptative and Collaborative Blended-Learning Web-Environment

The area of geometry with its very strong and appealing visual contents and its also strong and appealing connection between the visual content and its formal specification, is an area where computational tools can enhance, in a significant way, the learning environments. The dynamic geometry software systems (DGSs) can be used to explore the visual contents of geometry. This already mature tools allows an easy construction of geometric figures build from free objects and elementary constructions. The geometric automated theorem provers (GATPs) allows formal deductive reasoning about geometric constructions, extending the reasoning via concrete instances in a given model to formal deductive reasoning in a geometric theory. An adaptative and collaborative blended-learning environment where the DGS and GATP features could be fully explored would be, in our opinion a very rich and challenging learning environment for teachers and students. In this text we will describe the Web Geometry Laboratory a Web environment incorporating a DGS and a repository of geometric problems, that can be used in a synchronous and asynchronous fashion and with some adaptative and collaborative features. As future work we want to enhance the adaptative and collaborative aspects of the environment and also to incorporate a GATP, constructing a dynamic and individualised learning environment for geometry.Comment: In Proceedings THedu'11, arXiv:1202.453

Development of Non-Linear Equations for Predicting Electrical Conductivity in Silicates

Electrical conductivity is of fundamental importance in electric arc furnaces (EAF) and the interaction of this phenomenon with the process slag results in energy losses and low optimization. As mathematical modeling helps in understanding the behavior of phenomena and it was used to predict the electrical conductivity of EAF slags through artificial neural networks. The best artificial neural network had 100 neurons in the hidden layer, with 6 predictor variables and the predicted variable, electrical conductivity. Mean absolute error and standard deviation of absolute error were calculated, and sensitivity analysis was performed to correlate the effect of each predictor variable with the predicted variable.Comment: 8 pages, 6 figures, 1 table (AISTech 2023 - Presented and Accepted

The technical challenge of Functional 18F-FDG-PET Brain imaging in paediatric epilepsy

Epilepsy is a chronic brain disease, characterized by the appearance of crisis (whit or without convulsions), caused by abnormal electric activity on brain cells. Neuroimaging might be necessary in the work-up of epilepsy for localisation of the seizure focus for possible surgical cure. In our department, we started performing inter-ictal 18F-2-deoxyglucose (FDG)-PET/TC Brain imaging in 2009, in paediatric patients, following EANM procedure guidelines. Aim: the aim of the study was to retrospectively review all the performed inter-ictal 18F-FDG-PET/TC brain imaging, to assess the difficulties found during these procedures and the deviation according to guideline recommendations. We also intend to focus on the major importance of an optimal cooperation with other departments, such as anaesthesiology and neurophysiology. Material and Methods: between 2009 and 2012, eleven patients (pt) were referred for an 18F-FDG-PET-TC brain study, with ages between 10 months - 18 years old all with medically intractable epilepsy. The exams were performed with different conditions according to the needs of each patient, because we know that exceptional procedures call for special conditions. Results: All files were review for pt information pertinent to performance of the procedure, pt pre-arrival preparation, pt pre-injection preparation, pt monitoring for ictal crises before injection (EEG), pt sedation, variability of radiopharmaceutical administration and data acquisition parameters. 8 of the pt were performed with anaesthesia while 3 without since the pediatric patient were cooperative. All of the pt were monitored under parental surveillance, one with additional movie recording and other with EEG. Conclusion: We found that this process of retrospective review of this pool of paediatric patients with epilepsy enhanced the learning curve in this very specific procedure. We also found it critical to request the collaboration of the departments of anaesthesiology and neurophysiology

Linear Modeling of the Glass Transition Temperature of the system SiO2-Na2O-CaO

This work aimed to mathematically model the glass transition temperature (Tg), one of the most important parameters regarding the behavior of slag, responsible for the sudden change in thermomechanical properties of non-crystalline materials, by the chemical composition of the SiO2-Na2O-CaO system, widely applicable in the production of glasses and constituent of iron, magnesium and aluminum metallurgy slags. The SciGlass database was used to provide data for mathematical modeling through the Python programming language, using the method of least squares. A new equation was established, called P Model, and it presented a lower mean absolute error and lower standard deviation of absolute errors in relation to 3 equations in the literature. The raised equation provides significant results in the mathematical modeling of Tg by the chemical system SiO2-Na2O-CaO, valid for the limits of the data used in the mathematical modeling.Comment: 5 pages, 3 figures, 2 table

Liquidus temperature nonlinear modeling of silicates SiO2−R2O−ROSiO_2-R_2O-RO

The liquidus temperature is an important parameter in understanding the crystalline behavior of materials and in the operation of blast furnaces. Its modeling can be carried out by linear and nonlinear methods through data, considering the artificial neural network a modeling method with high efficiency because it presents the theorem of universal approximation and with that better performances and possibility of greater oscillations. The best linear model and the best nonlinear model were modeled by structural parameters and presented a good numerical approximation, thus demonstrating that mathematical modeling can be performed using structural arguments and also showing a dimensionality reduction method for modeling a thermophysical property of the materials.Comment: 11 pages, 8 figures, 3 table

Geographical variation in cancer survival in England, 1991–2006: an analysis by Cancer Network

BACKGROUND: Reducing geographical inequalities in cancer survival in England was a key aim of the Calman-Hine Report (1995) and the NHS Cancer Plan (2000). This study assesses whether geographical inequalities changed following these policy developments by analysing the trend in 1-year relative survival in the 28 cancer networks of England. METHODS: Population-based age-standardised relative survival at 1 year is estimated for 1.4 million patients diagnosed with cancer of the oesophagus, stomach, colon, lung, breast (women) or cervix in England during 1991-2006 and followed up to 2007. Regional and deprivation-specific life tables are built to adjust survival estimates for differences in background mortality. Analysis is divided into three calendar periods: 1991-5, 1996-2000 and 2001-6. Funnel plots are used to assess geographical variation in survival over time. RESULTS: One-year relative survival improved for all cancers except cervical cancer. There was a wide geographical variation in survival with generally lower estimates in northern England. This north-south divide became less marked over time, although the overall number of cancer networks that were lower outliers compared with the England value remained stable. Breast cancer was the only cancer for which there was a marked reduction in geographical inequality in survival over time. CONCLUSION: Policy changes over the past two decades coincided with improved relative survival, without an increase in geographical variation. The north-south divide in relative survival became less pronounced over time but geographical inequalities persist. The reduction in geographical inequality in breast cancer survival may be followed by a similar trend for other cancers, provided government recommendations are implemented similarly

Adjusting for overdispersion in piecewise exponential regression models to estimate excess mortality rate in population-based research.

BACKGROUND: In population-based cancer research, piecewise exponential regression models are used to derive adjusted estimates of excess mortality due to cancer using the Poisson generalized linear modelling framework. However, the assumption that the conditional mean and variance of the rate parameter given the set of covariates x i are equal is strong and may fail to account for overdispersion given the variability of the rate parameter (the variance exceeds the mean). Using an empirical example, we aimed to describe simple methods to test and correct for overdispersion. METHODS: We used a regression-based score test for overdispersion under the relative survival framework and proposed different approaches to correct for overdispersion including a quasi-likelihood, robust standard errors estimation, negative binomial regression and flexible piecewise modelling. RESULTS: All piecewise exponential regression models showed the presence of significant inherent overdispersion (p-value <0.001). However, the flexible piecewise exponential model showed the smallest overdispersion parameter (3.2 versus 21.3) for non-flexible piecewise exponential models. CONCLUSION: We showed that there were no major differences between methods. However, using a flexible piecewise regression modelling, with either a quasi-likelihood or robust standard errors, was the best approach as it deals with both, overdispersion due to model misspecification and true or inherent overdispersion

Effect of immunocastration and caponization on fatty acid composition of male chicken meat

Research Areas: AgricultureAiticle in International JournalABSTRACT - Recently, immunocastration with Improvac (ImmC). has been tested in broilers and a considerable reduction in serum testosterone concentration (reduced by 79% compared to roosters) was observed. The aim of this study was to evaluate the effect of immunocastration on meat fatty acid (FA) composition and its comparison with caponized and intact males (roosters). The study was conducted with 3 experimental groups: control group (roosters), the group of birds submitted to surgical caponization (SurgC), and the group of birds submitted to immunocastration with Improvac. The comparison of breast meat partial FA sums of castrated (SurgC and ImmC) with control birds (roosters) revealed that castrated birds showed significantly higher content of n-3 polyunsaturated fatty acids (n-3 PUFA) than control birds (1.76 vs. 1.46 g/100 g of total FA; superiority of 20.2%), which has contributed to the occurrence of significant differences on both the n-6/n-3 ratio and the atherogenicity index (AI). In contrast, on leg meat portion, castrated birds displayed higher contents of both total saturated and monounsaturated fatty acids (SFA and MUFA, with 2.2 and 4.1% more, respectively) and lower total n-6 PUFA content (8.3% less) than was observed in control birds, which contributed to significant differences in the AI index. On the other hand, the comparison of breast meat portion from SurgC with ImmC showed that immunocastration contributed to lower total SFA and higher total n-6 PUFA, which have contributed to significant differences on both Polyunsaturated/Saturated (P/S) and n-6/n-3 ratios. Whereas, on leg meat portion no significant differences were observed on partial sums and a single difference was observed on the thrombogenicity index. Immunocastration of broilers has contributed to minor changes in the FA profile, but has improved the overall lipid quality indexes in both breast and leg meat portions. Therefore, immunocastration could be applied as an alternative method to caponization without negative consequences in meat FA profile.info:eu-repo/semantics/publishedVersio