3,274 research outputs found

    Learning Bayesian Networks for Student Modeling

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    In the last decade, there has been a growing interest in using Bayesian Networks (BN) in the student modelling problem. This increased interest is probably due to the fact that BNs provide a sound methodology for this difficult task. In order to develop a Bayesian student model, it is necessary to define the structure (nodes and links) and the parameters. Usually the structure can be elicited with the help of human experts (teachers), but the difficulty of the problem of parameter specification is widely recognized in this and other domains. In the work presented here we have performed a set of experiments to compare the performance of two Bayesian Student Models, whose parameters have been specified by experts and learnt from data respectively. Results show that both models are able to provide reasonable estimations for knowledge variables in the student model, in spite of the small size of the dataset available for learning the parametersUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Análisis de los factores que determinan la imagen de España como destino turístico en los países lejanos culturalmente

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    Partiendo de la importancia que tiene la imagen en el proceso de elección de un destino turístico, así como en su satisfacción y lealtad, resulta fundamental comprender cuáles son los factores que influyen en la formación de la misma. En este contexto, esta investigación trata de desarrollar y validar empíricamente un modelo que explique los principales factores que la condicionan. En este caso, enmarcados en países lejanos culturalmente, países con un alto potencial de convertirse en emisores de gran importancia a nivel mundial, y, sin embargo, con un alto grado de desconocimiento. Se prevén implicaciones empresariales relevantes. En cuanto a la comunicación de los destinos, y sobre la base de los resultados, los responsables del destino deberán emprender un conjunto de acciones dirigidas mejorar y adecuar la imagen y adaptarla a las motivaciones de los turistas de países lejanos culturalmente.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Defects on a pyrite(100) surface produce chemical evolution of glycine under inert conditions : experimental and theoretical approaches

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    Acknowledgements This work has been supported by the MINECO project ESP2017-89053. The Instituto Nacional de Tecnica Aeroespacial supported the work performed at CAB. EER is thankful to Javier Martin-Torres, Alfonso Hernandez-Laguna and C. M. Pradier for their support and suggestions. This Project has been partially funded by the Spanish State Research Agency (AEI) Project No. MDM-2017-0737 Unidad de Excelencia ‘‘Marıa de Maeztu’’-Centro de Astrobiologıa (CSIC-INTA).Peer reviewedPublisher PD

    Mobile Usability: An Experiment to Check Whether Current Mobile Devices are Ready to Support Frames and iFrames

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    Frames have traditionally been identified as a usability issue in websites for computers. Literature points out that they may also be a problem for mobile websites but no studies have been carried out to prove it. Since mobile devices have changed a lot in recent years, it is necessary to check whether frames are still a problem for those devices. In this paper we have performed an experiment with twenty-two mobile devices, to test whether the content can be showed in their browsers, as well as their behavior with different configuration of frames and iframes and whether behavior of bookmarks and the back button is correct or not. The results show that frames and iframes should be avoided in mobile devices because they can cause many problems, which are explained in detail in this paper

    Role of bacterial community composition as a driver of the small-sized phytoplankton community structure in a productive coastal system

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    Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGWe present here the first detailed description of the seasonal patterns in bacterial community composition (BCC) in shelf waters off the Ría de Vigo (Spain), based on monthly samplings during 2 years. Moreover, we studied the relationship between bacterial and small-sized eukaryotic community composition to identify potential biotic interactions among components of these two communities. Bacterial operational taxonomic unit (OTU) richness and diversity systematically peaked in autumn–winter, likely related to low resource availability during this period. BCC showed seasonal and vertical patterns, with Rhodobacteraceae and Flavobacteriaceae families dominating in surface waters, and SAR11 clade dominating at the base of the photic zone (30 m depth). BCC variability was significantly explained by environmental variables (e.g., temperature of water, solar radiation, or dissolved organic matter). Interestingly, a strong and significant correlation was found between BCC and small-sized eukaryotic community composition (ECC), which suggests that biotic interactions may play a major role as structuring factors of the microbial plankton in this productive area. In addition, co-occurrence network analyses revealed strong and significant, mostly positive, associations between bacteria and small-sized phytoplankton. Positive associations likely result from mutualistic relationships (e.g., between Dinophyceae and Rhodobacteraceae), while some negative correlations suggest antagonistic interactions (e.g., between Pseudo-nitzchia sp. and SAR11). These results support the key role of biotic interactions as structuring factors of the small-sized eukaryotic community, mostly driven by positive associations between small-sized phytoplankton and bacteria.Xunta de Galicia | Ref. EM2013/023Xunta de Galicia | Ref. ED481A-2019/290Xunta de Galicia | Ref. ED431I 2020/03Ministerio de Economía y Competitividad | Ref. CTM2017-83362-RMinisterio de Ciencia e Innovación | Ref. PID2019-110011RB-C3

    Mobile Instant Messaging Apps: Usability Evaluation on iOS and Android Platforms and Recommendations for Developers

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    With the current growth in the use of smartphone devices, and the large amount of Mobile Instant Messaging applications available in the markets, this co-occurrence makes it highly valuable to evaluate the usability of this kind of applications in order to provide more satisfying user experiences. Within this paper, a systematic usability evaluation of Mobile Instant Messaging applications is presented, which will be applied to both iOS and Android platforms. Based on the results, it is suggested that this type of mobile applications present serious problems in performing tasks, poor user interfaces and lack of information about privacy and security features. Likewise, along with the results, this paper presents a list of usability recommendations to help developers improve their Instant Messaging applications

    Sex and gender disparities in patients with advanced gastroesophageal adenocarcinoma: data from the AGAMENON-SEOM registry

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    Gastroesophageal cancer; Gender; SexCáncer gastroesofágico; Género; SexoCàncer gastroesofàgic; Gènere; SexeBackground Recommendations for research articles include the use of the term sex when reporting biological factors and gender for identities or psychosocial or cultural factors. There is an increasing awareness of incorporating the effect of sex and gender on cancer outcomes. Thus, these types of analyses for advanced gastroesophageal adenocarcinoma are relevant. Patients and methods Patients with advanced gastroesophageal adenocarcinoma from the Spanish AGAMENON-SEOM registry treated with first-line combination chemotherapy were selected. Epidemiology, characteristics of the disease, treatment selection, and results were examined according to sex. Results This analysis included 3274 advanced gastroesophageal adenocarcinoma patients treated with combination chemotherapy between 2008 and 2021: 2313 (70.7%) men and 961 (29.3%) women. Tumors in females were more frequently HER2-negative (67.8% versus 60.8%; P < 0.0001), grade 3 (45.4% versus 36.8%; P < 0.001), diffuse (43.3% versus 26.5%; P < 0.0001), and signet ring cell histology (40.5 versus 23.9%; P < 0.0001). Peritoneal spread was more common in women (58.6% versus 38.9%; P < 0.0001), while liver burden was lower (58.9% versus 71.1%; P < 0.0001). There were no significant differences in treatment recommendation. Treatment doses, density, and duration were comparable between sexes. Women experienced more diarrhea (46% versus 37%; P < 0.0001), neutropenia (51% versus 43%; P < 0.0001), and anemia (62% versus 57%; P < 0.0001). After a median 59.6-month follow-up [95% confidence interval (CI) 54.5-70.8], there were no statistically significant differences between the sexes in progression-free survival [6.21 months (95% CI 5.8-6.5 months) versus 6.08 months (95% CI 5.8-6.3 months); log-rank test, χ2 = 0.1, 1 df, P = 0.8] or in overall survival [10.6 months (95% CI 9.8-11.1 months) versus 10.9 months (95% CI 10.4-11.4 months); log-rank test: χ2 = 0.6, 1 df, P = 0.5]. Conclusion This sex analysis of patients with advanced gastroesophageal adenocarcinoma from the AGAMENON-SEOM registry receiving first-line polychemotherapy found no differences in survival. Although women had worse prognostic histopathology, metastatic disease pattern, and greater toxicity, treatment allocation and compliance were equivalent

    Biological and clinical perspectives of the actionable gene fusions and amplifications involving tyrosine kinase receptors in lung cancer

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    MS is supported by a Juan-Rodés contract from the Instituto de Salud Carlos III (JR20/00015).This work was supported by Spanish grant from ICAPEM (ICAPEM becas 2021), to EP, and by Spanish grant form Asociación Española Contra el Cancer (AECC) (grant number GCB14142170MONT) to MSC. We thank M Rey providing language help and O Romero for data analysis support.Identifying molecular oncogenic drivers is crucial for precision oncology. Genetic rearrangements, including gene fusions and gene amplification, involving and activating receptor tyrosine kinases (RTKs) are recurrent in solid tumors, particularly in non-small cell lung cancer. Advances in the tools to detect these alterations have deepened our understanding of the underlying biology and tumor characteristics and have prompted the development of novel inhibitors targeting activated RTKs. Nowadays, druggable oncogenic rearrangements are found in around 15% of lung adenocarcinomas. However, taken separately, each of these alterations has a low prevalence, which poses a challenge to their diagnosis. The identification and characterization of novel targetable oncogenic rearrangements in lung cancer continue to expand, as shown by the recent discovery of the CLIP1-LTK fusion found in 0.4% of lung adenocarcinomas. While tyrosine kinase inhibitors that block the activity of RTKs have represented a breakthrough in the therapeutic landscape by improving the prognosis of this disease, prolonged treatment inevitably leads to the development of acquired resistance. Here, we review the oncogenic fusions and gene amplifications involving RTK in lung cancer. We address the genetic and molecular structure of oncogenic RTKs and the methods to diagnose them, emphasizing the role of next-generation sequencing technologies. Furthermore, we discuss the therapeutic implications of the different tyrosine kinase inhibitors, including the current clinical trials and the mechanisms responsible for acquired resistance. Finally, we provide an overview of the use of liquid biopsies to monitor the course of the disease

    Video Endoscopy for Laser Photoresection in Tracheobronchial Pathology: Some Considerations After 9 Years Experience With 2105 Treatments

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    Between 1984 and 1993 we performed 2105 laser treatments in 1210 patients: 52% of treatments were done for malignant pathology, 45% for benign tracheal stenoses and 3% were in a miscellaneous group. The procedure was carried out with a rigid bronchoscope under general anaesthesia. In patients with malignant tumors, it is a good palliative treatment—safe, well tolerated and with immediate results; it can be repeated as many times as needed with and is well accepted by the patient. In patients without tumors, this method avoids emergency tracheotomies. The long term results are now under evaluation

    Routine cerebrospinal fluid parameters as biomarkers in first-episode psychosis: A prospective observational study

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    In recent years, multiple studies have investigated the role of biomarkers in first-episode psychosis (FEP) to facilitate early diagnosis, disease stratification, therapeutic choice and outcome prediction. Few studies have focused on cerebrospinal fluid (CSF) investigations. In this prospective observational study, 95 FEP inpatients were followed up for one year. A lumbar puncture was performed at index admission (baseline) to study the CSF parameters (glucose, total proteins, lactate dehydrogenase [LDH], and pleocytosis). At the baseline visit, the clinical assessment included prodromal (psychotic and non-psychotic) symptoms before the psychotic outbreak and psychopathology at admission. The SCID-I was administered to obtain a clinical diagnosis at baseline and at 12 months. The relationship between prodromal and psychopathology symptoms at the baseline visit was tested with multiple linear regression. Multinomial logistic regression was also used to explore the association between CSF biomarkers and longitudinal diagnoses at follow-up (schizophrenia/schizoaffective disorder vs unipolar/bipolar depression vs other psychoses). Higher CSF glucose was associated with depressive (Standardized beta = 0.27, p = 0.041) and disorganized/concrete symptoms (Standardized beta = 0.33, p = 0.023) and lower CSF LDH was associated with prodromal symptoms (Standardized beta = −0.25, p = 0.042). Lower LDH concentrations were also associated with social withdrawal (r = −0.342, p = 0.001). CSF glucose was a predictor of the long-term diagnosis (lower CSF concentrations were associated with schizophrenia or schizoaffective disorder diagnoses [OR = 0.88, CI95%: 0.77–0.99). Our study suggests that CSF biomarkers that involve bioenergetic systems are associated with prodromal symptoms and the phenotype of psychotic disorders during the early stages of the disease
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