551 research outputs found

    A comparison of procedures for structural learning of biological networks

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    Over the past years, microarray technologies have produced a tremendous amount of gene expression data. The availability of these data has motivated researchers to assess genes function and to gain a deeper understanding of the cellular processes, using network theory as tool for the analysis. An elegant framework for modeling and inferring network structures in biological systems is provided by graphical models. They allow the stochastic description of network associations and dependence structures in complex highly structured data. However, typically gene expression data set includes a large number of variables but only few samples making standard graphical model theories inapplicable. The issues presented by genetic data have led to further extend the theory of graphical models to allow their applications in this area. The main aim of this thesis is the comparison of recent procedures, which estimate sparse concentration matrices and learn the structure of biological networks, through the use of both simulated and real data. The compared procedures are: G-Lasso algorithm (Friedman et al., 2008), Shrinkage estimator with empirical Bayes approach for model selection (Schafer and Strimmer, 2005a, 2005b), PC-algorithm (Kalisch and Buhlmann, 2007). When n > p, we consider also the simple frequentist approach based on MLE and t-test for model selection (see Lauritzen, 1996). Regarding the simulated data, for having a realistic simulation of the biological structures, the data have the peculiarity to reproduce few gene regulatory network structures of interest and they are generated by exploiting some properties of the Cholesky decomposition of a matrix. Concerning the real data, we consider the analysis of one of the best characterized system: Escherichia coli. A large part of its transcriptional regulatory network is known, hence it can be used as a gold-standard to assess the performance of different procedures in the comparative study.Negli ultimi anni, le tecnologie dei microarray hanno prodotto una grande quantità di dati provenienti da processi di espressione genica. La disponibilità di questi dati ha permesso ai ricercatori di poter approfondire lo studio della funzione dei diversi geni e poter acquisire una più profonda conoscenza sui processi cellulari, utilizzando come strumento di ricerca la teoria dei network. I modelli grafici risultano essere un utile strumento per la modellazione e l'analisi delle strutture dei networks derivanti da dati biologici. Infatti, questi modelli consentono di rappresentare in modo stocastico le associazioni e le strutture di dipendenza tra gli elementi di data set con struttura complessa. Tuttavia, i dati derivanti da profili di espressione genica si presentano con un elevato numero di variabili ma solo poche osservazioni rendendo, perciò, la teoria classica dei modelli grafici inapplicabile. I problemi legati all'utilizzo di dati genetici hanno portato ad estendere la teoria dei modelli grafici per consentire l'impiego di questi modelli anche in questo campo di applicazione. Lo scopo principale di questa tesi è quello di confrontare, attraverso l'utilizzo di dati simulati e reali, recenti procedure sviluppate con lo scopo di stimare matrici di concentazione sparse e ricostruire i networks biologici. Le procedure considerate per il confronto sono: l'algoritmo G-Lasso (Friedman et al., 2008), lo stimatore Shrinkage associato con l'approccio Bayes empirico per la selezione del modello (Schafer and Strimmer, 2005a, 2005b), l'algoritmo PC (Kalisch and Buhlmann, 2007). Quando n > p, consideriamo anche un semplice approccio frequentista basato sullo stimatore ML e l'utilizzo del test t per la selezione del modello (si veda Lauritzen, 1996). Per quanto riguarda i dati simulati, per avere strutture biologiche simili a quelle reali, i dati hanno la peculiarità di riprodurre alcune strutture dei network di regolazione genica e sono ottenuti sfruttando alcune proprieta’ della decomposizione di Cholesky di una matrice. Per il confronto con dati reali, sono stati utilizzati dati derivanti da uno dei sistemi maggiormente studiati: Escherichia coli. Infatti, grand parte del network di regolazione genica di questo battere è noto, quindi può essere utilizzato come riferimento per valutare il rendimento delle diverse procedure poste a confronto

    Larvicidal activity and influence of bacillus thuringiensis Var. israelensis on aedes albopictus oviposition in ovitraps during a two-week check interval protocol

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    Toxicity persistence of Bacillus thuringiensis var. israelensis (Bti) was evaluated in laboratory and field trials to develop a new protocol for Aedes albopictus monitoring. In the laboratory, the residual toxicity of 5 Bti formulations was compared using the percentage mortality at days 4, 8, 12, and 16 of Culex pipiens larvae exposed for 24 h to Bti treatments. The results showed a good performance of all tested formulations (>97 mortality at day 14, for all the formulations), but only VectobacTM 12AS at the concentration of 1 ml/liter showed an efficacy of 100 for 2 wk. A field study was designed to test the effect of Bti on the ovitrap check interval or influence of ovipositional response of gravid Ae. albopictus females. Three different ovitrap treatments were used: ovitraps with tap water checked weekly; ovitraps with tap water checked every 2 wk; ovitraps with Bti (Vectobac 12AS, dose of 1 ml/liter) checked every 2 wk. Our study demonstrated that in the ovitrap, the toxic action of a 1 solution of Bti was maintained for at least 14 days with mortality of 100 and that rainfall did not seem to negatively influence the residual action of Bti. Therefore the probability that the larvae may complete the developmental cycle in ovitraps with Bti seems to be very low. The oviposition activity index showed that Bti enhances the oviposition rate of Ae. albopictus by 17.4. © 2009 by The American Mosquito Control Association, Inc

    Apresentação

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    Como citar: TARTUCE, Gisela Lobo; ALMEIDA, Patrícia Albieri. Apresentação. In: FUNDAÇÃO CARLOS CHAGAS. Prêmio Professor Rubens Murillo Marques 2023: experiências docentes em licenciaturas. São Paulo: FCC, 2023. p. 7-8. (Textos FCC: Relatórios técnicos, 65). Tartuce, G. L., & Almeida, P. A. (2023). Apresentação. In Fundação Carlos Chagas, Prêmio Professor Rubens Murillo Marques 2023: Experiências docentes em licenciaturas (Textos FCC: Relatórios técnicos, 65, pp. 1-8). FCC

    Control device for a refrigerating machine

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    The present invention concerns a control device for a refrigerating machine according to claim 1. In particular, the present invention finds useful, but not exclusive, application in the regulation of the delivery temperature of a service fluid in output from a water chiller for centralized air-conditioning systems, to which the following description shall make explicit reference without, however, any loss of generality

    Positive Narrative Therapy for an Unspecified Eating Disorder: A Child Case Report

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    A new sequential multicomponent treatment (cognitive behavioral therapy followed by well-being-enhancing narrative strategies) was applied for an unspecified eating disorder in a 10-year-old boy for reducing symptoms and improving well-being. Both distress and well-being were assessed with self and observer ratings at baseline, posttreatment, and 3-, 6-, 12-month follow-up. An ABA design was used and reliable change indexes were calculated as outcome measures. This new sequential psychotherapeutic approach, which integrated standard cognitive behavioral therapy with narrative strategies addressed at promoting well-being in a child patient diagnosed with an unspecified eating disorder, was able to reduce symptoms and to foster his resources and positive behaviors. The patient himself, his parents, and teachers confirmed these improvements. This case report shows the clinical usefulness of a new sequential psychotherapeutic approach for treating an unspecified eating disorder in a child. It provides psychotherapists with relevant clinical implications concerning the emotional and interpersonal dimensions involved in this disabling condition

    Once upon a time: A school positive narrative intervention for promoting well-being and creativity in elementary school children

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    Recent research highlighted the importance of incorporating programs for promoting well-being and creativity in schools. However, eudaimonic well-being received only limited attention and only few interventions aimed at its promotion in the school setting. This research aimed to compare the efficacy of an intervention based on storytelling and narrative techniques versus a control condition for the promotion of well-being and creativity in elementary schoolchildren. A total of 165 students (78 girls, 87 boys; Mage = 9.3 years; SD = 0.5) were randomized to a School Positive Narrative Intervention or to a controlled condition. Children were assessed before and after intervention and at 3-month follow-up with self-reports of well-being, anxiety, depression and somatization. A storytelling task was implemented, and specific creativity storytelling scores were calculated for the stories produced by children during the intervention. At post intervention, children assigned to the narrative intervention reported increased levels of well-being and decreased depression, anxiety, and somatization, compared to controls. These improvements were maintained at 3-month follow-up. Higher scores on creativity emerged in stories focused on fear, sadness, and happiness. The use of narrative strategies help children to identify their personal resources, to express creativity, and to assimilate the concept of eudaimonic well-being that could be difficult to process because of its abstractness and multidimensional nature. This brief intervention fostered children creativity and it produced beneficial effects on children's well-being and distress

    Creatività e benessere eudaimonico nelle scuole primarie | Eudaimonic creativity and well-being in elementary schools

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    L’importanza d’incorporare programmi psicoeducativi per promuovere il benessere e la creatività nelle scuole è ampiamente documentata. Questa ricerca ha confrontato l’efficacia di un intervento scolastico narrativo (storytelling) rispetto a una condizione di controllo. L’intervento scolastico (quattro incontri settimanali) consisteva nella lettura e creazione di fiabe con uno specifico contenuto emotivo, coinvolgendo 165 studenti di scuola primaria. Al post-intervento, i bambini hanno riportato un aumento nei livelli di benessere e una diminuzione della depressione, dell’ansia e della somatizzazione. Maggiore creatività è emersa nelle storie incentrate sulla paura, la tristezza e la felicità. L’uso di strategie narrative aiuta i bambini a identificare le proprie risorse personali, ad esprimere la creatività e a migliorare il benessere.The importance of incorporating psycho-educational programs to promote well-being and creativity in schools is well documented. This research compared the effectiveness of a school storytelling intervention against a control condition. The school intervention (four weekly meetings) consisted in the reading and creation of fairy tales with a specific emotional content, involving 165 primary school students. At post-intervention, children reported an increase in well-being levels and a decrease in depression, anxiety and somatization. More creativity emerged in the stories centered around fear, sadness and happiness. Using narrative strategies helps children identify their personal assets, express creativity and improve well-being

    Well-Being Therapy: State of the Art and Clinical Exemplifications

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    A specific psychotherapeutic strategy for increasing psychological well-being, well-being therapy (WBT), has been developed almost two decades ago, and tested in a number of randomized controlled trials over these years. WBT is described in its current clinical features, with two clinical case presentations (one involving a depressed woman and one involving a child with ADHD) that illustrate its additive value in combination with cognitive behavioral treatment or pharmacotherapy. Recent developments with children and adolescents, both in school and clinical settings, are also reported. These contributions underline the peculiarities of this approach: it is aimed at promoting well-being, but differentiates form other positive interventions since it adopts a wider eudaimonic perspective. Thus, WBT takes into consideration both psychological well-being and distress in determining patient’s clinical outcomes. Limitations of current research on WBT and future developments as a preventive strategy for vulnerable individuals are discussed. © 2014, Springer Science+Business Media New York
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