GME versus OLS - Which is the best to estimate utility functions?

This paper estimates von Neumann andMorgenstern utility functions comparing the generalized maximum entropy (GME) with OLS, using data obtained by utility elicitation methods. Thus, it provides a comparison of the performance of the two estimators in a real data small sample setup. The results confirm the ones obtained for small samples through Monte Carlo simulations. The difference between the two estimators is small and it decreases as the width of the parameter support vector increases. Moreover the GME estimator is more precise than the OLS one. Overall the results suggest that GME is an interesting alternative to OLS in the estimation of utility functions when data is generated by utility elicitation methods.Generalized maximum entropy; Maximum entropy principle; von Neumann and Morgenstern utility; Utility elicitation.

VCAM1 modulation on endothelial cells – implications for vasculopathy in sickle cell anemia

Sickle cell anemia (SCA) is a highly heterogeneous and multifactorial-like monogenic disease that arises from homozygosity for the c.20A>T mutation in the HBB gene. Vascular disease is systemic in SCA, with profound effects in organs like the brain, where stroke is the most severe end of the cerebral vasculopathy (CVA) spectrum. Endothelial dysfunction plays a major role in vasculopathy with several adhesion molecules, such as VCAM1, being produced by the endothelium altered as a response to inflammatory cytokine (e.g., TNF-α) signalling. In previous association studies, we found positive associations between the presence of four specific VCAM1 gene promoter haplotypes and i) high blood flow velocities in the median cerebral artery, and ii) a chronic hemolysis biochemical marker. In this study, we aimed to assess the functional role of those VCAM1 promoter haplotypes in endothelial cell response following endothelial activation through TNF-α stimulation. After molecular cloning of 3 haplotype constructs, using a pGL4 promoterless vector, haplotype sequence was confirmed, by Sanger sequencing, prior to transfection. We used EAhy926, HUVEC and HBEC as different endothelial cell models, and performed transfection experiments for each construct, with and without TNF-α stimulation. Differences in promoter activity were assessed by luciferase reporter assay. All haplotypes showed differences in promoter activity, after TNF-α stimulation, in all cell models. Haplotype 1 showed decreased promoter activity, while haplotypes 7 and 8 showed increased activity after TNF-α stimulation, in all cell models. These results are consistent with lower VCAM1 expression due to haplotype 1, and therefore a protective effect. Conversely, a higher expression due to haplotypes 7 and 8, suggests an increased vasculopathy risk, in a pro-inflammatory milieu. The association between specific haplotypes and endothelial cell response further enhances the modifier effect of VCAM1 on endothelial dysfunction and its impact in SCA pathophysiology, as well as its potential role as a biomarker of SCA vasculopathy risk, severity and prognosis.This work was partially supported by INSA_202DGH720 project.info:eu-repo/semantics/publishedVersio

Importância da mutação JAK2 V617F nas doenças mieloproliferativas clássicas

Mestrado em Biologia Molecular e CelularOs Síndromes Mieloproliferativos (SMP) são um grupo de doenças heterogéneas nas quais se verifica uma produção excessiva de células sanguíneas pelos precursores hematopoieticos. A Policitémia Vera (PV), a Trobocittémia Essencial (TE), a Mielofibrose Idiopática (MF) e a Leucemia Mielóide Crónica (LMC) são conseideradas SMP clássicas que apresentam características clínicas e biológicas comuns. Ao contrário da LMC, cuja etiologia está relacionada com a proteína constitutivamente activa BCR-ABL, o mecanismo molecular da PV, TE e MF permaneceu por muito tempo desconhecido. O grande número de estudos respeitantes ás SMP resultou em 2005 na descrição de uma mutação pontual no exão 14 do gene Janus Kinase 2 (JAK2), denominada JAK2 V617F, recorrente em pacientes com SMP clássicas BCR-ABL negativos. Esta mutação leva à activação constitutiva da proteína JAK2. Estudos recentes revelam que a mutação JAK2 V617F está presente em 83-95% de doentes com PV, 50 a 70% de doentes com TE e em cerca de 50% de doentes com MF. Os objectivos deste estudo consistem em determinar a frequência da mutação JAK2 V617F numa população de doentes dos HUC-EPE com diagnóstico de PV, TE e MF, comparar a frequência obtida com a literatura, avaliando deste modo a eficácia da metodologia usada e demonstrar que esta mutação é estatísticamente significativa nos SMP clássicos Ph-. O estudo incidiu sobre um grupo de 475 doentes aos quais foi solicitada a análise da mutação JAK2 V617F no periodo decorrente de Junho de 2006 e Maio de 2010. A metodologia usada consistiu na extracção de ADN genómico, seguida de uma reacção de PCR utilizando primers que permitiram a amplificação dos alelos normal e mutado, e sua subsequente identificação através de uma electroforese com posterior coloração utilizando nitrato de prata. Posterior análise dos resultados determinou uma frequência da mutação JAK2 V617F de 74%, 66% e 42% em pacientes com PV, TE e MF respectivamente. Utilizando o teste Qui-Quadrado de Pearson foi possivel demonstrar que: existe uma associação entre a mutação e o sexo feminino nos doentes com PV; relacionando a mutação com a doença verificou-se que a heterozigotia tem uma forte associação com a TE enquanto que a homozigotia tem associação com a PV. Por fim estabeleceu-se uma forte associação desta mutação com as SMP Ph-, ou seja, para α= 0,05 foi obtido P<0,001. Para provar estatísticamente a eficácia da metodologia usada efectuou-se o teste Qui-Quadrado de Aderência no qual X2(observado)= 4,69, inferior ao X2 (crítco)= 5,99. Este resultado é extremamente relevante pois determina que não existe necessidade de implementar outra técnica, que seria bastante mais dispendiosa, e no presente não seria vantajosa. Futuramente quando a terapía passar pelo uso de proteínas inibidoras de JAK2, será necessário efectuar um estudo semelhante para averiguar se a metologia qualitativa usada é suficiente para fazer a monitorização terapêutica.The Myeloproliferative Syndromes are a heterogeneous group of diseases in which there was an overproduction of blood cells by hematopoietic precursors. Polycythemia Vera (PV), the Essential Trobocittémia (TE), Idiopathic Myelofibrosis (MF) and Chronic Myelogenous Leukemia (CML) are classic SMP that have in common clinical and biological characteristics. Unlike the LMC, whose etiology is associated with the protein constitutively active BCR-ABL, the molecular mechanism of PV, ET and IM long still remain unknown. The large number of studies relating to SMP led in 2005, to the description of a point mutation in exon 14 of gene Janus Kinase 2 (JAK2), known as JAK2 V617F, in patients with recurrent classic SMP Ph-. This mutation leads to constitutive activation of JAK2 protein. Recent studies shown that JAK2 V617F is present in 83-95% of patients with PV, 50 to 70% of ET patients and in 50% of patients with IM. The objectives of this study were to determine the frequency of JAK2 V617F in a patient population of HUC-EPE diagnosed with PV, ET and MF, comparing the frequency obtained with the literature, thereby assessing the effectiveness of the methodology used. The study focused on a group of 475 patients who were asked to JAK2 V617F mutation analysis in the period from June 2006 to May 2010. The methodology used consisted in a extraction of genomic DNA, followed by a PCR reaction using primers that allowed the amplification of normal and mutated alleles, and their subsequent identification by an electrophoresis and staining using silver nitrate. Further analysis of the results determined a frequency of JAK2 V617F in 74%, 66% and 42% in patients with PV, ET and IM respectively. Using the Pearson chi-square test was possible to demonstrate that: the mutation has an association with female gender in PV patients, observing the relationship between the disease and the mutation was found that heterozygosity has a strong association with TE whereas homozygosity is associated with the PV. Finally we established a strong association of this mutation with Ph-SMP, to α= 0.05 was obtained a P<0,001. To statistically prove the effectiveness of the methodology was carried out a Chi-square test where X2 (observed) = 4.69 was lower than the X2 (insidious) = 5.99. This result is extremely important because it determines that there was no need to implement a quantitative technique, it would be far more expensive, and this would not be advantageous. In the future when therapy over the use of protein inhibitors of JAK2, we must perform a similar study to see whether the qualitative methodology used is enough to make the therapeutic monitorization

Escalas psicométricas e propriedade escalar na percepção de velocidade em pombos

Dissertação de mestrado integrado em Psicologia (área de especialização em Psicologia Experimental e suas Aplicações)O presente estudo enquadra-se na área de investigação da percepção de velocidade. Usando uma tarefa de discriminação simultânea, em que os estímulos eram apresentados num paradigma de escolha forçada com duas alternativas, estudaram-se as escalas psicométricas e a propriedade escalar na percepção de velocidade em quatro pombos. Na primeira experiência, os sujeitos foram treinados a discriminar duas velocidades, 0.2cm/seg vs. 5cm/seg. Numa fase de teste, apresentaram-se aos pombos pares de estímulos, em que um dos estímulos movia-se sempre a 5cm/seg e o outro movia-se a uma velocidade intermédia às velocidades de treino, de modo a obter uma função psicométrica. As funções psicométricas obtidas revelaram pontos de bissecção que vão de encontro aos resultados obtidos em estudos anteriores. Na segunda experiência, usando as mesmas velocidades que na discriminação da experiência 1 mas apresentando estímulos diferentes, estudámos a escala da velocidade e testámos as previsões dos modelos linear e logarítmico. Os dados obtidos indicam que a velocidade é representada linearmente. Na terceira experiência, usando velocidades com o dobro do valor das usadas nas experiências anteriores, comparámos as funções psicométricas obtidas nas experiências 2 e 3 de modo a testar se a percepção de velocidade em pombos obedece à propriedade escalar. As análises conduzidas sugerem que a propriedade escalar não se aplica à percepção de velocidade em pombos. No entanto, conclui-se que os valores de velocidade usados poderão ser demasiado altos e que, para se poderem tirar conclusões mais sólidas, um estudo com valores de velocidade inferiores seria necessário.The present study is concerned with the perception of velocity by pigeons. Using a simultaneous discrimination task, where stimuli were presented in a two-alternative forced choice paradigm, we studied the psychometric scales as well as the scalar property of velocity perception in four pigeons. In the first experiment, the subjects learned to discriminate two velocities, 0.2cm/sec vs. 5cm/sec. In a test phase, the pigeons were presented with pairs of stimuli in which one of the stimuli was always moving at 5cm/sec, and the other one at an intermediate velocity between the training velocities, in order to obtain a psychometric function. The psychometric functions obtained revealed bisection points at values consistent with previous studies. In a second experiment, using the same velocities used for the experiment 1 but presenting different stimuli, we studied the velocity scale and tested the predictions of linear and logarithmic models. The data obtained revealed that velocity is encoded linearly. In the third experiment, using velocities twice as big as the ones used in the other two experiments, we compared the psychometric functions obtained for experiments 2 and 3 in order to test if velocity perception obeys the scalar property. The analysis suggests that the scalar property does not apply to velocity perception in pigeons. However, we concluded that the velocity range used may have been too high. In order to draw stronger conclusions, a study using lower velocities should be conducted

Estimating utility functions using generalized maximum entropy

This paper estimates von Neumann and Morgenstern utility functions using the generalized maximum entropy (GME), applied to data obtained by utility elicitation methods. Given the statistical advantages of this approach, we provide a comparison of the performance of the GME estimator with ordinary least square (OLS) in a real data small sample setup. The results confirm the ones obtained for small samples through Monte Carlo simulations. The difference between the two estimators is small and it decreases as the width of the parameter support vector increases. Moreover, the GME estimator is more precise than the OLS one. Overall, the results suggest that GME is an interesting alternative to OLS in the estimation of utility functions when data are generated by utility elicitation methods

Study of catalytic processes for biodiesel production wastewater treatment

The study of the possibility of removing organic compounds from wastewater originating from the biodiesel purifi cation stage by two catalytic processes, HSO5 - /transition metal and Fenton method has been presented. The source of the ion HSO5 - is potassium monopersulphate (2KHSO5 ∙KHSO4 ∙K2SO4) (Oxone) that may be decomposed into radicals (OH., SO4-., SO5-.) by means of transition metal as Co(II). Different concentrations were used for both compounds and the combination ([Co2+] = 1.00μM/[HSO5 -] = 5.00·10-2 M) achieved the highest COD removal (60%) and complete decomposition of the oxidant was verifi ed for contact times of 45 min. This process has some advantages comparing to the conventional Fenton method such as the absence of the costly pH adjustment and the Fe(III) hydroxide sludge which characterize this treatment process. The Fenton process showed that the combination of [H2 O2] = 2.00M/[Fe2+] = 0.70 M was the best and archived COD removal of 80%. The treatments studied in this research have achieved high COD removal, but the wastewater from the biodiesel purifi cation stage presents very high parametric values of Chemical Oxygen Demand (667,000 mgO2 /L), so the final COD concentration reached is still above the emission limit of discharge in surface water, according the Portuguese Law (Decree-Law 236/98). However, both treatments have proved to be feasible techniques for the pre-oxidation of the wastewater under study and can be considered as a suitable pre-treatment for this type of wastewaters. A rough economic analysis of both processes was, also, made

Utility function estimation: The entropy approach

The maximum entropy principle can be used to assign utility values when only partial information is available about the decision maker’s preferences. In order to obtain such utility values it is necessary to establish an analogy between probability and utility through the notion of a utility density function. In this paper we explore the maximum entropy principle to estimate the utility function of a risk averse decision maker

Flexible-lean processes optimization: A case study in stone sector

During the downturn in demand in Engineering and Construction Architecture (AEC) activities registered in 2007, the Cluster of Mineral Resources of Portugal (CPMR) put into practice an initiative to boost the Ornamental Stone sector, based on incorporating lean thinking concepts, combined with techniques and technologies to make production processes more flexible. This was called the leanstone hornbook (LH). Since then, the LH has been adopted by several Portuguese Ornamental Stone (OS) companies. For these companies, using the LH means changing their operations to a new model based on (i) their participation in R&D consortium projects, (ii) incorporating the resulting innovations, and (iii) combining innovation with lean thinking. Based on a convenience sample of OS companies, the objective of this research was to assess the economic-financial impact of leanstone operations on Portuguese OS companies. Through a methodological framework based on Key Performance Indicators (KPI) and Innovation Outcomes (IO), indexed to companies’ economic-financial performance, LH was found to generate a potentially positive impact in terms of sales volume, exports, investment capacity and net result.info:eu-repo/semantics/publishedVersio

Improving Industry 4.0 | A Service Science Perspective

Traditionally, customers were considered to be destructive value stakeholders, independent of products, and distant from production sites. Industry 4.0 is a hot and relevant topic, driven by digital technologies, which has made it possible to incorporate a new economic dimension: the consumer collaborates with the producer in the co-creation of products. Service Science is a multidisciplinary scientific discipline, which studies the interactions between abstract entities called service systems. Considering that value is the result of collaborative interactions between service systems, Service Science appears to be one of the most important emerging scientific fields suitable in the approach and development of Industry 4.0. Given this apparent alignment between the mindset of Industry 4.0 and the philosophical base of the Service Science, the following question arises: How to address Industry 4.0 through the Service Science? As a methodology to find a possible answer to this question, we started from a literature review, in which divergences and gaps between the Service Science Body of Knowledge and its philosophical basis Service-Dominant Logic were explored and identified. The main goal is to understand the potential tension of these two approaches in the context of Industry 4.0. Once the divergences gaps identified, a conceptual framework is conceptualized, through which, the creative interactions of Industry 4.0 can be enhanced and scaled use of Service Science’s Theory