Estratégias sintéticas para o ácido nonático

Nonactic Acid is the monomeric unity of the Nactines, an important class of poliether antibiotics. This review focuses on the approaches to the syntheses of the above mentioned unity, which have been accomplished in the period from 1971 to date.

Prices versus exams as strategic instruments for competing universities

In this paper we investigate the optimal choice of prices and/or exams by universities in the presence of credit constraints. We first compare the optimal behavior of a public, welfare maximizing, monopoly and a private, profit maximizing, monopoly. Then we model competition between a public and a private institution and investigate the new role of exams/prices in this environment. We find that, under certain circumstances, the public university may have an interest to raise tuition fees from minimum levels if it cares for global welfare. This will be the case provided that (i) the private institution has higher quality and uses only prices to select applicants, or (ii) the private institution has lower quality and uses also exams to select students. When this is the case, there are efficiency grounds for raising public prices

Oferta de trabajo y análisis impositivo con el ordenador: tutorial y actividad práctica

En el presente documento proponemos un ejercicio tutorial y una práctica docente que permita al estudiante a asimilar y entender mejor el concepto de exceso de gravamen o pérdida irrecuperable de eficiencia asociada a la imposición. Para ello planteamos, en primer lugar, un modelo de elección individual entre ocio y trabajo/consumo. Centrándonos en el individuo representativo, estudiamos su elección de horas de trabajo en ausencia de impuestos. A continuación, introducimos un impuesto proporcional sobre la renta del trabajo y, alternativamente, un impuesto de suma fija capaz de generar una recaudación igual. Verificamos que el impuesto proporcional siempre deja al individuo con un nivel de bienestar inferior respecto al escenario del impuesto de suma fija, es decir, que el impuesto proporcional genera una pérdida irrecuperable de eficiencia. Aunque la resolución manual del problema es factible, proponemos utilizar la herramienta Solver de Excel. Esto nos permite jugar de manera más ágil con los valores de los diferentes parámetros y verificar que hay pérdida de eficiencia independientemente de que el individuo decida trabajar más o menos horas en respuesta a la introducción del impuesto sobre la renta del trabajo

Mutual feedback in e-portfolio assessment : an approach to the netfolio system

Peer-reviewed

Metacognitive presence in asynchronous online learning environments : self, mutual and hetero-regulation

Peer-reviewed

¿Cómo vive nuestro cuerpo las ausencias de un ser querido?

Con esta investigación pretendo utilizar las técnicas de la Danza Movimiento Terapia como una herramienta que ayude en la elaboración de los procesos de duelo, mediante la puesta en movimiento de elementos relacionados con la contratransferencia CT y la contratransferencia somática CTS, apoyándome en la clasificación que hace Fuchs de la memoria corporal. La metodología utilizada es la heurística, en la que trabajo mis duelos pendientes, mediante la realización de 3 talleres vivenciales de DMT (los cuales fueron grabados) con un grupo de terapeutas de duelo, donde ellas debían poner en movimiento las emociones relacionadas con la pérdida de un ser querido. Posteriormente he visto las grabaciones y he ido anotando mis respuestas corporales y emocionales en un documento al que he nombrado Análisis de los talleres (Adlt), lo que me llevó a conectar con algunas emociones contenidas durante muchos años. Me apoyé, además, en un pequeño diario que he llamado Diario de mi tesina (Ddmt), donde registré algunas consideraciones importantes surgidas desde el momento en que decidí realizar mi investigación sobre el duelo. Cada uno de los talleres tenía como objetivo vivenciar un aspecto diferente, es así como en el primero se trabajó con recuerdos relacionados con la infancia, en el segundo los recuerdos incluían la presencia de la persona fallecida y en el tercero se trabajaron aspectos del rol como terapeutas de duelo.

Outer membrane vesicles from cold-adapted antarctic bacteria

Many Gram-negative, cold-adapted bacteria from the Antarctic environment produce large amounts of extracellular matter with potential biotechnological applications. Transmission electron microscopy (TEM) analysis after high-pressure freezing and freeze substitution (HPF-FS) showed that this extracellular matter is structurally complex, appearing around cells as a netlike mesh, and composed of an exopolymeric substance (EPS) containing large numbers of outer membrane vesicles (OMVs). Isolation, purification and protein profiling via 1D SDS-PAGE confirmed the outer membrane origin of these Antarctic bacteria OMVs. In an initial attempt to elucidate the role of OMVs in cold-adapted strains of Gram-negative bacteria, a proteomic analysis demonstrated that they were highly enriched in outer membrane proteins and periplasmic proteins associated with nutrient processing and transport, suggesting that the OMVs may be involved in nutrient sensing and bacterial survival. OMVs from Gram-negative bacteria are known to play a role in lateral DNA transfer, but the presence of DNA in these vesicles has remained difficult to explain. A structural study of Shewanella vesiculosa M7T using TEM and Cryo-TEM revealed that this Antarctic Gram-negative bacterium naturally releases conventional one-bilayer OMVs, together with a more complex type of OMV, previously undescribed, which on formation drags along inner membrane and cytoplasmic content and can therefore also entrap DNA.

El uso de las herramientas digitales 2.0 en la educación primaria en Barcelona

La intenció del present estudi es esbrinar si el propòsit institucional d'integrar les TICs i desenvolupar les competències digitals entre l'alumnat s'assoleix a l'escola primària, si la formació del professorat es suficient per aquests objectius i si l'ús està integrat en el procés d'ensenyament i aprenentatge. També volem saber si a la pràctica les TICs queden relegades només a un nivell individual, deixant en segon pla l'ús col·lectiu dins l'aula amb l'alumnat, i l'ús queda restringit sobre tot a la consulta i no incorpora la producció de material digital.Per tant, el nostre objectiu és conèixer el grau d'utilització de les TICs, en particular les que donen pas i fomenten la cultura participativa (eines 2.0) del professorat de Primària, el tipus d'ús i el coneixement sobre l'alumnat destinatari de l'aprenentatge. Per tal d'obtenir una descripció de la utilització d'aquest col·lectiu de les TICs s'ha creat un qüestionari que intentarà respondre als nostres objectius.

Differential methylation of TCF7L2 promoter in peripheral blood DNA in newly diagnosed, drug-naïve patients with type 2 diabetes

TCF7L2 is the susceptibility gene for Type 2 diabetes (T2D) with the largest effect on disease risk that has been discovered to date. However, the mechanisms by which TCF7L2 contributes to the disease remain largely elusive. In addition, epigenetic mechanisms, such as changes in DNA methylation patterns, might have a role in the pathophysiology of T2D. This study aimed to investigate the differences in terms of DNA methylation profile of TCF7L2 promoter gene between type 2 diabetic patients and age- and Body Mass Index (BMI)- matched controls. We included 93 type 2 diabetic patients that were recently diagnosed for T2D and exclusively on diet (without any pharmacological treatment). DNA was extracted from whole blood and DNA methylation was assessed using the Sequenom EpiTYPER system. Type 2 diabetic patients were more insulin resistant than their matched controls (mean HOMA IR 2.6 vs 1.8 in controls, P<0.001) and had a poorer beta-cell function (mean HOMA B 75.7 vs. 113.6 in controls, P<0.001). Results showed that 59% of the CpGs analyzed in TCF7L2 promoter had significant differences between type 2 diabetic patients and matched controls. In addition, fasting glucose, HOMA-B, HOMA-IR, total cholesterol and LDL-cholesterol correlated with methylation in specific CpG sites of TCF7L2 promoter. After adjustment by age, BMI, gender, physical inactivity, waist circumference, smoking status and diabetes status uniquely fasting glucose, total cholesterol and LDL-cholesterol remained significant. Taken together, newly diagnosed, drug-naïve type 2 diabetic patients display specific epigenetic changes at the TCF7L2 promoter as compared to age- and BMI-matched controls. Methylation in TCF7L2 promoter is further correlated with fasting glucose in peripheral blood DNA, which sheds new light on the role of epigenetic regulation of TCF7L2 in T2D.

Organometallic catalysis: some contributions to organic synthesis

In the present paper some general aspects of metal complex catalysis and its applications for oxyfunctionalization of various olefins, including naturally occurring ones, via selective oxidation, hydroformylation and alkoxycarbonylation are discussed.

Maria de Portugal, una dona amagada per la història

The points of departure of this article are our own researches which talked about Maria of Portugal and widowhood during the 14ht century, respectively. We were interested in the figure of Maria of Portugal as example of all that kind of people, mostly women but also children who were treated as change currency by their relatives. They were used to guaranty peace treaties and other agreements, but also as hostages in war times. This article is based on the study of Maria's will, which is preserved in the Arxiu de la Coroan d'Aaragó. however we also thought necessary to present the figure of Maria of Portugal in order to grasp, not only the events that marked her life, but also the way they influenced in her thoughts an feelings.

Outer membrane vesicles from cold-adapted antarctic bacteria

Many Gram-negative, cold-adapted bacteria from the Antarctic environment produce large amounts of extracellular matter with potential biotechnological applications. Transmission electron microscopy (TEM) analysis after high-pressure freezing and freeze substitution (HPF-FS) showed that this extracellular matter is structurally complex, appearing around cells as a netlike mesh, and composed of an exopolymeric substance (EPS) containing large numbers of outer membrane vesicles (OMVs). Isolation, purification and protein profiling via 1D SDS-PAGE confirmed the outer membrane origin of these Antarctic bacteria OMVs. In an initial attempt to elucidate the role of OMVs in cold-adapted strains of Gram-negative bacteria, a proteomic analysis demonstrated that they were highly enriched in outer membrane proteins and periplasmic proteins associated with nutrient processing and transport, suggesting that the OMVs may be involved in nutrient sensing and bacterial survival. OMVs from Gram-negative bacteria are known to play a role in lateral DNA transfer, but the presence of DNA in these vesicles has remained difficult to explain. A structural study of Shewanella vesiculosa M7T using TEM and Cryo-TEM revealed that this Antarctic Gram-negative bacterium naturally releases conventional one-bilayer OMVs, together with a more complex type of OMV, previously undescribed, which on formation drags along inner membrane and cytoplasmic content and can therefore also entrap DNA.