Searching for Order in Body Clocks

Physiological rhythms are central to life. Mammalian behavior and metabolism are organized around the day and night by the regulated action of cell-autonomous clocks that exist throughout our bodies. At the core of this molecular clockwork are multiple coupled feedback loops that generate sustained circadian rhythms in gene expression to ultimately orchestrate mammalian physiology. In this work we provide evidence for the role of metabolism in regulating the core clock. We present genes involved in energetic and redox pathways which we identified to be essential for the robustness of cellular timekeepers to temperature fluctuations. We developed the first computational model for circadian redox oscillations that contributes to the understanding of how cellular redox balance might adjust circadian rates in response to perturbations and convey timing information to the core molecular oscillator. Moreover, we show that our mathematical model can be coupled with prior published models of the transcriptional clockwork resulting in 1:1 entrainment. This experimental-theoretical approach exemplifies the need of a dynamic analysis at the system level to understand complex biological processes and provides insights into how basic timekeeping mechanisms are integrated into cellular physiology. Such knowledge might highlight new ways by which functional consequences of circadian timekeeping can be explored in the context of human health and disease

Directiva 2014/95/UE del Parlamento Europeo y del Consejo de 22 de octubre de 2014 y su transposición a la normativa española

Máster Universitario en Auditoría de Cuentas (M142

Synergies of Multiple Zeitgebers Tune Entrainment

Circadian rhythms are biological rhythms with a period close to 24 h. They become entrained to the Earth’s solar day via different periodic cues, so-called zeitgebers. The entrainment of circadian rhythms to a single zeitgeber was investigated in many mathematical clock models of different levels of complexity, ranging from the Poincaré oscillator and the Goodwin model to biologically more detailed models of multiple transcriptional translational feedback loops. However, circadian rhythms are exposed to multiple coexisting zeitgebers in nature. Therefore, we study synergistic effects of two coexisting zeitgebers on different components of the circadian clock. We investigate the induction of period genes by light together with modulations of nuclear receptor activities by drugs and metabolism. Our results show that the entrainment of a circadian rhythm to two coexisting zeitgebers depends strongly on the phase difference between the two zeitgebers. Synergistic interactions of zeitgebers can strengthen diurnal rhythms to reduce detrimental effects of shift-work and jet lag. Medical treatment strategies which aim for stable circadian rhythms should consider interactions of multiple zeitgebers

Synergies of Multiple Zeitgebers Tune Entrainment

Circadian rhythms are biological rhythms with a period close to 24 h. They become entrained to the Earth’s solar day via different periodic cues, so-called zeitgebers. The entrainment of circadian rhythms to a single zeitgeber was investigated in many mathematical clock models of different levels of complexity, ranging from the Poincaré oscillator and the Goodwin model to biologically more detailed models of multiple transcriptional translational feedback loops. However, circadian rhythms are exposed to multiple coexisting zeitgebers in nature. Therefore, we study synergistic effects of two coexisting zeitgebers on different components of the circadian clock. We investigate the induction of period genes by light together with modulations of nuclear receptor activities by drugs and metabolism. Our results show that the entrainment of a circadian rhythm to two coexisting zeitgebers depends strongly on the phase difference between the two zeitgebers. Synergistic interactions of zeitgebers can strengthen diurnal rhythms to reduce detrimental effects of shift-work and jet lag. Medical treatment strategies which aim for stable circadian rhythms should consider interactions of multiple zeitgebers.Peer Reviewe

Information sources and election of university: the catalan case

El peso de los servicios de información y documentación en la universidad como factor determinante de elección de los estudiantes para acceder a los estudios superiores ha sido poco estudiado pero es esencial para determinar las políticas de marketing en educación superior, utilizando las tecnologías de la información y la comunicación (TIC). En este artículo analizamos las fórmulas (referencias, visitas, medios de comunicación) que siguen los estudiantes preuniversitarios para conseguir información a partir de un estudio empírico en Cataluña.The weight of the information and documentation services at the university as a choosing determinant factor of students to enter university has been little studied but is essential to determine the policies of higher education marketing, using Information and Communication Technologies (ICT). In this paper we analyze the formulas (references, visits, and media) that follow the pre-university students to get information, thanks to an empiric study in Cataloni

Fuentes de información y elección de universidad : el caso catalán

El peso de los servicios de información y documentación en la universidad como factor determinante de elección de los estudiantes para acceder a los estudios superiores ha sido poco estudiado pero es esencial para determinar las políticas de marketing en educación superior, utilizando las tecnologías de la información y la comunicación (TIC). En este artículo analizamos las fórmulas (referencias, visitas, medios de comunicación) que siguen los estudiantes preuniversitarios para conseguir información a partir de un estudio empírico en Cataluña.The weight of the information and documentation services at the university as a choosing determinant factor of students to enter university has been little studied but is essential to determine the policies of higher education marketing, using Information and Communication Technologies (ICT). In this paper we analyze the formulas (references, visits, and media) that follow the pre-university students to get information, thanks to an empiric study in Catalonia

Función de ILK endotelial en la formación de neoíntima asociada a enfermedades cardiovasculares

En enfermedades cardiovasculares como la aterosclerosis, uno de los principales síntomas patológicos es una remodelación vascular desregulada y la formación de neoíntima en la pared endotelial de los vasos sanguíneos, produciendo de esta manera una disminución de la luz del vaso que puede acarrear problemas mayores. Sabemos que la quinasa ligada a integrinas (ILK) tiene un rol importante en la regulación de este remodelado y formación de neoíntima, así como un papel fundamental en la angiogénesis durante los estados embrionarios, pero su ausencia provoca un incremento de dicha remodelación. Es conocido que durante la aterosclerosis los niveles de ILK van disminuyendo a medida que provoca su enfermedad, aunque la manera por la que ocurre sea desconocida, si sabemos que la ausencia de ILK provoca cambios en la producción de óxido nítrico (NO) y superóxido, que están implicados en la remodelación vascular. Nos planteamos cómo una deleción inducida en la capa endotelial de los vasos sanguíneos podría afectar a al remodelado vascular, dependiente de los niveles de NO y superóxido. La deleción de ILK en el tejido endotelial de ratones provoca un aumento de liberación de superóxido y un descenso en los niveles de NO, aunque sin afectar a la expresión de la óxido nítrico sintasa endotelial (eNOS) encargada de producirla. Este aumento de superóxido y NO provoca la formación de neoíntima en las aortas de ratones a los que hemos inducido una reducción del flujo sanguíneo mediante una ligadura en el propio vaso. La deleción de ILK también aumenta la fosforilación Akt, y el aumento de expresión TGF-β, hechos que seguramente estén relacionados, y sean los causantes de una mayor producción de superóxido. En resumen este estudio sugiere que la ausencia de ILK a nivel endotelial provoca una disminución de NO y un aumento de superóxido, probablemente producidas por un aumento en la presencia de TGF-β, dando así una remodelación de la pared vascular y la formación de neoíntima, hechos importantes en las patologías cardiovasculare

Mujeres trans y el ámbito deportivo: Identidades, cuerpos y vivencias

¿Cómo viven el deporte las mujeres trans? ¿Se sienten totalmente aceptadas y respetadas dentro de los equipos femeninos? ¿Contemplan el deporte, y en última instancia la sociedad, las identidades y cuerpos diversos? Desde una perspectiva cualitativa, pretendo analizar diferentes aportaciones teóricas, discursos de personas trans y experiencias de mujeres trans para poder conocer las exclusiones y discriminaciones a las que pueden enfrentarse tanto dentro como fuera del ámbito deportivo. Para ello, ha sido necesario comprender las nociones de género, sexo e identidad de cara a analizar cómo se interrelacionan entre ellas, derivando en complejas situaciones dentro del deporte que han repercutido en la participación de las mujeres trans en el deporte tal y como se concibe hoy en día, planteado desde dos categorías inamovibles: lo femenino y lo masculino.El estudio de todo lo mencionado irá orientado a una reflexión sobre el papel que tiene la sociedad cisexual en la perpetuación de actitudes, roles y comportamientos que permiten estas exclusiones y discriminaciones. Se planteará, por tanto, un ejercicio de autocrítica para la cisexualidad, puesto que se tomará a la sociedad cisexual como algo que necesariamente debe transformarse para conseguir una sociedad plural y diversa, y abandone su constante rechazo y discriminación a las identidades de género no normativas.<br /

A lack of timing-dependent effects of transcranial direct current stimulation (tDCS) on the performance of a choice reaction time task

Anodal transcranial direct current stimulation (tDCS) can enhance the retention of a previously practiced motor skill. However, the effects of tDCS on the performance of the choice reaction time task are not fully understood. We examined the effects of anodal tDCS over the left primary motor cortex (M1) on the retention of a 4-choice visual-motor reaction time task (4-ChRT). Right-handed healthy participants (n = 100) were randomly assigned to five groups: three groups received anodal tDCS: before (tDCSbefore), during (tDCSduring), or after (tDCSafter) motor practice. In addition, there were two control groups: with (CONmp) and without (CON) motor practice. We evaluated the speed and precision of the 4-ChRT task before (PRE), during, and 24 h (POST) after the interventions. All groups, including the non-stimulation (CONmp) and non-practice groups (CON), improved (p < 0.05) motor retention (Δ4-ChRT: 35.8 ± 36.0 ms). These findings suggest that the tDCS effects over M1 may differ for serial versus choice RT tasks, perhaps due to the different brain areas involved in each motor task

Protected areas as a double edge sword: An analysis of factors driving urbanisation in their surroundings

Protected areas (PAs) are the most effective tools to protect biodiversity and ecosystem services. They have proven to be effective in stopping extensive land use conversion in well-conserved terrestrial ecosystems. However, land cover changes around PAs threaten biodiversity and ecosystem services within their limits and reduce ecological connectivity. In this study, we analysed the urban sprawls on the boundaries of 159 PAs (national, regional, and natural parks) in Spain, using 2.5 and 5 km non-protected buffer zones from 1990 to 2018. We clustered PAs based on biophysical and socio-economic characteristics and modelled urban sprawl in different buffers and periods. Hierarchical clustering revealed three groups of PAs: (a) proximate urban parks, (b) mountainous parks, and (c) parks in the Madrid autonomous region. We found that urbanisation in the surroundings of PAs in Spain has nearly doubled since 1990. General linear models explained a significant proportion of the urbanisation trends observed, with the number of municipalities in the boundary of the PA, the distance to a main road, and the distance to a big city acting as the most important drivers of urban sprawl. Our results also show that some PAs exert significant effects on urbanisation trends in their surroundings through the park-view effect. Finally, we highlight three coexisting phenomena that might explain the observed urban sprawl processes: (a) PAs attracting urbanisation in their surroundings due to the park-view effect, (b) PAs as a deterrent for urban sprawl within their limits, and (c) PAs occupying residual areas among previously urbanised landsThis study was supported by the project ECOGRADIENTES, funded by the Spanish Ministry of Economy and Competitiveness (CGL2014- 53782-P