Disability and care dependency of older adults

Each chapter corresponds to a scientific article published, submitted or in preparation for submission to a peer-reviewed journal. I am the only author or lead author in all papers. The first article, “Transitions across states with and without difficulties in performing activities of daily living and death: a longitudinal comparison of ten European countries” is of my authorship and is under review in the European Journal of Ageing (submitted in November 2022). In the second article, “Dependency change with aging and associated factors in Uruguay: a cohort study", I am the first and corresponding author and the coauthors are Maximiliano Machado and Graciela Muniz Terrera. This paper was published in Journal of Aging and Health ( see https://doi.org/10.1177/08982643211017726 ). The third article, “Opera tionalization of care dependence in community - dwelling older adults: a systematic review”, is in preparation for submission to Journal of Epidemiology & Community Health. I am the first and corresponding author and the coauthors are Maira Colacce, Julia Córdoba and Graciela Muniz Terrera. This work is part of the project “Programa de Inclusión Social 2019, ID 28, Caracterización y proyección de la población en situación de dependencia en Uruguay” funded by Comisión Sectorial de Investigación Científica, Universidad de la República, Uruguay.Transitions across states with and without difficulties in performing activities of daily living and death: a longitudinal comparison of ten European countries -- Dependency change with aging and associated factors in Uruguay: a cohort study -- Opera tionalization of care dependence in community - dwelling older adults: a systematic review

When size makes a difference: allometry, life-history and morphological evolution of capuchins (Cebus) and squirrels (Saimiri) monkeys (Cebinae, Platyrrhini)

BACKGROUND: How are morphological evolution and developmental changes related? This rather old and intriguing question had a substantial boost after the 70s within the framework of heterochrony (changes in rates or timing of development) and nowadays has the potential to make another major leap forward through the combination of approaches: molecular biology, developmental experimentation, comparative systematic studies, geometric morphometrics and quantitative genetics. Here I take an integrated approach combining life-history comparative analyses, classical and geometric morphometrics applied to ontogenetic series to understand changes in size and shape which happen during the evolution of two New World Monkeys (NWM) sister genera. RESULTS: Cebus and Saimiri share the same basic allometric patterns in skull traits, a result robust to sexual and ontogenetic variation. If adults of both genera are compared in the same scale (discounting size differences) most differences are small and not statistically significant. These results are consistent using both approaches, classical and geometric Morphometrics. Cebus is a genus characterized by a number of peramorphic traits (adult-like) while Saimiri is a genus with paedomorphic (child like) traits. Yet, the whole clade Cebinae is characterized by a unique combination of very high pre-natal growth rates and relatively slow post-natal growth rates when compared to the rest of the NWM. Morphologically Cebinae can be considered paedomorphic in relation to the other NWM. Geometric morphometrics allows the precise separation of absolute size, shape variation associated with size (allometry), and shape variation non-associated with size. Interestingly, and despite the fact that they were extracted as independent factors (principal components), evolutionary allometry (those differences in allometric shape associated with intergeneric differences) and ontogenetic allometry (differences in allometric shape associated with ontogenetic variation within genus) are correlated within these two genera. Furthermore, morphological differences produced along these two axes are quite similar. Cebus and Saimiri are aligned along the same evolutionary allometry and have parallel ontogenetic allometry trajectories. CONCLUSION: The evolution of these two Platyrrhini monkeys is basically due to a size differentiation (and consequently to shape changes associated with size). Many life-history changes are correlated or may be the causal agents in such evolution, such as delayed on-set of reproduction in Cebus and larger neonates in Saimiri

Directional selection effects on patterns of phenotypic (co)variation in wild populations.

Phenotypic (co)variation is a prerequisite for evolutionary change, and understanding how (co)variation evolves is of crucial importance to the biological sciences. Theoretical models predict that under directional selection, phenotypic (co)variation should evolve in step with the underlying adaptive landscape, increasing the degree of correlation among co-selected traits as well as the amount of genetic variance in the direction of selection. Whether either of these outcomes occurs in natural populations is an open question and thus an important gap in evolutionary theory. Here, we documented changes in the phenotypic (co)variation structure in two separate natural populations in each of two chipmunk species (Tamias alpinus and T. speciosus) undergoing directional selection. In populations where selection was strongest (those of T. alpinus), we observed changes, at least for one population, in phenotypic (co)variation that matched theoretical expectations, namely an increase of both phenotypic integration and (co)variance in the direction of selection and a re-alignment of the major axis of variation with the selection gradient

Ship propeller induced scour of non-cohesive sediment in low bed-clearance conditions

Ships maneuvering in low bed clearance conditions induce sediment scour due to the high speed jet generated by a rotating propeller. Sediment scour is known to cause instability to quay structures, damage to the bed protection and may create huge accretion areas reaching extremely low depths, preventing the free passage of large ships. This on-going problem is linked to the constant increase in commercial ship sizes and is widely recognized in current harbor management guidelines. This thesis presents in the first place the experimental work carried out to study the effects of two common propeller systems over the sediment bed: single and twin propellers. Next, the analysis of a case study is used to evaluate the impact of ship maneuvers over the seabed in a particular harbor basin. The first part of the thesis presents a set of experiments in propeller jet velocity and bed shear stresses. By measurements performed in a point-by-point grid, with a Pitot-static tube coupled to differential pressure sensors, the axial velocity distribution at the so-called efflux plane is characterized. After that, direct measurements of bed shear stress are performed at several speeds of rotation and two bed-clearance distances with a shear plate. Velocity and bed shear stress measurements are related by an empirical friction coefficient, which is dependent on the bed clearance. A new empirical model is presented to estimate the mean shear stress in case of unconfined ship propeller jets in low bed clearance conditions. The second part of this work shows the results of a new set of experiments in local scour due to confined twin propeller jets. The maximum scour depth is studied as a function of the bed clearance, the wall clearance and the efflux velocity of the jet. Aiming to reproduce more realistic maneuvers, scour due to forward and backward rotation of the propellers is analyzed, showing a different behavior compared to the traditional experiments with only forward rotation. The obtained results are compared to the existing formulae and later used to propose two different empirical models, one for each regime of rotation. A new non-dimensional parameter obtained from the Buckingham Pi analysis, proposed as Wall Froude number, is used to find a threshold triggering the scouring mechanism. The experimental results show that the distance to the vertical wall is the main contributor to the higher scour depths rather than the bed clearance. The last part of the thesis presents a case study that is used to relate the maneuvers of the ship with the scour observed in an inner basin of the port. The study ship characteristics are obtained from the port statistics. The morphological evolution of the seabed is analyzed through hydrographic surveys of the last decade, which allows characterizing the erosion pattern. Through AIS data, the maneuver of the study ship is analyzed and used as an input maneuver in a simulator. The maneuver is reproduced to obtain the behavior of the main engines and bow thrusters. The maneuvering pattern and the behavior of the engines are used to assess the most damaging maneuvering sections, which turns out to be the ship's lateral approach to the berth, during the arrival maneuver, and the early stages of the departure maneuver.Els vaixells que maniobren en condicions de calat reduït poden provocar erosió local del llit de sediments a causa del raig d'aigua d'alta velocitat generat per les hèlix. L'erosió causa inestabilitat en les estructures dels molls, danys a la protecció del llit i pot crear grans àrees d'acreció, posant en risc la seguretat en la navegació. Aquest fenòmen està relacionat en gran mesura amb l'augment de les dimensions dels vaixells comercials en les darreres dècades i és àmpliament reconegut en les guies actuals de gestió portuària. Aquesta tesi presenta, en primer lloc, el treball experimental realitzat per estudiar els efectes erosius provocats per dos dels sistemes de propulsió més comuns: hèlix convencional i sistema de doble hèlix. A continuació, s'utilitza l'anàlisi d'un cas pràctic per avaluar l'impacte de les maniobres dels vaixells sobre el fons marí en una dàrsena portuària concreta. A la primera part de la tesi es presenten i s'analitzen en un conjunt de mesures experimentals de velocitat del flux d'aigua a la sortida de l'hèlix i de tensions de tall sobre un llit horitzontal. La distribució de velocitats axials es caracteritza a partir de mesures puntuals preses amb un sistema de tub de Pitot-estàtic acoblat a sensors de pressió diferencial. Posteriorment es realitzen mesures directes de les tensions de tall al llit amb una placa de tensions (shear plate) a tres velocitats de rotació de l'hèlix i dues distàncies verticals sobre el llit. Les mesures de la velocitat i la tensió de tall es relacionen amb un coeficient de fricció empíric que és dependent de la distància al llit. A la segona part d'aquest treball es presenta un nou conjunt d'experiments en erosió local per sistemes de doble hèlix confinats. La profunditat màxima d'erosió s'estudia en funció de la distància al sòl, la distància a la paret i la velocitat de sortida del raig d'aigua. Amb l'objectiu de reproduir maniobres de vaixells en entorns portuaris, s'analitza l'erosió generada pels sistemes de doble hèlix en règim combinat, és a dir, avant i invertit. Els resultats mostren diferències respecte els experiments tradicionals en què només es considera la rotació avant. Per estimar l'evolució temporal de la màxima profunditat d'erosió es proposen dos models empírics, un per a cada règim de rotació. De l'anàlisi de Pi de Buckingham s'obté un nou paràmetre adimensional que, proposat com a nombre de Froude del mur, permet establir un llindar d'erosió. Els resultats experimentals també mostren que la distància al mur vertical està més relacionada amb les majors profunditats d'erosió que amb la distancia al sòl. La darrera part de la tesi presenta un cas d'estudi en què les maniobres del vaixell es relacionen amb els canvis en la morfologia portuària observada al llarg del temps. El vaixell d'estudi s'obté a partir de les estadístiques d'ús de les dàrsenes portuàries. L'evolució morfològica del fons marí s'analitza mitjançant estudis hidrogràfics de la darrera dècada, que permet caracteritzar el patró d'erosió. A través de dades AIS, s'analitza la maniobra del vaixell d'estudi i s'utilitza com a model de maniobra en un simulador. La maniobra es reprodueix al simulador, d'on se n'extreu el comportament dels motors principals i de les hèlix de maniobra. El patró de maniobra i el comportament dels motors s'utilitzen per avaluar les seccions de maniobra més perjudicials, que resulten ser l'aproximació lateral del vaixell al moll d'atrac, durant la maniobra d'arribada, i les primeres etapes de la maniobra de sortida.Postprint (published version

Evolutionary processes and its environmental correlates in the cranial morphology of western chipmunks (Tamias).

The importance of the environment in shaping phenotypic evolution lies at the core of evolutionary biology. Chipmunks of the genus Tamias (subgenus Neotamias) are part of a very recent radiation, occupying a wide range of environments with marked niche partitioning among species. One open question is if and how those differences in environments affected phenotypic evolution in this lineage. Herein we examine the relative importance of genetic drift versus natural selection in the origin of cranial diversity exhibited by clade members. We also explore the degree to which variation in potential selective agents (environmental variables) are correlated with the patterns of morphological variation presented. We found that genetic drift cannot explain morphological diversification in the group, thus supporting the potential role of natural selection as the predominant evolutionary force during Neotamias cranial diversification, although the strength of selection varied greatly among species. This morphological diversification, in turn, was correlated with environmental conditions, suggesting a possible causal relationship. These results underscore that extant Neotamias represent a radiation in which aspects of the environment might have acted as the selective force driving species' divergence

Modularity, Noise and natural selection

Most biological systems are formed by component parts that to some degree are inter-related. Groups of parts that are more associated among themselves and are relatively autonomous from others are called modules. One of the consequences of modularity is that biological systems usually present an unequal distribution of the genetic variation among variables. Estimating the covariance matrix that describes these systems is a difficult problem due to a number of factors such as poor sample sizes and measurement errors. We show that this problem will be exacerbated whenever matrix inversion is required, as in directional selection reconstruction analysis. We explore the consequences of varying degrees of modularity and signal-to-noise ratio on selection reconstruction. We then present and test the efficiency of available methods for controlling noise in matrix estimates. In our simulations, controlling matrices for noise vastly improves the reconstruction of selection gradients. We also perform an analysis of selection gradients reconstruction over a New World Monkeys skull database in order to illustrate the impact of noise on such analyses. Noise- controlled estimates render far more plausible interpretations that are in full agreement with previous results

Unidad de separación de gases ácidos de GNL de la planta Gorgon en Barrow Island

La evolución del incremento de la demanda de gas natural tiene su origen en la depreciación del precio de la materia prima frente a otras fuentes de energía, como el carbón y los combustibles líquidos. Este hecho ha ocasionado un aumento de la inversión en las instalaciones de procesado de Gas Natural Licuado (GNL). El gas natural proveniente del yacimiento, contiene contaminantes, que han de ser extraídos para su correcta manipulación en el proceso de licuefacción del GNL. El objetivo del presente Trabajo de Fin de Grado es el de diseñar y simular la Unidad de Separación de Gases Ácidos del Proyecto Gorgon (Australia). En la actualidad se utilizan distintos tipos de aminas para eliminar el contenido de gases ácidos (CO2 y H2S) del gas natural. En particular la combinación de Metildietanolamina con otros solventes formulados, mejora la eficiencia de la captura y por ello, ha sido el proceso con mayor repercusión de la última década. Basado en la bibliografía pública del Proyecto Gorgon y las tecnologías actuales de solución de aminas, se consigue simular las condiciones reales de la unidad de separación de gases ácidos. Así mismo, facilita la identificación de los parámetros de operación del proceso, su optimización y el dimensionamiento de los equipos. El trabajo concluye con un análisis económico y un análisis de sensibilidad frente al VAN y TIR de dos parámetros fundamentales de la instalación

O padrão de reprodução do capital e um caminho para entender o neodesenvolvimento

XX Encontro Nacional de Economia Política: desenvolvimento Latino-Americano, Integração e Inserção Internacional - UNILA, Foz do Iguaçu, 26 a 29 de maio de 2015O objetivo do presente trabalho é introduzir as bases do pensamento de Ruy Mauro Marini, através de sua análise da economia brasileira pela ótica do ciclo de capital. Pretende-se apresentar alguns conceitos introduzidos pela retomada crítica da teoria marxista da dependência, em especial o de padrão de reprodução do capital, já iniciado por Marini. Espera-se assim poder fornecer ferramentas para realizar uma análise da atual condição da América Latina, desmistifi cando os diagnósticos convencionais sobre o tema, e revelando que o subdesenvolvimento ainda se reproduz e se amplia na regiãoBanco Nacional de Desenvolvimento Econômico e Social (BNDES); Usina Hidrelétrica de Itaipu (ITAIPU); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) e Universidade Federal da Integração Latino-Americana (UNILA

Marini ontem e hoje: Pontuações sobre a teoria Marxista da dependência e novas perspectivas

O objetivo do presente trabalho é introduzir as bases do pensamento de Ruy Mauro Marini, através de categorias centrais como dependência, inserção subordinada e superexploração da força de trabalho. Pretende-se também apresentar alguns conceitos introduzidos pela retomada crítica da teoria marxista da dependência, em especial o de padrão de reprodução do capital. Espera-se assim poder fornecer ferramentas para realizar uma análise da atual condição da América Latina, desmistificando os diagnósticos convencionais sobre o tema, e revelando que o subdesenvolvimento ainda se reproduz e se amplia na região

Trayectoria nutricional y desempeño escolar : una aplicación de modelos conjuntos para datos longitudinales y de sobrevivencia

El estudio del estado nutricional y su trayectoria a lo largo de la vida es relevante, pero cobra mayor importancia durante la infancia ya que los problemas en este período de la vida pueden tener efectos adversos de corto y largo plazo en varias dimensiones incluyendo, entre otras, la educación y la salud. Este trabajo analiza la trayectoria nutricional de una cohorte de niños y niñas de Uruguay en edad escolar y su vínculo con el desempeño educativo mediante la estimación de Modelos Mixtos de Clases Latentes y Modelos Mixtos Conjuntos de Clases Latentes. Esta metodología se enmarca en los modelos estructurales y permite analizar el cambio con la edad del estado nutricional, medido a través del Indice de Masa Corporal (IMC). Además, estos modelos suponen que no es posible capturar la heterogeneidad entre individuos por ninguna variable observada y, por tanto, esta queda representada mediante la pertenencia a grupos latentes.Los modelos ajustados identificaron tres grupos de niños y niñas según sus trayectorias nutricionales en el período escolar (entre 6 y 12 a~nos aproximadamente). El 50% de las niñas tiene un IMC dentro de los niveles normales para la edad, el 40% presenta una trayectoria normal aunque con niveles más altos que la mediana y que en algunas edades supera el umbral de sobrepeso. Por último, el 10% de niñnas presenta problemas de sobrepeso en edad escolar. Por su parte, el 70% de los niños tiene una trayectoria normal para la edad, el 20% supera el umbral de sobrepeso para edades más altas y el 10% el de obesidad en todo el tramo de edad considerado. El grupo de ni~nas con sobrepeso se caracteriza por mayor peso y talla al nacer. Sin embargo, no se encuentran diferencias en términos del nivel educativo de las madres. Para los niños, el grupo por encima del umbral de obesidad tiene mayor peso al nacer que el resto de grupos pero la talla no presentó diferencias significativas. Además, hay una mayor proporción de madres con nivel educativo terciario en los grupos con sobrepeso y obesidad. En cuanto a la relación entre trayectoria nutricional y desempeño escolar, los evidencia muestra que los niños abandonan a edades más tempranas que las niñas. Sin embargo, los grupos según trayectorias nutricionales no presentan diferencias en la edad de abandono escolar. Los resultados de este trabajo indican que si bien ninguno de los grupos identificados muestra características de déficit nutricional o decrecimiento del IMC en el período escolar, sí se observa un conjunto de niñas y niños con problemas de sobrepeso u obesidad que podría ser objeto de estudio en futuras investigaciones