Introducción de las cadenas de Markov al sistema educativo

Treballs Finals de Grau de Matemàtiques, Facultat de Matemàtiques, Universitat de Barcelona, Any: 2022, Director: David Márquez[en] Markov chains are discrete stochastic processes without memory. The main goal of this project is to study them in order to achieve a university elective proposal focused on them. As the general topic is so extensive, the main focus will be on the study of discrete-time strings, more specifically on homogeneous strings with discrete time variables and their classification

Hábitats biogénicos como reguladores de la variabilidad de las comunidades bentónicas de invertebrados en la bahía de Tongoy (costa del Pacífico SE): implicaciones de la cosecha de macroalgas

Habitat biogenic complexity is thought to exert a significant positive influence on benthic communities. We examined the link between the seasonal variability of macroinvertebrate community structure (species and trophic richness, diversity and biomass) and habitats with different macroalgal assemblages. We identified macroinvertebrates and algae from 336 samples spread over four types of habitat: sand, mud, sand-gravel and seagrass meadows. Considering the whole macroalgal and macroinvertebrate assemblage, we confirmed that macroinvertebrate community variability within and among habitats can be mainly (but not only) explained by a few macroalgal structuring species. The variability of macroinvertebrate communities between habitats and seasons depended on the changes in the relative contribution of the explanatory biostructuring species in the overall algal community. Biomass, trophic behaviour and species richness remained stable in habitats with conspicuous macroalgal communities in contrast with habitats devoid of macroalgae. However, invertebrate species richness and biomass remained stable only in habitats whose dominant species did not change between seasons and not in those where dominant structuring species shifted. The seasonal change in a key structuring macroalgal species (Condracanthus chamissoi), probably as a result of harvesting, led to a major reduction in invertebrate community biomass and richness both in the particular habitat and in those nearby at species level. These consequences are especially important for invertebrates linked by trophic relationships and targeted by fisheries.La complejidad biogénica del hábitat ejercería una importante influencia positiva sobre las comunidades bentónicas. Examinamos la relación entre la variabilidad estacional de la estructura de las comunidades de macroinvertebrados (riqueza, diversidad y biomasa de especies y grupos tróficos) en hábitats con diferentes ensambles de macroalgas. Identificamos macroinvertebrados y algas en 336 muestras distribuidas en cuatro tipos de hábitats: arena, lodo, arena-grava y praderas de pastos marinos. En este estudio, considerando todo el conjunto de macroalgas y macroinvertebrados, confirmamos que la variabilidad de la comunidad de macroinvertebrados dentro y entre los hábitats puede ser explicada principalmente (pero no sólo) por unas pocas especies estructurantes de macroalgas. La variabilidad de la comunidad de macroinvertebrados entre hábitats y estaciones dependió de los cambios de la contribución relativa de las especies biostructurales explicativas en la comunidad algal. La biomasa, el comportamiento trófico y la riqueza de especies permanecieron estables en los hábitats con comunidades de macroalgas conspicuas, en contraste con los hábitats desprovistos de macroalgas. Sin embargo, la riqueza de especies de invertebrados y la biomasa sólo se mantuvieron estables en los hábitats cuyas especies dominantes no cambiaron entre estaciones, pero no en aquellos en los que las especies estructurantes dominantes cambiaron. El cambio estacional de una especie de macroalga estructurante clave (Condracanthus chamissoi), probablemente debido a su cosecha, tuvo importantes consecuencias en la reducción de la biomasa y la riqueza de la comunidad de invertebrados, tanto en su hábitat como en los hábitats adyacentes. Estas consecuencias son especialmente relevantes para los invertebrados vinculados por relaciones tróficas y que además son recursos pesqueros

SOBRE LA RESPONSABILIDAD FILOSÓFICA. CONOCIMIENTO Y ETHOS

The exercise of the philosophical profession entails a responsibility with an ultimate goal that can be translated as the concern for the common good. Those who love wisdom are committed to practice their profession using the integration of reason and heart trough love. To reassess the practice of the Philosophical Profession in order to answer to the necessities that this extraordinary context demands is an act of responsibility to oneself and to others.El ejercicio de la profesión filosófica conlleva una responsabilidad cuyo fin último puede traducirse en la procuración del bien común. El amante de la Sabiduría se compromete a ejercer su profesión a partir de la integración de la razón y el corazón por medio del amor. Replantearse el ejercicio de la profesión de la Filosofía para responder a las necesidades que este contexto extraordinario demanda, es un acto de responsabilidad hacia uno mismo y hacia los demás

An implemetation of a teleoperated robot control architecture on a PLC and field-bus based plarform

Teleoperated robots are used to perform hazardous tasks that human operators cannot carry out. The purpose of this paper is to present a new architecture (ACROSET) for the development of these systems that takes into account the current advances in robotic architectures while adopting the component-oriented approach. ACROSET provides a common framework for developing this kind of robotized systems and for integrating intelligent components. The architecture is currently being used, tested and improved in the development of a family of robots, teleoperated cranes and vehicles which perform environmentally friendly cleaning of ship-hull surfaces (the EFTCoR project). This paper summarises the features of this project and describes the implementation of ACROSET on a hardware platform based on a PLC (Programmed Logic Controller) SIEMENS SIMATIC S7-300 and the Field-Bus PROFIBUS DP

Food Webs

Ciliates are important elements of the trophic networks of aquatic and terrestrial environments, they can be primary producers (myxotrophs), consumers of bacteria, algae, flagellates, even other ciliates and can serve as food for metazoans, for all the above they are the link between different levels of food webs. The structure of the ciliates varies according to the seasons of the year and depending on the trophic conditions of the aquatic systems. Ciliated communities have modifications and adaptations in response to environmental perturbations. The objective of this chapter is to describe the importance of different trophic groups of ciliates in different ecosystems, including anthropogenic perturbations and their impact on trophic webs

Fístula arteriovenosa femoral postraumática, tratamiento endovascular

ResumenAntecedentesLas fístulas arteriovenosas secundarias a arma de fuego han ido en incremento debido a las cuestiones bélicas, mostrando un beneficio en el manejo endovascular para pacientes hemodinámicamente estables.Caso clínicoSe presenta el caso de un paciente masculino 16años de edad con diagnóstico de fístula arteriovenosa femoral en miembro pélvico izquierdo, que ingresó al Servicio de Cirugía para manejo endovascular. Se realizó procedimiento con stent sin complicaciones, egresando del servicio sin complicaciones. Actualmente en tratamiento anticoagulante y antiagregante.ConclusiónLas fístulas arteriovenosas por debajo de la región inguinal pueden ser tratadas de manera segura con terapia endovascular (mediante stents o embolización) en pacientes hemodinámicamente estables. El objetivo del tratamiento es cerrar el defecto entre la arteria y la vena, obliterando el flujo que la nutre. Este fue el caso de este paciente, con buenos resultados tras la terapia endovascular, con lo que disminuyeron las complicaciones del tratamiento quirúrgico.AbstractBackgroundArteriovenous fistulas secondary to gunshot wounds have been increasing due to military activities, with endovascular treatment showing better results in haemodynamically stable patients.Clinical caseA 16 year-old male with diagnosis of femoral arteriovenous fistula in the left lower extremity was admitted to general surgery for endovascular management. A procedure with stent was performed without complications, and is currently on anticoagulant and antiplatelet treatment.ConclusionArteriovenous fistulas under the inguinal region can be safely treated with endovascular treatment (embolisation or stent) on stable patients. The objective of this therapy is to close the defect between artery and vein. This is the case of a patient with great results due to endovascular treatment, decreasing complications of the surgical treatment

REUTIVAR: Model for Precision Fertigation Scheduling for Olive Orchards Using Reclaimed Water

Olive orchard is the most representative and iconic crop in Andalusia (Southern Spain). It is also considered one of the major economic activities of this region. However, due to its extensive growing area, olive orchard is also the most water-demanding crop in the Guadalquivir River Basin. In addition, its fertilization is commonly imprecise, which causes over-fertilization, especially nitrogen. This leads to pollution problems in both soil and water, threating the environment and the system sustainability. This concern is further exacerbated by the use of reclaimed water to irrigate since water is already a nutrient carrier. In this work, a model which determines the real-time irrigation and fertilization scheduling for olive orchard, applying treated wastewater, has been developed. The precision fertigation model considers weather information, both historical and forecast data, soil characteristics, hydraulic characteristics of the system, water allocation, tree nutrient status, and irrigation water quality. As a result, daily information about irrigation time and fertilizer quantity, considering the most susceptible crop stage, is provided. The proposed model showed that by using treated wastewater, additional fertilization was not required, leading to significant environmental benefits but also benefits in the total farm financial costs