A computational model of the evolution of antipredator behavior in situations with temporal variation of danger using simulated robots

The threat-sensitive predator avoidance hypothesis states that preys are able to assess the level of danger of the environment by using direct and in-direct predator cues. The existence of a neural system which determines this ability has been studied in many animal species like minnows, mosquitoes and wood frogs. What is still under debate is the role of evolution and learning for the emergence of this assessment system. We propose a bio-inspired computing model of how risk management can arise as a result of both factors and prove its impact on fitness in simulated robotic agents equipped with recurrent neural networks and evolved with genetic algorithm. The agents are trained and tested in environments with different level of danger and their performances are ana-lyzed and compared

Basic emotions and adaptation. A computational and evolutionary model

The core principles of the evolutionary theories of emotions declare that affective states represent crucial drives for action selection in the environment and regulated the behavior and adaptation of natural agents in ancestrally recurrent situations. While many different studies used autonomous artificial agents to simulate emotional responses and the way these patterns can affect decision-making, few are the approaches that tried to analyze the evolutionary emergence of affective behaviors directly from the specific adaptive problems posed by the ancestral environment. A model of the evolution of affective behaviors is presented using simulated artificial agents equipped with neural networks and physically inspired on the architecture of the iCub humanoid robot. We use genetic algorithms to train populations of virtual robots across generations, and investigate the spontaneous emergence of basic emotional behaviors in different experimental conditions. In particular, we focus on studying the emotion of fear, therefore the environment explored by the artificial agents can contain stimuli that are safe or dangerous to pick. The simulated task is based on classical conditioning and the agents are asked to learn a strategy to recognize whether the environment is safe or represents a threat to their lives and select the correct action to perform in absence of any visual cues. The simulated agents have special input units in their neural structure whose activation keep track of their actual "sensations" based on the outcome of past behavior. We train five different neural network architectures and then test the best ranked individuals comparing their performances and analyzing the unit activations in each individual's life cycle. We show that the agents, regardless of the presence of recurrent connections, spontaneously evolved the ability to cope with potentially dangerous environment by collecting information about the environment and then switching their behavior to a genetically selected pattern in order to maximize the possible reward. We also prove the determinant presence of an internal time perception unit for the robots to achieve the highest performance and survivability across all conditions

Análise de repetições em dados biológicos

The decoding of the genomes has created new challenges on the scientific community linked to the area of computation and information technologies. Daily, new data is added to numerous databases with billions of records, coming from more advanced equipment, helping in decoding the genomes. Determine how important and relevant are these data in order to find value-added information and obviously turn them into knowledge,is the main challenge for the bioinformatics research community. The analysis of genomes and proteomes of several organisms allow us to observe the behaviour at the evolution of species. In this study, our focus goes to a particular aspect of this analysis: the repetition of some codons and their amino acids inside several orthologous genes in eukaryotic organisms. Belonging to different stages of evolution, the main objective focuses on achieving results on the evolution of these repetitions over millions of years. We now know that these repetitions in humans are the source of several neurodegenerative diseases among others. This analysis will verify the conservation or repression, of these repetitions throughout the process of speciation as well at the level of relationship that may exist between these repetitions and those diseases. For this study we have developed an algorithm for A descodificação dos genomas veio criar novos desafios na comunidade científica ligada à área da computação e da informática. Diariamente são alimentadas inúmeras bases de dados com biliões de registos provenientes de equipamentos cada vez mais evoluídos, que auxiliam na descodificação dos genomas. Determinar o quão importante e relevante são esses dados, de forma a retirar valor acrescentado – informação, e obviamente transformá-los em conhecimento, é o grande desafio actual para a comunidade de investigadores de bioinformática. A análise de genomas, bem como dos proteomas dos vários organismos permitem-nos observar o comportamento ao nível da evolução das espécies. Neste estudo focamos a atenção num aspecto particular dessa análise: as repetições de determinados codões e dos respectivos aminoácidos nos vários organismos eucariotas, especificamente em genes ortólogos. Pertencente a várias fases da evolução das espécies, o objectivo principal centra-se na obtenção de resultados quanto à evolução dessas repetições ao longo de milhões de anos. Sabemos hoje que essas repetições no ser humano são a causa de diversas doenças neuro-degenerativas, entre outras, pelo que esta análise permitirá verificar o estado de conservação ou repressão, dessas repetições ao longo do processo de especiação, bem como ao nível do relacionamento que poderá existir entre essas repetições e as doenças nos seres superiormente evoluídos. Para este estudo foi desenvolvido um algoritmo de detecção de padrões de repetição, que possibilita uma análise detalhada da localização de uma determinada sequência, bem como das sequências que melhor se ajustam ao padrão de repetição inicial.Centro de Estudos em Educação, Tecnologias e Saúd

Chorioallantoic and yolk sac placentation in the plains viscacha (Lagostomus maximus) - A caviomorph rodent with natural polyovulation

Objectives: Reproduction in the plains viscacha is characterized by the polyovulation of hundreds of oocytes, the loss of implantation and the development of 1-3 offspring. Our goal was to determine whether placental development was affected by these specializations. Study design: Thirteen placentas from early pregnancy to near-term pregnancy were analyzed using histological, immunohistochemical and transmission electron microscopy. Results: An inverted, villous yolk sac was present. Placentas were formed by the trophospongium, labyrinth and subplacenta. A lobulated structure with a hemomonochorial barrier was established early in pregnancy. Proliferating trophoblast that was clustered at the outer border and inside the labyrinth was responsible for placental growth. Trophoblast invasion resulted from the cellular trophoblast and syncytial streamers derived from the subplacenta. Different from other caviomorphs, numerous giant cells were observed. Conclusions: The principle processes of placentation in caviomorphs follow an extraordinarily stable pattern that is independent of specializations, such as polyovulation.Facultad de Ciencias Veterinaria

Using Online Role-playing Games for Entrepreneurship Training

This edited collection of chapters explores the application, potential and challenges of game-based learning and gamification across multiple disciplines and sectors, including psychology, education, business, history, languages and the ..

Morfologia dos órgãos genitais do macho do Lobo marinho (Arctocephalus australis) e implicações biológicas

Male capacity for spreading genes to a great number of descendents and to determine population dynamics depend directly on the genital organs. Morphological studies in pinnipeds are scarce and the functional meaning of some characteristics has never been discussed. We hypothesized that Arctocephalus australis (A. australis) shows morphophysiological adaptations in order to guarantee the perpetuation of the species in the unique annual mating season. Seven males, dead from natural causes, had their genital organs collected and fixed for morphological description. Some features differ from other described mammalian males and are closely related to the biology and reproductive cycle of this species, as the scrotal epidermis, absence of glandular portion in the ductus deferens and spermatogenic epithelium suggest a recrudescent testis period. The corona glandis exhibits a singular arrangement: its erectile border looks like a formation of petals and its association with the os penis gives a "lily-flower" form to this region. We propose the name margo petaliformis to this particular erectile border of the corona glandis because of its similarity to a flower corola. The male genital organs of A. australis show morphological features compatible with adaptation to environment requirements and reproductive efficiency

Characterization of the fetal membranes in buffalo cows in the first three months of gestation

Este estudo visou à caracterização das membranas fetais em búfalas (Bubalus bubalis, Linnaeus 1758) no terço inicial da gestação. As membranas fetais foram analisadas macroscópica e microscopicamente (luz e microscopia eletrônica de transmissão). O córion possui uma camada simples de células circulares, com núcleos de forma esférica, denominadas trofobláticas; há outro tipo celular, as células trofoblásticas gigantes, com dois ou mais núcleos. Ambas possuem uma grande quantidade de vesículas no citoplasma e retículo endoplasmático à microscopia de transmissão. O alantóide possui vasos preenchidos com eritrócitos, e contêm células alongadas, que formam um epitélio estratificado simples. O âmnion é uma membrana transparente, ou esbranquiçada; constituído por epitélio estratificado simples. A diferença principal entre o alantóide e o âmnion é que o último é avascular. O saco vitelínico é uma membrana opaca que desaparece durante a gestação; é a única membrana que não está em contato com as outras e apresenta três tipos diferentes de células que dão forma a três camadas distintas (endoderma, mesotélio, mesênquima)The aim of the study was to characterize the fetal membranes in buffalo cows (Bubalus bubalis, Linnaeus 1758) in the first 3 months of the gestation. The fetal membranes were analyzed gross and microscopically (light and ultrastructural analysis). The corion is a simple layer of circle cells, with spherical nucleus, named trofoblastics; there is another cellular type, named trophoblastic giant cells, with two or more nucleus. Both of them have many cytoplasmic and reticule endoplasmic vesicles on transmission electron microscopy. The allantoic has many vessels filled with eritrocytes, elongated cells which form a stratified simple epithelium. The amnion is transparent or sometimes whitish, consisting of a stratified simple epithelium. The main difference between the allantoic and amnion is that the latter is avascular. The yolk sac is an opaque membrane that disappears during gestation, and is the only membrane that is not in contact with the others; it presents three different types of cells which form three distinct layers (endoderm, mesothelium and mesenquimal