What Are the Driving Forces of Individuals’ Retirement Savings?

The purpose of this paper is to analyze what factors are driving the retirement savings of European individuals and whether there are marked differences in retirement preparation among a sample of European countries. Our evidence is based on a sample of 6,036 individuals from eight European countries. The results show that although the percentage of savers for retirement varies widely across countries, the driving forces of the decision to save for retirement are quite similar. Thus, this decision is positively related to individuals’ age, financial literacy, household income, and saving habit. In addition, the results suggest that country-level institutional factors also play a crucial role in an individual’s retirement attitudes.retirement savings, financial literacy, Europe

Arcobacter butzleri strains isolated from different sources display adhesive capacity to epithelial cells in vitro

Background:  :  :  : The genus Arcobacter, belonging to the family Campylobacteraceae, includes polar flagellated, curved or spiral rod shaped bacteria firstly described as Vibrio/Spirillum organisms and later as aerotolerant Campylobacterlike microorganisms. Currently, this genus comprises nine validated species and a candidatus. Among Arcobacter species, Arcobacter butzleri is recognized as a zoonotic agent and the most common species of the genus isolated from environmental water, food and clinical samples. Recently, this species was considered a serious hazard to human health. However, their pathological properties, potential virulence factors as well as their clinical significance remain uncertain or not completely defined. The aim of this study was to establish the ability of 78 A. butzleri strains isolated from different sources to adhere to HEp-2 cells in vitro. Materials, Methods & Results: All the strains were isolated using first an enrichment medium incubated aerobically at 26 ºc for 48 h. after that, 100 ?l of the broth were streaked onto Arcobacter selective agar plates and incubated at 26 °c for 72 h. all the strains were identified phenotypically using standard assays. Definitive identification was achieved using a multiplex polymerase chain reaction. Adhesive capacity was determined infecting hep-2 cells with the strains under study following scaletsky’s et al. protocol, with slight modifications. An adherent Escherichia coli isolated was included as a positive control, whereas uninoculated cell lines were used as negative controls. Adhesion results were expressed as the percentage of hep-2 cells showing adhering bacteria and the number of bacteria (± sd) adhered to cells was determined. Strains were considered as adherent, if at least 20% of hep-2 cells showed one ore more adhered bacteria. Adherence was also demonstrated by scanning electronic microscopy. All the strains showed adhesive capacity to HEp-2 cells in vitro. The lowest adhesion percentage (27%) was observed in a strain isolated from dog feces. In at least one strain per source it was possible to observe 100% adhesion. The lowest number of adhered bacteria (1.03 ± 1.53) was observed in a strain isolated from river water and the highest number (76.6 ± 5.59), in a strain isolated from duck feces. Discussion: Regardless of their isolation source, the 78 Arcobacter butzleri strains tested in the present study were able to adhere to HEp-2 cells in vitro. This property was demonstrated in different proportions by other authors in strains isolated from environmental, meat and human fecal samples. Electronic scanning microscopy shows curved bacilli adhering to HEp-2 cells forming a microcolony-like arrangement. This may occur in a stepwise mechanism. First, A. butzleri adhere to HEp-2 cells and then, due to their capacity to form biofilms, interbacterial adherence can be expressed. The capacity of A. butzleri to form biofilms attaching to stainless steel, copper and glass has been demonstrated in previous studies. Further studies are necessary to elucidate the molecular and cellular mechanisms accounting for this biological property; and hence, its actual role in the colonization of human and animal intestinal epithelium by A. butzleri

Automatic evolution of programs for procedural generation of terrains for video games: accessibility and edge length constraints

Nowadays the video game industry is facing a big challenge: keep costs under control as games become bigger and more complex. Creation of game content, such as character models, maps, levels, textures, sound effects and so on, represent a big slice of total game production cost. Hence, the video game industry is increasingly turning to procedural content generation to amplify the cost-effectiveness of the efforts of video game designers. However, procedural methods for automated content generation are difficult to create and parametrize. In this work we study a Genetic Programming based procedural content technique to generate procedural terrains that do not require parametrization, thus, allowing to save time and help reducing production costs. Generated procedural terrains present aesthetic appeal; however, unlike most techniques involving aesthetic, our approach does not require a human to perform the evaluation. Instead, the search is guided by the weighted sum of two morphological metrics: terrain accessibility and obstacle edge length. The combination of the two metrics allowed us to find a wide range of fit terrains that present more scattered obstacles in different locations, than our previous approach with a single metric. Procedural terrains produced by this technique are already in use in a real video game

Circulación y recepción de discursos y prácticas en el espacio atlántico: el ejemplo de la ingeniería sanitaria urbana chilena (1871-1905)

The article proposes an analysis of the process of circulation, reception and application of speeches and practices of urban Sanitary Engineering in the Atlantic space. We analyze the interaction between an international movement -the development of sanitary engineering- and Chilean reception conditions from the beginning of the professionalization of Chilean engineers to the inauguration of the sewer works of Santiago de Chile.El artículo propone un análisis del proceso de circulación, recepción y aplicación de discursos y prácticas ligadas con la ingeniería sanitaria que tiene lugar en el espacio atlántico durante el último tercio del siglo XIX y el principio del XX. El foco de atención del trabajo se centra en la interacción existente entre un movimiento internacional, como es el desarrollo de la ingeniería sanitaria, y las condiciones chilenas de recepción entre el comienzo del proceso de profesionalización de los ingenieros chilenos y la inauguración de las obras de alcantarillado de Santiago de Chile

Genetic terrain programming: an aesthetic approach to terrain generation

Comunicação apresentada na conferência Computer Games and Allied Technology, 8, Singapore, 2008.Nowadays there are a wide range of techniques for terrain generation, but are focused on providing realistic terrains often neglecting the aesthetic appeal. The Genetic Terrain Programming technique, based on evolutionary design with Genetic Programming, allows designers to evolve terrains according to their aesthetic feelings or desired features. This technique evolves TPs (Terrain Programmes) that are capable of generating different terrains, but consistently with the same features. This paper presents a study about the perseverance of terrain features of the TPs across different LODs (Levels Of Detail). Results showed it is possible to use low LODs during the evolutionary phase without compromising results and the terrain features generated by a TPs are scale invariant

Breeding terrains with genetic terrain programming: the evolution of terrain generators

Although a number of terrain generation techniques have been proposed during the last few years, all of them have some key constraints. Modelling techniques depend highly upon designer’s skills, time, and effort to obtain acceptable results, and cannot be used to automatically generate terrains. The simpler methods allow only a narrow variety of terrain types and offer little control on the outcome terrain. The Genetic Terrain Programming technique, based on evolutionary design with Genetic Programming, allows designers to evolve terrains according to their aesthetic feelings or desired features. This technique evolves Terrain Programmes (TPs) that are capable of generating a family of terrains—different terrains that consistently present the same morphological characteristics. This paper presents a study about the persistence of morphological characteristics of terrains generated with different resolutions by a given TP. Results show that it is possible to use low resolutions during the evolutionary phase without compromising the outcome, and that terrain macrofeatures are scale invariant

GenTP: uma ferramenta interactiva para a geração artificial de terrenos

Actualmente existe uma grande variedade de técnicas de geração artificial de terrenos. No entanto todas elas estão focadas em fornecer terrenos de aspecto realista, negligenciando por vezes a estética e a criatividade. Este artigo apresenta uma ferramenta interactiva para a geração artificial de terrenos, designada GenTP, inspirada nos sistemas de arte evolutiva com programação genética. Esta ferramenta permite aos designers evoluir TPs (Terrain Programs) de acordo com o seu sentido estético ou características desejadas. Os TPs, o produto desta ferramenta, geram terrenos diferentes a cada execução, mas sempre coerentes nas sua características morfológicas

Rotational Periods of very Young Brown Dwarfs in ChaI

A photometric monitoring campaign of brown dwarfs in the ChaI star forming region in the i and R band revealed significant periodic variations of the three M6.5-M7 type brown dwarf candidates ChaHa2, 3 and 6 (Joergens et al. 2002). These are the first rotational periods for very young (1-5 Myr) brown dwarfs and among the first rotational periods for brown dwarfs at all. The relatively long periods of 2.2 to 3.4 days as well as vsini values (Joergens & Guenther 2001) indicate that our targets are moderately fast rotators in contrast to very rapidly rotating old brown dwarfs. The periods for the ChaI brown dwarf candidates provide valuable data points in an as yet, in terms of rotational characteristic, almost unexplored region of the age-mass diagram. A comparison with rotational properties of older brown dwarfs indicates that most of the acceleration during the contraction phase takes place within the first 30 Myr or less of the lifetime of a brown dwarf. We have also determined periods for the two M5-M5.5 type very low-mass stars B34 and CHXR78C.Comment: Proceeding of poster presentation at the '1st Potsdam Thinkshop on Starspots', May 2002, Potsdam, German

Building a high-resolution site index map using boosted regression trees: The Norwegian case

Accurate estimation of site productivity is essential for forest projections and scenario modelling. We present and evaluate models to predict site index (SI) and whether a site is productive (potential total stem volume production ≥ 1 m3·ha−1·year−1) in a wall-to-wall high-resolution (16 m × 16 m) SI map for Norway. We investigate whether remotely sensed data improve predictions. We also study the advantages and disadvantages of using boosted regression trees (BRT), a machine-learning algorithm, to create high-accuracy SI maps. We use climatic and topographical data, soil parent material, a land resource map, and depth to water, together with Sentinel-2 satellite images and airborne laser scanning metrics, as predictor variables. We use the SI observed at more than 10 000 National Forest Inventory (NFI) sample plots throughout Norway to fit BRT models and validate the models using 5822 independent temporary plots from the NFI. We benchmark our results against SI estimates from forest monitoring inventories. We find that the SI from BRT has root mean squared error (RMSE) ranging from 2.3 m (hardwoods) to 3.6 m (spruce) when tested against independent validation data from the NFI temporary plots. These RMSEs are similar or marginally better than an evaluation of SI estimates from operational forest management plans where SI normally stems from manual photo interpretation.publishedVersio