Use of vitamin D to reduce lameness in broilers reared in harsh environments

In tropical poultry-producing countries, poultry houses usually have little environmental control. This study investigated the effect of dietary vitamin D on the incidence of leg abnormalities of a fast-growing broiler strain reared under harsh conditions. In this study, 300 one-day-old male broilers were distributed in two treatments with three replicates of 50 birds each. One group was fed a placebo and the other group was fed 25-hydroxycholecalciferol (25-OH-D3) in a soluble form. The environmental variables were weekly recorded during until birds were 49 days old. Birds were weekly gait scored, and their walking speed and vertical force while walking were assessed. Post-mortem examination was performed and skeletal lesions were assessed. Control birds presented more leg problems than those that ingested 25-OH-D3. These results suggest that dietary vitamin D is effective in decreasing the severity of lameness by reducing tibial dyschondroplasia and other leg abnormalities.

Macrobenthic intertidal communities from wave to tide dominated beach environments. A case study in two Brazilian beaches

Modification showed by intertidal macrofaunal communities between two nearby sites that change from a wave to a tide dominated beach environment, was analyzed on the present study. At each site, eleven intertidal sampling stations were distributed along a transect, from the drift line to the spring low tide water level. Four macrofaunal samples one meter long-shore spaced were collected at, each station with an iron core of 0.05 m(2) surface area, taken to a depth of 20 cm. Major,differences on sediments between sites were the offshore decrease of mean particle size diameter and increase of kurtosis and water content at the tide dominated site. KIDS ordination showed major similarities between the lowest stations of this site, that represents the dissipative low tide-terrace portion of the beach. Two lower station of the wave dominated site presented similarities with this group. The other stations of the tide-dominated site, that represents the reflective high tide beach portion, grouped distant from the former. (canonical Correspondence Analysis (CCA) showed a similar spatial distribution of stations, suggesting the importance of environmental factors on the explanation of species distribution patterns. Sediment water content and water table depth, with the highest inertia value, seems to be the principal physical factor. Increase on water content affects the macrofaunal distribution by the expansion of typical infralitoral species, as was the case of Bathyporeiapus ruffoi, on the dissipative low tide terrace beach portion. A disrupted distribution with the lost of a gradate zonation along a physical gradient is one of the major modification presented by macrobenthic communities on the transition from a wave to a tide dominated beach environment.

Use of a semantically grained database system for distribution and control within design environments

This paper presents a technique to share the data stored in an object-oriented database aimed at designing environments. This technique shares data between two related databases, called the Original and Product databases, and is composed of three processes: data separation, evolution and integration. Whenever a block of data needs to be shared, it is spread into both databases, resulting in a block on the original database, and another into the Product database, with special links between them controlled by the Object Manager. These blocks do not need to be maintained identical during the evolution phase of the sharing process. Six types of links were defined, and by choosing one, the designer control the evolution and reintegration of the block in both databases. This process uses the composite object concept as the unit of control. The presented concepts can be applied to any data model with support to composite objects.

Support on the remote interaction for augmented reality system

This article presents a support on the remote interaction for utilization in augmented reality systems based on ARToolkit. It utilizes the multicast communication in order to improve the scalability of distributed environment. This support may be utilized in production of specific applications pointed to distance education, training and entertainment. The validity of support happened with the implementation of a prototype and realization of tests for communication latency analysis and frames per second rate. © 2007 IEEE.

The generation of scenes in mixed reality environments using the chromakey technique

A classic problem in the development of Mixed Reality systems is the registration. The correct alignment between virtual objects and the real elements is extremely important for the coherent composition of the resultant scene. Considering this context, this paper describes an approach for the composition of scenes in Mixed Reality environments using the chromakey technique for the extraction of real objects. After that, the scene is mounted in a coherent way related to the depth in OpenGL framebuffer for posterior rendering. ©2007 IEEE.

Virtual simulator for mobile robots navigation systems

This paper presents the virtual environment implementation for project simulation and conception of supervision and control systems for mobile robots, that are capable to operate and adapting in different environments and conditions. This virtual system has as purpose to facilitate the development of embedded architecture systems, emphasizing the implementation of tools that allow the simulation of the kinematic conditions, dynamic and control, with real time monitoring of all important system points. For this, an open control architecture is proposal, integrating the two main techniques of robotic control implementation in the hardware level: systems microprocessors and reconfigurable hardware devices. The implemented simulator system is composed of a trajectory generating module, a kinematic and dynamic simulator module and of a analysis module of results and errors. All the kinematic and dynamic results shown during the simulation can be evaluated and visualized in graphs and tables formats, in the results analysis module, allowing an improvement in the system, minimizing the errors with the necessary adjustments optimization. For controller implementation in the embedded system, it uses the rapid prototyping, that is the technology that allows, in set with the virtual simulation environment, the development of a controller project for mobile robots. The validation and tests had been accomplish with nonholonomics mobile robots models with diferencial transmission. © 2008 IEEE.

Treino prévio reduz o tempo de execução de tarefas visuo-espaciais em ambiente virtual

Objective. To evaluate the influence of previous adaptation to different computational environments in visuo-spacial tasks performance of healthy individuals. Method. Healthy volunteers (n = 30), 15 male, mean age 25.3 ± 3.3 years, were divided in three groups: the first group, considered control, was not adapted to the proposed environments; the second group was adapted to a closed environment (stable and expected), and the third group was adapted to an open environment A (unexpected). The proposed task was to go through two open environments B and C (maze). The dependent variables Time and Error were considered for the analysis. Results. It was observed that during the adaptation phase, in the Time variable, the groups presented a progressive improvement in the performance to each task (p = 0.0036). The group adapted in the A open environment, showed a tendency to be faster in the execution of B and C open environments tasks, than the group adapted in the closed environment (p = 0.068). Conclusion. The study suggests that subjects adapted to visuo-spacial tasks execution involving unknown and no guided situations, present a tendency to a better time performance in these tasks when compared to subjects adapted in fixed and guided situations.

The Owner Share scheduler for a distributed system

In large distributed systems, where shared resources are owned by distinct entities, there is a need to reflect resource ownership in resource allocation. An appropriate resource management system should guarantee that resource's owners have access to a share of resources proportional to the share they provide. In order to achieve that some policies can be used for revoking access to resources currently used by other users. In this paper, a scheduling policy based in the concept of distributed ownership is introduced called Owner Share Enforcement Policy (OSEP). OSEP goal is to guarantee that owner do not have their jobs postponed for longer periods of time. We evaluate the results achieved with the application of this policy using metrics that describe policy violation, loss of capacity, policy cost and user satisfaction in environments with and without job checkpointing. We also evaluate and compare the OSEP policy with the Fair-Share policy, and from these results it is possible to capture the trade-offs from different ways to achieve fairness based on the user satisfaction. © 2009 IEEE.

Mutual occlusion between real and virtual elements in Augmented Reality based on fiducial markers

Augmented Reality (AR) systems which use optical tracking with fiducial marker for registration have had an important role in popularizing this technology, since only a personal computer with a conventional webcam is required. However, in most these applications, the virtual elements are shown only in the foreground a real element does not occlude a virtual one. The method presented enables AR environments based on fiducial markers to support mutual occlusion between a real element and many virtual ones, according to the elements position (depth) in the environment. © 2012 IEEE.

Plataforma de simulação computacional paralela com base nos conceitos de relógios lógicos e tempo virtual

Pós-graduação em Ciência da Computação - IBILCE

A formação inicial do professor de línguas no e para o contexto virtual e a construção de comunidades de prática

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Interação de crenças em contexto colaborativo virtual de aprendizagem de línguas

This article mainly aims at addressing issues of the complexity and dynamics of beliefs in collaborative contexts for language teaching and learning, such as Teletandem. On the assumption that beliefs are dynamic and can be (re)signified, we present some of the results of a research about the interaction of beliefs of two Teletandem partners, a Brazilian and an Italian undergraduate student, addressing moments of convergence and divergence, as well as their possible origins and (re)significations from lived experiences. The results show how the Teletandem context can become a field for conflicts and clashes of beliefs and how the mediation as well as the relationship between the participants becomes essential for the conduction of language learning in collaborative environments.

Algoritmo de escalonamento de instância de máquina virtual na computação em nuvem

Pós-graduação em Ciência da Computação - IBILCE

Information technology as a technical resource for the memories: memories of UNATI-Marília in the virtual environment

UNATI (Open University of the Third Age), UNESP, Marília campus, has offered subsidies for the development of this work aimed at researching the existing relationships between information mediation processes and technological devices, especially computers, assuming that reading practices and textual construction in online environments could help the “third age” population to have access to these devices, thus promoting digital inclusion in this group. Mediation was presented as an interventionist action that, by introducing an intermediate element in the learning process, causes a rupture in the ways of living and personal digital inclusion processes hitherto experienced. In the context of a workshop, we found out that there is a physical relationship between subjects and technological supports and such a contact proved to be necessary, considering that handling a computer required knowledge of procedures, thus furthering a logic of use. It turned out to be necessary to develop actions that would enable the handling of a computer so as to bring about acceptance of these supports. Accordingly, activities were developed so as to articulate reminiscent processes, memories of older adults, the writing down of such memories and the creation of a blog to bring enhanced visibility to the content produced by older people. Such actions have shown that remembering, writing down and posting can reshape not only social relations but somehow significantly promote digital inclusion among older adults.

Educação a distância na sociedade da informação: reflexões acerca dos processos de comunicação, ensino e aprendizagem na sala de aula virtual

Information and communication technologies (ICT) pervade the daily lives of people affecting relations and social subsystems. Education is not unrelated to this process and in this scenario the distance education (EaD). Considering as a starting point the information society and its characteristics, the objective of this paper was to analyze the relationship between the new information and communication technologies, teaching and learning in the virtual classroom, seeking to understand what is the design of teaching and learning inherent in the current generation of EaD. Thus, by means of analytical, descriptive and exploratory research, bibliographic and qualitative approach oriented, it was concluded that ICT has a very important role in the context of EaD, allowing the creation of interactive virtual learning environments that enable communication between teachers, tutors and students, making possible the Exchange and sharing of key information on the teaching and learning process.