Educaçãdo matemática na realidade do ciberespaço - Que aspectos ontológicos e científicos se apresentam?

The question that leads this article is What is this virtual space in the on-line mathematics education process? We focus on the question of the real and virtual as issues taken as components of cyberspace. We investigate these notions in the history of philosophy, looking to Granger to find their meaning, to enable us to understand them and fit them into the sphere of Mathematics Education. This theoretical-philosophical article, then, claims that the virtuality of cyberspace is supported by the computer screen, built by the unification of the sciences (mathematics), technology and its applications. Software and the actions taken by Internet users update the capability of these programs in a variety of characteristics and possibilities such as space-time flow interconnections as well as during the mathematics education process.

Evaluación de la deformación de dos siliconas para prótesis faciales, influencia de la pigmentación y desinfección química

The purpose of present study was to analyze the effect of pigmentation and chemical disinfection on the initial and the permanent deformation of two silicones (Silved Selant and Brascoved) for facial prosthesis. Initial and permanent deformation tests samples (20 mm × 12.5 mm) were made following the manufacturer's instructions. For each silicone (n= 40), ten samples were used for pigmentation with make up power, ten with iron oxide, ten with ceramics power and tem were tested without pigmentation. Five samples of each group were submitted to chemical disinfection using a 2 % Chlorhexidine spray. All samples were immersed in physiological saline and stored in an oven at 35 ° ± 1 °C. After 90 days, the samples were submitted to initial and permanent deformation tests using a dial indicator. For both properties, data were analyzed by Tukey's test (a= 0.05). The results showed that all the materials had initial and permanent deformation regardless of pigmentation and chemical disinfection. The groups were used for pigmentation with iron oxide showed less initial and permanent deformation when were submitted to the chemical disinfection regardless the silicone used.

Estética en prótesis removibles

Nowadays, aesthetics is very appreciated in the social context and a attractive smile is the object of desire in most of patients requiring prosthesis treatment. In case of removable prosthesis, total or partial, this feature is more significant since some or all teeth may be absents. Implants leading to a significant improvement in relation to function and comfort of removable prosthesis users, but the aesthetics of these prostheses had little attention in the current scientific literature. Thus, the aim of present article was to make a review of the literature on the aesthetic features related to rehabilitation with removable prostheses. In present study we found as significant factors for the aesthetics in removable partial and total prostheses: Selection of artificial teeth and their arrangement, characterization of acrylic resin basis and also the types and location of retainers for the removable partial prostheses. We conclude that the involvement and the aesthetic knowledge during the appropriate planning of this process is responsibility of the professional.

Utilização de extratos de plantas medicinais e óleo de Eucaliptus no controle in vitro de Microsporum canis

INTRODUCTION: Microsporum canis is the most common cause of canine and feline dermatophytosis and thus has an important zoonotic role. OBJECTIVES: the aim of this study was to determine the antifungal action of medicinal plant extracts and of eucalyptus oil against pathogenic fungus Microsporum canis. METHODS: the extracts were prepared by mixing 300 g of previously washed leaves with 450 mL of distilled water. Then the material was triturated, filtered, sterilized and conserved at 10 + 2 oC. Fifteen milliliters of sterilized medium Sabouraud dextrose (Difco) at a temperature of 55 + 1 oC was added in Petri dishes containing the extracts in one, two, three, four and five mm concentrations. The fungus was inoculated once the medium was solidified. The inoculated dishes were maintained in B.O.D. incubator at 36 ± 0,5 oC until the fungus developed in the controls. RESULTS: the extracts from Punica granatum, Mangifera indica and Eucalyptus spp reduced the growth of fungus, but the extracts from Cymgopogom nardus, Tagetes minuta, Ruta graviolens, Cyperus rotundus, Annona moricata and Calendula spp leaves and flowers boosted the growth of fungus. The other extracts and the eucalyptus oil neither show any fungicidal action nor encourage mycelium growth. CONCLUSIONS: the use of most tested extracts and eucalyptus oil is not suitable for the treatment of Microsporum canis dermatophytosis due to lack of inhibitory effects. The extracts from Cymgopogom nardus, Tagetes minuta, Ruta graviolens, Cyperus rotundus, Annona moricata and from of Calendula spp leaves and flowers help the development of the fungus making clear that phytotherapy should be properly used, otherwise it can worsen the problem. However; extracts from Mangifera indica, Punica granatum and Eucalyptus spp. can be used as fungistatic.

Hardness evaluation of prosthetic silicones containing opacifiers following chemical disinfection and accelerated aging

We evaluated the effects of disinfection and aging on the hardness of silicones containing opacifiers and intended for use in facial prosthetics. A total of 90 samples were produced using a cylindrical metal mold 3 mm in height and 30 mm in diameter. The samples were fabricated from Silastic MDX 4-4210 silicone in three groups: GI contained no opacifier, GII contained barium sulfate (Ba), and GIII contained titanium dioxide (Ti). The samples were disinfected using effervescent tablets (Ef), neutral soap (Ns), or 4% chlorhexidine (Cl) 3 times a week for 60 days. After this period the samples underwent 1,008 hours of accelerated aging. The hardness was measured using a durometer immediately following the disinfection period and after 252, 504, and 1,008 hours of aging. The data were statistically analyzed using 3-way ANOVA and the Tukey test (p < .05). The GIII group exhibited the greatest variation in hardness regardless of elapsed time. All groups displayed greater hardness after 1,008 hours of accelerated aging independent of disinfectant type. All of the hardness values were within the clinically acceptable range.

Caracterização de programas de intervenção com crianças e/ou adolescentes

The objective was to present a descriptive analysis of interventions to prevent and/or reduce children's and/or adolescents' problem behaviors. The study reviewed 192 abstracts from journal articles published between the 1986 and June 2006, available on the following databases: Index-Psi/Periódicos, Lilacs, PsycInfo, Scielo and Medline. Categories of analysis focused on bibliography, method, and studies' results. Data-analysis showed that most of the studies focused on groups and families, and samples with more than 30 participants. Study designs were experimental and quasi-experimental, combining observation and self report or just self report for data collection. Result analysis suggests that the intervention programs contributed specially for reducing behavior problems, and improving parental practices. Discussion evaluates contributions of the study and gaps in knowledge.

Sudden cardiac death athletes: a systematic review

Previous events evidence that sudden cardiac death (SCD) in athletes is still a reality and it keeps challenging cardiologists. Considering the importance of SCD in athletes and the requisite for an update of this matter, we endeavored to describe SCD in athletes. The Medline (via PubMed) and SciELO databases were searched using the subject keywords sudden death, athletes and mortality. The incidence of SCD is expected at one case for each 200,000 young athletes per year. Overall it is resulted of complex dealings of factors such as arrhythmogenic substrate, regulator and triggers factors. In great part of deaths caused by heart disease in athletes younger than 35 years old investigations evidence cardiac congenital abnormalities. Athletes above 35 years old possibly die due to impairments of coronary heart disease, frequently caused by atherosclerosis. Myocardial ischemia and myocardial infarction are responsible for the most cases of SCD above this age (80%). Pre-participatory athletes' evaluation helps to recognize situations that may put the athlete's life in risk including cardiovascular diseases. In summary, cardiologic examinations of athletes' pre-competition routine is an important way to minimize the risk of SCD. © 2010 Ferreira et al; licensee BioMed Central Ltd.

Reactores aeróbios de lecho fluidizado trifásico con circulación interna: Caracterización hidrodinámica y del soporte

Aerobic internal-loop reactors use active biomass attached in a supporting media (biofilm) with the advantage of retaining a big biomass concentration in a small physical space, removing carbonaceous matter and nitrogen in only one reactor. Liquid circulation occurs due to hydrostatic pressure difference produced by air injection in the riser. In biphasic conditions liquid circulation velocities, gas holdup and oxygen transfer coefficient in four different reactor configurations were studied. For the three-phase conditions, the same parameters in just one of those configurations were evaluated. Also, there were three granular supporting media characterized. On the other hand, the relationship between internal and external tube areas and supporting media concentrations influence the liquid velocity, gas holdup and oxygen mass transfer values and some important supporting media characteristics were observed and compared.

Fisioterapia no tratamento da dor orofacial de pacientes com disfunção temporomandibular crônica

Recent studies have shown consistent results using the physical therapy in cases of pain and limitation of movement from temporomandibular dysfunction. Thus, our objective was to assess the effect of ten sessions of physical therapy and laser therapy in treatment of muscular pain and arthralgias in a woman with temporomandibular dysfunction. The painful symptoms relief achieved by session was over 20 %, up to zero at the end of treatment. Results demonstrated that the treatment protocol used was effective to reduce the temporomandibular joint and the masseter muscle tension and a decreased of drugs by patient. However, more studies are needed to define with more accuracy the effect of other physiotherapy programs and its interaction with other treatment modalities.