Postural sway in the moving room scenario: New evidence for functional dissociation between self-motion perception and postural control

Postural control in quiet standing is often explained by a reflexive response to optical flow, the apparent motion of environmental objects in a visual scene. However, moving room experiments show that even small-amplitude body sway can evoke odd sensations or motion sickness, indicating that a consciousness factor may also be involved. Studies targeting perception of self-motion, vection, typically use rapid visual stimuli moving in a single direction to maintain a constant feeling of vection, and there are few studies of vection using low-speed sinusoidal visual stimuli similar to human pendular movement. In the present study we searched for changes in postural control during periods of vection during quiet standing. Participants (N = 19, age = 20.4 ±1.1 years) were shown dynamic visual stimuli in the form of sinusoidally expanding and contracting random dots, and the stimuli speed and visual field were manipulated. Posture was continually evaluated using Center of Pressure (CoP) measurements. Participants were also asked to report feelings of vection, both by pressing a button during the trial and through an overall rating at the end of each trial. Using repeated-measures ANOVA, we assessed changes in the CoP and vection variables between experimental conditions, as well as possible interactions between the variables. The results show that postural reaction and vection were both affected by the visual stimuli and varied with speed. The peripheral visual field was found to couple to stronger feeling of vection and better quality of postural control. However, no significant relationship between postural control and vection, nor evidence of vection interaction to the relationship between optical flow and postural control, was found. Based on our results we conclude that for postural stability during quiet standing, visual cues dominate over any potential consciousness factor arising due to vection.

Frequentadores de academias do ramo fitness em condições de pendularidade na fronteira Brasil-Bolívia (Gym goers in the fitness industry in pendularity conditions at the Brazil-Bolivia border)

O presente estudo teve como objetivo principal descrever aspectos gerais sobre os frequentadores (alunos/clientes - praticantes da musculação) de academias brasileiras do ramo fitness e que residem na Bolívia e, ao mesmo tempo, compreender a opinião dos responsáveis (proprietários/responsáveis/professores) desses espaços na cidade de Corumbá-MS (Brasil), especialmente considerando a condição de pendularidade dos usuários na fronteira estudada. Foram mapeadas, exclusivamente, as academias de “livre acesso” (sem treinamento personalizado), bem como que atendesse alunos em condição de pendularidade, praticantes de musculação e que autorizaram o desenvolvimento da pesquisa. Desta forma, a amostra teve duas unidades selecionadas, sendo que foram aplicados questionários com perguntas abertas e fechadas aos dois grupos delimitados (alunos/clientes e proprietários/responsáveis/professores). Os resultados preliminares mostram que a aderência e frequência desses espaços fitness, na visão dos alunos/clientes pendulares, se dá por diferentes motivos, destacando-se a boa localização, preço/qualidade, emagrecimento, manutenção da saúde, treinamento esportivo, enquanto que na visão dos proprietários/responsáveis/professores destacam-se a boa comunicação e a importância no fomento da economia/comércio local. Concluímos, portanto, que por se tratar de uma região fronteiriça, torna-se de extrema importância descrever os aspectos gerais desse público, sobretudo ressaltando os motivos do movimento pendular nesse seguimento fitness. Os resultados, embrionários, também reforçam a necessidade de mais estudos para compreender melhor a frequência e participação desses sujeitos em condição pendular nos diferentes espaços fitness da região. Abstract: The present study had as main objective to describe general aspect the regulars (students/clients - bodybuilding practitioners) of brazilian fitness gyms that reside in Bolivia and, at the same time, to understand the opinion of those responsible (owners/guardians/teachers) of these spaces in the city of Corumbá-MS (Brazil), especially considering the condition of pendularity of users on the studied border. The “free access” gyms (without personalized training) were mapped, as well as that attended students in a condition of pendularity, practitioners of weight training and who authorized the development of the research. In this way, the sample had two units selected, and questionnaires with open and closed questions were applied to the two delimited groups (students/clients and owners/guardians/teachers). Preliminary results show that the adherence and frequency of these fitness spaces, in the view of students/clients pendularity, occurs for different reasons, highlighting the good location, price/quality, weight loss, health maintenance, sports training, while in the view of the owners/guardians/teachers, good communication and importance in fostering the local economy/trade are highlighted. We conclude, therefore, that because it is a border region, it becomes extremely important to describe the general aspect of this audience, especially highlighting the reasons for the pendular movement in this fitness segment. The embryonic results also reinforce the need for further studies to better understand the frequency and participation of these subjects in pendulum condition in the different fitness spaces in the region.

A filosofia como matéria de ensino no Brasil: gênese e atualidade dos processos históricos

O ensino da filosofia se destaca como parte a ser reconhecida nos processos históricos de organização da educação no Brasil pela força dos interesses políticos que se encontram atravessados desde os primeiros traços da pedagogia catequética jesuítica. Por essa razão, propomos, neste texto, revisitar a história da educação brasileira para compreender o movimento pendular de inclusão e exclusão da filosofia como matéria de ensino, analisar as razões ideológicas que justificam este movimento, e, por fim, evidenciar os contornos e as formas teóricas próprias que modificaram suas características enquanto disciplina do currículo escolar. Para tanto, buscamos apoio teórico em Ceppas (2010), Cartolano (1985), Gallo e Kohan (2000) e Saviani (2010). Trata-se de uma discussão que se desdobra nos entremeios das narrativas históricas da educação brasileira, e que nos permite não só identificar os movimentos de inclusão e exclusão da filosofia nos programas educacionais a partir do século XVI, mas, sobretudo, colocar em questão o modo como esses interesses políticos forjaram os diferentes ideais de homem e sociedade dos quais somos herdeiros.Palavras-chave: História; Filosofia; Currículo; Ensino. ABSTRACT: The teaching of philosophy highligts as part to be recognized in the historical processes of educational organization in Brazil by the force of political interests that have been crossed since the first traits of jesuit catechetical pedagogy. For this reason, we propose, in this text, to revisit the history of brazilian education to compreend the pendular movement of inclusion and exclusion of philosophy as a teaching subject, analyzing the ideological reasons that justify this movement, and, at the end, highlights the contourns and theorical ways that modifiered this characteristics while subject in the school curriculum. For this, we seek theoretical support in Ceppas (2010), Cartolano (1985), Gallo and Kohan (2000) and Saviani (2010). It is a discussion that unfolds in the intertwining of historical narratives of Brazilian education, and that allows us not only to identify the movements of inclusion and exclusion of philosophy in educational programs from the sixteenth century, but above all to question how these political interests forged the different ideals of man and society from which we are heirs.Keywords: History; Philosophy; Curriculum; Teaching.

Intestine motility, secretion, and constipation treatment principles

Introduction. Constipation is a derangement of the motor, secretory and/or evacuation function of the colon. The same symptoms are recorded in at least 20% of the population in the developed countries – as those occurring sporadically or for a long period.Basic content. The secretory function of the colon significantly affects stool consistency and its free movement. The secretion increases by 8–10 times in the presence of local mechanical irritation. Intestinal mucus is produced by colonic goblet cells. The frequency, time of defecation and stool consistency is in large part determined by the motor function of the colon. The relation of various types of contraction varies depending on the main function – propulsion or mixing. Rhythmic phasic contractions in the colon generate a pendular movement with slow propulsion of the contents and absorption of water. The tonic contractions enhance the mixing effect of weak rhythmic contractions. The propulsive contractions are specifically attributed to the lower gastrointestinal tract and occur spontaneously. They occur quite regularly, from 2 to 10 times a day, and ensure the propulsion of intestinal contents over great distances in the colon. When reaching the sphincter area, such wave causes its relaxation by mechanisms of descending inhibition. The dietary regime and adequate intake of carbohydrates with various chain lengths, including dietary fiber, as well as flavonoids and other components that modify peristaltic activity and secretion, play an important role in the regulation of intestinal secretion and peristalsis. The drugs enhancing intestinal secretion and peristalsis, such as bisacodyl and sodium picosulfate, are also used to treat constipation. These substances hydrolyse into bis-(p-hydroxyphenyl)-pyridyl-2-methane in the intestine, which, upon contact with the receptors in colonic mucosa, stimulates propulsive activity and increases intestinal secretion. The selective action of sodium picosulfate is confined to the colon.Conclusion. Pharmacological and non-pharmacological treatments for constipation are aimed at maintaining and enhancing the natural propulsive contractions of the colon and intestinal secretion.

Contractions transport exfoliated epithelial cells through the neonatal epididymis

Contractions of the adult epididymal duct are well known in the context of sperm transport. Some reports also describe contractions of the epididymal duct during development, but data about their character, regulation and function are sparse. In the foetal human epididymis we found luminal cells and could identify them as exfoliated epithelial cells originating from the epididymis and not from testis by using antibodies against neutral endopeptidase as an epithelial epididymal duct marker. Exfoliated cells were also found in the epididymal duct after birth. Time-lapse imaging revealed directional transport of luminal cells in the neonatal rat epididymis interrupted by pendular movement. Spontaneous contractions were discovered in the neonatal epididymis and an association between these contractions and the transport of the luminal cells could be observed. Both, transport and spontaneous contractions, were affected significantly by substances known to contract (noradrenaline) or relax (the phosphodiesterase 5 inhibitor sildenafil) smooth muscle cells. Immunohistochemistry showed staining for the proliferation marker proliferating-cell-nuclear-antigen (PCNA) in cells of the ductal lumen of the neonatal rat epididymis indicating the extrusion of cells also during proliferation. Our data showed spontaneous contractions of the immature epididymal duct associated with the transport of exfoliated luminal cells before the first occurrence of sperm cells. Results suggest an important role including both (i) a mechanical place holder function of exfoliated luminal cells (ii) together with a novel idea of organized waste disposal of these cells during development.

Computer-Aided Design and Kinematic Simulation of Huygens’s Pendulum Clock

This article presents both the three-dimensional modelling of the isochronous pendulum clock and the simulation of its movement, as designed by the Dutch physicist, mathematician, and astronomer Christiaan Huygens, and published in 1673. This invention was chosen for this research not only due to the major technological advance that it represented as the first reliable meter of time, but also for its historical interest, since this timepiece embodied the theory of pendular movement enunciated by Huygens, which remains in force today. This 3D modelling is based on the information provided in the only plan of assembly found as an illustration in the book Horologium Oscillatorium, whereby each of its pieces has been sized and modelled, its final assembly has been carried out, and its operation has been correctly verified by means of CATIA V5 software. Likewise, the kinematic simulation of the pendulum has been carried out, following the approximation of the string by a simple chain of seven links as a composite pendulum. The results have demonstrated the exactitude of the clock.

Kinematic Locomotion Changes in C57BL/6 Mice Infected with Toxoplasma Strain ME49

Chronic infection with the intracellular parasite Toxoplasma gondii produces an accumulation of cysts in the brain and muscle, causing tissue damage. The cysts in the brain motor regions affect some kinematic locomotion parameters in the host. To localize the brain cysts from Toxoplasma gondii and study the changes in kinematic locomotion in C57BL/6 mice. Female adult C57BL/6 mice were infected orally with 30 ME-49 Toxoplasma gondii cysts. An uninfected group (n = 7) and two infected groups, examined 15 and 40 days postinfection, were used for this study. To evaluate kinematic locomotion, the mice were marked with indelible ink on the iliac crest, hip, knee, ankle, and phalangeal metatarsus of the left and right hindlimbs. At least three recordings were carried out to obtain videos of the left and right hindlimbs. Mice were video recorded at 90 fps at a resolution of 640 × 480 pixels while walking freely in a transparent Plexiglass tunnel. We measured the hindlimb pendular movement and the hindlimb transfer [linear displacement] curves for each step and evaluated them statistically with Fréchet dissimilarity tests. Afterward, the mice were sacrificed, and the brain, heart, skeletal muscle, lung, liver, and kidney were obtained. The different tissues were stained with hematoxylin and eosin for analysis with optical microscopy. Topographic localization of the cysts was made using bregma coordinates for the mouse brain. The cysts were distributed in several brain regions. In one mouse, cyst accumulation occurred in the hippocampus, coinciding with an alteration in foot displacement. The step length was different among the different studied groups.

O movimento histórico: produto da (des)razão. Um ensaio sobre a filosofia católica da história (1800-1960)

Este texto propõe um esboço de interpretação das “causas” do movimento histórico, tendo como suporte um estudo das posições assumidas pelo iluminismo, positivismo, marxismo e, em particular, pelo catolicismo sobre o tema, demonstrando como todas essas tendências filosóficas e políticas vinculavam estreitamente o movimento da história à teoria do conhecimento. Como desdobramento, esboça também uma interpretação sobre a qualidade desse movimento, dando ênfase à tese do movimento pendular que freqüenta a filosofia da história do catolicismo conservador no período indicado.Abstract: Based on a study of the positions adopted by the Enlightenment, by Positivism, by Marxism and, in particular, by Catholicism on this specific issue, this text attempts to give a brief interpretation of the “causes” for the historical movement. It hopes to demonstrate how all of these philosophical and political trends closely linked the movement of history to the theory of knowledge. As a secondary theme, it also outlines an interpretation of the quality of this movement, focusing in particular on the thesis of the pendular movement that is commonly found in the philosophy of history of conservative Catholicism in the period under study.