Prevalence of Geographic Tongue in Chilean Children between 7 and 10 Years of Age

Indexación: Web of Science; Scielo.RESUMEN: El objetivo del estudio fue determinar la prevalencia de lengua geográfica y evaluar su asociación con el estrés emocional, irritación crónica, lengua fisurada y tipo de establecimiento educacional, en niños de 7 a 10 años de edad en la ciudad de Viña del Mar, Chile. De un total de 27.234 escolares, cursando 2 a 5 año básico, pertenecientes a colegios de la ciudad de Viña del Mar, Chile, se examinaron 436 niños.Se realizó un estudio descriptivo transversal de alumnos provenientes de tres tipos de establecimientos educacionales diferentes: particular, particular con subvención del estado de Chile y municipalizado. Las variables estudiadas fueron edad, sexo y establecimiento educacional. Adicionalmente, en los alumnos con lengua geográfica y 23 alumnos sin este diagnóstico se evaluó la presencia de lengua fisurada, irritación lingual crónica y estrés emocional. Se determinó la prevalencia mediante el cálculo de una proporción, las variables discretas se analizaron mediante Chi-cuadrado de Pearson o la prueba de Fisher y para determinar medidas de asociación con lengua geográfica se realizó regresión logística binaria, considerándose significativo un p<0,05. De los 436 niños, 23 presentaron lengua geográfica, evidenciando una prevalencia de 5,28%, con un IC 95% de 3,37% a 7,81%. No se evidenciaron diferencias respecto al sexo, edad ni tipo de establecimiento educacional. No se determinaron factores asociados a lengua geográfica. La prevalencia de LG determinada es similar a otros estudios que abarcan la misma población de rangos etarios. Al igual que en otros estudios no se pudo demostrar que el estrés emocional, irritación crónica, lengua fisurada y tipo de establecimiento educacional constituyeron factores asociados a la presencia de lengua geográfica.ABSTRACT: The aim of this study was to determine the prevalence of geographic tongue and evaluate its association with emotional stress, chronic irritation, fissured tongue and type of educational establishment, in children between 7 and 10 years of age, in the city of Viña del Mar, Chile. From a total of 27,234 students attending 2nd through 5th grade, we examined 436 children. A descriptive study of students was carried out from three different educational institutions: private, private with state funding and public schools. The variables studied were age, sex and the educational establishment the children attended. Additionally in the students with geographic tongue and in 23 students without this diagnosis, we evaluated the presence of fissured tongue, tongue irritation and chronic emotional stress. Prevalence was determined by calculating ratio, discrete variables were analyzed using Pearson Chi-square test or Fisher, and in order to determine association measures with geographic tongue, binary logistic regression was considered significant at p <0.05. Of the 436 children, 23 had geographic tongue, showing a prevalence of 5.28% with a 95% CI 3.37% to 7.81%. No differences regarding sex, age and type of educational establishment were found. No factors associated with geographic tongue were determined. The prevalence of the LG is similar to other studies covering the same age ranges. Furthermore, and as in other works, our study did not to show that emotional stress, chronic irritation, fissured tongue and the type of educational establishment constituted factors associated with the presence of geographic tongue.http://ref.scielo.org/y3rcd

Determining fundamental parameters from the chargino sector in Left-Right Supersymmetric models

Analytical expressions relating the fundamental parameters describing the chargino sector in the context of the Left-Right Supersymmetric model are constructed. A general complex extension of the real non-symmetric chargino mass matrix including all possible CP-violating phases is considered. The method used for such a effects is the projector formalism based on the explicit knowledge of two unitary matrices diagonalizing the chargino mass matrix. Some possible scenarios allowing us to extract analytical and numerical values for the unknown parameters are considered. Moreover, an algorithm allowing us to disentangle the fundamental parameters of the chargino sector, based on possible measurements of some class of cross-section observables related to the chargino pair production in $e^+ e^-$ annihilation processes, is described. Some comparisons with the corresponding results in the context of the Minimal Supersymmetric Standard Model are given.Comment: 48 pages, 13 figure

Role of Astroglial Hemichannels and Pannexons in Memory and Neurodegenerative Diseases

Indexación: Web of ScienceUnder physiological conditions, astroglial hemichannels and pannexons allow the release of gliotransmitters from astrocytes. These gliotransmitters are critical in modulating synaptic transmission, plasticity and memory. However, recent evidence suggests that under pathological conditions, they may be central in the development of various neurodegenerative diseases. Here we review current literature on the role of astroglial hemichannels and pannexons in memory, stress and the development of neurodegenerative diseases, and propose that they are not only crucial for normal brain function, including memory, but also a potential target for the treatment of neurodegenerative diseaseshttp://journal.frontiersin.org/article/10.3389/fnint.2016.00026/ful

The Adverse Effects of Environmental Policy in Green Markets

We model green markets in which purchasers, either firms or consumers, have higher willingness-to-pay for less polluting goods. The effectiveness of pollution reduction policies is examined in a duopoly setting. We show that duopolists´ strategic behaviour may increase pollution levels. Maximum emission standards, commonly used in green markets, improve the environmental features of products. Nonetheless, overall pollution levels will rise because government regulation also affects market shares and boosts firms´ sales. Consequently, social welfare may be reduced. We also explore the effects of technological subsidies and product charges, including differentiation of charges.emission standards; subsidies; product charges; vertically differentiated duopoly

Linear Model-Based Predictive Control of the LHC 1.8 K Cryogenic Loop

The LHC accelerator will employ 1800 superconducting magnets (for guidance and focusing of the particle beams) in a pressurized superfluid helium bath at 1.9 K. This temperature is a severely constrained control parameter in order to avoid the transition from the superconducting to the normal state. Cryogenic processes are difficult to regulate due to their highly non-linear physical parameters (heat capacity, thermal conductance, etc.) and undesirable peculiarities like non self-regulating process, inverse response and variable dead time. To reduce the requirements on either temperature sensor or cryogenic system performance, various control strategies have been investigated on a reduced-scale LHC prototype built at CERN (String Test). Model Based Predictive Control (MBPC) is a regulation algorithm based on the explicit use of a process model to forecast the plant output over a certain prediction horizon. This predicted controlled variable is used in an on-line optimization procedure that minimizes an appropriate cost function to determine the manipulated variable. One of the main characteristics of the MBPC is that it can easily incorporate process constraints; therefore the regulation band amplitude can be substantially reduced and optimally placed. An MBPC controller has completed a run where performance and robustness has been compared against a standard PI controller (Proportional and Integral)

Sex steroid hormones and brain function:PET imaging as a tool for research

Sex steroid hormones are major regulators of sexual characteristic among species. These hormones, however, are also produced in the brain. Steroidal hormone-mediated signalling via the corresponding hormone receptors can influence brain function at the cellular level and thus affect behaviour and higher brain functions. Altered steroid hormone signalling has been associated with psychiatric disorders, such as anxiety and depression. Neurosteroids are also considered to have a neuroprotective effect in neurodegenerative diseases. So far, the role of steroid hormone receptors in physiological and pathological conditions has mainly been investigated post mortem on animal or human brain tissues. To study the dynamic interplay between sex steroids, their receptors, brain function and behaviour in psychiatric and neurological disorders in a longitudinal manner, however, non-invasive techniques are needed. Positron emission tomography (PET) is a non-invasive imaging tool that is used to quantitatively investigate a variety of physiological and biochemical parameters in vivo. PET uses radiotracers aimed at a specific target (eg, receptor, enzyme, transporter) to visualise the processes of interest. In this review, we discuss the current status of the use of PET imaging for studying sex steroid hormones in the brain. So far, PET has mainly been investigated as a tool to measure (changes in) sex hormone receptor expression in the brain, to measure a key enzyme in the steroid synthesis pathway (aromatase) and to evaluate the effects of hormonal treatment by imaging specific downstream processes in the brain. Although validated radiotracers for a number of targets are still warranted, PET can already be a useful technique for steroid hormone research and facilitate the translation of interesting findings in animal studies to clinical trials in patients

Synthesis, characterization, and purification of boron nitride nanotubes intercalated with magnesium

Intercalation of Boron Nitride Nanotubes (BNNTs) with magnesium (Mg) is explored due to its potential super-conductive properties. Various syntheses were performed under different sets of conditions in order to optimize reaction conditions. These include the presence of zinc as a catalyst and the temperature at which the reaction is carried out (either 700 or 800°C). All products were then analyzed and characterized, using methods such as Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray Spectroscopy (EDX), and Fourier-Transform Infrared Spectroscopy (FTIR). Both TEM and FTIR results confirmed the formation of BNNTs, and EDX showed the presence of magnesium in the product, indicating possible intercalation with Mg. A purification method for the crude product was established, and the purified product was further characterized. Results indicated the tubes became clearer after purification, however, some impurities remain. Purification methods must be further investigated.B.S. (Bachelor of Science