ABSTRACT: Aim: To compare the hydraulic conductance of human dentin disks which have been treated with an adhesive by operators of different genders and by active or passive modes of application. 60 third molars of healthy adults were included in resin blocks. These were cut to obtain 60 dentin disks of 1mm +/- 0.1 mm thick. Group 1 and 2, the adhesive was applied by 15 male operators passively (group 1) and vigorously (group 2). Groups 3 and 4, the adhesive was applied by 15 female operators passively (group 3) and vigorously (group 4). The flow rate was measured with a diffusion chamber and the hydraulic conductance of the disks was determined. Results: Mean for hydraulic conductance of each group was: 1 (0.01752), 2 (0.00355), 3 (0.01215), 4 (0.00877) in μl/minxcm2. There was statistically significant difference in the hydraulic conductance between experimental and control groups. There was no difference in dentin hydraulic conductance between genders. There was statistically significant difference in hydraulic conductance between the different modes of application. There was a moderate association between the pressure exerted when applying the adhesive and the values of dentin hydraulic conductance in vitro.

Background: Anti-thyroid peroxidase antibodies have a pathogenic role in Hashimoto thyroiditis. Between 10 and 19% of individuals without thyroid disease, have positive titers of these antibodies. Aim: To study the frequency of positive titers of anti-thyroid peroxidase antibodies in healthy individuals. Material and Methods: A blood sample, to measure anti-thyroid peroxidase antibodies and thyroid stimulating hormone (TSH) by chemoluminiscense assay, was obtained from 67women and 62 men aged 45 ± 14years, without a personal or familiar history of thyroid diseases and normal thyroid palpation. The cutoff point of the manufacturer to consider positive a titer of anti-thyroid peroxidase antibodies was set at 35 IU/ml. Results: Twenty-eight women and 28 men had positive antibody titers (43% of the sample). Subjects in the upper tercile of anti-thyroid peroxidase antibody titers had a higher TSH than those in the second tercile, although within normal limits (1.73 ± 0.74 and 1.37 ± 0.59 mlU/L, respectively p = 0.02) Conclusions: Forty three percent of the studied subjects without personal or familial history of thyroid diseases had positive titers of anti-thyroid peroxidase antibodies. Further prospective studies should evaluate whether this observation discloses an increase in thyroid autoimmune disease in a population with increased iodine intake.

A total of 126 sword-fish (Xiphias gladius) stomach were analyzed. The stomachs were obtained from specimens captured within the 25° to 34°S and 78° to 90°W área, by industrial longline vessels. Only 72 (57.1%) of the total stomach had food ítems in their stomachs, whit a sex proportion of 32 males (44.4%o), 37 females (51.4%) and 3 indeterminate (4.2%). Traditional methods for the stomach contents analysis such as the numeric, frequency of occurrence, gravimetric and índex of relative importance (IRI) were used. Cephalopods were the main food ítems (%IIR > 90) followed by the fishes (%IIR < 4). The squid (Dosidicus gigas) was the principal food in this study (%IIR = 85.1). No significant differences were found between the feeding of males and females of swordfishes (U = 81; p = 0.4862, p < 0.05). A cluster analysis showed higher stomach contents similarity between fall and winter than those from spring, within the size groups the I group was different than others and finally, the feeding from zone 3 were different from others zones.

Se analizaron 126 estómagos de pez espada (Xiphias gladius), capturados entre los 25° y 34°S y 78° y 90°W, por barcos palangreros de la pesquería industrial frente a Chile centro-norte. Del total de estómagos analizados, 54 se encontraron vacíos (42,9%) y 72 (57,1%) presentaron sus estómagos con contenidos, de estos últimos la proporción sexual correspondió a 32 machos (44,4%), 37 hembras (51,4%o) y 3 indeterminados (4,2%o). Para el análisis de contenidos estomacales se utilizaron los métodos numéricos, de frecuencia, gravimétricos e índice de importancia relativa (IIR). Los cefalópodos fueron el alimento principal (%IIR > 90), mientras que los peces aparecen como alimento secundario (%IIR < 4). El cefalópodo Dosidicus gigas fue la presa principal (%IIR = 85,1). No se encontró diferencia significativa entre la alimentación por sexos ({/= 81; p = 0,4862, p < 0,05). Los análisis de conglomerados revelaron que los contenidos estomacales son más similares en otoño e invierno que en primavera; mientras que entre los distintos grupos de tallas el grupo I aparece como distinto del resto de las tallas, y los estómagos analizados provenientes de la zona 3 serían más diferentes que el resto de las áreas estudiadas.

The ex situ culture by spores of Pteris chilensis Desv. is presented. The germination of spores occurred after 10-12 days, having the pattern of germination as Vittaria type. A filamentous gametophyte of 3-4 cells is formed after 23-24 days; reaching the mature developing between 60-95 days. The cordiform gametophyte shows two symmetrical wings. The archegonia appear before the antheridia. Finally, the first frond is formed after 115 days of sowing. The spores are cultured in agar on Thompson nutritive medium in a culture chamber at a photoperiod of 12 hours light (1,500 lux) and a mean temperature of 25°C

El cultivo ex situ de Pteris chilensis Desv. a partir de esporas es presentado. La germinación de las esporas ocurre a los 10-12 días y el patrón de germinación es del tipo Vittaria. Un gametófito filamentoso de 3-4 células es obtenido a los 23-24 días, logrando su desarrollo adulto entre los 60 a 95 días. Este se caracteriza por ser cordiforme y con alas simétricas. Los arquegonios se forman antes que los anteridios. Finalmente, la primera fronde aparece a los 115 días de sembradas las esporas. Las esporas se cultivaron en agar con medio nutritivo de Thompson, en cámara de cultivo con un fotoperíodo de 12 horas luz (1.500 lux) y una temperatura promedio de 25°C

Discutimos a importância das soluções exatas das equações de Einstein no desenvolvimento da relatividade geral, em particular as soluções com simetria axial. Apresentamos um resumo da teoria da gravitação newtoniana colocando ênfase nas soluções exatas da equação de Poisson, em particular a geração de soluções que representam discos, sendo também o critério de estabilidade de Rayleigh discutido neste contexto. Fazemos um resumo da teoria da gravitação de Einstein e apresentamos a solução de Weyl que representa o campo gravitacional de um corpo com simetria axial. A geração de soluções exatas das equações de Einstein que representam o espaço-tempo associado a discos finos, discos grossos e discos com halos é estudada usando uma extensão do método das imagens. Os parâmetros físicos dos discos tais como a densidade, a pressão e a velocidade do som também são analisados em detalhe. A estabilidade de Rayleigh e a estabilidade hidrodinâmica são também estudadas para uma família de discos finos isotrópicos previamente apresentada.

We discuss the relevance of the exact solutions to the Einstein equations in the development of general relativity, in particular the solutions with axial symmetry. We present a summary of the Newtonian gravity theory with emphasis in the generation of solutions to the Poisson equation that represent disks. Also the Rayleigh criterion of stability is discussed in this context. We give a summary of the Einstein theory of gravitation and present the Weyl solution that represent the gravitational field of a body with axial symmetry. The generation of exact solutions to the Einstein equations that describe the space-time associated to thin disks, thick disks and disks with halos is studied using an extention of the image method. The physical parameters of the disks such as, density, pressure, sound velocity are also analyzed in detail. Furthermore, both the Rayleigh stability and hydrodynamical stability are studied for a family of thin isotopic disks previously studied.