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The purification of reclaimed water is essential to water reclamation technology life-support systems in lunar/Mars habitats. An electrochemical UV reactor is being developed which generates oxidants, operates at low temperatures, and requires no chemical expendables. The reactor is the basis for an advanced oxidation process in which electrochemically generated ozone and hydrogen peroxide are used in combination with ultraviolet light irradiation to produce hydroxyl radicals. Results from this process are presented which demonstrate concept feasibility for removal of organic impurities and disinfection of water for potable and hygiene reuse. Power, size requirements, Faradaic efficiency, and process reaction kinetics are discussed. At the completion of this development effort the reactor system will be installed in JSC's regenerative water recovery test facility for evaluation to compare this technique with other candidate processes.

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Correspondio a Chile ser el primer pais latinoamericano en iniciar relaciones directas con la Santa Sede producida que fue la independencia de los paises que habian formado parte de la monarquia espanola, contactos que dieron origen a la primera mision diplomatica enviada por la Santa Sede a los paises recientemente independizados, presidida por Giovanni Muzi y en la que venia el entonces joven monsenor Giovanni Maria Mastai Ferreti quien, con el tiempo ocuparia el trono pontificio con el nombre de Pio IX. A partir de ese momento, los contactos entre la Santa Sede y los paises latinoamericanos se multiplicaron y desde 1851 empezaron a suscribirse distintos concordatos, siendo el primero de ellos el celebrado con Bolivia el que, aunque no fue ratificado por el Congreso de ese pais, sirvio de modelo a los primeros concordatos que se firmaron en anos sucesivos: Costa Rica (1852), Guatemala I (1852), Haiti (1860), Honduras (1861), Nicaragua (1861), Ecuador I (1862), El Salvador (1862), Venezuela (1862), Ecuador II (1881), Guatemala II (1884) y Colombia (1887, 1891), sin perjuicio de algunos acuerdos sobre materias especificas y la bula de concesion del derecho de patronato al Presidente del Peru. La mayor parte de ellos, sin embargo, tuvo una vida efimera.

INTRODUCCIÓN: el objetivo de este estudio in vitro fue comparar el grado de transportación de los canales radiculares utilizando tres técnicas de instrumentación rotatoria: HERO Shaper, ProTaper Universal y RaCe. MÉTODOS:se seleccionó una muestra de treinta canales vestibulares de molares humanos superiores con ángulo de curvatura entre 25 y 35° con conductos finos y formación radicular completa que fue dividida en tres grupos arbitrarios de diez conductos cada uno, los que fueron preparados por los sistemas de instrumentación rotatoria HERO Shaper, ProTaper Universal y Race respectivamente, todos hasta el diámetro # 30 a la longitud de trabajo, utilizando el motor Endo-Mate TC NSK con control de torque y velocidad controlada. Se tomaron radiografías previas y posteriores a la instrumentación, las que fueron digitalizadas con escáner Agfa Duoscan T1200 a resolución de 2.400 dpi en escala de grises, luego mediante el método de morfometría lineal utilizando el sistema computacional para imágenes digitales NIH ImageJ se hicieron un total de 12 mediciones por canal, 4 para el ancho total radicular, 4 para la pared cóncava y 4 para la pared convexa, todos a 1, 2, 4 y 6 mm, respectivamente, desde el vértice radiográfico del conducto. Los datos obtenidos fueron analizados mediante eálisis estadístico no paramétrico Mann Whitney Rank Sum y Kruskal Wallis para muestras independientes. RESULTADOS: se observa transportación del canal radicular hacia la pared cóncava al utilizar el sistema ProTaper Universal, siendo estadísticamente significativa. (p = 0,01). CONCLUSIÓN: el sistema rotatorio ProTaper Universal produce mayor número de transportaciones al compararlo con los sistemas RaCe y HERO Shaper.INTRODUCTION:the objective of this in vitro study was to compare the degree of transportation of root canals using three rotary systems: HERO Shaper, ProTaper Universal, and Race. METHODS:a sample of thirty buccal root canals of upper molars with curvatures between 25 and 35° was divided into three random groups of ten canals each, which were then instrumented by using the rotary systems HERO Shaper, ProTaper Universal, and Race respectively, all to a diameter # 30 to the working length, using the motor NSK Endo-Mate TC to control torque and speed. Radiographs were taken before and after mechanical instrumentation, and they were scanned with DuoScan Agfa T1200 scanner at a resolution of 2400 dpi gray scale. Afterwards, by the method of lineal morphometry and using the computer system for digital images NIH imageJ, a total of 12 measurements per root canal were done: 4 for the total root width, 4 for the concave wall and 4 for the convex wall, all at 1, 2, 4 and 6 mm respectively from the radiographic apex of the canal. The data were analyzed by using the Mann Whitney Rank Sum and Kruskal Wallis nonparametric statistical analysis for independent samples. RESULTS:Transportation was observed from the root canal to the concave wall when the ProTaper Universal system was used, being statistically significant (p = 0,01). CONCLUSION:the ProTaper Universal rotary system produced the greatest number of transportations when compared with HERO Shaper and RaCe systems.

Objective: This study uses polysomnography and the Epworth sleepiness scale to assess the efficiency of the Ocluch©MAD in patients with Obstructive sleep apnea-hypopnea syndrome (OSAS), on overall respiratory disturbance indices (RDI), supine respiratory disturbance index (SRDI), minimum oxygen saturation, microarousals, CT90 (or ID90), sleep efficacy and snoring. These data are associated with skeletal class and facial biotype in order to establish predictive parameters for its effectiveness according to craniofacial morphology. Methods: 22 adult patients (between 38 and 60 years of age) of both sexes (7 women, 15 men) diagnosed with OSAS in the Hospital de Carabineros de Chile (HOSCAR) Neurology Unit were recruited and given the Ocluch© MAD in the hospital’s dental clinic, for its use during a three-month period. Patients were assess at the beginning and in the end of this period. Results: 87.5% of patients with mild OSAS achieved the success criterion and normalization; 71.5% of patients with moderate OSAS achieved the success criterion and 33.3% achieved normalization; 85.7% of patients with severe OSAS achieved the success criterion and 57.1% achieved normalization. All class I and mesofacial patients achieved normalization, but class II patients had the greatest proportional improvement. Conclusions: The Ocluch MAD is an efficient low-cost alternative that should be considered among the therapeutic arsenal for a multidisciplinary approach to treating this disease.

ObjectivesThe aim of this study was to evaluate right ventricular (RV) and left ventricular function and pulmonary circulation in chronic mountain sickness (CMS) patients with rest and stress echocardiography compared with healthy high-altitude (HA) dwellers.BackgroundCMS or Monge's disease is defined by excessive erythrocytosis (hemoglobin >21 g/dl in males, 19 g/dl in females) and severe hypoxemia. In some cases, a moderate or severe increase in pulmonary pressure is present, suggesting a similar pathogenesis of pulmonary hypertension.MethodsIn La Paz (Bolivia, 3,600 m sea level), 46 CMS patients and 40 HA dwellers of similar age were evaluated at rest and during semisupine bicycle exercise. Pulmonary artery pressure (PAP), pulmonary vascular resistance, and cardiac function were estimated by Doppler echocardiography.ResultsCompared with HA dwellers, CMS patients showed RV dilation at rest (RV mid diameter: 36 ± 5 mm vs. 32 ± 4 mm, CMS vs. HA, p = 0.001) and reduced RV fractional area change both at rest (35 ± 9% vs. 43 ± 9%, p = 0.002) and during exercise (36 ± 9% vs. 43 ± 8%, CMS vs. HA, p = 0.005). The RV systolic longitudinal function (RV-S′) decreased in CMS patients, whereas it increased in the control patients (p

Wood drying is an important process for adding value and manufacturing innovative products. Eucalyptus nitens wood is inherently difficult to dry because of its natural propensity for checking as well as collapse and shrinkage. Lumber recovery after industrial drying of eucalypts is also very low. This study measured the wood quality of E. nitens juvenile wood (13 mm thickness) after radio-frequency vacuum (RFV) drying and wood dried in a conventional kiln dryer (KD). Drying cycles were performed using a radio frequency vacuum dryer with a 3 m3 of capacity and convective kiln-dryer equipment with a 3.5 m3 of capacity. The results showed that the drying time using the radio frequency vacuum method was reduced by 47% when compared to conventional kiln drying. The shrinkage was significantly lower in the RFV than in the conventional KD. The volumetric collapse decreased by approximately 60% in the RFV drying. RFV drying of E. nitens juvenile wood improves the wood quality for solid wood products because the intensity of surface checking and collapse are reduced.