La respiracion normal involucra la utilizacion adecuada del tracto nasal y nasofaringeo. Un aumento de volumen de las estructuras que se encuentran dentro de esos espacios, imposibilita el paso de aire por estos conductos, y el resultado sera que el nino respire por la boca, trayendo serias alteraciones en el aparato estomatognatico que afectan al nino de forma estetica, funcional y psiquicamente. Se realizo un estudio descriptivo transversal, con el objetivo de caracterizar clinica y epidemiologicamente la respiracion bucal en ninos de 3 a 5 anos en la parroquia Catia La Mar, de enero a junio de 2008. El universo estuvo constituido por 350 ninos, y la muestra la conformaron 100 ninos que practicaban el habito de respirador bucal. El habito de respirador bucal se observo en los ninos de menor edad con mayor frecuencia en el sexo masculino. La respiracion bucal patologica predomino sobre la respiracion bucal por habito en los varones. El asma bronquial y la bronquitis asmatica predominaron en las edades de 3 y 5 anos; el mas afectado fue el sexo masculino, mientras que en las hembras predomino la rinitis alergica en la edad de 5 anos. Los pacientes con obstruccion de las vias respiratorias fueron respiradores bucales, y predomino la hipertrofia adenoidea y/o amigdalar y la hipertrofia de cornetes para las hembras y la desviacion del tabique para los varones.
Abstract : A Type I check test of the Tropical Combat Boot, DMS, Spike-Resistant, Man's Leather and Nylon Duck, was conducted. The test was to determine whether shortcomings found during the previous four-month engineering and service test of the tropical combat boot, conducted by USATTC had been corrected satisfactorily. It was concluded that shortening of the shank reduced the incidence of outsole cracking at the flex point but did not reduce the incidence of steel sole plate cracking; that the sole and heel bond to the upper and the knit of the heel to the sole are adequate and durable; and that the difference in the support afforded the ankle is not statistically significant in comparison with that provided by the previously tested boot.
The N2 analogue phosphorus nitride (PN) was the first phosphorus containing compound to be detected in the interstellar medium, however this thermodynamically unstable compound has a fleeting existence on Earth. Here, we show that reductive coupling of iron(IV) nitride and molybdenum(VI) phosphide complexes assembles PN as a bridging ligand in a structurally-characterized bimetallic complex. Reaction with C≡N<sup>t</sup>Bu releases the mononuclear complex [(N<sub>3</sub>N)Mo-PN]<sup>−</sup>, N<sub>3</sub>N = [(Me<sub>3</sub>SiNCH<sub>2</sub>CH<sub>2</sub>)<sub>3</sub>N]<sup>3−</sup>), which undergoes light-induced linkage isomerization to provide [(N<sub>3</sub>N)Mo-NP]<sup>−</sup>, as revealed by photocrystallography. While structural and spectroscopic characterization, supported by electronic structure calculations reveal PN multiple bond character, coordination to molybdenum creates nucleophilic character at the terminal atom of the PN/NP ligands. Indeed, the linkage isomers can be trapped in solution by reaction with a Rh(I) electrophile.
