La ontogenia se basó en 30 embriones y 30 larvas, obtenidos mediante la inducción del desove de reproductores provenientes de la ribera del río Usumacinta en Tenosique, Tabasco, México, recolectados en febrero de 2009. La descripción se fundamentó en el registro morfométrico y merístico. Los huevos fueron recuperados en estado de gástrula y presentaron un diámetro de promedio de 1.17mm (SD=0.08). Durante las primeras tres horas de desarrollo embrionario, se presentó la etapa de capullo, en la que se observó la región caudal adherida al vitelo, apreciándose la vesícula de Kupffer. Las larvas con saco eclosionaron a las 18 horas pos-fertilización, fueron de color marrón claro con un promedio de 2.94mm; (SD=0.70) de longitud total y alcanzaron la preflexión a los ocho días post-eclosión con una longitud total promedio de 4.67mm; (SD=0.50) y una longitud total del notocordio de 4.45; (SD=0.50). A los 16 días de la eclosión alcanzaron la flexión, con un promedio de 6.66mm; (SD=1.53) de longitud total. La postflexión se presentó a los 24 días con 10.33mm; (SD=1.45). Al llegar a los 33 días, se presentó la fase prejuvenil y llegaron a medir 14.30; (SD=0.93) de longitud total, presentando IX espinas y 10 radios en la aleta dorsal y III y ocho en la aleta anal. Los juveniles midieron 28.16; (SD=1.93) de longitud a los 45 días, con un peso promedio de 4.75g; (SD=1.49). Los prejuveniles presentaron una pigmentación inicial en la mandíbula superior e inferior con tintes oscuros en forma de puntos y de manera dispersa sobre la cabeza. En los juveniles se observó el mismo patrón de pigmentación, disminuyendo hacia el margen del pedúnculo caudal. Las características descriptivas de la etapa de desarrollo embrionario de E. mexicanus son típicas del período de desarrollo de los peces de la familia Gerreidae, en particular en el caso de las especies E. brasilianus y E. lineatus que habitan en ambientes marinos. Sin embargo, sus caracteres morfométricos son diferentes con respecto al diámetro y el tamaño de los huevos y de la gota de aceite, ya que en E. mexicanus son más grandes que los de las especies marinas y son similares a los de los peces de agua dulce. Con respecto a la pigmentación, la larva con saco de E. mexicanus presenta un olor olivo y amarillo sobre el margen del notocordio, lo cual difiere a lo reportado para E. lineatus,ya que en esta muestra un grupo de melanóforos entre los miomeros nueve al 13 como principal característica, y para Diapturus peruvianus por presentar tres manchas en el margen dorsal de los intestinos desde la inserción de la aleta pectoral hasta el ano. Los resultados de este estudio son los primeros registrados para esta especie y han generado información sobre aspectos de su biología reproductiva y el desarrollo de la vida temprana.

Most studies on Eugerres mexicanus mainly consider biogeographic and systematic aspects and rarely address reproductive characteristics, which are useful for fishery population management plans. This study aimed at evaluating the ontogeny of E. mexicanus, based on 30 embryos and 30 larvae sampled by induced spawning of breeders, taken in February 2009 from the Usumacinta River in Tenosique, Tabasco, Mexico. All descriptions of the embryonic development were based on morphometric and meristic data and followed standard methods. Eggs, recovered at the gastrula stage, had an average diameter of 1.17mm (SD=0.08). The bud stage appeared during the first three hours of development, in which the posterior side was adhered to the vitellus; Kupffer´s vesicle was visible. Yolk-sac larvae hatched 18 hours after fertilization, exhibiting a light brown color and an average total length of 2.94mm (SD=0.70); the preflexion stage was reached eight days after hatching, with a total average length of 4.67mm (SD=0.50) and a total notochord length of 4.45mm (SD=0.50). The flexion stage was reached on the 16th day, with an average total length of 6.66mm (SD=1.53), while postflexion was reached on the 24th day, with 10.33mm (SD=1.45). The pre-juvenile stage was reached on the 33rd day, with a total length of 14.30mm (SD=0.93), showing IX spines and 10 rays and III spines and eight rays in the dorsal and anal fins, respectively. The juvenile stage was reached by the 45th day, with an average length of 28.16mm (SD=1.93) and average weight of 4.75g (SD=1.49). Prejuveniles showed an initial pigmentation with dark colored dots in the superior and inferior jaw and dispersed on the head, while juveniles presented the same pigmentation pattern, decreasing towards the margin of the caudal peduncle. In conclusion, the embryonic developmental stages of E. mexicanus were typical for the Gerreidae group. However, their morphometric characters were slightly different since the diameter and size of the drop of oil were bigger than those reported for marine species. In addition, regarding pigmentation, the yolk-sac larvae of E. mexicanus were olive and yellow on the margin of the notochord, which differs from those reported for other species. This is the first recorded report on the reproductive biology and early life development of this species.

The tuberculosis has increased by the emergence of multidrug-resistant strain (MDR). Was associated clinical course of patients with tuberculosis and treatment resistance. 268 samples were obtained, the resistance to drugs was determined for blue Alamar; 41.04% corresponded to strain sensitive to all the drugs; 17.91% MDR. The resistance was: isoniazid 28%, rifampin 52%, streptomycin 24%, and ethambutol 27%. Of 268 patients, 197 were virgins to treatment, of which 44% presented primary resistance, but of these, only 5% MDR. 71 patients (26.49%) with previous treatment presented secondary resistance, of which 14.55% was MDR. At the end of the follow-up, 72% recovered, 21% remained sick, and 7% died. The patients with better forecast were with sensitive strain, followed by patients with primary resistance and those of badly forecast they were MDR.

La tuberculosis ha incrementado por el surgimiento de cepas multidrogorresistentes (MDR). Se asoció la evolución clínica de pacientes con tuberculosis y resistencia al tratamiento. Se obtuvieron 268 muestras, la resistencia a fármacos se determinó por Alamar azul; 41.04% correspondieron a cepas sensibles a todos los fármacos; 17.91% MDR. La resistencia fue: isoniazida 28%, rifampicina 52%, estreptomicina 24% y etambutol 27%. De 268 pacientes, 197 eran vírgenes a tratamiento, de los cuales 44% presentaron resistencia primaria, pero de estos, solo 5% MDR. 71 pacientes (26.49%) con tratamiento previo presentaron resistencia secundaria, de los cuales 14.55% fueron MDR. Al final del seguimiento, 72% sanó, 21% permaneció enfermo y 7% falleció. Los pacientes con mejor pronóstico fueron con cepas sensibles, seguidos de pacientes con resistencia primaria y los de mal pronóstico fueron MDR.

Seguindo a proposta de uma disciplina de mecanica quantica com enfoque em física experimental [P.R.S. Gomes e T.J.P. Penna, Revista Brasileira de Ensino de Física 10, 34 (1988)], neste artigo apresentamos um metodo simples para o estudo da perda de energia de partículas alfa em ar, geralmente apresentado, quando disponível, em laboratório avancados no final dos cursos de graduacao em física e física medica, onde apresentamos um metodo novo e simples para a determinação do poder de frenamento de partículas alfa no ar e a obtençao da curva de Bragg.

Following the proposal of a quantum physics course with an experimental emphasis [P.R.S. Gomes and T.J.P. Penna, Revista Brasileira de Ensino de Física 10, 34 (1988)], in this work, we present a new simple method for the study of the stopping power of alfa particle in air, usually presented, when available, in advanced labs in physics and in medical physics courses. In this method, the Bragg's curve can be obtained both qualitative and quantitatively.

The design and characterization of an innovative device for plasma cleaning, based upon a non-conventional radio-frequency discharge, is described. The RF fields are produced by an antenna placed inside the metallic vacuum chamber. Theoretical models are described to calculate both the electro-magnetic field structure and the spatial impurity distribution, due to erosion of the antenna. The electron energy distribution function is determined with a standard RF-filtered electrostatic probe; it is found that the plasma is well described by a Druyvesteyn energy distribution function.

We here continue the review on the work of Octavio Novaro and collaborators in the important field of nonadditivity of intermolecular interactions and catalysis, with special interest in the work that Sidonio Castillo contributed to this effort before his demise. His early work with Polish coauthors on methane and ammonia trimers and with British coauthors on N3, P3, N4 and P4 are highlighted. Then our focus will shift mainly to his work on the activation of methane, silane and germane starting with his Ph.D. thesis under O. Novaro and ending in his last papers with the present authors which marked the end of his short but brilliant career.

Aquí continuaremos la revisión del trabajo de Octavio Novaro y sus colaboradores en los importantes campos de la no aditividad de las interacciones intermoleculares y de la catálisis, enfatizando las contribuciones de Sidonio Castillo que resultaron altamente útiles en este esfuerzo conjunto, antes de su prematuro fallecimiento. Sus primeros trabajos, con reconocidos científico polacos en los trímeros de metáno y amoniaco y con coautores ingleses en trimeros y tetrameros de fósforo y nitrógeno, serán presentados primero, seguidos de sus estudiós sobre la activación catalítica de moléculas de metáno, silano y germano (de alto potencial en aplicaciónes valiosas). Sus primeros trabajos en catálisis formaron parte de su tesis doctoral dirigida por O. Novaro y los últimos fueron consecuencia de las tesis doctorales que el Dr. Castillo dirigió a los otros dos coautores de esta revisión. Esta labor fue desgraciadamente interrumpida por la muerte de Sidonio. Así concluyó su corta pero brillante carrera.

Pulsed laser deposition (PLD) is extensively employed for the growth of thin films. The laser-material interaction involves complex processes of heating, melting, vaporization, ejection of atoms, ions and molecules, shock waves, plasma initiation, expansion and deposition onto a substrate. The understanding of the spatial and temporal distribution of a plasma parameters in a laser-produced plasma is important to the control of thin film growth process. In this work we have studied the dynamics of laser ablated graphitic carbon plasma expanding into vacuum using a spectroscopic imaging suitable as an in situ & automated diagnostic sampling technique for PLD. Time-resolved spectra, that were also spatially resolved in one dimension along the axis of plasma expansion, were obtained using a time-gated intensified charge-coupled device (ICCD) coupled to a stigmatic Czerny-Turner spectrograph. Plasma parameters such as electron density, temperature and plume velocity expansion were extracted directly from the analysis of the C II (2s²3d-2s²4f) transition.

The importance of fragmentation of water molecules by heavy ions is discussed for several different physical environments, including tumor treatment, planetary sciences and fission reactors. The characteristics of the fragmentation yields by electrons, protons and photons are presented and compared with fragmentation yields of water molecules by C3+ and O5+ ions at energies corresponding to the Bragg peak. It is shown that for low energy electron loss and high energy electron capture, the water molecules essentially blow-out, releasing a much larger fraction of Oq+ ions as compared with electrons, protons and photons.

The automated BACTEC MGIT 960 system was compared with the method of proportion (MP) for testing susceptibility of Mycobacterium tuberculosis to antituberculous drugs. 275 strains of M. tuberculosis isolated in Chile from 270 patients between 2001 and 2003 were tested. Concordance of BACTEC MGIT 960 with MP depending on the antituberculous drug tested was the following: 97.0% for streptomycin, 98,9% for rifampicin, 97,4% for isoniazid and 98,1% for ethambutol. Total resistance to antituberculous drugs of the 275 strains of M. tuberculosis tested varied from 20.4 % assessed by MP to 25.1% evaluated by BACTEC MGIT 960. These differences were not significant (p: ns; t test). BACTEC MGIT 960 yielded 17 strains as resistant. These same 17 strains were detected as sensitives by MP. Therefore, BACTED MGIT overestimates the number of resistant strains. In our study BACTEC MGIT 960 showed a very good concordance with MP and besides it allowed to get the results in a much shorter period of time than MP. Additional analysis are needed to know the factors envolved in BACTED MGIT overestimation of resistant strains

Se comparó el método automatizado BACTEC MGIT 960 con el método de las proporciones (MP) para la determinación de la susceptibilidad a drogas anti tuberculosas de 275 cepas de Mycobacterium tuberculosis aisladas de 270 pacientes en Chile entre 2001 y 2003. La concordancia del BACTEC MGIT 960 con el MP según las drogas estudiadas fue de: 97,0% para estreptomicina, 98,9% para rifampicina, 97,4% para isoniazida y 98,1% para etambutol. Los porcentajes globales de resistencia a drogas anti-TBC de las 275 cepas de M. tuberculosis estudiadas, determinados por el BACTEC MGIT960 y el MP fueron de 25,1% y 20,4% respectivamente. Esta diferencia no fue estadísticamente significativa. El BACTEC MGIT 960 dió como resistentes 17 cepas que fueron sensibles por el MP, sobrestimándose por este método la información de cepas resistentes. El BACTEC MGIT 960 en nuestra experiencia presentó una muy buena concordancia con el MP permitiendo un notable acortamiento en el tiempo de obtención de los resultados. Sin embargo, la mayor determinación de cepas resistentes por parte de este método requiere de nuevos análisis que permitan conocer los factores que inciden en este fenómeno