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An analysis of the scientific production of Ecuador is performed by means of the composite indicator computed for Ecuador-based authors as compared to their counterparts of other South American countries. The dataset employed was obtained from the Databricks platform of the ELSEVIER's International Center for Science Research, ICSR. Therefore, this analysis is limited to the metadata of the documents published in journals indexed in SCOPUS. Comparison of the results obtained for two decades: 2001-2010 and 2011-2020 showed that the number of Ecuador-based researchers has significantly increased in different areas of knowledge. Moreover, comparison between the total number of authors that worked in Ecuador at any given year of the 2011-2020 period and the number of authors that are still working in this country up to the date of the data extraction (i.e., June 2021) showed an average of ∼68% of permanency. Analysis of the percentage distribution in terms of range quarters of the composite indicator (i.e., Q4: 0-1.5, Q3: 1.5-3.0, Q2: 3.0-4.5, and Q1: 4.5-6.0) showed that nearly the totality of the Ecuador-based researchers has composite indicators that lay in the Q4 and Q3 ranges for all the scientific fields considered. The latter was observed to be an effect of the scientific impact of South American countries, with larger investments in science and technology in comparison to Ecuador (i.e., Argentina, Brazil, and Chile). Exclusion of this group of countries in the calculation of the composite indicator of Ecuador-based authors resulted in a noticeable increment of scientists with composite indicators within Q2. Finally, our results suggest, in agreement with previous studies, a correlation between the sustained growth of scientific productivity in the decade 2011-2020 with the scientific programs and policies created by the state, where the initiative of scientific culture is shown as a strategy for growth and development.

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Theoretical calculations focusing on the cleavage of the C-X bond in methyl halides (CH3X; X = Cl, Br, I) as mediated by CoI-based systems have been carried out using the hybrid functional ωB97-XD together with the basis set 6-311++G(2d,2p). A total of seven CoI-based compounds were evaluated: cob[I]alamin (CoICbl) in its base-on form and cobaloxime (CoICbx) with either no ligand or different ligands (either pyridine (PYR), tributylphosphine (TBP), dimethyl sulfide (DMS), cyclohexylisocyanide (CI), or 5,6-dimethylbenzimidazole (DMB)) at the lower axial position. For the large CoICbl system, an ONIOM scheme was employed, where the high layer was described at the DFT level and the low layer was computed using the semi-empirical method PM6. A full DFT model was employed for the CoICbx cases. An SN2-like mechanism was evaluated in all cases. The intrinsic reaction coordinate profiles suggested early transition states with activation energies of ≈ 12 kcal/mol, ≈ 10 kcal/mol, and ≈ 5 kcal/mol for C-Cl, C-Br, and C-I cleavage, respectively, which is consistent with the leaving group abilities of these halides. The evolutions of the atomic charges in and the bond orders of Co-C and C-X were computed, and the results confirmed the existence of early transition states (δBav≈ 40%), where the polarization Cδ+-Xδ- (%Ev ≈ 43%) is the determining factor in the reaction process. Finally, a comparison of all the determined parameters showed that the reaction in the DMB-CoICbx system resembles the process that occurs in the larger CoICbl, suggesting that the former system could be a reliable model for the study of reductive dehalogenation mediated by vitamin B12, which is key to the anaerobic microbiological treatment of halocarbon contaminants.

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In the present work, C-F bond cleavage mediated by the super-reduced form of cobalamin (i.e., CoICbl) was theoretically studied at the ONIOM(BP86/6-311++G(d,p):PM6) + SMD level of theory. Dispersion effects were introduced by employing Grimme's empirical dispersion at the ONIOM(BP86-D/6-311++G(d,p):PM6) + SMD level. In the first stage of the study, cobalamin was characterized in terms of the coordination number of the central cobalt atom. The ONIOM(BP86/6-311++G(d,p):PM6) results showed that the base-off form of the system is slightly more stable than its base-on counterpart (ΔE = E base-off - E base-on ~ -2 kcal/mol). The inclusion of dispersive forces in the description of the system stabilizes the base-on form, which becomes as stable as its base-off counterpart. Moreover, in the latter case, the energy barrier separating both structures was found to be negligible, with a computed value of 1.02 kcal/mol. In the second stage of the work, the reaction CoICbl + CH3F → MeCbl + F- was studied considering the base-off and the base-on forms of CoICbl. The reaction that occurs in the presence of the base-on form of CoICbl was found to be kinetically more favorable (ΔE ≠ = 13.7 kcal/mol) than that occurring in the presence of the base-off form (ΔE ≠ = 41.2 kcal/mol). Further reaction-force analyses of the processes showed that the energy barrier to C-F bond cleavage arises largely due to structural rearrangements when the reaction occurs on the base-on form of the CoICbl complex, but is mainly due to electronic rearrangements when the reaction takes place on the base-off form of the complex. The latter behavior emerges from differences in the synchronicity of the bond strengthening/weakening processes along the reaction path; the base-on mode of CoICbl is able to decrease the synchronicity of the chemical events. This work gives new molecular-level insights into the role of Cbl-based systems in the cleavage of C-F bonds. These insights have potential implications for research into processes for degrading fluorine-containing pollutants.

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La alta incidencia de un conducto peritoneo vaginal permeable contralateral ha llevado al desarrollo de nuevas técnicas laparoscópicas, las cuales han revivido una controversia alrededor de la exploración contralateral. Con el presente estudio observacional, analítico, prospectivo de cohorte, realizado en niños entre los 0 y los 15 años en el Servicio de Cirugía Pediátrica del Hospital Militar Central en el periodo comprendido entre mayo de 2005 y agosto de 2008, se evaluó la utilidad de la laparoscopia en el diagnóstico de la hernia inguinal contralateral. El estudio permitió determinar por medio de la laparoscopia, que pacientes cursaban con hernia inguinal contralateral para así realizar su corrección quirúrgica durante el mismo procedimiento, evitando así la posibilidad de una hernia complicada contralateral metacrónica, un nuevo riesgo anestésico y con el costo adicional de una segunda hospitalización; igualmente estos resultados se pudieron contrastar con las estadísticas mundiales...

The high incidence of a contralateral patent processus vaginalis has led to the development of new laparoscopic techniques which have revived the controversy around the contralateral exploration. With this project we evaluate the usefulness of laparoscopy in the diagnosis of contralateral inguinal hernia. It was performed in children between 0 and 15 years in the pediatric surgery service of the Central Military Hospital in the period between May 2005 and August 2008, through an observational, analytical, prospective cohort study. The study allowed us to determine through laparoscopy, which patients had contralateral inguinal hernia, making the correction in the same surgical time, avoiding the possibility of a complicated metachronous contralateral hernia, a new anesthetic risk and the cost of a second hospitalization; similarly these results were confonted with global statistics...

A alta incidência de ducto vaginal peritoneal permeável contralateral levou ao desenvolvimento de novas técnicas de laparoscopia, que reviveram a controvérsia em torno da exploração contralateral. Com este projeto foi avaliada a utilidade da laparoscopia no diagnóstico de hérnia inguinal contralateral. Foi realizado em crianças entre 0 e 15 anos no departamento de cirurgia pediátrica, Hospital Militar, no período entre maio de 2005 e agosto de 2008, através de um estudo, observacional analítico, prospectivo de coorte. O estudo constatou através de laparoscopia, que os pacientes que foram registrados com hérnia inguinal contralateral, realizando a correcção no mesmo tempo cirúrgico, evitaba a possibilidade de uma hérnia contralateral metachronous complicado, um novo risco anestésico e os custos de uma segunda internação e comparados com as estatísticas mundiais...

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Las lesiones traqueobronquiales por trauma cerrado de tórax son una entidad rara a cualquier edad y más aún en la población pediátrica. La mayoría de pacientes con este tipo de lesiones mueren antes de llegar al hospital, a causa de lesiones severas asociadas. Presentamos el caso de una niña de 2 años quien sufrió una lesión del bronquio fuente izquierdo, como consecuencia de un trauma cerrado de tórax en accidente autopedestre. A su ingreso se documenta neumomediastino y enfisema subcutáneo, por lo que se sospecha lesión de vía aérea la cual se confirma con tomografía y fibrobroncoscopia. Se maneja inicialmente en forma conservadora, con posterior reconstrucción de la vía aérea con una evolución excelente.

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OBJECTIVE: This study was performed to observe the number of pacemakers that had never been reprogrammed after implantation, and the effect of optimised output programming on estimated longevity of pulse generators in patients with pacemaker METHODS: Sixty patients with Teletronics Reflex pacemakers were evaluated in a pacemaker clinic, from the time of the beginning of its activities, in June 1998, until March 1999. Telemetry was performed during the first clinic visit, and we observed how many pulse generators retained nominal output settings of the manufactures indicating the absence of reprogramming until that date. After evaluation of the capture threshold, reprogramming of pacemakers was performed with a safety margin of 2 to 2.5:1, and we compared the estimated longevity based on battery current at the manufacturer's settings with that based on settings achieved after reprogramming. RESULTS: In 95% of the cases, the original programmed setting was never reprogrammed before the patients attended the pacemaker clinic. Reprogramming the pacemaker prolonged estimated pulse generator life by 19.7+/-15.6 months (35.5%). CONCLUSION: The majority of the pacemakers evaluated had never been reprogrammed. Estimated pulse generator longevity can be prolonged significantly, using this simple, safe, efficacious, and cost-effective procedure.

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Se presenta la experiencia del Hospital Universitario de San Ignacio (HUSI) en reparos herniarios por via preperitoneal, con una morbilidad y recurrencia dentro de los rangos publicados en la literatura. Se analizan los resultados de la cirugia en casos de hernias incarceradas, crurales y reproducidas que hasta el momento constituyen las principales indicaciones del procedimiento, el cual se proyecta hacia el futuro como una tecnica util y segura que permite su empleo en casi todos los tipos de defectos herniarios.

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En muchas aplicaciones agrícolas o biológicas, se ajustan modelos basados en funciones de producción Yi = (Xi, FONT FACE="Symbol">q /font>) + e para un conjunto de variables predictoras Xj j = 1,. . . , k y un vector parámetros FONT FACE="Symbol">q /font>. En este trabajo se presenta una alternativa para detectar observaciones influyentes, cuando la función de producción es univariada y la estimación de los parámetros se realiza por el método de Gauss - Newton.

Models of production functions Yi = (Xi , FONT FACE="Symbol">q /font>) + e, with explanatory variables xj , j=1,..., k and a parameter vector FONT FACE="Symbol">q /font> are used in agricultural and biological areas. In the present work we present an alternative to detect influent observations, when the production function is univariate and the Gauss-Newton method is used to estimate the parameters.

Em muitas aplicações agrícolas ou bilógicas, ajustam-se modelos baseados em funções de produção Yi = (Xi, FONT FACE="Symbol">q /font>) + e, para um conjunto de variáveis preditoras xj , j=1,..., k e um vetor de parâmetros FONT FACE="Symbol">q /font>. Neste estudo apresenta-se uma alternativa para detectar observações influentes, quando a função de produção é univariada e a estimação dos parâmetros é executada através do método de Gauss-Newton.

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En muchas aplicaciones agrícolas o biológicas, se ajustan modelos basados en funciones de producción Yi = (Xi, FONT FACE="Symbol">q /font>) + e para un conjunto de variables predictoras Xj j = 1,. . . , k y un vector parámetros FONT FACE="Symbol">q /font>. En este trabajo se presenta una alternativa para detectar observaciones influyentes, cuando la función de producción es univariada y la estimación de los parámetros se realiza por el método de Gauss - Newton.

Models of production functions Yi = (Xi , FONT FACE="Symbol">q /font>) + e, with explanatory variables xj , j=1,..., k and a parameter vector FONT FACE="Symbol">q /font> are used in agricultural and biological areas. In the present work we present an alternative to detect influent observations, when the production function is univariate and the Gauss-Newton method is used to estimate the parameters.

Em muitas aplicações agrícolas ou bilógicas, ajustam-se modelos baseados em funções de produção Yi = (Xi, FONT FACE="Symbol">q /font>) + e, para um conjunto de variáveis preditoras xj , j=1,..., k e um vetor de parâmetros FONT FACE="Symbol">q /font>. Neste estudo apresenta-se uma alternativa para detectar observações influentes, quando a função de produção é univariada e a estimação dos parâmetros é executada através do método de Gauss-Newton.

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This study was designed to compare the antihypertensive efficacy of nitrendipine and atenolol in young and middle-aged patients with mild or moderate essential hypertension and to assess treatment effects on plasma lipids and potential changes in left ventricular mass (LVM). After 2 weeks off medication and a 4-week placebo phase, patients who met the inclusion criteria [sitting diastolic blood pressure (DBP) 95 to 114 mm Hg, age below 50 years] entered a 12-week dose-adjustment and maintenance period with nitrendipine or atenolol. Serum lipids were determined before and after therapy. At the same time, LVM was evaluated echocardiographically (M mode). Twenty-two patients completed the double-blind, randomized study. After 12 weeks on nitrendipine, the systolic blood pressure (SBP) and DBP were reduced (p less than 0.005 and p less than 0.001, respectively). No significant changes in heart rate were observed. There were no changes in the lipid profile, and LVM was reduced from 93.7 to 23.4 to 82.4 +/- 22.6 g/m2 of body surface (p less than 0.05). On atenolol the SBP and DBP were reduced (p less than 0.001 and p less than 0.001, respectively). The expected reduction in heart rate was significant (p less than 0.05). Total cholesterol and LDL cholesterol increased by 11% (p less than 0.05) and 12.3% (p less than 0.01), respectively. HDL cholesterol showed a small reduction. Tryglycerides increased by 22% (n.s.). LVM did not change. In conclusion, nitrendipine and atenolol showed comparable antihypertensive efficacy.(ABSTRACT TRUNCATED AT 250 WORDS)

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Sixteen patients with mild or moderate essential hypertension received 1 to 8 mg/day of doxazosin (mean daily dose, 2.7 mg). Blood pressure reduction (supine and standing) was highly significant (p less than 0.001), and no significant changes in heart rate were observed. A significant reduction (p less than 0.01) in left ventricular mass was seen without a change in left ventricular systolic function. All side effects were mild, and only one patient withdrew from the study.

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Trece pacientes con Hipertensión Arterial Esencial leve a moderada concluyeron un estudio abierto con Doxazosin en dosis de 1 a 8 mg. La reducción de la presión arterial en las diferentes posiciones fue altamente significativa (p < 0,001), mientras que la frecuencia del pulso y el peso corporal no se modificaron . Los effectos secundarios fueron leves y solamente un paciente fue retirado del estudio. No se presentaron cambios significativos en los exámenes de laboratorio. En el estudio ecocardiográfico Modo M realizado en ocho pacientes se observó una reducción significativa de la Masa Ventricular (p < 0,01), sin modificaciones en la función sistólica del ventrículo izquierdo. Concluimos que el Doxazosin, un nuevo bloqueante alfa 1 postsináptico, es efectivo en el tratamiento de los pacientes con hipertensión arterial esencial leve a moderada como monoterapia, con pocos efectos secundarios, que no modifica el metabolismo lipídico y que exhibe un efecto beneficioso sobre el corazón, al reducir la Masa Ventricular sin cambios en la función sistólica del ventrículo izquierdo

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Veinte pacientes con hipertensión arterial esencial leve a moderada concluyeron un estudio cruzado distribuidos al azar en dos grupos: Grupo A: 10 pacientes que recibieron primero propranolol y posteriormente prazosin. Grupo B: 10 pacientes que recibieron inicialmente hidroclorotiazida y después prazosin. La reducción de la presión arterial en posición supina y de pie fue estadísticamente significativa y comparable con las tres drogas. Los efectos colaterales fueron menores con el prazosin. El análisis ecocardiográfico modo "M" en los pacientes con hipertrofia ventricular izquierda mostró reducción de la masa ventricular en 5 que recibieron propranolol y en 4 tratados con hidroclorotiazida. No encontramos reducción ulterior con el prazosin. La fracción de eyección y el acortamiento circunferencial de la fibra mejoraron en forma significativa con el prazosin (16 pacientes), no así con el propranolol ni con la hidroclorotiazida. Se concluye que el prazosin es una droga que puede ser utilizada como terapia inicial con pocos efectos secundarios a dosis bajas. Se propone el tratamiento secuencial de la hipertensión arterial leve a moderada en vez del esquema tradicional

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