Resumen: Antecedentes y Objetivos: Hyptis suaveolens es una planta bien conocida en América Latina por sus propiedades medicinales. A pesar de sus diversos usos en la medicina tradicional, hay pocos reportes de su composición química. Además, se conoce su actividad contra bacterias que afectan al ser humano, pero existen pocos reportes acerca de su actividad sobre bacterias fitopatógenas, específicamente sobre aquellas que afectan cultivos. En este contexto los principales objetivos de este trabajo fueron determinar la actividad antibacteriana de hojas de H. suaveolens en bacterias fitopatógenas y su perfil fenólico, con el fin de contribuir al conocimiento de la composición fitoquímica y bioactividad de H. suaveolens para aplicaciones fitosanitarias. Métodos: El material vegetal fue colectado y las partes aéreas se secaron, molieron y extrajeron con metanol. El extracto crudo fue probado contra dos cepas bacterianas fitopatógenas (Chryseobacterium sp. y Pseudomonas sp.). Finalmente, se identificaron y cuantificaron compuestos fenólicos utilizando cromatografía de líquidos de ultra alta resolución acoplada a espectrometría de masas. Resultados clave: El extracto crudo de H. suaveolens mostró una actividad antibacteriana moderada en contra de Chryseobacterium sp., y se identificaron y cuantificaron 14 compuestos fenólicos, destacando al ácido rosmarínico, el cual mostró ser el más abundante, seguido de quercetina-3-glucósido y rutina. Seis compuestos fenólicos fueron identificados y cuantificados por primera vez en H. suaveolens. Conclusiones: En este estudio se demostró la actividad antibacteriana de las hojas de H. suaveolens y su correlación con la identificación y cuantificación de 14 compuestos fenólicos, particularmente con la presencia del ácido rosmarínico.

Abstract: Background and Aims: Hyptis suaveolens is a well-known plant in Latin America for its medicinal properties. Despite its diverse uses in traditional medicine, there are few reports concerning its chemical composition. In addition, the antimicrobial activity against human-pathogen bacteria is known, but there are few reports about its activity on phytopathogenic bacteria, specifically for those affecting important crops. In this context, the main aims of this work were to determinate the antibacterial activity of H. suaveolens leaves on phytopathogenic bacteria, and their phenolic profile, in order to contribute to the knowledge of the phytochemical composition and bioactivity of H. suaveolens for phytosanitary applications. Methods: The plant material was collected, and the aerial parts were dried, milled, and extracted with methanol. The crude extract was tested against two phytopathogenic bacterial strains (Chryseobacterium sp. and Pseudomonas sp.). Finally, phenolic compounds were identified and quantified using ultra-high performance liquid chromatography coupled with mass spectrometry. Key results: The crude extract of H. suaveolens exhibited a moderate antibacterial activity against Chryseobacterium sp., and 14 phenolic compounds were identified and quantified, highlighting rosmarinic acid, which showed the highest concentration followed by quercetin-3-glucoside and rutin. Six phenolic compounds were identified and quantified for the first time in H. suaveolens. Conclusions: In this work, the antibacterial activity of H. suaveolens leaves was demonstrated and it may correlate with the identification and quantification of 14 phenolic compounds, particularly with the presence of rosmarinic acid.

In the study was used 333 15-month-old beef heifers with body condition of 6 on average (scale 1-9). On this, 53.5% presented an active corpus luteum at the beginning of the study. On day 0, an intravaginal device with 0.5 g of progesterone (IVD) was placed and 2 mg of estradiol benzoate was injected. On day 8 the IVD was removed and 0.5 mg of cloprostenol and 0.5 mg of estradiol cypionate were i.m. injected. On day 10, artificial insemination at fixed time (IATF) was carried out, distributing the animals at random to be inseminated in three-time ranges: I) 48-50 h; II: >50-53 h; III) >53-56 h. Frozen semen in 0.5 ml straws was used. Pregnancy diagnosis was performed by ultrasound at 30 days post-IATF. Two animals lost the DISP and were excluded from the analysis. There was no effect on pregnancy rate of the time range in which the IATF was performed after the DISP was removed (I: 64.0%, II: 69.8%, III: 66.9%). It is concluded that in beef heifers using the ovulation synchronization protocol of the study, the IATF can be performed between 48 and 56 h after the removal of the device without affecting the pregnancy rate.

Se utilizaron 333 vaquillonas para producción de carne con 15 meses de edad y condición corporal promedio de 6 (escala 1-9). El 53.5% presentó un cuerpo lúteo activo al inicio del trabajo. En el día 0, se colocó un dispositivo intravaginal con 0.5 g de progesterona (DISP) y se inyectó 2 mg de benzoato de estradiol. El día 8 se retiró el DISP y se inyectó 0.5 mg de cloprostenol y 0.5 mg de cipionato de estradiol i.m. El día 10 se realizó la inseminación artificial a tiempo fijo (IATF), distribuyéndose los animales al azar para ser inseminados en tres rangos horarios: I) 48-50 h; II: >50-53 h; III) >53-56 h. Se utilizó semen congelado en pajuelas de 0.5 ml. El diagnóstico de gestación se realizó mediante ultrasonografía a los 30 días pos-IATF. Dos animales perdieron el DISP y fueron excluidos del análisis. No se observó efecto del rango horario en que se realizó la IATF luego de retirado el DISP sobre el porcentaje de preñez (I: 64.0%; II: 69.8%; III: 66.9%). Se concluye que en vaquillonas para carne utilizando el protocolo de sincronización de la ovulación del estudio se puede realizar la IATF entre las 48 y 56 h pos-retiro del dispositivo sin afectar el porcentaje de preñez.

Liquid effluents have been treated by electrocoagulation (EC), obtaining encouraging results in the removal of contaminants. The aim of this study was the application of the EC for the treatment of acid whey with reduced organic loading . Whey were analyzed for their pH, pZ, isoelectric point and COD. We used a batch-type electrochemical reactor of 2 L and a study volta and chronopotentiometric conditions for potential and current using 3 electrodes supported on Teflon plate separation of 10 mm, aluminum and iron as anode and graphite oxide ruthenium/titanium cathode and a reference electrode. In and for the EC was evaluated considering the kinetics in response the highest percentage of COD removal or efficiency percentage, and variation of pH and pZ. We conclude that the best arrangement of electrodes was the Al-OxRut. In the first 8 hours, the pH increased from 4,82 to 8,67 and 6,56 for Fe and Al species. Among the top 10 and 12 h of EC maximum is reached significant change and the increased removal of COD by the formation of colloids and emulsions oxyhydroxides of iron and/or aluminum in the occlusion re-entering the organic macromolecules. The COD removals were higher with the pairs Al-OxRut and Al-Graf, who had a 83 % and 66 % respectively at 10 h. To arrange for iron is not reached up to 50 % efficiency.

Efluentes líquidos han sido tratados mediante electrocoagulación (EC), obteniendo resultados alentadores en remoción de contaminantes. El objetivo ha sido estudiar la aplicación de la EC para el tratamiento del lactosuero ácido, con reducción de carga orgánica. Se analizó en lactosuero valores de pH, pZ, punto isoeléctrico y DQO. Se usó un reactor electroquímico tipo batch de 2 L y se realizó un estudio volta y cronopotenciométrico para obtener condiciones de potencial y corriente empleando 3 electrodos soportados sobre placa de teflón y separación 10 mm; aluminio y hierro como ánodos, grafito y óxido de rutenio/titanio como cátodos y un electrodo de referencia. En y durante la EC se evaluó la cinética considerando como respuesta el mayor porcentaje de remoción de la DQO o porcentaje de eficiencia y variación del pH y pZ. Se concluye que el mejor arreglo de electrodos fue el del par Al-OxRut. Se obtuvo una variación del pH y pZ como resultado de reacciones anódicas y catódicas; las principales variaciones se producen con los arreglos Fe-OxRut y Al-OxRut. En las primeras 8 horas el pH incrementó de 4,82 a 8,67 y a 6,56 para las especies de Fe y Al. Entre las primeras 10 y 12 h de la EC se alcanza la máxima variación significativa así como la mayor remoción de la DQO por formación de coloides y emulsiones de oxihidróxidos de hierro y/o aluminio en los que se reincorporan por oclusión, las macromoléculas orgánicas. Las mayores remociones de DQO fueron con los pares Al-OxRut y Al-Graf, que presentaron un 83 % y 66 %, respectivamente a las 10 h. Para los arreglos de hierro no se llegó a alcanzar el 50 % de eficiencia.

Three experiments were conducted (EI, n: 209; EII, n: 208; y EIII, n: 188) using Angus heifers in order to compare the use of estradiol cypionate (EC) at device removal or estradiol benzoate (EB) 24 h after in a FTAI protocol. On day 0 heifers received a progesterone intravaginal device plus EB. On day 8, the intravaginal device was removed and heifers received a luteolytic dose of PGF. At device removal heifers were randomized to receive either EC at 0 h or EB at 24 h. On day 10, 50-53 h after device removal, fixed timed artificial insemination was performed using frozen/ thawed semen of proven fertility (3 bulls for EI and 2 for EII and EIII) and two inseminators. Pregnancy rates were not different between treatments (EI: 67.8%; EII: 59.2%; EIII: 58.4%) or inseminators (p>0.05); however a bull effect was observed in experiments I (B: 47.8%; F: 75.0%; M: 72.0%; p<0.05) and II (M: 68.8%; ME: 48.5%; p0.05). Interactions were not significant. In conclusion, according to our finding, estradiol cypionate could be used instead of estradiol benzoate to synchronize ovulation without affecting the pregnancy rate at fixed timed artificial insemination.

Se realizaron 3 ensayos (EI, n: 209; EII, n: 208; y EIII, n: 188) utilizando vaquillonas Angus con el objetivo de evaluar el uso del cipionato de estradiol administrado al retirar un dispositivo intravaginal con progesterona sobre el porcentaje de preñez a la IATF. En el día 0 se colocó un dispositivo intravaginal más benzoato de estradiol. En el día 8 se retiró el dispositivo y se inyectó un agente luteolítico y las vaquillonas fueron distribuidas al azar para recibir cipionato de estradiol en ese momento o benzoato de estradiol 24 horas después. En el día 10, 50-53 h post retiro del dispositivo, se realizó IATF utilizando semen de toros de probada fertilidad (3 en EI, 2 en los EII y EIII) y dos inseminadores. No se observaron efectos del tratamiento (EI: 67,8%; EII: 59,2%; EIII: 58,4%) y del inseminador (p>0,05); no obstante se observó un efecto del toro en EI (B: 47,8%; F: 75,0%; M: 72,0%; p<0,05) y EII (M: 68,8%; ME: 48,5%; p0,05). Se concluye que, el cipionato de estradiol aplicado al retirar un dispositivo con progesterona puede reemplazar al benzoato de estradiol sin afectar el porcentaje de preñez.

With the purpose of characterizing the growth of the root system of table grapes (Vitis vinifera L.) cv. Thompson Seedless and its relationship with soil temperature, research was carried out during the 2004-2005 growing season in vineyards in the Copiapó and Huasco Valleys. Four plants were chosen and rhizotrons were used to measure the growth of the root system. Measurements were performed once a week from September 2004 to September 2005, estimating the intensity of root growth and its annual distribution in the ranges of 0 to 40, 40 to 80 and 80 to 120 cm of soil depth. Temperature sensors were installed in four plants at 25, 50, 75 and 100 cm of soil depth, and the temperature was registered every 1 h. The thermal diffusivity of the soil was calculated based on the annual mean temperature and annual thermal amplitude values. Root growth occurred throughout the year, presenting lower intensity in July (winter). Root systems presented different patterns in the distribution of growth intensity in the three soil depths, with variations in the order of five times in maximum annual growth intensity among sites. High thermal diffusivity in soils favored root growth.

Con el objetivo de caracterizar el crecimiento del sistema radical de la vid (Vitis vinifera L.) cv. Thompson Seedless y su relación con la temperatura del suelo, durante la temporada 2004-2005 se llevó a cabo un estudio en parronales ubicados en los valles de Copiapó y Huasco. Se instalaron cuatro cámaras de observación de raíces o rizotrones en plantas homogéneas, en plena producción, pie franco, sanas, y ubicadas en diferentes localidades de la región. Las mediciones del crecimiento de las raíces se efectuaron semanalmente, desde septiembre de 2004 hasta completar 1 año, estimándose la intensidad de crecimiento radical anual y su distribución en los rangos de 0 a 40, 40 a 80 y 80 a 120 cm de profundidad. Adicionalmente, se instalaron sensores de temperatura a 25, 50, 75 y 100 cm de profundidad y se registró la temperatura cada 1 h. Con los valores de temperatura media anual y amplitud térmica anual se calculó la difusividad térmica de los suelos. Se observó crecimiento radical durante todo el año presentando menor intensidad en el mes de julio (invierno). Las raíces mostraron diferentes patrones en la distribución de la intensidad de crecimiento en los tres rangos de profundidad, con variaciones entre los sitios de hasta cinco veces en la máxima intensidad de crecimiento anual. Suelos con difusividades térmicas altas presentaron ambientes favorables para el crecimiento de raíces.

Pure nitrogen, 30% argon/70% nitrogen, 50% argon/50% nitrogen, 70% argon/30% nitrogen plasma immersion ion implantation (PIII) processes onto aluminium samples has been performed at 2 to 6 kV negative bias and 50 to 150 us pulse widths, the sample temperature being established at 400 °C. Incident fluencies of ~10(18) atoms/cm² were used to investigate the diffusion behaviour and AlN phase formation in the samples. X-ray diffraction (XRD) shows the formation of the cubic phase of AlN with both pure nitrogen and all the mixtures whereas the hexagonal phase becomes apparent only in the 50% mixture and in pure nitrogen. The characteristic peak of AlN has also been determined by Raman spectroscopy. The microhardness was found to be always maximal with the 50% nitrogen 50% argon mixture.

RESUMEN Este artículo presenta una propuesta de formación de directivos de centros educativos orientada desde la investigación de los problemas propios de la gestión escolar. El proyecto se inicia con la realización de un Foro Virtual, que propicia la integración para la construcción colectiva desde el reconocimiento de la diferencia y la singularidad de los contextos sociales y educativos. Participan delegados de ocho países del CAB quienes, a través de la reflexión crítica, identifican aspectos problemáticos de la gestión escolar, proponen los ámbitos de actuación del directivo docente y, elaboran los principios que deben orientar los programas en las universidades para que respondan a los retos que plantea la integración, incluyendo una visión integral y de totalidad de lo humano.

ABSTRACT This paper presents a proposal for training directors for educational institutions, research-oriented from the point of view of the problems of school management. The project begins with the realization of a virtual forum that enables the integration for the collective, from the recognition of the difference and uniqueness of social and educational contexts. Speakers from eight countries from the CAB identify problematic aspects of school management, through critical reflection, propose areas of performance of the management and develop the principles that should guide the programs at universities to respond to the challenges of integration, including a comprehensive and wholeness vision of what is human.

Samples of pure Titanium were treated by means a PIII process using a dense DC glow discharge with different mixtures of nitrogen-oxygen and oxygen pure. The surface of treated samples was analyzed by means of different techniques such as X-ray diffractometry, Scanning Electron Microscope, Vickers Microhardness tester and profilometer. We conclude that the modified surface is formed by TiN0.26 diffused into TiO2 in rutile phase, forming a uniform layer up to 10 μm in thickness and whose resultant microhardness is almost five times greater than that of untreated titanium. Some control over the superficial parameters is taken by varying the proportion of nitrogen-oxygen at a pressure of 1x10-2 Torr (~1.33 Pa), obtaining a thicker layer, a harder surface or a reduced roughness. The identified phases have biocompatible properties, which provide interest in the bioengineering field.

Some recent results concerning the synthesis of carbon nanostructures in a thermal plasma generating by a plasma torch are presented. Several tests were carried out in different operational conditions. The plasma was formed with argon and different gas mixtures of argon-acetylene or argon-methane to which some catalyst materials (ferrocene and cerium oxide) were added. These catalysts were introduced into the plasma in a solid (powder) or/and a gaseous state. Their feeding rate into the plasma jet was fixed along with some other operating conditions such as plasma power, gas flow rate and reactor pressure. The principal main feature observed was a short reaction time so that each test lasted for no longer than 5 minutes. The solid products obtained were collected and prepared for following analyses. The products were examined using XRD and TEM techniques in order to characterize the morphological structure of their samples. The spatial distribution of temperature in the plasma was evaluated by in-situ emission spectroscopy. The self-absorption was taken into account by simulating an integrated radiation in relation to the Swan band d³pig -> a³piu(0,0), emitted by the C2 radical. Also, the exhaust gases were characterized by gas chromatography during each test.

This work presents the use of a hybrid-neural model for predictive control of a plug flow polymerisation reactor. The hybrid-neural model (HNM) is based on fundamental conservation laws associated with a neural network (NN) used to model the uncertain parameters. By simulations, the performance of this approach was studied for a peroxide-initiated styrene tubular reactor. The HNM was synthesised for a CSTR reactor with a radial basis function neural net (RBFN) used to estimate the reaction rates recursively. The adaptive HNM was incorporated in two model predictive control strategies, a direct synthesis scheme and an optimum steady state scheme. Tests for servo and regulator control showed excellent behaviour following different setpoint variations, and rejecting perturbations. The good generalisation and training capacities of hybrid models, associated with the simplicity and robustness characteristics of the MPC formulations, make an attractive combination for the control of a polymerisation reactor.

A treatment based on progesterone impregnated vaginal sponges has been used to control breeding in suckled beef cows under grazing conditions. However, fertility has not always been satisfactory. The objective of this trial was to determine whether fertility of treated cows was affected by the following factors: parity and duration of treatment (exp. 1), presence of signs of oestrus at the moment of timed AI and duration of postpartum in anoestrus cows (exp. 2), the time for double timed AI and reduction to a single timed AI (exp. 3). Spring-calved suckled Angus cows 30 to 90 days (d) postpartum, in good body condition, were used. Cows received 10 mg of oestradiol benzoate i.m. and a vaginal sponge containing 2 g of progesterone (ESP treatment). Exp. 1. Parity (primiparous, n=53 vs multiparous, n=83) and duration of ESP (8 d, n=72 vs 11 d, n=71) were evaluated. Timed artificial inseminations were carried out 48 and 72 hs after sponge removal (AI-T). Pregnancy rates at AI-T and accumulated after 30 days of AI (pregnancy rate at day 30 = pregnancy at AI-T and at return to oestrus) were determined. Both factors did not interact (p 0.05). ESP duration had no effect on pregnancy rate at AI-T and at day 30: 38 vs 42% and 56 vs 61%, 8 vs 11 d respectively (p 0.05). Multiparous cows tended to present higher pregnancy rates at AI-t and at day 30: 39 vs 23% and 46 vs 28% (p < 0.1) multiparous vs primiparous respectively. Exp. 2. Anoestrus multiparous cows (n=124) were treated with ESP during 11 d. Procedures were similar to those in exp. 1. Oestrous rate was 24% and it appeared between 36 and 48 hours after treatment. Pregnancy rate at AI-t was 53 and 44% in oestrous cows and non oestrous cows (p 0.05) while pregnancy rate at day 30 was 64 and 60% respectively. In those cows in which exact parturition date was available no different pregnancy rate at AI-t was found when cows were treated between postpartum days 30 to 59 (n=15), 60 to 89 (n=28) or 90 to 145 (n=20): 57, 55.3 and 52.6% respectively (p 0.05). Exp. 3. Multiparous cows were treated with ESP during 11 d. The time for double AI-T had no effect on pregnancy rate: 38% when inseminated either at 48 and 72 hs (n=42) or 40 and 64 hs (n=47). The amount of AI-T did not affect the pregnancy rate: 22% with AI-T at 48 and 72 hs (n=46) vs 29% with one AI-T at 56 hs (n=48) (p 0.05). In no case was pregnancy rate at day 30 affected. It is concluded that in ESP-treated postpartum beef cows, fertility tends to be lower in primiparous than multiparous cows. However, fertility is not affected by reduction of treatment duration from 11 to 8 d, presence of signs of oestrus in induced cows at timed AI, duration of postpartum anoestrus, displacement of double timed AI in 8 hours or reduction from double to single timed AI

Vacas Angus con cría, entre 30 y 90 días (d) posparto y con buena condición corporal, recibieron 10 mg de benzoato de estradiol i.m. y 2 g de progesterona mediante esponja vaginal (tratamiento ESP). Se determinó si la fertilidad fue afectada por: la duración del tratamiento y el número de partos (Exp. 1); la presentación de celo inducido al momento de la inseminación artificial sistemática –IAS– y la longitud del posparto, en vacas en anestro (Exp. 2); y la hora o la cantidad de IAS (Exp. 3). Exp.1. Se trató con ESP durante 8 u 11 d a vacas primíparas y multíparas. Se hizo IAS a las 48 y 72 horas de retiradas las esponjas. La IA continuó por 30 d. Se determinaron las tasas de preñez de la IAS y la acumulada en 30 d (preñadas en la IAS + preñadas en el retorno). El ESP aplicado durante 8 d (n=72) y 11 d (n=71) no afectó la preñez de la IAS: 38% y 42% respectivamente, ni la preñez acumulada en 30 d: 56% y 61%, respectivamente (p 0.05). Las multíparas (n=83) tendieron a una mayor tasa de preñez respecto de las primíparas (n=53) en la IAS: 39% y 23%, y también en la acumulada en 30 d: 46% y 28%, respectivamente (p < 0.1). Exp. 2. Se trataron 124 vacas multíparas en anestro con ESP durante 11 d. Se inseminó como en Exp. 1. La tasa de celo inducido fue del 24% y se manifestó entre las 36 y 48 horas postratamiento. La preñez de la IAS fue del 53% en las vacas que presentaron celo y del 44% en las vacas sin celo, mientras que la preñez acumulada fue del 64% y 60%, respectivamente (p 0.05). Las vacas en anestro tratadas entre los d posparto 30 a 59 (n=15), 60 a 89 (n=28) y 90 a 145 (n=20) tuvieron similar tasa de preñez en la IAS: 53%, 57% y 55%, respectivamente (p 0.05). Exp.3. Se trataron vacas multíparas con ESP durante 11 d. En un rodeo se determinó el efecto de la IAS a las 40 y 64 horas (n=47) respecto de la IAS a las 48 y 72 horas (n=42): la tasa de preñez fue del 38% en ambos grupos. En otro rodeo se determinó el efecto de una IAS simple; las vacas se distribuyeron entre la IAS a las 48 y 72 horas (n=46) o las 56 horas (n=48): la tasa de preñez fue del 22 y 29%, respectivamente (p 0.05), la preñez acumulada al d 30 no fue diferente. Se concluye que la fertilidad de vacas de cría tratadas con ESP tiende a ser menor en primíparas que en multíparas; pero no es afectada por la reducción del tratamiento de 11 a 8 d, la presentación o no de celo inducido al momento de la inseminación sistemática en vacas en anestro, la longitud del anestro posparto, el desplazamiento de la doble inseminación sistemática en 8 horas o la reducción a una inseminación sistemática simple