Evaluación Dasométrica De Una Plantación De Pinus Radiata D. Don En El Sector San Andrés, Guano, Ecuador

There are scarce information concerning the growth and productivity of the trees of the plantation of Pinus radiata D. Don. This is usually found in the forest estate of the Haro-Maderas factory in a condition of soil with sandy loam texture, deep and moderately fast drainage, pH 6.7, fertility between low and high with the specific application of a pruning activity at the age of 5 years, and gradual monitoring every year until 8 years of age. This is considered as part of its management which constitutes a benchmark in the Tahuala sector. For this reason, this study aims to evaluate its forest mass. Circular plots of 8.92m radius were installed at an intensity of 4.33% ha-1 . This, however, is done through a systematic aligned sampling for the collection of dasometric information. The application of statistical estimators showed an altitude of 3145 masl. It reached an average total height of 12.76 m, a DAP of 15.27 cm, the total average tree-1 estimated volume of 0.16 m3 , and its projected value of 303.56 m3 ha-1 . The relationship between the DAPage variables and the average-age total height was high and significant. It has a correlation coefficient equal to 0.99, whose estimation was better with the linear type equation. It was suggested that thinning should be carried out with an intensity of 28.77%. In regards to the remaining trees, it will be very necessary to apply the silvicultural treatment of pruning

Estimación De Los Residuos Forestales En Los Aserraderos De Tres Cantones, Zona 3 Interandina, Ecuador

This paper focuses on the current situation of the availability and use of forestry waste generated in sawmills of the Ecuadorian interandina zone 3. It specifically highlights information about different types of waste, its volume, sales price, and final location. Through the stratification of the sample, 38, 25 and 19 surveys were carried out with loggers from the cantons of Riobamba, Ambato, and Latacunga with a level of reliability of 95%. It was stated that the most common waste are sawdust, shavings, and wood scrap. The monthly production average is 2.92, 1.64, and 2.74 tons of waste in the first village. 31.6%, 40%, and 31.6% of sawmills in Riobamba, Ambato and Latacunga sells from 6.1-8, 4.1-6, and 8.1-10 dollars per ton respectively. There was highly significant differences in the sale prices (p<0, 0001) of the by product in the sawmills of the three villages. The evidence in Ambato is different and in contrast with sawmills in Riobamba and Latacunga which shows a similar behavior in selling forestry waste periodically in the stages of primary and secondary transformation. This, therefore, is in a bid to take advantage of the opportunities for the development of new enterprises

DGAM METHODOLOGY TO DESIGN A KNOWLEDGE MANAGEMENT SYSTEM

The “Subdirección de Ingeniería y Desarrollo de Obras Estratégicas” of “Petróleos Mexicanos” determined that it was necessary to accelerate the evolution of knowledge within this organization, in order to achieve this purpose the “Subdirección de Ingeniería y Desarrollo de Obras Estratégicas” decided to develop and implement a Knowledge Management System. However, when trying to implement a Knowledge Management System, it was found that knowledge management models only provide generic sets of steps on how to carry out Knowledge Management, without specifying how to develop and implement Knowledge Management Systems in any organizations; hence the need of developing a Methodology that may suit the specific purposes required by the “Subdirección de Ingeniería y Desarrollo de Obras Estratégicas”, this four stages Methodology of Knowledge Management, is denominated DGAM. This nomination corresponds to each one of the four stages of the methodology: Determination, Generation, Accessibility and Maintenance

Estudio de ventajas y desventajas del policarbonato y trivex como materiales para lentes oftálmicos en usuarios de la provincia de Tungurahua, en el período noviembre 2006 - abril 2007

1. El problema 2. Metodología de investigación 3. Análisis de resultados 4. Conclusiones y recomendaciones.Este trabajo de investigación se ha realizado con el objetivo de establecer las razones por las que en la ciudad de Ambato, siendo tan comercial y en la que existen muchas ópticas dedicadas al cuidado de la visión, no ha tenido mucha acogida el policarbonato y el trivex como materiales para la fabricación de lentes. Así mismo se a querido contribuir con la búsqueda de las mejores opciones válidas para solucionar los múltiples problemas de visión que padece nuestra población.Pontificia Universidad Católica del Ecuador, Escuela de PsicologíaLicenciado en Optometrí

Métodos de control de los filtros

La tasa de filtración es directamente proporcional a la carga hidráulica disponible e inversamente proporcional a la resistencia total del filtro. Basándose en esta expresión hay cuatro condiciones básicas para describir el comportamiento de los filtros: 1) Carga hidráulica disponible constante y resistencia total del filtro variable. 2) Carga hidráulica disponible constante y resistencia total del filtro constante. 3) Carga hidráulica disponible variable y resistencia total del filtro constante. Carga hidráulica disponible variable y resistencia total del filtro variable. Las características de cada una de ellas, ventajas, desventajas y resultados experimentalesIngeniero CivilCuenc

Estudio de ventajas y desventajas del policarbonato y trivex como materiales para lentes oftálmicos en usuarios de la provincia de Tungurahua, en el período noviembre 2006 - abril 2007

1. El problema 2. Metodología de investigación 3. Análisis de resultados 4. Conclusiones y recomendaciones.Este trabajo de investigación se ha realizado con el objetivo de establecer las razones por las que en la ciudad de Ambato, siendo tan comercial y en la que existen muchas ópticas dedicadas al cuidado de la visión, no ha tenido mucha acogida el policarbonato y el trivex como materiales para la fabricación de lentes. Así mismo se a querido contribuir con la búsqueda de las mejores opciones válidas para solucionar los múltiples problemas de visión que padece nuestra población.Pontificia Universidad Católica del Ecuador, Escuela de PsicologíaLicenciado en Optometrí

Platyhypnidium aquaticum as bioindicator of metal and metalloid contamination of river water in a neotropical mountain city

Water contamination is a major environmental problem in many cities of the world. Most water contamination results from industry and human activities that generate toxic substances (e.g., metals). Rheophilic and aquatic mosses are found in lotic ecosystems, and their morphological and physiological traits are responsive to ecological and pollution gradients. Here we hypothesized that the native rheophilic moss Platyhypnidium aquaticum (A. Jaeger) M. Fleisch exposed to polluted waters can bioaccumulate greater amounts of metals, and a metalloid, than P. aquaticum exposed to pollution-free water. To this aim, we tested the bioindicator capacity of the aquatic P. aquaticum for 15 metals (Cd, Pb, Zn, Fe, K, Ca, Na, Mn, V, Co, Ba, Cr, Al, Sr, and Mg) and one metalloid (As), in twelve river samples coming from three urban and one control zone along the Zamora river in the city of Loja. When compared to the control, our results showed that P. aquaticum in the Southern, Central, and Northern zones of the city bioaccumulated higher concentrations of Ba, Cd, Co, Fe, Mg, Mn, Na, Sr, Zn, and the metalloid As. On the other hand, concentrations of Al, Ca, Cr, Pb, and V in P. aquaticum tended to be lower in the control zone, but these differences were not significant. We suggest that the presence of these contaminants may be related to water pollution (e.g., residual discharges and a lack of treatment systems) along urban zones of the river. We report for the first time the utility of P. aquaticum as a model species for development of long-term biomonitoring programs of water contamination in South America. Passive biomonitoring with P. aquaticum can be a simple and low-cost method to obtain reliable data of the current state of water contamination with metals and metalloids in tropical regions. © 2020 by the authors. Licensee MDPI, Basel, Switzerland

Efecto de Diferentes Dosis de Humus, Fitohormonas y Tiempos de Aplicación en la Producción Primaria del Pasto Arrhenatherum elatius

There is the need to provide an alternative source of food for cattle impulse to evaluate the effect of different doses of humus, phytohormones, and application times in the forage production of the Arrhenatherum elatius pasture. This has already been established in edaphoclimatic conditions of the Licto sector. However, it was implemented through 18 treatments, with 3 repetitions, using a completely random block design with a factorial arrangement (3x3x2). The variables analyzed were the plant height, basal cover, aerial cover, the time of occurrence of pre-flowering, and the production of green and dry matter. According to the results, the six evaluated variables did not show statistical differences in response to the independent effect due to the application of 4, 5, and 6 t • ha -1 of humus and 250 cc • ha -1 of gibberellins, cytokinins and ethylene respectively. On the other hand, the frequency of application showed a significant behavior for the variables; plant height, air cover, the time of occurrence of preflowering, and the production of green matter in 7 days. Finally, the interaction between the factors studied in this investigation showed statistical differences with 9 days of anticipation in the occurrence of the prefloración phase when applying 4 t • ha -1 of humus plus 250 cc • ha -1 of ethylene at 7 days of the equalization cut (H4-E-7). Thus, this is in relation to the 52 days of the treatment (H5-E-14), when placing 5 t • ha-1 of humus plus 250 cc • ha -1 of ethylene applied to the 14 days of the equalization cut. La necesidad de brindar una alternativa como fuente de alimento para el ganado impulso evaluar el efecto diferentes dosis de humus, fitohormonas y tiempos de aplicación, en la producción forrajera del pasto Arrhenatherum elatius cultivo ya establecido en condiciones edafoclimáticas del sector de Licto, donde se implementó la presente investigación mediante 18 tratamientos, con 3 repeticiones, utilizando un diseño de bloques completamente al azar con un arreglo factorial: 3x3x2. Las variables analizadas fueron la altura de planta, cobertura basal, cobertura aérea, el tiempo de ocurrencia de la prefloración, la producción de materia verde y seca. Según los resultados, las seis variables evaluadas, no mostraron diferencias estadísticas en respuesta al efecto independiente debido a la aplicación de 4, 5, y 6 t·ha -1 de humus y de 250 cc·ha -1 de giberelinas, citoquininas y etileno respectivamente. En cambio la frecuencia de aplicación, mostró un comportamiento significativo, para las variables; altura de planta, cobertura aérea, el tiempo de ocurrencia de la prefloración y producción de materia verde a los 7 días. Finalmente, la interacción entre los factores estudiados en esta investigación, mostró diferencias estadísticas con 9 días de anticipación en la ocurrencia de la fase de prefloración al aplicar 4 t·ha -1 de humus más 250 cc·ha -1 de etileno a los 7 días del corte de igualación (H4-E-7), en relación a los 52 días del tratamiento (H5-E-14), al colocar 5 t·ha -1 de humus más 250 cc·ha -1 de etileno aplicados a los 14 días del corte de igualación

Chemical Constituents of the Essential Oil from Ecuadorian Endemic Species Croton ferrugineus and Its Antimicrobial, Antioxidant and α-Glucosidase Inhibitory Activity

Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for wound healing and as an antiseptic. In this study, fresh Croton ferrugineus leaves were collected and subjected to hydrodistillation for extraction of the essential oil. The chemical composition of the essential oil was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against three Gram-positive bacteria, one Gram-negative bacterium and one dermatophyte fungus. The radical scavenging properties of the essential oil was evaluated by means of DPPH and ABTS assays. The chemical analysis allowed us to identify thirty-five compounds representing more than 99.95% of the total composition. Aliphatic sesquiterpene hydrocarbon trans-caryophyllene was the main constituent with 20.47 ± 1.25%. Other main compounds were myrcene (11.47 ± 1.56%), β-phellandrene (10.55 ± 0.02%), germacrene D (7.60 ± 0.60%), and α-humulene (5.49 ± 0.38%). The essential oil from Croton ferrugineus presented moderate activity against Candida albicans (ATCC 10231) with an MIC of 1000 μg/mL, a scavenging capacity SC50 of 901 ± 20 µg/mL with the ABTS method, and very strong antiglucosidase activity with an IC50 of 146 ± 20 µg/mL

Enantiomeric Composition, Antioxidant Capacity and Anticholinesterase Activity of Essential Oil from Leaves of Chirimoya (Annona cherimola Mill.)

Annona cherimola Mill. is a native species of Ecuador cultivated worldwide for the flavor and properties of its fruit. In this study, hydrodistillation was used to isolate essential oil (EO) of fresh Annona cherimola leaves collected in Ecuadorian Sierra. The EO chemical composition was determined using a non-polar and a polar chromatographic column and enantiomeric distribution with an enantioselective column. The qualitative analysis was carried out by gas chromatography coupled to a mass spectrometer and quantitative analysis using gas chromatography equipped with a flame ionization detector. The antibacterial potency was assessed against seven Gram-negative bacteria and one Gram-positive bacterium. ABTS and DPPH assays were used to evaluate the radical scavenging properties of the EO. Spectrophotometric method was used to measure acetylcholinesterase inhibitory activity. GC-MS analysis allowed us to identify more than 99% of the EO chemical composition. Out of the fifty-three compounds identified, the main were germacrene D (28.77 ± 3.80%), sabinene (3, 9.05 ± 1.69%), β-pinene (4, 7.93 ± 0.685), (E)-caryophyllene (10.52 ± 1.64%) and bicyclogermacrene (11.12 ± 1.39%). Enantioselective analysis showed the existence of four pairs of enantiomers, the (−)-β-Pinene (1S, 5S) was found pure (100%). Chirimoya essential oil exhibited a strong antioxidant activity and a very strong anticholinesterase potential with an IC50 value of 41.51 ± 1.02 µg/mL. Additionally, EO presented a moderate activity against Campylobacter jejuni and Klebsiella pneumoniae with a MIC value of 500 μg/mL