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Relación entre actividad enzimática y biomasa de ensambles fitoplanctónicos en el sistema pelágico
Iriarte,José L; Qui？ones,Renato A; González,Rodrigo R; Valenzuela,Cynthia P;
Investigaciones marinas , 2007, DOI: 10.4067/S0717-71782007000100006
Abstract: in environments with drastically fluctuating conditions, physiological and biochemical adaptations can be important for the structuration of phytoplankton assemblages. the objective of this study was to establish whether the enzymatic activity of the phytoplankton, an indicator of its dominant internal metabolism, is related to the autotrophic biomass. the geographic study area covered the south shetland islands (62°s), mejillones bay (22°s), and seno de reloncaví (41°30？s). samples were collected in the field at the selected sites for enzymatic analyses of the intermediary nitrogen metabolism (nitrate reductase, glutamine synthetase) and autotrophic biomass, as well as dissolved inorganic nutrient analyses. in terms of the size-fractionated enzymatic activity, nitrate reductase (bs reloncaví = -0.93; bb mejillones = -0.65) and glutamine synthetase (bs reloncaví = -0,79) activities decreased as the body size of the phytoplankton increased. these slopes, less than -1.0, indicate the relative importance of diatom-dominated phytoplanktonic assemblages in coastal waters rich in inorganic nitrogenated nutrients. elevated glutamine synthetase activity (gs) was detected during a bloom of a dinoflagellate species, suggesting that certain dinoflagellate species prefer reduced nitrogen forms (ammonium and urea) over nitrate or nitrite. the estimate, via enzymatic activity, of the f ratio with values > 0.5 and < 0.5 suggests, respectively, an important diatom contribution to new production (based on nitrate) as compared with the flagellate contribution, which is important to regenerated production (based on ammonium)
Enzyme activities of phytoplankton in the South Shetland Islands (Antarctica) in relation to nutrients and primary production Actividad enzimática en ensambles fitoplanctónicos en las Islas Shetland del Sur (Antártica) en relación a los nutrientes y producción primaria
JOSé L IRIARTE,RODRIGO R GONZáLEZ,RENATO A QUI？ONES,SUNG-HO KANG
Revista chilena de historia natural , 2006,
Abstract: Given the potential significance of enzyme activities as a link between internal metabolic pathways and environmental nutrients, we investigated the relationships of nitrate reductase (NR) and alkaline phosphatase (AP) with primary production and inorganic nutrients in South Shetland Islands, Antarctica. Enzymatic activities of the phytoplankton (0.7-210 μm), primary productivity, autotrophic biomass and inorganic nutrients were studied in the upper 100 m depth at nine stations during a cruise in the northwestern area of South Shetland Islands (Antarctica), during late austral spring (December 2000). NR activities fluctuated between 0 and 42.8 nmol L-1 h-1 (mean = 10.08 nmol L-1 h-1, SD = 10.42 nmol L-1 h-1), AP activities between 0.81 and 5.67 nmol L-1 h-1 (mean = 2.68 nmol L-1 h-1, SD = 0.95 nmol L-1 h-1). Stations with primary productivity (PP) and chlorophyll a greater than 2 mg C m-3 h-1 and 0.75 mg chlorophyll a L-1, respectively, presented higher enzymatic activities of nitrate reductase, alkaline phosphatase than those stations characterized by primary productivity and chlorophyll a less than 2 mg C m-3 h-1 and 0.17 mg chlorophyll a L-1, respectively. The AP specific activity was negatively correlated with orthophosphate concentrations lower than 2.0 μM, which indicates that the microplankton were under phosphate deficient environment condition. Our results indicated that NR specific activity was positively associated with autotrophic biomass and primary productivity estimates, giving evidence of the use of nitrate by phytoplankton as external nitrogen source in surface waters. In addition, high NR activities were positively correlated with NO3-, suggesting the occurrence of nitrate respiration in the well oxygenated surface waters of Antarctica Dada la potencial importancia de la actividad enzimática de ensambles fitoplanctónicos, como indicador de su metabolismo interno dominante respecto de los nutrientes, este estudio investigó las relaciones entre la nitrato reductasa (NR) y la fosfatasa alcalina (FA) con la producción primaria y nutrientes inorgánicos en las Islas Shetland del Sur, Antártica. Las variables de actividad enzimática del fitoplancton (0,7-210 μm), producción primaria, biomasa autotrófica y nutrientes inorgánicos fueron analizadas en nueve estaciones en los primeros 100 m de profundidad durante un crucero oceanográfico en el área noroeste de las Islas Shetland del Sur (Antártica), durante la primavera austral (diciembre 2000). Las actividades enzimáticas de NR fluctuaron entre 0 y 42,8 nmol L-1 h-1 (promedio = 10,08 nmol L-1 h-1
Relación entre actividad enzimática y biomasa de ensambles fitoplanctónicos en el sistema pelágico Relationship between enzymatic activity and biomass of phytoplankton assemblages in the pelagic system
José L Iriarte,Renato A Qui？ones,Rodrigo R González,Cynthia P Valenzuela
Investigaciones Marinas , 2007,
Abstract: En ambientes de condiciones fluctuantes y drásticas, las adaptaciones fisiológicas y bioquímicas pueden llegar a ser importantes en la estructuración de ensambles fitoplantónicos. El objetivo de este estudio fue establecer si la actividad enzimática de fitoplancton, como un indicador de su metabolismo interno dominante, se relaciona con la bio-masa autotrófica. Las áreas geográficas estudiadas correspondieron a: islas Shetlands del Sur (62°S), bahía de Mejillones (22°S) y seno de Reloncaví (41°30’S). En las áreas seleccionadas y mediante una aproximación de terreno, se colectaron muestras para análisis enzimático del metabolismo intermediario del nitrógeno (nitrato reductasa y glutamina sintetasa), biomasa autotrófica y análisis de nutrientes disueltos inorgánicos. En términos de la actividad enzimática fraccionada por tama o se observó una disminución de la actividad de nitrato reductasa (bS Reloncaví = -0,93; bB Mejillones = -0,65) y glutamina sintetasa (bS Reloncaví = -0,79) con el incremento del tama o corporal del fitoplancton. Estas pendientes, menores a -1,0, se alan la relativa importancia de ensambles fitoplanctónicos dominados por diatomeas en aguas costeras ricas en nutrientes inorgánicos nitrogenados. Durante el desarrollo de una floración de una especie de dinoflagelado se detectó una elevada actividad de glutamina sintetasa (GS), sugiriendo que ciertas especies de dinoflagelados prefieren las formas de nitrógeno reducido (amonio y urea) en comparación a nitrato o nitrito. La estimación, vía actividad enzimática, de la razón f con valores > 0,5 y < 0,5, sugiere la importante contribución de las diatomeas a la producción nueva (basada en nitrato) en comparación a los flagelados, los cuales contribuyen significativamente a la producción regenerada (basada en amonio), respectivamente In environments with drastically fluctuating conditions, physiological and biochemical adaptations can be important for the structuration of phytoplankton assemblages. The objective of this study was to establish whether the enzymatic activity of the phytoplankton, an indicator of its dominant internal metabolism, is related to the autotrophic biomass. The geographic study area covered the South Shetland Islands (62°S), Mejillones Bay (22°S), and Seno de Reloncaví (41°30’S). Samples were collected in the field at the selected sites for enzymatic analyses of the intermediary nitrogen metabolism (nitrate reductase, glutamine synthetase) and autotrophic biomass, as well as dissolved inorganic nutrient analyses. In terms of the size-fractionated enzymatic activity, ni
Organization and startup of the Gambia's new Community-Based Medical Programme
Chávez,José A.; Suárez,Lázaro V.; del Rosario,Odalis; Hechavarría,Suiberto; Qui？ones,Judith;
MEDICC Review , 2012, DOI: 10.1590/S1555-79602012000100009
Abstract: the shortage of health professionals in developing countries and especially in their poorest regions imperils the vision of health for all. new training policies and strategies are needed urgently to address these shortages. the gambia's new community-based medical programme is one such strategy.
Enzyme activities of phytoplankton in the South Shetland Islands (Antarctica) in relation to nutrients and primary production
IRIARTE,JOSé L; GONZáLEZ,RODRIGO R; QUI？ONES,RENATO A; KANG,SUNG-HO; SHIM,JAE H; VALENZUELA,CYNTHIA P;
Revista chilena de historia natural , 2006, DOI: 10.4067/S0716-078X2006000400009
Abstract: given the potential significance of enzyme activities as a link between internal metabolic pathways and environmental nutrients, we investigated the relationships of nitrate reductase (nr) and alkaline phosphatase (ap) with primary production and inorganic nutrients in south shetland islands, antarctica. enzymatic activities of the phytoplankton (0.7-210 μm), primary productivity, autotrophic biomass and inorganic nutrients were studied in the upper 100 m depth at nine stations during a cruise in the northwestern area of south shetland islands (antarctica), during late austral spring (december 2000). nr activities fluctuated between 0 and 42.8 nmol l-1 h-1 (mean = 10.08 nmol l-1 h-1, sd = 10.42 nmol l-1 h-1), ap activities between 0.81 and 5.67 nmol l-1 h-1 (mean = 2.68 nmol l-1 h-1, sd = 0.95 nmol l-1 h-1). stations with primary productivity (pp) and chlorophyll a greater than 2 mg c m-3 h-1 and 0.75 mg chlorophyll a l-1, respectively, presented higher enzymatic activities of nitrate reductase, alkaline phosphatase than those stations characterized by primary productivity and chlorophyll a less than 2 mg c m-3 h-1 and 0.17 mg chlorophyll a l-1, respectively. the ap specific activity was negatively correlated with orthophosphate concentrations lower than 2.0 μm, which indicates that the microplankton were under phosphate deficient environment condition. our results indicated that nr specific activity was positively associated with autotrophic biomass and primary productivity estimates, giving evidence of the use of nitrate by phytoplankton as external nitrogen source in surface waters. in addition, high nr activities were positively correlated with no3-, suggesting the occurrence of nitrate respiration in the well oxygenated surface waters of antarctica
EFFECTS OF DAYLENGTH AND SOIL HUMIDITY ON THE FLOWERING OF COFFEE COFFEA ARABICA L. IN COLOMBIA
Pe？a Qui？ones,Andrés Javier; Ramírez Builes,Víctor Hugo; Jaramillo Robledo,Alvaro; Rendón Sáenz,José Raúl; Arcila Pulgarín,Jaime;
Revista Facultad Nacional de Agronomía, Medellín , 2011,
Abstract: coffee flowering data were analyzed in order to explore the effect of two environmental variables that have been considered relevant for this process. pre-anthesis stage flowers were counted in coffee leaf-rust resistant crops at eight experimental stations (between 2°n and 11°n). likewise, climatic data were taken to generate a humidity soil index, whereas day longitude data were taken from the smithsonian meteorological tables. flowering data were compared with a sunshine index to understand better the effect of light on flowering. this data (flowering, soil humidity index and day length) were expressed in a monthly scale and analyzed using linear regression and cross-correlation functions. the main results show that there is a significant correlation between short days and high flowerings, whereas soil humidity (dry months) are related to the phenomenon, but to a lesser extent.
EFFECTS OF DAYLENGTH AND SOIL HUMIDITY ON THE FLOWERING OF COFFEE COFFEA ARABICA L. IN COLOMBIA EFECTO DE LA DURACIóN DEL DíA Y LA HUMEDAD DEL SUELO SOBRE LA FLORACIóN DEL CAFETO COFFEA ARABICA L. EN COLOMBIA
Andrés Javier Pe？a Qui？ones,Víctor Hugo Ramírez Builes,Alvaro Jaramillo Robledo,José Raúl Rendón Sáenz
Revista Facultad Nacional de Agronomía, Medellín , 2011,
Abstract: Coffee flowering data were analyzed in order to explore the effect of two environmental variables that have been considered relevant for this process. Pre-anthesis stage flowers were counted in coffee leaf-rust resistant crops at eight experimental stations (between 2°N and 11°N). Likewise, climatic data were taken to generate a humidity soil index, whereas day longitude data were taken from the Smithsonian Meteorological Tables. Flowering data were compared with a sunshine index to understand better the effect of light on flowering. This data (flowering, soil humidity index and day length) were expressed in a monthly scale and analyzed using linear regression and cross-correlation functions. The main results show that there is a significant correlation between short days and high flowerings, whereas soil humidity (dry months) are related to the phenomenon, but to a lesser extent. Con el objetivo de entender el efecto de las variables ambientales sobre el cultivo del café, se analizaron los datos de floración para explorar el efecto de dos variables que han sido reportadas como importantes en la floración de esta especie. Se contaron flores en etapa de pre-antesis en cafetales sembrados con variedades resistentes a roya en ocho estaciones experimentales entre 2°N y 11°N. A su vez, fueron tomados datos del clima para generar un índice de humedad del suelo, mientras que los datos de longitud del día se tomaron de las tablas meteorológicas del Smithsonian; para entender mejor el efecto de la luz sobre la floración, fueron comparados los datos de floración y un índice de brillo solar. Estos datos (floración, índice de humedad del suelo y longitud del día) se expresaron en escala mensual y se analizaron utilizando regresión lineal y funciones de correlación cruzada. Los resultados muestran que hay una correlación importante entre días cortos y altas floraciones, mientras que la humedad del suelo (meses secos) tienen una relación con el fenómeno, pero con menor correlación.
Determining cement ball mill dosage by artificial intelligence tools aimed at reducing energy consumption and environmental impact
Jorge L Qui？ones Ferreira,José P. Monteagudo Yanes,Julio R. Gómez Sarduy,Manuel E. Granado Rodríguez,Yudith Miranda Torres
- , 2013,
Abstract: Energy management systems can be improved by using artificial intelligence techniques such as neural networks and genetic algorithms for modelling and optimising equipment and system energy consumption. This paper proposes modelling ball mill consumption as used in the cement industry from field variables. The regression model was based on artificial neural networks for predicting the electricity consumption of the mill’s main drive and evaluating established consumption rate performance. This research showed the influence of the amount of pozzolanic ash, gypsum and clinker on a mill’s power consumption; the dose determined according to the model ensured minimum energy consumption using a simple genetic algorithm. The estimated savings potential from the proposed dose was 36 600 kWh / year for mill number 1, representing $5,793.78 / year and a 33,708 kg CO2 / year reduction in the environmental impact of gas left to escape
The Influence of Lipid and Proinflammatory Status on Maternal Uterine Blood Flow in Women With Late Onset Gestational Diabetes
Alejandro Figueroa-Qui？ones,Cristina López-Tinoco,Fernando Bugatto,Francisco M. Visiedo,José L. Bartha,José M. Vilar-Sánchez,Rafael Torrejón,Rocío Quintero-Prado
- , 2018, DOI: 10.1177/1933719117698576
Abstract: Gestational diabetes mellitus (GDM) is associated with increased proinflammatory cytokines and is also associated with adverse cardiovascular disease (CVD) outcomes later in life. We aim to evaluate the relationships between uterine arteries vascularization and endothelial dysfunction markers, proinflammatory cytokines, and glycemic and lipid profile in women with GDM. Fifty pregnant women were recruited at the third trimester of pregnancy for a prospective cohort study. They were classified into 2 groups: control and GDM. Comparisons of maternal plasma concentrations of endothelial dysfunction markers (vascular cell adhesion molecule 1, intercellular adhesion molecule 1, and plasminogen activator inhibitor 1), proinflammatory cytokines and mediators (interleukin 6 [IL-6], tumor necrosis factor α, vascular endothelial growth factor, placental growth factor, leptin, leukocyte count, and C-reactive protein), lipid profile, glucose, and glycosylated hemoglobin levels were performed. Mean uterine arteries Doppler pulsatility index (PI) was calculated and the relationships between the variables and PI were also analyzed. Women with GDM showed higher proinflammatory cytokines, however, endothelial dysfunction markers were similar in both groups. In the diabetic group, significant correlations were found between the mean uterine arteries PI and maternal IL-6 (r = .56, P = .01), triglycerides (r = .49; P = .03), total cholesterol/high-density lipoprotein cholesterol (HDL-c) ratio (r = .61; P = .006), glucose (r = .62, P = .005), and glycosylated hemoglobin (r = .48; P = .03). A negative significant correlation between mean uterine arteries PI and HDLc (r = ？.58; P = .02) was also found. The proinflammatory status, hyperlipidemia, and metabolic control correlate with uterine blood flow velocity waveforms in women with gestational diabetes
Retos de la entomología médica para la vigilancia en salud pública en Colombia: reflexión para el caso de malaria
Brochero,Helena; Qui？ones,Martha L.;
Biomédica , 2008,
Abstract: the relevance of the medical entomology was considered with respect to current framework of malaria control programs in colombia. a responsibility is indicated for balancing control efforts along with providing information on the malaria vectors. this knowledge must be acquired in order to focus the related activities that are required. the malaria control program must be based on results of local entomological surveillance, and the data must be in a form to give practical answers to questions regarding the control program. difficulties in undertaking the required studies are described, particularly regarding the taxonomic identification of colombian anopheles in colombia and which of these can be incriminated as malaria vectors.
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