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Search Results: 1 - 10 of 193887 matches for " Emma;Cervantes-Díaz "
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Alternativas de control en la pudrición radical de cebolla para el Valle de la Trinidad, Baja California
Pulido-Herrera, Armando;Zavaleta-Mejía, Emma;Cervantes-Díaz, Lourdes;Grimaldo-Juárez, Onécimo;
Revista mexicana de ciencias agrícolas , 2012,
Abstract: onion's root rot is the most important disease in the trinidad valle, baja california, mexico. in orderto evaluate strategies to control this disease, three experiments were conducted during 2007, 2008 and 2009. in experiment i (2007) the treatments were: 1) thiophanate methyl; 2) smicobac (trichoderma+bacillus sp. + azospirillum sp. + pseudomonas sp.); 3) cattle manure (eb); 4) waste of onion (rc); 5) clear plastic solarization (spt); 6) black plastic solarization (spn); 7) spt + eb; 8) spt + cr; 9) spn + eb; 10) spn + so; 11) trichodef (trichoderma harzianum); and 12) control. in experiment ii (2008), treatments were the same except treatment 2, replaced by a protective agent (plant extracts), and in experiment iii (2009) the treatments were: 1) spt + sheep manure (eo); 2 ) spn + eo; 3) spt; 4) spn; 5) biological control (trichoderma spp.); and 6) chemical control (2 - (thiocyanomethylthio) benzothiazole 30%. the results indicated that the clear plastic solarization treatments with or without organic amendments showed significant increases (p<0.05) from 22 to 34%yield and diameterwith respect to biological and chemical control, but the latter two treatments in the incidence and severity decreasedsignificantly (p<0.05 ), so that the clearplastic solarization and biological control, are viable alternatives to control root rot in onion crops in baja california, mexico.
Alternativas de control en la pudrición radical de cebolla para el Valle de la Trinidad, Baja California Control Alternatives for Onion root rot in the Trinity Valley, Baja California
Armando Pulido-Herrera,Emma Zavaleta-Mejía,Lourdes Cervantes-Díaz,Onécimo Grimaldo-Juárez
Revista mexicana de ciencias agrícolas , 2012,
Abstract: La pudrición radical en cebolla es la enfermedad más importante en el Valle de la Trinidad, Baja California, México. Con el propósito de evaluar estrategias de control para la enfermedad se realizaron tres experimentos durante 2007, 2008 y 2009. En el experimento I (2007) los tratamientos fueron: 1) Tiofanato metílico; 2) Smicobac (Trichoderma + Bacillus sp. + Azospirillum sp. + Pseudomonas sp.); 3) estiércol de bovino (EB); 4) residuos de cebolla (RC); 5) solarización plástico transparente (SPT), 6) solarización plástico negro (SPN); 7) SPT + EB; 8) SPT + RC; 9) SPN + EB; 10) SPN + RC; 11) Trichodef (Trichoderma harzianum);y 12)testigo. En el experimento II (2008), los tratamientos fueron los mismos excepto el tratamiento 2, sustituido porprotector (extractos vegetales); y en el experimento III (2009) los tratamientos fueron: 1) SPT + estiércol de ovino (EO); 2) SPN + EO; 3) SPT; 4) SPN; 5) control biológico (Trichoderma spp.); y 6) control químico (2- (tiocianometiltio) benzotiazol 30%. Los resultados indicaron que los tratamientos solarización plástico transparente con o sin enmiendas orgánicas, presentaron incrementos significativos (p≤ 0.05) de 22 a 34% en el rendimiento y diámetro del bulbo con respecto al control biológico y químico; sin embargo, en estos dos últimos tratamientos la incidencia y severidad se redujo significativamente (p≤ 0.05), por lo que la solarización con plástico transparente y el control biológico, son alternativas viables para el control de la pudrición radical en cultivos de cebolla en Baja California, México. Onion's root rot is the most important disease in the Trinidad Valle, Baja California, Mexico. In orderto evaluate strategies to control this disease, three experiments were conducted during 2007, 2008 and 2009. In experiment I (2007) the treatments were: 1) Thiophanate methyl; 2) Smicobac (Trichoderma+Bacillus sp. + Azospirillum sp. + Pseudomonas sp.); 3) cattle manure (EB); 4) waste of onion (RC); 5) clear plastic solarization (SPT); 6) black plastic solarization (SPN); 7) SPT + EB; 8) SPT + CR; 9) SPN + EB; 10) SPN + SO; 11) Trichodef (Trichoderma harzianum); and 12) control. In Experiment II (2008), treatments were the same except treatment 2, replaced by a protective agent (plant extracts), and in experiment III (2009) the treatments were: 1) SPT + sheep manure (EO); 2 ) SPN + EO; 3) SPT; 4) SPN; 5) biological control (Trichoderma spp.); and 6) chemical control (2 - (thiocyanomethylthio) benzothiazole 30%. the results indicated that the clear plastic solarization treatments with or without organic amendments sho
Detección de geminivirus asociados a la alstroemeria (alstroemeria l.) En villa guerrero, estado de México
Cervantes-Díaz,Lourdes; Zavaleta-Mejía,Emma; Rojas-Martínez,Reina Isabel; Alanís-Martínez,Iobana; Ochoa-Martínez,Daniel Leobardo; Valadez-Moctezuma,Ernestina; Grimaldo-Juárez,Onécimo;
Interciencia , 2009,
Abstract: in alstroemeria (alstroemeria l.) plantations located in villa guerrero, mexico state, plants with symptoms similar to those induced by geminivirus in other horticultural crops have been detected. in addition, the presence of whiteflies, which are considered the most efficient vectors of these viruses, has been observed in these plantations. the goal of this work was to detect the presence of this geminivirus species in alstroemeria plants. by means of pcr analysis using primers motcp2118/motcp2123, a fragment of ~600pb similar to the amplicon obtained from phyvv-infected positive control was amplified only from symptomatic plants. nicotiana glutinosa, n. benthamiana, n. rustica, n. tabacum var. xanthi and datura stramonium plants were inoculated by bombardment with total dna obtained from symptomatic alstroemerias and positive to phyvv by means of pcr. inoculated plants showed mild mosaics and deformation of leaves, whereas in the leaves of capsicum annum plants, mosaics, vein necrosis and blisters were observed. using dna from these plants as template in pcr, amplicons corresponded to phyvv were also obtained; however, in bombarded monocotyledons, including alstroemeria, this fragment was not detected. the sequence of oligonucleotides from the pcr products showed 98% homology to phyvv geminivirus. even though symptoms presented by alstroemeria plants in the field were not reproduced, the presence of a geminivirus similar to phyvv in tissue of symptomatic plants was evidenced through pcr.
Respuesta fisiológica de Euglena gracilis al estrés por cobre
García, David Cervantes;González-Mendoza, Daniel;Cervantes-Díaz, Lourdes;Trejo, Adriana Morales;Juárez, Onecimo Grimaldo;Zamora-Bustillos, Roberto;
Química Nova , 2011, DOI: 10.1590/S0100-40422011000700020
Abstract: the objective of this study was to evaluate the toxic effect of cu2 + in the physiological development of e. gracilis. the results showed that e. gracilis had an effect on the dose-dependent growth to the concentration of metal. the exposure of e. gracilis metal at doses of 0.8 and 1.6 mm of cu2+ showed a significant negative effect on the stability of dna and photosynthetic pigments involved in capturing light in the antenna complex after 144 h of exposure to the metal.
Hongos ectomicorrícicos y la tolerancia a la salinidad en plantas
AGUILAR-AGUILAR,SELENE; PéREZ-MORENO,JESúS; FERRERA-CERRATO,RONALD; GRIMALDO-JUáREZ,ONéCIMO; CERVANTES-DíAZ,LOURDES; GONZáLEZ-MENDOZA,DANIEL;
Revista chilena de historia natural , 2009, DOI: 10.4067/S0716-078X2009000100011
Abstract: the process of salinization of the soil is a widespread problem at the global level. in this sense, ectomycorrhizal fungi have an important role in the recovery of forest soil, as it involves a number of cellular mechanisms that may contribute to the salinity tolerance in plants that inhabit temperate and boreal forests. the participation of ectomycorrhizal fungi on the salinity tolerance involves the ion-homeostasis regulation, improving uptake water and inducing specific gene in roots colonized. likewise ectomycorrhizal fungi can stimulate the presence of osmolytes as proline, sugars and polyols that contribute to the protection of plant cells. additionally, these organisms stimulate the synthesis of glutathione and antioxidant enzymes involved in the decrease of reactive oxygen species. this review provides an overview of participation of ectomycorrhizal fungi in the salinity tolerance in plants.
Estrategias migratorias de las mujeres ecuatorianas en Sevilla: Acumulación de capital social en tiempos de crisis
Emma MARTíN DíAZ
Migraciones internacionales , 2012,
Abstract: Este artículo se centra en el análisis de las estrategias de las mujeres ecuatorianas en Sevilla. En concreto, veremos cómo se implementa la estrategia de acumulación de activos en la reconstrucción y resignificación de las redes sociales de las mujeres migrantes, analizando su evolución desde un contexto de partida reconocido como de crisis (término polisémico que incluye no sólo la crisis financiera de 1999, sino una crisis de reproducción social de las estructuras patriarcales y las relaciones personales) hasta el contexto actual de crisis económica en las sociedades de destino. Estas estrategias incluyen la implementación de recursos --materiales, sociales, políticos y simbólicos-- y su gestión por unas redes "en femenino", que se han ido reconstruyendo y resignificando a medida que se desarrolla el proceso migratorio.
Stability of Teleoperation Systems for Time-Varying Delays by Neutral LMI Techniques
Emma Delgado,Miguel Díaz-Cacho,Antonio Barreiro
Mathematical Problems in Engineering , 2012, DOI: 10.1155/2012/467629
Abstract:
Stability of Teleoperation Systems for Time-Varying Delays by Neutral LMI Techniques
Emma Delgado,Miguel Díaz-Cacho,Antonio Barreiro
Mathematical Problems in Engineering , 2012, DOI: 10.1155/2012/467629
Abstract: This paper investigates the delay-dependent stability of a teleoperation system based on the transparent Generalized Four-Channel control (G-4C) scheme under time-varying communication delays. To address stability we choose here a primitive result providing a Linear Matrix Inequalities (LMIs) approach based on Lyapunov-Krasovskii functionals. Firstly, the scheme is modeled as the neutral-type differential-delayed equation; that is, the delay affects not only the state but also the state derivative. Secondly, we apply a less conservative stability criteria based on LMIs that are delay dependent and delay's time-derivative dependent. The reason is that, for better performance in the case of small delays, we must accept the possibility that stability is lost for large delays. The approach is applied to an example, and its advantages are discussed. As a result, we propose to modify the values of standard controllers in G-4C defining the -4C scheme, which introduces a tuning factor to increase in practical conditions the stable region fixing the desired bounds on time-varying delay, with the particularity of maintaining the tracking properties provided by this transparent control scheme. The simulation results justify the proposed control architecture and confirm robust stability and performance. 1. Introduction A teleoperation system consists of master and slave mechanical systems where the master is directly manipulated by a human operator and the slave, operating in a remote environment, is designed to track the master closely. The main aspects in the analysis and synthesis of these systems are stability and transparency, meaning this last condition the grade of achievement of direct action ideal situation of the operator on the remote environment. In practice, there is a compromise between these two goals mainly due to the presence of time delays generated by the communication channel [1]. Under this compromise, many control schemes for teleoperation have been proposed in the last years. A first comparative study among them presented by Arcara and Melchiorri can be seen in [2]. Following this work, as stability is concerned, the teleoperation schemes are classified in intrinsically stable schemes (passivity based), and delay-dependent stable schemes. Therefore, in the initial works, concerning constant delay, the stability is addressed by means of frequency Laplace or passivity techniques, applied to linear time invariant master-slave two-port systems [1–5]. On the other side, related with transparency properties, the most successful control scheme in
Esperanza de vida saludable asociada a la diabetes en Cuba: a?os 1990 y 2003
Domínguez Alonso,Emma; Seuc Jo,Armando; Díaz Díaz,Oscar; Aldana Padilla,Deysi;
Revista Cubana de Endocrinolog?-a , 2010,
Abstract: objective: to identify the possible differences in integral burden (combining mortality and morbidity) of diabetes among the age groups, provinces, sexes, as well as to assesses its behavior in the time (years 1990 and 2003). methods: authors used a healthy life expectancy indicator, particularly, an alternative considering the mortality and the morbidity as specific diseases (in this case, diabetes). to estimate the indicator we achieved a common life expectancy (no-adjusted) from a life table, considering only the diabetes mortality. the life expectancy thus obtained was adjusted from morbidity (prevalence and severity) due this condition. we estimated the indicator by sex, age groups, and provinces and also for 1990 and 2003. a cluster analysis was made to resume and to integrate the results by provinces. results: most of results are consistent for cuba and almost as the whole of provinces for both years. there was a higher affectation of female sex (e.g.: cuba, 2003, group aged under one, healthy life expectancy of 99,17 in men versus 98.67 in women), increase of mortality contribution with the age achieving the higher figures in 60-64 age group. the course of 1990 to 2003 is rising for life expectancy and mortality contribution and descending for a healthy life expectancy (e.g. cuba: women aged under one from 99.59 to 99.76; from 0.7 to 1.09 %, and from 98.89 to 98.76, respectively). we identified provinces with a higher impact in terms of healthy life expectancy including: ciudad de la habana, la habana, matanzas (in 1990) and camaguey (in 2003). conclusions: affectation due to diabetes in terms of a healthy life expectancy increased during national study period, despite the decrease of mortality contribution.
Esperanza de vida ajustada por diabetes
Seuc,Armando H.; Domínguez,Emma; Díaz Díaz,Oscar;
Revista Cubana de Endocrinolog?-a , 2003,
Abstract: diabetes is one of the non-conveyable chronic diseases of higher impact due to its morbidity and mortality. in cuba, this impact on morbidity has not been quantified into a unique index that covers relative severity of diabetes and its complications. disability-adjusted life expectancy (dale) is a relatively recent indicator that allows quantifying the effect of morbidity from any disease, particularly diabetes and its complications, on life expectancy. this paper estimated dale for diabetes for the years 1990, 1995 and 2000, which facilitated the comparative study of the impact of morbidity from diabetes (and its complications) between men and woman in the course of these three years. it was observed that the negative impact of morbidity from diabetes and its sequelae on life expectancy increased throughout the whole studied period, but this increase was more remarkable in women who showed a reduction rate in life expectancy due to this disease higher than that of men in the 3 analyzed years. the morbidity burden from diabetes and its sequelae increased with the age in the three years under study.
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