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Muniz-Ramirez A.,CINVESTAV | Perez-Gutierrez R.M.,Av Instituto Pol Nacional S N | Garcia-Baez E.,UPIBI IPN | Mota-Flores J.M.,Av Instituto Pol Nacional S N
Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas | Year: 2014

Two compounds from the hexane extract of seeds of Byrsonima crassifolia were isolated and their structures elucidated using extensive spectroscopic analyses. These compounds are derived from the new labdane diterpene Labda-17-(1) and the known antimicrobial Labda-8 (17)-(2). The present study was aimed to study the effect antimicrobial of novel diterpene 1 against bacterial pathogens showed a moderate activity with MIC values 18.79-70.12 μg/ml and a MBC ranging between 250-1000 μg/ml against all assayed microorganisms. © 2014. Source

Rodriguez V.,CINVESTAV | Valdez-Perez M.D.L.A.,CINVESTAV | Luna-Guido M.,CINVESTAV | Ceballos-Ramirez J.M.,CINVESTAV | And 5 more authors.
Applied Soil Ecology | Year: 2011

Liming or vermicomposting eliminates pathogens from wastewater sludge, but might affect CO2 and N2O emissions when added to soil. Soil incubated at 40%, 60%, 80% and 100% of its water holding capacity (WHC) was amended with limed or unlimed wastewater sludge, vermicompost or inorganic fertilizer, while emissions of N2O and CO2 and mineral N concentrations were monitored in aerobic incubation experiment for 7 days. Application of unlimed wastewater sludge significantly increased the emission of CO2 compared to the unamended soil, but not the other treatments except when unlimed wastewater sludge was added to soil incubated at 60% WHC. The emission of CO2, was generally largest in soil incubated at 60% WHC and lowest in soil incubated at 100% WHC. The emission of N2O after 1 day was significantly larger in soil amended with unlimed wastewater sludge compared to the other treatments, but not when soil was incubated at 100% WHC. The emission of N2O increased with increased soil water content. The concentration of NH4 + was largest in soil amended with limed or unlimed wastewater sludge and lowest in the unamended soil and soil water content had no clear effect on it. In soil incubated at 40%, 60% and 80% WHC, the largest amount of NO3 - was found in soil amended with inorganic fertilizer and vermicompost and the lowest in the soil amended with unlimed wastewater sludge. The concentration of NO3 - in soil decreased when the soil water content increased in all treatments, except in the soil amended with unlimed wastewater sludge. It was found that water content affected the emission of CO2 of N2O and the concentration of NO3 -, but not the amount of NH4 + and NO2 - in soil. Application of unlimed wastewater sludge increased the emissions of CO2 and N2O and the concentrations of NH4 +, but decreased the amount of NO3 - in soil. © 2011 Elsevier B.V. Source

Lopez-Munoz G.A.,Quimica Aromatica SA | Balderas-Lopez J.A.,UPIBI IPN
Thermochimica Acta | Year: 2014

Photothermal techniques were used to study thermal diffusivity, thermal effusivity, thermal conductivity and specific heat of folded and non-folded citrus essential oils and their corresponding terpenes; the latter are derivatives of the folding process. Experimental results show that thermal properties of all citrus essential oils are comparable. However due to a decrease on d-limonene and other monoterpenes with the folding process, thermal properties of folded citrus oils are higher than those for unfolded citrus oils. Moreover, thermal properties of various citrus terpenes are lower than those of folded and unfolded citrus oils. Analysis of variance (ANOVA) reveals significant differences (p < 0.05) among means for thermal data with the folding degree and fruit type for citrus oils. Valued obtained in this work, most of them not available in the literature thus far, together with values expected to emerge from future photothermal calorimetric experiments, might be used in the modelling and design of distillation columns, reboilers and heat exchangers all being parts of equipment used for citrus oils processing at industrial scale. © 2014 Elsevier B.V. Source

Valdez-Perez M.A.,CINVESTAV | Fernandez-Luqueno F.,CINVESTAV | Franco-Hernandez O.,UPIBI IPN | Flores Cotera L.B.,CINVESTAV | Dendooven L.,CINVESTAV
Scientia Horticulturae | Year: 2011

Wastewater sludge can be vermicomposted to increase its nutrient content and reduce pathogens. The effect of vermicompost wastewater sludge on soil characteristics and growth of bean plants (Phaseolus vulgaris L.) was compared with that of inorganic fertilizer, untreated sludge or sludge treated with lime to pH 12. Plants cultivated in vermicompost amended soil developed best while those amended with inorganic fertilizer least. Bean plants grown in the unlimed amended soil had the highest total N content of 3.97gkg-1, but only 6 active and 8 total nodules. Plants cultivated in unamended soil and added with inorganic fertilizer had >20 active and total nodules, but ≤2.12gNkg-1 dry plant. It was found that limed and unlimed sludge stimulated development of bean plants to a larger extent than those cultivated in inorganic fertilized soil or unamended soil in the greenhouse, but less than those cultivated in vermicompost amended soil. © 2011 Elsevier B.V. Source

Perez-Cruz J.H.,University of Guadalajara | Chairez I.,UPIBI IPN | De Jesus Rubio J.,Seccion de Estudios de Posgrado e Investigacion | Pacheco J.,Seccion de Estudios de Posgrado e Investigacion
IET Control Theory and Applications | Year: 2014

In this study, a neuro-controller with adaptive deadzone compensation for a class of unknown SISO non-linear systems in a Brunovsky form with uncertain deadzone input is presented. Based on a proper smooth parameterisation of the deadzone, the unknown dynamics is identified by using a continuous time recurrent neural network whose weights are adjusted on-line by stable differential learning laws. On the basis of this neural model so obtained, a feedback linearisation controller is developed in order to follow a bounded reference trajectory specified. By means of Lyapunov analysis, the boundedness of all the closed-loop signals as well as the weights and deadzone parameter estimations is rigorously proven. Besides, the exponential convergence of the actual tracking error to a bounded zone is guaranteed. The effectiveness of this scheme is illustrated by a numerical simulation. © The Institution of Engineering and Technology 2014. Source

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