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  • Author or Editor: A. González-Pérez x
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The flora of lomas del seminario reserve was studied. It includes 456 taxa which distribute in 91 families and 262 genera. The phytogeographical affinities for farmilies concern 40.7% cosmopolitan, 18.7% temperate-tropical and 17.6% tropical, meanwhile the genera denote 30.2% tropical, 18.33% temperate, 16.06% American, 12.2% cosmopolitan and 12.03% tropical-temperate. Also 21 new records for the flora of this zone, including the valley of Mexico, are reported

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Acta Biologica Hungarica
Authors: Ana Zamora-Perez, Claudia Camacho-Maga?a, Belinda Gómez-Meda, María Ramos-Ibarra, Cecilia Batista-González, and G. Zú?iga-González

The objective of the work was to characterize the presence of spontaneous micronucleated erythrocytes (MNES) from peripheral blood of bottlenose dolphins (Tursiops truncatus) to evaluate the possibility to use this species as potential bioindicator of genotoxic compounds. Forty-eight blood samples from 12 bottlenose dolphins were obtain from three Mexican dolphinariums, and from 10 dolphins was possible to obtain more than one sample at different sampling times. Smears were processed and observed with an epifluorescence microscope. The average of MNES and polychromatic erythrocytes (PCE) from the 48 samples was 24.3±6.1 MNES/10,000 total erythrocytes (TE), and 9.1±5.5 PCE/1,000 TE. MNES and PCE number did not show differences between gender and age. No variations in the MNES values of the bottlenose dolphins that were sampled more than one occasion were found. Comparisons among dolphinariums revealed differences in MNES frequency, with the highest significant frequency observed in dolphins from dolphinarium “A” (26.0±5.9 MNES/10,000 TE) than dolphinarium “B” (19.5±3.1 MNES/10,000 TE) (p<0.05) and dolphinarium “C” (18.6±3.5 MNES/10,000 TE) (p<0.007). The presence of MNES and PCE in the bottlenose dolphin may provide a useful marine mammal model to detect DNA damage by means of micronuclei test in peripheral blood erythrocytes to evaluate genotoxicity and cytotoxicity expositions.

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Journal of Thermal Analysis and Calorimetry
Authors: J. Galán, J. Del Castillo, A. González-Pérez, V. Fuentes-Vázquez, and J. Rodríguez

Abstract  

The specific conductivities of dodecylpyridinium chloride have been determinated in water-butanol/pentanol/hexanol solutions in the temperature range of 10 to 35C, and butanol, pentanol and hexanol concentrations up to 0.05 mol kg–1. From these data the temperature dependence of the critical micelle concentration, (cmc), was determined. The molar fraction of alcohol in the micelle was estimated using the theory suggested by Motomura et al. for surfactant binary mixtures. The standard Gibbs free energy of solubilization of alcohols in the micelles was worked out using the phase separation model.

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Abstract  

Five types of Cuban concretes and their main components (mineral aggregates and cements) were analyzed for uranium, thorium, radium, potassium and radon (220Rn,222Rn) using -spectroscopy, track registration methods and neutron activation analysis. Comparative evaluation of different concretes, aggregates and two types of cements concerning their natural radioactivity is presented.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: N. Alberro Macias, I. Pupo González, L. Valcárcel Rojas, D. Frías Fonseca, J. R. Estévez Álvarez, D. López Sánchez, A. Montero Álvarez, D. Simón Pérez, M. A. Isaac Tejera, and J. F. Pérez Oliva

Summary  

The quality of the potable and purified for haemodialysis waters used in the National Institute of Nephrology was evaluated since 2002 up to now. A total of 20 chemical components were analyzed. The analytical results were compared with the admissible maximum concentrations according to the Cuban Standard NC 92-02:85 for potable water and with the Spanish Standard UNE 111-301-90, related to the quality of water for use in haemodialysis. The quality of both types of water was found to comply with the Standards regulations. The CEADEN analytical chemistry laboratory operates a quality management system since 1992, that was credited according to ISO/IEC 17025 requirements.

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