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Copyright of Digital Education Review is the property of University of Barcelona, Virtual Teaching & Learning Research Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of the exposure to copper in metal bioaccumulation capacity in cells from Euglena gracilis was evaluated in this study. Metal accumulation measured with the X-ray fluorescence (XRF) technique showed that the accumulation of Cu+2 in E. gracilis was dose dependent and was significantly increased in cells treated with 0.4 and 0.8 mM of Cu+2 with respect to control. The presence of an accumulation strategy in E. gracilis that could involve the participation of a number of multiple processes, such as production of vacuoles, is not discarded. Future studies should be oriented to evaluate the potential for bioaccumulation of E. gracilis to be applied in bioremediation of aquatic systems programs. [ABSTRACT FROM AUTHOR]

Copyright of Espacio, Tiempo y Forma: Serie II, Historia Antigua is the property of Editorial UNED and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nomadas (01217550) is the property of Universidad Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pollen grains of two genera and twelve species (one with two varieties) belonging to Mexican members of the family Cistaceae are studied and illustrated. The taxa are: Helianthemum argenteum Hemsl., H. chihuahuense S. Wats., H. concolor (Riley) González-Ortega, H. coulteri S. Wats., H. glomeratum Lag., H. nutans Brandegee, H. patens Hemsl., H. pringlei S. Wats., H. pugae Calderón, H. scoparium var. aldersonii (Greene) Munz, H. scoparium var. vulgare Jepson, Lechea mucronata Raf. and L. tripetala (Moc. et Sessé) Britton. According to pollen characters two taxa can be differentiated, coinciding with the separation of Helianthemum and Lechea. At the species level within each genus, the species are very similar. All are reticulate and the diameter of lumina varies between 1 and 3 μ in Helianthemum, while that of Lechea measures less than 1 μ. The palynological characters of the Mexican plants considered as Helianthemum do not coincide with those refered in literature for the Old World species of that genus and differ also substantially from those reported for the members of Halimium and Crocanthemum. [ABSTRACT FROM AUTHOR]

Pollen grains morphology of 7 families and 21 species from the Estación de Biología Chamela, Jalisco, of the Universidad Nacional Autónoma de México is studied and illustrated. The following taxa are included: Amaranthaceae represented by Achyranthes aspera L., Alternanthera cf. pycnantha (Benth.) Standl., Amaranthus retroflexus L., Chamissoa altissima (Jacq.) H.B.K., Froelichia interrupta (L.) Moq., Gomphrena decumbens Jacq., Iresine calea (Ibáñez) Standl., I. interrupta Benth. and Lagrezia monosperma (Rose) Standl.; Combretaceae by Combretum fruticosum (Loefl.) Stuntz and C. mexicanum (L.) Mow.; Loasaceae by Gronovia scandens L. and Mentzelia aspera L.; Loganiaceae by Strychnos cf. brachistantha Standl.; Martyniaceae by Martynia annua L.; Papaveraceae by Argemone ochroleuca subsp. ochroleuca Sweet; Tiliaceae by Heliocarpus pallidus Rose, Luehea candida (DC.) Mart. and Triumfetta acracantha Hochr.; Violaceae by Hybanthus attenuantus (Humb. & Bonpl.) G. K. Schulze, H. mexicanus Ging. and H. serrulatus Standl. The observations of pollen grains were carried out with scanning electron microscopy and light microscopy. Taxonomic keys for separation of genera and species of pollen grains in the Amaranthaceae, Loasaceae and Tiliaceae are included. [ABSTRACT FROM AUTHOR]

Pollen grains morphology of the following members of the flora of the Valley of Mexico is studied and illustrated: family Aceraceae, represented by Acer negundo L. and A. negundo var. mexicanum (DC.) Standl. & Steyerm.; family Aquifoliaceae by liex tolucana Hemsl.; family Geraniaceae with 2 genera and 11 species: Erodium cicutarium (L.) L'Hérit., E. moschatum (L.) L'Hérit., Geranium aristisepalum Moore, G. bellum Rose, G. cruceroense Knuth, G. latum Small, G. lilacinum Knuth, G. lozani Rose, G. potentillaefolium, DC., G schiedeanum Schl. y G. seemannii Peyr. Pollen grains of Geraniaceae family can be separated on generic level, but differentiation of species is very difficult, in the genus Erodium it is not possible to separate the two species studied and, in Geranium differences in the ornamentation allow the recognition of two pollen groups: Geronium lozani, G. potenlillaefolium, G. seemannii, G. schiedeanum, G. bellum, G. cruceroense and G. litacinum have pollen grains with baculae of uniform size; in G. aristisepalum and G. latum the baculae are of two different sizes. The following families are also treated: Resedaceae, represented by Reseda luteola L.; Sabiaceae, by Meliosma dentata (Liebm.) Urban; and Saxifragaceae, by Heuchera orizabensis Hemsl., Philadelphus mexicanus Schl., Ribes affine H.B.K., R. ciliatum H.B.K. and R. microphyllum H.B.K. In the Ssxifragaceae, pollen grains of Heuchera and Philadelphus are similar but those of Ribes are very different. The observations of pollen grains were carried out with SEM and ML. [ABSTRACT FROM AUTHOR]

Pollen grain morphology of the families Acanthaceae, Vitaceae and Violaceae of the flora of the Valley of México is studied and illustrated: the first family is represented by Acanthus mollis L., Anisacanthus quadrifidus (Vahl) Standl., Dicliptera peduncularis Nees, Dyschoriste decumbens (Gray) O. Ktze., D. microphylla (Cav.) O. Ktze., Justicia furcata Jacq., Pseuderanthemum praecox (Benth.) Leonard, Ruellia bourgaei Hemsl., R. lactea Cav., R. speciosa (Nees) Lindau, Stenandrium dulce (Cav.) Nees and Tetramerium nervosum Nees. Of the Vitaceae, pollen morphology of Cissus sicyoides L. and Vitis bourgeana Planchon, is described. Palynological keys for separation of genera and species of the Acanthaceae and Vitaceae are included. The Violaceae comprehend Hybanthus verticillatus (Ort.) Baill., H. verbenaceus (H.B.K.) Loes., Viola beamanii Calderón, V. ciliata Schl., V. hemsleyana Calderón, V. hookeriana H.B.K., V. humilis H.B.K., V. painteri Rose et House and V. umbraticola H.B.K. Pollen grains of this family are very uniform and therefore it is not possible to separate the taxa by palynological characteristics. Observations of pollen grains were carried out with light microscope and scanning electronic microscope. [ABSTRACT FROM AUTHOR]

Pollen grain morphology of 9 families and 10 species of the tropical deciduous forest of the Biological Station of Chamela, Jalisco, belonging to the Universidad Nacional Autónoma de México was studied. These taxa are: Achatocarpaceae represented by Achatocarpus gracilis H. Walt.; Basellaceae, Anredera scandens (L.) Moq.; Caricaceae, Jarilla heterophylla (Cav.) Rusby and Jacaratia mexicana A. DC.; Chrysobalanaceae, Couepia polyandra (Kunth) Rose; Julianiaceae, Amphipterygium adstringens (Schlecht.) Schiede; Moringaceae, Moringa oleifera Lam.; Opiliaceae, Agonandra racemosa (DC.) Standl.; Plumbaginaceae, Plumbago scandens L. and Simaroubaceae, Recchia mexicana Moc. & Sessé. Pollen grains of the families Basellaceae, Caricaceae, Chrysobalanaceae, Moringaceae and Opiliaceae were studied with SEM. A key for genera and species of the Caricaceae, based on pollen grains characteristics, is also included. [ABSTRACT FROM AUTHOR]

The pollen morphology of the Polygalaceae of the Valley of Mexico is studied using LM and SEM, for all seven species: Monnina ciliolata DC., Polygala alba Nutt., P. appressipilis Blake, P. compacta Rose, P. myniltoides Willd., P. mexicana Moc. and P. subalata S. Wats. Pollen grains belonging to the family do not present great differences in ornamentation, form or size at the generic or specific levels: nevertheless, the taxa studied can be divided into two groups based on furrow number. Polygala alba, P. mexicana and P. subalata all have 8 to 10 furrows, while Monnina ciliolata, P. appressipilis, P. compacta and P. myrtiltoldes have 14 to 20. Comparing the taxonomic studies in Polygala with the present pollen study, it is observed that the species with 8 to 10 furrows correspond to subgenus Orthopolygala {subg. Polygala) and the species with 14 to 20 furrows to subgenus Hebecarpa (Blake, 1916). [ABSTRACT FROM AUTHOR]

When finely analyzing complex decisions, it is necessary to use several methods of operational research, decision theory in particular. However, these normally cannot handle election tie-breakers or disagreement in group decisions for certain reasons. In this article, we extend the range of the methodological scheme of the analytical hierarchy process (AHP) to address problems in reaching consensus among experts. First, we verify that it is a technique that guarantees the necessary set of preferences in an expert judgment; then we apply a prioritization procedure with the geometric mean to verify, reach and improve the level of consensus of the group via this technique. Finally, through a case of application in the industrial logistics sector, the scheme developed is illustrated, reaching positive results that indicate its effectiveness and applicability within the field of the Decision Theory. [ABSTRACT FROM AUTHOR]