Kinetics of zinc uptake and anatomy of roots and leaves of coffee trees as affected by zinc nutrition

Zinc (Zn) uptake kinetics and root and leaf anatomy were studied in coffee trees grown in nutrient solutions with or without Zn. Leaves and roots were sampled and cuts were made in the medium part of the leaves and in root tips and observed under an optical microscope. Plants grown without Zn showed an increase in root and in root stele diameter. There was also an increase in epidermis thickness and in the cross-sectional area of the cortex and stele due to Zn deficiency, but the diameter of xylem vessels was decreased. An increase in root cortex and stele diameter provided for an increased surface for nutrient uptake. Accordingly, C(min) was decreased from 13.8 to 3.4 mu mol L(-1) and V(max) increased from 0.50 to 2.1 mu mol cm(-2) h(-1) .

Phenomenological perspective on mathematics education

This is a philosophical essay on a phenomenological way to understand and to work out Mathematics Education. Its philosophical grounding is the Husserlian work, focusing on its key word "going to the things themselves" in order to keep us away from the theoretical educational truth, took as the unique one. We assume the attitude of being on the life-world with the students and Mathematics as a field of research and practice that show and express themselves through lived experiences and through language. We assume to be in search of understanding of education, learning and Mathematics, as we take care, consciously, of what we are doing and saying in the same movement of saying and doing it.

Oviposition pattern and within-season spatial and temporal variation of pre-dispersal seed predation in a population of Mimosa bimucronata trees

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Self-fertility and polyembryony in South American yellow trumpet trees (Handroanthus chrysotrichus and H. ochraceus, Bignoniaceae): a histological study of postpollination events

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anthocyanins and tannins in ozone-fumigated guava trees

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Nest associates and colony trees of the red-rumped cacique (Cacicus Haemorrhous, Icteridae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fruiting phenology of palms and trees in an Atlantic rainforest land-bridge island

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)