19 resultados para functional diversity


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

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A strategy to measure bacterial functional redundancy was developed and tested with soils collected along a soil reclamation gradient by determining the richness and diversity of bacterial groups capable of in situ growth on selected carbon substrates. Soil cores were collected from four sites along a transect from the Jamari tin mine site in the Jamari National Forest, Rondonia, RO, Brazil: denuded mine spoil, soil from below the canopy of invading pioneer trees, revegetated soil under new growth on the forest edge, and the forest floor of an adjacent preserved forest. Bacterial population responses were analyzed by amending these soil samples with individual carbon substrates in the presence of bromodeoxyuridine (BrdU), BrdU-labeled DNA was then subjected to a 16S-23S rRNA intergenic analysis to depict the actively growing bacteria from each site, the number and diversity of bacterial groups responding to four carbon substrates (L-serine, L-threonine, sodium citrate, and or-lactose hydrate) increased along the reclamation-vegetation gradient such that the preserved forest soil samples contained the highest functional redundancy for each substrate. These data suggest that bacterial functional redundancy increases in relation to the regrowth of plant communities and may therefore represent an important aspect of the restoration of soil biological functionality to reclaimed mine spoils. They also suggest that bacterial functional redundancy may be a useful indicator of soil quality and ecosystem functioning.

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Previous studies on legume pulvini suggest that the vascular system plays an important role in the redistribution of ions and transmission of stimuli during leaf's movements. However, the number of anatomical and ultrastructural studies is limited to few species. The aim of this paper is to investigate the structure and cellular features of the pulvinus vascular system of nine legume species from Brazilian cerrado, looking for structural traits pointing to its participation in the leaf's movements. Samples were excised from the medial region of opened pulvinus of Bauhinia rufa, Copaifera langsdorffii, Senna rugosa (Caesalpinioideae), Andira humilis, Dalbergia miscolobium, Zornia dilphylla (Faboideae), Mimosa rixosa, Mimosa flexuosa and Stryphnodendron polyphyllum (Mimosoideae), and were prepared following light microscopy, transmission electron microscopy and histochemical standard techniques. The vascular system occupies a central position, comprises phloem and xylem and is delimited by a living sheath of septate fibers in all the species studied. This living cells sheath connects the cortex to the vascular tissues via numerous plasmodesmata. The absence of fibers and sclereids, the presence of phenolic idioblasts and the abundance and diversity of protein inclusions in the sieve tube members are remarkable features of the phloem. Pitted vessel elements, parenchyma cells with abundant cytoplasm and living fibriform elements characterize the xylem. The lack of lignified tissues and extensive symplastic continuity by plasmodesmata are remarkable features of the vascular system of pulvini of the all studied species. (c) 2007 Elsevier Ltd. All rights reserved.

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Introduction: Psychogenic dysphonia is a functional disorder with variable clinical manifestations.Objective: To assess the clinical and vocal characteristics of patients with psychogenic dysphonia in a case series.Methods: The study included 28 adult patients with psychogenic dysphonia, evaluated at a University hospital in the last ten years. Assessed variables included gender, age, occupation, vocal symptoms, vocal characteristics, and videolaryngostroboscopic findings.Results: 28 patients (26 women and 2 men) were assessed. Their occupations included: housekeeper (n = 17), teacher (n = 4), salesclerk (n = 4), nurse (n = 1), retired (n = 1), and psychologist (n = 1). Sudden symptom onset was reported by 16 patients and progressive symptom onset was reported by 12; intermittent evolution was reported by 15; symptom duration longer than three months was reported by 21 patients. Videolaryngostroboscopy showed only functional disorders; no patient had structural lesions or changes in vocal fold mobility. Conversion aphonia, skeletal muscle tension, and intermittent voicing were the most frequent vocal emission manifestation forms.Conclusions: In this case series of patients with psychogenic dysphonia, the most frequent form of clinical presentation was conversion aphonia, followed by musculoskeletal tension and intermittent voicing. The clinical and vocal aspects of 28 patients with psychogenic dysphonia, as well as the particularities of each case, are discussed. (C) 2014 Associacao Brasileira de Otorrinolaringologia e Cirurgia Cervico-Facial. Published by Elsevier Editora Ltda. All rights reserved.