12 research outputs found

    Mycorrhizas in South American Anthropic Environments

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    The agricultural expansion has leaded to increase the irrigated cropland area and the use of fertilizers, resulting in water degradation, increased energy use, and common pollution. Of particular concern is the increased interest to reduce the environmental impacts of high quantities of water dedicated to irrigation by agricultural activities We are now truly recognizing the importance of sustainable measures in agriculture such as conservation of the vegetation cover and management approach to understand surface and deep soil responses to global change. The agroecology management based on key processes from natural ecosystems can help to solve some agricultural difficulties. Increasing studies on the Arbuscular mycorrhizal fungi (AMF) has showed their importance for soil ecology and studies on their biodiversity have spread in some agro-ecosystems such as corn and soybean monocultures. Therefore, it is needed to deeply study the mycorrhizal functions under global change. In this chapter, we examine the major developments and advances on mycorrhizal fungi based on recent research from South American countries. New reports on the occurrence of mycorrhizas in Amazonian dark earth, as well as the inoculum production of arbuscular mycorrhizal fungi native of soils under native forest covers, have resulted in a more detailed understanding of the soil biology from South America. Reports from Amazonian dark earth or “Terra preta do índio” soil has stimulated the use of biochar worldwide as a soil conditioner that can add value to non-harvested agricultural products and promote plant growth. Few reports from Brazil showed that the addition of inorganic fertilizer, compost and chicken manure resulted in increases in plant cover and plant species richness. In this sense, the biochar/mycorrhizae interactions also can be prioritized for sequestration of carbon in soils to contribute to climate change mitigation

    Ocorrência dos indicadores de risco para a deficiência auditiva infantil no decorrer de quatro anos em um programa de triagem auditiva neonatal de um hospital público Occurence of risk indicators for hearing loss over four years in a neonatal hearing screening program of a public hospital

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    OBJETIVO: Comparar a ocorrência dos indicadores de risco para a deficiência auditiva infantil ao longo de quatro anos, em um Programa de Triagem Auditiva Neonatal. MÉTODOS: Foram pesquisados os prontuários de 382 recém nascidos prematuros nascidos no Hospital São Paulo, de 2000 a 2004. RESULTADOS: Em 2000, encontramos 5,9% de casos de antecedentes familiares/consangüinidade, a qual aumentou de forma estatisticamente significante para 13,6% em 2003. A ventilação mecânica aumentou de forma estatisticamente significante de 24,6% casos em 2000, para 40,2% em 2004. O número de convulsões em RN foi de 4,2% em 2000 para 9,8% em 2004, aumento estatisticamente significante. Encontramos 11,0% de casos de infecção congênita em 2000, o que caiu para 4,3% em 2003. No ano de 2002, houve apenas um caso de sífilis, sendo que a ocorrência destas doenças diminuiu nos últimos anos. O HPIV foi de 15,3% no ano 2000 para 5% em 2003, com redução estatisticamente significante. Os casos de malformação caíram de 3,4% no ano 2000 para 0,7% em 2003. Os casos de ototoxicidade diminuíram de forma estatisticamente significante de 43,2% em 2000 para 30,0% em 2003. CONCLUSÃO: A análise estatística revelou aumento significante da ocorrência dos antecedentes familiares para a deficiência auditiva, do uso de ventilação mecânica e das convulsões neonatais. Os casos de infecção congênita e hemorragia periintraventricular diminuíram estatisticamente do ano 2000 para 2004. Os casos de malformação, baixo peso e ototoxicidade variaram de forma aleatória entre os anos estudados. E alguns indicadores de risco se mantiveram sem alterações estatisticamente significantes.<br>PURPOSE: To compare the occurrence of risk indicators for hearing loss in children over a period of four years, in a Neonatal Hearing Screening Program. METHODS: Three hundred and eighty-two files of preterm infants born at Hospital São Paulo in the period from 2000 to 2004 were researched. RESULTS: In 2000, 5.9% of the cases showed familiar antecedents and/or consanguinities, while in 2003 this indicator was present in 13.6% of the population. Mechanical ventilation showed significant increase from 24.6% in 2000 to 40.2% of the cases in 2004. The cases of neonatal seizures increased significantly from 4.2% in 2000 to 9.8% in 2004. Congenital infections showed significant decrease from 11.0% in 2000 to 4.3% in 2003. In 2002, only one case of syphilis was observed, demonstrating decrease in the occurrence of such diseases. The occurrence of peri-intraventricular hemorrhage significantly decreased from 15.3% in 2000 to 5% in 2003. Malformation cases decreased from 3.4% in 2000 to 0.7% in 2003. Ototoxicity cases showed significant decrease from 43.2% in 2000 to 30.0% in 2003. CONCLUSION: Statistical analysis revealed significant increase of familiar antecedents for hearing loss, use of mechanical ventilation and neonatal seizures during the period considered. Registers of congenital infections and peri-intraventricular hemorrhage showed significant decrease during the same period. Malformation, low birth weight and ototoxicity cases varied randomly, and some risk indicators didn't present any statistically significant variations

    Comparative morphology of the odoriferous system in three predatory stink bugs (Heteroptera: Asopinae)

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    The metathoracic scent system in Heteroptera produces and releases defensive volatile compounds. The odor produced by predatory stink bugs differs from phytophagous bugs, suggesting a variation between the structure and function of the metathoracic scent system. The anatomy and ultrastructure of the external thoracic efferent system, scent gland, and reservoir in the stink bug predators Brontocoris tabidus, Podisus nigrispinus, and Supputius cincticeps (Heteroptera: Pentatomidae: Asopinae) were studied. External thoracic efferent systems of B. tabidus, P. nigrispinus, and S. cincticeps have anatomical differences in ostiole, peritreme, and evaporatorium. Scent glands have a secretory portion and a reservoir. The reservoir has irregular projections, and in B. tabidus, it is enlarged and heart shaped, whereas in P. nigrispinus and S. cincticeps it is flattened and semicircular. The secretory tissue of the scent gland has well-developed globular secretory cells that produce odorous compounds, and the reservoir has a single layer of cubical cells lined by a cuticular intima. Secretory cells are type III with an intracellular end apparatus, well-developed nucleus with decondensed chromatin, and cytoplasm rich in mitochondria, lysosomes, granules, and smooth endoplasmic reticulum. These findings suggest that there are differences in physiological function of the odoriferous system and the volatile compounds produced by the secretory cells, which may indicate variation in defensive behavior of these species
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