Efeito da temperatura e do fotoperíodo na duração e na taxa de crescimento de grãos de soja.

bitstream/CNPT-2010/40308/1/p-bp35.pd

Taxonomic and functional responses of benthic macroinvertebrate communities to hydrological and water quality variations in a heavily regulated river

Aquatic macroinvertebrates are frequently used to evaluate river system conditions and restoration project performance. A better understanding of macroinvertebrate community responses to multiple stressors is a primary challenge for river science. In this paper, macroinvertebrate responses to hydrological and water quality variability were studied in the regulated Oglio River (northern Italy). We hypothesized that in regulated rivers the hydrological, rather than the physico-chemical conditions, would affect macroinvertebrate communities and biomonitoring tools (taxonomic metrics and functional indices). Repeated sampling (six times a year) was performed at four sites downstream of four dams in a 30 km river stretch during 2014 and 2015. Data were analysed using a linear mixed effect framework, to take into account random variation due to site and sampling date, and with multivariate analysis to track changes in community structure. A total of 69 families and 134,693 organisms were identified. The investigated metrics were mainly affected by the coefficient of variation of discharge, minimum discharge, ammonium, and temperature. The short-term dynamics of hydrological and physico-chemical variables were generally less important than the overall random effects as drivers of macroinvertebrate-based metrics. However, the relevance of a random effect (site, time, their interaction) differed depending on the biological metrics analysed. Understanding potential differences in response to short term and short stretch conditions would benefit biomonitoring and restoration procedures in both regulated and natural rivers

Carbon and nitrogen stocks and humic fractions in Brazilian organosols.

Despite limited geographic expression of Organosols in Brazil, their high carbon storage capacity and natural environmental vulnerability justifies further studies on C and N stocks in these soils and their relationship to the nature of organic matter. Evaluation of physical and chemical properties of organic soils and their ability to store C is important so as to develop sustainable management practices for their preservation. The objectives of the study were to measure the total organic carbon stock (OCst), total nitrogen stock (Nst), and humic fractions in Organosols from different environments and regions of Brazil, and to correlate the data with soil chemical (pH, P, K, Ca2+, Mg2+, Al3+, H+Al, CEC, V) and physical properties (soil bulk density, Bd; organic matter density, OMd; total pore space, TPS; minimum residue, MinR; and proportion of mineral matter, MM), and degree of organic matter decomposition (rubbed fiber content; pyrophosphate index, PyI; and von Post index). For that purpose, 18 Organosol profiles, in a total of 49 horizons, were sampled under different land usage and plant coverage conditions. The profiles were located in the following Brazilian states - Alagoas, Bahia, Distrito Federal, Espírito Santo, Mato Grosso do Sul, Minas Gerais, Paraná, Rio de Janeiro, Rio Grande do Sul, Santa Catarina, and São Paulo. The OCst and Nst varied significantly among horizons and profiles. The Organosols exhibited, on average, 203.59 Mg ha-1 OCst and 8.30 Mg ha-1 Nst, and the highest values were found in profiles with pasture usage. The content of the humic fraction (humin, HUM; fulvic acid, FAF; and humic acid, HAF) and C storage varied in the soil horizons and profiles according to the degree of decomposition and other factors of soil formation. The OCst, Nst, OMd and the C stocks in the humic fractions were positively correlated. The values of acidity were lower in the soils with higher contents of mineral material, and low pH values were related to a high C/N ratio. The OCst and Nst were correlated with different soil properties, the most important being the degree of soil organic matter decomposition, which was inversely correlated

Soil carbon fractions in rubber trees, pasture, and secondary forest areas.

This study quantify the total organic carbon content, light fraction organic matter (LFOM), and soil organic matter fractions (from chemical and physical fractionations) in four different cultivation areas: 1 and 2) rubber tree clonal plantations (FX 3864 and IAN 873); 3) a pasture; and 4) a secondary forest. The research was carried out using soil samples from clonal plantations of eight-year-old rubber trees, located in the coastal plain (Tabuleiros Costeiros) of the state of Rio de Janeiro. The difference in the management of the rubber tree clone area promoted improvements in the soil quality, as it increased the carbon contents of the granulometric fractions, LFOM, and humic substances from the IAN 873 clone area. Both rubber tree areas evaluated presented higher mineral-associated organic carbon levels and humic substances than did the pasture area, reinforcing the reforestation potential of areas with degraded pastures through hevea culture

Nintedanib targets KIT D816V neoplastic cells derived from induced pluripotent stem cells of systemic mastocytosis

The KIT D816V mutation is found in >80% of patients with systemic mastocytosis (SM) and is key to neoplastic mast cell (MC) expansion and accumulation in affected organs. Therefore, KIT D816V represents a prime therapeutic target for SM. Here, we generated a panel of patient-specific KIT D816V induced pluripotent stem cells (iPSCs) from patients with aggressive SM and mast cell leukemia to develop a patient-specific SM disease model for mechanistic and drug-discovery studies. KIT D816V iPSCs differentiated into neoplastic hematopoietic progenitor cells and MCs with patient-specific phenotypic features, thereby reflecting the heterogeneity of the disease. CRISPR/Cas9n-engineered KIT D816V human embryonic stem cells (ESCs), when differentiated into hematopoietic cells, recapitulated the phenotype observed for KIT D816V iPSC hematopoiesis. KIT D816V causes constitutive activation of the KIT tyrosine kinase receptor, and we exploited our iPSCs and ESCs to investigate new tyrosine kinase inhibitors targeting KIT D816V. Our study identified nintedanib, a US Food and Drug Administration-approved angiokinase inhibitor that targets vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and fibroblast growth factor receptor, as a novel KIT D816V inhibitor. Nintedanib selectively reduced the viability of iPSC-derived KIT D816V hematopoietic progenitor cells and MCs in the nanomolar range. Nintedanib was also active on primary samples of KIT D816V SM patients. Molecular docking studies show that nintedanib binds to the adenosine triphosphate binding pocket of inactive KIT D816V. Our results suggest nintedanib as a new drug candidate for KIT D816V-targeted therapy of advanced SM.Peer reviewe