315 research outputs found
Accelerated expansion from a non-minimal gravitational coupling to matter
It is shown that a non-minimal coupling between the scalar curvature and the
matter Lagrangian density may account for the accelerated expansion of the
Universe and provide, through mimicking, for a viable unification of dark
energy and dark matter. An analytical exploration is first performed, and a
numerical study is then used to validate the obtained results. The encountered
scenario allows for a better grasp of the proposed mechanism, and sets up the
discussion for improvements that can lead to a complete agreement with the
observational data.Comment: Latex file, 10 pages, 6 figure
Effectiviteit van herstelbeheer in vennen en duinplassen op de middellange termijn
Al sinds het opstarten van de regeling OBN zijn er herstelmaatregelen uitgevoerd in vennen en duinplassen. In een deel van de wateren bleek de waterkwaliteit en de vegetatie zich goed te herstellen in de eerste vijf jaren na de ingreep, maar de Fauna bleek op korte termijn overwegend negatief te reageren. Op deze korte termijn bleek vooral herstel van abiotiek en vegetatie op te treden indien zowel vermesting als eventuele verzuring werden bestreden en hernieuwde vermesting en verzuring werden voorkomen. In de praktijk betekende dit het verwijderen van sliblagen, plaggen van oevers, verwijderen van boomopslag en voorkomen van hernieuwde vermesting door o.a. bladinwaai en te grote aantallen watervogels. Verzuring kon het beste worden voorkomen door gedoseerde inlaat van voedselarm, gebufferd water of door bekalking van het inzijggebied. Na verloop van tijd bleken er nog de nodige onbeantwoorde vragen te zijn: Hoe pakken de herstelmaatregelen op de middellange termijn uit voor de levensgemeenschappen van vennen en duinplassen? Hoe reageert de fauna op de herstelmaatregelen? Hoe reageren sier- en kiezelwieren op de herstelmaatregelen? Moet het beheer worden aangepast nu de atmosferische depositie is afgenome
Is serum phosphorus control related to parathyroid hormone control in dialysis patients with secondary hyperparathyroidism?
Background
Elevated serum phosphorus (P) levels have been linked to increased morbidity and mortality in dialysis patients with secondary hyperparathyroidism (SHPT) but may be difficult to control if parathyroid hormone (PTH) is persistently elevated. We conducted a post hoc analysis of data from an earlier interventional study (OPTIMA) to explore the relationship between PTH control and serum P.
Methods
The OPTIMA study randomized dialysis patients with intact PTH (iPTH) 300–799 pg/mL to receive conventional care alone (vitamin D and/or phosphate binders [PB]; n = 184) or a cinacalcet-based regimen (n = 368). For patients randomized to conventional care, investigators were allowed flexibility in using a non-cinacalcet regimen (with no specific criteria for vitamin D analogue dosage) to attain KDOQI™ targets for iPTH, P, Ca and Ca x P. For those assigned to the cinacalcet-based regimen, dosages of cinacalcet, vitamin D sterols, and PB were optimized over the first 16 weeks of the study, using a predefined treatment algorithm. The present analysis examined achievement of serum P targets (≤4.5 and ≤5.5 mg/dL) in relation to achievement of iPTH ≤300 pg/mL during the efficacy assessment phase (EAP; weeks 17–23).
Results
Patients who achieved iPTH ≤ 300 pg/mL (or a reduction of ≥30% from baseline) were more likely to achieve serum P targets than those who did not, regardless of treatment group. Of those who did achieve iPTH ≤ 300 pg/mL, 43% achieved P ≤4.5 mg/dL and 70% achieved P ≤5.5 mg/dL, versus 21% and 46% of those who did not achieve iPTH ≤ 300 pg/mL. Doses of PB tended to be higher in patients not achieving serum P targets. Patients receiving cinacalcet were more likely to achieve iPTH ≤300 pg/mL than those receiving conventional care (73% vs 23% of patients). Logistic regression analysis identified lower baseline P, no PB use at baseline and cinacalcet treatment to be predictors of achieving P ≤4.5 mg/dL during EAP in patients above this threshold at baseline.
Conclusions
This post hoc analysis found that control of serum P in dialysis patients was better when serum PTH levels were lowered effectively, regardless of treatment received
Matemática, Literatura & Aulas
A aprendizagem da Matemática não ocorre por mera transmissão de saberes do professor para os alunos. A ideia de que o conhecimento pode passar linearmente de uma cabeça – daquele que sabe – para outra(s) cabeça(s) – para aqueles que querem saber –, pelas palavras ditas e escritas, não tem qualquer correspondência com a realidade. A aprendizagem é um processo adaptativo, simultaneamente individual e coletivo, baseado na ação e na reflexão, no qual a comunicação tem um papel fundamental, na medida que permite estabelecer ligação entre as pessoas
Avaliação do efeito da adubação NPK no crescimento de gravioleira no município de São Francisco do Pará.
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Characterization of natural occurrence of Oenocarpus distichus in the state of Maranhão, Brazil.
In Maranhão States Amazon, bacaba stands out as an important resource to local populations. It is employed in human and animal feeding, building houses, traditional medicine and manufacturer goods. The economically viable part of this species is the processed pulp known as bacaba, sold in natura or frozen. Considering the great potential of sustainable economic exploitation of native fruit trees, such as the bacaba, occurrence areas of natural populations of O. distichus in three municipalities of the Gurupi micro region and two of the Chapada das Mangabeiras were mapped in order to subsidize future researches regarding conservation and use of the germplasm. Bacaba populations were mapped in cities of the two microregions: 1) Gurupi where soils, in general, are of low natural fertility with predominance of dystrophic plinthudults and red-yellow dystrophic and plinthic soils and; 2) Chapada das Mangabeiras, where yellow dystrophic hapludox soils are found; and in the escarpments the litholic dystrophic neosoils are common. In these micro regions, bacaba populations are reduced to individuals found in backyards
Efeito da adubação NPK durante a formação de mudas de cupuaçuzeiros (Theobroma grandiflorum, Schum).
Biolistic co-transformation of Metarhizium anisopliae var. acridum strain CG423 with green fluorescent protein and resistance to glufosinate ammonium.
Avaliação do efeito da adubação mineral em plantas de cupuaçuzeiro (Theobroma grandiflorum) na fase de produção.
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