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1.
Raimundo Wagner Souza Aguiar Suetonio Fernandes dos Santos Fabricio da Silva Morgado Sergio Donizeti Ascencio Magnólia de Mendon?a Lopes Kelvinson Fernandes Viana Julcemar Didonet Bergmann Morais Ribeiro 《PloS one》2015,10(2)
This study investigated the toxic effects of essential oils isolated from Siparuna guianensis against Aedes aegypti, Culex quinquefasciatus (eggs, larvae, pupae, and adult) and Aedes albopictus (C6/36) cells. The oviposition-deterring activity, egg viability, and repellence activity in the presence of different essential oils concentrations were determined. The essential oils showed high toxicity to all developmental stages of A. aegypti and C. quinquefasciatus. Furthermore, the oils also showed high repellent activity towards the adult stage of mosquitoes (0.025 to 0.550 μg/cm2 skin conferred 100% repellence up to 120 min) and in contact with cultured insect cells (C6/36) induced death possibly by necrosis. The results presented in this work show the potential of S. guianensis essential oils for the development of an alternative and effective method for the natural control of mosquitoes in homes and urban areas. 相似文献
2.
J. R. Poortmans E. Blommaert M. Baptista M. E. De Broe E. J. Nouwen 《European journal of applied physiology and occupational physiology》1997,76(1):88-91
Post-exercise proteinuria is a common phenomenon in healthy subjects. Previous studies have used albumin (Alb) and β2-microglobulin (β2-m) molecules as representatives of high- and low-molecular-weight proteins. Recently, more specific markers of the human
kidney proximal tubule have been used to identify the precise site of alterations. Active male subjects underwent two strenuous
runs, one 400-m run and one 3000-m run. Urine was collected from the subjects before and after each event. Total protein (TP),
Alb, α1-microglobulin (α1-m), β2-m, intestinal alkaline phosphatase (IAP), tissue-nonspecific alkaline phosphatase (TNAP) and N-acetyl-β-d-glucosaminidase (NAG) were determined for each sample. The short-distance run (400 m) resulted in the largest increases (P ≤ 0.05) in TP (31-fold), Alb (100-fold) and β2-m (164-fold) as compared to the long-distance run (3000-m). The α1-m excretion rates were increased to a lesser extent by the exercises. The IAP activity was slightly increased (+90%) by the
400-m run while the TNAP and NAG activities showed a 6.8-fold and a 3.6-fold increase, respectively, after this event. Smaller
increases were recorded for the long-distance run (P = 0.05). To conclude, the present investigation showed that: (1) post-exercise proteinuria is related to the absolute intensity
of exercise; (2) the impairment of protein reabsorption is revealed better by changes in Alb and β2-m; (3) changes in TNAP and NAG activities could reveal biochemical modifications that occur in the proximal tubule, particularly
at the S1-S2 segment.
Accepted: 31 January 1997 相似文献
3.
Nadine Correia Santos Patrício Soares Costa Liliana Amorim Pedro Silva Moreira Pedro Cunha Jorge Cotter Nuno Sousa 《PloS one》2015,10(4)
Here we focus on factor analysis from a best practices point of view, by investigating the factor structure of neuropsychological tests and using the results obtained to illustrate on choosing a reasonable solution. The sample (n=1051 individuals) was randomly divided into two groups: one for exploratory factor analysis (EFA) and principal component analysis (PCA), to investigate the number of factors underlying the neurocognitive variables; the second to test the “best fit” model via confirmatory factor analysis (CFA). For the exploratory step, three extraction (maximum likelihood, principal axis factoring and principal components) and two rotation (orthogonal and oblique) methods were used. The analysis methodology allowed exploring how different cognitive/psychological tests correlated/discriminated between dimensions, indicating that to capture latent structures in similar sample sizes and measures, with approximately normal data distribution, reflective models with oblimin rotation might prove the most adequate. 相似文献
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Aino Juslén Juha Pykälä Saija Kuusela Lauri Kaila Jaakko Kullberg Jaakko Mattila Jyrki Muona Sanna Saari Pedro Cardoso 《Biodiversity and Conservation》2016,25(3):569-585
For the first time ever, the International Union for Conservation of Nature Red List Index for habitat types was calculated for an entire country, Finland. The RLIs were based on species threat assessments from 2000 and 2010 and included habitat definitions for all 10,131 species of 12 organism groups. The RLIs were bootstrapped to track statistically significant changes. The RLI changes of species grouped by habitats were negative for all habitat types except for forests and rural biotopes which showed a stable trend. Trends of beetles and true bugs were positive in rural and forest habitats. Other 16 observed trends of species group and habitat combinations were negative. Several trends observed were in accordance with studies focusing on particular taxa and habitats, and drivers for their change. This study demonstrates the usefulness of the RLI as a tool for observing habitat change based on species threat assessment data. 相似文献
8.
Murilo S. Baptista Rero M. Rubinger Emilson R. Viana José C. Sartorelli Ulrich Parlitz Celso Grebogi 《PloS one》2012,7(10)
The amount of information exchanged per unit of time between two nodes in a dynamical network or between two data sets is a powerful concept for analysing complex systems. This quantity, known as the mutual information rate (MIR), is calculated from the mutual information, which is rigorously defined only for random systems. Moreover, the definition of mutual information is based on probabilities of significant events. This work offers a simple alternative way to calculate the MIR in dynamical (deterministic) networks or between two time series (not fully deterministic), and to calculate its upper and lower bounds without having to calculate probabilities, but rather in terms of well known and well defined quantities in dynamical systems. As possible applications of our bounds, we study the relationship between synchronisation and the exchange of information in a system of two coupled maps and in experimental networks of coupled oscillators. 相似文献
9.
A multimetric index based on benthic macroinvertebrates for evaluation of Atlantic Forest streams at Rio de Janeiro State, Brazil 总被引:3,自引:0,他引:3
Darcilio F. Baptista Daniel F. Buss Mariana Egler Alexandre Giovanelli Mariana P. Silveira Jorge L. Nessimian 《Hydrobiologia》2007,575(1):83-94
This study describes the application of a protocol for biological assessment of water quality at first to third order streams
at Serra dos órg?os, an area covered by Atlantic Forest in Rio de Janeiro State, Brazil. Major impacts in the region are domestic
effluents and deforestation. Our main objective is to establish biocriteria for the establishment of the Serra dos órg?os
Multimetric Index (SOMI) based on benthic macroinvertebrates. We used data from previous studies, sampled by experienced biologists,
from 1999 through 2002. The benthic macroinvertebrate community was sampled in 12 reference sites and seven impaired sites
in three river basins: Guapimirim, Macaé and Grande, all from the same bioregion. From the 22 tested metrics, 6 were included
in the SOMI (% Diptera, % Coleoptera, Family Taxa, EPT Taxa, BMWP-CETEC and % Shredders). Scores (5, 3 or 1) were developed
for these metrics to allow for aggregation into the index. Seven intermediately impaired sites were used for evaluating the
applicability of the multimetric index. We concluded that the SOMI is a robust easy-to-apply tool for biomonitoring programs
in the Serra dos órg?os region, south-east Brazil.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorised users.
Handling editor: D. Dudgeon 相似文献
10.
We demonstrate that an external constant electric field is able to modify the secondary structure of a protein and induce a transition from a β-sheet into a helix-like conformation. This dramatic change is driven by a global rearrangement of the dipole moments at the amide planes. We also predict electric-field-induced modifications of the intermediate states of the protein. 相似文献