3,673 research outputs found
Practical application of the sign test on data from trial and meta-analysis.
Many practical situations faced in agricultural research does not allow assuming the normality of the data to be analyzed. In some of these situations, the researcher, not statistical, want to test hypotheses with minimal statistical security, but finds himself in trouble by not dominate approaches that require deeper knowledge in that discipline. The sign test has a very strong appeal for interpretability of results and is often sufficient for decision-making on the further direction of research or analysis. In this paper, we present two examples of application and interpretation of the test in the form available at Univariate routine SAS, one for data obtained for phosphorus content of the meta-analysis of available soil in areas under different forms of management, from dozens of published articles. The second example is data from testing in an area with strong physical condition of location of treatment and repetitions because the plants are perennials (coffee) and the treatments comprise the application of CO2 through a fixed system, expensive and rare (FACE - Free Air CO2 Enrichment). The results allowed us to evaluate the relevance of the hypotheses tested in a satisfactory manner considered by the researchers responsible for data
Relation between TNF-alpha and exercise induced bronchoconstriction
Introduction: Exercise-induced bronchoconstriction (EIB) describes an acute airway narrowing that occurs as a result of exercise. EIB is associated with a hyperosmolar environment that lead to airway smooth muscle contraction. The proinflammatory cytokine, TNF-alpha, has a prominent role in the development of airway hiperresponsiveness (AHR). A single bout of heavy exercise can trigger EIB. The aim of this research was to compare the response of TNF-alpha over time with the presence or absence of EIB in marathon runners. Methods: Thirty-eight male runners, who did not have any chronic or acute airway disease, performed maximal cardiopulmonary exercise testing on a treadmill coupled to the gas analyzer (FitMate ™, Cosmed, Italy). Was used a ramp protocol with fixed slope of 1% and an increase of load (1km/h) every minute. Spirometry was performed before (pre), immediately after, five, ten, fifteen and twenty minutes after exercise stress testing. Were considered positive for BIE those athletes that presented a decrease in expiratory volume in one second greater than 10% in any of the spirometric tests. Blood samples were obtained the day before the marathon, immediately and after 72 hours after the race. Cytokines were determined in serum by ELISA. Was used analysis of variance (ANOVA) with two factors, group and time of blood collection, considering repeated measures on the time factor. In the case of statistical significance for interaction group and blood was concluded that the behavior over time was significantly different between EIB negative (-) and EIB positive (+), in this case applied the method of Tukey\u27s multiple comparisons to determine the moment that occurred these differences (p\u3c0.05). Results: We observed a statistically significant difference (p=0.048) in the behavior of the concentration of TNF-alpha between groups EIB- and EIB+. The measure pre of the EIB+ have an higher concentration of TNF-alpha compared to those obtained immediately after the marathon for EIB+ and the results obtained at the three moments for EIB-. (Figure 1). Conclusion: Our results suggests that an inflammatory status in serum of the marathon runners presenting BIE, before the race may be associated with bronchoconstriction triggering
Theranostic applications of phage display to control leishmaniasis: Selection of biomarkers for serodiagnostics, vaccination, and immunotherapy
© 2015, Sociedade Brasileira de Medicina Tropical. All rights reserved. Phage display is a high-throughput subtractive proteomic technology used for the generation and screening of large peptide and antibody libraries. It is based on the selection of phage-fused surface-exposed peptides that recognize specific ligands and demonstrate desired functionality for diagnostic and therapeutic purposes. Phage display has provided unmatched tools for controlling viral, bacterial, fungal, and parasitic infections, and allowed identification of new therapeutic targets to treat cancer, metabolic diseases, and other chronic conditions. This review presents recent advancements in serodiagnostics and prevention of leishmaniasis -an important tropical parasitic disease- achieved using phage display for the identification of novel antigens with improved sensitivity and specificity. Our focus is on theranostics of visceral leishmaniasis with the aim to develop biomarker candidates exhibiting both diagnostic and therapeutic potential to fight this important, yet neglected, tropical disease.Peer Reviewe
The Motions of Clusters of Galaxies and the Dipoles of the Peculiar Velocity Field
In preceding papers of this series, TF relations for galaxies in 24 clusters
with radial velocities between 1000 and 9200 km/s (SCI sample) were obtained, a
Tully-Fisher (TF) template relation was constructed and mean offsets of each
cluster with respect to the template obtained. Here, an estimate of the
line-of-sight peculiar velocities of the clusters and their associated errors
are given. It is found that cluster peculiar velocities in the Cosmic Microwave
Background reference frame do not exceed 600 k/ms and that their distribution
has a line-of-sight dispersion of 300 k/ms, suggesting a more quiescent cluster
peculiar velocity field than previously reported. When measured in a reference
frame in which the Local Group is at rest, the set of clusters at cz > 3000
km/s exhibits a dipole moment in agreement with that of the CMB, both in
amplitude and apex direction. It is estimated that the bulk flow of a sphere of
6000 km/s radius in the CMB reference frame is between 140 and 320 km/s. These
results are in agreement with those obtained from an independent sample of
field galaxies (Giovanelli et al. 1998; see astro-ph/9807274)Comment: 9 pages, 2 tables, 7 figures, uses AAS LaTex; to appear in A
Nova Espécie de Ghinallelia Wygodzinsky, 1966 do Estado do EspÃrito Santo, Brasil (Hemiptera, Heteroptera, Reduviidae, Emesinae)
Ghinallelia talitae sp.nov. is described from EspÃrito Santo State, Brazil.Ghinallelia talitae sp.nov., proveniente do Estado do EspÃrito Santo, Brasil, é descrita
Development and validation of a simple and rapid capillary zone electrophoresis method for determination of nnrti nevirapine in pharmaceutical formulations
A simple and fast capillary zone electrophoresis (CZE) method has been developed and validated for quantification of a non-nucleoside reverse transcriptase inhibitor (NNRTI) nevirapine, in pharmaceuticals. The analysis was optimized using 10 mmol L-1 sodium phosphate buffer pH 2.5, +25 kV applied voltage, hydrodynamic injection 0.5 psi for 5 s and direct UV detection at 200 µm. Diazepam (50.0 µg mL-1) was used as internal standard. Under these conditions, nevirapine was analyzed in approximately less than 2.5 min. The analytical curve presented a coefficient of correlation of 0.9994. Limits of detection and quantification were 1.4 µg mL-1 and 4.3 µg mL-1, respectively. Intra- and inter-day precision expressed as relative standard deviations were 1.4% and 1.3%, respectively and the mean recovery was 100.81%. The active pharmaceutical ingredient was subjected to hydrolysis (acid, basic and neutral) and oxidative stress conditions. No interference of degradation products and tablet excipients were observed. This method showed to be rapid, simple, precise, accurate and economical for determination of nevirapine in pharmaceuticals and it is suitable for routine quality control analysis since CE offers benefits in terms of quicker method development and significantly reduced operating costs.Um método simples e rápido por eletroforese capilar foi desenvolvido e validado para a quantificação do inibidor não nucleosÃdeo da transcritase reversa (NNRTI) nevirapina, em medicamentos. A análise foi otimizada utilizando tampão fosfato de sódio 10 mmol L-1, pH 2,5, voltagem aplicada de +25 kV, injeção hidrodinâmica a 0,5 psi por 5 s e detecção UV em 200 µm. Diazepam (50,0 µg mL-1) foi usado como padrão interno. Sob estas condições, nevirapina foi analisada em aproximadamente menos de 2,5 min. A curva analÃtica apresentou um coeficiente de correlação de 0,9994. Os limites de detecção e quantificação foram 1,4 µg mL-1 e 4,3 µg mL-1, respectivamente. Precisões intra e inter-dia expressas como desvio padrão relativo foram 1,4% e 1,3%, respectivamente e a recuperação média foi de 100,81%. O fármaco foi submetido a testes de hidrólises (ácida, básica e neutra) e a estresse oxidativo. Não foi observada interferência por parte dos produtos de degradação, nem dos excipients na análise da nevirapina. Este método mostrou ser rápido, simples, preciso, exato e econômico para a determinação de nevirapina em produtos farmacêuticos e é apropriado para o controle de qualidade em análise de rotina uma vez que a eletroforese capilar oferece benefÃcios em termos de desenvolvimento rápido dos métodos e custos muito reduzidos de operação.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
The Tully-Fisher Relation and H_not
The use of the Tully-Fisher (TF) relation for the determination of the Hubble
Constant relies on the availability of an adequate template TF relation and of
reliable primary distances. Here we use a TF template relation with the best
available kinematical zero-point, obtained from a sample of 24 clusters of
galaxies extending to cz ~ 9,000 km/s, and the most recent set of Cepheid
distances for galaxies fit for TF use. The combination of these two ingredients
yields H_not = 69+/-5 km/(s Mpc). The approach is significantly more accurate
than the more common application with single cluster (e.g. Virgo, Coma)
samples.Comment: 10 pages, including 2 figures and 1 table; uses AAS LaTex. Submitted
to ApJ Letter
Cluster vs. Field Elliptical Galaxies and Clues on their Formation
Using new observations for a sample of 931 early-type galaxies we investigate
whether the \mg2--\so relation shows any dependence on the local environment.
The galaxies have been assigned to three different environments depending on
the local overdensity: clusters, groups, and field, having used our
completeredshift database to guide the assignment of galaxies. It is found that
cluster, group and field early-type galaxies follow almost identical \mg2--\so\
relations, with the largest \mg2 zero-point difference (clusters minus field)
being only mag. No correlation of the residuals is found with
the morphological type or the bulge to disk ratio. Using stellar population
models in a differential fashion, this small zero-point difference implies a
luminosity-weighted age difference of only Gyr between the
corresponding stellar populations, with field galaxies being younger. The
mass-weighted age difference could be significantly smaller, if minor events of
late star formation took place preferentially in field galaxies. We combine
these results with the existing evidence for the bulk of stars in cluster
early-type galaxies having formed at very high redshift, and conclude that the
bulk of stars in galactic spheroids had to form at high redshifts (z\gsim 3),
no matter whether such spheroids now reside in low or high density regions. The
cosmological implications of these findings are briefly discussed.Comment: 16 pages, 2 figures, accepted for publication in the ApJ.
The first 62 AGN observed with SDSS-IV MaNGA -- III: stellar and gas kinematics
We investigate the effects of Active Galactic Nuclei (AGN) on the gas
kinematics of their host galaxies, using MaNGA data for a sample of 62 AGN
hosts and 109 control galaxies (inactive galaxies). We compare orientation of
the line of nodes (kinematic Position Angle - PA) measured from the gas and
stellar velocity fields for the two samples. We found that AGN hosts and
control galaxies display similar kinematic PA offsets between gas and stars.
However, we note that AGN have larger fractional velocity dispersion
differences between gas and stars [] when compared to their controls, as
obtained from the velocity dispersion values of the central (nuclear) pixel
(2.5" diameter). The AGN have a median value of of
, while the the median value for the control
galaxies is . 75% of the AGN show
, while 75% of the normal galaxies show , thus we suggest that the parameter can be
used as an indicative of AGN activity. We find a correlation between the
[OIII]5007 luminosity and for our sample. Our main
conclusion is that the AGN already observed with MaNGA are not powerful enough
to produce important outflows at galactic scales, but at 1-2 kpc scales, AGN
feedback signatures are always present on their host galaxies.Comment: 19 pages, 8 figures, published in MNRA
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