7,796 research outputs found
Validation of a food frequency questionnaire for children and adolescents aged 4 to 11 years living in Salvador, Bahia.
OBJECTIVE: To assess the validity of a food frequency questionnaire (FFQ) by applying it to children and adolescents living in Salvador, Bahia. METHODS: The validity of this FFQ with 98 food items was investigated among 108 children and adolescents who were selected from a sample of 1445 that had been planned for a study on the risk factors for asthma and other allergic diseases. The adults responsible for these children and adolescents gave responses for a 24-hour recall (R24h) and an FFQ. The average energy and nutrient values from the FFQ were compared with those from the R24h by means of the paired t test and Pearson correlation coefficients. The concordance was evaluated using the Bland-Altman method and kappa statistics. RESULTS: The energy and nutrient intake estimated using the FFQ was significantly higher than what was obtained using the R24h. The correlation coefficients adjusted for energy were statistically significant for protein, fat, vitamin C and zinc. The weighted kappa values ranged from 0.06 for vitamin A (p = 0.24) to 0.34 for energy (p < 0.00). The results from the Bland-Altman plots for lipid, protein and zinc showed the most significant validity parameters, and zinc was found to show the best concordance. CONCLUSION: The results suggest that the FFQ showed satisfactory validity for use in studies involving children and adolescents
On three-point correlation functions in the gauge/gravity duality
We study the effect of marginal and irrelevant deformations on the
renormalization of operators near a CFT fixed point. New divergences in a given
operator are determined by its OPE with the operator D that generates the
deformation. This provides a scheme to compute the couplings a_DAB between the
operator D and two arbitrary operators O_A and O_B. We exemplify for the case
of N=4 SYM, considering the simplest case of the exact Lagrangian deformation.
In this case the deformed anomalous dimension matrix is determined by the
derivative of the anomalous dimension matrix with respect to the coupling. We
use integrability techniques to compute the one-loop couplings a_LAB between
the Lagrangian and two distinct large operators built with Magnons, in the
SU(2) sector of the theory. Then we consider a_DAA at strong coupling, and show
how to compute it using the gauge/gravity duality, when D is a chiral operator
dual to any supergravity field and O_A is dual to a heavy string state. We
exemplify for the Lagrangian and operators O_A dual to heavy string states,
showing agreement with the prediction derived from the renormalization group
arguments
Polarised black holes in ABJM
We numerically construct asymptotically solutions to
Einstein-Maxwell-dilaton theory. These have a dipolar electrostatic potential
turned on at the conformal boundary . We find two
classes of geometries: soliton solutions that encode the full
backreaction of the electric field on the geometry without a horizon, and
neutral black holes that are "polarised" by the dipolar potential. For a
certain range of the electric field , we find two distinct
branches of the soliton that exist for the same value of .
For the black hole, we find either two or four branches depending on the value
of the electric field and horizon temperature. These branches meet at critical
values of the electric field and impose a maximum value of that
should be reflected in the dual field theory. For both the soliton and black
hole geometries, we study boundary data such as the stress tensor. For the
black hole, we also consider horizon observables such as the entropy. At finite
temperature, we consider the Gibbs free energy for both phases and determine
the phase transition between them. We find that the soliton dominates at
low temperature for an electric field up to the maximum value. Using the
gauge/gravity duality, we propose that these solutions are dual to deformed
ABJM theory and compute the corresponding weak coupling phase diagram
Diâmetro médio predominante de partÃculas do solo
Apresenta-se um modelo empÃrico capaz de representar, analiticamente, a curva de distribuição textural acumulada de partÃculas de um solo e, a partir desse modelo, obter uma expressão que fornece o diâmetro médio predominante de partÃculas (∅m), que representa o tamanho médio de partÃculas que ocorrem com maior freqüência no solo. Essas expressões podem ser aplicadas tanto na fÃsica do solo quanto em estudos geológicos, geomorfológicos e sedimentológicos
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Polarised black holes in AdS
© 2016 IOP Publishing Ltd. We consider solutions in Einstein-Maxwell theory with a negative cosmological constant that asymptote to global AdS 4 with conformal boundary . At the sphere at infinity we turn on a space-dependent electrostatic potential, which does not destroy the asymptotic AdS behaviour. For simplicity we focus on the case of a dipolar electrostatic potential. We find two new geometries: (i) an AdS soliton that includes the full backreaction of the electric field on the AdS geometry; (ii) a polarised neutral black hole that is deformed by the electric field, accumulating opposite charges in each hemisphere. For both geometries we study boundary data such as the charge density and the stress tensor. For the black hole we also study the horizon charge density and area, and further verify a Smarr formula. Then we consider this system at finite temperature and compute the Gibbs free energy for both AdS soliton and black hole phases. The corresponding phase diagram generalizes the Hawking-Page phase transition. The AdS soliton dominates the low temperature phase and the black hole the high temperature phase, with a critical temperature that decreases as the external electric field increases. Finally, we consider the simple case of a free charged scalar field on with conformal coupling. For a field in the SU(N ) adjoint representation we compare the phase diagram with the above gravitational system
Resistance of citrus genotypes to Phyllocnitis citrella Stainton (Lepidoptera: Gracillariidae)
The development and reproduction of the citrus leafminer (CLM), Phyllocnistis citrella Stainton, were evaluated in six citrus genotypes in order to identify genotypes with resistance traits that could be applied in a program for the development of citrus varieties resistant to the citrus leafminer. Tests were conducted under controlled laboratory conditions (25 ± 1ºC, 70 ± 10% RH, and 14h photophase). Seedlings of each genotype tested were infested with eggs obtained from a stock colony of CLM maintained on 'Cravo' lemon (Citrus limonia L. Osbeck), and the duration and survival of the eggs, larval and pupal stages, pupal size and weight, fecundity and longevity of adults, and sex ratio were evaluated. No influence was observed on the duration and survival of eggs, larvae and pupae of P. citrella. However, pupae obtained in the hybrid C x R4 were significantly smaller and lighter than pupae from the remaining treatments. Adult females from the hybrids C x R4 and C x R315 were the least fecund. However, the lowest value for the corrected reproductive potential (CRP) was recorded in the hybrid C x R315, suggesting that this genotype is the least favorable for the development and reproduction of CLM. On the other hand, the highest CRP value obtained in the 'Rugoso' lemon confirms the susceptibility of this genotype, indicating it as the most suitable for CLM.Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Metabolic turnover and dynamics of modified ribonucleosides by ¹³C labeling
Tandem mass spectrometry (MS/MS) is an accurate tool to assess modified ribonucleosides and their dynamics in mammalian cells. However, MS/MS quantification of lowly abundant modifications in non-ribosomal RNAs is unreliable, and the dynamic features of various modifications poorly understood. Here, we developed a 13C labeling approach, called 13C-dynamods, to quantify the turnover of base modifications in newly transcribed RNA. This turnover-based approach helped to resolve mRNA from ncRNA modifications in purified RNA or free ribonucleoside samples, and showed the distinct kinetics of the N6-methyladenosine (m6A) versus 7-methylguanosine (m7G) modification in polyA+-purified RNA. We uncovered that N6,N6-dimethyladenosine (m62A) exhibits distinct turnover in small RNAs and free ribonucleosides when compared to known m62A-modified large rRNAs. Finally, combined measurements of turnover and abundance of these modifications informed on the transcriptional versus posttranscriptional sensitivity of modified ncRNAs and mRNAs, respectively, to stress conditions. Thus, 13C-dynamods enables studies of the origin of modified RNAs at steady-state and subsequent dynamics under non-stationary conditions. These results open new directions to probe the presence and biological regulation of modifications in particular RNAs
Patterns of Parental Reactions to Their Children’s Negative Emotions: A Cluster Analysis with a Clinical Sample
Parents' emotion socialization practices are an important source of influence in the development of children's emotional competencies This study examined parental reactions to child negative emotions in a clinical sample using a cluster analysis approach and explored the associations between clusters of parents' reactions and children's and parents' adjustment. The sample comprised 80 parents of Portuguese children (aged 3-13 years) attending a child and adolescent psychiatry unit. Measures to assess parental reactions to children's negative emotions, parents' psychopathological symptoms, parents' emotion dysregulation, and children's adjustment were administered to parents. Model-based cluster analysis resulted in three clusters: low unsupportive, high supportive, and inconsistent reactions clusters. These clusters differed significantly in terms of parents' psychopathological symptoms, emotion dysregulation, and children's adjustment. A pattern characterized by high supportive reactions to the child's emotions was associated with higher levels of children's adjustment. On the other hand, an inconsistent reactions pattern was associated with the worst indicators of children's adjustment and parental emotion dysregulation. These results suggest the importance of supporting parents of children with emotional and behavioural problems so that they can be more responsive to their children's emotional manifestations.info:eu-repo/semantics/publishedVersio
Treadmill walking differently affects body composition and metabolic parameters of female rats from normal or small litters
This work assessed whether walking affects bodily development and metabolic parameters of female rats raised in small litters (three pups, group S) or control litters (nine pups, group C). After weaning, some of the rats had five sessions per week of a 30-min treadmill walking (CE and SE), while the others remained sedentary (CS and SS) until the age of 120 days. Exercise caused a reduction of body weight (CS/CE = 1.18), Lee index (CS/CE = 1.04), fasting blood glucose (CS/CE = 1.35), mesenteric (CS/CE = 1.23), and ovarian fat (CS/CE = 1.33) in CE, but only glucose was decreased in SE (SS/SE = 1.16). The diameter of adipocytes decreased to a half in the small-litter groups. Exercise increased subcutaneous (CS/CE = 0.88 and SS/SE = 0.71), but decreased retroperitoneal adipocytes (CS/CE = 1.2 and SS/SE = 1.3). Litter size reduction had little impact on females at the age of 120 days, but the light physical activity seemed insufficient to counteract all the effects of lactational overfeeding. On the other hand, pups from exercised mothers had a decrease in their biometric and glycemic indexes, demonstrating the transgenerational action of regular, although light, exercise
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