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Plants not only respond to herbivorous damage but adjust their defense system after egg deposition by pest insects. Thereby, parasitoids use oviposition-induced plant volatiles to locate their hosts. We investigated the olfactory behavioral responses of Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) to volatile blends emitted by maize (Zea mays L.) with singular and stacked events after oviposition by Spodoptera frugiperda Smith, 1797 (Hymenoptera: Trichogrammatidae) moths. Additionally, we examined possible variations in gene expression and on oviposition-induced volatiles. We used a Y-tube olfactometer to test for the wasp responses to volatiles released by maize plants oviposited by S. frugiperda and not-oviposited plants. Using the real-time PCR technique (qRT-PCR), we analyzed the expression of lipoxygenase and three terpene synthases genes, which are enzymes involved in the synthesis of volatile compounds that attract parasitoids of S. frugiperda. Olfactometer tests showed that T. pretiosum is strongly attracted by volatiles from transgenic maize emitted by S. frugiperda oviposition (VTPRO 3, more than 75% individuals were attracted). The relative expression of genes TPS10, LOX e STC was higher in transgenic hybrids than in the conventional (isogenic line) hybrids. The GC-MS analysis revealed that some volatile compounds are released exclusively by transgenic maize. This study provides evidence that transgenic hybrids enhanced chemical cues under oviposition-induction and helped to increase T. pretiosum efficiency in S. frugiperda control. This finding shows that among the evaluated hybrids, genetically modified hybrids can improve the biological control programs, since they potentialize the egg parasitoid foraging, integrating pest management.
We aimed at evaluating the association of maternal pre-pregnancy nutritional status with offspring anthropometry and body composition. We also evaluated whether these associations were modified by gender, diet and physical activity and mediated by birth weight.
Birth cohort study.
Waist circumference was measured with an inextensible tape, and fat and lean mass were measured using dual-energy X-ray absorptiometry. Multiple linear regression was used to adjust for possible confounders and allele score of BMI. We carried out mediation analysis using G-formula.
In 1982, 1993 and 2004, all maternity hospitals in Pelotas (South Brazil) were visited daily and all live births whose families lived in the urban area of the city were evaluated. These subjects have been followed up at different ages.
Offspring of obese mothers had on average higher BMI, waist circumference and fat mass index than those of normal weight mothers, and these differences were higher among daughters. The magnitudes of the association were similar in the cohorts, except for height, where the association pattern was not clear. In the 1982 cohort, further adjustment for a BMI allele score had no material influence on the magnitude of the associations. Mediation analyses showed that birth weight captured part of this association.
Our findings suggest that maternal pre-pregnancy nutritional status is positively associated with offspring BMI and adiposity in offspring. And this association is higher among daughters whose mother was overweight or obese and, birth weight explains part of this association.
Recruitment is related to the occupation of the substrate by fouling organisms. It plays an important role in the maintenance and distribution of benthic populations, being under the influence of biotic and abiotic factors. In the present work, the recruitment of calcareous sponges was monitored over two years in a marina at Todos os Santos Bay, a large bay in the tropical portion of the Brazilian coast. Artificial plates were immersed, being replaced bimonthly and the potential influence of the seawater temperature, photoperiod and precipitation on the number of sponge recruits was tested. The results showed that the number of calcareous sponge recruits had significant temporal variation. Nevertheless, different species showed different patterns over time. Significant differences were observed for Sycon avus, Sycon sp. and Leucandra serrata, and the periods with the highest number of recruits were different amongst them. Sycon bellum, Paraleucilla incomposita, Leucilla sp. and Heteropia glomerosa did not show significant variation in the number of recruits over time. None of the three tested environmental factors were correlated with the number of recruits, but results indicated S. avus recruitment might be driven by seawater temperature. Our results contribute to improve the current knowledge on the dynamics of each species found on the plates and reinforce the general view that the pattern of recruitment varies greatly in Calcarea, even amongst sympatric species.
Literature describes breast milk as the best food for the newborn, recommending exclusive breastfeeding for up to 6 months of age. However, it is not available for more than 40% of children worldwide. Pharmacological and non-pharmacological models of 3-day early weaning were developed in rodents to investigate later outcomes related solely to this nutritional insult. Thus, the present work aimed to describe biometric, nutritional, biochemical, and cardiovascular outcomes in adult male rats submitted to 3-day early weaning achieved by maternal deprivation. This experimental model comprises not only nutritional insult but also emotional stress, simulating mother abandoning. Male offspring were physically separated from their mothers at 21st (control) or 18th (early weaning) postnatal day, receiving water/food ad libitum. Analysis performed at postnatal days 30, 90, 150, and 365 encompassed body mass and food intake monitoring and serum biochemistry determination. Further assessments included hemodynamic, echocardiographic, and cardiorespiratory evaluation. Early-weaned males presented higher body weight when compared to control as well as dyslipidemia, higher blood pressure, diastolic dysfunction, and cardiac hypertrophy in adult life. Animals early deprived of their mothers have also presented a worse performance on the maximal effort ergometer test. This work shows that 3-day early maternal deprivation favors the development of cardiovascular disease in male rats.
This study is aimed to establish biological, psychological, and social risk factors for a group of patients hospitalized following a suicide attempt or suicide ideation, and controls. Patients were characterized by different degrees of severity, namely: 1)Nearly Lethal Suicide Attempt 2)Suicide Attempt with a Survival Strategy 3)Suicidal Ideation without Suicide Attempt, 4) Control inpatients without suicide ideation or history.
We evaluated nearly 100 patients using several scales for the assessment of: Personality, Reasons for Living, Axis I, Social factors and History of previous suicide attempts.
There is a higher proportion of young, adolescent, single and female patients. Most of them asked for help after the suicide attempt. The majority had a comorbid diagnosis for substance abuse. In reference to personality disorders, we found counterintuitively, that those who made a Nearly Lethal Suicide attempt were healthier than the subjects who's suicide attempt was less severe.
This finding is also reflected in the fact that those with a less severe suicide attempt rated much higher on impulsivity and also were much less satisfied with their family and friends. This last trait is probably associated with personality disorders.
Patients who made a Nearly lethal suicide attempt had much higher on the Reasons for Living questionnaire. Compared to less severe suicide attempters, they had more reasons to stay alive. This last finding might be an early aftereffect of the attempt.
In this work we explore the radiocarbon (14C) signal as an independent tool to assess the year of formation of individual tree rings of tropical species in northern Brazil. Three different species were analyzed in this work: Dipteryx magnifica, Enterolobium maximum, and Hymenolobium petraeum. The studied samples are from the stem of only one individual of each species, all cut down in 2008 in Porto Trombetas, Pará, Brazil. Individual tree rings were identified based on wood anatomy and they were counted from bark to pith. Several rings were selected for 14C analysis in order to cover the overall shape of the 14C atmospheric bomb peak (after 1955). The 14C content was measured at Laboratory of Radiocarbon, Universidade Federal Fluminense (LAC-UFF). Results are compared with the Southern Hemisphere 14C atmospheric calibration curves. For E. maximum and H. petraeum the 14C signal exhibits an overall good match with the SH zone 3 and suggests annual seasonality in the growth-ring formation. These species offer suitable characteristics for dendrochronology. The D. magnifica shows mismatches in the 14C measurements that are likely a result of difficulties in identifying ring boundaries with certainty. Additional techniques may be helpful to disentangle the origin of this discrepancy.
We performed two different approaches (broth enrichment step prior to culture (BEC) and PCR (BEPCR)) for detecting Streptococcus pneumoniae from nasopharyngeal specimens collected from 242 children aged <6 years attending one hospital (n = 140) and one childcare centre (n = 102) in a major urban area in Brazil. These specimens were collected immediately before the introduction of the 10-valent pneumococcal conjugate vaccine (PCV10) and the 13-valent vaccine (PCV13) for routine use in Brazil. Results were compared with previous findings obtained with direct culture (DC) on a selective medium. Colonisation prevalence was 58·3% (n = 141), being higher among children attending the childcare centre (62·7% vs. 55%). The culture-based methods (DC and BEC) enabled the detection of S. pneumoniae in 119 (49·2%) and 115 (47·5%) children, respectively. The PCR-based method (BEPCR) was more sensitive and 137 (56·6%) carriers were identified. Twenty-six serogroups/serotypes were identified, predominantly 6B, 19F, 14, 6A, 15C and 23F. Multiple colonisation was observed in 13 (5·4%) children. The estimated serotypes coverage of available PCVs was 40·4% for the 10-valent (included in the Brazilian immunisation programme) and 55·8% for the 13-valent (only available in private clinics). The use of robust approaches to obtain a more realistic insight about the asymptomatic carrier status is of paramount importance to estimate and assess the impact of vaccine implementation. The combination between culture-based and molecular methods constitutes a suitable strategy.
There are still uncertainties on the psychometric validity of the DSM-5 attention deficit hyperactivity disorder (ADHD) criteria for its use in the adult population. We aim to describe the adult ADHD phenotype, to test the psychometric properties of the DSM-5 ADHD criteria, and to calculate the resulting prevalence in a population-based sample in their thirties.
A cross-sectional evaluation using the DSM-5 ADHD criteria was carried out in 3574 individuals from the 1982 Pelotas Birth Cohort. Through receiver operator curve, latent and regression analyses, we obtained parameters on construct and discriminant validity. Still, prevalence rates were calculated for different sets of criteria.
The latent analysis suggested that the adult ADHD phenotype is constituted mainly by inattentive symptoms. Also, inattention symptoms were the symptoms most associated with impairment. The best cut-off for diagnosis was four symptoms, but sensitivity and specificity for this cut-off was low. ADHD prevalence rates were 2.1% for DSM-5 ADHD criteria and 5.8% for ADHD disregarding age-of-onset criterion.
The bi-dimensional ADHD structure proposed by the DSM demonstrated both construct and discriminant validity problems when used in the adult population, since inattention is a much more relevant feature in the adult phenotype. The use of the DSM-5 criteria results in a higher prevalence of ADHD when compared to those obtained by DSM-IV, and prevalence would increase almost threefold when considering current ADHD syndrome. These findings suggest a need for further refinement of the criteria for its use in the adult population.
This study aimed to assess the contribution of hosts characteristics (rodents and marsupials) in the organization of ectoparasite communities present in woodland patches in western central Brazil. We verified the effect of host species, sex, body mass and vertical strata in addition to the role of seasonality on the ectoparasite composition, richness and abundance. The total sampling effort was 22 032 trap-nights equally distributed in 54 woodland patches. Variance partition and principal coordinate analysis were used to verify the existence of significant relationships between response variables and predictors. As expected, host species was the most important variable in ectoparasite community assembly. The composition, richness and abundance of mites and lice were highly influenced by host species, although higher for mites than for lice. Host body mass had a determining role on the richness and abundance of tick species. Vertical stratification and seasonality had weak influence, while the sex of the host had no influence on the organization of these communities. The results are closely related to the evolutionary characteristics of the species involved, as well as with local environmental characteristics of the study area.
One of the most important parts of a hybrid reactor is the cladding because it should withstand high temperatures, neutrons with high energy, high neutron flux, as well as provide the first security contention. Besides, the material should have good mechanical properties to remove the heat. Although, the cladding material choice will have a great influence on criticality calculations. In previous works on ADS there is no cladding used, therefore in this paper it is tested different cladding materials based on SS-316, ODS, T91 and 15-15Ti used in nuclear reactors, to study the variations on the fuel depletion and variations on the neutronic parameters. The results using the cladding are compared with the one obtained without using it. The best material choice is based on the neutronic parameters that presents the closest behavior to the ADS simulated without clad.
Episodes of depression and anxiety (D&A) during the transition from late adolescence to adulthood, particularly when persistent, are predictive of long-term disorders and associated public health burden. Understanding risk factors at this time is important to guide intervention. The current objective was to investigate the associations between maternal symptoms of D&A with offspring symptoms during their transition to adulthood.
Data from a large population-based birth cohort study, in South Brazil, were used. Prospective associations between maternal D&A and offspring risk of these symptoms during the transition to adulthood (18/19, 24 and 30 years) were estimated.
Maternal D&A in adolescence was associated with offspring symptoms across the transition to adulthood, associations were consistently stronger for females than for males. Daughters whose mothers reported D&A were 4.6 times (95% confidence interval 2.71–7.84) as likely to report D&A at all three time-points, than daughters of symptom-free mothers.
Maternal D&A is associated with persistent D&A during the daughter's transition to adulthood. Intervention strategies should consider the mother's mental health.
In traditional transit timing variations (TTVs) analysis of multi-planetary systems, the individual TTVs are first derived from transit fitting and later modelled using n-body dynamic simulations to constrain planetary masses. We show that fitting simultaneously the transit light curves with the system dynamics (photo-dynamical model) increases the precision of the TTV measurements and helps constrain the system architecture. We exemplify the advantages of applying this photo-dynamical model to a multi-planetary system found in K2 data very close to 3:2 mean motion resonance, K2-19. In this case the period of the larger TTV variations (libration period) is much longer (>1.5 years) than the duration of the K2 observations (80 days). However, our method allows to detect the short period TTVs produced by the orbital conjunctions between the planets that in turn permits to uniquely characterise the system. Therefore, our method can be used to constrain the masses of near-resonant systems even when the full libration curve is not observed.
The aim of this study was to estimate the association between birth order and number of siblings with body composition in adolescents. Data are from a birth cohort study conducted in Pelotas, Brazil. At the age of 18 years, 4563 adolescents were located, of whom 4106 were interviewed (follow-up rate 81·3 %). Of these, 3974 had complete data and were thus included in our analysis. The variables used in the analysis were measured during the perinatal period, or at 11, 15 and/or 18 years of age. Body composition at 18 years was collected by air displacement plethysmography (BOD POD®). Crude and adjusted analyses of the association between birth order and number of siblings with body composition were performed using linear regression. All analyses were stratified by the adolescent sex. The means of BMI, fat mass index and fat-free mass index among adolescents were 23·4 (sd 4·5) kg/m2, 6·1 (sd 3·9) kg/m2 and 17·3 (sd 2·5) kg/m2, respectively. In adjusted models, the total siblings remained inversely associated with fat mass index (β = − 0·37 z-scores, 95 % CI − 0·52, − 0·23) and BMI in boys (β = − 0·39 z-scores, 95 % CI − 0·55, − 0·22). Fat-free mass index was related to the total siblings in girls (β = 0·06 z-scores, 95 % CI − 0·04, 0·17). This research has found that number of total siblings, and not birth order, is related to the fat mass index, fat-free mass index and BMI in adolescents. It suggests the need for early prevention of obesity or fat mass accumulation in only children.
The response of Grapholita molesta (Busck) males to three-component sex pheromone blends containing a 100% ratio of the major sex pheromone component, (Z)-8-dodecenyl acetate and a 10% ratio of (Z)-8-dodecenol, but with varying ratios of (E)-8-dodecenyl acetate (0.4, 5.4, 10.4, 30.4, and 100.1% E-blends) was tested with populations in eight stone and pome fruit orchards in Europe, Asia, and North and South America. Traps baited with the 5.4% E-blend caught significantly more males than traps with any other blend with all populations. Significantly more males were caught in traps baited with the 10.4% E-blend than in traps with the remaining blends, except with the 0.4% E-blend in Turkey. Significant differences in male moth catches occurred between the other blends with the 0.4>30.4% E-blend, and the 30.4>100.1% E-blend. Male moth catches with the 100.1% E-blend only differed from the hexane control in Chile. No apparent differences were noted to these blends in populations collected from pome or stone fruits. Flight tunnel assays to synthetic blends with a subset of populations were similar to the field results, but the breadth of the most attractive E-blends was wider. Flight tunnel assays also demonstrated a high level of male–female cross-attraction among field-collected populations. Female gland extracts from field-collected populations did not show any significant variation in their three-component blends. The only exceptions in these assays were that long-term laboratory populations were less responsive and attractive, and produced different blend ratios of the two minor components than recently collected field populations.
The majority of extra-solar planets have been discovered (or confirmed after follow-up) through radial-velocity (RV) surveys. Using ground-based spectrographs such as High Accuracy Radial Velocity Planetary Search (HARPS) and HARPS-North, it is now possible to detect planets that are only a few times the mass of the Earth. However, the presence of dark spots on the stellar surface produces RV signals that are very similar in amplitude to those caused by orbiting low-mass planets. Disentangling these signals has thus become the biggest challenge in the detection of Earth-mass planets using RV surveys. To do so, we use the star's lightcurve to model the RV variations produced by spots. Here we present this method and show the results of its application to CoRoT-7.
Since the discovery of the transiting Super-Earth CoRoT-7b, several investigations have been made of the number and precise masses of planets present in the system, but they all yield different results, owing to the star's high level of activity. Radial velocity (RV) variations induced by stellar activity therefore need to be modelled and removed to allow a reliable detection of all planets in the system. We re-observed CoRoT-7 in January 2012 with both HARPS and the CoRoT satellite, so that we now have the benefit of simultaneous RV and photometric data. We fitted the off-transit variations in the CoRoT lightcurve using a harmonic decomposition similar to that implemented in Queloz et al. (2009). This fit was then used to model the stellar RV contribution, according to the methods described by Aigrain et al. (2011). This model was incorporated into a Monte Carlo Markov Chain in order to make a precise determination of the orbits of CoRoT-7b and CoRoT-7c. We also assess the evidence for the presence of one or two additional planetary companions.
Spermatogenesis is a complex process of cell proliferation, meiosis and differentiation. In order to determine the genetic mechanisms that control this process we need to develop adequate methodologies for the purification of stage-specific germ cells. In this study we aim to evaluate four markers (c-kit, oct-4, Integrin α6 and Integrin β1), used to isolate spermatogonial stem cells in mammals, as possible markers to isolate/sort testicular adult stem and progenitor cells in humans.
We investigated the first cluster of pandemic influenza H1N1 2009 reported in Brazil in May 2009. The index case-patient had travelled from the USA and had contact with 11 relatives before she presented with symptoms. We conducted face-to-face or telephone interviews with the index case-patient and all suspect cases. We found evidence of pre-symptomatic transmission of the virus to four of her contacts. This finding has public health implications because it indicates that viral transmission in communities may not be prevented solely by isolating symptomatic case-patients.
The Wide Angle Search for Planet (WASP) project is one of the leading projects in the discovery of transiting exoplanets. We present 1) the current status of the WASP-North survey, 2) our recent exoplanet discoveries, and 3) we exemplify how these results fit into our understanding of transiting exoplanet properties and how they can help to understand exoplanet diversity.