950 resultados para Traits de modernité
Resumo:
Eucalyptus camaldulensis has great importance in Brazil because of their phenotypic plasticity for different environmental conditions, as soils, altitudes and rainfall. This study is an investigation of a base population of E. camaldulensis from Australia through a progeny test implanted in Selviria, MS. The trial was established in a randomized block design, with 25 families and 60 replications of single tree plots. Genetic parameters for anatomic traits and volume shrinkage were estimated, as well as their correlations with wood basic density. No significant differences among progenies were observed for the traits studied. The additive genetic variation coefficient at individual and among progeny levels ranged from low (0.26%) to high (16.98%). The narrow sense heritability at individual and family means levels also ranged from low (0.01) to high (0.87). This indicates that some traits are under strong genetic control and can be improved by selection. In the present situation, in order to attain the highest genetic gains, the sequential selection among and within progeny would be recommended.
LEAF AREA REDUCTION IN CORN GROWN IN A TROPICAL REGION OF BRAZIL AND ITS EFFECTS ON AGRONOMIC TRAITS
Resumo:
Global climate change may reduce leaf area in crop plants due to factors such as increasing occurrence of pests and diseases. The aim of this work was to estimate the impact of leaf area reduction on agronomic traits in corn. An experiment simulating leaf area reduction was carried out in a tropical region of Brazil. The agronomic performance of corn plants was evaluated at different percentages of leaf loss. It was observed that leaf area reductions over 41.01% significantly harm yield, mass of 1000 grains, cob density, and stem and root quality Crop improvement programs should take into account the development of genotypes resistant to factors that cause leaf area reduction in tropical crops.
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The striped-legged hermit Crab Clibanarius vittatus, with a geographical distribution covering a wide range Of latitudes in the western Atlantic, was selected for a comparative study on population features between two different areas of the Brazilian coast that are separated by approximately 3000 km. The two populations Were sampled concurrently for nine months. The populations in northern and southeastern Brazil showed different profiles in terms of size of specimens, sex ratio, and shell occupation. The observed plasticity of these life-cycle traits of C. vittatus in relation to local environmental conditions is discussed. (C) 2009 Elsevier Masson SAS. All rights reserved
Resumo:
There is evidence of personality disorders in patients with juvenile myoclonic epilepsy (JME). To date, there have been no published quantitative studies on personality traits in JME. The aim of the work described here was to study a group of patients with JME and quantitatively measure personality traits. We evaluated 42 patients (mean age: 26.57 years, SD: 8.38) and 42 controls (mean age: 26.96, SD: 8.48) using a validated personality inventory, the Temperament and Character Inventory (TCI). We applied two scores, one for the Beck Depression Inventory and one for the State-Trait-Anxiety Inventory, as depression and anxiety may impact the performance of these patients on the TCI. We compared both groups on TCI scales using analysis of covariance with Beck Depression Inventory and State-Trait-Anxiety Inventory scores as covariates. Patients with JME obtained significantly higher scores on Novelty Seeking (P=0.001) and Harm Avoidance (P=0.002) and significantly lower scores on Self-Directedness (P=0.001). Patients with JME have a higher expression of impulsive personality traits that demand early recognition to avoid further consequences and facilitate social insertion, consequently avoiding future stigma. (C) 2011 Elsevier Inc. All rights reserved.
Resumo:
Background: The objective of this study was to compare personality traits between major depressive disorder (MDD) patients and healthy comparison subjects (HC) and examine if personality traits in patients are associated with specific clinical characteristics of the disorder. Methods: Sixty MDD patients (45 depressed, 15 remitted) were compared to 60 HC using the Temperament and Character Inventory. Analysis of covariance, with age and gender as covariates, was used to compare the mean Temperament and Character Inventory scores among the subject groups. Results: Depressed MDD patients scored significantly higher than HC on novelty seeking, harm avoidance, and self-transcendence and lower on reward dependence, self-directedness, and cooperativeness. Remitted MDD patients scored significantly lower than HC only on self-directedness. Comorbidity with anxiety disorder had a main effect only on harm avoidance. Harm avoidance was positively correlated with depression intensity and with number of episodes. Self-directedness bad an inverse correlation with depression intensity. Conclusions: MDD patients present a different personality profile from HC, and these differences are influenced by mood state and comorbid anxiety disorders. When considering patients who have been in remission for some time, the differences pertain to few personality dimensions. Cumulated number of depressive episodes may result in increased harm avoidance. Depression and Anxiety 26.382-388, 2009. (c) 2009 Wiky-Liss, Inc.
Resumo:
Temperament and character traits may determine differences in clinical presentations and outcome of bipolar disorder. We compared personality traits in bipolar patients and healthy individuals using the Temperament and Character Inventory (TCI) and sought to verify whether comorbidity with alcoholism or anxiety disorders is associated with specific personality traits. Seventy-three DSM-IV bipolar patients were compared to 63 healthy individuals using the TCI. In a second step, the bipolar sample was subgrouped according to the presence of psychiatric comorbidity (alcoholism, n = 10; anxiety disorders; n = 23; alcoholism plus anxiety disorders, n = 21; no comorbidity, n = 19). Bipolar patients scored statistically higher than the healthy individuals on novelty seeking, harm avoidance and self-transcendence and lower on self-directedness and cooperativeness. Bipolar patients with only comorbid alcoholism scored statistically lower than bipolar patients without any comorbidity on persistence. Bipolar patients with only comorbid anxiety disorders scored statistically higher on harm avoidance and lower on self-directedness than bipolar patients without any comorbidity. Limitations of this study include the cross-sectional design and the small sample size, specifically in the analysis of the subgroups. However, our results suggest that bipolar patients exhibit a different personality structure than healthy individuals and that presence of psychiatric comorbidity in bipolar disorder is associated with specific personality traits. These findings suggest that personality, at least to some extent, mediates the comorbidity phenomena in bipolar disorder. (C) 2007 Elsevier Ltd. All rights reserved.
Resumo:
The total meat yield in a beef cattle production cycle is economically very important and depends on the number of calves born per year or birth season, being directly related to reproductive potential. Accumulated Productivity (ACP) is an index that expresses a cow`s capacity to give birth regularly at a young age and to wean animals of greater body weight. Using data from cattle participating in the ""Program for Genetic Improvement of the Nelore Breed"" (PMGRN - Nelore Brasil), bi-trait analyses were performed using the Restricted Maximum Likelihood method based on an ACP animal model and the following traits: age at first calving (AFC), female body weight adjusted for 365 (BW365) and 450 (BW450) days of age, and male scrotal circumference adjusted for 365 (SC365), 450 (SC450), 550 (SC550) and 730 (SC730) days of age. Median estimated ACP heritability was 0.19 and the genetic correlations with AFC, BW365, BW450, SC365, SC450, SC550 and SC730 were 0.33, 0.70, 0.65, 0.08, 0.07, 0.12 and 0.16, respectively. ACP increased and AFC decreased over time, revealing that the selection criteria genetically improved these traits. Selection based on ACP appears to favor the heaviest females at 365 and 450 days of age who showed better reproductive performance as regards AFC. Scrotal circumference was not genetically associated with ACP. (C) 2007 Elsevier B.V. All rights reserved.
Resumo:
The aim of the present study was to evaluate the genetic correlations among real-time ultrasound carcass, BW, and scrotal circumference (SC) traits in Nelore cattle. Carcass traits, measured by real-time ultrasound of the live animal, were recorded from 2002 to 2004 on 10 farms across 6 Brazilian states on 2,590 males and females ranging in age from 450 to 599 d. Ultrasound records of LM area (LMA) and backfat thickness (BF) were obtained from cross-sectional images between the 12th and 13th ribs, and rump fat thickness (RF) was measured between the hook and pin bones over the junction between gluteus medius and biceps femoris muscles. Also, BW (n = 22,778) and SC ( n = 5,695) were recorded on animals born between 1998 and 2003. The BW traits were 120, 210, 365, 450, and 550-d standardized BW (W120, W210, W365, W450, and W550), plus BW (WS) and hip height (HH) on the ultrasound scanning date. The SC traits were 365-, 450-, and 550-d standardized SC (SC365, SC450, and SC550). For the BW and SC traits, the database used was from the Nelore Breeding Program-Nelore Brazil. The genetic parameters were estimated with multivariate animal models and REML. Estimated genetic correlations between LMA and other traits were 0.06 (BF), -0.04 ( RF), 0.05 (HH), 0.58 (WS), 0.53 (W120), 0.62 (W210), 0.67 (W365), 0.64 ( W450 and W550), 0.28 (SC365), 0.24 (SC450), and 0.00 ( SC550). Estimated genetic correlations between BF and with other traits were 0.74 ( RF), -0.32 (HH), 0.19 (WS), -0.03 (W120), -0.10 (W210), 0.04 (W365), 0.01 (W450), 0.06 ( W550), 0.17 (SC365 and SC450), and -0.19 (SC550). Estimated genetic correlations between RF and other traits were -0.41 (HH), -0.09 (WS), -0.13 ( W120), -0.09 ( W210), -0.01 ( W365), 0.02 (W450), 0.03 (W550), 0.05 ( SC365), 0.11 ( SC450), and -0.18 (SC550). These estimates indicate that selection for carcass traits measured by real-time ultrasound should not cause antagonism in the genetic improvement of SC and BW traits. Also, selection to increase HH might decrease subcutaneous fat as correlated response. Therefore, to obtain animals suited to specific tropical production systems, carcass, BW, and SC traits should be considered in selection programs.
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Farnesoic acid O-methyl transferase (FAMeT) is the enzyme that catalyzes the formation of methyl farnesoate (MF) from farnesoic acid (FA) in the biosynthetic pathway of juvenile hormone (JH). This work reports the cloning, sequencing, and expression of FAMeT gene from the stingless bee Melipona scutellaris (MsFAMeT). The MsFAMeT in silica analysis showed that greatest sequence similarity is found in Apis mellifera and other insects, while relatively less similarity is shown in crustaceans. Evidence of alternative splicing of a 27 nucleotide (nt) microexon explains the presence of the detected isoforms, 1 and 2. The expression analysis of the two isoforms showed a marked difference when castes were compared, suggesting that they could be involved differently in the JH metabolism in M. scutellaris, providing new insights for the comprehension of female plasticity.
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The vomeronasal system is crucial for social and sexual communication in mammals. Two populations of vomeronasal sensory neurons, each expressing G alpha i2 or G alpha o proteins, send projections to glomeruli of the rostral or caudal accessory olfactory bulb, rAOB and cAOB, respectively. In rodents, the G alpha i2- and G alpha o-expressing vomeronasal pathways have shown differential responses to small/volatile vs. large/non-volatile semiochemicals, respectively. Moreover, early gene expression suggests predominant activation of rAOB and cAOB neurons in sexual vs. aggressive contexts, respectively. We recently described the AOB of Octodon degus, a semiarid-inhabiting diurnal caviomorph. Their AOB has a cell indentation between subdomains and the rAOB is twice the size of the cAOB. Moreover, their AOB receives innervation from the lateral aspect, contrasting with the medial innervation of all other mammals examined to date. Aiming to relate AOB anatomy with lifestyle, we performed a morphometric study on the AOB of the capybara, a semiaquatic caviomorph whose lifestyle differs remarkably from that of O. degus. Capybaras mate in water and scent-mark their surroundings with oily deposits, mostly for male-male communication. We found that, similar to O. degus, the AOB of capybaras shows a lateral innervation of the vomeronasal nerve, a cell indentation between subdomains and heterogeneous subdomains, but in contrast to O. degus the caudal portion is larger than the rostral one. We also observed that four other caviomorph species present a lateral AOB innervation and a cell indentation between AOB subdomains, suggesting that those traits could represent apomorphies of the group. We propose that although some AOB traits may be phylogenetically conserved in caviomorphs, ecological specializations may play an important role in shaping the AOB.
Resumo:
Whether contemporary human populations are still evolving as a result of natural selection has been hotly debated. For natural selection to cause evolutionary change in a trait, variation in the trait must be correlated with fitness and be genetically heritable and there must be no genetic constraints to evolution. These conditions have rarely been tested in human populations. In this study, data from a large twin cohort were used to assess whether selection Will cause a change among women in contemporary Western population for three life-history traits: age at menarche, age at first reproduction, and age at menopause. We control for temporal variation in fecundity (the baby boom phenomenon) and differences between women in educational background and religious affiliation. University-educated women have 35% lower fitness than those with less than seven years education, and Roman Catholic women have about 20% higher fitness than those of other religions. Although these differences were significant, education and religion only accounted for 2% and 1% of variance in fitness, respectively. Using structural equation modeling, we reveal significant genetic influences for all three life-history traits, with heritability estimates of 0.50, 0.23, and 0.45, respectively. However, strong genetic covariation with reproductive fitness could only be demonstrated for age at first reproduction, with much weaker covariation for age at menopause and no significant covariation for age at menarche. Selection may, therefore, lead to the evolution of earlier age at first reproduction in this population. We also estimate substantial heritable variation in fitness itself, with approximately 39% of the variance attributable to additive genetic effects, the remainder consisting of unique environmental effects and small effects from education and religion. We discuss mechanisms that could be maintaining such a high heritability for fitness. Most likely is that selection is now acting on different traits from which it did in pre-industrial human populations.
Resumo:
Short versions of four Eysenck personality scales had been included in questionnaires given to several adult samples from the Australian Twin Registry, comprising altogether some 5400 pairs. Means and regressions with age are compared for three samples at average ages of 23, 37, and 61 years, and for two samples of retested individuals, one tested twice at average ages of 29 and 37 years, and one tested three times at average ages of 45, 56, and 62 years, For both males and females the trends for Psychoticism (P), Extraversion (E), and Neuroticism (N) were generally downward with age, and for Lie (L), upward. However, in the longitudinal sample between ages 56 and 62 the trends for P, E, and I stopped or reversed, although N continued downward. Heritabilities were reasonably stable across age for P, E, and N, and the effects of shared environments negligible, but L showed some influence of shared environment as well as genes in all but the oldest age group. (C) 2001 Elsevier Science Ltd. All rights reserved.