Novas formas de manejo integrado da traça-do-tomateiro.

bitstream/item/23625/1/villas-boas-novas.pd

On fermion masses and mixing in a model with A4A_4 symmetry

In a recently proposed multi-Higgs extension of the standard model in which discrete symmetries, $A_4$ and $Z_3$ are imposed we show that, after accommodating the fermion masses and the mixing matrices in the charged currents, the mixing matrices in the neutral currents induced by neutral scalars are numerically obtained. However, the flavor changing neutral currents are under control mainly by mixing and/or mass suppressions in the neutral scalar sector.Comment: Version accepted for publication in International Journal of Modern Physics A. In this version we added a discussion on the charged lepton and neutrino masses. The title has been changed. Other minor changes do not modify the conclusion

Avaliação da resistência a Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) e Euxesta sp. (Diptera: Otitidae) em linhagens de milho-doce.

Sixteen tines of sweet com were evaluated for resistance to Helicoverpa zea (Boddie) and Euxesta sp. Artificial and natural infestation of H. zea (Boddie) were used. The tines DCOl and DC03 were resistant to both pests. No difference was observed between artificial and natural infestation

Comparative outcome assessment of epidermal growth factor receptor tyrosine kinase inhibitors for the treatment of advanced non-small-cell lung cancer: A network meta-analysis

Introduction: Tyrosine kinase inhibition of the epidermal growth factor receptor (EGFR) is the standard in the first line treatment of patients with advanced nonsmall- cell lung cancer (NSCLC) harbouring EGFR activating mutations. Here we aim to discern efficacy and toxicity measures through a meta-analysis of published studies that could aid treatment selection. Materials And Methods: We performed a meta-analysis of the main randomized clinical trials evaluating the currently approved EGFR-TKIs in first-line of treatment of EGFR-positive advanced NSCLC. Cochrane guidelines were used for statistical analysis. Results: 3,179 patients were included. All EGFR TKIs showed improved outcomes with respect to ORR and PFS when compared to standard platinum-doublet chemotherapy. Comparative ORR for gefitinib, erlotinib and afatinib were 52.1%, 67.3% and 61.6% respectively. HRs for PFS were 0.62 (95% CI, 0.38-1.00) for gefitinib, 0.28 (95% CI, 0.17-0.45) for erlotinib and 0.40 (95% CI, 0.20-0.83) for afatinib. HRs for OS were not statistically significant for any agent. Conclusions: Our results suggest similar clinical efficacy and higher toxicity of Afatinib treatment. As this still remains the agent with best CSF penetration, we suggest its use is limited to patients presenting with brain metastasis. We suggest the use of Gefitinib in patients without CNS involvement. Faced with the impossibility to dose-reduce Gefitinib, Erlotinib represents a tolerable and effective alternative to Afatinib and Gefitinib if response to EGFR inhibition is considered still effective.Logistic provision from the Cearense School of Oncology, Ceará Cancer Institute, Haroldo Juaçaba Hospital, Fortaleza, Ceará, Brazil, and The Clatterbridge Cancer Centre NHS Foundation Trust, Wirral & Liverpool, England, United Kingdom. RAM has received honoraria from Pfizer Advisory Board, Zodiac advisory board, AstraZeneca, Novartis, National Science Centre, Krakow, Poland, and educational grant from Pierre Fabre, Amgem. RAM is ad hoc consultant at Ministry of Health, Brasília, Brazil. The other authors have no conflicts of interest in this manuscript. GM has received honoraria from Bristol Myers Squibb, Roche and AstraZeneca

Peripheral Attentional Targets under Covert Attention Lead to Paradoxically Enhanced Alpha Desynchronization in Neurofibromatosis Type 1

The limited capacity of the human brain to process the full extent of visual information reaching the visual cortex requires the recruitment of mechanisms of information selection through attention. Neurofibromatosis type-1 (NF1) is a neurodevelopmental disease often exhibiting attentional deficits and learning disabilities, and is considered to model similar impairments common in other neurodevelopmental disorders such as autism. In a previous study, we found that patients with NF1 are more prone to miss targets under overt attention conditions. This finding was interpreted as a result of increased occipito-parietal alpha oscillations. In the present study, we used electroencephalography (EEG) to study alpha power modulations and the performance of patients with NF1 in a covert attention task. Covert attention was required in order to perceive changes (target offset) of a peripherally presented stimulus. Interestingly, alpha oscillations were found to undergo greater desynchronization under this task in the NF1 group compared with control subjects. A similar pattern of desynchronization was found for beta frequencies while no changes in gamma oscillations could be identified. These results are consistent with the notion that different attentional states and task demands generate different patterns of abnormal modulation of alpha oscillatory processes in NF1. Under covert attention conditions and while target offset was reported with relatively high accuracy (over 90% correct responses), excessive desynchronization was found. These findings suggest an abnormal modulation of oscillatory activity and attentional processes in NF1. Given the known role of alpha in modulating attention, we suggest that alpha patterns can show both abnormal increases and decreases that are task and performance dependent, in a way that enhanced alpha desynchronization may reflect a compensatory mechanism to keep performance at normal levels. These results suggest that dysregulation of alpha oscillations may occur in NF1 both in terms of excessive or diminished activation patterns

Out-of-phase oscillation between superfluid and thermal components for a trapped Bose condensate under oscillatory excitation

The vortex nucleation and the emergence of quantum turbulence induced by oscillating magnetic fields, introduced by Henn E A L, et al. 2009 (Phys. Rev. A 79, 043619) and Henn E A L, et al. 2009 (Phys. Rev. Lett. 103, 045301), left a few open questions concerning the basic mechanisms causing those interesting phenomena. Here, we report the experimental observation of the slosh dynamics of a magnetically trapped $^{87}$Rb Bose-Einstein condensate (BEC) under the influence of a time-varying magnetic field. We observed a clear relative displacement in between the condensed and the thermal fraction center-of-mass. We have identified this relative counter move as an out-of-phase oscillation mode, which is able to produce ripples on the condensed/thermal fractions interface. The out-of-phase mode can be included as a possible mechanism involved in the vortex nucleation and further evolution when excited by time dependent magnetic fields.Comment: 5 pages, 5 figures, 25 reference

The non-coding snRNA 7SK controls transcriptional termination, poising, and bidirectionality in embryonic stem cells

BACKGROUND: Pluripotency is characterized by a unique transcriptional state, in which lineage-specification genes are poised for transcription upon exposure to appropriate stimuli, via a bivalency mechanism involving the simultaneous presence of activating and repressive methylation marks at promoter-associated histones. Recent evidence suggests that other mechanisms, such as RNA polymerase II pausing, might be operational in this process, but their regulation remains poorly understood. RESULTS: Here we identify the non-coding snRNA 7SK as a multifaceted regulator of transcription in embryonic stem cells. We find that 7SK represses a specific cohort of transcriptionally poised genes with bivalent or activating chromatin marks in these cells, suggesting a novel poising mechanism independent of Polycomb activity. Genome-wide analysis shows that 7SK also prevents transcription downstream of polyadenylation sites at several active genes, indicating that 7SK is required for normal transcriptional termination or control of 3′-UTR length. In addition, 7SK suppresses divergent upstream antisense transcription at more than 2,600 loci, including many that encode divergent long non-coding RNAs, a finding that implicates the 7SK snRNA in the control of transcriptional bidirectionality. CONCLUSIONS: Our study indicates that a single non-coding RNA, the snRNA 7SK, is a gatekeeper of transcriptional termination and bidirectional transcription in embryonic stem cells and mediates transcriptional poising through a mechanism independent of chromatin bivalency.GCB was funded by an EMBO Long-Term Post-Doctoral Fellowship and a Marie Curie Intra-European Fellowship for Career Development. PA was supported by a Royal Society Newton International Fellowship and a Corpus Christi College research fellowship. This work was supported by Cancer Research UK, European Research Council (Advanced Grant, TK), EMBL (PB) and Swedish Research Council (GCB)