1,447 research outputs found
Terminal-repeat retrotransposons with GAG domain in plant genomes : a new testimony on the complex world of transposable elements
A novel structure of nonautonomous long terminal repeat (LTR) retrotransposons called terminal repeat with GAG domain (TR-GAG) has been described in plants, both in monocotyledonous, dicotyledonous and basal angiosperm genomes. TR-GAGs are relatively short elements in length (<4 kb) showing the typical features of LTR-retrotransposons. However, they carry only one open reading frame coding for the GAG precursor protein involved for instance in transposition, the assembly, and the packaging of the element into the virus-like particle. GAG precursors show similarities with both Copia and Gypsy GAG proteins, suggesting evolutionary relationships of TR-GAG elements with both families. Despite the lack of the enzymatic machinery required for their mobility, strong evidences suggest that TR-GAGs are still active. TR-GAGs represent ubiquitous nonautonomous structures that could be involved in the molecular diversities of plant genomes
Os sistemas agroflorestais como alternativa de sustentabilidade em ecossistemas de várzea no Amazonas.
Os sistemas agroflorestais (SAFs) representam uma alternativa agroecológica de produção, sob regime sustentável, para os agricultores familiares na várzea dos Rios Solimões/Amazonas, principalmente no que se refere ao manejo florestal, à diversidade de produtos e à geração de renda. Diante disso, o objetivo deste trabalho foi compreender as diferentes formas de apropriação e de manejo dos recursos naturais através dos SAFs, nos subsistemas roça, sítio e lagos, como componente para a sustentabilidade dos agricultores familiares da localidade Costa da Terra Nova, município do Careiro da Várzea, Amazonas. O método empregado foi o Estudo de Caso com aplicação de questionários, entrevistas e observação participante. A produção familiar na Costa da Terra Nova é representada pelos SAFs, constituído pelos os subsistemas: roça quintal e lago, que proporcionam produtos tanto para subsistência quanto para comercialização local, e estabelecendo a agricultura como fundamental atividade na localidade. O principal produto para comercialização é obtido das hortaliças cultivadas na época da vazante no subsistema roça nas comunidades São Francisco e Nossa Senhora da Conceição; e do extrativismo pesqueiro no subsistema lago, na época da cheia, principalmente na comunidade São José. A criação de animal se dá no subsistema sítio e é apenas para subsistência, sendo as aves e os suínos os principais animais domésticos criados nas três comunidades. Portanto os SAFs tradicionais, constituídos pelos subsistemas, roça, sitio e lago, são responsáveis pela sustentabilidade socioeconômica da localidade pesquisada, servindo, como alternativa agrícola melhor adaptada às condições locais das áreas de várzea na Amazônia
flavour tagging using charm decays at the LHCb experiment
An algorithm is described for tagging the flavour content at production of
neutral mesons in the LHCb experiment. The algorithm exploits the
correlation of the flavour of a meson with the charge of a reconstructed
secondary charm hadron from the decay of the other hadron produced in the
proton-proton collision. Charm hadron candidates are identified in a number of
fully or partially reconstructed Cabibbo-favoured decay modes. The algorithm is
calibrated on the self-tagged decay modes and using of data collected by the LHCb
experiment at centre-of-mass energies of and
. Its tagging power on these samples of
decays is .Comment: All figures and tables, along with any supplementary material and
additional information, are available at
http://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-027.htm
Evidence for the strangeness-changing weak decay
Using a collision data sample corresponding to an integrated luminosity
of 3.0~fb, collected by the LHCb detector, we present the first search
for the strangeness-changing weak decay . No
hadron decay of this type has been seen before. A signal for this decay,
corresponding to a significance of 3.2 standard deviations, is reported. The
relative rate is measured to be
, where and
are the and fragmentation
fractions, and is the branching
fraction. Assuming is bounded between 0.1 and
0.3, the branching fraction would lie
in the range from to .Comment: 7 pages, 2 figures, All figures and tables, along with any
supplementary material and additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-047.htm
Twin pregnancy in brazil: a profile analysis exploring population information from the national birth e-registry on live births
sem informaçãoBirth records as SINASC (Brazilian Live Birth Information System) are highlighted in uncommon conditions such as twin pregnancy whose prevalence rarely exceeds 2 to 3% of the total number of births. The objective of this study was to assess the prevalence110sem informaçãosem informaçãosem informaçã
Study of the production of and hadrons in collisions and first measurement of the branching fraction
The product of the () differential production
cross-section and the branching fraction of the decay () is
measured as a function of the beauty hadron transverse momentum, ,
and rapidity, . The kinematic region of the measurements is and . The measurements use a data sample
corresponding to an integrated luminosity of collected by the
LHCb detector in collisions at centre-of-mass energies in 2011 and in 2012. Based on previous LHCb
results of the fragmentation fraction ratio, , the
branching fraction of the decay is
measured to be \begin{equation*} \mathcal{B}(\Lambda_b^0\rightarrow J/\psi
pK^-)= (3.17\pm0.04\pm0.07\pm0.34^{+0.45}_{-0.28})\times10^{-4},
\end{equation*} where the first uncertainty is statistical, the second is
systematic, the third is due to the uncertainty on the branching fraction of
the decay , and the
fourth is due to the knowledge of . The sum of the
asymmetries in the production and decay between and
is also measured as a function of and .
The previously published branching fraction of , relative to that of , is updated.
The branching fractions of are determined.Comment: 29 pages, 19figures. All figures and tables, along with any
supplementary material and additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-032.htm
Síndrome De Transfusão Feto-fetal: Neurodesenvolvimento De Lactentes Tratados Com Cirurgia A Laser
To assess the neurodevelopmental functions of survivors of twin-twin transfusion syndrome (TTTS) treated by fetoscopic laser coagulation (FLC), during the first year of life, comparing them to a control group; and to verify the influence of specific variables on neurodevelopment. Method: This was a prospective, longitudinal study. The sample comprised 33 monochorionic diamniotic twins who underwent FLC for treatment of TTTS and 22 full-term infants of single-fetus pregnancies. Bayley Scales of Infant and Toddler Development Screening Test were used for evaluation. Prenatal, perinatal and postnatal information were obtained. Results: There was an increased frequency of infants in the TTTS group with inadequate performance compared to the control group. The identified variables (fetal donor, low economic income and cardiorespiratory disease) negatively impacted expressive communication and fine motor skills. Conclusion: Although through follow-up is recommended in all TTTS survivors, particular attention is required for the high-risk group as defined in this study. © 2016, Associacao Arquivos de Neuro-Psiquiatria. All rights reserved.74430731
Morphophysiological Plasticity Of Plagiotropic Branches In Response To Change In The Coffee Plant Spacing Within Rows
Changes in spacing within rows may alter the morphology of the coffee plant by affecting the physiological constituents of its productivity. Even though some common plant responses to crop spacing variation are known, there is yet no scientific evidence that elucidates the effects of decreased spacing on the sourcesink relation in plagiotropic branches and, its association with both productivity and eco-physiological aspects of coffee leaves, mainly for new coffee cultivars in the Brazilian savannah. The aim of this work was to characterize the morphophysiological responses of Coffea arabica L. cultivars subjected to different spacing between plants within rows. Four Arabica coffee cultivars (Catuaí Vermelho IAC 144, Catuaí Amarelo IAC 62, Catuaí Amarelo IAC 32, and Tupi RN IAC 1669-13) were transplanted in January 2010. A row spacing of 0.40, 0.50, 0.60, 0.70, and 0.80 m was adopted between plants, maintaining a 3.80-m constant between rows. A randomized block design with four replicates was applied. During the experimental period, several morphophysiological characteristics of plagiotropic fruiting branches were evaluated in the months of April and December in 2013 and, in April 2014. The evaluation was conducted based on two canopy positions; canopy toward the rows, representing low exposure to light or toward the inter-row spacing, representing high light exposure. Leaf gas exchange, chlorophyll fluorescence, and photosynthetic pigments levels were minimally or not at all affected by changing either the coffee cultivars or plant spacing. During the first evaluation, the leaf-to-fruitratio linearly increased, regardless of the cultivar. Light-exposed branches showed higher content of carotenoids and chlorophyll a in leaves and lower leaf-to-fruit-ratio as compared to those within the plant canopy. A major reduction in the number of fruits per branch was observed which was closely related to a parallel decrease in the number of fruits per node but not in the number of fruiting nodes per branch. Although this response was largely cultivar-dependent, it also changed according to the branch position in the hedgerow. Our results suggest that all tested cultivars exhibit high morphophysiological plasticity and have the potential to grow under different plant spacing within rows.3763819383
Influence of Distributed Energy Resources on Grid Voltage Quality using Model IEEE 13 busbars
Exclusive Studies of Charged-Particle Emission in 1-H and 3-He-Induced Reactions on Heavy Nuclei
This research was sponsored by the National Science Foundation Grant NSF PHY-931478
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