Fenologia, emergência, morfologia e produção de mudas de Emmotum nitens (Benth.) Miers

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Florestal, 2012.Emmotum nitens (Icacinaceae) é uma das espécies do bioma Cerrado com os maiores valores de índice de importância entre as ocorrentes em Cerradões de Latossolos distróficos, porém pouco é conhecido sobre a sua reprodução. Este trabalho foi realizado em dez indivíduos adultos nas proximidades da Reserva Ecológica Cerradão, onde as árvores foram georreferênciadas com auxílio de um aparelho GPS; Laboratório de Biologia Vegetal e Viveiro da Embrapa Cerrados, Planaltina – DF. Os objetivos deste trabalho foram: 1) Verificar o ciclo reprodutivo da espécie através de suas fenofases. Os frutos de Emmotum nitens permaneceram por um longo período nos indivíduos adultos, com um efeito aparente de frutificação contínua, embora o que tenha ocorrido foram diferentes estádios de desenvolvimento, tamanho, amadurecimento e dispersão. 2) Realizar um protocolo de coleta e beneficiamento de frutos para a obtenção de diásporos e sementes isoladas. A imersão em água dos frutos por 48 horas proporcionou uma alteração da consistência do exocarpo (polpa) facilitando a remoção do mesmo. O tempo médio para beneficiar uma amostra de 100 frutos foi de ±15 min. ou 2 horas e trinta minutos para beneficiar (1000) mil frutos; o uso de um dispositivo metálico desenvolvido para a extração de sementes propiciou que estas fossem retiradas do interior dos diásporos intactas. 3) Verificar o efeito das condições fitossanitárias de diásporos e a viabilidade de sementes armazenadas em dois diferentes ambientes (câmara fria – CF e temperatura ambiente de laboratório - TA). Após o período de oito meses de armazenagem, através do teste de tetrazólio (1%), as sementes apresentaram uma viabilidade de 94 e 86% para TA e CF, respectivamente. 4) Avaliar através de experimentos em laboratório a emergência e desenvolvimento de plântulas a partir de diásporos e sementes isoladas. A porcentagem média de emergência a partir de sementes isoladas foi de 3 e 4% e 9 e 8%, para o primeiro e segundo experimentos montados em câmara de germinação a 25 °C, já a partir de diásporos nas mesmas condições, a germinação e emergência não ocorreu. 5) Ilustrar e caracterizar os aspectos morfométricos de frutos, diásporos, sementes e plântulas; onde foi caracterizado no fruto, diásporo e semente: O tamanho (comprimento, largura e espessura), características externas e internas, morfologia e tipo de germinação. Os frutos são do tipo drupóide, mesocarpos lenhosos, semente com embrião axial, cotilédones foliáceos e germinação fanerocotiledonar. As plântulas possuem protófilos simples, alternos e sistema radicular axial. As plântulas aos 180 dias atingiram uma média de 23,6 cm de altura e diâmetro do coleto de 2,36 mm. 6) Avaliar o crescimento em diferentes substratos (Solo de Cerradão; Solo de Cerradão + Areia e Solo Cerradão + Areia + Adubo); para a produção de mudas de Emmotum nitens. O delineamento experimental utilizado foi o DBC com 8 blocos x 3 tratamentos x 10 repetições. Foram avaliadas as medidas alométricas da parte aérea, da raiz, número de folhas, diâmetro do caule e a razão raiz/parte aérea. Na produção de matéria seca foi avaliada a massa seca da parte aérea, da raiz e a massa seca total. A emergência das plântulas de Emmotum nitens iniciou aos 28 dias após o plantio, estendo até os 95 dias. Não houve diferença significativa entre os tratamentos em relação às medidas de crescimento, número de folhas, diâmetro do coleto e na produção de massa seca total. O investimento de crescimento em raiz foi maior que o da parte aérea, porém, na produção de massa seca, o investimento na parte aérea foi o dobro em relação ao investimento na raiz. A espécie Emmotum nitens apresentou neste trabalho a produção de plântulas anômalas a partir de sementes isoladas; mas quando o plantio foi feito por diásporos (mesocarpos lenhosos + sementes) em condições de viveiro, obteve-se plantas normais. _________________________________________________________________________________ ABSTRACTEmmotum nitens (Icacinacea) is a species of the Cerrado biome with the highest importance index values among Cerradões occurring in the dystrophic Oxisols, but little is known about their reproduction. This work was carried out near Cerradão Ecological Reserve, where trees have been georeferenced with the aid of a GPS; Plant Biology Laboratory and Embrapa Cerrados Nursery, Planaltina - DF. Our objectives were: 1) Check the reproductive cycle of the species through their phenophases. The fruits of Emmotum nitens are remained for a long period in the adults, with an apparent effect of continuous fruiting, although that occurred were different stages of development, size, maturation and dispersal. 2) Undertake collection and processing of fruit to obtain seeds and diaspores isolated. The immersion of the fruits in water for 48 hours afforded a change exocarp consistency (pulp) facilitating is removal. The average time to receive a sample of 100 fruits was ± 15 min. or two hours and thirty minutes for receiving (1000) thousand fruits and a metallic device was developed to diaspores extract seeds provided they were removed intact from the interior of the seeds. 3) Check the plant health and viability of the seeds stored in two different environments (cold - CF and laboratory temperature - TA). After eight months of storage, through the tetrazolium test (1%), the seeds had a viability of 94 and 86% for TA and CF, respectively. 4) evaluate through experiments in the laboratory the emergence and development of seedlings from diaspores and isolated seeds. The average emergency percentage the isolated from 3 to 4% and 8 and 9%, for the first and second experiments in a germination chamber at 25 ° C, while the diasporas in the same conditions, no germination occurred. 5) Illustrate and characterize the morphometric aspects of fruits, diaspores, seeds and seedlings, which were characterized in the fruit, seed diaspore: The size (length, width and thickness), external and internal characteristics, morphology and germination type. The fruits are of the dripe type, woody mesocarps, seed with axial embryo foliaceous cotyledons and phanerocotylar germination. Seedlings have protophilus simple, alternate and root axial. The seedlings at 180 days averaged 23.6 cm in height and stem diameter of 2.36 mm. 6) Evaluate the seedlings growth E. nitens in different substrates (Solo Savana, Savana Soil and Soil + Sand + Sand + Savana fertilizer). The experimental design was a randomized block design with 8 blocks x 3 treatments x 10 replicates. Measures were evaluated for growth of shoot, root, leaf number, stem diameter and root / shoot. The dry weight of shoot, root and total dry mass was assessed. The seedling emergence Emmotum nitens began 28 days after planting, extended up to 95 days. There was no significant difference between treatments in relation to measures of growth, leaf number, stem diameter and total dry matter production. The investment in root growth was greater than that of the shoot, but in dry matter production, investment in the shoot was over twice the investment in the root. The species Emmotum nitens presented the anomalous production of seedlings from seeds isolated, but when the diaspores (woody mesocarps + seeds) in nursery conditions, were normal plants obtained

Restauração de Unidade Demonstrativa com o uso de Técnicas Nucleadoras em Mata Atlântica Estacional Semidecidual

O objetivo deste trabalho foi avaliar os efeitos de diferentes técnicas nucleadoras implantadas em uma unidade demonstrativa (área degradada), durante seus estádios sucessionais pelo período de um ano. As técnicas nucleadoras utilizadas foram: enleiramento de galharia, poleiros secos, transposição de solo e transposição de plântulas. O enleiramento de galharia se mostrou eficiente para o abrigo de espécies animais, e já em fase de decomposição, no aumento de matéria orgânica no solo. Os poleiros secos (arvores mortas em pé) foram visitados por 19 espécies de aves pertencentes a 11 famílias, num total de 222 indivíduos, sendo estes potenciais dispersores de sementes. A transposição de solo propiciou um expressivo aumento em número e diversidade de espécies vegetais no final do processo de restauração com implantação das técnicas nucleadoras, com uma densidade absoluta de 1240 indivíduos por hectare, com 33 espécies pertencentes a 18 famílias. A transposição de plântulas em grupos de Anderson na unidade demonstrativa se mostrou bastante eficaz, sendo que das 25 plântulas resgatadas na mata adjacente e plantadas diretamente na área, tiveram 100% de estabelecimento

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

Peer reviewe

An embedding technique to determine ττ backgrounds in proton-proton collision data

An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

Search for Physics beyond the Standard Model in Events with Overlapping Photons and Jets

Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with hadrons. The analyzed proton-proton collision data were collected by the CMS experiment at the LHC, in 2016 at root s = 13 TeV, and correspond to an integrated luminosity of 35.9 fb(-1). The spectra of total transverse hadronic energy of candidate events are examined for deviations from the standard model predictions. No statistically significant excess is observed over the expected background. The first cross section limits on new physics processes resulting in such events are set. The results are interpreted as upper limits on the rate of gluino pair production, utilizing a simplified stealth supersymmetry model. The excluded gluino masses extend up to 1.7 TeV, for a neutralino mass of 200 GeV and exceed previous mass constraints set by analyses targeting events with isolated photons.Peer reviewe

Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.

Calibration of the CMS hadron calorimeters using proton-proton collision data at root s=13 TeV

Methods are presented for calibrating the hadron calorimeter system of theCMSetector at the LHC. The hadron calorimeters of the CMS experiment are sampling calorimeters of brass and scintillator, and are in the form of one central detector and two endcaps. These calorimeters cover pseudorapidities vertical bar eta vertical bar ee data. The energy scale of the outer calorimeters has been determined with test beam data and is confirmed through data with high transverse momentum jets. In this paper, we present the details of the calibration methods and accuracy.Peer reviewe

Measurement of the Jet Mass Distribution and Top Quark Mass in Hadronic Decays of Boosted Top Quarks in pp Collisions at root s=13 TeV

A measurement is reported of the jet mass distribution in hadronic decays of boosted top quarks produced in pp collisions at root s = 13 TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 35.9 fb(-1). The measurement is performed in the lepton + jets channel of t (t) over bar events, where the lepton is an electron or muon. The products of the hadronic top quark decay t -> bW -> bq (q) over bar' are reconstructed as a single jet with transverse momentum larger than 400 GeV. The t (t) over bar cross section as a function of the jet mass is unfolded at the particle level and used to extract a value of the top quark mass of 172.6 +/- 2.5 GeV. A novel jet reconstruction technique is used for the first time at the LHC, which improves the precision by a factor of 3 relative to an earlier measurement. This highlights the potential of measurements using boosted top quarks, where the new technique will enable future precision measurements.Peer reviewe

Search for top squark pair production in a final state with two tau leptons in proton-proton collisions at root s=13 TeV

A search for pair production of the supersymmetric partner of the top quark, the top squark, in proton-proton collision events at s = 13 TeV is presented in a final state containing hadronically decaying tau leptons and large missing transverse momentum. This final state is highly sensitive to high-tan beta or higgsino-like scenarios in which decays of electroweak gauginos to tau leptons are dominant. The search uses a data set corresponding to an integrated luminosity of 77.2 fb(-1), which was recorded with the CMS detector during 2016 and 2017. No significant excess is observed with respect to the background prediction. Exclusion limits at 95% confidence level are presented in the top squark and lightest neutralino mass plane within the framework of simplified models, in which top squark masses up to 1100 GeV are excluded for a nearly massless neutralino.Peer reviewe