Effect of ionizing radiation in dental enamel organic matrix formation

Orientador: Solange Maria de AlmeidaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O objetivo nesse trabalho foi avaliar a taxa de erupção dentária, a birrefringência da matriz orgânica do esmalte, a morfologia dos tecidos odontogênicos e a ultraestrutura do ameloblasto secretor em incisivos de ratos submetidos à altas doses de radiação X. Para isso foram utilizados, no total, sessenta ratos machos, sendo os primeiros trinta divididos em três grupos experimentais: Controle, Irradiado 15Gy e Irradiado 25Gy, grupos nos quais os animais receberam doses únicas de 15Gy e 25Gy de radiação X, respectivamente, localizada na região de cabeça e pescoço. A mensuração da taxa de erupção dentária foi realizada a cada dois dias, perfazendo o tempo total do experimento (seis dias e meio). Com o objetivo de acompanhar o desenvolvimento dentário por um período maior, utilizou-se mais trinta animais que foram submetidos ao mesmo tipo de tratamento e, portanto, divididos nos três grupos supracitados. Os valores da taxa de erupção foram submetidos à análise de variância e teste de Tukey (p<0,05). Todos os animais sacrificados aos seis dias e meio foram perfundidos, as hemimaxilas removidas, adequadamente fixadas e processadas de acordo com o protocolo de histologia da FOP-UNICAMP. Para birrefringência, mediu-se o valor do retardo óptico da área de maior brilho utilizando microscópio de polarização. Os dados foram encaminhados à análise estatística de variância e teste de Tukey (p<0,05). Para avaliação da morfologia dos tecidos odontogênicos e ultraestrutura celular foi realizada análise descritiva. Foi possível observar, nos grupos irradiados, uma redução significativa da taxa de erupção a partir do quarto dia. Uma diminuição no brilho de birrefringência foi encontrada nos grupos irradiados em relaçao ao controle, porém esta só foi significante para o grupo Irradiado 25Gy. A avaliação dos tecidos odontogênicos revelou, no grupo controle, região odontogênica com aspecto de normalidade e camada de odontoblastos e ameloblastos preservados. Nos grupos irradiados foi possível constatar desorganização das células da região odontogênica, camada de pré ameloblastos com redução na sua altura e odontoblastos muitas vezes ausentes ou pobremente organizados. A análise ultraestrutural revelou em todos os grupos, a presença de organelas íntegras, assim como processo de Tomes bem preservados. Evidenciou-se também a presença de filamentos em contato com as organelas citoplasmáticas. Entretanto, nos grupos irradiados, foram visualizadas diversas áreas de degeneração e a presença dos autofagossomas, sugerindo um processo de morte celular. Baseados nesses resultados, pôde-se concluir que altas doses de radiação X foram capazes de retardar a erupção dentária a partir do quarto dia; reduzir a birrefringência da matriz orgânica do esmalte na fase de secreção da amelogênese; alterar significativamente a morfologia dos tecidos odontogênicos e causar agressão, modificando a ultraestrutura celular.Abstract: The aim of this study was to evaluate the dental eruption rate, the organic enamel matrix birefringence, the odontogenic tissue morphology and the ultrastructure of secretory ameloblasts in incisor of rats submitted to high radiation doses. For this purpose, sixty male rats were used, the first thirty divided into three experimental groups: Control, 15Gy and 25Gy irradiated groups, which received single doses of 15 and 25Gy of X-rays, respectively, localized in the head and neck region. The measurement of the eruption rate was performed every two days, until the total experimental time was reached (six days and half). As an attempt of analyzing the dental development for a longer period, thirty other animals were used, divided into the same three experimental groups and submitted to the same procedure described above. The eruption rate values were submitted to ANOVA and Tukey test (p<0.05). All the animals tested in the sixth day and half were perfused, their hemimaxilla removed, adequately fixed and processed according to the histological protocol of FOP-UNICAMP. For birefringence analysis, the optical retardation was measured in the highest birefringence brightness area, using a polarizing microscope. Data were submitted to statistical analysis (ANOVA) and Tukey test (p<0.05). A descriptive analysis was performed for morphologic and ultrastructural evaluation. It was possible to observe, in irradiated groups, a significant reduction in the eruption rate from the fourth day. A reduction in the birefringence brightness was encountered in the irradiated groups in relation to control; this difference was, however, only significant to 25Gy irradiated group. The odontogenic tissue morphology analysis showed, in control group, odontogenic region with normal features and preserved layer of odontoblasts and ameloblasts. Both irradiated groups presented odontogenic cells disorganization, preameloblasts layer reduced in height and odontoblasts absent or poorly organized. The ultrastructural evaluation showed, in all the examined groups, the presence of organelles and Tomes process preserved. The presence of filaments in contact with the cytoplasmatic organelles was also found. However, in the irradiated groups several degeneration areas and autophagosomes were observed, suggesting a cell death process. Based on these results, it was possible to conclude that high radiation doses were capable to delay the eruption rate from the fourth day; to reduce the birefringence brightness of the organic matrix in the secretory stage of amelogenesis; to alter significantly the odontogenic tissues morphology and to cause aggression, modifying the cellular ultrastructure.DoutoradoRadiologia OdontologicaDoutor em Radiologia Odontológic

Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

Search for stop and higgsino production using diphoton Higgs boson decays

Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass

Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

Peer reviewe

Search for long-lived particles decaying to jets with displaced vertices in proton-proton collisions at root s=13 Te V

A search is presented for long-lived particles produced in pairs in proton-proton collisions at the LHC operating at a center-of-mass energy of 13 TeV. The data were collected with the CMS detector during the period from 2015 through 2018, and correspond to a total integrated luminosity of 140 fb(-1). This search targets pairs of long-lived particles with mean proper decay lengths between 0.1 and 100 mm, each of which decays into at least two quarks that hadronize to jets, resulting in a final state with two displaced vertices. No significant excess of events with two displaced vertices is observed. In the context of R-parity violating supersymmetry models, the pair production of long-lived neutralinos, gluinos, and top squarks is excluded at 95% confidence level for cross sections larger than 0.08 fb, masses between 800 and 3000 GeV, and mean proper decay lengths between 1 and 25 mm.Peer reviewe

Measurement of the W gamma Production Cross Section in Proton-Proton Collisions at root s=13 TeV and Constraints on Effective Field Theory Coefficients

A fiducial cross section for W gamma production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137 fb(-1) of data collected using the CMS detector at the LHC. The W -> e nu and mu nu decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum chromodynamics. In addition, 95% confidence level intervals are reported for anomalous triple-gauge couplings within the framework of effective field theory.Peer reviewe