RENATO SEMMLER

RENATO SEMMLER

(Fonte: Lattes)

Resumo

Graduado em Física pela Pontifícia Universidade Católica de São Paulo (1989), Mestre em Tecnologia Nuclear pela Universidade de São Paulo (1993) e Doutor em Tecnologia Nuclear pela Universidade de São Paulo (2006). Atualmente é pesquisador da Comissão Nacional de Energia Nuclear (CNEN), lotado no Centro do Reator de Pesquisas (CERPq) do Instituto de Pesquisas Energéticas e Nucleares (IPEN). Docente da pós-graduação stricto sensu - Programa de tecnologia nuclear do IPEN - Universidade de São Paulo e da pós-graduação stricto sensu - Mestrado profissional de tecnologia das radiações na saúde. Tem experiência na área de Física Nuclear de baixas energias atuando nos seguintes temas: reações de captura de nêutrons térmicos (prompt gamma rays), método k0 de análise por ativação neutrônica, caracterização do espectro de nêutrons junto aos canais de irradiação do reator IEA-R1, espectroscopia gama, fotodesintegração, reações fotonucleares (fotofissão e fotonêutrons) e ensino de física. Professor e organizador da EAEN - Escola Avançada de Energia Nuclear para estudantes do Ensino Médio, preferencialmente envolvidos com olimpíadas de física e química: Teoria e Aplicações das Ciências Nucleares. Professor de física com mais de 25 anos de experiência em cursos universitários, pré-vestibular e ensino médio. (Texto extraído do Currículo Lattes em 27 dez. 2021)

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Effects of gamma radiation on the pBs-KS DNA plasmid
2001 - ARRUDA NETO, J.D.T.; SHTEJER, K.; ZAMBONI, C.B.; DUARTE, C.L.; SEMMLER, R.; JORGE, S.A.C.; GOUVEIA, A.N.; DEPPMAN, A.; ARAUJO, G.W.
Effects of gamma radiation on the pBs-KS DNA plasmid
2001 - ARRUDA NETO, J.D.T.; ZAMBONI, C.B.; DUARTE, C.L.; SEMMLER, R.; JORGE, S.A.C.; ARAUJO, G.W.; SHTEJER, K.; GOUVEIA, A.N.; DEPPMAN, A.; HELENE, O.A.M.; VANIN, V.R.; LIKHACHEV, V.P.; MANSO GUEVARA, M.V.; MIRANDA, A.; RODRIGUEZ, O.
DNA is considered to be the most important and critical target in a cell from the point of view of radiation damage. It is responsible for conservation and transmission of all the cell genetic information. It is constantly submitted to different kind of damages, where repair could or couldn't take place. The energy transferred by ionizing radiation to the DNA strands can induce mutation, carcinogenic process and cell death. The DNA damage involves nucleotide base alterations, single (SSB) and double (DSB) strand breaks and also chromatin rupture. The DNA strand break (mainly DSB) is the most critical damage induced by ionizing radiation. Specifically. gamma radiation is used in a large number of illness treatment including cancer diagnosis, treatment and cure. In fact, this radiation is the base of conventional radiotherapy using ®9Co and ?%7Cs sources. Beside, this radiation is also present in treatment which involves neutrons and others types of particles, such as protons, alphas and heavy ions ( e.g. Ne. Ar). The 250 MeV proton beam therapy, largely used in recent years as an effective non invasive cancer treatment. produces gamma rays as a secondary radiation which can generate radiobiological effects on healthy tissue. This kind of radiation with low linear energy transfer (LET) interacts with the tissue producing secondary electrons. which directly produce excited and ionized states into the DNA strands and inducing the formation of energetic free radicals in the aqueous solution containing the DNA molecule. The DNA strand damages produced by these interactions must be well known in order to prevent the radiobiological effects on human being The investigation of DNA radiation effects has been very intensive in the last years!'=3), and the present study is a contribution to better understand the mechanism of single (SSB) and double (DSB) strand breaks of pBs KS (+) plasmid DNA with 1 MeV gamma radiation. About 10 ml of DNA was irradiated at a concentration of 15 ng/ml in a cylindrical plastic tube (eppendorf) in the ®®Co Gamma Cell at IPEN ( Instituto de Pesquisas Energeticas e Nucleares, Sao Paulo) facility. The dose rate was 5 kGy/h, and the biological material was submitted to total doses ranging from 0 to 200 Gy. Supercoiled (FI),Circular (FII) and Linear (FIII) forms of the plasmid were separated by agarose gel electrophoresis at 10 volts overnight with 1% agarose. The results exhibit a decreasing of the FI plasmid fraction and an increasing number of the FII and FIII fractions with the dose, suggesting the presence of SSBs and DSBs in the irradiated DNA plasmid. The detectable molecule fractions of each form of plasmid were analyzed by means of a statistical treatment[%) allowing the calculation of the average number of SSB and DSB per plasmid for each interaction dose.These two quantities are shown in the figure. The curve is only to guide the eyes(preliminary data). In this analysis it was assumed that the strand break distribution obeys Poisson' laws. These calculations were compared with the corresponding experimental data. It was found that the statistical results describe satisfactory the data for gamma radiation.
Estudio de danos inducidos en DNA por la radiacion: propuesta de proyecto tematico y multidisciplinario
2001 - ARRUDA NETO, J.D.T.; DEPPMAN, A.; LIKHACHEV, V.P.; GOUVEIA, A.N.; HELENE, O.A.M.; VANIN, V.R.; MESA HORMAZA, J.; ALVES, E.; BRINGAS GUTIERREZ, F.; MANSO GUEVARA, M.V.; PEREIRA FILHO, J.W.; SHTEJER, K.; DUARTE, C.L.; SEMMLER, R.; ZAMBONI, C.B.; JORGE, S.A.C.; ARAUJO, G.W.; MIRANDA, A.; RODRIGUEZ, O.; GUZMAN, F.
Photoneutron cross sections measurements in sup(9)Be with thermal neutron capture gamma-ray
2006 - SEMMLER, R.; CARBONARI, A.W.; GONCALEZ, O.L.
Deconvolucao de medidas de seccoes de choque fotonucleares com raios gama de captura de neutrons termicos
2000 - GONCALEZ, O.L.; SEMMLER, R.; GERALDO, L.P.
Espectroscopia gama nos niveis excitados de sup(155)Eu
2002 - GENEZINI, F.A.; ZAMBONI, C.B.; SEMMLER, R.; CRUZ, M.T.F.; ZEVALLOS CHAVEZ, J.Y.; DIAS, H.
The continuous development of composites is essential to provide the adequacy of their properties to innumerable applications, either in medicine or in civil construction areas. Previous studies were concerned to a pre-polimerization of acrylic mixtures, in order to hinder the decantation of inorganic charges via irradiation. The success of the experiment, confirmed by MEV inspections, fostered the continuity of trials, by assessing too polyester resin and its combination with acrylics and inorganic loads, all of formulations being subjected to gamma radiation, within 3.0 to 15 kGy doses. Gel extractions tests indicated a trend for higher performance in terms of crosslinking, for samples containing inorganic charges. Within 7.5 to 15 kGy doses, samples containing polyester presented excellent results for gel extraction: 84.65 to 95.19%, when compared to samples comprising just acrylics. Samples comprising acrylics, irradiated at 3.0 kGy, failed when tested as per gel extraction, i.e., dissolved completely in acetone, solvent commonly used for the extraction. Furthermore, there will be required further assessments, for all combinations studied, besides investigating crosslinking agents, which showed a non-expected poor gel fraction results, when combined with acrylics. In addition, these crosslinking agents will be formulated with polyester resin, to complete the present study. Further evaluations will consider gamma radiation doses within a 3.0 – 7.5 kGy range.
Estudo do equilibrio eletronico no aluminio utilizando o dosimetro termoluminescente de CaSOsub(4):Dy
2002 - FEDERICO, C.A.; GERALDO, L.P.; GONCALEZ, O.L.; SEMMLER, R.; CALDEIRA, A.D.; RIGOLON, L.S.Y.
Photoneutron cross sections measurements in sup(13)C with thermal neutron capture gamma-rays
2007 - SEMMLER, RENATO; CARBONARI, ARTUR W.; GONCALEZ, ODAIR L.; TERREMOTO, LUIS A.A.
Medidas experimentais da taxa de energia absorvida no aluminio e comparacao com calculos utilizando fatores de dose e transporte de eletrons por meio do codigo MCNP
2000 - FEDERICO, C.A.; VIEIRA, W.J.; RIGOLON, L.S.Y.; GONCALEZ, O.L.; GERALDO, L.P.; SEMMLER, R.
Preliminary results for the K sub(0) INAA methodology implementation at the neutron activation analysis laboratory, LAN-IPEN, using K sub(0) IAEA software
2009 - MARIANO, DAVI B.; FIGUEIREDO, ANA M.G.; SEMMLER, RENATO