89 results on '"Medeiros, Diogo"'
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2. New methods for data analysis of complex chemical systems with practical applications for atmospheric studies
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de Jesus Medeiros, Diogo and Seakins, Paul W.
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540 - Abstract
The hydroxyl radical, OH, is the most important oxidizing agent in the troposphere during daylight periods. This radical, which is predominantly produced from the photolysis of ozone initiates the gas-phase oxidation of the vast majority of volatile organic compounds emitted in the atmosphere. This thesis is focused on the development and exploitation of useful methods of analysis for the study of atmospherically-relevant processes via direct OH measurements. However, the flexibility of the technique makes it also suitable for the study of high temperature combustion-related chemistry. For example, OH recycling can be an important process for the high temperature oxidation of ethers, a class of oxygenated species often used as fuel additives. Such methods provide the necessary tools for the exploration of complex competing processes, stretching the limits of the conventional bimolecular analysis for measuring rate coefficients. Among them, a new method based on Master Equation calculations via global analysis allows the direct analysis of the temporal evolution of OH radicals undergoing temperature and pressure dependent processes. Such unprecedented analysis can not only provide mechanistic information, but also enables a robust evaluation of the thermochemistry of elementary reactions. The method is very useful in situations where a reaction of interest cannot be isolated from competing processes, as required by conventional analysis techniques. For example, for the high temperature oxidation of alkenes which involve both an OH addition and a hydrogen abstraction mechanism, the global technique is capable of discriminating and quantifying the contribution of each channel. The reaction of OH radicals with sulphur dioxide (SO2) was investigated via classical Master Equation analysis. The role of a weakly bound pre-reaction complex formation (~7.2 kJ mol^-1) was tested and a comparison of Leeds experimental data with the literature was undertaken. The results indicated that the pre-reaction complex formation is not significant under atmospheric conditions and much of literature data may have been influenced by secondary chemistry associated with SO2 photolysis. A transition state submerged below the reagents ( 1.0 kJ mol^-1) was required to describe the Leeds measurements, which appear to be more consistent than the rest of the literature. The analysis of high temperature equilibration data (OH + SO2 ⇄ HO-SO2), allowed the enthalpy of reaction to be determined (110.5 ± 6.6 kJ mol^-1). This experimental determination is in excellent agreement with the highest-level theoretical predictions found in the literature (~111.5 kJ mol^-1). The OH + isoprene reaction in the absence of oxygen was explored over a wide range of temperatures (298-794 K) and pressures (~60-1500 Torr). At high enough temperatures (T > 700 K), direct observations of the established isoprene + OH ⇄ isoprene-OH equilibrium were collected. The study also generated unprecedented rate coefficients which were subsequently employed for the study of OH recycling in the presence of O2. The equilibration data were exploited via a bi-exponential analysis of both experimental and Master Equation-simulated traces and used for the determination of the well-depth for OH addition to carbon C1 (153.5 ± 6.2 kJ mol^-1), which is in excellent agreement with our theoretically derived estimate (154.1 kJ mol^-1). This experimental value, however, is dependent on the level of theory at which the vibrational modes of the involved species are treated. The equilibration data also indicated a significant OH loss in the system, incompatible with the reaction of OH with its precursor or diffusion. This process was rationalized as a competing hydrogen abstraction, which interfered in the non-exponential equilibration traces. A global analysis of the data was capable of extracting information about both the OH addition (k_addition_∞(T) = (9.5 ± 1.2) × (10^-11) × (T/298 K)^(-1.33 ± 0.32) cm^3 molecule^-1 s^-1) and the abstraction channel, (k_abstraction_∞(T) = (1.3 ± 0.3) × (10^-11) × exp((-3.61 kJ mol^-1)/RT) cm^3 molecule^-1 s^-1). With respect to the OH addition, a comparison with previous investigations suggests that only our measurements at T > 700 K were in the fall-off region, contradicting some literature studies. A new method of analysis via a global multi-temperature, multi-pressure fitting procedure was developed and used for the study of the ethylene + OH reaction. The method relied on the Master Equation modelling of the OH addition, and a subsequent incorporation of new consumption and formation terms to the rate laws of the involved species. With effect, the simulated traces become comparable to experimental observations and a direct trace analysis is possible. The reaction of OH with ethylene was studied over a range of temperatures (563 - 723 K) and pressures (~60 220 Torr), which included pressure dependent data, to test the limits of this global direct trace analysis. Excellent descriptions of OH traces were obtained when the Master Equations were modified to incorporate a hydrogen abstraction and a unimolecular loss of the adduct. A simultaneous fit of 96 traces where direct ethylene + OH ⇄ adduct equilibration was observed enabled the determination of the well-depth of the adduct (111.8 ± 0.20 kJ mol^-1). This value is in excellent agreement with our theoretical prediction (111.4 kJ mol^-1), calculated at the CCSD(T)/CBS//M06-2X/ aug cc pVTZ level of theory. The high pressure limiting rate coefficient for the OH addition extracted from the experimental traces by this technique (k_addition_∞(T)=(8.13 ± 0.86) × (10^-12) × (T/298 K)^(-0.99 ± 0.18) cm^3 molecule^-1 s^-1), is in very good agreement with the IUPAC recommendation for the 100 - 500 K temperature range (k_1a_∞(T)= 9 × (10^-12) × (T/300 K)^-0.85 cm^3 molecule^-1 s^-1). Furthermore, the experimentally derived abstraction rate coefficients k_abstraction(T) = (3.5 ± 0.75) × (10^-11) × exp((-26.2 ± 1.3 kJ mol^-1)/RT) cm^3 molecule^-1 s^-1 are in excellent agreement with previous investigations. The method proved to be robust enough to discriminate and quantify the competing processes influencing the shapes of the experimental OH profiles. This novel analysis was employed for the study of LIM1, a promising mechanism for the description of OH recycling via isoprene peroxy chemistry. Experiments were undertaken at elevated temperatures (400 < T < 600 K) and large concentrations of O2 were employed ([O2]~10^17 molecules cm^-3) so as to promote the recycling to the millisecond timescale, compatible with direct experimental techniques for OH detection. Rate coefficients measured in the absence of O2 were incorporated to help constrain the analysis of the data. The LIM1 mechanism proved to be capable of accurately describing non-exponential traces collected under such experimental conditions. The OH recycling involves crucial hydrogen shifts, whose barriers were adjusted in unison to provide a good fit to the data. However, very small modifications were necessary for this purpose (~ 2 kJ mol^-1). The incorporation of these findings in an atmospheric model enabled the description of approximately 50% of the OH concentration measured in a field campaign performed in a Borneo rainforest, an environment dominated by biogenic volatile organic compounds emissions. Finally, the thesis concludes in Chapter 7 with a summary of the results of each experimental chapter including suggestions for further areas of study.
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- 2019
3. Intensity matters: protocol for a randomized controlled trial exercise intervention for individuals with chronic stroke
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Rodrigues, Lynden, Moncion, Kevin, Eng, Janice J., Noguchi, Kenneth S., Wiley, Elise, de Las Heras, Bernat, Sweet, Shane N., Fung, Joyce, MacKay-Lyons, Marilyn, Nelson, Aimee J., Medeiros, Diogo, Crozier, Jennifer, Thiel, Alexander, Tang, Ada, and Roig, Marc
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- 2022
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4. Transtorno de ansiedade generalizada: revisão de literatura
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Fagundes, Amanda Martins, primary, Moura, Aline Machado de, additional, Rosário, Carolina Cassiano do, additional, Miranda, Pavleska Bartos, additional, Souza, Thais Heloan de, additional, Silva, Thamires Barbara Cardoso da, additional, Moreira, Anna Karla Lorrane Guimarães, additional, Kachani, Julia, additional, Medeiros, Diogo Aquino Pacheco de, additional, Bonfim, Daniel José Pimentel, additional, Queiroz, Thearley Marques de, additional, Avelar, Luiza Magalhães, additional, Souza, Valmari Felix de, additional, Moura, Marcelo da Silva, additional, Sousa, Anny Karoline Cardoso de, additional, Rodrigues, Anna Angelica de Oliveira, additional, Silva, Jennifer Favaretti, additional, Pereira, Melina Kimberly Carvalho, additional, Lourenço, Isabella de Oliveira, additional, and Sellenave Filho, Mário Antônio, additional
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- 2024
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5. Cost analysis of photobiomodulation in tibia fracture in the Brazilian public health system
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Jana Neto, Frederico Carlos, primary, Martimbianco, Ana Luiza Cabrera, additional, de Medeiros, Diogo Valvano, additional, Felix, Fernanda Carolina, additional, Mesquita-Ferrari, Raquel Agnelli, additional, Bussadori, Sandra Kalil, additional, Duran, Cinthya Cosme Gutierrez, additional, Motta, Lara Jansiski, additional, Barbosa, Estela Capelas, additional, and Fernandes, Kristianne Porta Santos, additional
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- 2023
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6. Produção capitalista e habitação: Novos produtos imobiliários no espaço urbano da região administrativa norte de Natal-RN
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Carvalho, Élida Thalita Silva de, primary, Oliveira, Júlia Diniz de, additional, Santos, Wanderson Benigno dos, additional, Medeiros, Diogo Bernardino Santos de, additional, Amorim, João Paulo de Almeida, additional, and Santos, Alex de Lima, additional
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- 2020
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7. A mão visível do estado na urbanização da cidade do Natal/RN (Século XX): Primeiras aproximações
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Medeiros, Diogo Bernardino Santos de, primary, Santos, Alex de Lima, additional, Gonçalo, Tiago Ananias, additional, Amorim, João Paulo de Almeida, additional, Carvalho, Élida Thalita Silva de, additional, and Oliveira, Júlia Diniz de, additional
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- 2020
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8. Violência no trânsito envolvendo motociclistas e os seus desdobramentos sociais no espaço urbano
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Oliveira, Júlia Diniz de, primary, Carvalho, Élida Thalita Silva de, additional, Dantas, Denis Rodrigues, additional, Amorim, João Paulo de Almeida, additional, Santos, Alex de Lima, additional, and Medeiros, Diogo Bernardino Santos de, additional
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- 2020
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9. A região metropolitana de Macapá: Entre o institucional e o espacial
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Amorim, João Paulo de Almeida, primary, Oliveira, Júlia Diniz de, additional, Santos, Alex de Lima, additional, Medeiros, Diogo Bernardino Santos de, additional, and Carvalho, Élida Thalita Silva de, additional
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- 2020
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10. Da Centralidade Simbólica a Centralidade Socioterritorial de Macapá na Amazônia Setentrional Amapaense
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Santos, Alex de Lima, primary, Amorim, João Paulo de Almeida, additional, Oliveira, Júlia Diniz de, additional, Carvalho, Élida Thalita Silva de, additional, and Medeiros, Diogo Bernardino Santos de, additional
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- 2020
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11. The effects of aging on cortico-spinal excitability and motor memory consolidation
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Centeno, Carla, Medeiros, Diogo, Beck, Mikkel Malling, Lugassy, Liav, Gonzalez, David Fernandez, Nepveu, Jean Francois, and Roig, Marc
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- 2018
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12. New Measurements and Calculations on the Kinetics of an Old Reaction: OH + HO2 → H2O + O2
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Speak, Thomas H., primary, Blitz, Mark A., additional, Medeiros, Diogo J., additional, and Seakins, Paul W., additional
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- 2023
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13. Técnicas e complicações da abdominoplastia: Revisão de literatura
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Fagundes, Amanda Martins, primary, Lopes, Rebeca Bulhões, additional, Kachani, Julia, additional, Medeiros, Diogo Aquino Pacheco de, additional, Andrade, Luana Nunes de Morais, additional, Chiacchio, Gabriel Machado, additional, Casale, Rafaella Regina Albero, additional, Silva, Nathalia Fernandes Correia, additional, Lima, Maria Eduarda Vasconcelos de, additional, Rosário, Carolina Cassiano do, additional, Costa, Deborah Figueiredo, additional, Ferreira Junior, Jovani Gomes, additional, Barbosa, Analice Silva Henrique, additional, Santos, Larissa Stefani, additional, and Castiblanco, Jessica Lorena Hoyos, additional
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- 2023
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14. Melanoma with osteocartilaginous differentiation
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Barroso de Carvalho, Bennett, primary and Batista dos Santos Medeiros, Diogo, additional
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- 2023
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15. Forest Fire Agent-Based Modelling
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Medeiros, Diogo and Santos, João
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- 2023
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16. Icon Generation with Conditional Generative Adversarial Networks
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Medeiros, Diogo
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- 2023
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17. CERRADO ENCLAVE AND THE UPDATE OF THE MAPPING OF LANDSCAPE UNITS IN THE STATE OF RIO GRANDE DO NORTE
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Diniz, Marco Túlio Mendonça, primary, Souza, Ana Caroline Damasceno, additional, Medeiros, Diogo Bernardino Santos de, additional, Oliveira, Antônia Vilaneide Lopes Costa de, additional, and Silva, Sandro Damião Ribeiro da, additional
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- 2022
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18. Improved calibration procedures for the EM27/SUN spectrometers of the COllaborative Carbon Column Observing Network (COCCON)
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Alberti, Carlos, Hase, Frank, Frey, Matthias, Dubravica, Darko, Blumenstock, Thomas, Dehn, Angelika, Castracane, Paolo, Surawicz, Gregor, Harig, Roland, Baier, Bianca, Bès, Caroline, Bi, Jianrong, Boesch, Hartmut, Butz, André, Cai, Zhaonan, Chen, Jia, Crowell, Sean, Deutscher, Nicholas, Ene, Dragos, Franklin, Jonathan, García, Omaira, Griffith, David, Grouiez, Bruno, Grutter, Michel, Hamdouni, Abdelhamid, Houweling, Sander, Humpage, Neil, Jacobs, Nicole, Jeong, Sujong, Joly, Lilian, Jones, Nicholas, Jouglet, Denis, Kivi, Rigel, Kleinschek, Ralph, Lopez, Morgan, Medeiros, Diogo, Morino, Isamu, Mostafavipak, Nasrin, Müller, Astrid, Ohyama, Hirofumi, Palmer, Paul, Pathakoti, Mahesh, Pollard, David, Raffalski, Uwe, Ramonet, Michel, Ramsay, Robbie, Sha, Mahesh Kumar, Shiomi, Kei, Simpson, William, Stremme, Wolfgang, Sun, Youwen, Tanimoto, Hiroshi, Té, Yao, Tsidu, Gizaw Mengistu, Velazco, Voltaire, Vogel, Felix, Watanabe, Masataka, Wei, Chong, Wunch, Debra, Yamasoe, Marcia, Zhang, Lu, Orphal, Johannes, Sha, Mahesh, Tsidu, Gizaw, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ICOS-RAMCES (ICOS-RAMCES), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique et Atmosphères = Laboratory for Studies of Radiation and Matter in Astrophysics and Atmospheres (LERMA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)
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[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment - Abstract
International audience; Abstract. In this study, an extension on the previously reported status of the COllaborative Carbon Column Observing Network's (COCCON) calibration procedures incorporating refined methods is presented. COCCON is a global network of portable Bruker EM27/SUN FTIR spectrometers for deriving column-averaged atmospheric abundances of greenhouse gases. The original laboratory open-path lamp measurements for deriving the instrumental line shape (ILS) of the spectrometer from water vapour lines have been refined and extended to the secondary detector channel incorporated in the EM27/SUN spectrometer for detection of carbon monoxide (CO). The refinements encompass improved spectroscopic line lists for the relevant water lines and a revision of the laboratory pressure measurements used for the analysis of the spectra. The new results are found to be in good agreement with those reported by Frey et al. (2019) and discussed in detail. In addition, a new calibration cell for ILS measurements was designed, constructed and put into service. Spectrometers calibrated since January 2020 were tested using both methods for ILS characterization, open-path (OP) and cell measurements. We demonstrate that both methods can detect the small variations in ILS characteristics between different spectrometers, but the results of the cell method indicate a systematic bias of the OP method. Finally, a revision and extension of the COCCON network instrument-to-instrument calibration factors for XCO2, XCO and XCH4 is presented, incorporating 47 new spectrometers (of 83 in total by now). This calibration is based on the reference EM27/SUN spectrometer operated by the Karlsruhe Institute of Technology (KIT) and spectra collected by the collocated TCCON station Karlsruhe. Variations in the instrumental characteristics of the reference EM27/SUN from 2014 to 2017 were detected, probably arising from realignment and the dual-channel upgrade performed in early 2018. These variations are considered in the evaluation of the instrument-specific calibration factors in order to keep all tabulated calibration results consistent.
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- 2022
19. Direct Measurements of Isoprene Autoxidation: Pinpointing Atmospheric Oxidation in Tropical Forests
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J. Medeiros, Diogo, primary, Blitz, Mark A., additional, Seakins, Paul W., additional, and Whalley, Lisa K., additional
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- 2022
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20. CERRADO ENCLAVE AND THE UPDATE OF THE MAPPING OF LANDSCAPE UNITS IN THE STATE OF RIO GRANDE DO NORTE
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Diniz, Marco Túlio Mendonça, Souza, Ana Caroline Damasceno, Medeiros, Diogo Bernardino Santos de, Oliveira, Antônia Vilaneide Lopes Costa de, and Silva, Sandro Damião Ribeiro da
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Análisis del Paisaje ,Geosystem ,Geossistema ,Geoprocessing Techniques ,Técnicas de Geoprocesamiento ,Análise da Paisagem ,Geosistema ,Técnicas de Geoprocessamento ,Landscape Analysis - Abstract
Resumo O mapeamento de unidades de paisagem é um processo dinâmico e necessitado de constantes modificações. Partindo dessa premissa, este artigo buscou atualizar o mapeamento de unidades de paisagens do estado do Rio Grande do Norte. Isso foi possível a partir da combinação entre atividades de campo e novos procedimentos metodológicos, com análises e refinamentos de mapeamentos anteriores efetuados por Silva (2018), Bernardino (2019) e Souza (2020). Como principal resultado apresenta-se a atualização de um mapeamento que contempla a (re-)delimitação e (re-)classificação dos Domínios Morfoclimáticos, Regiões Naturais e Geocomplexos do território do estado do Rio Grande do Norte. Foi identificada e inserida uma nova unidade: um enclave de cerrado, que, até então, não havia sido descrito e analisado como tal na literatura consagrada; a reboque, mais uma região natural e dois geocomplexos puderam ser mapeados e delimitados. Mapeou-se, também, novas ocorrências territoriais de unidades já identificadas/classificadas no trabalho original e, por conseguinte, ocorreu um redimensionamento de paisagens de diferentes táxons, também como resultado, propriamente, dessas modificações, bem como do refinamento dos limites das unidades, em função do detalhamento escalar maior, com o aprofundamento da pesquisa. Resumen El mapeo de unidades de paisaje es un proceso dinámico y necesita modificaciones constantes. Con base en esta premisa, este artículo buscó actualizar el mapeo de unidades de paisaje en el estado de Rio Grande do Norte. Esto fue posible a través de la combinación de actividades de campo y nuevos procedimientos metodológicos, con análisis y refinamientos de mapeos previos realizados por Silva (2018), Bernardino (2019) y Souza (2020). El principal resultado es la actualización de un mapeo que contempla la (re) delimitación y (re) clasificación de Dominios Morfoclimáticos, Regiones Naturales y Geocomplejos en el estado de Rio Grande do Norte. Se identificó e insertó una nueva unidad: un enclave cerrado, que hasta entonces no había sido descrito y analizado como tal en la literatura consagrada; a continuación, se podría cartografiar y delimitar otra región natural y dos geocomplejos. También se mapearon nuevas ocurrencias territoriales de unidades ya identificadas / clasificadas en el trabajo original y, por lo tanto, hubo un redimensionamiento de paisajes de diferentes taxones, también como resultado, propiamente, de estas modificaciones, así como del refinamiento de los límites de las unidades, debido al mayor detalle escalar, con la profundización de la investigación. Abstract The mapping of landscape units is a dynamic process in which constant modifications are needed. Based on this, this article sought to update the mapping of landscape units in the state of Rio Grande do Norte. This was possible due to the combination of field activities and new methodological procedures, with analyzes and refinements of previous mappings conducted by Silva (2018), Bernardino (2019), and Souza (2020). The main result is the update of a mapping that includes the (re-) delimitation and (re-) classification of Morphoclimatic Domains, Natural Regions, and Geocomplexes in the territory of this state. A new unit was identified and inserted: a cerrado enclave, which, until then, had not been described and analyzed as such in the established literature; consequently, one more natural region and two geocomplexes were mapped and delimited. New territorial occurrences of units already identified/classified in the original work were also mapped and, therefore, there was a resizing of landscapes of different taxa, which resulted from these modifications and of the refinement of their limits, due to the greater scalar detail, with the deepening of the research.
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- 2022
21. Deep Learning Attention Models for Hyperspectral Image Analysis
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Medeiros, Diogo and Melo-Pinto, Pedro
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- 2022
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22. Additional file 1 of Intensity matters: protocol for a randomized controlled trial exercise intervention for individuals with chronic stroke
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Rodrigues, Lynden, Moncion, Kevin, Eng, Janice J., Noguchi, Kenneth S., Wiley, Elise, de Las Heras, Bernat, Sweet, Shane N., Fung, Joyce, MacKay-Lyons, Marilyn, Nelson, Aimee J., Medeiros, Diogo, Crozier, Jennifer, Thiel, Alexander, Tang, Ada, and Roig, Marc
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Additional file 1. Populated SPIRIT Checklist.
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- 2022
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23. New Measurements and Calculations on the Kinetics of an Old Reaction: OH + HO2→ H2O + O2
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Speak, Thomas H., Blitz, Mark A., Medeiros, Diogo J., and Seakins, Paul W.
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Literature rate coefficients for the prototypical radical–radical reaction OH+HO2→k1H2O+O2at 298 K vary by close to an order of magnitude; such variations challenge our understanding of fundamental reaction kinetics. We have studied the title reaction at room temperature via the use of laser flash photolysis to generate OH and HO2radicals, monitoring OH by laser-induced fluorescence using two different approaches, looking at the direct reaction and also the perturbation of the slow OH + H2O2reaction with radical concentration, and over a wide range of pressures. Both approaches give a consistent measurement of k1,298K∼1 × 10–11cm3molecule–1s–1, at the lowest limit of previous determinations. We observe, experimentally, for the first time, a significant enhancement in the rate coefficient in the presence of water, k1,H2O, 298K= (2.17 ± 0.09) × 10–28cm6molecule–2s–1, where the error is statistical at the 1σ level. This result is consistent with previous theoretical calculations, and the effect goes some way to explaining some, but not all, of the variation in previous determinations of k1,298K. Supporting master equation calculations, using calculated potential energy surfaces at the RCCSD(T)-F12b/CBS//RCCSD/aug-cc-pVTZ and UCCSD(T)/CBS//UCCSD/aug-cc-pVTZ levels, are in agreement with our experimental observations. However, realistic variations in barrier heights and transition state frequencies give a wide range of calculated rate coefficients showing that the current precision and accuracy of calculations are insufficient to resolve the experimental discrepancies. The lower value of k1,298Kis consistent with experimental observations of the rate coefficient of the related reaction, Cl + HO2→ HCl + O2. The implications of these results in atmospheric models are discussed.
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- 2023
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24. CONDICIONANTES NATURAIS E DISTRIBUIÇÃO ESPACIAL DAS ECONOMIAS FUNDANTES DO RIO GRANDE DO NORTE: SUCROCULTURA E PECUÁRIA NOS SÉCULOS XVII E XVIII
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Mendonça Diniz, Marco Túlio, Santos De Medeiros, Diogo Bernardino, and De Oliveira, George Pereira
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Ciclos Econômicos ,Formação Territorial ,Nordeste do Brasil ,Clima ,Relação Sociedade-Natureza - Abstract
O território colonial brasileiro teve sua formação alicerçada pela exploração econômica do meio natural. Ao perceber-se que há uma ligação direta entre as práticas econômicas e as condições físicas do espaço natural, objetivou-se com essa pesquisa compreender e demonstrar a influência dos condicionantes naturais no desenvolvimento das atividades econômicas fundantes do território do estado do Rio Grande do Norte. Neste trabalho, deu-se ênfase aos dois primeiros ciclos econômicos que motivaram a ocupação deste território, ou seja, agricultura de cana-de-açúcar e pecuária bovina. Assim, foi realizada uma revisão da literatura existente acerca desses ciclos econômicos e suas consequências na produção territorial. Logo após se buscou entender os condicionantes naturais da área, especialmente a climatologia do estado. Por fim, ao comparar a aptidão climática, através dos resultados do Balanço Hídrico, das regiões mais produtivas de cana-de-açúcar com a de Natal, concluiu-se que a Capitania do Rio Grande apresentava condições naturais insuficientes ao desenvolvimento da sucrocultura em baixo nível técnico, ao contrário das outras capitanias do Nordeste Oriental, sendo esse o motivo principal que ocasionou sua tardia ocupação. Nessas circunstâncias, ocorreu o surgimento de uma outra atividade econômica que se desenvolveu inicialmente subsidiária a essa. A pecuária obteve grande progresso no interior do estado, de clima semiárido, já que essa região apresentava uma distância apropriada em relação ao litoral (zona canavieira) e amplas áreas com vegetação esparsa, que propiciavam sua execução extensiva próxima a canais de drenagem.
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- 2021
25. OH Kinetics with a Range of Nitrogen-Containing Compounds: N-Methylformamide, t-Butylamine, and N-Methyl-propane Diamine
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Speak, Thomas H., primary, Medeiros, Diogo J., additional, Blitz, Mark A., additional, and Seakins, Paul W., additional
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- 2021
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26. Jogos Olímpicos Tóquio 2020: uma análise correlata com a pandemia da COVID-19 e a vacinação.
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Santos, Thaina Pereira dos, primary, Terra, Ana Paula Macedo, additional, and Medeiros, Diogo, additional
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- 2021
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27. Evaluation of the Effect of Acute Sibutramine in Female Rats in the Elevated T-Maze and Elevated Plus-Maze Tests
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Santos, Raliny O., de Assunção, Gabriela L. M., de Medeiros, Diogo M. B., de Sousa Pinto, Ícaro A., de Barros, Keizianny S., Soares, Bruno L., André, Eunice, Gavioli, Elaine C., and de Paula Soares-Rachetti, Vanessa
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- 2014
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28. MAPEO Y ANÁLISIS MORFOSTRUCTURAL DE LA MACIZO JOÍO DO VALE (RN-PB)
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Oliveira, George Pereira de, Medeiros, Diogo Bernardino Santos de, and Teixeira Batista, Clístenes
- Abstract
In the Borborema Province, several massifs covered by cenozoic sandstones raised to elevations of about 750 m are indicated as indicators of neotectonic activity. Among these massifs, the Serra do João do Vale remains the most devoid of studies. The study of structural lines in the area is important for the identification of clues about the current morphostructural picture of Serra de João de Vale inherited from cenozoic tectonic movements. Knowing this, the objective of this work was to present a preliminary morphostructural mapping for the referred massif, based on the surface relationships between the structural lineaments, the predominant lithotypes and the local topographic amplitudes. To achieve this, remote sensing techniques were used. The occurrence of seven morphostructural compartments was identified. It is hoped that this work will be the initial step for future work in the region that is more in-depth. En la Provincia de Borborema, varios macizos cubiertos por areniscas cenozoicas elevadas a elevaciones de aproximadamente 750 m están indicados como indicadores de actividad neotectónica. Entre estos macizos, la Serra do João do Vale sigue siendo la más desprovista de estudios. El estudio de las líneas estructurales en el área es importante para la identificación de pistas sobre la imagen morfoestructural actual de la Serra de João de Vale heredada de los movimientos tectónicos cenozoicos. Sabiendo esto, el objetivo de este trabajo fue presentar un mapeo morfoestructural preliminar para el macizo referido, basado en las relaciones superficiales entre los lineamientos estructurales, los litotipos predominantes y las amplitudes topográficas locales. Para lograr esto, se utilizaron técnicas de teledetección. Se identificó la aparición de siete compartimentos morfoestructurales. Se espera que este trabajo sea el paso inicial para el trabajo futuro en la región que es más profundo. Na Província Borborema, diversos maciços capeados por arenitos cenozoicos alçados a cotas de cerca de 750 m de altitude são apontados como indicadores de atividade neotectônica. Dentre esses maciços, a Serra de João do Vale permanece como o mais desprovido de estudos. O estudo dos lineamentos estruturais na área é importante para a identificação de pistas sobre o atual quadro morfoestrutural da Serra de João de Vale herdado de movimentações tectônicas cenozoicas. Sabendo-se disso, objetivou-se neste trabalho apresentar um mapeamento morfoestrutural preliminar para o referido maciço, baseado nas relações em superfície entre os lineamentos estruturais, os litotipos predominantes e as amplitudes topográficas relativas locais. Para conseguir isso se fez uso de técnicas de sensoriamento remoto. Identificou-se a ocorrência de sete compartimentos morfoestruturais. Espera-se que este trabalho seja o passo inicial para futuros trabalhos na região mais aprofundados no quadro.
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- 2020
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29. A disease disregards anatomical planes: actinomycosis and an intrauterine device
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Gilbert, Lucy, primary, Miller, Kyle, additional, Medeiros, Diogo, additional, Tsatoumas, Maria, additional, Ciarallo, Anthony, additional, Isabwe, Ghislaine, additional, Malek, Joelle, additional, Loo, Vivian G, additional, and Kumar, Princy N, additional
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- 2020
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30. As Brincadeiras Realizadas por Crianças nas Praças da Cidade de Patos-PB
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Bezerra, Alana Simões, primary and Medeiros, Diogo Peixoto, additional
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- 2020
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31. Avaliação da estrutura florística associada aos riscos de desligamentos ao longo de uma linha de transmissão de energia elétrica, localizada no estado do Rio Grande do Sul, Brasil
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Duarte, Samara Welter, primary, Blunk, Leandro, additional, Maçaneiro, João Paulo, additional, Fenilli, Tatiele Anete Bergamo, additional, Refosco, Julio Cesar, additional, Marcolin, Moacir, additional, and Medeiros, Diogo Soliman, additional
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- 2020
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32. Mapeamento e análise integrada das unidades de paisagem (geofácies) do Seridó Potiguar
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Medeiros, Diogo Bernardino Santos de, Costa, Diogenes Felix da Silva, Vital, Saulo Roberto de Oliveira, Albuquerque, Emanuel Lindemberg Silva, and Diniz, Marco Túlio Mendonça
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Análise integrada da paisagem ,Mapeamento de Geofácies ,Seridó potiguar ,CIENCIAS HUMANAS::GEOGRAFIA [CNPQ] - Abstract
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) A cadeia dos acontecimentos naturais e antrópicos imprimiram uma paisagem díspar no seio do Semiárido Brasileiro: o Seridó Potiguar. A região se apresenta destacada de suas adjacências pelas particularidades físico-naturais e socioculturais que se manifestam tridimencionalmente indissociadas em sua superfície. Para além disso, o que se nos parece uniforme/homogêneo, quando aguçadas as observações e a escala de abordagem, deslinda-se como um verdadeiro mosaico paisagístico complexo, cujas estrutura e dinâmica, considerando cada geofácie componente, traduzem fielmente os detalhes desse chão e povo. Compartimentar essas unidades de paisagem (geofácies) e realizar uma análise integrada multiescalar (da zona climática às fácies fisionômicas) de suas dinâmicas socioambientais constituíram o fito deste trabalho. Antes, porém, implicou-se conhecer profundamente a epistemologia geográfica capaz de fornecer a óptica adequada para tal. A teoria geossistêmica, do geógrafo francês Georges Bertrand, serviu-nos, justamente, como esse prisma teórico-metodológico, permitindo-nos perceber/analisar sistemicamente a paisagem, sobretudo a partir do geofácie (abstração), um setor fisionomicamente homogêneo na superfície, segundo seu sistema taxonômico. As categorias de análise “Dinâmica Temporal e Espacial da Paisagem”, “Tipologia Ecodinâmica da Paisagem” e “Cartografia das Paisagens”, preconizadas em tal concepção teóricometodológica, foram tomadas para este estudo com as adaptações reputadas necessárias, baseando-se em trabalhos que já se empenharam em discuti-las e aplicá-las. As técnicas e procedimentos empreendidos nesta pesquisa são referentes, principalmente, à modelagem cartográfica em ambiente virtual de Sistemas de Informações Geográficas. Em suma, partindose de contribuições cartográficas antecedentes para táxons superiores no Rio Grande do Norte (domínio, região natural, geocomplexo), realizou-se a vetorização manual, por fotointerpretação/teledetecção, das quebras de paisagem, na escala de 1:50.000, em imagens orbitais Sentinel-2, com resolução espacial de 10 metros e composição colorida real R04G03B02. Isso se deu a partir da construção de fichas de interpretação indutiva, que permitiram, a partir da determinação de poucos casos (geofácies) e suas validações em campo (com auxílio de ficha de campo), atribuir uma generalização para compartimentos de mesma fisionomia. Os dados obtidos possibilitaram elaborar um modelo cartográfico que apontou para a existência de 30 (trinta) diferentes geofácies no Seridó Potiguar, os quais tiveram sua dinâmica e elementos distintivamente paisagísticos sintetizados (análise sistêmica), em texto, com base na articulação de conhecimentos empíricos e de literatura temática. Por fim, os resultados foram avaliados qualiquantitativamente, em termos de extensão espacial, absoluta e relativa, de modo que foi possível empreender complementos e maior robustez às hipóteses de fisionomia e fisiologia das unidades identificadas, estabelecendo uma espécie de diagnóstico panorâmico de situação espacial, temporal e ecodinâmica das paisagens seridoenses. Destarte, reputa-se que a metodologia empregada permitiu avançar nos conhecimentos geossistêmicos do Seridó, em relação a trabalhos anteriores, ao passo que se expecta que essas contribuições atinjam, minimamente, o fim último de tornar, pelas vias virtuosas da ciência, a vida sertaneja gradualmente mais congruente com o seu meio, mormente, no sertão seridoense. The chain of natural and anthropic events impressed a disparate landscape within the Brazilian Semiarid: the Seridó Potiguar. The region is detached from its surroundings by the physicalnatural and socio-cultural particularities that manifest themselves three-dimensionally inseparable on its surface. Furthermore, what seems to us to be uniform/homogeneous, when the observations and scale of approach are sharpened, moves like a true complex paisagistic mosaic, whose structure and dynamics, considering each component geofacies, faithfully reflects the details of this land and people. Mapping these landscape units (geofacies) and performing an integrated multiscale analysis (from climate zone to physiognomic facies) of their socioenvironmental dynamics established the purpose of this work. But before that, it was necessary to know deeply the geographical epistemology capable to provide the appropriate optics for this. The geosystemic theory, by the French geographer Georges Bertrand, served us precisely as this theoretical-methodological prism, which allowed us to perceive/analyze the landscape systemically, mainly from geofacies (abstraction), a physiognomically homogeneous sector on the surface, according to its taxonomic system. The categories of analysis “Temporal and Spatial Landscape Dynamics”, “Ecodynamic Landscape Typology” and “Landscape Cartography”, advocated in such theoretical and methodological conception, were taken for this study with the necessary reputed adaptations, based on works which have already endeavored to discuss and apply them. The techniques and procedures involved in this research refer mainly to cartographic modeling in a virtual environment of Geographic Information Systems. In sum, starting from previous cartographic contributions for superior higher taxa in Rio Grande do Norte (domain, natural region, geocomplex), we performed the manual vectorization, by photointerpretation/teledetection, of landscape breaks, in the scale 1:50.000, in Sentinel-2 orbital images with spatial resolution of 10 meters and real color composition R04G03B02. This was due to the construction of inductive interpretation files, which allowed, from the determination of a few cases (geofacies) and their validation in the field (with the help of the field files), to assign a generalization to compartments of the same physiognomy. The obtained data allowed to elaborate a cartographic model that pointed to the existence of 30 different geofacies in Seridó Potiguar, which had their dynamics and distinctively landscape elements synthesized (systemic analysis), in text, based on the articulation of empirical data and thematic literature. Finally, the results were qualitatively and qualitatively evaluated, in terms of spatial, absolute and relative extent, so that it was possible to undertake complements and greater robustness to the hypotheses of physiognomy and physiology of the seridoense landscapes, establishing a certain panoramic diagnosis of spatial and temporal situation and ecodynamics of these units. Thus, it is considered that the employed methodology allowed to advance in the geosystemic knowledge of the seridoense landscape, regarding to previous works, whereas these contributions are expected to minimally achieve the ultimate goal of making, through the virtuous pathways of science, country life gradually more congruent with its surroundings, especially in the seridoense hinterland.
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- 2019
33. Georges Bertrand e a Análise Integrada da Paisagem em Geografia
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Bernardino Santos de Medeiros, Diogo, Oliveira, Alisson Medeiros de, and Diniz, Marco Túlio Mendonça
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No sentido de colaborar com o conhecimento sobre a análise da paisagem em Geografia, propõe-se, aqui, um artigo de revisão bibliográfica que trate, de maneira crítica e analítica, das contribuições teórico-metodológicas de Georges Bertrand para essa temática. Esse autor, em 1968, no contexto de renovação da Geografia e de desenvolvimento progressivo de sínteses naturalistas mais rebuscadas, concebeu a Análise Integrada da Paisagem (Paisagem e Geografia Física Global; Teoria Geossistêmica Bertrandiana) – amplamente difundida na Geografia brasileira. No presente trabalho, busca-se abordar o contexto histórico-científico dessa teoria, os seus conceitos-chave, sua singularidade perante sínteses naturalistas similares, a metodologia proposta e as principais críticas e proposições a ela direcionadas. Expecta-se que o referido trabalho – de cunho panorâmico – favoreça a inserção dessas concepções nas novas gerações acadêmicas de Geografia.
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- 2018
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34. Narrativas jornalísticas para o povo surdo
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Medeiros, Diogo de Souza, primary, Falavina, Iraci Helena de Oliveira, additional, and Baldessar, Maria José, additional
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- 2018
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35. Gas-phase rate coefficients for a series of alkyl cyclohexanes with OH radicals and Cl atoms
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Bejan, Iustinian G., primary, Winiberg, Frank A. F., additional, Mortimer, Nicholas, additional, Medeiros, Diogo J., additional, Brumby, Charlotte A., additional, Orr, Stephanie C., additional, Kelly, Jamie, additional, and Seakins, Paul W., additional
- Published
- 2018
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36. Unimolecular decomposition kinetics of the stabilised Criegee intermediates CH2OO and CD2OO
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Stone, Daniel, primary, Au, Kendrew, additional, Sime, Samantha, additional, Medeiros, Diogo J., additional, Blitz, Mark, additional, Seakins, Paul W., additional, Decker, Zachary, additional, and Sheps, Leonid, additional
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- 2018
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37. Experimentally Determined Site-Specific Reactivity of the Gas-Phase OH and Cl + i-Butanol Reactions Between 251 and 340 K
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McGillen, Max R., primary, Tyndall, Geoffrey S., additional, Orlando, John J., additional, Pimentel, Andre S., additional, Medeiros, Diogo J., additional, and Burkholder, James B., additional
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- 2016
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38. Análise dinâmica do remate do futebol: influência da curva força-velocidade dos músculos extensores e flexores do joelho
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Medeiros, Diogo Bernardo and Faro, Ana
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Joelho ,Futebol ,Músculos - Abstract
Dissertação de mestrado em Biocinética, apresentada à Faculdade de Ciências do Desporto e Educação Física da Universidade de Coimbra O presente trabalho teve como principal objetivo determinar a influência dos valores da curva força-velocidade dos flexores e extensores do joelho no remate de futebol. Foram avaliados sete atletas amadores de futebol (25,1 ± 1,97 anos), os quais foram submetidos a dois tipos de testes. Sendo o primeiro cinemático, através da filmagem de execução de um remate de futebol. Posteriomente, foi feita uma análise no programa kinovea, para determinar a velocidade de saida de bola, variáveis temporais e comportamento angular. Para a recolha dos dados isocinéticos foi utilizado um dinamómetro (Biodex Multijoint System 3 Pro 2) para cálculo da força máxima do membro inferior dos sujeitos. Na análise cinemática do futebol a variável velocidade máxima do joelho foi a que obteve maior correlação com a velocidade de saída de bola (r=0.96; P≤0.001). As variáveis, Distância do pé à bola e a Percentagem da posição do centro de gravidade obtiveram valores de correlação significativos (r=0.81 e r= 0.83; P≤ 0.01) correspondentemente. Por fim, as variáveis, ângulo da cintura pélvica e deslocamento angular do joelho em extensão, também mostraram correlações significativas (r=0.76 e r=0.70; P≤0.05) com a velocidade de saída de bola. Na correlação entre variáveis cinemáticas do remate de futebol com os testes isocinéticos, constatou-se que das três variáveis analisadas, os resultados das diferenças dos valores dos torques máximos em todas as velocidades de teste e o valor dos ângulos nos torques máximos obtiveram maior número de correlações significativas (ambas com 12 correlações cada para P≤0.05), já os valores dos torques máximos apenas obtiveram quatro correlações significativas para P≤0.05. Concluindo, a variável cinemática mais importante para o remate de futebol é a velocidade máxima do joelho, sendo que só é possível a sua análise a partir da utilização de novas tecnologias no treino. Relativamente aos testes isocinéticos, verificamos que a aplicação da curva força-velocidade nos testes isocinéticos apresenta mais informações do que os valores dos torques máximos. Palavras-chave: Futebol; Análise Cinemática; Testes Isocinéticos; Curva Força-Velocidade. iv Abstract The purpose of this study was to establish the values which influence the force-velocity curve of flexors and knee extensors on the soccer kick. Our subjects were seven amateur soccer players (25.1 ± 1.97 years), who underwent two types of tests. Therefore, the first Kinematic test was the avaluation of the soccer kick and maximal instep kicking with the preferred leg. Afterwards, an analysis on Kinovea program was made in order to calculate the ball speed, the angular behavior, and temporal variables. For the collection of data we used isokinetic dynamometers ((Biodex System 3 Pro Multijoint 2) to calculate the maximum strength of the lower member of the subjects. In kinematics football analysis, the variable maximum knee speed, was the one with the highest correlation with the ball speed (r = 0.96; P≤0.001). The variables, distance from the ball to the foot and the percentage of the center of gravity position obtained significant correlation (r = 0.81 and r = 0.83; P ≤ 0.01) correspondingly. Finally, the variables angle of the pelvis and the knee angular movement in extension, also showed a significant correlation (r = 0.76 and r = 0.70; P≤0.05) with the ball speed. As far as the correlation between kinematic variables football kicking with the isokinetic testing is concerned, it was found that the three variables in study, which were the results of the differences of the values of the maximum torque in all test speed and the value of the angles the maximum torques obtained more significant correlations (both with 12 correlations for each P≤0.05), since the values of the maximum torques only had four significant correlations for p≤0.05. In conclusion, the most important kinematics variable for the football kick is the maximum speed of the knee, and it is only possible to analyse by using new technologies in training. For isokinetic tests, we found that the application of the force-velocity curve in isokinetic tests gave us more information than the values of the maximum torques
- Published
- 2015
39. An instrument to measure fast gas phase radical kinetics at high temperatures and pressures
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Stone, Daniel, primary, Blitz, Mark, additional, Ingham, Trevor, additional, Onel, Lavinia, additional, Medeiros, Diogo J., additional, and Seakins, Paul W., additional
- Published
- 2016
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40. Unimolecular decomposition kinetics of the stabilised Criegee intermediates CH2OO and CD2OO.
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Stone, Daniel, Au, Kendrew, Sime, Samantha, Medeiros, Diogo J., Blitz, Mark, Seakins, Paul W., Decker, Zachary, and Sheps, Leonid
- Abstract
Decomposition kinetics of stabilised CH
2 OO and CD2 OO Criegee intermediates have been investigated as a function of temperature (450–650 K) and pressure (2–350 Torr) using flash photolysis coupled with time-resolved cavity-enhanced broadband UV absorption spectroscopy. Decomposition of CD2 OO was observed to be faster than CH2 OO under equivalent conditions. Production of OH radicals following CH2 OO decomposition was also monitored using flash photolysis with laser-induced fluorescence (LIF), with results indicating direct production of OH in the v = 0 and v = 1 states in low yields. Master equation calculations performed using the Master Equation Solver for Multi-Energy well Reactions (MESMER) enabled fitting of the barriers for the decomposition of CH2 OO and CD2 OO to the experimental data. Parameterisations of the decomposition rate coefficients, calculated by MESMER, are provided for use in atmospheric models and implications of the results are discussed. For CH2 OO, the MESMER fits require an increase in the calculated barrier height from 78.2 kJ mol−1 to 81.8 kJ mol−1 using a temperature-dependent exponential down model for collisional energy transfer with 〈ΔE〉down = 32.6(T/298 K)1.7 cm−1 in He. The low- and high-pressure limit rate coefficients are k1,0 = 3.2 × 10−4 (T/298)−5.81 exp(−12 770/T) cm3 s−1 and k1,∞ = 1.4 × 1013 (T/298)0.06 exp(−10 010/T) s−1 , with median uncertainty of ∼12% over the range of experimental conditions used here. Extrapolation to atmospheric conditions yields k1 (298 K, 760 Torr) = 1.1+1.5−1.1× 10−3 s−1 . For CD2 OO, MESMER calculations result in 〈ΔE〉down = 39.6(T/298 K)1.3 cm−1 in He and a small decrease in the calculated barrier to decomposition from 81.0 kJ mol−1 to 80.1 kJ mol−1 . The fitted rate coefficients for CD2 OO are k2,0 = 5.2 × 10−5 (T/298)−5.28 exp(−11 610/T) cm3 s−1 and k2,∞ = 1.2 × 1013 (T/298)0.06 exp(−9800/T) s−1 , with overall error of ∼6% over the present range of temperature and pressure. The extrapolated k2 (298 K, 760 Torr) = 5.5+9.2−5.5× 10−3 s−1 . The master equation calculations for CH2 OO indicate decomposition yields of 63.7% for H2 + CO2 , 36.0% for H2 O + CO and 0.3% for OH + HCO with no significant dependence on temperature between 400 and 1200 K or pressure between 1 and 3000 Torr. [ABSTRACT FROM AUTHOR]- Published
- 2018
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41. Análise tridimensional da interação solo-estrutura em fundações de concreto armado pelo método dos elementos finitos
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Medeiros, Diogo Soliman, Campos Filho, Americo, Consoli, Nilo Cesar, and Pacheco, Alexandre Rodrigues
- Subjects
Interação solo-estrutura ,Concreto armado ,Elementos finitos ,Fundações (Engenharia) - Abstract
O estudo da interação solo-estrutura em fundações é um tema que certamente necessita de pesquisas mais aprofundadas, já que as soluções empíricas, semi-empíricas ou mesmo as analíticas disponíveis na literatura têm aplicabilidade bastante limitada. Em contrapartida, os modelos computacionais têm a característica intrínseca de abrirem o leque de possibilidades de análise, segundo as mais diversas situações, e da forma mais abrangente possível. Desta forma, o objetivo deste trabalho foi o de desenvolver um programa computacional que realizasse análises elastoplásticas tridimensionais da interação solo-estrutura de fundações rasas de concreto armado. Para tanto o método dos elementos finitos foi utilizado no desenvolvido deste programa computacional. Os elementos finitos empregados na modelagem do concreto e do solo foram elementos isoparamétricos hexaédricos, lineares ou quadráticos. Na modelagem da armadura, a mesma foi considerada através de um modelo incorporado, admitindo-se aderência perfeita entre o concreto e o aço. O comportamento dos materiais foi representado através de modelos elastoplásticos. Para a representação do concreto fissurado, foi utilizado um modelo de fissuras distribuídas. O programa computacional foi implementado na linguagem FORTRAN 90 e as etapas de pós-processamento foram feitas com o uso do programa GiD®. Os resultados obtidos através da aplicação do programa para a simulação do comportamento de fundações rasas em diferentes situações mostram a complexidade de tais problemas. The study of soil-structure interaction on foundations is a topic that certainly needs more in-depth research, since empirical, semi-empirical, or even analytical solutions available in the literature have very limited applicability. On the other hand, computational models have the intrinsic characteristic of opening a spectrum of possibilities when analyzing structures, considering any situation and in a more comprehensive way. Considering this, the objective of this work was the development of a computational program for threedimensional elastoplastic analyses of soil-structure interaction problems on reinforced concrete shallow foundations. To accomplish this, the finite element method was used in the development of the computational program. The finite elements used in the modeling of both reinforced concrete and soil were either the linear or the quadratic isoparametric hexahedron. For the modeling of the reinforcing steel bars, they were considered through an incorporated model, which assumes perfect bonding between concrete and steel rebars .Material behavior was represented through elastoplastic models. A smeared crack model was used to represent cracked concrete. The computational program was implemented in FORTRAN 90 while the post-processing tasks were carried out through the software GiD®. The results obtained through the application of the program to simulate the behavior of shallow foundations in different situations show the complexity of such problems.
- Published
- 2006
42. Evaluation of the Effect of Acute Sibutramine in Female Rats in the Elevated T-Maze and Elevated Plus-Maze Tests
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Santos, Raliny O., primary, de Assunção, Gabriela L. M., additional, de Medeiros, Diogo M. B., additional, de Sousa Pinto, Ícaro A., additional, de Barros, Keizianny S., additional, Soares, Bruno L., additional, André, Eunice, additional, Gavioli, Elaine C., additional, and de Paula Soares-Rachetti, Vanessa, additional
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- 2013
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43. ITP Adjuster 1.0: A New Utility Program to Adjust Charges in the Topology Files Generated by the PRODRG Server
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Medeiros, Diogo de Jesus, primary, Cortopassi, Wilian Augusto, additional, Costa França, Tanos Celmar, additional, and Pimentel, André Silva, additional
- Published
- 2013
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44. Docking and molecular dynamics studies of new potential inhibitors of the human epidermal receptor 2
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Cortopassi, Wilian Augusto, primary, Feital, Rafael José Cavalieri, additional, Medeiros, Diogo de Jesus, additional, Guizado, Teobaldo Ricardo Cuya, additional, França, Tanos Celmar Costa, additional, and Pimentel, André Silva, additional
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- 2012
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45. New Insights in the Atmospheric HONO Formation: New Pathways for N2O4 Isomerization and NO2 Dimerization in the Presence of Water
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de Jesus Medeiros, Diogo, primary and Pimentel, Andre Silva, additional
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- 2011
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46. Da classe média à periferia? O PT nas eleições municipais paulistanas (1996-2012)
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Medeiros, Diogo Frizzo de, primary
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47. ITP Adjuster 1.0: A New Utility Program to Adjust Charges in the Topology Files Generated by the PRODRG Server.
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de Jesus Medeiros, Diogo, Cortopassi, Wilian Augusto, Costa França, Tanos Celmar, and Pimentel, André Silva
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- *
TOPOLOGY , *STRUCTURAL optimization , *UTILITIES (Computer programs) , *CLIENT/SERVER computing , *AB initio quantum chemistry methods , *ATOMIC charges , *COMPUTATIONAL chemistry - Abstract
The suitable computation of accurate atomic charges for the GROMACS topology *.itp files of small molecules, generated in the PRODRG server, has been a tricky task nowadays because it does not calculate atomic charges using an ab initio method. Usually additional steps of structure optimization and charges calculation, followed by a tedious manual replacement of atomic charges in the *.itp file, are needed. In order to assist this task, we report here the ITP Adjuster 1.0, a utility program developed to perform the replacement of the PRODRG charges in the *.itp files of small molecules by ab initio charges. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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48. New Insights in the Atmospheric HONO Formation: New Pathways for N2O4 Isomerization and NO2 Dimerization in the Presence of Water.
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Medeiros, Diogo de Jesus and Pimentel, Andre Silva
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ISOMERIZATION , *HYDROLYSIS , *FREE radicals , *MOLECULAR dynamics , *DENSITY functionals - Abstract
Isomerization of N2O4 and dimerization of NO2 in thin water films on surfaces are believed to be key steps in the hydrolysis of NO2, which generates HONO, a significant precursor to the OH free radical in lower atmosphere and high-energy materials. Born--Oppenheimer molecular dynamics simulations using the density functional theory are carried out for NO2(H2O)m, m ≤ 4, and N2O4(H2O), clusters, n ≤ 7, used to mimic the surface reaction, to investigate the mechanism around room temperature. The results are (i) the NO2 dimerization and N2O4 isomerization reactions occur via two possible pathways, the non-water-assisted and water-assisted mechanisms; (ii) the NO2 dimerization in the presence of water yields either ONONO2(H2O)m or NO3-NO+(H2O) m clusters, but it is also possible to form the HNO3(NO2-)(H3O+)(H2O)m-2 transition state to form HONO and HNO3, directly; (iii) the N2O4 isomerization yields the NO3-NO+(H2O), cluster, but it does not hydrolyze faster than the NO2+NO2 -(H2O). hydrolysis to directly form the HONO and HNO3. New insights for hydrolysis of oxides of nitrogen in and on thin water films on surfaces in the atmosphere are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
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49. Melanoma with osteocartilaginous differentiation
- Author
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Barroso de Carvalho, Bennett and Batista dos Santos Medeiros, Diogo
- Published
- 2022
- Full Text
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50. New Measurements and Calculations on the Kinetics of an Old Reaction: OH + HO 2 → H 2 O + O 2 .
- Author
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Speak TH, Blitz MA, Medeiros DJ, and Seakins PW
- Abstract
Literature rate coefficients for the prototypical radical-radical reaction at 298 K vary by close to an order of magnitude; such variations challenge our understanding of fundamental reaction kinetics. We have studied the title reaction at room temperature via the use of laser flash photolysis to generate OH and HO
2 radicals, monitoring OH by laser-induced fluorescence using two different approaches, looking at the direct reaction and also the perturbation of the slow OH + H2 O2 reaction with radical concentration, and over a wide range of pressures. Both approaches give a consistent measurement of k1,298K ∼1 × 10-11 cm3 molecule-1 s-1 , at the lowest limit of previous determinations. We observe, experimentally, for the first time, a significant enhancement in the rate coefficient in the presence of water, k1,H = (2.17 ± 0.09) × 102 O, 298K-28 cm6 molecule-2 s-1 , where the error is statistical at the 1σ level. This result is consistent with previous theoretical calculations, and the effect goes some way to explaining some, but not all, of the variation in previous determinations of k1,298K . Supporting master equation calculations, using calculated potential energy surfaces at the RCCSD(T)-F12b/CBS//RCCSD/aug-cc-pVTZ and UCCSD(T)/CBS//UCCSD/aug-cc-pVTZ levels, are in agreement with our experimental observations. However, realistic variations in barrier heights and transition state frequencies give a wide range of calculated rate coefficients showing that the current precision and accuracy of calculations are insufficient to resolve the experimental discrepancies. The lower value of k1,298K is consistent with experimental observations of the rate coefficient of the related reaction, Cl + HO2 → HCl + O2 . The implications of these results in atmospheric models are discussed., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)- Published
- 2023
- Full Text
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