54 results on '"Gomes PT"'
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2. Radar – An Important Tool for Horizon Scanning Dissemination in Brazil
- Author
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Gomes, PT, primary, Teixeira Vidal, A, additional, and Souza, A, additional
- Published
- 2017
- Full Text
- View/download PDF
3. Judicialização Da Saúde No Brasil: Proximidade Dos Magistrados Com As Políticas Públicas De Saúde
- Author
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Silva, SN, primary, Gomes, PT, additional, Catanheide, ID, additional, Simabuku, EM, additional, and Rabelo, RB, additional
- Published
- 2017
- Full Text
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4. PHP55 - Judicialização Da Saúde No Brasil: Proximidade Dos Magistrados Com As Políticas Públicas De Saúde
- Author
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Silva, SN, Gomes, PT, Catanheide, ID, Simabuku, EM, and Rabelo, RB
- Published
- 2017
- Full Text
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5. PHP28 - Radar – An Important Tool for Horizon Scanning Dissemination in Brazil
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Gomes, PT, Teixeira Vidal, A, and Souza, A
- Published
- 2017
- Full Text
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6. HT3 - Avanços Do Monitoramento Do Horizonte Tecnológico No Brasil
- Author
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Souza, AB, Teixeira Vidal, A, and Gomes, PT
- Published
- 2017
- Full Text
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7. Effect of Facial Massage on Static Balance in Individuals with Temporomandibular Disorder – a Pilot Study
- Author
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El Hage, PT, MSc, Yasmin, primary, Politti, PT, PhD, Fabiano, additional, Herpich, PT, MSc, Carolina Marciela, additional, Souza, DMd, MSc, Dowglas Fernando Magalhães de, additional, Gomes, PT, MSc, Cid André Fidelis de Paula, additional, Amorim, EEc,PhD, Cesar Ferreira, additional, Gonzalez, PT, PhD, Tabajara De Oliveira, additional, and Biasotto-Gonzalez, PT, PhD, Daniela Aparecida, additional
- Published
- 2013
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8. Analysis of Non-invasive Ventilatory Support Modes: High Flow Nasal Cannula and Non-invasive Ventilation
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Evelim Leal de Freitas Dantas Gomes, PT, Professor
- Published
- 2019
9. Effects of Noninvasive Ventilation Compared to Salbutamol
- Author
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Evelim Leal de Freitas Dantas Gomes, PT, Clinical Professor
- Published
- 2019
10. Environmental influence on the functional ecological structure of benthic macrofaunal communities of the northwest Iberian coast.
- Author
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Alves CM, Gomes MA, Troncoso JS, and Gomes PT
- Subjects
- Animals, Spain, Biodiversity, Aquatic Organisms physiology, Invertebrates physiology, Geologic Sediments chemistry, Ecosystem, Environmental Monitoring
- Abstract
Evaluating the functional structure of benthic macrofaunal communities provides insights into how environmental drivers shape the ecosystem and establishes a baseline knowledge of the communities' dynamics and functioning. This understanding allows the prediction of responses to environmental changes and the implementation of efficient conservation and management strategies. Here we examine the structures and functions of benthic macrofaunal communities on the Northwest Iberian coast concerning environmental factors such as depth, hydrodynamic energy, and bottom type. The results suggest that the community assemblages and their function are structured by factors which influence food availability and habitat heterogeneity. The different sites exhibited different trait compositions and functional structures, indicating that distinct functions are performed according to environmental conditions. The communities found in sandy bottom areas with low hydrodynamic conditions presented frail functionality and demonstrated high vulnerability to alterations in their environment. Conversely, the communities found in rocky bottoms with high hydrodynamic conditions exhibited a fulfilled functional niche space, rendering them more resilient to such changes and less prone to loss of function. Although the analyses did not reveal significant differences in the factor depth, its influence on several factors seems relevant in shaping the functional structure of the communities. These findings highlight the importance of understanding the impact of local environmental conditions on ecosystem functioning, to effectively implement monitoring, management, and conservation strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2024
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11. Unveiling the role of taxonomic sufficiency for enhanced ecosystem monitoring.
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Carreira-Flores D, Rubal M, Cabecinha E, Díaz-Agras G, and Gomes PT
- Subjects
- Animals, Classification methods, Aquatic Organisms physiology, Invertebrates physiology, Environmental Monitoring methods, Biodiversity, Ecosystem
- Abstract
The use of Artificial substrates (AS) as sampling devices addresses challenges in macrofaunal quantitative sampling. While effectively capturing biodiversity patterns, the time-intensitive identification process at the species level remains a substantial challenge. The Taxonomic Sufficiency approach (TS), where only taxa above species level are identified, arises as a potential solution to be tested across different environmental monitoring scenarios. In this paper, we analyzed three AS macrobenthic datasets to evaluate the odds of TS in improving the cost-effective ratio in AS monitoring studies and establish the highest resolution level to detect assemblage changes under different environmental factors. Results indicated that the family level emerged as a pragmatic compromise, balancing precision and taxonomic effort. Cost/benefit analysis supported TS efficiency, maintaining correlation stability until the family level. Results also showed that reducing resolution to family does not entail a significant Loss of Information. This study contributes to the discourse on TS applicability, highlighting its practicality in monitoring scenarios, including spatial-temporal studies, and rapid biodiversity assessments. Additionally, it highlights the "second best approach" of family-level practicality depending on the specific monitoring scenario and recognizes the importance of the species-level "best approach" before applying TS in monitoring studies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2024
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12. Assessing the Seasonal and Spatial Dynamics of Zooplankton through DNA Metabarcoding in a Temperate Estuary.
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Moutinho J, Carreira-Flores D, Gomes PT, Costa FO, and Duarte S
- Abstract
Zooplankton are key components of estuarine trophic networks. However, routine monitoring is hindered by the difficulty of morphology-based identification. DNA-based methods allow us to circumvent some of these hurdles, providing precise species identifications regardless of the taxonomic expertise of the investigator or the developmental stage of the specimens. However, the process is dependent on the completeness of the reference libraries. In this study, we sought to evaluate the potential of DNA metabarcoding to assess the seasonal (summer, autumn, and early spring) and spatial dynamics of zooplankton (four locations spanning ca. 6 km) in the Lima estuary (NW Portugal). Two genetic markers were used: the cytochrome c oxidase subunit I and the V4 hypervariable region of the ribosomal 18S rRNA genes. Overall, 327 species were recovered, and both markers displayed minute overlap (7% were detected with both markers). Species richness, composition, and taxonomic distinctness were majorly influenced by the season, with a declining tendency from summer (highest number of exclusive species, n = 74) to spring. Second to season, the taxa composition was influenced by spatial variation where the most downstream site displayed the highest number of exclusive species, n = 53. A total of 16 non-indigenous species were detected using metabarcoding, but only one ( Austrominus modestus ) has been documented out in the estuary. In conclusion, both the seasonal and spatial gradients influenced the recovered richness, composition, and taxonomic distinctness, confirming the great aptitude of DNA metabarcoding for providing higher density monitoring and shedding new light on the composition and dynamics of complex zooplankton communities.
- Published
- 2023
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13. Genetic diversity and relatedness in captive collared peccaries Dicotyles tajacu (Linnaeus, 1758) (Cetartiodactyla: Tayassuidae) estimated by microsatellite genotyping using high-throughput sequencing: Implications for their conservation and reintroduction.
- Author
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Gomes PT, Rosse IC, Moraes LÂG, Kalapothakis E, de Azevedo CS, Cardoso DC, and Cristiano MP
- Subjects
- Animals, Genotype, Microsatellite Repeats genetics, High-Throughput Nucleotide Sequencing, Genetic Variation, Animals, Zoo genetics, Artiodactyla genetics
- Abstract
The global population of Dicotyles tajacu (Linnaeus, 1758) (Cetartiodactyla: Tayassuidae), commonly known as the collared peccary and distributed in the Neotropics, is currently in decline due to anthropogenic pressures. In this study, five microsatellite loci were used to genetically characterize a group of 20 captive-born collared peccaries intended for reintroduction. This study aimed to evaluate the genetic diversity and relatedness of captive individuals using microsatellite markers. The genetic data generated were used to evaluate the viability of the reintroduction and to propose measures for the management and conservation of this species. In this study, we found relatively high genetic diversity indices, indicating that the group was genetically diverse. Inbreeding coefficients with negative values were observed, indicating an excess of alleles in heterozygosis and an absence of inbreeding. One locus showed deviation from Hardy-Weinberg equilibrium, which may have been caused by the mixing of individuals from different origins. Relatedness analysis indicated that some individuals were highly related, with coefficients indicating they may be first-degree relatives. Our findings indicate that the studied group has enough genetic diversity to be released into nature, but the high individual relatedness found would require the adoption of strategies after the release of animals in the wild to ensure their persistence., (© 2023 Wiley Periodicals LLC.)
- Published
- 2023
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14. New copper(I) complexes of bulky 5-substituted-2-iminopyrrolyl ligands as catalysts for azide-alkyne cycloaddition.
- Author
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Cruz TFC, Lopes PS, Lemos MANDA, Veiros LF, and Gomes PT
- Abstract
Five dinuclear copper(I) complexes of the type [Cu{κ N ,κ N '-5-R-NC
4 H2 -2-C(H)N(2,6-iPr2 C6 H3 )}]2 (1a-e; R = 2,4,6-iPr3 C6 H2 (a), R = 2,6-Me2 C6 H3 (b), R = 3,5-(CF3 )2 C6 H3 (c), R = 2,6-(OMe)2 C6 H2 (d), R = CPh3 (e)) were prepared by the reaction of the respective 5-R-2-iminopyrrolyl potassium salts KLa-e and [Cu(NCMe)4 ]BF4 in moderate yields. These new copper(I) complexes were characterized by NMR spectroscopy, elemental analysis and, in selected cases, by single crystal X-ray diffraction and their structural and electronic features further analyzed by DFT calculations and cyclic voltammetry, respectively. X-ray diffraction studies reveal dimeric Cu structures assembled by 2-iminopyrrolyl bridging ligands adopting a transoid conformation (complexes 1a and 1d), while complexes 1c and 1e displayed a cisoid conformation of those moieties, with respect to the Cu(I) centers. Additionally, VT-1 H NMR and1 H-1 H NOESY NMR experiments on complexes 1a-e exhibited complex fluxional processes in solution, assigned to a conformational inversion of the respective Cu2 N4 C4 metallacycles in all complexes but 1c, accompanied by a cisoid-transoid isomerization in the cases of complexes 1d,e. The Cu(I) complexes were also analyzed by cyclic voltammetry, where all complexes exhibit two oxidation processes, where the first oxidation is reversible, with the exception of 1b and 1c, which also show the highest oxidation potentials. The oxidation potentials follow clear trends related to the structural parameters of the complexes, in particular the Cu⋯Cu distance and the Cu2 N4 C4 macrocycles torsion angles. All new 5-substituted-2-iminopyrrolyl Cu(I) complexes 1a-e served as catalysts for azide-alkyne cycloaddition (CuAAC) reactions, being able to generate the respective 1,2,3-triazole products in yields as high as 82% and turnover frequencies (TOFs) as high as 859 h-1 , after optimizing the conditions. The activity, as measured by the TOF, is in accordance with the oxidation potential of the corresponding complexes, the easier the oxidation, the higher the TOF value. Complex 1-H, where R = H, proved to be a poor catalyst for the same reactions, indicating that the 5-substitution in the ligand framework is crucial in stabilizing any potential catalytic species.- Published
- 2023
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15. 9-Borafluoren-9-yl and diphenylboron tetracoordinate complexes of F- and Cl-substituted 8-quinolinolato ligands: synthesis, molecular and electronic structures, fluorescence and application in OLED devices.
- Author
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Fialho CB, Cruz TFC, Rodrigues AI, Calhorda MJ, Vieira Ferreira LF, Pander P, Dias FB, Morgado J, Maçanita AL, and Gomes PT
- Abstract
Six new four-coordinate tetrahedral boron complexes, containing 9-borafluoren-9-yl and diphenylboron cores attached to orthogonal fluorine- and chlorine-substituted 8-quinolinolato ligand chromophores, have been synthesised, characterised, and applied as emitters in organic light-emitting diodes (OLEDs). An extensive steady-state and time-resolved photophysical study, in solution and in the solid state, resulted in the first-time report of delayed fluorescence (DF) in solid films of 8-quinolinolato boron complexes. The DF intensity dependence on excitation dose suggests that this emission originates from triplet-triplet annihilation (TTA). Density functional theory (DFT) and time-dependent density functional theory (TDDFT) studies give insight into the ground and excited state geometries, electronic structures, absorption energies, and singlet-triplet gaps in these new organoboron luminophores. Finally, given their highly luminescent behaviour, organic light-emitting diode (OLED) devices were produced using the synthesised organoboron compounds as emissive fluorescent dopants. The best OLED displays green-blue ( λ maxEL = 489 nm) electroluminescence with an external quantum efficiency (EQE) of 3.3% and a maximum luminance of 6300 cd m
-2 .- Published
- 2023
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16. Enhancing SIM behaviour in a mononuclear tetrahedral [Co( N , N '-2-iminopyrrolyl) 2 ] complex.
- Author
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Ferreira PS, Malta JF, Bandeira NAG, Allgaier A, van Slageren J, Paixão JA, Almeida M, Pereira LCJ, and Gomes PT
- Abstract
A new homoleptic Co(II) complex bearing two highly sterically congested 2-formiminopyrrolyl N , N '-chelating ligands is reported, displaying slow relaxation of the magnetisation at zero static (DC) field. This compound shows a large value for the zero-field splitting (ZFS) parameter D of -42.6(4) cm
-1 leading to a spin-reversal energy barrier Ueff of 85 cm-1 .- Published
- 2022
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17. Hydrosilylation of Aldehydes and Ketones Catalyzed by a 2-Iminopyrrolyl Alkyl-Manganese(II) Complex.
- Author
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Cruz TFC, Veiros LF, and Gomes PT
- Abstract
A well-defined and very active single-component manganese(II) catalyst system for the hydrosilylation of aldehydes and ketones is presented. First, the reaction of 5-(2,4,6- i Pr
3 C6 H2 )-2-[ N -(2,6- i Pr2 C6 H3 )formimino]pyrrolyl potassium ( KL ) and [MnCl2 (Py)2 ] afforded the binuclear 2-iminopyrrolyl manganese(II) pyridine chloride complex [Mn2 {κ2 N , N' -5-(2,4,6- i Pr3 C6 H2 )-NC4 H2 -2-C(H)═N(2,6- i Pr2 C6 H3 )}2 (Py)2 (μ-Cl)2 ] 1 . Subsequently, the alkylation reaction of complex 1 with LiCH2 SiMe3 afforded the respective (trimethylsilyl)methyl-Mn(II) complex [Mn{κ2 N , N' -5-(2,4,6- i Pr3 C6 H2 )-NC4 H2 -2-C(H)═N(2,6- i Pr2 C6 H3 )}(Py)CH2 SiMe3 ] 2 in a good yield. Complexes 1 and 2 were characterized by elemental analysis,1 H NMR spectroscopy, Evans' method, FTIR spectroscopy, and single-crystal X-ray diffraction. While the crystal structure of complex 1 has been identified as a binuclear entity, in which the Mn(II) centers present pentacoordinate coordination spheres, that of complex 2 corresponds to a monomer with a distorted tetrahedral coordination geometry. Complex 2 proved to be a very active precatalyst for the atom-economic hydrosilylation of several aldehydes and ketones under very mild conditions, with a maximum turnover frequency of 95 min-1 , via a silyl-Mn(II) mechanistic route, as asserted by a combination of experimental and theoretical efforts, the respective silanes were cleanly converted to the respective alcoholic products in high yields.- Published
- 2022
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18. Two better than one: The complementary of different types of artificial substrates on benthic marine macrofauna studies.
- Author
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Carreira-Flores D, Neto R, Ferreira H, Cabecinha E, Díaz-Agras G, and Gomes PT
- Subjects
- Biodiversity, Ecosystem
- Abstract
Non-destructive methodologies based on the use of artificial substrates (AS) for quantitative sampling of macrofauna have been used to solve sampling problems in complex benthic environment, such as rocky reefs. The macrofauna assemblages of two different types of AS (dendritic and crevice), at two different locations were studied. The main goal was to evaluate the complementarity of dendritic and crevice AS when sampling the macrofauna associated with rocky environments, in two scenarios: within the same location and between locations. With this approach, we intend to contribute to the development of a non-destructive sampling methodology based on AS. The hypotheses tested were that i) the assemblages associated with each type of AS would differ between them and, ii) regardless of AS type, assemblages would differ between locations. Our results revealed significant differences after three months between the macrofauna assemblages from dendritic and crevice substrates in both locations and differences between locations irrespective of the AS type used. Hence, due to the high number of species that only were attracted by each type of AS and the species settlement preferences, our findings have shown the complementarity of the two types of AS (dendritic and crevice). This suggests that the mixed use of AS could be the best approach to non-destructive standard monitoring programs based on benthic marine macrofauna., (Copyright © 2021 Elsevier Ltd. All rights reserved.)
- Published
- 2021
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19. Luminescent halogen-substituted 2-(N-arylimino)pyrrolyl boron complexes: the internal heavy-atom effect.
- Author
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Rodrigues AI, Krishnamoorthy P, Gomes CSB, Carmona N, Di Paolo RE, Pander P, Pina J, Sérgio Seixas de Melo J, Dias FB, Calhorda MJ, Maçanita AL, Morgado J, and Gomes PT
- Abstract
A group of new boron complexes [BPh
2 {κ2 N,N'-NC4 H3 -2-C(H)[double bond, length as m-dash]N-C6 H4 X}] (X = 4-Cl 4c, 4-Br 4d, 4-I 4e, 3-Br 4f, 2-Br 4g, 2-I 4h) containing different halogens as substituents in the N-aryl ring have been synthesized and characterized in terms of their molecular properties. Their photophysical characteristics have been thoroughly studied in order to understand whether these complexes exhibit an internal heavy-atom effect. Phosphorescence emission was found for some of the synthesized halogen-substituted boron molecules, particularly for 4g and 4h. DFT and TDDFT calculations showed that the lower energy absorption band resulted from the HOMO to LUMO (π-π*) transition, except for 2-I 4h, where the HOMO-1 to LUMO transition was also involved. The strong participation of iodine orbitals in HOMO-1 is reflected in the calculated absorption spectra of the iodine derivatives, especially 2-I 4h, when spin-orbit coupling (SOC) was included. Organic light-emitting diodes (OLEDs) based on these complexes, in the neat form or dispersed in a matrix, were also fabricated and tested. The devices based on films prepared by thermal vacuum deposition showed the best performance. When neat complexes were used, a maximum luminance (Lmax ) of 1812 cd m-2 was obtained, with a maximum external quantum efficiency (EQEmax ) of 0.15%. An EQEmax of ca. 1% along with a maximum luminance of 494 cd m-2 were obtained for a device fabricated by co-deposition of the boron complex and a host compound (1,3-bis(N-carbazolyl)benzene, mCP).- Published
- 2020
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20. Hippotherapy on postural balance in the sitting position of children with cerebral palsy - Longitudinal study.
- Author
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Moraes AG PT, MSc, Copetti F PhD, Ângelo VR BS, Chiavoloni L BS, and de David AC PhD
- Subjects
- Child, Child, Preschool, Female, Humans, Longitudinal Studies, Male, Cerebral Palsy rehabilitation, Equine-Assisted Therapy methods, Postural Balance, Sitting Position
- Abstract
Purpose : To verify the effects of 12, 24, 36 hippotherapy sessions over time on postural balance while sitting in children with cerebral palsy as well the effects of treatment after one interruption period of 45 days. Methods : Hippotherapy program with a twice-weekly treatment with a total of 13 children aged 5-10 years old. Measurements of postural balance during sitting were performed using the AMTI AccuSway Plus platform. Results : There was a statistically significant reduction in mediolateral and anteroposterior sway after the first 12 hippotherapy sessions, and further significant sway reduction occurred as the treatment progressed. Changes in the center of pressure displacement velocity variable began to occur after 24 sessions. Conclusion : Seated postural balance improved in children with cerebral palsy, as evidenced by lower COP displacement, particularly after a greater number of sessions. After the last evaluations, when completing 36 sessions of hippotherapy, it was verified that the improvements to the postural balance continued to occur. Therefore, further studies with a longer treatment period may help to clarify if, at some point, there is stabilization in the improvement of postural balance. Furthermore, it is important to analyze the impact of hippotherapy on functional activities over time.
- Published
- 2020
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21. Boron complexes of aromatic 5-substituted iminopyrrolyl ligands: synthesis, structure, and luminescence properties.
- Author
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Rodrigues AI, Figueira CA, Gomes CSB, Suresh D, Ferreira B, Di Paolo RE, Pereira DS, Dias FB, Calhorda MJ, Morgado J, Maçanita AL, and Gomes PT
- Abstract
A group of new mononuclear boron chelate compounds [BPh
2 {κ2 N,N'-5-R-NC4 H2 -2-C(H)[double bond, length as m-dash]N-Ar}] (R = Ar = C6 H5 7; R = C6 H5 , Ar = 2,6-iPr2 C6 H3 8; R = Anthracen-9-yl (Anthr), Ar = C6 H5 9; R = Anthr, Ar = 2,6-iPr2 C6 H3 10) were synthesized via the reaction of B(C6 H5 )3 with the corresponding 5-substituted 2-(N-arylformimino)pyrrole ligand precursors 3-6. These complexes were prepared in order to evaluate the luminescence potential derived from the substitution of the position 5 of the pyrrolyl ring with an aromatic group. Compounds 7-10 were photophysically characterized in solution and in the solid state. The 5-phenyl-2-iminopyrrolyl-BPh2 complexes 7 and 8 are blue emitters and have enhanced photoluminescence quantum yields in the solid state (ΦPL ) up to 0.95, whereas the 5-anthracenyl derivatives 9 and 10 have green-bluish fluorescence and a ΦPL of 0.49 and 0.24, respectively. DFT and TDDFT studies were performed, considering the effect of solvent and dispersion, in order to show how the geometries of compounds 7-10 changed from the ground to the excited state, to assign electronic transitions, and to rationalize the observed luminescence. These materials were applied in organic light-emitting diodes (OLEDs), with various device structures, the best showing an external quantum efficiency of 2.75% together with a high luminance of 23 530 cd m-2 .- Published
- 2019
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22. Cobalt(I) Complexes of 5-Aryl-2-iminopyrrolyl Ligands: Synthesis, Spin Isomerism, and Application in Catalytic Hydroboration.
- Author
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Cruz TFC, Veiros LF, and Gomes PT
- Abstract
This work reports the first successful isolation and full characterization of cobalt(I) complexes of 5-aryl-2-iminopyrrolyl ligands. In one approach, when [Co{κ
2 N,N'-5-(2,4,6-R3 -C6 H2 )-NC4 H2 -2-C(H)═N(2,6-i Pr2 -C6 H3 )}(Py)Cl] (R =i Pr, 1a; R = Ph, 1b) were reacted with K(HBEt3 ) or Na(Hg) in toluene, the Co(I) arene complexes [Co{κ2 N,N'-5-(2,4,6-i Pr3 -C6 H2 )-NC4 H2 -2-C(H)═N(2,6-i Pr2 -C6 H3 )}(η6 -C6 H5 CH3 )] (2a) and [ Co{κ2 N,N'-5-[2'-(κ:η6 - C6 H5 )-C6 H2 -4',6'-Ph2 ]-NC4 H2 -2-C(H)═N(2,6-i Pr2 -C6 H3 )}] (2b) were formed. The reaction of complex 1a with KC8 in Et2 O yielded the [Co{κ2 N,N'-5-(2,4,6-i Pr3 -C6 H2 )-NC4 H2 -2-C(H)═N(2,6-i Pr2 -C6 H3 )}]2 (3). On another approach, the metathesis of potassium 5-(2,4,6-triisopropylphenyl)-2-( N-2,6-diisopropylphenylformimino)pyrrolyl (KLa) with CoCl(PMe3 )3 yielded the bis(trimethylphosphine) complex [Co{κ2 N,N'-5-(2,4,6-i Pr3 -C6 H2 )-NC4 H2 -2-C(H)═N(2,6-i Pr2 -C6 H3 )}(PMe3 )2 ] (4) in a good yield. Complexes 2a, 3, and 4 are paramagnetic, high-spin species, while 2b is a diamagnetic complex. Compound 2b exhibited a spin isomerism behavior ( S = 0 ↔ S = 1) as determined by variable-temperature1 H NMR experiments (Δ H° = 7.7 kcal mol-1 ), being also supported by computational studies (Δ E = 4.2 kcal mol-1 ). All complexes were tested in the hydroboration of styrene with pinacolborane (HBPin), with complex 4 exclusively yielding the respective anti-Markovnikov addition product. Additionally, all complexes catalyzed the fast and quantitative hydroboration of benzaldehyde with HBPin.- Published
- 2018
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23. New phenyl-nickel complexes of bulky 2-iminopyrrolyl chelates: synthesis, characterisation and application as aluminium-free catalysts for the production of hyperbranched polyethylene.
- Author
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Figueira CA, Lopes PS, Gomes CSB, Gomes JCS, Lemos F, and Gomes PT
- Abstract
A family of mono(2-iminopyrrolyl) complexes with the general formula [Ni{κ2N,N'-5-(aryl)-NC4H2-2-C(H)[double bond, length as m-dash]N-2,6-(aryl)}(C6H5)(PPh3)] were obtained from the reaction of the sodium salts of the newly synthesised 5-aryl-2-(N-arylformimino)pyrroles with the square planar complex trans-[Ni(C6H5)(PPh3)2Cl]. These new iminopyrrole ligand precursors, designed with increasing bulkiness and different electronic properties, and their corresponding nickel(ii) complexes were characterised by NMR spectroscopy and elemental analysis, and their structural features were analysed by single crystal X-ray diffraction. The nickel complexes were tested as aluminium-free catalysts for the polymerisation of ethylene, at low to moderate pressures and different temperatures and in the absence or presence of the phosphine scavenger [Ni(COD)2], giving rise to catalytic activities in the range of 3.61-73.12 kgPE molNi-1 h-1 bar-1. The polyethylene products formed in these catalytic reactions were characterised by GPC/SEC and NMR spectroscopy. Generally, low molecular weight (Mn 510-1300 g mol-1) low viscosity oils were obtained, presenting high branching degrees (80-125 branches per 1000 C atoms), which are characteristic of hyperbranched polyethylene products. In particular, polymerisation reactions using catalyst 7 led to higher viscosity oils with molecular weights between 11 000 and 20 000 g mol-1, and branching degrees of 100-120 branches per 1000 C atoms.
- Published
- 2018
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24. Synthesis and Characterization of Isosorbide-Based Polyurethanes Exhibiting Low Cytotoxicity Towards HaCaT Human Skin Cells.
- Author
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Gregorí Valdés BS, Gomes CSB, Gomes PT, Ascenso JR, Diogo HP, Gonçalves LM, Galhano Dos Santos R, Ribeiro HM, and Bordado JC
- Abstract
The synthesis of four samples of new polyurethanes was evaluated by changing the ratio of the diol monomers used, poly(propylene glycol) (PPG) and D-isosorbide, in the presence of aliphatic isocyanates such as the isophorone diisocyanate (IPDI) and 4,4'-methylenebis(cyclohexyl isocyanate) (HMDI). The thermal properties of the four polymers obtained were determined by DSC, exhibiting T
g values in the range 55⁻70 °C, and their molecular structure characterized by FTIR, ¹H, and13 C NMR spectroscopies. The diffusion coefficients of these polymers in solution were measured by the Pulse Gradient Spin Echo (PGSE) NMR method, enabling the calculation of the corresponding hydrodynamic radii in diluted solution (1.62⁻2.65 nm). The molecular weights were determined by GPC/SEC and compared with the values determined by a quantitative13 C NMR analysis. Finally, the biocompatibility of the polyurethanes was assessed using the HaCaT keratinocyte cell line by the MTT reduction assay method showing values superior to 70% cell viability.- Published
- 2018
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25. Hydroboration of Terminal Olefins with Pinacolborane Catalyzed by New Mono(2-Iminopyrrolyl) Cobalt(II) Complexes.
- Author
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Cruz TFC, Lopes PS, Pereira LCJ, Veiros LF, and Gomes PT
- Abstract
The 5-substituted 2-aryliminopyrrolyl ligand precursors of the type 5-R-2-[ N-(2,6-diisopropylphenyl)formimino]-1 H-pyrrole (R = 2,6-Me
2 -C6 H3 (1a), 2,4,6-i Pr3 -C6 H2 (1b), 2,4,6-Ph3 -C6 H3 (1c; reported in this work), anthracen-9-yl (1d), CPh3 (1e; reported in this work)) were treated with K[N(SiMe3 )2 ] in toluene to yield the respective 5-R-2-[ N-(2,6-diisopropylphenyl)formimino]pyrrolyl potassium salts 2a-e in high yields. The paramagnetic 15-electron Co(II) complexes of the type [Co{κ2 N,N'-5-R-NC4 H2 -2-C(H)═N(2,6-i Pr2 -C6 H3 )}(Py)Cl] (3a-e; Py = pyridine) were prepared by salt metathesis of CoCl2 (Py)4 with the respective potassium salts 2a-e in moderate to good yields. When the CoCl2 (THF)1.5 precursor was combined with the in situ prepared sodium salt of ligand precursor 1b, the trinuclear complex [Co{κ2 N, N'-5-(2,4,6-i Pr3 -C6 H2 )-NC4 H2 -2-C(H)═N(2,6-i Pr2 -C6 H3 )}(μ-Cl)]2 [(μ-Cl)2 Co(THF)2 ] (4) was obtained in high yields. Complexes 3a-e have high-spin electronic configurations both in solution and in the solid state. X-ray diffraction studies of complexes 3a,e confirmed distorted tetrahedral coordination geometries. Complex 4, on the other hand, is a linear trinuclear Co(II)-Co(II)-Co(II) complex with two terminal distorted tetrahedral four-coordinate sites and a central octahedral six-coordinate site, all in the high-spin state, S = 3/2, as confirmed by the magnetization measurements and DFT calculations. Solid-state magnetic measurements in both complexes 3a and 4 point to paramagnetic behavior with a significant contribution of spin-orbit coupling. Additionally, intramolecular antiferromagnetic coupling of the adjacent cobalt atoms is observed in 4. The Co(II) family 3a-d, on activation with K(HBEt3 ), catalyzed the hydroboration of several α-olefins with pinacolborane, in good to high yields (50-80%). This system almost exclusively yielded the anti-Markovnikov (a-Mk) addition product, except when styrene was used, where the selectivity in the Markovnikov (Mk) product increased with increasing steric bulkiness of the 5-R-2-iminopyrrolyl substituent, with the a-Mk:Mk molar ratio varying from 2.33:1 (3a, R = 2,6-Me2 -C6 H3 ) to 0.75:1 (3c, R = 2,4,6-Ph3 -C6 H3 ). Preliminary mechanistic studies indicate that the activation by K(HBEt3 ) gave rise to a Co(I) species, the catalyst system likely following an oxidative addition pathway.- Published
- 2018
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26. ILs through the looking glass: electrostatics and structure probed using charge-inverted ionic liquid pairs.
- Author
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Cruz TFC, Shimizu K, Esperança JMSS, Rebelo LPN, Gomes PT, and Canongia Lopes JN
- Abstract
Ionic liquids combining potassium cations with 1-alkyl-3-methylcyclopentadienyl anions, K[C
n C1 Cp] (n = 4, 6) have been synthesized. Differential scanning calorimetry measurements have shown that K[C4 C1 Cp] and K[C6 C1 Cp] melt without decomposition at around 90 °C. These two ionic liquids are the charge-inverted counterparts of [C4 C1 Im]Cl and [C6 C1 Im]Cl, two common ionic liquids. The concept of charge-inverted ionic pairs is used to explore the nature of the interactions and structure in different ionic compounds, from simple alkali halide salts to ionic liquids based on complex molecular ions. Different sets of experimental data, empirical correlations and molecular dynamics simulations are used to that effect.- Published
- 2018
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27. Boron complexes of aromatic ring fused iminopyrrolyl ligands: synthesis, structure, and luminescence properties.
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Suresh D, Ferreira B, Lopes PS, Gomes CS, Krishnamoorthy P, Charas A, Vila-Viçosa D, Morgado J, Calhorda MJ, Maçanita AL, and Gomes PT
- Abstract
The condensation reactions of 2-formylindole (1) or 2-formylphenanthro[9,10-c]pyrrole (2) with various aromatic amines afforded the corresponding phenyl or phenanthrene ring fused mono-/bis-iminopyrrole ligand precursors 3-8, which, upon reaction with BPh
3 in an appropriate molar ratio, led to the new mono- and diboron chelate compounds Ph2 B[NC8 H5 C(H)[double bond, length as m-dash]N-2,6-Ar] (Ar = 2,6-iPr2 C6 H3 9; C6 H5 10), Ph2 B[(NC8 H5 C(H)[double bond, length as m-dash]N)2 -1,4-C6 H4 ]BPh2 11, Ph2 B(NC16 H9 C(H)[double bond, length as m-dash]N-Ar) (Ar = 2,6-iPr2 C6 H3 12; C6 H5 13), and Ph2 B[(NC16 H9 C(H)[double bond, length as m-dash]N)2 -1,4-C6 H4 ]BPh2 14, respectively. Boron complexes 12-14, containing a phenanthrene fragment fused to the pyrrolyl C3-C4 bond, are highly fluorescent in solution, with quantum efficiencies of 37%, 61% and 58% (in THF), respectively, their emission colours ranging from blue to orange depending on the extension of π-conjugation. Complexes 9-11, containing a benzene fragment fused to the pyrrolyl C4-C5 bond, are much weaker emitters, exhibiting quantum efficiencies of 10%, 7% and 6%, respectively. DFT and TDDFT calculations showed that 2,6-iPr2 C6 H3 N-substituents or, to a smaller extent, the indolyl group prevent a planar geometry of the ligand in the excited state and reveal the existence of a low energy weak band in all the indolyl complexes, which is responsible for the different optical properties. Non-doped single-layer light-emitting diodes (OLEDs) were fabricated with complexes 9-14, deposited by spin coating, that of complex 13 revealing a maximum luminance of 198 cd m-2 .- Published
- 2016
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28. Starting a DNA barcode reference library for shallow water polychaetes from the southern European Atlantic coast.
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Lobo J, Teixeira MA, Borges LM, Ferreira MS, Hollatz C, Gomes PT, Sousa R, Ravara A, Costa MH, and Costa FO
- Subjects
- Animals, DNA, Mitochondrial genetics, Gene Library, Portugal, Sequence Analysis, DNA, DNA Barcoding, Taxonomic methods, Polychaeta classification, Polychaeta genetics
- Abstract
Annelid polychaetes have been seldom the focus of dedicated DNA barcoding studies, despite their ecological relevance and often dominance, particularly in soft-bottom estuarine and coastal marine ecosystems. Here, we report the first assessment of the performance of DNA barcodes in the discrimination of shallow water polychaete species from the southern European Atlantic coast, focusing on specimens collected in estuaries and coastal ecosystems of Portugal. We analysed cytochrome oxidase I DNA barcodes (COI-5P) from 164 specimens, which were assigned to 51 morphospecies. To our data set from Portugal, we added available published sequences selected from the same species, genus or family, to inspect for taxonomic congruence among studies and collection location. The final data set comprised 290 specimens and 79 morphospecies, which generated 99 Barcode Index Numbers (BINs) within Barcode of Life Data Systems (BOLD). Among these, 22 BINs were singletons, 47 other BINs were concordant, confirming the initial identification based on morphological characters, and 30 were discordant, most of which consisted on multiple BINs found for the same morphospecies. Some of the most prominent cases in the latter category include Hediste diversicolor (O.F. Müller, 1776) (7), Eulalia viridis (Linnaeus, 1767) (2) and Owenia fusiformis (delle Chiaje, 1844) (5), all of them reported from Portugal and frequently used in ecological studies as environmental quality indicators. Our results for these species showed discordance between molecular lineages and morphospecies, or added additional relatively divergent lineages. The potential inaccuracies in environmental assessments, where underpinning polychaete species diversity is poorly resolved or clarified, demand additional and extensive investigation of the DNA barcode diversity in this group, in parallel with alpha taxonomy efforts., (© 2015 John Wiley & Sons Ltd.)
- Published
- 2016
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29. First examples of neutral and cationic indenyl nickel(II) complexes bearing arsine or stibine ligands: highly active catalysts for the oligomerisation of styrene.
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Gomes CS, Krishnamoorthy P, Silva LC, Costa SI, Gomes PT, Jiménez-Tenorio M, Valerga P, and Puerta MC
- Abstract
New indenyl nickel(ii) complexes bearing arsine or stibine ligands synthesised by a new methodology exhibit very high catalytic activities for the oligomerisation of styrene.
- Published
- 2015
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30. Discordant predictions of residual activity could impact dolutegravir prescription upon raltegravir failure.
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Theys K, Abecasis A, Libin P, Gomes PT, Cabanas J, Camacho RJ, and Van Laethem K
- Subjects
- Clinical Decision-Making, Drug Prescriptions, Drug Resistance, Viral drug effects, Genotype, HIV Infections diagnosis, HIV Integrase Inhibitors pharmacology, HIV-1 drug effects, Heterocyclic Compounds, 3-Ring pharmacology, Humans, Microbial Sensitivity Tests, Mutation, Oxazines, Piperazines, Prognosis, Pyridones, Treatment Failure, Treatment Outcome, HIV Infections drug therapy, HIV Infections virology, HIV Integrase Inhibitors therapeutic use, HIV-1 genetics, Heterocyclic Compounds, 3-Ring therapeutic use
- Abstract
Background: Dolutegravir is approved for the treatment of HIV-1 patients exposed to other integrase inhibitors, but the decision to use dolutegravir in this setting should be informed by drug resistance testing., Objectives: This study determined the extent of disagreement in predicted residual dolutegravir activity after raltegravir use, and identified individual mutational patterns for which uncertainty exists among HIV-1 expert systems., Study Design: Mutation patterns were classified in raltegravir signature pathways including positions 143, 148 and 155, and interpreted into clinically informative resistance levels using genotypic drug resistance interpretation systems ANRS v24, HIVdb v7.0 and Rega v9.1.0, and instructions of dolutegravir use as approved by the Food and Drug Administration and the European Medicines Agency., Results: In 216HIV-1 patients failing raltegravir-therapy, 87% patients displayed mutations associated with resistance towards integrase inhibitors. A total of 141 unique mutational patterns were observed, with N155H (25.4%), Q148H (16.2%) and Y143R (8.3%) the most prevalent signature mutations. The Q148 pathway occurred almost exclusively in HIV-1 subtype B viruses. Concordances in predicted dolutegravir susceptibility scores among 5 systems were obtained in 57.8% of patients, and concordant intermediate resistant and concordant resistant scores were only observed in 6.5% and 0.9% of patients, respectively. However, systems individually scored higher levels of dolutegravir intermediate resistance and resistance, ranging from 4.2% to 10.2% and from 14.8% to 22.7% of patients, respectively. A consensus on interpreting the extent of residual activity was lacking in 34.7% of patients and was highly resistance pathway-specific., Conclusions: Dolutegravir may potentially be effective in the majority of HIV-1 patients failing raltegravir, but concern over the uncertainty in predicted residual activity could withhold clinicians from prescribing dolutegravir during its clinical assessment., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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31. Luminescent Di- and Trinuclear Boron Complexes Based on Aromatic Iminopyrrolyl Spacer Ligands: Synthesis, Characterization, and Application in OLEDs.
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Suresh D, Gomes CS, Lopes PS, Figueira CA, Ferreira B, Gomes PT, Di Paolo RE, Maçanita AL, Duarte MT, Charas A, Morgado J, Vila-Viçosa D, and Calhorda MJ
- Abstract
New bis- and tris(iminopyrrole)-functionalized linear (1,2-(HNC4 H3 -C(H)N)2 -C6 H4 (2), 1,3-(HNC4 H3 -C(H)N)2 -C6 H4 (3), 1,4-(HNC4 H3 -C(H)N)2 -C6 H4 (4), 4,4'-(HNC4 H3 -C(H)N)2 -(C6 H4 -C6 H4 ) (5), 1,5-(HNC4 H3 C-(H)N)2 -C10 H6 (6), 2,6-(HNC4 H3 C-(H)N)2 -C10 H6 (7), 2,6-(HNC4 H3 C-(H)N)2 -C14 H8 (8)) and star-shaped (1,3,5-(HNC4 H3 -C(H)N-1,4-C6 H4 )3 -C6 H3 (9)) π-conjugated molecules were synthesized by the condensation reactions of 2-formylpyrrole (1) with several aromatic di- and triamines. The corresponding linear diboron chelate complexes (Ph2 B[1,3-bis(iminopyrrolyl)-phenyl]BPh2 (10), Ph2 B[1,4-bis(iminopyrrolyl)-phenyl]BPh2 (11), Ph2 B[4,4'-bis(iminopyrrolyl)-biphenyl]BPh2 (12), Ph2 B[1,5-bis(iminopyrrolyl)-naphthyl]BPh2 (13), Ph2 B[2,6-bis(iminopyrrolyl)-naphthyl]BPh2 (14), Ph2 B[2,6-bis(iminopyrrolyl)-anthracenyl]BPh2 (15)) and the star-shaped triboron complex ([4',4'',4'''-tris(iminopyrrolyl)-1,3,5-triphenylbenzene](BPh2 )3 (16)) were obtained in moderate to good yields, by the treatment of 3-9 with B(C6 H5 )3 . The ligand precursors are non-emissive, whereas most of their boron complexes are highly fluorescent; their emission color depends on the π-conjugation length. The photophysical properties of the luminescent polyboron compounds were measured, showing good solution fluorescence quantum yields ranging from 0.15 to 0.69. DFT and time-dependent DFT calculations confirmed that molecules 10 and 16 are blue emitters, because only one of the iminopyrrolyl groups becomes planar in the singlet excited state, whereas the second (and third) keeps the same geometry. Compound 13, in which planarity is not achieved in any of the groups, is poorly emissive. In the other examples (11, 12, 14, and 15), the LUMO is stabilized, narrowing the gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO-LUMO), and the two iminopyrrolyl groups become planar, extending the size of the π-system, to afford green to yellow emissions. Organic light-emitting diodes (OLEDs) were fabricated by using the new polyboron complexes and their luminance was found to be in the order of 2400 cd m(-2) , for single layer devices, increasing to 4400 cd m(-2) when a hole-transporting layer is used., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2015
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32. Autism in Brazil: a systematic review of family challenges and coping strategies.
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Gomes PT, Lima LH, Bueno MK, Araújo LA, and Souza NM
- Subjects
- Adolescent, Autistic Disorder diagnosis, Brazil, Child, Child, Preschool, Delayed Diagnosis adverse effects, Health Services Accessibility, Humans, Mothers psychology, Social Support, Adaptation, Psychological, Attitude to Health, Autistic Disorder psychology, Cost of Illness, Parents psychology
- Abstract
Objective: To describe the challenges faced by families caring for children with autism spectrum disorder (ASD) in Brazil and the coping strategies employed., Sources: Systematic review of articles published until September of 2013, without language restrictions, using quality appraisal (AMSTAR and CASP/Oxford instruments)., Summary of the Findings: The literature shows parental emotional overload as one of the main challenges faced by families, especially mothers. The main stressors were diagnostic postponement, difficulty dealing with the diagnosis and associated symptoms, and poor access to health services and social support. The predominant coping strategies found included information exchange between affected families and integrated healthcare network for patient and family support., Conclusion: ASD exerts strong influence on family dynamics, resulting in caregiver overload, especially in mothers. The Brazilian Unified Health System needs to provide comprehensive, continuous, and coordinated care to strengthen the patient-family dyad and promote the full development and societal inclusion of children with ASD., (Copyright © 2014 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.)
- Published
- 2015
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33. Copper(II) complexes of bis(aryl-imino)acenaphthene ligands: synthesis, structure, DFT studies and evaluation in reverse ATRP of styrene.
- Author
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Fliedel C, Rosa V, Santos CI, Gonzalez PJ, Almeida RM, Gomes CS, Gomes PT, Lemos MA, Aullón G, Welter R, and Avilés T
- Subjects
- Acenaphthenes analysis, Copper analysis, Crystallography, X-Ray, Ligands, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods, Styrene analysis, Acenaphthenes chemistry, Copper chemistry, Styrene chemistry
- Abstract
Two new Ar-BIAN Cu(II) complexes (where Ar-BIAN = bis(aryl-imino)acenaphthene) of formulations [CuCl2(Mes-BIAN)] (1) (Mes = 2,4,6-Me3C6H2) and [CuCl2(Dipp-BIAN)] (2) (Dipp = 2,6-iPr2C6H3) were synthesised by direct reaction of CuCl2 suspended in dichloromethane with the respective ligands Mes-BIAN (L1) and Dipp-BIAN (L2), dissolved in dichloromethane, under an argon atmosphere. Attempts to obtain these compounds by solubilising CuCl2 in methanol and adding a dichloromethane solution of the corresponding ligand, under aerobic conditions, gave also compound 1, but, in the case of L2, the Cu(I) dimer [CuCl(Dipp-BIAN)]2 (3) was obtained instead of compound 2. The compounds were fully characterised by elemental analyses, MALDI-TOF mass spectrometry, FT-IR, (1)H NMR and EPR spectroscopic techniques. The solid-state molecular structures of compounds 1-3 were determined by single crystal X-ray diffraction, showing the expected chelation of the Ar-BIAN ligands and two chloride ligands completing the coordination sphere of the Cu(II) centre. In the case of the complex 1, an intermediate coordination geometry around the Cu(II) centre, between square planar and tetrahedral, was revealed, while the complex 2 showed an almost square planar geometry. The structural differences and evaluation of energetic changes were rationalised by DFT calculations. Analysis of the electrochemical behaviour of complexes 1-3 was performed by cyclic voltammetry and the experimental redox potentials for Cu(II)/Cu(I) pairs have been compared with theoretical values calculated by DFT in the gas phase and in dichloromethane and methanol solutions. The complex 1 exhibited good activity in the reverse atom transfer radical polymerisation (ATRP) of styrene.
- Published
- 2014
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34. Tunable fluorophores based on 2-(N-arylimino)pyrrolyl chelates of diphenylboron: synthesis, structure, photophysical characterization, and application in OLEDs.
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Suresh D, Lopes PS, Ferreira B, Figueira CA, Gomes CS, Gomes PT, Di Paolo RE, Maçanita AL, Duarte MT, Charas A, Morgado J, and Calhorda MJ
- Subjects
- Ligands, Models, Molecular, Molecular Structure, Organic Chemicals chemistry, Pyrroles chemistry, Boranes chemistry, Fluorescent Dyes chemistry, Organic Chemicals chemical synthesis, Pyrroles chemical synthesis
- Abstract
Reactions of 2-(N-arylimino)pyrroles (HNC4H3C(H)=N-Ar) with triphenylboron (BPh3) in boiling toluene afford the respective highly emissive N,N'-boron chelate complexes, [BPh2 {κ(2)N,N'-NC4H3C(H)=N-Ar}] (Ar=C6H5 (12), 2,6-Me2-C6H3 (13), 2,6-iPr2-C6H3 (14), 4-OMe-C6H4 (15), 3,4-Me2-C6 H3 (16), 4-F-C6H4 (17), 4-NO2-C6H4 (18), 4-CN-C6H4 (19), 3,4,5-F3-C6H2 (20), and C6F5 (21)) in moderate to high yields. The photophysical properties of these new boron complexes largely depend on the substituents present on the aryl rings of their N-arylimino moieties. The complexes bearing electron-withdrawing aniline substituents 17-20 show more intense (e.g., ϕf =0.71 for Ar=4-CN-C6H4 (19) in THF), higher-energy (blue) fluorescent emission compared to those bearing electron-donating substituents, for which the emission is redshifted at the expense of lower quantum yields (ϕf=0.13 and 0.14 for Ar=4-OMe-C6H4 (15) and 3,4-Me2-C6H3 (16), respectively, in THF). The presence of substituents bulkier than a hydrogen atom at the 2,6-positions of the aryl groups strongly restricts rotation of this moiety towards coplanarity with the iminopyrrolyl ligand framework, inducing a shift in the emission to the violet region (λmax =410-465 nm) and a significant decrease in quantum yield (ϕf=0.005, 0.023, and 0.20 for Ar=2,6-Me2-C6H3 (13), 2,6-iPr2-C6H3 (14), and C6F5 (21), respectively, in THF), even when electron-withdrawing groups are also present. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations have indicated that the excited singlet state has a planar aryliminopyrrolyl ligand, except when prevented by steric hindrance (ortho substituents). Calculated absorption maxima reproduce the experimental values, but the error is higher for the emission wavelengths. Organic light-emitting diodes (OLEDs) have been fabricated with the new boron complexes, with luminances of the order of 3000 cd m(-2) being achieved for a green-emitting device., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2014
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35. Cassava interspecific hybrids with increased protein content and improved amino acid profiles.
- Author
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Gomes PT and Nassar NM
- Subjects
- Cyanides chemistry, Diploidy, Plant Roots chemistry, Tetraploidy, Amino Acids chemistry, Chimera, Manihot chemistry, Manihot genetics, Plant Proteins chemistry, Plant Proteins metabolism
- Abstract
Cassava (Manihot esculenta) is a principal food for large populations of poor people in the tropics and subtropics. Its edible roots are poor in protein and lack several essential amino acids. Interspecific hybrids may acquire high protein characteristics from wild species. We analyzed 19 hybrids of M. esculenta with its wild relative, M. oligantha, for crude protein, amino acid profile, and total cyanide. Some hybrids produced roots with high protein content of up to 5.7%, while the common cultivar that we examined had just 2.3% crude protein. The essential amino acids alanine, phenylalanine, and valine were detected in the hybrids. The sulfur-containing amino acids cysteine and methionine were found at relatively high concentrations in the roots of 4 hybrids. The proportion of lysine in one hybrid was 20 times higher than in the common cultivar. The levels of total cyanide ranged from 19.73 to 172.56 mg/kg and most of the roots analyzed were classified as "non-toxic" and "low toxic". Furthermore, 2 progenies showed reasonable levels of cyanide, but higher protein content and amino acid profile more advantageous than the common cassava.
- Published
- 2013
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36. Photophysical properties of iminopyrrolyl boron complexes: a DFT interpretation.
- Author
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Calhorda MJ, Suresh D, Gomes PT, Di Paolo RE, and Maçanita AL
- Abstract
The three compounds [BPh(2)(κ(2)N,N'-NC(4)H(3)C(H)=N-C(6)H(5))] (A), [BPh(2)(κ(2)N,N'-NC(4)H(3)C(H)=N-1,4-C(6)H(4)-N=H)C-H(3)C(4)N-N,N'κ(2))BPh(2)] (B) and [BPh(2)(κ(2)N,N'-NC(4)H(3)C(H)=N-4,4'-C(6)H(4)-C(6)H(4)-N=(H)C-H(3)C(4)N-N,N'κ(2))BPh(2)] (C) are blue to green light emitters with average to excellent quantum yields. DFT and TD-DFT calculations were performed in order to understand their behaviour. The geometry of their ground and singlet excited state was optimised, and their absorption patterns and emission were calculated. The large dihedral angles between the planes of the N-aryl and 2-formiminopyrrolyl moieties of the chelating ligand drop considerably, leading to an almost planar geometry in the singlet state. In the three species, the lowest energy absorption occurs at 383, 428, and 419 nm, being calculated at 377, 502, and 529 nm in the gas-phase (slightly shifted in the right direction in THF). It results from a HOMO to LUMO excitation, and was assigned to a transition between π and π* orbitals (ILCT) of the iminopyrrolyl ligand, despite small differences in the exact composition of the HOMO and LUMO in A, B, and C. Introduction of the LB94 functional did not improve the calculated absorption wavelengths, but PBE0 with an all electron basis set within the SOPERT approximation led to better agreement with the experimental absorption maxima and a good reproduction of the excited state lifetimes. The estimated emission wavelengths reproduce the experimental trends.
- Published
- 2012
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37. Syntheses and photophysical properties of new iminopyrrolyl boron complexes and their application in efficient single-layer non-doped OLEDs prepared by spin coating.
- Author
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Suresh D, Gomes CS, Gomes PT, Di Paolo RE, Maçanita AL, Calhorda MJ, Charas A, Morgado J, and Duarte MT
- Subjects
- Ligands, Luminescence, Molecular Structure, Boron Compounds chemistry, Organometallic Compounds chemistry, Pyrroles chemistry
- Abstract
Efficient non-doped OLEDs have been achieved using new binuclear tetracoordinate organoboron complexes containing 2-(N-aryl)formiminopyrrolyl ligands.
- Published
- 2012
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38. Synthesis and structural characterisation of (aryl-BIAN)copper(I) complexes and their application as catalysts for the cycloaddition of azides and alkynes.
- Author
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Li L, Lopes PS, Rosa V, Figueira CA, Lemos MA, Duarte MT, Avilés T, and Gomes PT
- Subjects
- Catalysis, Electrochemistry, X-Ray Diffraction, Alkynes chemistry, Azides chemistry, Chemistry Techniques, Synthetic methods, Copper chemistry, Imines chemistry, Organometallic Compounds chemical synthesis, Organometallic Compounds chemistry
- Abstract
A series of Ar-BIAN-based copper(I) complexes (where Ar-BIAN = bis(aryl)acenaphthenequinonediimine) were synthesised and characterised by (1)H and (13)C NMR spectroscopies, FT-IR spectroscopy, MALDI-TOF-MS spectrometry, cyclic voltammetry and single crystal X-ray diffraction. The bis-chelated complexes of general formula [Cu(Ar-BIAN)(2)]BF(4) (where Ar = C(6)H(5) (1), 4-iPrC(6)H(4) (3), 2-iPrC(6)H(4) (4)) were prepared by reaction of [Cu(NCMe)(4)]BF(4) with two equivalents of the corresponding Ar-BIAN ligands, in dichloromethane, while the mono-chelated complexes of the type [Cu(Ar-BIAN)L(2)]BF(4) (where Ar = 2,6-iPr(2)C(6)H(3), L = PhCN (6); Ar = 4-iPrC(6)H(4), L = PPh(3) (7)) were readily accessible by treatment of [Cu(NCR)(4)]BF(4) (R = Me, Ph) with one equivalent of the corresponding Ar-BIAN ligands in the absence or presence of two equivalents of PPh(3), in the same solvent. The structures of complexes 3, 4, 6 and 7 were obtained by single crystal X-ray diffraction, showing distorted tetrahedral geometries around the copper centres in all cases. The electrochemical studies of these complexes and of the already reported [Cu(2,4,6-Me(3)C(6)H(2)-BIAN)(2)]BF(4) (2) and [Cu(2,6-iPr(2)C(6)H(3)-BIAN)(NCMe)(2)] (5), demonstrated that the bis-chelated complexes 1-4 undergo a reversible one-electron reduction or oxidation processes on copper, while the mono-chelated complexes 5-7 show a partially reversible oxidation and an irreversible reduction feature. Both kinds of (Ar-BIAN)copper(I) complexes are active catalysts for the copper(I)-catalysed azide-alkyne cycloaddition reaction (CuAAC). Complex 7, bearing PPh(3) ligands, exhibits the highest catalytic activity, which is comparable with that of the typical CuSO(4)-sodium ascorbate catalyst system.
- Published
- 2012
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39. Iminopyrrole derivatives containing electron-withdrawing substituents: the formation of dimers and supramolecular arrangements.
- Author
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Gomes CS, Figueira CA, Lopes PS, Suresh D, Gomes PT, and Duarte MT
- Subjects
- Crystallography, X-Ray, Electrons, Hydrogen Bonding, Molecular Structure, Imines chemistry, Nitriles chemistry, Pyrroles chemistry
- Abstract
The crystal structures of two p-substituted phenylformiminopyrrole derivatives, namely 2-[(4-fluorophenyl)iminomethyl]pyrrole, C(11)H(9)FN(2), (1), and 2-[(1H-pyrrol-2-ylmethylidene)amino]benzonitrile, C(12)H(9)N(3), (2), bear F and C[triple-bond]N electron-withdrawing groups, respectively. Both structures feature two independent molecules in the asymmetric unit forming dimers via N-H...N hydrogen bonds. In the case of (1), each dimer interacts with two other dimers via C-H...F contacts, thus forming one-dimensional chains in the b direction, whereas in the case of (2), a weak C-H...N interaction connects the dimers in one-dimensional chains in the (110) direction.
- Published
- 2011
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40. New tetradentate N,N,N,N-chelating α-diimine ligands and their corresponding zinc and nickel complexes: synthesis, characterisation and testing as olefin polymerisation catalysts.
- Author
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Li L, Gomes CS, Gomes PT, Duarte MT, and Fan Z
- Abstract
A series of zinc complexes of the general formula {[ZnCl(ArN=C(An)-C(An)=NAr)](+)}(2)[Zn(2)Cl(6)](2-) (where Ar = 2-(1-benzyl-1H-1,2,3-triazol-4-yl)phenyl 2a, 2-(1-(1-phenylethyl)-1H-1,2,3-triazol-4-yl)phenyl 2b, 2-(1-phenyl-1H-1,2,3-triazol-4-yl)phenyl 2c; An = acenaphthene backbone) were prepared by the condensation of acenaphthenequinone with the corresponding o-triazolyl-substituted anilines (2-(1-benzyl-1H-1,2,3-triazol-4-yl)aniline 1a, 2-(1-(1-phenylethyl)-1H-1,2,3-triazol-4-yl)aniline 1b, 2-(1-phenyl-1H-1,2,3-triazol-4-yl)aniline 1c) which were formed by the copper(I)-catalyzed Huisgen[3+2] dipolar cycloaddition between 2-ethynylaniline and the corresponding azides in high yields, using anhydrous ZnCl(2) as the metal template, in boiling glacial acetic acid. Zinc complexes of the type [ZnCl(ArN=C(An)-C(An)=NAr)](+)[ZnCl(3)(NCCH(3))](-) (4a-c) were synthesized by crystallisation of the corresponding complexes 2a-c in acetonitrile, at -20 °C. After removal of zinc dichloride from complexes 2a-c by the addition of potassium oxalate, in dichloromethane, the tetradentate N,N,N,N-chelating α-diimine ligands of the type ArN=C(An)-C(An)=NAr (5a-c) were obtained. The new ligand precursors and zinc complexes were characterised by elemental analysis, (1)H and (13)C{(1)H} NMR spectroscopy, two-dimensional NMR spectroscopy, and X-ray diffraction. Reaction of the ligand precursors 5a-c with [NiBr(2)(DME)], in dichloromethane, gave nickel complexes of the type [NiBr(2)(ArN=C(An)-C(An)=NAr)] (6a-c). The results of single crystal X-ray diffraction characterisation and magnetic susceptibility measurements demonstrated that nickel complexes 6a-c possess octahedral geometries around the nickel atoms with variable configurations, the Br atoms of which can be ionized when dissolved in methanol. In preliminary catalytic tests, complexes 6a-c revealed to be active as catalysts for the polymerisation of norbornene and styrene, when activated by cocatalyst MAO. The characterisation of the polymers by (1)H and (13)C{(1)H} NMR spectroscopy, gel permeation chromatography/size-exclusion chromatography (GPC/SEC) revealed that these polymers were formed by a coordination addition mechanism., (© The Royal Society of Chemistry 2011)
- Published
- 2011
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41. Sodium complexes containing 2-iminopyrrolyl ligands: the influence of steric hindrance in the formation of coordination polymers.
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Gomes CS, Suresh D, Gomes PT, Veiros LF, Duarte MT, Nunes TG, and Oliveira MC
- Abstract
Iminopyrrolyl complexes of sodium were prepared from the reaction of 2-arylformiminopyrrole ligand precursors (aryl = C(6)H(5) (I); 2,6-Me(2)C(6)H(3) (II); 2,4,6-Me(3)C(6)H(2) (III); 2,6-(i)Pr(2)C(6)H(3) (IV)) with one equivalent of sodium hydride. The resulting corresponding compounds 1-4, [{Na(mu(2):kappa(2)N,N'-iminopyrrolyl)}(2n)(OEt(2))(2x)] (n > or = 1; x = 0 or 1), were obtained in moderate to high yields and were characterised by NMR spectroscopy, high resolution mass spectrometry and X-ray diffraction, when suitable crystals were obtained. The X-ray structure of compound 1 (n >> 1; x = 0) reveals the formation of a coordination polymer with repeating units consisting of dimers that contain two iminopyrrolyl ligands chelating two sodium atoms, where both pyrrolyl rings exhibit bridging sigma + sigma coordination to the Na atoms within the dimer; the self-assembling of the polymer is established by additional pi-bonds (eta(5)-coordination) of each of the pyrrolyl rings to the sodium atoms of the adjacent dimer units. Conversely, the structure of complex D(IV) (n = x = 1) shows it as one of such dimers capped by two diethyl ether molecules, each coordinated to the sodium atoms (n = 2; x = 1). DFT calculations indicate that the differences between the structures 1-4 of arise from the increasing bulkiness imposed by the corresponding substituents of the iminic aryl groups.
- Published
- 2010
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42. Compatibility of interspecific Manihot crosses presaged by protein electrophoresis .
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Nassar NM, Bomfim N, Chaib A, Abreu LF, and Gomes PT
- Subjects
- Electrophoresis, Genes, Plant, Genetic Markers, Crosses, Genetic, Hybridization, Genetic, Manihot genetics, Plant Proteins analysis
- Abstract
Cross incompatibility of wild Manihot species with cassava (M. esculenta) can impede their utilization for improving this cultigen. We tested whether compatibility could be determined based on electrophoresis results. Manihot pilosa, M. glaziovii, M. reptans, and M. cearulescens were tested. These species were allowed to hybridize with cassava to determine whether hybridization coincides with the similarity index based on electrophoresis analysis. Gene markers of leaf shape, stem surface, disk color, and fruit shape were used to confirm hybridization. Manihot pilosa and M. glaziovii successfully hybridized with cassava, while the others failed to do so under natural conditions. This result coincided with the similarity index from electrophoresis.
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- 2010
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43. Synthesis, structure, and photophysical characterization of blue-green luminescent zinc complexes containing 2-iminophenanthropyrrolyl ligands.
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Gomes CS, Gomes PT, Duarte MT, Di Paolo RE, Maçanita AL, and Calhorda MJ
- Subjects
- Crystallography, X-Ray, Ligands, Models, Molecular, Molecular Structure, Photochemistry, Luminescence, Organometallic Compounds chemistry, Pyrroles chemistry, Zinc chemistry
- Abstract
New 2-iminophenanthro[9,10-c]pyrrole ligand precursors containing phenyl or 2,6-diisopropylphenyl groups at the imine nitrogen substituent, 2-arylformiminophenanthro[9,10-c]pyrroles (aryl = phenyl IIa, 2,6-diisopropylphenyl IIb) were synthesized and deprotonated in situ with NaH, originating solutions of the corresponding sodium salts (IVa, IVb). The reaction of these salts with zinc chloride gave the homoleptic bis-ligand Zn(II) complexes [Zn(kappa(2)N,N'-2-arylformiminophenanthro[9,10-c]pyrrolyl)(2)] (aryl = phenyl 2a, 2,6-diisopropylphenyl 2b). The new ligand precursors and complexes were characterized by NMR, elemental analysis, UV/vis spectroscopy, and X-ray crystallography, when possible. The photophysical characterization was carried out using steady-state and picosecond time-resolved luminescence techniques in solution. The influence of the pi-extended conjugation of the condensed phenanthro group on the deprotonated iminopyrrolyl ligands coordinated to Zn(2+) greatly enhances fluorescence quantum yields of the complexes (2a, 2b) in relation to those of their ligand precursors (IIa, IIb). Complex 2a shows emission in the green spectral region (lambda(max) = 494 nm), presenting the highest fluorescence quantum yield (phi(f) = 8.8%). In the case of the complex 2b (phi(f) = 3.9%), the bulkiness of the 2,6-diisopropyl substituents of the arylimino group highly restricts the aryl ring rotation toward coplanarity with the ligand framework, inducing a shift in the emission to the blue region (lambda(max) = 459 nm). The values of the radiative (k(f)) and radiationless rate constants (k(nr)) show that the fluorescence quantum yield enhancement in the complexes results from a 50-fold increase in k(f) values, indicating much more allowed pi-pi* transitions in complexes 2a and 2b than those occurring in the ligand precursors IIa and IIb, with an essentially n-pi* character. These assignments were confirmed by density-functional theory (DFT) and time-dependent DFT (TD-DFT) molecular orbital calculations. Simple 2-aryliminopyrrole ligand precursors (Ia, Ib) and their Zn(II) complexes (1a, 1b) were also prepared to compare their photophysical properties with those of the corresponding 2-aryliminophenanthro[9,10-c]pyrrolyl compounds.
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- 2009
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44. Cytogenetic and molecular analysis of an apomictic cassava hybrid and its progeny.
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Nassar NM, Gomes PT, Chaib AM, Bomfim NN, Batista RC, and Collevatti RG
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- Electrophoresis, Polyacrylamide Gel, Genes, Plant, Microsatellite Repeats genetics, Manihot genetics
- Abstract
An interspecific hybrid between cassava and Manihot glaziovii acquired an apomixis gene from the parent M. glaziovii. This hybrid was exposed to open pollination during three subsequent generations. Seven sibs and the maternal progenitor of the fourth generation were genotyped using six microsatellite loci previously developed for cassava. All sibs were identical with each other and with their maternal progenitor. Sibs of selfed M. glaziovii proved to be identical when examined with these microsatellite loci. The chromosome complement of the apomictic clone was 2n = 38. We observed multi-embryonic aposporic embryo sacs.
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- 2009
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45. trans-Chlorido(phenyl)bis(triphenylphosphine)nickel(II) and its 1:1 cocrystal with chloridobis(triphenylphosphine)nickel(I).
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Li L, Gomes CS, Figueira CA, Gomes PT, and Duarte MT
- Abstract
Two conformational polymorphs of trans-chlorido(phenyl)bis(triphenylphosphine)nickel(II), [Ni(C(6)H(5))Cl(C(18)H(15)P)(2)], (1), viz. orange needle-shaped crystals (form I) and brown prism-shaped crystals (form II), were obtained under different crystallization conditions from a mixture of toluene and n-hexane, and characterized by single-crystal X-ray diffraction at low temperature. These two forms were compared with that published previously [Zeller, Herdtweck & Strassner (2003). Eur. J. Inorg. Chem. pp. 1802-1806], characterized at room temperature. Additionally, blue-green prisms of a 1:1 cocrystal of complex (1) with chloridobis(triphenylphosphine)nickel(I), (2), viz. trans-chlorido(phenyl)bis(triphenylphosphine)nickel(II)-chloridobis(triphenylphosphine)nickel(I) (1/1), [Ni(C(6)H(5))Cl(C(18)H(15)P)(2)].[NiCl(C(18)H(15)P)(2)], (3), were obtained concomitantly with form I. In forms I and II, as well as in the cocrystal, the overall crystal packings are determined by an energetic interplay between intramolecular torsions and weak intermolecular C-H...pi and C-H...Cl interactions.
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- 2009
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46. Synthesis, structure and magnetic behavior of five-coordinate bis(iminopyrrolyl) complexes of cobalt(II) containing PMe3 and THF ligands.
- Author
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Carabineiro SA, Bellabarba RM, Gomes PT, Pascu SI, Veiros LF, Freire C, Pereira LC, Henriques RT, Oliveira MC, and Warren JE
- Abstract
The new bis-iminopyrrolyl five-coordinate Co(II) complexes [Co(kappa (2) N, N'-NC 4H 3C(R)N-2,6- (i)Pr 2C 6H 3) 2(PMe 3)] (R = H 3a; Me 3b) were synthesized in high yields (ca. 80-90%), using THF and diethyl ether as solvents, respectively, by (a) treatment of CoCl 2(PMe 3) 2 with the corresponding iminopyrrolyl Na salts ( Ie or If) or (b) reaction of anhydrous CoCl 2 and PMe 3 with Ie or If. A third route was tested, involving the addition of excesses of PMe 3 to the complexes [Co(kappa (2) N, N'-NC 4H 3C(R)N-2,6- (i)Pr 2C 6H 3) 2] (R = H 1e; Me 1f), which was only successful for the synthesis of 3a, in lower yields (ca. 30%). The synthesis of 3b in THF was unfruitful because of the kinetic competition of the solvent, giving rise to mixtures of 1f and its coordinated THF adduct 4b. The synthesis of the new bis-iminopyrrolyl five-coordinate Co(II) complexes [Co(kappa (2) N, N'-NC 4H 3C(R)N-2,6- (i)Pr 2C 6H 3) 2(THF)] (R = H 4a; Me 4b) were carried out in high yields (ca. 80-90%) by the reaction of CoCl 2(THF) 1.5 with the corresponding iminopyrrolyl Na salt. All the compounds have been characterized by X-ray diffraction, with 3a and 3b showing axially compressed trigonal bipyramidal geometry (with the PMe 3 ligand lying on the equatorial plane), whereas complexes 4a and 4b exhibit distorted square pyramidal geometries with the THF molecule occupying the axial position. Complex 4a shows clearly a compressed geometry, but for complex 4b, two polymorphs were characterized, exhibiting molecules with different Co-O (THF) bond lengths, one of them being compatible with an elongated form. Magnetic measurements either in the solid or in the liquid phases indicate that complexes 3a and 3b have low-spin ground states ( S = 1/2). In toluene solution, the geometry is fully confirmed by EPR data, which further indicates a d x (2) - y (2) /d xy ground state. However, compounds 4a and 4b behave unusually because they show magnetic moments that are compatible with high-spin ground states ( S = 3/2) in the solid state, but conform to low-spin ground states ( S = 1/2) when both complexes are dissolved in toluene solutions. The low-spin ground states in toluene solution are confirmed by EPR spectroscopy, which further supports, for complexes 4a and 4b, an axially elongated square pyramidal geometry and a d z (2) ground state. Thus the change in the ground-state and, consequently, in the geometry of complexes 4a and 4b from solid state to toluene solution might be a consequence of the elongation of the Co-O(THF) bond length. DFT studies performed on complexes 3 and 4 corroborate their different structure and magnetic behaviors and verify, for the latter complexes, the structural differences observed in the solid state and in toluene solution.
- Published
- 2008
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47. 5-phenyl-3,4-dihydro-2H-pyrrole: the first example of a planar monosubstituted 1-pyrroline.
- Author
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Gomes CS, Figueira CA, Gomes PT, and Duarte MT
- Subjects
- Dimerization, Molecular Conformation, Molecular Structure, X-Ray Diffraction, Pyrroles chemistry
- Abstract
In the title compound, C10H11N, the molecules assemble as pseudo-dimers through pi-pi interactions, each dimer being rotated by about 90 degrees with respect to its neighbours. The relative positioning of the dimers and C-H...pi interactions give, when seen along a, a supramolecular zigzag arrangement. The compound contains a planar pyrroline ring and, as a whole, its molecular conformation is also planar, which represents the first example of a totally planar 2-substituted 1-pyrroline and the simplest ever reported by X-ray diffraction.
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- 2008
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48. Bis(ketopyrrolyl) complexes of Co(II) stabilised by trimethylphosphine ligands.
- Author
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Carabineiro SA, Gomes PT, Veiros LF, Freire C, Pereira LC, Henriques RT, Warren JE, and Pascu SI
- Abstract
2-Formylpyrrole and 2-acetylpyrrole were deprotonated with NaH to give the corresponding Na salts 1a and 1b, respectively. The reactivity of these salts towards cobalt chloride compounds was studied. The resulting new bis(ketopyrrolyl) Co(II) 19-electron complexes [Co(kappa(2)N,O-2-NC4H3C(R)=O)2(PMe3)2] (R = H 2a, and Me 2b) were characterised by single crystal X-ray diffraction, to show an octahedral geometry with the PMe3 ligands in trans positions to each other, and two bidentate ketopyrrolyl ligands occupying the remaining coordination positions in a transoid conformation. Powder and solution magnetic susceptibility measurements together with EPR and UV/Vis/NIR spectra revealed a low-spin ground state (dz2, S = 1/2) for Co(II) in these compounds. Analysis of the EPR superhyperfine couplings suggested that the longer distances (z axis) of the hexacoordinate Co coordination sphere are occupied by the keto-O atoms of the bidentate ligand, leaving the pyrrolyl N and the phosphine P atoms within the equatorial plane. This is confirmed by means of DFT calculations, which also indicate that the most thermodynamically stable isomers are low-spin (S = 1/2) complexes with coordination geometries corresponding to the molecular structures obtained by X-ray crystallography.
- Published
- 2007
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49. Synthesis and characterization of tetrahedral and square planar Bis(iminopyrrolyl) complexes of cobalt(II).
- Author
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Carabineiro SA, Silva LC, Gomes PT, Pereira LC, Veiros LF, Pascu SI, Duarte MT, Namorado S, and Henriques RT
- Abstract
A series of 2-iminopyrrole ligand precursors with increasing bulkiness [HNC4H3C(R)=N-2,6-R'2C6H3] (R = R' = H, 1a; R = Me, R'= H, 1b; R = H, R' = Me, 1c; R = R' = Me, 1d; R = H, R' = iPr, 1e; R = Me, R' = iPr, 1f) were synthesized and deprotonated with NaH to give the corresponding iminopyrrolyl sodium salts 2a-f. A set of homoleptic bis-ligand Co(II) complexes of the type [Co(kappa2N,N'-NC4H3C(R)=N-2,6-R'2C6H3)2] (R = R'= H, 3a; R = Me, R'= H, 3b; R = H, R' = Me, 3c; R = R' = Me, 3d; R = H, R' = iPr, 3e; R = Me, R' = iPr, 3f) was prepared by reaction of CoCl2 with the corresponding iminopyrrolyl sodium salts 2a-f. The new complexes were characterized by elemental analysis, magnetic susceptibility measurements, in powder and in solution, UV/vis/NIR, and, in some cases, X-ray crystallography. According to X-ray diffraction and magnetic measurements, the Co complexes 3a-e proved to be tetrahedral, which is the preferred geometry for Co(II) compounds. However, a square planar geometry is observed in the case of 3f, as determined by several characterization techniques. In this case, DFT calculations suggest the square planar geometry is slightly more stable than the tetrahedral one probably due to a combination of steric and electronic reasons.
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- 2007
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50. Pulmonary alveolar proteinosis: four cases.
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Thompson JC, Kishima M, Gomes MU, Menezes Mde A, Perandré Neto J, and Pereira PT
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- Adult, Female, Humans, Male, Pulmonary Alveolar Proteinosis therapy, Retrospective Studies, Treatment Outcome, Bronchoalveolar Lavage methods, Pulmonary Alveolar Proteinosis diagnosis
- Abstract
Objective: The aim of this study was to present the evolution of four patients presenting pulmonary alveolar proteinosis and treated at the State University of Londrina School of Medicine. We focus on the importance of whole-lung lavage as the treatment of choice., Methods: A retrospective study of four patients, three females and one male, 22 to 34 years old, presenting similar histories of progressive dyspnea and dry cough. The final diagnosis was established through open-lung biopsy. Three of the patients underwent whole-lung lavage in the Department of Surgery. The procedures were performed under general anesthesia and using a double-lumen endotracheal tube., Results: One patient presented spontaneous regression of the pulmonary alveolar proteinosis without the need for whole-lung lavage. In the other three cases, the number of lavages varied: in one patient, a single unilateral lavage resulted in complete remission of the bilateral process; in another patient, three lavages yielded no significant improvement; in the remaining patient, four lavages provided intervening periods of transient improvement., Conclusion: In the cases evaluated, whole-lung lavage proved an efficient treatment for pulmonary alveolar proteinosis. Although some patients presented a certain resistance to the procedure, it might lead to complete remission of the disease in others.
- Published
- 2006
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