21 results on '"Paula María de Carvalho Pinto Costa"'
Search Results
2. Light driven PVDF fibers based on photochromic nanosilica@naphthopyran fabricated by wet spinning
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Céu M. Sousa, Tânia V. Pinto, Clara Pereira, Paula María de Carvalho Pinto Costa, Nelson Cardoso, Carla J. S. M. Silva, Cristina Freire, Nelson F. Durães, and Paulo J. Coelho
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Materials science ,Scanning electron microscope ,Doping ,Energy-dispersive X-ray spectroscopy ,General Physics and Astronomy ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Polyvinylidene fluoride ,0104 chemical sciences ,Surfaces, Coatings and Films ,Nanomaterials ,Amorphous solid ,Photochromism ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,0210 nano-technology ,Spinning - Abstract
Photoresponsive polyvinylidene fluoride (PVDF) fibers doped with naphthopyran-functionalized silica nanoparticles (SiO2@NPT) were successfully prepared by dry–jet wet spinning. The incorporated photochromic nanomaterials, SiO2@S1 and SiO2@S2, were previously prepared by covalent post-grafting of the silylated NPTs – 2H-naphtho[1,2-b]pyran derivatives, S1 and S2 – onto nano-sized SiO2 (15 ± 3 nm). The morphological and chemical characterization of the resulting doped fibers PVDF@SiO2@S1 and PVDF@SiO2@S2 was evaluated by scanning electron microscopy with energy dispersive spectroscopy and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Both PVDF@SiO2@S1 and PVDF@SiO2@S2 fibers presented average diameters of 133 ± 8 μm and 98 ± 7 μm, respectively, and a porous outer surface. The presence of the SiO2@NPT within the fibers was confirmed through the observation of dense clusters embedded within the polymeric matrix. Furthermore, the FTIR-ATR spectra of the fibers revealed that the PVDF matrix was composed of α and β crystalline and amorphous phases. The PVDF@SiO2@S1 and PVDF@SiO2@S2 fibers showed photoresponsive properties under UV and sunlight irradiation, exhibiting fast coloration kinetics and good optical contrast (ΔE*ab = 7.2 and 15.1, respectively), and changing from a pale orange and an off-white color to a more intense yellow-orange and purple coloration, respectively, in less than 1 min. Moreover, they showed an initial fast bleaching, losing half of their color in less than 30 min (t1/2 = 28 and 20 min for PVDF@SiO2@S1 and PVDF@SiO2@S2 fibers, respectively), but displaying a residual coloration that took 1 and 2 h to return to the initial uncolored state (t3/4 = 95 and 49 min, respectively). The PVDF@SiO2@S2 fibers presented the best photochromic performance. more...
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- 2019
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Catalog
3. Acid functionalized coal fly ashes: New solid catalysts for levulinic acid esterification
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Bruno Valentim, Ana Cláudia Santos, Andreia F. Peixoto, Sónia M. Silva, Cristina Freire, Paula María de Carvalho Pinto Costa, and Juan Manuel Lázaro-Martínez
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ESTERIFICATION ,Físico-Química, Ciencia de los Polímeros, Electroquímica ,02 engineering and technology ,010402 general chemistry ,complex mixtures ,01 natural sciences ,Catalysis ,chemistry.chemical_compound ,LEVULINIC ACID ,COAL FLY ASH ,Levulinic acid ,Size fractions ,SOLID ACID CATALYST ,Coal ,business.industry ,fungi ,technology, industry, and agriculture ,Ciencias Químicas ,General Chemistry ,respiratory system ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,Fly ash ,N-BUTYL LEVULINATE ,0210 nano-technology ,business ,CIENCIAS NATURALES Y EXACTAS ,Nuclear chemistry - Abstract
Coal fly ash (CFA) from different sources (CFA 5, 10, 13) and different size fractions (> or < 75 μm) were characterized and used as inorganic supports for sulfonic acid functionalization by two methodologies including one-pot organosilylation (CFA_CSPTMS) and two-step benzyl alcohol condensation followed by sulfonation (CFA_BnSO3H). The as-prepared organosulfonic CFAs were characterized by solid-state 1H, 13C and 29Si NMR spectroscopy, XPS, S content was quantified by elemental analysis and the intrinsic acidity was determined by potentiometric titration; the highest –SO3H content was obtained for CFA13_BnSO3H. All the functionalized CFAs were tested for the first time as acid solid catalysts in the esterification of levulinic acid (LA) a biomass platform molecule, in the presence of n-butanol. n-Butyl levulinate was the only product with conversions of 100% after 40 min. reaction and using the CFA13_BnSO3H as catalyst. This catalyst also exhibited the highest TOFs (447 h−1) and showed to be the most stable and reusable for 5 consecutive catalytic cycles. Fil: Peixoto, Andreia F.. Universidad de Porto; Portugal Fil: Silva, Sónia M.. No especifíca; Fil: Costa, Paula. No especifíca; Fil: Santos, Ana Claúdia. Universidad de Porto; Portugal Fil: Valentim, Bruno. Universidad de Porto; Portugal Fil: Lazaro Martinez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; Argentina Fil: Freire, Cristina. Universidad de Porto; Portugal more...
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- 2020
4. l-serine-functionalized montmorillonite decorated with Au nanoparticles: A new highly efficient catalyst for the reduction of 4-nitrophenol
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José E. Rodríguez-Borges, Mariana Rocha, Paula María de Carvalho Pinto Costa, Carlos Sousa, Cristina Freire, and Clara Pereira
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Chemistry ,Reducing agent ,Nanoparticle ,4-Nitrophenol ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Catalysis ,0104 chemical sciences ,chemistry.chemical_compound ,Montmorillonite ,Reaction rate constant ,Colloidal gold ,Leaching (metallurgy) ,Physical and Theoretical Chemistry ,0210 nano-technology ,Nuclear chemistry - Abstract
The conversion of nitroarenes to aminoarenes is of great industrial interest since they are prevalent pollutants in water and aminoarenes are important intermediates in the synthesis of pharmaceuticals, natural products and in bulk chemical production. In this work, two new catalysts for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) were prepared by immobilization of gold nanoparticles onto the surface of K10 montmorillonite clay (K10) functionalized with two new l -serine derivative organosilanes. Transmission electron microscopy showed the presence of 4–5 nm gold nanoparticles after catalysis. The reduction reaction of 4-NP to 4-AP at 25 °C, using NaBH4 as reducing agent, led to nearly 100% conversion in only 1 minute, presenting pseudo-first-order rate constants normalized for Au loading of K = 630 and 430 mmol−1 s−1. The catalysts showed high stability, leading to substrate conversions of 95–100% after 10 consecutive cycles, with negligible Au leaching. more...
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- 2018
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5. Robust Mesoporous CoMo/γ-Al2O3 Catalysts from Cyclodextrin-Based Supramolecular Assemblies for Hydrothermal Processing of Microalgae: Effect of the Preparation Method
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Anne Ponchel, Rudina Bleta, Benedetto Schiavo, Salvatore Sau, Paula María de Carvalho Pinto Costa, Leonardo Interrante, Onofrio Scialdone, Sébastien Tilloy, Eric Monflier, Natale Corsaro, Alberto Giaconia, Giuseppe Pipitone, Alessandro Galia, Bleta, Rudina, Schiavo, Benedetto, Corsaro, Natale, Costa, Paula, Giaconia, Alberto, Interrante, Leonardo, Monflier, Eric, Pipitone, Giuseppe, Ponchel, Anne, Sau, Salvatore, Scialdone, Onofrio, Tilloy, Sébastien, Galia, Alessandro, Giaconia, A., Corsaro, N., UCCS Équipe Catalyse Supramoléculaire, Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille-Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Università di Palermo - viale delle Scienze, Laboratório Nacional de Energia e Geologia (LNEG), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Università degli studi di Palermo - University of Palermo more...
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Materials science ,02 engineering and technology ,010402 general chemistry ,biocrude ,01 natural sciences ,Hydrothermal circulation ,Catalysis ,Copolymer ,[CHIM]Chemical Sciences ,General Materials Science ,ComputingMilieux_MISCELLANEOUS ,cyclodextrin ,heterogeneous catalysts ,hydrothermal liquefaction ,microalgae ,heterogeneous catalyst ,Aqueous two-phase system ,[CHIM.CATA]Chemical Sciences/Catalysis ,Settore ING-IND/27 - Chimica Industriale E Tecnologica ,021001 nanoscience & nanotechnology ,Biorefinery ,0104 chemical sciences ,Hydrothermal liquefaction ,Chemical engineering ,Yield (chemistry) ,Materials Science (all) ,0210 nano-technology ,Mesoporous material - Abstract
Hydrothermal liquefaction (HTL) is a promising technology for the production of biocrude oil from microalgae. Although this catalyst-free technology is efficient under high-temperature and high-pressure conditions, the biocrude yield and quality can be further improved by using heterogeneous catalysts. The design of robust catalysts that preserve their performance under hydrothermal conditions will be therefore very important in the development of biorefinery technologies. In this work, we describe two different synthetic routes (i.e., impregnation and cyclodextrin-assisted one-pot colloidal approach), for the preparation in aqueous phase of six high surface area CoMo/γ-Al2O3 catalysts. Catalytic tests performed on the HTL of Nannochloropsis gaditana microalga indicate that solids prepared by the one-pot colloidal approach show higher hydrothermal stability and enhanced biocrude yield with respect to the catalyst-free test. The positive effect of the substitution of the block copolymer Tetronic T90R4 for Pluronic F127 in the preparation procedure was evidenced by diffuse reflectance UV-visible spectroscopy, X-ray diffraction, N2-adsorption-desorption, and H2-temperature-programmed reduction measurements and confirmed by the higher quality of the obtained biocrude, which exhibited lower oxygen content and higher-energy recovery equal to 62.5% of the initial biomass. © 2018 American Chemical Society. more...
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- 2018
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6. Exophiala Keratitis following Descemet Stripping Automated Endothelial Keratoplasty
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Ana Marta, Paula María de Carvalho Pinto Costa, Virgínia M. Lopes, Miguel Gomes, Miguel Mesquita Neves, and Luis Oliveira
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0303 health sciences ,medicine.medical_specialty ,biology ,genetic structures ,030306 microbiology ,business.industry ,Case Report ,General Medicine ,RE1-994 ,Descemet stripping automated endothelial keratoplasty ,biology.organism_classification ,medicine.disease ,eye diseases ,Keratitis ,03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,Exophiala ,030221 ophthalmology & optometry ,medicine ,Fungal keratitis ,sense organs ,business ,Pseudophakic bullous keratopathy - Abstract
Purpose: To report a case with Exophiala spp. keratitis in a Portuguese patient. Methods: A case report with deep corneal brown-pigmented infiltrates that developed 2 months after a Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) for pseudophakic bullous keratopathy. Results: Diagnosis was established by positive direct examination and cultures from the surgically obtained corneal button. Slit-lamp images and anterior segment optical coherence tomography (AS-OCT) scans were obtained. Conclusion: This is the first described case of fungal keratitis caused by Exophiala spp. in Portugal and, to our knowledge, the first case following DSAEK in the literature. info:eu-repo/semantics/publishedVersion more...
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- 2020
7. Screen-Printed Photochromic Textiles through New Inks Based on SiO2@naphthopyran Nanoparticles
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Clara Pereira, Paulo J. Coelho, Tânia V. Pinto, Carla Silva, Manuel Fernando R. Pereira, Carlos Sousa, Paula María de Carvalho Pinto Costa, Céu M. Sousa, and Cristina Freire
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Aqueous solution ,Materials science ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Photochromism ,Adsorption ,chemistry ,Covalent bond ,Pyran ,Screen printing ,General Materials Science ,Composite material ,0210 nano-technology ,Polyurethane - Abstract
Photochromic silica nanoparticles (SiO2@NPT), fabricated through the covalent immobilization of silylated naphthopyrans (NPTs) based on 2H-naphtho[1,2-b]pyran (S1, S2) and 3H-naphtho[2,1-b]pyran (S3, S4) or through the direct adsorption of the parent naphthopyrans (1, 3) onto silica nanoparticles (SiO2 NPs), were successfully incorporated onto cotton fabrics by a screen-printing process. Two aqueous acrylic- (AC-) and polyurethane- (PU-) based inks were used as dispersing media. All textiles exhibited reversible photochromism under UV and solar irradiation, developing fast responses and intense coloration. The fabrics coated with SiO2@S1 and SiO2@S2 showed rapid color changes and high contrasts (ΔE*ab = 39–52), despite presenting slower bleaching kinetics (2–3 h to fade to the original color), whereas the textiles coated with SiO2@S3 and SiO2@S4 exhibited excellent engagement between coloration and decoloration rates (coloration and fading times of 1 and 2 min, respectively; ΔE*ab = 27–53). The PU-based f... more...
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- 2016
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8. Military Orders Between Territorialization and Periphery from the 12th to the 16th Century
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Cristina Pimenta, Luis Adao da Fonseca, Paula María de Carvalho Pinto Costa, and Kurt Villads Jensen
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History ,Alterity ,05 social sciences ,06 humanities and the arts ,Ancient history ,0506 political science ,060104 history ,Medieval history ,050602 political science & public administration ,Western world ,Military history ,Ethnology ,0601 history and archaeology ,Middle Ages ,Comparative perspective - Abstract
Military orders have historically played a key role in defining borders, both in a mental sense, by favouring an awareness of alterity in the most peripheral territories (Christians against Muslims and Christians against Pagans), and also in more direct ways, as owners of land in these territories. This article1 discusses both the influence, in the broadest sense, of territory and periphery upon the medieval military orders, and the relationship between the crown and the military orders. It will be done through a comparative historical analysis of two cases: Portugal and Denmark in the 12th–16th centuries. Both countries were placed at the periphery of the Western world in the Middle Ages, and they were both active agents in the Crusading movement. more...
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- 2016
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9. Highly active organosulfonic aryl-silica nanoparticles as efficient catalysts for biomass derived biodiesel and fuel additives
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Cristina Freire, Paula María de Carvalho Pinto Costa, Sónia M. Silva, Tânia V. Pinto, Andreia F. Peixoto, Elisabete C. B. A. Alegria, and Mohamed M. A. Soliman
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Biodiesel ,Renewable Energy, Sustainability and the Environment ,020209 energy ,Aryl ,Forestry ,02 engineering and technology ,Furfural ,Catalysis ,chemistry.chemical_compound ,chemistry ,Yield (chemistry) ,0202 electrical engineering, electronic engineering, information engineering ,Levulinic acid ,Organic chemistry ,Aldol condensation ,Selectivity ,Waste Management and Disposal ,Agronomy and Crop Science - Abstract
Post-grafting methodologies were used to prepare aryl-organosulfonic acid functionalized silica nanoparticles (SO3H-aryl-SiO2NPs) as highly active heterogeneous acid catalysts for catalytic esterification of free fatty acids (FFA) and levulinic acid (LA), and aldol condensation of furfural with 3-methylfuran, well known renewable feedstocks for biodiesel and fuel additives production. The chemical and structural characterization of the SO3H-aryl-SiO2NPs confirmed the success of the functionalization. Complete conversion for all FFA was observed using SO3H-aryl-SiO2NPs after 2 h of reaction. SiO2NPs_CSPTMS showed to be the most active and stable catalyst with no significant loss of activity in the first 5 cycles. In the LA esterification in the presence of an alcohol, complete conversion and selectivity and high reusability were observed (e.g., 83.2% yield after 10 cycles in the presence of 1-propanol, SiO2NPs10_CSPTMS, at 120 °C and 2h reaction). Finally, aldol condensation of furfural and 3-methylfuran had been performed using SiO2NPs_CSPTMS catalysts with almost 100% yield after 10 min at 65 °C, high stability and reusability for 7 catalytic cycles. In general, the prepared SO3H-aryl-SiO2NPs have demonstrated promising catalytic performance for transformation of biomass-derived feedstocks into biodiesel and fuel additives. more...
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- 2021
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10. Session 19: Psychology and counselling
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Albert Wolthuis, André D'Hoore, Ignace Vergote, Aleida G. Huppelschoten, Susan Golombok, L. Bastings, Susan Imrie, I.C.P. Philipse, Carla Tomassetti, U. Van den Broeck, A.J.C.M. van Dongen, Lone Schmidt, Paula María de Carvalho Pinto Costa, B. Van Cleynenbreugel, Maria Emília Costa, Jan A.M. Kremer, Chris M. Verhaak, Paul Enzlin, Christianne M. Verhaak, Thomas D'Hooghe, Maria Manuela Ferreira Pereira da Silva Martins, Carl J.C.M. Hamilton, Freddy Penninckx, Jesper M. J. Smeenk, Willianne L.D.M. Nelen, Brennan D. Peterson, Christel Meuleman, V. Jadva, and Didi D.M. Braat more...
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Psychotherapist ,Reproductive Medicine ,Rehabilitation ,Obstetrics and Gynecology ,Session (computer science) ,Psychology - Published
- 2013
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11. The Knights of Marmelar
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Maria Cristina Pimenta and Paula María de Carvalho Pinto Costa
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History ,Pilgrimage ,Ancient history - Published
- 2016
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12. A cruzada e os objectivos fundacionais das Ordens Religioso-Militares em Portugal
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Paula María de Carvalho Pinto Costa and Maria Cristina Pimenta
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History ,Political science - Published
- 2009
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13. Identification of new breakpoints in AZFb and AZFc
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Mário Sousa, Paula María de Carvalho Pinto Costa, Rita Gonçalves, Susana Fernandes, Alberto Barros, Ana Teresa Fernandes, and Cristina Ferrás
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Adult ,Male ,Embryology ,Sequence analysis ,Molecular Sequence Data ,Biology ,Y chromosome ,Polymerase Chain Reaction ,Haplogroup ,Sequence-tagged site ,Genetics ,medicine ,Humans ,Molecular Biology ,Sequence Tagged Sites ,Recombination, Genetic ,Chromosomes, Human, Y ,Base Sequence ,Haplotype ,Breakpoint ,Obstetrics and Gynecology ,Chromosome Breakage ,Sequence Analysis, DNA ,Cell Biology ,medicine.disease ,Molecular biology ,Haplotypes ,Reproductive Medicine ,Oligospermia ,Chromosome Deletion ,Chromosome breakage ,Developmental Biology - Abstract
Microdeletions in AZFa, AZFb and AZFc regions lead to different patterns of male infertility, from severe oligozoospermia to non-obstructive azoospermia. Intrachromosomal homologous recombination mechanisms were already identified in patients with simultaneous microdeletions in the AZFb and AZFc regions. Ten patients with atypical AZFb and AZFc deletion patterns were studied. The definition of those microdeletions and the fine characterization of the respective breakpoints were performed using sequence tagged sites/single nucleotide variants-PCR and DNA sequencing. Y-chromosome haplogroups were determined to establish a putative association with the patterns obtained. Seven deletion patterns were identified, P5/terminal (30%; 3/10), P5/P1 distal (20%; 2/10), IR4/distal-P2, IR2/proximal-P1, IR4/distal-P1, P4/terminal and complete AZFb/c deletion (10%; 1/10). Breakpoint sequence analysis suggests that only in one patient the P5/P1 distal deletion pattern was due to a homologous recombination mechanism. Sequence alignment of the other deletion patterns suggest that they have resulted from non-homologous recombination mechanisms. more...
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- 2008
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14. Naphthopyran-Based Silica Nanoparticles as New High-Performance Photoresponsive Materials
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Tânia V. Pinto, Carla S. M. Silva, Manuel Fernando R. Pereira, Paulo J. Coelho, Cristina Freire, Carlos Sousa, Céu M. Sousa, Olívia S. G. P. Soares, Clara Pereira, Andreia Sofia De Sousa Monteiro, Paula María de Carvalho Pinto Costa, Faculdade de Engenharia, and Faculdade de Ciências more...
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Materials science ,Silylation ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Grafting ,01 natural sciences ,Isocyanate ,Combinatorial chemistry ,0104 chemical sciences ,Nanomaterials ,Photochromism ,chemistry.chemical_compound ,Adsorption ,chemistry ,Covalent bond ,Pyran ,Organic chemistry ,General Materials Science ,0210 nano-technology - Abstract
Hybrid nanomaterials based on the covalent of silylated naphthopyrans (NPTs) onto silica nanoparticles (SiO2 NPs) were successfully prepared and studied as new photochromic materials. They were prepared by a two-step protocol consisting of (i) NPTs (derivatives from 2H-naphtho[1,2-b]pyran (2H-NPT) and 3H-naphtho-[2,1-b]pyran (3H-NPT)) silylation by a microwave-assisted reaction between hydroxyl-substituted NPTs and 3(triethoxysilyl)propyl isocyanate, followed by (ii) covalent post-grafting onto SiO2 NPs. In order to study the role-of the silylation step, the analogous non-silylated nanomaterials were also prepared by direct adsorption of NPTs. The characterization techniques confirmed the successful NPTs silylation and subsequent grafting to SiO2 NPs. All SiO2-based nanomaterials revealed photoswitching behavior, following a biexponential decay. The SiO2 NPs functionalized with silylated 3H-NPTs (SiO2@S3 and SiO2@S4) presented the most promising photochromic properties, showing fast coloration/decoloration kinetics (coloring in 1 min under UV irradiation and fading in only 2 min) and high values of total color difference (Delta E-ab* = 30-50). Also, the 2H-NPTs-based SiO2 NPs (SiO2@S1 and SiO2@S2) presented fast coloration and good color contrasts (Delta E-ab* = 54); but slower fading kinetic rates, taking more than 2 h to return to their initial color. In contrast, the SiO2 NPs functionalized with non-silylated NPTs (SiO2@1 and SiO2@3) showed weaker color contrasts (Delta E-ab* = 6-10) and slower fading kinetics, proving that the NPT silylation step was crucial to enhance the photochromic behavior of SiO2 NPs based on NPTs. Furthermore, the silylated-based nanomaterials showed good photostability upon prolonged UV light exposure) keeping their photochromic performance unchanged for at least 12 successive UV/dark cycles, anticipating interesting technological applications in several areas. more...
- Published
- 2016
15. DAZ gene copies: evidence of Y chromosome evolution
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Paula María de Carvalho Pinto Costa, Rita Gonçalves, António Brehm, Alberto Barros, Cristina Ferrás, Ana Teresa Fernandes, Susana Fernandes, Alexandra Rosa, Rosália Sá, and Mário Sousa
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Male ,Embryology ,Mutation rate ,Gene Dosage ,Biology ,Y chromosome ,Polymorphism, Single Nucleotide ,Haplogroup ,Evolution, Molecular ,Faculdade de Ciências da Vida ,Regulation of testis function ,Phylogenetics ,Genetics ,Humans ,SNP ,Molecular Biology ,Gene ,Infertility, Male ,Phylogeny ,Chromosomes, Human, Y ,Models, Genetic ,Haplotype ,Seminal Plasma Proteins ,RNA-Binding Proteins ,Obstetrics and Gynecology ,Deleted in Azoospermia 1 Protein ,Cell Biology ,DAZ ,Haplotypes ,Reproductive Medicine ,Genetic Loci ,Mutation ,Microsatellite ,Infertile ,Chromosome Deletion ,Gene Deletion ,Developmental Biology - Abstract
The DAZ gene, a contributing factor in infertility, lies on the human Y chromosome's AZFc region, whose deletion is a common cause of spermatogenic failure. Y chromosome binary polymorphisms on the non-recombining Y (NRY) region, believed to be a single occurrence on an evolutionary scale, were typed in a sample of fertile and infertile men with known DAZ backgrounds. The Y single-nucleotide polymorphisms (Y-SNPs) with low mutation rates are currently well characterized and permit the construction of a unique phylogeny of haplogroups. DAZ haplotypes were defined using single-nucleotide variant (SNV)/sequence tagged-site (STS) markers to distinguish between the four copies of the gene. The variation of 10 Y chromosome short tandem repeat (STRs) was used to determine the coalescence age of DAZ haplotypes in a comparable time frame similar to that of SNP haplogroups. An association between DAZ haplotypes and Y chromosome haplogroups was found, and our data show that the DAZ gene is not under selective constraints and its evolution depends only on the mutation rate. The same variants were common to fertile and infertile men, although partial DAZ deletions occurred only in infertile men, suggesting that those should only be used as a tool for infertility diagnosis when analysed in combination with haplogroup determinations. more...
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- 2006
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16. SESSION 64: PSYCHOLOGY AND COUNSELLING - CLINICAL ISSUES
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Mariana Martins, B. Börkan, Sofia Gameiro, S. Belen, L. Van Glabeke, Rita Vassena, Brennan D. Peterson, E. Cha, J.S. Byun, Rikke Lund, Oriol Coll, S. Han, Katrien Wierckx, Lone Schmidt, L. Peronace, Paula María de Carvalho Pinto Costa, Isabelle Stuyver, Z.H. Sart, W. Kramer, Valérie Vernaeve, O. Bautista, Jacky Boivin, C. Bak, Maria Emília Costa, P. De Sutter, L. Venereo, David García, Chris M. Verhaak, I. Ertüzün, Jan Gerris, E. Van den Abbeel, S.W. Lyu, Guy T'Sjoen, H.H. Seok, J.H. Lee, and T.K. Yoon more...
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Psychotherapist ,Reproductive Medicine ,Rehabilitation ,Obstetrics and Gynecology ,Session (computer science) ,Psychology - Published
- 2012
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17. De la frontière à la consolidation du territoire : la contribution des Ordres militaires au processus de territorialisation aux XIIe-XIIIe siècles
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Paula María de Carvalho Pinto Costa
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- 2015
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18. AZFb microdeletions and oligozoospermia--which mechanisms?
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Ana Soares, Paula María de Carvalho Pinto Costa, Alberto Barros, Susana Fernandes, Mário Sousa, and Joaquina Silva
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Adult ,Male ,Reproductive Techniques, Assisted ,Y chromosome microdeletion ,Sex Chromosome Disorders of Sex Development ,Chromosome Breakpoints ,Biology ,Y chromosome ,Polymerase Chain Reaction ,Polymorphism, Single Nucleotide ,Severity of Illness Index ,Sequence-tagged site ,Polymorphism (computer science) ,medicine ,Humans ,Genetic Predisposition to Disease ,Spermatogenesis ,Infertility, Male ,Sex Chromosome Aberrations ,Sequence Tagged Sites ,Azoospermia ,Genetics ,Recombination, Genetic ,Chromosomes, Human, Y ,Breakpoint ,Obstetrics and Gynecology ,Karyotype ,Oligospermia ,Middle Aged ,medicine.disease ,Fertility ,Phenotype ,Treatment Outcome ,Reproductive Medicine ,Karyotyping ,Chromosome Deletion - Abstract
Objective To characterize the deletion patterns and its breakpoints in oligozoospermic patients presenting AZFb and AZFc microdeletions and to understand the recombination mechanisms underlying these microdeletions. Design Case report. Setting Genetics Department of Faculty of Medicine of Porto, Porto, Portugal. Patient(s) Two men with severe oligozoospermia and two men with nonobstructive azoospermia identified as having different AZFb+c deletion patterns via Y chromosome microdeletion analysis. Intervention(s) Definition of microdeletions and the fine characterization of the respective breakpoints by sequence-tagged sites (STS) polymerase chain reaction (PCR) and single-nucleotide variant (SNV) PCR. Main Outcome Measure(s) Study of the fine structure of the Y-chromosome and discussion of the putative mechanisms involved in each microdeletion pattern. Result(s) From the four patients studied, three deletion patterns were identified: IR4/distal-P2 (25%; 1 of 4), P5/proximal-P1 (50%; 2 of 4), and P5/distal-P1 (25%; 1 of 4). Although severe oligozoospermia is normally associated with AZFc, a complete AZFb deletion was found in one case. Conclusion(s) Analysis of these patients has revealed a new putative region that may be involved in spermatogenesis conservation. more...
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- 2011
19. Abnormal methylation of imprinted genes in human sperm is associated with oligozoospermia
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Susana Fernandes, Alberto Barros, Paula María de Carvalho Pinto Costa, Mário Sousa, Filipa Carvalho, B. Vaz, and C. J. Marques
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Male ,Embryology ,medicine.medical_specialty ,Reproductive technology ,Biology ,Male infertility ,Andrology ,Genomic Imprinting ,Internal medicine ,Genetics ,medicine ,Humans ,Imprinting (psychology) ,Molecular Biology ,Infertility, Male ,Obstetrics and Gynecology ,Cell Biology ,Methylation ,Oligospermia ,DNA Methylation ,medicine.disease ,Sperm ,Spermatozoa ,Endocrinology ,Reproductive Medicine ,DNA methylation ,Genomic imprinting ,Developmental Biology - Abstract
Genomic imprinting marks in the male germ line are already established in the adult germinal stem cell population. We studied the methylation patterns of H19 and MEST imprinted genes in sperm of control and oligozoospermic patients, by bisulphite genomic sequencing. We here report that 7 out of 15 (46.7%) patients with a sperm count below 10 3 10 6 /ml display defective methylation of H19 and/or MEST imprinted genes. In these cases, hypomethylation was observed in 5.54% (1.2– 8.3%) and complete unmethylation in 2.95% (0 –5.9%) of H19 clones. Similarly, for the CTCF-binding site 6, hypomethylation occurred in 4.8% (1.2 –8.9%) and complete unmethylation in 3.7% (0 – 6.9%) of the clones. Conversely, hypermethylation occurred in 8.3% (3.8– 12.2%) and complete methylation in 6.1% (3.8 – 7.6%) of MEST clones. Of the seven patients presenting imprinting errors, two had both H19 hypomethylation and MEST hypermethylation, whereas five displayed only one imprinted gene affected. The frequency of patients with MEST hypermethylation was highest in the severe oligozoospermia group (2/5 patients), whereas H19 hypomethylation was more frequent in the moderate oligozoospermia (2/5 patients). In all cases, global sperm genome methylation analysis (LINE1 transposon) suggested that defects were specific for imprinted genes. These findings could contribute to an explanation of the cause of Silver –Russell syndrome in children born with H19 hypomethylation after assisted reproductive technologies (ART). Additionally, unmethylation of the CTCF-binding site could lead to inactivation of the paternal IGF2 gene, and be linked to decreased embryo quality and birth weight, often associated with ART. more...
- Published
- 2008
20. Unique t(Y;1)(q12;q12) reciprocal translocation with loss of the heterochromatic region of chromosome 1 in a male with azoospermia due to meiotic arrest: a case report
- Author
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Joaquina Silva, Alberto Barros, Paula María de Carvalho Pinto Costa, Cláudia Alves, Maria João Pinho, Mário Sousa, Susana Fernandes, Carolina Almeida, Rui Neves, Luis Ferrás, and Cristina Ferrás
- Subjects
Adult ,Male ,medicine.medical_specialty ,Heterochromatin ,Chromosomal translocation ,Apoptosis ,Biology ,Y chromosome ,Translocation, Genetic ,Meiosis ,medicine ,Humans ,Cells, Cultured ,In Situ Hybridization, Fluorescence ,Chromosomes, Human, Y ,Rehabilitation ,Cytogenetics ,Obstetrics and Gynecology ,Chromosome ,Karyotype ,Oligospermia ,Molecular biology ,Spermatozoa ,Testis determining factor ,Reproductive Medicine ,Chromosomes, Human, Pair 1 ,Karyotyping ,Cytogenetic Analysis ,Gene Deletion - Abstract
A de novo reciprocal translocation 46,X,t(Y;1)(q12;q12) was found in an azoospermic male with meiotic arrest. Cytogenetics and fluorescent in situ hybridization (FISH) were used to define the karyotype, translocation breakpoints and homologue pairing. SRY (Yp), Yq11.2-AZF regions, DAZ gene copies and the distal Yq12 heterochromatin were studied by PCR and restriction analysis using sequence-tagged sites and single nucleotide variants. High resolution GTL, CBL and DA-DAPI staining revealed a (Y;1) translocation in all metaphases and a normal karyotype in the patient’s father. FISH showed the presence of the distal Yq12 heterochromatic region in der(1) and loss of the heterochromatic region of chromosome 1. PCR demonstrated the intactness of the Y chromosome, including the SRY locus, AZF regions, DAZ genes and distal heterochromatin. A significant decrease (P 5 0.005) of Xp/Yp pairing (18.6%), as compared with controls (65.7%), was found in arrested primary spermatocytes, and cell culture and mRNA expression studies confirmed an irreversible arrest at meiosis I, with induction of apoptosis and removal of germ cells by Sertoli cells. We characterized a de novo t(Y;1)(q12;q12) balanced reciprocal translocation with loss of the heterochromatic region of chromosome 1, that caused unpairing of sex chromosomes followed by meiosis I arrest, apoptotic degeneration of germ cells and azoospermia. more...
- Published
- 2005
21. Direct access to polycyclic peripheral diepoxy-meso-quinone derivatives from acene catalytic oxidation
- Author
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M. Graça P. M. S. Neves, Margarida Linhares, Cristina Freire, Paula María de Carvalho Pinto Costa, and Susana L.H. Rebelo
- Subjects
Hydrogen ,General Chemical Engineering ,chemistry.chemical_element ,General Chemistry ,Photochemistry ,Adduct ,Catalysis ,Quinone ,Pentacene ,chemistry.chemical_compound ,Tetracene ,chemistry ,Catalytic oxidation ,Acene - Abstract
The unprecedented epoxidation on the peripheral positions of tetracene and pentacene with hydrogen peroxide-urea adduct catalyzed by the metalloporphyrin [Mn(TDCPP)Cl] is reported under mild conditions, affording the direct polyfunctionalization of the acenes to anti-diepoxy-meso-quinone derivatives. more...
- Published
- 2013
- Full Text
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