Spectroscopic characterization of novel push-pull thieno[3,2-b]thiophene derivatives functionalized with different acceptor groups.

Push-pull π-conjugated systems of the thiophene type have several interesting applications as nonlinear optical (NLO) and photochromic materials, sensitizers for dye sensitized solar cells (DSSCs), etc. As part of an on-going research to develop efficient donor-acceptor substituted heterocyclic systems for diverse applications such as NLO and organic sensitizers for DSSCs, we report in this communication the synthesis and characterization of two novel heterocyclic compounds 1-2, using several synthetic methodologies. These new push-pull systems are based on a furan donor moiety and a thieno[3,2-b]thiophene spacer, functionalized with different electron withdrawing groups. The full characterization of the new compounds was performed using UV-visible (absorption and emission), 1H NMR and IR spectroscopies. The experimental results showed that the optical and electronic properties of these push-pull systems can be readily tuned by varying the electron-acceptor strength of the groups linked to the thieno[3,2-b]thiophene π-bridge. Moreover, their push-pull character with a significant intramolecular charge transfer (ICT) from the donor furan heterocycle to the acceptor groups and a high polarizability of the whole π-conjugated systems reveal their potential application as chromophores for NLO and/or as sensitizers for DSSCs.FCTFEDERQRE

Benzothiadiazole derivatives functionalized with two different (hetero)aromatic donor groups: synthesis and evaluation as TiO2 sensitizers for DSSCs

A series of benzothiadiazole-based push-pull heterocyclic systems were synthesized and characterized in order to study the variations induced by different aromatic and heterocyclic donor groups in the optical, electronic and photovoltaic properties of DSSCs prepared with the respective cyanoacetic acid derivatives. The organic sensitizers bear a 5-hexyl-2,2’-bithienyl or N,N-diphenylanilino donor moieties conjugated with a thienyl-benzothiadiazole spacer functionalized with the electron acceptor/anchoring cyanoacetic acid group. The solar cell based on TiO2 sensitized with the novel dye bearing the 5-hexyl-2,2’-bithienyl donor, exhibited a power conversion efficiency of 0.95 % due the inefficient electron injection. Co-adsorption studies of the same dye resulted in enhanced photovoltaic conversion efficiency of 2.49 %, which represents an improvement of cell efficiency of 260 %. The sensitizer bearing the N,N-diphenylanilino donor exhibited 4.51 % power conversion efficiency, that was further enhanced by co-sensitization to 5.22 % efficiency.Thanks are due to Fundação para a Ciência e Tecnologia (FCT) for a PhD grant to S. S. M. Fernandes (SFRH/BD/87786/2012) and FEDERCOMPETE for financial support through the CQ/UM (Ref. UID/QUI/ 00686/2013 and UID/QUI/0686/2016). The NMR spectrometer Bruker Avance III 400 is part of the National NMR Network and was purchased within the framework of the National Program for Scientific Re-equipment, contract REDE/1517/RMN/2005 with funds from POCI 2010 (FEDER) and FCT. A. Pereira, D. Ivanou, and A. Mendes would like to acknowledge the European Commission through the Seventh Framework Programme, the Scientific Programme “Ideas” of the European Research Council for research and technological development as part of an Advanced Grant under grant agreement No 321315, which also partially funded this work.info:eu-repo/semantics/publishedVersio

Terpyridine derivatives functionalized with (hetero)aromatic groups and the corresponding Ru complexes: synthesis and characterization as SHG chromophores

Push–pull terpyridine derivatives were synthesized and characterized in order to study the variations produced in their optical and electronic properties by linking different (hetero)aromatic electron donor moieties at position 4 of the electron deficient terpyridine moiety. The final donor-acceptor systems were synthesized in fair to good yields by Kröhnke condensation of the precursor aldehydes, with 2-acetylpyridine. Hyper-Rayleigh scattering in dioxane solutions using a fundamental wavelength of 1064 nm was employed to evaluate their second-order nonlinear optical properties. Terpyridine derivative functionalized with the 9-ethyl-9H-carbazolyl group exhibited the largest first hyperpolarizability (beta = 610 × 10-30 esu, using the T convention) thus indicating its potential application as a second harmonic generation (SHG) chromophore. Terpyridine derivatives were also used as ligands for the synthesis of novel [RuII(tpy)(NCS)3]– complexes, prepared in good yields by a two-step procedure involving the preparation of [RuIII(tpy)(Cl3] as precursors. RutheniumII complexes display a broad absorption in the visible range, accounting for their very dark color. Their redox behaviour is mainly characterized by the RuII-RuIII oxidation and by the ligand-centred reduction, whose potentials can be finely tuned by the electronic properties of the aromatic substituents on the terpyridine ligand. Hyper-Rayleigh scattering in methanol solutions using a fundamental wavelength of 1064 nm was also employed to evaluate their second-order nonlinear optical properties.Thanks are due to Fundação para a Ciência e a Tecnologia and FEDERCOMPETE for financial support through Centro de Química (UID/QUI/ 00686/2013 and UID/QUI/0686/2016), and a PhD grant to S. S. M. Fernandes (SFRH/BD/87786/2012). The NMR spectrometer Bruker Avance III 400 is part of the National NMR Network and was purchased with funds from FCT and FEDER. The pulsed laser system was acquired within the framework of the grant (PTDC/CTM/105597/2008) from the Portuguese Foundation for Science and Technology (FCT) with funding from FEDER-COMPETE.info:eu-repo/semantics/publishedVersio

Avaliação de métodos de caracterização de betumes modificados

Os betumes modificados são usados na pavimentação para minimizar os principais problemas das misturas betuminosas. Contudo estes possuem características diferentes dos betumes convencionais, sendo a caracterização básica utilizada nos betumes convencionais insuficiente para a sua correta/completa caracterização. Assim, o principal objetivo deste estudo é a avaliação de diferentes betumes modificados (com óleo de motor usado e um polímero) e a sua comparação com um betume modificado comercial, através de ensaios de caracterização básica e avançada. Concluiu-se que dois dos betumes modificados com óleo de motor usado e SBS apresentam características iguais e/ou superiores ao betume modificado comercial. Para além disso, os resultados dos ensaios são muito condicionados pelas condições a que são realizados e que a caracterização avançada é essencial para complementar os ensaios de caracterização básica.FEDER através do Programa Operacional de Competitividade – COMPETE e por fundos nacionais através da FCT – Fundação para a Ciência e Tecnologia no âmbito da bolsa de doutoramento (SFRH/BD98379/2013

ESTRATÉGIAS PARA A HUMANIZAÇÃO DOS CUIDADOS À CRIANÇA - INTERVENÇÃO DO ENFERMEIRO ESPECIALISTA EM SAÚDE INFANTIL E PEDIÁTRICA

Introdução: A hospitalização confere vulnerabilidade à criança e família, desencadeando sentimentos como medo e insegurança. Ambos são colocados num ambiente desconhecido com novas rotinas. Perante esta problemática, o Enfermeiro Especialista em Saúde Infantil e Pediátrica deve procurar intervir humanizando os seus cuidados, minimizando o impacto da hospitalização. Objetivos: Identificar produção científica relativa às estratégias de humanização em Enfermagem em contexto pediátrico. Metodologia: Revisão Integrativa da Literatura efetuada nas bases de dados: CINAHL Complete; MEDLINE Complete; Nursing & Allied Health Collection: Comprehensive; Cochrane Central Register of Controlled Trials e MedicLatina, disponíveis no motor de busca EBSCO, publicados entre 2012 e 2022. A seleção e análise de relevância dos artigos foi efetuada pelos revisores de forma independente. Resultados: Dos 240 artigos iniciais foram selecionados 16 artigos, segundo critérios previamente definidos. A maioria dos estudos referem a ludoterapia como uma das intervenções que deve ser utilizada pelo EESIP na humanização dos cuidados. O cuidado centrado na família, e a humanização das estrutura e ambientes organizacionais, são outras das intervenções mencionadas. Conclusão: Esta pesquisa evidencia as intervenções que contribuem para a humanização dos cuidados de forma a melhorar a qualidade dos cuidados e potenciar um crescimento e desenvolvimento saudáveis das crianças. Será importante, para isso, promover a formação dos profissionais, assumir a ludoterapia como fator preponderante, adequar estruturas e ambientes a cada etapa de desenvolvimento, sendo estes cuidados centrados nas famílias

Push-pull heterocyclic dyes based on pyrrole and thiophene: synthesis and evaluation of their optical, redox and photovoltaic properties

Three heterocyclic dyes were synthesized having in mind the changes in the photovoltaic, optical and redox properties by functionalization of 5-aryl-thieno[3,2-b]thiophene, 5-arylthiophene and bis-methylpyrrolylthiophene π-bridges with different donor, acceptor/anchoring groups. Knoevenagel condensation of the aldehyde precursors with 2-cyanoacetic acid was used to prepare the donor-acceptor functionalized heterocyclic molecules. These organic metal-free dyes are constituted by thieno[3,2-b]thiophene, arylthiophene, bis-methylpyrrolylthiophene, spacers and one or two cyanoacetic acid acceptor groups and different electron donor groups (alkoxyl, and pyrrole electron-rich heterocycle). The evaluation of the redox, optical and photovoltaic properties of these compounds indicate that 5-aryl-thieno[3,2-b]thiophene-based dye functionalized with an ethoxyl electron donor and a cyanoacetic acid electron acceptor group/anchoring moiety displays as sensitizer for DSSCs the best conversion efficiency (2.21%). It is mainly assigned to the higher molar extinction coefficient, long π-conjugation of the heterocyclic system, higher oxidation potential and strong electron donating capacity of the ethoxyl group compared to the pirrolyl moiety.Thanks are due to the Fundacao para a Ciencia e Tecnologia (FCT) for a PhD grant to S.S.M. Fernandes (SFRH/BD/87786/2012) and to FEDER-COMPETE for financial support at the research center CQUM (UID/QUI/0686/2016) and (UID/QUI/0686/2020). The NMR spectrometers are part of the National NMR Network (PTNMR) and are partially supported by Infrastructure Project No. 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC). The group in Porto would like to acknowledge the European Commission through the Seventh Framework Programme, the Specific Programme "Ideas" of the European Research Council for research and technological development as part of an Advanced Grant under Grant No. 321315, which also partially funded this work. Some of this work was also performed under the project "SunStorage-Harvesting and storage of solar energy", with reference POCI-01-0145-FEDER-016387, funded by the European Regional Development Fund (ERDF), through COMPETE 2020-Operational Programme for Competitiveness and Internationalization (OPCI), and by national funds, through FCT. The group in Porto is also thankful to POCI-01-0145-FEDER-006939 (Laboratory for Process Engineering, Environment, Biotechnology and Energy-UID/EQU/00511/2013) funded by the European Regional Development Fund (ERDF), through COMPETE2020-Programa Operacional Competitividade e Internacionalizacao (POCI) and by national funds, LEPABE-2-ECO-INNOVATION, supported by the North Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERD). Institutional Review Board Statement: Not applicable

ESTRATÉGIAS PARA A HUMANIZAÇÃO DOS CUIDADOS À CRIANÇA - INTERVENÇÃO DO ENFERMEIRO ESPECIALISTA EM SAÚDE INFANTIL E PEDIÁTRICA

Introduction: Hospitalization confers vulnerability to the child and family, triggering feelings such as fear and insecurity. Both are placed in an unfamiliar environment, with new routines. Faced with this problem, the Specialist Nurse in Child and Pediatric Health should seek to intervene by humanizing their care and minimizing the impact of hospitalization. Objectives: To identify scientific production related to humanization practices in Nursing in a pediatric context. Methodology: Integrative Literature Review carried out in the databases: CINAHL Complete; MEDLINE Complete; Nursing & Allied Health Collection: Comprehensive; Cochrane Central Register of Controlled Trials and MedicLatina, available on the EBSCO search engine, published between 2012 and 2022. The selection and relevance analysis of the articles was performed by the reviewers independently. Results: Of the 240 initial articles, 16 articles were selected, according to previously defined criteria. Most studies refer to ludotherapy as one of the interventions that should be used by the EESIP in the humanization of care. Family-centered care and the humanization of organizational structures and environments are other interventions mentioned. Conclusion: This research shows the interventions that motivated the humanization of care in order to improve the quality of care and enhance the healthy growth and development of children. It will be important, for this, to promote the training of professionals, assuming play therapy as a preponderant factor, structures and environments suitable for each stage of development, with this care centered on families.Introdução: A hospitalização confere vulnerabilidade à criança e família, desencadeando sentimentos como medo e insegurança. Ambos são colocados num ambiente desconhecido com novas rotinas. Perante esta problemática, o Enfermeiro Especialista em Saúde Infantil e Pediátrica deve procurar intervir humanizando os seus cuidados, minimizando o impacto da hospitalização. Objetivos: Identificar produção científica relativa às estratégias de humanização em Enfermagem em contexto pediátrico. Metodologia: Revisão Integrativa da Literatura efetuada nas bases de dados: CINAHL Complete; MEDLINE Complete; Nursing & Allied Health Collection: Comprehensive; Cochrane Central Register of Controlled Trials e MedicLatina, disponíveis no motor de busca EBSCO, publicados entre 2012 e 2022. A seleção e análise de relevância dos artigos foi efetuada pelos revisores de forma independente. Resultados: Dos 240 artigos iniciais foram selecionados 16 artigos, segundo critérios previamente definidos. A maioria dos estudos referem a ludoterapia como uma das intervenções que deve ser utilizada pelo EESIP na humanização dos cuidados. O cuidado centrado na família, e a humanização das estrutura e ambientes organizacionais, são outras das intervenções mencionadas. Conclusão: Esta pesquisa evidencia as intervenções que contribuem para a humanização dos cuidados de forma a melhorar a qualidade dos cuidados e potenciar um crescimento e desenvolvimento saudáveis das crianças. Será importante, para isso, promover a formação dos profissionais, assumir a ludoterapia como fator preponderante, adequar estruturas e ambientes a cada etapa de desenvolvimento, sendo estes cuidados centrados nas famílias

Synthesis and characterization of novel thieno[3,2-b]thiophene based metal-free organic dyes with different heteroaromatic donor moieties as sensitizers for dye-sensitized solar cells

Four novel heterocycle dyes 3a-d were synthesized in order to study the variations produced in the optical, electronic and photovoltaic properties by substitution of different electron-rich heterocyclic groups to the thieno[3,2-b]thiophene system. The final push-pull conjugated dyes 3a-d were synthesized by Suzuki-Miyaura coupling reaction followed by Knoevenagel condensation of the corresponding aldehyde precursors with cyanoacrylic acid 2a-d. These new push-pull systems are based on a thieno[3,2-b]thiophene spacer, a cyanoacetic acid anchoring group and several electron-rich heterocycles (thiophene, pyrrole and furan) as donor groups. The multidisciplinary study concerning the optical, redox and photovoltaic characterization of the dyes reveals that compound 3b bearing a hexyl-bithiophene donor group/heterocyclic spacer exhibits the best overall conversion efficiency (2.49%) as sensitizer in nanocrystalline TiO2 dye sensitized solar cells. Co-adsorption studies between N719 and 3b revealed that upon addition of N719 co-adsorbent, the optimized cell efficiencies were improved by 16–77%. The best efficiency was 4.40%, corresponding to 54% of the photovoltaic performance of the N719-based DSSC fabricated and measured under similar conditions.FCTFEDERQRENEuropean Research Council (Contract no: 321315

Theoretical and experimental studies of aryl-bithiophene based push-pull pi-conjugated heterocyclic systems bearing cyanoacetic or rhodanine-3-acetic acid acceptors for SHG nonlinear optical applications

A series of push-pull aryl-bithiophene based systems 2-3 were designed and synthesized in order to understand how structural modifications influence the electronic, linear and nonlinear optical properties. The push-pull conjugated chromophores 2-3 bear a bithiophene spacer conjugated with a phenyl ring functionalized with N,N-dialkylamino electron-donor groups together with cyanoacetic or rhodanine-3-acetic acid acceptor groups. Theoretical (DFT calculations) and experimental studies were carried out to obtain information on conformation, electronic structure, electron distribution, dipolar moment, and molecular nonlinearity response of the push-pull bithiophene derivatives. This multidisciplinary study revealed that chromophore 2e exhibits the highest value for hyperpolarizability beta (10440 × 10-30 esu) due to the strong electron donating ability of the N,N-diethylamino group, and the ethyne linker that not only lengthens the pi- conjugation path but also grants less distortion to the system.Thanks are due to Fundação para a Ciência e Tecnologia (FCT) for a PhD grant to S. S. M. Fernandes (SFRH/BD/87786/2012) and FEDERCOMPETE for financial support through the CQ/UM (Ref. UID/QUI/ 00686/2013 and UID/QUI/0686/2016). The NMR spectrometer Bruker Avance III 400 is part of the National NMR Network and was purchased within the framework of the National Program for Scientific Reequipment, contract REDE/1517/RMN/2005 with funds from POCI 2010 (FEDER) and FCT. The pulsed laser system was acquired within the framework of the grant (PTDC/CTM/105597/2008) from the Fundação para a Ciência e Tecnologia (FCT) with funding from FEDERCOMPETE. This work was also supported by the Associated Laboratory for Sustainable Chemistry - Clean Processes and Technologies - LAQV which is financed by Portuguese national funds from FCT/MEC (UID/ QUI/50006/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER–007265).info:eu-repo/semantics/publishedVersio

Insights on Ultrafiltration-Based Separation for the Purification and Quantification of Methotrexate in Nanocarriers

The evaluation of encapsulation efficiency is a regulatory requirement for the characterization of drug delivery systems. However, the difficulties in efficiently separating nanomedicines from the free drug may compromise the achievement of accurate determinations. Herein, ultrafiltration was exploited as a separative strategy towards the evaluation of methotrexate (MTX) encapsulation efficiency in nanostructured lipid carriers and polymeric nanoparticles. The effect of experimental conditions such as pH and the amount of surfactant present in the ultrafiltration media was addressed aiming at the selection of suitable conditions for the effective purification of nanocarriers. MTX-loaded nanoparticles were then submitted to ultrafiltration and the portions remaining in the upper compartment of the filtering device and in the ultrafiltrate were collected and analyzed by HPLC-UV using a reversed-phase (C18) monolithic column. A short centrifugation time (5 min) was suitable for establishing the amount of encapsulated MTX in nanostructured lipid carriers, based on the assumption that the free MTX concentration was the same in the upper compartment and in the ultrafiltrate. The defined conditions allowed the efficient separation of nanocarriers from the free drug, with recoveries of >85% even when nanoparticles were present in cell culture media and in pig skin surrogate from permeation assays.info:eu-repo/semantics/publishedVersio