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info:eu-repo/grantAgreement/EC/H2020/787410/EU The work was also partially funded by the Nanomark collaborative project between INCM (Imprensa Nacional - Casa da Moeda). Publisher Copyright: © 2021 The Author(s). Published by IOP Publishing Ltd. Titanium dioxide nanoparticles and nanostructured thin films were simultaneously synthesized using a microwave-assisted hydrothermal method. The synthesis formed very fine particles, appearing as nanospheres in the 11 nm size range. As for the nanostructured films, they have displayed similar structural characteristics to the nanoparticles, with thickness of 130 nm. These films covered uniformly and homogenously the Whatman paper, while maintaining its flexibility. The materials processed had their photocatalytic activity assessed from rhodamine B degradation under solar radiation (91% degradation after 40 min for the powder material and 68% after 6 h for the nanostructured thin films). Reusability experiments were also carried out, revealing superior performance concerning the Degussa P25, the most common photocatalyst used. The results of the present work can be thought as an option for the existing photocatalysts activated under solar light, namely for water purification, as it simultaneously produces enhanced photocatalytic powders and photocatalytic papers fully disposable and that can be easily recycled. publishersversion published

A linear decapeptide containing three His and one Asp residues and a β-turn-inducing dProPro unit was synthesised. A detailed potentiometric, mass spectrometric and spectroscopic study showed that at a 1:1 ratio of CCu /Cpeptide this peptide formed a major [CuH(O(dPro)-Asp)](2+) species (pH range 5.5-7.0), in which the Cu(2+) ion was bound to the His and Asp residues in square-planar or square-pyramidal geometries. The stability constant corrected for protonated species (log K* CuH(O dPro-Asp)=9.33) is almost equal to the value obtained for the parent [CuH(OAsp)](2+) species (log K*CuH(O-Asp) =9.28), but lower than that obtained for the cyclic [CuH(C-Asp)](2+) complex (log K*CuH(C-Asp) =10.79) previously published. Thus, the replacement of the ProGly unit by the stronger β-turn-inducing dProPro unit did not generate a more stable copper(II) species, although the O(dPro)-Asp peptide was structured in solution, as shown by circular dichroism (CD) spectroscopy. Interestingly, the calculated value of Keff showed that this peptide behaved similarly to the O-Asp or C-Asp counterparts, depending on the pH value. The cyclic voltammetry data indicated that the most easily reducible species were [CuH(O-Asp)](2+) (E'(0) =262 mV versus a normal hydrogen electrode (NHE)) and [CuH(O(dPro)-Asp)](2+) (E'(0) =294 mV versus NHE) complexes, the peptidic scaffolds of which are open. A lower value was obtained for [CuH(C-Asp)](2+) (E'(0) =24 mV versus NHE). A different degree of non-reversibility was observed for the three copper(II) complexes; this could reflect a different degree of flexibility in their respective peptidic scaffolds.

Tese de mestrado em Bioquímica, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2016 Submitted by Cristina Manessiez (camanessiez@fc.ul.pt) on 2017-03-24T16:08:50Z No. of bitstreams: 1 ulfc121226_tm_Ana_Fonseca.pdf: 4209028 bytes, checksum: 45cf87be733beaa6633e9042bec089f4 (MD5) Made available in DSpace on 2017-03-24T16:09:00Z (GMT). No. of bitstreams: 1 ulfc121226_tm_Ana_Fonseca.pdf: 4209028 bytes, checksum: 45cf87be733beaa6633e9042bec089f4 (MD5) Previous issue date: 2016

OBJECTIVES The purposes of this study were the development and preclinical evaluation of clinically translatable E-selectin-specific ultrasound contrast agents based on a peptide ligand with the recognition sequence IELLQAR. MATERIALS AND METHODS The E-selectin-specific peptide was synthesized through solid phase peptide synthesis and covalently attached to poly n-butylcyanoacrylate-stabilized microbubbles with an air core. Quantification of the microbubble surface coverage with peptides was performed through flow cytometry. Targeted adhesion of peptide-coated microbubbles was investigated in vitro using parallel plate flow chamber assays on tumor necrosis factor-α-stimulated human umbilical vein endothelial cells. In vivo imaging was performed in nude mice bearing human ovarian carcinoma xenografts (MLS), followed by ex vivo immunohistochemistry validation of E-selectin expression. RESULTS Success of peptide synthesis was validated through preparative reverse phase high-pressure liquid chromatography and electronspray ionization-mass spectrometry. Results of the flow cytometry revealed approximately 4000 E-selectin-specific peptides/microbubble surface. Results of the in vitro experiments demonstrated the specificity of peptide-coated microbubbles to E-selectin (1.10 ± 0.48 vs 0.19 ± 0.09 bound microbubbles per cell, before and after competition respectively; P < 0.01). The in vivo imaging enabled specific assessment of E-selectin expression in MLS carcinoma xenografts (5.21 ± 3.41 vs 1.37 ± 0.67 contrast intensity before and after competition, respectively; P < 0.05). CONCLUSIONS Clinically translatable microbubbles that were covalently coupled to the short E-selectin-specific peptide (IELLQAR) enabled specific imaging of the E-selectin expression in tumor vessels in vivo.

Designing small peptides that are capable of binding Cu(2+) ions mainly through the side-chain functionalities is a hard task because the amide nitrogen atoms strongly compete for Cu(2+) ion coordination. However, the design of such peptides is important for obtaining biomimetic small systems of metalloenyzmes as well as for the development of artificial systems. With this in mind, a cyclic decapeptide, C-Asp, which contained three His residues and one Asp residue, and its linear derivative, O-Asp, were synthesized. The C-Asp peptide has two Pro-Gly β-turn-inducer units and, as a result of cyclization, and as shown by CD spectroscopy, its backbone is constrained into a more defined conformation than O-Asp, which is linear and contains a single Pro-Gly unit. A detailed potentiometric, mass spectrometric, and spectroscopic study (UV/Vis, CD, and EPR spectroscopy) showed that at a 1:1 Cu(2+)/peptide ratio, both peptides formed a major [CuHL](2+) species in the pH range 5.0-7.5 (C-Asp) and 5.5-7.0 (O-Asp). The corrected stability constants of the protonated species (log K*(CuH(O-Asp))=9.28 and log K*(CuH(C-Asp))=10.79) indicate that the cyclic peptide binds Cu(2+) ions with higher affinity. In addition, the calculated value of K(eff) shows that this higher affinity for Cu(2+) ions prevails at all pH values, not only for a 1:1 ratio but even for a 2:1 ratio. The spectroscopic data of both [CuHL](2+) species are consistent with the exclusive coordination of Cu(2+) ions by the side-chain functionalities of the three His residues and the Asp residue in a square-planar or square-pyramidal geometry. Nonetheless, although these data show that, upon metal coordination, both peptides adopt a similar fold, the larger conformational constraints that are present in the cyclic scaffold results in different behaviour for both [CuHL](2+) species. CD and NMR analysis revealed the formation of a more rigid structure and a slower Cu(2+)-exchange rate for [CuH(C-Asp)](2+) compared to [CuH(O-Asp](2+). This detailed comparative study shows that cyclization has a remarkable effect on the Cu(2+)-coordination properties of the C-Asp peptide, which binds Cu(2+) ions with higher affinity at all pH values, stabilizes the [CuHL](2+) species in a wider pH range, and has a slower Cu(2+)-exchange rate compared to O-Asp.

The acetohydroxamic acid synthesis reaction was studied using whole cells, cell-free extract and purified amidase from the strains of Pseudomonas aeruginosa L10 and AI3 entrapped in a reverse micelles system composed of cationic surfactant tetradecyltrimethyl ammonium bromide. The specific activity of amidase, yield of synthesis and storage stability were determined for the reversed micellar system as well as for free amidase in conventional buffer medium. The results have revealed that amidase solutions in the reverse micelles system exhibited a substantial increase in specific activity, yield of synthesis and storage stability. In fact, whole cells from P. aeruginosa L10 and AI3 in reverse micellar medium revealed an increase in specific activity of 9.3- and 13.9-fold, respectively, relatively to the buffer medium. Yields of approximately 92% and 66% of acetohydroxamic acid synthesis were obtained for encapsulated cell free extract from P. aeruginosa L10 and AI3, respectively. On the other hand, the half-life values obtained for the amidase solutions encapsulated in reverse micelles were overall higher than that obtained for the free amidase solution in buffer medium. Half-life values obtained for encapsulated purified amidase from P. aeruginosa strain L10 and encapsulated cell-free extract from P. aeruginosa strain AI3 were of 17.0 and 26.0 days, respectively. As far as the different sources biocatalyst are concerned, the data presented in this work has revealed that the best results, in both storage stability and biocatalytic efficiency, were obtained when encapsulated cell-free extract from P. aeruginosa strain AI3 at w0 of 10 were used. Conformational changes occurring upon encapsulation of both strains enzymes in reverse micelles of TTAB in heptane/octanol were additionally identified by FTIR spectroscopy which clarified the biocatalysts performances.

Num mundo actual dominado por uma feroz competição, a definição de uma estratégia empresarial clara e coerente é um factor decisivo para o sucesso de qualquer organização. O presente trabalho tem como objectivo, partindo da análise de um caso de estudo concreto, fazer a apresentação das principais ferramentas disponíveis para a definição dessa mesma estratégia e para a sua certificação. O trabalho está dividido em duas partes distintas: Caso de Estudo e Nota Pedagógica. Em relação ao Caso de Estudo, que ocupa um segmento de consultoria no vasto mercado da publicidade, são apresentadas e analisadas as condições gerais desse mercado, bem como a Film Brokers e toda a respectiva envolvente, com especial incidência nos clientes e nos concorrentes. Todos os elementos contidos nesta primeira parte foram recolhidos junto de empresas especializadas no mercado e na comunicação social (entrevistas). No tocante à nota pedagógica, é feita uma introdução aos seus objectivos, bem como uma revisão da literatura referente às ferramentas de definição estratégica. Segue-se-lhes a resolução, na qual é feita a aplicação dos modelos considerados mais adequados às especificidades do mercado e às condições da empresa. Estes elementos foram recolhidos junto de referências bibliográficas já existentes. Os resultados da aplicação dos modelos apontam para ajustes nos caminhos escolhidos, de forma a potenciar os factores críticos de sucesso da empresa. Contudo, e de uma forma geral, confirmam as opções já tomadas. In a World ruled by hard fierce competition, defining a clear and consistent business strategy is an essential step to any company’s success. This study analyses a particular case a way to present the main available tools for the definition of this strategy and for its certification. This study is divided in two parts: the Case Study and the Pedagogical Note. The Case Study refers to the consultancy firm Film Brokers working in the vast communication and advertisement Market: an examination of the general conditions of the market is made, as well as an analysis of the firm and its business environment, namely customers and competitors. All this information was collected from companies working in the same market area and from media sources (interviews). The Pedagogical Note includes and introduction about its aims, followed by a review of the literature focused on business strategy definition tools. The resolution that follows consists of the application of some of those tools to the analysis of the case study. The models applied show the need of small adjustments in the strategic paths choses by Film Brokers in order to maximize the main competitive advantages. However, in a general way, they confirm the strategies already adopted.

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics

Two decapeptides containing three His and two Pro-Gly β-turn inducer units (C-Asn, cyclic) and three His and a single Pro-Gly unit (O-Asn, open) have been synthesized. A detailed potentiometric study showed that while O-Asn binds up to 3 equiv. of Cu(2+) ions, C-Asn only coordinates two before precipitation occurred. Nonetheless, at a 1 : 1 Cu(2+)/peptide ratio both peptides form a major [CuHL](3+) species and spectroscopic studies (UV-Vis, CD and EPR) revealed a very similar copper(ii) complex where the metal ion is coordinated solely by the imidazole rings of the His residues adopting a square planar or square pyramidal geometry. The corrected stability constants of the protonated species (log K(CuH(O-Asn)) = 8.17 and log K(CuH(C-Asn)) = 9.11) indicate that the cyclic peptide binds Cu(2+) with higher affinity and this value represents the highest value reported so far for this type of coordination. Additionally, the calculated value of the effective stability constant, K(eff), showed that C-Asn has a higher affinity for Cu(2+) at all pH values not only at a 1 : 1 ratio but even at a 2 : 1 ratio. The replacement of the asparagine residue by an aspartic amino acid increases the Cu(2+) affinity of the aspartic counterparts, C-Asp and O-Asp, which at a 1 : 1 Cu(2+)/peptide ratio also form a major species, [CuHL](2+) in these cases, with Cu(2+) coordinated to the three histidine residues and one aspartic residue. These data show how cyclization and coordination to the aspartic residue increase the binding strength and preclude the coordination of the amide nitrogen up to higher pH values, stabilizing therefore, the species where Cu(2+) is solely coordinated by the side chain functionalities.