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Submitted
Luna, F, Bradbury JS, Lourenço JM.  Submitted.  OSCAR: A Noise Injection Framework for Concurrent Java Programs.
2024
Choroba, K, Zowiślok B, Kula S, Machura B, Maroń {AM }, Erfurt K, Marques C, Cordeiro S, Baptista {PV}, Fernandes {AR}.  2024.  Optimization of Antiproliferative Properties of Triimine Copper(II) Complexes, nov. Journal Of Medicinal Chemistry. : ACS - American Chemical Society Abstract

Cu(II) complexes with 2,2':6',2″-terpyridines (terpy) and 2,6-bis(thiazol-2-yl)pyridines (dtpy) with 1- or 2-naphtyl and methoxy-naphtyl were synthesized to elucidate the impact of the triimine core, naphtyl linking mode, and presence of methoxy groups on the antiproliferative activity of [CuCl 2(L n )]. Their antiproliferative effect was analyzed in ovarian (A2780) and colorectal (HCT116) carcinomas and colorectal carcinoma resistant to doxorubicin (HCT116-DoxR) cell lines and in normal human fibroblasts. Among all complexes, the 1- and 2-naphtyl substituted terpy Cu(II) complexes ( Cu1a and Cu1b) showed the strongest cytotoxicity, namely, in HCT116-DoxR 2Dcells and were also capable of inducing the loss of cell viability in 3D HCT116-DoxR spheroids. Their intracellular localization, capability to increase reactive oxygen species (ROS), and interaction with DNA (nonintercalative mode) trigger oxidative DNA cleavage leading to cell death by apoptosis and autophagy. Cu1a and Cu1b do not show in vivo toxicity in a chicken embryo and can interact with bovine serum albumin (BSA).

Choroba, K, Zowislok B, Kula S, Machura B, Maron AM, Erfurt K, Cordeiro S, Baptista PV, Fernandes {AR}.  2024.  Optimization of Antiproliferative Properties of Triimine Copper(II) Complexes, nov. Journal Of Medicinal Chemistry. 67:19475–19502., Number 21: ACS - American Chemical Society Abstract

Cu(II) complexes with 2,2′:6′,2″-terpyridines (terpy) and 2,6-bis(thiazol-2-yl)pyridines (dtpy) with 1- or 2-naphtyl and methoxy-naphtyl were synthesized to elucidate the impact of the triimine core, naphtyl linking mode, and presence of methoxy groups on the antiproliferative activity of [CuCl2(Ln)]. Their antiproliferative effect was analyzed in ovarian (A2780) and colorectal (HCT116) carcinomas and colorectal carcinoma resistant to doxorubicin (HCT116-DoxR) cell lines and in normal human fibroblasts. Among all complexes, the 1- and 2-naphtyl substituted terpy Cu(II) complexes (Cu1a and Cu1b) showed the strongest cytotoxicity, namely, in HCT116-DoxR 2Dcells and were also capable of inducing the loss of cell viability in 3D HCT116-DoxR spheroids. Their intracellular localization, capability to increase reactive oxygen species (ROS), and interaction with DNA (nonintercalative mode) trigger oxidative DNA cleavage leading to cell death by apoptosis and autophagy. Cu1a and Cu1b do not show in vivo toxicity in a chicken embryo and can interact with bovine serum albumin (BSA).

Choroba, K, Zowiślok B, Kula S, Machura B, Maroń {AM }, Erfurt K, Marques C, Cordeiro S, Baptista {PV}, Fernandes {AR}.  2024.  Optimization of Antiproliferative Properties of Triimine Copper(II) Complexes. Journal Of Medicinal Chemistry. 67:19475–19502., Number 21: ACS - American Chemical Society Abstract

Cu(II) complexes with 2,2′:6′,2″-terpyridines (terpy) and 2,6-bis(thiazol-2-yl)pyridines (dtpy) with 1- or 2-naphtyl and methoxy-naphtyl were synthesized to elucidate the impact of the triimine core, naphtyl linking mode, and presence of methoxy groups on the antiproliferative activity of [CuCl2(Ln)]. Their antiproliferative effect was analyzed in ovarian (A2780) and colorectal (HCT116) carcinomas and colorectal carcinoma resistant to doxorubicin (HCT116-DoxR) cell lines and in normal human fibroblasts. Among all complexes, the 1- and 2-naphtyl substituted terpy Cu(II) complexes (Cu1a and Cu1b) showed the strongest cytotoxicity, namely, in HCT116-DoxR 2Dcells and were also capable of inducing the loss of cell viability in 3D HCT116-DoxR spheroids. Their intracellular localization, capability to increase reactive oxygen species (ROS), and interaction with DNA (nonintercalative mode) trigger oxidative DNA cleavage leading to cell death by apoptosis and autophagy. Cu1a and Cu1b do not show in vivo toxicity in a chicken embryo and can interact with bovine serum albumin (BSA).

2023
Neto, {JP }, Mota A, c}alo Lopes G{\c, Coelho {BJ }, Frazão J, Moura {AT }, Oliveira B, Sieira B, Fernandes J, Fortunato E, Martins R, Igreja R, Baptista {PV}, Águas H.  2023.  Open-source tool for real-time and automated analysis of droplet-based microfluidic, jul. Lab On A Chip. 23:3238–3244., Number 14: RSC - Royal Society of Chemistry Abstract

Droplet-based microfluidic technology is a powerful tool for generating large numbers of monodispersed nanoliter-sized droplets for ultra-high throughput screening of molecules or single cells. Yet further progress in the development of methods for the real-time detection and measurement of passing droplets is needed for achieving fully automated systems and ultimately scalability. Existing droplet monitoring technologies are either difficult to implement by non-experts or require complex experimentation setups. Moreover, commercially available monitoring equipment is expensive and therefore limited to a few laboratories worldwide. In this work, we validated for the first time an easy-to-use, open-source Bonsai visual programming language to accurately measure in real-time droplets generated in a microfluidic device. With this method, droplets are found and characterized from bright-field images with high processing speed. We used off-the-shelf components to achieve an optical system that allows sensitive image-based, label-free, and cost-effective monitoring. As a test of its use we present the results, in terms of droplet radius, circulation speed and production frequency, of our method and compared its performance with that of the widely-used ImageJ software. Moreover, we show that similar results are obtained regardless of the degree of expertise. Finally, our goal is to provide a robust, simple to integrate, and user-friendly tool for monitoring droplets, capable of helping researchers to get started in the laboratory immediately, even without programming experience, enabling analysis and reporting of droplet data in real-time and closed-loop experiments.

2022
Luna, F, Bradbury JS, Lourenço JM.  2022.  OSCAR - A Java Noise Injection Framework, 8-9 Sep.. Atas do INForum 2022. , Instituto Politécnico da Guardalbl22_-_oscar.pdf
Panigrahi, S, Calmeiro T, Mendes MJ, Águas H, Fortunato E, Martins R.  2022.  Observation of Grain Boundary Passivation and Charge Distribution in Perovskite Films Improved with Anti-solvent Treatment. Journal of Physical Chemistry C. 126(45):19367–19375.
2021
Branco, S, Mateus EP, Richter Gomes da Silva MD, Mendes D, Araujo Pereira MM, Schuetz S, Paiva MR.  2021.  Olfactory responses of Anaphes nitens (Hymenoptera, Mymaridae) to host and habitat cues, AUG. JOURNAL OF APPLIED ENTOMOLOGY. 145:675-687., Number 7 Abstract

The eucalyptus weevil, Gonipterus spp. Schoenherr, 1833 (Coleoptera, Curculionidae) is considered a major pest of eucalyptus plantations. In regions where control is achieved, success is usually brought by the action of the solitary egg parasitoid Anaphes nitens (Girault, 1928) (Hymenoptera, Mymaridae). Research was conducted to ascertain which cues might mediate female wasp host location and selection. In Petri dish arenas, females were attracted to Gonipterus platensis Marelli, 1927 egg capsules, to G. platensis mated female faeces and to leaves of Eucalyptus globulus Labillardiere, 1799. Gas chromatography-mass spectrometry electroantennographic detection analysis was conducted using extracts obtained from leaves of E. globulus, from G. platensis egg capsules, as well as from adults of both sexes and their faeces, in order to detect and identify compounds perceived by the wasp's olfactory system. The parasitoids were shown to detect a wide range of compounds emitted by each one of these sources, and for 31 compounds, antennal response was confirmed by dose-response tests. Further behavioural trials were conducted in Petri dishes in order to decode the effect, on parasitoid behaviour, of selected compounds emitted by E. globulus and of the pheromones, emitted by the weevils on parasitoid behaviour. Attraction was observed to two compounds emitted by E. globulus, namely 1,8-cineole and gamma-terpinene, and to the main component of the male sex/aggregation pheromone, cis-verbenol. To our knowledge, this is the first report of attraction of a parasitoid from the family Mymaridae to a component of its host's sexual/aggregation pheromone. Similarly, to other egg parasitoid species, A. nitens females are likely to use the host plant volatiles as long-range host location cues and to adopt the `infochemical detour' strategy in order to get in the vicinity of their hosts.

Frazão, J, Palma SICJ, Costa HMA, Alves C, Roque ACA, Silveira M.  2021.  Optical Gas Sensing with Liquid Crystal Droplets and Convolutional Neural Networks. Sensors. 21(8):2854.PDF
Castro, D, Jaeger P, Baptista AC, Oliveira JP.  2021.  An Overview of High-Entropy Alloys as Biomaterials. Metals. 11(4):648. AbstractWebsite

High-entropy alloys (HEAs) have been around since 2004. The breakthroughs in this field led to several potential applications of these alloys as refractory, structural, functional, and biomedical materials. In this work, a short overview on the concept of high-entropy alloys is provided, as well as the theoretical design approach. The special focus of this review concerns one novel class of these alloys: biomedical high-entropy alloys. Here, a literature review on the potential high-entropy alloys for biomedical applications is presented. The characteristics that are required for these alloys to be used in biomedical-oriented applications, namely their mechanical and biocompatibility properties, are discussed and compared to commercially available Ti6Al4V. Different processing routes are also discussed.

Castro, D, Jaeger P, Baptista AC, Oliveira JP.  2021.  An Overview of High-Entropy Alloys as Biomaterials. Metals. 11:648.
2020
Pawlowski, S, Huertas RM, Galinha CF, Crespo JG, Velizarov S.  2020.  On operation of reverse electrodialysis (RED) and membrane capacitive deionisation (MCDI) with natural saline streams: A critical review. Desalination. 476:114183. AbstractWebsite

Environment-friendly production of power and clean water is one of the major goals of 2030 Agenda for Sustainable Development, and can be achieved by emerging electromembrane processes, such as reverse electrodialysis (RED) and membrane capacitive deionisation (MCDI). RED generates electricity from salinity gradient energy sources, while MCDI desalinates (mainly) brackish water. However, fouling, scaling, stack channels clogging and undesired uphill ionic transport can reduce the power output and salt removal efficiency in RED and MCDI, respectively. A practical overview of current problems and challenges of operating and monitoring these processes under real conditions is provided. Appropriate mitigation approaches, which might include feed water pre-treatment, in-situ cleaning strategies and/or development of new antifouling ion-exchange membranes (IEMs) are disclosed. First, a description, analysis and (when possible) normalised comparison of the performance of available RED and MCDI stacks, employing natural saline streams, is presented. Afterwards, it is discussed how fouling formation can be detected, monitored and characterised, which is essential to implement effective pre-treatment and cleaning strategies. Finally, sustainable ways for preparation of appropriate IEMs are selected and presented.

2019
Ribeiro, SO, Granadeiro CM, Almeida PL, Pires J, Capel-Sanchez MC, Campos-Martin JM, Gago S, de Castro B, Balula SS.  2019.  Oxidative desulfurization strategies using Keggin-type polyoxometalate catalysts: Biphasic versus solvent-free systems, {AUG 1}. Catalysis Today. 333:226-236., Number {SI} AbstractWebsite

Strategic polyoxometalate Keggin-type structural modification was performed to increase the oxidative catalytic performance to desulfurize model and real diesels. The most active lacunar structure {[}PW11O39](7-) (PW11) showed to complete desulfurize a simulated diesel after 60 min at 70 degrees C. Its application as homogeneous catalyst using a biphasic system 1: 1 diesel/acetonitrile needed to use an excess of oxidant (ratio H2O2/S = 8). The immobilization of the PW11 on amine-functionalized SBA-15 supports originated two heterogeneous catalysts PW11@aptesSBA-15 and PW11@tbaSBA-15. The best results were attained with the PW11@aptesSBA-15 catalyst showing identical oxidative desulfurization performance as the homogeneous analogue. As advantage, this heterogeneous catalyst promotes the complete desulfurization of simulated diesel using a solvent-free system, i.e. without the need of acetonitrile use. On the other hand, the same desulfurization efficiency could be achieved using half the amount of oxidant (H2O2/S = 4). The oxidative desulfurization of the real diesel achieved a remarkable 83.4% of efficiency after just 2 h. The recycling capacity of PW11@aptesSBA-15 catalyst was confirmed for eight consecutive cycles using the biphasic and the solvent-free systems. Its stability investigation demonstrates to be higher under the solvent-free system than the biphasic system, without practically any occurrence of PW11 leaching in the first case. On the other hand, the Venturello peroxocomplex {[}PO4\{W(O-2)(2)\}(4)](3-), recognized as active intermediate in the homogeneous biphasic system, was not identified in the heterogeneous catalytic systems.

Kourmentza, C, Araújo D, Sevrin C, Roma-Rodriques C, Ferreira {JL}, Freitas F, Dionisio M, Baptista {PV}, Fernandes {AR}, Grandfils C, Reis {MAM }.  2019.  Occurrence of non-toxic bioemulsifiers during polyhydroxyalkanoate production by Pseudomonas strains valorizing crude glycerol by-product, jun. Bioresource Technology. 281:31–40.: Elsevier Abstract

While screening for polyhydroxyalkanoate (PHA) producing strains, using glycerol rich by-product as carbon source, it was observed that extracellular polymers were also secreted into the culture broth. The scope of this study was to characterize both intracellular and extracellular polymers, produced by Pseudomonas putida NRRL B-14875 and Pseudomonas chlororaphis DSM 50083, mostly focusing on those novel extracellular polymers. It was found that they fall into the class of bioemulsifiers (BE), as they showed excellent emulsion stability against different hydrocarbons/oils at various pH conditions, temperature and salinity concentrations. Cytotoxicity tests revealed that BE produced by P. chlororaphis inhibited the growth of highly pigmented human melanoma cells (MNT-1) by 50% at concentrations between 150 and 200 μg/mL, while no effect was observed on normal skin primary keratinocytes and melanocytes. This is the first study reporting mcl-PHA production by P. putida NRRL B-14785 and bioemulsifier production from both P. putida and P. chlororaphis strains.

Kourmentza, C, Araujo D, Sevrin C, Roma-Rodriques C, Lia Ferreira J, Freitas F, Dionisio M, Baptista PV, Fernandes AR, Grandfils C, Reis MAM.  2019.  Occurrence of non-toxic bioemulsifiers during polyhydroxyalkanoate production by Pseudomonas strains valorizing crude glycerol by-product, 2019. Bioresour Technol. 281:31-40. AbstractWebsite

While screening for polyhydroxyalkanoate (PHA) producing strains, using glycerol rich by-product as carbon source, it was observed that extracellular polymers were also secreted into the culture broth. The scope of this study was to characterize both intracellular and extracellular polymers, produced by Pseudomonas putida NRRL B-14875 and Pseudomonas chlororaphis DSM 50083, mostly focusing on those novel extracellular polymers. It was found that they fall into the class of bioemulsifiers (BE), as they showed excellent emulsion stability against different hydrocarbons/oils at various pH conditions, temperature and salinity concentrations. Cytotoxicity tests revealed that BE produced by P. chlororaphis inhibited the growth of highly pigmented human melanoma cells (MNT-1) by 50% at concentrations between 150 and 200mug/mL, while no effect was observed on normal skin primary keratinocytes and melanocytes. This is the first study reporting mcl-PHA production by P. putida NRRL B-14785 and bioemulsifier production from both P. putida and P. chlororaphis strains.

Kourmentza, C, Araujo D, Sevrinc C, Roma-Rodriques C, Ferreira LJ, Freitas F, Dionísio M, Baptista PV, Fernandes AR, Grandfils C, Reis MAM.  2019.  Occurrence of non-toxic bioemulsifiers during polyhydroxyalkanoate production by Pseudomonas strains valorizing crude glycerol by-product. Bioresource Technology . 281:31-40.Website
Paiva, T, Echeverria C, Godinho MH, Almeida PL, Corvo M.  2019.  On the influence of imidazolium ionic liquids on cellulose derived polymers. European Polymer Journal. : Elsevier AbstractWebsite

The demand for better cellulose solvents has driven the search for new and improved materials to enable the processing of this polysaccharide. Ionic liquids have been debated for a long time as interesting alternatives, but the molecular details on the solubilization mechanism have been a matter of controversy. Herein, for the first time, the structure and dynamics of hydroxypropylcellulose (HPC) liquid crystal solutions were probed in the presence of imidazolium ionic liquids (ILs), conjugating rheological measurements with magnetic resonance spectroscopy. This study provides a characterization of the solutions macroscopic behaviour, where the liquid crystalline (LC) properties were maintained. Using ILs with different side chain lengths, the influence of the hydrophobic IL domain in the solvation abilities of ILs towards a cellulose derived polymer was accessed, providing experimental evidence on these interactions.

Santos, G, Alves C, Pádua AC, Palma S, Gamboa H, Roque ACA.  2019.  An Optimized E-nose for Efficient Volatile Sensing and Discrimination. Proceedings of the 12th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 1: BIODEVICES. , Prague, Czech Republic AbstractPDF

Electronic noses (E-noses), are usually composed by an array of sensors with different selectivities towards classes of VOCs (Volatile Organic Compounds). These devices have been applied to a variety of fields, including environmental protection, public safety, food and beverage industries, cosmetics, and clinical diagnostics. This work demonstrates that it is possible to classify eleven VOCs from different chemical classes using a single gas sensing biomaterial that changes its optical properties in the presence of VOCs. To accomplish this, an in-house built E-nose, tailor-made for the novel class of gas sensing biomaterials, was improved and combined with powerful machine learning techniques. The device comprises a delivery system, a detection system and a data acquisition and control system. It was designed to be stable, miniaturized and easy-to-handle. The data collected was pre-processed and features and curve fitting parameters were extracted from the original response. A recursive feature selection method was applied to select the best features, and then a Support Vector Machine classifier was implemented to distinguish the eleven distinct VOCs. The results show that the followed methodology allowed the classification of all the VOCs tested with 94.6% (± 0.9%) accuracy.

Alexandre, M, Chapa M, Haque S, Mendes MJ, Águas H, Fortunato E, Martins R.  2019.  Optimum Luminescent Down-Shifting Properties for High Efficiency and Stable Perovskite Solar Cells. ACS Applied Energy Materials. 2(4):2930–2938.
Alexandre, M, Chapa M, Haque S, Mendes MJ, Águas H, Fortunato E, Martins R.  2019.  Optimum Luminescent Down-Shifting Properties for High Efficiency and Stable Perovskite Solar Cells. ACS Applied Energy Materials. 2:2930-2938., Number 4 AbstractWebsite

In recent years, the discovery of the excellent optical and electrical properties of perovskite solar cells (PSCs) made them a main focus of research in photovoltaics, with efficiency records increasing astonishingly fast since their inception. However, problems associated with the stability of these devices are hindering their market application. UV degradation is one of the most severe issues, chiefly caused by TiO2’s photogenerated electrons that decompose the perovskite absorber material, coupled with the additional intrinsic degradation of this material under UV exposure. The solution presented here can minimize this effect while boosting the cells’ generated photocurrent, by making use of combined light-trapping and luminescent down-shifting effects capable of changing the harmful UV radiation to higher wavelengths that do not affect the stability and can be effectively “trapped” in the cell. This work focuses in the optimization of the photocurrent gains that can be attained by emulating the changed spectrum resulting from applying down-shifting media as encapsulant in photonic-enhanced PSCs, as well as the reduction in the harmful effects of UV radiation on the devices. Such optimized photonic solution allows current enhancement while reducing the harmful UV photocarrier generation both in the TiO2 (by 1 order of magnitude) and in the perovskite (by 80%) relative to a standard PSC without light management.

2018
Cordeiro, M, Otrelo-Cardoso {ARC}, Svergun {DI }, Konarev {PV }, Lima {JC}, Santos-Silva T, Baptista {PV}.  2018.  Optical and Structural Characterization of a Chronic Myeloid Leukemia DNA Biosensor, may. ACS Chemical Biology. 13:1235–1242., Number 5: ACS - American Chemical Society Abstract

Selective base pairing is the foundation of DNA recognition. Here, we elucidate the molecular and structural details of a FRET-based two-component molecular beacon relying on steady-state fluorescence spectroscopy, small-angle X-ray scattering (SAXS), microscale thermophoresis (MST), and differential electrophoretic mobility. This molecular beacon was designed to detect the most common fusion sequences causing chronic myeloid leukemia, e14a2 and e13a2. The emission spectra indicate that the self-assembly of the different components of the biosensor occurs sequentially, triggered by the fully complementary target. We further assessed the structural alterations leading to the specific fluorescence FRET signature by SAXS, MST, and the differential electrophoretic mobility, where the size range observed is consistent with hybridization and formation of a 1:1:1 complex for the probe in the presence of the complementary target and revelator. These results highlight the importance of different techniques to explore conformational DNA changes in solution and its potential to design and characterize molecular biosensors for genetic disease diagnosis.

Mendes, MJ, Haque S, Sanchez-Sobrado O, Araújo A, Águas H, Fortunato E, Martins R.  2018.  Optimal-Enhanced Solar Cell Ultra-thinning with Broadband Nanophotonic Light Capture, 2018. iScienceiScience. 3:238-254.: Elsevier AbstractWebsite
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Almeida, T.  2018.  O vidro enquanto material e o vidro enquanto arte. Specularis - looking through. (Teresa Almeida, Machado, Graciela, Eds.)., Porto: i2ADS - Instituto de Investigação em Arte, Design e Sociedade Faculdade de Belas Artes da Universidade do Porto