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2021
Gigante, AM, Olivença F, Catalão MJ, Moniz-Pereira J, Filipe SR, Pimentel M.  2021.  The Mycobacteriophage Ms6 LysB N-terminus Displays Peptidoglycan Binding Affinity. Viruses. 13(7):1377.
Graça, MP, Teixeira SS, Gavinho SR, Valente MA, Salgueiro C, Nunes J, Soares PIP, Lança MC, Vieira T, Silva JC, Borges JB.  2021.  Nanomaterials for magnetic hyperthermia. European Journal of Public Health. 31(Supplement_2):ckab120.066. AbstractWebsite

Cancer remains as one of the major causes of mortality worldwide. Recent advances in nanoparticles based therapy mark a new era on cancer treatment. Many groups have investigated biological/physical effects of nanoparticles on tumour cells and how these vary with physical parameters such as particle size, shape, concentration and distribution. Magnetic hyperthermia (MHT) can be an alternative or an add-value therapy with demonstrated effectiveness. MHT uses magnetic nanoparticles, which can be directly applied to the tumour, where, by applying an external ac magnetic field, will promote a localized temperature increment that can be controlled.

Teixeira, SS, Graça MPF, Lucas J, Valente MA, Soares PIP, Lança MC, Vieira T, Silva JC, Borges JP, Jinga L-I, Socol G, Salgueiro CM, Nunes J, Costa LC.  2021.  Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine. Nanomaterials. 11(1):193. AbstractWebsite

The physical properties of the cubic and ferrimagnetic spinel ferrite LiFe5O8 has made it an attractive material for electronic and medical applications. In this work, LiFe5O8 nanosized crystallites were synthesized by a novel and eco-friendly sol-gel process, by using powder coconut water as a mediated reaction medium. The dried powders were heat-treated (HT) at temperatures between 400 and 1000 °C, and their structure, morphology, electrical and magnetic characteristics, cytotoxicity, and magnetic hyperthermia assays were performed. The heat treatment of the LiFe5O8 powder tunes the crystallite sizes between 50 nm and 200 nm. When increasing the temperature of the HT, secondary phases start to form. The dielectric analysis revealed, at 300 K and 10 kHz, an increase of ε′ (≈10 up to ≈14) with a tanδ almost constant (≈0.3) with the increase of the HT temperature. The cytotoxicity results reveal, for concentrations below 2.5 mg/mL, that all samples have a non-cytotoxicity property. The sample heat-treated at 1000 °C, which revealed hysteresis and magnetic saturation of 73 emu g−1 at 300 K, showed a heating profile adequate for magnetic hyperthermia applications, showing the potential for biomedical applications.

Bianchi, C, Marques AC, da Silva RC, Calmeiro T, Ferreira I.  2021.  Near infrared photothermoelectric effect in transparent AZO/ITO/Ag/ITO thin films. Scientific reports. 11:1-11.
Carvalho, G, Pereira M, Kiazadeh A, Tavares VG.  2021.  A Neural Network Approach towards Generalized Resistive Switching Modelling. Micromachines. 12(9):1132.
Tipa, C, Cidade MT, Vieira T, Silva JC, Soares PIP, Borges JP.  2021.  A New Long-Term Composite Drug Delivery System Based on Thermo-Responsive Hydrogel and Nanoclay. Nanomaterials. 11(1):25. AbstractWebsite

Several problems and limitations faced in the treatment of many diseases can be overcome by using controlled drug delivery systems (DDS), where the active compound is transported to the target site, minimizing undesirable side effects. In situ-forming hydrogels that can be injected as viscous liquids and jellify under physiological conditions and biocompatible clay nanoparticles have been used in DDS development. In this work, polymer–clay composites based on Pluronics (F127 and F68) and nanoclays were developed, aiming at a biocompatible and injectable system for long-term controlled delivery of methylene blue (MB) as a model drug. MB release from the systems produced was carried out at 37 °C in a pH 7.4 medium. The Pluronic formulation selected (F127/F68 18/2 wt.%) displayed a sol/gel transition at approx. 30 °C, needing a 2.5 N force to be injected at 25 °C. The addition of 2 wt.% of Na116 clay decreased the sol/gel transition to 28 °C and significantly enhanced its viscoelastic modulus. The most suitable DDS for long-term application was the Na116-MB hybrid from which, after 15 days, only 3% of the encapsulated MB was released. The system developed in this work proved to be injectable, with a long-term drug delivery profile up to 45 days.

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.
Mouquinho, A, Sanchez-Sobrado O, Haque S, Centeno P, Alexandre MF, Ribeiro G, Boane JLN, Mateus T, Menda UD, Águas H, Fortunato E, Martins R, Mendes MJ.  2021.  Photonic Strategies for Photovoltaics: New Advances Beyond Optics. Modern Environmental Science and Engineering. 7(7):642-652.
Matos, MJB, Trovão F, Gonçalves J, Rothbauer U, Freire MG, Barbosa AMJB, Pina AS, Roque ACA.  2021.  A purification platform for antibodies and derived fragments using a de novo designed affinity adsorbent. Separation and Purification Technology. 265
Mota, ACC.  2021.  Real-time droplet monitoring for digital Polymerase Chain Reaction in microfluidic chip. Faculdade de Ciências e Tecnologia. (Joana Neto, Hugo Águas, Eds.)., Caparica: Faculdade de Ciências e Tecnologia Abstract

Current cancer diagnosis techniques are often dependent on the collection of tumour tissue, involving invasive processes for the patient. Circulating Tumour DNA (ctDNA) emerges as an alternative resource for cancer detection and monitoring, that can be har vested from simple blood samples. Digital Polymerase Chain Reaction (dPCR) is a fast and sensitive technique for DNA amplification, suitable for low DNA concentrations such as ctDNA. Advances in microfluidics allow the partition of PCR samples into droplets based in water-in-oil emulsions, so that PCR amplification occurs within each droplet. In this way, the PCR reaction is a well controlled process with a low probability of contami nation and allowing a high throughput analysis. The aimed of this work was to develop droplet-based microfluidic device for application to dPCR technique coupled with real-time droplet monitoring. This work focused on the design and fabrication of a microfluidic device capable of producing a large number of uniform droplets with volumes in the nanoliter range and constant frequency. For this, a polydimethylsiloxane (PDMS) droplet generator device was developed, through photo and soft-lithography techniques, and tested with several oil/water flow rates ratios. Then, the droplets generated were characterized in terms of droplet size, velocity and frequency through the implementation of a powerful open-source software for real-time analysis. Several tests on different devices were carried out to evaluate the device reproducibility. Finally, the droplet generator was incorporated with a serpentine design, allowing the PCR cycles to occur in continuous flow. The results revealed that was possible to generate droplets with radius between 22-99 µm and a coefficient of variation bellow 10%. The correspondents volumes ranged between 90 pL-4.18 nL. Moreover, the velocities obtained situated between 0.05 mm/s-7.62 mm/s with droplet generating frequency of 2-50 Hz. Regarding to the droplet monitoring, the results of the workflows developed revealed similarity with the results obtained trough a widely used software for this purposes, with the advantage of allowing real-time analysis for a larger sample of results.

Carlos, E, Branquinha R, Martins R, Kiazadeh A, Fortunato E.  2021.  Recent Progress in Solution‐Based Metal Oxide Resistive Switching Devices. Advanced Material. 33(7):2004328.
Peyroteo, M, Ferreira IA, Elvas LB, Ferreira JC, Lapão LV.  2021.  Remote Monitoring Systems for Patients With Chronic Diseases in Primary Health Care: Systematic Review. JMIR Mhealth and Uhealth. 9(12):1-11.
Isufi, B, Ramos AP.  2021.  A review of tests on slab-column connections with advanced concrete materials. Structures. 32(August 2021):849-860. AbstractWebsite

Advances in concrete technology during the last decades have resulted in the development of materials with enhanced mechanical properties, such as High Strength Concrete (HSC), Fibre Reinforced Concrete (FRC) and Ultra-High Performance Fibre Reinforced Concrete (UHPFRC). The application of these materials in flat slabs, which are a popular structural solution in Reinforced Concrete (RC) buildings worldwide, has the potential of significantly reducing raw material consumption by enabling the design of slenderer and therefore lighter structures. However, flat slabs are susceptible to punching shear failure, which is a complex phenomenon that remains challenging, even though significant efforts have been made to experimentally study it. For advanced concrete materials (HSC, FRC and UHPFRC), the challenge is further accentuated by the continuous and rapid development of these materials. With the purpose of identifying and highlighting gaps in the published literature, a review of tests with HSC, FRC and UHPFRC slab-column connections in non-seismic and seismic loading applications is presented in this paper. It is shown that future research directions in this field include, among others, testing thicker slabs, HSC slabs with higher concrete compressive strength, HSC combined with FRC and several more cases related to seismic loading conditions.

Nunes, MJ, Cordas CM, Moura JJG, Noronha JP, Branco LC.  2021.  Screening of Potential Stress Biomarkers in Sweat Associated with Sports Training. Sports Medicine - Open. 7:8.
El-Haouzi, HB, Valette E, Krings B-J, Moniz AB.  2021.  Social Dimensions in CPS & IoT Based Automated Production Systems. Societies. 11(98)Website
Boane, JLN, Centeno P, Mouquinho A, Alexandre M, Calmeiro T, Fortunato E, Martins R, Mendes MJ, Águas H.  2021.  Soft-Microstructured Transparent Electrodes for Photonic-Enhanced Flexible Solar Cells. Micro. 1(2):215-227.
Ramou, E, Rebordao G, Palma SICJ, Roque ACA.  2021.  Stable and Oriented Liquid Crystal Droplets Stabilized by Imidazolium Ionic Liquids. MOLECULES. 26(19):6044.PDF
Sine, AG.  2021.  STRENGTHENING OF REINFORCED CONCRETE ELEMENTS WITH UHPFRC. Faculty of Engineering of the University of Porto. (Mário Pimentel, Sandra Nunes, Américo Dimande, Eds.)., Portostrengthening_of_rc_elements_with_uhpfrc_agsine.pdf
Shlapa, Y, Timashkov I, Veltruska K, Siposova K, Garcarova I, Musatov A, Solopan S, Kubovcikova M, Belous A.  2021.  Structural and Physical-Chemical Characterization of Redox Active CeO2 Nanoparticles Synthesized by the Precipitation in the Water-Alcohol Solutions. Nanotechnology. 32(315706 )
Moniz, AB, Krings B-J, Frey P.  2021.  Technology as enabler of the automation of work? Current societal challenges for a future perspective of work Revista Brasileira de Sociologia. 2021(9)Website