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2021
Boane, Jenny L. N., Pedro Centeno, Ana Mouquinho, Miguel Alexandre, Tomás Calmeiro, Elvira Fortunato, Rodrigo Martins, Manuel J. Mendes, and Hugo Águas. "Soft-Microstructured Transparent Electrodes for Photonic-Enhanced Flexible Solar Cells." Micro. 1 (2021): 215-227. AbstractWebsite

Microstructured transparent conductive oxides (TCOs) have shown great potential as photonic electrodes in photovoltaic (PV) applications, providing both optical and electrical improvements in the solar cells’ performance due to: (1) strong light trapping effects that enhance broadband light absorption in PV material and (2) the reduced sheet resistance of the front illuminated contact. This work developed a method for the fabrication and optimization of wavelength-sized indium zinc oxide (IZO) microstructures, which were soft-patterned on flexible indium tin oxide (ITO)-coated poly(ethylene terephthalate) (PET) substrates via a simple, low-cost, versatile, and highly scalable colloidal lithography process. Using this method, the ITO-coated PET substrates patterned with IZO micro-meshes provided improved transparent electrodes endowed with strong light interaction effects—namely, a pronounced light scattering performance (diffuse transmittance up to  50%). In addition, the photonic-structured IZO mesh allowed a higher volume of TCO material in the electrode while maintaining the desired transparency, which led to a sheet resistance reduction (by  30%), thereby providing further electrical benefits due to the improvement of the contact conductance. The results reported herein pave the way for a new class of photonic transparent electrodes endowed with mechanical flexibility that offer strong potential not only as advanced front contacts for thin-film bendable solar cells but also for a much broader range of optoelectronic applications.

Morgado, Lu{\'ısa M., Magda Rebelo, and Lu{\'ıs L. Ferrás. "Stable and convergent finite difference schemes on nonuniformtime meshes for distributed-order diffusion equations." Mathematics. 9 (2021): 1975. Abstract
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Coronelli, Dario, Marco Lamperti Tornaghi, Luca Martinelli, Francisco-Javier Molina, Aurelio Muttoni, Ion Radu Pascu, Pierre Pegon, Marco Peroni, António Pinho Ramos, Georgios Tsionis, and Teresa Netti. "Testing of a full-scale flat slab building for gravity and lateral loads." Engineering Structures. 243 (2021). AbstractWebsite
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Araújo, João, João Pedro Araújo, Wolfram Bentz, Peter J. Cameron, and Pablo Spiga. "A transversal property for permutation groups motivated by partial transformations." J. Algebra. 573 (2021): 741-759. AbstractWebsite
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Antão, A. N., M. Vicente da Silva, N. Monteiro, and N. Deusdado. "Upper and lower bounds for three-dimensional undrained stability of shallow tunnels." Transportation Geotechnics. 27 (2021): 100491. AbstractWebsite

This paper deals with the determination of upper and lower bounds for the three-dimensional undrained stability of shallow tunnels. The tunnel is circular and a distance between its face and its lining is considered. The soil shear strength is modeled using the Tresca criterion. Results of the upper and lower bounds of the stability number are presented, for several geometrical and resistance configurations and their comparison with previous results is made, showing the clear improvement obtained. Finally, equations approaching the stability number are proposed.

Filipe, Leandro, Ricardo Silva Peres, and Rui Manuel Tavares. "Voice-Activated Smart Home Controller Using Machine Learning." {IEEE} Access (2021): 1. AbstractWebsite
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Ensina, Ana, Patr{\'ıcia M. Carvalho, Jorge Machado, Maria Luisa Carvalho, Diogo Casal, Diogo Pais, José Paulo Santos, António A. Dias, and Sofia Pessanha. "{Analysis of human tissues using Energy Dispersive X Ray Fluorescence ? Dark matrix determination for the application to cancer research}." Journal of Trace Elements in Medicine and Biology. 68 (2021): 126837. AbstractWebsite

Journal of Trace Elements in Medicine and Biology, 68 (2021) 126837. doi:10.1016/j.jtemb.2021.126837

Cruz, J., M. Fonseca, D. Galaviz, A. Henriques, H. Lu{\'ıs, J. Machado, P. Teubig, P. Velho, V. Manteigas, and A. P. Jesus. "{Fluorine depth profiling based on the 19F(p,p’$\gamma$)19F excitation function}." The European Physical Journal Plus. 136 (2021): 1-12. AbstractWebsite

Ion beam analysis of fluorine has applications in research on teeth and bones, materials science, geochemistry and archaeometry. A novel PIGE (particle induced gamma-ray emission) standard free methodology for fluorine content determination for in-depth heterogeneous samples based on the excitation function of the 19F(p,p’$\gamma$)19F nuclear reaction is presented. New precise cross section measurements of this reaction in the proton energy range 2.1 to 4.1 MeV have been performed. In addition, the ERYA-Profiling code, a computer program specially developed for PIGE analysis of in-depth heterogeneous samples, employed this new excitation function in a case study where different fluorine simulated depth profiles probed the capability of insight into fluorine distributions in a given sample, showing the potential of PIGE analysis.

{Guerra, Mauro, Jorge Sampaio, Gon{\c c}alo V{\'ılia, César Godinho, Daniel Pinheiro, Pedro Amaro, José Marques, Jorge Machado, Paul Indelicato, Fernando Parente, and José Santos. "{Fundamental Parameters Related to Selenium K$\alpha$ and K$\beta$ Emission X-ray Spectra}." Atoms. 9 (2021): 8-10. AbstractWebsite

We present relativistic ab initio calculations of fundamental parameters for atomic selenium, based on the Multiconfiguration Dirac-Fock method. In detail, fluorescence yields and subshell linewidths, both of K shell, as well as K$\beta$ to K$\alpha$ intensity ratio are provided, showing overall agreement with previous theoretical calculations and experimental values. Relative intensities were evaluated assuming the same ionization cross-section for the K-shell hole states, leading to a statistical distribution of these initial states. A method for estimating theoretical linewidths of X-ray lines, where the lines are composed by a multiplet of fine-structure levels that are spread in energy, is proposed. This method provides results that are closer to K$\alpha$1,2 experimental width values than the usual method, although slightly higher discrepancies occur for the K$\beta$1,3 lines. This indicates some inaccuracies in the calculation of Auger rates that have a higher contribution for partial linewidths of the subshells involved in the K$\beta$1,3 profile. Apart from this, the calculated value of K$\beta$ to K$\alpha$ intensity ratio, which is less sensitive to Auger rates issues, is in excellent agreement with recommended values.

Boretzky, K., I. Gasparic, M. Heil, J. Mayer, A. Heinz, C. Caesar, D. Kresan, H. Simon, H. T. Törnqvist, D. Körper, G. Alkhazov, L. Atar, T. Aumann, D. Bemmerer, S. V. Bondarev, L. T. Bott, S. Chakraborty, M. I. Cherciu, L. V. Chulkov, M. Ciobanu, U. Datta, E. De Filippo, C. A. Douma, J. Dreyer, Z. Elekes, J. Enders, D. Galaviz, E. Geraci, B. Gnoffo, K. Göbel, V. L. Golovtsov, Gonzalez D. Diaz, N. Gruzinsky, T. Heftrich, H. Heggen, J. Hehner, T. Hensel, E. Hoemann, M. Holl, A. Horvat, Á. Horváth, G. Ickert, Jelavić D. Malenica, H. T. Johansson, B. Jonson, J. Kahlbow, N. Kalantar-Nayestanaki, A. Kelic-Heil, M. Kempe, K. Koch, N. G. Kozlenko, A. G. Krivshich, N. Kurz, V. Kuznetsov, C. Langer, Y. Leifels, I. Lihtar, B. Löher, J. Machado, N. S. Martorana, K. Miki, T. Nilsson, E. M. Orischin, E. V. Pagano, S. Pirrone, G. Politi, P. M. Potlog, A. Rahaman, R. Reifarth, C. Rigollet, M. Röder, D. M. Rossi, P. Russotto, D. Savran, H. Scheit, F. Schindler, D. Stach, E. Stan, Stomvall J. Gill, P. Teubig, M. Trimarchi, L. Uvarov, M. Volknandt, S. Volkov, A. Wagner, V. Wagner, S. Wranne, D. Yakorev, L. Zanetti, A. Zilges, K. Zuber, and R. 3B. collaboration. "{NeuLAND: The high-resolution neutron time-of-flight spectrometer for R3B at FAIR}." Nuclear Inst. and Methods in Physics Research, A. 1014 (2021): 165701. AbstractWebsite

Nuclear Inst. and Methods in Physics Research, A, 1014 (2021) 165701. doi:10.1016/j.nima.2021.165701

Goodfellow, Brian J., Filipe Freire, Ana Luísa Carvalho, Susana S. Aveiro, Peggy Charbonnier, Jean-Marc Moulis, Leonildo Delgado, Gloria C. Ferreira, João E. Rodrigues, Pierre Poussin-Courmontagne, Catherine Birck, Alastair McEwen, and Anjos L. Macedo. "{The SOUL family of heme-binding proteins: Structure and function 15 years later}." Coordination Chemistry Reviews. 448 (2021): 214189. AbstractWebsite

The SOUL, or heme-binding protein HBP/SOUL, family represents a group of evolutionary conserved putative heme-binding proteins that contains a number of members in animal, plant andbacterial species. The structures of the murine form of HEBP1, or p22HBP, and the human form of HEBP2, or SOUL, have been determined in 2006 and 2011 respectively. In this work we discuss the structures of HEBP1 and HEBP2 in light of new X-ray data for heme bound murine HEBP1. The interaction between tetrapyrroles and HEBP1, initially proven to be hydrophobic in nature, was thought to also involve electrostatic interactions between heme propionate groups and positively charged amino acid side chains. However, the new X-ray structure, and results from murine HEBP1 variants and human HEBP1, confirm the hydrophobic nature of the heme-HEBP1 interaction, resulting in Kd values in the low nanomolar range, and rules out any electrostatic stabilization. Results from NMR relaxation time measurements for human HEBP1 describe a rigid globular protein with no change in motional regime upon heme binding. X-ray structures deposited in the PDB for human HEBP2 are very similar to each other and to the new heme-bound murine HEBP1 X-ray structure (backbone rmsd ca. 1 {\AA}). Results from a HSQC spectrum centred on the histidine side chain N$δ$-proton region for HEBP2 confirm that HEBP2 does not bind heme via H42 as no chemical shift differences were observed upon heme addition for backbone NH and N$δ$ protons. A survey of the functions attributed to HEBP1 and HEBP2 over the last 20 years span a wide range of cellular pathways. Interestingly, many of them are specific to higher eukaryotes, particularly mammals and a potential link between heme release under oxidative stress and human HEBP1 is also examined using recent data. However, at the present moment, trying to relate function to the involvement of heme or tetrapyrrole binding, specifically, makes little sense with our current biological knowledge and can only be applied to HEBP1, as HEBP2 does not interact with heme. We suggest that it may not be justified to call this very small family of proteins, heme-binding proteins. The family may be more correctly called “the SOUL family of proteins related to cellular fate” as, even though only HEBP1 binds heme tightly, both proteins may be involved in cell survival and/or proliferation.

2020
Syndikus, I., M. Petri, A. O. Macchiavelli, S. Paschalis, C. A. Bertulani, T. Aumann, H. Alvarez-Pol, L. Atar, S. Beceiro-Novo, J. Benlliure, J. M. Boillos, K. Boretzky, M. J. G. Borge, B. A. Brown, M. Caamano, C. Caesar, E. Casarejos, W. Catford, J. Cederkäll, S. Chakraborty, L. V. Chulkov, D. Cortina-Gil, E. Cravo, R. Crespo, Datta U. Pramanik, I. Dillmann, Diaz P. Fernandez, Z. Elekes, J. Enders, F. Farinon, L. M. Fraile, D. Galaviz, H. Geissel, R. Gernhäuser, P. Golubev, K. Göbel, M. Heil, M. Heine, A. Heinz, A. Henriques, M. Holl, H. T. Johansson, B. Jonson, N. Kalantar-Nayestanaki, R. Kanungo, A. Kelic-Heil, T. Kröll, N. Kurz, C. Langer, T. Le Bleis, J. Machado, J. Marganiec-Gałązka, E. Nacher, T. Nilsson, C. Nociforo, V. Panin, A. Perea, S. B. Pietri, R. Plag, A. Rahaman, R. Reifarth, A. Revel, G. Ribeiro, C. Rigollet, D. M. Rossi, D. Savran, H. Scheit, H. Simon, O. Sorlin, O. Tengblad, Y. Togano, M. Vandebrouck, V. Volkov, F. Wamers, C. Wheldon, G. L. Wilson, J. S. Winfield, H. Weick, P. Woods, D. Yakorev, M. Zhukov, A. Zilges, K. Zuber, and R. 3B. collaboration. "{Probing the Z=6 spin-orbit shell gap with (p,2p) quasi-free scattering reactions}." Physics Letters B. 809 (2020): 135748. AbstractWebsite

Physics Letters B, 809 (2020) 135748. 10.1016/j.physletb.2020.135748

Mateus, Ayana, and Frederico Caeiro. "A new class of estimators for the shape parameter of a Pareto model." Computational and Mathematical Methods (2020). AbstractWebsite
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Togawa, M., S. Kühn, C. Shah, P. Amaro, R. Steinbrügge, J. Stierhof, N. Hell, M. Rosner, K. Fujii, M. Bissinger, R. Ballhausen, M. Hoesch, J. Seltmann, S. Park, F. Grilo, F. S. Porter, J. P. Santos, M. Chung, T. Stöhlker, J. Wilms, T. Pfeifer, G. V. Brown, M. A. Leutenegger, S. Bernitt, and Crespo J. R. López-Urrutia. "Observation of strong two-electron–one-photon transitions in few-electron ions." Physical Review A. 102 (2020). AbstractWebsite
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Ito, Y., T. Tochio, M. Yamashita, S. Fukushima, A. M. Vlaicu, J. P. Marques, J. M. Sampaio, M. Guerra, J. P. Santos, Ł. Syrocki, K. Słabkowska, E. WÈ©der, M. Polasik, J. Rzadkiewicz, P. Indelicato, Y. Ménesguen, M.-Ch. Lépy, and F. Parente. "Structure of K$\upalpha$1,2- and K$\upbeta$1,3-emission x-ray spectra for Se, Y, and Zr." Physical Review A. 102 (2020). AbstractWebsite
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Caeiro, Frederico, L{\'ı}gia Henriques-Rodrigues, Ivette M. Gomes, and Ivanilda Cabral. "Minimum-variance reduced-bias estimation of the extreme value index: A theoretical and empirical study." Computational and Mathematical Methods (2020). AbstractWebsite
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Murugesan, Gavuthami, Viviana G. Correia, Angelina S. Palma, Wengang Chai, Chunxia Li, Ten Feizi, Eva Martin, Brigitte Laux, Alexandra Franz, Klaus Fuchs, Bernd Weigle, and Paul R. Crocker. "Siglec-15 recognition of sialoglycans on tumor cell lines can occur independently of sialyl Tn antigen expression." Glycobiology (2020). Abstract

Siglec-15 is a conserved sialic acid-binding Ig-like lectin expressed on osteoclast progenitors that plays an important role in osteoclast development and function. It is also expressed by tumor-associated macrophages and by some tumors, where it is thought to contribute to the immunosuppressive microenvironment. It was shown previously that engagement of macrophage-expressed Siglec-15 with tumor cells expressing its ligand, sialyl Tn (sTn), triggered production of TGF-$\beta$. In the present study, we have further investigated the interaction between Siglec-15 and sTn on tumor cells and its functional consequences. Based on binding assays with lung and breast cancer cell lines and glycan-modified cells, we failed to see evidence for recognition of sTn by Siglec-15. However, using a microarray of diverse, structurally-defined glycans, we show that Siglec-15 binds with higher avidity to sialylated glycans other than sTn or related antigen sequences. In addition, we were unable to demonstrate enhanced TGF-$\beta$ secretion following co-culture of Siglec-15-expressing monocytic cells lines with tumor cells expressing sTn, or following Siglec-15 cross-linking with monoclonal antibodies. However, we did observe activation of the SYK/MAPK signaling pathway following antibody cross-linking of Siglec-15 that may modulate the functional activity of macrophages.

Ribeiro, Diana O., Aldino Viegas, Virgínia M. R. Pires, João Medeiros-Silva, Pedro Bule, Wengang Chai, Filipa Marcelo, Carlos M. G. A. Fontes, Eurico J. Cabrita, Angelina S. Palma, and Ana Luísa Carvalho. "Molecular basis for the preferential recognition of beta 1,3-1,4-glucans by the family 11 carbohydrate-binding module from Clostridium thermocellum." The FEBS journal. 287 (2020): 2723-2743. Abstract

Understanding the specific molecular interactions between proteins and $\beta$1,3-1,4-mixed-linked d-glucans is fundamental to harvest the full biological and biotechnological potential of these carbohydrates and of proteins that specifically recognize them. The family 11 carbohydrate-binding module from Clostridium thermocellum (CtCBM11) is known for its binding preference for $\beta$1,3-1,4-mixed-linked over $\beta$1,4-linked glucans. Despite the growing industrial interest of this protein for the biotransformation of lignocellulosic biomass, the molecular determinants of its ligand specificity are not well defined. In this report, a combined approach of methodologies was used to unravel, at a molecular level, the ligand recognition of CtCBM11. The analysis of the interaction by carbohydrate microarrays and NMR and the crystal structures of CtCBM11 bound to $\beta$1,3-1,4-linked glucose oligosaccharides showed that both the chain length and the position of the $\beta$1,3-linkage are important for recognition, and identified the tetrasaccharide Glc$\beta$1,4Glc$\beta$1,4Glc$\beta$1,3Glc sequence as a minimum epitope required for binding. The structural data, along with site-directed mutagenesis and ITC studies, demonstrated the specificity of CtCBM11 for the twisted conformation of $\beta$1,3-1,4-mixed-linked glucans. This is mediated by a conformation-selection mechanism of the ligand in the binding cleft through CH-$π$ stacking and a hydrogen bonding network, which is dependent not only on ligand chain length, but also on the presence of a $\beta$1,3-linkage at the reducing end and at specific positions along the $\beta$1,4-linked glucan chain. The understanding of the detailed mechanism by which CtCBM11 can distinguish between linear and mixed-linked $\beta$-glucans strengthens its exploitation for the design of new biomolecules with improved capabilities and applications in health and agriculture. DATABASE: Structural data are available in the Protein Data Bank under the accession codes 6R3M and 6R31.

Duarte, Susana, {Maria Rosário} do Cabrita, and V. Cruz-Machado. "Business model, lean and green management and industry 4.0: A conceptual relationship." Proceedings of the 13th International Conference on Management Science and Engineering Management, 2019 - Volume 1. Eds. Jiuping Xu, Gheorghe Duca, {Fang Lee } Cooke, and {Syed Ejaz } Ahmed. Advances in Intelligent Systems and Computing. Germany: Springer Verlag, 2020. 359-372. Abstract

The Industry 4.0 addresses a radical change on business processes. Through communication technology, objects interact with each other; the physical and digital worlds merge. This makes an environment more flexible, allowing to respond faster to specific customer requirements. Therefore, businesses need to rapidly adapt to avoid being left behind. A business model is required to meet the new concepts of Industry 4.0. In addition, lean and green characteristics may align with business model elements. Understanding how these concepts interact is something that need clarification. Based on literature review, a conceptual relationship between Business Model (Canvas), Lean and green management approach and Industry 4.0 approach is presented. Lean and green management characteristics are identified to be aligned through a Business Model Canvas perspective. Also, the concepts of the Industry 4.0 can be applied in each element of the Business Model Canvas. Managers and entrepreneurs can create, design or redefine their business knowing the lean and green application and Industry 4.0 execution. This research aims to contribute to the discussion of the relationships between these concepts. To the authors’ knowledge, this work is one of the first to try to relate these concepts.

Vendele, Ingrida, Janet A. Willment, Lisete M. Silva, Angelina S. Palma, Wengang Chai, Yan Liu, Ten Feizi, Maria Spyrou, Mark H. T. Stappers, Gordon D. Brown, and Neil A. R. Gow. "{Mannan detecting C-type lectin receptor probes recognise immune epitopes with diverse chemical, spatial and phylogenetic heterogeneity in fungal cell walls.}." PLoS pathogens. 16 (2020): e1007927. Abstract

During the course of fungal infection, pathogen recognition by the innate immune system is critical to initiate efficient protective immune responses. The primary event that triggers immune responses is the binding of Pattern Recognition Receptors (PRRs), which are expressed at the surface of host immune cells, to Pathogen-Associated Molecular Patterns (PAMPs) located predominantly in the fungal cell wall. Most fungi have mannosylated PAMPs in their cell walls and these are recognized by a range of C-type lectin receptors (CTLs). However, the precise spatial distribution of the ligands that induce immune responses within the cell walls of fungi are not well defined. We used recombinant IgG Fc-CTLs fusions of three murine mannan detecting CTLs, including dectin-2, the mannose receptor (MR) carbohydrate recognition domains (CRDs) 4-7 (CRD4-7), and human DC-SIGN (hDC-SIGN) and of the $\beta$-1,3 glucan-binding lectin dectin-1 to map PRR ligands in the fungal cell wall of fungi grown in vitro in rich and minimal media. We show that epitopes of mannan-specific CTL receptors can be clustered or diffuse, superficial or buried in the inner cell wall. We demonstrate that PRR ligands do not correlate well with phylogenetic relationships between fungi, and that Fc-lectin binding discriminated between mannosides expressed on different cell morphologies of the same fungus. We also demonstrate CTL epitope differentiation during different phases of the growth cycle of Candida albicans and that MR and DC-SIGN labelled outer chain N-mannans whilst dectin-2 labelled core N-mannans displayed deeper in the cell wall. These immune receptor maps of fungal walls of in vitro grown cells therefore reveal remarkable spatial, temporal and chemical diversity, indicating that the triggering of immune recognition events originates from multiple physical origins at the fungal cell surface.

Martins, L., P. Amaro, S. Pessanha, M. Guerra, J. Machado, M. L. Carvalho, J. P. Santos, and P. Indelicato. "{Overview and calculation of X-ray K-shell transition yields for comprehensive data libraries}." X-Ray Spectrom.. 62 (2020): 63-26. AbstractWebsite

The simulation of atomic relaxation relies on data libraries with tabulated partial fluorescence yield values of radiative transitions, commonly derived from the Evaluated Atomic Data Library (EADL)....

Machado, Jorge, {Patrícia M. S. } Carvalho, Ana Félix, Delfin Doutel, {José Paulo} Santos, {Maria Luísa} Carvalho, and Sofia Pessanha. "Accuracy improvement in XRF analysis for the quantification of elements ranging from tenths to thousands μg g-1in human tissues using different matrix reference materials." Journal of Analytical Atomic Spectrometry. 35 (2020): 2920-2927. Abstract

In this work, we aim at achieving the most accurate quantitative determination of elements in human tissues by means of X-ray Fluorescence spectrometry using the external calibration approach. A calibration curve built using a set of certified reference materials (CRM) of animal tissue was compared with the one obtained with a set of CRMs of plants and leaves with lower atomic number Z but with correction of the matrix using the scattering peaks of the X-ray tube anode. Finally, a calibration curve combining the two sets of CRMs was built and the accuracy of the quantification using the three methods was compared and a more precise method of quantification was obtained. This improved approach was tested on five paired samples of normal and tumour human tissue. Despite the high heterogeneity of the samples, and given the improvement in accuracy of the measurements, significant differences were found in the elemental concentration of low-Z elements. This journal is

Carvalho, Patr{\'ı}cia M. S., Sofia Pessanha, Jorge Machado, Ana Lu{\'ı}sa Silva, João Veloso, Diogo Casal, Diogo Pais, and José Paulo Santos. "Energy dispersive X-ray fluorescence quantitative analysis of biological samples with the external standard method." Spectrochimica Acta Part B: Atomic Spectroscopy. 174 (2020): 105991. AbstractWebsite
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Carvalho, Patr{\'ıcia M. S., Sofia Pessanha, Jorge Machado, Ana Lu{\'ısa Silva, João Veloso, Diogo Casal, Diogo Pais, and José Paulo Santos. "{Energy dispersive X-ray fluorescence quantitative analysis of biological samples with the external standard method}." Spectrochimica Acta Part B: Atomic Spectroscopy. 174 (2020): 105991. AbstractWebsite
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Martins, Jorge, Asal Kiazadeh, Joana V. Pinto, Ana Rovisco, Tiago Gonçalves, Jonas Deuermeier, Eduardo Alves, Rodrigo Martins, Elvira Fortunato, and Pedro Barquinha. "{Ta2O5/SiO2 Multicomponent Dielectrics for Amorphous Oxide TFTs}." Electronic Materials. 2 (2020): 1-16. AbstractWebsite

Co-sputtering of SiO2 and high-$ąppa$ Ta2O5 was used to make multicomponent gate dielectric stacks for In-Ga-Zn-O thin-film transistors (IGZO TFTs) under an overall low thermal budget (T = 150 °C). Characterization of the multicomponent layers and of the TFTs working characteristics (employing them) was performed in terms of static performance, reliability, and stability to understand the role of the incorporation of the high-$ąppa$ material in the gate dielectric stack. It is shown that inherent disadvantages of the high-$ąppa$ material, such as poorer interface properties and poor gate insulation, can be counterbalanced by inclusion of SiO2 both mixed with Ta2O5 and as thin interfacial layers. A stack comprising a (Ta2O5)x(SiO2)100 − x film with x = 69 and a thin SiO2 film at the interface with IGZO resulted in the best performing TFTs, with field-effect mobility (µFE) ≈ 16 cm2·V−1·s−1, subthreshold slope (SS) ≈ 0.15 V/dec and on/off ratio exceeding 107. Anomalous Vth shifts were observed during positive gate bias stress (PGBS), followed by very slow recoveries (time constant exceeding 8 × 105 s), and analysis of the stress and recovery processes for the different gate dielectric stacks showed that the relevant mechanism is not dominated by the interfaces but seems to be related to the migration of charged species in the dielectric. The incorporation of additional SiO2 layers into the gate dielectric stack is shown to effectively counterbalance this anomalous shift. This multilayered gate dielectric stack approach is in line with both the large area and the flexible electronics needs, yielding reliable devices with performance suitable for successful integration on new electronic applications.