Export 881 results:
Sort by: Author Title Type [ Year  (Desc)]
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
n/a
2020
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
n/a
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.

Gomes, Ana Sara, Helena Ramos, Sara Gomes, Joana B. Loureiro, Joana Soares, Valentina Barcherini, Paola Monti, Gilberto Fronza, Carla Oliveira, Lucília Domingues, Margarida Bastos, Daniel F. A. R. Dourado, Ana Luísa Carvalho, Maria João Romão, Benedita Pinheiro, Filipa Marcelo, Alexandra Carvalho, Maria M. M. Santos, and Lucília Saraiva. "SLMP53-1 interacts with wild-type and mutant p53 DNA-binding domain and reactivates multiple hotspot mutations." 1864.1 (2020): 129440. AbstractWebsite

BackgroundHalf of human cancers harbour TP53 mutations that render p53 inactive as a tumor suppressor. As such, reactivation of mutant (mut)p53 through restoration of wild-type (wt)-like function represents one of the most promising therapeutic strategies in cancer treatment. Recently, we have reported the (S)-tryptophanol-derived oxazoloisoindolinone SLMP53-1 as a new reactivator of wt and mutp53 R280K with in vitro and in vivo p53-dependent antitumor activity. The present work aimed a mechanistic elucidation of mutp53 reactivation by SLMP53-1.
Methods and results
By cellular thermal shift assay (CETSA), it is shown that SLMP53-1 induces wt and mutp53 R280K thermal stabilization, which is indicative of intermolecular interactions with these proteins. Accordingly, in silico studies of wt and mutp53 R280K DNA-binding domain with SLMP53-1 unveiled that the compound binds at the interface of the p53 homodimer with the DNA minor groove. Additionally, using yeast and p53-null tumor cells ectopically expressing distinct highly prevalent mutp53, the ability of SLMP53-1 to reactivate multiple mutp53 is evidenced.
Conclusions
SLMP53-1 is a p53-activating agent with the ability to directly target wt and a set of hotspot mutp53.
General Significance
This work reinforces the encouraging application of SLMP53-1 in the personalized treatment of cancer patients harboring distinct p53 status.

Fernandes, Cláudio A., and Alexei Yu. Karlovich. "Semi-almost periodic Fourier multipliers on rearrangement-invariant spaces with suitable Muckenhoupt weights." Boletín de la Sociedad Matemática Mexicana. 26.3 (2020): 1135-1162.Website
Torabian, Ala, Brisid Isufi, Davood Mostofinejad, and António Pinho Ramos. "Shear and flexural strengthening of deficient flat slabs with post-installed bolts and CFRP composites bonded through EBR and EBROG." Structural Concrete. n/a (2020). AbstractWebsite

Abstract Fiber reinforced polymer (FRP) composites can be efficient for flexural strengthening of flat slabs if debonding of the FRP is postponed. However, with the increase of the flexural capacity, the flat slab becomes more susceptible to punching shear failure. In this context, four flexural or simultaneous flexural and punching shear retrofitting systems are investigated in this study to strengthen a flexure-deficient flat slab. Externally Bonded Reinforcement on Grooves (EBROG) and externally bonded reinforcement (EBR) methods are used for flexural strengthening in two cases: slabs without punching shear reinforcement and with post-installed shear bolts as shear reinforcement. According to the results, flexural strengthening of the slab using the EBR and EBROG techniques increased its load capacity by 12% and 21%, respectively. Simultaneous flexural and shear strengthening of the slab using the EBROG technique was the most effective, leading to a 57% enhancement of the load capacity. For specimens whose failure was governed by punching, comparing the results with code predictions showed that Eurocode and ACI (and the respective guide documents fib bulletin 90 and ACI 440.2R) overestimated the capacity of these specimens. In cases where failure was governed by flexure, a simple application of the yield line theory predicted reasonably well the load capacity of the specimens.

Torres, D., C. Pimentel, and S. Duarte. "Shop floor management system in the context of smart manufacturing: a case study." International Journal of Lean Six Sigma,. 11.5 (2020): 837-862.
Coronelli, Dario, Aurelio Muttoni, Ion R. Pascu, Antonio P. Ramos, and Teresa Netti. "A state of the art of flat-slab frame tests for gravity and lateral loading." Structural Concrete. n/a (2020). AbstractWebsite

Abstract This paper presents a critical review of the state of the art of experimental research concerning the seismic response of reinforced concrete flat slab frames. After a summary of tests on connections, the paper examines tests carried out on frames with gravity and cyclic lateral loading, and shake table tests; scaled specimens and one real scale study are included. A discussion of the results reached so far is provided focusing on the global response, the different load types and effects; the ultimate rotations at failure in relation to the gravity shear and a classification of different failure modes for different types of connections. Based on this analysis, the research needs are highlighted. An experimental program launched to address these open questions is described. Further open topics are highlighted.

Marques, Sofia Santos; Artur Silva; Manuel A. M. S. M. B. "Sustainable Amidation Reactions – Recent Advances." Eur J. Org. Chem. (2020). Abstract

Herein, we present a selection of sustainable amidation processes, that have contributed to solving the problems associated with traditional methods. Novel reagents and methods are described, including boron‐based reagents, the use of metallic and organometallic catalysts as well as metal‐free methods using milder and versatile oxidants.

Cismaşiu, C., F. P. A. Santos, R. A. D. S. Perdigão, V. M. S. Bernardo, P. X. Candeias, A. R. Carvalho, and L. M. C. Guerreiro. "Seismic Vulnerability Assessment of a RC Pedestrian Crossing." Journal of Earthquake Engineering. 24 (2020): 727-744. AbstractWebsite
n/a
Centeno, P., M. F. Alexandre, M. Chapa, JV Pinto, J. Deuermeier, T. Mateus, E. Fortunato, R. Martins, H. Águas, and MJ Mendes. "Self-Cleaned Photonic-Enhanced Solar Cells with Nanostructured Parylene-C." Advanced Materials Interfaces. 7 (2020). AbstractWebsite
n/a
Franco, N., C. Chastre, and H. Biscaia. "Strengthening RC Beams Using Stainless Steel Continuous Reinforcement Embedded at Ends." Journal of Structural Engineering (United States). 146 (2020). AbstractWebsite

An innovative system for the flexural strengthening of RC structures designated continuous reinforcement embedded at ends (CREatE) is presented in this research work. The main characteristics and procedures for the application of this new strengthening technique were described. To evaluate the performance and efficiency of this technique, a set of RC T-beams was subjected to a four-point bending test setup. The reference RC T-beam was not strengthened; all other RC T-beams were strengthened with postinstalled stainless steel bars. Different application arrangements and different amounts of reinforcement were considered, and the CREatE technique was tested under monotonic and cyclic loading histories. The tests were modeled using the nonlinear finite-element method (FEM) to predict the performance of the RC T-beams, which allowed analyzing, in detail and with good agreement with the experiments, the influence of the CREatE technique on the (1) strains developed in the concrete, (2) cracking patterns, and (3) strains developed in the stirrups. Apart from the expected increases in the flexural stiffness and load-bearing capacity of the T-beams, the results showed that the use of the CREatE technique led to higher ductility indexes in the displacement compared with traditional techniques. Moreover, with the CREatE technique, premature debonding of the reinforcement material from the concrete tensioned surface - commonly observed in externally bonded reinforcement (EBR) strengthening systems - was eliminated. © 2020 American Society of Civil Engineers.

Outis, Mani, Vitor Rosa, César AT Laia, João Carlos Lima, Sónia Barroso, Ana Luísa Carvalho, Maria José Calhorda, and Teresa Avilés. "Synthesis, Crystal Structure, and DFT Study of Two New Dinuclear Copper(I) Complexes Bearing Ar-BIAN Ligands Functionalized with NO2 Groups." European Journal of Inorganic Chemistry. 2020 (2020): 2900-2911. AbstractWebsite

{Two new bis(aryl-imino)-acenaphthene, Ar-BIAN (Ar = 2

2019
Pacheco, João Nuno, Jorge de Brito, Carlos Chastre, and Luís Evangelista. "Scatter of constitutive models of the mechanical properties of concrete: comparison of major international codes." Journal of Advanced Concrete Technology. 17 (2019): 102-125. AbstractWebsite

An investigation on the scatter of code-type constitutive models that relate compressive strength (fc) with tensile strength (fct) and Young’s modulus (Ec) of standard concrete specimens is presented. The influence of the mix design on the accuracy of the fc vs. fct and fc vs. Ecrelationships is discussed, with emphasis on the lithological type and morphology of the coarse aggregates. The uncertainty of the constitutive models is analysed in probabilistic terms and random variables that model the uncertainty of the fc vs. fct and fc vs. Ec relationships are proposed for reliability analyses of serviceability limit states. The suitability of the models proposed is assessed through preliminary conservative estimates of their design values.

Caeiro, Frederico, L{\'ı}gia Henriques-Rodrigues, and Dora Prata Gomes. "A simple class of reduced bias kernel estimators of extreme value parameters." Computational and Mathematical Methods (2019): e1025. AbstractWebsite
n/a
Brandao Moniz, António, and Bettina-Johanna Krings. "Social conditions of human-machine interaction: decision, control, qualilification." Kolloquium at Weizenbaum Institute (2019). Berlin: Weizenbaum Institute, WZB, 2019. Abstract

Due to the ongoing technical advancements in robotics, new organizational and occupational impacts are expected in different sectors. The contribution of António Moniz and Bettina-Johanna Krings focuses on the social conditions under which technology is embedded into production processes. Thus, social distribution processes, demographic change, sustainability becomes more and more important when reflecting about "technology futures".
In particular they will ask:
How does automation change work & working conditions?
Which expectations on technology are strengthen-ing the concepts of work?
Which regulations and ethics principles must be considered (safety, autonomy, control)?
Which new competences and qualification dimen-sions will be raised for non-routine tasks in auto-mated environments?
Which new types of human-machine interaction can be developed with increased cyber-physical system application at the shopfloor?

Pacheco, João Nuno, Jorge de Brito, Carlos Chastre, and Luís Evangelista. "Statistical analysis of Portuguese ready-mixed concrete production." Construction and Building Materials. 209 (2019): 283-294. AbstractWebsite

This paper evaluates and compares the statistics of compressive strength data from three Portuguese ready-mixed concrete plants. A hierarchical model showed that different groups of concrete strength records are not statistically equivalent, even if they were produced in the same plant and using the same concrete composition. This finding is related to autocorrelation. For the same specified strength class, compositions produced less often result in higher average compressive strength and variability. The statistics of one of the plants were quite different from those of the others, even though the concrete of this plant also complied with the specifications. It was found that the average compressive strength of a mix may be quite dependent on the plant that produced it, even if the compressive strength complies with quality control specifications. Conformity with the target slump and strength class was checked following the conformity criteria of EN 206-1 for continuous production. Nonconformity with slump is more frequent than failure to comply with the strength class. A bias factor for reliability analyses was proposed.

Pauleta, S. R., M. S. P. Carepo, and I. Moura. "Source and reduction of nitrous oxide." Coordination Chemistry Reviews. 387 (2019): 436-449. AbstractWebsite
n/a
Amarante dos Santos, Filipe, Gianmario Benzoni, and Fernando Fraternali. "Seismic Performance of Superelastic Tensegrity Braces." Ingegneria Sismica - International Journal of Earthquake Engineering. vol. 3 (2019).
Ribau, A. M., L. Ferrás, M. L. Morgado, M. Rebelo, and A. Afonso. "Semi-Analytical Solutions for the Poiseuille-Couette Flow of a Generalised Phan-Thien-Tanner Fluid." Fluids . 2.3 (2019).
Wadhwa, Nishtha, Pydi Ganga Bahubalindruni, Kamal Chapagai, Joao Goes, Sujay Deb, and Pedro Barquinha. "Sixth‐order differential Sallen‐and‐Key switched capacitor LPF using a‐IGZO TFTs." Int J Circ Theor Appl..no. 47 (2019): pp. 32-42.