4,331 research outputs found
Monofilament composites with carbon nanotubes for textile sensor applications
The aim of this work was to develop polymer matrix/carbon nanotube composite monofilaments to incorporate in textile products, to be used as sensors. The carbon nanotube polymer composite (CPC) monofilaments were produced with the required electrical and mechanical properties for the development of a textile sensor of water vapor. The monofilaments selected were formed by polylactic acid (PLA), and were incorporated directly into the fabrics. The presence of water induced a variation on the electrical conductivity of the filaments.
A textile prototype, incorporating sensors and connectors, was produced with the CPC monofilaments developed.Fundação para a Ciência e Tecnologia (FCT) - Inteltex Project, FP
Hybrid fuzzy Monte Carlo and logic programming model for distribution network reconfiguration in the presence of outages
This paper presents a methodology for distribution networks reconfiguration in outage presence in order to choose the reconfiguration that presents the lower power losses. The methodology is based on statistical failure and repair data of the distribution power system components and uses fuzzy-probabilistic modelling for system component outage parameters. Fuzzy membership functions of system component outage parameters are obtained by statistical records. A hybrid method of fuzzy set and Monte Carlo simulation based on the fuzzy-probabilistic models allows catching both randomness and fuzziness of component outage parameters.
Once obtained the system states by Monte Carlo simulation, a logical programming algorithm is applied to get all possible reconfigurations for every system state.
In order to evaluate the line flows and bus voltages and to identify if there is any overloading, and/or voltage violation a distribution power flow has been applied to select the feasible reconfiguration with lower power losses.
To illustrate the application of the proposed methodology to a practical case, the paper includes a case study that considers a real distribution network
Segurança sísmica de escolas do plano dos centenários existentes no Algarve: caso de estudo
As escolas do “Plano dos Centenários” correspondem à tipologia de escolas do primeiro ciclo do ensino básico existente no Algarve com o maior número de edifícios ainda em funcionamento. Por outro lado, mesmo já não estando a desempenhar as iniciais funções, muitas dessas antigas “Escolas Primárias” são hoje utilizadas para outras funções, designadamente como escolas pré-primárias ou como associações culturais ou recreativas, por exemplo. É inegável o valor patrimonial destas construções, quer pelas suas distintas características arquitetónicas, quer pelo seu valor histórico. Estes edifícios foram construídos com paredes resistentes em alvenaria de pedra da região, antes da publicação em Portugal dos primeiros códigos sísmicos. Assim, é da maior importância o estudo da segurança sísmica destas construções, atendendo à elevada concentração de pessoas que apresentam, sendo a maior parte delas crianças. Estas construções têm sido alvo de obras de reabilitação, mas meramente procurando melhorar a sua habitabilidade, sem qualquer preocupação com a segurança sísmica. É neste contexto que surge o projeto PERSISTAH, que visa, entre outros objetivos, estudar o risco sísmico das escolas do primeiro ciclo que estão em funcionamento nas regiões do Algarve (Portugal) e de Huelva (Espanha).
Neste trabalho, é apresentado o estudo de um edifício do “Plano dos Centenários” localizado em Olhão. Em primeiro lugar, foram realizadas análises não lineares do edifício, tendo sido obtidas as correspondentes curvas de capacidade do edifício com o recurso ao programa Tremuri. Depois, as múltiplas curvas de capacidade foram importadas para o programa EC8spec. Este programa permite determinar os pontos de desempenho (deslocamentos alvo) das estruturas através do método N2, e para as ações estabelecidas na NP EN 1998-1:2010, assim como possibilita a determinação das percentagens dessa ação a que correspondem os pontos de desempenho associados aos três estados limites estipulados na NP EN 1998-3:2017: colapso eminente (NC), danos severos (SD) e limitação de dano (DL). De acordo com a NP EN 1998-3:2017, e porque as escolas correspondem a estruturas de classe de importância III, a avaliação da segurança tem de ser realizada para todos estes estados limites.
Os resultados obtidos neste estudo revelam que não é possível atingir os níveis de segurança que estão estipulados na NP EN 1998-3:2017 para o Algarve, para todos os estados limites atrás referidos, sendo por isso desejável a realização de um adequado reforço sísmico.info:eu-repo/semantics/publishedVersio
Developing a data fusion concept for radar and optical ground based SST station
As part of the Portuguese Space Surveillance and Tracking (SST) program, a
tracking radar and a double Wide Field of View Telescope system (4.3{\deg} x
2.3{\deg}) are being installed at the Pampilhosa da Serra Space Observatory
(PASO) in the centre of continental Portugal, complementing an already
installed deployable optical sensor for MEO and GEO surveillance. The tracking
radar will track space debris in Low Earth Orbit (LEO) up to 1000 km and at the
same time the telescope will also have LEO tracking capabilities. This article
intends to discuss possible ways to take advantage of having these two sensors
at the same location. Using both types of sensors takes advantage of the radar
measurements which give precise radial velocity and distance to the objects,
while the telescope gives better sky coordinates measurements. With the
installation of radar and optical sensors, PASO can extend observation time of
space debris and correlate information from optical and radar provenances in
real time. During twilight periods both sensors can be used simultaneously to
rapidly compute new TLEs for LEO objects, eliminating the time delays involved
in data exchange between sites in a large SST network. This concept will not
replace the need for a SST network with sensors in multiple locations around
the globe, but will provide a more complete set of measurements from a given
object passage, and therefore increase the added value for initial orbit
determination, or monitoring of reentry campaigns of a given location. PASO
will contribute to the development of new solutions to better characterize the
objects improving the overall SST capabilities and constitute a perfect site
for the development and testing of new radar and optical data fusion algorithms
and techniques for space debris monitoring.Comment: 3 pages, 3 figures, Draft accepted for publication at 73rd
International Astronautical Congress, Paris 202
Radio astronomy and Space science in Azores: enhancing the Atlantic VLBI infrastructure cluster
Radio astronomy and Space Infrastructures in the Azores have a great
scientific and industrial interest because they benefit from a unique
geographical location in the middle of the North Atlantic allowing a vast
improvement in the sky coverage. This fact obviously has a very high added
value for: i) the establishment of space tracking and communications networks
for the emergent global small satellite fleets ii) it is invaluable to connect
the radio astronomy infrastructure networks in Africa, Europe and America
continents using Very Large Baseline Interferometry (VLBI) techniques, iii) it
allows excellent potential for monitoring space debris and Near Earth Objects
(NEOs). There is in S. Miguel island a 32-metre SATCOM antenna that could be
integrated in advanced VLBI networks and be capable of additional Deep Space
Network ground support. This paper explores the space science opportunities
offered by the upgrade of the S. Miguel 32-metre SATCOM antenna into a
world-class infrastructure for radio astronomy and space exploration: it would
enable a Deep Space Network mode and would constitute a key space facility for
data production, promoting local digital infrastructure investments and the
testing of cutting-edge information technologies. Its Atlantic location also
enables improvements in angular resolution, provides many baseline in East-West
and North-South directions connecting the emergent VLBI stations in America to
Europe and Africa VLBI arrays therefore contributing for greater array imaging
capabilities especially for sources or well studied fields close to or below
the celestial equator, where ESO facilities, ALMA, SKA and its precursors do or
will operate and observe in the coming decades.Comment: 14 pages, 7 figures, 3 tables. Accepted for Publication at Advances
in Space Research, COSPAR, Elsevie
Early experience with targeted therapy and dendritic cell vaccine in metastatic renal cell carcinoma after nephrectomy
PURPOSE: Metastatic renal cell carcinoma (RCC) is one of the most treatment-resistant malignancies and nephrectomy, isolated or combined with systemic chemotherapy typically has limited or no effectiveness. We report our initial results in patients treated with the association of molecular targeted therapy, nephrectomy, and hybrid dendritic-tumor cell (DC) vaccine. MATERIALS AND METHODS: Two male patients diagnosed with metastatic RCC were selected for the study. They were treated with the triple strategy, in which sunitinib (50 mg per day) was given for 4 weeks, followed by radical nephrectomy after two weeks. DC vaccine was initiated immediately after surgery and repeated monthly. Sunitinib was restarted daily after 2 to 3 weeks of surgery with a 7-day interval every 4 weeks. RESULTS: Both patients had complete adherence to the proposed treatment with DC vaccine therapy combined with sunitinib. Follow-up in these patients at 9 and 10 months demonstrated a stable disease in both, as shown by imaging and clinical findings, with no further treatment required. CONCLUSION: The immune response obtained with DC vaccine combined with the antiangiogenic effect of sunitinib and the potential benefits of cytoreductive nephrectomy in advanced disease could represent a new option in the treatment of metastatic RCC. Further prospective trials are needed not only to elucidate the ideal dosing and schedule, but also to better define the proof-of-concept proposed in this report and its role in clinical practice
Seedless Cu electroplating on Co-W thin films in low pH electrolyte: early stages of formation
The use of Ta/TaN barrier bilayer systems in electronic applications has been ubiquitous over the last decade. Alternative materials such as Co-W or Ru-W alloys have gathered interest as possible replacements due to their conjugation of favourable electrical properties and barrier layer efficiency at reduced thicknesses while enabling seedless Cu electroplating. The microstructure, morphology, and electrical properties of Cu films directly electrodeposited onto Co-W or Ru-W are important to assess, concomitant with their ability to withstand the electroplating baths/conditions. This work investigates the effects of the current application method and pH value of the electroplating solution on the electrocrystallisation behaviour of Cu deposited onto a Co-W barrier layer. The film structure, morphology, and chemical composition were studied by X-ray diffraction, scanning electron microscopy and atomic force microscopy, as well as photoelectron spectroscopy. The results show that the electrolyte solution at pH 1.8 is incapable of creating a compact Cu film over the Co-W layer in either pulsed or direct-current modes. At higher pH, a continuous film is formed. A mechanism is proposed for the nucleation and growth of Cu on Co-W, where a balance between Cu nucleation, growth, and preferential Co dissolution dictates the substrate area coverage and compactness of the electrodeposited films.Portugal 2020 through European Regional Development Fund (FEDER) in the frame of Operational Competitiveness and Internationalisation Programme (POCI) and in the scope of the project USECoIN with grant number PTDC/CTM-CTM/31953/2017. This work was also supported by FCT, through IDMEC, under LAETA project UIDB/50022/202
Self-Determined Motivation and Competitive Anxiety in Athletes/Students: A Probabilistic Study Using Bayesian Networks
This study attempts to analyze the relationship between two key psychological variables associated with performance in sports – Self-Determined Motivation and Competitive Anxiety – through Bayesian Networks (BN) analysis. We analyzed 674 university students that are athletes from 44 universities that competed at the University Games in Mexico, with an average age of 21 years (SD = 2.07) and with a mean of 8.61 years’ (SD = 5.15) experience in sports. Methods: Regarding the data analysis, firstly, classification using the CHAID algorithm was carried out to determine the dependence links between variables; Secondly, a BN was developed to reduce the uncertainty in the relationships between the two key psychological variables. The validation of the BN revealed AUC values ranging from 0.5 to 0.92. Subsequently, various instantiations were performed with hypothetical values applied to the “bottom” variables. Results showed two probability trees that have extrinsic motivation and amotivation at the top, while the anxiety/activation due to worries about performance was at the bottom of the probabilities. The instantiations carried out support the existence of these probabilistic relationships, demonstrating their scarce influence on anxiety about competition generated by the intrinsic motivation, and the complex probabilistic effect of introjected and identified regulation regarding the appearance of anxiety due to worry about performance
Investigating LGALS3BP/90 K glycoprotein in the cerebrospinal fluid of patients with neurological diseases
© The Author(s) 2020. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Galectin-3 binding protein (LGALS3BP or 90 K) is a secreted glycoprotein found in human body fluids. Deregulated levels were observed in cancer and infection and its study in neurological diseases is more recent. Here, we have investigated 90 K from human cerebrospinal fluid (CSF) of patients with amyotrophic lateral sclerosis (ALS, n = 35) and other neurological diseases (n = 23). CSF was fractionated by ultrafiltration/size-exclusion chromatography (SEC) and eluted fractions were analysed by complementary techniques including immunoblotting, electron microscopy and nano-liquid chromatography-tandem mass spectrometry. A fraction of 90 K appeared as nanoparticles of irregular shape with heterogeneous dimensions of 15-60 nm that co-eluted with extracellular vesicles in SEC. Median levels of 90 K quantified by ELISA were not different between ALS patients (215.8 ng/ml) and controls (213.3 ng/ml) in contrast with the benchmark biomarker for ALS phosphoneurofilament heavy chain (1750 and 345 pg/ml, respectively). A multiregression model supported age is the only independent predictor of 90 K level in both groups (p < 0.05). Significant correlation was found between 90 K levels and age for the ALS group (r = 0.366, p = 0.031) and for all subjects (r = 0.392, p = 0.003). In conclusion, this study unveils the presence of 90 K-containing nanoparticles in human CSF and opens novel perspectives to further investigate 90 K as potential aging marker.This work was supported by Euronanomed 2 ERA-NET project GlioEx (ENMed/0001/2013), Fundação para a Ciência e a Tecnologia (FCT), Portugal; iNOVA4Health Research Unit (LISBOA-01–0145-FEDER-007344), which is cofunded by FCT/Ministério da Ciência e do Ensino Superior, through national funds; and by FEDER under the PT2020 Partnership Agreement.info:eu-repo/semantics/publishedVersio
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