Browsing by Author "Pereira, A."
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- Evaluación del crecimiento de ostras en el estuario del Sado (Portugal) y su relación con las condiciones ambientalesPublication . Galhanas, D.; Vieira, C.; Pereira, A.; Mata, A. M. T.; Salgado, R.
- Long term experience in Autonomous Stations and production quality controlPublication . Lopes, L.; Alves, A.B.; Assis, P.; Blanco, A.; Carolino, N.; Cerda, M.A.; Conceição, R.; Cunha, O.; Dobrigkeit, C.; Ferreira, M.; Fonte, P.; de Almeida, L.; Luz, R.; Martins, V.B.; Mendes, L.; Nogueira, J.C.; Pereira, A.; Pimenta, M.; Sarmento, R.; de Souza, V.; Tomé, B.
- MARTA: a high-energy cosmic-ray detector concept for high-accuracy muon measurementPublication . Abreu, P. et al. (45 authors); Andringa, S.; Assis, P.; Blanco, A.; Brogueira, P; Carolino, N.; Cazon, L.; Conceição, R.; Cunha, O; Diogo, F.; Espadanal, J.; Ferreira, M.; Ferreira, P.; Fonte, P.; Gonçalves, P.; Lopes, L.; Mendes, L.; Pereira, A.; Pimenta, M.; Sarmento, R.; Tomé, B.; Wolters, H.A new concept for the direct measurement of muons in air showers is presented. The concept is based on resistive plate chambers (RPCs), which can directly measure muons with very good space and time resolution. The muon detector is shielded by placing it under another detector able to absorb and measure the electromagnetic component of the showers such as a water-Cherenkov detector, commonly used in air shower arrays. The combination of the two detectors in a single, compact detector unit provides a unique measurement that opens rich possibilities in the study of air showers.
- Mechanical construction and installation of the ATLAS tile calorimeterPublication . ATLAS Tile Calorimeter collaboration (234 authors); Alves, R.; Amaral, P.; Carvalho, J.; David, M.; Gomes, A.; Maio, A.; Marques, C.; Onofre, A.; Pereira, A.; Pina, J.; Pinhão, J.; Santos, J.; Saraiva, J.G.; Silva, J.This paper summarises the mechanical construction andinstallation of the Tile Calorimeter for the ATLASexperiment at the Large Hadron Collider in CERN, Switzerland. The TileCalorimeter is a sampling calorimeter using scintillator as the sensitivedetector and steel as the absorber and covers the central region of the ATLASexperiment up to pseudorapidities ±1.7. The mechanical construction ofthe Tile Calorimeter occurred over a periodof about 10 years beginning in 1995 with the completionof the Technical Design Report and ending in 2006 with the installationof the final module in the ATLAS cavern. Duringthis period approximately 2600 metric tons of steel were transformedinto a laminated structure to form the absorber of the sampling calorimeter.Following instrumentation and testing, which is described elsewhere, themodules were installed in the ATLAS cavern with a remarkable accuracy fora structure of this size and weight.
- Muon Array with RPCs for Tagging Air showers (MARTA)Publication . Sarmento, Raul et al. (42 authors); Abreu, Pedro; Andringa Dias, Sofia; Assis, Pedro; Castro, Alberto Blanco; Brogueira, Pedro; Carolino, N.; Cazon, Lorenzo; Cunha, Orlando; Diogo, Francisco; Espadanal, João; Ferreira, Miguel; Fonte, Paulo; Goncalves, Patricia; Lopes, Luis; Luz, Ricardo; Mendes, Luis; Pereira, A.; Pimenta, M.; Espirito Santo, Catarina; Tome, B.; Wolters, HelmutWe discuss the concept of an array with Resistive Plate Chambers (RPC) for muon detection in ultra-high energy cosmic ray (UHECR) experiments. RPC have been used in particle physics experiments due to their fast timing properties and spatial resolution. The operation of a ground array detector poses challenging demands, as the RPC must operate remotely under extreme en- vironments, with limited power and minimal maintenance. In its baseline configuration, each MARTA unit includes one 1.5x1.2 m 2 RPC, with 64 pickup electrodes (pads). The DAQ sys- tem is based on an ASIC, allowing one to read out the high number of channels with low power consumption. Data are recorded using a dual technique: single particle counting with a simple threshold on the signal from each pad and charge integration for high occupancy. The RPC, DAQ, High Voltage and monitoring systems are enclosed in an aluminum-sealed case, providing a com- pact and robust unit suited for outdoor environments, which can be easily deployed and connected. The RPCs developed at LIP-Coimbra are able to operate using very low gas flux, which allows running them for few years with a small gas reservoir. Several full-scale units are already installed and taking data in several locations and with different configurations, proving the viability of the MARTA concept. By shielding the detector units with enough slant mass to absorb the electro- magnetic component in the air showers, a clean measurement of the muon content is allowed, a concept to be implemented in a next generation of UHECR experiments. The specificities of a MARTA unit are presented, which include particle counting with high efficiency, time resolu- tion and spatial segmentation. The potential of the MARTA concept for muon measurements in air showers is assessed, as well as tentative methods for calibration and cross-calibrations with existing detectors.
- Outdoor Field Experience with Autonomous RPC Based StationsPublication . Lopes, L.; Assis, P.; Blanco, A.; Carolino, N.; Cerda, M.A.; Conceição, R.; Cunha, O.; Ferreira, M.; Fonte, P.; Luz, R.; Mendes, L.; Pereira, A.; Pimenta, M.; Sarmento, R.; Tomé, B.In the last two decades Resistive Plate Chambers were employed in the Cosmic Ray Experiments COVER-PLASTEX and ARGO/YBJ. In both experiments the detectors were housed indoors, likely owing to gas distribution requirements and the need to control environment variables that directly affect RPCs operational stability. But in experiments where Extended Air Shower (EAS) sampling is necessary, large area arrays composed by dispersed stations are deployed, rendering this kind of approach impossible. In this situation, it would be mandatory to have detectors that could be deployed in small standalone stations, with very rare opportunities for maintenance, and with good resilience to environmental conditions. Aiming to meet these requirements, we started some years ago the development of RPCs for Autonomous Stations. The results from indoor tests and measurements were very promising, both concerning performance and stability under very low gas flow rate, which is the main requirement for Autonomous Stations. In this work we update the indoor results and show the first ones concerning outdoor stable operation. In particular, a dynamic adjustment of the high voltage is applied to keep gas gain constant.
- (Re) Examining the Factorial Structure of the Generalized Anxiety Disorder-7 in a College Students SamplePublication . Monteiro, S.; Bártolo, A.; Torres, A.; Pereira, A.Introduction Generalized anxiety in young adults during college career is a serious public-health problem that untreated has a chronic course. Research has shown that the self-report questionnaire generalized anxiety disorder-7 (GAD-7) is a reliable and valid measure to assess generalized anxiety symptoms severity in heterogeneous psychiatric samples. However, GAD-7 is not available for non-clinical populations and their factor structure has not been re-examined.
- Reclassification of the intermediate group classified according to heartscore taking in considertaion individual genetic predisposition to coronary artery diseasePublication . Mendonça, M.; Pereira, A.; Rodrigues, R.; Neto, M.; Sousa, A.C.; Freitas, S.; Freitas, C.; Freitas, A.I.; Borges, S.; Palma dos Reis, R.Introduction: Cardiovascular risk stratification has included traditional cardiovascular risk factors (TRF) including tobacco, cholesterol and blood pressure adjusted to age and sex. The utility of genetic risk scores (GRS) as predictors of cardiovascular risk remains inconclusive. Objective: We intended to evaluate the ability of a multilocus GRS within the intermediate risk subgroup, defined by the European Heart score, to add predictive power for the association with coronary artery arterial disease (CAD). Methods: After applying European SCORE (ES) stratification to a total population of 2703 Portuguese individuals, 639 individuals with 59.0 ± 4.3 years were considered to be at intermediate risk subgroup (2 Results: GRS was an independent predictor for CAD (OR=2.411; p<0.0001). Diabetes mellitus (OR=3.196;p<0.0001), arterial hypertension (OR=2.201; p=0.003) and smoking (OR=3.148; p<0.0001) were also significantly associated with CAD. AUC increased from 0.694 to 0.734 after adding GRS to TRF. When discriminated by tertiles of GRS, the AUC for TRF was maximum for the 2nd tertile GRS [AUC (TRF)=0.734] and lower for the 1st and 3rd tertiles (AUC =0.673 and AUC =0.671, respectively). NRI showed better increase in the intermediate risk subgroup with a 35.2% interpreted as the roportion of patients reclassified to a more appropriate risk category, and 29.4% on the lower risk. Conclusion: In our population, the GRS increased the predictive value of TRF in the subgroup of patients at intermediate risk by the European Score. The predictive value of TRF is lower in patients with higher GRS. In this subgroup, the inclusion of genotyping may be considered for better stratification of cardiovascular risk.
- The Egas Moniz histology digital platform : a dream that came truePublication . Cavacas, M. A.; Pereira, A.; Oliveira, V. Braz de; Remédios, M.; Cavacas, A. R.; Gancho, R.; Pimenta, F.; Botelho, J.; Henriques, P.; Borrecho, G.; Oliveira, P.; Camisão, J.; Marques, M. E.; Mendes, José João
- Using educational networks to promote internalization experiences in physiotherapy educationPublication . Lopes, A. Alves; Prado, A.; Pereira, A.; Leão, C.; Martins, E.; Valente, F.; Rocha, F. Mazzoli; Pacheco, G.; Sousa, J. Luís; Pedro, M.; Gagulic, S.