Neste texto apresentamos os jogos no ensino da matemática como uma forma de aprendizagem de conteúdos e não apenas como um recurso que cada professor pode usar nas suas aulas para tornar a aula diferente. Analisamos dois jogos desenvolvidos por nós e que utilizámos com alunos dos 7.º e 10.º anos de escolaridade, procurando não só apresentar os jogos, mas também aspetos da sua implementação em sala de aula, ponderando o contributo que trouxeram à aprendizagem dos alunos.
Aprender matemática depende de um grande número de variáveis, o que torna o ensino um processo complexo, pois é necessário que se desenvolva o raciocínio lógico, além de estimular o desenvolvimento das mais variadas capacidades transversais, tais como o pensamento autónomo, a criatividade, o sentido de estratégia e a capacidade de resolver problemas.
Duas das dificuldades frequentemente encontradas pelos professores passam pela falta de motivação para a aprendizagem e pelo desinteresse pela Matemática. A solução para estes problemas pode passar pela utilização de jogos para complementar o estudo, mas também para a aquisição de novos conteúdos. No entanto, apenas a implementação dos jogos não basta. O papel do professor é de extrema importância e a planificação e orientação da aula são fundamentais para que se alcancem os objetivos pretendidos.

Multi-threaded programs allow one to achieve better performance by doing a lot of work in parallel using multiple threads. Such parallel programs often contain code blocks that a thread must execute atomically, i.e., with no interference from the other threads of the program. Failing to execute these code blocks atomically leads to errors known as atomicity violations. However, frequently it not obvious to tell when a piece of code should be executed atomically, especially when that piece of code contains calls to some third-party library functions, about which the programmer has little or no knowledge at all. One solution to this problem is to associate a contract with such a library, telling the programmer how the library functions should be used, and then check whether the contract is indeed respected. For contract validation, static approaches have been proposed, with known limitations on precision and scalability. In this paper, we propose a dynamic method for contract validation, which is more precise and scalable than static approaches.

This paper presents a low-offset comparator based on n-type amorphous indium gallium zinc oxide thin-film transistors (TFTs). An a-Si:H TFT model was adapted to fit the electrical characterization data obtained for these devices. The proposed comparator comprises three pre-amplification stages, a positive-feedback analog latch and a fully dynamic digital latch. Simulation results show that the proposed circuit can work at several tens of kHz, with an accuracy of the order of 10 mV, considering a supply voltage of 10 V and a current consumption of 380 μA. Monte-Carlo simulations exhibit a 1-sigma random offset voltage smaller than 10 mV and 40 mV, respectively, with and without using autozeroing techniques. © 2015 IEEE.

The direct identification of the cohesive law in pure mode I of Pinus pinaster is addressed. The approach couples the double cantilever beam (DCB) test with digital image correlation (DIC). Wooden beam specimens loaded in the radial-longitudinal (RL) fracture propagation system are used. The strain energy release rate in mode I (GI ) is uniquely determined from the load-displacement ( P ?? ) curve by means of the compliance-based beam method (CBBM). This method relies on the concept of equivalent elastic crack length ( eq a ) and therefore does not require the monitoring of crack propagation during test. The crack tip opening displacement in mode I ? ? I w is determined from the displacement field at the initial crack tip. The cohesive law in mode I I I (? ? w ) is then identified by numerical differentiation of the I I G ? w relationship. Moreover, the proposed procedure is validated by finite element analyses including cohesive zone modelling. It is concluded that the proposed data reduction scheme is adequate for assessing the cohesive law in pure mode I of P. pinaster.

The influence of Ag nanoparticles (Ag NPs) on the luminescence of electrospun nonwoven mats made of polyvinylpyrrolidone (PVP) has been studied in this work. The PVP fibers incorporating 2.1-4.3 nm size Ag NPs show a significant photoluminescence (PL) band between 580 and 640 nm under 325 nm laser excitation. The down conversion luminescence emission is present even after several hours of laser excitation, which denotes the durability and stability of fibers to consecutive excitations. As so these one-dimensional photonic fibers made using cheap methods is of great importance for organic optoelectronic applications, fluorescent clothing or counterfeiting labels. © 2014 Elsevier B.V. All rights reserved.

This paper presents a domain-specific querying language for model-driven spreadsheets. We briefly show the design of the language and present in detail its implementation, from the denormalization of data and translation of our user-friendly query language to a more efficient query, to the execution of the query using Google. To validate our work, we executed an empirical study, comparing QuerySheet with an alternative spreadsheet querying tool, which produced positive results.

N2OR has been found to have two structural forms of its tetranuclear copper active site, the 4CuS Cu(Z)* form and the 4Cu2S Cu(Z) form. EPR, resonance Raman, and MCD spectroscopies have been used to determine the redox states of these sites under different reductant conditions, showing that the Cu(Z)* site accesses the 1-hole and fully reduced redox states, while the Cu(Z) site accesses the 2-hole and 1-hole redox states. Single-turnover reactions of N2OR for Cu(Z) and Cu(Z)* poised in these redox states and steady-state turnover assays with different proportions of Cu(Z) and Cu(Z)* show that only fully reduced Cu(Z)* is catalytically competent in rapid turnover with N2O.

Abstract
Late Jurassic dinosaur footprints were found on a coastline cliff in Lourinhã, Porto das Barcas, Lagido do Forno (coordinate 39°14.178’N, 9°20.397’W, Portugal) in June 2001. The locality is characterized by steep cliffs with high slopes that are composed of gray and red sandstones/ siltstones. The location belongs to the successions of Lusitanian Basin representing the Porto Novo Member of the Lourinhã Formation. Three natural infills of tridactyl tracks, possibly ascribed to ornithopod, a bipedal herbivore were found, representing a left foot movement, a right and a left one, respectively. Footprints are 300- 400mm wide and have a height of 330-360mm. The footprints are characterized by round fingers, which are elongated due to some degradation/ erosion. The footprints were collected from the field in 2001 and subsequently cleaned, consolidated and glued in the laboratory of the Museum of Lourinhã before being exhibited in a museum display. Stone matrix was removed and a consolidation product was applied, probably a polyvinyl acetate. The footprint with broken central digit was glued with an epoxy resin, Araldite. Both applied products were confirmed by analysis of μ- FTIR and both presented colour change and detachment surface problems. The footprints have been exposed in the palaeontology hall of the Museum of Lourinhã, Portugal from 2004 without climate controlling. These trace fossils form an important part of the palaeontological collection of Late Jurassic vertebrate fossils from Lourinhã Formation. Presently, it is considered a unique heritage in danger of disappearing due to high decay level of disaggregation of its geological structure. The footprints display several pathologies, such as “Blistering”, “Powdering”, “Exfoliation”’ as well as “Dirt”, “Fracture”’, “Inscriptions”, “Consolidants” and “Adhesives” and are now in very poor conditions. Laboratorial analysed were made to evaluate the presence of salts. Moreover a microclimatic study was conducted inside the museum to evaluate the influence of thermo-hygrometric parameters on the decay processes. The future interventions will depend on the results of consolidation trials that are currently under progress by using stone samples taken from the same layer and location from Porto das Barcas applying different commercial consolidation products.

This paper proposes a systematic methodology for supply chain planning optimization and assessment of different scenarios. This methodology will help companies throughout the difficult process of strategic decision-making in what concerns the design of an efficient supply chain structure. The proposed methodology allows the analysis of complex systems as it integrates a decision support tool developed to agile the process of scenario comparison, when designing network structures. This tool allows practitioners to take advantage of the optimization models without the need of learning modelling languages. An example based on a real case study is presented, showing the methodology/tool applicability.

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This study looks at the analysis of the interface between Fiber Reinforced Polymer (FRP)-to-parent material bonded interfaces. The performance of FRP-to-parent material bonded joints for the Externally Bonded Reinforcement (EBR) technique is numerically modelled with the PFC2D software which is based on the Distinct Element Method (DEM). It is believed that this represents the first time the DEM has been used to simulate the delamination process of FRP-to-parent material bonded joints. In order to validate the analysis performed with the DEM, a Pull-out test with no slip constrains was modelled and different linear bond-slip laws were assumed. The numerical results revealed that the DEM is capable of estimating with good accuracy the exact solutions of bond stresses, strains or slippages along the bonded length for linear bond-slip laws. The bi-linear law available in PFC2D was then compared to the numerical results obtained from other another code developed by the author. The delamination process of Pull-out tests with slip constrain at one of the free ends of the FRP plate is also described and analyzed. The results obtained from the DEM revealed that the delamination process ends with stiffness equal to the axial stiffness of the FRP plate. This evidence highlights the need to design mechanical anchor devices capable of preventing premature debonding which is known to occur on EBR systems.

The human macrophage galactose-type lectin (hMGL) is a key physiological receptor for the carcinoma-associated Tn antigen (GalNAc-α-1-O-Ser/Thr) in mucins. We herein report NMR- and modeling-based data on the molecular recognition features of synthetic Tn-bearing glycopeptides by hMGL. Cognate epitopes on the sugar and matching key amino acids involved in the interaction have been identified by saturation transfer difference (STD) NMR spectroscopy. Only the amino acids close to the glycosylation site in the peptides are involved in lectin contact. Moreover, control experiments with non-glycosylated MUC1 peptides unequivocally showed that the sugar residue is essential for hMGL binding, as is Ca2+. The dissociation constants (Kd) have been estimated by STD titrations and/or STD competition experiments and show that Gal was a poor binder for hMGL, with a Kd in the mM range, while GalNAc and MUC1 Tn-glycopetides reached Kd values in the lower μM range. STD-based results suggested a distinct interacting epitope for the two monosaccharides. NMR data have been complemented with molecular dynamics simulations and Corcema- ST to establish a 3D view on the molecular recognition process between Gal, GalNAc and the Tn-presenting glycopeptides and hMGL. Gal and GalNAc have a dual binding mode with opposite trend of the main interaction pattern and the differences in affinity can be explained by additional hydrogen bonds and CH-π contacts involving exclusively the NHAc moiety.