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The action of any group on itself by conjugation and the corresponding conjugacy relation play an important role in group theory. There have been several attempts to extend the notion of conjugacy to semigroups. In this paper, we present a new definition of conjugacy that can be applied to an arbitrary semigroup and it does not reduce to the universal relation in semigroups with a zero. We compare the new notion of conjugacy with existing definitions, characterize the conjugacy in various semigroups of transformations on a set, and count the number of conjugacy classes in these semigroups when the set is infinite.

We here present fossil Crocodylomorpha eggshells from the Upper Jurassic Lourinhã Formation of Portugal, recovered from five sites: one nest from Cambelas with 13 eggs, and three partial eggs and various fragments from, Paimogo N (I), Paimogo S (II), Casal da Rola, and Peralta. All specimens but the nest were found in association with dinosaur egg material. Our research reveals that on a micro- and ultrastructural analysis, all samples present the typical characters consistent with crocodiloid eggshell morphotype, such as the shell unit shape, the organization of the eggshell layers, and the triangular blocky extinction observed with crossed nicols. We assign the material from the Lourinhã Formation to the oofamily Krokolithidae, making it the oldest crocodylomorph eggs known so far, as well as the best record for eggs of non- crocodylian crocodylomorphs. Furthermore, our study indicates that the basic structure of crocodiloid eggshells has remained stable since at least the Upper Jurassic.

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.

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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.

— Human-Computer Interaction (HCI) faces a great challenges in what concerns the creation of a fully natural interface that is able to recognize a wide range of hand gestures in real-time. Lately efforts have been made by the research community catalyzed by the wide appearance of depth sensors such as the one from the Microsoft Kinect sensor. Nevertheless the available solutions struggle to robustly recognize hand gestures since, compared with the rest of the body, the hand is a small region with many joints, difficult to recognize and ultimately track. This paper proposes a hand shape recognition method that takes advantage of the depth sensor and the joint tracking ability of Microsoft Kinect sensor. The proposed method relies on the analysis of the hand contour or outline and compares it with previously stored templates achieving a good recognition ratio and proving it eligible
for real-time scenarios.

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Spreadsheets are widely used not only to define mathematical expressions, but also to store large and complex data. To query such data is usually a difficult task to perform, usually for end user. In this work we embed the textual query language in the model-driven spreadsheet environment as a spreadsheet itself. The result is an expressive and powerful query environment that has knowledge of the business logic defined by the spreadsheet data (the spreadsheet model) to guide end users constructing correct queries.

This paper proposes and validates a model-driven software engineering technique for spreadsheets. The technique that we envision builds on the embedding of spreadsheet models under a widely used spreadsheet system. This means that we enable the creation and evolution of spreadsheet models under a spreadsheet system. More precisely, we embed ClassSheets, a visual language with a syntax similar to the one offered by common spreadsheets, that was created with the aim of specifying spreadsheets. Our embedding allows models and their conforming instances to be developed under the same environment. In practice, this convenient environment enhances evolution steps at the model level while the corresponding instance is automatically co-evolved. Finally, we have designed and conducted an empirical study with human users in order to assess our technique in production environments. The results of this study are promising and suggest that productivity gains are realizable under our model-driven spreadsheet development setting.

This paper proposes and validates a model-driven software engineering technique for spreadsheets. The technique that we envision builds on the embedding of spreadsheet models under a widely used spreadsheet system, so that models and their conforming instances are developed under the same environment. In practice, this convenient environment enhances evolution steps at the model level while the corresponding instance is automatically co-evolved. Finally, we have designed and conducted an empirical study with human users in order to assess our technique in production environments. The results of this study are promising and suggest that productivity gains are realizable under our model-driven spreadsheet development setting.

This paper presents ES-SQL, an embedded tool for visually constructing queries over spreadsheets. This tool provides an expressive query environment which has knowledge on the business logic of spreadsheets, and by this knowledge it assists the user in defining the intended queries.