Shock absorbers have been widely used in the automotive and aeronautical industries for many years. Inspired on these devices, the paper presents an analytical and numerical assessment of a high performance protective system for building structures against blast loads, which is composed of a shielding element connected to the main structure, at the floor levels, through ductile Energy Absorbing Connectors (EACs). The EACs exploit the external tube inversion mechanism to absorb a significant part of the imparted kinetic energy from the blast wave. While the system prototype has been developed in laboratory, it was characterized and tested in a full-scale blast testing campaign. A validated finite element model was used next to analyze its performance in a more demanding design scenario. The introduction of EACs notably reduces the peak horizontal loads and the kinetic energy transferred to the protected structure, being expected a significant reduction of the stresses in the supporting vertical elements, in addition to the protection of structural and non-structural members. These results encourage further studies of the presented protective system that can be potentially employed for a large variety of blast threat scenarios, especially when increasing the stand-off is not a possible/viable option and sensitive facilities have to be protected.

In this paper, we characterize the monoid of endomorphisms of the semigroup of all monotone full transformations of a finite chain, as well as the monoids of endomorphisms of the semigroup of all monotone partial transformations and of the semigroup of all monotone partial permutations of a finite chain.

The challenges of disciplinary integration in teaching practice, especially in the implementation of tasks that promote interdisciplinary approaches, highlight the importance of teachers' professional knowledge in this process. Using a naturalistic approach, this study aims to characterize the professional knowledge of a physics teacher when adopting an interdisciplinary approach using technology. The results of the research revealed that the teacher mobilizes different types of knowledge, showing a differentiated knowledge of the most appropriate mathematical application to teach a given piece of content, and knowledge of how pedagogical strategies can be aided through different applications using technology.

ABSTRACTVirtual palaeontology is a growing field, leading palaeontologists to better understand the microanatomy of many extinct species. The application of techniques such as CT and μCT-scanning allows the researchers to study micro-anatomical features in a non-invasive way and make inferences on the palaeobiology of animals. Dinosaurs have been extensively studied using these techniques, with particular focus on the microanatomy of the cranium, whereas relatively little is known of other cranial elements, such as the lower jaw. Here, we aim to fill this gap, describing the microanatomy of the specimen ML 768, an isolated dentary belonging to a dryosaurid iguanodontian dinosaur from the Upper Jurassic of Lourinhã Fm. The dentary ML 768 was subjected to μCT-scanning, and subsequently the data were segmented in Avizo and rendered in Blender. We identified functional and replacement teeth, recognising remnants of old replacement cycles. Furthermore, we mapped a rich neurovascular network present in the dentary and compared it with reference literature. We found that the high vascularisation is shared with other cerapodan dinosaurs with high tooth replacement rates, although homoeostasis may have also played a role in the development of this condition. Further evidence is needed to appreciate the macroevolutionary significance of these findings.

Abstract The Monastery of Alcobaça houses in reserve the ceramic tiles that adorned the floor of the church's apse. These tiles were removed during rehabilitation works and many preserve part of their original fixing mortars. A comprehensive analysis of 21 samples was conducted using a multi-analytical approach (X-ray fluorescence, X-ray diffraction, scanning electron microscopy–energy-dispersive X-ray spectroscopy, μ-Raman spectroscopy, thermogravimetry–differential thermal analysis, optical microscopy, and colorimetry). Results suggest compositional variations in the samples from the back and sides of the ceramic tiles; however, the mineralogy and general characteristics of the aggregates remained consistent between the samples and are coherent with the local geology, suggesting a shared historical origin.

Political and economic crises and issues such as global warming, decreased fossil fuel reserves, environmental pollutions and acid rains are just some of the problems caused by improper energy consumption. Energy efficiency optimization with the right policy and definition of accurate scientific methods proven in energy consumption includes planning, enforcement, organizing permanent control, and continuously reviewing technology upgrades. Additionally, developing legal solutions to implement these programs prevents the destruction and waste of energy resources and reduces the side effects of improper energy consumption. The shape of the city and its components can affect the city’s quality and its spaces, as well as the air quality change, creating a particular climate in their area, causing phenomena such as heat islands, dust, rain, albedo, atmospheric inversion, and some others. By making changes in the shape of the city, both on a large scale and a micro-scale, atmospheric currents and, consequently, air quality in cities can be improved. Urban morphological indicators, including building height, building type, occupancy level, segmentation, block size, block shape, density, and urban green, can affect the weather and climate conditions outside and inside the building and, thus, the energy demand in the areas. By creating effective reforms in the model of configuration of the urban regions, including the pattern of land fragmentation, the physical characteristics of buildings, the network of passages and open spaces, it is possible to increase the energy efficiency of buildings in the long term in the regional(synoptic) climatic conditions of the city and the neighbourhood.

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Stegosaurs are a small but iconic clade of ornithischian dinosaurs. They and their sister taxa, the ankylosaurs, formed the clade Eurypoda which means ‘broad-footed’. Here, we describe a stegosaur from the Upper Jurassic Qigu Formation of Xinjiang, China, based on an associated partial skeleton that includes axial, pectoral girdle, pelvic girdle, limb and armor elements. It can be diagnosed as a new taxon, Angustungui, based on numerous autapomorphies. Some morphologies of Angustungui are more similar to the taxa from Europe, Africa and North America than to those from Asia. Our phylogenetic analysis recovers it as the sister taxon of Loricatosaurus. More importantly, the narrow and claw-shaped ungual of Angustungui proves that Eurypoda, at least stegosaur, has claw-shaped unguals. Besides, we revised the character scores for Chinese stegosaurs based on observations of the specimens.Competing Interest StatementThe authors have declared no competing interest.

Since Seymour Papert's work with the Logo programming language in the 1960s, there has been a prevailing belief in the effectiveness of visual programming environments for teaching programming to children and novices. As these platforms evolved and became more prevalent, using block programming to teach children and beginners became increasingly more common. However, modern block programming platforms like Scratch and Code.org excessively restrict educators by not allowing them to create custom exercises in the platform. They also tend to make programming a solo activity, not allowing for collaboration and cooperation between learners (Scratch is an exception in this regard). Additionally, they are usually located in standalone websites instead of being implemented in locations that students already frequent regularly. Having identified these gaps in the field of block programming environments, this paper proposes NextBlocks, a new block programming platform implemented as a Moodle plugin. This platform enables educators to create custom exercises, emphasizing social perception and collaboration features. It supports features that are uncommon in block programming environments, contributing to a more interactive and engaging learning experience. Furthermore, being integrated into the Moodle Learning Management System makes NextBlocks more easily accessible within the educational framework. As an open-source platform, besides solving current challenges, it can also serve as a foundation for future expansion by the education community. This paper explores some of the unique features of NextBlocks, presents a case study on the platform, and discusses its potential contributions to enhancing programming education for beginners within a collaborative learning environment.

Allosaurus Marsh, 1877 is one of the most iconic theropods of the Late Jurassic of USA and Portugal. However,
since the first description the genus was used as taxonomical wastebasket to which several species were
described. We revisit three type specimens, Allosaurus fragilis YPM 1930, A. atrox YPM 1890 and A. ferox USNM
2315. We interpret the vertebral material of A. atrox and support it as a junior synonym of A. fragilis, and A. ferox
as Allosaurus indet. rather than A. fragilis.

In this paper we consider endomorphisms of an undirected cycle graph from Semigroup Theory perspective. Our main aim is to present a process to determine sets of generators with minimal cardinality for the monoids $wEnd(C_n)$ and $End(C_n)$ of all weak endomorphisms and all endomorphisms of an undirected cycle graph $C_n$ with $n$ vertices. We also describe Green's relations and regularity of these monoids and calculate their cardinalities.

In this paper we consider the monoids of all partial endomorphisms, of all partial weak endomorphisms, of all injective partial endomorphisms, of all partial strong endomorphisms and of all partial strong weak endomorphisms of a star graph with a finite number of vertices. Our main objective is to determine their ranks. We also describe their Green's relations, calculate their cardinalities and study their regularity.

In this paper we study the cyclic inverse monoid CI_n on a set Ω_n with n elements, i.e. the inverse submonoid of the symmetric inverse monoid on Ω_n consisting of all restrictions of the elements of a cyclic subgroup of order n acting cyclically on Ω_n. We show that CI_n has rank 2 (for n⩾2) and n⋅2^n−n+1 elements. Moreover, we give presentations of CI_n on n+1 generators and (n^2+3n+4)/2 relations and on 2 generators and (n^2−n+6)/2 relations. We also consider the remarkable inverse submonoid OCI_n of CI_n constituted by all its order-preserving transformations. We show that OCI_n has rank n and 3⋅2^n−2n−1 elements. Furthermore, we exhibit presentations of OCI_n on n+2 generators and (n^2+3n+8)/2 relations and on n generators and (n^2+3n)/2 relations.