{Crocodylomorphs were a diverse clade in the Late Jurassic of Portugal, with six taxa reported to date. Here we describe 126 isolated teeth recovered by screen-washing of sediments from Valmitão (Lourinhã, Portugal, late Kimmeridgian–Tithonian), a vertebrate microfossil assemblage in which at least five distinct crocodylomorph taxa are represented. Ten morphotypes are described and attributed to five clades (Lusitanisuchus, Atoposauridae, Goniopholididae, Bernissartiidae and an undetermined mesoeucrocodylian). Four different ecomorphotypes are here proposed according to ecological niches and feeding behaviours: these correspond to a diet based on arthropods and small vertebrates (Lusitanisuchus and Atoposauridae), a generalist diet (Goniopholididae), a durophagous diet (Bernissartiidae) and a carnivorous diet. Lusitanisuchus mitracostatus material from Guimarota is here redescribed to achieve a better illustration and comparison with the new material.This assemblage shares similar ecomorphotypes with other Mesozoic west-central European localities, where a diversity of crocodylomorphs lived together, avoiding direct ecological competition through niche partitioning. The absence of large marine crocodylomorphs, present in other contemporaneous assemblages, is here interpreted as evidence that the Valmitão assemblage was deposited in a freshwater environment, although sample bias cannot be completely ruled out. These affinities are further supported by the presence of lanceolate and leaf-shaped teeth associated with continental clades.}

Three new additional skull specimens of Talarurus plicatospineus have been recovered from the Upper Cretaceous (Cenomanian–Santonian) Bayanshiree Formation, of Bayan Shiree cliffs, eastern Gobi Desert, Mongolia. The skulls feature unique characters such as an anteriorly protruded single internarial caputegulum, around 20 flat or concave nasal-area caputegulae surrounded by a wide sulcus, a vertically oriented elongate loreal caputegulum with a pitted surface, an elongate lacrimal caputegulum positioned above the posterodorsal border of the maxilla, two longitudinally arranged large frontoparietal caputegulae surrounded by smaller rhomboid caputegulae, small but elongate medial supraorbital caputegulae, a posterior supraorbital caputegulum that is four times larger than the anterior one, up to three transverse parallel grooves on the dorsal surface of the posterior supraorbital caputegulum, postocular caputegulae along the ventral to posterior rim of the orbit that extend almost to the anteroventral margin of the squamosal horn, a longitudinal furrow tapering towards the apex of the squamosal horn, a lateral nuchal caputegulum four to five times larger than other nuchal caputegulae, and a pterygovomerine keel with a ventral margin that is dorsally positioned to the alveolar ridge. The phylogenetic analysis result showed that Talarurus is sister to the clade that includes the derived Asian ankylosaurines (Saichania chulsanensis, Tarchia kielanae, and Zaraapelta nomadis). It also shows that there was dispersal of ankylosaurines from Asia into western North America before the Cenomanian. Moreover, the rostral differences between Talarurus and Tsagantegia, another ankylosaur from the same formation, suggest possible niche partitioning between these taxa.

In the current literature we can find mainly two approaches to the
SDE regime switching modeling. The traditional one, the externally induced
regime switching diffusions is described by the switching being derived from
a separate continuous time Markov process, with a finite, or denumerable,
state space { indexing the regimes { the random times of the regime switches
being exactly the jump times of the finite valued Markov process. There is a
first alternative approach in which the regime switching occurs whenever the
trajectory enters in some prescribed region on the state space; the regions we
consider will be mainly open intervals defined by unknown thresholds for the
trajectories; thresholds that, in principle, should also be estimated. In this
approach the partitioning of the the state space is already defined in the drift
and volatility of the SDE. In a second alternative approach the switching occurs
in a random way but at some random times defined when the trajectories hit
some prescribed thresholds, that again, must be estimated. We may designate
these two alternative approaches as auto-induced regime switching diffusions
as there is no external noise source to force the switching occurrence. We prove
a generalization of an existence result of the existence of auto-induced regime
switching SDE solutions for irregular coefficients and a result that encompasses
some of the cases of both externally and auto-induced regime switching SDE
solutions.

Mathematics has a strong presence in the school curriculum, often justified by its usefulness in social life, in the world of work and by its connections with other sciences. This interdisciplinary connection, in particular when it requires constructing and refining mathematical models and discussing their applications to solve problems of other sciences, can assist students to understand why mathematics is so important in school. In the development of interdisciplinary activities, the characteristics of the tasks emerge as an important aspect. The emphasis is on the use of technological materials and the way they can support the development of concepts, provide different representations and support deeper understandings, and offer a multifaceted support to collect data and simulate experiences. Based on these assumptions, the aim of this chapter is to present, analyse and discuss tasks that promote interdisciplinary technological approaches from a mathematical point of view. In this chapter we assume interdisciplinarity as a complex construct, and in order to clarify its meaning we will discuss several types of conceptions, from multidisciplinary, to interdisciplinary, and to transdisciplinary. We will then address related concepts, such as modelling and STEM, highlighting similarities and differences between them, to reach an understanding of interdisciplinarity. In the process of the interdiciplinary approach, digital technologies arise as a central element. Based on a set of tasks on mathematics and on different sciences, we discuss what can change on an interdisciplinary approach to the teaching and learning of mathematical content and on the articulation between subjects.

We present a new algorithm for solving large-scale unconstrained optimization problems that uses cubic models, matrix-free subspace minimization, and secant-type parameters for defining the cubic terms. We also propose and analyze a specialized trust-region strategy to minimize the cubic model on a properly chosen low-dimensional subspace, which is built at each iteration using the Lanczos process. For the convergence analysis we present, as a general framework, a model trust-region subspace algorithm with variable metric and we establish asymptotic as well as complexity convergence results. Preliminary numerical results, on some test functions and also on the well-known disk packing problem, are presented to illustrate the performance of the proposed scheme when solving large-scale problems.

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High-strength concrete (HSC) slab-column connections with relatively low concrete strengths compared to today’s capabilities have been tested under seismic-type loading in the past. Herein, the hybrid use of HSC with compressive strength approximately 120 MPa and normal-strength concrete (NSC) is investigated through three reversed horizontal cyclic-loading tests with different geometries of the HSC region and a reference NSC specimen. The results show that HSC applied in the vicinity of the column can significantly enhance the seismic performance of slab-column connections. The best result in terms of drift capacity and economic use of HSC was achieved in the case of full-depth HSC extended from the column’s face up to 2.5 times the effective depth. Drift ratios up to 3.0% were achieved. A comparison with previous tests showed that the hybrid use of HSC and NSC can achieve similar results to the provision of punching shear reinforcement.

Abstract Fiber reinforced polymer (FRP) composites can be efficient for flexural strengthening of flat slabs if debonding of the FRP is postponed. However, with the increase of the flexural capacity, the flat slab becomes more susceptible to punching shear failure. In this context, four flexural or simultaneous flexural and punching shear retrofitting systems are investigated in this study to strengthen a flexure-deficient flat slab. Externally Bonded Reinforcement on Grooves (EBROG) and externally bonded reinforcement (EBR) methods are used for flexural strengthening in two cases: slabs without punching shear reinforcement and with post-installed shear bolts as shear reinforcement. According to the results, flexural strengthening of the slab using the EBR and EBROG techniques increased its load capacity by 12% and 21%, respectively. Simultaneous flexural and shear strengthening of the slab using the EBROG technique was the most effective, leading to a 57% enhancement of the load capacity. For specimens whose failure was governed by punching, comparing the results with code predictions showed that Eurocode and ACI (and the respective guide documents fib bulletin 90 and ACI 440.2R) overestimated the capacity of these specimens. In cases where failure was governed by flexure, a simple application of the yield line theory predicted reasonably well the load capacity of the specimens.

Abstract This paper presents a critical review of the state of the art of experimental research concerning the seismic response of reinforced concrete flat slab frames. After a summary of tests on connections, the paper examines tests carried out on frames with gravity and cyclic lateral loading, and shake table tests; scaled specimens and one real scale study are included. A discussion of the results reached so far is provided focusing on the global response, the different load types and effects; the ultimate rotations at failure in relation to the gravity shear and a classification of different failure modes for different types of connections. Based on this analysis, the research needs are highlighted. An experimental program launched to address these open questions is described. Further open topics are highlighted.

Herein, we present a selection of sustainable amidation processes, that have contributed to solving the problems associated with traditional methods. Novel reagents and methods are described, including boron‐based reagents, the use of metallic and organometallic catalysts as well as metal‐free methods using milder and versatile oxidants.

The aim of the paper is to present and analyse the case of one teacher attempting to introduce his students to fractals using digital technology. His task design process has been made explicit through the writing of a storyboard. It has been analysed in order to focus on the stages of the process, identifying prominent elements in it by using the knowledge quartet framework. Results can be useful to inform teacher educators about his needs with respect to the development of his ability in task design. The importance of this aspect, particularly worth of note in the digital age in which teachers have many opportunities to access teaching resources online, has been amplified by the constraints to which educational systems have been subjected during the Covid-19 pandemic emergency.

The lithostratigraphy of the Triassic deposits of the Jameson Land Basin in central East Greenland is revised. The new Scoresby Land Supergroup is now composed of the Wordie Creek, Pingo Dal, Gipsdalen and Fleming Fjord Groups. This paper only deals with the lithostratigraphy of the late Early-Late Triassic continental deposits of the latter three groups with emphasis on the vertebratebearing Fleming Fjord Group. The new Pingo Dal Group consists of three new formations, the Rødstaken, Paradigmabjerg and Klitdal Formations (all elevated from members), the new Gipsdalen Group consists of three new formations, the Kolledalen, Solfaldsdal (with the new Gråklint Member) and Kap Seaforth Formations (all elevated from members), and the new Fleming Fjord Group is subdivided into three new formations, the Edderfugledal, Malmros Klint and Ørsted Dal Formations (all elevated from members). The Edderfugledal Formation contains two cyclic bedded, lacustrine members, a lowermost Sporfjeld Member (elevated from beds), and an uppermost Pingel Dal Member (elevated from beds). The lacustrine red beds of the Malmros Klint Formation are not subdivided. The lacustrine and fluvial Ørsted Dal Formation contains three new members. In the eastern and central part of the basin, the formation is initiated by cyclic bedded, red lacustrine mudstones of the Carlsberg Fjord Member (elevated from beds), while in the northwestern part of the basin the lowermost part of the formation is composed of grey fluvial conglomerates and sandstones with subordinate red mudstones of the Bjergkronerne Member (elevated from beds). The uppermost part of the formations in most of the basin is composed of cyclic bedded, variegated lacustrine mudstones and grey to yellowish marlstones of the Tait Bjerg Member (elevated from beds). The sediments in the Fleming Fjord Group contain remains of a rich and diverse vertebrate fauna including dinosaurs, amphibians, turtles, aeotosaurs, pterosaurs, phytosaurs and mammaliaforms. Most vertebrate bones have been found in uppermost Malmros Klint Formation, and in the Carlsberg Fjord and Tait Bjerg Members. The Norian–early Rhaetian, lacustrine Fleming Fjord Group was deposited at about 41° N on the northern part of the supercontinent Pangaea. Lacustrine sedimentation was controlled by seasonal as well as longer-term (orbital) variation in precipitation. Precipitation was probably brought to the basin by southwesterly winds. The lacustrine sediments of the uppermost Fleming Fjord Group show deposition during increasingly humid conditions changing the lake environment from an ephemeral lake-steppe area to a perennial lake. This evolution of lake environment suggests a change from a winter-wet temperate climate to one with precipitation throughout the year.

Abstract An experimental work on reinforced concrete flat slab specimens to test the efficiency of postinstalled bolts, as punching shear reinforcement in resisting vertical and cyclic horizontal loads, was conducted and is presented in this paper. The test protocol consisted in increasing horizontal drifts combined with constant vertical load until failure. Two different detailing solutions for the shear reinforcement were considered, one using a radial distribution around the column and another using a cross distribution, being the results compared with a previously tested reference specimen. The dimensions of the specimens were 4.25 x 1.85 x 0.15 m3. The test setup used for these tests was developed by the research team and simulates the boundary conditions with already recognized good results. Postinstalled steel bolts were proven to be an efficient solution for strengthening of existing structures, improving the structural behavior, and the punching resistance.