Selective ortho‐Functionalization of Adamantylarenes Enabled by Dispersion and an Air‐Stable Palladium(I) Dimer

Contrary to the general belief that Pd‐catalyzed cross‐coupling at sites of severe steric hindrance are disfavored, we herein show that the oxidative addition to C?Br ortho to an adamantyl group is as favored as the corresponding adamantyl‐free system due to attractive dispersion forces. This enabled the development of a fully selective arylation and alkylation of C?Br ortho to an adamantyl group, even if challenged with competing non‐hindered C?OTf or C?Cl sites. The method makes use of an air‐stable Pd^I dimer and enables straightforward access to diversely substituted therapeutically important adamantylarenes in 5–30 min.     

Structural portrait of filamin interaction mechanisms

We review the most recent findings on human filamin structure, with particular emphasis on the relationships between structure, function, and interaction. Filamin is a cytoskeletal actin-binding protein and it is therefore crucial in providing cells with the necessary mechanical and dynamical properties. Filamentous actin cross-linking by filamin is regulated by a number of other proteins and the molecular mechanisms of this complex interaction network can be understood by highlighting the structural features of isolated filamin moieties and of their complexes with several partners. Here we describe first the structure-function relationships of the isolated filamin, its flexibility, and its dimerization mechanism. Secondly, we illustrate the structural mechanism with which filamin can recognize its partners, both the actin filaments and the regulatory proteins.     

Analysis of elements that support implementation of high-quality engineering design within the elementary classroom

One model of engineering integration that has shown promise is the use of engineering design as a context to support teachers as they conceptualize and plan integrated STEM lessons. However, integrating engineering into science instruction presents a number of challenges, especially at the elementary level, and the implementation of high-quality engineering design-based instruction is not often what is actualized in the classroom. This study investigated how teachers operationalized an engineering design-based lesson in their classroom by examining what elements of engineering teachers chose to include within in their lesson plan and enact in the classroom. Participants included 20 triads composed of teachers, student teachers, and engineering graduate students. Utilizing a multiple case study approach, this study found that there were four main groupings related to how teachers operationalized engineering design-based instruction in their classrooms. Results suggest that even though there were several engineering design elements that were included in a majority of the lesson plans, such as context, constraints, materials exploration, and building, and testing solutions, some characteristics were found to be more influential than others when looking at how to help teachers to implement high-quality engineering design-based instruction.     

On the hyperbolic unitary geometry

Hans Cuypers (Preprint) describes a characterisation of the geometry on singular points and hyperbolic lines of a finite unitary space—the hyperbolic unitary geometry—using information about the planes. In the present article we describe an alternative local characterisation based on Cuypers’ work and on a local recognition of the graph of hyperbolic lines with perpendicularity as adjacency. This paper can be viewed as the unitary analogue of the second author’s article (J. Comb. Theory Ser. A 105:97–110, 2004) on the hyperbolic symplectic geometry.     

Ion-selective Membranes Prepared Upon Layer-by-Layer Assembly of Azamacrocycles and Polyelectrolytes

Summary : Recent studies on ion transport across multilayered membranes of azamacrocycles and polyelectrolytes are reviewed. Membranes were built up on porous PAN/PET supports using electrostatic layer-by-layer assembly. Two types of separation membranes were prepared, type I consisting of protonated hexaazacyclooctadecane and polyvinylsulfate, and type II of hexaazacyclo-octadecane hexaacetic acid and protonated polyvinylamine. Ion transport was studied under dialysis, nanofiltration and reverse osmosis conditions. Type I membranes were suitable for efficient separation of mono- and divalent anions, whereas type II membranes were suited for separation of mono- from di- and trivalent cations.     

Bringing brain imaging to the school to assess arithmetic problem solving: chances and limitations in combining educational and neuroscientific research

Scientific collaboration between neuroscience and mathematics education has mostly focused on brain imaging trying to inform education. This study aims at meeting expectations of both research fields, thus enhancing the ecological validity. We investigated the influence of age, mathematical competency, and task characteristics (format, complexity) on students’ arithmetic performance. Based on behavioral data from a pilot study (n = 73), arithmetic tasks were chosen for a subsequent investigation (n = 90), in which parietal brain activation was measured with near-infrared spectroscopy. Substantial group differences in calculation time were observed. While task characteristics influenced arithmetic performance in both age groups, this influence was much smaller for grade 8 students. However, parietal brain activation during calculation was not affected by age, mathematical competency, or task characteristics. Limitations of the experimental design and general problems of applying imaging methods to the school context are discussed.