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A typical 1200 mm (48 in.) wide × 200 mm (8 in.) deep prestressed concrete hollow-core floor unit is analyzed and designed as a composite slab with a 75 mm (3 in.) deep structural topping to make a comparison between Eurocode 2: Design of Concrete Structures (EC2-1-1) and the American Concrete Institute’s Building Code Requirements for Structural Concrete (ACI 318-08) and Commentary (ACI 318R- 08). This is the second of two papers. The first was published in PCI Journal in the March–April 2021 issue and designed a noncomposite hollow-core unit. The present comparison includes two-stage composite service and ultimate moments of resistance, ultimate composite shear capacities, camber and deflections, and interface shear between the hollow-core unit and cast-in-place concrete topping. Precast concrete cylin­der strength was 40 N/mm2 (5800 psi) and the cast-in-place concrete topping was 25 N/mm2 (3625 psi). The hollow-core unit was pretensioned using 10 number seven-wire helical strands. Worked examples are pre­sented in parallel formation for EC2 and ACI 318.

There has been continued global growth in tall building construction over recent years. The variation in the use of such buildings is remarkable, from lavish hotels and apartments to socially affordable units. As the world struggles to cope with growing numbers of people, dwindling resources and movements from rural to urban habitats it is unavoidable that population densities will increase, and more efficient use of scarce land will be needed. Taller buildings are the inevitable consequence. Tall buildings can use several different types of material to form their framework and envelope. Those materials are mixed to provide an optimum building solution to suit client requirements such as structure, occupancy, vision, affordability, timing, sustainability and quality. Precast concrete is one of those materials, and has been used from whole frameworks to facades, and elements mixed with structural steelwork and cast in place concrete. This state of the art report shows how precast concrete can be effectively integrated into tall buildings using modern materials and techniques, drawing on the experience and expertise that is currently available in the global precast concrete industry. The report is aimed at not only building professionals and students, but also at contractors, investors, owners, public bodies and any other parties interested in the possibilities for use of precast concrete in tall building construction. Extensive case studies at the end of the Bulletin illustrate the benefits and applications discussed in the earlier chapters.

The heterogeneous manifestations of MYH9‐related disorder (MYH9‐RD), characterized by macrothrombocytopenia, Döhle‐like inclusion bodies in leukocytes, bleeding of variable severity with, in some cases, ear, eye, kidney, and liver involvement, make the diagnosis for these patients still challenging in clinical practice. We collected phenotypic data and analyzed the genetic variants in more than 3,000 patients with a bleeding or platelet disorder. Patients were enrolled in the BRIDGE‐BPD and ThromboGenomics Projects and their samples processed by high throughput sequencing (HTS). We identified 50 patients with a rare variant in MYH9. All patients had macrothrombocytes and all except two had thrombocytopenia. Some degree of bleeding diathesis was reported in 41 of the 50 patients. Eleven patients presented hearing impairment, three renal failure and two elevated liver enzymes. Among the 28 rare variants identified in MYH9, 12 were novel. HTS was instrumental in diagnosing 23 patients (46%). Our results confirm the clinical heterogeneity of MYH9‐RD and show that, in the presence of an unclassified platelet disorder with macrothrombocytes, MYH9‐RD should always be considered. A HTS‐based strategy is a reliable method to reach a conclusive diagnosis of MYH9‐RD in clinical practice., MYH9‐related disorder diagnosis is still challenging in clinical practice. We analyzed the genetic variants in more than 3,000 patients with a bleeding or platelet disorder and identified 50 patients with a rare variant in MYH9. In the presence of an unclassified platelet disorder with macrothrombocytes, MYH9‐RD should always be considered.

The structural disorder and temperature-dependent dielectric properties of two Bi-based niobate pyrochlore systems which have both previously been reported to occur at the ideal Bi2(MIIINbV)O7 stoichiometry without any compositional disorder on the pyrochlore A site, namely the Bi2InNbO7 (BIN) and Bi2ScNbO7 (BSN) pyrochlore systems, have been carefully re-investigated. It is established that A site stoichiometric, Bi-based niobate pyrochlores can indeed exist. Electron diffraction is used to investigate the nature of the displacive disorder therein both at room temperature as well as at close to liquid nitrogen temperature. The characteristic structured diffuse scattering observed arises from β-cristobalite-like, 1-d correlated rotations and associated translations of chains of corner-connected O′Bi4 tetrahedra. The temperature-dependent dielectric properties including the low temperature dielectric relaxation properties of these A site stoichiometric, Bi-based niobate pyrochlores are also reported as are the micro-Raman spectra thereof. The experimental results suggest that the dipoles as well as the glassy relaxation behaviour in these Bi-based pyrochlores are directly related to these β-cristobalite-like, correlated rotations of 〈110〉 chains of corner-connected O′Bi4 tetrahedra.