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Buildings are major contributors of carbon emissions and related global warming. Emissions occur along all building stages, from a whole-life perspective, including material production, construction processes, building operations, maintenance and end-of-life processes. Upfront emissions include processes before building operations. They can be influenced immediately and will have a positive effect today. However, mitigation potentials during the construction stage are often overseen in research. This study presents an analysis of the carbon emissions of 61 Danish construction sites based on their energy consumption, waste production (module A5) and transport to site (A4). The results show carbon emissions for A4 of 0.28 and for A5 of 1.00 kgCO2e/m2 gross floor area per year over 50 years. This is 13.47% of the Danish whole-life carbon reference of 9.50 kgCO2e/m2y, which includes the product stage (A1–3), replacements (B4), operational energy use (B6) and waste processes and disposal (C3–4). Almost half of the emissions are related to construction waste followed by electricity, heat and fuel. Floor area and building use have not shown to be influential for carbon emissions, suggesting other parameters are more important. The significance of modules A4 and A5 suggests implementing them in future whole-life carbon assessments and related policies. This paper also demonstrates the development of generic emission coefficients, which are suited to increase the feasibility for application in the building industry. Finally, the usability of module A4 and A5 in environmental product declarations is discussed.

Magnetic reconnection in current sheets is a magnetic-to-particle energy conversion process that is fundamental to many space and laboratory plasma systems. In the standard model of reconnection, this process occurs in a minuscule electron-scale diffusion region 1 , 2 . On larger scales, ions couple to the newly reconnected magnetic-field lines and are ejected away from the diffusion region in the form of bi-directional ion jets at the ion Alfvén speed 3 – 5 . Much of the energy conversion occurs in spatially extended ion exhausts downstream of the diffusion region 6 . In turbulent plasmas, which contain a large number of small-scale current sheets, reconnection has long been suggested to have a major role in the dissipation of turbulent energy at kinetic scales 7 – 11 . However, evidence for reconnection plasma jetting in small-scale turbulent plasmas has so far been lacking. Here we report observations made in Earth’s turbulent magnetosheath region (downstream of the bow shock) of an electron-scale current sheet in which diverging bi-directional super-ion-Alfvénic electron jets, parallel electric fields and enhanced magnetic-to-particle energy conversion were detected. Contrary to the standard model of reconnection, the thin reconnecting current sheet was not embedded in a wider ion-scale current layer and no ion jets were detected. Observations of this and other similar, but unidirectional, electron jet events without signatures of ion reconnection reveal a form of reconnection that can drive turbulent energy transfer and dissipation in electron-scale current sheets without ion coupling. Observations of electron-scale current sheets in Earth’s turbulent magnetosheath reveal electron reconnection without ion coupling, contrary to expectations from the standard model of magnetic reconnection.

Objective Infraspinatus syndrome (IS) results from injury to the suprascapular nerve. For reasons that are poorly understood, volleyball players are at greater risk of developing IS than are athletes who compete in other overhead sports. Differences between the shoulder kinematics of volleyball-related overhead skills and those skills demanded by other overhead sports might explain the pronounced prevalence of IS among volleyball athletes. Design Observational, laboratory-based, cross-sectional study. Setting The American Sports Medicine Institute. Participants Fourteen healthy female Division 1 collegiate volleyball athletes. Methods Upper limb biomechanics of 14 healthy female Division 1 collegiate volleyball athletes while spiking and serving were quantified, then compared to the results from data previously obtained from female baseball pitchers and tennis players. Results Although the general movement pattern at the shoulder girdle is qualitatively similar for the upper limb skills required by a variety of overhead sports, volleyball spiking and serving result in greater shoulder abduction and horizontal adduction at the moment of ball contact/release than do baseball pitching or tennis serving. Conclusion The authors suggest that the unique scapular mechanics which permit the extreme shoulder abduction and horizontal adduction that characterise volleyball spiking and serving place anatomically predisposed volleyball athletes at increased risk for developing cumulative traction-related injury to the suprascapular nerve at the level of the spinoglenoid notch.