Mapping the coevolution of urban energy systems: pathways of change

Abstract. The interface of a long-standing movement for sustainability at the urban scale and the imperatives of the carbon-reduction agenda are driving change in urban energy systems. This paper seeks to address the nature of that change and, in particular, to consider how different pathways of change are emerging. To do this it draws on the coevolution and pathways literatures to interrogate a database of current urban energy initiatives within the UK. This analysis reveals the multiple pathways of change though which new modes of energy production and consumption are being developed to deliver carbon reductions through the reconfiguring of urban energy systems. The paper concludes with a discussion of the implications of these changes for urban governance and for carbon reductions

A multi-scalar perspective on health and urban housing: an umbrella review

With more than half the world’s population living in cities, understanding how the built environment impacts human health at different urban scales is crucial. To be able to shape cities for health, an understanding is needed of planetary health impacts, which encompass the human health impacts of human-caused disruptions on the Earth’s natural ecosystems. This umbrella review maps health evidence across the spatial scales of the built environment (building; neighbourhood; and wider system, including city, regional and planetary levels), with a specific focus on urban housing. Systematic reviews published in English between January 2011 and December 2020 were searched across 20 databases, with 1176 articles identified and 124 articles screened for inclusion. Findings suggests that most evidence reports on health determinants at the neighbourhood level, such as greenspace, physical and socio-economic conditions, transport infrastructure and access to local services. Physical health outcomes are also primarily reported, with an emerging interest in mental health outcomes. There is little evidence on planetary health outcomes and significant gaps in the research literature are identified. Based on these findings, three potential directions are identified for future research

Strong field physics and QED experiments with ELI-NP 2×10PW laser beams

The ELI-NP facility will focus a 10 PW pulsed laser beam at intensities of ∼10 23 W/cm 2 for the first time, enabling investigation of the new physical phenomena at the interfaces of plasma, nuclear and particle physics. The electric field in the laser focus has a maximum value of ∼10 15 V/m at such laser intensities. In the ELI-NP Experimental Area E6, we propose the study of Radiation Reaction, Strong Field Quantum Electrodynamics (QED) effects and resulting production of Ultra-bright Sources of Gamma-rays which could be used for nuclear activation. Two powerful, synchronized 10 PW laser beams will be focused in the E6 Interaction Chamber on either gas or solid targets. One 10 PW beam is the Pump-beam and the other is the Probe-beam. The focused Pump beam accelerates the electrons to relativistic energies. The accelerated electron bunches interact with the very high electro-magnetic field of the focused Probe beam. The layout of the experimental area E6 will be presented with several options for the experimental configurations

Urinary Malondialdehyde (MDA) Concentrations in the General Population-A Systematic Literature Review and Meta-Analysis.

Oxidative stress has been associated with various inflammation-related human diseases. It is defined as an imbalance between the production and elimination of reactive oxygen species (ROS). ROS can oxidize proteins, lipids, and DNA, and some of these oxidized products are excreted in urine, such as malondialdehyde (MDA), which is considered a biomarker for oxidative damage of lipids. To interpret changes of this biomarker as a measure of oxidative species overproduction in humans, a background range for urinary MDA concentration in the general population is needed. We sought to establish urinary MDA concentration ranges for healthy adult populations based on reported values in the available scientific literature. We conducted a systematic review and meta-analysis using the standardized protocol registered in PROSPERO (CRD42020146623). EMBASE, PubMed, Web of Science, and Cochrane library databases were searched from journal inception up to October 2020. We included 35 studies (divided into 47 subgroups for the quantitative analysis). Only studies that measured creatinine-corrected urinary MDA with high-performance liquid chromatography (HPLC) with mass spectrometry (MS), fluorescence detection, or UV photometry were included. The geometric mean (GM) of urinary MDA concentration was 0.10 mg/g creatinine and 95% percentile confidence interval (CI) 0.07-0.12. Age, geographical location but not sex, and smoking status had a significant effect on urinary MDA concentrations. There was a significant increasing trend of urinary MDA concentrations with age. These urinary MDA values should be considered preliminary, as they are based on mostly moderate to some low-quality evidence studies. Although urinary MDA can reliably reflect excessive oxidative stress in a population, the influence of physiological parameters that affect its meaning needs to be addressed as well as harmonizing the chemical analytical methods

Are we ready to transfer optical light to gamma-rays?

Scattering relativistic electrons with optical lasers can result in a significant frequency upshift for the photons, potentially producing $\gamma$-rays. This is what linear Compton scattering taught us. Ultra-intense lasers offer nowadays a new paradigm where multi-photon absorption effects come into play. These effects can result in higher harmonics, higher yields and also electron-positron pairs. This article intends to discriminate the different laser scenarios that have been proposed over the past years as well as to give scaling laws for future experiments. The energy conversion from laser or particles to high-frequency photons is addressed for both the well-known counter propagating electron beam-laser interaction and for Quantum-electrodynamics cascades triggered by various lasers. Constructing bright and energetic gamma-ray sources in controlled conditions is within an ace of seeing the light of day.Comment: 9 pages, 9 figure

Developing a programme theory for a transdisciplinary research collaboration: Complex Urban Systems for Sustainability and Health [version 1; peer review: 2 approved]

Background: Environmental improvement is a priority for urban sustainability and health and achieving it requires transformative change in cities. An approach to achieving such change is to bring together researchers, decision-makers, and public groups in the creation of research and use of scientific evidence. / Methods: This article describes the development of a programme theory for Complex Urban Systems for Sustainability and Health (CUSSH), a four-year Wellcome-funded research collaboration which aims to improve capacity to guide transformational health and environmental changes in cities. / Results: Drawing on ideas about complex systems, programme evaluation, and transdisciplinary learning, we describe how the programme is understood to “work” in terms of its anticipated processes and resulting changes. The programme theory describes a chain of outputs that ultimately leads to improvement in city sustainability and health (described in an ‘action model’), and the kinds of changes that we expect CUSSH should lead to in people, processes, policies, practices, and research (described in a ‘change model’). / Conclusions: Our paper adds to a growing body of research on the process of developing a comprehensive understanding of a transdisciplinary, multiagency, multi-context programme. The programme theory was developed collaboratively over two years. It involved a participatory process to ensure that a broad range of perspectives were included, to contribute to shared understanding across a multidisciplinary team. Examining our approach allowed an appreciation of the benefits and challenges of developing a programme theory for a complex, transdisciplinary research collaboration. Benefits included the development of teamworking and shared understanding and the use of programme theory in guiding evaluation. Challenges included changing membership within a large group, reaching agreement on what the theory would be ‘about’, and the inherent unpredictability of complex initiatives

The future of the planning system in England: Written evidence submitted by the Bartlett School of Planning, University College London

This document is the response from nineteen academics based at the Bartlett School of Planning, University College London (UCL) to the government’s White Paper Planning for the Future. The Bartlett School of Planning is one of the world’s leading centres for planning education and research. This response draws on the research and understanding of scholars with considerable relevant expertise across planning, urban design and real estate

Electron spin polarization in realistic trajectories around the magnetic node of two counter-propagating, circularly polarized, ultra-intense lasers

It has recently been suggested that two counter-propagating, circularly polarized, ultra-intense lasers can induce a strong electron spin polarization at the magnetic node of the electromagnetic field that they setup (Del Sorbo et al 2017 Phys. Rev. A 96 043407). We confirm these results by considering a more sophisticated description that integrates over realistic trajectories. The electron dynamics is weakly affected by the variation of power radiated due to the spin polarization. The degree of spin polarization differs by approximately 5% if considering electrons initially at rest or already in a circular orbit. The instability of trajectories at the magnetic node induces a spin precession associated with the electron migration that establishes an upper temporal limit to the polarization of the electron population of about one laser period

A simple electron time-of-flight spectrometer for ultrafast vacuum ultraviolet photoelectron spectroscopy of liquid solutions

We present a simple electron time of flight spectrometer for time resolved photoelectron spectroscopy of liquid samples using a vacuum ultraviolet (VUV) source produced by high-harmonic generation. The field free spectrometer coupled with the time-preserving monochromator for the VUV at the Artemis facility of the Rutherford Appleton Laboratory achieves an energy resolution of 0.65 eV at 40 eV with a sub 100 fs temporal resolution. A key feature of the design is a differentially pumped drift tube allowing a microliquid jet to be aligned and started at ambient atmosphere while preserving a pressure of 10−1 mbar at the micro channel plate detector. The pumping requirements for photoelectron (PE) spectroscopy in vacuum are presented while the instrument performance is demonstrated with PE spectra of salt solutions in water. The capability of the instrument for time resolved measurements is demonstrated by observing the ultrafast (50 fs) vibrational excitation of water leading to temporary proton transfer