Spectral Analysis of a Four Mode Cluster State

We theoretically evaluate the squeezed joint operators produced in a single optical parametric oscillator which generates quadripartite entangled outputs, as demonstrated experimentally by Pysher et al. \cite{pysher}[Phys. Rev. Lett. 107, 030505 (2011)]. Using a linearized fluctuation analysis we calculate the squeezing of the joint quadrature operators below threshold for a range of local oscillator phases and frequencies. These results add to the existing theoretical understanding of this potentially important system.Comment: 4 pages, 6 figure

The Herts and Minds study: feasibility of a randomised controlled trial of Mentalizationbased Treatment versus usual care to support the wellbeing of children in foster care

© The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Background: There is a lack of well-designed randomized controlled trials (RCTs) to investigate the efficacy of psychological therapies for children in foster care with emotional and behavioural difficulties. Mentalization-based therapy (MBT) focuses on supporting the carer-child relationship by promoting reflective capacity. This study examined the feasibility and acceptability of an RCT of MBT, delivered in a family-format, for children who are in foster care in the UK. Method: Herts and Minds was a phase II, blinded feasibility RCT with follow-up of at 12 and 24 weeks post-randomisation. Participants were children (age 5-16) in foster care referred to a targeted mental health service, who had some level of difficulty as identified by the Strengths and Difficulties Questionnaire (SDQ). Aims were to assess: the feasibility of recruitment processes and study uptake; capacity to train mental health practitioners to deliver MBT to an acceptable level of treatment integrity; establish acceptability and credibility of MBT as an intervention for children in foster care; establish feasibility and acceptability to participants of conducting an RCT; and estimate the likely treatment efficacy effect size. Participants were randomly allocated to either MBT (n = 15) or Usual Clinical Care (UCC) (n = 21) individually or in sibling groups. A range of qualitative and quantitative data was gathered to assess feasibility. Results: Feasibility was established with regard to: capacity to recruit participants to a study; capacity to train mental health practitioners to deliver MBT to an acceptable level of treatment integrity; acceptability and credibility of MBT; and feasibility and acceptability to participants of conducting an RCT. A number of issues made it difficult to estimate a likely treatment efficacy effect size. Conclusion: With modifications, it is feasible to run an RCT of MBT for children in foster care. Both the therapy and research design were acceptable to participants, but modifications may be needed regarding both the timing of assessments and the identification of appropriate primary outcome measures. Given the lack of evidenced based therapies for this population, such a trial would be a significant contribution to the field. Findings may be useful for other groups planning clinical trials of psychological therapies for children in foster care. Trial registration: ISRCTN 90349442. The trial was retrospectively registered on 6 May 2016.Peer reviewedFinal Published versio

Knowledge management: Philosophy, process, and pitfalls

According to a leading scholar of management James Brian Quinn,' "The capacity to manage human intellectand to transform intellectual output into a service or a group of services embodied in a product is fast becoming the critical executive skill of this era." Contrast that with the assertion by the pointy-haired boss of the Dilbert cartoon that his company's success will be driven by "redesigning processes to enable enterprise integration of knowledge resources and tools." The first is a serious, thoughtful, and eminently reasonable statement of a belief in the transformation of management. The second is a caricature of that belief, subsequently doused by Wally's response, "Is it okay if I do nothing?" Leave it to Scott Adams and his alter egos to gut the sanctity from the latest management fad

The experience of adolescents participating in a randomised clinical trial in the field of mental health: a qualitative study

Background This descriptive study aimed to investigate adolescents’ motivations for participating in a randomised controlled trial (RCT), to explore the understanding that the young people had regarding a number of aspects of the trial design, to examine whether or not they found participation in the trial to be acceptable and what affected this, and to identify whether and how the young people felt that their participation in the RCT impacted on their experience of therapy and on therapeutic change. Methods Seventy-six adolescents who were taking part in a large-scale RCT to evaluate the clinical and cost effectiveness of psychological therapies for depression were interviewed at two time-points after completing therapy. The semi-structured interviews, which included a focus on the young people’s experience of the research study, were analysed using framework analysis. Results The vast majority of adolescents found it acceptable to participate in the clinical trial, and many agreed to participate for reasons of ‘conditional altruism’. However consent was often given without great understanding of the key elements of the trial, including the difference between treatment arms and the randomisation process. Although the adolescents were largely positive about their experiences from taking part, the study raises questions about whether clinical outcomes may be influenced by participation in the research elements of the trial. Conclusions Although adolescents are under-represented in clinical trials, those who do participate are generally positive about the experience; however, careful thought needs to be given to key elements of the trial design and the potential impact of the research participation on clinical outcomes

Relationship between heavy vehicle speed limit and fleet fuel consumption on minor roads

This paper investigates the traffic-related effects of a proposal to increase the speed limit from 40 mile/h to 50 mile/h, for heavy goods vehicles greater than 7.5 tonnes, on single carriageway roads. A ‘microscopic’ single carriageway traffic simulation is developed by combining the ‘enhanced intelligent driver model’ with a single carriageway gap-acceptance passing model. Fuel consumption estimates are made using engine characteristic maps and a ‘fuel optimal’ gear selection scheme, where vehicle trajectories from the traffic simulations are taken as input drive-cycles. Traffic congestion and fleet fuel consumption are specifically addressed, though implications regarding passing behaviour and traffic safety are also noted. Results indicate that the proposed 50 mile/h heavy goods vehicles speed limit would reduce traffic congestion by over 37% and increase fleet fuel consumption by approximately 0.5 L/100 km. The authors would like to thank Justin Bishop and Niall Martin of Cambridge University Engineering Department for providing valuable data. The authors would also like to thank Rachael Dillon of Freight Transport Association for suggesting the project. This work was supported in part by the Centre for Sustainable Road Freight (SRF) and the Engineering and Physical Sciences Research Council (EPSRC) through Grant Ref EP/K00915X/1. At the time of writing, the members of the SRF were: Coca-Cola Enterprises, Denby Transport, DHL, Freight Transport Association, Haldex Brake Products, Goodyear Tires, John Lewis/Waitrose, Laing O’Rourke, Optrak, SDC Trailers, Tesco, Volvo Trucks, Warburtons, Wincanton.This is the accepted manuscript for a paper published in the Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, DOI: 10.1177/0954406215573038

Biodiversity and climate change: Risks to dwarf succulents in Southern Africa.

The aim of this study was to explore the effects of anthropogenic climate change on the dwarf succulent genus Conophytum (Aizoaceae) within areas recognised for their floral biodiversity, namely the Succulent Karoo, Fynbos, Desert and Nama Karoo biomes of South Africa and Namibia. Niche-based modelling was used to identify the key climatic and geological variables influencing the distribution of members of the genus Conophytum. The distribution of the genus is primarily controlled by a small number of environmental variables, notably winter and summer rainfall levels, together with geology. Assuming a zero-dispersal model, the predicted effect of both the A1B and A2 climatic emission scenarios was a severe contraction in the area satisfying the bioclimatic envelope for the genus coupled with significant range dislocation. Reductions of >90% in suitable habitat for 10 of the 16 taxonomic Sections that comprise the genus and represent >80% of taxa under the A2 scenario are predicted. Under A1B the projected effects are ameliorated, but reductions of >50% of habitat can be seen in a majority of Sections. Significant projected reductions in the habitable bioclimatic envelope are very likely to increase risk of extinction of ~80% of taxa even under a partly mitigated emissions scenario

Excitation dependent Fano-like interference effects in plasmonic silver nanorods

Surface plasmon resonances in metal nanoparticles are an emerging technology platform for nano-optics applications from sensing to solar energy conversion. The electromagnetic near field associated with these resonances arises from modes determined by the shape, size, and composition of the metal nanoparticle. When coupled in the near field, multiple resonant modes can interact to give rise to interference effects offering fine control of both the spectral response and spatial distribution of fields near the particle. Here, we present an examination of experimental electron energy loss spectroscopy (EELS) of silver nanorod monomer surface plasmon modes and present an explanation of observed spatial amplitude modulation of the Fabry-Pérot resonance modes of these silver nanorods using electrodynamics simulations. For these simulations, we identify differences in spectral peak symmetry in light scattering and electron spectroscopies (EELS and cathodoluminescence) and analyze the distinct near-field responses of silver nanorods to plane-wave light and electron beam excitation in terms of a coupled oscillator model. Effects of properties of the material and the incident field are evaluated, and the spatially resolved EELS signals are shown to provide a signature for assessing Fano-like interference effects in silver nanorods. These findings outline key considerations and challenges for interpreting electron microscopy data on plasmonic nanoparticles for understanding nanoscale optics and for characterization and design of photonic devices.S.M.C. acknowledges support of a Gates Cambridge Scholarship. D.R. acknowledges support from the Royal Society's Newton International Fellowship scheme. We acknowledge the use of computing facilities provided by CamGrid. Parts of this work were also performed using the Darwin Supercomputer of the University of Cambridge High Performance Computing Service (http://www.hpc.cam.ac.uk/), provided by Dell Inc. using Strategic Research Infrastructure Funding from the Higher Education Funding Council for England and funding from the Science and Technology Facilities Council. We thank F.J. de la Peña for helpful discussions on the use of hyperspy. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Program (Grant No. FP7/2007-2013)/ERC Grant Agreement No. 291522-3DIMAGE. Data on rod “B” were acquired by one of us (D. Rossouw) with support of a NSERC Discovery Grant (G. A. Botton) at the Canadian Centre for Electron Microscopy, a national facility supported by NSERC and McMaster University. We thank G. A. Botton for access to data on rod “B” and for helpful comments on this manuscript. P.A.M. also acknowledges funding from the European Union's Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2)

Coupling curvature to a uniform magnetic field; an analytic and numerical study

The Schrodinger equation for an electron near an azimuthally symmetric curved surface $\Sigma$ in the presence of an arbitrary uniform magnetic field $\mathbf B$ is developed. A thin layer quantization procedure is implemented to bring the electron onto $\Sigma$, leading to the well known geometric potential $V_C \propto h^2-k$ and a second potential that couples $A_N$, the component of $\mathbf A$ normal to $\Sigma$ to mean surface curvature, as well as a term dependent on the normal derivative of $A_N$ evaluated on $\Sigma$. Numerical results in the form of ground state energies as a function of the applied field in several orientations are presented for a toroidal model.Comment: 12 pages, 3 figure