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The high-precision X-ray diffraction setup for work with diamond anvil cells (DACs) in interaction chamber 2 (IC2) of the High Energy Density instrument of the European X-ray Free-Electron Laser is described. This includes beamline optics, sample positioning and detector systems located in the multipurpose vacuum chamber. Concepts for pump-probe X-ray diffraction experiments in the DAC are described and their implementation demonstrated during the First User Community Assisted Commissioning experiment. X-ray heating and diffraction of Bi under pressure, obtained using 20 fs X-ray pulses at 17.8 keV and 2.2 MHz repetition, is illustrated through splitting of diffraction peaks, and interpreted employing finite element modeling of the sample chamber in the DAC.

H2O transforms to two forms of superionic (SI) ice at high pressures and temperatures, which contain highly mobile protons within a solid oxygen sublattice. Yet the stability field of both phases remains debated. Here, we present the results of an ultrafast X-ray heating study utilizing MHz pulse trains produced by the European X-ray Free Electron Laser to create high temperature states of H2O, which were probed using X-ray diffraction during dynamic cooling. We confirm an isostructural transition during heating in the 26-69 GPa range, consistent with the formation of SI-bcc. In contrast to prior work, SI-fcc was observed exclusively above ~50 GPa, despite evidence of melting at lower pressures. The absence of SI-fcc in lower pressure runs is attributed to short heating timescales and the pressure-temperature path induced by the pump-probe heating scheme in which H2O was heated above its melting temperature before the observation of quenched crystalline states, based on the earlier theoretical prediction that SI-bcc nucleates more readily from the fluid than SI-fcc. Our results may have implications for the stability of SI phases in ice-rich planets, for example during dynamic freezing, where the preferential crystallization of SI-bcc may result in distinct physical properties across mantle ice layers. The authors perform heating experiments using femtosecond X-ray free electron laser pulses to explore the phase stability of superionic H2O. The absence of a face-centered cubic phase below 50 GPa, where superionic ice forms from the melt, is attributed to the short heating time and may help understanding the stability of superionic phases in ice-rich planets. [ABSTRACT FROM AUTHOR]

Experiments accessing extreme conditions at x-ray free electron lasers (XFELs) involve rapidly evolving conditions of temperature. Here, we report time-resolved, direct measurements of temperature using spectral streaked optical pyrometry of x-ray and optical laser-heated states at the High Energy Density instrument of the European XFEL. This collection of typical experiments, coupled with numerical models, outlines the reliability, precision, and meaning of time dependent temperature measurements using optical emission at XFEL sources. Dynamic temperatures above 1500 K are measured continuously from spectrally- and temporally-resolved thermal emission at 450–850 nm, with time resolution down to 10–100 ns for 1–200 μ s streak camera windows, using single shot and integrated modes. Targets include zero-pressure foils free-standing in air and in vacuo, and high-pressure samples compressed in diamond anvil cell multi-layer targets. Radiation sources used are 20-fs hard x-ray laser pulses at 17.8 keV, in single pulses or 2.26 MHz pulse trains of up to 30 pulses, and 250-ns infrared laser single pulses. A range of further possibilities for optical measurements of visible light in x-ray laser experiments using streak optical spectroscopy are also explored, including for the study of x-ray induced optical fluorescence, which often appears as background in thermal radiation measurements. We establish several scenarios where combined emissions from multiple sources are observed and discuss their interpretation. Challenges posed by using x-ray lasers as non-invasive probes of the sample state are addressed. [ABSTRACT FROM AUTHOR]

Dolores P Langford,1,2 Lena Fleig,3–5 Kristin C Brown,3,4 Nancy J Cho,1,2 Maeve Frost,1 Monique Ledoyen,1 Jayne Lehn,1 Kostas Panagiotopoulos,1,6 Nina Sharpe,1 Maureen C Ashe3,4 1Vancouver Coastal Health, 2Department of Physical Therapy, The University of British Columbia (UBC), 3Department of Family Practice, The University of British Columbia (UBC), 4Centre for Hip Health and Mobility, Vancouver, BC, Canada; 5Freie Universität Berlin, Health Psychology, Berlin, Germany; 6Department of Orthopaedics, The University of British Columbia (UBC), Vancouver, BC, Canada Objectives: Our primary aim of this pilot study was to test feasibility of the planned design, the interventions (education plus telephone coaching), and the outcome measures, and to facilitate a power calculation for a future randomized controlled trial to improve adherence to recovery goals following hip fracture.Design: This is a parallel 1:1 randomized controlled feasibility study.Setting: The study was conducted in a teaching hospital in Vancouver, BC, Canada.Participants: Participants were community-dwelling adults over 60 years of age with a recent hip fracture. They were recruited and assessed in hospital, and then randomized after hospital discharge to the intervention or control group by a web-based randomization service. Treatment allocation was concealed to the investigators, measurement team, and data entry assistants and analysts. Participants and the research physiotherapist were aware of treatment allocation.Intervention: Intervention included usual care for hip fracture plus a 1-hour in-hospital educational session using a patient-centered educational manual and four videos, and up to five postdischarge telephone calls from a physiotherapist to provide recovery coaching. The control group received usual care plus a 1-hour in-hospital educational session using the educational manual and videos.Measurement: Our primary outcome was feasibility, specifically recruitment and retention of participants. We also collected selected health outcomes, including health-related quality of life (EQ5D-5L), gait speed, and psychosocial factors (ICEpop CAPability measure for Older people and the Hospital Anxiety and Depression Scale).Results: Our pilot study results indicate that it is feasible to recruit, retain, and provide follow-up telephone coaching to older adults after hip fracture. We enrolled 30 older adults (mean age 81.5 years; range 61–97 years), representing a 42% recruitment rate. Participants excluded were those who were not community dwelling on admission, were discharged to a residential care facility, had physician-diagnosed dementia, and/or had medical contraindications to participation. There were 27 participants who completed the study: eleven in the intervention group, 15 in the control group, and one participant completed a qualitative interview only. There were no differences between groups for health measures.Conclusion: We highlight the feasibility of telephone coaching for older adults after hip fracture to improve adherence to mobility recovery goals. Keywords: feasibility, recruitment, hip fracture, telephone follow-up, patient education, coaching

Michael Frost,1 John Hulbert2 1Minnesota Epilepsy Group, PA, St Paul, MN, USA; 2Urologic Physicians, PA, Edina, MN, USA Abstract: Tuberous sclerosis complex (TSC) is a genetic disorder characterized by nonmalignant tumors (hamartomas) that can occur in various organ systems, including the brain, kidneys, lungs, skin, eyes, and heart. Clinical manifestations of TSC can occur at any age, thereby making the diagnosis difficult. No typical disease presentation is known, and the clinical presentation usually differs between pediatric and adult patients. Furthermore, variable penetrance of the genetic mutation causes a range of disease severity from very mild to severe, and affected individuals can go undetected for years because many of the clinical manifestations of TSC lack specificity. Once a diagnosis is made, TSC management strategies should be tailored to address the symptoms and risks most relevant to the age of the patient. Improved understanding of the genetic basis of TSC and of the central issue of mTOR overactivation has led to use of pharmacotherapies such as the mTOR inhibitors everolimus and sirolimus in the treatment of TSC disease. In Phase II and III studies, everolimus has demonstrated efficacy and safety in the treatment of both brain (subependymal giant cell astrocytoma) and renal (angiomyolipoma) manifestations associated with TSC. It is important to bear in mind that TSC is a lifelong condition, and for those diagnosed as children, a continuum of care will be needed as they transition from pediatric to adult health services. Clearly identifying the likely differences among diagnosis, monitoring, and management of pediatric and adult patients with TSC is an important step in enabling efficiencies to be maximized without compromising the care provided to patients. Keywords: mammalian target of rapamycin inhibitors, mTOR treatment, treatment strategies