New Constraints on the Melting Temperature and Phase Stability of Shocked Iron up to 270 GPa Probed by Ultrafast X-Ray Absorption Spectroscopy.

Studying the properties and phase diagram of iron at high-pressure and high-temperature conditions has relevant implications for Earth's inner structure and dynamics and the temperature of the inner core boundary (ICB) at 330 GPa. Also, a hexagonal-closed packed to body-centered cubic (bcc) phase transition has been predicted by many theoretical works but observed only in a few experiments. The recent coupling of high-power laser with advanced x-ray sources from synchrotrons allows for novel approaches to address these issues.

Development of MHz X-ray phase contrast imaging at the European XFEL.

We report on recent developments that enable megahertz hard X-ray phase contrast imaging (MHz XPCI) experiments at the Single Particles, Clusters, and Biomolecules and Serial Femtosecond Crystallography (SPB/SFX) instrument of the European XFEL facility (EuXFEL). We describe the technical implementation of the key components, including an MHz fast camera and a modular indirect X-ray microscope system based on fast scintillators coupled through a high-resolution optical microscope, which enable full-field X-ray microscopy with phase contrast of fast and irreversible phenomena. The image quality for MHz XPCI data showed significant improvement compared with a pilot demonstration of the technique using parallel beam illumination, which also allows access to up to 24 keV photon energies at the SPB/SFX instrument of the EuXFEL.

A pilot study of virtual Harm Reduction Talking Circles for American Indian and Alaska Native adults with alcohol use disorder.

Prior research suggests that culturally aligned, accessible and lower-barrier interventions are well-placed to align with the needs of American Indian and Alaska Native (AI/AN) people with alcohol use disorder (AUD). Taking into account community members' suggestions and the need for physical distancing during the COVID-19 pandemic, our team developed a protocol for virtual Harm Reduction Talking Circles (HaRTC) to incorporate these points. The aims of this 8-week, single-arm pilot were to initially document feasibility, acceptability, and outcomes associated with attendance at virtual HaRTC, which integrates the accessibility of virtual connection, a lower-barrier harm-reduction approach, and a culturally aligned intervention.

Thermoreflectance-based approach for surface temperature measurements of thin-film gold sensors.

A novel thermoreflectance-based diagnostic tool capable of visualizing spatial and temporal changes in surface temperature is presented. The method uses narrow spectral emission bands of blue [λ = 405 nm with 10 nm full-width-at-half-maximum (FWHM)] and green (λ = 532 nm with 10 nm FWHM) light to monitor the optical properties of gold and thin-film gold sensors, relating changes in reflectivity to temperature through a known calibration coefficient. The system is made robust to tilt and surface roughness variations through the simultaneous measurement of both probing channels with a single camera.

Measuring the principal Hugoniot of inertial-confinement-fusion-relevant TMPTA plastic foams.

Wetted-foam layers are of significant interest for inertial-confinement-fusion capsules, due to the control they provide over the convergence ratio of the implosion and the opportunity this affords to minimize hydrodynamic instability growth. However, the equation of state for fusion-relevant foams are not well characterized, and many simulations rely on modeling such foams as a homogeneous medium with the foam average density. To address this issue, an experiment was performed using the VULCAN Nd:glass laser at the Central Laser Facility.

Alcohol intoxication and sexual risk intentions: Exploring cultural factors among heavy drinking women.

Introduction: Sexually Transmitted Infections (STI) rates are the highest of the last 20 years, with people of color and women particularly affected. Ongoing research has identified risk factors (e.g.

Collapse dynamics of spherical cavities in a solid under shock loading.

Extraordinary states of highly localised pressure and temperature can be generated upon the collapse of impulsively driven cavities. Direct observation of this phenomenon in solids has proved challenging, but recent advances in high-speed synchrotron radiography now permit the study of highly transient, subsurface events in real time. We present a study on the shock-induced collapse of spherical cavities in a solid polymethyl methacrylate medium, driven to shock states between 0.

Perceived descriptive norms for alcohol use among tribal college students: Relation to self-reported alcohol use, consequences, and risk for alcohol use disorder.

This research addressed gaps in the literature by testing relationships between perceived descriptive alcohol use norms and individual's own alcohol use and consequences among tribal college and university (TCU) students. Survey data were collected from 3239 tribal college students in 22 TCUs across the United States in 2015 and 2016, of whom 3174 provided usable data on the variables of interest for the current manuscript. Results indicated students misperceived the descriptive norms for alcohol use at their TCU, on average estimating students at their college drank more frequently, more per occasion, and more total drinks per week relative to the observed averages on these outcomes.

Informed consent, shared-decision making and a reasonable patient's wishes based on a cross-sectional, national survey in the USA using a hypothetical scenario.

Objective: In approximately half the states in the USA, and more recently in the UK, informed consent is legally defined as what a reasonable patient would wish to know. Our objective was to discern the information needs of a hospitalised, 'reasonable patient' during the informed-consent process.

Design: We performed a cross-sectional study to develop a survey instrument and better define 'reasonable person' in relation to informed consent in a hypothetical scenario where an invasive procedure may be an option.

Ultra-high-speed indirect x-ray imaging system with versatile spatiotemporal sampling capabilities.

A new generation of cameras has made ultra-high-speed x-ray imaging at synchrotron light sources a reality, revealing never-before-seen details of sub-surface transient phenomena. We introduce a versatile indirect imaging system capable of capturing-for the first time-hundreds of sequential x-ray pulses in 16-bunch mode at the European Synchrotron Radiation Facility, recording at 5.68 Mfps over dozens of microseconds, with an effective exposure of 100 ps.

Ultrafast Imaging of Laser Driven Shock Waves using Betatron X-rays from a Laser Wakefield Accelerator.

Betatron radiation from laser wakefield accelerators is an ultrashort pulsed source of hard, synchrotron-like x-ray radiation. It emanates from a centimetre scale plasma accelerator producing GeV level electron beams. In recent years betatron radiation has been developed as a unique source capable of producing high resolution x-ray images in compact geometries.

Corrigendum: Probing the early stages of shock-induced chondritic meteorite formation at the mesoscale.

This corrects the article DOI: 10.1038/srep45206.

Probing the early stages of shock-induced chondritic meteorite formation at the mesoscale.

Chondritic meteorites are fragments of asteroids, the building blocks of planets, that retain a record of primordial processes. Important in their early evolution was impact-driven lithification, where a porous mixture of millimetre-scale chondrule inclusions and sub-micrometre dust was compacted into rock. In this Article, the shock compression of analogue precursor chondrite material was probed using state of the art dynamic X-ray radiography.

Monte-Carlo modelling to determine optimum filter choices for sub-microsecond optical pyrometry.

When designing a spectral-band pyrometer for use at high time resolutions (sub-μs), there is ambiguity regarding the optimum characteristics for a spectral filter(s). In particular, while prior work has discussed uncertainties in spectral-band pyrometry, there has been little discussion of the effects of noise which is an important consideration in time-resolved, high speed experiments. Using a Monte-Carlo process to simulate the effects of noise, a model of collection from a black body has been developed to give insights into the optimum choices for centre wavelength and passband width.

Sexual Assault Disclosure and Sexual Functioning: The Role of Trauma Symptomatology.

Introduction: Previous research has demonstrated that a history of adult sexual assault (ASA) is associated with negative outcomes, including trauma symptomatology and fear of sexual intimacy. Disclosing sexual assault might be protective against such negative outcomes.

Aim: To examine the indirect effect of trauma symptomatology on the association between disclosing ASA and current sexual functioning.

Depressive Symptoms, Acute Alcohol Intoxication, and Risk Rationale Effects on Men's Condom Use Resistance.

This study examined the role of depressive symptoms, acute intoxication, and risk rationale in men's use of condom use resistance (CUR) tactics in an experimental study. Participants included 313 heterosexual male, nonproblem drinkers, ages 21 to 30. Participants were randomized to one of four beverage conditions: no alcohol, placebo, low (.

Effects of parental monitoring on alcohol use in the US and Sweden: A brief report.

Objective: Adolescent alcohol use predicts a myriad of negative mental and physical health outcomes including fatality (Midanik, 2004). Research in parental influence on alcohol consumption finds parental monitoring (PM), or knowing where/whom your child is with, is associated with lower levels of alcohol use in adolescents (e.g.

Probing local and electronic structure in Warm Dense Matter: single pulse synchrotron x-ray absorption spectroscopy on shocked Fe.

Understanding Warm Dense Matter (WDM), the state of planetary interiors, is a new frontier in scientific research. There exists very little experimental data probing WDM states at the atomic level to test current models and those performed up to now are limited in quality. Here, we report a proof-of-principle experiment that makes microscopic investigations of materials under dynamic compression easily accessible to users and with data quality close to that achievable at ambient.

Evaluating scintillator performance in time-resolved hard X-ray studies at synchrotron light sources.

The short pulse duration, small effective source size and high flux of synchrotron radiation is ideally suited for probing a wide range of transient deformation processes in materials under extreme conditions. In this paper, the challenges of high-resolution time-resolved indirect X-ray detection are reviewed in the context of dynamic synchrotron experiments. In particular, the discussion is targeted at two-dimensional integrating detector methods, such as those focused on dynamic radiography and diffraction experiments.

A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation.

The dynamic fracture of a body is a late-stage phenomenon typically studied under simplified conditions, in which a sample is deformed under uniform stress and strain rate. This can be produced by evenly loading the inner surface of a cylinder. Due to the axial symmetry, as the cylinder expands the wall is placed into a tensile hoop stress that is uniform around the circumference.

Attenuation of the dynamic yield point of shocked aluminum using elastodynamic simulations of dislocation dynamics.

When a metal is subjected to extremely rapid compression, a shock wave is launched that generates dislocations as it propagates. The shock wave evolves into a characteristic two-wave structure, with an elastic wave preceding a plastic front. It has been known for more than six decades that the amplitude of the elastic wave decays the farther it travels into the metal: this is known as "the decay of the elastic precursor.

X-ray imaging of subsurface dynamics in high-Z materials at the Diamond Light Source.

In this paper, we describe a new approach enabling study of subsurface dynamics in high-Z materials using the unique combination of high-energy synchrotron X-rays, a hybrid bunch structure, and a new dynamic loading platform. We detail the design and operation of the purpose-built, portable small bore gas-gun, which was installed on the I12 high-energy beamline at the Diamond Light Source and used to drive compression waves into solid and porous metal targets. Using a hybrid bunch structure and broadband X-ray pulses of up to 300 keV, radiographic snapshots were captured during various dynamic deformation processes in cm-scale specimens, thereby contributing to a more complete understanding of the evolution of mesoscale damage.

Alcohol intoxication and condom use self-efficacy effects on women's condom use intentions.

Although research has consistently demonstrated that condom use self-efficacy significantly predicts condom use, there has been little investigation of whether acute alcohol intoxication moderates this relationship. Because alcohol intoxication is often associated with increased sexual risk taking, further examination of such moderating effects is warranted. Using a community sample of young heterosexual women (n=436) with a history of heavy episodic drinking, this alcohol administration experiment examined the effects of intoxication and condom use self-efficacy on women's condom negotiation and future condom use intentions.