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The high-pressure behavior of germanates is of interest as these compounds serve as analogs for silicates of the deep Earth. Current theoretical and experimental studies of iron germanate, FeGeO3, are limited. Here, we have examined the behavior of FeGeO3 to 127 GPa using the laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction. Upon compression at room temperature, the ambient-pressure clinopyroxene phase transforms to a disordered triclinic phase [FeGeO3 (II)] at ~ 18 GPa in agreement with earlier studies. An additional phase transition to FeGeO3 (III) occurs above 54 GPa at room temperature. Laser-heating experiments (~ 1200–2200 K) were conducted at three pressures (33, 54, and 123 GPa) chosen to cover the stability regions of different GeO2 polymorphs. In all cases, we observe that FeGeO3 dissociates into GeO2 + FeO at high pressure and temperature conditions. Neither the perovskite nor the post-perovskite phase was observed up to 127 GPa at ambient or high temperatures. The results are consistent with the behavior of FeSiO3, which also dissociates into a mixture of the oxides (FeO + SiO2) at least up to 149 GPa.

Herein, frequency conversion to the third‐ and fourth‐order harmonics are demonstrated in ultracompact cascaded periodically poled thin‐film lithium niobate (LN) waveguides on silicon substrates. Pumped at 1550 nm wavelength, the tightly confined waveguides produce strong third‐ (523 nm) and fourth‐harmonic (386 nm) signals. Actively monitoring the periodic poling process on the LN devices renders these efficient frequency conversions. Measurements with a femtosecond pulsed laser source result in comparable power levels across the generated harmonics. A model that simulates harmonic generation from the pulsed source is presented and discussed. The model's results are in general agreement with the experimentally observed processes.

This interpretive research study explores U.S. adults' lived experiences during the beginning months of the COVID-19 global pandemic. Participants ( N = 44), recruited from a convenience sample of U.S. adults, engaged in in-depth semi-structured interviews or focus groups. Through an iterative analysis of participants' experiences and the theoretical model of communal coping (TMCC), the authors identified three convergent stressors (i.e., isolation, uncertainty, conflict ) and several coping strategies related to participants' stressor appraisal (i.e., individual or joint) and action orientation (i.e., individual or joint). Based on these findings, this study offers the novel theoretical concept of Discursive coping and proposes a model for how this perspective might be integrated with current theorizing about individual and communal coping. Implications for communal coping and discursive theory are discussed as well as practical recommendations for public health messaging.

There needs to be serious transformation of evidence-based interventions (EBIs) into real-world solutions; otherwise, EBIs will never achieve the intended public health impact. In a randomized trial, we reported effects of a redesigned anxiety program. Herein, we described the redesign process that led to the program. Survey data revealed provider preferences for school mental health anxiety services. Focus groups and prototype feedback sessions revealed service barriers to uptake, implementation, and sustainability along with corresponding enabling strategies. Prototype feedback sessions also focused on refinement and fine-tuning of the redesign. In the end, traditional EBI strategies were transformed and packaged into six lessons, lasting 20-30 minutes each, and amenable to delivery in small-group format. The redesign achieved the intended purpose of retaining elements from cognitive and behavior therapy and social skills training for the target population of the intervention (e.g., 3rd to 5th graders with heterogeneous anxiety problems - identified and referred). The streamlined EBI is accessible from PBS LearningMedia™ - a service that hosts public, research-based, and school-ready materials., Competing Interests: Conflict of Interest The authors declare that they have no conflict of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

There has been considerable recent interest in the high-pressure behavior of silicon carbide, a potential major constituent of carbon-rich exoplanets. In this work, the atomic-level structure of SiC was determined through in situ X-ray diffraction under laser-driven ramp compression up to 1.5 TPa; stresses more than seven times greater than previous static and shock data. Here we show that the B1-type structure persists over this stress range and we have constrained its equation of state (EOS). Using this data we have determined the first experimentally based mass-radius curves for a hypothetical pure SiC planet. Interior structure models are constructed for planets consisting of a SiC-rich mantle and iron-rich core. Carbide planets are found to be ~10% less dense than corresponding terrestrial planets., (© 2022. The Author(s).)

Immunoassay techniques are commonly used for urine drug screening in forensic and clinical toxicology laboratories. While these techniques are excellent for the nonspecific detection of a wide variety of drug classes, their very nature renders them vulnerable to false negatives and false positives.The New York State Police Forensic Toxicology Laboratory investigated a trend of false-positive fentanyl urine drug screens and determined that urine methamphetamine levels greater than 40 μg/mL can cause a false-positive urine fentanyl screening result using the Neogen enzyme-linked immunosorbent assay kit at a 1 ng/mL fentanyl decision point., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Mg 2 GeO 4 is important as an analog for the ultrahigh-pressure behavior of Mg 2 SiO 4 , a major component of planetary interiors. In this study, we have investigated magnesium germanate to 275 GPa and over 2,000 K using a laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction and density functional theory (DFT) computations. The experimental results are consistent with the formation of a phase with disordered Mg and Ge, in which germanium adopts eightfold coordination with oxygen: the cubic, Th 3 P 4 -type structure. DFT computations suggest partial Mg-Ge order, resulting in a tetragonal [Formula: see text] structure indistinguishable from [Formula: see text] Th 3 P 4 in our experiments. If applicable to silicates, the formation of this highly coordinated and intrinsically disordered phase may have important implications for the interior mineralogy of large, rocky extrasolar planets., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)

This study provides insight into lived experiences of the COVID-19 pandemic in the United States. Participant metaphors of the pandemic were collected by conducting in-depth semi-structured interviews ( N = 44). Participants were asked to compare the pandemic with an animal and with a color, and to provide contextual sensemaking about their metaphors. A metaphor analysis revealed four convergent mental models of participants' pandemic experiences (i.e., uncertainty, danger, grotesque, and misery) as well as four primary emotions associated with those mental models (i.e., grief, disgust, anger, and fear). Through metaphor, participants were able to articulate deeply felt, implicit emotions about their pandemic experiences that were otherwise obscured and undiscussable. Theoretical and practical implications of these collective mental models and associated collective emotions related to the unprecedented collective trauma of the COVID-19 pandemic are discussed.

Because of its far-reaching applications in geophysics and materials science, quartz has been one of the most extensively examined materials under dynamic compression. Despite 50 years of active research, questions remain concerning the structure and transformation of SiO 2 under shock compression. Continuum gas-gun studies have established that under shock loading quartz transforms through an assumed mixed-phase region to a dense high-pressure phase. While it has often been assumed that this high-pressure phase corresponds to the stishovite structure observed in static experiments, there have been no crystal structure data confirming this. In this study, we use gas-gun shock compression coupled with in situ synchrotron x-ray diffraction to interrogate the crystal structure of shock-compressed α-quartz up to 65 GPa. Our results reveal that α-quartz undergoes a phase transformation to a disordered metastable phase as opposed to crystalline stishovite or an amorphous structure, challenging long-standing assumptions about the dynamic response of this fundamental material., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

SiO 2 is one of the most fundamental constituents in planetary bodies, being an essential building block of major mineral phases in the crust and mantle of terrestrial planets (1-10 M E ). Silica at depths greater than 300 km may be present in the form of the rutile-type, high pressure polymorph stishovite (P4 2 /mnm) and its thermodynamic stability is of great interest for understanding the seismic and dynamic structure of planetary interiors. Previous studies on stishovite via static and dynamic (shock) compression techniques are contradictory and the observed differences in the lattice-level response is still not clearly understood. Here, laser-induced shock compression experiments at the LCLS- and SACLA XFEL light-sources elucidate the high-pressure behavior of stishovite on the lattice-level under in situ conditions on the Hugoniot to pressures above 300 GPa. We find stishovite is still (meta-)stable at these conditions, and does not undergo any phase transitions. This contradicts static experiments showing structural transformations to the CaCl 2 , α-PbO 2 and pyrite-type structures. However, rate-limited kinetic hindrance may explain our observations. These results are important to our understanding into the validity of EOS data from nanosecond experiments for geophysical applications.

In this essay, the author makes the case that a defining moment for the communication discipline is to encourage increased uptake of embodied conversation. The essay shares illustrative examples and reviews research on issues such as loneliness, anxiety, social comparison, empathy, compassion, social media, electronic medical records, facial mimicry and more. It then describes various strategies that the communication discipline might employ in their research and pedagogy that motivate the practice of embodied conversation. The essay concludes with an invitation to communication scholars from a wide range of focus areas and generations to join in (re)creating "conversation as cool."

We combined laser shock compression with in situ x-ray diffraction to probe the crystallographic state of gold (Au) on its principal shock Hugoniot. Au has long been recognized as an important calibration standard in diamond anvil cell experiments due to the stability of its face-centered cubic (fcc) structure to extremely high pressures (P >600  GPa at 300 K). This is in contrast to density functional theory and first principles calculations of the high-pressure phases of Au that predict a variety of fcc-like structures with different stacking arrangements at intermediate pressures. In this Letter, we probe high-pressure and high-temperature conditions on the shock Hugoniot and observe fcc Au at 169 GPa and the first evidence of body-centered cubic (bcc) Au at 223 GPa. Upon further compression, the bcc phase is observed in coexistence with liquid scattering as the Hugoniot crosses the Au melt curve before 322 GPa. The results suggest a triple point on the Au phase diagram that lies very close to the principal shock Hugoniot near ∼220  GPa.

Change is a constant feature of organizing and one that requires resilience, or the ability to effectively face challenges. Although research demonstrates important findings about resilience during chaotic change like crises, less is known about resilience in mundane situations like planned change. This study explores team-driven planned organizational change, offering insights about how team members metaphorically frame change how their framing fluctuates over time relative to perceptions of team success. Our three theoretical contributions extend theory about metaphors and organizational change, showing how negative framings of change are endemic to teams, regardless of perceived success; generate knowledge about resilience in organizing by showing how metaphors both build and undermine resilience; and extend applied theory about stakeholder participation in bureaucratic organizations.

Because of its widespread applications in materials science and geophysics, SiO_{2} has been extensively examined under shock compression. Both quartz and fused silica transform through a so-called "mixed-phase region" to a dense, low compressibility high-pressure phase. For decades, the nature of this phase has been a subject of debate. Proposed structures include crystalline stishovite, another high-pressure crystalline phase, or a dense amorphous phase. Here we use plate-impact experiments and pulsed synchrotron x-ray diffraction to examine the structure of fused silica shock compressed to 63 GPa. In contrast to recent laser-driven compression experiments, we find that fused silica adopts a dense amorphous structure at 34 GPa and below. When compressed above 34 GPa, fused silica transforms to untextured polycrystalline stishovite. Our results can explain previously ambiguous features of the shock-compression behavior of fused silica and are consistent with recent molecular dynamics simulations. Stishovite grain sizes are estimated to be ∼5-30  nm for compression over a few hundred nanosecond time scale.

Ab initio molecular dynamics, supported by inelastic neutron scattering and nuclear resonant inelastic x-ray scattering, showed an anomalous thermal softening of the M_{5}^{-} phonon mode in B2-ordered FeTi that could not be explained by phonon-phonon interactions or electron-phonon interactions calculated at low temperatures. A computational investigation showed that the Fermi surface undergoes a novel thermally driven electronic topological transition, in which new features of the Fermi surface arise at elevated temperatures. The thermally induced electronic topological transition causes an increased electronic screening for the atom displacements in the M_{5}^{-} phonon mode and an adiabatic electron-phonon interaction with an unusual temperature dependence.

Background: Mineralocorticoid receptor antagonists (MRAs) are the most underutilized pharmacotherapy for heart failure. Minimal data are available on the barriers to MRA adoption from the perspective of prescribing clinicians., Methods and Results: A mixed-methods study consisting of a survey (n=50), focus groups (n=39), interviews (n=6) with clinicians at a single US Department of Veterans Affairs medical center served to ascertain barriers to optimal use of MRAs. Participants were drawn from 6 groups: cardiology providers, cardiology fellows, hospitalists, clinical pharmacists, internal medicine residents, and primary care providers. Qualitative data were iteratively coded with qualitative data analysis software. The survey response rate was 17.3%. Overall, 51% of survey respondents were unfamiliar with eplerenone, and 6% were unfamiliar with spironolactone. In addition, 30% of respondents reported that they would order a laboratory test >2 weeks after a new MRA prescription, although that is beyond the guideline recommendation. Most providers correctly identified New York Heart Association class 3 and 4 patients as MRA eligible, but only 42% identified class 2 patients as MRA eligible. Through analysis of focus groups, we identified 8 barriers to MRA use in 3 categories: patient-based barriers (concerns about polypharmacy and comorbidities, adverse effects, perceived patient nonadherence), provider-based barriers (unclear roles and responsibilities, coordination and transitions of care, lack of experience or familiarity with MRAs), and system-based barriers (system overload and provider time constraints, lack of systematic follow-up procedures)., Conclusions: Eight primary barriers to MRA adoption at the provider, patient, and health system levels were identified from the prescriber perspective. These barriers can inform the creation of multilevel interventions that will be required to close the gap in MRA adoption., (© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

In this study, we examined metaphors invoked by people recovering from opioid dependence as they described the challenges and successes of using medication-assisted treatment. Metaphors provide linguistic tools for expressing issues that are confusing, complex, hidden, and difficult to state analytically or literally. Using data from eight focus groups with 68 participants representing four ethnic minority groups, we conducted a grounded analysis to show how recovering substance users communicatively constructed addiction and recovery. The primary medication, methadone, was framed as "liquid handcuffs" that allowed those in recovery to quit "hustling," get "straight," and find "money in their pockets." Nonetheless, methadone also served as a "crutch," leaving them still feeling like "users" with "habits" who "came up dirty" to friends and family. In this analysis, we tease out implications of these metaphors, and how they shed light on sensemaking, agency, and related racial- and class-based structural challenges in substance abuse recovery.

Cubic scandium trifluoride (ScF3) has a large negative thermal expansion over a wide range of temperatures. Inelastic neutron scattering experiments were performed to study the temperature dependence of the lattice dynamics of ScF3 from 7 to 750 K. The measured phonon densities of states show a large anharmonic contribution with a thermal stiffening of modes around 25 meV. Phonon calculations with first-principles methods identified the individual modes in the densities of states, and frozen phonon calculations showed that some of the modes with motions of F atoms transverse to their bond direction behave as quantum quartic oscillators. The quartic potential originates from harmonic interatomic forces in the DO9 structure of ScF3, and accounts for phonon stiffening with the temperature and a significant part of the negative thermal expansion.

Ischemia is a potent modulator of gene expression. Differential expression of transcription factors after focal ischemia may reflect the potential for neuronal recovery in peri-ischemic regions. Previously, we demonstrated that hypothermia reduces the volume of damage in a model of neonatal focal ischemia. In the present study, immunocytochemistry was used to assess the temporal and spatial profiles of the transcription factors Fos and pCREB under normal and hypothermic conditions in this neonatal model of focal ischemia. At 7 days of age, rat pups underwent a permanent middle cerebral artery occlusion (MCAo) coupled with a temporary 1-h occlusion of the common carotid artery (CCAo). They were maintained at 37 degrees C throughout ischemia and reperfusion (Normothermic), or given 1 h of hypothermic conditions (28 degrees C) either during the occlusion (Intraischemic Hypothermia) or during the second hour of reperfusion (postischemic hypothermia). In normothermic pups, Fos immunoreactivity peaked at early time points (4-8 h post-ischemia) in a narrow band in peri-ischemic regions. By later stages of reperfusion (12-24 h), there was a more widespread induction in peri-ischemic regions including the ipsilateral cortex. In contrast with Fos, the constitutive transcription factor pCREB was reduced in core regions at all time points examined. Both the c-fos induction in peri-ischemic regions and the reduction of pCREB in the core were attenuated by intraischemic hypothermia. Postischemic hypothermia altered the distribution of Fos immunoreactivity without significantly changing the number of Fos- and pCREB-immunoreactive cells compared to normothermic rats. Both intra- and postischemic hypothermia reduced the number of caspase-immunoreactive cells. Thus, focal ischemia in the P7 rat produces different distributions of Fos and pCREB than what has been observed in adult rats subjected to focal ischemia, and expression of these transcription factors can be altered by hypothermia.

Hypothermia provides neuroprotection in virtually all animal models of ischemia, including adult stroke models and the neonatal hypoxic-ischemic (HI) model. In these studies, brief periods of hypothermia are examined in a neonatal model employing transient focal ischemia in a 7-day-old rat pup. Pups underwent permanent middle cerebral artery (MCA) occlusion coupled with a temporary (1 h) occlusion of the ipsilateral common carotid artery (CCA). This study included five treatment groups: (1) normothermic (Normo)-brain temperature was maintained at 37 degrees C; (2) intraischemic hypothermia (IntraH)-28 degrees C during the 1-h ischemic period only; (3) postischemic hypothermia (PostH)-28 degrees C for the second hour of reperfusion only; (4) late-onset postischemic hypothermia (LPostH) cooled to 28 degrees C for the fifth and sixth hours of reperfusion only; and (5) Shams. After various times (3 days-6 weeks), the lesion was assessed using 2,3,5-triphenyltetrazolium chloride (TTC) or hematoxylin and eosin (H&E) stains. Intraischemic hypothermia resulted in significant protection in terms of survival, lesion size, and histology. Postischemic hypothermia was not effective in reducing lesion size early after ischemia, but significantly reduced the eventual long-term damage (2-6 weeks). Late-onset postischemic hypothermia did not reduce infarct volume. Therefore, both intraischemic and postischemic hypothermia provided neuroprotection in the neonatal rat, but with different effects on the degenerative time course. While there were no observable differences in simple behaviors or growth, all hypothermic conditions significantly reduced mortality rates. While the protection resulting from intraischemic hypothermia is similar to what is observed in other models, the degree of long-term ischemic protection observed after 1 h of postischemic hypothermia was remarkable and distinct from what has been observed in other adult or neonatal models.