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Plasticity is often controlled by dislocation motion, which was first measured for low pressure, low strain rate conditions decades ago. However, many applications require knowledge of dislocation motion at high stress conditions where the data are sparse, and come from indirect measurements dominated by the effect of dislocation density rather than velocity. Here we make predictions based on atomistic simulations that form the basis for a new approach to measure dislocation velocities directly at extreme conditions using three steps: create prismatic dislocation loops in a near-surface region using nanoindentation, drive the dislocations with a shockwave, and use electron microscopy to determine how far the dislocations moved and thus their velocity at extreme stress and strain rate conditions. We report on atomistic simulations of tantalum that make detailed predictions of dislocation flow, and find that the approach is feasible and can uncover an exciting range of phenomena, such as transonic dislocations and a novel form of loop stretching. The simulated configuration enables a new class of experiments to probe average dislocation velocity at very high applied shear stress. more...

Large laser facilities have recently enabled material characterization at the pressures of Earth and Super-Earth cores. However, the temperature of the compressed materials has been largely unknown, or solely relied on models and simulations, due to lack of diagnostics under these challenging conditions. Here, we report on temperature, density, pressure, and local structure of copper determined from extended x-ray absorption fine structure and velocimetry up to 1 Terapascal. These results nearly double the highest pressure at which extended x-ray absorption fine structure has been reported in any material. In this work, the copper temperature is unexpectedly found to be much higher than predicted when adjacent to diamond layer(s), demonstrating the important influence of the sample environment on the thermal state of materials; this effect may introduce additional temperature uncertainties in some previous experiments using diamond and provides new guidance for future experimental design., (© 2023. The Author(s).) more...

Background: Although there is increasing interest in reporting results of environmental research efforts back to participants, evidence-based tools have not yet been applied to developed materials to ensure their accessibility in terms of literacy, numeracy, and data visualization demand. Additionally, there is not yet guidance as to how to formally assess the created materials to assure a match with the intended audience., Methods: Relying on formative qualitative research with participants of an indoor air quality study in Dorchester, Massachusetts, we identified means of enhancing accessibility of indoor air quality data report-back materials for participants. Participants (n = 20) engaged in semi-structured interviews in which they described challenges they encountered with scientific and medical materials and outlined written and verbal communication techniques that would help facilitate engagement with and accessibility of environmental health report-back materials. We coupled these insights from participants with best practice guidelines for written materials by operationalizing health literacy tools to produce accessible audience-informed data report-back materials., Results: The resulting data report-back materials had a 7th -grade reading level, and between a 4th -8th grade level of overall document complexity. The numeracy skills required to engage with the material were of the lowest demand, and we incorporated best practices for risk communication and facilitating understanding and actionability of the materials. Use of a rigorous assessment tool provides evidence of accessibility and appropriateness of the material for the audience., Conclusions: We outline a process for developing and evaluating environmental health data reports that are tailored to inspire risk-reduction actions, and are demonstrably accessible in terms of their literacy, numeracy, and data visualization demand. Adapting health literacy tools to create and evaluate environmental data report-back materials is a novel and evidence-based means of ensuring their accessibility., (© 2022. The Author(s).) more...

This study is based on in-depth semi-structured interviews with the participants of an indoor air quality monitoring study. The purpose of the interviews was to capture participants' perceptions of indoor air quality and engage them in a discussion of those factors that influenced their behavior. Interview study participants ( n = 20) noted the importance of family health concerns and their own sensory awareness of possible contaminants. They discussed their level of personal control over their home environment as well as their access to needed resources. This study is based on grounded theory and applies interpretivist epistemological methods. Study findings offer insights into how people perceive their home environment and what influences their decision making and action. Analyses indicate that perceived agency, risk perception, access to resources, and information all influenced participants' sense of ability to take action as well as their interest in taking action. These insights serve to challenge some of the current work in environmental health literacy which tends to focus on and measure an individual's knowledge or skills. Our analysis suggests that consideration be given to a number of factors that include perceived agency, access to resources, and the quality of information provided. more...

Successful dissemination of scientific knowledge relies on the ability of the writer, speaker, and designer to provide information and data that is both available and accessible to the audience for whom it is intended. Scientific rigor, uniformly applied to the development of medicines, products, and devices must be applied, as well, to communications-spoken, written, posted, or displayed. Rigorous development and design protocols call for formative research data gathering, careful pilot testing with members of the intended audience, needed revisions, and rigorous assessments. Guidelines and tools developed for health literacy applications can be adopted and adapted for environmental health research and educational efforts in the design of questionnaires, instructions, education and report back materials, as well as for public discourse. more...

Carbon is the fourth-most prevalent element in the Universe and essential for all known life. In the elemental form it is found in multiple allotropes, including graphite, diamond and fullerenes, and it has long been predicted that even more structures can exist at pressures greater than those at Earth's core 1-3 . Several phases have been predicted to exist in the multi-terapascal regime, which is important for accurate modelling of the interiors of carbon-rich exoplanets 4,5 . By compressing solid carbon to 2 terapascals (20 million atmospheres; more than five times the pressure at Earth's core) using ramp-shaped laser pulses and simultaneously measuring nanosecond-duration time-resolved X-ray diffraction, we found that solid carbon retains the diamond structure far beyond its regime of predicted stability. The results confirm predictions that the strength of the tetrahedral molecular orbital bonds in diamond persists under enormous pressure, resulting in large energy barriers that hinder conversion to more-stable high-pressure allotropes 1,2 , just as graphite formation from metastable diamond is kinetically hindered at atmospheric pressure. This work nearly doubles the highest pressure at which X-ray diffraction has been recorded on any material. more...

Laser compression has long been used as a method to study solids at high pressure. This is commonly achieved by sandwiching a sample between two diamond anvils and using a ramped laser pulse to slowly compress the sample, while keeping it cool enough to stay below the melt curve. We demonstrate a different approach, using a multilayer 'ring-up' target whereby laser-ablation pressure compresses Pb up to 150 GPa while keeping it solid, over two times as high in pressure than where it would shock melt on the Hugoniot. We find that the efficiency of this approach compares favourably with the commonly used diamond sandwich technique and could be important for new facilities located at XFELs and synchrotrons which often have higher repetition rate, lower energy lasers which limits the achievable pressures that can be reached. more...

The theory of grain boundary (the interface between crystallites, GB) structure has a long history 1 and the concept of GBs undergoing phase transformations was proposed 50 years ago 2,3 . The underlying assumption was that multiple stable and metastable states exist for different GB orientations 4-6 . The terminology 'complexion' was recently proposed to distinguish between interfacial states that differ in any equilibrium thermodynamic property 7 . Different types of complexion and transitions between complexions have been characterized, mostly in binary or multicomponent systems 8-19 . Simulations have provided insight into the phase behaviour of interfaces and shown that GB transitions can occur in many material systems 20-24 . However, the direct experimental observation and transformation kinetics of GBs in an elemental metal have remained elusive. Here we demonstrate atomic-scale GB phase coexistence and transformations at symmetric and asymmetric [Formula: see text] tilt GBs in elemental copper. Atomic-resolution imaging reveals the coexistence of two different structures at Σ19b GBs (where Σ19 is the density of coincident sites and b is a GB variant), in agreement with evolutionary GB structure search and clustering analysis 21,25,26 . We also use finite-temperature molecular dynamics simulations to explore the coexistence and transformation kinetics of these GB phases. Our results demonstrate how GB phases can be kinetically trapped, enabling atomic-scale room-temperature observations. Our work paves the way for atomic-scale in situ studies of metallic GB phase transformations, which were previously detected only indirectly 9,15,27-29 , through their influence on abnormal grain growth, non-Arrhenius-type diffusion or liquid metal embrittlement. more...

Following the March 2011 accident at Fukushima Daiichi Nuclear Power Plant, many residents of Fukushima have faced anxieties about the health impacts of radiation exposure. Considering that source of information may influence resident anxiety, this study aimed to elucidate the correlation between the two. In addition, a health literacy query was included to examine a possible relationship between anxiety and health literacy skills. A mail survey was conducted in August 2016 among 2000 residents of Fukushima Prefecture aged 20 to 79 years. Survey items included questions about current health anxieties caused by radiation, trusted sources of information about radiation, and media used to obtain information on radiation. The survey valid response rate was 43.4%. Results of multiple linear regression analysis revealed that anxiety was significantly higher for the groups indicating "trust in citizen groups" and "use of internet sites." Anxiety was significantly lower for the groups indicating "trust in government ministries," "trust in local government," and "use of local broadcast television." Also anxiety was significantly lower for groups with higher health literacy. It was found that the significant relationship to anxiety varies depending on the sources of trust and media used. There is a possibility that this was caused by the difference between the contents of each information and media reports. In preparation for any future nuclear accident, government may consider action to improve the media literacy of residents. In addition, improving health literacy of both the recipient and the sender of information can improve access to information and thereby safeguard the health and well-being of the public., Competing Interests: The authors have declared that no competing interests exist. more...

The study of grain boundary phase transitions is an emerging field until recently dominated by experiments. The major bottleneck in the exploration of this phenomenon with atomistic modeling has been the lack of a robust computational tool that can predict interface structure. Here we develop a computational tool based on evolutionary algorithms that performs efficient grand-canonical grain boundary structure search and we design a clustering analysis that automatically identifies different grain boundary phases. Its application to a model system of symmetric tilt boundaries in Cu uncovers an unexpected rich polymorphism in the grain boundary structures. We find new ground and metastable states by exploring structures with different atomic densities. Our results demonstrate that the grain boundaries within the entire misorientation range have multiple phases and exhibit structural transitions, suggesting that phase behavior of interfaces is likely a general phenomenon. more...

Public health nurses (PHNs) are community residents' access points to health information and services in Japan. After the Fukushima nuclear accident, they were challenged to communicate radiation-related health information to best meet community needs. We previously developed and evaluated the outcome of a single-site health literacy training program to augment PHNs' ability to improve community residents' access to written health information. This paper presents an evaluation of an identical training program using data combined from multiple sites, and further included proximal and distal evaluations to document the impact of health literacy training in a post-disaster setting. A total of 64 participants, primarily experienced PHNs, attended one of three multi-session health literacy workshops conducted in multiple sites across Fukushima. Quantitative and qualitative data on PHNs' training satisfaction, self-evaluation of achievements regarding training goals, and application of learned skills were collected and analyzed. Each workshop consisted of two 2-hour sessions introducing health literacy and assessment tools and developing skills to improve written materials, followed by a one-month follow-up assessment on PHNs' application of the gained skills in the field. Post-training evaluations on the appropriateness and usefulness of the workshop were highly positive. At the end of the one-month follow-up, 45% of participants had gained confidence in assessing and revising written materials and had applied the skills they had gained to develop and communicate health information in various settings and modes. This increase in confidence was associated with further application of the learned skills at the municipal level. However, participants reported difficulties in explaining risks, and the need to learn more about plain language to be able to paraphrase professional terms. This paper highlighs the positive outcomes of health literacy training among PHNs. Practical strategies to reinforce their skills to use plain language and communicate the epidemiological concept of risk are also recommended. more...

Self-report of musculoskeletal conditions is often used to estimate population prevalence and to determine disease burden and influence policy. However, self-report of certain musculoskeletal conditions is frequently inaccurate, suggesting inadequate communication to the patient of their diagnosis. The aim of this study is to determine the association between functional health literacy (FHL) and self-reported musculoskeletal conditions in a representative population survey. FHL was measured using Newest Vital Sign in 2824 randomly selected adults. Participants also self-reported medically diagnosed arthritis, gout, and osteoporosis. Multiple logistic regression was adjusted for age and sex. The prevalence of self-reported arthritis, gout, and osteoporosis was 25.2%, 4.9%, and 5.6%, respectively. The prevalence of those at risk for inadequate FHL was 24.0% and high likelihood of inadequate FHL was 21.0%. However, over 50% of respondents with arthritis or gout had at risk/inadequate FHL, increasing to 70% of those self-reporting osteoporosis. After adjustment for age and sex, respondents in the arthritis subgroup of "don't know" and self-reported osteoporosis were significantly more likely to have inadequate FHL than the general population. This study indicates a substantial burden of low health literacy amongst people with musculoskeletal disease. This has implications for provider-patient communication, individual healthcare, population estimates of musculoskeletal disease, and impact of public health messages. more...

Objectives: We conducted health literacy environmental scans in 26 Maryland community-based dental clinics to identify institutional characteristics and provider practices that affect dental services access and dental caries education., Methods: In 2011-2012 we assessed user friendliness of the clinics including accessibility, signage, facility navigation, educational materials, and patient forms. We interviewed patients and surveyed dental providers about their knowledge and use of communication techniques., Results: Of 32 clinics, 26 participated. Implementation of the health literacy environmental scan tools was acceptable to the dental directors and provided clinic directors with information to enhance care and outreach. We found considerable variation among clinic facilities, operations, and content of educational materials. There was less variation in types of insurance accepted, no-show rates, methods of communicating with patients, and electronic health records use. Providers who had taken a communication skills course were more likely than those who had not to use recommended communication techniques., Conclusions: Our findings provide insight into the use of health literacy environmental scan tools to identify clinic and provider characteristics and practices that can be used to make dental environments more user friendly and health literate. more...

The recent discovery of more than a thousand planets outside our Solar System, together with the significant push to achieve inertially confined fusion in the laboratory, has prompted a renewed interest in how dense matter behaves at millions to billions of atmospheres of pressure. The theoretical description of such electron-degenerate matter has matured since the early quantum statistical model of Thomas and Fermi, and now suggests that new complexities can emerge at pressures where core electrons (not only valence electrons) influence the structure and bonding of matter. Recent developments in shock-free dynamic (ramp) compression now allow laboratory access to this dense matter regime. Here we describe ramp-compression measurements for diamond, achieving 3.7-fold compression at a peak pressure of 5 terapascals (equivalent to 50 million atmospheres). These equation-of-state data can now be compared to first-principles density functional calculations and theories long used to describe matter present in the interiors of giant planets, in stars, and in inertial-confinement fusion experiments. Our data also provide new constraints on mass-radius relationships for carbon-rich planets. more...

Health literacy comprises not only an individual's ability to gain access to, understand and use health information, but also health care providers' ability to make health information accessible and usable. The Fukushima nuclear accident has posed challenges related to the communication of radiation-related health information. Public health nurses are gatekeepers of community health in Japan, and have primary responsibility for communicating this complex information about science and risk to lay members of the community. A health literacy training program was designed to augment communication skills of participating nurses with two primary goals: changing communication practices and norms among public health nurses, and improving access to information for community residents. Training content incorporated an overview of health literacy skills (including numeracy), processes for assessing written materials and visual displays, as well as guidelines for text improvement. The workshop was spread across two days with two-hour sessions each day. A proximal post-training evaluation survey was conducted, followed by a more distal one-month follow-up evaluation to assess the application of learned skills in practice. Twenty-six nurses in Fukushima City attended the first trial. Post-training evaluations were highly positive, with agreement from 85-100% of participants on the appropriateness and usefulness of the workshop. During a one-month follow-up, the nurses reported applying new knowledge and skills to develop written materials. However, they faced difficulties sharing their new skills with colleagues and challenges changing work norms. Participants also encountered difficulties using graphics and explaining risks in practice. This paper highlights the importance of providing health literacy training opportunities for professionals to strengthen health system's ability to accessible information and services. This program also serves as important reference for future disaster management efforts. more...

Background: Local public health nurses (PHNs) have been recognized as the main health service providers in communities in Japan. The Fukushima nuclear disaster in 2011 has, however, created a major challenge for them in responding to mothers' concerns. This was in part due to difficulties in assessing, understanding and communicating health risks on low-dose radiation exposure. In order to guide the development of risk communication plans, this study sought to investigate mothers' primary concerns and possible solutions perceived by a core healthcare profession like the PHNs., Methods: A total of 150 records from parenting counseling sessions conducted between PHNs and mothers who have attended mandatory 18-month health checkups for their children at the Fukushima City Health and Welfare Center in 2010, 2011 (year of disaster) and 2012 were examined. Discussion notes of three peer discussions among PHNs organized in response to the nuclear disaster in 2012 and 2013 were also analyzed. All transcribed data were first subjected to text mining to list the words according to their frequencies and inter-relationships. The Steps Coding and Theorization method was then undertaken as a framework for qualitative analysis., Results: PHNs noted mothers to have considerable needs for information on radiation risks as they impact on decisions related to relocations, concerns for child safety, and experiences with interpersonal conflicts within the family owing to differing risk perceptions. PHNs identified themselves as the information channels in the community, recommended the building of their risk communication capacities to support residents in making well-informed decisions, and advocated for self-measurement of radiation levels to increase residents' sense of control. PHNs also suggested a more standardized form of information dissemination and an expansion of community-based counseling services., Conclusions: Inadequate risk communication on radiation in the Fukushima nuclear incident has resulted in multiple repercussions for mothers in the community. Empowerment of local residents to assume more active roles in the understanding of their environment, increasing PHNs' capacity in communication, and an expansion of health services such as counseling will together better address risk communication challenges in post-disaster recovery efforts. more...

Objective: To determine the factors associated with cancer screening adherence among Native Americans living in California., Participants: 2,266 Native Americans identified from the California Health Interview Surveys during 2001, 2003, and 2005 eligible for cervical, breast, or colorectal cancer screening., Methods: We fit multivariable logistic regression models to identify demographic and healthcare access predictors of adherence to cancer screening., Results: The presence of a recent physician visit was significantly associated with cervical (odds ratio [OR] 7.34, 95% confidence interval [CI] 4.27, 12.6), breast (OR 3.29, 95% CI 2.0, 5.42), and colorectal (OR 3.02, 95% Cl 1.74, 5.23) cancer screening adherence. The report of a usual source of care was similarly positively associated with cervical, breast, and colorectal cancer screening adherence. Additional predictors for colorectal cancer screening included higher educational attainment (OR 1.56, 95% Cl 1.07, 2.28), and the presence of a comorbid condition (OR 1.54, 95% CI 1.16, 2.05). Experiencing discrimination (OR .42, 95% Cl .20, .89) and never being married (OR .49, 95% CI .27, .89) were negative predictors of breast cancer screening, while having insurance (OR 2.00, 95% CI 1.27, 3.15) was a positive predictor. Cervical cancer screening was positively associated with living at or above 300% of the federal poverty level (OR 2.69, 95% CI 1.50, 4.85)., Conclusions: Regular access to health care and a physician are the most consistent predictors of cancer screening adherence among Native Americans and should represent a focus of activities to improve screening rates in these communities. more...

Objective: Doctors often use medical language with their patients despite findings from a variety of studies that have shown that patients frequently misunderstand medical terminology. Little is known about the patterns of medical word use by doctors and patients during clinical encounters., Methods: A content analysis of 16 verbatim transcripts of first clinical encounters between rheumatologists and newly referred patients was conducted to assess how doctors and patients introduced medical words. Medical words were identified via a computer program using a defined list., Results: Doctors did not introduce or use more medical words than patients, but the types of words that doctors and patients introduced did differ. The majority of patient-initiated medical words occurred during the history taking (94%). Doctors did not explain, or use as part of an explanation, the majority (79%) of the medical words they introduced, and patients seldom responded in a way that would indicate whether or not they had correctly interpreted those terms. There was relatively little repetition of medical words within or even across encounters., Conclusions: This study provides insights into how the use of medical terminology could contribute to misunderstanding. Findings suggest that steps already promoted in the literature to improve doctor-patient communication may also ameliorate potential problems arising from the use of medical terminology. more...

Patient-centered interactive communication between physicians and patients is recommended to improve the quality of medical care. Numerical concepts are important components of such exchanges and include arithmetic and use of percentages, as well as higher level tasks like estimation, probability, problem-solving, and risk assessment--the basis of preventive medicine. Difficulty with numerical concepts may impede communication. The current evidence on prevalence, measurement, and outcomes related to numeracy is presented, along with a summary of best practices for communication of numerical information. This information is integrated into a hierarchical model of mathematical concepts and skills, which can guide clinicians toward numerical communication that is easier to use with patients. more...

This work is intended to be a mathematical underpinning for the field of grain-boundary engineering and its relatives. The inter-relationships within the set of rotations producing coincident site lattices in cubic crystals are examined in detail. Besides combining previously established but widely scattered results into a unified context, the present work details newly developed representations of the group structure in terms of strings of generators (based on quaternionic number theory, and including uniqueness proofs and rules for algebraic manipulation) as well as an easily visualized topological network model. Important results that were previously obscure or not universally understood (e.g. the Sigma combination rule governing triple junctions) are clarified in these frameworks. The methods also facilitate several general observations, including the very different natures of twin-limited structures in two and three dimensions, the inadequacy of the Sigma combination rule to determine valid quadruple nodes, and a curious link between allowable grain-boundary assignments and the four-color map theorem. This kind of understanding is essential to the generation of realistic statistical models of grain-boundary networks (particularly in twin-dominated systems) and is especially applicable to the field of grain-boundary engineering. more...

We present the measurement of the force required to rupture a single protein-sugar bond using a methodology that provides selective discrimination between specific and nonspecific binding events and helps verify the presence of a single functional molecule on the atomic force microscopy tip. In particular, the interaction force between a polymer-tethered concanavalin-A protein (ConA) and a similarly tethered mannose carbohydrate was measured as 47 +/- 9 pN at a bond loading rate of approximately 10 nN/s. Computer simulations of the polymer molecular configurations were used to determine the angles that the polymers could sweep out during binding and, in conjunction with mass spectrometry, used to separate the angular effects from the effects due to a distribution of tether lengths. We find that when using commercially available polymer tethers that vary in length from 19 to 29 nm, the angular effects are relatively small and the rupture distributions are dominated by the 10-nm width of the tether length distribution. In all, we show that tethering both a protein and its ligand allows for the determination of the single-molecule bond rupture force with high sensitivity and includes some validation for the presence of a single-tethered functional molecule on the atomic force microscopy tip. more...

The goal of this work is to study the properties of living cells and cell membranes by using atomic force microscopy. During atomic force microscopy (AFM) measurement, there is a strong mechanical coupling between the AFM tip and the cell. The purpose of this paper is to present a model of the overall mechanical response of the cell that allows us to separate out the mechanical response of the cell from the local surface interactions we wish to quantify. These local interactions include recognition (or binding) events between molecules bound to an AFM tip (e.g., an antibody) and molecules or receptors on the cell surface (e.g., the respective antigen). The computational model differs from traditional Hertzian contact models by explicitly taking into account the mechanics of the biomembrane and cytoskeleton. The model also accounts for the mechanical response of the living cell during arbitrary deformation. The indentation of a bovine sperm cell is used to test the validity of this model, and further experiments are proposed to fully parameterize the model. more...