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We report the results of the second charged-particle transport coefficient code comparison workshop, which was held in Livermore, California on 24–27 July 2023. This workshop gathered theoretical, computational, and experimental scientists to assess the state of computational and experimental techniques for understanding charged-particle transport coefficients relevant to high-energy-density plasma science. Data for electronic and ionic transport coefficients, namely, the direct current electrical conductivity, electron thermal conductivity, ion shear viscosity, and ion thermal conductivity were computed and compared for multiple plasma conditions. Additional comparisons were carried out for electron–ion properties such as the electron–ion equilibration time and alpha particle stopping power. Overall, 39 participants submitted calculated results from 18 independent approaches, spanning methods from parameterized semi-empirical models to time-dependent density functional theory. In the cases studied here, we find significant differences—several orders of magnitude—between approaches, particularly at lower temperatures, and smaller differences—roughly a factor of five—among first-principles models. We investigate the origins of these differences through comparisons of underlying predictions of ionic and electronic structure. The results of this workshop help to identify plasma conditions where computationally inexpensive approaches are accurate, where computationally expensive models are required, and where experimental measurements will have high impact. [ABSTRACT FROM AUTHOR]

Background and Aims: Participating in online gambling is associated with an increased risk for experiencing gambling‐related harms, driving calls for more effective, personalized harm prevention initiatives. Such initiatives depend on the development of models capable of detecting at‐risk online gamblers. We aimed to determine whether machine learning algorithms can use site data to detect retrospectively at‐risk online gamblers indicated by the Problem Gambling Severity Index (PGSI). Design: Exploratory comparison of six prominent supervised machine learning methods (decision trees, random forests, K‐nearest neighbours, logistic regressions, artificial neural networks and support vector machines) to predict problem gambling risk levels reported on the PGSI. Setting: Lotoquebec.com (formerly espacejeux.com), an online gambling platform operated by Loto‐Québec (a provincial Crown Corporation) in Quebec, Canada. Participants: N = 9145 adults (18+) who completed the survey measure and placed at least one bet using real money on the site. Measurements Participants completed the PGSI, a self‐report questionnaire with validated cut‐offs denoting a moderate‐to‐high‐risk (PGSI 5+) or high‐risk (PGSI 8+) for experiencing past‐year gambling‐related problems. Participants agreed to release additional data about the preceding 12 months from their user accounts. Predictor variables (144) were derived from users' transactions, apparent betting behaviours, listed demographics and use of responsible gambling tools on the platform. Findings Our best classification models (random forests) for the PGSI 5+ and 8+ outcome variables accounted for 84.33% (95% CI = 82.24–86.41) and 82.52% (95% CI = 79.96–85.08) of the total area under their receiver operating characteristic curves, respectively. The most important factors in these models included the frequency and variability of participants' betting behaviour and repeat engagement on the site. Conclusions: Machine learning algorithms appear to be able to classify at‐risk online gamblers using data generated from their use of online gambling platforms. They may enable personalized harm prevention initiatives, but are constrained by trade‐offs between their sensitivity and precision. [ABSTRACT FROM AUTHOR]

Since the start of the COVID-19 pandemic, a steady stream of propositions from tech giants and start-ups alike has furnished us with the idea that GPS- or Bluetooth-enabled contact tracing apps are a vital part of the pandemic response. This commentary considers these apps as 'corporate contact tracing', emphasizing the private-sector role that such developments imply. We first discuss corporate contact tracing's potential to de-center the power of public health authorities. Then, using the frames of surveillance capitalism and disaster capitalism, we suggest how corporate contact tracing might feed the rise of corporate power in the public sphere. We question its capacity to address structural inequalities and to foster a social justice vision of public health. And, we wonder whether corporate contact tracing might intensify the effects of discriminatory design and algorithmic oppression. We conclude by calling for a discussion of this technology beyond questions of privacy and efficacy. [ABSTRACT FROM AUTHOR]

The Meaningful Involvement of People with HIV/AIDS (MIPA) has been at the core of the HIV response since the beginning of the HIV epidemic. In this study, we compare two community engagement activities concerned with molecular HIV surveillance (MHS) in the United States: one governmental and one community-led. We examine the consultative aspects of each one, especially as they relate to people living with HIV. We point to the community-based effort--which used a participatory praxis approach--as an example of MIPA. We derive two best practice principles from this research from the field. [ABSTRACT FROM AUTHOR]

This article examines Canada's first internet gambling website blocking scheme, which was enacted in Quebec as part of the implementation of the province's 2015 budget. Using qualitative research methods, the article illustrates the complexities of regulating online gambling. Influenced by critical sociological and anthropological studies of gambling, and taking a socio-legal, governmentality perspective, it shows how socio-legal studies can illuminate research on the regulation of gambling, and how the study of online gambling can, as a sentinel site for the regulation of online consumption, contribute to the development of socio-legal studies. Our analysis shows that the governmentality of online gambling is framed so as to exclude 1) a range of risks (e.g., related to consumer profiling and the capacity to stimulate "addictive consumption"), 2) the heterogeneity of everyday experience that connects online gambling with online addictive consumption more generally, and 3) a range of possibilities for governing online gambling otherwise. [ABSTRACT FROM AUTHOR]

The transformation of games with the advent of platformized distribution systems continues to produce new and agile forms of consumption and exploitation. Valve Corporation's DOTA 2 is a key example of a gaming space that is constantly atomized and rebuilt with the aim of optimizing player participation. This participatory form is ever-more gamblified and framed by systems designed to habituate players to a new form of consumption. This article explores how DOTA 2 transforms every year with the advent of a yearly Battle Pass, brimming with gambling systems aimed at eliciting specific forms of user participation. We catalog and schematize these systems with the aim of shedding light on the inner workings of DOTA 2 during this season. The purpose of our work is to move the discussion beyond a regulatory focus on symptomatic loot boxes and toward a deeper understanding of the rhetorical systems hiding beneath game systems. [ABSTRACT FROM AUTHOR]

The miscibility gap in hydrogen-water mixtures is investigated by conducting Gibbs-ensemble Monte Carlo simulations with analytical two-body interaction potentials between the molecular species. We calculate several demixing curves at pressures below 150 kbar and temperatures of 1000 K ≤ T ≤ 2000 K. Despite the approximations introduced by the two-body interaction potentials, our results predict a large miscibility gap in hydrogen-water mixtures at similar conditions as found in experiments. Our findings are in contrast to those from ab initio simulations and provide a renewed indication that hydrogen-water immiscibility regions may have a significant impact on the structure and evolution of ice giant planets like Uranus and Neptune. [ABSTRACT FROM AUTHOR]

We show how equations of state generated by density functional theory methods can be augmented to match experimental data without distorting the correct behavior in the high- and low-density limits. The technique is thermodynamically consistent and relies on knowledge of the density and bulk modulus at a reference state and an estimation of the critical density of the liquid phase. We apply the method to four materials representing different classes of solids: carbon, molybdenum, lithium, and lithium fluoride. It is demonstrated that the corrected equations of state for both the liquid and solid phases show a significantly reduced dependence of the exchange-correlation functional used. [ABSTRACT FROM AUTHOR]

Regulatory approaches to games are organized by boundaries between game/not-game, game/gambling game, skilled/unskilled play, consumption/production. Perhaps more importantly, moral justifications for regulating gambling (and condemning digital games) are rooted in the idea that they consume our time and wages but give little in return. This article uses two case studies to show how these boundaries and justifications are now perforated and reconfigured by digital mediation. The case study of Daily Fantasy Sports (DFS) illustrates a contemporary challenge to rigid dichotomies between game/not game, skilled/unskilled play, and game/gambling game, demonstrating how regulation becomes deterritorialized as gambling moves out of state-regulated physical casinos and takes the form of networked, digital games. Our second case study of Pokémon Go approaches regulation from a different direction, complicating the rigid dichotomy between production/consumption in online networked play. We show how play is increasingly realized as productive in economic, social, physical, subjective and analytic registers, while at the same time, it is driven by gambling design imperatives, such as extending time-on-device. Pokémon Go exemplifies analytic productivity, a term we use to refer to the production of data flows that can be leveraged for a wide variety of purposes, including to predict, shape, and channel the behaviour of player populations, thereby generating multiple streams of revenue. Ultimately, both cases illustrate how digital games and gambling increasingly blur into each other, complicating the regulatory landscape. [ABSTRACT FROM AUTHOR]

The rise of platforms as the premier model of videogame distribution has led to a number of changes in the business models of producers and distributors. Consumers are constantly hailed by games platforms through freemium business models that offer cosmetic items contained in loot boxes or recurring subscriptions. Thus far, game studies and consumer studies have been unable to account for the totality of how these new and dynamic platforms circumvent legal barriers and attract potential consumers. This paper argues that a hybrid research model combining platform studies, socio-cultural critique of gamblification, and political economy is required in order to theorize and explicate how these platforms operate. The platformized and gamblified model for game distribution seeks to regulate and configure networks of association between consumers and producers with the ultimate aim of eliciting participation on platforms. [ABSTRACT FROM AUTHOR]

We present an equation of state as well as a phase diagram of ammonia at high pressures and high temperatures derived from ab initio molecular dynamics simulations. The predicted phases of ammonia are characterized by analyzing diffusion coefficients and structural properties. Both the phase diagram and the subsequently computed Hugoniot curves are compared to experimental results. Furthermore, we discuss two methods that allow us to take into account nuclear quantum effects, which are of considerable importance in molecular fluids. Our data cover pressures up to 330 GPa and a temperature range from 500 K to 10 000 K. This regime is of great interest for interior models of the giant planets Uranus and Neptune, which contain, besides water and methane, significant amounts of ammonia. [ABSTRACT FROM AUTHOR]

In the article, the authors discuss how the politics of prevention can be used as a heuristic device to reflect on the key dimensions of public health response to the COVID-19 pandemic. They cite the situation in Ontario to examine the challenges and tensions that arose in learning about the pandemic and implementing public health measures to prevent it. Also cited are the possible adverse social effects of prevention strategies against infectious diseases.

We are currently in the midst of a global pandemic with the spread of Coronavirus Disease 2019 (COVID-19). While we do not know how this situation will unfold or resolve, we do have insight into how it fits within existing patterns and relations, particularly those pertaining to sociocultural constructions of (in)security, vulnerability, and risk. We can see evidence of surveillance dynamics at play with how bodies and pathogens are being measured, tracked, predicted, and regulated. We can grasp how threat is being racialized, how and why institutions are flailing, and how social media might be fueling social divisions. There is, in other words, a lot that our scholarly community could add to the conversation. In this rapid-response editorial, we provide an introduction to the framing devices of disease surveillance and discuss how a surveillance studies orientation could help us think critically about the present crisis and its possible aftermath. [ABSTRACT FROM AUTHOR]

The thermal conductivity of partially dissociated and ionised water is calculated in a large-scale study using density functional theory (DFT)-based molecular dynamics (MD) simulations. In doing so, the required heat current of the nuclei is calculated by mapping the effective particle interactions from the DFT-MD simulations onto classical pair potentials. It is demonstrated that experimental and theoretical thermal conductivity data for liquid heavy water and for ice VII are well reproduced with this efficient procedure. Moreover, the approach also allows for an illustrative interpretation of the characteristics of the thermal conductivity in the dense chemically reacting fluid. The thermodynamic conditions investigated here range from densities between 0.2 and 6 g cm−3 and temperatures between 600 and 50 000 K, which includes states highly relevant for understanding the interiors of water-rich planets like Uranus and Neptune and exoplanets of similar composition. [ABSTRACT FROM AUTHOR]

Background: Emphasis on HIV testing as a gateway to prevention, treatment and care has grown tremendously over the past decade. In turn, this emphasis on testing has created a demand for new policies, programs, and technologies that can potentially increase access to and uptake of HIV testing. HIV self-testing (HST) technologies have gained important momentum following the approval of the over-the-counter self-tests in the United States, the UK, and France. While the renewed interest in HST has given rise to a number of high quality reviews of empirical studies conducted on this topic, we have yet to find an article that captures the extent of the debate on HST. Mapping the debate: A critical review of the literature on HST was conducted and organized into three categories based on the focus of the article: 1) Empirical research, 2) Arguments, and 3) Context. We focused exclusively on the second category which included ethical analyses, policy analyses, editorials, opinion pieces, commentaries, letters to the editor and so forth. 10 lines of argument on HST were identified in the literature: 1) Individual - Public Health, 2) Strengths - Limits, 3) Benefits - Harms, 4) Screening - Testing, 5) Target - Market, 6) Health Care - Industry, 7) Regulation - Restriction, 8) Resource-Rich Settings - Resource-Limited Settings, 9) Ethical - Unethical, and 10) Exceptionalism - Normalization. Each line of argument is presented and discussed in the paper. Conclusion: We conclude by providing examples of critical questions that should be raised in order to take the debate to another level and generate new ways of thinking about HST. [ABSTRACT FROM AUTHOR]

We use ab initio simulations based on density functional theory to calculate the electrical and thermal conductivities of electrons in partially ionized water plasmas at densities above 0.1 g/cm³. The resulting conductivity data are then fitted to analytic expressions for convenient application. For low densities, we develop a simple and fully analytic model for electronic transport in lowdensity plasmas in the chemical picture using the relaxation-time approximation. In doing so, we derive a useful analytic expression for electronic transport cross sections with neutral particles, based on a model potential. In the regime of thermal ionization, electrical conductivities from the analytic model agree with the ab initio data within a factor of 2. Larger deviations are observed for the thermal conductivity, and their origin is discussed. Our results are relevant for modeling the interior and evolution of water-rich planets as well as for technical plasma applications. [ABSTRACT FROM AUTHOR]

This article provides an introduction to a special issue of Body & Society that explores the surveillance—embodiment nexus. It accentuates both the prevalence and consequence of bodies being increasingly converted into ‘objects of information’ by surveillance technologies and systems. We begin by regarding the normalcy of body monitoring in contemporary life, illustrating how a plurality of biometric scanners operate to intermediate the physical surfaces and subjective depths of bodies in accordance with various concerns. We focus on everyday experiences of bodily intermediation by surveillant dispositifs, and consider the broader political, epistemological, and ontological significance of these processes. We then point to the substantive intersections and divergences existing between body and surveillance studies. We conclude with an overview of the five articles appearing in this special issue. We describe how each contribution creates a template for imagining what a body is, and what a body might become, in a culture defined by proliferating data sharing behaviours, systems of codification, and practices of intermediation. [ABSTRACT FROM AUTHOR]

HIV criminalisationis a term that describes the criminal prosecution of persons in instances of HIV transmission, exposure and so-called non-disclosure of their HIV serostatus. In the United States (US), there have been over 500 reported instances of HIV criminalisation. Over the past decade, several negative consequences of HIV criminalisation have been identified, including its capacity to increase stigma and social injustice. In addition, scholars have built an evidence base demonstrating that HIV criminalisation has the potential to undermine HIV prevention and that it is thus harmful to public health. This article contributes to that evidence base by (1) combining Foucaultian studies of ‘governmentality’ with the sociology of ‘anomie’ to theorise the larger implications of HIV criminalisation for the institution of public health, and (2) presenting interviews with public health service providers working in Tennessee, USA. This state is an important site for studying the public health implications of HIV criminalisation because, between 2008 and 2012, it was reported to have led all American jurisdictions in prosecutions of HIV-specific criminal offences. Concentrating on discussions of post-test counselling, this article argues that a major system-level effect of HIV criminalisation is the propagation of an anomic affective climate, which makes it difficult to establish norms of HIV prevention. [ABSTRACT FROM PUBLISHER]

We employ a combination of density functional theory (DFT), molecular dynamics (MD), and a variety of advanced postprocessing methods to construct an analytic thermodynamic potential (free energy) for ices VII and X. In particular, the temperature-dependent part of the free energy function is constructed using entropy data obtained via the spectrum of vibrational modes from the MD simulations. Conceptional challenges due to the partial absence of stable zero-temperature states and proton disorder are overcome by performing calculations of representative crystalline states combined with a three-stage fitting procedure of data from MD simulations and static DFT calculations. The influence of the exchange-correlation functional is extensively discussed, and a comparison with available experiments is made as well and generally shows good agreement. This work is of significant importance for astrophysical applications, such as the interior modeling of dense icy planets and moons. [ABSTRACT FROM AUTHOR]

We employ ab initio simulations based on density functional theory (DFT) to calculate the electronic transport coefficients (electrical conductivity, thermal conductivity, and thermopower) of molybdenum over a broad range of thermodynamic states. By comparing to available experimental data, we show that DFT is able to describe the desired transport properties of this refractory metal with high accuracy. Most noteworthy, both the positive sign and the quantitative values of the thermopower of solid molybdenum are reproduced very well. We calculate the electrical and thermal conductivity in the solid and the fluid phase between 1000 and 20 000 K and a wide span in density and develop empirical fit formulas for direct use in practical applications, such as magneto-hydrodynamics simulations. The influence of thermal expansion in conductivity measurements at constant pressure is also discussed in some detail. [ABSTRACT FROM AUTHOR]

Many works that may be situated within the interdisciplinary field of Surveillance Studies have described dangerous potentialities associated with the pervasive, IT-mediated merger of once discrete data sets. In effect, these works cautioned about the rise of "big data" before it was named as such. Even so, they share an uncomfortable consonance with euphoric claims about the revolutionary transformation portended by big data. Situating both euphoric and critical accounts of the IT-mediated gaze within a larger informatic ethos--a spirit in the Weberian sense of this term, defined above all by its concealment of the labor that makes IT work--this article argues that discourse on the data-driven, information revolution must be supplemented by a more modest discourse empirically rooted in the everyday, pragmatic realities of IT. Where it departs from well-established social scientific analyses of IT, however, is in its development of a novel concept: informatic practice. Informatic practice may be defined as the sum of labor or activity that materializes information, including, for instance, such mundane activities as data entry. To empirically illustrate some complexities associated with informatic practice, this article discusses process challenges associated with the implementation of a large-scale (or "big"), regionally interconnected public health information system in Ontario, Canada. Informed by science and technology studies (STS) and actor-network theory (ANT), it uses documentary evidence and interviews with 38 key informants to describe informatic practice and to illustrate the mutations--the natural change--introduced into the IT-mediated gaze by everyday, material practices. This complicates both critical and euphoric claims about big data. [ABSTRACT FROM AUTHOR]

We present a method to calculate ionic conductivities of complex fluids from ab initio simulations. This is achieved by combining density functional theory molecular dynamics simulations with polarization theory. Conductivities are then obtained via a Green-Kubo formula using time-dependent effective charges of electronically screened ions. The method is applied to two different phases of warm dense water. We observe large fluctuations in the effective charges; protons can transport effective charges greater than + e for ultrashort time scales. Furthermore, we compare our results with a simpler model of ionic conductivity in water that is based on diffusion coefficients. Our approach can be directly applied to study ionic conductivities of electronically insulating materials of arbitrary composition, e.g., complex molecular mixtures under such extreme conditions that occur deep inside giant planets. [ABSTRACT FROM AUTHOR]

Using Kubo's linear response theory, we derive expressions for the frequency-dependent electrical conductivity (Kubo-Greenwood formula), thermopower, and thermal conductivity in a strongly correlated electron system. These are evaluated within ab initio molecular dynamics simulations in order to study the thermoelectric transport coefficients in dense liquid hydrogen, especially near the nonmetal-to-metal transition region. We also observe significant deviations from the widely used Wiedemann-Franz law, which is strictly valid only for degenerate systems, and give an estimate for its valid scope of application toward lower densities. [ABSTRACT FROM AUTHOR]

We calculate optical properties of water along the principal Hugoniot curve from ambient conditions up to temperatures of 130 000 K with density functional theory (DFT) and the Kubo-Greenwood formula. The effect of the exchange correlation functional is examined by comparing the generalized gradient approximation with a hybrid functional that contains Fock exchange. We find noticeable but moderate differences between the respective results which decrease rapidly above 80 000 K. The reflectivity along the principal Hugoniot is calculated and a good qualitative but fair quantitative agreement with available experimental data is found. Our results are of general relevance for calculations of optical properties with DFT at zero and elevated temperature. [ABSTRACT FROM AUTHOR]

This article considers the imbrication of war-time logics with the ideational and institutional development of public health surveillance. It suggests that, as the Cold-War-era gave way to the 'age of globalization', public health discourse became less concerned with ideological enemies, and more concerned with ontological enemies. The discourse of emerging infectious disease exemplifies this preoccupation and illustrates how public health surveillance, dominated by war-time logics, is both globalized and predisposed to marginalized local orders of concern. However, at the same time that militarized configurations of public health surveillance set certain tendencies in motion, local orders of concern deconstruct, contest, resist, and negotiate these tendencies. Hence, this article concludes with a call for further empirical attention by Surveillance Studies scholars to the multiplicity of local sites that enact public health surveillance. [ABSTRACT FROM AUTHOR]

Discusses Canadian policy responses to the acts of terrorism on September 11, 2001. Status of public sector privacy legislation in Canada; Powers of arrest and detention; Discussion on international travel.

A compact and robust long-wavelength fluorescence detection system (LWFDS) has been constructed using a pulsed diode laser as the light source and a photodiode detector. The detection limits for naphthofluorescein (NF) and the cyanine dyes Cy5 and Cy5.5 at pH 8.8, determined using the LWFDS, were 1.0×10−10, 2.3×10−12 and 6.2×10−11 M, respectively. These values compared favourably with data from a commercial research grade fluorescence spectrometer. The LWFDS instrument was used as the detector for a competitive heterogeneous flow injection immunoassay for α-interferon with Cy5 as the label. A calibration graph usable over the range 0.5–10 μg ml−1 α-interferon was obtained. The instrument demonstrated its potential for rapid (<200 s per sample) multi-analyte assays and for field monitoring. [Copyright &y& Elsevier]

SUMMARY Leiomyomas of the oesophagus are uncommon, and have not been reported in patients infected with the human immunodeficiency virus (HIV). A case of an oesophageal leiomyoma in an adult infected with HIV is presented. [ABSTRACT FROM AUTHOR]

The electrical σ and thermal conductivity λ of liquid iron are calculated with spin-polarized density-functional-theory-based simulations over a significant pressure and temperature range using the Kubo-Greenwood formalism. We show that a paramagnetic state is stable in the liquid up to high temperatures at ambient pressure and that the discrepancy between experimental results and spin-degenerate simulations for σ and λ of more than 30% are reduced to within 10% with lower values resulting from the spin-polarized simulations. Along the 3700 K isotherm, we explore the persistence of magnetic fluctuations toward high densities, and beyond 20-50 GPa the liquid becomes diamagnetic, which suggests the existence of a continuous paramagnetic-to-diamagnetic transition. This transition exerts a significant influence on the physical properties of liquid iron, especially on σ and λ, and is potentially of high relevance for dynamo processes in Mercury and Mars. [ABSTRACT FROM AUTHOR]

In recent years, there has been an explosion of "experiential design" in casinos, driven in part by research suggesting that curating gambling sensescapes can lure patrons to spend more time – and money – inside the casino. Building on the promise of existing casino ethnographies, this paper argues that a sensory ethnographic approach to the study of gambling environments can offer valuable insight into the experiential design and mood management of the casino. We use sensory ethnography to explore the ambiance of the Montreal Casino, particularly during the casino's "Vegas Nights" promotion. How does the casino feel (and how does it touch back)? What rhythms flow through its neon labyrinth? What does "getting a real taste of Vegas," well ... taste like? Moreover, we position this ambiance at the center of the casino's "push-and-pull" approach to problem gambling – where this government-affiliated sensory extravaganza must toe a tenuous line between attraction and responsibilisation. In addition, we examine how the ambiance of the casino is co-produced by patrons and employees. Ultimately, we argue that the casino floor is unlike a sensory research laboratory – for here, sensations mix and mingle, and it takes a sensory ethnographer to quite literally "make sense" of the casino ambiance and its impact on visitor experience. [ABSTRACT FROM AUTHOR]

We present new results in modeling the interiors of Giant Planets (GP) and Brown Dwarfs (BD). In general models of the interior rely on equation of state data for planetary materials which have considerable uncertainties in the high-pressure domain. Our calculations are based on ab initio equation of state (EOS) data for hydrogen, helium, hydrogen-helium mixtures and water as the representative of all heavier elements or ices using finite-temperature density functional theory molecular dynamics (FT-DFT-MD) simulations. We compare results for the BD Gliese 229B calculated with Saumon-Chabrier-Van Horn EOS (SCVH95) and our EOS data. [ABSTRACT FROM PUBLISHER]

We construct thermodynamic potentials for two superionic phases of water [with body-centered cubic (bcc) and face-centered cubic (fcc) oxygen lattice] using a combination of density functional theory (DFT) and molecular dynamics simulations (MD). For this purpose, a generic expression for the free energy of warm dense matter is developed and parametrized with equation of state data from the DFT-MD simulations. A second central aspect is the accurate determination of the entropy, which is done using an approximate two-phase method based on the frequency spectra of the nuclear motion. The boundary between the bcc superionic phase and the ices VII and X calculated with thermodynamic potentials from DFT-MD is consistent with that directly derived from the simulations. Differences in the physical properties of the bcc and fcc superionic phases and their impact on interior modeling of water-rich giant planets are discussed. [ABSTRACT FROM AUTHOR]