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BACKGROUND: Few interventions have focused on improving end-of-life care for underserved populations, such as homeless persons. OBJECTIVE: To determine whether homeless persons will complete a counseling session on advance care planning and fill out a legal advance directive designed to assess care preferences and preserve the dignity of marginalized persons. DESIGN: Prospective, single-blind, randomized trial comparing self-guided completion of an advance directive with professionally assisted advance care planning. (ClinicalTrials.gov registration number: NCT00546884) SETTING: 8 sites serving homeless persons in Minneapolis, Minnesota. PARTICIPANTS: 262 homeless persons recruited between November 2007 and August 2008. INTERVENTION: Minimal, self-guided intervention consisting of advance directive forms and written educational information versus a one-on-one advance planning intervention consisting of counseling and completing an advance directive with a social worker. MEASUREMENTS: Rate of advance directive completion, assessed by inspection of completed documents. RESULTS: The overall completion rate for advance directives was 26.7% (95% CI, 21.5% to 32.5%), with a higher rate in the counselor-guided group (37.9%) than in the self-guided group (12.8%) (CI of adjusted difference, 15.3 to 34.3 percentage points). This difference persisted across all sites and most subgroups. The advance directive's 4 clinical scenarios found a preference for surrogate decision making in 29% to 34% of written responses. LIMITATIONS: Sampling was limited to a more stable subset of the homeless population in Minneapolis and may have been subject to selection bias. Modest compensation to complete the preintervention survey could have influenced participants to complete advance directives. CONCLUSION: Both a simple and complex intervention successfully engaged a diverse sample of homeless persons in advance care planning. One-on-one assistance significantly increased the completion rate. Homeless persons can respond to an intervention to plan for end-of-life care and can express specific preferences for care or a surrogate decision maker, but additional studies are needed to assess the effect of these directives on subsequent care. PRIMARY FUNDING SOURCE: National Institute for Nursing Research and National Center on Minority Health and Health Disparities. [ABSTRACT FROM AUTHOR]

Patient cultural backgrounds strongly influence decision-making processes and outcomes in genetic counseling. The present study investigated influences of culture and acculturation on prenatal decision making processes of native Palestinians and Palestinian Americans. Seventeen native Palestinians and 14 first-generation, Palestinian Americans were interviewed and asked to imagine themselves as patients in hypothetical premarital and prenatal situations. Five major issues were investigated: 1) Influence of family history of an inherited condition on pre-marital decisions; 2) Perceptions of non-directive genetic counselor statements regarding options; 3) Role of gender in prenatal decisions; 4) Gender differences in emotional expression; and 5) Role of family and society in prenatal decisions. Several similarities and differences in native Palestinian and Palestinian American responses were obtained. Similarities appear to be due to common cultural roots, while differences may be due to acculturation. Practice and research recommendations are provided. [ABSTRACT FROM AUTHOR]

Personal values are motivational sources for an individual's actions [Hitlin and Piliavin (Annual Review of Sociology 30:359-393, 2004)]. Genetic counselors' values may influence their behaviors in clinical practice, but a profile of their personal values has not been identified empirically. In this study, 292 genetic counselors completed the Schwartz Universal Values Questionnaire (SUVQ; Schwartz, S. H. (1992). Universals in the content and structure of values: Theoretical advances and empirical tests in 20 countries. In M. Zanna (Ed.), Advances in experimental social psychology (pp. 1-65). Boston, MA: Academic.), a widely used measure of value types, and provided information about their demographic characteristics. Results indicate that respondents highly valued benevolence, self-direction, achievement, and universalism indicating a strong pattern of concern for the welfare of others. They placed considerably less value on stimulation, tradition, and power, which reflect personal interests. Respondents who reported practicing a religion scored significantly lower on stimulation and hedonism and higher on tradition and spirituality than those not practicing; married respondents and parents scored significantly lower on stimulation and achievement; and males scored higher on power than females. The value types are described, and training and research recommendations are provided. [ABSTRACT FROM AUTHOR]

There is limited research about ethical and professional dilemmas that genetic counselors encounter in their practice and their strategies for addressing them. In this study, 454 genetic counselors rated the frequency with which they encounter each of 16 ethical/professional challenges identified and categorized previously (McCarthy Veach P, Bartels DM, LeRoy BS (2001) J Genet Couns 10(2):97-119). Over 40% indicated these issues occurred frequently: patient emotions, diversity, financial constraints, uncertainty, and colleague error. Two hundred and fifty-five respondents provided personal anecdotes describing exceptionally challenging situations and recommended strategies for addressing them. Most of their anecdotes involved informed consent, value conflicts, confidentiality, colleague error, withholding information, and resource allocation. The most frequently recommended strategies were further discussion with patient, consultation with other professionals, and referral to other health sources. Thirty-five respondents were unable to/did not offer strategies. Respondent demographics were not related to frequency of issues, type of anecdote, or recommended strategies. Practice, policy, and research implications are discussed. [ABSTRACT FROM AUTHOR]

Ninety-seven physicians, nurses, and genetic counselors from four regions within the United States participated in focus groups to identify the types of ethical and professional challenges that arise when their patients have genetic concerns. Responses were taped and transcribed and then analyzed using the Hill et al. (1997, Counsel Psychol 25:517-522) Consensual Qualitative Research method of analysis. Sixteen major ethical and professional domains and 63 subcategories were identified. Major domains are informed consent; withholding information; facing uncertainty; resource allocation; value conflicts; directiveness/nondirectiveness; determining the primary patient; professional identity issues; emotional responses; diversity issues; confidentiality; attaining/maintaining proficiency; professional misconduct; discrimination; colleague error; and documentation. Implications for practitioners who deal with genetic issues and recommendations for additional research are given. [ABSTRACT FROM AUTHOR]

Twenty-eight former genetic counseling clients seen at a major Midwestern university were recruited to be interviewed about their genetic counseling experiences, including most and least helpful aspects, what they learned, how this information impacted their decision-making, and their perceptions of their genetic counselors' behaviors. Responses were inductively analyzed, and several themes were identified, including: Clients sought genetic counseling to obtain genetic-medical information; a majority accurately recalled this information; genetic counseling influenced decisions for about 50% of the sample; decision-making was affected by several extra-session factors; a majority experienced distress during the session; most perceived genetic counselor responses as nondirective and liked this approach; counselor behaviors regarded as directive involved discussion of pregnancy termination; participants disagreed about the need for and provision of genetic counselor support; most regarded the session as helpful and stated that they would seek genetic counseling again. Suggestions for addressing these issues in practice and research are given. [ABSTRACT FROM AUTHOR]

It is known that glow discharges with a water anode inject and form solvated electrons at the plasma-liquid interface, driving a wide variety of reduction reactions. However, in systems with a water cathode, the production and role of solvated electrons are less clear. Here, we present evidence for the direct detection of solvated electrons produced at the interface of an argon plasma and a water cathode via absorption spectroscopy. We further quantify their yield using the dissociative electron attachment of chloroacetate, measuring a yield of 1.04 ± 0.59 electrons per incident ion, corresponding to approximately 100% faradaic efficiency. Additionally, we estimate a yield of 2.09 ± 0.93 hydroxyl radicals per incident ion. Comparison of this yield with other findings in the literature supports that these hydroxyl radicals are likely formed directly in the liquid phase rather than by diffusion from the vapor phase.

Many questions remain about the reactions of the hydrated electron despite decades of study. Of particular note is that they do not appear to follow the Marcus theory of electron transfer reactions, a feature that is yet to be explained. To investigate these issues, we used ab initio molecular dynamics (AIMD) simulations to investigate one of the better studied reactions, the hydrated electron reduction of CO 2 . The rate constant for the hydrated electron-CO 2 reaction complex to react to form CO 2 - is for the first time estimated from AIMD simulations. Results at 298 and 373 K show the rate constant is insensitive to temperature, consistent with the low measured activation energy for the reaction, and the implications of this behavior are examined. The sampling provided by the simulations yields insight into the reaction mechanism. The reaction is found to involve both solvent reorganization and changes in the carbon dioxide structure. The latter leads to significant vibrational excitation of the bending and symmetric stretch vibrations in the CO 2 - product, indicating the reaction is vibrationally nonadiabatic. The former is estimated from the calculation of an approximate collective solvent coordinate and the free energy in this coordinate is determined. These results indicate that AIMD simulations can reasonably estimate hydrated electron reaction activation energies and provide new insight into the mechanism that can help illuminate the features of this unusual chemistry.

The reactivity of chromium(III) species with the major oxidizing and reducing radiolysis products of water was investigated in aqueous solutions at temperatures up to 150 °C. The reaction between the hydrated electron (e aq - ) and Cr(III) species showed a positive temperature dependence over this temperature range. The reaction was also studied in pH 2.5 and 3.5 solutions for the first time. This work also studied the reaction between acidic Cr(III) species and the hydroxyl radical (⋅OH). It was found that Cr 3+ did not react significantly with the ⋅OH radical, but the first hydrolysis species, Cr(OH) 2+ , did with a rate coefficient of k= (7.2±0.3)×10 8  M -1  s -1 at 25 °C. The oxidation of Cr(OH) 2+ by the ⋅OH radical formed an absorbing product species that ultimately oxidized to give Cr(VI). These newly measured reaction rates allow for the development of improved models of aqueous chromium speciation for the effective remediation of liquid high-level nuclear waste via vitrification processes., (© 2023 Wiley-VCH GmbH.)

A large literature implicates time preference (i.e., how much an outcome retains value as it is delayed) as a predictor of a wide range of behaviors, because most behaviors involve sooner and delayed consequences. We aimed to provide the most comprehensive examination to date of how well laboratory-derived estimates of time preference relate to self-reports of 36 behaviors, ranging from retirement savings to flossing, in a test-rest design using a large sample ( N = 1,308) and two waves of data collection separated by 4.5 months. Time preference is significantly-albeit modestly-associated with about half of the behaviors; this is true even when controlling for 15 other demographic variables and psychologically relevant scales. There is substantial variance in the strengths of associations that is not easily explained. Time preference's predictive validity falls in the middle of these 16 possible predictors. Finally, we ask time preference researchers ( N = 55) to predict the variation in the relationship between time preference and behaviors, and although they are reasonably well-calibrated, these experts tend to overestimate the predictive power of time preference estimates. We discuss implications of invoking time preference as a predictor and/or determinant of behaviors with delayed consequences in light of our findings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Mixed quantum-classical molecular dynamics simulations have been important tools for studying the hydrated electron. They generally use a one-electron pseudopotential to describe the interactions of an electron with the water molecules. This approximation shows both the strength and weakness of the approach. On the one hand, it enables extensive statistical sampling and large system sizes that are not possible with more accurate ab initio molecular dynamics methods. On the other hand, there has (justifiably) been much debate about the ability of pseudopotentials to accurately and quantitatively describe the hydrated electron properties. These pseudopotentials have largely been derived by fitting them to ab initio calculations of an electron interacting with a single water molecule. In this paper, we present a proof-of-concept demonstration of an alternative approach in which the pseudopotential parameters are determined by optimizing them to reproduce key experimental properties. Specifically, we develop a new pseudopotential, using the existing TBOpt model as a starting point, which correctly describes the hydrated electron vertical detachment energy and radius of gyration. In addition to these properties, this empirically optimized model displays a significantly modified solvation structure, which improves, for example, the prediction of the partial molar volume.

Pulsed electron radiolysis was used to determine the chemical reaction kinetics and Arrhenius parameters for iron(II) reactions in aqueous solutions under irradiation. The second-order Fe 2+ reactions with the hydrated electron (e aq - ) and the perhydroxyl radical (HO 2 • ), arising from water radiolysis, were measured to high temperatures using custom-built flow-through cells with a multichannel optical detection system. The reaction with the HO 2 • radical was found to proceed via the formation of a metal-ion adduct species, Fe 2+ -HO 2 • . The adduct's molar extinction coefficient and its first-order decay rate coefficients are also reported.

It is now generally accepted that the hydrated electron occupies a cavity in water, but the size of the cavity and the arrangements of the solvating water molecules have not been fully characterized. Here, we use the Kirkwood-Buff (KB) approach to examine how the partial molar volume ( V M ) provides insight into these issues. The KB method relates V M to an integral of the electron-water radial distribution function, a key measure of the hydrated electron structure. We have applied it to three widely used pseudopotentials, and the results show that V M is a sensitive measure of the fidelity of hydrated electron descriptions. Thus, the measured V M places constraints on the hydrated electron structure that are important in developing and evaluating the model descriptions. Importantly, we find that V M does not reflect only the cavity size (and thus should not be used to infer the cavity radius) but is strongly dependent on the extended solvation structure.

Radiation chemistry of hydrated metal ions plays a significant role in the field of nuclear energy, especially regarding water radiolysis in coolant water in nuclear reactors. This work reports new experimental data on the reactivity of Ni 2+/+ species under critical conditions of temperature and pressure. The reaction rates of hydrated nickel ions with water radiolysis products (e - aq , • OH, H, and H 2 O 2 ) have been investigated for a 25-300 °C temperature range and 200 bar pressure using electron pulse radiolysis/transient absorption. Extensive experiments with the Ni 2+/+ species in various salts and pH up to 300 °C were performed. Kinetic decay traces of short-lived monovalent nickel ions were fitted to extract the rate constants versus temperature up to 300 °C. A blue shift of the absorption spectrum of the monovalent nickel ion with increasing temperature was demonstrated, which may indicate a change in the average coordination number. The Arrhenius parameters for the reactions of Ni 2+ with e - aq and Ni + with • OH, H, and H 2 O 2 were obtained. All measured rate constants increased with temperature and followed Arrhenius behavior.

Pulse radiolysis with a custom multichannel detection system has been used to measure the kinetics of the radiation chemistry reactions of aqueous solutions of chromium(VI) to 325 °C for the first time. Kinetic traces were measured simultaneously over a range of wavelengths and fit to obtain the associated high-temperature rate coefficients and Arrhenius parameters for the reactions of Cr(VI) + e aq - , Cr(VI) + H • , and Cr(V) + • OH. These kinetic parameters can be used to predict the behavior of toxic Cr(VI) in models of aqueous systems for applications in nuclear technology, industrial wastewater treatment, and chemical dosimetry., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Reactions of the hydrated electron with a wide variety of substrates have been found to exhibit unusually similar activation energies in a manner incompatible with Marcus electron transfer theory. Given the fundamental linear response assumption of Marcus theory, one possible explanation for this apparent failure is that the underlying free energy surfaces governing the reactions are not harmonic; i.e., hydrated electron structural fluctuations exhibit non-Gaussian behavior. In this work, we test this hypothesis by using simulations to calculate the hydrated electron vertical detachment energy distribution. We consider both cavity and noncavity models for the hydrated electron, between which the actual hydrated electron behavior is expected to lie. Our results identify a possible origin for non-Gaussian behavior of the hydrated electron but show that it is not of sufficient magnitude to explain the failure of Marcus theory to describe its reactions. Thus, other explanations must be sought.

Reactivity of transients involving Zn + in high-temperature water radiolysis has been studied in the temperature range of 25-300 °C. The reduced monovalent zinc species were generated from an electron transfer process between the hydrated electron and Zn 2+ ions using pulse radiolysis. The Zn + species can subsequently be oxidized by the radiolytically-produced oxidizing species: ˙OH, H 2 O 2 and ˙H. We find that the absorption of monovalent zinc is very sensitive to the pH of the medium. An absorption maximum at 306-311 nm is most pronounced at pH 7 and the signal then decreases in acidic media where the reducing electrons are competitively captured by protons. At pH values higher than 7, hydroxo-forms of Zn 2+ are created and the maximum of the absorption signal begins to shift to the red spectral region. We find that the optical spectrum of Zn + aq cannot be fully explained in terms of a charge-transfer to solvent (CTTS) process, which was previously proposed. Reaction rates of most of the recombination reactions investigated follow the empirical Arrhenius relationship at temperatures up to 200 °C and have been determined at higher temperatures for the first time. A bimolecular disproportionation reaction of Zn + aq is not observed under the conditions investigated.

The lowest band in the charge-transfer-to-solvent ultraviolet absorption spectrum of aqueous chloride ion is studied by experiment and computation. Interestingly, the experiments indicate that at concentrations up to at least 0.25 M, where calculations indicate ion pairing to be significant, there is no notable effect of ionic strength on the spectrum. The experimental spectra are fitted to aid comparison with computations. Classical molecular dynamic simulations are carried out on dilute aqueous Cl-, Na+, and NaCl, producing radial distribution functions in reasonable agreement with experiment and, for NaCl, clear evidence of ion pairing. Clusters are extracted from the simulations for quantum mechanical excited state calculations. Accurate ab initio coupled-cluster benchmark calculations on a small number of representative clusters are carried out and used to identify and validate an efficient protocol based on time-dependent density functional theory. The latter is used to carry out quantum mechanical calculations on thousands of clusters. The resulting computed spectrum is in excellent agreement with experiment for the peak position, with little influence from ion pairing, but is in qualitative disagreement on the width, being only about half as wide. It is concluded that simulation by classical molecular dynamics fails to provide an adequate variety of structures to explain the experimental CTTS spectrum of aqueous Cl-.

We demonstrate a method for measuring the H 2 produced in water from the 10 B(n,α) 7 Li fission reaction. Low energy neutrons from the NIST Center for Neutron Research interact with borate-containing water in a temperature-controlled high pressure cell made from titanium. After exposure for one to several hours, the water is extracted and sparged with argon. H 2 entrained in the sparging gas is sampled with a small mass spectrometer. To determine the neutron exposure, a small amount of sodium is included in the borate solution. The water is collected and 24 Na activation is measured in a counting apparatus on the following day. The G-value for H 2 at room temperature is found to be (1.18 ± 0.10) molecules H 2 /100eV, in good agreement with previous estimates and recent modeling calculations.

The one-electron redox potentials for aqueous metal couples Co 2+/+ and Ni 2+/+ have been investigated by using pulse radiolysis using their reactions with a series of reference compounds to establish the most positive upper limits of E 0 . Experiments with Zn + were also carried out to confirm the characteristic shape of the expected reduction kinetics. Both formate ions and t-BuOH were employed to scavenge ˙OH radicals and ˙H atoms. Kinetics and fitted first and second order reaction rates have been reported for reactions with methyl viologen, fluorescein, Ru(NH 3 ) 6 3+ , Co(en) 3 2+ , Co(sepulcrate) 3+ , Ru(bpy) 3 2+ , Cr(bpy) 3 3+ , and Ni(Me 6 [14]4,11-dieneN 4 ) 2+ . Previous work demonstrated that both Co 2+ and Ni 2+ can be reduced by CO 2 ˙ - radicals, giving a negative E 0 limit of -1.9 V vs. SHE. A definite reaction of Ni + with fluorescein di-anions provides a new upper limit of the Ni 2+/+ couple as -0.906 V vs. SHE. The reaction of Co + with Ru(bpy) 3 2+ has been confirmed, giving E 0 = -1.3 V vs. SHE as a rigorous upper limit of the Co 2+/+ couple. In the case of Co 2+/+ , kinetics were complicated by a self-catalyzed metal clustering phenomenon. Initiation rate constants of this process have also been reported.

To what extent are research results influenced by subjective decisions that scientists make as they design studies? Fifteen research teams independently designed studies to answer five original research questions related to moral judgments, negotiations, and implicit cognition. Participants from 2 separate large samples (total N > 15,000) were then randomly assigned to complete 1 version of each study. Effect sizes varied dramatically across different sets of materials designed to test the same hypothesis: Materials from different teams rendered statistically significant effects in opposite directions for 4 of 5 hypotheses, with the narrowest range in estimates being d = -0.37 to + 0.26. Meta-analysis and a Bayesian perspective on the results revealed overall support for 2 hypotheses and a lack of support for 3 hypotheses. Overall, practically none of the variability in effect sizes was attributable to the skill of the research team in designing materials, whereas considerable variability was attributable to the hypothesis being tested. In a forecasting survey, predictions of other scientists were significantly correlated with study results, both across and within hypotheses. Crowdsourced testing of research hypotheses helps reveal the true consistency of empirical support for a scientific claim. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

People often make tradeoffs between current and future benefits. Some research frameworks suggest that people treat the future self as if it were another person, subordinating future needs to current ones just as they might subordinate others' needs to their own. Although people make similar choices for future selves and others in some contexts, it remains unclear whether these behaviors are governed by the same decision policies. So, we identify and compare the unique influence of four relevant factors (need, deservingness, liking, and similarity) on monetary decisions in both the interpersonal and intrapersonal domains. Do people treat the future self and others similarly? Yes and no. Yes, because the influence of these factors on allocations is similar for both types of targets. No, because monetary allocations to the future self are consistently higher than allocations to others. Although the future self is treated like others in some ways, important differences remain that are not fully captured by this analogy., Competing Interests: Declaration of competing interest None., (Copyright © 2019 Elsevier B.V. All rights reserved.)

When a nonthermal plasma and a liquid form part of the same circuit, the liquid may function as a cathode, in which case electrons are emitted from the liquid into the gas to sustain the plasma. As opposed to solid electrodes, the mechanism of this emission has not been established for a liquid, even though various theories have attempted to explain it via chemical processes in the liquid phase. In this work, we tested the effects of the interfacial chemistry on electron emission from water, including the role of pH as well as the hydroxyl radical, the hydrogen atom, the solvated electron, and the presolvated electron; it was found that none of these species are critical to sustain the plasma. We propose an emission mechanism where electrons, generated from ionized water molecules in the uppermost monolayers of solution, are emitted into the plasma directly from the conduction band of the water.

The radiolytic stability of a series of room-temperature ionic liquids (ILs) composed of bis(trifluoromethylsulfonyl)imide anion (Tf 2 N - ) and triethylammonium, 1-butyl-1-methylpyrrolidinium, trihexyl(tetradecyl)phosphonium, 1-hexyl-3-methylpyridinium, and 1-hexyl-3-methylimidazolium (hmim) cations was studied using spin-trap electron paramagnetic resonance (EPR) spectroscopy with a spin-trap α-(4-pyridyl N -oxide)- N - tert -butylnitrone (POBN). The trapped radical yields were measured as a function of POBN concentration and as a function of radiation dose by double integration of the broad unresolved lines. Well-resolved motionally narrowed EPR spectra for the trapped radicals were obtained by dilution of the ILs with CH 2 Cl 2 after irradiation. The trapped radicals were identified as mainly carbon-centered alkyl and • CF 3 , and their ratio varies greatly across the series of ILs. Expected nitrogen-centered radicals derived from Tf 2 N - were not observed. The hmim liquid proved most interesting because a large part of the trapped radical yield (entirely carbon-centered) grew in over several hours after irradiation. We also discovered a complicated narrow-line stable radical signal in this neat IL with no spin trap added, which grows in over several hours after irradiation and decays over several weeks.

The temperature dependence of the vacuum ultraviolet charge-transfer-to-solvent (CTTS) absorption spectra of aqueous halide and hydroxide ions was measured for the first time up to 380 °C in subcritical and supercritical water. With increasing temperature, absorption spectra are observed to broaden and redshift, much in agreement with previous measurements below 100 °C. These changes are discussed alongside classic cavity models of the solvated species, which tie in the configuration of the adjoining polarized medium and its critical role in light absorption for electronic transitions. The data seemingly confirm the validity of the "diffuse" model pioneered by Platzman and Franck and later revised by Stein and Treinin, which has largely gone untested for nearly 60 years due to lack of experimental data in this extended temperature range. A gradual increase in anion cavity size is inferred as a function of increasing temperature while the enthalpy and entropy of hydration are largely unaffected. The changes in solvation properties are considered in the context of recent studies of the ultraviolet spectroscopy of subcritical and supercritical water and historic studies of the CTTS absorption. The "diffuse" polarizable continuum model succeeds in describing the absorption due to lack of well-defined ion hydration shells for these ions. CTTS spectra for iodide in supercritical water show no energy shift as a function of pressure/density, suggesting dielectric saturation of the I- anion by the adjacent H2O molecules at all experimental pressures/densities.

The partial molar volume of the hydrated electron was investigated with pulse radiolysis and transient absorption by measuring the pressure dependence of the equilibrium constant for e - aq + NH 4 + ⇔ H + NH 3 . At 2 kbar pressure, the equilibrium constant decreases relative to 1 bar by only 6%. Using tabulated molar volumes for ammonia and ammonium, we have the result V̅(e - aq ) - V̅(H) = 11.3 cm 3 /mol at 25 °C, confirming that V̅(e - aq ) is positive and even larger than the hydrophobic H atom. Assuming on the basis of recent molecular dynamics simulations that the molar volume of the H atom is somewhat less than that of H 2 , we estimate V̅(e - aq ) = 26 ± 6 cm 3 /mol. The positive molar volume is consistent with an electron that exists largely in a small solvent void (cavity), ruling out a recent model ( Larsen , R. E. ; Glover , W. J. ; Schwartz , B. J. Science 2010 , 329 , 65 - 69 ) that suggests a noncavity structure with negative molar volume.

We propose that methods from the study of category-based induction can be used to test the descriptive accuracy of theories of moral judgment. We had participants rate the likelihood that a person would engage in a variety of actions, given information about a previous behavior. From these likelihood ratings, we extracted a hierarchical, taxonomic model of how moral violations relate to each other (Study 1). We then tested the descriptive adequacy of this model against an alternative model inspired by Moral Foundations Theory, using classic tasks from induction research (Studies 2a and 2b), and using a measure of confirmation, which accounts for the baseline frequency of these violations (Study 3). Lastly, we conducted focused tests of combinations of violations where the models make differing predictions (Study 4). This research provides new insight into how people represent moral concepts, connecting classic methods from cognitive science with contemporary themes in moral psychology. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The total internal reflection absorption spectroscopy (TIRAS) method presented in this article uses an inexpensive diode laser to detect solvated electrons produced by a low-temperature plasma in contact with an aqueous solution. Solvated electrons are powerful reducing agents, and it has been postulated that they play an important role in the interfacial chemistry between a gaseous plasma or discharge and a conductive liquid. However, due to the high local concentrations of reactive species at the interface, they have a short average lifetime (~1 µs), which makes them extremely difficult to detect. The TIRAS technique uses a unique total internal reflection geometry combined with amplitude-modulated lock-in amplification to distinguish solvated electrons' absorbance signal from other spurious noise sources. This enables the in situ detection of short-lived intermediates in the interfacial region, as opposed to the bulk measurement of stable products in the solution. This approach is especially attractive for the field of plasma electrochemistry, where much of the important chemistry is driven by short-lived free radicals. This experimental method has been used to analyze the reduction of nitrite (NO2 - (aq)), nitrate (NO3 - (aq)), hydrogen peroxide (H2O2(aq)), and dissolved carbon dioxide (CO2(aq)) by plasma-solvated electrons and deduce effective rate constants. Limitations of the method may arise in the presence of unintended parallel reactions, such as air contamination in the plasma, and absorbance measurements may also be hindered by the precipitation of reduced electrochemical products. Overall, the TIRAS method can be a powerful tool for studying the plasma-liquid interface, but its effectiveness depends on the particular system and reaction chemistry under study.

The use of performance enhancing drugs (PEDs) elicits widespread normative opposition, yet little research has investigated what underlies these judgments. We examine this question comprehensively, across 13 studies. We first test the hypothesis that opposition to PED use cannot be fully accounted for by considerations of fairness. We then test the influence of 10 other potential drivers of opposition in an exploratory manner. We find that health risks for the user and rules and laws prohibiting use of anabolic steroids reliably affect normative judgments. Next, we test whether these patterns generalize to a different PED-cognitive-enhancement drugs. Finally, we sketch a framework for understanding these results, borrowing from Social Domain Theory (e.g., Turiel, 1983). We argue that PED use exemplifies a class of violations with properties of moral, conventional, and prudential offenses. This research sheds light on a widespread, but understudied, normative judgment, and illustrates the utility of exploratory methods. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)

The nature and extent of hydrogen bonding in water has been scrutinized for decades, including how it manifests in optical properties. Here we report vacuum ultraviolet absorption spectra for the lowest-lying electronic state of subcritical and supercritical water. For subcritical water, the spectrum redshifts considerably with increasing temperature, demonstrating the gradual breakdown of the hydrogen-bond network. Tuning the density at 381 °C gives insight into the extent of hydrogen bonding in supercritical water. The known gas-phase spectrum, including its vibronic structure, is duplicated in the low-density limit. With increasing density, the spectrum blueshifts and the vibronic structure is quenched as the water monomer becomes electronically perturbed. Fits to the supercritical water spectra demonstrate consistency with dimer/trimer fractions calculated from the water virial equation of state and equilibrium constants. Using the known water dimer interaction potential, we estimate the critical distance between molecules (ca. 4.5 Å) needed to explain the vibronic structure quenching.

Five studies explore how anticipating different types of personal change affects people's perceptions of their own self-continuity. The studies find that improvements are seen as less disruptive to personal continuity than worsening or unspecified change, although this difference varies in magnitude based on the type of feature being considered. Also, people's expectations and desires matter. For example, a negative change is highly disruptive to perceived continuity when people expect improvement and less disruptive when people expect to worsen. The finding that some types of change are consistent with perceptions of self-continuity suggests that the self-concept may include beliefs about personal development., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Personal identity is an important determinant of behavior, yet how people mentally represent their self-concepts and their concepts of other people is not well understood. In the current studies, we examined the age-old question of what makes people who they are. We propose a novel approach to identity that suggests that the answer lies in people's beliefs about how the features of identity (e.g., memories, moral qualities, personality traits) are causally related to each other. We examined the impact of the causal centrality of a feature, a key determinant of the extent to which a feature defines a concept, on judgments of identity continuity. We found support for this approach in three experiments using both measured and manipulated causal centrality. For judgments both of one's self and of others, we found that some features are perceived to be more causally central than others and that changes in such causally central features are believed to be more disruptive to identity.

The solvation structure of a solvated electron in methanol is investigated with ab initio calculations of small anion methanol clusters in a polarized dielectric continuum. We find that the lowest-energy structure in best agreement with experiment, calculated with CCSD, MP2, and B3LYP methods with aug-cc-pvdz basis set, is a tetrahedral arrangement of four methanol molecules with OH bonds oriented toward the center. The optimum distance from the tetrahedron center to the hydroxyl protons is ∼1.8 Å, significantly smaller than previous estimates. We are able to reproduce experimental radius of gyration Rg (deduced from optical absorption), vertical detachment energy, and resonance Raman frequencies. The electron paramagnetic resonance g-factor shift is qualitatively reproduced using density functional theory.

Relative diffusion coefficients were determined in water for the D, H, and Mu isotopes of atomic hydrogen by measuring their diffusion-limited spin-exchange rate constants with Ni(2+) as a function of temperature. H and D atoms were generated by pulse radiolysis of water and measured by time-resolved pulsed EPR. Mu atoms are detected by muonium spin resonance. To isolate the atomic mass effect from solvent isotope effect, we measured all three spin-exchange rates in 90% D2O. The diffusion depends on the atomic mass, demonstrating breakdown of Stokes-Einstein behavior. The diffusion can be understood using a combination of water "cavity diffusion" and "hopping" mechanisms, as has been proposed in the literature. The H/D isotope effect agrees with previous modeling using ring polymer molecular dynamics. The "quantum swelling" effect on muonium due to its larger de Broglie wavelength does not seem to slow its "hopping" diffusion as much as predicted in previous work. Quantum effects of both the atom mass and the water librations have been modeled using RPMD and a qTIP4P/f quantized flexible water model. These results suggest that the muonium diffusion is very sensitive to the Mu versus water potential used.

Molecular hydrogen is a primary product of the interaction of low-LET (γ, β) radiation with water, and previous measurements have shown that its initial yield increases at elevated temperature. This has been the subject of controversy because more atomic H and (e(-))aq free radicals escape recombination at elevated temperature, and the corresponding production of H2 should decrease. Room temperature experiments have demonstrated that a large fraction of H2 also comes from early physicochemical processes (presumably electron-hole charge recombination and/or dissociative electron attachment), which can be suppressed by scavenging presolvated electrons. In the present work we extend these scavenging measurements up to 350 °C to investigate why the H2 yield increases. We find that most of the H2 yield increase is due to the "presolvation" processes. Relatively small changes in the scavenging efficiency vs LET, and a significant effect of temperature depending on the (positive or negative) charge of the scavenger, indicate that the presolvation H2 is dominated by electron-hole charge recombination rather than dissociative electron attachment at all temperatures.

Reactions of the hydrated electron with divalent aqueous transition-metal ions, Cd(2+), Zn(2+), Ni(2+), Cu(2+), Co(2+), Fe(2+), and Mn(2+), were studied using a pulse radiolysis technique. The kinetics study was carried out at a constant pressure of 120 bar with temperatures up to 300 °C. The rate constants at room temperature agree with those reported in the literature. The reaction of Cd(2+) is approximately diffusion-limited, but none of the first-row transition-metal ion reactions are diffusion-controlled at any temperature studied. The activation energies obtained from the Arrhenius plots are in the range 14.5-40.6 kJ/mol. Pre-exponential factors are quite large, between 1 × 10(13) and 7 × 10(15) M(-1) s(-1). There appears to be a large degree of entropy-enthalpy compensation in the activation of Zn(2+), Ni(2+), Co(2+), and Cu(2+), as the larger pre-exponential factors strongly correlate with higher activation energy. Saturation of the ionic strength effect suggests that these reactions could be long-range nonadiabatic electron "jumps", but Marcus theory is incompatible with direct formation of ground state (M(+))aq ions. A self-consistent explanation is that electron transfer occurs to excited states derived from the metal 4s orbitals. The ionic strength effect in the Mn(2+) and Fe(2+) reactions suggests that these proceed by short-range adiabatic electron attachment involving breakdown of the water coordination shell.

Since its discovery over 50 years ago, the "structure" and properties of the hydrated electron have been a subject for wonderment and also fierce debate. In the present work we seriously explore a minimal model for the aqueous electron, consisting of a small water anion cluster embedded in a polarized continuum, using several levels of ab initio calculation and basis set. The minimum energy "zero Kelvin" structure found for any 4-water (or larger) anion cluster, at any post-Hartree–Fock theory level, is very similar to a recently reported embedded-DFT-in-classical-water-MD simulation (Uhlig, Marsalek, and Jungwirth, J. Phys. Chem. Lett. 2012, 3, 3071−3075), with four OH bonds oriented toward the maximum charge density in a small central "void". The minimum calculation with just four water molecules does a remarkably good job of reproducing the resonance Raman properties, the radius of gyration derived from the optical spectrum, the vertical detachment energy, and the hydration free energy. For the first time we also successfully calculate the EPR g-factor and (low temperature ice) hyperfine couplings. The simple tetrahedral anion cluster model conforms very well to experiment, suggesting it does in fact represent the dominant structural motif of the hydrated electron.

Solvated electrons are typically generated by radiolysis or photoionization of solutes. While plasmas containing free electrons have been brought into contact with liquids in studies dating back centuries, there has been little evidence that electrons are solvated by this approach. Here we report direct measurements of solvated electrons generated by an atmospheric-pressure plasma in contact with the surface of an aqueous solution. The electrons are measured by their optical absorbance using a total internal reflection geometry. The measured absorption spectrum is unexpectedly blue shifted, which is potentially due to the intense electric field in the interfacial Debye layer. We estimate an average penetration depth of 2.5 ± 1.0 nm, indicating that the electrons fully solvate before reacting through second-order recombination. Reactions with various electron scavengers including H(+), NO2(-), NO3(-) and H2O2 show that the kinetics are similar, but not identical, to those for solvated electrons formed in bulk water by radiolysis.

The self-recombination reaction of (•)CH2OH radicals in neutral aqueous solution has been studied at temperatures up to 300 °C at a pressure of 220 bar using pulse radiolysis and transient absorption. (•)CH2OH species decay by second-order kinetics independent of the applied dose, with a rate constant at 22 °C of 2k = 1.4 ± 0.1 × 10(9) M(-1) s(-1). The recombination follows Arrhenius behavior with the activation energy (E(a)) 12.7 ± 0.9 kJ/mol and pre-exponential factor of 1.9 ± 0.4 × 10(11) M(-1) s(-1). The overall recombination is significantly slower than the diffusion limit at elevated temperature, meaning that both disproportionation and dimerization channels have significant activation barriers. Ab initio calculations support the inference that the dimerization channel has no energy barrier, but has a large negative activation entropy barrier. The disproportionation channel (giving aqueous formaldehyde) almost certainly involves one or more specific water molecules to lower its activation energy relative to the gas phase.

We describe what can be gained from connecting cognition and consumer choice by discussing two contexts ripe for interaction between the two fields. The first-context effects on choice-has already been addressed by cognitive science yielding insights about cognitive process but there is promise for more interaction. The second is learning and representation in choice where relevant theories in cognitive science could be informed by consumer choice, and in return, could pose and answer new questions. We conclude by discussing how these two fields of research stand to benefit from more interaction, citing examples of how interfaces of cognitive science with other fields have been illuminating for theories of cognition., (Copyright © 2014 Elsevier B.V. All rights reserved.)

This paper examines people's reasoning about identity continuity (i.e., how people decide that a particular object is the same object over time) and its relation to previous research on how people value one-of-a-kind artifacts, such as artwork. We propose that judgments about the continuity of artworks are related to judgments about the continuity of individual persons because art objects are seen as physical extensions of their creators. We report a reanalysis of previous data and the results of two new empirical studies that test this hypothesis. The first study demonstrates that the mere categorization of an object as "art" versus "a tool" changes people's intuitions about the persistence of those objects over time. In a second study, we examine some conditions that may lead artworks to be thought of as different from other artifacts. These observations inform both current understanding of what makes some objects one-of-a-kind as well as broader questions regarding how people intuitively think about the persistence of human agents., (Copyright © 2014 Cognitive Science Society, Inc.)

In four studies, we show that people who anticipate more personal change over time give more to others. We measure and manipulate participants' beliefs in the persistence of the defining psychological features of a person (e.g., his or her beliefs, values, and life goals) and measure generosity, finding support for the hypothesis in three studies using incentive-compatible charitable donation decisions and one involving hypothetical choices about sharing with loved ones., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Preimplantation genetic diagnosis (PGD) to create a healthy donor for a sibling's hematopoetic stem cell transplantation for a child with Fanconi Anemia (FA) was first reported in 2001. Yet we know little about the experiences of parents who have encountered decision making surrounding PGD and human leukocyte antigen (HLA)-typing. The first aim of this study was to understand parents' awareness, perceptions and beliefs about reproductive decision-making including emotional, cognitive, moral dimensions as well as regret surrounding the use of this technology. The second aim was to describe the experiences and rationale of parents of children with a single gene disorder regarding the factors that influenced their decision making surrounding the use of natural pregnancy and/or PGD and HLA-typing. Parents from two national FA support networks in the US and Canada responded to an emailed survey about reproductive decision making and outcomes surrounding natural pregnancy and PGD and HLA-typing. Descriptive statistics and Pearson's Chi-Square tests were used to describe and compare data. Our results indicate that the most important factors in the PGD decision making process were the health of the child and cognitive appraisals followed by emotional responses and then moral judgments. A significant difference was noted in parents considering natural pregnancy before and after 2001 (p = 0.01). Unexpected findings were that less than 35 % of parents were offered PGD by any health care professional and only 70 % were aware PGD with HLA-typing was a reproductive option. Our research suggests that the option of PGD and HLA-typing may influence parents' reproductive decision making choices.