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Youth suicide is increasing in the United States, with deaths among younger people of color driving this upward trend. For more than four decades, American Indian and Alaska Native (AIAN) communities have suffered disproportionate rates of youth suicide and years of productive life lost compared to other U.S. Races. The National Institute of Mental Health (NIMH) recently funded three regional Collaborative Hubs to carry out suicide prevention research, practice, and policy development with AIAN communities in Alaska and rural and urban areas of the Southwestern United States. The Hub partnerships are supporting a diverse array of tribally-driven studies, approaches, and policies with immediate value for increasing empirically driven public health strategies to address youth suicide. We discuss unique features of the cross-Hub work, including: (a) long-standing Community-Based Participatory Research processes that led to the Hubs' innovative designs and novel approaches to suicide prevention and evaluation, (b) comprehensive ecological theoretical approaches that contextualize individual risk and protective factors in multilevel social contexts; (c) unique task-shifting and systems of care approaches to increase reach and impact on youth suicide in low-resource settings; and (d) prioritization of strengths-based approaches. The work of the Collaborative Hubs for AIAN youth suicide prevention is generating specific and substantive implications for practice, policy, and research presented in this article at a time when youth suicide prevention is a dire national priority. Approaches also have relevance for historically marginalized communities worldwide. [ABSTRACT FROM AUTHOR]

Photoionization of the free and confined Mg (Mg@C60) have been calculated in the vicinity of the inner-shell 2p thresholds using R -matrix at the Breitâ€"Pauli R -matrix level with a particular emphasis on the various resonance series leading up to the two lowest inner-shell thresholds and the changes resulting from the confinement. For free Mg, the calculated resonance positions agree well with NIST values, and a number of new resonances are identified. For confined Mg, the calculation was done for various depths of the confining potential well in order to follow the trajectories of the resonances as a function of well depth. The results for the well depth corresponding to Mg@C60 showed that most of the resonances moved to higher photon energy, as a result of the confinement, but a few moved to lower energies. This phenomenology was found to result from the fact that the 3p, 3d and 4s excitations are trapped by the confining potential well, while the higher excitations were not. [ABSTRACT FROM AUTHOR]

Calculations of the photoionization cross sections of the ground states of the superheavy atoms No (Z = 102), Cn (Z = 112) and Og (Z = 118) have been performed using fully relativistic methodologies. The photoionization cross sections are dominated by interchannel coupling, in all cases, over a broad energy range including both outer and inner shells. [ABSTRACT FROM AUTHOR]

The effect of inner-shell photodetachment channels on outer-shell photodetachment is investigated using the R-matrix method. The simplest multishell closed-shell negative ion, Li−, is examined near the 1s detachment threshold and the results show that the interchannel coupling significantly alters the shapes and magnitudes of the valence photodetachment cross sections in this energy region. [ABSTRACT FROM AUTHOR]

A semiempirical model of single differential cross sections (SDCS) for ionization of water vapor by fast electrons and bare ions is presented. At low secondary-electron energy, the model is based on an asymptotic expansion of the first Born approximation with coefficients, that are independent of projectile properties, evaluated from experimental photoabsorption and proton-impact ionization data. As the secondary-electron energy increases, the model converges to a binary-encounter approximation. Comparisons with measured differential, total, and dissociative cross sections for ionization of water by fast electrons are used to test the model. For primary electrons with energy greater than about 500 eV, agreement with these data is generally within experimental uncertainty; however, some discrepancies of uncertain origin exist. [ABSTRACT FROM AUTHOR]

Summary: Objective: The objective of this study was to examine patient–provider relationships among American Indians and Alaska Native (AI/AN) patients by examining associations between patient activation, perceived provider weight bias and working alliance. Patient activation is generally defined as having the knowledge, skills and confidence to manage one's health. Methods: Among a sample of 87 AI/AN adults presenting for general medical care at an urban clinic in the north‐west region of the USA, ordinary least squares regression analysis was completed to examine associations. Results: Better working alliance scores were associated with increased patient activation, while perceived provider weight bias was associated with reduced patient activation. In addition, those with class II obesity had decreased patient activation. Conclusion: These findings point to the importance of a positive patient–provider relationship in AI/ANs. Optimal patient engagement and subsequent health outcomes warrant additional consideration of patients' perceptions of provider weight bias within the context of health promotion and interventions. [ABSTRACT FROM AUTHOR]

Land system science axiomatically addresses social–environmental systems by integrating the dynamics of land uses (social) and land covers (environment), invariably including the use of remote sensing data and often, spatially explicit models of land change. This kind of research is illustrated through the Southern Yucatán Peninsular Region project (1997–2008) aimed at understanding, predicting, and projecting spatially explicit land change in a region with juxtaposed land uses-agriculture and a biosphere reserve. The successes of the project, its contributions to contemporary land system science, and the organizational mechanisms that fostered the research are identified as well as various corrections, which if applied, may have refined and extended the project's goals. Overall, the project demonstrates the kind of integrated research required to advance understanding of a social-environment system and the team-based methods used in the process. [ABSTRACT FROM AUTHOR]

We report studies of photoelectron angular distribution and cross-section for photoionization of xenon 5s electrons using the relativistic multiconfiguration Tamm–Dancoff (MCTD) approximation. We find that MCTD provides a significantly improved agreement with experiment, compared to some of the other relativistic many body approximations such as the relativistic random phase approximation and the relativistic random phase approximation with relaxation, over the entire photon energy region bracketing the near-threshold 5s Cooper minimum, from the 5s threshold up to about 70 eV. The MCTD results in the length form are in much better agreement with the experiment than those in the velocity form, suggesting residual correlations that must be of importance. [ABSTRACT FROM AUTHOR]

The 3d core level photoemission of metallic Ag and In was measured over a wide energy range including the 2p ionization thresholds. The intensities (photoionization cross sections) of the 3d5/2 and 3d3/2 lines were observed to modulate significantly with photon energy, both absolute and relative, and this is most pronounced in the vicinity of the 2p thresholds, i.e., at photon energies about an order of magnitude above the 3d thresholds. Calculations based on the relativistic-random-phase approximation show that this effect is due to interchannel coupling of the 3d photoionization channels with the 2p channels affecting the cross section over a wide range of energies. It is argued that this is a general phenomenon in high-energy photoionization throughout the periodic table. [ABSTRACT FROM AUTHOR]

An analytical formula is developed to accurately represent the photoabsorption cross section of O I for all energies of interest in X-ray spectral modeling. In the vicinity of the K edge, a Rydberg series expression is used to fit R-matrix results, including important orbital relaxation effects, that accurately predict the absorption oscillator strengths below threshold and merge consistently and continuously to the above-threshold cross section. Further, minor adjustments are made to the threshold energies in order to reliably align the atomic Rydberg resonances after consideration of both experimental and observed line positions. At energies far below or above the K-edge region, the formulation is based on both outer- and inner-shell direct photoionization, including significant shake-up and shake-off processes that result in photoionization-excitation and double-photoionization contributions to the total cross section. The ultimate purpose for developing a definitive model for oxygen absorption is to resolve standing discrepancies between the astronomically observed and laboratory-measured line positions, and between the inferred atomic and molecular oxygen abundances in the interstellar medium from XSTAR and SPEX spectral models. [ABSTRACT FROM AUTHOR]

The photoionization of Ba 5s in the high-energy Cooper minimum region has been investigated using the relativistic-random-phase approximation and the relativistic-randomphase approximation with relaxation. Comparison with recent experiment shows good agreement for the total cross section, but only qualitative agreement for the photoelectron angular distribution asymmetry parameter, ß. The disagreement was traced to the omission of photoionization-plus-excitation channels arising from the 4d subshell. [ABSTRACT FROM AUTHOR]

The combined effects of interchannel coupling, relativistic interactions and endohedral confinement on the photoionization of atomic Kr are studied. The confinement of the Kr atom placed at the centre of the C60 cage is modelled by placing the atom inside an annular spherical potential. Cross sections for the photoionization and angular distribution of photoelectrons from the 4p, 4s, 3d and 3p subshells are reported within the framework of the relativistic-random-phase approximation. [ABSTRACT FROM AUTHOR]

The photoabsorption by an electron bound by a two-centre potential has been investigated within the framework of the zero-range potential model. Expressions for total photoabsorption cross sections and for the photoelectron angular distributions have been derived for fixed-in-space and randomly oriented targets. The analytical formulae for gerade and ungerade molecular states have been used to analyse separately the molecular effects due to the two-centre ground state of quasi-molecule and diffraction effects that are connected with the spherical waves in the molecular continuum. It is shown that the interference of these waves significantly influences the magnitude of the cross sections near threshold but does not significantly distort the shape of the photoelectron angular distribution and it depends rather weakly on the character of the forces acting between the electron and molecular residue: Coulomb forces for neutral molecular photoionization or the short-range forces in the case of photodetachment of molecular negative ions. It is shown that despite the fact that the photoionization of diatomic molecules is reminiscent of Young's double-slit experiment, the similarity between these processes has been grossly exaggerated. This is confirmed by comparing the results of the classical interference of an electron scattered by two spatially separated centres with molecular photoelectron angular distributions [ABSTRACT FROM AUTHOR]

The relativistic-random-phase approximation (RRPA) methodology, developed by Walter Johnson and his collaborators, has been used extensively over the past three decades to calculate various aspects of the atomic photoionization process, cross sections, and branching ratios along with dipole and nondipole contributions to the photoelectron angular distribution. In this paper, some of the progress made in our understanding of the photoionization process as a result of RRPA calculations is reviewed.PACS No.: 32.80.Fb [ABSTRACT FROM AUTHOR]

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For the complex systems modeller, uncertainty is ever-present. While uncertainty cannot be eliminated, we suggest that formally incorporating an assessment of uncertainty into our models can provide great benefits. Sources of uncertainty arise from the model itself, theoretical flaws, design flaws, and logical errors. Management of uncertainty and error in complex systems models calls for a structure for uncertainty identification and a clarification of terminology. In this paper, we define complex systems and place complex systems models into a common typology leading to the introduction of complex systems specific issues of error and uncertainty. We provide examples of complex system models of land use change with foci on errors and uncertainty and finally discuss the role of data in building complex systems models. [ABSTRACT FROM AUTHOR]

This paper examines the use of evolutionary programming in agent‐based modelling to implement the theory of bounded rationality. Evolutionary programming, which draws on Darwinian analogues of computing to create software programs, is a readily accepted means for solving complex computational problems. Evolutionary programming is also increasingly used to develop problem‐solving strategies in accordance with bounded rationality, which addresses features of human decision‐making such as cognitive limits, learning, and innovation. There remain many unanswered methodological and conceptual questions about the linkages between bounded rationality and evolutionary programming. This paper reports on how changing parameters in one variant of evolutionary programming, genetic programming, affects the representation of bounded rationality in software agents. Of particular interest are: the ability of agents to solve problems; limits to the complexity of agent strategies; the computational resources with which agents create, maintain, or expand strategies; and the extent to which agents balance exploration of new strategies and exploitation of old strategies. [ABSTRACT FROM AUTHOR]