Phonon spectral function for an interacting electron-phonon system

Using exact diagonalzation techniques, we study a model of interacting electrons and phonons. The spectral width of the phonons is found to be reduced as the Coulomb interaction U is increased. For a system with two modes per site, we find a transfer of coupling strength from the upper to the lower mode. This transfer is reduced as U is increased. These results give a qualitative explanation of differences between Raman and photoemission estimates of the electron-phonon coupling constants for A3C60 (A= K, Rb).Comment: 4 pages, RevTeX, 2 eps figur

An Analysis of Distributed Leadership Implementation In Schools

Many policymakers have sought greater levels of success in schools by implementing more distributive models of leadership, yet many have not achieved desired outcomes. This grounded theory study uncovers what happens within a school organization as it moves from a traditional leadership model to a district mandated distributive leadership model.https://scholarworks.waldenu.edu/archivedposters/1002/thumbnail.jp

Functional Altruism Among Agreeable and Narcissistic Donors: Evidence from Crowdsourced Fundraisers

Given the increasing popularity of crowdsourced fundraisers, understanding how characteristics of funding initiatives and donors influence donations has critical real-world implications. Across two studies, we identified potential situational factors most conducive to successful crowdsourcing while also determining whether individual differences in various personality factors predicted differing levels of donation. Participants in Study 1 (MAge = 19.99; 309 women, 75 men) viewed descriptions that manipulated donation type (organizer donation, anonymous donation, no donation) and type of fundraiser (self-organized, other-organized), and reported their willingness to donate to an individual’s medical treatment and completed inventories assessing Big Five personality traits. In Study 2 participants (MAge = 20.22; 322 women, 102 men) viewed vignettes describing fundraisers for an individual’s vacation fun and completed inventories assessing participantslevels of narcissism using the Pathological Narcissism Inventory. Higher agreeableness in men predicted heightened donation interest, regardless of type of cause, particularly when someone else has already donated (Study 1). Unexpectedly, narcissistic men and women both reported heightened donation interest (Study 2). We frame these findings through a framework assessing the adaptive utility of altruism as a function of personality in modern donation contexts

Zinc sulfide as a solid phase additive for improving the processing characteristics of ferrihydrite residues

The effect of ZnS powders as additives for improving the physical and chemical properties of ferrihydrite residues has been studied in both kinetic and batch experiments. Four ZnS samples were compared: two industrial ZnS concentrates, high purity ZnS pieces, and a sample of synthetic ZnS nanoparticles. The industrial ZnS concentrates were found to be the most effective for promoting the transformation of ferrihydrite to hematite, and this effect was found to be due to their lower surface charge at pH 3, which promotes formation of mixed ZnS/ferrihydrite aggregates. For the high purity ZnS samples, aggregation was not favoured, and only goethite formation was promoted. The effect of particle size of the ZnS additive was also studied, and it was found that samples of smaller average particle size were more effective in promoting phase transformation. Measurement of filtration times and moisture content of ferrihydrite residues precipitated in the presence of ZnS showed only minor improvement in physical handling and indicated that better control of surface properties of the additive would be needed to optimise its effect on phase transformation

Functional altruism among agreeable and narcissistic donors: Evidence from crowdsourced fundraisers

Given the increasing popularity of crowdsourced fundraisers, understanding how characteristics of funding initiatives and donors influence donations has critical real-world implications. Across two studies, we identified potential situational factors most conducive to successful crowdsourcing while also determining whether individual differences in various personality factors predicted differing levels of donation. Participants in Study 1 (MAge = 19.99; 309 women, 75 men) viewed descriptions that manipulated donation type (organizer donation, anonymous donation, no donation) and type of fundraiser (self-organized, other-organized), and reported their willingness to donate to an individual’s medical treatment and completed inventories assessing Big Five personality traits. In Study 2 participants (MAge = 20.22; 322 women, 102 men) viewed vignettes describing fundraisers for an individual’s vacation fun and completed inventories assessing participants levels of narcissism using the Pathological Narcissism Inventory. Higher agreeableness in men predicted heightened donation interest, regardless of type of cause, particularly when someone else has already donated (Study 1). Unexpectedly, narcissistic men and women both reported heightened donation interest (Study 2). We frame these findings through a framework assessing the adaptive utility of altruism as a function of personality in modern donation contexts

Just don\u27t call it boot camp : Implementing intensive dissertation writing experiences

This roundtable presentation explored intensive writing programs for dissertation writers conducted at two R1 institutions. Evaluations indicated the programs encouraged dissertation progress, provided relational support, and taught skills. The materials here share contextual and curricular information and discuss aspects like group dynamics and timing that can affect program success

Tamoxifen may prevent both ER+ and ER- breast cancers and select for ER- carcinogenesis: an alternative hypothesis

Introduction: Breast Cancer Prevention Trial (BCPT) and Multiple Outcomes of Raloxifene (MORE) data have been interpreted to indicate that tamoxifen reduces the risk of ER+ but not ER- breast carcinogenesis. We explored whether these data also support an alternative hypothesis, that tamoxifen influences the natural history of both ER+ and ER- cancers, that it may be equally effective in abrogating or delaying ER- and ER+ carcinogenesis, and place selection pressure, in some cases, for the outgrowth of ER- cancers. Methods: BCPT and MORE data were used to investigate whether: first, tamoxifen could reduce equally the emergence of ER- and ER+ tumors; and second, tamoxifen could select a fraction of emerging ER+ cancers and promote their transformation to ER- cancers. Assuming that some proportion, Z, of ER+ tumors becomes ER- after tamoxifen exposure and that the risk reduction for both ER- and ER+ tumors is equal, we solved for both the transformation rate and the risk reduction rate. Results: If tamoxifen equally reduces the incidence of ER+ and ER- tumors by 60%, the BCPT results are achieved with a transformation of approximately Z = 20% of ER+ to ER- tumors. Validation with MORE data using an equal risk reduction of 60% associated with tamoxifen produces an almost identical transformation rate Z of 23%. Conclusion: Data support an alternative hypothesis that tamoxifen may promote ER- carcinogenesis from a precursor lesion that would otherwise have developed as ER+ without tamoxifen selection

Exploring Relationship Description: A Report from the Describing Relationships Workshop, Simmons College, February 2018

Archivists have included relationship information as a component of contextual and content description; however, they have not been called on to formalize that information. Rather, relationships have been identified and defined through informal narrative contexts, and depend on the archivist’s interpretative work and determination. Additionally, descriptive standards provide little guidance on the explicit description of relationships. To begin to address these issues, a group of archivists gathered in Boston to explore the challenges and opportunities in describing relationships. This paper serves as an account of that workshop from two perspectives: first, it documents the results of the day\u27s discussions and provides some preliminary recommendations, and second, it provides an account and evaluation of the strategy of a local, face-to-face event to explore the inherently complex and interpretive activity of the description of relationships