Effects of the Nearest-Neighbour Coulomb Interactions on the Ground State of the Periodic Anderson Model

The magnetic and non-magnetic ground states of the periodic Anderson model with Coulomb interaction between $f$-electrons on the nearest-neighbour(NN) sites are investigated using a variational method, which gives exact calculation of the expectation values in the limit of infinite dimensions. It is shown that for a critical value of NN Coulomb interactions the magnetic ground state of the periodic Anderson model in the Kondo regime is unstable. Factors in terms of the physical processes responsible for instability of the magnetic ground state are also discussed. Our study indicates the importance of the NN Coulomb interactions for correlated two band models.Comment: RevTeX, 6 pages, 5 figures, to appear in Phys. Rev.

Exploring media-induced secondary trauma during COVID-19: A global perspective

Aims: Given the risk of developing vicarious trauma through news media has increased during the pandemic, we explored risk factors associated with media induced secondary trauma, and its behavioral and psychological implications. Methods: An international study (N = 1066), with a diverse sample, was administered in July 2020. We used standardized and validated questionnaires to measure news consumption, media-related trauma, compliance, and paranoia. Results: Greater frequency of news consumption, accessing news via social media and WHO, and believing in conspiracy theories increased likelihood of developing media-induced secondary trauma. News related trauma was associated with greater compliance with safety measures and increased paranoid ideation. Media-trauma however exhibited a greater association with paranoia than compliance. Conclusion: Findings highlight the need to facilitate a collaborative intervention, with public, media houses, health safety officials, and social scientists to have a deeper understanding of potential psychological costs of news consumption patterns

Cooperating Agents for 3D Scientific Data Interpretation

Many organizations collect vast quantities of three-dimensional (3-D) scientific data in volumetric form for a range of purposes, including resource exploration, market forecasting, and process modelling. Traditionally, these data have been interpreted by human experts with only minimal software assistance. However, such manual interpretation is a painstakingly slow and tedious process. Moreover, since interpretation involves subjective judgements and each interpreter has different scientific knowledge and experience, formulation of an effective interpretation often requires the cooperation of numerous such experts. Hence, there is a pressing need for a software system in which individual interpretations can be generated automatically and then refined through the use of cooperative reasoning and information sharing. To this end, a prototype system, SurfaceMapper, has been developed in which a community of cooperating software agents automatically locate and display interpretations in a volume of 3-D scientific data. The challenges and experiences in designing and building such a system are discussed. Particular emphasis is given to the agents' interactions and an empirical evaluation of the effectiveness of different cooperation strategies is presented

Just wrong? Or just WEIRD? Investigating the prevalence of moral dumbfounding in non-Western samples

Moral dumbfounding is the phenomenon that is observed when people defend a moral judgement even though they cannot provide a reason for this judgement. Dumbfounded responding may include admitting to not having reasons, or the use of unsupported declarations (e.g., “It’s just wrong”) as justification for a judgement. Published evidence for dumbfounding has drawn exclusively on samples of WEIRD backgrounds (Western, educated, industrialised, rich, and democratic), and it remains unclear whether the phenomenon is generalilsable to other populations. In three studies we apply a standardised moral dumbfounding task, and show evidence for moral dumbfounding in a Chinese sample (Study 1), an Indian sample (Study 2), and a mixed sample primarily from North Africa and the Middle East (MENA region, Study 3)

Sequence learning under uncertainty in children: self-reflection vs. self-assertion

We know that stochastic feedback impairs children's associative stimulus-response (S-R) learning (Crone et al., 2004a; Eppinger et al., 2009), but the impact of stochastic feedback on sequence learning that involves deductive reasoning has not been not tested so far. In the current study, 8- to 11-year-old children (N = 171) learned a sequence of four left and right button presses, LLRR, RRLL, LRLR, RLRL, LRRL, and RLLR, which needed to be deduced from feedback because no directional cues were given. One group of children experienced consistent feedback only (deterministic feedback, 100% correct). In this condition, green feedback on the screen indicated that the children had been right when they were right, and red feedback indicated that the children had been wrong when they were wrong. Another group of children experienced inconsistent feedback (stochastic feedback, 85% correct, 15% false), where in some trials, green feedback on the screen could signal that children were right when in fact they were wrong, and red feedback could indicate that they were wrong when in fact they had been right. Independently of age, children's sequence learning in the stochastic condition was initially much lower than in the deterministic condition, but increased gradually and improved with practice. Responses toward positive vs. negative feedback varied with age. Children were increasingly able to understand that they could have been wrong when feedback indicated they were right (self-reflection), but they remained unable to understand that they could have been right when feedback indicated they were wrong (self-assertion)

Magnetic properties of polypyrrole - coated iron oxide nanoparticles

Iron oxide nanoparticles were prepared by sol -gel process. Insitu polymerization of pyrrole monomer in the presence of oxygen in iron oxide ethanol suspension resulted in a iron oxide - polypyrrole nanocomposite. The structure and magnetic properties were investigated for varying pyrrole concentrations. The presence of the gamma - iron oxide phase and polypyrrole were confirmed by XRD and FTIR respectively. Agglomeration was found to be comparatively much reduced for the coated samples, as shown by TEM. AC susceptibility measurements confirmed the superparamagnetic behaviour. Numerical simulations performed for an interacting model system are performed to estimate the anisotropy and compare favourably with experimental results.Comment: 11 pages,8 figure

Chemotherapy-related complications in the kidneys and collecting system: an imaging perspective

Nephrotoxicity is a common adverse effect of many chemotherapeutic agents. The agents most commonly associated with chemotherapy-associated nephrotoxicity are methotrexate, semustine, streptozocin, mithramycin, and cisplatin. Certain chemotherapeutic agents have adverse effects on the kidneys and urothelium that can be visualized radiographically, including cystic change, interstitial nephritis, papillary necrosis, urothelial changes, haemorrhagic cystitis, acute tubular necrosis, and infarction. This review focuses on imaging features identifying complications of chemotherapy in the kidneys and collecting system and provides didactic cases to alert referring clinicians

Giant Anomalous Hall Conductivity in the Itinerant Ferromagnet LaCrSb₃ and the Effect of f-Electrons

Itinerant ferromagnets constitute an important class of materials wherein spin polarization can affect the electric transport properties in nontrivial ways. One such phenomenon is anomalous Hall effect which depends on the details of the band structure such as the amount of band crossings in the valence band of the ferromagnet. Here, extraordinary anomalous Hall effect is found in an itinerant ferromagnetic metal LaCrSb3. The rather 2D nature of the magnetic subunit imparts large anisotropic anomalous Hall conductivity of 1250 Ω−1 cm−1 at 2 K. The investigations suggest that a strong Berry curvature by abundant momentum-space crossings and narrow energy-gap openings are the primary sources of the anomalous Hall conductivity. An important observation is the existence of quasi-dispersionless bands in LaCrSb3 which is now known to increase the anomalous Hall conductivity. After introducing f-electrons, anomalous Hall conductivity experiences more than twofold increase and reaches 2900 Ω−1 cm−1 in NdCrSb3. © 2021 The Authors. Advanced Quantum Technologies published by Wiley-VCH Gmb

Feasibility of an Assessment Tool as a Data-Driven Approach to Reducing Racial Bias in Biomedical Publications.

The editorial independence of biomedical journals allows flexibility to meet a wide range of research interests. However, it also is a barrier for coordination between journals to solve challenging issues such as racial bias in the scientific literature. A standardized tool to screen for racial bias could prevent the publication of racially biased papers. Biomedical journals would maintain editorial autonomy while still allowing comparable data to be collected and analyzed across journals. A racially diverse research team carried out a three-phase study to generate and test a racial bias assessment tool for biomedical research. Phase 1, an in-depth, structured literature search to identify recommendations, found near complete agreement in the literature on addressing race in biomedical research. Phase 2, construction of a framework from those recommendations, provides the major innovation of this paper. The framework includes three dimensions of race: 1) context, 2) tone and terminology, and 3) analysis, which are the basis for the Race Equity Vetting Instrument for Editorial Workflow (REVIEW) tool. Phase 3, pilot testing the assessment tool, showed that the REVIEW tool was effective at flagging multiple concerns in widely criticized articles. This study demonstrates the feasibility of the proposed REVIEW tool to reduce racial bias in research. Next steps include testing this tool on a broader sample of biomedical research to determine how the tool performs on more subtle examples of racial bias. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10916-021-01777-w