Fractional charges in pyrochlore lattices

A pyrochlore lattice is considered where the average electron number of electrons per site is half--integer, concentrating on the case of exactly half an electron per site. Strong on-site repulsions are assumed, so that all sites are either empty or singly occupied. Where there are in addition strong nearest--neighbour repulsions, a tetrahedron rule comes into effect, as previously suggested for magnetite. We show that in this case, there exist excitations with fractional charge (+/-) e/2. These are intimately connected with the high degeneracy of the ground state in the absence of kinetic energy terms. When an additional electron is inserted into the system, it decays into two point like excitations with charge -e/2, connected by a Heisenberg spin chain which carries the electron's spin.Comment: 10 pages, 4 eps figures. To appear in Decemeber issue of Annalen der Physi

Penerapan Model Pembelajaran Kooperatif Tipe Make A Match untuk Meningkatkan Motivasi Belajar Siswa pada Mata Pelajaran IPS Siswa Kelas Viii.d SMP Negeri 1 Simpang Kanan

This study aims to increase students' motivation in social studies class of VIII. D SMPN 1 Simpang Kanan, Rokan Hilir through the implementation of learning model of Make A Match on the subject matter even semester in the academic year 2015/2016. The subjects of this study were 20 students consisting of 10 male students and 10 female students. From the research activity of teacher has increased in the first cycle obtained a score of 70.83% both categories, the percentage increased to 95.83% with the category very well. Activities of students in the first cycle only get a percentage 71.67% both categories, increased in the second cycle to a percentage of 86.67% with a good category. Student's motivation is also seen to rise, it is evident from the percentage of student motivation in the first cycle that only earn a percentage of 75.00% in both categories, the percentage increased to 83.75% in both categories. According to the results of the data analysis and discussion of the implementation of this study can be concluded that the use of learning model Make A Match with media cards can increase students' motivation in social studies class VIII D SMPN 1 Simpang Kanan, Simpang Kanan Rokan Hilir in the academic year 2015/2016

Supporting the active learning of collaborative database browsing techniques

We describe the implications of a study of database browsing behaviour for the development of a system to support more effective browsing. In particular we consider the importance of collaborative working, both in learning browsing skills and in co‐operating on a shared information‐retrieval task. From our study, we believe that an interface to support collaboration should promote the awareness of the activities of others, better visualization of the information data structures being browsed, and effective communication of the browsing process

Gaucher Disease and Myelofibrosis: A Combined Disease or a Misdiagnosis?

Background: Gaucher disease (GD) and primary myelofibrosis (PMF) share similar clinical and laboratory features, such as cytopenia, hepatosplenomegaly, and marrow fibrosis, often resulting in a misdiagnosis. Case Report: We report here the case of a young woman with hepatosplenomegaly, leukopenia, and thrombocytopenia. Based on bone marrow (BM) findings and on liver biopsy showing extramedullary hematopoiesis, an initial diagnosis of PMF was formulated. The patient refused stem cell transplantation from an HLA-identical sibling. Low-dose melphalan was given, without any improvement. Two years later, a BM evaluation showed Gaucher cells. Low glucocerebrosidase and high chitotriosidase levels were indicative for GD. Molecular analysis revealed N370S/complex I mutations. Enzyme replacement therapy with imiglucerase was commenced, resulting in clinical and hematological improvements. Due to an unexpected and persistent organomegaly, PMF combined with GD were suspected. JAK2V617F, JAK2 exon 12, MPL, calreticulin, and exon 9 mutations were negative, and BM examination showed no marrow fibrosis. PMF was excluded. Twenty years after starting treatment, the peripheral cell count and liver size were normal, whereas splenomegaly persisted. Conclusion: In order to avoid a misdiagnosis, a diagnostic algorithm for patients with hepatosplenomegaly combined with cytopenia is suggested

AI in marketing, consumer research and psychology: A systematic literature review and research agenda

This study is the first to provide an integrated view on the body of knowledge of artificial intelligence (AI) published in the marketing, consumer research, and psychology literature. By leveraging a systematic literature review using a data-driven approach and quantitative methodology (including bibliographic coupling), this study provides an overview of the emerging intellectual structure of AI research in the three bodies of literature examined. We identified eight topical clusters: (1) memory and computational logic; (2) decision making and cognitive processes; (3) neural networks; (4) machine learning and linguistic analysis; (5) social media and text mining; (6) social media content analytics; (7) technology acceptance and adoption; and (8) big data and robots. Furthermore, we identified a total of 412 theoretical lenses used in these studies with the most frequently used being: (1) the unified theory of acceptance and use of technology; (2) game theory; (3) theory of mind; (4) theory of planned behavior; (5) computational theories; (6) behavioral reasoning theory; (7) decision theories; and (8) evolutionary theory. Finally, we propose a research agenda to advance the scholarly debate on AI in the three literatures studied with an emphasis on cross-fertilization of theories used across fields, and neglected research topics

New selection rules for resonant Raman scattering on quantum wires

The bosonisation technique is used to calculate the resonant Raman spectrum of a quantum wire with two electronic sub-bands occupied. Close to resonance, the cross section at frequencies in the region of the inter sub-band transitions shows distinct peaks in parallel polarisation of the incident and scattered light that are signature of collective higher order spin density excitations. This is in striking contrast to the conventional selection rule for non-resonant Raman scattering according to which spin modes can appear only in perpendicular polarisation. We predict a new selection rule for the excitations observed near resonance, namely that, apart from charge density excitations, only spin modes with positive group velocities can appear as peaks in the spectra in parallel configuration close to resonance. The results are consistent with all of the presently available experimental data.Comment: 7 pages, 2 figure

The Storm Doesn’t Touch me!—The Role of Perceived Employability of Students and Graduates in the Pandemic Era

Perceived Employability acquires growing relevance as a psychological protective resource now that new entrants in the labour market from higher education are experiencing a deterioration of their occupational prospects due to the COVID-19 pandemic, which brings worries and jeopardises psychological well-being. This study aims to extend research on perceived employability among Italian University students and graduates. Perceived employability is posited to predict flourishing directly and indirectly by reducing material, social, and health worries related to COVID-19. Moreover, this study contends that perceived employability buffers the positive impact of perceived adverse conditions of the labour market on worries, changing the effect on flourishing. In total, 471 university students and graduates completed an online survey. The analyses reveal that perceived employability positively influences flourishing directly and indirectly by reducing COVID-19-related worries. Nevertheless, the results do not support the moderating action of perceived employability. Despite some limitations (e.g., a cross-sectional design), this study significantly advances the exploration of perceived employability as a critical personal resource to deal with the transition to work under pandemic-related crises. This study draws on its results to advise higher education to increase perceived employability, such as through career guidance activities and work-based learning experiences