Janus configurations with SL(2,Z)-duality twists, Strings on Mapping Tori, and a Tridiagonal Determinant Formula

We develop an equivalence between two Hilbert spaces: (i) the space of states of $U(1)^n$ Chern-Simons theory with a certain class of tridiagonal matrices of coupling constants (with corners) on $T^2$; and (ii) the space of ground states of strings on an associated mapping torus with $T^2$ fiber. The equivalence is deduced by studying the space of ground states of $SL(2,Z)$-twisted circle compactifications of $U(1)$ gauge theory, connected with a Janus configuration, and further compactified on $T^2$. The equality of dimensions of the two Hilbert spaces (i) and (ii) is equivalent to a known identity on determinants of tridiagonal matrices with corners. The equivalence of operator algebras acting on the two Hilbert spaces follows from a relation between the Smith normal form of the Chern-Simons coupling constant matrix and the isometry group of the mapping torus, as well as the torsion part of its first homology group.Comment: 21 pages, typos correcte

Extension Education Drives Economic Stimulus Through Trade Adjustment Assistance for Farmers

Trade Adjustment Assistance for Farmers (TAAF) is a national multifaceted USDA program that provided technical and financial assistance to farmers and fishermen adversely affected by import competition. This article describes how Extension was successfully mobilized to deliver the TAAF program to 10,983 producers across the nation using innovative education technologies to achieve program objectives and improve the economic well-being of participating farmers and fisherman. The innovative technologies included online curricula and business planning, the use of personal business planning consultants, and linking Extension education outcomes to financial assistance payments that producers used primarily to invest in their business

Development of a Leadership Mindset Scale

The purpose of the study was to construct a Leadership Mindset Scale (LMS) and to assess its reliability and construct validity. Participants were 100 employees in a variety of leadership and non-leadership positions at various organizations in three states. An item and factor analysis on the 13 LMS items led to a scale with 11 items (Cronbach α = .80). A Principal Axis Factor analysis with Promax rotation suggested three factors: Leadership Mindset Teachability (LMS-T), a belief in leadership teachability; Leadership Mindset Improvability (LMS-I), a belief in leadership improvability over time; and Leadership Mindset Predictability (LMS-P), a belief that leadership cannot be predicted at an early age. Convergent validity of LMS-Total and Teachability was evidenced by significant correlations with the implicit theories of intelligence and anxiety scales, and developmental leadership and transactional leadership scales. Divergent validity was evidenced by a non-significant correlation with social desirability. The results suggest that the LMS measures a construct different from those of other leadership scales used in the study. The LMS can be helpful in leadership training programs to promote a growth mindset about the trainability of leadership skills

Pathogenic alpha-synuclein aggregates preferentially bind to mitochondria and affect cellular respiration

Abstract Misfolded alpha-synuclein (αSyn) is a major constituent of Lewy bodies and Lewy neurites, which are pathological hallmarks of Parkinson’s disease (PD). The contribution of αSyn to PD is well established, but the detailed mechanism remains obscure. Using a model in which αSyn aggregation in primary neurons was seeded by exogenously added, preformed αSyn amyloid fibrils (PFF), we found that a majority of pathogenic αSyn (indicated by serine 129 phosphorylated αSyn, ps-αSyn) was membrane-bound and associated with mitochondria. In contrast, only a minuscule amount of physiological αSyn was mitochondrial bound. In vitro, αSyn PFF displayed a stronger binding to purified mitochondria than did αSyn monomer, revealing a preferential mitochondria binding by aggregated αSyn. This selective mitochondrial ps-αSyn accumulation was confirmed in other neuronal and animal αSyn aggregation models that do not require exogenously added PFF and, more importantly, in postmortem brain tissues of patients suffering from PD and other neurodegenerative diseases with αSyn aggregation (α-synucleinopathies). We also showed that the mitochondrial ps-αSyn accumulation was accompanied by defects in cellular respiration in primary neurons, suggesting a link to mitochondrial dysfunction. Together, our results show that, contrary to physiological αSyn, pathogenic αSyn aggregates preferentially bind to mitochondria, indicating mitochondrial dysfunction as the common downstream mechanism for α-synucleinopathies. Our findings suggest a plausible model explaining the formation and the peculiar morphology of Lewy body and reveal that disrupting the interaction between ps-αSyn and the mitochondria is a therapeutic target for α-synucleinopathies.https://deepblue.lib.umich.edu/bitstream/2027.42/148288/1/40478_2019_Article_696.pd

Branes, Rings and Matrix Models in Minimal (Super)string Theory

We study both bosonic and supersymmetric (p,q) minimal models coupled to Liouville theory using the ground ring and the various branes of the theory. From the FZZT brane partition function, there emerges a unified, geometric description of all these theories in terms of an auxiliary Riemann surface M_{p,q} and the corresponding matrix model. In terms of this geometric description, both the FZZT and ZZ branes correspond to line integrals of a certain one-form on M_{p,q}. Moreover, we argue that there are a finite number of distinct (m,n) ZZ branes, and we show that these ZZ branes are located at the singularities of M_{p,q}. Finally, we discuss the possibility that the bosonic and supersymmetric theories with (p,q) odd and relatively prime are identical, as is suggested by the unified treatment of these models.Comment: 72 pages, 3 figures, improved treatment of FZZT and ZZ branes, minor change

Connecting Teachers, Students and Pre-Service Teachers to Improve STEM Pathways in Schools

This paper presents an example of collaboration between teacher educators, pre-service teachers, current teachers and school students that had a primary aim to increase student interest in STEM activities through a MakerSpace STEM club, while improving pre-service teachers’ confidence in delivering the Australian Curriculum: Technologies. The benefit of close relationships between universities and schools provides the framework for collaborative learning opportunities for pre-service teachers and school students. University academics were facilitators in the process, managing the external grant application and wider community workshops as well as embedding the activities in the university curricula. The school teachers managed the internal delivery of the MakerSpace club and promotion of STEM activities in their schools. All worked collaboratively to provide two professional development workshops, supported by a grant from the Google CS4HS program. Outcomes of this research demonstrate a student-centred approach to digital technology education. This model of collaboration between teacher educators and schools is replicable and has a positive impact on preparing pre-service teachers to be classroom ready

Q-balls of Quasi-particles in a (2,0)-theory model of the Fractional Quantum Hall Effect

A toy model of the fractional quantum Hall effect appears as part of the low-energy description of the Coulomb branch of the $A_1$ (2,0)-theory formulated on $(S^1\times R^2)/Z_k$, where the generator of $Z_k$ acts as a combination of translation on $S^1$ and rotation by $2\pi/k$ on $R^2$. At low energy the configuration is described in terms of a 4+1D Super-Yang-Mills theory on a cone ($R^2/Z_k$) with additional 2+1D degrees of freedom at the tip of the cone that include fractionally charged particles. These fractionally charged quasi-particles are BPS strings of the (2,0)-theory wrapped on short cycles. We analyze the large $k$ limit, where a smooth cigar-geometry provides an alternative description. In this framework a W-boson can be modeled as a bound state of $k$ quasi-particles. The W-boson becomes a Q-ball, and it can be described as a soliton solution of Bogomolnyi monopole equations on a certain auxiliary curved space. We show that axisymmetric solutions of these equations correspond to singular maps from $AdS_3$ to $AdS_2$, and we present some numerical results and an asymptotic expansion.Comment: 44 pages, 4 figures, new version includes corrections to typos and corrections to section