COMMUNITY CHOICES AND HOUSING DECISIONS: A SPATIAL ANALYSIS OF THE SOUTHERN APPALACHIAN HIGHLANDS

This paper examines land development using an integrated approach that combines residential decisions about choices of community in the Southern Appalachian region with the application of the GIS (Geographical Information System). The empirical model infers a distinctive heterogeneity in the characteristics of community choices. The results also indicate that socioeconomic motives strongly affect urban housing decisions while environmental amenities affect those of rural housing.Public Economics,

Skyrmion Generation by Current

Skyrmions, once a hypothesized field-theoretical object believed to describe the nature of elementary particles, became common sightings in recent years among several non-centrosymmetric metallic ferromagnets. For more practical applications of Skyrmionic matter as carriers of information, thus realizing the prospect of "Skyrmionics", it is necessary to have the means to create and manipulate Skyrmions individually. We show through extensive simulation of the Landau-Lifshitz-Gilbert equation that a circulating current imparted to the metallic chiral ferromagnetic system can create isolated Skyrmionic spin texture without the aid of external magnetic field.Comment: 8 pages, 5 figures, submitted to PR

Isospin particle on S2S^{2} with arbitrary number of supersymmetries

We study the supersymmetric quantum mechanics of an isospin particle in the background of spherically symmetric Yang-Mills gauge field. We show that on $S^{2}$ the number of supersymmetries can be made arbitrarily large for a specific choice of the spherically symmetric SU(2) gauge field. However, the symmetry algebra containing the supercharges becomes nonlinear if the number of fermions is greater than two. We present the exact energy spectra and eigenfunctions, which can be written as the product of monopole harmonics and a certain isospin state. We also find that the supersymmetry is spontaneously broken if the number of supersymmetries is even.Comment: 6 page

Interplay between Fermi surface topology and ordering in URu2_{2}Si2_2 revealed through abrupt Hall coefficient changes in strong magnetic fields

Temperature- and field-dependent measurements of the Hall effect of pure and 4 % Rh-doped URu$_{2}$Si$_{2}$ reveal low density (0.03 hole/U) high mobility carriers to be unique to the `hidden order' phase and consistent with an itinerant density-wave order parameter. The Fermi surface undergoes a series of abrupt changes as the magnetic field is increased. When combined with existing de Haas-van Alphen data, the Hall data expose a strong interplay between the stability of the `hidden order,' the degree of polarization of the Fermi liquid and the Fermi surface topology.Comment: 4 pages, 4 figures, Accepted to Phys. Rev. Let

Staggered Currents in the Vortex Core

We study the electronic structure of the vortex core in the cuprates using the U(1) slave-boson mean-field wavefunctions and their Gutzwiller projection. We conclude that there exists local orbital antiferromagnetic order in the core near optimal doping. We compare the results with that of BCS theory and analyze the spatial dependence of the local tunneling density of states.Comment: 4 pages, 3 figure

Skyrmion Lattice in Two-Dimensional Chiral Magnet

We develop a theory of the magnetic field-induced formation of Skyrmion crystal state in chiral magnets in two spatial dimensions, motivated by the recent discovery of the Skyrmionic phase of magnetization in thin film of Fe$_{0.5}$Co$_{0.5}$Si and in the A-phase of MnSi. Ginzburg-Landau functional of the chiral magnet re-written in the CP$^1$ representation is shown to be a convenient framework for the analysis of the Skyrmion states. Phase diagram of the model at zero temperature gives a sequence of ground states, helical spin $\rightarrow$ Skyrme crystal $\rightarrow$ ferromagnet, as the external field $B$ increases, in good accord with the thin-film experiment. In close analogy with Abrikosov's derivation of the vortex lattice solution in type-II superconductor, the CP$^1$ mean-field equation is solved and shown to reproduce the Skyrmion crystal state.Comment: 10 pages, 7 figure

Leader Readiness in a Volatile, Uncertain, Complex, and Ambiguous Business Environment

Organizational leaders in the 21st century face relentless changes in the business environments in which they operate. The diversity, intensity, and rapidity of these changes create volatility, uncertainty, complexity, and ambiguity (VUCA), which challenge leaders on ways to lead effectively as existing methods prove inadequate. The problem in this study was that of inadequate leader preparedness to lead and win in VUCA environments. The purpose of this hermeneutic phenomenological study was to explore the lived experiences of 15 Nigerian corporate executives about their VUCA business environment and the strategies they employed for VUCA-readiness and success using open-ended interview questions. The conceptual framework guiding this study was a combination of chaos theory and complexity leadership theory. Through Ricoeur’s theory of interpretation, member checking, and contextual triangulation, 11 key themes emerged to highlight key coping and readiness strategies for leaders operating in turbulent environments. The key recommendations for practice are to inculcate VUCA-readiness and organizational resilience principles in line with this study’s findings. The study findings may contribute to positive social change in providing strategies for organizational sustainability, firm success, business readiness, responsive leadership, and enhanced employee well-being

Endothelial function in migraine: a cross-sectional study

ABSTRACT: BACKGROUND: Migraine has been associated with cardiovascular disorders. Endothelial dysfunction may be a mechanism underlying this association. The present study tested the hypothesis that endothelium-dependent vasodilation, basal endothelial nitric oxide release and endothelial fibrinolytic capacity are impaired in migraine patients. METHODS: Graded doses of sodium nitroprusside (SNP, 0.2 to 0.8 microg.min 1.dL-1 forearm), substance P (0.2 to 0.8 pmol.min-1.dL-1 forearm) and NG monomethyl-L-arginine (L-NMMA, 0.1 to 0.4 micromol.min-1.dL-1 forearm) were infused into the brachial artery of 16 migraine patients with or without aura during a headache-free interval and 16 age- and sex-matched subjects without a history of migraine. Forearm blood flow (FBF) was measured by strain-gauge venous occlusion plethysmography. Local forearm release of tissue plasminogen activator (t-PA) in response to substance P infusion was assessed using the arteriovenous plasma concentration gradient. Responses to infused drugs were compared between patients and matched controls by analysis of variance. RESULTS: In both migraine patients and control subjects, SNP and substance P caused a dose-dependent increase, and L NMMA a dose-dependent decrease in FBF (P < 0.001 for all responses). In both groups, substance P caused an increase in t-PA release (P < 0.001). FBF responses and t-PA release were comparable between migraine patients and control subjects. CONCLUSIONS: The absence of differences in endothelium-dependent vasodilation, basal endothelial nitric oxide production and stimulated t-PA release between migraine patients and healthy control subjects argues against the presence of endothelial dysfunction in forearm resistance vessels of migraine patients.status: publishe