Position-dependent mass models and their nonlinear characterization

We consider the specific models of Zhu-Kroemer and BenDaniel-Duke in a sech$^{2}$-mass background and point out interesting correspondences with the stationary 1-soliton and 2-soliton solutions of the KdV equation in a supersymmetric framework.Comment: 8 Pages, Latex version, Two new references are added, To appear in J.Phys.A (Fast Track Communication

Proposal to determine the Fermi-surface topology of a doped iron-based superconductor using bulk-sensitive Fourier-transform Compton scattering

We have carried out first-principles calculations of the Compton scattering spectra to demonstrate that the filling of the hole Fermi surface in LaO$_{1-x}$F$_{x}$FeAs produces a distinct signature in the Fourier transformed Compton spectrum when the momentum transfer vector lies along the [100] direction. We thus show how the critical concentration $x_c$, where hole Fermi surface pieces are filled up and the superconductivity mediated by antiferromagnetic spin fluctuations is expected to be suppressed, can be obtained in a bulk-sensitive manner.Comment: 4 pages, 6 figures, accepted in Physical Review

Projectile Δ\Delta Excitations in p(p,n)Nπp(p,n)N\pi Reactions

It has recently been proven from measurements of the spin-transfer coefficients $D_{xx}$ and $D_{zz}$ that there is a small but non-vanishing $\Delta S=0$ component $\sigma_{0}$, in the inclusive $p(p,n)N\pi\,$ reaction cross section $\sigma\,$. It is shown that the dominant part of the measured $\sigma_{0}$ can be explained in terms of the projectile $\Delta$ excitation mechanism. An estimate is further made of contributions to $\sigma_{0}$ from s-wave rescattering process. It is found that s-wave rescattering contribution is much smaller than the contribution coming from projectile $\Delta$ excitation mechanism. The addition of s-wave rescattering contribution to the dominant part, however, improves the fit to the data.Comment: 9 pages, Revtex, figures can be obtained upon reques

Exact solution and interfacial tension of the six-vertex model with anti-periodic boundary conditions

We consider the six-vertex model with anti-periodic boundary conditions across a finite strip. The row-to-row transfer matrix is diagonalised by the `commuting transfer matrices' method. {}From the exact solution we obtain an independent derivation of the interfacial tension of the six-vertex model in the anti-ferroelectric phase. The nature of the corresponding integrable boundary condition on the $XXZ$ spin chain is also discussed.Comment: 18 pages, LaTeX with 1 PostScript figur

Strings Inside Walls in N=1 Super Yang-Mills

We conjecture the existence of strings bounded inside walls in SU$(n)$ $\N=1$ Super Yang-Mills theory. These strings carry $\Z_{[k,n]}$ quantum number, where $[k,n]$ is the greatest common divisor between $k$, the charge of the wall, and $n$. We provide field-theoretical arguments and string-theoretical evidences, both from MQCD and from gauge-gravity correspondence. We interpret this result from the point of view of the low-energy effective action living on the $k$-wall.Comment: 25 pp. Major changes. In particular, following the recent work arXiv:0807.1908 we have been able to give a field theoretical proof of the statement. We have also corrected an important erroneous interpretation in the previous version regarding the 2+1 effective action; Typo

Seeps, springs and wetlands: San Juan Basin, Colorado. Social-ecological climate resilience project

Prepared for: North Centeral Climate Adaptation Science Center.Social-Ecological Climate Resilience Project, 2016.Includes bibliographical references

Social Ecological Climate Resilience Project - 2016

Prepared for: North Central Climate Science Center, Fort Collins, Colorado.February 2017.Includes bibliographical references.Climate change is already having impacts on nature, ecosystem services and people in southwestern Colorado and is likely to further alter our natural landscapes in the coming decades. Understanding the potential changes and developing adaptation strategies can help ensure that natural landscapes and human communities remain healthy in the face of a changing climate. An interdisciplinary team consisting of social, ecological and climate scientists developed an innovative climate planning framework and worked with the Social‐Ecological Climate Resilience Project (SECR) and other stakeholders in Colorado’s San Juan River watershed to develop adaptation strategies for two significant landscapes, pinyon juniper woodlands and seeps, springs, and wetland resources under three climate scenarios between 2035 and 2050. This report summarizes the planning framework and results for the pinyon‐juniper landscape (the seeps, springs and wetlands results will be provided separately). This framework can be utilized to develop strategies for other landscapes at local, state, and national scales. Diagrams, narrative scenarios, and maps that depict climate scenarios and the social‐ecological responses help us portray the climate impact in the face of an uncertain future. Interviews and focus group workshops with agency staff and stakeholders who are users of public lands identified several important opportunities to improve the adaptation planning process for developing strategies that meet both social and ecological needs. Planning techniques that include or directly relate to specific resources, such as water and forage, or to activities, such as recreation or grazing, provide avenues for engaging diverse stakeholders into the process. Utilizing the scenarios to understand the impacts to our social and ecological landscapes, three overarching landscape‐scale adaptation strategies were developed. Each of these strategies has a suite of potential actions required to reach a desired future condition. The three key strategies are: 1) identify and protect persistent ecosystems as refugia, 2) proactively manage for resilience, and 3) accept, assist, and allow for transformation in non‐climate refugia sites. If the framework and strategies from this project are adopted by the local community, including land managers, owners, and users, the climate change impacts can be reduced, allowing for a more sustainable human and natural landscape

Sagebrush landscape: Upper Gunnison River Basin, Colorado Social-Ecological Climate Resilience Project

Prepared with: The Gunnison Climate Working Group and Stakeholders in Gunnison, Colorado for: the North Central Climate Science Center, Ft. Collins, Colorado.April 30, 2017.Includes bibliographical references.Utilizing climate stories to understand the social and ecological impacts to the sagebrush landscape, the team worked with stakeholders to develop three overarching landscape‐scale adaptation strategies. Each of the strategies has a suite of potential actions required to reach a desired future condition. The three key strategies are: 1) identify and protect climate refugia sites (persistent areas), 2) maintain or enhance the resilience of the climate refugia sites, and 3) accept, assist and allow for transformation in non‐climate refugia sites. If adopted by the local community, including land managers and landowners, the framework and strategies resulting from this project can help to reduce the adverse impacts of climate change, allowing for a more sustainable human and natural landscape

T Cell Integrin Overexpression as a Model of Murine Autoimmunity

Integrin adhesion molecules have important adhesion and signaling functions. They also play a central role in the pathogenesis of many autoimmune diseases. Over the past few years we have described a T cell adoptive transfer model to investigate the role of T cell integrin adhesion molecules in the development of autoimmunity. This report summarizes the methods we used in establishing this murine model. By treating murine CD4+ T cells with DNA hypomethylating agents and by transfection we were able to test the in vitro effects of integrin overexpression on T cell autoreactive proliferation, cytotoxicity, adhesion and trafficking. Furthermore, we showed that the ability to induce in vivo autoimmunity may be unique to the integrin lymphocyte function associated antigen-1 (LFA-1)