Incipient quantum melting of the one-dimensional Wigner lattice

A one--dimensional tight--binding model of electrons with long--range Coulomb interactions is studied in the limit where double site occupancy is forbidden and the Coulomb coupling strength $V$ is large with respect to the hopping amplitude $t$. The quantum problem of a kink--antikink pair generated in the Wigner lattice (the classical ground state for $t=0$) is solved for fillings $n=1/s$, where $s$ is an integer larger than 1. The pair energy becomes negative for a relatively high value of $V$, $V_c/t\approx s^3$. This signals the initial stage of the quantum melting of the Wigner lattice

Variational Wave Function for Generalized Wigner Lattices in One Dimension

We study a system of electrons on a one-dimensional lattice, interacting through the long range Coulomb forces, by means of a variational technique which is the strong coupling analog of the Gutzwiller approach. The problem is thus the quantum version of Hubbard's classical model of the generalized Wigner crystal [J. Hubbard, Phys. Rev. B 17, 494 (1978)]. The magnetic exchange energy arising from quantum fluctuations is calculated, and turns out to be smaller than the energy scale governing charge degrees of freedom. This approach could be relevant in insulating quasi-one-dimensional compounds where the long range Coulomb interactions are not screened. In these compounds charge order often appears at high temperatures and coexists with magnetic order at low temperatures.Comment: 4 pages, proceedings of ECRYS-200

Changes in Imja Tsho in the Mount Everest Region of Nepal

Imja Tsho, located in the Sagarmatha ( Everest) National Park of Nepal, is one of the most studied and rapidly growing lakes in the Himalayan range. Compared with previous studies, the results of our sonar bathymetric survey conducted in September of 2012 suggest that its maximum depth has increased from 90.5 to 116.3 +/- 5.2 m since 2002, and that its estimated volume has grown from 35.8 +/- 0.7 to 61.7 +/- 3.7 million m(3). Most of the expansion of the lake in recent years has taken place in the glacier terminus-lake interface on the eastern end of the lake, with the glacier receding at about 52 m yr(-1) and the lake expanding in area by 0.04 km(2) yr(-1). A ground penetrating radar survey of the Imja-Lhotse Shar glacier just behind the glacier terminus shows that the ice is over 200 m thick in the center of the glacier. The volume of water that could be released from the lake in the event of a breach in the damming moraine on the western end of the lake has increased to 34.1 +/- 1.08 million m(3) from the 21 million m(3) estimated in 2002.USAID Climate Change Resilient Development (CCRD) projectFulbright FoundationNational Geographic SocietyCenter for Research in Water Resource

Exponential torsion growth for random 3-manifolds

We show that a random 3-manifold with positive first Betti number admits a tower of cyclic covers with exponential torsion growth

Vínculos sociales y subsistencia en los «Templos de refugio» en Japón: Una exploración de las influencias en la situación de calle entre los jornaleros de los yoseba en Tokio

El trabajo por jornal se describe a menudo como no estructurado, lo que hace ambigua su capacidad de servir como trampa en la situación de calle o como paso hacia la economía formal. Exploramos esta cuestión describiendo los factores que influyen en la situación de calle entre los jornaleros. Analizamos datos de encuestas del mayor yoseba de Tokio, o enclave del trabajo por jornal, y hallamos que los jornaleros evitaron la situación de calle por más días trabajados, educación, permanencia en el cargo como jornalero, y conexiones interpersonales con los intermediarios. La atención a experiencias acumulativas y lazos sociales en los mercados de trabajo por jornal es crucial para entender su estructura, dinámica, funciones y efectos en las trayectorias a largo plazo de los trabajadores

Effect of Coulomb interactions on the optical properties of doped graphene

Recent optical conductivity experiments of doped graphene in the infrared regime reveal a strong background in the energy region between the intra and interband transitions difficult to explain within conventional pictures. We propose a phenomenological model taking into account the marginal Fermi liquid nature of the quasiparticles in graphene near the neutrality point that can explain qualitatively the observed features. We also study the electronic Raman signal and suggest that it will also be anomalous.Comment: 4 pages, 2 figure

Therapeutic possibilities of plasmonically heated gold nanoparticles

Nanoparticles of gold, which are in the size range 10-100 nm, undergo a plasmon resonance with light. This is a process whereby the electrons of the gold resonate in response to incoming radiation causing them to both absorb and scatter light. This effect can be harnessed to either destroy tissue by local heating or release payload molecules of therapeutic importance. Gold nanoparticles can also be conjugated to biologically active moieties, providing possibilities for targeting to particular tissues. Here, we review the progress made in the exploitation of the plasmon resonance of gold nanoparticles in photo-thermal therapeutic medicine. © 2005 Elsevier Ltd. All rights reserved

An Anti-C1s Monoclonal, TNT003, Inhibits Complement Activation Induced by Antibodies Against HLA.

Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro