Introduction: Reflections on nancy abelmann's legacy

Nancy Abelmann passed away on January 6, 2016, at the age of fifty-six. She received her PhD from the University of California, Berkeley in 1990, after completing her dissertation under Nelson Graburn. That same year, she was hired by the University of Illinois, Urbana-Champaign, where she worked for two and a half decades. She was a beloved teacher, mentor, and colleague to many, and she was a key figure in multiple departments and centers. At the time of her death, she held the Harold E. Preble Professorship in Anthropology, Asian American Studies, East Asian Languages and Cultures, and Women and Gender Studies and was also Associate Vice Chancellor for Research

Nearly Scale-Invariant Spectrum of Adiabatic Fluctuations May be from a Very Slowly Expanding Phase of the Universe

In this paper we construct an expanding phase with phantom matter, in which the scale factor expands very slowly but the Hubble parameter increases gradually, and assume that this expanding phase could be matched to our late observational cosmology by the proper mechanism. We obtain the nearly scale-invariant spectrum of adiabatic fluctuations in this scenario, different from the simplest inflation and usual ekpyrotic/cyclic scenario, the tilt of nearly scale-invariant spectrum in this scenario is blue. Although there exists an uncertainty surrounding the way in which the perturbations propagate through the transition in our scenario, which is dependent on the detail of possible "bounce" physics, compared with inflation and ekpyrotic/cyclic scenario, our work may provide another feasible cosmological scenario generating the nearly scale-invariant perturbation spectrum.Comment: 4 pages, no figures, to appear in Phys. Rev. D. Many thanks for referee's kind comments and criticism

Temporary Protection and Technology Choice Under the Learning Curve

No abstract.

Real-time imaging of pulvinus bending in Mimosa pudica

Mimosa pudica is a plant that rapidly shrinks its body in response to external stimuli. M. pudica does not perform merely simple movements, but exhibits a variety of movements that quickly change depending on the type of stimuli. Previous studies have investigated the motile mechanism of the plants from a biochemical perspective. However, an interdisciplinary study on the structural characteristics of M. pudica should be accompanied by biophysical research to explain the principles underlying such movements. In this study, the structural characteristics and seismonastic reactions of M. pudica were experimentally investigated using advanced bio-imaging techniques. The results show that the key factors for the flexible movements by the pulvinus are the following: bendable xylem bundle, expandable/shrinkable epidermis, tiny wrinkles for surface modification, and a xylem vessel network for efficient water transport. This study provides new insight for better understanding the M. pudica motile mechanism through structural modification.open1111Nsciescopu

Quantum FFLO state in clean layered superconductors

We investigate the influence of Landau quantization on the superconducting instability for a pure layered superconductor in the magnetic field directed perpendicular to the layers. We demonstrate that the quantization corrections to the Cooper-pairing kernel with finite Zeeman spin splitting promote the formation of the nonuniform state in which the order parameter is periodically modulated along the magnetic field, i.e., between the layers (Fulde-Ferrell-Larkin-Ovchinnikov [FFLO] state). The conventional uniform state experiences such a quantization-induced FFLO instability at low temperatures even in a common case of predominantly orbital suppression of superconductivity when the Zeeman spin splitting is expected to have a relatively weak effect. The maximum relative FFLO temperature is given by the ratio of the superconducting transition temperature and the Fermi energy. This maximum is realized when the ratio of the spin-spitting energy and the Landau-level separation is half-integer. These results imply that the FFLO states may exist not only in the Pauli-limited superconductors but also in very clean materials with small Zeeman spin-splitting energy. We expect that the described quantization-promoted FFLO instability is a general phenomenon, which may be found in materials with different electronic spectra and order-parameter symmetries.Comment: 18 pages, 10 figures, minor correction

Interplay between orbital-quantization effects and the Fulde-Ferrell-Larkin-Ovchinnikov instability in multiple-band layered superconductors

We explore superconducting instability for a clean two-band layered superconductor with deep and shallow bands in the magnetic field applied perpendicular to the layers. In the shallow band, the quasiclassical approximation is not applicable, and Landau quantization has to be accounted for exactly. The electronic spectrum of this band in the magnetic field is composed of the one-dimensional Landau-level minibands. With increasing magnetic field the system experiences series of Lifshitz transitions when the chemical potential enters and exits the minibands. These transitions profoundly influence the shape of the upper critical field at low temperatures. In addition, the Zeeman spin splitting may cause the nonuniform state with interlayer modulation of the superconducting order parameter (Fulde-Ferrell-Larkin-Ovchinnikov state). Typically, the quantization effects in the shallow band strongly promote the formation of this state. The uniform state remains favorable only in the exceptional resonance cases when the spin-splitting energy exactly matches the Landau-level spacing. Furthermore, for specific relations between electronic spectrum parameters, the alternating FFLO state may realize, in which the order parameter changes sign between the neighboring layers. For all above cases, the reentrant high-field superconducting states may emerge at low temperatures if the shallow band has significant contribution to the Cooper pairing.Comment: 25 pages, 14 figures, minor revisions and more references adde

Strong Landau-quantization effects in high-magnetic-field superconductivity of a two-dimensional multiple-band metal near the Lifshitz transition

We investigate the onset of superconductivity in magnetic field for a clean two-dimensional multiple-band superconductor in the vicinity of the Lifshitz transition when one of the bands is very shallow. Due to small number of carriers in this band, the quasiclassical Werthamer-Helfand approximation breaks down and Landau quantization has to be taken into account. We found that the transition temperature TC2(H) has giant oscillations and is resonantly enhanced at the magnetic fields corresponding to full occupancy of the Landau levels in the shallow band. This enhancement is especially pronounced for the lowest Landau level. As a consequence, the reentrant superconducting regions in the temperature-field phase diagram emerge at low temperatures near the magnetic fields at which the chemical potential matches the Landau levels. The specific behavior depends on the relative strength of the intraband and interband pairing interactions and the reentrance is most pronounced in the purely interband coupling scenario. The reentrant behavior is suppressed by the Zeeman spin splitting in the shallow band, the separated regions disappear already for very small spin-splitting factors. On the other hand, the reentrance is restored in the resonance cases when the spin-splitting energy exactly matches the separation between the Landau levels. The predicted behavior may realize in the gate-tuned FeSe monolayer.Comment: 23 pages, 9 figures, more references added and one figure adde