Curvature-induced spin-orbit coupling and spin relaxation in a chemically clean single-layer graphene

The study of spin-related phenomena in materials requires knowledge on the precise form of effective spin-orbit coupling of conducting carriers in the solid-states systems. We demonstrate theoretically that curvature induced by corrugations or periodic ripples in single-layer graphenes generates two types of effective spin-orbit coupling. In addition to the spin-orbit coupling reported previously that couples with sublattice pseudospin and corresponds to the Rashba-type spin-orbit coupling in a corrugated single-layer graphene, there is an additional spin-orbit coupling that does not couple with the pseudospin, which can not be obtained from the extension of the curvature-induced spin-orbit coupling of carbon nanotubes. Via numerical calculation we show that both types of the curvature-induced spin-orbit coupling make the same order of contribution to spin relaxation in chemically clean single-layer graphene with nanoscale corrugation. The spin relaxation dependence on the corrugation roughness is also studied.Comment: 8 pages, 4 figure

Kaon semileptonic decay (K_{l3}) form factors from the instanton vacuum

We investigate the kaon semileptonic decay (K_{l3}) form factors within the framework of the nonlocal chiral quark model from the instanton vacuum, taking into account the effects of flavor SU(3) symmetry breaking. We also consider the problem of gauge invariance arising from the momentum-dependent quark mass in the present work. All theoretical calculations are carried out without any adjustable parameter, the average instanton size (rho ~ 1/3 fm) and the inter-instanton distance (R ~ 1 fm) having been fixed. We also show that the present results satisfy the Callan-Treiman low-energy theorem as well as the Ademollo-Gatto theorem. Using the K_{l3} form factors, we evaluate relevant physical quantities. It turns out that the effects of flavor SU(3) symmetry breaking are essential in reproducing the kaon semileptonic form factors. The present results are in a good agreement with experiments, and are compatible with other model calculations.Comment: 12 pages, 3 figures, submitted to PR

Service to-go: The Customer Experience in the Street Food Sector through the Eyes of its Operators

Since the proclamation of the experience economy (Pine & Gilmore, 1998), companies have turned their focus from selling goods to selling experiences. The street food sector has been serving up experiences since the 1700s. Yet very little is actually known in regards to how these business entities deliver these experiences. The purpose of this study is to explore street food vendor operators’ perception of the factors that contribute to the customer experience in the street food sector. In doing so, this paper provides valuable information about demographics of street food operators and customers, what kinds of experiences they are opt to deliver, and the reasons why their customers eat street food

Geodesic Motions in 2+1 Dimensional Charged Black Holes

We study the geodesic motions of a test particle around 2+1 dimensional charged black holes. We obtain a class of exact geodesic motions for the massless test particle when the ratio of its energy and angular momentum is given by square root of cosmological constant. The other geodesic motions for both massless and massive test particles are analyzed by use of numerical method.Comment: 13page

Authenticity in Tourism in Small Island Destinations: the Residents’ Perspective

This study explored the meaning of authenticity in the context of a small island destination from the residents\u27 perspective, departing from the main stream literature which predominantly focuses on the demand side of the equation. Photo-elicitation was used to investigate the conception of authenticity. The finding from the focus group is that the notions of authenticity are unique, vast, and individualistic and that an encompassing definition of authenticity is difficult to concur. While the focus group provided clarity in terms of authenticity being embedded in the cultural lifestyle, an empirical study was conducted to further understand what cultural resources could be derived from the specific meaning of authenticity. Two themes emerged: (1) when residents interact with tourists, cultural attributes are more important than tradition; and (2) tourists are involved in creating an authentic process for residents. The younger generation appears to be frustrated with the impact of tourism on the cultural identity of the island. In conclusion, the concept and practice of authenticity are not static, but rather evolving practices that embrace new cultural forms. Cultural tourism could become a potent vehicle enhancing the quality of life of residents and the essence of the distinctiveness of Aruba contributing to a sense of place, pride, and culture

Autophagy in Adipocyte Browning: Emerging Drug Target for Intervention in Obesity

Autophagy, lipophagy, and mitophagy are considered to be the major recycling processes for protein aggregates, excess fat, and damaged mitochondria in adipose tissues in response to nutrient status-associated stress, oxidative stress, and genotoxic stress in the human body. Obesity with increased body weight is often associated with white adipose tissue (WAT) hypertrophy and hyperplasia and/or beige/brown adipose tissue atrophy and aplasia, which significantly contribute to the imbalance in lipid metabolism, adipocytokine secretion, free fatty acid release, and mitochondria function. In recent studies, hyperactive autophagy in WAT was observed in obese and diabetic patients, and inhibition of adipose autophagy through targeted deletion of autophagy genes in mice improved anti-obesity phenotypes. In addition, active mitochondria clearance through activation of autophagy was required for beige/brown fat whitening – that is, conversion to white fat. However, inhibition of autophagy seemed detrimental in hypermetabolic conditions such as hepatic steatosis, atherosclerosis, thermal injury, sepsis, and cachexia through an increase in free fatty acid and glycerol release from WAT. The emerging concept of white fat browning–conversion to beige/brown fat– has been controversial in its anti-obesity effect through facilitation of weight loss and improving metabolic health. Thus, proper regulation of autophagy activity fit to an individual metabolic profile is necessary to ensure balance in adipose tissue metabolism and function, and to further prevent metabolic disorders such as obesity and diabetes. In this review, we summarize the effect of autophagy in adipose tissue browning in the context of obesity prevention and its potential as a promising target for the development of anti-obesity drugs

Hydrated copper and gold monovalent cations: Ab initio study

To understand the hydration phenomena of noble transition metals, we investigated the structures, hydration energies, electronic properties, and spectra of the Cu+(H3O)(1-6) and Au+ (H2O)(1-6) clusters using ab initio calculations. The coordination numbers of these clusters are found to be only two, which is highly contrasted to those of Ag+ (H2O)(n) (which have the coordination numbers of 3-4) as well as the hydrated alkali metal ions (which have the coordination numbers of similar to6). For the possible identification of their interesting hydration structures, we predict their IR spectra for the OH stretch modes. (C) 2005 American Institute of Physics.open384

Imaging Mechanism of Piezoresponse Force Microscopy in Capacitor Structures

The image formation mechanism in Piezoresponse Force Microscopy (PFM) of capacitor structures is analyzed. We demonstrate that the spatial resolution is a bilinear function of film and top electrode thicknesses, and derive the corresponding analytical expressions. For many perovskites, the opposite contributions of d31 and d33 components can result in anomalous domain wall profiles. This analysis establishes the applicability limits of PFM for polarization dynamics studies in capacitors, and applies to other structural probes, including focused X-ray studies of capacitor structures.Comment: 20 pages, 3 figures, 2 tables, 1 Aappendix, to be submitted to Appl. Phys. Let

KMT-2016-BLG-1107: A New Hollywood-Planet Close/Wide Degeneracy

We show that microlensing event KMT-2016-BLG-1107 displays a new type of degeneracy between wide-binary and close-binary Hollywood events in which a giant-star source envelops the planetary caustic. The planetary anomaly takes the form of a smooth, two-day "bump" far out on the falling wing of the light curve, which can be interpreted either as the source completely enveloping a minor-image caustic due to a close companion with mass ratio $q=0.036$, or partially enveloping a major-image caustic due to a wide companion with $q=0.004$. The best estimates of the companion masses are both in the planetary regime ($3.3^{+3.5}_{-1.8}\,M_{\rm jup}$ and $0.090^{+0.096}_{-0.037}\,M_{\rm jup}$) but differ by an even larger factor than the mass ratios due to different inferred host masses. We show that the two solutions can be distinguished by high-resolution imaging at first light on next-generation ("30m") telescopes. We provide analytic guidance to understand the conditions under which this new type of degeneracy can appear.Comment: 23 pages, 7 figures, accepted for publication in A