Comparing Ecosystem Service preferences between urban and rural dwellers

Urbanization can profoundly alter socioecological relationships, but its influence on how people perceive and value ecosystem services (ES) is poorly understood. We reviewed an emerging literature in which sociocultural valuation of ES is compared among urban and rural dwellers. This research suggests that, although regulating and cultural ES were highly valued by both rural and urban dwellers, urban dwellers tended to value provisioning ES less than rural dwellers did. Differences in ES valuation could result from different experiences, uses, and needs for ES of urban and rural dwellers. We also identified two key gaps in the literature that relate to understanding how diverse ES contribute differently to the well-being of rural and urban populations (and the relevance of these differences for environmental education and policy) and the changing roles of ES in developing countries and vulnerable ecosystems, such as small islands, that face pressing environmental, social, and economic challenges

Flame propagation across an obstacle: OH-PLIF and 2-D simulations with detailed chemistry

Flame propagation across a single obstacle inside a closed square channel is studied experimentally and numerically using a stoichiometric H_2/O_2 mixture at initial conditions 15 kPa and 300 K. The 50% blockage obstacle consists of a pair of fence-type obstacles mounted on the top and bottom walls of the channel. Direct optical visualization was performed using single-image measurement of the planar laser-induced fluorescence of the OH radical (OH-PLIF) and simultaneous high-speed schlieren video to study the flame topology and the flame tip velocity along the channel streamwise axis, respectively. The OH-PLIF images provide a novel level of detail and permit a thorough evaluation of the simulation accuracy. The flame tip accelerates to a peak velocity of 590 m/s just downstream of the obstacle followed by a deceleration and subsequent re-acceleration. The unburnt gas flow ahead of the flame is subsonic at all times. The flame does not show any signs of diffusive-thermal instability. Vortex–flame interactions in the recirculation zones downstream of the obstacle wrinkle the flame. The numerical simulations, based on solving the 2-D compressible reactive Navier–Stokes equations with detailed chemistry, predict the flame tip velocity accurately. However, differences in flame topology are observed, specifically, wrinkling is over-estimated. The over-prediction of flame wrinkling suggests a lower dissipation rate in the numerical simulations than in reality, which could be a consequence of neglecting the third channel dimension. Conditional means of the fuel consumption rate are similar to the consumption rates of 1-D unstretched laminar flames at all times. The increase in pressure during flame propagation causes an increase in fuel consumption rate which needs to be accounted for in simplified modeling approaches

Coulomb and Spin blockade of two few-electrons quantum dots in series in the co-tunneling regime

We present Coulomb Blockade measurements of two few-electron quantum dots in series which are configured such that the electrochemical potential of one of the two dots is aligned with spin-selective leads. The charge transfer through the system requires co-tunneling through the second dot which is $not$ in resonance with the leads. The observed amplitude modulation of the resulting current is found to reflect spin blockade events occurring through either of the two dots. We also confirm that charge redistribution events occurring in the off-resonance dot are detected indirectly via changes in the electrochemical potential of the aligned dot.Comment: 6 pages, 5 figures, submitted to Phys. Rev.

Charge Sensing of an Artificial H2+ Molecule

We report charge detection studies of a lateral double quantum dot with controllable charge states and tunable tunnel coupling. Using an integrated electrometer, we characterize the equilibrium state of a single electron trapped in the doubled-dot (artificial H2+ molecule) by measuring the average occupation of one dot. We present a model where the electrostatic coupling between the molecule and the sensor is taken into account explicitly. From the measurements, we extract the temperature of the isolated electron and the tunnel coupling energy. It is found that this coupling can be tuned between 0 and 60 micro electron-volt in our device.Comment: 5 pages, 4 figures. Revised version with added material. To be published in Physical Review

Common Algebraic Structure for the Calogero-Sutherland Models

We investigate common algebraic structure for the rational and trigonometric Calogero-Sutherland models by using the exchange-operator formalism. We show that the set of the Jack polynomials whose arguments are Dunkl-type operators provides an orthogonal basis for the rational case.Comment: 7 pages, LaTeX, no figures, some text and references added, minor misprints correcte

Rodrigues Formula for the Nonsymmetric Multivariable Hermite Polynomial

Applying a method developed by Takamura and Takano for the nonsymmetric Jack polynomial, we present the Rodrigues formula for the nonsymmetric multivariable Hermite polynomial.Comment: 5 pages, LaTe

Rodrigues Formula for the Nonsymmetric Multivariable Laguerre Polynomial

Extending a method developed by Takamura and Takano, we present the Rodrigues formula for the nonsymmetric multivariable Laguerre polynomials which form the orthogonal basis for the $B_{N}$-type Calogero model with distinguishable particles. Our construction makes it possible for the first time to algebraically generate all the nonsymmetric multivariable Laguerre polynomials with different parities for each variable.Comment: 6 pages, LaTe

Theory of electronic transport through a triple quantum dot in the presence of magnetic field

Theory of electronic transport through a triangular triple quantum dot subject to a perpendicular magnetic field is developed using a tight binding model. We show that magnetic field allows to engineer degeneracies in the triple quantum dot energy spectrum. The degeneracies lead to zero electronic transmission and sharp dips in the current whenever a pair of degenerate states lies between the chemical potential of the two leads. These dips can occur with a periodicity of one flux quantum if only two levels contribute to the current or with half flux quantum if the three levels of the triple dot contribute. The effect of strong bias voltage and different lead-to-dot connections on Aharonov-Bohm oscillations in the conductance is also discussed