DERIVING SPECIES-SPECIFIC BENEFITS MEASURES FOR EXPECTED CATCH IMPROVEMENTS IN A RANDOM UTILITY FRAMEWORK

A random utility model of site choice is applied to marine recreational fishing trips in North Carolina. Expectations of catch rates of different species groups are estimated using a Poisson specification. A likelihood ratio test is employed to separate the expected catch of red drum (Scianops ocellatus) from a larger species group. Per trip measures of compensating variation are measured for two alternative specifications of an improvement in red drum catch, and the catch of other species groups. Willingness-to-pay measures are reported by fishing mode according to target species. Anglers targeting a particular species have higher willingness-to-pay than anglers targeting a different species, and anglers with any target have higher willingness-to-pay than anglers with no target.Resource /Energy Economics and Policy,

THE VALUE OF INCREASING THE LENGTH OF DEER SEASON IN OHIO

Growing deer populations are controlled through changes in hunting regulations including changes in both hunter bag limits and season length. Such action results in direct benefits to hunters and indirect benefits to motorists and the agricultural sector as a lower deer population leads to fewer incidences of human-deer encounters. Traditional recreation demand models are often employed to examine the welfare implications of changes in daily hunting bag limits. Studies measuring the effects of changes in season length, however, are noticeably absent from the literature. This study uses a nested random utility model to examine hunter choice over site and season selection to derive the welfare implications of changes in season length.random utility models, recreation, Resource /Energy Economics and Policy,

A DYNAMIC EXERCISE IN REDUCING DEER-VEHICLE COLLISIONS: MANAGEMENT THROUGH VEHICLE MITIGATION TECHNIQUES AND HUNTING

The costs of deer-vehicle collisions (DVCs) nationwide are estimated to be in excess of $1 billion annually. In this study, factors contributing to the abundance of DVCs are identified and the potential effectiveness of various deer management strategies in reducing DVCs is investigated. The added benefits of such strategies are also evaluated in a bioeconomic context by comparing alternative outcomes achievable from implementing DVC mitigation techniques. Focusing on Ohio, results suggest potentially large economic gains exist from reducing DVCs, especially with strategies that combine both deer management schemes and DVC mitigation techniques.Resource /Energy Economics and Policy,

Thin-disk laser pump schemes for large number of passes and moderate pump source quality

Novel thin-disk laser pump layouts are proposed yielding an increased number of passes for a given pump module size and pump source quality. These novel layouts result from a general scheme which bases on merging two simpler pump optics arrangements. Some peculiar examples can be realized by adapting standard commercially available pump optics simply by intro ducing an additional mirror-pair. More pump passes yield better efficiency, opening the way for usage of active materials with low absorption. In a standard multi-pass pump design, scaling of the number of beam passes brings ab out an increase of the overall size of the optical arrangement or an increase of the pump source quality requirements. Such increases are minimized in our scheme, making them eligible for industrial applicationsComment: 16 pages, 9 figure

Electrocatalysis in confined space

The complex interplay of restricted mass transport leading to local accumulation or depletion of educts, intermediates, products, counterions and co-ions influences the reactions at the active sites of electrocatalysts when electrodes are rough, three-dimensionally mesoporous or nanoporous. This influence is important with regard to activity, and even more to selectivity, of electrocatalytic reactions. The underlying principles are discussed based on the growing awareness of these considerations over recent years

Great Sumatra Earthquake Registers on Electrostatic Sensor

Strong electrical signals that correspond to the Mw = 9.3 earthquake of 26 December 2004, which occurred at 0058:50.7 UTC off the west coast of northern Sumatra, Indonesia, were recorded by an electrostatic sensor (a device that detects short-term variations in Earth’s electrostatic fi eld) at a seismic station in Italy, which had been installed to study the infl uence of local earthquakes on a new landslide monitoring system. Electrical signals arrived at the station practically instantaneously and were detected up to several hours before the onset of the Sumatra earthquake (Figure 1) as well as before local quakes. The corresponding seismic signals (p-waves) arrived 740 seconds after the start of the earthquake. Because the electrical signals travel at the speed of light, electrical monitoring for the global detection of very strong earthquakes could be an important tool in signifi cantly increasing the hazard alert window

The Influence of Nanoconfinement on Electrocatalysis

The use of nanoparticles and nanostructured electrodes are abundant in electrocatalysis. These nanometric systems contain elements of nanoconfinement in different degrees, depending on the geometry, which can have a much greater effect on the activity and selectivity than often considered. In this Review, we firstly identify the systems containing different degrees of nanoconfinement and how they can affect the activity and selectivity of electrocatalytic reactions. Then we follow with a fundamental understanding of how electrochemistry and electrocatalysis are affected by nanoconfinement, which is beginning to be uncovered, thanks to the development of new, atomically precise manufacturing and fabrication techniques as well as advances in theoretical modeling. The aim of this Review is to help us look beyond using nanostructuring as just a way to increase surface area, but also as a way to break the scaling relations imposed on electrocatalysis by thermodynamics

Apollo 14: Some geochemical aspects

Chemical analyses were obtained for five samples of Apollo 14 regolith fines, three 14230 core samples, soil clod 14049, breccias 14305 and 14319, 14310 basalt, and some separated phases. The chemical uniformity of these Apollo 14 samples indicates thorough mixing and/or uniform source rocks. Basalt 14310 can be matched well in composition by a four to one mixture of soil and plagioclase. The Eu(2+)/Eu(3+) ratios calculated for 14310 pigeonite and plagioclase are similar to those for Apollo 12 and 15 mare-type basalt phases; this indicates similar redox conditions. Apollo 14 samples are chemically similar to Apollo 12 and 15 KREEP as distinct from Apollo 11, 12, and 15 and Luna 16 mare-type basalts

The importance of nanoscale confinement to electrocatalytic performance

Electrocatalytic nanoparticles that mimic the three-dimensional geometric architecture of enzymes where the reaction occurs down a substrate channel isolated from bulk solution, referred to herein as nanozymes, were used to explore the impact of nano-confinement on electrocatalytic reactions. Surfactant covered Pt-Ni nanozyme nanoparticles, with Ni etched from the nanoparticles, possess a nanoscale channel in which the active sites for electrocatalysis of oxygen reduction are located. Different particle compositions and etching parameters allowed synthesis of nanoparticles with different average substrate channel diameters that have varying amounts of nano-confinement. The results showed that in the kinetically limited regime at low overpotentials, the smaller the substrate channels the higher the specific activity of the electrocatalyst. This is attributed to higher concentrations of protons, relative to bulk solution, required to balance the potential inside the nano-confined channel. However, at higher overpotentials where limitation by mass transport of oxygen becomes important, the nanozymes with larger substrate channels showed higher electrocatalytic activity. A reaction-diffusion model revealed that the higher electrocatalytic activity at low overpotentials with smaller substrate channels can be explained by the higher concentration of protons. The model suggests that the dominant mode of mass transport to achieve these high concentrations is by migration, exemplifying how nano-confinement can be used to enhance reaction rates. Experimental and theoretical data show that under mass transport limiting potentials, the nano-confinement has no effect and the reaction only occurs at the entrance of the substrate channel at the nanoparticle surface

An Artificial Enzyme: How Nanoconfinement Allows the Selective Electrochemical Detection of Glucose Directly in Whole Blood

Nanoparticles that catalyze biochemically relevant reactions are promoted as alternative enzymes. The application of such artificial enzymes is severely restricted by poor selectivity in biological fluids; mainly because the reactions occur at active sites on the exterior surface of the nanoparticle. Enzymes in contrast typically have their active sites down a nanoconfined substrate channel where the reaction occurs in different solution conditions to bulk solution which aids in achieving selectivity for the substrate. Herein the same 3D structure of enzymes is mimicked in nanoparticles to allow selective reactions in biological fluids. This is achieved using a gold nanoparticle coated in a conducting mesoporous carbon shell where isolated nanochannels lead to the gold surface. It can detect glucose in whole blood with no interference from other species. This is achieved by electrochemically pulsing the artificial enzymes to generate the locally required alkalinity for an effective electrocatalytic reaction in the nanochannels, as well as expelling fouling agents that will otherwise passivate the electrocatalytic reaction. The artificial enzymes are shown to be capable of detecting glucose in biological fluids, without loss of signal, for several months. This study shows how nanoconfinement in nanoparticles can be exploited to potentially allow a broad range of species to be selectively detected in biological fluids with stability that can exceed that of enzymes