The Demand for Eastern Oysters, Crassostrea virginica, from the Gulf of Mexico in the Presence of Vibrio vulnificus

California, in response to health concerns, initiated a program on 1 March 1991 which required anyone selling eastern oysters, Crassostrea virginica, from the Gulf of Mexico area to notify potential consumers that there was a risk in consuming them raw. This mandatory warning, followed shortly thereafter by a similar warning in other states, including Louisiana and Florida, received extensive press cover-age throughout the country and particularly in the Gulf area. This paper examines the extent to which the demand for Gulf-area oysters has been reduced as a result of mandatory warning labels and negative publicity. In general, the results suggest that since 1991 the “summer” dockside price has been reduced by about 50% as a result of warning labels and associated negative publicity, while the “winter” dockside price has been reduced by about 30%

Effect of a Flared Renal Stent on the Performance of Fenestrated Stent-Grafts at Rest and Exercise Conditions

Purpose: To quantify the hemodynamic impact of a flared renal stent on the performance of fenestrated stent-grafts (FSGs) by analyzing flow patterns and wall shear stress–derived parameters in flared and nonflared FSGs in different physiologic scenarios. Methods: Hypothetical models of FSGs were created with and without flaring of the proximal portion of the renal stent. Flared FSGs with different dilation angles and protrusion lengths were examined, as well as a nonplanar flared FSG to account for lumbar curvature. Laminar and pulsatile blood flow was simulated by numerically solving Navier-Stokes equations. A physiologically realistic flow rate waveform was prescribed at the inlet, while downstream vasculature was modeled using a lumped parameter 3-element windkessel model. No slip boundary conditions were imposed at the FSG walls, which were assumed to be rigid. While resting simulations were performed on all the FSGs, exercise simulations were also performed on a flared FSG to quantify the effect of flaring in different physiologic scenarios. Results: For cycle-averaged inflow of 2.94 L/min (rest) and 4.63 L/min (exercise), 27% of blood flow was channeled into each renal branch at rest and 21% under exercise for all the flared FSGs examined. Although the renal flow waveform was not affected by flaring, flow within the flared FSGs was disturbed. This flow disturbance led to high endothelial cell activation potential (ECAP) values at the renal ostia for all the flared geometries. Reducing the dilation angle or protrusion length and exercise lowered the ECAP values for flared FSGs. Conclusion: Flaring of renal stents has a negligible effect on the time dependence of renal flow rate waveforms and can maintain sufficient renal perfusion at rest and exercise. Local flow patterns are, however, strongly dependent on renal flaring, which creates a local flow disturbance and may increase the thrombogenicity at the renal ostia. Smaller dilation angles, shorter protrusion lengths, and moderate lower limb exercise are likely to reduce the risk of thrombosis in flared geometries

Simulation study of a new InGaN p-layer free Schottky based solar cell

On the road towards next generation high efficiency solar cells, the ternary Indium Gallium Nitride (InGaN) alloy is a good passenger since it allows to cover the whole solar spectrum through the change in its Indium composition. The choice of the main structure of the InGaN solar cell is however crucial. Obtaining a high efficiency requires to improve the light absorption and the photogenerated carriers collection that depend on the layers parameters, including the Indium composition, p-and n-doping, device geometry.. . Unfortunately, one of the main drawbacks of InGaN is linked to its p-type doping, which is very difficult to realize since it involves complex technological processes that are difficult to master and that highly impact the layer quality. In this paper, the InGaN p-n junction (PN) and p-in junction (PIN) based solar cells are numerically studied using the most realistic models, and optimized through mathematically rigorous multivariate optimization approaches. This analysis evidences optimal efficiencies of 17.8% and 19.0% for the PN and PIN structures. It also leads to propose, analyze and optimize player free InGaN Schottky-Based Solar Cells (SBSC): the Schottky structure and a new MIN structure for which the optimal efficiencies are shown to be a little higher than for the conventional structures: respectively 18.2% and 19.8%. The tolerance that is allowed on each parameter for each of the proposed cells has been studied. The new MIN structure is shown to exhibit the widest tolerances on the layers thicknesses and dopings. In addition to its being player free, this is another advantage of the MIN structure since it implies its better reliability. Therefore, these new InGaN SBSC are shown to be alternatives to the conventional structures that allow removing the p-type doping of InGaN while giving photovoltaic (PV) performances at least comparable to the standard multilayers PN or PIN structures.Comment: Superlattices and Microstructures, Elsevier, 201

IMPACT OF INCREASING IMPORTS ON THE UNITED STATES SOUTHEASTERN REGION SHRIMP PROCESSING INDUSTRY 1973-1996

This study analyzes the effects of increased shrimp imports on the price-cost margins in three sectors of the U.S. shrimp industry. Results indicates decreasing price-cost margins for peeled shrimp, breaded shrimp, and headless-shell-on shrimp. The increase in shrimp imports reduces domestic processor prices for shrimp products, therefore decreasing processor margins.Demand and Price Analysis, International Relations/Trade,

The Gulf of Mexico Grouper Fisheries: Heterogeneous Fleet and Expectations in Fishermen's Decision

This study focuses on Gulf of Mexico Fishermen's expectations about their revenues and risks when participating in the grouper fishery using handlines or longlines. Results indicated that expected revenues follow a seasonnal and a spatial pattern. Fishermen using longline are risk averse while handliners are risk takers.Resource /Energy Economics and Policy,

TECHNOLOGY AND MANAGEMENT IN MAURITANIAN CEPHALOPOD FISHERIES

If the technology in a multi-species fishery is such that there is jointness in inputs and non-separability between inputs and outputs, then management on a species-by-species basis may lead to unintended outcomes, including over-exploitation of the resource. This study investigates the nature of the technical and economic relationships underlying the 1989-1990 Mauritanian cephalopod fishery by estimating a system of dual output supply functions derived from a generalized Leontief revenue function. Model results indicate the existence of jointness in inputs and non-separability between inputs and outputs in the fishery. Cross-price elasticities indicated a number of substitute and complementary relationships, with these relationships changing in magnitude across years. Taken together, the results suggest that any attempts to economically manage the resource should be based on multi-product production theory, not single-species biological response functions. Besides ruling out single-species management, the dominance of substitute relationships in the Mauritanian cephalopod fishery precludes the use of "key species" management of the entire resource.Research and Development/Tech Change/Emerging Technologies, Resource /Energy Economics and Policy,

Numerical simulation of InGaN Schottky solar cell

The Indium Gallium Nitride (InGaN) III-Nitride ternary alloy has the potentiality to allow achieving high efficiency solar cells through the tuning of its band gap by changing the Indium composition. It also counts among its advantages a relatively low effective mass, high carriers\^a mobility, a high absorption coefficient along with good radiation tolerance.However, the main drawback of InGaN is linked to its p-type doping, which is difficult to grow in good quality and on which ohmic contacts are difficult to realize. The Schottky solar cell is a good alternative to avoid the p-type doping of InGaN. In this report, a comprehensive numerical simulation, using mathematically rigorous optimization approach based on state-of-the-art optimization algorithms, is used to find the optimum geometrical and physical parameters that yield the best efficiency of a Schottky solar cell within the achievable device fabrication range. A 18.2% efficiency is predicted for this new InGaN solar cell design

TECHNOLOGY AND MANAGEMENT IN MAURITANIAN CEPHALOPOD FISHERIES

If the technology in a multi-species fishery is such that there is jointness in inputs and non-separability between inputs and outputs, then management on a species-by-species basis may lead to unintended outcomes, including over-exploitation of the resource. This study investigates the nature of the technical and economic relationships underlying the 1989-90 Mauritanian cephalopod fishery by estimating a system of dual output supply functions derived from a generalized Leontief revenue function. Model results indicate the existence of jointness in inputs and non-separability between inputs and outputs in the fishery. Cross-price elasticities indicated a number of substitute and complementary relationships, with these relationships changing in magnitude across years. Taken together, the results suggest that any attempts to economically manage the resource should be based on multi-product product production theory, not single-species biological response functions. Besides ruling out single-species management, the dominance of substitute relationships in the Mauritanian cephalopod fishery precludes the use of "key species" management of the entire resource.Resource /Energy Economics and Policy,

Effect of Activity-Based Costing on Profitability of Healthcare Services in Lebanese Private Hospitals Applied case study: Jabal-Amel hospital

ВЛИЯНИЕ УЧЕТА ЗАТРАТ НА РЕНТАБЕЛЬНОСТЬ МЕДИЦИНСКИХ УСЛУГ В ЛИВАНСКИХ ЧАСТНЫХ БОЛЬНИЦАХ ПРИКЛАДНОЕ ТЕМАТИЧЕСКОЕ ИССЛЕДОВАНИЕ: БОЛЬНИЦА ДЖАБАЛЬ-АМЕЛЬ Ф. ХАМАДИNowadays, activity-based-costing (ABC) system is one of the most dilemmatic systems discussed as method to achieve such objectives for hospitals, where the implementation of ABC system in hospitals provided a more accurate cost allocation of costs to the provided services by these hospitals. Considering that the Lebanese government, which pay more than 80% of the bills of healthcare services, pre-state the tariffs of healthcare services based on the estimated cost of services that is computed by the traditional cost accounting systems. This study aims to explore the effect of ABC implementation on the profitability of each healthcare service in Lebanese private hospitals. The study includes a case study for Jabal-Amel hospital in Lebanon.= На примере частной больницы Ливана сравниваются различные системы калькулировния себестоимости медицинских услуг – традиционная и АВС-система. Показан метод достижения целей по рентабельности предоставляемых медицинских услуг больницами, где внедрение АВС-системы калькулировния обеспечило бы более точное распределение затрат на предоставляемые ими услуги. При этом следует учитывать, что правительство Ливана оплачивает более 80% счетов за медицинские услуги, предварительно устанавливая тарифы на основе сметной стоимости услуг, которая рассчитывается с помощью традиционных систем учета затрат. Исследование направлено на изучение влияния внедрения рассматриваемой АВС-системы калькуляции на рентабельность каждой медицинской услуги в ливанских частных больницах, например в больнице Джабаль-Амель в Ливане