Mexican Agricultural and Food Export Competitiveness

This report analyzes the export performance of the Mexican agricultural and food sector in recent years with a particular emphasis on the changing competitiveness of those exports in the U.S. and world markets. The report includes an examination of the general trends in Mexican agricultural and food exports, an analysis of the international competitiveness of the major subgroups of Mexican agriculture based on the Revealed Comparative Advantage methodology, an assessment of the competitiveness of Mexican exports of specific agricultural and food products to the United States, a consideration of the effectiveness of Mexico’s agricultural and food export market diversification efforts, a discussion of the main factors likely to affect the long-term competitiveness of Mexican agriculture, and policy recommendations for enhancing the competitiveness of Mexican agricultural and food exports.Mexican, Exports, Food Export, Mexican Food, Competitiveness, International Development, International Relations/Trade,

Solar System Modeler: A Distributed, Virtual Environment for Space Visualization and GPS Navigation

The Solar System Modeler (SM) extends the Space Modeler developed in 1994. It provides a virtual environment enabling an explorer to dynamically investigate near Earth satellites, deep space probes, planets, moons, and other celestial phenomena. The explorer navigates the virtual environment via mouse selected options from menu panels while wearing a tracked, head mounted display (HMD). Alternatively, a monitor may replace the HMD and keyboard controls replace head tracking. The SM\u27s functionality is extended by the ability to broadcast simulated GPS satellite transmissions in compliance with Distributed Interactive Simulation (DIS) protocol standards. The transmissions include information found in true GPS broadcasts that is required for a receiver to determine its location. The Virtual GPS Receiver (VGPSR) receives the GPS transmissions from the SM and computes the receiver\u27s position with a realistic error based on numerous variables simulating those encountered in the real GPS system. The VGPSR is designed as a plug-in module for simulations requiring virtual navigation. The receiver\u27s client application provides the VGPSR with the simulation time and the true position of the receiver. In return, the application receives a GPS indicated position

Vortex Fluctuations in the Critical Casimir Effect of Superfluid and Superconducting Films

Vortex-loop renormalization techniques are used to calculate the magnitude of the critical Casimir forces in superfluid films. The force is found to become appreciable when size of the thermal vortex loops is comparable to the film thickness, and the results for T < Tc are found to match very well with perturbative renormalization theories that have only been carried out for T > Tc. When applied to a high-Tc superconducting film connected to a bulk sample, the Casimir force causes a voltage difference to appear between the film and bulk, and estimates show that this may be readily measurable.Comment: 4 pages, 5 figures, Revtex 4, typo correctio

Mexican agricultural export competitiveness

This article analyzes the export performance of the Mexican agricultural and food sector in recent years with emphasis on the changing competitiveness of those exports in the U.S. and world markets. The paper includes an examination of the general trends in Mexican agricultural and food exports, an analysis of the international competitiveness of the major subgroups of Mexican agriculture based on the Revealed Comparative Advantage methodology, an assessment of the competitiveness of Mexican exports of specific agricultural and food products to the United States, and a consideration of the effectiveness of Mexico's agricultural and food export market diversification efforts.Mexico, export, competitiveness, agricultural., Agribusiness,

SOCIAL WELFARE AND ENVIRONMENTAL DEGRADATION IN AGRICULTURE: THE CASE OF ECUADOR

A non-linear optimization model which maximizes total Ecuadorian social welfare, defined as the sum of consumers' and producers' surpluses for the four major crops (corn, bananas, rice and African palm) is developed to evaluate the tradeoff between welfare and environmental degradation in Ecuador. It was found that a total welfare loss of US$122 million (a 11 percent reduction - from US$ 1.112 billion to US$ 989.66 million) would be expected from a 30 percent reduction in the total pesticide load on the environment in the production of the four major crops. The distributional impacts of the welfare loss were found, however, to be significantly skewed toward the loss of consumers' surplus. Specifically, a 30 percent reduction of total pesticide load on the environment would result in a reduction of 3.86 percent of producers' total surplus while consumers would be expected to loose 19.46 percent of their total surplus.welfare tradeoff, environmental impacts, non-linear optimization, Environmental Economics and Policy,

Observations and simulations of recurrent novae: U Sco and V394 CrA

Observations and analysis of the Aug. 1987 outburst of the recurrent nova V394 CrA are presented. This nova is extremely fast and its outburst characteristics closely resemble those of the recurrent nova U Sco. Hydrodynamic simulations of the outbursts of recurrent novae were performed. Results as applied to the outbursts of V394 CrA and U Sco are summarized

Ultraviolet observations of LMC nova 1988

The IUE obtained ultraviolet spectra of a nova in an external galaxy. The spectral features do not seem unusual for a nova at maximum but it is hoped to be able to follow it for a long enough time to be able to study the high ionization lines that appear when the density drops to lower values (the nebular stage). A high dispersion spectrum was also obtained to assist in the line identification and to study the line of sight to the LMC 1 deg of arc away from SN 1987A

Continuous infusion of an agonist of the tumor necrosis factor receptor 2 in the spinal cord improves recovery after traumatic contusive injury.

AimThe activation of the TNFR2 receptor is beneficial in several pathologies of the central nervous system, and this study examines whether it can ameliorate the recovery process following spinal cord injury.MethodsEHD2-sc-mTNFR2 , an agonist specific for TNFR2, was used to treat neurons exposed to high levels of glutamate in vitro. In vivo, it was infused directly to the spinal cord via osmotic pumps immediately after a contusion to the cord at the T9 level. Locomotion behavior was assessed for 6 weeks, and the tissue was analyzed (lesion size, RNA and protein expression, cell death) after injury. Somatosensory evoked potentials were also measured in response to hindlimb stimulation.ResultsThe activation of TNFR2 protected neurons from glutamate-mediated excitotoxicity through the activation of phosphoinositide-3 kinase gamma in vitro and improved the locomotion of animals following spinal cord injury. The extent of the injury was not affected by infusing EHD2-sc-mTNFR2 , but higher levels of neurofilament H and 2', 3'-cyclic-nucleotide 3'-phosphodiesterase were observed 6 weeks after the injury. Finally, the activation of TNFR2 after injury increased the neural response recorded in the cortex following hindlimb stimulation.ConclusionThe activation of TNFR2 in the spinal cord following contusive injury leads to enhanced locomotion and better cortical responses to hindlimb stimulation

Observations and simulations of nova Vul 1984 no. 2: A nova with ejecta rich in oxygen, neon, and magnesium

Nova Vul 1984 no. 2 was observed with IUE from Dec. 1984 through Nov. 1987. The spectra are characterized by strong lines from Mg, Ne, C, Si, O, N, and other elements. Data obtained in the ultraviolet, infrared, and optical show that this nova is ejecting material rich in oxygen, neon, and magnesium

Optical and ultraviolet observations of nova Vul 1987

The outburst for a nova discovered in Nov. 1987 and followed since then is summarized. Although it was possible to observe it with the IUE at maximum, its ultraviolet energy faded rapidly, and after the first 2 weeks it was impossible to observe it at IUE wavelengths. It is observed to form a thick dust shell and is in the nebular stage