Choices under Risk in Rural Peru

This paper estimates the risk preferences of cotton farmers in Southern Peru, using the results from a multiple-price-list lottery game. Assuming that preferences conform to two of the leading models of decision under risk--Expected Utility Theory (EUT) and Cumulative Prospect Theory (CPT)--we find strong evidence of moderate risk aversion. Once we include individual characteristics in the estimation of risk parameters, we observe that farmers use subjective nonlinear probability weighting, a behavior consistent with CPT. Interestingly, when we allow for preference heterogeneity via the estimation of mixture models--where the proportion of subjects who behave according to EUT or to CPT is endogenously determined--we find that the majority of farmers' choices are best explained by CPT. We further hypothesize that the multiple switching behavior observed in our sample can be explained by nonlinear probability weighting made in a context of large random calculation mistakes; the evidence found on this regard is mixed. Finally, we find that attaining higher education is the single most important individual characteristic correlated with risk preferences, a result that suggests a connection between cognitive abilities and behavior towards risk.

Cracking Control in Mezzanine Floor Slabs using Rice Husk Ash and Polypropylene Fibers

The continuous population increase in recent years requires a greater number of households to be built quickly, with good materials and produced under quality standards that guarantee their manufacturing process. The prefabricated concrete, produced and supplied by concrete plants, is poured into the different structural elements, the mezzanine slabs being the most careful surfaces in the appearance of fissures; because being horizontal and having larger dimensions, the dimensional changes in the concrete appear more frequently due to the rapid loss of water from the surface of the concrete before setting; which generates superior stresses to the resistant capacity of the concrete at early ages, which affect the durability and reduce the resistance of the structures, causing greater economic expenses in maintenance and repairs. In the present investigation, 5%, 10% and 15% of rice husk ash was used as a replacement for cement and 900g/m3 of polypropylene fiber; The results indicate that as the percentage of rice husk ash increases, there is a reduction in the slump and the crack fissures, and that the resistance to compression and flexion decreases, with respect to the concrete pattern

Wavelength calibration of the JWST-MIRI medium resolution spectrometer

We present the wavelength and spectral resolution characterisation of the Integral Field Unit (IFU) Medium Resolution Spectrometer for the Mid-InfraRed Instrument (MIRI), to fly onboard the James Webb Space Telescope in 2014. We use data collected using the Verification Model of the instrument and develop an empirical method to calibrate properties such as wavelength range and resolving power in a portion of the spectrometer's full spectral range (5-28 microns). We test our results against optical models to verify the system requirements and combine them with a study of the fringing pattern in the instrument's detector to provide a more accurate calibration. We show that MIRI's IFU spectrometer will be able to produce spectra with a resolving power above R=2800 in the wavelength range 6.46-7.70 microns, and that the unresolved spectral lines are well fitted by a Gaussian profile.Comment: 12 pages, submitted to SPIE Proceedings vol. 7731, Space Telescopes and Instrumentation 2010: Optical, Infrared, and Millimeter Wav

Dynamic Field Experiments in Development Economics: Risk Valuation in Morocco, Kenya, and Peru

The effective design and implementation of interventions that reduce vulnerability and poverty require a solid understanding of underlying poverty dynamics and associated behavioral responses. Stochastic and dynamic benefit streams can make it difficult for the poor to learn the value of such interventions to them. We explore how dynamic field experiments can help (i) intended beneficiaries to learn and understand these complicated benefit streams, and (ii) researchers to better understand how the poor respond to risk when faced with nonlinear welfare dynamics. We discuss and analyze dynamic risk valuation experiments in Morocco, Peru, and Kenya.poverty, risk and uncertainty, dynamics, experiments, Kenya, Morocco, Peru, International Development, Research Methods/ Statistical Methods, Risk and Uncertainty,

The genetic landscape of the Iberian red deer (Cervus elaphus hispanicus) after 30 years of big-game hunting in southern Spain

© 2015 The Wildlife Society. The Iberian red deer (Cervus elaphus hispanicus) suffered a striking collapse of its populations during the first half of the 20th century due to excessive hunting. In Andalusia, southern Spain, re-colonization took place from a few relict populations through natural dispersal, and through artificial reintroductions for big-game hunting. How the population decline influenced genetic diversity, and its current distribution after the re-colonization and intensive hunting practices are unclear. We addressed these questions by analyzing nuclear microsatellite variability from 58 red deer populations distributed throughout Andalusia. Our results showed a relatively high genetic variability spatially structured into 5 clusters, corresponding to the locations of relict populations. This indicates that the red deer's current genetic background has presumably retained much of the genetic variation present in those relict populations. We also found that a substantial portion (32%) of the populations displays some degree of inbreeding. We suggest that new herds should be established using individuals from the different genetic clusters, and a careful monitoring of the breeder's genetic background to prevent further inbreeding and inadvertent hybridization. Failure to do so could lead to loss of genetic diversity and the dilution of the genetic identity of the Iberian red deer.Peer Reviewe

Innovación del proceso de soldadura de piezas de aluminio para aumentar la productividad y eficiencia en CPP Ensenada

En este trabajo se aplicó la metodología DMAIC como una herramienta de Seis Sigma para disminuir al menos en 20% el tiempo de ciclo y costo de re trabajo en una pieza de aluminio con número de parte 222xxxxx en la empresa CPP Ensenada. Durante el proyecto se implementaron cada una de las fases de la metodología DMAIC: definir, medir, analizar, mejorar y controlar; con base en ellas se determinaron las mejores prácticas, lecciones aprendidas y se implementaron las mejoras, de esta forma, se logró la disminución del tiempo de ciclo inicial de 31.47 horas hasta 11.72 horas (reducción aproximada del 62.75%), reducción en promedio del costo de re trabajo de $904 a$632 dólares por pieza fundida (reducción aproximadamente del 30.08%, con un total de ahorro de $13,438 dólares hasta la fecha del cierre del proyecto), la reducción de la cantidad de defecto de fundición de 28 a 10.5 aproximadamente (reducción de 62.5%), reducción de la cantidad de defectos de re trabajo desde 28.4 hasta 16.6 (aproximadamente disminuyó en 41.54%), aumento de la eficiencia de los soldadores hasta 90% y la reducción de DPMO fue de 162,500 hasta 45,454 (72.02%). Como actividades abiertas después del cierre del proyecto, se encuentra la aplicación de este proyecto a números de parte de nuevo ingreso, dentro de las lecciones aprendidas, se incluye aplicar el trabajo estandarizado en cada proceso para disminuir la variación y como mejores prácticas, se estableció la técnica de biselado para la correcta realización del corte.Maestri

Preliminary Results from the Experimental Study of CO2-Brine-Rock Interactions at Elevated T & P: Implications for the Pilot Plant for CO2 Storage in Spain

AbstractA new experimental program has been carried out in order to study CO2-brine-rock interactions susceptible to take place in conditions close to those expected in the pilot plant that is being developed in Spain (a carbonate reservoir located at more than 800 m depth, with 15% porosity, and a salinity of the native brine between 20 – 90g/L). The combination of preliminary experimental and numerical modeling (PHREEQC) results suggests that the main geochemical processes are calcite dissolution and anhydrite precipitation

Polyfire project- an example of an industrial research project promoting safe industrial production of fire-resistant nanocomposites

New developments based on nanotechnology have to guarantee safe products and processes to be accepted by society. The Polyfire project will develop and scale-up techniques for processing halogen-free, fire-retardant nanocomposite materials and coatings based on unsaturated polyester resins and organoclays. The project includes a work package that will assess the Health and Environmental impacts derived from the manipulation of nanoparticles. This work package includes the following tasks: (1) Identification of Health and Environment Impacts derived from the processes, (2) Experimentation to study specific Nanoparticle Emissions, (3) Development of a Risk Management Methodology for the process, and (4) A Comparison of the Health and Environmental Impact of New and Existing Materials. To date, potential exposure scenarios to nanomaterials have been identified through the development of a Preliminary Hazard Analysis (PHA) of the new production processes. In the next step, these scenarios will be studied and simulated to evaluate potential emissions of nanomaterials. Polyfire is a collaborative European project, funded by the European Commission 7th Framework Programme (Grant Agreement No 229220). It features 11 partners from 5 countries (5 SMEs, 3 research institutes, 2 large companies, 1 association) and runs for three years (1st September 2009 – 31st August 2012). This project is an example of an industrial research development which aims to introduce to the market new products promoting the safe use of nanomaterials

Relative Contribution of Different Upper Glycolytic Components in the Maintenance of the Retinal Vascular Endothelial Cell Barrier

Introduction: Damage to the retinal vascular endothelium is implicated in the progression of retinal degenerative diseases, including diabetic retinopathy (DR) and diabetic macular edema (DME). The retinal endothelial cells constitute the inner blood-retinal barrier (iBRB), and disruption of this barrier allows for the dysregulation of fluid and solute passage into the retina. Moreover, under normal physiological conditions, glycolytic metabolism is critical to the functioning of endothelial cells and maintenance of the iBRB. Conversely, in hyperglycemic environments, unregulated glycolytic metabolism leads to a buildup of glycolytic intermediates, which is thought to contribute to disruption of the iBRB and is associated with retinal cell damage and neovascularization. However, the metabolic mechanisms underlying these processes remain unclear. In this study, we looked to further characterize the roles of upper glycolytic enzymes, those involved in the ATP consumption phase of glycolysis, in the maintenance of the iBRB. Methods: Electric cell-substrate impedance sensing (ECIS) technology was used to assess in real-time the role of different glycolytic enzymes in maintaining the barrier functionality of human retinal endothelial cells (HREC). Furthermore, the endothelial cellular viability was assessed through lactate dehydrogenase cytotoxicity assay following 24h, 48h, and 72h time intervals. Results: Inhibition with heptelidic acid (glyceraldehyde-3-phosphate dehydrogenase (GA3PDH) inhibitor) significantly reduced the resistance (R) and thus the integrity of the HREC barrier at concentrations of 1.0 μM and 10 μM. PFK158 (phosphofructokinase-1 (PFK1) inhibitor) also significantly reduced R, but only at a concentration of 10 μM. Similarly, administration of PFK158 reduced HREC viability throughout all three time intervals (24h, 48h, and 72h) at a concentration of 10 μM. However, administration of heptelidic acid showed reduced HREC viability only at the 72h time interval, but also at a concentration of 10 μM. The other inhibitors tested did not demonstrate significant reduction in resistance of the HREC barrier or in cellular viability. Conclusion: Our study demonstrates the differential roles of glycolytic enzymes in maintaining the barrier functionality of HRECs. We specifically showed that the functions of GA3PDH and PFK-1 are the most important components in regulating HREC barrier integrity. These observed differences are significant since they could serve as the basis for future pharmacological and gene expression studies aiming to improve the activity of GA3PDH and PFK1 and thereby provide avenues for therapeutic modalities in endothelial-associated retinal diseases

Phase Velocity Method for Guided Wave Measurements in Composite Plates

Carbon Fiber Reinforced Polymer is a well-recognized material for aeronautic applications. Its plane structure has been widely used where anisotropic characteristics should be evaluated with flaw detection. A phase velocity method of ultrasonic guided waves based on a pitch-catch configuration is presented for this purpose. Both shear vertical (SV) and shear horizontal (SH) have been studied. For SV (Lamb waves) the measurements were done at different frequencies in order to evaluate the geometrical dispersion and elastic constants. The results for SV are discussed with an orthotropic elastic model. Finally experiments with lamination flaws are presented