Measurement of the shot noise in a single electron transistor

We have systematically measured the shot noise in a single electron transistor (SET) as a function of bias and gate voltages. By embedding a SET in a resonance circuit we have been able to measure its shot noise at the resonance frequency 464 MHz, where the 1/f noise is negligible. We can extract the Fano factor which varies between 0.5 and 1 depending on the amount of Coulomb blockade in the SET, in very good agreement with the theory.Comment: 4 figure

CONSUMERS' WILLINGNESS TO PURCHASE LOCALLY PRODUCED AGRICULTURAL PRODUCTS: AN ANALYSIS OF AN INDIANA SURVEY

Using a survey of over 320 consumers from across the state of Indiana, we estimate an ordered probit model to determine the demographic and attitudinal factors which are most important in predicting the likelihood of consumers to purchase products that are produced within the state. Our results indicate that the willingness to purchase locally produced agricultural products increases with time of residency in the state, and we find a greater tendency for female consumers to purchase such products. We also find that quality perceptions play a critical role in these food purchase-decisions. We underscore the importance of maintaining minimum quality standards to maximize the effectiveness of state level agricultural promotion programs.Consumer/Household Economics,

Distribución espacial de la vulnerabilidad futura bajo escenario de cambio climático. Serie 3. Análisis municipal para Corredor Seco hondureño.

Mediante la prospectiva estratégica y la ciencia de los datos, se puede dibujar diferentes trayectorias del impacto futuro al sistema agrícola hondureño en respuesta al cambio climático. Los escenarios proyectan tendencias negativas en los cultivos básicos en la demanda de los hogares y cultivos con gran valor comercial. El cambio climático afectaría la aptitud de los territorios para la siembra de cultivos de alta importancia en la dieta local. Esto podría influir en la distribución del suelo y el ordenamiento del espacio rural. La vulnerabilidad en el Corredor Seco en el futuro presentaría patrones claros de aglomeración. Entendiendo que estos fenómenos indeseables pueden ser persistentes en el tiempo, se demandaría una política integral que armonice las acciones locales y nacionales, coordinando el actuar de múltiples instituciones publico privadas en la región del Corredor Seco.Through the strategic prospect and data science, different trajectories of the future impact on the Honduran agricultural system can be drawn in response to climate change. The scenarios project negative trends in basic crops in the demand of households and crops with great commercial value. Climate change would affect the territories' ability to plant crops of high importance in the local diet. This could influence the distribution of land and the arrangement of rural space. Vulnerability in the Dry Corridor in the future would present clear agglomeration patterns. Understanding that these undesirable climatic events can be persistent over time, a comprehensive policy that harmonizes local and national actions would be demanded, coordinating the actions of multiple public-private institutions in the Dry Corridor regio

De los escenarios a las trayectorias de desarrollo para la seguridad alimentaria bajo cambio climático en Honduras. Serie 1. Impacto Nacional

Los escenarios futuros son una excelente oportunidad de capturar las principales preocupaciones de los múltiples actores de una región. Al igual que contribuir con las discusiones orientadas a la priorización y planeación de sus intervenciones. Los escenarios futuros dibujan una potencial vulnerabilidad del sistema nacional de alimentos bajo dos estrategias de estímulo al sector agrícola, comercial y asociado a seguridad alimentaria. Toda vez que las condiciones climáticas futuras exacerbarían las productividades, el uso del suelo y el posicionamiento en el comercio mundial. Dada las características de la dieta, la geografía económica y los procesos de urbanización, los escenarios en su capacidad de simplificación dejan entrever la necesidad de estimular y desarrollar las capacidades de adaptación local. Para ello, el rol de las instituciones y en general de todos los involucrados en ejercicios de prospectiva estratégica, reduce la incertidumbre futura y mejora la priorización de las acciones colectivas.Future scenarios are an excellent opportunity to capture the main concerns of the multiple actors in a region. As well as contributing to the discussions aimed at prioritizing and planning their interventions. Future scenarios draw a potential vulnerability of the national food system under two strategies to stimulate the agricultural, commercial and food security sector. Since future weather conditions would exacerbate productivity, land use and position in world trade. Given the characteristics of the diet, economic geography and urbanization processes, the scenarios in their capacity for simplification suggest the need to stimulate and develop local adaptation capacities. For this, the role of institutions and in general of all those involved in strategic prospective exercises reduces future uncertainty and improves the prioritization of collective actions

El espacio de las capacidades de adaptación a nivel municipal frente al cambio climático. Serie 2. Análisis local para el Corredor Seco hondureño.

La adaptación al cambio climático a nivel local es un asunto prioridad, especialmente en regiones vulnerables como el corredor seco de Honduras. El desarrollo humano de los municipios del corredor seco configura unos patrones aglomerados de alto y bajo desarrollo. Los cuales han sido persistentes en el tiempo, manteniendo cierta desigualdad entre unos y otros. El indicador de las capacidades de adaptación al cambio climático (CCVA) refleja una importante debilidad en la respuesta municipal al integrar el vector de las variables (educación, infraestructura, gobernanza, etc.). Este desempeño evidencia un espacio regional desigual en el indicador, encontrando aglomeraciones de municipios con alto y bajo CCVA. La multidimensionalidad de la adaptación al cambio climático demanda una intervención nacional y local. Esta última mediante los planes de desarrollo municipal donde se prioricen los aspectos menos valorados en el indicador. Adaptation to climate change at a local level is a priority issue, especially in vulnerable regions such as the Dry Corridor of Honduras. The human development of the municipalities of the Dry Corridor configures agglomerated patterns of high and low development. Which have been persistent over time, maintaining some inequality between them.The indicator of climate change adaptation capacities (CCVA) reflects an important weakness in the municipal response by integrating the vector of the variables (education, infrastructure, governance, etc.). This performance shows an unequal regional space in the indicator, finding agglomerations of municipalities with high and low CCVA. The multidimensionality of adaptation to climate change demands national and local intervention. The latter through municipal development plans that prioritize the aspects less valued in the indicator

Electroweak Physics, Experimental Aspects

Collider measurements on electroweak physics are summarised. Although the precision on some observables is very high, no deviation from the Standard Model of electroweak interactions is observed. The data allow to set stringent limits on some models for new physics.Comment: Plenary Talk at the UK Phenomenology Workshop on Collider Physics, Durham, 199

Improving bean yields

Breakthroughs in plant breeding at the CGIAR have placed bean yields on a 2%-3.3% per year growth trajectory based on experiment station trials, comfortably above minimum thresholds (set, for example, by the CGIAR Excellence in Breeding (EiB) platform) required to meet the dietary requirements of a global population projected to surpass 10 billion by 2050. These on-station gains must be extended to farmers' fields

Beans: a crop to invest in

From both an economic and nutritional perspective, the common bean is under-represented in the diets of low-income populations. This shortfall is reflected in high bean prices and chronic deficiencies in protein and key nutrients, seen across the developing world. Future demand for beans, meanwhile, is projected to increase, as incomes rise and rural-urban migration increases. Investment in the development of common bean varieties and value chains has the potential to offer substantial food security and economic benefits to these populations

Future bean demand

Bean demand is projected to rise sharply throughout the developing world, in tandem with rising populations, both in absolute terms and relative to other staple crops. The surge will be especially pronounced in Sub-Saharan Africa, where population is projected to surpass 2.5 billion by 2050

Polychromatic solitons in a quadratic medium

We introduce the simplest model to describe parametric interactions in a quadratically nonlinear optical medium with the fundamental harmonic containing two components with (slightly) different carrier frequencies [which is a direct analog of wavelength-division multiplexed (WDM) models, well known in media with cubic nonlinearity]. The model takes a closed form with three different second-harmonic components, and it is formulated in the spatial domain. We demonstrate that the model supports both polychromatic solitons (PCSs), with all the components present in them, and two types of mutually orthogonal simple solitons, both types being stable in a broad parametric region. An essential peculiarity of PCS is that its power is much smaller than that of a simple (usual) soliton (taken at the same values of control parameters), which may be an advantage for experimental generation of PCSs. Collisions between the orthogonal simple solitons are simulated in detail, leading to the conclusion that the collisions are strongly inelastic, converting the simple solitons into polychromatic ones, and generating one or two additional PCSs. A collision velocity at which the inelastic effects are strongest is identified, and it is demonstrated that the collision may be used as a basis to design a simple all-optical XOR logic gate.Comment: 9 pages, 8 figures, accepted to Phys. Rev.