Predicting socioeconomic indicators using transfer learning on imagery data: an application in Brazil.

Censuses and other surveys responsible for gathering socioeconomic data are expensive and time consuming. For this reason, in poor and developing countries there often is a long gap between these surveys, which hinders the appropriate formulation of public policies as well as the development of researches. One possible approach to overcome this challenge for some socioeconomic indicators is to use satellite imagery to estimate these variables, although it is not possible to replace demographic census surveys completely due to its territorial coverage, level of disaggregation of information and large set of information. Even though using orbital images properly requires, at least, a basic remote sensing knowledge level, these images have the advantage of being commonly free and easy to access. In this paper, we use daytime and nighttime satellite imagery and apply a transfer learning technique to estimate average income, GDP per capita and a constructed water index at the city level in two Brazilian states, Bahia and Rio Grande do Sul. The transfer learning approach could explain up to 64% of the variation in city-level variables depending on the state and variable. Although data from different countries may be considerably different, results are consistent with the literature and encouraging as it is a first analysis of its kind for Brazil.

A Giant Kidney Stone in a 50-Year-Old Mayan Gardener From the Yucatan Peninsula: A Case Report.

Urolithiasis is a prevalent urological condition characterized by stone formation in the urinary tract, but stones weighing more than 100 g are rare. The Mayan and Mestizo populations in Yucatan have been identified as being at an increased risk of urolithiasis because of the coexistence of environmental, genetic, metabolic, and lifestyle risk factors. The patient's occupation may play a significant role in enhancing these factors. Here, we report the case of a Mayan gardener with a giant kidney stone weighing 1,154 g, one of the largest ever reported from Mexico.

Incidente vial relacionado con trabajo en transportadores de pasajeros y carga en Medellín Colombia: el rol de la infraestructura / Work-related crashes suffered by drivers in freight and passengers transportation activities Medellín Colombia: the road infrastructure role

RESUMEN Objetivo Analizar posibles relaciones entre infraestructura y ocurrencia de incidentes viales relacionados con el trabajo en transportadores de pasajeros y carga en Medellín entre el 2010 y el 2014. Métodos Estudio transversal de asociación entre infraestructura de incidentes viales durante el trabajo relacionados con lesiones de conductores, según la base de datos de informes policiales de accidentes de tránsito del 1.° de enero de 2010 al 31 de julio de 2014. Resultados Hubo 102 602 registros de incidentes viales relacionados con trabajo. El análisis multivariado fue posible con 8 516 registros con información completa entre marzo y julio de 2014. Los factores asociados al evento fueron: choque contra otro vehículo (RP 1,31 IC95 1,09-1,57); vías de dos carriles (RP 1,21 IC95 1,14-1,33) y de tres (RP 1,39 IC95 1,09-1,76); ser conductor de 18 a 24 años (RP 1,13 IC95 1,02-1,26); y conducir bajo efecto de alcohol (RP 2,81 IC95 2,42-3,26). Además, fueron identificados mediante análisis de información geográfica algunos puntos críticos de ocurrencia de incidentes viales relacionados con trabajo. Conclusiones Hay una tendencia creciente de incidentes viales relacionados con trabajo en Medellín. Se requiere especial atención al transporte de pasajeros y de carga por su representativo aporte al total de incidentes viales. El monitoreo de la infraestructura y de zonas de mayor incidencia puede ser útil en el diseño de programas de prevención en empresas de transporte.

ABSTRACT Objective To analyze associations between road infrastructure and Work-Related traffic accidents, in Medellin 2010-2014 in freight and passenger drivers. Methods A retrospective cross-sectional study to establish a possible association between road infrastructure and work-related traffic accidents with injuries for the driver in Medellín Colombia, using the Police traffic accident database, from January 2010 to July 2014. Results There were 102 602 records of traffic accidents. The multivariate analysis was conducted with 8516 records with complete information from March to July 2014. The factors associated with injury were: collision with another vehicle (PR 1,31 95CI 1,09-1,57); two-lane roads (PR: 1,21, 95% CI 1,14-1,33) and three-lane roads (PR: 1,39, 95CI 1,091,76); being a driver between 18 and 24 years old (PR 1.13 95 CI 1,02-1,26); and driving under the influence of alcohol (PR: 2,81 95% CI 2,42-3,26). In addition, through analysis of geographic information, critical points of work-related crashes were identified. Conclusion A growing trend of work-related traffic accidents was identified in Medellín. Special attention must be addressed to passenger and cargo transport due to its significant contribution to traffic accidents in the city. The monitoring of infrastructure and areas with the highest inci-dence can be useful in the design of prevention programs in transport companies.

Holding on to a shifting substrate: plasticity of egg mass tethers and tethering forces in soft sediment for an intertidal gastropod.

Staying attached at a favorable site can be a major challenge for organisms in flow. Meeting this challenge depends on properties of the attachment structure and substrate, the nature of fluid flow, and the ability to adjust attachment force in response to hydrodynamic conditions. A broad taxonomic range of adult stages use adhesion or suction to attach to hard substrates in intertidal habitats, which experience flow from waves and tidal currents. We address the unique challenges of attachment to soft sediment in reproductive structures deposited on tidal flats. Egg masses of the opisthobranch mollusc Melanochlamys diomedea are anchored to the sediment by a buried tether composed of gel and sediment. In the field, populations differed in absolute tethering force and tethering force per unit size (= tenacity). Population differences in tenacity persisted for egg masses oviposited under common conditions in the laboratory. Adults exposed to greater flow produced tethers with greater tenacity but without an increase in tether size. Tethers tended to fail by slippage rather than breakage, indicating that tethering force depends more on frictional interaction with sediment than on strength of the tether axis. These results suggest that adults respond to variation in risks of embryo dislodgment by adjusting the tethering properties of egg masses, and that these adjustments involve more than simple changes in tether length or mass.