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No Entiendo: The Effects of Bilingualism on Hispanic Earnings
This paper examines whether the ability to communicate in English and Spanish is rewarded in labor markets. Using data from the 2000 U.S. Census we find that among Hispanics, earnings are higher as the ability to speak English increases. We also find that bilingualism, is associated with higher wages reversing the negative effect found in earlier studies. The reversal could be explained by increasing immigration, and from economic integration with Latin America. Our results also show that bilingualism is negatively correlated with wages among different occupational categories and sectors, but particularly among managers and those employed in the public sector
The atlantic side of the iberian peninsula: a hot-spot of novel maternal honey bee diversity
The Iberian Peninsula harbors one the highest mitocondrial DNA (mtDNA) diversity ever reported for honey bee subspecies. This finding is explained not only by the co-occurrence of two divergent evolutionary lineages, western European (lineage M) and African (lineage A), but also by the higher variability of African and western European haplotypes. Indeed, over 36 haplotypes of western European and African ancestry, which form complex networks, have been reported for this area of the honey bee natural range. While studies on the diversity patterns of central and Mediterranean Iberian populations are abundant, the genetic composition of populations inhabiting the Atlantic side was until recently virtually unknown. Using the popular DraI test (PCR amplification and restriction of the intergenic tRNAleu-coxII region) we performed a fine scale genetic survey of the honey bee populations from Portugal. Adding to the 24 previously described African haplotypes, of which 17 are found in the Iberian Peninsula, 13 unreported haplotypes of African ancestry were found in our survey, which represent an addition of 54% of new variation. The fragment sizes ranged from approximately 800 to 1200 bp and the restriction length of the new haplotypes were very distinct from those reported in the literature. To further confirm the novelty of these haplotypes, we sequenced the aforementioned mtDNA region. Herein we present a phylogenetic analysis of these novel haplotypes
Patrón espacial de la variación molecular de Apis mellifera en Gran Canaria y la Gomera (Islas Canarias)
Las islas del Archipiélago Canario presentan condiciones ambientales variables según
su altitud, latitud y longitud, lo cual influye en la distribución de los organismos. En
relación con la abeja de la miel (Apis mellifera L.), estudios previas realizados por De la
Rúa et a I. ( 1998) Y por Padilla-Álvarez et al. (1998), sugieren la existencia en las Islas
Canarias de poblaciones que han evolucionado de una forma relativamente aislada y
que se han adaptado en cada isla a unas determinadas condiciones ambientales. Las
abejas canarias fueron incluí das en un sublinaje de distribución atlántica (AIII) del
linaje evolutivo africano, en el cual se circunscriben las poblaciones de abejas de los
Archipiélagos Maearonésicos (Islas Azores, Madeira, Islas Salvajes, Islas Canarias y
Cabo Verde) y de Portugal. En el presente trabajo se presentan los resultados del estudio
de la variabilidad molecular al nivel mitocondrial (ADNmt), de las poblaciones de
abejas de la miel en las islas canarias de Gran Canaria y La Gomera mediante el análisis
de la región intergénica del ADNmt comprendida entre los genes del ARN transferente
de la leucina (ARNtleu) y la subunidad II de la citocromo oxidasa (cox2). Este
marcador es adecuado para estimar la diversidad genética y los patrones de
diferenciación espacial, en relación con la variedad ambiental existente en las islas de
Gran Canaria y La Gomera
INFLUENCE OF ANKLE PASSIVE RANGE OF MOTION ON THE PERFORMANCE OF THE STAR EXCURSION BALANCE TEST
The purpose of this study was to measure the association between ankle passive range of motion (PROM) and the horizontal distance reached during the Star Excursion Balance Test (SEBT). Nineteen participants without any musculoskeletal and neurological injury performed the SEBT on eight directions proposed in the original protocol. The ankle PROM was measured with a manual goniometric device prior to the performance of the test. To determine the association between the distance reached during SEBT and the ankle PROM, we used the Pearson Correlation Coefficient Test (“r”). All directions of SEBT showed low correlation with the ankle PROM without significant differences for any variable. We concluded that the ankle PROM is not a
confounding variable that should be monitored for use the SEBT for healthy individuals
Design of a low cost weather station for detecting environmental changes
El objetivo de esta investigación es desarrollar un
prototipo de estación meteorológica secundaria para
mediciones de temperatura, humedad y presión
atmosférica. Para validar la operación, se realizó un
análisis de varianza y un diseño experimental r&R. Los
sensores TMP36, RHT03 y BMP085 fueron seleccionados
para la plataforma Arduino UNO y calibrados con una
estación meteorológica y un higrómetro digital
certificado por las autoridades. Nuestro sistema utiliza
hardware y software abiertos y es una estación
meteorológica de bajo costo diseñada para el análisis
ambiental.The aim of this research is to develop a secondary weather station prototype for measurements of temperature, humidity and atmospheric pressure. To validate the operation, a variance analysis and an experimental design r&R were conducted. The TMP36, RHT03 and BMP085 sensors were selected for Arduino UNO platform and calibrated with a weather station and a digital hygrometer certifies by the authorities. Our system uses open hardware and software and is a low cost weather station designed for environmental analysi
Polymorphisms in cytochrome P450 versus cline distribution of evolutionary lineages in Apis mellifera iberiensis
Honey bees (Apis mellifera) are the most prominent and economically important pollinator species worldwide. However, the reported decline of its populations in several regions of the world over the last decades is of concern. The causes are manifold, including the spread of pathogens and parasites, malnutrition and habitat loss, climate change and xenobiotics, especially pesticides. Among the main mechanisms used by insects to cope with the adverse effects of xenobiotics is the metabolic resistance mediated mainly by three superfamilies of enzymes: the cytochrome P450 monooxygenases, the glutathione transferases and the carboxylesterases.
We hypothesize that the genetic background influences the sensitivity to pesticides or detoxification capacity of different honey bee populations, ecotypes and subspecies. The Iberian Peninsula provides an interesting scenario to study the genetic variability of the cytochrome P450 genes given the co-occurrence of two clinally distributed evolutionary lineages, as a result of secondary contact.
In this study, the genetic variability of six genes of the cytochrome P450 superfamily (CYP6AS3, CYP6AS4, CYP6AS5, CYP6AS7, CYP6AS12 and CYP6AS17) was analyzed in the Iberian honey bee (Apis mellifera iberiensis) to provide more information on the mechanisms of resistance to xenobiotics and to identify the genetic variation involved in local adaptation. Genomic signal of selective sweeps was detected in three genes, of which CYP6AS5 presents the highest number of point mutations under selection, being proposed as a candidate gene to perform gene expression studies. We discuss the correlation between the variability of P450 genes and the distribution of the evolutionary lineages in the Iberian Peninsula. The identification of polymorphisms in these genes promises to shed light on the relationship between diversity and xenobiotic tolerance of A. m. iberiensis.info:eu-repo/semantics/publishedVersio
Logística reversa : oportunidade para redução de custos através do gerenciamento da cadeia integrada de valor
O artigo discorre sobre um aspecto da Logística que só agora começa a
ser olhado mais atentamente pelas empresas. Enquanto a logística tradicional trata
do fluxo de saída dos produtos, a Logística Reversa tem que se preocupar com o
retorno de produtos, materiais e peças ao processo de produção da empresa.
Devido a legislações ambientais mais severas e maior consciência por parte dos
consumidores, as empresas estão não só utilizando uma maior quantidade de
materiais reciclados como também tendo que se preocupar com o descarte
ecologicamente correto de seus produtos ao final de seu ciclo de vida. Além disto,
muitas firmas têm feito da Logística Reversa uma arma estratégica em seu
planejamento de negócios. Tudo isto vem fortalecer o desenvolvimento da Logística
Reversa nas empresas. E no caso brasileiro de acordos a especialistas de logística
reversa esta área vem sendo considerada como um elemento importante no
planejamento estratégico das organizações para adequá-las à legislação do meio
ambiente atual. O trabalho vem mostrar oportunidades em redução de custos
através do gerenciamento da cadeia de valor da empresa, com o envolvimento de
todos os componentes. O método utilizado é o de estudo de caso em uma empresa
do setor de refrigerantes
Applying an unified access control for IoT-based Intelligent Agent Systems
IEEE 8th International Conference on Service-Oriented Computing and Applications (SOCA), 19/10/2015-21/10/2015, Roma, ItaliaThe rise of the Internet of Things (IoT) paradigm
has allowed the design and development of new services interconnecting
heterogeneous devices. However, the complexity
of these new systems hasn"t been followed by the increase of
intelligence and reasoning of the devices connected. On the
other hand, intelligent agent systems have developed precisely
these characteristics so the combination of both paradigms by
modelling intelligent agents in IoT devices is a very promising
approach that will enable a more powerful and smart IoT. The interconnection
of agents through a Internet-based network implies
addressing critical issues that affect all network communications,
such as security, privacy and access control, specially given the
sensitivity of the information exchanged by agents. In this paper,
we propose the application of User-Managed Access (UMA) to
provide an unified access control schema for an heterogeneous
hybrid architecture of IoT devices and intelligent agents.Ministerio de Economía y Competitivida
Intelligent Traffic Light Management using Multi-Behavioral Agents
XIII Jornadas de Ingeniería Telemática,
27/09/2017-29/09/2017, Valencia, EspañaOne of the biggest challenges in modern societies is to solve vehicular traffic problems. In this scenario, our proposal is to use a Multi-Agent Systems (MAS) composed of three types of agent: traffic light management agents, traffic jam detection agents, and agents that control the traffic lights at an intersection. This third type of agent is able to change its behaviour between what we have called a selfish mode (the agent will try to influence the other neighbour agents of its type to achieve its goal) or an altruistic mode (the agent will take into consideration the other neighbour selfish agents indications). To validate our solution, we have developed a MAS emulator which communicates with the Simulation of Urban MObility (SUMO) traffic simulator using the Traci tool to realize the experiments in a realistic environment. The obtained results show that our proposal is able to improve other existing solutions such as conventional traffic light management systems (static or dynamic) in terms of reduction of vehicle trip duration
Access Control Mechanism for IoT Environments Based on Modelling Communication Procedures as Resources
Internet growth has generated new types of services where the use of sensors and actuators is especially remarkable. These services compose what is known as the Internet of Things (IoT). One of the biggest current challenges is obtaining a safe and easy access control scheme for the data managed in these services. We propose integrating IoT devices in an access control system designed for Web-based services by modelling certain IoT communication elements as resources. This would allow us to obtain a unified access control scheme between heterogeneous devices (IoT devices, Internet-based services, etc.). To achieve this, we have analysed the most relevant communication protocols for these kinds of environments and then we have proposed a methodology which allows the modelling of communication actions as resources. Then, we can protect these resources using access control mechanisms. The validation of our proposal has been carried out by selecting a communication protocol based on message exchange, specifically Message Queuing Telemetry Transport (MQTT). As an access control scheme, we have selected User-Managed Access (UMA), an existing Open Authorization (OAuth) 2.0 profile originally developed for the protection of Internet services. We have performed tests focused on validating the proposed solution in terms of the correctness of the access control system. Finally, we have evaluated the energy consumption overhead when using our proposal.Ministerio de Economía y CompetitividadUniversidad de Alcal
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