Investigation into the effect of atmospheric particulate matter (PM2.5 and PM10) concentrations on GPS signals

The Global Positioning System (GPS) has been widely used in navigation, surveying, geophysical and geodynamic studies, machine guidance, etc. High-precision GPS applications such as geodetic surveying need millimeter and centimeter level accuracy. Since GPS signals are affected by atmospheric effects, methods of correcting or eliminating ionospheric and tropospheric bias are needed in GPS data processing. Relative positioning can be used to mitigate the atmospheric effect, but its efficiency depends on the baseline lengths. Air pollution is a serious problem globally, especially in developing countries that causes health problems to humans and damage to the ecosystem. Respirable suspended particles are coarse particles with a diameter of 10 micrometers or less, also known as PM10. Moreover, fine particles with a diameter of 2.5 micrometers or less are known as PM2.5. GPS signals travel through the atmosphere before arriving at receivers on the Earth’s surface, and the research question posed in this paper is: are GPS signals affected by the increased concentration of the PM2.5/PM10 particles? There is no standard model of the effect of PM2.5/PM10 particles on GPS signals in GPS data processing, although an approximate generic model of non-gaseous atmospheric constituents (<1 mm) can be found in the literature. This paper investigates the effect of the concentration of PM2.5/PM10 particles on GPS signals and validates the aforementioned approximate model with a carrier-to-noise ratio (CNR)-based empirical method. Both the approximate model and the empirical results show that the atmospheric PM2.5/PM10 particles and their concentrations have a negligible effect on GPS signals and the effect is comparable with the noise level of GPS measurements

Connecting the dots to build the future teaching and learning

This paper outlines a seven-point strategy to devise a system of continuous improvement of teacher quality and, through it, the quality of education as a whole. Education is one of the single most important initiatives that can be undertaken to improve the quality of life, financial security and economic potential of a given population. There is no disputing the benefits of a strong education system. The challenge is in the design and implementation of such a system, and creating the political will to see the system through. For such a program to be implemented, teacher quality and the quality of education as a whole must be considered a national priority. Educational and political leaders must support these initiatives publicly, place them on their policy agenda and establish a blue ribbon commission to develop a strategy to significantly and measurably improve teacher quality. The blue ribbon commission will audit the various policies and programs that influence teacher quality. By mapping these programs and their coherence, the commission will identify opportunities to increase their effectiveness and yield greater and more synergistic harmonious results. These changes can form the basis for a strategy that is sequenced and calibrated to deal with specific entry points, concerns and constraints for the region in question. The steps necessary to promote teacher professionalism may differ where there are serious shortages of teacher candidates or where chronic absenteeism is rampant, or where there is a dearth or glut of technology and infrastructure. This determination will also highlight what role the private sector or civil society can play in the education development in the region. Making teaching an attractive profession is crucial to the strategy, to ensure a constant flow of qualified applicants who can capitalize on their initial training, and take full advantage of continuous learning throughout their careers. Clear career trajectories and incentives tied to performance, as well as a system to accurately measure performance outcomes will provide a pathway to teacher professionalism. The quest for professionalism must begin at the institutions charged with teacher preparation. The blue ribbon commission should include incentives and support for these institutions, providing the support necessary to review and improve their programs to ensure the best results. Innovating the preparation of teachers is integral to the strategy. Rapidly changing societies require versatile teachers to equip their students with a dynamic array of tools to face a dynamic world. Teacher professional development must take into account this need, ensuring that the pre-service education programs align with professional standards, are goal-oriented, and include holistic, integrated and innovative projects. Technology and collaborative projects will also serve a crucial role in the pre-service education of teacher candidates, as well as the life-long development of teachers. The core of good education is a skilled and versatile teaching staff. In order to effect significant improvements to the quality of education, a cohesive strategy is required so that we can combine what we know already into an efficient system which can be implemented worldwide at the scale necessary to succeed. The dots need to be connected. Connecting the dots to build the future teaching and learning (PDF Download Available). Available from: https://www.researchgate.net/publication/314878979_Connecting_the_dots_to_build_the_future_teaching_and_learning [accessed Jan 29 2018]

Genetic dissection of photoperiod response based on GWAS of pre-anthesis phase duration in spring barley

Heading time is a complex trait, and natural variation in photoperiod responses is a major factor controlling time to heading, adaptation and grain yield. In barley, previous heading time studies have been mainly conducted under field conditions to measure total days to heading. We followed a novel approach and studied the natural variation of time to heading in a world-wide spring barley collection (218 accessions), comprising of 95 photoperiod-sensitive (Ppd-H1) and 123 accessions with reduced photoperiod sensitivity (ppd-H1) to long-day (LD) through dissecting pre-anthesis development into four major stages and sub-phases. The study was conducted under greenhouse (GH) conditions (LD; 16/8 h; ∼20/∼16°C day/night). Genotyping was performed using a genome-wide high density 9K single nucleotide polymorphisms (SNPs) chip which assayed 7842 SNPs. We used the barley physical map to identify candidate genes underlying genome-wide association scans (GWAS). GWAS for pre-anthesis stages/sub-phases in each photoperiod group provided great power for partitioning genetic effects on floral initiation and heading time. In addition to major genes known to regulate heading time under field conditions, several novel QTL with medium to high effects, including new QTL having major effects on developmental stages/sub-phases were found to be associated in this study. For example, highly associated SNPs tagged the physical regions around HvCO1 (barley CONSTANS1) and BFL (BARLEY FLORICAULA/LEAFY) genes. Based upon our GWAS analysis, we propose a new genetic network model for each photoperiod group, which includes several newly identified genes, such as several HvCO-like genes, belonging to different heading time pathways in barley

Developmental patterns of a large set of barley (Hordeum vulgare) cultivars in response to ambient temperature

Ambient temperature plays an important role in plant development. In cereals, little is known about the exact effects of ambient temperature in the range between it being a vernalising agent and an abiotic stress factor; thus the genetic determinants involved in the registering and response to ambient temperature, and their natural variation has not been dissected either. Principally, we wished to establish the level of natural variation in response to ambient temperature in barley via studying plant phenological development. The responses to temperature of 168 barley genotypes of different provenances and seasonal growth habit groups were observed in controlled environments. The effects of four temperature regimes (13◦C, 16.5◦C, 18◦C and 23◦C) on the duration of plant phenophases were examined. The plant development was characterised in a series of consecutive phenophases that span the plant life cycle from germination through flowering to attainment of maximum plant height. Ambient temperature affected significantly plant development, with substantial variation in responses among the genotypes. Six major types of responses were identified, which depended strongly on seasonal growth habit, with only a small degree of overlap. Although the differences in the timing of development among clusters were significant under each temperature regime, the 23◦C treatment resulted in the largest diversity of responses, with significant changes in the ranking of the six clusters compared to other treatments. Two clusters showed particularly unusual responses to 23C: the development of one winter barley cluster was extremely accelerated by the 23C treatment, whereas the development of one spring barley cluster was significantly delayed. Ambient temperature assumes importance as a regulatory cue in the intricate and complex temporal and spatial regulation network of plant development in cereals and acts mostly through its regulatory effect on certain developmental phases such as the onset and duration of the intensive stem elongation

Las trampas de la escalada simétrica en la terapia familiar. Una familia de psicólogos.

La terapeuta relata el caso de una familia que la consulta por los problemas de su hijo mayor violento y que no asume sus responsabilidades frente a su mujer y a su hijo. El hecho de que se trate de una familia toda de psicólogos amplifica el problema de la simetría y permite comprender mejor que ésta puede ser una trampa muy peligrosa para el terapeuta

Estudio de viabilidad acerca de la instalación de un sistema de bikesharing en la ciudad de Mar del Plata

La forma en que los individuos se desplazan en las ciudades ha ido cambiando desde finales del siglo XX. El surgimiento de un nuevo paradigma de movilidad, asociado a los conceptos de sustentabilidad y sostenibilidad, alentó la utilización de la bicicleta como medio de transporte. El objetivo de la presente investigación es analizar la viabilidad acerca de la instalación de un sistema de bicicletas compartidas en la ciudad de Mar del Plata, Argentina. A tal efecto se concretaron una serie de encuentros con encargados del diseño y la elaboración de políticas públicas y, además, se realizó una encuesta para conocer la opinión de los potenciales usuarios de un esquema de movilidad con las características mencionadas. Los resultados indican que la ciudad dispone con las aptitudes necesarias para proyectar la instalación de una red de bikesharing local. Se presentan las valoraciones y la disposición para utilizarlo por parte de residentes y turistas y la opinión de los funcionarios públicos relacionada con la dinámica de transporte urbano. El trabajo constituye un análisis de tipo exploratorio y da cuenta de algunas recomendaciones que deberían ser consideradas para el funcionamiento exitoso del proyecto. En particular, se sugiere en una primera etapa, un diseño de la red con forma de anillos concéntricos partiendo de la zona céntrica que podría ser extendida, en el mediano plazo, y una vez consolidado el sistema, hacia las áreas más alejadas de la ciudad. De tal forma, en sus comienzos, posiblemente fuera utilizado para fines recreativos y, paulatinamente, se extendiera para favorecer desplazamientos desde y hacia establecimientos educativos y lugares de trabajo.Fil: Bullrich, Ignacio Tomás. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina

Las trampas de la escalada simétrica en la terapia familiar. Una familia de psicólogos.

La terapeuta relata el caso de una familia que la consulta por los problemas de su hijo mayor violento y que no asume sus responsabilidades frente a su mujer y a su hijo. El hecho de que se trate de una familia toda de psicólogos amplifica el problema de la simetría y permite comprender mejor que ésta puede ser una trampa muy peligrosa para el terapeuta

La educación en la constitución alemana de 11 de agosto de 1919

Una gran renovación espiritual, material y moral ha seguido a la guerra: la educación, factor fundamental en la formación del individuo y en la organización de la sociedad no podía quedar ajena a ello. El movimiento de reforma de la enseñanza que había comenzado mucho antes de que estallase la guerra, recrudeció durante ésta, quizás por las mismas fallas que se revelaron en la preparación de los ciudadanos de los países beligerantes, fallas que se atribuyeron a deficiencias de los sistemas de enseñanza. Por eso una de las primeras preocupaciones de la post guerra ha sido la reforma y el mejoramiento de esos sistemas.Facultad de Humanidades y Ciencias de la Educació