WorldWideScience

Sample records for terrestris achieve high

  1. Winter active bumblebees (Bombus terrestris achieve high foraging rates in urban Britain.

    Directory of Open Access Journals (Sweden)

    Ralph J Stelzer

    2010-03-01

    Full Text Available Foraging bumblebees are normally associated with spring and summer in northern Europe. However, there have been sightings of the bumblebee Bombus terrestris during the warmer winters in recent years in southern England. But what floral resources are they relying upon during winter and how much winter forage can they collect?To test if urban areas in the UK provide a rich foraging niche for bees we set up colonies of B. terrestris in the field during two late winter periods (2005/6 & 2006/7 in London, UK, and measured their foraging performance. Fully automatic radio-frequency identification (RFID technology was used in 2006/7 to enable us to record the complete foraging activity of individually tagged bees. The number of bumblebees present during winter (October 2007 to March 2008 and the main plants they visited were also recorded during transect walks. Queens and workers were observed throughout the winter, suggesting a second generation of bee colonies active during the winter months. Mass flowering shrubs such as Mahonia spp. were identified as important food resources. The foraging experiments showed that bees active during the winter can attain nectar and pollen foraging rates that match, and even surpass, those recorded during summer.B. terrestris in the UK are now able to utilise a rich winter foraging resource in urban parks and gardens that might at present still be under-exploited, opening up the possibility of further changes in pollinator phenology.

  2. Winter active bumblebees (Bombus terrestris) achieve high foraging rates in urban Britain.

    Science.gov (United States)

    Stelzer, Ralph J; Chittka, Lars; Carlton, Marc; Ings, Thomas C

    2010-03-05

    Foraging bumblebees are normally associated with spring and summer in northern Europe. However, there have been sightings of the bumblebee Bombus terrestris during the warmer winters in recent years in southern England. But what floral resources are they relying upon during winter and how much winter forage can they collect? To test if urban areas in the UK provide a rich foraging niche for bees we set up colonies of B. terrestris in the field during two late winter periods (2005/6 & 2006/7) in London, UK, and measured their foraging performance. Fully automatic radio-frequency identification (RFID) technology was used in 2006/7 to enable us to record the complete foraging activity of individually tagged bees. The number of bumblebees present during winter (October 2007 to March 2008) and the main plants they visited were also recorded during transect walks. Queens and workers were observed throughout the winter, suggesting a second generation of bee colonies active during the winter months. Mass flowering shrubs such as Mahonia spp. were identified as important food resources. The foraging experiments showed that bees active during the winter can attain nectar and pollen foraging rates that match, and even surpass, those recorded during summer. B. terrestris in the UK are now able to utilise a rich winter foraging resource in urban parks and gardens that might at present still be under-exploited, opening up the possibility of further changes in pollinator phenology.

  3. High efficiency, long life terrestrial solar panel

    Science.gov (United States)

    Chao, T.; Khemthong, S.; Ling, R.; Olah, S.

    1977-01-01

    The design of a high efficiency, long life terrestrial module was completed. It utilized 256 rectangular, high efficiency solar cells to achieve high packing density and electrical output. Tooling for the fabrication of solar cells was in house and evaluation of the cell performance was begun. Based on the power output analysis, the goal of a 13% efficiency module was achievable.

  4. Poor Results for High Achievers

    Science.gov (United States)

    Bui, Sa; Imberman, Scott; Craig, Steven

    2012-01-01

    Three million students in the United States are classified as gifted, yet little is known about the effectiveness of traditional gifted and talented (G&T) programs. In theory, G&T programs might help high-achieving students because they group them with other high achievers and typically offer specially trained teachers and a more advanced…

  5. High Efficiency, High Density Terrestrial Panel. [for solar cell modules

    Science.gov (United States)

    Wohlgemuth, J.; Wihl, M.; Rosenfield, T.

    1979-01-01

    Terrestrial panels were fabricated using rectangular cells. Packing densities in excess of 90% with panel conversion efficiencies greater than 13% were obtained. Higher density panels can be produced on a cost competitive basis with the standard salami panels.

  6. High Intensity Laser Power Beaming Architecture for Space and Terrestrial Missions

    Science.gov (United States)

    Nayfeh, Taysir; Fast, Brian; Raible, Daniel; Dinca, Dragos; Tollis, Nick; Jalics, Andrew

    2011-01-01

    High Intensity Laser Power Beaming (HILPB) has been developed as a technique to achieve Wireless Power Transmission (WPT) for both space and terrestrial applications. In this paper, the system architecture and hardware results for a terrestrial application of HILPB are presented. These results demonstrate continuous conversion of high intensity optical energy at near-IR wavelengths directly to electrical energy at output power levels as high as 6.24 W from the single cell 0.8 cm2 aperture receiver. These results are scalable, and may be realized by implementing receiver arraying and utilizing higher power source lasers. This type of system would enable long range optical refueling of electric platforms, such as MUAV s, airships, robotic exploration missions and provide power to spacecraft platforms which may utilize it to drive electric means of propulsion.

  7. Catholic High Schools and Rural Academic Achievement.

    Science.gov (United States)

    Sander, William

    1997-01-01

    A study of national longitudinal data examined effects of rural Catholic high schools on mathematics achievement, high school graduation rates, and the likelihood that high school graduates attend college. Findings indicate that rural Catholic high schools had a positive effect on mathematics test scores and no effect on graduation rates or rates…

  8. High academic achievement in psychotic students.

    Science.gov (United States)

    Defries, Z; Grothe, L

    1978-02-01

    The authors studied 21 schizophrenic and borderline college students who achieved B+ or higher grade averages and underwent psychotherapy while in college. High academic achievement was found to provide relief from feelings of worthlessness and ineffectuality resulting from poor relationships with parents, siblings, and peers. Psychotherapy and the permissive yet supportive college atmosphere reinforced the students' self-esteem.

  9. Student Perceptions of High-Achieving Classmates

    Science.gov (United States)

    Händel, Marion; Vialle, Wilma; Ziegler, Albert

    2013-01-01

    The reported study investigated students' perceptions of their high-performing classmates in terms of intelligence, social skills, and conscientiousness in different school subjects. The school subjects for study were examined with regard to cognitive, physical, and gender-specific issues. The results show that high academic achievements in…

  10. Terrestrial Planet Finder Coronagraph High Accuracy Optical Propagation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The Terrestrial Planet Finder (TPF) project is considering several approaches to discovering planets orbiting stars far from earth and assessing their suitability to...

  11. Low and high achievers in math

    DEFF Research Database (Denmark)

    Overgaard, Steffen; Tonnesen, Pia Beck; Weng, Peter

    2016-01-01

    In this session we will present the results of the preliminary analysis of the qualitative and quantitative data, which can be used to enhance the teaching of low and high mathematics achievers so as to increase their mathematical knowledge and confidence....

  12. Ion escape fluxes from the terrestrial high-latitude ionosphere

    International Nuclear Information System (INIS)

    Barakat, A.R.; Schunk, R.W.; Moore, T.E.; Waite, J.H. Jr.

    1987-01-01

    The coupled continuity and momentum equations for H + , O + , and electrons were solved for the terrestrial ionosphere in order to determine the limiting ion escape fluxes at high latitudes. The effects of solar cycle, season, geomagnetic activity, and the altitude of the acceleration region on the ion escape fluxes were studied for average conditions. In addition, a systematic parameter study was conducted to determine the extent to which variations in ionospheric conditions (for example, electron temperature, ion temperature, induced vertical ion drifts, etc.) can affect the results. The main conclusions of the study are as follows: (1) as solar activity increases, the general trend is for an increase in the limiting O + escape flux and a decrease in the limiting H + escape flux; (2) in winter the limiting escape fluxes of both O + and H + are larger than those in summer, particularly for low geomagnetic activity; (3) the O + content of the ion outflow increases with increasing ''demand'' imposed on the ionosphere by a high-altitude acceleration process, with increasing solar activity, with increasing geomagnetic activity, with increasing solar elevation from winter to summer, and with a lowering of the altitude of the acceleration region; (4) when H + is in a near-diffusive equilibrium state and a selective mechanism accelerates O + , the limiting O + escape flux is significantly reduced compared to that obtained when an H + outflow also occurs; and (5) at a given time or location the general trends described above can be significantly modified or even reversed owing to natural variations of the ionospheric ion and electron temperatures, induced vertical ion drifts, etc. The general trends obtained for average conditions appear to mimic the qualitative behavior determined from statistically averaged data for comparable absolute escape flux magnitudes

  13. Early predictors of high school mathematics achievement.

    Science.gov (United States)

    Siegler, Robert S; Duncan, Greg J; Davis-Kean, Pamela E; Duckworth, Kathryn; Claessens, Amy; Engel, Mimi; Susperreguy, Maria Ines; Chen, Meichu

    2012-07-01

    Identifying the types of mathematics content knowledge that are most predictive of students' long-term learning is essential for improving both theories of mathematical development and mathematics education. To identify these types of knowledge, we examined long-term predictors of high school students' knowledge of algebra and overall mathematics achievement. Analyses of large, nationally representative, longitudinal data sets from the United States and the United Kingdom revealed that elementary school students' knowledge of fractions and of division uniquely predicts those students' knowledge of algebra and overall mathematics achievement in high school, 5 or 6 years later, even after statistically controlling for other types of mathematical knowledge, general intellectual ability, working memory, and family income and education. Implications of these findings for understanding and improving mathematics learning are discussed.

  14. A meteorological distribution system for high-resolution terrestrial modeling (MicroMet)

    Science.gov (United States)

    Glen E. Liston; Kelly Elder

    2006-01-01

    An intermediate-complexity, quasi-physically based, meteorological model (MicroMet) has been developed to produce high-resolution (e.g., 30-m to 1-km horizontal grid increment) atmospheric forcings required to run spatially distributed terrestrial models over a wide variety of landscapes. The following eight variables, required to run most terrestrial models, are...

  15. A theory of ionospheric dynamo for complete model of terrestrial space at high and medium latitudes

    International Nuclear Information System (INIS)

    Vardanyan, Yu.S.

    1992-01-01

    A multi-layer model of terrestrial cosmic space at high and medium latitudes is considered in the approximation of infinite conductivity of the Earth taking into account the ambipolar diffusion processes in upper layers of ionosphere. 14 refs

  16. Achieving high data throughput in research networks

    International Nuclear Information System (INIS)

    Matthews, W.; Cottrell, L.

    2001-01-01

    After less than a year of operation, the BaBar experiment at SLAC has collected almost 100 million particle collision events in a database approaching 165TB. Around 20 TB of data has been exported via the Internet to the BaBar regional center at IN2P3 in Lyon, France, and around 40TB of simulated data has been imported from the Lawrence Livermore National Laboratory (LLNL). BaBar collaborators plan to double data collection each year and export a third of the data to IN2P3. So within a few years the SLAC OC3 (155 Mbps) connection will be fully utilized by file transfer to France alone. Upgrades to infrastructure is essential and detailed understanding of performance issues and the requirements for reliable high throughput transfers is critical. In this talk results from active and passive monitoring and direct measurements of throughput will be reviewed. Methods for achieving the ambitious requirements will be discussed

  17. Achieving High Data Throughput in Research Networks

    International Nuclear Information System (INIS)

    Matthews, W

    2004-01-01

    After less than a year of operation, the BaBar experiment at SLAC has collected almost 100 million particle collision events in a database approaching 165TB. Around 20 TB of data has been exported via the Internet to the BaBar regional center at IN2P3 in Lyon, France, and around 40TB of simulated data has been imported from the Lawrence Livermore National Laboratory (LLNL). BaBar collaborators plan to double data collection each year and export a third of the data to IN2P3. So within a few years the SLAC OC3 (155Mbps) connection will be fully utilized by file transfer to France alone. Upgrades to infrastructure is essential and detailed understanding of performance issues and the requirements for reliable high throughput transfers is critical. In this talk results from active and passive monitoring and direct measurements of throughput will be reviewed. Methods for achieving the ambitious requirements will be discussed

  18. Attitudes and Opinions from the Nation's High Achieving Teens: 26th Annual Survey of High Achievers.

    Science.gov (United States)

    Who's Who among American High School Students, Lake Forest, IL.

    A national survey of 3,351 high achieving high school students (junior and senior level) was conducted. All students had A or B averages. Topics covered include lifestyles, political beliefs, violence and entertainment, education, cheating, school violence, sexual violence and date rape, peer pressure, popularity, suicide, drugs and alcohol,…

  19. High Involvement Mothers of High Achieving Children: Potential Theoretical Explanations

    Science.gov (United States)

    Hunsaker, Scott L.

    2013-01-01

    In American society, parents who have high aspirations for the achievements of their children are often viewed by others in a negative light. Various pejoratives such as "pushy parent," "helicopter parent," "stage mother," and "soccer mom" are used in the common vernacular to describe these parents. Multiple…

  20. Human nutrition in cold and high terrestrial altitudes

    Science.gov (United States)

    Srivastava, K. K.; Kumar, Ratan

    1992-03-01

    The calorie and nutritional requirements for a man working in an alien hostile environment of cold regions and high altitude are described and compared to those of normal requirements. Carbohydrates, fats and vitamins fulfilling the caloric and nutritional requirements are generally available in adequate amounts except under conditions of appetite loss. However, the proteins and amino acids should be provided in such a way as to meet the altered behavioral and metabolic requirements. Work in extreme cold requires fulfilling enhanced calorie needs. In high mountainous regions, cold combined with hypoxia produced loss of appetite and necessitated designing of special foods.

  1. Achieving strategic surety for high consequence software

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, G.M.

    1996-09-01

    A strategic surety roadmap for high consequence software systems under the High Integrity Software (HIS) Program at Sandia National Laboratories guides research in identifying methodologies to improve software surety. Selected research tracks within this roadmap are identified and described detailing current technology and outlining advancements to be pursued over the coming decade to reach HIS goals. The tracks discussed herein focus on Correctness by Design, and System Immunology{trademark}. Specific projects are discussed with greater detail given on projects involving Correct Specification via Visualization, Synthesis, & Analysis; Visualization of Abstract Objects; and Correct Implementation of Components.

  2. Early Predictors of High School Mathematics Achievement

    Science.gov (United States)

    Siegler, Robert S.; Duncan, Greg J.; Davis-Kean, Pamela E.; Duckworth, Kathryn; Claessens, Amy; Engel, Mimi; Susperreguy, Maria Ines; Meichu, Chen

    2012-01-01

    Identifying the types of mathematics content knowledge that are most predictive of students' long-term learning is essential for improving both theories of mathematical development and mathematics education. To identify these types of knowledge, we examined long-term predictors of high school students' knowledge of algebra and overall mathematics…

  3. Self-Concept and Achievement Motivation of High School Students

    Science.gov (United States)

    Lawrence, A. S. Arul; Vimala, A.

    2013-01-01

    The present study "Self-concept and Achievement Motivation of High School Students" was investigated to find the relationship between Self-concept and Achievement Motivation of High School Students. Data for the study were collected using Self-concept Questionnaire developed by Raj Kumar Saraswath (1984) and Achievement Motive Test (ACMT)…

  4. Perspectives of High-Achieving Women on Teaching

    Science.gov (United States)

    Snodgrass, Helen

    2010-01-01

    High-achieving women are significantly less likely to enter the teaching profession than they were just 40 years ago. Why? While the social and economic reasons for this decline have been well documented in the literature, what is lacking is a discussion with high-achieving women, as they make their first career decisions, about their perceptions…

  5. What factors determine academic achievement in high achieving undergraduate medical students? A qualitative study.

    Science.gov (United States)

    Abdulghani, Hamza M; Al-Drees, Abdulmajeed A; Khalil, Mahmood S; Ahmad, Farah; Ponnamperuma, Gominda G; Amin, Zubair

    2014-04-01

    Medical students' academic achievement is affected by many factors such as motivational beliefs and emotions. Although students with high intellectual capacity are selected to study medicine, their academic performance varies widely. The aim of this study is to explore the high achieving students' perceptions of factors contributing to academic achievement. Focus group discussions (FGD) were carried out with 10 male and 9 female high achieving (scores more than 85% in all tests) students, from the second, third, fourth and fifth academic years. During the FGDs, the students were encouraged to reflect on their learning strategies and activities. The discussion was audio-recorded, transcribed and analysed qualitatively. Factors influencing high academic achievement include: attendance to lectures, early revision, prioritization of learning needs, deep learning, learning in small groups, mind mapping, learning in skills lab, learning with patients, learning from mistakes, time management, and family support. Internal motivation and expected examination results are important drivers of high academic performance. Management of non-academic issues like sleep deprivation, homesickness, language barriers, and stress is also important for academic success. Addressing these factors, which might be unique for a given student community, in a systematic manner would be helpful to improve students' performance.

  6. A Meteorological Distribution System for High Resolution Terrestrial Modeling (MicroMet)

    Science.gov (United States)

    Liston, G. E.; Elder, K.

    2004-12-01

    Spatially distributed terrestrial models generally require atmospheric forcing data on horizontal grids that are of higher resolution than available meteorological data. Furthermore, the meteorological data collected may not necessarily represent the area of interest's meteorological variability. To address these deficiencies, computationally efficient and physically realistic methods must be developed to take available meteorological data sets (e.g., meteorological tower observations) and generate high-resolution atmospheric-forcing distributions. This poster describes MicroMet, a quasi-physically-based, but simple meteorological distribution model designed to produce high-resolution (e.g., 5-m to 1-km horizontal grid increments) meteorological data distributions required to run spatially distributed terrestrial models over a wide variety of landscapes. The model produces distributions of the seven fundamental atmospheric forcing variables required to run most terrestrial models: air temperature, relative humidity, wind speed, wind direction, incoming solar radiation, incoming longwave radiation, and precipitation. MicroMet includes a preprocessor that analyzes meteorological station data and identifies and repairs potential data deficiencies. The model uses known relationships between meteorological variables and the surrounding area (primarily topography) to distribute those variables over any given landscape. MicroMet performs two kinds of adjustments to available meteorological data: 1) when there are data at more than one location, at a given time, the data are spatially interpolated over the domain using a Barnes objective analysis scheme, and 2) physical sub-models are applied to each MicroMet variable to improve its realism at a given point in space and time with respect to the terrain. The three, 25-km by 25-km, Cold Land Processes Experiment (CLPX) mesoscale study areas (MSAs: Fraser, North Park, and Rabbit Ears) will be used as example Micro

  7. High resolution measurement of light in terrestrial ecosystems using photodegrading dyes.

    Directory of Open Access Journals (Sweden)

    Javier Roales

    Full Text Available Incoming solar radiation is the main determinant of terrestrial ecosystem processes, such as primary production, litter decomposition, or soil mineralization rates. Light in terrestrial ecosystems is spatially and temporally heterogeneous due to the interaction among sunlight angle, cloud cover and tree-canopy structure. To integrate this variability and to know light distribution over time and space, a high number of measurements are needed, but tools to do this are usually expensive and limited. An easy-to-use and inexpensive method that can be used to measure light over time and space is needed. We used two photodegrading fluorescent organic dyes, rhodamine WT (RWT and fluorescein, for the quantification of light. We measured dye photodegradation as the decrease in fluorescence across an irradiance gradient from full sunlight to deep shade. Then, we correlated it to accumulated light measured with PAR quantum sensors and obtained a model for this behavior. Rhodamine WT and fluorescein photodegradation followed an exponential decay curve with respect to accumulated light. Rhodamine WT degraded slower than fluorescein and remained unaltered after exposure to temperature changes. Under controlled conditions, fluorescence of both dyes decreased when temperatures increased, but returned to its initial values after cooling to the pre-heating temperature, indicating no degradation. RWT and fluorescein can be used to measure light under a varying range of light conditions in terrestrial ecosystems. This method is particularly useful to integrate solar radiation over time and to measure light simultaneously at different locations, and might be a better alternative to the expensive and time consuming traditional light measurement methods. The accuracy, low price and ease of this method make it a powerful tool for intensive sampling of large areas and for developing high resolution maps of light in an ecosystem.

  8. Highly Accurate Tree Models Derived from Terrestrial Laser Scan Data: A Method Description

    Directory of Open Access Journals (Sweden)

    Jan Hackenberg

    2014-05-01

    Full Text Available This paper presents a method for fitting cylinders into a point cloud, derived from a terrestrial laser-scanned tree. Utilizing high scan quality data as the input, the resulting models describe the branching structure of the tree, capable of detecting branches with a diameter smaller than a centimeter. The cylinders are stored as a hierarchical tree-like data structure encapsulating parent-child neighbor relations and incorporating the tree’s direction of growth. This structure enables the efficient extraction of tree components, such as the stem or a single branch. The method was validated both by applying a comparison of the resulting cylinder models with ground truth data and by an analysis between the input point clouds and the models. Tree models were accomplished representing more than 99% of the input point cloud, with an average distance from the cylinder model to the point cloud within sub-millimeter accuracy. After validation, the method was applied to build two allometric models based on 24 tree point clouds as an example of the application. Computation terminated successfully within less than 30 min. For the model predicting the total above ground volume, the coefficient of determination was 0.965, showing the high potential of terrestrial laser-scanning for forest inventories.

  9. Achievement goals and perfectionism of high school students

    Directory of Open Access Journals (Sweden)

    Milojević Milica

    2009-01-01

    Full Text Available This research has been investigating one of the most contemporary approaches of achievement motivation - Achievement Goal Theory, which uses the construct of achievement goals. The construct of achievement goals involves three types of achievement goals: mastery goals, performance approach goals and performance avoidance goals. The main goal of the research was to examine correlation between perfectionism and its aspects with particular types of achievement goals. Also, the goal was to investigate the difference concerning gender regarding the achievement goals. The sample consisted of 200 senior year high school participants. The following instruments were used: Multi-dimensional scale of perfectionism (MSP and Test of achievement goals (TCP. The research results indicate that there is significant positive correlation between: perfectionism with performance approach goals and performance avoidance goals, concern over mistakes and parental expectations with performance approach goals and performance avoidance goals, personal standards and organization with mastery goals and performance approach goals, parental criticism and doubts about action with performance avoidance goals. Significant negative correlation was found between parental criticism and mastery goals. The results concerning the second goal indicates the female subjects have higher average scores in mastery goals.

  10. Student Perception of Academic Achievement Factors at High School

    OpenAIRE

    Bahar, Mustafa

    2015-01-01

    Measuring the quality of the ‘product’ is elemental in education, and most studies depend on observational data about student achievement factors, focusing overwhelmingly on quantitative data namely achievement scores, school data like attendance, facilities, expenditure class size etc. But there is little evidence of learner perceptions. 553 students from two different universities, who graduated from 3 high school types, were asked to respond to two fundamental questions to reflect on schoo...

  11. Exploring High-Achieving Students' Images of Mathematicians

    Science.gov (United States)

    Aguilar, Mario Sánchez; Rosas, Alejandro; Zavaleta, Juan Gabriel Molina; Romo-Vázquez, Avenilde

    2016-01-01

    The aim of this study is to describe the images that a group of high-achieving Mexican students hold of mathematicians. For this investigation, we used a research method based on the Draw-A-Scientist Test (DAST) with a sample of 63 Mexican high school students. The group of students' pictorial and written descriptions of mathematicians assisted us…

  12. Academic Self-Efficacy of High Achieving Students in Mexico

    Science.gov (United States)

    Camelo-Lavadores, Ana Karen; Sánchez-Escobedo, Pedro; Pinto-Sosa, Jesus

    2017-01-01

    The purpose of this study was to explore for differences in the academic self-efficacy of Mexican high school students. A gird questionnaire was administered to 1,460 students form private and public schools. As expected, high achieving students showed significantly higher academic self-efficacy that their peers. However, interesting gender…

  13. Performance Evaluation of WiMAX Broadband from High Altitude Platform Cellular System and Terrestrial Coexistence Capability

    Directory of Open Access Journals (Sweden)

    Yang Z

    2008-01-01

    Full Text Available The performance obtained from providing worldwide interoperability for microwave access (WiMAX from high altitude platforms (HAPs with multiple antenna payloads is investigated, and the coexistence capability with multiple-operator terrestrial WiMAX deployments is examined. A scenario composed of a single HAP and coexisting multiple terrestrial WiMAX base stations deployed inside the HAP coverage area (with radius of 30 km to provide services to fixed users with the antenna mounted on the roof with a directive antenna to receive signals from HAPs is proposed. A HAP cellular configuration with different possible reuse patterns is established. The coexistence performance is assessed in terms of HAP downlink and uplink performance, interfered by terrestrial WiMAX deployment. Simulation results show that it is effective to deliver WiMAX via HAPs and share the spectrum with terrestrial systems.

  14. Performance Evaluation of WiMAX Broadband from High Altitude Platform Cellular System and Terrestrial Coexistence Capability

    Directory of Open Access Journals (Sweden)

    T. Hult

    2008-12-01

    Full Text Available The performance obtained from providing worldwide interoperability for microwave access (WiMAX from high altitude platforms (HAPs with multiple antenna payloads is investigated, and the coexistence capability with multiple-operator terrestrial WiMAX deployments is examined. A scenario composed of a single HAP and coexisting multiple terrestrial WiMAX base stations deployed inside the HAP coverage area (with radius of 30 km to provide services to fixed users with the antenna mounted on the roof with a directive antenna to receive signals from HAPs is proposed. A HAP cellular configuration with different possible reuse patterns is established. The coexistence performance is assessed in terms of HAP downlink and uplink performance, interfered by terrestrial WiMAX deployment. Simulation results show that it is effective to deliver WiMAX via HAPs and share the spectrum with terrestrial systems.

  15. a New Approach for Subway Tunnel Deformation Monitoring: High-Resolution Terrestrial Laser Scanning

    Science.gov (United States)

    Li, J.; Wan, Y.; Gao, X.

    2012-07-01

    With the improvement of the accuracy and efficiency of laser scanning technology, high-resolution terrestrial laser scanning (TLS) technology can obtain high precise points-cloud and density distribution and can be applied to high-precision deformation monitoring of subway tunnels and high-speed railway bridges and other fields. In this paper, a new approach using a points-cloud segmentation method based on vectors of neighbor points and surface fitting method based on moving least squares was proposed and applied to subway tunnel deformation monitoring in Tianjin combined with a new high-resolution terrestrial laser scanner (Riegl VZ-400). There were three main procedures. Firstly, a points-cloud consisted of several scanning was registered by linearized iterative least squares approach to improve the accuracy of registration, and several control points were acquired by total stations (TS) and then adjusted. Secondly, the registered points-cloud was resampled and segmented based on vectors of neighbor points to select suitable points. Thirdly, the selected points were used to fit the subway tunnel surface with moving least squares algorithm. Then a series of parallel sections obtained from temporal series of fitting tunnel surfaces were compared to analysis the deformation. Finally, the results of the approach in z direction were compared with the fiber optical displacement sensor approach and the results in x, y directions were compared with TS respectively, and comparison results showed the accuracy errors of x, y, z directions were respectively about 1.5 mm, 2 mm, 1 mm. Therefore the new approach using high-resolution TLS can meet the demand of subway tunnel deformation monitoring.

  16. A NEW APPROACH FOR SUBWAY TUNNEL DEFORMATION MONITORING: HIGH-RESOLUTION TERRESTRIAL LASER SCANNING

    Directory of Open Access Journals (Sweden)

    J. Li

    2012-07-01

    Full Text Available With the improvement of the accuracy and efficiency of laser scanning technology, high-resolution terrestrial laser scanning (TLS technology can obtain high precise points-cloud and density distribution and can be applied to high-precision deformation monitoring of subway tunnels and high-speed railway bridges and other fields. In this paper, a new approach using a points-cloud segmentation method based on vectors of neighbor points and surface fitting method based on moving least squares was proposed and applied to subway tunnel deformation monitoring in Tianjin combined with a new high-resolution terrestrial laser scanner (Riegl VZ-400. There were three main procedures. Firstly, a points-cloud consisted of several scanning was registered by linearized iterative least squares approach to improve the accuracy of registration, and several control points were acquired by total stations (TS and then adjusted. Secondly, the registered points-cloud was resampled and segmented based on vectors of neighbor points to select suitable points. Thirdly, the selected points were used to fit the subway tunnel surface with moving least squares algorithm. Then a series of parallel sections obtained from temporal series of fitting tunnel surfaces were compared to analysis the deformation. Finally, the results of the approach in z direction were compared with the fiber optical displacement sensor approach and the results in x, y directions were compared with TS respectively, and comparison results showed the accuracy errors of x, y, z directions were respectively about 1.5 mm, 2 mm, 1 mm. Therefore the new approach using high-resolution TLS can meet the demand of subway tunnel deformation monitoring.

  17. Beta Diversity in a Highly Heterogeneous Area: Disentangling Species and Taxonomic Dissimilarity for Terrestrial Vertebrates.

    Science.gov (United States)

    Calderón-Patrón, Jaime M; Goyenechea, Irene; Ortiz-Pulido, Raúl; Castillo-Cerón, Jesús; Manriquez, Norma; Ramírez-Bautista, Aurelio; Rojas-Martínez, Alberto E; Sánchez-Rojas, Gerardo; Zuria, Iriana; Moreno, Claudia E

    2016-01-01

    Quantifying differences in species composition among communities provides important information related to the distribution, conservation and management of biodiversity, especially when two components are recognized: dissimilarity due to turnover, and dissimilarity due to richness differences. The ecoregions in central Mexico, within the Mexican Transition Zone, have outstanding environmental heterogeneity and harbor huge biological richness, besides differences in the origin of the biota. Therefore, biodiversity studies in this area require the use of complementary measures to achieve appropriate information that may help in the design of conservation strategies. In this work we analyze the dissimilarity of terrestrial vertebrates, and the components of turnover and richness differences, among six ecoregions in the state of Hidalgo, central Mexico. We follow two approaches: one based on species level dissimilarity, and the second on taxonomic dissimilarity. We used databases from the project "Biodiversity in the state of Hidalgo". Our results indicate that species dissimilarity is higher than taxonomic dissimilarity, and that turnover contributes more than richness differences, both for species and taxonomic total dissimilarity. Moreover, total dissimilarity, turnover dissimilarity and the dissimilarity due to richness differences were positively related in the four vertebrate groups. Reptiles had the highest values of dissimilarity, followed by mammals, amphibians and birds. For reptiles, birds, and mammals, species turnover was the most important component, while richness differences had a higher contribution for amphibians. The highest values of dissimilarity occurred between environmentally contrasting ecoregions (i.e., tropical and temperate forests), which suggests that environmental heterogeneity and differences in the origin of biotas are key factors driving beta diversity of terrestrial vertebrates among ecoregions in this complex area.

  18. Beta Diversity in a Highly Heterogeneous Area: Disentangling Species and Taxonomic Dissimilarity for Terrestrial Vertebrates

    Science.gov (United States)

    Calderón-Patrón, Jaime M.; Goyenechea, Irene; Ortiz-Pulido, Raúl; Castillo-Cerón, Jesús; Manriquez, Norma; Ramírez-Bautista, Aurelio; Rojas-Martínez, Alberto E.; Sánchez-Rojas, Gerardo; Zuria, Iriana

    2016-01-01

    Quantifying differences in species composition among communities provides important information related to the distribution, conservation and management of biodiversity, especially when two components are recognized: dissimilarity due to turnover, and dissimilarity due to richness differences. The ecoregions in central Mexico, within the Mexican Transition Zone, have outstanding environmental heterogeneity and harbor huge biological richness, besides differences in the origin of the biota. Therefore, biodiversity studies in this area require the use of complementary measures to achieve appropriate information that may help in the design of conservation strategies. In this work we analyze the dissimilarity of terrestrial vertebrates, and the components of turnover and richness differences, among six ecoregions in the state of Hidalgo, central Mexico. We follow two approaches: one based on species level dissimilarity, and the second on taxonomic dissimilarity. We used databases from the project “Biodiversity in the state of Hidalgo”. Our results indicate that species dissimilarity is higher than taxonomic dissimilarity, and that turnover contributes more than richness differences, both for species and taxonomic total dissimilarity. Moreover, total dissimilarity, turnover dissimilarity and the dissimilarity due to richness differences were positively related in the four vertebrate groups. Reptiles had the highest values of dissimilarity, followed by mammals, amphibians and birds. For reptiles, birds, and mammals, species turnover was the most important component, while richness differences had a higher contribution for amphibians. The highest values of dissimilarity occurred between environmentally contrasting ecoregions (i.e., tropical and temperate forests), which suggests that environmental heterogeneity and differences in the origin of biotas are key factors driving beta diversity of terrestrial vertebrates among ecoregions in this complex area. PMID:27500934

  19. Best Practices for Achieving High, Rapid Reading Gains

    Science.gov (United States)

    Carbo, Marie

    2008-01-01

    The percentage of students who read at the proficient level on the National Assessment of Educational Progress (NAEP) has not improved, and is appallingly low. In order for students to achieve high reading gains and become life-long readers, reading comprehension and reading enjoyment must be the top two goals. This article presents several…

  20. Self-Esteem and Academic Achievement of High School Students

    Science.gov (United States)

    Moradi Sheykhjan, Tohid; Jabari, Kamran; Rajeswari, K.

    2014-01-01

    The primary purpose of this study was to determine the influence of self-esteem on academic achievement among high school students in Miandoab City of Iran. The methodology of the research is descriptive and correlation that descriptive and inferential statistics were used to analyze the data. Statistical Society includes male and female high…

  1. Academic achievement of junior high school students with sleep disorders

    Directory of Open Access Journals (Sweden)

    Fijri Auliyanti

    2015-03-01

    Full Text Available Background Sleep disorders are prevalent in adolescents and may influence their academic achievement. To date, no study has been done in Indonesia on academic achievement in students with sleep disorders and its related factors. Objective To assess for relationships between academic achievement and related factors, including gender, motivation and learning strategies, IQ level, maternal educational level, socioeconomic status, family structure, after-hours education program, presence of TV/computer in the bedroom, sleep duration during school days, as well as bedtime and wakeup time difference in junior high school students with sleep disorders. Methods This cross-sectional study was performed from January to March 2013. Subjects were students from five junior high schools in Jakarta who fulfilled the criteria for sleep disorders based on the Sleep Disturbance Scale for Children questionnaire. Results There were 111 study subjects. The prevalence of sleep disorders was 39.7%, mostly in difficulties initiating and maintaining sleep (70.2%. Below-average academic achievement was seen in 47.6% of subjects. Factors significantly related to below-average academic achievement were after-hours education program (prevalence ratio 5.6; 95%CI 1.36 to 23.18; P = 0.017, average IQ level (prevalence ratio 3.26; 95%CI 1.38 to 7.71; P = 0.007, and male gender (prevalence ratio 2.68; 95%CI 1.06 to 6.78; P = 0.037. Conclusion Among junior high school students with sleep disorders, factors related to below-average academic achievement are afterhours education program (more than 2 types, the average IQ level, and male gender.

  2. Terrestrial magnetosphere

    International Nuclear Information System (INIS)

    Pande, D.C.; Agarwal, D.C.

    1982-01-01

    This paper presents a review about terrestrial magnetosphere. During the last few years considerable investigation have been carried out about the properties of Solar Wind and its interaction with planetary magnetic fields. It is therefore of high importance to accumulate all the investigations in a comprehensive form. The paper reviews the property of earth's magnetosphere, magnetosheath, magneto pause, polar cusps, bow shook and plasma sheath. (author)

  3. Achieving high aspect ratio wrinkles by modifying material network stress.

    Science.gov (United States)

    Chen, Yu-Cheng; Wang, Yan; McCarthy, Thomas J; Crosby, Alfred J

    2017-06-07

    Wrinkle aspect ratio, or the amplitude divided by the wavelength, is hindered by strain localization transitions when an increasing global compressive stress is applied to synthetic material systems. However, many examples from living organisms show extremely high aspect ratios, such as gut villi and flower petals. We use three experimental approaches to demonstrate that these high aspect ratio structures can be achieved by modifying the network stress in the wrinkle substrate. We modify the wrinkle stress and effectively delay the strain localization transition, such as folding, to larger aspect ratios by using a zero-stress initial wavy substrate, creating a secondary network with post-curing, or using chemical stress relaxation materials. A wrinkle aspect ratio as high as 0.85, almost three times higher than common values of synthetic wrinkles, is achieved, and a quantitative framework is presented to provide understanding the different strategies and predictions for future investigations.

  4. Parent Involvement Practices of High-Achieving Elementary Science Students

    Science.gov (United States)

    Waller, Samara Susan

    This study addressed a prevalence of low achievement in science courses in an urban school district in Georgia. National leaders and educators have identified the improvement of science proficiency as critical to the future of American industry. The purpose of this study was to examine parent involvement in this school district and its contribution to the academic achievement of successful science students. Social capital theory guided this study by suggesting that students achieve best when investments are made into their academic and social development. A collective case study qualitative research design was used to interview 9 parent participants at 2 elementary schools whose children scored in the exceeds category on the Science CRCT. The research questions focused on what these parents did at home to support their children's academic achievement. Data were collected using a semi-structured interview protocol and analyzed through the categorical aggregation of transcribed interviews. Key findings revealed that the parents invested time and resources in 3 practices: communicating high expectations, supporting and developing key skills, and communicating with teachers. These findings contribute to social change at both the local and community level by creating a starting point for teachers, principals, and district leaders to reexamine the value of parent input in the educational process, and by providing data to support the revision of current parent involvement policies. Possibilities for further study building upon the findings of this study may focus on student perceptions of their parents' parenting as it relates to their science achievement.

  5. High school achievement as a predictor for university performance

    Directory of Open Access Journals (Sweden)

    Meshkani Z

    2004-07-01

    Full Text Available Background: The high-school grade point average ( GPA-H and university entrance examination can predict the university achievement and Purpose. To examine the predictive value of GPA-H for GPA-U Methods: In this cross sectional study, the subjects were 240 medical students at basic science phase of their medical education. Data were collected by a questionnaire, consisting of questions measuring factual background variable and 10 Llikert-type questions measuring attitude. The multiple regression analysis was used. Results: The analysis showed that student GPA were a better predictor for educational achievement of medical students than rank on university entrance exam and students with high GPA have not been on probation at all. Also parent's education and occupation influence the students' attitudes toward their medical study. Conclusion: High-school GPA is a predictor for university GPA .This may warrant further investigation into criteria of medical university entrance exam. Keywords: UNIVERSITY ACHIEVEMENT, HIGH-SCHOOL GPA, UNIVERSITY SUCCESS, PREDICTOR

  6. A High-Resolution Terrestrial Modeling System (TMS): A Demonstration in China

    Science.gov (United States)

    Duan, Q.; Dai, Y.; Zheng, X.; Ye, A.; Ji, D.; Chen, Z.

    2013-12-01

    This presentation describes a terrestrial modeling system (TMS) developed at Beijing Normal University. The TMS is designed to be driven by multi-sensor meteorological and land surface observations, including those from satellites and land based observing stations. The purposes of the TMS are (1) to provide a land surface parameterization scheme fully capable of being coupled with the Earth system models; (2) to provide a standalone platform for retrospective historical simulation and for forecasting of future land surface processes at different space and time scales; and (3) to provide a platform for studying human-Earth system interactions and for understanding climate change impacts. This system is built on capabilities among several groups at BNU, including the Common Land Model (CoLM) system, high-resolution atmospheric forcing data sets, high resolution land surface characteristics data sets, data assimilation and uncertainty analysis platforms, ensemble prediction platform, and high-performance computing facilities. This presentation intends to describe the system design and demonstrate the capabilities of TMS with results from a China-wide application.

  7. [Determination by high performance chromatography, steroid saponins in a biologically active food supplements containing the extract of Tribulus terrestris].

    Science.gov (United States)

    Kozlova, O I; Perederiaev, O I; Ramenskaia, G V

    2011-01-01

    Steroidal saponins are bioactive substances of Tribulus terrestris and can be used to assess the quality of raw materials and processed products from them. For this purpose has been developed the method of qualitative and quantitative determination of steroidal saponins by high performance liquid chromatography with spectrophotometric and mass-selective detection and optimal conditions of sample preparation (70% methanol extraction with sonication and heating); also has been studied steroidal saponins composition of Tribulus terrestris (protodioscin, tribulosaponin B, metilprotodiostsin, terrestrozin H, prototribestin, gracillin and others were found).

  8. The Impact of Inclusive STEM High Schools on Student Achievement

    Directory of Open Access Journals (Sweden)

    Jennifer Gnagey

    2016-05-01

    Full Text Available This study is one of the first to estimate the impact of “inclusive“ science, technology, engineering, and mathematics (STEM high schools using student-level data. We use multiple statistical strategies to estimate the effect on student achievement from 2 years of attendance at six such high schools in Ohio. The results indicate that two schools had positive effects on science achievement that appear to come at the expense of achievement in social studies. The other schools had negligible or, often, negative effects across both STEM and, particularly, non-STEM subjects. These results are consistent with studies indicating that inclusive STEM schools typically focus on problem-based, personalized learning rather than science and mathematics content. The analysis also reveals the importance of accounting for students’ prior test scores in science, in addition to math and reading, when estimating models that use only 1 year of prior test score data—something that existing studies fail to do.

  9. Achieving High Reliability with People, Processes, and Technology.

    Science.gov (United States)

    Saunders, Candice L; Brennan, John A

    2017-01-01

    High reliability as a corporate value in healthcare can be achieved by meeting the "Quadruple Aim" of improving population health, reducing per capita costs, enhancing the patient experience, and improving provider wellness. This drive starts with the board of trustees, CEO, and other senior leaders who ingrain high reliability throughout the organization. At WellStar Health System, the board developed an ambitious goal to become a top-decile health system in safety and quality metrics. To achieve this goal, WellStar has embarked on a journey toward high reliability and has committed to Lean management practices consistent with the Institute for Healthcare Improvement's definition of a high-reliability organization (HRO): one that is committed to the prevention of failure, early identification and mitigation of failure, and redesign of processes based on identifiable failures. In the end, a successful HRO can provide safe, effective, patient- and family-centered, timely, efficient, and equitable care through a convergence of people, processes, and technology.

  10. Generating high temperature tolerant transgenic plants: Achievements and challenges.

    Science.gov (United States)

    Grover, Anil; Mittal, Dheeraj; Negi, Manisha; Lavania, Dhruv

    2013-05-01

    Production of plants tolerant to high temperature stress is of immense significance in the light of global warming and climate change. Plant cells respond to high temperature stress by re-programming their genetic machinery for survival and reproduction. High temperature tolerance in transgenic plants has largely been achieved either by over-expressing heat shock protein genes or by altering levels of heat shock factors that regulate expression of heat shock and non-heat shock genes. Apart from heat shock factors, over-expression of other trans-acting factors like DREB2A, bZIP28 and WRKY proteins has proven useful in imparting high temperature tolerance. Besides these, elevating the genetic levels of proteins involved in osmotic adjustment, reactive oxygen species removal, saturation of membrane-associated lipids, photosynthetic reactions, production of polyamines and protein biosynthesis process have yielded positive results in equipping transgenic plants with high temperature tolerance. Cyclic nucleotide gated calcium channel proteins that regulate calcium influxes across the cell membrane have recently been shown to be the key players in induction of high temperature tolerance. The involvement of calmodulins and kinases in activation of heat shock factors has been implicated as an important event in governing high temperature tolerance. Unfilled gaps limiting the production of high temperature tolerant transgenic plants for field level cultivation are discussed. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  11. Achieving High Resolution Timer Events in Virtualized Environment.

    Science.gov (United States)

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs-Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service). Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events.

  12. Mindmapping: Its effects on student achievement in high school biology

    Science.gov (United States)

    Cunningham, Glennis Edge

    The primary goal of schools is to promote the highest degree of learning possible. Yet teachers spend the majority of their time engaged in lecturing while students spend the majority of their time passively present (Cawelti, 1997, Grinder, 1991; Jackson & Davis, 2000; Jenkins, 1996). Helping students develop proficiency in learning, which translates into using that expertise to construct knowledge in subject domains, is a crucial goal of education. Students need exposure to teaching and learning practices that prepare them for both the classroom and their places in the future workforce (Ettinger, 1998; Longley, Goodchild, Maguire, & Rhind, 2001; NRC, 1996; Texley & Wild, 1996). The purpose of this study was to determine if achievement in high school science courses could be enhanced utilizing mindmapping. The subjects were primarily 9th and 10th graders (n = 147) at a suburban South Texas high school. A pretest-posttest control group design was selected to determine the effects of mindmapping on student achievement as measured by a teacher-developed, panel-validated instrument. Follow-up interviews were conducted with the teacher and a purposive sample of students (n = 7) to determine their perceptions of mindmapping and its effects on teaching and learning. Mindmapping is a strategy for visually displaying large amounts of conceptual, hierarchical information in a concise, organized, and accessible format. Mindmaps arrange information similar to that found on the traditional topic outline into colorful spatial displays that offer the user a view of the "forest" as well as the "trees" (Hyerle, 1996; Wandersee, 1990b). An independent samples t-test and a one-way analysis of covariance (ANCOVA) determined no significant difference in achievement between the groups. The experimental group improved in achievement at least as much as the control group. Several factors may have played a role in the lack of statistically significant results. These factors include the

  13. Computer Security: SAHARA - Security As High As Reasonably Achievable

    CERN Multimedia

    Stefan Lueders, Computer Security Team

    2015-01-01

    History has shown us time and again that our computer systems, computing services and control systems have digital security deficiencies. Too often we deploy stop-gap solutions and improvised hacks, or we just accept that it is too late to change things.    In my opinion, this blatantly contradicts the professionalism we show in our daily work. Other priorities and time pressure force us to ignore security or to consider it too late to do anything… but we can do better. Just look at how “safety” is dealt with at CERN! “ALARA” (As Low As Reasonably Achievable) is the objective set by the CERN HSE group when considering our individual radiological exposure. Following this paradigm, and shifting it from CERN safety to CERN computer security, would give us “SAHARA”: “Security As High As Reasonably Achievable”. In other words, all possible computer security measures must be applied, so long as ...

  14. Relationships Between Achievement Emotions, Motivation and Language Learning Strategies of High, Mid and Low English Language Achievers

    Institute of Scientific and Technical Information of China (English)

    TAN; Jun-ming

    2017-01-01

    Overseas research has shown that achievement emotions have direct relationships with "achievement outcome" and"achievement activities". The purpose of the present study aimed to compare the relationships betweenachievement emotions, motivation, and language learning strategies of high, mid and low achievers in Englishlanguage learning at an international university in a southern province in China. Quantitative data were collectedthrough a questionnaire survey of 74 (16 males, 58 females) TESL major students. Results indicated that studentsin general experienced more positive than negative achievement emotions; more intrinsically rather thanextrinsically motivated to learn English; and quite frequently used a variety of learning strategies to overcome theirlearning difficulties. However, Year Four low-achievers experienced more negative achievement emotions. Theyseldom used metacognitive, affective and social learning strategies, and they had lower degrees of intrinsicmotivation. Implications for institutional support for at risk students are discussed.

  15. A Study of Impulsivity in Low-Achieving and High-Achieving Boys from Lower Income Homes. Final Report.

    Science.gov (United States)

    Cohen, Shirley

    The purpose of this study was to explore the concept of impulsivity as a stylistic dimension affecting cognitive behavior, and whether impulsivity operates as a comprehensive, inflexible orientation in low achievers more than in high achievers. The Matching Familiar Figures Test, the Porteus Maze Test, and the Stroop Color-Word Test were used to…

  16. Downlink Coexistence Performance Assessment and Techniques for WiMAX Services from High Altitude Platform and Terrestrial Deployments

    Directory of Open Access Journals (Sweden)

    Grace D

    2008-01-01

    Full Text Available Abstract We investigate the performance and coexistence techniques for worldwide interoperability for microwave access (WiMAX delivered from high altitude platforms (HAPs and terrestrial systems in shared 3.5 GHz frequency bands. The paper shows that it is possible to provide WiMAX services from individual HAP systems. The coexistence performance is evaluated by appropriate choice of parameters, which include the HAP deployment spacing radius, directive antenna beamwidths based on adopted antenna models for HAPs and receivers. Illustrations and comparisons of coexistence techniques, for example, varying the antenna pointing offset, transmitting and receiving antenna beamwidth, demonstrate efficient ways to enhance the HAP system performance while effectively coexisting with terrestrial WiMAX systems.

  17. Downlink Coexistence Performance Assessment and Techniques for WiMAX Services from High Altitude Platform and Terrestrial Deployments

    Directory of Open Access Journals (Sweden)

    D. Grace

    2008-11-01

    Full Text Available We investigate the performance and coexistence techniques for worldwide interoperability for microwave access (WiMAX delivered from high altitude platforms (HAPs and terrestrial systems in shared 3.5 GHz frequency bands. The paper shows that it is possible to provide WiMAX services from individual HAP systems. The coexistence performance is evaluated by appropriate choice of parameters, which include the HAP deployment spacing radius, directive antenna beamwidths based on adopted antenna models for HAPs and receivers. Illustrations and comparisons of coexistence techniques, for example, varying the antenna pointing offset, transmitting and receiving antenna beamwidth, demonstrate efficient ways to enhance the HAP system performance while effectively coexisting with terrestrial WiMAX systems.

  18. Academic attainment and the high school science experiences among high-achieving African American males

    Science.gov (United States)

    Trice, Rodney Nathaniel

    This study examines the educational experiences of high achieving African American males. More specifically, it analyzes the influences on their successful navigation through high school science. Through a series of interviews, observations, questionnaires, science portfolios, and review of existing data the researcher attempted to obtain a deeper understanding of high achieving African American males and their limitations to academic attainment and high school science experiences. The investigation is limited to ten high achieving African American male science students at Woodcrest High School. Woodcrest is situated at the cross section of a suburban and rural community located in the southeastern section of the United States. Although this investigation involves African American males, all of whom are successful in school, its findings should not be generalized to this nor any other group of students. The research question that guided this study is: What are the limitations to academic attainment and the high school science experiences of high achieving African American males? The student participants expose how suspension and expulsion, special education placement, academic tracking, science instruction, and teacher expectation influence academic achievement. The role parents play, student self-concept, peer relationships, and student learning styles are also analyzed. The anthology of data rendered three overarching themes: (1) unequal access to education, (2) maintenance of unfair educational structures, and (3) authentic characterizations of African American males. Often the policies and practices set in place by school officials aid in creating hurdles to academic achievement. These policies and practices are often formed without meaningful consideration of the unintended consequences that may affect different student populations, particularly the most vulnerable. The findings from this study expose that high achieving African American males face major

  19. Componential Analysis of Analogical-Reasoning Performance of High and Low Achievers.

    Science.gov (United States)

    Armour-Thomas, Eleanor; Allen, Brenda A.

    1990-01-01

    Assessed analogical reasoning in high- and low-achieving students at the high school level and determined whether analogical reasoning was related to academic achievement in ninth grade students (N=54). Results indicated that high achievers performed better than low achievers on all types of analogical-reasoning processes. (Author/ABL)

  20. Parenting Style, Perfectionism, and Creativity in High-Ability and High-Achieving Young Adults

    Science.gov (United States)

    Miller, Angie L.; Lambert, Amber D.; Speirs Neumeister, Kristie L.

    2012-01-01

    The current study explores the potential relationships among perceived parenting style, perfectionism, and creativity in a high-ability and high-achieving young adult population. Using data from 323 honors college students at a Midwestern university, bivariate correlations suggested positive relationships between (a) permissive parenting style and…

  1. Success Despite Socioeconomics: A Case Study of a High-Achieving, High-Poverty School

    Science.gov (United States)

    Tilley, Thomas Brent; Smith, Samuel J.; Claxton, Russell L.

    2012-01-01

    This case study of a high-achieving, high-poverty school describes the school's leadership, culture, and programs that contributed to its success. Data were collected from two surveys (the School Culture Survey and the Vanderbilt Assessment of Leadership in Education), observations at the school site, and interviews with school personnel. The…

  2. High-precision 41K/39K measurements by MC-ICP-MS indicate terrestrial variability of δ41K

    Science.gov (United States)

    Morgan, Leah; Santiago Ramos, Danielle P.; Davidheiser-Kroll, Brett; Faithfull, John; Lloyd, Nicholas S.; Ellam, Rob M.; Higgins, John A.

    2018-01-01

    Potassium is a major component in continental crust, the fourth-most abundant cation in seawater, and a key element in biological processes. Until recently, difficulties with existing analytical techniques hindered our ability to identify natural isotopic variability of potassium isotopes in terrestrial materials. However, measurement precision has greatly improved and a range of K isotopic compositions has now been demonstrated in natural samples. In this study, we present a new technique for high-precision measurement of K isotopic ratios using high-resolution, cold plasma multi-collector mass spectrometry. We apply this technique to demonstrate natural variability in the ratio of 41K to 39K in a diverse group of geological and biological samples, including silicate and evaporite minerals, seawater, and plant and animal tissues. The total range in 41K/39K ratios is ca. 2.6‰, with a long-term external reproducibility of 0.17‰ (2, N=108). Seawater and seawater-derived evaporite minerals are systematically enriched in 41K compared to silicate minerals by ca. 0.6‰, a result consistent with recent findings1, 2. Although our average bulk-silicate Earth value (-0.54‰) is indistinguishable from previously published values, we find systematic δ41K variability in some high-temperature sample suites, particularly those with evidence for the presence of fluids. The δ41K values of biological samples span a range of ca. 1.2‰ between terrestrial mammals, plants, and marine organisms. Implications of terrestrial K isotope variability for the atomic weight of K and K-based geochronology are discussed. Our results indicate that high-precision measurements of stable K isotopes, made using commercially available mass spectrometers, can provide unique insights into the chemistry of potassium in geological and biological systems. 

  3. High spatial variation in terrestrial arthropod species diversity and composition near the Greenland ice cap

    DEFF Research Database (Denmark)

    Hansen, Rikke Reisner; Hansen, Oskar Liset Pryds; Bowden, Joseph James

    2016-01-01

    Arthropods form a major part of the terrestrial species diversity in the Arctic, and are particularly sensitive to temporal changes in the abiotic environment. It is assumed that most Arctic arthropods are habitat generalists and that their diversity patterns exhibit low spatial variation....... The empirical basis for this assumption, however, is weak. We examine the degree of spatial variation in species diversity and assemblage structure among five habitat types at two sites of similar abiotic conditions and plant species composition in southwest Greenland, using standardized field collection...... methods for spiders, beetles and butterflies. We employed non-metric multidimensional scaling, species richness estimation, community dissimilarity and indicator species analysis to test for local (within site)- and regional (between site)-scale differences in arthropod communities. To identify specific...

  4. Achieving sensitive, high-resolution laser spectroscopy at CRIS

    Energy Technology Data Exchange (ETDEWEB)

    Groote, R. P. de [Instituut voor Kern- en Stralingsfysica, KU Leuven (Belgium); Lynch, K. M., E-mail: kara.marie.lynch@cern.ch [EP Department, CERN, ISOLDE (Switzerland); Wilkins, S. G. [The University of Manchester, School of Physics and Astronomy (United Kingdom); Collaboration: the CRIS collaboration

    2017-11-15

    The Collinear Resonance Ionization Spectroscopy (CRIS) experiment, located at the ISOLDE facility, has recently performed high-resolution laser spectroscopy, with linewidths down to 20 MHz. In this article, we present the modifications to the beam line and the newly-installed laser systems that have made sensitive, high-resolution measurements possible. Highlights of recent experimental campaigns are presented.

  5. Dense image matching of terrestrial imagery for deriving high-resolution topographic properties of vegetation locations in alpine terrain

    Science.gov (United States)

    Niederheiser, R.; Rutzinger, M.; Bremer, M.; Wichmann, V.

    2018-04-01

    The investigation of changes in spatial patterns of vegetation and identification of potential micro-refugia requires detailed topographic and terrain information. However, mapping alpine topography at very detailed scales is challenging due to limited accessibility of sites. Close-range sensing by photogrammetric dense matching approaches based on terrestrial images captured with hand-held cameras offers a light-weight and low-cost solution to retrieve high-resolution measurements even in steep terrain and at locations, which are difficult to access. We propose a novel approach for rapid capturing of terrestrial images and a highly automated processing chain for retrieving detailed dense point clouds for topographic modelling. For this study, we modelled 249 plot locations. For the analysis of vegetation distribution and location properties, topographic parameters, such as slope, aspect, and potential solar irradiation were derived by applying a multi-scale approach utilizing voxel grids and spherical neighbourhoods. The result is a micro-topography archive of 249 alpine locations that includes topographic parameters at multiple scales ready for biogeomorphological analysis. Compared with regional elevation models at larger scales and traditional 2D gridding approaches to create elevation models, we employ analyses in a fully 3D environment that yield much more detailed insights into interrelations between topographic parameters, such as potential solar irradiation, surface area, aspect and roughness.

  6. High critical temperature superconductors: Progress achieved after two years

    International Nuclear Information System (INIS)

    Maillard, J.M.; Rammal, R.; Vittorge, M.C.

    1989-01-01

    Progress concerning the theory of high temperature superconductors and activity of laboratories of the CNRS (France) are reviewed and news on strategy, budgets, theoretical research, materials characterization, fabrication process technology transfers, commercialisation, uses and data bases are given [fr

  7. Achieving Mixtures of Ultra-High Performance Concrete

    Directory of Open Access Journals (Sweden)

    Mircea POPA

    2013-07-01

    Full Text Available Ultra-High Performance Concrete (UHPC is a relatively new concrete. According to [11] UHPC is that concrete which features compressive strength over C100/115 class. Up to this point standards for this type of concrete were not adopted, although its characteristic strength exceeds those specified in [33]. Its main property is high compressive strength. This provides the possibility of reducing the section of elements (beams or columns made of this type of concrete, while the load capacity remains high. The study consists in blending mixtures of UHPC made of varying proportions of materials. The authors have obtained strengths of up to 160 MPa. The materials used are: Portland cement, silica fume, quartz powder, steel fibers, superplasticiser, sand and crushed aggregate for concrete - andesite.

  8. Achieving high CRI from warm to super white

    Science.gov (United States)

    Bailey, Edward; Tormey, Ellen S.

    2007-09-01

    Light sources which produce a high color rendering index (CRI) have many applications in the lighting industry today. High color rendering accents the rich color which abounds in nature, interior design, theatrical costumes and props, clothing and fabric, jewelry, and machine vision applications. Multi-wavelength LED sources can pump phosphors at multiple stokes shift emission regimes and when combined with selected direct emission sources can allow for greater flexibility in the production of warm-white and cool white light of specialty interest. Unique solutions to R8 and R14 CRI >95 at 2850K, 4750K, 5250K, and 6750K presented.

  9. CubeSats in Hydrology: Ultra-High Resolution Insights into Vegetation Dynamics and Terrestrial Evaporation

    KAUST Repository

    McCabe, Matthew; Aragon, B.; Houborg, Rasmus; Mascaro, J.

    2017-01-01

    Satellite-based remote sensing has generally necessitated a trade-off between spatial resolution and temporal frequency, affecting the capacity to observe fast hydrological processes and rapidly changing land surface conditions. An avenue for overcoming these spatiotemporal restrictions is the concept of using constellations of satellites, as opposed to the mission focus exemplified by the more conventional space-agency approach to earth observation. Referred to as CubeSats, these platforms offer the potential to provide new insights into a range of earth system variables and processes. Their emergence heralds a paradigm shift from single-sensor launches to an operational approach that envisions tens to hundreds of small, lightweight and comparatively inexpensive satellites placed into a range of low earth orbits. Although current systems are largely limited to sensing in the optical portion of the electromagnetic spectrum, we demonstrate the opportunity and potential that CubeSats present the hydrological community via the retrieval of vegetation dynamics and terrestrial evaporation and foreshadow future sensing capabilities.

  10. CubeSats in Hydrology: Ultra-High Resolution Insights into Vegetation Dynamics and Terrestrial Evaporation

    KAUST Repository

    McCabe, Matthew

    2017-12-01

    Satellite-based remote sensing has generally necessitated a trade-off between spatial resolution and temporal frequency, affecting the capacity to observe fast hydrological processes and rapidly changing land surface conditions. An avenue for overcoming these spatiotemporal restrictions is the concept of using constellations of satellites, as opposed to the mission focus exemplified by the more conventional space-agency approach to earth observation. Referred to as CubeSats, these platforms offer the potential to provide new insights into a range of earth system variables and processes. Their emergence heralds a paradigm shift from single-sensor launches to an operational approach that envisions tens to hundreds of small, lightweight and comparatively inexpensive satellites placed into a range of low earth orbits. Although current systems are largely limited to sensing in the optical portion of the electromagnetic spectrum, we demonstrate the opportunity and potential that CubeSats present the hydrological community via the retrieval of vegetation dynamics and terrestrial evaporation and foreshadow future sensing capabilities.

  11. Vocational Interests of Intellectually Gifted and Highly Achieving Young Adults

    Science.gov (United States)

    Vock, Miriam; Koller, Olaf; Nagy, Gabriel

    2013-01-01

    Background: Vocational interests play a central role in the vocational decision-making process and are decisive for the later job satisfaction and vocational success. Based on Ackerman's (1996) notion of "trait complexes," specific interest profiles of gifted high-school graduates can be expected. Aims: Vocational interests of gifted and…

  12. Learning Disabilities and Achieving High-Quality Education Standards

    Science.gov (United States)

    Gartland, Debi; Strosnider, Roberta

    2017-01-01

    This is an official document of the National Joint Committee on Learning Disabilities (NJCLD), of which Council for Learning Disabilities is a long-standing, active member. With this position paper, NJCLD advocates for the implementation of high-quality education standards (HQES) for students with learning disabilities (LD) and outlines the…

  13. Achievement and New Challenges for High Performance Materials in Europe

    International Nuclear Information System (INIS)

    Fazio, C.; Dubuisson, Ph.

    2013-01-01

    The European approach for nuclear energy sustainability: ESNII. Introduce in the nuclear technology development more sustainability aspects, such as, e.g. • better use of resources; • less waste; • higher system efficiency. All this while keeping very high safety standards

  14. The alien terrestrial invertebrate fauna of the High Arctic archipelago of Svalbard: potential implications for the native flora and fauna

    Directory of Open Access Journals (Sweden)

    Stephen J. Coulson

    2015-09-01

    Full Text Available Experience from the Antarctic indicates that the establishment of alien species may have significant negative effects on native flora and fauna in polar regions and is considered to be amongst the greatest threats to biodiversity. But, there have been few similar studies from the Arctic. Although the terrestrial invertebrate inventory of the Svalbard Archipelago is amongst the most complete for any region of the Arctic, no consideration has yet been made of alien terrestrial invertebrate species, their invasiveness tendencies, threat to the native biology or their route of entry. Such baseline information is critical for appropriate management strategies. Fifteen alien invertebrate species have established in the Svalbard environment, many of which have been introduced via imported soils. Biosecurity legislation now prohibits such activities. None of the recorded established aliens yet show invasive tendencies but some may have locally negative effects. Ten species are considered to be vagrants and a further seven are classified as observations. Vagrants and the observations are not believed to be able to establish in the current tundra environment. The high connectivity of Svalbard has facilitated natural dispersal processes and may explain why few alien species are recorded compared to isolated islands in the maritime Antarctic. The vagrant species observed are conspicuous Lepidoptera, implying that less evident vagrant species are also arriving regularly. Projected climate change may enable vagrant species to establish, with results that are difficult to foresee.

  15. Ultrathin Coaxial Fiber Supercapacitors Achieving High Energy and Power Densities.

    Science.gov (United States)

    Shen, Caiwei; Xie, Yingxi; Sanghadasa, Mohan; Tang, Yong; Lu, Longsheng; Lin, Liwei

    2017-11-15

    Fiber-based supercapacitors have attracted significant interests because of their potential applications in wearable electronics. Although much progress has been made in recent years, the energy and power densities, mechanical strength, and flexibility of such devices are still in need of improvement for practical applications. Here, we demonstrate an ultrathin microcoaxial fiber supercapacitor (μCFSC) with high energy and power densities (2.7 mW h/cm 3 and 13 W/cm 3 ), as well as excellent mechanical properties. The prototype with the smallest reported overall diameter (∼13 μm) is fabricated by successive coating of functional layers onto a single micro-carbon-fiber via a scalable process. Combining the simulation results via the electrochemical model, we attribute the high performance to the well-controlled thin coatings that make full use of the electrode materials and minimize the ion transport path between electrodes. Moreover, the μCFSC features high bending flexibility and large tensile strength (more than 1 GPa), which make it promising as a building block for various flexible energy storage applications.

  16. Achieving High Burnup Targets With Mox Fuels: Techno Economic Implications

    International Nuclear Information System (INIS)

    Clement Ravi Chandar, S.; Sivayya, D.N.; Puthiyavinayagam, P.; Chellapandi, P.

    2013-01-01

    For a typical MOX fuelled SFR of power reactor size, Implications due to higher burnup have been quantified. Advantages: – Improvement in the economy is seen upto 200 GWd/ t; Disadvantages: – Design changes > 150 GWd/ t bu; – Need for 8/ 16 more fuel SA at 150/ 200 GWd/ t bu; – Higher enrichment of B 4 C in CSR/ DSR at higher bu; – Reduction in LHR may be required at higher bu; – Structural material changes beyond 150 GWd/ t bu; – Reprocessing point of view-Sp Activity & Decay heat increase. Need for R & D is a must before increasing burnup. bu- refers burnup. Efforts to increase MOX fuel burnup beyond 200 GWd/ t may not be highly lucrative; • MOX fuelled FBR would be restricted to two or four further reactors; • Imported MOX fuelled FBRs may be considered; • India looks towards launching metal fuel FBRs in the future. – Due to high Breeding Ratio; – High burnup capability

  17. Achieving High Reliability Operations Through Multi-Program Integration

    Energy Technology Data Exchange (ETDEWEB)

    Holly M. Ashley; Ronald K. Farris; Robert E. Richards

    2009-04-01

    Over the last 20 years the Idaho National Laboratory (INL) has adopted a number of operations and safety-related programs which has each periodically taken its turn in the limelight. As new programs have come along there has been natural competition for resources, focus and commitment. In the last few years, the INL has made real progress in integrating all these programs and are starting to realize important synergies. Contributing to this integration are both collaborative individuals and an emerging shared vision and goal of the INL fully maturing in its high reliability operations. This goal is so powerful because the concept of high reliability operations (and the resulting organizations) is a masterful amalgam and orchestrator of the best of all the participating programs (i.e. conduct of operations, behavior based safety, human performance, voluntary protection, quality assurance, and integrated safety management). This paper is a brief recounting of the lessons learned, thus far, at the INL in bringing previously competing programs into harmony under the goal (umbrella) of seeking to perform regularly as a high reliability organization. In addition to a brief diagram-illustrated historical review, the authors will share the INL’s primary successes (things already effectively stopped or started) and the gaps yet to be bridged.

  18. Telescoping Solar Array Concept for Achieving High Packaging Efficiency

    Science.gov (United States)

    Mikulas, Martin; Pappa, Richard; Warren, Jay; Rose, Geoff

    2015-01-01

    Lightweight, high-efficiency solar arrays are required for future deep space missions using high-power Solar Electric Propulsion (SEP). Structural performance metrics for state-of-the art 30-50 kW flexible blanket arrays recently demonstrated in ground tests are approximately 40 kW/cu m packaging efficiency, 150 W/kg specific power, 0.1 Hz deployed stiffness, and 0.2 g deployed strength. Much larger arrays with up to a megawatt or more of power and improved packaging and specific power are of interest to mission planners for minimizing launch and life cycle costs of Mars exploration. A new concept referred to as the Compact Telescoping Array (CTA) with 60 kW/cu m packaging efficiency at 1 MW of power is described herein. Performance metrics as a function of array size and corresponding power level are derived analytically and validated by finite element analysis. Feasible CTA packaging and deployment approaches are also described. The CTA was developed, in part, to serve as a NASA reference solar array concept against which other proposed designs of 50-1000 kW arrays for future high-power SEP missions could be compared.

  19. Some effects of gas adsorption on the high temperature volatile release behavior of a terrestrial basalt, tektite and lunar soil

    Science.gov (United States)

    Graham, D. G.; Muenow, D. W.; Gibson, E. K., Jr.

    1979-01-01

    Mass pyrograms obtained from high-temperature, mass psectrometric pyrolysis of a glassy theoleiitic submarine basalt and a tektite, ground in air to less than 64 microns, have shown N2 and SO release patterns very similar to those from the pyrolysis of mature lunar soil fines. The N2 and CO release behavior from the terrestrial samples reproduces the biomodal, high-temperature (approximately 700 and 1050 C) features from the lunar samples. Unground portions of the basalt and tektite show no release of N2 and CO during pyrolysis. Grinding also alters the release behavior and absolute amounts of H2O and CO2. It is suggested that adsorption of atmospheric gases in addition to solar wind implantation of ions may account for the wide range of values in previously reported concentrations of carbon and nitrogen from lunar fines.

  20. Vocational High School Students’ Profile and their English Achievement

    Science.gov (United States)

    Liando, N. V. F.; Ratu, D. M.; Sahentombage, V.

    2018-02-01

    Vocational education has been given more attention in Indonesian education in the recent years. There have been many projects for vocational education since Jokowi Widodo took his presidential office in October 2014. In supporting government actions, vocational high school students need to improve their profile. Living in the global worlds requires the ability to interact with people from all over the world. The ability to communicate using English as the lingua franca is important. The purpose of the research reported here is, to prove whether the direct method is effective in improving vocational high school students’ English pronunciation or not. This research design is a true experimental using post-test only. The population is students from one vocational high school in North Sulawesi. Sample of this research was year 11 students consisting of two classes class A (27 students) and class B (27 students). The instrument used in collecting data is tests. The results showed that the mean of the experimental group (36.99) statistically describes the students’ improvement in pronouncing English words in which have been compared by result of the tobserved (2.897) exceed tcritical (1.943) at the level of significance 0.05. It means that there is a significant difference between the mean score of experimental group and control group regarding students’ English pronunciation. This then supports the claim that ‘rejects’ Ho and ‘accept’ Ha. Based on the result, it could be concluded that the direct method is considered effective in improving students’ English pronunciation.

  1. High Achievement in Mathematics Education in India: A Report from Mumbai

    Science.gov (United States)

    Raman, Manya

    2010-01-01

    This paper reports a study aimed at characterizing the conditions that lead to high achievement in mathematics in India. The study involved eight schools in the greater Mumbai region. The main result of the study is that the notion of high achievement itself is problematic, as reflected in the reports about mathematics achievement within and…

  2. Achieving High Accuracy in Calculations of NMR Parameters

    DEFF Research Database (Denmark)

    Faber, Rasmus

    quantum chemical methods have been developed, the calculation of NMR parameters with quantitative accuracy is far from trivial. In this thesis I address some of the issues that makes accurate calculation of NMR parameters so challenging, with the main focus on SSCCs. High accuracy quantum chemical......, but no programs were available to perform such calculations. As part of this thesis the CFOUR program has therefore been extended to allow the calculation of SSCCs using the CC3 method. CC3 calculations of SSCCs have then been performed for several molecules, including some difficult cases. These results show...... vibrations must be included. The calculation of vibrational corrections to NMR parameters has been reviewed as part of this thesis. A study of the basis set convergence of vibrational corrections to nuclear shielding constants has also been performed. The basis set error in vibrational correction...

  3. Achieving high fusion reactivity in high poloidal beta discharges in TFTR

    International Nuclear Information System (INIS)

    Manuel, M.E.; Navratil, G.A.; Sabbagh, S.A.; Batha, S.; Bell, M.G.; Bell, R.; Budny, R.V.; Bush, C.E.; Cavallo, A.; Chance, M.S.; Cheng, C.Z.; Efthimion, P.C.; Fredrickson, E.D.; Fu, G.Y.; Hawryluk, R.J.; Janos, A.C.; Jassby, D.L.; Levinton, F.; Mikkelsen, D.R.; Manickam, J.; McCune, D.C.; McGuire, K.M.; Medley, S.S.; Mueller, D.; Nagayama, Y.; Owens, D.K.; Park, H.K.; Ramsey, A.T.; Stratton, B.C.; Synakowski, E.J.; Taylor, G.; Wieland, R.M.; Yamada, M.; Zarnstorff, M.C.: Zweben, S.; Kesner, J.; Marmar, E.; Snipes, J.; Terry, J.

    1993-04-01

    High poloidal beta discharges have been produced in TFTR that achieved high fusion reactivities at low plasma currents. By rapidly decreasing the plasma current just prior to high-power neutral beam injection, relatively peaked current profiles were created having high l i > 2, high Troyon-normalized beta, βN > 3, and high poloidal beta. β p ≥ 0.7 R/a. The global energy confinement time after the current ramp was comparable to supershots, and the combination of improved MHD stability and good confinement produced a new high εβ p high Q DD operating mode for TFTR. Without steady-state current profile control, as the pulse lengths of high βp discharges were extended, l i decreased, and the improved stability produced immediately after by the current ramp deteriorated. In four second, high εβ p discharges, the current profile broadened under the influence of bootstrap and beam-drive currents. When the calculated voltage throughout the plasma nearly vanished, MHD instabilities were observed with β N as low as 1.4. Ideal MHD stability calculations showed this lower beta limit to be consistent with theoretical expectations

  4. Not all trees sleep the same - High temporal resolution terrestrial laser scanning shows differences in nocturnal plant movement

    DEFF Research Database (Denmark)

    Zlinszky, András; Barfod, Anders; Molnár, Bence

    2017-01-01

    Circadian leaf movements are widely known in plants, but nocturnal movement of tree branches were only recently discovered by using terrestrial laser scanning (TLS), a high resolution three-dimensional surveying technique. TLS uses a pulsed laser emitted in a regular scan pattern for rapid...... surveyed a series of 18 full scans over a 12-h night period to measure nocturnal changes in shape simultaneously for an experimental setup of 22 plants representing different species. Resulting point clouds were evaluated by comparing changes in height percentiles of laser scanning points belonging...... to the canopy. Changes in crown shape were observed for all studied trees, but clearly distinguishable sleep movements are apparently rare. Ambient light conditions were continuously dark between sunset (7:30 p.m.) and sunrise (6:00 a.m.), but most changes in movement direction occurred during this period, thus...

  5. COMPARATIVE PERSPECTIVES OF STUDY STRATEGIES AMONG HIGH AND LOW ACHIEVERS DISTANCE LEARNING STUDENTS

    Directory of Open Access Journals (Sweden)

    Muhammad Imran YOUSUF

    2009-07-01

    Full Text Available The main aim of this research is to better understand and draw perceptions of low and high achiever distance learners about their study patterns. The study indicates the areas where significant difference is found among low and high achievers of Allama Iqbal Open University, Pakistan through a self developed questionnaire covering their preferred study location, study times, number of hours spent on study, the difficulties affecting their study patterns and the organization of study strategies in comparative perspective. Greater difficulties were being faced by low achievers in their study. Increased difficulties were encountered by low achievers with study material, volume of study, self-motivation and other factors. There was no significant difference between low and high achievers for their study strategies of studying materials without taking notes and reading aloud. Greater low achievers attempted easy portions of their study material first and took notes simultaneously as compared to high achievers.

  6. Rapid, high-resolution measurement of leaf area and leaf orientation using terrestrial LiDAR scanning data

    International Nuclear Information System (INIS)

    Bailey, Brian N; Mahaffee, Walter F

    2017-01-01

    The rapid evolution of high performance computing technology has allowed for the development of extremely detailed models of the urban and natural environment. Although models can now represent sub-meter-scale variability in environmental geometry, model users are often unable to specify the geometry of real domains at this scale given available measurements. An emerging technology in this field has been the use of terrestrial LiDAR scanning data to rapidly measure the three-dimensional geometry of trees, such as the distribution of leaf area. However, current LiDAR methods suffer from the limitation that they require detailed knowledge of leaf orientation in order to translate projected leaf area into actual leaf area. Common methods for measuring leaf orientation are often tedious or inaccurate, which places constraints on the LiDAR measurement technique. This work presents a new method to simultaneously measure leaf orientation and leaf area within an arbitrarily defined volume using terrestrial LiDAR data. The novelty of the method lies in the direct measurement of the fraction of projected leaf area G from the LiDAR data which is required to relate projected leaf area to total leaf area, and in the new way in which radiation transfer theory is used to calculate leaf area from the LiDAR data. The method was validated by comparing LiDAR-measured leaf area to (1) ‘synthetic’ or computer-generated LiDAR data where the exact area was known, and (2) direct measurements of leaf area in the field using destructive sampling. Overall, agreement between the LiDAR and reference measurements was very good, showing a normalized root-mean-squared-error of about 15% for the synthetic tests, and 13% in the field. (paper)

  7. Does High School Facility Quality Affect Student Achievement? A Two-Level Hierarchical Linear Model

    Science.gov (United States)

    Bowers, Alex J.; Urick, Angela

    2011-01-01

    The purpose of this study is to isolate the independent effects of high school facility quality on student achievement using a large, nationally representative U.S. database of student achievement and school facility quality. Prior research on linking school facility quality to student achievement has been mixed. Studies that relate overall…

  8. JOINT PROCESSING OF UAV IMAGERY AND TERRESTRIAL MOBILE MAPPING SYSTEM DATA FOR VERY HIGH RESOLUTION CITY MODELING

    Directory of Open Access Journals (Sweden)

    A. Gruen

    2013-08-01

    Full Text Available Both unmanned aerial vehicle (UAV technology and Mobile Mapping Systems (MMS are important techniques for surveying and mapping. In recent years, the UAV technology has seen tremendous interest, both in the mapping community and in many other fields of application. Carrying off-the shelf digital cameras, the UAV can collect high quality aerial optical images for city modeling using photogrammetric techniques. In addition, a MMS can acquire high density point clouds of ground objects along the roads. The UAV, if operated in an aerial mode, has difficulties in acquiring information of ground objects under the trees and along façades of buildings. On the contrary, the MMS collects accurate point clouds of objects from the ground, together with stereo images, but it suffers from system errors due to loss of GPS signals, and also lacks the information of the roofs. Therefore, both technologies are complementary. This paper focuses on the integration of UAV images, MMS point cloud data and terrestrial images to build very high resolution 3D city models. The work we will show is a practical modeling project of the National University of Singapore (NUS campus, which includes buildings, some of them very high, roads and other man-made objects, dense tropical vegetation and DTM. This is an intermediate report. We present work in progress.

  9. Approaches to achieve high grain yield and high resource use efficiency in rice

    Directory of Open Access Journals (Sweden)

    Jianchang YANG

    2015-06-01

    Full Text Available This article discusses approaches to simultaneously increase grain yield and resource use efficiency in rice. Breeding nitrogen efficient cultivars without sacrificing rice yield potential, improving grain fill in later-flowering inferior spikelets and enhancing harvest index are three important approaches to achieving the dual goal of high grain yield and high resource use efficiency. Deeper root distribution and higher leaf photosynthetic N use efficiency at lower N rates could be used as selection criteria to develop N-efficient cultivars. Enhancing sink activity through increasing sugar-spikelet ratio at the heading time and enhancing the conversion efficiency from sucrose to starch though increasing the ratio of abscisic acid to ethylene in grains during grain fill could effectively improve grain fill in inferior spikelets. Several practices, such as post-anthesis controlled soil drying, an alternate wetting and moderate soil drying regime during the whole growing season, and non-flooded straw mulching cultivation, could substantially increase grain yield and water use efficiency, mainly via enhanced remobilization of stored carbon from vegetative tissues to grains and improved harvest index. Further research is needed to understand synergistic interaction between water and N on crop and soil and the mechanism underlying high resource use efficiency in high-yielding rice.

  10. Carbon dioxide exchange in the High Arctic - examples from terrestrial ecosystems

    DEFF Research Database (Denmark)

    Grøndahl, L.

    of the growing season, which in combination with high temperatures increased uptake rates. The dry heath ecosystem in general gained carbon during the summer season in the order of magnitude -1.4 gCm-2 up to 32 gCm-2. This result is filling out a gap of knowledge on the response of high Arctic ecosystems...... the measurements conducted in the valley to a regional level. Including information on temporal and spatial variability in air temperature and radiation, together with NDVI and a vegetation map a regional estimate of the CO2 exchange during the summer was provided, elaborating the NDVI based estimate on net carbon...

  11. International note: between-domain relations of Chinese high school students' academic achievements.

    Science.gov (United States)

    Yangyang, Liu

    2012-08-01

    The present study examined the between-domain relations of Chinese high school students' academic achievements. In a sample of 1870 Chinese 10th grade students, the results indicated that Chinese high school students' academic achievements were correlated across nine subjects. In line with the previous Western findings, the findings suggested that academic achievement was largely domain-general in nature. Copyright © 2012 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  12. An Analysis of Java Programming Behaviors, Affect, Perceptions, and Syntax Errors among Low-Achieving, Average, and High-Achieving Novice Programmers

    Science.gov (United States)

    Rodrigo, Ma. Mercedes T.; Andallaza, Thor Collin S.; Castro, Francisco Enrique Vicente G.; Armenta, Marc Lester V.; Dy, Thomas T.; Jadud, Matthew C.

    2013-01-01

    In this article we quantitatively and qualitatively analyze a sample of novice programmer compilation log data, exploring whether (or how) low-achieving, average, and high-achieving students vary in their grasp of these introductory concepts. High-achieving students self-reported having the easiest time learning the introductory programming…

  13. The One to Multiple Automatic High Accuracy Registration of Terrestrial LIDAR and Optical Images

    Science.gov (United States)

    Wang, Y.; Hu, C.; Xia, G.; Xue, H.

    2018-04-01

    The registration of ground laser point cloud and close-range image is the key content of high-precision 3D reconstruction of cultural relic object. In view of the requirement of high texture resolution in the field of cultural relic at present, The registration of point cloud and image data in object reconstruction will result in the problem of point cloud to multiple images. In the current commercial software, the two pairs of registration of the two kinds of data are realized by manually dividing point cloud data, manual matching point cloud and image data, manually selecting a two - dimensional point of the same name of the image and the point cloud, and the process not only greatly reduces the working efficiency, but also affects the precision of the registration of the two, and causes the problem of the color point cloud texture joint. In order to solve the above problems, this paper takes the whole object image as the intermediate data, and uses the matching technology to realize the automatic one-to-one correspondence between the point cloud and multiple images. The matching of point cloud center projection reflection intensity image and optical image is applied to realize the automatic matching of the same name feature points, and the Rodrigo matrix spatial similarity transformation model and weight selection iteration are used to realize the automatic registration of the two kinds of data with high accuracy. This method is expected to serve for the high precision and high efficiency automatic 3D reconstruction of cultural relic objects, which has certain scientific research value and practical significance.

  14. Experiences of families with a high-achiever child in sport: Case ...

    African Journals Online (AJOL)

    The family, not only the coach, plays a major role in the pursuit of children to reach the highest level in sport. Yet, it is mainly the high achiever, and sometimes the coach, who get recognition for success in this regard. This study explored the experiences of families with high-achieving adolescent athletes aspiring to compete ...

  15. The Effect of the Time Management Art on Academic Achievement among High School Students in Jordan

    Science.gov (United States)

    Al-Zoubi, Maysoon

    2016-01-01

    This study aimed at recognizing the effect of the Time Management Art on academic achievement among high school students in the Hashemite Kingdom of Jordan. The researcher employed the descriptive-analytic research to achieve the purpose of the study where he chose a sample of (2000) high school female and male students as respondents to the…

  16. Comparison of the dynamical processes in plasma turbulence observed in the high- and low-β regions of the terrestrial foreshock

    International Nuclear Information System (INIS)

    Coca, D.; Balikhin, M.; Billings, S.

    2001-01-01

    This paper highlights the fact that the dynamical processes that characterise plasma turbulence observed in the high-β region of the terrestrial foreshock are significantly different from the dynamical processes identified in the low-β region. The study is based on a time-domain model identified from measurements taken by AMPTE-UKS and AMPTE-IRM satellites. (author)

  17. Comparison of the dynamical processes in plasma turbulence observed in the high- and low-{beta} regions of the terrestrial foreshock

    Energy Technology Data Exchange (ETDEWEB)

    Coca, D.; Balikhin, M.; Billings, S

    2001-06-01

    This paper highlights the fact that the dynamical processes that characterise plasma turbulence observed in the high-{beta} region of the terrestrial foreshock are significantly different from the dynamical processes identified in the low-{beta} region. The study is based on a time-domain model identified from measurements taken by AMPTE-UKS and AMPTE-IRM satellites. (author)

  18. The alien terrestrial invertebrate fauna of the High Arctic archipelago of Svalbard: potential implications for the native flora and fauna

    OpenAIRE

    Stephen J. Coulson

    2015-01-01

    Experience from the Antarctic indicates that the establishment of alien species may have significant negative effects on native flora and fauna in polar regions and is considered to be amongst the greatest threats to biodiversity. But, there have been few similar studies from the Arctic. Although the terrestrial invertebrate inventory of the Svalbard Archipelago is amongst the most complete for any region of the Arctic, no consideration has yet been made of alien terrestrial invertebrate spec...

  19. New optical sensor systems for high-resolution satellite, airborne and terrestrial imaging systems

    Science.gov (United States)

    Eckardt, Andreas; Börner, Anko; Lehmann, Frank

    2007-10-01

    The department of Optical Information Systems (OS) at the Institute of Robotics and Mechatronics of the German Aerospace Center (DLR) has more than 25 years experience with high-resolution imaging technology. The technology changes in the development of detectors, as well as the significant change of the manufacturing accuracy in combination with the engineering research define the next generation of spaceborne sensor systems focusing on Earth observation and remote sensing. The combination of large TDI lines, intelligent synchronization control, fast-readable sensors and new focal-plane concepts open the door to new remote-sensing instruments. This class of instruments is feasible for high-resolution sensor systems regarding geometry and radiometry and their data products like 3D virtual reality. Systemic approaches are essential for such designs of complex sensor systems for dedicated tasks. The system theory of the instrument inside a simulated environment is the beginning of the optimization process for the optical, mechanical and electrical designs. Single modules and the entire system have to be calibrated and verified. Suitable procedures must be defined on component, module and system level for the assembly test and verification process. This kind of development strategy allows the hardware-in-the-loop design. The paper gives an overview about the current activities at DLR in the field of innovative sensor systems for photogrammetric and remote sensing purposes.

  20. Coexistence Performance of High-Altitude Platform and Terrestrial Systems Using Gigabit Communication Links to Serve Specialist Users

    Directory of Open Access Journals (Sweden)

    Peng Z

    2008-01-01

    Full Text Available Abstract This paper presents three feasible methods to serve specialist users within a service area of up to 150 km diameter by using spot-beam gigabit wireless communication links from high-altitude platforms (HAPs. A single HAP serving multiple spot beams coexists with terrestrial systems, all sharing a common frequency band. The schemes provided in the paper are used to adjust the pointing direction of aperture antennas operating in the mm-wave bands, such that the peak carrier to interference plus noise ratio (CINR is delivered directly toward the location of the specialist users; the schemes include the small step size scheme, half distance scheme, and beam switch scheme. The pointing process is controlled iteratively using the mean distance between the peak CINR locations and user positions. The paper shows that both the small step size and half distance schemes significantly enhance the CINR at the user, but performance is further improved if beams with adverse performance below a specific threshold are switched off, or are assigned another channel.

  1. Coexistence Performance of High-Altitude Platform and Terrestrial Systems Using Gigabit Communication Links to Serve Specialist Users

    Directory of Open Access Journals (Sweden)

    D. Grace

    2008-10-01

    Full Text Available This paper presents three feasible methods to serve specialist users within a service area of up to 150 km diameter by using spot-beam gigabit wireless communication links from high-altitude platforms (HAPs. A single HAP serving multiple spot beams coexists with terrestrial systems, all sharing a common frequency band. The schemes provided in the paper are used to adjust the pointing direction of aperture antennas operating in the mm-wave bands, such that the peak carrier to interference plus noise ratio (CINR is delivered directly toward the location of the specialist users; the schemes include the small step size scheme, half distance scheme, and beam switch scheme. The pointing process is controlled iteratively using the mean distance between the peak CINR locations and user positions. The paper shows that both the small step size and half distance schemes significantly enhance the CINR at the user, but performance is further improved if beams with adverse performance below a specific threshold are switched off, or are assigned another channel.

  2. Unforgiving Confucian Culture: A Breeding Ground for High Academic Achievement, Test Anxiety and Self-Doubt?

    Science.gov (United States)

    Stankov, Lazar

    2010-01-01

    This paper reviews findings from several studies that contribute to our understanding of cross-cultural differences in academic achievement, anxiety and self-doubt. The focus is on comparisons between Confucian Asian and European regions. Recent studies indicate that high academic achievement of students from Confucian Asian countries is…

  3. Instructional, Transformational, and Managerial Leadership and Student Achievement: High School Principals Make a Difference

    Science.gov (United States)

    Valentine, Jerry W.; Prater, Mike

    2011-01-01

    This statewide study examined the relationships between principal managerial, instructional, and transformational leadership and student achievement in public high schools. Differences in student achievement were found when schools were grouped according to principal leadership factors. Principal leadership behaviors promoting instructional and…

  4. Low and High Mathematics Achievement in Japanese, Chinese, and American Elementary-School Children.

    Science.gov (United States)

    Uttal, David H.; And Others

    1988-01-01

    First and fifth grade students who scored high or low on a mathematics test were tested for intellectual ability and reading achievement. Students and their mothers were interviewed. Results indicated that factors associated with levels of achievement in mathematics operate in a similar fashion across three cultures that differ greatly in their…

  5. The Role of Principal Leadership in Achievement beyond Test Scores: An Examination of Leadership, Differentiated Curriculum and High-Achieving Students

    Science.gov (United States)

    Else, Danielle F.

    2013-01-01

    Though research has validated a link between principal leadership and student achievement, questions remain regarding the specific relationship between the principal and high-achieving learners. This association facilitates understanding about forming curricular decisions for high ability learners. The study was conducted to examine the perceived…

  6. Terrestrial ecology

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The main effort of the Terrestrial Ecology Division has been redirected to a comprehensive study of the Espiritu Santo Drainage Basin located in northeastern Puerto Rico. The general objective are to provide baseline ecological data for future environmental assessment studies at the local and regional levels, and to provide through an ecosystem approach data for the development of management alternatives for the wise utilization of energy, water, and land resources. The interrelationships among climate, vegetation, soils, and man, and their combined influence upon the hydrologic cycle will be described and evaluated. Environmental management involves planning and decision making, and both require an adequate data base. At present, little is known about the interworkings of a complete, integrated system such as a drainage basin. A literature survey of the main research areas confirmed that, although many individual ecologically oriented studies have been carried out in a tropical environment, few if any provide the data base required for environmental management. In view of rapidly changing socio-economic conditions and natural resources limitations, management urgently requires data from these systems: physical (climatological), biological, and cultural. This integrated drainage basin study has been designed to provide such data. The scope of this program covers the hydrologic cycle as it is affected by the interactions of the physical, biological, and cultural systems

  7. High-resolution Atmospheric pCO2 Reconstruction across the Paleogene Using Marine and Terrestrial δ13C records

    Science.gov (United States)

    Cui, Y.; Schubert, B.

    2016-02-01

    The early Paleogene (63 to 47 Ma) is considered to have a greenhouse climate1 with proxies suggesting atmospheric CO2 levels (pCO2) approximately 2× pre-industrial levels. However, the proxy based pCO2 reconstructions are limited and do not allow for assessment of changes in pCO2 at million to sub-million year time scales. It has recently been recognized that changes in C3 land plant carbon isotope fractionation can be used as a proxy for pCO2 with quantifiable uncertainty2. Here, we present a high-resolution pCO2 reconstruction (n = 597) across the early Paleogene using published carbon isotope data from both terrestrial organic matter and marine carbonates. The minimum and maximum pCO2 values reconstructed using this method are broad (i.e., 170 +60/-40 ppmv to 2000 +4480/-1060 ppmv) and reflective of the wide range of environments sampled. However, the large number of measurements allows for a robust estimate of average pCO2 during this time interval ( 400 +260/-120 ppmv), and indicates brief (sub-million-year) excursions to very high pCO2 during hyperthermal events (e.g., the PETM). By binning our high-resolution pCO2 data at 1 million year intervals, we can compare our dataset to the other available pCO2 proxies. Our result is broadly consistent with pCO2 levels reconstructed using other proxies, with the exception of paleosol-based pCO2 estimates spanning 53 to 50 Ma. At this timescale, no proxy suggests pCO2 higher than 2000 ppmv, whereas the global surface ocean temperature is considered to be >10 oC warmer than today. Recent climate modeling suggests that low atmospheric pressure during this time period could help reconcile the apparent disconnect between pCO2 and temperature and contribute to the greenhouse climate3. References1. Huber, M., Caballero, R., 2011. Climate of the Past 7, 603-633. 2. Schubert, B.A., Jahren, A.H., 2015. Geology 43, 435-438. 3. Poulsen, C.J., Tabor, C., White, J.D., 2015. Science 348, 1238-1241.

  8. Resilience influence, goals and social context in the academic achievement of high school students

    Directory of Open Access Journals (Sweden)

    José Concepción Gaxiola Romero

    2012-05-01

    Full Text Available The academic achievement in high school students of Mexico, according to national and international evaluations has been insufficient. In spite of this situation, is possible to find excellent students, even in the context of sharing negative contextual and physical conditions. There are few investigations that describe the variables associated to resilient students. The alumni that are beyond the risks are called resilient (Rutter, 2007. The aim of this research was to explore and identify the internal variables: goals and resilience, and the external variables: risky neighborhood and risky friends that predicted the scholar achievement of high school students. To measure those variables, was used a compilation of scales validated in the region. The data were analyzed using structural equation modeling, and show that resilience predicted indirectly the scholar achievement trough the academic goals. The results could be used in programs to improve the academic achievement of this group of students.

  9. Recording Approach of Heritage Sites Based on Merging Point Clouds from High Resolution Photogrammetry and Terrestrial Laser Scanning

    Science.gov (United States)

    Grussenmeyer, P.; Alby, E.; Landes, T.; Koehl, M.; Guillemin, S.; Hullo, J. F.; Assali, P.; Smigiel, E.

    2012-07-01

    Different approaches and tools are required in Cultural Heritage Documentation to deal with the complexity of monuments and sites. The documentation process has strongly changed in the last few years, always driven by technology. Accurate documentation is closely relied to advances of technology (imaging sensors, high speed scanning, automation in recording and processing data) for the purposes of conservation works, management, appraisal, assessment of the structural condition, archiving, publication and research (Patias et al., 2008). We want to focus in this paper on the recording aspects of cultural heritage documentation, especially the generation of geometric and photorealistic 3D models for accurate reconstruction and visualization purposes. The selected approaches are based on the combination of photogrammetric dense matching and Terrestrial Laser Scanning (TLS) techniques. Both techniques have pros and cons and recent advances have changed the way of the recording approach. The choice of the best workflow relies on the site configuration, the performances of the sensors, and criteria as geometry, accuracy, resolution, georeferencing, texture, and of course processing time. TLS techniques (time of flight or phase shift systems) are widely used for recording large and complex objects and sites. Point cloud generation from images by dense stereo or multi-view matching can be used as an alternative or as a complementary method to TLS. Compared to TLS, the photogrammetric solution is a low cost one, as the acquisition system is limited to a high-performance digital camera and a few accessories only. Indeed, the stereo or multi-view matching process offers a cheap, flexible and accurate solution to get 3D point clouds. Moreover, the captured images might also be used for models texturing. Several software packages are available, whether web-based, open source or commercial. The main advantage of this photogrammetric or computer vision based technology is to get

  10. What Leadership Behaviors Were Demonstrated by the Principal in a High Poverty, High Achieving Elementary School?

    Science.gov (United States)

    Woods, E. Hayet J.; Martin, Barbara N.

    2016-01-01

    Examined through the lens of leadership, were the behaviors of a principal as perceived by stakeholders. The following themes emerged: (1) Educating the Whole Child, with the subthemes: (a) providing basic needs; (b) academic interventions based on achievement data; (c) an emphasis on reading; (d) extended academic time; and (e) relationships; and…

  11. Teacher Classroom Practices, Student Motivation and Mathematics Achievements in High School: Evidence from HSLS:09 Data

    OpenAIRE

    Yu, Rongrong

    2015-01-01

    The present study explored the direct influences of teacher classroom practices, including teacher support, conceptual teaching, and procedural teaching, on 9th grade students' mathematics achievement, and the indirect influences of these teacher variables on student mathematics achievement through students' mathematics self-efficacy and interest in mathematics courses. The base year data of High School Longitudinal Study of 2009 (HSLS: 09) was used for this study. Structural equation modelin...

  12. Teacher Support, Instructional Practices, Student Motivation, and Mathematics Achievement in High School

    Science.gov (United States)

    Yu, Rongrong; Singh, Kusum

    2018-01-01

    The authors examined the relationships among teacher classroom practices, student motivation, and mathematics achievement in high school. The data for this study was drawn from the base-year data of High School Longitudinal Study of 2009. Structural equation modeling method was used to estimate the relationships among variables. The results…

  13. Mathematics Achievement with Digital Game-Based Learning in High School Algebra 1 Classes

    Science.gov (United States)

    Ferguson, Terri Lynn Kurley

    2014-01-01

    This study examined the impact of digital game-based learning (DGBL) on mathematics achievement in a rural high school setting in North Carolina. A causal comparative research design was used in this study to collect data to determine the effectiveness of DGBL in high school Algebra 1 classes. Data were collected from the North Carolina…

  14. Family Processes Affect Students' Motivation, and Science and Math Achievement in Cypriot High Schools.

    Science.gov (United States)

    Koutsoulis, Michalis K.; Campbell, James Reed

    2001-01-01

    Studied the influence of home environment on male and female high school students' motivation and achievement. Results for 737 Cypriot high school students and their parents show the importance of student self-concept and negative effects for parental pressure. Results suggest the need for closer lines of communication between home and school.…

  15. Closing the Mathematics Achievement Gap in High-Poverty Middle Schools: Enablers and Constraints

    Science.gov (United States)

    Balfanz, Robert; Byrnes, Vaughan

    2006-01-01

    The mathematics achievement levels of U.S. students fall far behind those of other developed nations; within the United States itself, the students who are falling behind come predominantly from high-poverty and high-minority areas. This article reports on a series of analyses that followed 4 cohorts of students from 3 such schools through the 5th…

  16. A Case Study of 21st Century Skills in High Achieving Elementary Schools in Pennsylvania

    Science.gov (United States)

    Egnor, Gregory P.

    2013-01-01

    This study examines if practices that advocate for 21st century skills are in conflict with the mandates of NCLB. Interviews with influential school leaders of high achieving elementary schools focused on collecting data about 21st century skills. This study was designed to (a) Determine if 21st century skills are addressed in high achieving…

  17. Application of Terrestrial Ecosystem Monitoring under the CAFF Circumpolar Biodiversity Monitoring Program: Designing and Implementing Terrestrial Monitoring to Establish the Canadian High Arctic Research Station as a Flagship Arctic Environmental Monitoring Site

    Science.gov (United States)

    McLennan, D.; Kehler, D.

    2016-12-01

    The Canadian High Arctic Research Station (CHARS) is scheduled for completion in July 2017 and is the northern science component of Polar Knowledge Canada (POLAR). A mandated goal for POLAR is to establish the adjacent Experimental and Reference Area (ERA) as an Arctic Flagship monitoring site that will track change in Arctic terrestrial, freshwater and marine ecosystems. Situated in the community of Cambridge Bay, CHARS provides the opportunity to draw on the Indigenous Knowledge of local residents to help design and conduct the monitoring, and to operate 12 months a year. Monitoring at CHARS will be linked to networks nationally and internationally, and is being designed so that change in key indicators can be understood in terms of drivers and processes, modeled and scaled up regionally, and used to predict important changes in critical indicators. As a partner in the Circumpolar Biodiversity Monitoring Program (CBMP), the monitoring design for terrestrial ecosystems follows approaches outlined by the CBMP Terrestrial Expert Monitoring Group, who have listed key monitoring questions and identified a list of important Focal Ecosystem Components (FECs). To link drivers to FECs we are proposing a multi-scaled approach: 1) an Intensive Monitoring Area to establish replicated monitoring plots that track change in snow depth and condition, active layer depth, soil temperature, soil moisture, and soil solution chemistry that are spatially and temporally linked to changes in microbiological activity, CO2/CH4 net ecosystem flux, vegetation relative frequency, species composition, growth and foliar nutrient concentration, arthropod abundance, lemming abundance and health, and shorebird/songbird abundance and productivity. 2) These intensive observations are supported by watershed scale measures that will monitor, during the growing season, lemming winter nest abundance, songbird, shorebird and waterfowl staging and nesting, and other observations; in the winter we will

  18. What leadership behaviors were demonstrated by the principal in a high poverty, high achieving elementary school?

    Directory of Open Access Journals (Sweden)

    E. Hayet J. Woods

    2016-12-01

    Full Text Available Examined through the lens of leadership, were the behaviors of a principal as perceived by stakeholders. The following themes emerged: (1 Educating the Whole Child, with the subthemes: (a providing basic needs; (b academic interventions based on achievement data; (c an emphasis on reading; (d extended academic time; and (e relationships; and (2 Synergy of Expectations, with the subthemes: (a consistent student expectations; (b increased staff accountability; and (c community involvement. The researchers found that the principal by demonstrating behaviors as a change agent, a creator of vision, and a provider of necessary support and strategies, rather than adopting numerous programs, the school personnel were able to increase and sustain academic achievement of the students of poverty as well as their peers. Implications for principal practices, along with leadership preparatory programs are significant.

  19. Unexpected High Diversity of Terrestrial Cyanobacteria from the Campus of the University of the Ryukyus, Okinawa, Japan

    Directory of Open Access Journals (Sweden)

    Xuan Hoa Nguyen

    2017-11-01

    Full Text Available Terrestrial cyanobacterial strains were isolated from the Nishihara campus of the University of the Ryukyus, Okinawa, Japan. The 13 sampling sites were distributed in a 200 m radius and appeared as dry, blackened stains. From these small areas, 143 cyanobacterial strains were established. The strains were divided into five morphotypes, including unicells, unicells with baeocytes, non-branching filaments, false-branching filaments, and heterocystous strains. From the strains, 105 partial 16S rRNA gene sequences were obtained and could be classified into 30 generic types. Among them, 22 unique strains and over 1100 bps of data were selected for further phylogenetic analyses. These sequences were positioned into six main clades corresponding to cyanobacterial orders: Nostocales, Chroococidiopsidales, Chroococcales, Oscillatoriales, Pleurocapsales, and Synechococcales. Almost all sequences had no identical matching data in GenBank and many of them had no closely related data. These data suggest that the terrestrial cyanobacteria are very divese even within close sampling areas, such as within the campus of the University of the Ryukyus. The established strains are not only important for classification of terrestrial cyanobacteria but also for possible application studies in the future.

  20. "It's a Way of Life for Us": High Mobility and High Achievement in Department of Defense Schools.

    Science.gov (United States)

    Smrekar, Claire E.; Owens, Debra E.

    2003-01-01

    Examines the academic performance of students in U.S. Department of Defense Education Activity (DoDEA) schools, which have high student mobility. Some observers contend that these students' high achievement is a function of their middle class family and community characteristics. Asserts that DoDEA schools simultaneously "do the right…

  1. Mo' Money, Mo' Problems? High-Achieving Black High School Students' Experiences with Resources, Racial Climate, and Resilience

    Science.gov (United States)

    Allen, Walter; Griffin, Kimberly

    2006-01-01

    A multi-site case study analyzed the college preparatory processes of nine African American high achievers attending a well-resourced, suburban high school and eight academically successful African Americans attending a low-resourced urban school. Students at both schools experienced barriers, that is, racial climate and a lack of resources, that…

  2. 2×2 dominant achievement goal profiles in high-level swimmers.

    Science.gov (United States)

    Fernandez-Rio, Javier; Cecchini Estrada, Jose A; Mendez-Giménez, Antonio; Fernández-Garcia, Benjamín; Saavedra, Pablo

    2014-01-01

    The goal of this study was to assess achievement goal dominance, self-determined situational motivation and competence in high-level swimmers before and after three training sessions set at different working intensities (medium, sub-maximal and maximal). Nineteen athletes (males, n=9, 18.00±2.32 years; females, n=10, 16.30±2.01 years, range = 14-18) agreed to participate. They completed a questionnaire that included the Dominant Achievement Goal assessment instrument, the 2×2 Achievement Goals Questionnaire for Sport (AGQ-S), The Situational Motivation Scale (SIMS) and the Competence subscale of the Basic Psychological Needs in Exercise questionnaire (BPNES). Results indicated that participants overwhelmingly showed mastery-approach achievement goal dominance, and it remained stable at the conclusion of the different training sessions under all intensity levels. This profile was positively correlated to self-determined situational motivation and competence. However, swimmers' feelings of competence increased only after the medium intensity level training session. After the completion of the maximal intensity training session, swimmers' self-determined motivation was significantly lower compared to the other two training sessions, which could be caused by a temporary period of burnout. Results indicated that high-level swimmers had a distinct mastery-approach dominant achievement goal profile that was not affected by the workload of the different training sessions. They also showed high levels of self-determined situational motivation and competence. However, heavy workloads should be controlled because they can cause transitory burnout.

  3. Islamic Senior High School Students’ Language Learning Strategies and their English Achievement

    Directory of Open Access Journals (Sweden)

    ISTI QOMARIAH

    2018-05-01

    Full Text Available This study investigated the correlation between language learning strategies and English achievement, and explored the influence of language learning strategies on English achievement of eleventh grade students’ of MAN 3 Palembang. A total of 141 eleventh grade students participated in this study. The questionnaire and test were used to collect the data. For this purpose, the language learning strategies (SILL questionnaire developed by Oxford (1989 measured language learning strategies and TOEFL junior (2015 was used to know students’ English achievement. There were three levels from high to low based on the results of SILL questionnaire and five categories English achievement test. Descriptive stastistic, pearson product moment correlation and regression anlaysis were employed to analyze the data. Based on the data analysis, it was found that r (.665 > rtable (.165 with significant level which was lower than 0.05. Thus, it indicated that there was significant correlation between language learning strategies and English achievement. It was implied that good language learners caused good in English achievement.

  4. Perfectionism in High-Ability Students: Relational Precursors and Influences on Achievement Motivation

    Science.gov (United States)

    Speirs Neumeister, Kristie L.; Finch, Holmes

    2006-01-01

    The purpose of the present study was to create and test a model that (a) illustrated variables influencing the development of perfectionism, and (b) demonstrated how different types of perfectionism may influence the achievement goals of high-ability students. Using a multiple groups path analysis, the researchers found that parenting style was…

  5. Antecedent and Concurrent Psychosocial Skills That Support High Levels of Achievement within Talent Domains

    Science.gov (United States)

    Olszewski-Kubilius, Paula; Subotnik, Rena F.; Worrell, Frank C.

    2015-01-01

    Motivation and emotional regulation are important for the sustained focused study and practice required for high levels of achievement and creative productivity in adulthood. Using the talent development model proposed by the authors as a framework, the authors discuss several important psychosocial skills based on the psychological research…

  6. High School Success: An Effective Intervention for Achievement and Dropout Prevention

    Science.gov (United States)

    Lowder, Christopher Michael

    2012-01-01

    The purpose of this mixed-design study was to use quantitative and qualitative research to explore the effects of High School Success (a course for at-risk ninth graders) and its effectiveness on student achievement, attendance, and dropout prevention. The research questions address whether there is a significant difference between at-risk ninth…

  7. Ugandan Immigrant Students' Perceptions of Barriers to Academic Achievement in American High Schools

    Science.gov (United States)

    Ssekannyo, Denis

    2010-01-01

    In a world that is now a global village, enterprising individuals, especially from Third World countries, who make it to greener pastures do not leave their children behind. But with a long list of barriers to academic achievement associated with immigrant and minority students in American high schools, an understanding of the experiences and…

  8. Social Media Use, Loneliness, and Academic Achievement: A Correlational Study with Urban High School Students

    Science.gov (United States)

    Neto, Roque; Golz, Nancy; Polega, Meaghan

    2015-01-01

    This study explored the association between social media use, loneliness, and academic achievement in high school students and identified the demographic characteristics associated with these three elements. This study also aimed to identify the percentage of variance in loneliness accounted for by social media use and GPA. Participants were 345…

  9. What Contributes to Gifted Adolescent Females' Talent Development at a High-Achieving, Secondary Girls' School?

    Science.gov (United States)

    Tweedale, Charlotte; Kronborg, Leonie

    2015-01-01

    The purpose of this research was to examine what contributes to gifted adolescent females' talent development at a high-achieving girls' school. Using Kronborg's (2010) Talent Development Model for Eminent Women as a theoretical framework, this research examined the conditions that supported and those that hindered the participants' talent…

  10. The Effect of Technology Integration on High School Students' Literacy Achievement

    Science.gov (United States)

    Robinson, Kara

    2016-01-01

    This literature review presents a critical appraisal of current research on the role technology integration plays in high school students' literacy achievement. It identifies the gaps within the research through comprehensive analysis. The review develops an argument that the use of laptops in secondary English classrooms has a significant impact…

  11. Comparing Computer Game and Traditional Lecture Using Experience Ratings from High and Low Achieving Students

    Science.gov (United States)

    Grimley, Michael; Green, Richard; Nilsen, Trond; Thompson, David

    2012-01-01

    Computer games are purported to be effective instructional tools that enhance motivation and improve engagement. The aim of this study was to investigate how tertiary student experiences change when instruction was computer game based compared to lecture based, and whether experiences differed between high and low achieving students. Participants…

  12. Students' High School Organizational Leadership Opportunities and Their Influences on Academic Achievement and Civic Participation

    Science.gov (United States)

    Elemen, Jennifer E.

    2015-01-01

    The purpose of this quantitative study was to analyze high school leadership praxis for its inclusion of students in organizational leadership dialogue and decision-making and the influences of these factors on student achievement and civic participation. Survey questionnaire data were provided by 215 full-time enrolled undergraduate students from…

  13. Experiencing More Mathematics Anxiety than Expected? Contrasting Trait and State Anxiety in High Achieving Students

    Science.gov (United States)

    Roos, A.-L.; Bieg, M.; Goetz, T.; Frenzel, A. C.; Taxer, J.; Zeidner, M.

    2015-01-01

    This study examined mathematics anxiety among high and low achieving students (N = 237, grades 9 and 10) by contrasting trait (habitual) and state (momentary) assessments of anxiety. Previous studies have found that trait anxiety measures are typically rated higher than state measures. Furthermore, the academic self-concept has been identified to…

  14. Spatial Experiences of High Academic Achievers: Insights from a Developmental Perspective

    Science.gov (United States)

    Weckbacher, Lisa Marie; Okamoto, Yukari

    2012-01-01

    The study explored the relationship between types of spatial experiences and spatial abilities among 13- to 14-year-old high academic achievers. Each participant completed two spatial tasks and a survey assessing favored spatial activities across five categories (computers, toys, sports, music, and art) and three developmental periods (early…

  15. The Impact of High School Exit Exams on Graduation Rates and Achievement

    Science.gov (United States)

    Caves, Katherine; Balestra, Simone

    2018-01-01

    The authors examined the short- and long-term effects of high school exit exams (HSEEs) on graduation rates and achievement using an interrupted time series approach. There is a positive overall effect of HSEE introduction for graduation rate trends, which is heterogeneous over time. HSEEs have a negative impact on graduation rates in the year of…

  16. Further Evidence of an Engagement-Achievement Paradox among U.S. High School Students

    Science.gov (United States)

    Shernoff, David J.; Schmidt, Jennifer A.

    2008-01-01

    Achievement, engagement, and students' quality of experience were compared by racial and ethnic group in a sample of students (N = 586) drawn from 13 high schools with diverse ethnic and socioeconomic student populations. Using the Experience Sampling Method (ESM), 3,529 samples of classroom experiences were analyzed along with self-reported…

  17. Moving on Up: Urban to Suburban Translocation Experiences of High-Achieving Black American Students

    Science.gov (United States)

    Yu, Xiaoqi; Seeberg, Vilma; Malone, Larissa

    2017-01-01

    Minority suburbanization has been a fast growing demographic shift in the United States during the first decade of the 21st century. This article examines the tapestry of the suburbanization experience of a group of high-achieving Black American students and their families as told by them. Departing from the all too common, deficit orientation…

  18. Filial Piety and Academic Motivation: High-Achieving Students in an International School in South Korea

    Science.gov (United States)

    Tam, Jonathan

    2016-01-01

    This study uses self-determination theory to explore the mechanisms of filial piety in the academic motivation of eight high-achieving secondary school seniors at an international school in South Korea, resulting in several findings. First, the students attributed their parents' values and expectations as a major source of the students'…

  19. Actively Closing the Gap? Social Class, Organized Activities, and Academic Achievement in High School

    Science.gov (United States)

    Morris, David S.

    2015-01-01

    Participation in Organized Activities (OA) is associated with positive behavioral and developmental outcomes in children. However, less is known about how particular aspects of participation affect the academic achievement of high school students from different social class positions. Using the Education Longitudinal Study of 2002, this study…

  20. Academic Identity Status, Goal Orientation, and Academic Achievement among High School Students

    Science.gov (United States)

    Hejazi, Elaheh; Lavasani, Masoud Gholamali; Amani, Habib; Was, Christopher A.

    2012-01-01

    The aim of the present study was to determine the relationship between academic identity status, goal orientations and academic achievement. 301 first year high school students completed the Academic Identity Measure and Goal Orientation Questionnaire. The average of 10 exam scores in the final semester was used as an index of academic…

  1. Brain Structure and Resting-State Functional Connectivity in University Professors with High Academic Achievement

    Science.gov (United States)

    Li, Weiwei; Yang, Wenjing; Li, Wenfu; Li, Yadan; Wei, Dongtao; Li, Huimin; Qiu, Jiang; Zhang, Qinglin

    2015-01-01

    Creative persons play an important role in technical innovation and social progress. There is little research on the neural correlates with researchers with high academic achievement. We used a combined structural (regional gray matter volume, rGMV) and functional (resting-state functional connectivity analysis, rsFC) approach to examine the…

  2. Rural Adolescents' Reading Motivation, Achievement and Behavior across Transition to High School

    Science.gov (United States)

    Cantrell, Susan Chambers; Rintamaa, Margaret; Anderman, Eric M.; Anderman, Lynley H.

    2018-01-01

    The authors examined 1,781 rural students' reading motivation and behavior across the transition from middle to high school. Using expectancy-value theory, they investigated how motivational variables predicted changes in reading behavior and achievement across the transition in terms of their expectancies, values, and out-of-school reading…

  3. Achievement, School Integration, and Self-Efficacy in Single-Sex and Coeducational Parochial High Schools

    Science.gov (United States)

    Micucci, Kara Hanson

    2014-01-01

    A structural model for prior achievement, school integration, and self-efficacy was developed using Tinto's theory of student attrition and Bandura's self-efficacy theory. The model was tested and revised using a sample of 1,452 males and females from single-sex and coeducational parochial high schools. Results indicated that the theoretically…

  4. Communication Satisfaction, Organizational Citizenship Behavior and the Relationship to Student Achievement in High Schools

    Science.gov (United States)

    Blanchard, Gayle A.

    2012-01-01

    This study used a correlational design that allowed the researcher to examine the relationship among communication satisfaction, organizational citizenship behaviors (OCB) and student achievement. High school teachers were surveyed from a convenience sample of 12 school districts in Arizona. Established instruments were used to survey teachers'…

  5. One-to-One Computing and Student Achievement in Ohio High Schools

    Science.gov (United States)

    Williams, Nancy L.; Larwin, Karen H.

    2016-01-01

    This study explores the impact of one-to-one computing on student achievement in Ohio high schools as measured by performance on the Ohio Graduation Test (OGT). The sample included 24 treatment schools that were individually paired with a similar control school. An interrupted time series methodology was deployed to examine OGT data over a period…

  6. Effects of Part-Time Work on School Achievement During High School

    Science.gov (United States)

    Singh, Kusum; Chang, Mido; Dika, Sandra

    2007-01-01

    The authors explored the effects of part-time work on school achievement during high school. To estimate the true effects of part-time work on school grades, the authors included family background, students' educational aspirations, and school engagement as controls. Although a substantial literature exists on the relationship of part-time work…

  7. Psychosocial aspects and management of evaluation in secondary high and low achievement

    Directory of Open Access Journals (Sweden)

    Alicia Rivera Morales

    2017-01-01

    Full Text Available This article describes a segment of a broader study of mixed cut occurs. In this space only part of the qualitative analysis is recovered around the psychosocial aspects that influence the management of the evaluation results from the application of semi-structured interviews and focus groups with 80 senior secondary schools with high and low achievement located in four states of Mexico: Sonora, Durango, Mexico City and Oaxaca. The findings are presented from categories they consider the meaning, beliefs and expectations about evaluation and how these aspects influence the actions of the directors of the schools studied. Polarized cases allow, in their contrasts, identify processes and factors that mark the differences or similarities between them. Thus it was found that school principals low achievement hope to change the attitude of teachers towards the assessment, expect supervisors to monitor teachers and external support (specialists that indicate how to evaluate them. Moreover, the idea that a school with high achievement is an organization that promotes the participation director, has high expectations of students and teachers, its management system and decision-making can achieve the objectives set, and reasserts Assessment proposes actions that seek continuous improvement.

  8. Modeling stability of growth between mathematics and science achievement during middle and high school.

    Science.gov (United States)

    Ma, Xin; Ma, Lingling

    2004-04-01

    In this study, the authors introduced a multivariate multilevel model to estimate the consistency among students and schools in the rates of growth between mathematics and science achievement during the entire middle and high school years with data from the Longitudinal Study of American Youth (LSAY). There was no evident consistency in the rates of growth between mathematics and science achievement among students, and this inconsistency was not much influenced by student characteristics and school characteristics. However, there was evident consistency in the average rates of growth between mathematics and science achievement among schools, and this consistency was influenced by student characteristics and school characteristics. Major school-level variables associated with parental involvement did not show any significant impacts on consistency among either students or schools. Results call for educational policies that promote collaboration between mathematics and science departments or teachers.

  9. Peace of Mind, Academic Motivation, and Academic Achievement in Filipino High School Students.

    Science.gov (United States)

    Datu, Jesus Alfonso D

    2017-04-09

    Recent literature has recognized the advantageous role of low-arousal positive affect such as feelings of peacefulness and internal harmony in collectivist cultures. However, limited research has explored the benefits of low-arousal affective states in the educational setting. The current study examined the link of peace of mind (PoM) to academic motivation (i.e., amotivation, controlled motivation, and autonomous motivation) and academic achievement among 525 Filipino high school students. Findings revealed that PoM was positively associated with academic achievement β = .16, p amotivation β = -.19, p < .05, and autonomous motivation was positively associated with academic achievement β = .52, p < .01. Furthermore, the results of bias-corrected bootstrap analyses at 95% confidence interval based on 5,000 bootstrapped resamples demonstrated that peace of mind had an indirect influence on academic achievement through the mediating effects of autonomous motivation. In terms of the effect sizes, the findings showed that PoM explained about 1% to 18% of the variance in academic achievement and motivation. The theoretical and practical implications of the results are elucidated.

  10. The role of chronotype, gender, test anxiety, and conscientiousness in academic achievement of high school students.

    Science.gov (United States)

    Rahafar, Arash; Maghsudloo, Mahdis; Farhangnia, Sajedeh; Vollmer, Christian; Randler, Christoph

    2016-01-01

    Previous findings have demonstrated that chronotype (morningness/intermediate/eveningness) is correlated with cognitive functions, that is, people show higher mental performance when they do a test at their preferred time of day. Empirical studies found a relationship between morningness and higher learning achievement at school and university. However, only a few of them controlled for other moderating and mediating variables. In this study, we included chronotype, gender, conscientiousness and test anxiety in a structural equation model (SEM) with grade point average (GPA) as academic achievement outcome. Participants were 158 high school students and results revealed that boys and girls differed in GPA and test anxiety significantly, with girls reporting better grades and higher test anxiety. Moreover, there was a positive correlation between conscientiousness and GPA (r = 0.17) and morningness (r = 0.29), respectively, and a negative correlation between conscientiousness and test anxiety (r = -0.22). The SEM demonstrated that gender was the strongest predictor of academic achievement. Lower test anxiety predicted higher GPA in girls but not in boys. Additionally, chronotype as moderator revealed a significant association between gender and GPA for evening types and intermediate types, while intermediate types showed a significant relationship between test anxiety and GPA. Our results suggest that gender is an essential predictor of academic achievement even stronger than low or absent test anxiety. Future studies are needed to explore how gender and chronotype act together in a longitudinal panel design and how chronotype is mediated by conscientiousness in the prediction of academic achievement.

  11. High fat diet promotes achievement of peak bone mass in young rats

    Energy Technology Data Exchange (ETDEWEB)

    Malvi, Parmanand; Piprode, Vikrant; Chaube, Balkrishna; Pote, Satish T. [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India); Mittal, Monika; Chattopadhyay, Naibedya [Division of Endocrinology and Center for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Jankipuram Extension, Sitapur Road, Lucknow 226 031 (India); Wani, Mohan R. [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India); Bhat, Manoj Kumar, E-mail: manojkbhat@nccs.res.in [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India)

    2014-12-05

    Highlights: • High fat diet helps in achieving peak bone mass at younger age. • Shifting from high fat to normal diet normalizes obese parameters. • Bone parameters are sustained even after withdrawal of high fat diet. - Abstract: The relationship between obesity and bone is complex. Epidemiological studies demonstrate positive as well as negative correlation between obesity and bone health. In the present study, we investigated the impact of high fat diet-induced obesity on peak bone mass. After 9 months of feeding young rats with high fat diet, we observed obesity phenotype in rats with increased body weight, fat mass, serum triglycerides and cholesterol. There were significant increases in serum total alkaline phosphatase, bone mineral density and bone mineral content. By micro-computed tomography (μ-CT), we observed a trend of better trabecular bones with respect to their microarchitecture and geometry. This indicated that high fat diet helps in achieving peak bone mass and microstructure at younger age. We subsequently shifted rats from high fat diet to normal diet for 6 months and evaluated bone/obesity parameters. It was observed that after shifting rats from high fat diet to normal diet, fat mass, serum triglycerides and cholesterol were significantly decreased. Interestingly, the gain in bone mineral density, bone mineral content and trabecular bone parameters by HFD was retained even after body weight and obesity were normalized. These results suggest that fat rich diet during growth could accelerate achievement of peak bone mass that is sustainable even after withdrawal of high fat diet.

  12. High fat diet promotes achievement of peak bone mass in young rats

    International Nuclear Information System (INIS)

    Malvi, Parmanand; Piprode, Vikrant; Chaube, Balkrishna; Pote, Satish T.; Mittal, Monika; Chattopadhyay, Naibedya; Wani, Mohan R.; Bhat, Manoj Kumar

    2014-01-01

    Highlights: • High fat diet helps in achieving peak bone mass at younger age. • Shifting from high fat to normal diet normalizes obese parameters. • Bone parameters are sustained even after withdrawal of high fat diet. - Abstract: The relationship between obesity and bone is complex. Epidemiological studies demonstrate positive as well as negative correlation between obesity and bone health. In the present study, we investigated the impact of high fat diet-induced obesity on peak bone mass. After 9 months of feeding young rats with high fat diet, we observed obesity phenotype in rats with increased body weight, fat mass, serum triglycerides and cholesterol. There were significant increases in serum total alkaline phosphatase, bone mineral density and bone mineral content. By micro-computed tomography (μ-CT), we observed a trend of better trabecular bones with respect to their microarchitecture and geometry. This indicated that high fat diet helps in achieving peak bone mass and microstructure at younger age. We subsequently shifted rats from high fat diet to normal diet for 6 months and evaluated bone/obesity parameters. It was observed that after shifting rats from high fat diet to normal diet, fat mass, serum triglycerides and cholesterol were significantly decreased. Interestingly, the gain in bone mineral density, bone mineral content and trabecular bone parameters by HFD was retained even after body weight and obesity were normalized. These results suggest that fat rich diet during growth could accelerate achievement of peak bone mass that is sustainable even after withdrawal of high fat diet

  13. Achievement Motivation of the High School Students: A Case Study among Different Communities of Goalpara District of Assam

    Science.gov (United States)

    Sarangi, C.

    2015-01-01

    Achievement motivation is a consistent striving force of an individual to achieve success to a certain standard of excellence in competing situation. In this study an attempt was made to study the effect of achievement motivation on the academic achievement of the high school students of tribal and non tribal communities in relation to their sex…

  14. The effectiveness of game and recreational activity to motivate high achievers and low achievers: Evaluation using fuzzy conjoint analysis

    Science.gov (United States)

    Sofian, Siti Siryani; Rambely, Azmin Sham

    2018-04-01

    Students' evaluation is important in order to determine the effectiveness of a learning program. A game and recreational activity (GaRA) is a problem-based learning (PBL) method that engages students in a learning process through games and activity. The effectiveness of GaRA can be determined from an application of fuzzy conjoint analysis (FCA) to diminish fuzziness in determining individual perceptions. This study involves a survey collected from 68 students participating in a Mathematics Discovery Camp organized by a UKM research group, named PRISMatik, from two different schools. The aim of this research was to determine the effectiveness of modules delivered to motivate students towards mathematics subject in the form of GaRA through different factors. There were six games conducted for the participants and their perceptions based on the evaluation of six criterias were measured. A seven-point Likert scale, which indicates seven linguistic terms, was used to collect students' preferences and perceptions on each module of GaRAs. Scores of perceptions were transformed into degrees of similarity using fuzzy set conjoint analysis. Results found that interest, effort and team work was the strongest values obtained from GaRA modules in this camp as participants indicated their strong agreement that these criteria fulfilled their preferences in most module. Participants also stated that almost all attributes fulfilled their preference in each module regardless their individual academic achievement. Thus the method demonstrated that modules delivered through PBL approach has effectively motivated students through six attributes introduced. The evaluation using FCA implicated the successfulness of a fuzzy approach to evaluate fuzziness obtained in the Likert-scale and has shown its ability in ranking the attributes from most preferred to least preferred.

  15. Achievements and opportunities from ESF Research Networking Programme: Natural molecular structures as drivers and tracers of terrestrial C fluxes, and COST Action 639: Greenhouse gas budget of soils under changing climate and land use

    Science.gov (United States)

    Boeckx, P.; Rasse, D.; Jandl, R.

    2009-04-01

    One of the activities of the European Science Foundation (ESF, www.esf.org) is developing European scale Research Networking Programmes (RNPs). RNPs lay the foundation for nationally funded research groups to address major scientific and research infrastructure issues, in order to advance the frontiers of existing science. MOLTER (www.esf.org/molter or www.molter.no) is such an RNP. MOLTER stands for "Natural molecular structures as drivers and tracers of terrestrial C fluxes" aims at stimulating the use of isotopic and organic chemistry to study carbon stabilization and biogeochemistry in terrestrial ecosystems and soils in particular. The understanding of the formation, stabilization and decomposition of complex organic compounds in the environment is currently being revolutionized by advanced techniques in identification, quantification, and origin tracing of functional groups and individual molecules. MOLTER focuses on five major research themes: - Molecular composition and turnover time of soil organic matter; - Plant molecular structures as drivers of C stabilisation in soils; - Fire transformations of plant and soil molecular structures - Molecular markers in soils; - Dissolved organic molecules in soils: origin, functionality and transport. These research themes are covered via the following activities: - Organisation of international conferences; - Organisation of specific topical workshops; - Organisation of summer schools for PhD students; - Short- and long-term exchange grants for scientists. MOLTER is supported by research funding or performing agencies from Austria, Belgium, France, Germany, the Netherlands, Norway, Romania, Spain, Sweden, Switzerland and the United Kingdom. The ESF is also the implementing agency of COST (European Cooperation in Science and Technology, www.cost.esf.org), one of the longest-running European instruments supporting cooperation among scientists and researchers across Europe. COST Action 639 "Greenhouse gas budget of

  16. The impact of including children with intellectual disability in general education classrooms on the academic achievement of their low-, average-, and high-achieving peers.

    Science.gov (United States)

    Sermier Dessemontet, Rachel; Bless, Gérard

    2013-03-01

    This study aimed at assessing the impact of including children with intellectual disability (ID) in general education classrooms with support on the academic achievement of their low-, average-, and high-achieving peers without disability. A quasi-experimental study was conducted with an experimental group of 202 pupils from classrooms with an included child with mild or moderate ID, and a control group of 202 pupils from classrooms with no included children with special educational needs (matched pairs sample). The progress of these 2 groups in their academic achievement was compared over a period of 1 school year. No significant difference was found in the progress of the low-, average-, or high-achieving pupils from classrooms with or without inclusion. The results suggest that including children with ID in primary general education classrooms with support does not have a negative impact on the progress of pupils without disability.

  17. From Great to Good: Principals' Sensemaking of Student Performance Decline in Formerly High Achieving High Poverty Schools

    Science.gov (United States)

    Darbonne, Deborah

    2016-01-01

    School level leadership is second only to effective instruction as essential to high student achievement (Leithwood, Louis, Anderson & Wahlstrom, 2004). Although factors such as socioeconomic levels and parental involvement contribute to the academic success of students, school leadership outweighs the impact of those factors. In the era of…

  18. Toward achieving flexible and high sensitivity hexagonal boron nitride neutron detectors

    Science.gov (United States)

    Maity, A.; Grenadier, S. J.; Li, J.; Lin, J. Y.; Jiang, H. X.

    2017-07-01

    Hexagonal boron nitride (h-BN) detectors have demonstrated the highest thermal neutron detection efficiency to date among solid-state neutron detectors at about 51%. We report here the realization of h-BN neutron detectors possessing one order of magnitude enhancement in the detection area but maintaining an equal level of detection efficiency of previous achievement. These 3 mm × 3 mm detectors were fabricated from 50 μm thick freestanding and flexible 10B enriched h-BN (h-10BN) films, grown by metal organic chemical vapor deposition followed by mechanical separation from sapphire substrates. Mobility-lifetime results suggested that holes are the majority carriers in unintentionally doped h-BN. The detectors were tested under thermal neutron irradiation from californium-252 (252Cf) moderated by a high density polyethylene moderator. A thermal neutron detection efficiency of ˜53% was achieved at a bias voltage of 200 V. Conforming to traditional solid-state detectors, the realization of h-BN epilayers with enhanced electrical transport properties is the key to enable scaling up the device sizes. More specifically, the present results revealed that achieving an electrical resistivity of greater than 1014 Ωṡcm and a leakage current density of below 3 × 10-10 A/cm2 is needed to fabricate large area h-BN detectors and provided guidance for achieving high sensitivity solid state neutron detectors based on h-BN.

  19. The Exploration of the Associations between Locus of Control and High School Students’ Language Achievement

    Directory of Open Access Journals (Sweden)

    Abbas Eslami-Rasekh

    2012-07-01

    Full Text Available The purpose of the study is to determine the relationships between locus of control (LOC orientation and high school students’ language achievement. The popular categorization of internals and externals was taken into account. The participants of this study were 121 high school students in the second, third and pre-university grades in two public high schools of Isfahan, Iran. One of the instruments used in the study was an adopted version of Julian Rotters’ locus of control (1966 which identified internal and external orientations. The participants’ English scores were regarded as the measure of their achievement. Besides, a questionnaire consisting of 29 items was administered to all 121 students. Responses were put into one way and two-way ANOVA, the regression analysis, the independent t-test, chi-square and linear regression analysis to compare the means of two sets of scores. The findings of this study show a significant relationship between locus control and achievement of high school students. The findings can be used by EFL teachers and syllabus designers.

  20. Utilizing leadership to achieve high reliability in the delivery of perinatal care

    Directory of Open Access Journals (Sweden)

    Parrotta C

    2012-11-01

    Full Text Available Carmen Parrotta,1 William Riley,1 Les Meredith21School of Public Health, University of Minnesota, Minneapolis, MN, 2Premier Insurance Management Services Inc, Charlotte, NC, USAAbstract: Highly reliable care requires standardization of clinical practices and is a prerequisite for patient safety. However, standardization in complex hospital settings is extremely difficult to attain and health care leaders are challenged to create care delivery processes that ensure patient safety. Moreover, once high reliability is achieved in a hospital unit, it must be maintained to avoid process deterioration. This case study examines an intervention to implement care bundles (a collection of evidence-based practices in four hospitals to achieve standardized care in perinatal units. The results show different patterns in the rate and magnitude of change within the hospitals to achieve high reliability. The study is part of a larger nationwide study of 16 hospitals to improve perinatal safety. Based on the findings, we discuss the role of leadership for implementing and sustaining high reliability to ensure freedom from unintended injury.Keywords: care bundles, evidence-based practice, standardized care, process improvement

  1. When high achievers and low achievers work in the same group: the roles of group heterogeneity and processes in project-based learning.

    Science.gov (United States)

    Cheng, Rebecca Wing-yi; Lam, Shui-fong; Chan, Joanne Chung-yan

    2008-06-01

    There has been an ongoing debate about the inconsistent effects of heterogeneous ability grouping on students in small group work such as project-based learning. The present research investigated the roles of group heterogeneity and processes in project-based learning. At the student level, we examined the interaction effect between students' within-group achievement and group processes on their self- and collective efficacy. At the group level, we examined how group heterogeneity was associated with the average self- and collective efficacy reported by the groups. The participants were 1,921 Hong Kong secondary students in 367 project-based learning groups. Student achievement was determined by school examination marks. Group processes, self-efficacy and collective efficacy were measured by a student-report questionnaire. Hierarchical linear modelling was used to analyse the nested data. When individual students in each group were taken as the unit of analysis, results indicated an interaction effect of group processes and students' within-group achievement on the discrepancy between collective- and self-efficacy. When compared with low achievers, high achievers reported lower collective efficacy than self-efficacy when group processes were of low quality. However, both low and high achievers reported higher collective efficacy than self-efficacy when group processes were of high quality. With 367 groups taken as the unit of analysis, the results showed that group heterogeneity, group gender composition and group size were not related to the discrepancy between collective- and self-efficacy reported by the students. Group heterogeneity was not a determinant factor in students' learning efficacy. Instead, the quality of group processes played a pivotal role because both high and low achievers were able to benefit when group processes were of high quality.

  2. Means of achieving high load factors at Olkiluoto 1 and 2

    International Nuclear Information System (INIS)

    Patrakka, E.

    2001-01-01

    Teollisuuden Voima Oy operates two BWR units Olkiluoto 1 and 2 that have achieved load factors typically higher than 90%. The operating experiences gained in the 1990s is summarised and the factors contributing to the high capacity factors are addressed. These include the general objectives for operation and maintenance, plant modernisation programme, maintenance principles, and outage policy and experiences. Finally, the international evaluations performed at Olkiluoto are mentioned. (author)

  3. Terrestrial studies

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    Tritium in the organic fraction of soil, separated as water by high temperature combustion, was 5 to 50 times higher in activity than water that was freeze-dried from the same samples. The 50-year dose commitment from ingestion of crops is not influenced significantly by the plutonium in the SRP environment. This plutonium is a result of more than 20 years of operating chemical separations facilities. Techniques were developed to detect as little as 0.02 pCi/m 2 of iodine-129 and 0.2 pg of technetium-99 in soil to evaluate environmental effects. A sensitive three-stage mass spectrometer was completed for use in environmental studies of transuranium elements. Results of monitoring particle size distribution of entrapped particles containing Pu-238, and Pu-239,240 are reported

  4. Global Drainage Patterns to Modern Terrestrial Sedimentary Basins and its Influence on Large River Systems

    Science.gov (United States)

    Nyberg, B.; Helland-Hansen, W.

    2017-12-01

    Long-term preservation of alluvial sediments is dependent on the hydrological processes that deposit sediments solely within an area that has available accomodation space and net subsidence know as a sedimentary basin. An understanding of the river processes contributing to terrestrial sedimentary basins is essential to fundamentally constrain and quantify controls on the modern terrestrial sink. Furthermore, the terrestrial source to sink controls place constraints on the entire coastal, shelf and deep marine sediment routing systems. In addition, the geographical importance of modern terrestrial sedimentary basins for agriculture and human settlements has resulted in significant upstream anthropogenic catchment modification for irrigation and energy needs. Yet to our knowledge, a global catchment model depicting the drainage patterns to modern terrestrial sedimentary basins has previously not been established that may be used to address these challenging issues. Here we present a new database of 180,737 global catchments that show the surface drainage patterns to modern terrestrial sedimentary basins. This is achieved by using high resolution river networks derived from digital elevation models in relation to newly acquired maps on global modern sedimentary basins to identify terrestrial sinks. The results show that active tectonic regimes are typically characterized by larger terrestrial sedimentary basins, numerous smaller source catchments and a high source to sink relief ratio. To the contrary passive margins drain catchments to smaller terrestrial sedimentary basins, are composed of fewer source catchments that are relatively larger and a lower source to sink relief ratio. The different geomorphological characteristics of source catchments by tectonic setting influence the spatial and temporal patterns of fluvial architecture within sedimentary basins and the anthropogenic methods of exploiting those rivers. The new digital database resource is aimed to help

  5. Achieving high baryon densities in the fragmentation regions in heavy ion collisions at top RHIC energy

    International Nuclear Information System (INIS)

    Li, Ming; Kapusta, Joseph I.

    2017-01-01

    Heavy ion collisions at extremely high energy, such as the top energy at RHIC, exhibit the property of transparency where there is a clear separation between the almost net-baryon-free central rapidity region and the net-baryon-rich fragmentation region. We calculate the net-baryon rapidity loss and the nuclear excitation energy using the energy-momentum tensor obtained from the McLerran-Venugopalan model. Nuclear compression during the collision is further estimated using a simple space-time picture. The results show that extremely high baryon densities, about twenty times larger than the normal nuclear density, can be achieved in the fragmentation regions. (paper)

  6. Achieving Hydrogen Storage Goals through High-Strength Fiber Glass - Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hong [PPG Industries, Inc., Cheswick, PA (United States); Johnson, Kenneth I. [PPG Industries, Inc., Cheswick, PA (United States); Newhouse, Norman L. [PPG Industries, Inc., Cheswick, PA (United States)

    2017-06-05

    Led by PPG and partnered with Hexagon Lincoln and Pacific Northwest National Laboratory (PNNL), the team recently carried out a project “Achieving Hydrogen Storage Goals through High-Strength Fiber Glass”. The project was funded by DOE’s Fuel Cell Technologies office within the Office of Energy Efficiency and Renewable Energy, starting on September 1, 2014 as a two-year project to assess technical and commercial feasibilities of manufacturing low-cost, high-strength glass fibers to replace T700 carbon fibers with a goal of reducing the composite total cost by 50% of the existing, commercial 700 bar hydrogen storage tanks used in personal vehicles.

  7. Heterogeneity in High Math Achievement across Schools: Evidence from the American Mathematics Competitions. NBER Working Paper No. 18277

    Science.gov (United States)

    Ellison, Glenn; Swanson, Ashley

    2012-01-01

    This paper explores differences in the frequency with which students from different schools reach high levels of math achievement. Data from the American Mathematics Competitions is used to produce counts of high-scoring students from more than two thousand public, coeducational, non-magnet, non-charter U.S. high schools. High-achieving students…

  8. The effects of modeling instruction on high school physics academic achievement

    Science.gov (United States)

    Wright, Tiffanie L.

    The purpose of this study was to explore whether Modeling Instruction, compared to traditional lecturing, is an effective instructional method to promote academic achievement in selected high school physics classes at a rural middle Tennessee high school. This study used an ex post facto , quasi-experimental research methodology. The independent variables in this study were the instructional methods of teaching. The treatment variable was Modeling Instruction and the control variable was traditional lecture instruction. The Treatment Group consisted of participants in Physical World Concepts who received Modeling Instruction. The Control Group consisted of participants in Physical Science who received traditional lecture instruction. The dependent variable was gains scores on the Force Concepts Inventory (FCI). The participants for this study were 133 students each in both the Treatment and Control Groups (n = 266), who attended a public, high school in rural middle Tennessee. The participants were administered the Force Concepts Inventory (FCI) prior to being taught the mechanics of physics. The FCI data were entered into the computer-based Statistical Package for the Social Science (SPSS). Two independent samples t-tests were conducted to answer the research questions. There was a statistically significant difference between the treatment and control groups concerning the instructional method. Modeling Instructional methods were found to be effective in increasing the academic achievement of students in high school physics. There was no statistically significant difference between FCI gains scores for gender. Gender was found to have no effect on the academic achievement of students in high school physics classes. However, even though there was not a statistically significant difference, female students' gains scores were higher than male students' gains scores when Modeling Instructional methods of teaching were used. Based on these findings, it is recommended

  9. Moving to higher ground: Closing the high school science achievement gap

    Science.gov (United States)

    Mebane, Joyce Graham

    The purpose of this study was to examine the perceptions of West High School constituents (students, parents, teachers, administrators, and guidance counselors) about the readiness and interest of African American students at West High School to take Advanced Placement (AP) and International Baccalaureate (IB) science courses as a strategy for closing the achievement gap. This case study utilized individual interviews and questionnaires for data collection. The participants were selected biology students and their parents, teachers, administrators, and guidance counselors at West High School. The results of the study indicated that just over half the students and teachers, most parents, and all guidance counselors thought African American students were prepared to take AP science courses. Only one of the three administrators thought the students were prepared to take AP science courses. Between one-half and two-thirds of the students, parents, teachers, and administrators thought students were interested in taking an AP science course. Only two of the guidance counselors thought there was interest among the African American students in taking AP science courses. The general consensus among the constituents about the readiness and interest of African American students at West High School to take IB science courses was that it is too early in the process to really make definitive statements. West is a prospective IB school and the program is new and not yet in place. Educators at the West High School community must find reasons to expect each student to succeed. Lower expectations often translate into lower academic demands and less rigor in courses. Lower academic demands and less rigor in courses translate into less than adequate performance by students. When teachers and administrators maintain high expectations, they encourage students to aim high rather than slide by with mediocre effort (Lumsden, 1997). As a result of the study, the following suggestions should

  10. Hmong Parental Involvement and Support: A Comparison Between Families of High and Low Achieving High School Seniors

    Directory of Open Access Journals (Sweden)

    Katherine Green

    2009-01-01

    Full Text Available The Hmong are some of the newest refugees who have settled in the United States with population estimates around 300,000. Unfortunately research has shown many Hmong children are not as successful in their education as their peers. Parental involvement in education has consistently been shown to impact academic success and attendance in higher education programs. Little is known about Hmong parental involvement in their children’s education process. Therefore, this study was done to compare and contrast the general family characteristics, parenting methods, parental involvement philosophies, parental involvement experiences, and parental education expectations in Hmong families of high school seniors classified as either high academic achievers or low achievers. Students were classified into either higher or lower academic achievement groups based on their high school cumulative GPA. Five students were randomly selected for each group and a qualitative research interview method was used to interview the students and both of their parents (n=30. The findings showed the parents of the higher academic achieving students were younger, had higher levels of education, and had better relationships and trust with the students. Parents from both groups did not have any written rules for their children to follow at home, they mainly became involved in their children’s education during the elementary and middle school years, and they did not have any specific preference of an educational level, career, or school for their children after high school. Recommendations for ways Hmong families can be encouraged to participate more in education are made.

  11. Advances in high-resolution synchrotron micro-XANES for constraining the redox evolution of terrestrial and extraterrestrial magma

    Science.gov (United States)

    Lanzirotti, A.; Sutton, S. R.; Dyar, M. D.; McCanta, M. C.; Head, E.

    2017-12-01

    Quantifying the redox evolution of geological materials is of fundamental importance for understanding the evolution of the Earth and terrestrial planets. Microfocused, synchrotron X-ray Absorption Spectroscopy (XAS) provides direct, in-situ analyses of the valence state for elements that can be used as proxies for oxygen fugacity (Fe, V, Cr, Ti, S, Eu, and Ce). Such proxies span the entire fO2 range of solar system evolution, covering at least 16 log units. Recent technical improvements at the Advanced Photon Source 13-ID-E microspectroscopy beamline have improved the energy, spatial resolution and detection sensitivity for XAS. The application of multiple valence state oxybarometers to individual mineral grains is valuable as demonstrated in a study of Ti, V and Cr valence in olivine and pyroxene of the ungrouped achondrite NWA 7325 [1], results which yielded a very reduced fO2 estimate of IW-3 and suggested a likely origin of NWA 7325 in a parent body with similar redox conditions to the ureilite parent body. Simultaneously, we have made advances using multivariate prediction models to more precisely measure ever-smaller variations in elemental valence [2]. Applied to V XAS spectra in glasses, we have developed an MVA calibration model that directly relates the measured spectra to predicted fO2, improving the precision in calculating fO2 with more robust error analysis. These machine learning based algorithms also allow for XAS to be collected in an imaging modality to spatially map elemental redox states within samples. For example for imaging changes in Fe oxidation state in natural lunar picritic glasses [3] that may be related to magmatic degassing. This presentation highlights recent examples of this research at 13-ID-E, including application of Fe, S and V valence state oxybarometers in the analysis of terrestrial volcanic glasses and melt inclusions for looking at long term evolution of oxygen fugacity of magmas. [1] Sutton S. et al. (2017) GCA, 211, 115

  12. Challenges to achievement of metal sustainability in our high-tech society.

    Science.gov (United States)

    Izatt, Reed M; Izatt, Steven R; Bruening, Ronald L; Izatt, Neil E; Moyer, Bruce A

    2014-04-21

    Achievement of sustainability in metal life cycles from mining of virgin ore to consumer and industrial devices to end-of-life products requires greatly increased recycling rates and improved processing of metals using conventional and green chemistry technologies. Electronic and other high-tech products containing precious, toxic, and specialty metals usually have short lifetimes and low recycling rates. Products containing these metals generally are incinerated, discarded as waste in landfills, or dismantled in informal recycling using crude and environmentally irresponsible procedures. Low recycling rates of metals coupled with increasing demand for high-tech products containing them necessitate increased mining with attendant environmental, health, energy, water, and carbon-footprint consequences. In this tutorial review, challenges to achieving metal sustainability, including projected use of urban mining, in present high-tech society are presented; health, environmental, and economic incentives for various government, industry, and public stakeholders to improve metal sustainability are discussed; a case for technical improvements, including use of molecular recognition, in selective metal separation technology, especially for metal recovery from dilute feed stocks is given; and global consequences of continuing on the present path are examined.

  13. Distortion or Clarification: Defining Highly Qualified Teachers and the Relationship between Certification and Achievement

    Directory of Open Access Journals (Sweden)

    Jacob M Marszalek

    2010-11-01

    Full Text Available Recent studies of the relationship between teacher preparation pathways and student achievement have resulted in similar statistics but contradictory conclusions. These studies as a group have several limits: they sometimes focus on student-level indicators when many policy decisions are made with indicators at the school-level or above, are limited to specific urban locations or grade levels, or neglect the potential influence of building type, as defined as the grade-levels serviced. Using statewide data from the 2004-2005 school year, we examined the relationships between school-level indicators of student achievement on nationally-normed tests and proportions of alternatively certified teachers, while controlling for building type and other relevant covariates. Our findings indicate that the relationship between teacher preparation and student achievement at the school level depends on whether the building mixes multiple grade levels (e.g., elementary and middle. The implications of Missouri's policy change for research and school improvement are discussed with respect to the current high-stakes testing environment.

     

  14. Comparative Analysis of Rote Learning on High and Low Achievers in Graduate and Undergraduate Programs

    Directory of Open Access Journals (Sweden)

    Ambreen Ahmed

    2017-06-01

    Full Text Available A survey was conducted to study the preferred learning strategies; that is, surface learning or deep learning of undergraduate and graduate male and female students and the impact of the preferred strategy on their academic performance. Both learning strategies help university students to get good scores in their examinations to meet the demands of industry in workforce. Quantitative research method was used to determine the impact of learning strategy on academic achievements. The R-SPQ2F questionnaire was sent to 103 students through Google forms and hard copies through snowball sampling technique. The results show that rote learning and academic performance are inversely related to each other. In high achievers, deep learning is significant as compared to low achievers. Furthermore, comparative analysis of learning styles on males and females showed that both preferred deep learning strategy equally. Learning strategy is not related to education level of students because there is no difference among preferred learning strategies of graduate and undergraduate students.

  15. Race and Academic Achievement in Racially Diverse High Schools: Opportunity and Stratification.

    Science.gov (United States)

    Muller, Chandra; Riegle-Crumb, Catherine; Schiller, Kathryn S; Wilkinson, Lindsey; Frank, Kenneth A

    2010-04-01

    BACKGROUND/CONTEXT: Brown v Board of Education fundamentally changed our nation's schools, yet we know surprisingly little about how and whether they provide equality of educational opportunity. Although substantial evidence suggests that African American and Latino students who attend these schools face fewer learning opportunities than their White counterparts, until now, it has been impossible to examine this using a representative sample because of lack of data. PURPOSE/OBJECTIVE/RESEARCH QUESTION/FOCUS OF STUDY: This study uses newly available data to investigate whether racially diverse high schools offer equality of educational opportunity to students from different racial and ethnic groups. This is examined by measuring the relative representation of minority students in advanced math classes at the beginning of high school and estimating whether and how this opportunity structure limits the level of achievement attained by African American and Latino students by the end of high school. SETTING: This study uses data from the Adolescent Health and Academic Achievement Study (AHAA) and its partner study, the National Longitudinal Study of Adolescent Health (Add Health), a stratified, nationally representative study of students in U.S. high schools first surveyed in 1994-1995. POPULATION/PARTICIPANTS/SUBJECTS: Two samples of racially diverse high schools were used in the analysis: one with African Americans, Whites, and Asians (26 schools with 3,149 students), and the other with Latinos, Whites, and Asians (22 schools with 2,775 students). RESEARCH DESIGN: Quantitative analyses first assess how high schools vary in the extent to which minority students are underrepresented in advanced sophomore math classes. Hierarchical multilevel modeling is then used to estimate whether racial-ethnic differences in representation in advanced math have an impact on African American and Latino students' achievement by the end of high school, relative to the Whites and Asians

  16. Cognitive abilities and motivational processes in high school students' science achievement and engagement

    Science.gov (United States)

    Lau, Shun

    The dissertation presents two analytic approaches, a variable-centered and person-centered approach, to investigating holistic patterns of the cognitive, motivational, and affective correlates of science achievement and engagement in a sample of 491 10th and 11th grade high-school students. Building on Snow's (1989) idea of two pathways to achievement outcomes, Study 1 adopted a variable-centered approach to examining how cognitive and motivational factors associated with the performance and commitment pathways, respectively, contributed to the prediction of achievement outcomes in science. Results of hierarchical regression analyses showed that (a) students' cognitive abilities were the strongest predictors of their performance in science as measured by standardized test scores; (b) motivational processes enhanced the predictive validity for science test scores and grades beyond the variance accounted for by ability and demography; (c) motivational processes were the strongest predictors of students' commitment to science in the form of situational engagement and anticipated choices of science-related college majors and careers; and (d) competence beliefs served as a point of contact between the performance and commitment pathways. These results are consistent with Snow's (1989) conjecture that both performance and commitment pathway-related factors are necessary for understanding the full range of person-level inputs to achievement outcomes. Study 2 adopted a person-centered approach to examining holistic organizations of psychological factors within individuals and their relations to science achievement and engagement. Four types of students characterized by unique configurations of cognitive, motivational, and affective attributes were identified in both the male and female subsamples using inverse factor analysis. Type membership was found to distinguish students in various indicators of science achievement and engagement. Two of the four types were also found

  17. Achieving high mobility ZnO : Al at very high growth rates by dc filtered cathodic arc deposition

    International Nuclear Information System (INIS)

    Mendelsberg, R J; Lim, S H N; Wallig, J; Anders, A; Zhu, Y K; Milliron, D J

    2011-01-01

    Achieving a high growth rate is paramount for making large-area transparent conducting oxide coatings at a low cost. Unfortunately, the quality of thin films grown by most techniques degrades as the growth rate increases. Filtered dc cathodic arc is a lesser known technique which produces a stream of highly ionized plasma, in stark contrast to the neutral atoms produced by standard sputter sources. Ions bring a large amount of potential energy to the growing surface which is in the form of heat, not momentum. By minimizing the distance from cathode to substrate, the high ion flux gives a very high effective growth temperature near the film surface without causing damage from bombardment. The high surface temperature is a direct consequence of the high growth rate and allows for high-quality crystal growth. Using this technique, 500-1300 nm thick and highly transparent ZnO : Al films were grown on glass at rates exceeding 250 nm min -1 while maintaining resistivity below 5 x 10 -4 Ω cm with electron mobility as high as 60 cm 2 V -1 s -1 . (fast track communication)

  18. High Titer and Yields Achieved with Novel, Low-Severity Pretreatment Strategy

    Energy Technology Data Exchange (ETDEWEB)

    2016-03-01

    NREL researchers obtained high concentration sugar syrups in enzymatic hydrolysis that are fermentable to ethanol and other advanced biofuels and intermediate products at high yields. The novel DMR process is simpler and bypasses all severe pretreatment methods, thus reducing the environmental impact. The results are unprecedented. Researchers achieved a high concentration of sugars (230g/L of monomeric sugar and 270 g/L total sugar) and this low toxicity, highly fermentable syrup yielded 86 g/L ethanol (> 90 percent conversion). In addition, the lignin streams from this process can readily be converted to jet or renewable diesel blendstocks through a hydrodeoxygenation step. The NREL-developed, low severity DMR process may potentially replace higher severity chemical pretreatments and associated expensive reactors constructed of exotic alloys with a simpler process, using commercial-scale equipment commonly associated with the pulp and paper industry, to produce high concentration, low toxicity sugar streams and highly reactive lignin streams from non-food renewable biomass for biological and catalytic upgrading to advanced biofuels and chemicals. The simpler DMR process with black liquor recycling could reduce environmental and life-cycle impacts, and repurpose shuttered pulp and paper mills to help revitalize rural economies.

  19. High-Resolution Assimilation of GRACE Terrestrial Water Storage Observations to Represent Local-Scale Water Table Depths

    Science.gov (United States)

    Stampoulis, D.; Reager, J. T., II; David, C. H.; Famiglietti, J. S.; Andreadis, K.

    2017-12-01

    Despite the numerous advances in hydrologic modeling and improvements in Land Surface Models, an accurate representation of the water table depth (WTD) still does not exist. Data assimilation of observations of the joint NASA and DLR mission, Gravity Recovery and Climate Experiment (GRACE) leads to statistically significant improvements in the accuracy of hydrologic models, ultimately resulting in more reliable estimates of water storage. However, the usually shallow groundwater compartment of the models presents a problem with GRACE assimilation techniques, as these satellite observations account for much deeper aquifers. To improve the accuracy of groundwater estimates and allow the representation of the WTD at fine spatial scales we implemented a novel approach that enables a large-scale data integration system to assimilate GRACE data. This was achieved by augmenting the Variable Infiltration Capacity (VIC) hydrologic model, which is the core component of the Regional Hydrologic Extremes Assessment System (RHEAS), a high-resolution modeling framework developed at the Jet Propulsion Laboratory (JPL) for hydrologic modeling and data assimilation. The model has insufficient subsurface characterization and therefore, to reproduce groundwater variability not only in shallow depths but also in deep aquifers, as well as to allow GRACE assimilation, a fourth soil layer of varying depth ( 1000 meters) was added in VIC as the bottom layer. To initialize a water table in the model we used gridded global WTD data at 1 km resolution which were spatially aggregated to match the model's resolution. Simulations were then performed to test the augmented model's ability to capture seasonal and inter-annual trends of groundwater. The 4-layer version of VIC was run with and without assimilating GRACE Total Water Storage anomalies (TWSA) over the Central Valley in California. This is the first-ever assimilation of GRACE TWSA for the determination of realistic water table depths, at

  20. Achieving Ohmic Contact for High-quality MoS2 Devices on Hexagonal Boron Nitride

    Science.gov (United States)

    Cui, Xu

    MoS2, among many other transition metal dichalcogenides (TMDCs), holds great promise for future applications in nano-electronics, opto-electronics and mechanical devices due to its ultra-thin nature, flexibility, sizable band-gap, and unique spin-valley coupled physics. However, there are two main challenges that hinder careful study of this material. Firstly, it is hard to achieve Ohmic contacts to mono-layer MoS2, particularly at low temperatures (T) and low carrier densities. Secondly, materials' low quality and impurities introduced during the fabrication significantly limit the electron mobility of mono- and few-layer MoS2 to be substantially below theoretically predicted limits, which has hampered efforts to observe its novel quantum transport behaviours. Traditional low work function metals doesn't necessary provide good electron injection to thin MoS2 due to metal oxidation, Fermi level pinning, etc. To address the first challenge, we tried multiple contact schemes and found that mono-layer hexagonal boron nitride (h-BN) and cobalt (Co) provide robust Ohmic contact. The mono-layer spacer serves two advantageous purposes: it strongly interacts with the transition metal, reducing its work function by over 1 eV; and breaks the metal-TMDCs interaction to eliminate the interfacial states that cause Fermi level pinning. We measure a flat-band Schottky barrier of 16 meV, which makes thin tunnel barriers upon doping the channels, and thus achieve low-T contact resistance of 3 kohm.um at a carrier density of 5.3x10. 12/cm. 2. Similar to graphene, eliminating all potential sources of disorder and scattering is the key to achieving high performance in MoS2 devices. We developed a van der Waals heterostructure device platform where MoS2 layers are fully encapsulated within h-BN and electrically contacted in a multi-terminal geometry using gate-tunable graphene electrodes. The h-BN-encapsulation provides excellent protection from environmental factors, resulting in

  1. Important learning factors in high- and low-achieving students in undergraduate biomechanics.

    Science.gov (United States)

    Hsieh, ChengTu; Knudson, Duane

    2017-07-21

    The purpose of the present study was to document crucial factors associated with students' learning of biomechanical concepts, particularly between high- and-low achieving students. Students (N = 113) from three introductory biomechanics classes at two public universities volunteered for the study. Two measures of students' learning were obtained, final course grade and improvement on the Biomechanics Concept Inventory version 3 administered before and after the course. Participants also completed a 15-item questionnaire documenting student learning characteristics, effort, and confidence. Partial correlations controlling for all other variables in the study, confirmed previous studies that students' grade point average (p biomechanics, (p biomechanics concepts. Students' confidence when encountering difficult biomechanics concepts was also significantly (p biomechanics and confidence in solving relevant professional problems in order to improve learning for both low- and high-ability students.

  2. What Makes a Good Program? A Case Study of a School Admitting High Academic Achievers

    Directory of Open Access Journals (Sweden)

    Ching Man Lam

    2008-01-01

    Full Text Available This paper reports the results of a qualitative study that explored the administration and implementation of the Tier 1 Program (Secondary 1 Curriculum of the Project P.A.T.H.S. The case study method was used to explore perceptions of the teachers and the project coordinator of program effectiveness, and to identify various factors for program success. A school admitting high academic achievers was selected, and site visits, as well as individual and focus group interviews, were conducted with the program coordinator, social worker, and course teachers. The results suggested that clear vision and program goals, high quality of curriculum, helpful leadership, positive teacher attitude, and strong administrative support are factors for program success. Analyzing the data enables the researchers to understand the characteristics of a successful program as well as the interplay among factors for producing success.

  3. Structure of the terrestrial planets

    International Nuclear Information System (INIS)

    Lyttleton, R.A.

    1977-01-01

    Recent reviews (cf. Runcorn, 1968; or Cook, 1972, 1975) on the structure of the planets omit reference to the phase-change hypothesis for the nature of the terrestrial core, despite that numerous prior predictions of the theory based on this hypothesis have subsequently been borne out as correct. These reviews also ignore the existence of theoretical calculations of the internal structure of Venus which can be computed with high accuracy by use of the terrestrial seismic data. Several examples of numerous mistakes committed in these reviews are pointed out. (Auth.)

  4. ANALYZING THE MATHEMATICAL DISPOSITION AND ITS CORRELATION WITH MATHEMATICS ACHIEVEMENT OF ABSTRACT SENIOR HIGH SCHOOL STUDENTS

    Directory of Open Access Journals (Sweden)

    Louise M. Saija

    2012-09-01

    Full Text Available Salah satu standar yang diberikan oleh National Council of Teachers of Mathematics (NCTM adalah disposisi matematik. Disposisi  bukan sekedar merujuk pada sikap tetapi suatu kecenderungan untuk berpikir dan bersikap dalam cara yang positif. Penelitian ini bertujuan untuk menganalisa disposisi matematik dan hubungannya dengan hasil belajar matematika siswa-siswa sekolah menengah atas (SMA. Sampel pada penelitian ini adalah 149 siswa SMA di Bandung. Analisa statistik didasarkan pada korelasi peringkat Spearman dan uji-t. Ditemukan bahwa secara rata-rata,  disposisi matematik dari siswa-siswa SMA dikategorikan rendah. Selanjutnya, terdapat korelasi positif dan signifikan antara disposisi matematik dan hasil belajar matematika siswa-siswa SMA, walaupun nilai koefisien korelasinya tidak tinggi. Suatu observasi juga dilakukan untuk menganalisa hubungan ini, dan didapati bahwa walaupun beberapa siswa memiliki disposisi matematik yang baik, kadang kala mereka tidak dapat menyelesaikan ujian dengan baik, karena padatnya kurikulum, dan juga aktifitas sosial mereka, yang membuat hasil belajar matematika mereka lebih rendah. Temuan lainnya adalah bahwa siswa-siswa SMA memerlukan guru-guru matematika dengan lebih banyak strategi mengajar  agar mereka dapat memiliki disposisi matematik yang lebih baik.   Kata Kunci: Disposisi Matematik, Hasil Belajar Matematika       One of the evaluation standards given by the National Council of Teachers of Mathematics (NCTM was mathematical disposition. Disposition refers not simply to attitudes but to a tendency to think and to act in positive ways. This study aimed to analyze the mathematical disposition and its correlation with mathematics achievement of senior high school (SMA students. A total of 149 SMA students in Bandung were procured as samples. Statistical analysis was based on the Spearman rank correlation and on the t-test. The findings showed that at average, the mathematical disposition of the SMA

  5. Tuning charge balance in PHOLEDs with ambipolar host materials to achieve high efficiency

    International Nuclear Information System (INIS)

    Padmaperuma, Asanga B.; Koech, Phillip K.; Cosimbescu, Lelia; Polikarpov, Evgueni; Swensen, James S.; Chopra, Neetu; So, Franky; Sapochak, Linda S.; Gaspar, Daniel J.

    2009-01-01

    The efficiency and stability of blue organic light emitting devices (OLEDs) continue to be a primary roadblock to developing organic solid state white lighting. For OLEDs to meet the high power conversion efficiency goal, they will require both close to 100% internal quantum efficiency and low operating voltage in a white light emitting device. It is generally accepted that such high quantum efficiency, can only be achieved with the use of organometallic phosphor doped OLEDs. Blue OLEDs are particularly important for solid state lighting. The simplest (and therefore likely the lowest cost) method of generating white light is to down convert part of the emission from a blue light source with a system of external phosphors. A second method of generating white light requires the superposition of the light from red, green and blue OLEDs in the correct ratio. Either of these two methods (and indeed any method of generating white light with a high color rendering index) critically depends on a high efficiency blue light component. A simple OLED generally consists of a hole-injecting anode, a preferentially hole transporting organic layer (HTL), an emissive layer that contains the recombination zone and ideally transports both holes and electrons, a preferentially electron-transporting layer (ETL) and an electron-injecting cathode. Color in state-of-the-art OLEDs is generated by an organometallic phosphor incorporated by co-sublimation into the emissive layer (EML). New materials functioning as hosts, emitters, charge transporting, and charge blocking layers have been developed along with device architectures leading to electrophosphorescent based OLEDs with high quantum efficiencies near the theoretical limit. However, the layers added to the device architecture to enable high quantum efficiencies lead to higher operating voltages and correspondingly lower power efficiencies. Achievement of target luminance power efficiencies will require new strategies for lowering

  6. Robust and Fragile Mathematical Identities: A Framework for Exploring Racialized Experiences and High Achievement among Black College Students

    Science.gov (United States)

    McGee, Ebony O.

    2015-01-01

    I introduce the construct of fragile and robust identities for the purpose of exploring the experiences that influenced the mathematical and racial identities of high-achieving Black college students in mathematics and engineering. These students maintained high levels of academic achievement in these fields while enduring marginalization,…

  7. Effects of full-time and part-time high-ability programs on developments in students’ achievement emotions

    NARCIS (Netherlands)

    Hornstra, L.; van der Veen, I.; Peetsma, T.

    2017-01-01

    This study focused on effects of high-ability programs on students’ achievement emotions, i.e. emotions that students experience that are associated with achievement activities. Participants were students in grade 4–6 of primary education: 218 students attended full-time high-ability programs, 245

  8. High school students with asthma: attitudes about school health, absenteeism, and its impact on academic achievement.

    Science.gov (United States)

    Krenitsky-Korn, Susan

    2011-01-01

    Asthma is the most frequent reason for absence from school; it accounts for one-third of all days of missed instruction, placing students at risk for academic failure and social isolation. This study compared high school students with asthma with those without asthma, and examined the relationship of their attitudes toward school health services, absenteeism, academic achievement, and the supposition that school nurse services play an essential part in the academic process. Surveys were completed by all students who participated in the study. Twenty-eight students with asthma reported levels of illness and school nurse support in an additional survey. Data revealed that students with asthma were absent more frequently, scored lower in mathematics, and participated less in school activities than their peers without asthma. Their level of illness did not predict the number of days absent, which was negatively correlated with achievement and positively correlated with students' permissive attitudes toward absenteeism. Findings indicate that school nurse interventions were sources of physical, social, emotional, and academic support.

  9. Characterizing Terrestrial Exoplanets

    Science.gov (United States)

    Meadows, V. S.; Lustig-Yaeger, J.; Lincowski, A.; Arney, G. N.; Robinson, T. D.; Schwieterman, E. W.; Deming, L. D.; Tovar, G.

    2017-11-01

    We will provide an overview of the measurements, techniques, and upcoming missions required to characterize terrestrial planet environments and evolution, and search for signs of habitability and life.

  10. Sarcopenia Is Negatively Related to High Gravitational Impacts Achieved From Day-to-day Physical Activity.

    Science.gov (United States)

    Hartley, April; Gregson, Celia L; Hannam, Kimberly; Deere, Kevin C; Clark, Emma M; Tobias, Jon H

    2018-04-17

    Sarcopenia has been associated with reduced physical activity (PA). We aimed to determine if sarcopenia, and specific components of muscle size, function, and physical performance, are associated with high impacts achieved during habitual PA, as these are related to bone strength in community-dwelling older women. Participants were older women from the Cohort of Skeletal Health in Bristol and Avon. We defined sarcopenia using the EWGSOP criteria. Lower limb peak muscle power and force were assessed using Jumping Mechanography (JM). High vertical impacts were assessed by tri-axial accelerometry (at least 1.5g above gravity). Cross-sectional associations were analyzed by linear regression, adjusting for age, height and weight (or fat mass for models including appendicular lean mass index), comorbidities, smoking, alcohol, and Index of Multiple Deprivation. Our analyses included 380 participants, with mean age 76.7 (SD 3.0) years; 242 (64%) also completed JM. In age-adjusted analysis, a negative relationship was observed between severity of sarcopenia and high, but not medium or low, impacts (p = .03 for trend). Regarding components of sarcopenia underlying this relationship, multivariable analyses revealed that gait speed (β 1.47 [95% CI 1.14, 1.89], [β-1] reflects the proportionate increase in high impacts per SD increase in exposure) and peak force (1.40 [1.07, 1.84]) were independently associated with high impacts. Older women with sarcopenia experienced fewer bone-strengthening high impacts than those with presarcopenia or without sarcopenia. To increase bone strengthening activity in older women, interventions need to improve both lower limb muscle force and walking speed.

  11. Achieving high-efficiency emission depletion nanoscopy by employing cross relaxation in upconversion nanoparticles.

    Science.gov (United States)

    Zhan, Qiuqiang; Liu, Haichun; Wang, Baoju; Wu, Qiusheng; Pu, Rui; Zhou, Chao; Huang, Bingru; Peng, Xingyun; Ågren, Hans; He, Sailing

    2017-10-20

    Stimulated emission depletion microscopy provides a powerful sub-diffraction imaging modality for life science studies. Conventionally, stimulated emission depletion requires a relatively high light intensity to obtain an adequate depletion efficiency through only light-matter interaction. Here we show efficient emission depletion for a class of lanthanide-doped upconversion nanoparticles with the assistance of interionic cross relaxation, which significantly lowers the laser intensity requirements of optical depletion. We demonstrate two-color super-resolution imaging using upconversion nanoparticles (resolution ~ 66 nm) with a single pair of excitation/depletion beams. In addition, we show super-resolution imaging of immunostained cytoskeleton structures of fixed cells (resolution ~ 82 nm) using upconversion nanoparticles. These achievements provide a new perspective for the development of photoswitchable luminescent probes and will broaden the applications of lanthanide-doped nanoparticles for sub-diffraction microscopic imaging.

  12. Achieving a high mode count in the exact electromagnetic simulation of diffractive optical elements.

    Science.gov (United States)

    Junker, André; Brenner, Karl-Heinz

    2018-03-01

    The application of rigorous optical simulation algorithms, both in the modal as well as in the time domain, is known to be limited to the nano-optical scale due to severe computing time and memory constraints. This is true even for today's high-performance computers. To address this problem, we develop the fast rigorous iterative method (FRIM), an algorithm based on an iterative approach, which, under certain conditions, allows solving also large-size problems approximation free. We achieve this in the case of a modal representation by avoiding the computationally complex eigenmode decomposition. Thereby, the numerical cost is reduced from O(N 3 ) to O(N log N), enabling a simulation of structures like certain diffractive optical elements with a significantly higher mode count than presently possible. Apart from speed, another major advantage of the iterative FRIM over standard modal methods is the possibility to trade runtime against accuracy.

  13. Achieving behavioral control with millisecond resolution in a high-level programming environment.

    Science.gov (United States)

    Asaad, Wael F; Eskandar, Emad N

    2008-08-30

    The creation of psychophysical tasks for the behavioral neurosciences has generally relied upon low-level software running on a limited range of hardware. Despite the availability of software that allows the coding of behavioral tasks in high-level programming environments, many researchers are still reluctant to trust the temporal accuracy and resolution of programs running in such environments, especially when they run atop non-real-time operating systems. Thus, the creation of behavioral paradigms has been slowed by the intricacy of the coding required and their dissemination across labs has been hampered by the various types of hardware needed. However, we demonstrate here that, when proper measures are taken to handle the various sources of temporal error, accuracy can be achieved at the 1 ms time-scale that is relevant for the alignment of behavioral and neural events.

  14. Conflicts and communication between high-achieving Chinese American adolescents and their parents.

    Science.gov (United States)

    Qin, Desiree Baolian; Chang, Tzu-Fen; Han, Eun-Jin; Chee, Grace

    2012-01-01

    Drawing on in-depth interview data collected on 18 high-achieving Chinese American students, the authors examine domains of acculturation-based conflicts, parent and child internal conflicts, and conflict resolution in their families. Their analyses show that well-established negative communication patterns in educational expectations, divergent attitudes toward other races and country of origin, and cultural and language barriers contributed to parent-child conflicts. Their findings also illustrate important internal conflicts both adolescents and parents had along the cultural tightrope of autonomy and relatedness. Finally, the vertical in-group conflict resolution style that was evidenced in youths' accounts raises questions about cultural differences in constructive versus destructive conflict resolution styles. © 2012 Wiley Periodicals, Inc., A Wiley Company.

  15. Achieving High-Energy-High-Power Density in a Flexible Quasi-Solid-State Sodium Ion Capacitor.

    Science.gov (United States)

    Li, Hongsen; Peng, Lele; Zhu, Yue; Zhang, Xiaogang; Yu, Guihua

    2016-09-14

    Simultaneous integration of high-energy output with high-power delivery is a major challenge for electrochemical energy storage systems, limiting dual fine attributes on a device. We introduce a quasi-solid-state sodium ion capacitor (NIC) based on a battery type urchin-like Na2Ti3O7 anode and a capacitor type peanut shell derived carbon cathode, using a sodium ion conducting gel polymer as electrolyte, achieving high-energy-high-power characteristics in solid state. Energy densities can reach 111.2 Wh kg(-1) at power density of 800 W kg(-1), and 33.2 Wh kg(-1) at power density of 11200 W kg(-1), which are among the best reported state-of-the-art NICs. The designed device also exhibits long-term cycling stability over 3000 cycles with capacity retention ∼86%. Furthermore, we demonstrate the assembly of a highly flexible quasi-solid-state NIC and it shows no obvious capacity loss under different bending conditions.

  16. The realistic performance achievable with mycobacterial automated culture systems in high and low prevalence settings

    Directory of Open Access Journals (Sweden)

    Klatser Paul R

    2010-04-01

    Full Text Available Abstract Background Diagnostic tests are generally used in situations with similar pre-test probability of disease to where they were developed. When these tests are applied in situations with very different pre-test probabilities of disease, it is informative to model the likely implications of known characteristics of test performance in the new situation. This is the case for automated Mycobacterium tuberculosis (MTB liquid culture systems for tuberculosis case detection which were developed and are widely used in low burden settings but are only beginning to be applied on a large scale in high burden settings. Methods Here we model the performance of MTB liquid culture systems in high and low tuberculosis (TB prevalence settings using detailed published data concentrating on the likely frequency of cross-contamination events. Results Our model predicts that as the TB prevalence in the suspect population increases there is an exponential increase in the risk of MTB cross-contamination events expected in otherwise negative samples, even with equivalent technical performance of the laboratories. Quality control and strict cross-contamination measures become increasingly critical as the burden of MTB infection among TB suspects increases. Even under optimal conditions the realistically achievable specificity of these systems in high burden settings will likely be significantly below that obtained in low TB burden laboratories. Conclusions Liquid culture systems can play a valuable role in TB case detection in laboratories in high burden settings, but laboratory workers, policy makers and clinicians should be aware of the increased risks, independent of laboratory proficiency, of cross-contamination events in high burden settings.

  17. Why Try? Factors that Differentiate Underachieving Gifted Students from High Achieving Gifted Students.

    Science.gov (United States)

    McCoach, D. Betsy; Siegle, Del

    This report discusses the outcomes of a study that investigated the relationship between student scores on the five sub-scales of the School Attitude Assessment Survey-Revised (SAAS-R) and the academic achievement of known groups of gifted achievers and gifted underachievers. The study examined whether gifted achievers and gifted underachievers…

  18. Held Back: The Impact of Curricular and Pedagogical Factors on Tested Achievement in High School Mathematics

    Science.gov (United States)

    Agvanian, Zara

    2013-01-01

    This study examined the impact of curricular factors and teaching practices on students' tested achievement in mathematics, explored the best predictors of the tested achievement, and examined differences in the tested achievement among student subgroups. The study utilized qualitative and quantitative methods and triangulated findings from…

  19. Do high levels of diffuse and chronic metal pollution in sediments of Rhine and Meuse floodplains affect structure and functioning of terrestrial ecosystems?

    International Nuclear Information System (INIS)

    Rozema, Jelte; Notten, Martje J.M.; Aerts, Rien; Gestel, Cornelis A.M. van; Hobbelen, Peter H.F.; Hamers, Timo H.M.

    2008-01-01

    This paper (re)considers the question if chronic and diffuse heavy metal pollution (cadmium, copper, lead and zinc) affects the structure and functioning of terrestrial ecosystems of Biesbosch National Park, the floodplain area of rivers Meuse and Rhine. To reach this aim, we integrated the results of three projects on: 1. the origin, transfer and effects of heavy metals in a soil-plant-snail food chain; 2. the impact of bioavailability on effects of heavy metals on the structure and functioning of detritivorous communities; 3. the risk assessment of heavy metals for an herbivorous and a carnivorous small mammal food chain. Metal pollution levels of the Biesbosch floodplain soils are high. The bioavailability of metals in the soils is low, causing low metal levels in plant leaves. Despite this, metal concentrations in soil dwelling detritivores and in land snails at polluted locations are elevated in comparison to animals from 'non-polluted' reference sites. However, no adverse effects on ecosystem structure (species richness, density, biomass) and functioning (litter decomposition, leaf consumption, reproduction) have been found. Sediment metal pollution may pose a risk to the carnivorous small mammal food chain, in which earthworms with elevated metal concentrations are eaten by the common shrew. Additional measurements near an active metal smelter, however, show reduced leaf consumption rates and reduced reproduction by terrestrial snails, reflecting elevated metal bioavailability at this site. Since future management may also comprise reintroduction of tidal action in the Biesbosch area, changes in metal bioavailability, and as a consequence future ecosystem effects, cannot be excluded

  20. Puncturevine (Tribulus terrestris L.: noxious weed or powerful medical herb

    Directory of Open Access Journals (Sweden)

    Zvonko Pacanoski

    2014-03-01

    Full Text Available Tribulus terrestris L., an annual dicot species of the family Zygophyllaceae, is a common herb that is often found in disturbed habitats and agricultural areas in many parts of the temperate, tropical and desert regions of the world. T. terrestris is an aggressive species that has the potential to injure livestock, reduce hay and wool values, detour recreationists and reduces plant biodivesity. The species may become troublesome because of its weedy potential. It has been declared a weed in at least 37 countries and in at least 21 crops (cotton, maize, vineyards, orchards, etc.. It is adapted to a wide range of climatic conditions and grows on a wide variety of soil types. The management of T. terrestris can be achieved by herbicide application, mechanical (hand pulling, hoeing, mulching and biological control methods. Beside its invasive potential as a noxious and troublesome weed, T. terrestris is considered highly useful herb which is used for various purposes in folk and modern medicine and sport, as well.

  1. V. Terrestrial vertebrates

    Science.gov (United States)

    Dean Pearson; Deborah Finch

    2011-01-01

    Within the Interior West, terrestrial vertebrates do not represent a large number of invasive species relative to invasive weeds, aquatic vertebrates, and invertebrates. However, several invasive terrestrial vertebrate species do cause substantial economic and ecological damage in the U.S. and in this region (Pimental 2000, 2007; Bergman and others 2002; Finch and...

  2. Achieving Energy Savings with Highly-Controlled Lighting in an Open-Plan Office

    Energy Technology Data Exchange (ETDEWEB)

    Rubinstein, Francis; Enscoe, Abby

    2010-04-19

    An installation in a Federal building tested the effectiveness of a highly-controlled, workstation-specific lighting retrofit. The study took place in an open-office area with 86 cubicles and low levels of daylight. Each cubicle was illuminated by a direct/indirectpendant luminaire with three 32 watt lamps, two dimmable DALI ballasts, and an occupancy sensor. A centralized control system programmed all three lamps to turn on and off according to occupancy on a workstation-by-workstation basis. Field measurements taken over the course of several monthsdemonstrated 40% lighting energy savings compared to a baseline without advanced controls that conforms to GSA's current retrofit standard. A photometric analysis found that the installation provided higher desktop light levels than the baseline, while an occupant survey found that occupants in general preferred the lighting system to thebaseline.Simple payback is fairly high; projects that can achieve lower installation costs and/or higher energy savings and those in which greenhouse gas reduction and occupant satisfaction are significant priorities provide the ideal setting for workstation-specific lighting retrofits.

  3. Important aspects for consideration in minimizing plant outage times. Swiss experience in achieving high availability

    International Nuclear Information System (INIS)

    Malcotsis, G.

    1984-01-01

    Operation of Swiss nuclear power plants has not been entirely free of trouble. They have experienced defective fuel elements, steam generator tube damage, excessive vibration of the core components, leakages in the recirculation pump seals and excessive corrosion and erosion in the steam-feedwater plant. Despite these technical problems in the early life of the plants, on overall balance the plants can be considered to have performed exceedingly well. The safety records from more than 40 reactor-years of operation are excellent and, individually and collectively, the capacity factors obtained are among the highest in the world. The problems mentioned have been solved and the plants continue operation with high availabilities. This success can be attributed to the good practices of the utilities with regard to the choice of special design criteria, plant organization, plant operation and plant maintenance, and also to the pragmatic approach of the licensing authorities and their consultants to quality assurance and quality control. The early technical problems encountered, the corresponding solutions adopted and the factors that contributed towards achieving high availabilities in Swiss nuclear power plants are briefly described. (author)

  4. Comparison of therapeutic lipid target achievements among high-risk patients in Oman.

    Science.gov (United States)

    Al-Waili, Khalid; Al-Zakwani, Ibrahim; Al-Dughaishi, Tamima; Baneerje, Yajnavalka; Al-Sabti, Hilal; Al-Hashmi, Khamis; Farhan, Hatem; Habsi, Khadija Al; Al-Hinai, Ali T; Al-Rasadi, Khalid

    2014-05-01

    We compared therapeutic lipid target achievements among patients with diabetes or coronary heart disease (CHD) in Oman. A retrospective chart review of 94 patients was conducted at an outpatient clinic in Sultan Qaboos University Hospital, Muscat, Oman. The variables included low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and apolipoprotein B (apo B). The overall mean age of the cohort was 59 ± 12 years, 54% were male, 66% were diabetic, 48% hypertensive, 45% had CHD, 94% were on simvastatin, 4% were on fenofibrate, and 2% were on both simvastatin and fenofibrate. Lipid goal attainments of calculated LDL-C (<2.6 mmol/L), apo B (<0.9 g/L), and non-HDL-C (<3.36 mmol/L) were reached in 52%, 39%, and 53% of the patients, respectively. A significant proportion of high-risk patients treated with lipid-lowering agents reach LDL-C but not the apo B treatment targets, suggesting that the use of apo B target values should also be considered.

  5. High-order harmonic generation in a laser plasma: a review of recent achievements

    International Nuclear Information System (INIS)

    Ganeev, R A

    2007-01-01

    A review of studies of high-order harmonic generation in plasma plumes is presented. The generation of high-order harmonics (up to the 101st order, λ = 7.9 nm) of Ti:sapphire laser radiation during the propagation of short laser pulses through a low-excited, low-ionized plasma produced on the surfaces of different targets is analysed. The observation of considerable resonance-induced enhancement of a single harmonic (λ = 61.2 nm) at the plateau region with 10 -4 conversion efficiency in the case of an In plume can offer some expectations that analogous processes can be realized in other plasma samples in the shorter wavelength range. Recent achievements of single-harmonic enhancement at mid- and end-plateau regions are discussed. Various methods for the optimization of harmonic generation are analysed, such as the application of the second harmonic of driving radiation and the application of prepulses of different durations. The enhancement of harmonic generation efficiency during the propagation of femtosecond pulses through a nanoparticle-containing plasma is discussed. (topical review)

  6. Autonomous Information Fading and Provision to Achieve High Response Time in Distributed Information Systems

    Science.gov (United States)

    Lu, Xiaodong; Arfaoui, Helene; Mori, Kinji

    In highly dynamic electronic commerce environment, the need for adaptability and rapid response time to information service systems has become increasingly important. In order to cope with the continuously changing conditions of service provision and utilization, Faded Information Field (FIF) has been proposed. FIF is a distributed information service system architecture, sustained by push/pull mobile agents to bring high-assurance of services through a recursive demand-oriented provision of the most popular information closer to the users to make a tradeoff between the cost of information service allocation and access. In this paper, based on the analysis of the relationship that exists among the users distribution, information provision and access time, we propose the technology for FIF design to resolve the competing requirements of users and providers to improve users' access time. In addition, to achieve dynamic load balancing with changing users preference, the autonomous information reallocation technology is proposed. We proved the effectiveness of the proposed technology through the simulation and comparison with the conventional system.

  7. Influence of gross saponins from tribulus terrestris L on SOD activity and MDA content for chronic high intraocular pressure in rabbit

    Directory of Open Access Journals (Sweden)

    Nuo Li

    2013-05-01

    Full Text Available AIM:To observe influence of gross saponins from tribulus terrestris L(GSTTon SOD activity and MDA content for chronic high intraocular pressure in rabbit, and discusses the retina oxidative damage inhibition on chronic high intraocular pressure model of rabbit. METHODS:Totally 24 healthy New Zealand rabbits were randomly divided into 4 groups: normal control group(A group; high intraocular pressure model blank group(B group; high intraocular pressure model with GSTT treated group(C group; high intraocular pressure model with Erigeron brevicapas hand mass(EBHMtreated group(D group. High intraocular pressure model was induced by 20g/L methylcellulose injection into the anterior chamber in B group, C group and D group. D group was injected 5 mg/kg GSTT and C group was injected 4.5mg/kg EBHM and measured intraocular pressure with Schiotz tonometer every day for 4 weeks. The retina tissue superoxide dismutase(SODand maleic dialdehyde(MDAcontent were detected 28 days later. RESULTS: After glaucoma model of rabbit eyes were established, the intraocular pressure during observation period was maintained in 32-39mmHg; High intraocular pressure model blank group and normal control group, EBHM treatment group, GSTT treatment group were compared, the differences of retina MDA, SOD content had statistical significance(P0.05; EBHM treatment group, GSTT treatment group and normal control group were compared, the content of MDA in the retina was still slightly higher(P<0.05, the content of SOD slightly lower(P<0.05 CONCLUSION: GSTT can effectively improve the retina SOD activity of chronic high intraocular pressure in rabbit and reduce the content of MDA, which has a protective effect of persistent high intraocular retinal oxidative stress.

  8. The relationship between family atmosphere and motivation for achievement in year 12 high school students in Yazd 2006-2007

    Directory of Open Access Journals (Sweden)

    G.A Heidary

    2012-02-01

    Results: Six factors were analyzed as predictors of achievement motivation including (rational, cultural based, ethical, religious circuit, control and organization. None of them were significant predictors. The relationship between gender and achievement motivation were significant. A correlation between gender, family atmosphere and achievement motivation was not observed in this study. Conclusion: The family atmosphere with various aspects of motivation may effect on development of students and educational success in Yazd high school students.

  9. Qualitative research study of high-achieving females' life experiences impacting success

    Science.gov (United States)

    Butcher, Ann Patrice

    2003-07-01

    This qualitative study investigated the life experiences of five academically gifted female students in math and science in reflection of their elementary learning prior to enrollment at a prestigious science and mathematics high school. The elite high school limits admission to the state of Illinois' top students. The purpose of this study is to unfold the story of five academically gifted females in attendance at the elite high school reflecting on their life experiences in elementary school that contributed to their current academic success. Twelve female students, who at the time of this study were currently in their senior year (12th grade) of high school, were solicited from the top academic groups who are regarded by their teachers as highly successful in class. Students were selected as part of the study based on academic status, survey completion and interest in study, Caucasian and Asian ethnicity, locale of elementary school with preference given to the variety of school demographics---urban, suburban, and rural---further defined the group to the core group of five. All female participants were personally interviewed and communicated via Internet with the researcher. Parents and teachers completing surveys as well met the methodological requirements of triangulation. An emergent theme of paternal influence came from the research. Implications supported in the research drawn from this study to increase achievement of academically gifted females include: (a) proper early identification of learner strengths plays a role; (b) learning with appropriate intellectual peers is more important than learning with their age group; (c) teachers are the greatest force for excellent instruction; (d) effective teaching strategies include cooperative learning, multi-sensory learning, problem-based learning, and hands-on science; (e) rigor in math is important; (f) gender and stereotypes need not be barriers; (g) outside interests and activities are important for self

  10. Longitudinal Outcomes of Start Time Delay on Sleep, Behavior, and Achievement in High School

    Science.gov (United States)

    Thacher, Pamela V.; Onyper, Serge V.

    2016-01-01

    Study Objectives: To establish whether sleep, health, mood, behavior, and academics improved after a 45-minute delay in high school start time, and whether changes persisted longitudinally. Methods: We collected data from school records and student self-report across a number of domains at baseline (May 2012) and at two follow-up time points (November 2012 and May 2013), at a public high school in upstate New York. Students enrolled during academic years (AY) 2011–2012 and 2012–2013 completed the Pittsburgh Sleep Quality Index; the DASS-21; the “Owl-Lark” Scale; the Daytime Sleepiness Index; and a brief self-report of health. Reports from school records regarding attendance, tardiness, disciplinary violations, and academic performance were collected for AY 2010–2011 through 2013–2014. Results: Students delayed but did not extend their sleep period; we found lasting improvements in tardiness and disciplinary violations after the start-time delay, but no changes to other variables. At the first follow-up, students reported 20 minutes longer sleep, driven by later rise times and stable bed times. At the second follow-up, students maintained later rise times but delayed bedtimes, returning total sleep to baseline levels. A delay in rise time, paralleling the delay in the start time that occurred, resulted in less tardiness and decreased disciplinary incidents, but larger improvements to sleep patterns may be necessary to affect health, attendance, sleepiness, and academic performance. Conclusions: Later start times improved tardiness and disciplinary issues at this school district. A delay in start time may be a necessary but not sufficient means to increase sleep time and may depend on preexisting individual differences. Commentary: A commentary on this article appears in this issue on page 267. Citation: Thacher PV, Onyper SV. Longitudinal outcomes of start time delay on sleep, behavior, and achievement in high school. SLEEP 2016;39(2):271–281. PMID

  11. High heat flux testing impact on the Tore Supra toroidal pumped limiter achievement

    International Nuclear Information System (INIS)

    Schlosser, J.; Escourbiac, F.; Cordier, J.J.; Mitteau, R.; Durocher, A.; Grosman, A.

    2003-01-01

    The toroidal pumped limiter of Tore Supra is made of 576 elementary high heat flux (HHF) cooled plasma-facing components (PFCs) and designed to sustain 10 MW/m 2 in steady state. One of the main technical difficulties is to ensure a high quality of the bond between the carbon fiber composite armor tile and the water-cooled heat sink due to the high thermal stresses that develop at the bond during operation. Consequently, a HHF facility able to reproduce in service operation of PFCs is required all along the development and manufacturing route. In Europe, the FE200 facility (electron beam, 200 kW, France) operating since 1991, was extensively used for such a development. A first testing campaign in 1995 was devoted to the qualification of this bond: AMC technology from Plansee GmbH was selected. Afterwards, a second campaign on scale-one elements (1996) allowed an optimization of the element design and series production to be launched. During the mass production, a non-destructive control process - cheaper and faster than HHF testing - based on infrared characterization was routinely operated on 100% of the manufactured elements. Strong variability of the bond quality was observed and a repair process allowing the replacement of deficient tiles was developed. In 2000 and 2001, 2 campaigns of HHF testing were launched to correlate the non-destructive measurements and to optimize and validate the repair process. This was done, in two steps, with success. This yielded moreover interesting information for qualifying both tests across each other and also to analyze the fatigue evolution of the bond. The qualification and the achievement of the Tore Supra limiter has greatly been made possible by such HHF tests, which appears as essential before and during PFC manufacturing. (authors)

  12. A comparison of rural high school students in Germany with rural Tennessee high school students' mathematics and science achievement

    Science.gov (United States)

    Harding, R. Fredrick

    This descriptive study compared the science and mathematics aptitudes and achievement test scores for the final school year students in rural White County and Van Buren County, Tennessee with rural county students in Germany. In accordance with the previous research literature (Stevenson, 2002), German students outperformed U.S. students on The International Trends in Math and Science test (TIMSS). As reform in the U.S. education system has been underway, this study intended to compare German county student final school year performance with White County and Van Buren County (Grade 12) performance in science and mathematics. The entire populations of 176 White and Van Buren Counties senior high final school year students were compared with 120 school final year students from two rural German county high schools. The student responses to identical test and questionnaire items were compared using the t-test statistical analysis. In conclusion after t-test analyses, there was no significant difference (p>.05 level) in student attitudes on the 27 problem achievement and the 35 TIMSS questionnaire items between the sampled population of 120 German students compared with the population of 176 White and Van Buren students. Also, there was no statistically significant difference (p>.05 level) between the German, White, and Van Buren County rural science and math achievement in the TIMSS problem section of the final year test. Based on the research, recommendations to improve U.S. student scores to number one in the world include making changes in teaching methodology in mathematics and science; incorporating pamphlet lessons rather than heavily reliance on textbooks; focusing on problem solving; establishing an online clearinghouse for effective lessons; creating national standards in mathematics and science; matching students' course choices to job aspirations; tracking misbehaving students rather than mainstreaming them into the regular classroom; and designing

  13. Extrinsic Motivation for Large-Scale Assessments: A Case Study of a Student Achievement Program at One Urban High School

    Science.gov (United States)

    Emmett, Joshua; McGee, Dean

    2013-01-01

    The purpose of this case study was to discover the critical attributes of a student achievement program, known as "Think Gold," implemented at one urban comprehensive high school as part of the improvement process. Student achievement on state assessments improved during the period under study. The study draws upon perspectives on…

  14. American High School Students from Different Ethnic Backgrounds: The Role of Parents and the Classroom in Achievement Motivation

    Science.gov (United States)

    Kim, Jung-In

    2015-01-01

    The purpose of this study was to investigate the relationships between ethnically diverse US high school students' (N = 331) perceptions of their parents' or classroom's motivating factors and their achievement motivation in their math class, connecting achievement goal orientation and self-determination theories. Two hypothesized path models were…

  15. Balance the Carrier Mobility To Achieve High Performance Exciplex OLED Using a Triazine-Based Acceptor.

    Science.gov (United States)

    Hung, Wen-Yi; Chiang, Pin-Yi; Lin, Shih-Wei; Tang, Wei-Chieh; Chen, Yi-Ting; Liu, Shih-Hung; Chou, Pi-Tai; Hung, Yi-Tzu; Wong, Ken-Tsung

    2016-02-01

    A star-shaped 1,3,5-triazine/cyano hybrid molecule CN-T2T was designed and synthesized as a new electron acceptor for efficient exciplex-based OLED emitter by mixing with a suitable electron donor (Tris-PCz). The CN-T2T/Tris-PCz exciplex emission shows a high ΦPL of 0.53 and a small ΔET-S = -0.59 kcal/mol, affording intrinsically efficient fluorescence and highly efficient exciton up-conversion. The large energy level offsets between Tris-PCz and CN-T2T and the balanced hole and electron mobility of Tris-PCz and CN-T2T, respectively, ensuring sufficient carrier density accumulated in the interface for efficient generation of exciplex excitons. Employing a facile device structure composed as ITO/4% ReO3:Tris-PCz (60 nm)/Tris-PCz (15 nm)/Tris-PCz:CN-T2T(1:1) (25 nm)/CN-T2T (50 nm)/Liq (0.5 nm)/Al (100 nm), in which the electron-hole capture is efficient without additional carrier injection barrier from donor (or acceptor) molecule and carriers mobilities are balanced in the emitting layer, leads to a highly efficient green exciplex OLED with external quantum efficiency (EQE) of 11.9%. The obtained EQE is 18% higher than that of a comparison device using an exciplex exhibiting a comparable ΦPL (0.50), in which TCTA shows similar energy levels but higher hole mobility as compared with Tris-PCz. Our results clearly indicate the significance of mobility balance in governing the efficiency of exciplex-based OLED. Exploiting the Tris-PCz:CN-T2T exciplex as the host, we further demonstrated highly efficient yellow and red fluorescent OLEDs by doping 1 wt % Rubrene and DCJTB as emitter, achieving high EQE of 6.9 and 9.7%, respectively.

  16. Safety management systems and their role in achieving high standards of operational safety

    International Nuclear Information System (INIS)

    Coulston, D.J.; Baylis, C.C.

    2000-01-01

    Achieving high standards of operational safety requires a robust management framework that is visible to all personnel with responsibility for its implementation. The structure of the management framework must ensure that all processes used to manage safety interlink in a logical and coherent manner, that is, they form a management system that leads to continuous improvement in safety performance. This Paper describes BNFL's safety management system (SMS). The SMS has management processes grouped within 5 main elements: 1. Policy, 2. Organisation, 3. Planning and Implementation, 4. Measuring and Reviewing Performance, 5. Audit. These elements reflect the overall process of setting safety objective (from Policy), measuring success and reviewing the performance. Effective implementation of the SMS requires senior managers to demonstrate leadership through their commitment and accountability. However, the SMS as a whole reflects that every employee at every level within BNFL is responsible for safety of operations under their control. The SMS therefore promotes a proactive safety culture and safe operations. The system is formally documented in the Company's Environmental, Health and Safety (EHS) Manual. Within in BNFL Group, the Company structures enables the Manual to provide overall SMS guidance and co-ordination to its range of nuclear businesses. Each business develops the SMS to be appropriate at all levels of its organisation, but ensuring that each level is consistent with the higher level. The Paper concludes with a summary of BNFL's safety performance. (author)

  17. Quantifying volume loss from ice cliffs on debris-covered glaciers using high-resolution terrestrial and aerial photogrammetry

    NARCIS (Netherlands)

    Brun, Fanny; Buri, Pascal; Miles, Evan S.; Wagnon, Patrick; Steiner, J.F.; Berthier, Etienne; Ragettli, S.; Kraaijenbrink, P.D.A.; Immerzeel, W.W.; Pellicciotti, Francesca

    Mass losses originating from supraglacial ice cliffs at the lower tongues of debris-covered glaciers are a potentially large component of the mass balance, but have rarely been quantified. In this study, we develop a method to estimate ice cliff volume losses based on high-resolution topographic

  18. Achieving numerical accuracy and high performance using recursive tile LU factorization with partial pivoting

    KAUST Repository

    Dongarra, Jack

    2013-09-18

    The LU factorization is an important numerical algorithm for solving systems of linear equations in science and engineering and is a characteristic of many dense linear algebra computations. For example, it has become the de facto numerical algorithm implemented within the LINPACK benchmark to rank the most powerful supercomputers in the world, collected by the TOP500 website. Multicore processors continue to present challenges to the development of fast and robust numerical software due to the increasing levels of hardware parallelism and widening gap between core and memory speeds. In this context, the difficulty in developing new algorithms for the scientific community resides in the combination of two goals: achieving high performance while maintaining the accuracy of the numerical algorithm. This paper proposes a new approach for computing the LU factorization in parallel on multicore architectures, which not only improves the overall performance but also sustains the numerical quality of the standard LU factorization algorithm with partial pivoting. While the update of the trailing submatrix is computationally intensive and highly parallel, the inherently problematic portion of the LU factorization is the panel factorization due to its memory-bound characteristic as well as the atomicity of selecting the appropriate pivots. Our approach uses a parallel fine-grained recursive formulation of the panel factorization step and implements the update of the trailing submatrix with the tile algorithm. Based on conflict-free partitioning of the data and lockless synchronization mechanisms, our implementation lets the overall computation flow naturally without contention. The dynamic runtime system called QUARK is then able to schedule tasks with heterogeneous granularities and to transparently introduce algorithmic lookahead. The performance results of our implementation are competitive compared to the currently available software packages and libraries. For example

  19. Achieving numerical accuracy and high performance using recursive tile LU factorization with partial pivoting

    KAUST Repository

    Dongarra, Jack; Faverge, Mathieu; Ltaief, Hatem; Luszczek, Piotr R.

    2013-01-01

    The LU factorization is an important numerical algorithm for solving systems of linear equations in science and engineering and is a characteristic of many dense linear algebra computations. For example, it has become the de facto numerical algorithm implemented within the LINPACK benchmark to rank the most powerful supercomputers in the world, collected by the TOP500 website. Multicore processors continue to present challenges to the development of fast and robust numerical software due to the increasing levels of hardware parallelism and widening gap between core and memory speeds. In this context, the difficulty in developing new algorithms for the scientific community resides in the combination of two goals: achieving high performance while maintaining the accuracy of the numerical algorithm. This paper proposes a new approach for computing the LU factorization in parallel on multicore architectures, which not only improves the overall performance but also sustains the numerical quality of the standard LU factorization algorithm with partial pivoting. While the update of the trailing submatrix is computationally intensive and highly parallel, the inherently problematic portion of the LU factorization is the panel factorization due to its memory-bound characteristic as well as the atomicity of selecting the appropriate pivots. Our approach uses a parallel fine-grained recursive formulation of the panel factorization step and implements the update of the trailing submatrix with the tile algorithm. Based on conflict-free partitioning of the data and lockless synchronization mechanisms, our implementation lets the overall computation flow naturally without contention. The dynamic runtime system called QUARK is then able to schedule tasks with heterogeneous granularities and to transparently introduce algorithmic lookahead. The performance results of our implementation are competitive compared to the currently available software packages and libraries. For example

  20. Achieving accurate simulations of urban impacts on ozone at high resolution

    International Nuclear Information System (INIS)

    Li, J; Georgescu, M; Mahalov, A; Moustaoui, M; Hyde, P

    2014-01-01

    The effects of urbanization on ozone levels have been widely investigated over cities primarily located in temperate and/or humid regions. In this study, nested WRF-Chem simulations with a finest grid resolution of 1 km are conducted to investigate ozone concentrations [O 3 ] due to urbanization within cities in arid/semi-arid environments. First, a method based on a shape preserving Monotonic Cubic Interpolation (MCI) is developed and used to downscale anthropogenic emissions from the 4 km resolution 2005 National Emissions Inventory (NEI05) to the finest model resolution of 1 km. Using the rapidly expanding Phoenix metropolitan region as the area of focus, we demonstrate the proposed MCI method achieves ozone simulation results with appreciably improved correspondence to observations relative to the default interpolation method of the WRF-Chem system. Next, two additional sets of experiments are conducted, with the recommended MCI approach, to examine impacts of urbanization on ozone production: (1) the urban land cover is included (i.e., urbanization experiments) and, (2) the urban land cover is replaced with the region’s native shrubland. Impacts due to the presence of the built environment on [O 3 ] are highly heterogeneous across the metropolitan area. Increased near surface [O 3 ] due to urbanization of 10–20 ppb is predominantly a nighttime phenomenon while simulated impacts during daytime are negligible. Urbanization narrows the daily [O 3 ] range (by virtue of increasing nighttime minima), an impact largely due to the region’s urban heat island. Our results demonstrate the importance of the MCI method for accurate representation of the diurnal profile of ozone, and highlight its utility for high-resolution air quality simulations for urban areas. (letter)

  1. Social Adaptation and Its Relationship to Achievement Motivation among High School Students in Jordan

    Science.gov (United States)

    AlZboon, Saleem Odeh

    2013-01-01

    The study amid at exploring and detecting the level of social adaptation and its relationship with the achievement motivation of the secondary school students in Jordan, the study sample consisted of 495 secondary school students in the province of Jerash, and to achieve the objective of this study comes the development of two tools: the first one…

  2. Academic Achievement and Extracurricular School Activities of At-Risk High School Students

    Science.gov (United States)

    Marchetti, Ryan; Wilson, Randal H.; Dunham, Mardis

    2016-01-01

    This study compared the employment, extracurricular participation, and family structure status of students from low socioeconomic families that achieved state-approved benchmarks on ACT reading and mathematics tests to those that did not achieve the benchmarks. Free and reduced lunch eligibility was used to determine SES. Participants included 211…

  3. Motivational Factors Contributing to Turkish High School Students' Achievement in Gases and Chemical Reactions

    Science.gov (United States)

    Kadioglu, Cansel; Uzuntiryaki, Esen

    2008-01-01

    This study aimed to investigate the contribution of motivational factors to 10th grade students' achievement in gases and chemical reactions in chemistry. Three hundred fifty nine 10th grade students participated in the study. The Gases and Chemical Reactions Achievement Test and the Motivated Strategies for Learning Questionnaire were…

  4. Relationships of cognitive and metacognitive learning strategies to mathematics achievement in four high-performing East Asian education systems.

    Science.gov (United States)

    Areepattamannil, Shaljan; Caleon, Imelda S

    2013-01-01

    The authors examined the relationships of cognitive (i.e., memorization and elaboration) and metacognitive learning strategies (i.e., control strategies) to mathematics achievement among 15-year-old students in 4 high-performing East Asian education systems: Shanghai-China, Hong Kong-China, Korea, and Singapore. In all 4 East Asian education systems, memorization strategies were negatively associated with mathematics achievement, whereas control strategies were positively associated with mathematics achievement. However, the association between elaboration strategies and mathematics achievement was a mixed bag. In Shanghai-China and Korea, elaboration strategies were not associated with mathematics achievement. In Hong Kong-China and Singapore, on the other hand, elaboration strategies were negatively associated with mathematics achievement. Implications of these findings are briefly discussed.

  5. What's Past is Prologue: Relations Between Early Mathematics Knowledge and High School Achievement.

    Science.gov (United States)

    Watts, Tyler W; Duncan, Greg J; Siegler, Robert S; Davis-Kean, Pamela E

    2014-10-01

    Although previous research has established the association between early-grade mathematics knowledge and later mathematics achievement, few studies have measured mathematical skills prior to school entry, nor have they investigated the predictive power of early gains in mathematics ability. The current paper relates mathematical skills measured at 54 months to adolescent mathematics achievement using multi-site longitudinal data. We find that preschool mathematics ability predicts mathematics achievement through age 15, even after accounting for early reading, cognitive skills, and family and child characteristics. Moreover, we find that growth in mathematical ability between age 54 months and first grade is an even stronger predictor of adolescent mathematics achievement. These results demonstrate the importance of pre-kindergarten mathematics knowledge and early math learning for later achievement.

  6. What’s Past is Prologue: Relations Between Early Mathematics Knowledge and High School Achievement

    Science.gov (United States)

    Watts, Tyler W.; Duncan, Greg J.; Siegler, Robert S.; Davis-Kean, Pamela E.

    2015-01-01

    Although previous research has established the association between early-grade mathematics knowledge and later mathematics achievement, few studies have measured mathematical skills prior to school entry, nor have they investigated the predictive power of early gains in mathematics ability. The current paper relates mathematical skills measured at 54 months to adolescent mathematics achievement using multi-site longitudinal data. We find that preschool mathematics ability predicts mathematics achievement through age 15, even after accounting for early reading, cognitive skills, and family and child characteristics. Moreover, we find that growth in mathematical ability between age 54 months and first grade is an even stronger predictor of adolescent mathematics achievement. These results demonstrate the importance of pre-kindergarten mathematics knowledge and early math learning for later achievement. PMID:26806961

  7. Creation of High Resolution Terrain Models of Barringer Meteorite Crater (Meteor Crater) Using Photogrammetry and Terrestrial Laser Scanning Methods

    Science.gov (United States)

    Brown, Richard B.; Navard, Andrew R.; Holland, Donald E.; McKellip, Rodney D.; Brannon, David P.

    2010-01-01

    Barringer Meteorite Crater or Meteor Crater, AZ, has been a site of high interest for lunar and Mars analog crater and terrain studies since the early days of the Apollo-Saturn program. It continues to be a site of exceptional interest to lunar, Mars, and other planetary crater and impact analog studies because of its relatively young age (est. 50 thousand years) and well-preserved structure. High resolution (2 meter to 1 decimeter) digital terrain models of Meteor Crater in whole or in part were created at NASA Stennis Space Center to support several lunar surface analog modeling activities using photogrammetric and ground based laser scanning techniques. The dataset created by this activity provides new and highly accurate 3D models of the inside slope of the crater as well as the downslope rock distribution of the western ejecta field. The data are presented to the science community for possible use in furthering studies of Meteor Crater and impact craters in general as well as its current near term lunar exploration use in providing a beneficial test model for lunar surface analog modeling and surface operation studies.

  8. Tidally Heated Terrestrial Exoplanets

    Science.gov (United States)

    Henning, Wade Garrett

    This work models the surface and internal temperatures for hypothetical terrestrial planets in situations involving extreme tidal heating. The feasibility of such planets is evaluated in terms of the orbital perturbations that may give rise to them, their required proximity to a hoststar, and the potential for the input tidal heating to cause significant partial melting of the mantle. Trapping terrestrial planets into 2:1 resonances with migrating Hot Jupiters is considered as a reasonable way for Earth-like worlds to both maintain high eccentricities and to move to short enough orbital periods (1-20 days) for extreme tidal heating to occur. Secular resonance and secular orbital perturbations may support moderate tidal heating at a low equilibrium eccentricity. At orbital periods below 10-30 days, with eccentricities from 0.01 to 0.1, tidal heat may greatly exceed radiogenic heat production. It is unlikely to exceed insolation, except when orbiting very low luminosity hosts, and thus will have limited surface temperature expression. Observations of such bodies many not be able to detect tidal surface enhancements given a few percent uncertainty in albedo, except on the nightside of spin synchronous airless objects. Otherwise detection may occur via spectral detection of hotspots or high volcanic gas concentrations including sulfur dioxide and hydrogen sulfide. The most extreme cases may be able to produce magma oceans, or magma slush mantles with up to 40-60% melt fractions. Tides may alter the habitable zones for smaller red dwarf stars, but are generally detrimental. Multiple viscoelastic models, including the Maxwell, Voigt-Kelvin, Standard Anelastic Solid, and Burgers rheologies are explored and applied to objects such as Io and the super-Earth planet GJ 876d. The complex valued Love number for the Burgers rheology is derived and found to be a useful improvement when modeling the low temperature behavior of tidal bodies, particularly during low eccentricity

  9. Incremental Theory of Intelligence Moderated the Relationship between Prior Achievement and School Engagement in Chinese High School Students.

    Science.gov (United States)

    Li, Ping; Zhou, Nan; Zhang, Yuchi; Xiong, Qing; Nie, Ruihong; Fang, Xiaoyi

    2017-01-01

    School engagement plays a prominent role in promoting academic accomplishments. In contrast to the relative wealth of research that examined the impact of students' school engagement on their academic achievement, considerably less research has investigated the effect of high school students' prior achievement on their school engagement. The present study examined the relationship between prior achievement and school engagement among Chinese high school students. Based on the Dweck's social-cognitive theory of motivation, we further examined the moderating effect of students' theories of intelligence (TOIs) on this relationship. A total of 4036 (2066 girls) students from five public high school enrolled in grades 10 reported their high school entrance exam achievement in Chinese, Math and English, school engagement, and TOIs. Results showed that (a) students' prior achievement predicted their behavioral, emotional, and cognitive engagement, respectively, and (b) the association between prior achievement and behavioral, emotional, and cognitive engagement is strong for students with an incremental theory but not for those with an entity theory in the emotional and cognitive engagement. These findings suggest that prior achievement and incremental theory were implicated in relation to adolescents' school engagement. Implications and future research directions were discussed.

  10. Incremental Theory of Intelligence Moderated the Relationship between Prior Achievement and School Engagement in Chinese High School Students

    Directory of Open Access Journals (Sweden)

    Ping Li

    2017-09-01

    Full Text Available School engagement plays a prominent role in promoting academic accomplishments. In contrast to the relative wealth of research that examined the impact of students’ school engagement on their academic achievement, considerably less research has investigated the effect of high school students’ prior achievement on their school engagement. The present study examined the relationship between prior achievement and school engagement among Chinese high school students. Based on the Dweck’s social-cognitive theory of motivation, we further examined the moderating effect of students’ theories of intelligence (TOIs on this relationship. A total of 4036 (2066 girls students from five public high school enrolled in grades 10 reported their high school entrance exam achievement in Chinese, Math and English, school engagement, and TOIs. Results showed that (a students’ prior achievement predicted their behavioral, emotional, and cognitive engagement, respectively, and (b the association between prior achievement and behavioral, emotional, and cognitive engagement is strong for students with an incremental theory but not for those with an entity theory in the emotional and cognitive engagement. These findings suggest that prior achievement and incremental theory were implicated in relation to adolescents’ school engagement. Implications and future research directions were discussed.

  11. The High-Potential Fast-Flying Achiever: Themes from the English Language Literature 1976-1995.

    Science.gov (United States)

    Altman, Yochanan

    1997-01-01

    Review of business management literature from the United States, United Kingdom, and Canada identified the following: the images of high flyer, fast track, and high achiever; the meaning of success; emphasis on performance; corporate rites of passage; and opportunities for women to be high flyers. (SK)

  12. Raising the stakes: How students' motivation for mathematics associates with high- and low-stakes test achievement.

    Science.gov (United States)

    Simzar, Rahila M; Martinez, Marcela; Rutherford, Teomara; Domina, Thurston; Conley, AnneMarie M

    2015-04-01

    This study uses data from an urban school district to examine the relation between students' motivational beliefs about mathematics and high- versus low-stakes math test performance. We use ordinary least squares and quantile regression analyses and find that the association between students' motivation and test performance differs based on the stakes of the exam. Students' math self-efficacy and performance avoidance goal orientation were the strongest predictors for both exams; however, students' math self-efficacy was more strongly related to achievement on the low-stakes exam. Students' motivational beliefs had a stronger association at the low-stakes exam proficiency cutoff than they did at the high-stakes passing cutoff. Lastly, the negative association between performance avoidance goals and high-stakes performance showed a decreasing trend across the achievement distribution, suggesting that performance avoidance goals are more detrimental for lower achieving students. These findings help parse out the ways motivation influences achievement under different stakes.

  13. What’s Past is Prologue: Relations Between Early Mathematics Knowledge and High School Achievement

    OpenAIRE

    Watts, Tyler W.; Duncan, Greg J.; Siegler, Robert S.; Davis-Kean, Pamela E.

    2014-01-01

    © 2014 AERA. Although previous research has established the association between early-grade mathematics knowledge and later mathematics achievement, few studies have measured mathematical skills prior to school entry, and few have investigated the predictive power of early gains in mathematics ability. The current paper relates mathematical skills measured at 54 months to adolescent mathematics achievement using multisite longitudinal data. We find that preschool mathematics ability predicts ...

  14. Introduced Terrestrial Species (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — These data represent predicted future potential distributions of terrestrial plants, animals, and pathogens non-native to the Middle-Atlantic region. These data are...

  15. Family socioeconomic status, family health, and changes in students' math achievement across high school: A mediational model.

    Science.gov (United States)

    Barr, Ashley Brooke

    2015-09-01

    In response to recent calls to integrate understandings of socioeconomic disparities in health with understandings of socioeconomic disparities in academic achievement, this study tested a mediational model whereby family socioeconomic status predicted gains in academic achievement across high school through its impact on both student and parent health. Data on over 8000 high school students in the U.S. were obtained from wave 1 (2009-2010) and wave 2 (2012) of the High School Longitudinal Study of 2009 (HSLS:09), and structural equation modeling with latent difference scores was used to determine the role of family health problems in mediating the well-established link between family SES and gains in academic achievement. Using both static and dynamic indicators of family SES, support was found for this mediational model. Higher family SES in 9th grade reduced the probability of students and their parents experiencing a serious health problem in high school, thereby promoting growth in academic achievement. In addition, parent and student health problems mediated the effect of changes in family SES across high school on math achievement gains. Results emphasize the importance of considering the dynamic nature of SES and that both student and parent health should be considered in understanding SES-related disparities in academic achievement. This relational process provides new mechanisms for understanding the intergenerational transmission of socioeconomic status and the status attainment process more broadly. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Terrestrial ecosystems and biodiversity

    CSIR Research Space (South Africa)

    Davis-Reddy, Claire

    2017-10-01

    Full Text Available Ecoregions Terrestrial Biomes Protected Areas Climate Risk and Vulnerability: A Handbook for Southern Africa | 75 7.2. Non-climatic drivers of ecosystem change 7.2.1. Land-use change, habitat loss and fragmentation Land-use change and landscape... concentrations of endemic plant and animal species, but these mainly occur in areas that are most threatened by human activity. Diverse terrestrial ecosystems in the region include tropical and sub-tropical forests, deserts, savannas, grasslands, mangroves...

  17. A simple approach for a spatial terrestrial exposure assessment of the insecticide fenoxycarb, based on a high-resolution landscape analysis.

    Science.gov (United States)

    Thomas, Kai; Resseler, Herbert; Spatz, Robert; Hendley, Paul; Sweeney, Paul; Urban, Martin; Kubiak, Roland

    2016-11-01

    The objective was to refine the standard regulatory exposure scenario used in plant protection product authorisations by developing a more realistic landscape-related GIS-based exposure assessment for terrestrial non-target arthropods. We quantified the proportion of adjacent off-target area in agricultural landscapes potentially exposed to insecticide drift from applications of the active substance fenoxycarb. High-resolution imagery, landscape classification and subsequent stepwise analysis of a whole landscape using drift and interception functions were applied to selected areas in representative fruit-producing regions in Germany. Even under worst-case assumptions regarding treated area, use rate and drift, less than 12% of the non-agricultural habitat area would potentially be exposed to fenoxycarb drift above regulatory acceptable concentrations. Additionally, if the filtering effect of tall vegetation were taken into account, this number would decrease to 6.6%. Further refinements to landscape elements and application conditions indicate that less than 5% of the habitat area might be exposed above regulatory acceptable concentrations, meaning that 95% of the non-agricultural habitat area will be unimpacted (i.e. no unacceptable effects) and can serve as refuge for recolonisation. Approaches and tools are proposed for standardisable and transparent refinements in regulatory risk assessments on the landscape level. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  18. Factors associated with high probability of target blood pressure non-achievement in hypertensive patients

    Directory of Open Access Journals (Sweden)

    S. P. Zhemanyuk

    2017-12-01

    Full Text Available One of the topic issue of modern cardiology is factors of target blood pressure level non-achievement clarifying due to a better understanding how we can reduce cardiovascular complications. The aim of the study is to determine the factors of poor blood pressure control using the ambulatory blood pressure monitoring parameters and adenosine 5'-diphosphate-induced platelet aggregation parameters in patients with arterial hypertension. Material and methods. The study involved 153 patients with essential hypertension (EH stage II, II degree. The ambulatory blood pressure monitoring (ABPM was performed in patients during at least two of first-line antihypertensive drugs in optimal daily doses usage by the ABPM bifunctional device (Incart, S.-P., R.F.. Platelet aggregation was carried out using light transmittance aggregation by optical analyzer (Solar, R.B. with adenosine 5'-diphosphate (Sigma-Aldrich at final concentration of 10.0 × 10-6 mol / L. The first group were inadequately controlled essential hypertensive individuals with high systolic or/and diastolic BP level according to the ABPM results, and the second one were patients with adequately controlled EH. Groups of patients were comparable in age (60.39 ± 10.74 years vs. 62.80 ± 9.63; p = 0.181, respectively. In the group of EH patients who reached the target level of blood pressure, women predominated (60% vs. 39.81%; p = 0.021, respectively. We used the binary logistic regression analysis to determine the predictors of target blood pressure level poor reaching using ABPM and platelet aggregation parameters. Results According to the univariate logistic regression analysis, the dependent factors influencing the target blood pressure level poor reaching are the average diurnal diastolic blood pressure (DBP (OR = 44.8; diurnal variability of systolic blood pressure (SBP (OR = 4.4; square index of hypertension for diurnal periods SBP (OR = 318.9; square index of hypertension for diurnal

  19. Academic Achievement and Risk Factors for Adolescents with Attention-Deficit Hyperactivity Disorder in Middle School and Early High School.

    Science.gov (United States)

    Zendarski, Nardia; Sciberras, Emma; Mensah, Fiona; Hiscock, Harriet

    Examine academic achievement of students with attention-deficit hyperactivity disorder (ADHD) during the early high school period and identify potentially modifiable risk factors for low achievement. Data were collected through surveys (adolescent, parent, and teacher) and direct assessment of Australian adolescents (12-15 yr; n = 130) with ADHD in early high school (i.e., US middle and high school grades). Academic achievement outcomes were measured by linking to individual performance on the National Assessment Program-Literacy and Numeracy (NAPLAN) tests, direct assessment of reading and math, and teacher report of academic competence. Linear regression models examined associations between adolescent, parent/family, and school factors and NAPLAN domain scores. Students with ADHD had lower NAPLAN scores on all domains and fewer met minimum academic standards in comparison with state benchmarks. The poorest results were for persuasive writing. Poor achievement was associated with lower intelligence quotient across all academic domains. Adolescent inattention, bullying, poor family management, male sex, and attending a low socioeconomic status school were associated with lower achievement on specific domains. Students with ADHD are at increased academic risk during the middle school and early high school period. In addition to academic support, interventions targeting modifiable factors including inattention, bullying, and poor family management may improve academic achievement across this critical period.

  20. Influence of Strategy of Learning and Achievement Motivation of Learning Achievement Class VIII Students of State Junior High School in District Blitar

    Science.gov (United States)

    Ayundawati, Dyah; Setyosari, Punaji; Susilo, Herawati; Sihkabuden

    2016-01-01

    This study aims for know influence of problem-based learning strategies and achievement motivation on learning achievement. The method used in this research is quantitative method. The instrument used in this study is two fold instruments to measure moderator variable (achievement motivation) and instruments to measure the dependent variable (the…

  1. High-precision U-Pb geochronologic constraints on the Late Cretaceous terrestrial cyclostratigraphy and geomagnetic polarity from the Songliao Basin, Northeast China

    Science.gov (United States)

    Wang, Tiantian; Ramezani, Jahandar; Wang, Chengshan; Wu, Huaichun; He, Huaiyu; Bowring, Samuel A.

    2016-07-01

    The Cretaceous continental sedimentary records are essential to our understanding of how the terrestrial geologic and ecologic systems responded to past climate fluctuations under greenhouse conditions and our ability to forecast climate change in the future. The Songliao Basin of Northeast China preserves a near-complete, predominantly lacustrine, Cretaceous succession, with sedimentary cyclicity that has been tied to Milankocitch forcing of the climate. Over 900 meters of drill-core recovered from the Upper Cretaceous (Turonian to Campanian) of the Songliao Basin has provided a unique opportunity for detailed analyses of its depositional and paleoenvironmental records through integrated and high-resolution cyclostratigraphic, magnetostratigraphic and geochronologic investigations. Here we report high-precision U-Pb zircon dates (CA-ID-TIMS method) from four interbedded bentonites from the drill-core that offer substantial improvements in accuracy, and a ten-fold enhancement in precision, compared to the previous U-Pb SIMS geochronology, and allow a critical evaluation of the Songliao astrochronological time scale. The results indicate appreciable deviations of the astrochronologic model from the absolute radioisotope geochronology, which more likely reflect cyclostratigraphic tuning inaccuracies and omitted cycles due to depositional hiatuses, rather than suspected limitations of astronomical models applied to distant geologic time. Age interpolation based on our new high-resolution geochronologic framework and the calibrated cyclostratigraphy places the end of the Cretaceous Normal Superchon (C34n-C33r chron boundary) in the Songliao Basin at 83.07 ± 0.15 Ma. This date also serves as a new and improved estimate for the global Santonian-Campanian stage boundary.

  2. Achievement Emotions as Predictors of High School Science Success Among African-American and European American Students

    Science.gov (United States)

    Bowe, Marilyn Louise Simmons

    The literature includes few studies of the interrelations of achievement goals and achievement emotions with respect to minority students and science achievement. The objective of this study was to test the control-value theory (CVT) of achievement emotions to determine if the eight discrete achievement emotions would be predictive of test scores on the High School Graduation Test (GHSGT)-Science for African-American compared to European-American science students. Convenience cluster sampling was employed to select 160 students who were all juniors in the same public high school at the time that they took the GHSGT-Science. The central research question for this study aimed to uncover whether any of the eight achievement emotions identified in CVT would contribute significantly to the predictability of science achievement as measured by GHSGT-Science scores. Data were collected using a nonexperimental, cross sectional design survey. Data were analyzed using a hierarchal, forced entry, multiple regression analysis. Key results indicated that the eight achievement emotions were predictive of GHSGT-Science score outcomes. Positive social change at the individual level could reflect a boost in confidence for African American science students and help decrease the achievement gap in science, technology, engineering, and mathematics (STEM) endeavors between European Americans and African-American students. Educators may consider the importance of achievement emotions in science outcomes by including social emotional learning (SEL) as a part of the regular science curriculum. Future researchers should repeat the study in a school district where the population is available to support the desired cluster sample of equal parts European Americans to African Americans and male to female students.

  3. Markets, voucher subsidies and free nets combine to achieve high bed net coverage in rural Tanzania

    Directory of Open Access Journals (Sweden)

    Gerrets Rene PM

    2008-06-01

    Full Text Available Abstract Background Tanzania has a well-developed network of commercial ITN retailers. In 2004, the government introduced a voucher subsidy for pregnant women and, in mid 2005, helped distribute free nets to under-fives in small number of districts, including Rufiji on the southern coast, during a child health campaign. Contributions of these multiple insecticide-treated net delivery strategies existing at the same time and place to coverage in a poor rural community were assessed. Methods Cross-sectional household survey in 6,331 members of randomly selected 1,752 households of 31 rural villages of Demographic Surveillance System in Rufiji district, Southern Tanzania was conducted in 2006. A questionnaire was administered to every consenting respondent about net use, treatment status and delivery mechanism. Findings Net use was 62.7% overall, 87.2% amongst infants (0 to1 year, 81.8% amongst young children (>1 to 5 years, 54.5% amongst older children (6 to 15 years and 59.6% amongst adults (>15 years. 30.2% of all nets had been treated six months prior to interview. The biggest source of nets used by infants was purchase from the private sector with a voucher subsidy (41.8%. Half of nets used by young children (50.0% and over a third of those used by older children (37.2% were obtained free of charge through the vaccination campaign. The largest source of nets amongst the population overall was commercial purchase (45.1% use and was the primary means for protecting adults (60.2% use. All delivery mechanisms, especially sale of nets at full market price, under-served the poorest but no difference in equity was observed between voucher-subsidized and freely distributed nets. Conclusion All three delivery strategies enabled a poor rural community to achieve net coverage high enough to yield both personal and community level protection for the entire population. Each of them reached their relevant target group and free nets only temporarily

  4. The effect of authentic leadership, organizational justice, and achievement motivation on teachers' performance in vocational high school seventeen Temanggung

    Science.gov (United States)

    Sugi, Slamet, Achmad; Martono, S.

    2018-03-01

    Teachers' performance in Temanggung in 2016 did not show maximal result. It was shown from many indicators. The low score of UN, UKG and PKB result. Individual performance was different. Achievement motivation could be seen through their attitude and behavior performances. The purpose of this research is to know the effect of authentic leadership, organizational justice, and achievement motivation on teachers' performance. The objects of this research are authentic leadership, organizational justice, achievement motivation and teachers' performance in Vocational High School Seventeen in Temanggung. The research method used is quantitative. Data collection was done by questioners. Then, the data were analyzed by using Path SPSS 16. The result of this research showed that authentic leadership, organizational justice, achievement motivation had significant effect on teachers' performance in Vocational High School Seventeen in Temanggung.

  5. Students' attitude to homework: how is homework perceived by high-achieving students and those with learning disabilities

    OpenAIRE

    Trobec, Nika

    2013-01-01

    Homework assignments have many positive educational effects, which are achieved only when they are regularly performed and completed. While doing homework, students are under the influence of various external and internal factors that affect its utility. Many of them experience homework-related problems in one or more areas which are described in theoretical part. Aim of the empirical survey was to do a research on homework practices of students with learning disabilities and high achieving s...

  6. The Influence of the Antecedent Variable on the Teachers' Performance through Achievement Motivation in Senior High School

    Science.gov (United States)

    Dewi, Erni R.; Bundu, Patta; Tahmir, Suradi

    2016-01-01

    This study aims at analysing whether the antecedent variable directly affects the performance of the high school teachers or not. In addition, this research strives to find out whether the antecedent variable indirectly affects the teachers' performance through the achievement motivation of the high school teachers. It was a quantitative research…

  7. High School Mathematics Teachers' Levels of Achieving Technology Integration and In-Class Reflections: The Case of Mathematica

    Science.gov (United States)

    Ardiç, Mehmet Alper; Isleyen, Tevfik

    2017-01-01

    The purpose of this study is to determine the levels of high school mathematics teachers in achieving mathematics instruction via computer algebra systems and the reflections of these practices in the classroom. Three high school mathematics teachers employed at different types of school participated in the study. In the beginning of this…

  8. The Grasshopper and the Ant: Motivational Responses of Low-Achieving Students to High-Stakes Testing.

    Science.gov (United States)

    Roderick, Melissa; Engel, Mimi

    2001-01-01

    Examined the responses of 102 low achieving sixth and eighth graders to Chicago's highly publicized efforts to end social promotion. Students generally described increased work efforts, and students with high levels of work effort generally had greater than average learning gains and positive outcomes in terms of promotion. About one-third of…

  9. The Relationship of Mental Pressure with Optimism and Academic Achievement Motivation among Second Grade Male High School Students

    Science.gov (United States)

    Sarouni, Ali Sedigh; Jenaabadi, Hossein; Pourghaz, Abdulwahab

    2016-01-01

    The present study aimed to examine the relationship of mental pressure with optimism and academic achievement motivation among second grade second period male high school students. This study followed a descriptive-correlational method. The sample included 200 second grade second period male high school students in Sooran. Data collection tools in…

  10. Case Studies of Factors Affecting the Motivation of Musical High Achievers to Learn Music in Hong Kong

    Science.gov (United States)

    Leung, Bo Wah; McPherson, Gary E.

    2011-01-01

    This article reports on the personal beliefs and attitudes of highly motivated Hong Kong school-age subjects who studied music. A total of 24 participants who demonstrated high achievement and interest in learning music were interviewed. Content analysis of the interview data was performed to elucidate four topics: background information about the…

  11. Gender Differences in Self-Concept, Locus of Control, and Goal Orientation in Mexican High-Achieving Students

    Science.gov (United States)

    Valdés-Cuervo, Angel Alberto; Sánchez Escobedo, Pedro Antonio; Valadez-Sierra, María Dolores

    2015-01-01

    The study compares self-concept, locus of control, and goal orientation characteristics of male and female Mexican high school high-achieving students. Three scales were administered to 220 students; 106 (49%) were males and 114 (51%) females. By means of a discriminant analysis, both groups were compared in relation to the variables such as…

  12. Effects of Intradistrict School Mobility and High Student Turnover Rates on Early Reading Achievement

    Science.gov (United States)

    LeBoeuf, Whitney A.; Fantuzzo, John W.

    2018-01-01

    The primary aim of this study was to assess the relations between concurrent, cumulative, and contextual intradistrict school mobility and early reading achievement. Longitudinal administrative school records were used for an entire cohort of students in a large urban district from first through third grade. Findings indicated that students with a…

  13. What's Past Is Prologue: Relations between Early Mathematics Knowledge and High School Achievement

    Science.gov (United States)

    Watts, Tyler W.; Duncan, Greg J.; Siegler, Robert S.; Davis-Kean, Pamela E.

    2014-01-01

    Although previous research has established the association between early-grade mathematics knowledge and later mathematics achievement, few studies have measured mathematical skills prior to school entry, and few have investigated the predictive power of early gains in mathematics ability. The current paper relates mathematical skills measured at…

  14. The Relationship of Grade Span in 9th Grade to Math Achievement in High School

    Science.gov (United States)

    West, John; Miller, Mary Lou; Myers, Jim; Norton, Timothy

    2015-01-01

    Purpose, Scope, and Method of Study: The purpose of this study was to determine if a correlation exists between grade span for ninth grade and gains in math achievement test scores in 10th grade and 12th grade. A quantitative, longitudinal, correlational research design was employed to investigate the research questions. The population was high…

  15. Unequal Academic Achievement in High School: The Mediating Roles of Concerted Cultivation and Close Friends

    Science.gov (United States)

    Carolan, Brian V.

    2016-01-01

    Building from the classic Wisconsin model of status attainment, this study examines whether a specific style of parenting, concerted cultivation, and a close friend's school-related attitudes and behaviors mediate the relationship between a family's socioeconomic status and their child's academic achievement in the United States. Using a recursive…

  16. The Contribution of Cultural Capital to Students' Mathematics Achievement in Medium and High Socioeconomic Gradient Economies

    Science.gov (United States)

    Tan, Cheng Yong

    2015-01-01

    The present study addresses the issue of how different forms of cultural capital may influence children's mathematics achievement in economies with different socioeconomic gradients. Data from 73,178 parent-child dyads from 10 economies with different socioeconomic gradients who participated in the Programme for International Student Assessment…

  17. Academic Achievement of High School Students in Relation to Their Anxiety, Emotional Maturity and Social Maturity

    Science.gov (United States)

    Puar, Surjit Singh

    2013-01-01

    The present study has been designed to investigate the non-cognitive variables like anxiety, emotional maturity and social maturity and their relationship with academic achievement and also to see the locale-wise differences on the basis of their anxiety, emotional maturity and social maturity. The study was conducted over a sample of 400 (200…

  18. Impacts of Comprehensive Reading Instruction on Diverse Outcomes of Low- and High-Achieving Readers

    Science.gov (United States)

    Guthrie, John T.; McRae, Angela; Coddington, Cassandra S.; Klauda, Susan Lutz; Wigfield, Allan; Barbosa, Pedro

    2009-01-01

    Low-achieving readers in Grade 5 often lack comprehension strategies, domain knowledge, word recognition skills, fluency, and motivation to read. Students with such multiple reading needs seem likely to benefit from instruction that supports each of these reading processes. The authors tested this expectation experimentally by comparing the…

  19. Faculty Sense of Academic Optimism and Its Relationship to Students' Achievement in Well Performing High Schools

    Science.gov (United States)

    Cromartie, Michael Tyrone

    2013-01-01

    The aim of this study was to determine the organizational characteristics and behaviors that contribute to sustaining a culture of academic optimism as a mechanism of student achievement. While there is a developing research base identifying both the individual elements of academic optimism as well as the academic optimism construct itself as…

  20. Mathematically Gifted Students and High Achievement: The Role of Motivation and Classroom Structure

    Science.gov (United States)

    Lüftenegger, Marko; Kollmayer, Marlene; Bergsmann, Evelyn; Jöstl, Gregor; Spiel, Christiane; Schober, Barbara

    2015-01-01

    One of the most intriguing questions for those who study intellectually gifted students is why some of them reach peak performances at school and others don't. Moderator theories of giftedness assume that domain-specific gifts are transformed into achievement in a process influenced by non-cognitive and environmental variables. Thus, the current…

  1. The Influence of Mathematics Anxiety in Middle and High School Students Math Achievement

    Science.gov (United States)

    Al Mutawah, Masooma Ali

    2015-01-01

    Math anxiety has been the focus of much psychological and educational research in the past few years, there are many international studies showing that mathematics anxiety is an influence on student's achievements in school, but little research has been done about this issue in Bahrain. Bahrain is a country in the Arabian Gulf region, its economic…

  2. Gender Gap Linked to Differential Socialization for High-Achieving Senior Mathematics Students.

    Science.gov (United States)

    Campbell, James R.; Beaudry, Jeffrey S.

    1998-01-01

    Examined whether 11th-grade girls and boys enrolled in advanced mathematics courses nationwide were socialized in similar ways, using Campbell's differential socialization paradigm. Results uncovered a gender gap favoring boys. Self-imposed pressure and persistence had important direct effects on achievement. Self-concept had important direct…

  3. Teacher Commitment and Its Effects on Student Achievement in American High Schools

    Science.gov (United States)

    Park, Insim

    2005-01-01

    This study explored the effects of teacher commitment on student achievement. Three teacher commitment dimensions of organizational, professional, and student commitment were derived. The three-dimensional teacher commitment measurement model was tested by a confirmatory factor analysis. Then, the relationships among individual and organizational…

  4. Measurement Axis Searching Model for Terrestrial Laser Scans Registration

    Directory of Open Access Journals (Sweden)

    Shaoxing Hu

    2016-01-01

    Full Text Available Nowadays, terrestrial Lidar scans can cover rather a large area; the point densities are strongly varied because of the line-of-sight measurement principle in potential overlaps with scans taken from different viewpoints. Most of the traditional methods focus on registration algorithm and ignore searching model. Sometimes the traditional methods are directly used to align two point clouds; a large critically unsolved problem of the large biases will be created in areas distant from the overlaps while the local overlaps are often aligned well. So a novel measurement axis searching model (MASM has been proposed in this paper. The method includes four steps: (1 the principal axis fitting, (2 the measurement axis generation, (3 low-high-precision search, and (4 result generation. The principal axis gives an orientation to the point cloud; the search scope is limited by the measurement axis. The point cloud orientation can be adjusted gradually until the achievement of the global optimum using low- and high-precision search. We perform some experiments with simulated point clouds and real terrestrial laser scans. The results of simulated point clouds have shown the processing steps of our method, and the results of real terrestrial laser scans have shown the sensitivity of the approach with respect to the indoor and outdoor scenes.

  5. Terrestrial Analogs to Mars

    Science.gov (United States)

    Farr, T. G.; Arcone, S.; Arvidson, R. W.; Baker, V.; Barlow, N. G.; Beaty, D.; Bell, M. S.; Blankenship, D. D.; Bridges, N.; Briggs, G.; Bulmer, M.; Carsey, F.; Clifford, S. M.; Craddock, R. A.; Dickerson, P. W.; Duxbury, N.; Galford, G. L.; Garvin, J.; Grant, J.; Green, J. R.; Gregg, T. K. P.; Guinness, E.; Hansen, V. L.; Hecht, M. H.; Holt, J.; Howard, A.; Keszthelyi, L. P.; Lee, P.; Lanagan, P. D.; Lentz, R. C. F.; Leverington, D. W.; Marinangeli, L.; Moersch, J. E.; Morris-Smith, P. A.; Mouginis-Mark, P.; Olhoeft, G. R.; Ori, G. G.; Paillou, P.; Reilly, J. F., II; Rice, J. W., Jr.; Robinson, C. A.; Sheridan, M.; Snook, K.; Thomson, B. J.; Watson, K.; Williams, K.; Yoshikawa, K.

    2002-08-01

    It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing. These studies include field workshops, characterization of terrestrial analog sites, instrument tests, laboratory measurements (including analysis of Martian meteorites), and computer and laboratory modeling. The combination of all these activities allows scientists to constrain the processes operating in specific terrestrial environments and extrapolate how similar processes could affect Mars. The Terrestrial Analogs for Mars Community Panel has considered the following two key questions: (1) How do terrestrial analog studies tie in to the Mars Exploration Payload Assessment Group science questions about life, past climate, and geologic evolution of Mars, and (2) How can future instrumentation be used to address these questions. The panel has considered the issues of data collection, value of field workshops, data archiving, laboratory measurements and modeling, human exploration issues, association with other areas of solar system exploration, and education and public outreach activities.

  6. Implicit motive profile of treatment-seeking opiate users: high affiliation and low achievement.

    Science.gov (United States)

    Bársonya, Katalin; Martos, Tamás; Ehmann, Bea; Balázs, Hedvig; Demetrovics, Zsolt

    2013-01-01

    Research on basic human motives (achievement, affiliation, and power) encoded at the emotional level recently returned to the forefront of scientific research. To date, there are only a few studies on the pattern of implicit motives of substance users, so the present study examined opiate users participating in methadone maintenance treatment (N = 80) along these dimensions, comparing them to 40 non-substance users. Participants were asked to create stories on the basis of the pictures of the Thematic Apperception Test. The stories were analyzed using the content analysis method of David Winter (1991). Like other substance user groups, opiate-dependent persons used less achievement and more affiliation notions in creating stories, while there was no significant difference between the two groups concerning power notions. The results proved to be independent of the presence of anxiety and depression symptoms, despite substance users reporting higher levels of these, and suggest that motivational factors are worth considering in treatment planning.

  7. Behavior problems at ages 6 and 11 and high school academic achievement: longitudinal latent variable modeling.

    Science.gov (United States)

    Breslau, Naomi; Breslau, Joshua; Miller, Elizabeth; Raykov, Tenko

    2011-02-28

    Previous studies documented long-run effects of behavior problems at the start of school on academic achievement. However, these studies did not examine whether the observed effects of early behavior problems are explained by more proximate behavior problems, given the tendency of children's behavior problems to persist. Latent variable modeling was applied to estimate the effects of behavior problems at ages 6 and 11 on academic achievement at age 17, using data from a longitudinal study (n=823). Behavior problems at ages 6 and 11, each stage independently of the other, predicted lower math and reading test scores at age 17, controlling for intelligence quotient (IQ), birth weight, maternal characteristics, family and community environment, and taking into account behavior problems at age 17. Behavior problems at the start of school, independent of later behavior problems, exert lingering effects on achievement by impeding the acquisition of cognitive skills that are the foundation for later academic progress. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  8. Birds achieve high robustness in uneven terrain through active control of landing conditions.

    Science.gov (United States)

    Birn-Jeffery, Aleksandra V; Daley, Monica A

    2012-06-15

    We understand little about how animals adjust locomotor behaviour to negotiate uneven terrain. The mechanical demands and constraints of such behaviours likely differ from uniform terrain locomotion. Here we investigated how common pheasants negotiate visible obstacles with heights from 10 to 50% of leg length. Our goal was to determine the neuro-mechanical strategies used to achieve robust stability, and address whether strategies vary with obstacle height. We found that control of landing conditions was crucial for minimising fluctuations in stance leg loading and work in uneven terrain. Variation in touchdown leg angle (θ(TD)) was correlated with the orientation of ground force during stance, and the angle between the leg and body velocity vector at touchdown (β(TD)) was correlated with net limb work. Pheasants actively targeted obstacles to control body velocity and leg posture at touchdown to achieve nearly steady dynamics on the obstacle step. In the approach step to an obstacle, the birds produced net positive limb work to launch themselves upward. On the obstacle, body dynamics were similar to uniform terrain. Pheasants also increased swing leg retraction velocity during obstacle negotiation, which we suggest is an active strategy to minimise fluctuations in peak force and leg posture in uneven terrain. Thus, pheasants appear to achieve robustly stable locomotion through a combination of path planning using visual feedback and active adjustment of leg swing dynamics to control landing conditions. We suggest that strategies for robust stability are context specific, depending on the quality of sensory feedback available, especially visual input.

  9. Computer simulations in the high school: students' cognitive stages, science process skills and academic achievement in microbiology

    Science.gov (United States)

    Huppert, J.; Michal Lomask, S.; Lazarowitz, R.

    2002-08-01

    Computer-assisted learning, including simulated experiments, has great potential to address the problem solving process which is a complex activity. It requires a highly structured approach in order to understand the use of simulations as an instructional device. This study is based on a computer simulation program, 'The Growth Curve of Microorganisms', which required tenth grade biology students to use problem solving skills whilst simultaneously manipulating three independent variables in one simulated experiment. The aims were to investigate the computer simulation's impact on students' academic achievement and on their mastery of science process skills in relation to their cognitive stages. The results indicate that the concrete and transition operational students in the experimental group achieved significantly higher academic achievement than their counterparts in the control group. The higher the cognitive operational stage, the higher students' achievement was, except in the control group where students in the concrete and transition operational stages did not differ. Girls achieved equally with the boys in the experimental group. Students' academic achievement may indicate the potential impact a computer simulation program can have, enabling students with low reasoning abilities to cope successfully with learning concepts and principles in science which require high cognitive skills.

  10. 2500 high-quality genomes reveal that the biogeochemical cycles of C, N, S and H are cross-linked by metabolic handoffs in the terrestrial subsurface

    Science.gov (United States)

    Anantharaman, K.; Brown, C. T.; Hug, L. A.; Sharon, I.; Castelle, C. J.; Shelton, A.; Bonet, B.; Probst, A. J.; Thomas, B. C.; Singh, A.; Wilkins, M.; Williams, K. H.; Tringe, S. G.; Beller, H. R.; Brodie, E.; Hubbard, S. S.; Banfield, J. F.

    2015-12-01

    Microorganisms drive the transformations of carbon compounds in the terrestrial subsurface, a key reservoir of carbon on earth, and impact other linked biogeochemical cycles. Our current knowledge of the microbial ecology in this environment is primarily based on 16S rRNA gene sequences that paint a biased picture of microbial community composition and provide no reliable information on microbial metabolism. Consequently, little is known about the identity and metabolic roles of the uncultivated microbial majority in the subsurface. In turn, this lack of understanding of the microbial processes that impact the turnover of carbon in the subsurface has restricted the scope and ability of biogeochemical models to capture key aspects of the carbon cycle. In this study, we used a culture-independent, genome-resolved metagenomic approach to decipher the metabolic capabilities of microorganisms in an aquifer adjacent to the Colorado River, near Rifle, CO, USA. We sequenced groundwater and sediment samples collected across fifteen different geochemical regimes. Sequence assembly, binning and manual curation resulted in the recovery of 2,542 high-quality genomes, 27 of which are complete. These genomes represent 1,300 non-redundant organisms comprising both abundant and rare community members. Phylogenetic analyses involving ribosomal proteins and 16S rRNA genes revealed the presence of up to 34 new phyla that were hitherto unknown. Less than 11% of all genomes belonged to the 4 most commonly represented phyla that constitute 93% of all currently available genomes. Genome-specific analyses of metabolic potential revealed the co-occurrence of important functional traits such as carbon fixation, nitrogen fixation and use of electron donors and electron acceptors. Finally, we predict that multiple organisms are often required to complete redox pathways through a complex network of metabolic handoffs that extensively cross-link subsurface biogeochemical cycles.

  11. The Relationship between Family Functioning and Academic Achievement in Female High School Students of Isfahan, Iran, in 2013-2014.

    Science.gov (United States)

    Rezaei-Dehaghani, Abdollah; Keshvari, Mahrokh; Paki, Somayeh

    2018-01-01

    Nowadays, the most important problem of the educational system is the vast spread of school failure. Therefore, detection of the factors leading to or preventing students' academic achievement is of utmost importance. Family function is considered to be a critical component of academic success. This study aimed to investigate the relationship between family functioning and academic achievement in high school female students in Isfahan. This descriptive correlational study was conducted through random sampling among 237 female high school students in Isfahan during school year 2013-2014. Data were collected by participants' personal characteristics and Bloom family function questionnaires. To analyze the data, descriptive statistics (mean and standard deviation) and inferential statistics (Pearson correlation and linear regression analysis) were adopted and computed using SPSS software. The results showed a significant correlation between family function (except lack of independence) and students' academic achievement ( p family function dimensions, expressiveness ( β = 0.235, p family socialization ( β = 0.219, p = 0.001), and cohesion ( β = 0.211, p = 0.001) were more reliable predictors of academic achievement. The results of this study showed that students' academic achievement is highly correlated with the performance of their families. Therefore, to improve students' educational status in cultural and educational programs, which are specified for them, family function centered plans should be at the heart of attention.

  12. The relationship between family functioning and academic achievement in female high school students of Isfahan, Iran, in 2013–2014

    Directory of Open Access Journals (Sweden)

    Abdollah Rezaei-Dehaghani

    2018-01-01

    Full Text Available Background: Nowadays, the most important problem of the educational system is the vast spread of school failure. Therefore, detection of the factors leading to or preventing students' academic achievement is of utmost importance. Family function is considered to be a critical component of academic success. This study aimed to investigate the relationship between family functioning and academic achievement in high school female students in Isfahan. Materials and Methods: This descriptive correlational study was conducted through random sampling among 237 female high school students in Isfahan during school year 2013-2014. Data were collected by participants' personal characteristics and Bloom family function questionnaires. To analyze the data, descriptive statistics (mean and standard deviation and inferential statistics (Pearson correlation and linear regression analysis were adopted and computed using SPSS software. Results: The results showed a significant correlation between family function (except lack of independence and students' academic achievement (p < 0.05. Further, among family function dimensions, expressiveness (β = 0.235, p < 0.001, family socialization (β = 0.219, p = 0.001, and cohesion (β = 0.211, p = 0.001 were more reliable predictors of academic achievement. Conclusions: The results of this study showed that students' academic achievement is highly correlated with the performance of their families. Therefore, to improve students' educational status in cultural and educational programs, which are specified for them, family function centered plans should be at the heart of attention.

  13. Association between scores in high school, aptitude and achievement exams and early performance in health science college

    Directory of Open Access Journals (Sweden)

    Al-Alwan Ibrahim

    2009-01-01

    Full Text Available This retrospective study was carried out to assess the correlation between admi-ssion criteria to health science colleges, namely, final high school grade and Saudi National Apti-tude and Achievement exams, and early academic performance in these colleges. The study inclu-ded 91 male students studying in the two-year pre-professional program at the King Saud bin Abdulaziz University for Health Sciences (KSAU-HS, Riyadh, Saudi Arabia. Records of these students were used to extract relevant information and their academic performance (based on the grade point average achieved at the end of the first semester of the pre-professional program, which were analytically studied. Pearson correlation coefficient was used to assess the associa-tions between the different scores. SPSS statistical program (version 12.0 was used for data ana-lyses. We found a strong correlation between the academic performance and the Achievement Exam, Aptitude Exam and high school final grade, with Pearson Correlation Coefficients of 0.96, 0.93, 0.87, respectively. The Saudi National Achievement Exam showed the most significant correla-tion. Our results indicate that academic performance showed good correlation with the admission criteria used, namely final high school grade, Saudi National Aptitude and Achievement Exams.

  14. Terrestrial and extraterrestrial fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Heymann, D.; Jenneskens, L.W.; Jehlicka, J; Koper, C.; Vlietstra, E. [Rice Univ, Houston, TX (United States). Dept. of Earth Science

    2003-07-01

    This paper reviews reports of occurrences of fullerenes in circumstellar media, interstellar media, meteorites, interplanetary dust particles (IDPs), lunar rocks, hard terrestrial rocks from Shunga (Russia), Sudbury (Canada) and Mitov (Czech Republic), coal, terrestrial sediments from the Cretaceous-Tertiary-Boundary and Pennian-Triassic-Boundary, fulgurite, ink sticks, dinosaur eggs, and a tree char. The occurrences are discussed in the context of known and postulated processes of fullerene formation, including the suggestion that some natural fullerenes might have formed from biological (algal) remains.

  15. The Effect of a One to One Laptop Initiative on High School Math Achievement in a Suburban High School Environment

    Science.gov (United States)

    Heap, Bryan

    2018-01-01

    Technology continues to advance the pace of American education. Each year school districts across the country invest resources into computers, software, technology specialists, and staff development. The stated goal given to stakeholders is usually to increase student achievement, increase motivation, or to better prepare students for the future.…

  16. Short Circuits or Superconductors? Effects of Group Composition on High-Achieving Students' Science Assessment Performance.

    Science.gov (United States)

    Webb, Noreen M.; Nemer, Kariane Mari; Zuniga, Stephen

    2002-01-01

    Studied the effects of group ability composition (homogeneous versus heterogeneous) on group processes and outcomes for high-ability students completing science assessments. Results for 83 high ability students show the quality of group functioning serves as the strongest predictor of high-ability students' performance and explained much of the…

  17. Inquiry-Based Laboratory Activities in Electrochemistry: High School Students' Achievements and Attitudes

    Science.gov (United States)

    Sesen, Burcin Acar; Tarhan, Leman

    2013-01-01

    This study aimed to investigate the effects of inquiry-based laboratory activities on high school students' understanding of electrochemistry and attitudes towards chemistry and laboratory work. The participants were 62 high school students (average age 17 years) in an urban public high school in Turkey. Students were assigned to experimental (N =…

  18. Health-Related Behaviors and Academic Achievement Among High School Students - United States, 2015.

    Science.gov (United States)

    Rasberry, Catherine N; Tiu, Georgianne F; Kann, Laura; McManus, Tim; Michael, Shannon L; Merlo, Caitlin L; Lee, Sarah M; Bohm, Michele K; Annor, Francis; Ethier, Kathleen A

    2017-09-08

    Studies have shown links between educational outcomes such as letter grades, test scores, or other measures of academic achievement, and health-related behaviors (1-4). However, as reported in a 2013 systematic review, many of these studies have used samples that are not nationally representative, and quite a few studies are now at least 2 decades old (1). To update the relevant data, CDC analyzed results from the 2015 national Youth Risk Behavior Survey (YRBS), a biennial, cross-sectional, school-based survey measuring health-related behaviors among U.S. students in grades 9-12. Analyses assessed relationships between academic achievement (i.e., self-reported letter grades in school) and 30 health-related behaviors (categorized as dietary behaviors, physical activity, sedentary behaviors, substance use, sexual risk behaviors, violence-related behaviors, and suicide-related behaviors) that contribute to leading causes of morbidity and mortality among adolescents in the United States (5). Logistic regression models controlling for sex, race/ethnicity, and grade in school found that students who earned mostly A's, mostly B's, or mostly C's had statistically significantly higher prevalence estimates for most protective health-related behaviors and significantly lower prevalence estimates for most health-related risk behaviors than did students with mostly D's/F's. These findings highlight the link between health-related behaviors and education outcomes, suggesting that education and public health professionals can find their respective education and health improvement goals to be mutually beneficial. Education and public health professionals might benefit from collaborating to achieve both improved education and health outcomes for youths.

  19. IDENTITY AND TEMPORAL PERSPECTIVE OF ADOLESCENTS WITH HIGH ACHIEVEMENTS IN SCHOOL

    Directory of Open Access Journals (Sweden)

    Denitsa Alipieva

    2015-12-01

    Full Text Available The current article is an empirical approach reviewing the theories for the factors for formation of identity and self-conception in the adolescent. Under the theories for internal attribution and temporal perspective the study was conducted with teenagers between 11 and 18 years with different achievements. The aim is to show the relevance between the subjective affective involving and success in academic activity and realistic self-esteem that could enhance the abilities of students to create adequate plans and goals for future and mature self-conception

  20. Achieving high permeability and enhanced selectivity for Angstrom-scale separations using artificial water channel membranes.

    Science.gov (United States)

    Shen, Yue-Xiao; Song, Woochul C; Barden, D Ryan; Ren, Tingwei; Lang, Chao; Feroz, Hasin; Henderson, Codey B; Saboe, Patrick O; Tsai, Daniel; Yan, Hengjing; Butler, Peter J; Bazan, Guillermo C; Phillip, William A; Hickey, Robert J; Cremer, Paul S; Vashisth, Harish; Kumar, Manish

    2018-06-12

    Synthetic polymer membranes, critical to diverse energy-efficient separations, are subject to permeability-selectivity trade-offs that decrease their overall efficacy. These trade-offs are due to structural variations (e.g., broad pore size distributions) in both nonporous membranes used for Angstrom-scale separations and porous membranes used for nano to micron-scale separations. Biological membranes utilize well-defined Angstrom-scale pores to provide exceptional transport properties and can be used as inspiration to overcome this trade-off. Here, we present a comprehensive demonstration of such a bioinspired approach based on pillar[5]arene artificial water channels, resulting in artificial water channel-based block copolymer membranes. These membranes have a sharp selectivity profile with a molecular weight cutoff of ~ 500 Da, a size range challenging to achieve with current membranes, while achieving a large improvement in permeability (~65 L m -2  h -1  bar -1  compared with 4-7 L m -2  h -1  bar -1 ) over similarly rated commercial membranes.

  1. Biogeochemical Indicators in High- and Low-Arctic Marine and Terrestrial Avian Community Changes: Comparative Isotopic (13C, 15N, and 34S) Studies in Alaska and Greenland

    Science.gov (United States)

    Causey, D.; Bargmann, N. A.; Burnham, K. K.; Burnham, J. L.; Padula, V. M.; Johnson, J. A.; Welker, J. M.

    2011-12-01

    Understanding the complex dynamics of environmental change in northern latitudes is of paramount importance today, given documented rapid shifts in sea ice, plant phenology, temperatures, deglaciation, and habitat fidelity. This knowledge is particularly critical for Arctic avian communities, which are integral components by which biological teleconnections are maintained between the mid and northern latitudes. Furthermore, Arctic birds are fundamental to Native subsistence lifestyles and a focus for conservation activities. Avian communities of marine and terrestrial Arctic environments represent a broad spectrum of trophic levels, from herbivores (eg., geese Chen spp.), planktivores (eg., auklets Aethia spp.), and insectivores (eg., passerines: Wheatears Oenanthe spp., Longspurs Calcarius spp.), to predators of marine invertebrates (eg., eiders Somateria spp.), nearshore and offshore fish (eg., cormorants Phalacrocorax spp, puffins Fratercula spp.), even other bird species (eg., gulls Larus spp., falcons Peregrinus spp.). This diversity of trophic interconnections is an integral factor in the dynamics of Arctic ecosystem ecology, and they are key indicators for the strength and trajectories of change. We are especially interested in their feeding ecology, using stable isotope-diet relations to examine historical diets and to predict future feeding ecology by this range of species. Since 2009, we have been studying the foodweb ecology using stable isotopes (δ13C, δ15N, δ34S) of contemporaneous coastal and marine bird communities in High Arctic (Northwest Greenland) and Low Arctic (western Aleutian Islands, AK). We are quantifying the isotopic values of blood, organ tissues, and feathers, and have carried out comparisons between native and lipid-extracted samples. Although geographically distant, these communities comprise similar taxonomic and ecological congeners, including several species common to both (eg., Common Eider, Black-legged Kittiwake, Northern

  2. The effects of a science intervention program on the attitudes and achievement of high school girls in science

    Science.gov (United States)

    Steakley, Carrie Capers

    This study investigated the effects of a high school science intervention program that included hands-on activities, science-related career information and exposure, and real-world experiences on girls' attitudes and achievement in science. Eighty-four girls, 44 ninth-graders and 40 tenth-graders, and 105 parents participated in the study. Survey data was collected to assess the girls' attitudes toward science in seven distinct areas: social implications of science, normality of scientists, attitude toward scientific inquiry, adoption of scientific attitudes, enjoyment of science lessons, leisure interest in science, and career interest in science. Additional questionnaires were used to determine the extent of the girls' participation in sports and the attitudes of their parents toward science. The girls' cumulative science semester grade point averages since the seventh grade were used to assess academic science achievement. This study found no evidence that participation in the program improved the girls' attitudes or achievement in science. Parent attitudes and years of participation in sports were not accurate predictors of science achievement. Additionally, no significant relationship was detected between the girls' and their parents' perceptions of science. However, the study did suggest that extended participation in sports may positively affect science achievement for girls. This study holds implications for educational stakeholders who seek to implement intervention methods and programs that may improve student attitudes and achievement in science and attract more youth to future science-related careers.

  3. Sources of Global Academic Self-Efficacy in Academically High-Achieving Females before the Onset of Disordered Eating

    Science.gov (United States)

    Krafchek, Jennifer; Kronborg, Leonie

    2015-01-01

    There is limited research applying the four sources of self-efficacy (Bandura, 1997) to global academic self-efficacy. This qualitative study examined the sources of global academic self-efficacy in a sample of academically high-achieving females who developed disordered eating. Semistructured interviews were conducted with 14 participants to gain…

  4. The Effective Practices and Beliefs of School Principals in High Achieving Hispanic Majority Mid-Level Schools

    Science.gov (United States)

    Briseno, Johnny

    2010-01-01

    This qualitative phenomenological research study used narrative inquiry to investigate the effective practices and beliefs of 10 Texas principals in high achieving majority Hispanic mid-level schools. Participant interviews were analyzed using the Creswell (2007) six step method for analyzing phenomenological studies. Findings from this study…

  5. Do Socio-Motivational Relationships Predict Achievement Motivation in Adolescents with High and Low School Self-Concepts?

    Science.gov (United States)

    Bakadorova, Olga; Raufelder, Diana

    2016-01-01

    Considering the essential role that socio-motivational relationships at school play with respect to achievement motivation, this study examined the differences between students with a low school self-concept and students with a high school self-concept in a large sample of 7th and 8th grade students (N= 1088; M[subscript Age]= 13.7) in secondary…

  6. Practice Brief: Assessing Compensatory Strategies and Motivational Factors in High-Achieving Postsecondary Students with Attention Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Schaffer, Gary

    2013-01-01

    Research speculates that high-achieving college students with attention deficit/hyperactivity disorder (ADHD) may demonstrate a set of compensatory strategies and experience areas of difficulty and motivational factors that differ from the general ADHD populace. This Practice Brief used informal surveys with seven undergraduates with ADHD who had…

  7. Empowering the Middle: A High School Study Skills Program and Its Impact on Academic Achievement and Self-Efficacy

    Science.gov (United States)

    Simmons, Stephanie Yvette

    2017-01-01

    This study examined the impact of a self-regulatory skills course on the academic achievement and self-efficacy of 11th-grade students. The researcher compared intervention and control groups participants' pre- and posttest scores on the General Self-Efficacy Scale and the Learning and Study Skills Assessment Inventory-High School version. Scores…

  8. An Exploration of the Psychosocial Characteristics of High Achieving Students and Identified Gifted Students: Implications for Practice

    Science.gov (United States)

    Ritchotte, Jennifer A.; Suhr, Diana; Alfurayh, Naif F.; Graefe, Amy K.

    2016-01-01

    High achieving students or "bright children" are often denied access to gifted services because they do not meet "gifted" criteria. Although psychosocial factors play an integral role in academic success, and can be useful in providing a clearer picture of student need, they are seldom considered in the decision to identify a…

  9. The impact of high-stakes school admission exams on study achievements: quasi-experimental evidence from Slovakia

    Czech Academy of Sciences Publication Activity Database

    Federičová, Miroslava; Münich, Daniel

    2017-01-01

    Roč. 30, č. 4 (2017), s. 1069-1092 ISSN 0933-1433 R&D Projects: GA ČR(CZ) GBP402/12/G130 Institutional support: RVO:67985998 Keywords : high-stakes exams * students’ motivation * achievement Subject RIV: AH - Economics OBOR OECD: Applied Economics , Econometrics Impact factor: 1.136, year: 2016

  10. The impact of high-stakes school admission exams on study achievements: quasi-experimental evidence from Slovakia

    Czech Academy of Sciences Publication Activity Database

    Federičová, Miroslava; Münich, Daniel

    2017-01-01

    Roč. 30, č. 4 (2017), s. 1069-1092 ISSN 0933-1433 Institutional support: Progres-Q24 Keywords : high-stakes exams * students’ motivation * achievement Subject RIV: AH - Economics OBOR OECD: Applied Economics , Econometrics Impact factor: 1.136, year: 2016

  11. Predicting High School Graduation for Latino Males Using Expectancy Value Theory of Motivation and Tenth Grade Reading Achievement Scores

    Science.gov (United States)

    Knape, Erin Oakley

    2010-01-01

    National education data indicate that young men of color and students living in poverty are not experiencing the same academic success as their female, White, or higher socioeconomic status peers, as evidenced by low reading achievement levels and high dropout rates. Of particular concern is the underachievement of Latino males, who currently have…

  12. The Perceptions of Principals and Teachers Regarding Mental Health Providers' Impact on Student Achievement in High Poverty Schools

    Science.gov (United States)

    Perry, Teresa

    2012-01-01

    This study examined the perceptions of principals and teachers regarding mental health provider's impact on student achievement and behavior in high poverty schools using descriptive statistics, t-test, and two-way ANOVA. Respondents in this study shared similar views concerning principal and teacher satisfaction and levels of support for the…

  13. Android worksheet application based on discovery learning on students' achievement for vocational high school: Mechanical behavior of materials topics

    Science.gov (United States)

    Nanto, Dwi; Aini, Anisa Nurul; Mulhayatiah, Diah

    2017-05-01

    This research reports a study of student worksheet based on discovery learning on Mechanical Behavior of Materials topics under Android application (Android worksheet application) for vocational high school. The samples are Architecture class X students of SMKN 4 (a public vocational high school) in Tangerang Selatan City, province of Banten, Indonesia. We made 3 groups based on Intellectual Quotient (IQ). They are average IQ group, middle IQ group and high IQ group. The method of research is used as a quasi-experimental design with nonequivalent control group design. The technique of sampling is purposive sampling. Instruments used in this research are test instruments and non-test instruments. The test instruments are IQ test and test of student's achievement. For the test of student's achievement (pretest and posttest) we provide 25 multiple choice problems. The non-test instruments are questionnaire responses by the students and the teacher. Without IQ categorized, the result showed that there is an effect of Android worksheet application on student's achievement based on cognitive aspects of Revised Bloom's Taxonomy. However, from the IQ groups point of view, only the middle IQ group and the high IQ group showed a significant effect from the Android worksheet application on student's achievement meanwhile for the average IQ group there was no effect.

  14. Exploring Differences between Self-Regulated Learning Strategies of High and Low Achievers in Open Distance Learning

    Science.gov (United States)

    Geduld, Bernadette

    2016-01-01

    Open distance students differ in their preparedness for higher education studies. Students who are less self-regulated risk failure and drop out in the challenging milieu of open distance learning. In this study, the differences between the application of self-regulated learning strategies by low and high achievers were explored. A multi-method…

  15. Histories of terrestrial planets

    International Nuclear Information System (INIS)

    Benes, K.

    1981-01-01

    The uneven historical development of terrestrial planets - Mercury, Venus, Earth, Moon and Mars - is probably due to the differences in their size, weight and rotational dynamics in association with the internal planet structure, their distance from the Sun, etc. A systematic study of extraterrestrial planets showed that the time span of internal activity was not the same for all bodies. It is assumed that the initial history of all terrestrial planets was marked with catastrophic events connected with the overall dynamic development of the solar system. In view of the fact that the cores of small terrestrial bodies cooled quicker, their geological development almost stagnated after two or three thousand million years. This is what probably happened to the Mercury and the Moon as well as the Mars. Therefore, traces of previous catastrophic events were preserved on the surface of the planets. On the other hand, the Earth is the most metamorphosed terrestrial planet and compared to the other planets appears to be atypical. Its biosphere is significantly developed as well as the other shell components, its hydrosphere and atmosphere, and its crust is considerably differentiated. (J.P.)

  16. Terrestrial planet formation.

    Science.gov (United States)

    Righter, K; O'Brien, D P

    2011-11-29

    Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids.

  17. Radionuclides in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Bocock, K.L.

    1981-01-01

    This report summarizes information on the distribution and movement of radionuclides in semi-natural terrestrial ecosystems in north-west England with particular emphasis on inputs to, and outputs from ecosystems; on plant and soil aspects; and on radionuclides in fallout and in discharges by the nuclear industry. (author)

  18. Research and achievements on carbon fiber reinforced thermoplastic composites for high pressure storage

    International Nuclear Information System (INIS)

    Nony, Fabien; Thomas, Cedric; Villalonga, Stephane; Magnier, Christophe

    2012-01-01

    Hydrogen storage is a key enabling technology for the extensive use of hydrogen as an energy carrier. However, none of the current technologies satisfies all of the hydrogen storage attributes sought by manufacturers, legislators and end-users. At present, compressed gaseous hydrogen storage (CGH2) is recognized as the most mature technology. This paper reviews recent developments and achievements regarding materials and technologies investigated by CEA to promote the development of a of type IV 70 MPa hydrogen vessel. Particularly, results concerning innovative thermoplastic matrix composite vessel will be presented and discussed. On going developments on dedicated manufacturing process and material characterization will be shared in a first part of the presentation and a second part will be devoted to durability assessment and damage tolerance of such composite structures with respect to their potential applications. (authors)

  19. A comprehensive approach to decipher biological computation to achieve next generation high-performance exascale computing.

    Energy Technology Data Exchange (ETDEWEB)

    James, Conrad D.; Schiess, Adrian B.; Howell, Jamie; Baca, Michael J.; Partridge, L. Donald; Finnegan, Patrick Sean; Wolfley, Steven L.; Dagel, Daryl James; Spahn, Olga Blum; Harper, Jason C.; Pohl, Kenneth Roy; Mickel, Patrick R.; Lohn, Andrew; Marinella, Matthew

    2013-10-01

    The human brain (volume=1200cm3) consumes 20W and is capable of performing > 10^16 operations/s. Current supercomputer technology has reached 1015 operations/s, yet it requires 1500m^3 and 3MW, giving the brain a 10^12 advantage in operations/s/W/cm^3. Thus, to reach exascale computation, two achievements are required: 1) improved understanding of computation in biological tissue, and 2) a paradigm shift towards neuromorphic computing where hardware circuits mimic properties of neural tissue. To address 1), we will interrogate corticostriatal networks in mouse brain tissue slices, specifically with regard to their frequency filtering capabilities as a function of input stimulus. To address 2), we will instantiate biological computing characteristics such as multi-bit storage into hardware devices with future computational and memory applications. Resistive memory devices will be modeled, designed, and fabricated in the MESA facility in consultation with our internal and external collaborators.

  20. High-Performance Ultraviolet-to-Infrared Broadband Perovskite Photodetectors Achieved via Inter-/Intraband Transitions

    KAUST Repository

    Alwadai, Norah Mohammed Mosfer; Haque, Mohammed; Mitra, Somak; Flemban, Tahani H.; Pak, Yusin; Wu, Tao; Roqan, Iman S.

    2017-01-01

    range, from ultraviolet to infrared light region (λ = 250–1357 nm). Such structure leads to a high photoresponsivity of 28 and 0.22 A/W, for white light and IR illumination, respectively, with high detectivity values of 1.1 × 1012 and 9.3 × 109 Jones

  1. The Effects of Online Interactive Games on High School Students' Achievement and Motivation in History Learning

    Science.gov (United States)

    Lin, Kuan-Cheng; Wei, Yu Che; Hung, Jason C.

    2012-01-01

    Many studies demonstrate that Digital Game Based Learning (DGBL) can foster learning effect. The purpose of this study is to survey whether the online game in junior high school students can encourage learning effect in Taiwan's History. So, the research applied Interactive Game-based Learning System (IGLS) to junior high history teaching as an…

  2. Teachers' Awareness of Cultural Diversity and Academic Achievement in Ninth Grade Academies and Senior High Schools

    Science.gov (United States)

    Whipps-Johnson, Jamellah Renee

    2016-01-01

    High school graduation rates are higher than they have ever been in 40 years, but disparities continue to exist for students of color and students from poverty when compared to their counterparts. High school reform efforts like creating small learning communities are promising, but small schools alone do not improve student outcomes.…

  3. The Effects of Two Scheduling Formats on Student Achievement in a Suburban High School Setting

    Science.gov (United States)

    Jackson, Kenyada Morton

    2013-01-01

    Limited studies have been conducted on the relationship between scheduling formats and academic performance of high school students. At the target high school, students underperform on standardized tests in English language arts (ELA) and math. The purpose of this causal comparative quantitative study was to compare the means of ELA and math test…

  4. Cardiothoracic and Vascular Surgeons Achieve High Rates of K-Award Conversion Into R01 Funding.

    Science.gov (United States)

    Narahari, Adishesh K; Mehaffey, J Hunter; Hawkins, Robert B; Baderdinni, Pranav K; Chandrabhatla, Anirudha S; Tribble, Curtis G; Kron, Irving L; Roeser, Mark E; Walters, Dustin M; Ailawadi, Gorav

    2018-03-14

    Obtaining National Institutes of Health (NIH) R01 funding remains extremely difficult. The utility of career development grants (K awards) for achieving the goal of R01 funding remains debated, particularly for surgeon-scientists. We examined the success rate for cardiothoracic and vascular (CTV) surgeons compared to other specialties in converting K-level grants into R01 equivalents. All K (K08 and K23) grants awarded to surgeons by the NIH between 1992-2017 were identified through NIH RePORTER, an online database combining funding, publications, and patents. Only grants awarded to CTV surgeons were included. Grants active within the past year were excluded. Mann-Whitney U-tests and Chi-squared tests were used to compare groups. A total of 62 K grants awarded to CTV surgeons were identified during this period. Sixteen grants were still active within the last year and excluded from analysis. Twenty-two (48%) of the remaining K awardees successfully transitioned to an R01 or equivalent grant. Awardees with successful conversion published 9 publications per K grant compared to 4 publications for those who did not convert successfully (p=0.01). The median time for successful conversion to an R grant was 5.0 years after the K award start date. Importantly, the 10-year conversion rate to R01 was equal for CTV surgeons compared to other clinician-investigators (52.6% vs 42.5%). CTV surgeons have an equal 10-year conversion rate to first R01 award compared to other clinicians. These data suggest that NIH achieves a good return on investment when funding CTV surgeon-scientists with K-level funding. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  5. High resolution measurement of earthquake impacts on rock slope stability and damage using pre- and post-earthquake terrestrial laser scans

    Science.gov (United States)

    Hutchinson, Lauren; Stead, Doug; Rosser, Nick

    2017-04-01

    Understanding the behaviour of rock slopes in response to earthquake shaking is instrumental in response and relief efforts following large earthquakes as well as to ongoing risk management in earthquake affected areas. Assessment of the effects of seismic shaking on rock slope kinematics requires detailed surveys of the pre- and post-earthquake condition of the slope; however, at present, there is a lack of high resolution monitoring data from pre- and post-earthquake to facilitate characterization of seismically induced slope damage and validate models used to back-analyze rock slope behaviour during and following earthquake shaking. Therefore, there is a need for additional research where pre- and post- earthquake monitoring data is available. This paper presents the results of a direct comparison between terrestrial laser scans (TLS) collected in 2014, the year prior to the 2015 earthquake sequence, with that collected 18 months after the earthquakes and two monsoon cycles. The two datasets were collected using Riegl VZ-1000 and VZ-4000 full waveform laser scanners with high resolution (c. 0.1 m point spacing as a minimum). The scans cover the full landslide affected slope from the toe to the crest. The slope is located in Sindhupalchok District, Central Nepal which experienced some of the highest co-seismic and post-seismic landslide intensities across Nepal due to the proximity to the epicenters (<20 km) of both of the main aftershocks on April 26, 2015 (M 6.7) and May 12, 2015 (M7.3). During the 2015 earthquakes and subsequent 2015 and 2016 monsoons, the slope experienced rockfall and debris flows which are evident in satellite imagery and field photographs. Fracturing of the rock mass associated with the seismic shaking is also evident at scales not accessible through satellite and field observations. The results of change detection between the TLS datasets with an emphasis on quantification of seismically-induced slope damage is presented. Patterns in the

  6. Inspiring science achievement: a mixed methods examination of the practices and characteristics of successful science programs in diverse high schools

    Science.gov (United States)

    Scogin, Stephen C.; Cavlazoglu, Baki; LeBlanc, Jennifer; Stuessy, Carol L.

    2017-08-01

    While the achievement gap in science exists in the US, research associated with our investigation reveals some high school science programs serving diverse student bodies are successfully closing the gap. Using a mixed methods approach, we identified and investigated ten high schools in a large Southwestern state that fit the definition of "highly successful, highly diverse". By conducting interviews with science liaisons associated with each school and reviewing the literature, we developed a rubric identifying specific characteristics associated with successful science programs. These characteristics and practices included setting high expectations for students, providing extensive teacher support for student learning, and utilizing student-centered pedagogy. We used the rubric to assess the successful high school science programs and compare them to other high school science programs in the state (i.e., less successful and less diverse high school science programs). Highly successful, highly diverse schools were very different in their approach to science education when compared to the other programs. The findings from this study will help schools with diverse students to strengthen hiring practices, enhance teacher support mechanisms, and develop student-focused strategies in the classroom that increase science achievement.

  7. High-Speed Non-Volatile Optical Memory: Achievements and Challenges

    Directory of Open Access Journals (Sweden)

    Vadym Zayets

    2017-01-01

    Full Text Available We have proposed, fabricated, and studied a new design of a high-speed optical non-volatile memory. The recoding mechanism of the proposed memory utilizes a magnetization reversal of a nanomagnet by a spin-polarized photocurrent. It was shown experimentally that the operational speed of this memory may be extremely fast above 1 TBit/s. The challenges to realize both a high-speed recording and a high-speed reading are discussed. The memory is compact, integratable, and compatible with present semiconductor technology. If realized, it will advance data processing and computing technology towards a faster operation speed.

  8. 1km Global Terrestrial Carbon Flux: Estimations and Evaluations

    Science.gov (United States)

    Murakami, K.; Sasai, T.; Kato, S.; Saito, M.; Matsunaga, T.; Hiraki, K.; Maksyutov, S. S.

    2017-12-01

    Estimating global scale of the terrestrial carbon flux change with high accuracy and high resolution is important to understand global environmental changes. Furthermore the estimations of the global spatiotemporal distribution may contribute to the political and social activities such as REDD+. In order to reveal the current state of terrestrial carbon fluxes covering all over the world and a decadal scale. The satellite-based diagnostic biosphere model is suitable for achieving this purpose owing to observing on the present global land surface condition uniformly at some time interval. In this study, we estimated the global terrestrial carbon fluxes with 1km grids by using the terrestrial biosphere model (BEAMS). And we evaluated our new carbon flux estimations on various spatial scales and showed the transition of forest carbon stocks in some regions. Because BEAMS required high resolution meteorological data and satellite data as input data, we made 1km interpolated data using a kriging method. The data used in this study were JRA-55, GPCP, GOSAT L4B atmospheric CO2 data as meteorological data, and MODIS land product as land surface satellite data. Interpolating process was performed on the meteorological data because of insufficient resolution, but not on MODIS data. We evaluated our new carbon flux estimations using the flux tower measurement (FLUXNET2015 Datasets) in a point scale. We used 166 sites data for evaluating our model results. These flux sites are classified following vegetation type (DBF, EBF, ENF, mixed forests, grass lands, croplands, shrub lands, Savannas, wetlands). In global scale, the BEAMS estimations was underestimated compared to the flux measurements in the case of carbon uptake and release. The monthly variations of NEP showed relatively high correlations in DBF and mixed forests, but the correlation coefficients of EBF, ENF, and grass lands were less than 0.5. In the meteorological factors, air temperature and solar radiation showed

  9. Donde Estan los Estudiantes Puertorriquenos/os Exitosos? [Where Are the Academically Successful Puerto Rican Students?]: Success Factors of High-Achieving Puerto Rican High School Students

    Science.gov (United States)

    Antrop-Gonzalez, Rene; Velez, William; Garrett, Tomas

    2005-01-01

    This article describes the 4 success factors that 10 working class Puerto Rican urban high school students attributed to their high academic achievement. These success factors were (a) the acquisition of social capital through religiosity and participation in school and community-based extracurricular activities, (b) having a strong Puerto Rican…

  10. Achieving a 100% Renewable Grid: Operating Electric Power Systems with Extremely High Levels of Variable Renewable Energy

    Energy Technology Data Exchange (ETDEWEB)

    Kroposki, Benjamin; Johnson, Brian; Zhang, Yingchen; Gevorgian, Vahan; Denholm, Paul; Hodge, Bri-Mathias; Hannegan, Bryan

    2017-03-01

    What does it mean to achieve a 100% renewable grid? Several countries already meet or come close to achieving this goal. Iceland, for example, supplies 100% of its electricity needs with either geothermal or hydropower. Other countries that have electric grids with high fractions of renewables based on hydropower include Norway (97%), Costa Rica (93%), Brazil (76%), and Canada (62%). Hydropower plants have been used for decades to create a relatively inexpensive, renewable form of energy, but these systems are limited by natural rainfall and geographic topology. Around the world, most good sites for large hydropower resources have already been developed. So how do other areas achieve 100% renewable grids? Variable renewable energy (VRE), such as wind and solar photovoltaic (PV) systems, will be a major contributor, and with the reduction in costs for these technologies during the last five years, large-scale deployments are happening around the world.

  11. Do Children's Executive Functions Account for Associations Between Early Autonomy-Supportive Parenting and Achievement Through High School?

    Science.gov (United States)

    Bindman, Samantha W; Pomerantz, Eva M; Roisman, Glenn I

    2015-08-01

    This study evaluated whether the positive association between early autonomy-supportive parenting and children's subsequent achievement is mediated by children's executive functions. Using observations of mothers' parenting from the NICHD Study of Early Child Care and Youth Development ( N = 1,306), analyses revealed that mothers' autonomy support over the first 3 years of life predicted enhanced executive functions (i.e., inhibition, delay of gratification, and sustained attention) during the year prior to kindergarten and academic achievement in elementary and high school even when mothers' warmth and cognitive stimulation, as well as other factors (e.g., children's early general cognitive skills and mothers' educational attainment) were covaried. Mediation analyses demonstrated that over and above other attributes (e.g., temperament), children's executive functions partially accounted for the association between early autonomy-supportive parenting and children's subsequent achievement.

  12. Achieving high value care for all and the perverse incentives of 340B price agreements.

    Science.gov (United States)

    Whittington, Melanie D; Campbell, Jonathan D; McQueen, R Brett

    2018-04-01

    Section 340B of the Public Health Service Act requires drug manufacturers to enter into price agreements with the Department of Health and Human Services. These agreements result in variation in the price paid to acquire a drug by sector, which complicates the price used in cost-effectiveness analyses. We describe the transactions and sectors in a 340B agreement using a multiple sclerosis drug. Cost-effectiveness estimates were calculated for the drug using drug prices from the manufacturer and payer perspective. We found the amount paid to the manufacturer (340B price) was a good value ($118,256 per quality-adjusted life-year); however, from the payer drug cost perspective, good value ($196,683 per quality-adjusted life-year) was not achieved. Given that emerging value frameworks incorporate cost-effectiveness, these price variations may have downstream negative consequences, including inaccurate coverage and reimbursement policy recommendations. Upcoming policy changes to the 340B program should incentivize pricing schemes hinged on transparency and value.

  13. Methyl mercury in terrestrial compartments

    International Nuclear Information System (INIS)

    Stoeppler, M.; Burow, M.; Padberg, S.; May, K.

    1993-09-01

    On the basis of the analytical methodology available at present the state of the art for the determination of total mercury and of various organometallic compounds of mercury in air, precipitation, limnic systems, soils, plants and biota is reviewed. This is followed by the presentation and discussion of examples for the data obtained hitherto for trace and ultratrace levels of total mercury and mainly methyl mercury in terrestrial and limnic environments as well as in biota. The data discussed stem predominantly from the past decade in which, due to significant methodological progress, many new aspects were elucidated. They include the most important results in this area achieved by the Research Centre (KFA) Juelich within the project 'Origin and Fate of Methyl Mercury' (contracts EV4V-0138-D and STEP-CT90-0057) supported by the Commission of the European Communities, Brussels. (orig.) [de

  14. High-Performance Ultraviolet-to-Infrared Broadband Perovskite Photodetectors Achieved via Inter-/Intraband Transitions

    KAUST Repository

    Alwadai, Norah Mohammed Mosfer

    2017-10-17

    A high-performance vertically injected broadband UV-to-IR photodetector based on Gd-doped ZnO nanorods (NRs)/CH3NH3PbI3 perovskite heterojunction was fabricated on metal substrates. Our perovskite-based photodetector is sensitive to a broad spectral range, from ultraviolet to infrared light region (λ = 250–1357 nm). Such structure leads to a high photoresponsivity of 28 and 0.22 A/W, for white light and IR illumination, respectively, with high detectivity values of 1.1 × 1012 and 9.3 × 109 Jones. Optical characterizations demonstrate that the IR detection is due to intraband transition in the perovskite material. Metal substrate boosts carrier injection, resulting in higher responsivity compared to the conventional devices grown on glass, whereas the presence of Gd increases the ZnO NRs performance. For the first time, the perovskite-based photodetector is demonstrated to extend its detection capability to IR (>1000 nm) with high room temperature responsivity across the detected spectrum, leading to a high-performance ingenious cost-effective UV-to-IR broadband photodetector design for large-scale applications.

  15. Achieving a long-lived high-beta plasma state by energetic beam injection

    Science.gov (United States)

    Guo, H. Y.; Binderbauer, M. W.; Tajima, T.; Milroy, R. D.; Steinhauer, L. C.; Yang, X.; Garate, E. G.; Gota, H.; Korepanov, S.; Necas, A.; Roche, T.; Smirnov, A.; Trask, E.

    2015-04-01

    Developing a stable plasma state with high-beta (ratio of plasma to magnetic pressures) is of critical importance for an economic magnetic fusion reactor. At the forefront of this endeavour is the field-reversed configuration. Here we demonstrate the kinetic stabilizing effect of fast ions on a disruptive magneto-hydrodynamic instability, known as a tilt mode, which poses a central obstacle to further field-reversed configuration development, by energetic beam injection. This technique, combined with the synergistic effect of active plasma boundary control, enables a fully stable ultra-high-beta (approaching 100%) plasma with a long lifetime.

  16. Best practices in heterotrophic high-cell-density microalgal processes: achievements, potential and possible limitations

    Czech Academy of Sciences Publication Activity Database

    Bumbak, F.; Cook, S.; Zachleder, Vilém; Hauser, S.; Kovar, K.

    2011-01-01

    Roč. 91, č. 1 (2011), 31-46 ISSN 0175-7598 Institutional research plan: CEZ:AV0Z50200510 Keywords : Heterotrophic growth * Microalgae * High-celldensity culture Subject RIV: EE - Microbiology, Virology Impact factor: 3.425, year: 2011

  17. Misery in Dark Shadows behind the High Achievement Scores in South Korean Schooling: An Ethnographic Study

    Science.gov (United States)

    Kwon, Soonjung; Kristjánsson, Kristján; Walker, David I.

    2017-01-01

    This article explores some of the hidden background behind the highly praised school results in South Korea. An ethnographic case study is used to cast light on how schooling is actually experienced by South Korean students. Two main results are reported from these data. First, evidence is presented of damaging "cultural elements" such…

  18. A Study of Organizational Justice, Organizational Citizenship Behavior, and Student Achievement in High Schools

    Science.gov (United States)

    Burns, W. R. Travis; DiPaola, Michael F.

    2013-01-01

    Emerging research suggests that teachers' perceptions of fairness with respect to interactions with school administrators, decision-making processes, and decision outcomes can contribute greatly to understanding effective schools. This study of Virginia public high schools used correlational analysis to measure the strength of the relationships…

  19. Time on Text and Science Achievement for High School Biology Students

    Science.gov (United States)

    Wyss, Vanessa L.; Dolenc, Nathan; Kong, Xiaoqing; Tai, Robert H.

    2013-01-01

    The conflict between the amount of material to be addressed in high school science classes, the need to prepare students for standardized tests, and the amount of time available forces science educators to make difficult pedagogical decisions on a daily basis. Hands-on and inquiry-based learning offer students more authentic learning experiences…

  20. Overcoming Adversity: High-Achieving African American Youth's Perspectives on Educational Resilience

    Science.gov (United States)

    Williams, Joseph M.; Bryan, Julia

    2013-01-01

    This qualitative multicase research study identified the home, school, and community factors and processes that contributed to the academic success of 8 urban, African American high school graduates from low-income, single-parent families. Ten main themes emerged: school-related parenting practices, personal stories of hardship, positive…

  1. Improving Climate and Achievement in a Troubled Urban High School through the Talent Development Model.

    Science.gov (United States)

    McPartland, James; Balfanz, Robert; Jordan, Will; Legters, Nettie

    1998-01-01

    A case study of a large nonselective urban high school in Baltimore (Maryland) describes the design and implementation of a comprehensive package of school reforms, the Talent Development Model with Career Academies. Qualitative and quantitative evidence is provided on significant improvements in school climate, student attendance, promotion…

  2. Strategic Culture Change: The Door to Achieving High Performance and Inclusion.

    Science.gov (United States)

    Miller, Frederick A.

    1998-01-01

    Presents diversity as a resource to create a high performing work culture that enables all employees to do their best work. Distinguishes between diversity and inclusion, describes a model for diagnosing an organization's culture, sets forth steps for implementing a organizational change, and discusses the human resource professional's role.…

  3. Achieving and Sustaining New Knowledge Development in High-Expectation Start-Ups

    Science.gov (United States)

    Matricano, Diego

    2010-01-01

    In markets characterized by strong competition, new knowledge and new knowledge development are generally recognized as the key means for an enterprise to gain competitive advantage. This knowledge-based competitive advantage is critical for all commercial ventures, but is especially so for high-expectation start-ups (technology-based ventures…

  4. How to simultaneously achieve low emissions and high efficiency in a hybrid powertrain

    NARCIS (Netherlands)

    Mourad, S.; Eijnden, E. van den; Foster, D.L.; Helden, M. van; Rondel, M.; Schmal, P.

    2001-01-01

    In order to investigate the possibilities of hybrid driveline architecture and to provide a platform for further technical developments, TNO has designed and prototyped a test platform for a series hybrid powertrain, including a compact, highly advanced generator set. This powertrain is subjected to

  5. The effects of using diagramming as a representational technique on high school students' achievement in solving math word problems

    Science.gov (United States)

    Banerjee, Banmali

    Methods and procedures for successfully solving math word problems have been, and continue to be a mystery to many U.S. high school students. Previous studies suggest that the contextual and mathematical understanding of a word problem, along with the development of schemas and their related external representations, positively contribute to students' accomplishments when solving word problems. Some studies have examined the effects of diagramming on students' abilities to solve word problems that only involved basic arithmetic operations. Other studies have investigated how instructional models that used technology influenced students' problem solving achievements. Still other studies have used schema-based instruction involving students with learning disabilities. No study has evaluated regular high school students' achievements in solving standard math word problems using a diagramming technique without technological aid. This study evaluated students' achievement in solving math word problems using a diagramming technique. Using a quasi-experimental experimental pretest-posttest research design, quantitative data were collected from 172 grade 11 Hispanic English language learners (ELLS) and African American learners whose first language is English (EFLLs) in 18 classes at an inner city high school in Northern New Jersey. There were 88 control and 84 experimental students. The pretest and posttest of each participating student and samples of the experimental students' class assignments provided the qualitative data for the study. The data from this study exhibited that the diagramming method of solving math word problems significantly improved student achievement in the experimental group (pvocabulary and symbols used in word problems and that both ELLs and EFLLs improved their problem solving success through careful attention to the creation and labeling of diagrams to represent the mathematics involved in standard word problems. Although Learnertype (ELL, EFLL

  6. High energy density and efficiency achieved in nanocomposite film capacitors via structure modulation

    Science.gov (United States)

    Zeng, Yi; Shen, Zhong-Hui; Shen, Yang; Lin, Yuanhua; Nan, Ce-Wen

    2018-03-01

    Flexible dielectric polymer films with high energy storage density and high charge-discharge efficiency have been considered as promising materials for electrical power applications. Here, we design hierarchical structured nanocomposite films using nonlinear polymer poly(vinylidene fluoride-HFP) [P(VDF-HFP)] with inorganic h-boron nitride (h-BN) nanosheets by electrospinning and hot-pressing methods. Our results show that the addition of h-BN nanosheets and the design of the hierarchical multilayer structure in the nanocomposites can remarkably enhance the charge-discharge efficiency and energy density. A high charge-discharge efficiency of 78% and an energy density of 21 J/cm3 can be realized in the 12-layered PVDF/h-BN nanocomposite films. Phase-field simulation results reveal that the spatial distribution of the electric field in these hierarchical structured films affects the charge-discharge efficiency and energy density. This work provides a feasible route, i.e., structure modulation, to improve the energy storage performances for nanocomposite films.

  7. High-performance lithium storage of Co3O4 achieved by constructing porous nanotube structure

    International Nuclear Information System (INIS)

    Cui, Zhentao; Wang, Shuguang; Zhang, Yihe; Cao, Minhua

    2015-01-01

    Graphical abstract: The porous Co 3 O 4 nanotubes (P-Co 3 O 4 -NTs) are prepared by coaxial electrospinning method followed by a fine annealing treatment. The resultant P-Co 3 O 4 -NTs exhibit excellent lithium storage performance in terms of specific capacity, rate capability, and cycling stability when used as an anode material for rechargeable lithium ion batteries (LIBs). - Abstract: Co 3 O 4 has been investigated intensively for its high specific capacity which makes it a promising candidate anode for high-performance lithium ion batteries (LIBs). However, rational design of Co 3 O 4 electrode that is beneficial for its electrochemical performance is still a great challenge. Herein, we designed and fabricated porous Co 3 O 4 nanotubes (P-Co 3 O 4 -NTs) by coaxial electrospinning method followed by a fine annealing treatment, which display one dimensional tubular structure with porous wall and hollow interior. The uniqueness of this strategy is that the morphologies of the P-Co 3 O 4 -NTs could be tuned by adjusting the mass ratio of reactants. The resultant P-Co 3 O 4 -NTs exhibit excellent lithium storage performance in terms of specific capacity, rate capability, and cycling stability, when used as an anode material for rechargeable LIBs. This unique structure endows a high reversible specific capacity of 1826.2 mA g −1 at a current density of 0.3 A g −1 after 100 cycles. Even at high current densities of 2 and 5 A g −1 , the P-Co 3 O 4 -NTs electrode still could deliver remarkable discharge capacities of 1506.2 and 1145.1 mAh g −1 , respectively. The excellent electrochemical performance can be attributed to the unique tubular and porous structure of P-Co 3 O 4 -NTs, which not only can accommodate the large volume change but also can provide an excellent ion diffusion and electronic conduction pathway. Therefore, the P-Co 3 O 4 -NTs have the potential for use as a high performance anode material in LIBs.

  8. Intersystem Interference Reduction for Overlaid HAPS-Terrestrial CDMA System

    Science.gov (United States)

    Huang, Jeng-Ji; Wang, Wei-Ting; Li, Mingfu; Shiung, David; Ferng, Huei-Wen

    In this letter, we propose that directional antennas, combined with power management, be incorporated to reduce intersystem interference in a shared band overlaid high altitude platform station (HAPS)-terrestrial code division multiple access (CDMA) system. To eliminate the HAPS to terrestrial interference, the HAPS is accessed only via directional antennas under the proposed scheme. By doing so, the uplink power to the HAPS can accordingly be increased, so that the terrestrial to HAPS interference is also effectively suppressed.

  9. Working group 4: Terrestrial

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    A working group at a Canada/USA symposium on climate change and the Arctic identified major concerns and issues related to terrestrial resources. The group examined the need for, and the means of, involving resource managers and users at local and territorial levels in the process of identifying and examining the impacts and consequences of climatic change. Climatic change will be important to the Arctic because of the magnitude of the change projected for northern latitudes; the apparent sensitivity of its terrestrial ecosystems, natural resources, and human support systems; and the dependence of the social, cultural, and economic welfare of Arctic communities, businesses, and industries on the health and quality of their environment. Impacts of climatic change on the physical, biological, and associated socio-economic environment are outlined. Gaps in knowledge needed to quantify these impacts are listed along with their relationships with resource management. Finally, potential actions for response and adaptation are presented

  10. Phytopharmacology of Tribulus terrestris.

    Science.gov (United States)

    Shahid, M; Riaz, M; Talpur, M M A; Pirzada, T

    2016-01-01

    Tribulus terrestris is an annual herb which belongs to the Zygophyllaceae family. This plant has been used in traditional medicine for the treatment of various diseases for hundreds of decades. The main active phytoconstituents of this plant include flavonoids, alkaloids, saponins, lignin, amides, and glycosides. The plant parts have different pharmacological activities including aphrodisiac, antiinflammatory, antimicrobial and antioxidant potential. T. terrestris is most often used for infertility and loss of libido. It has potential application as immunomodulatory, hepatoprotective, hypolipidemic, anthelmintic and anticarcinogenic activities. The aim of the present article is to create a database for further investigation of the phytopharmacological properties of this plant to promote research. This study will definitely help to confirm its traditional use along with its value-added utility, eventually leading to higher revenues from the plant.

  11. Analysis of achievable capacity in irregularly-placed high performance mesh nodes

    CSIR Research Space (South Africa)

    Olwal, TO

    2012-09-01

    Full Text Available -directional antenna for backhaul mesh connectivity and access. The third radio interface card is attached to a 2.4 GHz omni-directional antenna for mesh client access network. As shown in Figure 2, the HPN block diagram has a weather proof Unshielded Twisted Pair... by an embedded microcontroller technology [11]. To ensure high speed performance, the innovation has the first radio interface card attached to a 5 GHz directional antenna for backhaul mesh routing; the second interface card is connected to a 5 GHz omni...

  12. Terrestrial plant methane production

    DEFF Research Database (Denmark)

    Mikkelsen, Teis Nørgaard; Bruhn, Dan; Møller, Ian M.

    We evaluate all experimental work published on the phenomenon of aerobic methane (CH4) generation in terrestrial plants. We conclude that the phenomenon is true. Four stimulating factors have been observed to induce aerobic plant CH4 production, i.e. cutting injuries, increasing temperature...... the aerobic methane emission in plants. Future work is needed for establishing the relative contribution of several proven potential CH4 precursors in plant material....

  13. Achieving graphical excellence: suggestions and methods for creating high-quality visual displays of experimental data.

    Science.gov (United States)

    Schriger, D L; Cooper, R J

    2001-01-01

    Graphics are an important means of communicating experimental data and results. There is evidence, however, that many of the graphics printed in scientific journals contain errors, redundancies, and lack clarity. Perhaps more important, many graphics fail to portray data at an appropriate level of detail, presenting summary statistics rather than underlying distributions. We seek to aid investigators in the production of high-quality graphics that do their investigations justice by providing the reader with optimum access to the relevant aspects of the data. The depiction of by-subject data, the signification of pairing when present, and the use of symbolic dimensionality (graphing different symbols to identify relevant subgroups) and small multiples (the presentation of an array of similar graphics each depicting one group of subjects) to portray stratification are stressed. Step-by-step instructions for the construction of high-quality graphics are offered. We hope that authors will incorporate these suggestions when developing graphics to accompany their manuscripts and that this process will lead to improvements in the graphical literacy of scientific journals. We also hope that journal editors will keep these principles in mind when refereeing manuscripts submitted for peer review.

  14. Texton-based super-resolution for achieving high spatiotemporal resolution in hybrid camera system

    Science.gov (United States)

    Kamimura, Kenji; Tsumura, Norimichi; Nakaguchi, Toshiya; Miyake, Yoichi

    2010-05-01

    Many super-resolution methods have been proposed to enhance the spatial resolution of images by using iteration and multiple input images. In a previous paper, we proposed the example-based super-resolution method to enhance an image through pixel-based texton substitution to reduce the computational cost. In this method, however, we only considered the enhancement of a texture image. In this study, we modified this texton substitution method for a hybrid camera to reduce the required bandwidth of a high-resolution video camera. We applied our algorithm to pairs of high- and low-spatiotemporal-resolution videos, which were synthesized to simulate a hybrid camera. The result showed that the fine detail of the low-resolution video can be reproduced compared with bicubic interpolation and the required bandwidth could be reduced to about 1/5 in a video camera. It was also shown that the peak signal-to-noise ratios (PSNRs) of the images improved by about 6 dB in a trained frame and by 1.0-1.5 dB in a test frame, as determined by comparison with the processed image using bicubic interpolation, and the average PSNRs were higher than those obtained by the well-known Freeman’s patch-based super-resolution method. Compared with that of the Freeman’s patch-based super-resolution method, the computational time of our method was reduced to almost 1/10.

  15. Rachiplusia nu larva as a biofactory to achieve high level expression of horseradish peroxidase.

    Science.gov (United States)

    Romero, Lucía Virginia; Targovnik, Alexandra Marisa; Wolman, Federico Javier; Cascone, Osvaldo; Miranda, María Victoria

    2011-05-01

    A process based on orally-infected Rachiplusia nu larvae as biological factories for expression and one-step purification of horseradish peroxidase isozyme C (HRP-C) is described. The process allows obtaining high levels of pure HRP-C by membrane chromatography purification. The introduction of the partial polyhedrin homology sequence element in the target gene increased HRP-C expression level by 2.8-fold whereas it increased 1.8-fold when the larvae were reared at 27 °C instead of at 24 °C, summing up a 4.6-fold overall increase in the expression level. Additionally, HRP-C purification by membrane chromatography at a high flow rate greatly increase D the productivity without affecting the resolution. The V(max) and K(m) values of the recombinant HRP-C were similar to those of the HRP from Armoracia rusticana roots. © Springer Science+Business Media B.V. 2011

  16. Construction of 3D Skeleton for Polymer Composites Achieving a High Thermal Conductivity.

    Science.gov (United States)

    Yao, Yimin; Sun, Jiajia; Zeng, Xiaoliang; Sun, Rong; Xu, Jian-Bin; Wong, Ching-Ping

    2018-03-01

    Owing to the growing heat removal issue in modern electronic devices, electrically insulating polymer composites with high thermal conductivity have drawn much attention during the past decade. However, the conventional method to improve through-plane thermal conductivity of these polymer composites usually yields an undesired value (below 3.0 Wm -1 K -1 ). Here, construction of a 3D phonon skeleton is reported composed of stacked boron nitride (BN) platelets reinforced with reduced graphene oxide (rGO) for epoxy composites by the combination of ice-templated and infiltrating methods. At a low filler loading of 13.16 vol%, the resulting 3D BN-rGO/epoxy composites exhibit an ultrahigh through-plane thermal conductivity of 5.05 Wm -1 K -1 as the best thermal-conduction performance reported so far for BN sheet-based composites. Theoretical models qualitatively demonstrate that this enhancement results from the formation of phonon-matching 3D BN-rGO networks, leading to high rates of phonon transport. The strong potential application for thermal management has been demonstrated by the surface temperature variations of the composites with time during heating and cooling. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Structural control of side-chain chromophores to achieve highly efficient electro-optic activity.

    Science.gov (United States)

    Yang, Yuhui; Chen, Zhuo; Liu, Jialei; Xiao, Hongyan; Zhen, Zhen; Liu, Xinhou; Jiang, Guohua

    2017-05-10

    A series of chromophores J1-J4 have been synthesized based on julolidine donors modified with different rigid steric hindrance groups. Compared with the chromophore (J1) without the isolation group, chromophores J2, J3 and J4 show better stability. Structural analysis and photophysical property measurements were carried out to compare the molecular mobility and steric hindrance effect of the different donor-modified chromophores. All of these chromophores with isolation groups showed superb thermal stabilities with high thermal decomposition temperatures above 250 °C. Furthermore, with rigid steric hindrance, chromophores J3 and J4 showed more enhanced thermal stabilities with thermal decomposition temperatures of 269 °C and 275 °C, respectively. Density functional theory was used to calculate the hyperpolarizability (β), and the high molecular hyperpolarizability of these chromophores can be effectively translated into large electro-optic coefficients. The electro-optic coefficients of poled films containing 20 wt% of these new chromophores doped in amorphous polycarbonate were 127, 266 and 209 pm V -1 at 1310 nm for chromophores J1-J3, respectively, while the film containing chromophore J4 showed the largest r 33 value of only 97 pm V -1 at 25 wt%. These results indicated that the introduced isolation group can reduce intermolecular electrostatic interactions, thus enhancing the macroscopic electro-optic activity, while the size of the isolation group should be suitable.

  18. Ultrahigh Charpy impact toughness (~450J) achieved in high strength ferrite/martensite laminated steels

    Science.gov (United States)

    Cao, Wenquan; Zhang, Mingda; Huang, Chongxiang; Xiao, Shuyang; Dong, Han; Weng, Yuqing

    2017-02-01

    Strength and toughness are a couple of paradox as similar as strength-ductility trade-off in homogenous materials, body-centered-cubic steels in particular. Here we report a simple way to get ultrahigh toughness without sacrificing strength. By simple alloying design and hot rolling the 5Mn3Al steels in ferrite/austenite dual phase temperature region, we obtain a series of ferrite/martensite laminated steels that show up-to 400-450J Charpy V-notch impact energy combined with a tensile strength as high as 1.0-1.2 GPa at room temperature, which is nearly 3-5 times higher than that of conventional low alloy steels at similar strength level. This remarkably enhanced toughness is mainly attributed to the delamination between ferrite and martensite lamellae. The current finding gives us a promising way to produce high strength steel with ultrahigh impact toughness by simple alloying design and hot rolling in industry.

  19. Receiver-Assisted Congestion Control to Achieve High Throughput in Lossy Wireless Networks

    Science.gov (United States)

    Shi, Kai; Shu, Yantai; Yang, Oliver; Luo, Jiarong

    2010-04-01

    Many applications would require fast data transfer in high-speed wireless networks nowadays. However, due to its conservative congestion control algorithm, Transmission Control Protocol (TCP) cannot effectively utilize the network capacity in lossy wireless networks. In this paper, we propose a receiver-assisted congestion control mechanism (RACC) in which the sender performs loss-based control, while the receiver is performing delay-based control. The receiver measures the network bandwidth based on the packet interarrival interval and uses it to compute a congestion window size deemed appropriate for the sender. After receiving the advertised value feedback from the receiver, the sender then uses the additive increase and multiplicative decrease (AIMD) mechanism to compute the correct congestion window size to be used. By integrating the loss-based and the delay-based congestion controls, our mechanism can mitigate the effect of wireless losses, alleviate the timeout effect, and therefore make better use of network bandwidth. Simulation and experiment results in various scenarios show that our mechanism can outperform conventional TCP in high-speed and lossy wireless environments.

  20. High-Performance and Omnidirectional Thin-Film Amorphous Silicon Solar Cell Modules Achieved by 3D Geometry Design.

    Science.gov (United States)

    Yu, Dongliang; Yin, Min; Lu, Linfeng; Zhang, Hanzhong; Chen, Xiaoyuan; Zhu, Xufei; Che, Jianfei; Li, Dongdong

    2015-11-01

    High-performance thin-film hydrogenated amorphous silicon solar cells are achieved by combining macroscale 3D tubular substrates and nanoscaled 3D cone-like antireflective films. The tubular geometry delivers a series of advantages for large-scale deployment of photovoltaics, such as omnidirectional performance, easier encapsulation, decreased wind resistance, and easy integration with a second device inside the glass tube. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Riparian vegetation in the alpine connectome: Terrestrial-aquatic and terrestrial-terrestrial interactions.

    Science.gov (United States)

    Zaharescu, Dragos G; Palanca-Soler, Antonio; Hooda, Peter S; Tanase, Catalin; Burghelea, Carmen I; Lester, Richard N

    2017-12-01

    Alpine regions are under increased attention worldwide for their critical role in early biogeochemical cycles, their high sensitivity to environmental change, and as repositories of natural resources of high quality. Their riparian ecosystems, at the interface between aquatic and terrestrial environments, play important geochemical functions in the watershed and are biodiversity hotspots, despite a harsh climate and topographic setting. With climate change rapidly affecting the alpine biome, we still lack a comprehensive understanding of the extent of interactions between riparian surface, lake and catchment environments. A total of 189 glacial - origin lakes were surveyed in the Central Pyrenees to test how key elements of the lake and terrestrial environments interact at different scales to shape riparian plant composition. Secondly, we evaluated how underlying ecotope features drive the formation of natural communities potentially sensitive to environmental change and assessed their habitat distribution. At the macroscale, vegetation composition responded to pan-climatic gradients altitude and latitude, which captured in a narrow geographic area the transition between large European climatic zones. Hydrodynamics was the main catchment-scale factor connecting riparian vegetation with major water fluxes, followed by topography and geomorphology. Lake sediment Mg and Pb, and water Mn and Fe contents reflected local influences from mafic bedrock and soil water saturation. Community analysis identified four keystone ecosystems: (i) damp ecotone, (ii) snow bed-silicate bedrock, (iii) wet heath, and (iv) calcareous substrate. These communities and their connections with ecotope elements could be at risk from a number of environmental change factors including warmer seasons, snow line and lowland species advancement, increased nutrient/metal input and water level fluctuations. The results imply important natural terrestrial-aquatic linkages in the riparian environment

  2. Using Wireless Sensor Networks to Achieve Intelligent Monitoring for High-Temperature Gas-Cooled Reactor

    Directory of Open Access Journals (Sweden)

    Jianghai Li

    2017-01-01

    Full Text Available High-temperature gas-cooled reactors (HTGR can incorporate wireless sensor network (WSN technology to improve safety and economic competitiveness. WSN has great potential in monitoring the equipment and processes within nuclear power plants (NPPs. This technology not only reduces the cost of regular monitoring but also enables intelligent monitoring. In intelligent monitoring, large sets of heterogeneous data collected by the WSN can be used to optimize the operation and maintenance of the HTGR. In this paper, WSN-based intelligent monitoring schemes that are specific for applications of HTGR are proposed. Three major concerns regarding wireless technology in HTGR are addressed: wireless devices interference, cybersecurity of wireless networks, and wireless standards selected for wireless platform. To process nonlinear and non-Gaussian data obtained by WSN for fault diagnosis, novel algorithms combining Kernel Entropy Component Analysis (KECA and support vector machine (SVM are developed.

  3. Longitudinal Outcomes of Start Time Delay on Sleep, Behavior, and Achievement in High School.

    Science.gov (United States)

    Thacher, Pamela V; Onyper, Serge V

    2016-02-01

    To establish whether sleep, health, mood, behavior, and academics improved after a 45-minute delay in high school start time, and whether changes persisted longitudinally. We collected data from school records and student self-report across a number of domains at baseline (May 2012) and at two follow-up time points (November 2012 and May 2013), at a public high school in upstate New York. Students enrolled during academic years (AY) 2011-2012 and 2012-2013 completed the Pittsburgh Sleep Quality Index; the DASS-21; the "Owl-Lark" Scale; the Daytime Sleepiness Index; and a brief self-report of health. Reports from school records regarding attendance, tardiness, disciplinary violations, and academic performance were collected for AY 2010-2011 through 2013-2014. Students delayed but did not extend their sleep period; we found lasting improvements in tardiness and disciplinary violations after the start-time delay, but no changes to other variables. At the first follow-up, students reported 20 minutes longer sleep, driven by later rise times and stable bed times. At the second follow-up, students maintained later rise times but delayed bedtimes, returning total sleep to baseline levels. A delay in rise time, paralleling the delay in the start time that occurred, resulted in less tardiness and decreased disciplinary incidents, but larger improvements to sleep patterns may be necessary to affect health, attendance, sleepiness, and academic performance. Later start times improved tardiness and disciplinary issues at this school district. A delay in start time may be a necessary but not sufficient means to increase sleep time and may depend on preexisting individual differences. A commentary on this article appears in this issue on page 267. © 2016 Associated Professional Sleep Societies, LLC.

  4. Exploiting the behaviour of wild malaria vectors to achieve high infection with fungal biocontrol agents

    Science.gov (United States)

    2012-01-01

    Background Control of mosquitoes that transmit malaria has been the mainstay in the fight against the disease, but alternative methods are required in view of emerging insecticide resistance. Entomopathogenic fungi are candidate alternatives, but to date, few trials have translated the use of these agents to field-based evaluations of their actual impact on mosquito survival and malaria risk. Mineral oil-formulations of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were applied using five different techniques that each exploited the behaviour of malaria mosquitoes when entering, host-seeking or resting in experimental huts in a malaria endemic area of rural Tanzania. Results Survival of mosquitoes was reduced by 39-57% relative to controls after forcing upward house-entry of mosquitoes through fungus treated baffles attached to the eaves or after application of fungus-treated surfaces around an occupied bed net (bed net strip design). Moreover, 68 to 76% of the treatment mosquitoes showed fungal growth and thus had sufficient contact with fungus treated surfaces. A population dynamic model of malaria-mosquito interactions shows that these infection rates reduce malaria transmission by 75-80% due to the effect of fungal infection on adult mortality alone. The model also demonstrated that even if a high proportion of the mosquitoes exhibits outdoor biting behaviour, malaria transmission was still significantly reduced. Conclusions Entomopathogenic fungi strongly affect mosquito survival and have a high predicted impact on malaria transmission. These entomopathogens represent a viable alternative for malaria control, especially if they are used as part of an integrated vector management strategy. PMID:22449130

  5. Dietary characterization of terrestrial mammals.

    Science.gov (United States)

    Pineda-Munoz, Silvia; Alroy, John

    2014-08-22

    Understanding the feeding behaviour of the species that make up any ecosystem is essential for designing further research. Mammals have been studied intensively, but the criteria used for classifying their diets are far from being standardized. We built a database summarizing the dietary preferences of terrestrial mammals using published data regarding their stomach contents. We performed multivariate analyses in order to set up a standardized classification scheme. Ideally, food consumption percentages should be used instead of qualitative classifications. However, when highly detailed information is not available we propose classifying animals based on their main feeding resources. They should be classified as generalists when none of the feeding resources constitute over 50% of the diet. The term 'omnivore' should be avoided because it does not communicate all the complexity inherent to food choice. Moreover, the so-called omnivore diets actually involve several distinctive adaptations. Our dataset shows that terrestrial mammals are generally highly specialized and that some degree of food mixing may even be required for most species.

  6. Striving for Excellence Sometimes Hinders High Achievers: Performance-Approach Goals Deplete Arithmetical Performance in Students with High Working Memory Capacity

    Science.gov (United States)

    Crouzevialle, Marie; Smeding, Annique; Butera, Fabrizio

    2015-01-01

    We tested whether the goal to attain normative superiority over other students, referred to as performance-approach goals, is particularly distractive for high-Working Memory Capacity (WMC) students—that is, those who are used to being high achievers. Indeed, WMC is positively related to high-order cognitive performance and academic success, a record of success that confers benefits on high-WMC as compared to low-WMC students. We tested whether such benefits may turn out to be a burden under performance-approach goal pursuit. Indeed, for high achievers, aiming to rise above others may represent an opportunity to reaffirm their positive status—a stake susceptible to trigger disruptive outcome concerns that interfere with task processing. Results revealed that with performance-approach goals—as compared to goals with no emphasis on social comparison—the higher the students’ WMC, the lower their performance at a complex arithmetic task (Experiment 1). Crucially, this pattern appeared to be driven by uncertainty regarding the chances to outclass others (Experiment 2). Moreover, an accessibility measure suggested the mediational role played by status-related concerns in the observed disruption of performance. We discuss why high-stake situations can paradoxically lead high-achievers to sub-optimally perform when high-order cognitive performance is at play. PMID:26407097

  7. Land Cover Mapping in Northern High Latitude Permafrost Regions with Satellite Data: Achievements and Remaining Challenges

    Directory of Open Access Journals (Sweden)

    Annett Bartsch

    2016-11-01

    Full Text Available Most applications of land cover maps that have been derived from satellite data over the Arctic require higher thematic detail than available in current global maps. A range of application studies has been reviewed, including up-scaling of carbon fluxes and pools, permafrost feature mapping and transition monitoring. Early land cover mapping studies were driven by the demand to characterize wildlife habitats. Later, in the 1990s, up-scaling of in situ measurements became central to the discipline of land cover mapping on local to regional scales at several sites across the Arctic. This includes the Kuparuk basin in Alaska, the Usa basin and the Lena Delta in Russia. All of these multi-purpose land cover maps have been derived from Landsat data. High resolution maps (from optical satellite data serve frequently as input for the characterization of periglacial features and also flux tower footprints in recent studies. The most used map to address circumpolar issues is the CAVM (Circum Arctic Vegetation Map based on AVHRR (1 km and has been manually derived. It provides the required thematic detail for many applications, but is confined to areas north of the treeline, and it is limited in spatial detail. A higher spatial resolution circumpolar land cover map with sufficient thematic content would be beneficial for a range of applications. Such a land cover classification should be compatible with existing global maps and applicable for multiple purposes. The thematic content of existing global maps has been assessed by comparison to the CAVM and regional maps. None of the maps provides the required thematic detail. Spatial resolution has been compared to used classes for local to regional applications. The required thematic detail increases with spatial resolution since coarser datasets are usually applied over larger areas covering more relevant landscape units. This is especially of concern when the entire Arctic is addressed. A spatial

  8. Mathematical and numerical models to achieve high speed with special-purpose parallel processors

    International Nuclear Information System (INIS)

    Cheng, H.S.; Wulff, W.; Mallen, A.N.

    1986-01-01

    Historically, safety analyses and plant dynamic simulations have been and still are being carried out be means of detailed FORTRAN codes on expensive mainframe computers in time-consuming batch processing mode. These codes have grown to be so expensive to execute that their utilization depends increasingly on the availability of very expensive supercomputers. Thus, advanced technology for high-speed, low-cost, and accurate plant dynamic simulations is very much needed. Ideally, a low-cost facility based on a modern minicomputer can be dedicated to the staff of a power plant, which is easy and convenient to use, and which can simulate realistically plant transients at faster than real-time speeds. Such a simulation capability can enhance safety and plant utilization. One such simulation facility that has been developed is the Brookhaven National Laboratory (BNL) Plant Analyzer, currently set up for boiling water reactor plant simulations at up to seven times faster than real-time process speeds. The principal hardware components of the BNL Plant Analyzer are two units of special-purpose parallel processors, the AD10 of Applied Dynamics International and a PDP-11/34 host computer

  9. Ambipolar SnOx thin-film transistors achieved at high sputtering power

    Science.gov (United States)

    Li, Yunpeng; Yang, Jia; Qu, Yunxiu; Zhang, Jiawei; Zhou, Li; Yang, Zaixing; Lin, Zhaojun; Wang, Qingpu; Song, Aimin; Xin, Qian

    2018-04-01

    SnO is the only oxide semiconductor to date that has exhibited ambipolar behavior in thin-film transistors (TFTs). In this work, ambipolar behavior was observed in SnOx TFTs fabricated at a high sputtering power of 200 W and post-annealed at 150-250 °C in ambient air. X-ray-diffraction patterns showed polycrystallisation of SnO and Sn in the annealed SnOx films. Scanning-electron-microscopy images revealed that microgrooves appeared after the films were annealed. Clusters subsequently segregated along the microgrooves, and our experiments suggest that they were most likely Sn clusters. Atomic force microscopy images indicate an abrupt increase in film roughness due to the cluster segregations. An important implication of this work is that excess Sn in the film, which has generally been thought to be detrimental to the film quality, may promote the ambipolar conduction when it is segregated from the film to enhance the stoichiometric balance.

  10. Achieving high performance in numerical computations on RISC workstations and parallel systems

    Energy Technology Data Exchange (ETDEWEB)

    Goedecker, S. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Hoisie, A. [Los Alamos National Lab., NM (United States)

    1997-08-20

    The nominal peak speeds of both serial and parallel computers is raising rapidly. At the same time however it is becoming increasingly difficult to get out a significant fraction of this high peak speed from modern computer architectures. In this tutorial the authors give the scientists and engineers involved in numerically demanding calculations and simulations the necessary basic knowledge to write reasonably efficient programs. The basic principles are rather simple and the possible rewards large. Writing a program by taking into account optimization techniques related to the computer architecture can significantly speedup your program, often by factors of 10--100. As such, optimizing a program can for instance be a much better solution than buying a faster computer. If a few basic optimization principles are applied during program development, the additional time needed for obtaining an efficient program is practically negligible. In-depth optimization is usually only needed for a few subroutines or kernels and the effort involved is therefore also acceptable.

  11. How to Achieve High-Quality Oocytes? The Key Role of Myo-Inositol and Melatonin

    Directory of Open Access Journals (Sweden)

    Salvatore Giovanni Vitale

    2016-01-01

    Full Text Available Assisted reproductive technologies (ART have experienced growing interest from infertile patients seeking to become pregnant. The quality of oocytes plays a pivotal role in determining ART outcomes. Although many authors have studied how supplementation therapy may affect this important parameter for both in vivo and in vitro models, data are not yet robust enough to support firm conclusions. Regarding this last point, in this review our objective has been to evaluate the state of the art regarding supplementation with melatonin and myo-inositol in order to improve oocyte quality during ART. On the one hand, the antioxidant effect of melatonin is well known as being useful during ovulation and oocyte incubation, two occasions with a high level of oxidative stress. On the other hand, myo-inositol is important in cellular structure and in cellular signaling pathways. Our analysis suggests that the use of these two molecules may significantly improve the quality of oocytes and the quality of embryos: melatonin seems to raise the fertilization rate, and myo-inositol improves the pregnancy rate, although all published studies do not fully agree with these conclusions. However, previous studies have demonstrated that cotreatment improves these results compared with melatonin alone or myo-inositol alone. We recommend that further studies be performed in order to confirm these positive outcomes in routine ART treatment.

  12. Achieving precision in high density batch mode micro-electro-discharge machining

    International Nuclear Information System (INIS)

    Richardson, Mark T; Gianchandani, Yogesh B

    2008-01-01

    This paper reports a parametric study of batch mode micro-electro-discharge machining (µEDM) of high density features in stainless steel. Lithographically fabricated copper tools with single cross, parallel line and 8 × 8 circle/square array features of 5–100 µm width and 5–75 µm spacing were used to quantify trends in machining tolerance and the impact of debris accumulation. As the tool feature density is increased, debris accumulation effects begin to dominate, eventually degrading both tool and workpiece. Two independent techniques for mitigating this debris buildup are separately investigated. The first is a passivation coating which suppresses spurious discharges triggered from the sidewalls of the machining tool. By this method, the mean tool wear rate decreases from a typical of about 34% to 1.7% and machining non-uniformity reduces from 4.9 µm to 1.1 µm across the workpiece. The second technique involves a two-step machining process that enhances the hydrodynamic removal of machining debris compared to standard methods. This improves surface and edge finish, machining time and tool wear

  13. A descriptive study of high school Latino and Caucasian students' values about math, perceived math achievement and STEM career choice

    Science.gov (United States)

    Rodriguez Flecha, Samuel

    The purpose of this study was to examine high school students' math values, perceived math achievement, and STEM career choice. Participants (N=515) were rural high school students from the U.S. Northwest. Data was collected by administering the "To Do or Not to Do:" STEM pilot survey. Most participants (n=294) were Latinos, followed by Caucasians (n=142). Fifty-three percent of the students rated their math achievement as C or below. Of high math students, 57% were male. Females were 53% of low math students. Caucasians (61%) rated themselves as high in math in a greater proportion than Latinos (39%). Latinos (58%) rated themselves as low in math in a greater proportion than Caucasians (39%). Math Values play a significant role in students' perceived math achievement. Internal math values (r =.68, R2 =.46, p =.001) influenced perceived math achievement regardless of gender (males: r =.70, R2 =.49, p =.001; females: r =.65, R2 =.43, p =.001), for Latinos (r =.66, R2 =.44, p =.001), and Caucasians (r =.72, R2 =.51, p =.001). External math values (r =.53, R2 =.28, p =.001) influenced perceived math achievement regardless of gender (males: r =.54, R2 =.30, p =.001; females: r =.49, R2 =.24, p =.001), for Latinos (r =.47, R2 =.22, p =.001), and Caucasians (r =.58, R2 =.33, p =.001). Most high-math students indicated an awareness of being good at math at around 11 years old. Low-math students said that they realized that math was difficult for them at approximately 13 years of age. The influence of parents, teachers, and peers may vary at different academic stages. Approximately half of the participants said there was not a person who had significantly impacted their career choice; only a minority said their parents and teachers were influencing them to a STEM career. Parents and teachers are the most influential relationships in students' career choice. More exposure to STEM role models and in a variety of professions is needed. Possible strategies to impact students

  14. Analysis of gas turbine engines using water and oxygen injection to achieve high Mach numbers and high thrust

    Science.gov (United States)

    Henneberry, Hugh M.; Snyder, Christopher A.

    1993-01-01

    An analysis of gas turbine engines using water and oxygen injection to enhance performance by increasing Mach number capability and by increasing thrust is described. The liquids are injected, either separately or together, into the subsonic diffuser ahead of the engine compressor. A turbojet engine and a mixed-flow turbofan engine (MFTF) are examined, and in pursuit of maximum thrust, both engines are fitted with afterburners. The results indicate that water injection alone can extend the performance envelope of both engine types by one and one-half Mach numbers at which point water-air ratios reach 17 or 18 percent and liquid specific impulse is reduced to some 390 to 470 seconds, a level about equal to the impulse of a high energy rocket engine. The envelope can be further extended, but only with increasing sacrifices in liquid specific impulse. Oxygen-airflow ratios as high as 15 percent were investigated for increasing thrust. Using 15 percent oxygen in combination with water injection at high supersonic Mach numbers resulted in thrust augmentation as high as 76 percent without any significant decrease in liquid specific impulse. The stoichiometric afterburner exit temperature increased with increasing oxygen flow, reaching 4822 deg R in the turbojet engine at a Mach number of 3.5. At the transonic Mach number of 0.95 where no water injection is needed, an oxygen-air ratio of 15 percent increased thrust by some 55 percent in both engines, along with a decrease in liquid specific impulse of 62 percent. Afterburner temperature was approximately 4700 deg R at this high thrust condition. Water and/or oxygen injection are simple and straightforward strategies to improve engine performance and they will add little to engine weight. However, if large Mach number and thrust increases are required, liquid flows become significant, so that operation at these conditions will necessarily be of short duration.

  15. Achieving organisational competence for clinical leadership: the role of high performance work systems.

    Science.gov (United States)

    Leggat, Sandra G; Balding, Cathy

    2013-01-01

    While there has been substantial discussion about the potential for clinical leadership in improving quality and safety in healthcare, there has been little robust study. The purpose of this paper is to present the results of a qualitative study with clinicians and clinician managers to gather opinions on the appropriate content of an educational initiative being planned to improve clinical leadership in quality and safety among medical, nursing and allied health professionals working in primary, community and secondary care. In total, 28 clinicians and clinician managers throughout the state of Victoria, Australia, participated in focus groups to provide advice on the development of a clinical leadership program in quality and safety. An inductive, thematic analysis was completed to enable the themes to emerge from the data. Overwhelmingly the participants conceptualised clinical leadership in relation to organisational factors. Only four individual factors, comprising emotional intelligence, resilience, self-awareness and understanding of other clinical disciplines, were identified as being important for clinical leaders. Conversely seven organisational factors, comprising role clarity and accountability, security and sustainability for clinical leaders, selective recruitment into clinical leadership positions, teamwork and decentralised decision making, training, information sharing, and transformational leadership, were seen as essential, but the participants indicated they were rarely addressed. The human resource management literature includes these seven components, with contingent reward, reduced status distinctions and measurement of management practices, as the essential organisational underpinnings of high performance work systems. The results of this study propose that clinical leadership is an organisational property, suggesting that capability frameworks and educational programs for clinical leadership need a broader organisation focus. The paper

  16. Thirty Years of Social Science Research on High-Level Nuclear Waste: Achievements and Future Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, Barry D. (Dept. of Social Sciences, Michigan Technological Univ., Houghton (United States)), e-mail: bdsolomo@mtu.edu; Andren, Mats; Strandberg, Urban (Center for Public Sector Research, Univ. of Goeteborg, Goeteborg (Sweden))

    2010-09-15

    Research on high-level nuclear waste management has focused on technical and scientific issues since the U.S. National Academy of Sciences first studied the problem in the mid 1950s and recommended long-term disposal in deep salt formations. In this review, we trace the development of the problem's definition and its associated research since socioeconomic, political and policy issues were first given consideration and nuclear waste management became recognized as more than a technical issue. Three time periods are identified. First, from the mid 1970s to early 1980s, initial research explored institutional dimensions of nuclear waste, including ethics. The second period began in the early 1980s with a concerted effort to solve the problem and site nuclear waste repositories, and ended in the mid 1990s with minimal progress in the U.S. and general stalemate in Asia and Europe (with the notable exception of Sweden). This phase accelerated research on risk perception and stigma of nuclear waste, and elevated a focus on public trust. Great attention was given to repository siting conflicts, while minimal attention was placed on ethics, equity, political systems, and public participation. The last period, since the mid 1990s, has been characterized by continuing political stalemate and increased attention to public participation, political systems and international solutions. Questions of ethics have been given renewed attention, while research on risk perceptions and siting conflicts continues. We frame these periods in a broader context of the shifting role of applied social scientists. The paper concludes with a general discussion of this research area and prospects for future research

  17. Thirty Years of Social Science Research on High-Level Nuclear Waste: Achievements and Future Challenges

    International Nuclear Information System (INIS)

    Solomon, Barry D.; Andren, Mats; Strandberg, Urban

    2010-09-01

    Research on high-level nuclear waste management has focused on technical and scientific issues since the U.S. National Academy of Sciences first studied the problem in the mid 1950s and recommended long-term disposal in deep salt formations. In this review, we trace the development of the problem's definition and its associated research since socioeconomic, political and policy issues were first given consideration and nuclear waste management became recognized as more than a technical issue. Three time periods are identified. First, from the mid 1970s to early 1980s, initial research explored institutional dimensions of nuclear waste, including ethics. The second period began in the early 1980s with a concerted effort to solve the problem and site nuclear waste repositories, and ended in the mid 1990s with minimal progress in the U.S. and general stalemate in Asia and Europe (with the notable exception of Sweden). This phase accelerated research on risk perception and stigma of nuclear waste, and elevated a focus on public trust. Great attention was given to repository siting conflicts, while minimal attention was placed on ethics, equity, political systems, and public participation. The last period, since the mid 1990s, has been characterized by continuing political stalemate and increased attention to public participation, political systems and international solutions. Questions of ethics have been given renewed attention, while research on risk perceptions and siting conflicts continues. We frame these periods in a broader context of the shifting role of applied social scientists. The paper concludes with a general discussion of this research area and prospects for future research

  18. The effect of online quizzes on student achievement in high school chemistry

    Science.gov (United States)

    Deeter, Christopher L.

    The idea of student engagement has come to the forefront of the United States educational system over the past decade. Student engagement requires learners to be actively involved in all stages of the learning process. This study focuses on the use of online quizzes in the chemistry classroom as a means to help students become more engaged in their learning outside of the classroom. Students were given three different types of online quizzes over the course of a chemistry chapter. Student scores on end of the chapter examinations was used to determine whether there was a significant difference in the amount of learning that occurred when a student took each of the three types of online quizzes. Students in a private parochial high school chemistry class completed online quizzes over the course of a semester. The quizzes were taken after completing assigned readings from the chemistry text. After each reading, a third of the students took online multiple-choice quizzes, a third took a paragraph quiz, and a third took no quiz. Scores received from end of chapter tests were evaluated to determine if the impact each of the quiz types had on the learning. All statistical analysis was done using SPSS using two-way split plot ANOVA with condition (paragraph, multiple-choice, nothing) as the within subject factor and group (A, B, C) as between subject factor. The data indicates that there was no significance within the condition F (1.877, 90.087) =.996, p>.05, or the interaction results. F (3.754, 90.087) =.509, p>.05. The data indicated that the effect of group was not significant either. F (2, 48) =.981, p>.05. Interviews undertaken to explain this outcome discovered that students did not become engaged with the content until the night before each test. When they did so, they used a teacher-provided study guide as their primary learning tool.

  19. Drought-avoiding plants with low water use can achieve high rainfall retention without jeopardising survival on green roofs.

    Science.gov (United States)

    Szota, Christopher; Farrell, Claire; Williams, Nicholas S G; Arndt, Stefan K; Fletcher, Tim D

    2017-12-15

    Green roofs are increasingly being used among the suite of tools designed to reduce the volume of surface water runoff generated by cities. Plants provide the primary mechanism for restoring the rainfall retention capacity of green roofs, but selecting plants with high water use is likely to increase drought stress. Using empirically-derived plant physiological parameters, we used a water balance model to assess the trade-off between rainfall retention and plant drought stress under a 30-year climate scenario. We compared high and low water users with either drought avoidance or drought tolerance strategies. Green roofs with low water-using, drought-avoiding species achieved high rainfall retention (66-81%) without experiencing significant drought stress. Roofs planted with other strategies showed high retention (72-90%), but they also experienced >50days of drought stress per year. However, not all species with the same strategy behaved similarly, therefore selecting plants based on water use and drought strategy alone does not guarantee survival in shallow substrates where drought stress can develop quickly. Despite this, it is more likely that green roofs will achieve high rainfall retention with minimal supplementary irrigation if planted with low water users with drought avoidance strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Volumetric modulated arc therapy for lung stereotactic radiation therapy can achieve high local control rates.

    Science.gov (United States)

    Yamashita, Hideomi; Haga, Akihiro; Takahashi, Wataru; Takenaka, Ryousuke; Imae, Toshikazu; Takenaka, Shigeharu; Nakagawa, Keiichi

    2014-11-11

    The aim of this study was to report the outcome of primary or metastatic lung cancer patients undergoing volumetric modulated arc therapy for stereotactic body radiation therapy (VMAT-SBRT). From October 2010 to December 2013, consecutive 67 lung cancer patients received single-arc VMAT-SBRT using an Elekta-synergy system. All patients were treated with an abdominal compressor. The gross tumor volumes were contoured on 10 respiratory phases computed tomography (CT) datasets from 4-dimensional (4D) CT and merged into internal target volumes (ITVs). The planning target volume (PTV) margin was isotropically taken as 5 mm. Treatment was performed with a D95 prescription of 50 Gy (43 cases) or 55 Gy (12 cases) in 4 fractions for peripheral tumor or 56 Gy in 7 fractions (12 cases) for central tumor. Among the 67 patients, the median age was 73 years (range, 59-95 years). Of the patients, male was 72% and female 28%. The median Karnofsky performance status was 90-100% in 39 cases (58%) and 80-90% in 20 cases (30%). The median follow-up was 267 days (range, 40-1162 days). Tissue diagnosis was performed in 41 patients (61%). There were T1 primary lung tumor in 42 patients (T1a in 28 patients, T1b in 14 patients), T2 in 6 patients, three T3 in 3 patients, and metastatic lung tumor in 16 patients. The median mean lung dose was 6.87 Gy (range, 2.5-15 Gy). Six patients (9%) developed radiation pneumonitis required by steroid administration. Actuarial local control rate were 100% and 100% at 1 year, 92% and 75% at 2 years, and 92% and 75% at 3 years in primary and metastatic lung cancer, respectively (p =0.59). Overall survival rate was 83% and 84% at 1 year, 76% and 53% at 2 years, and 46% and 20% at 3 years in primary and metastatic lung cancer, respectively (p =0.12). Use of VMAT-based delivery of SBRT in primary in metastatic lung tumors demonstrates high local control rates and low risk of normal tissue complications.

  1. Volumetric modulated arc therapy for lung stereotactic radiation therapy can achieve high local control rates

    International Nuclear Information System (INIS)

    Yamashita, Hideomi; Haga, Akihiro; Takahashi, Wataru; Takenaka, Ryousuke; Imae, Toshikazu; Takenaka, Shigeharu; Nakagawa, Keiichi

    2014-01-01

    The aim of this study was to report the outcome of primary or metastatic lung cancer patients undergoing volumetric modulated arc therapy for stereotactic body radiation therapy (VMAT-SBRT). From October 2010 to December 2013, consecutive 67 lung cancer patients received single-arc VMAT-SBRT using an Elekta-synergy system. All patients were treated with an abdominal compressor. The gross tumor volumes were contoured on 10 respiratory phases computed tomography (CT) datasets from 4-dimensional (4D) CT and merged into internal target volumes (ITVs). The planning target volume (PTV) margin was isotropically taken as 5 mm. Treatment was performed with a D95 prescription of 50 Gy (43 cases) or 55 Gy (12 cases) in 4 fractions for peripheral tumor or 56 Gy in 7 fractions (12 cases) for central tumor. Among the 67 patients, the median age was 73 years (range, 59–95 years). Of the patients, male was 72% and female 28%. The median Karnofsky performance status was 90-100% in 39 cases (58%) and 80-90% in 20 cases (30%). The median follow-up was 267 days (range, 40–1162 days). Tissue diagnosis was performed in 41 patients (61%). There were T1 primary lung tumor in 42 patients (T1a in 28 patients, T1b in 14 patients), T2 in 6 patients, three T3 in 3 patients, and metastatic lung tumor in 16 patients. The median mean lung dose was 6.87 Gy (range, 2.5-15 Gy). Six patients (9%) developed radiation pneumonitis required by steroid administration. Actuarial local control rate were 100% and 100% at 1 year, 92% and 75% at 2 years, and 92% and 75% at 3 years in primary and metastatic lung cancer, respectively (p = 0.59). Overall survival rate was 83% and 84% at 1 year, 76% and 53% at 2 years, and 46% and 20% at 3 years in primary and metastatic lung cancer, respectively (p = 0.12). Use of VMAT-based delivery of SBRT in primary in metastatic lung tumors demonstrates high local control rates and low risk of normal tissue complications

  2. Relationships Among Student-body Composition, School Process, and Mathematics Achievement in Argentina’s High Schools

    Directory of Open Access Journals (Sweden)

    Rubén Alberto Cervini Iturre

    2003-05-01

    Full Text Available This is a study of the relationships between the student-body composition of the school, some characteristics of the scholastic process—culture and school climate—according to learners’ perceptions, and the mathematics achievement of students in the last year of high school in Argentina. The data used came from the 1998 National Census of High School Completion, carried out by the nation’s Ministry of Culture and Education. The file contains data for 135,000 students of 2,708 schools in 25 states. Multilevel linear modeling with three levels (student, school and state was applied. A strong relationship was detected between mathematics achievement and the variables student-body composition and school process. When both variables acted together, the effect of other variables experienced a pronounced descent. Although reduced, the variables of the process influenced the student’s achievement. There was identified for future works a reference model which would evaluate other institutional learning factors.

  3. Terrestrial Zone Exoplanets and Life

    Science.gov (United States)

    Matthews, Brenda

    2018-01-01

    One of the most exciting results from ALMA has been the detection of significant substructure within protoplanetary disks that can be linked to planet formation processes. For the first time, we are able to observe the process of assembly of material into larger bodies within such disks. It is not possible, however, for ALMA to probe the growth of planets in protoplanetary disks at small radii, i.e., in the terrestrial zone, where we expect rocky terrestrial planets to form. In this regime, the optical depths prohibit observation at the high frequencies observed by ALMA. To probe the effects of planet building processes and detect telltale gaps and signatures of planetary mass bodies at such small separations from the parent star, we require a facility of superior resolution and sensitivity at lower frequencies. The ngVLA is just such a facility. We will present the fundamental science that will be enabled by the ngVLA in protoplanetary disk structure and the formation of planets. In addition, we will discuss the potential for an ngVLA facility to detect the molecules that are the building blocks of life, reaching limits well beyond those reachable with the current generation of telescopes, and also to determine whether such planets will be habitable based on studies of the impact of stars on their nearest planetary neighbours.

  4. Global screening for Critical Habitat in the terrestrial realm.

    Science.gov (United States)

    Brauneder, Kerstin M; Montes, Chloe; Blyth, Simon; Bennun, Leon; Butchart, Stuart H M; Hoffmann, Michael; Burgess, Neil D; Cuttelod, Annabelle; Jones, Matt I; Kapos, Val; Pilgrim, John; Tolley, Melissa J; Underwood, Emma C; Weatherdon, Lauren V; Brooks, Sharon E

    2018-01-01

    Critical Habitat has become an increasingly important concept used by the finance sector and businesses to identify areas of high biodiversity value. The International Finance Corporation (IFC) defines Critical Habitat in their highly influential Performance Standard 6 (PS6), requiring projects in Critical Habitat to achieve a net gain of biodiversity. Here we present a global screening layer of Critical Habitat in the terrestrial realm, derived from global spatial datasets covering the distributions of 12 biodiversity features aligned with guidance provided by the IFC. Each biodiversity feature is categorised as 'likely' or 'potential' Critical Habitat based on: 1. Alignment between the biodiversity feature and the IFC Critical Habitat definition; and 2. Suitability of the spatial resolution for indicating a feature's presence on the ground. Following the initial screening process, Critical Habitat must then be assessed in-situ by a qualified assessor. This analysis indicates that a total of 10% and 5% of the global terrestrial environment can be considered as likely and potential Critical Habitat, respectively, while the remaining 85% did not overlap with any of the biodiversity features assessed and was classified as 'unknown'. Likely Critical Habitat was determined principally by the occurrence of Key Biodiversity Areas and Protected Areas. Potential Critical Habitat was predominantly characterised by data representing highly threatened and unique ecosystems such as ever-wet tropical forests and tropical dry forests. The areas we identified as likely or potential Critical Habitat are based on the best available global-scale data for the terrestrial realm that is aligned with IFC's Critical Habitat definition. Our results can help businesses screen potential development sites at the early project stage based on a range of biodiversity features. However, the study also demonstrates several important data gaps and highlights the need to incorporate new and

  5. High Brain Ammonia Tolerance and Down-Regulation of Na+:K+:2Cl- Cotransporter 1b mRNA and Protein Expression in the Brain of the Swamp Eel, Monopterus albus, Exposed to Environmental Ammonia or Terrestrial Conditions

    Science.gov (United States)

    Ip, Yuen K.; Hou, Zhisheng; Chen, Xiu L.; Ong, Jasmine L. Y.; Chng, You R.; Ching, Biyun; Hiong, Kum C.; Chew, Shit F.

    2013-01-01

    Na+:K+:2Cl- cotransporter 1 (NKCC1) has been implicated in mediating ischemia-, trauma- or ammonia-induced astrocyte swelling/brain edema in mammals. This study aimed to determine the effects of ammonia or terrestrial exposure on ammonia concentrations in the plasma and brain, and the mRNA expression and protein abundance of nkcc/Nkcc in the brain, of the swamp eel Monopterus albus . Ammonia exposure led to a greater increase in the ammonia concentration in the brain of M. albus than terrestrial exposure. The brain ammonia concentration of M. albus reached 4.5 µmol g-1 and 2.7 µmol g-1 after 6 days of exposure to 50 mmol l-1 NH4Cl and terrestrial conditions, respectively. The full cDNA coding sequence of nkcc1b from M. albus brain comprised 3276 bp and coded for 1092 amino acids with an estimated molecular mass of 119.6 kDa. A molecular characterization indicated that it could be activated through phosphorylation and/or glycosylation by osmotic and/or oxidative stresses. Ammonia exposure for 1 day or 6 days led to significant decreases in the nkcc1b mRNA expression and Nkcc1b protein abundance in the brain of M. albus. In comparison, a significant decrease in nkcc1b mRNA expression was observed in the brain of M. albus only after 6 days of terrestrial exposure, but both 1 day and 6 days of terrestrial exposure resulted in significant decreases in the protein abundance of Nkcc1b. These results are novel because it has been established in mammals that ammonia up-regulates NKCC1 expression in astrocytes and NKCC1 plays an important role in ammonia-induced astrocyte swelling and brain edema. By contrast, our results indicate for the first time that M. albus is able to down-regulate the mRNA and protein expression of nkcc1b/Nkcc1b in the brain when confronted with ammonia toxicity, which could be one of the contributing factors to its extraordinarily high brain ammonia tolerance. PMID:24069137

  6. Terrestrial gamma-ray flashes

    Science.gov (United States)

    Marisaldi, Martino; Fuschino, Fabio; Labanti, Claudio; Tavani, Marco; Argan, Andrea; Del Monte, Ettore; Longo, Francesco; Barbiellini, Guido; Giuliani, Andrea; Trois, Alessio; Bulgarelli, Andrea; Gianotti, Fulvio; Trifoglio, Massimo

    2013-08-01

    Lightning and thunderstorm systems in general have been recently recognized as powerful particle accelerators, capable of producing electrons, positrons, gamma-rays and neutrons with energies as high as several tens of MeV. In fact, these natural systems turn out to be the highest energy and most efficient natural particle accelerators on Earth. Terrestrial Gamma-ray Flashes (TGFs) are millisecond long, very intense bursts of gamma-rays and are one of the most intriguing manifestation of these natural accelerators. Only three currently operative missions are capable of detecting TGFs from space: the RHESSI, Fermi and AGILE satellites. In this paper we review the characteristics of TGFs, including energy spectrum, timing structure, beam geometry and correlation with lightning, and the basic principles of the associated production models. Then we focus on the recent AGILE discoveries concerning the high energy extension of the TGF spectrum up to 100 MeV, which is difficult to reconcile with current theoretical models.

  7. Terrestrial gamma-ray flashes

    International Nuclear Information System (INIS)

    Marisaldi, Martino; Fuschino, Fabio; Labanti, Claudio; Tavani, Marco; Argan, Andrea; Del Monte, Ettore; Longo, Francesco; Barbiellini, Guido; Giuliani, Andrea; Trois, Alessio; Bulgarelli, Andrea; Gianotti, Fulvio; Trifoglio, Massimo

    2013-01-01

    Lightning and thunderstorm systems in general have been recently recognized as powerful particle accelerators, capable of producing electrons, positrons, gamma-rays and neutrons with energies as high as several tens of MeV. In fact, these natural systems turn out to be the highest energy and most efficient natural particle accelerators on Earth. Terrestrial Gamma-ray Flashes (TGFs) are millisecond long, very intense bursts of gamma-rays and are one of the most intriguing manifestation of these natural accelerators. Only three currently operative missions are capable of detecting TGFs from space: the RHESSI, Fermi and AGILE satellites. In this paper we review the characteristics of TGFs, including energy spectrum, timing structure, beam geometry and correlation with lightning, and the basic principles of the associated production models. Then we focus on the recent AGILE discoveries concerning the high energy extension of the TGF spectrum up to 100 MeV, which is difficult to reconcile with current theoretical models

  8. A study of mini-channel thermal module design for achieving high stability and high capability in electronic cooling

    International Nuclear Information System (INIS)

    Wang, Hsiang-Li; Wu, Huang-Ching; Kong Wang, S.; Hung, Tzu-Chen; Yang, Ruey-Jen

    2013-01-01

    In this study, pressure drop and heat transfer characteristics of multiple-mini-channel thermal modules were investigated quantitatively. The flow channels, which were mounted on one side of a copper test section, were designed in three types: (1) the first module consists of fourteen straight and parallel channels with a rectangular cross section of 1 mm × 3 mm, (2) the second module consists of fourteen gradually widening channels with a U-shaped cross section starting from an inlet section of 0.5 mm × 3 mm and increasing to an outlet section of 1 mm × 3 mm, and (3) the third module is similar to the second module except for the rectangular cross section. Visual observations and the measured boiling curves show that, in the straight channels, some bubbles cannot be flushed out of the channels fast enough, so they tend to flow back and accumulate at the entrance. This results in a rather dry channel condition for CHF (critical heat flux) to occur for the cases with low flow rates. For the widening channel modules, no occurrence of CHF was observed under an even lower operating pressure in an attempt to induce the incipient of CHF. Under a similar temperature rise at the channel exit, the maximum heat removal rate of the widening channels reaches 27 W/cm 2 which is at least twice as high as that of the straight channels. -- Highlights: ► Three mini-channel modules were designed, and experiments were carried out on pressure drop and heat transfer characteristics. ► Comparisons were made between one regular straight-channel module and two widening-channel modules with rectangular and U-shaped cross sections. ► It was found that the widening channels yield a stable two-phase heat transfer mode with no occurrence of CHF due to a better movement of the bubbles and the absence of backflow which causes accumulation of bubbles commonly occur at the entrance of the straight-shaped parallel channels. ► The maximum heat removal rate of the widening channels reaches

  9. Parent Rated Symptoms of Inattention in Childhood Predict High School Academic Achievement Across Two Culturally and Diagnostically Diverse Samples

    Directory of Open Access Journals (Sweden)

    Astri J. Lundervold

    2017-08-01

    Full Text Available Objective: To investigate parent reports of childhood symptoms of inattention as a predictor of adolescent academic achievement, taking into account the impact of the child’s intellectual functioning, in two diagnostically and culturally diverse samples.Method: Samples: (a an all-female sample in the U.S. predominated by youth with ADHD (Berkeley Girls with ADHD Longitudinal Study [BGALS], N = 202, and (b a mixed-sex sample recruited from a Norwegian population-based sample (the Bergen Child Study [BCS], N = 93. Inattention and intellectual function were assessed via the same measures in the two samples; academic achievement scores during and beyond high school and demographic covariates were country-specific.Results: Childhood inattention predicted subsequent academic achievement in both samples, with a somewhat stronger effect in the BGALS sample, which included a large subgroup of children with ADHD. Intellectual function was another strong predictor, but the effect of early inattention remained statistically significant in both samples when intellectual function was covaried.Conclusion: The effect of early indicators of inattention on future academic success was robust across the two samples. These results support the use of remediation procedures broadly applied. Future longitudinal multicenter studies with pre-planned common inclusion criteria should be performed to increase our understanding of the importance of inattention in primary school children for concurrent and prospective functioning.

  10. Arctic Terrestrial Biodiversity Monitoring Plan

    DEFF Research Database (Denmark)

    Christensen, Tom; Payne, J.; Doyle, M.

    The Conservation of Arctic Flora and Fauna (CAFF), the biodiversity working group of the Arctic Council, established the Circumpolar Biodiversity Monitoring Program (CBMP) to address the need for coordinated and standardized monitoring of Arctic environments. The CBMP includes an international...... on developing and implementing long-term plans for monitoring the integrity of Arctic biomes: terrestrial, marine, freshwater, and coastal (under development) environments. The CBMP Terrestrial Expert Monitoring Group (CBMP-TEMG) has developed the Arctic Terrestrial Biodiversity Monitoring Plan (CBMP......-Terrestrial Plan/the Plan) as the framework for coordinated, long-term Arctic terrestrial biodiversity monitoring. The goal of the CBMP-Terrestrial Plan is to improve the collective ability of Arctic traditional knowledge (TK) holders, northern communities, and scientists to detect, understand and report on long...

  11. Effects of Full-Time and Part-Time High-Ability Programs on Developments in Students' Achievement Emotions

    Science.gov (United States)

    Hornstra, Lisette; van der Veen, Ineke; Peetsma, Thea

    2017-01-01

    This study focused on effects of high-ability programs on students' achievement emotions, i.e. emotions that students experience that are associated with achievement activities. Participants were students in grade 4-6 of primary education: 218 students attended full-time high-ability programs, 245 attended part-time high-ability programs (i.e.…

  12. U.S. Math Performance in Global Perspective: How Well Does Each State Do at Producing High-Achieving Students? PEPG Report No.: 10-19

    Science.gov (United States)

    Hanushek, Eric A.; Peterson, Paul E.; Woessmann, Ludger

    2010-01-01

    To see how well U.S. schools do at producing high-achieving math students, the authors compare the percentage of U.S. public and private school students in the graduating Class of 2009 who were highly accomplished in mathematics in each of the 50 states and in 10 urban districts to percentages of high achievers in 56 other countries. Their…

  13. Comparative Climatology of Terrestrial Planets

    Science.gov (United States)

    Mackwell, Stephen J.; Simon-Miller, Amy A.; Harder, Jerald W.; Bullock, Mark A.

    Public awareness of climate change on Earth is currently very high, promoting significant interest in atmospheric processes. We are fortunate to live in an era where it is possible to study the climates of many planets, including our own, using spacecraft and groundbased observations as well as advanced computational power that allows detailed modeling. Planetary atmospheric dynamics and structure are all governed by the same basic physics. Thus differences in the input variables (such as composition, internal structure, and solar radiation) among the known planets provide a broad suite of natural laboratory settings for gaining new understanding of these physical processes and their outcomes. Diverse planetary settings provide insightful comparisons to atmospheric processes and feedbacks on Earth, allowing a greater understanding of the driving forces and external influences on our own planetary climate. They also inform us in our search for habitable environments on planets orbiting distant stars, a topic that was a focus of Exoplanets, the preceding book in the University of Arizona Press Space Sciences Series. Quite naturally, and perhaps inevitably, our fascination with climate is largely driven toward investigating the interplay between the early development of life and the presence of a suitable planetary climate. Our understanding of how habitable planets come to be begins with the worlds closest to home. Venus, Earth, and Mars differ only modestly in their mass and distance from the Sun, yet their current climates could scarcely be more divergent. Our purpose for this book is to set forth the foundations for this emerging science and to bring to the forefront our current understanding of atmospheric formation and climate evolution. Although there is significant comparison to be made to atmospheric processes on nonterrestrial planets in our solar system — the gas and ice giants — here we focus on the terrestrial planets, leaving even broader comparisons

  14. Achieving a Collapsible, Strong, and Highly Thermally Conductive Film Based on Oriented Functionalized Boron Nitride Nanosheets and Cellulose Nanofiber.

    Science.gov (United States)

    Wu, Kai; Fang, Jinchao; Ma, Jinrui; Huang, Rui; Chai, Songgang; Chen, Feng; Fu, Qiang

    2017-09-06

    Boron nitride nanosheet (BNNS) films receive wide attention in both academia and industry because of their high thermal conductivity (TC) and good electrical insulation capability. However, the brittleness and low strength of the BNNS film largely limit its application. Herein, functionalized BNNSs (f-BNNSs) with a well-maintained in-plane crystalline structure were first prepared utilizing urea in the aqueous solution via ball-milling for the purpose of improving their stability in water and enhancing the interaction with the polymer matrix. Then, a biodegradable and highly thermally conductive film with an orderly oriented structure based on cellulose nanofibers (CNFs) and f-BNNSs was prepared just by simple vacuum-assisted filtration. The modification of the BNNS and the introduction of the CNF result in a better orientation of the f-BNNS, sufficient connection between f-BNNS themselves, and strong interaction between f-BNNS and CNF, which not only make the prepared composite film strong and tough but also possess higher in-plane TC. An increase of 70% in-plane TC, 63.2% tensile strength, and 77.8% elongation could be achieved for CNF/f-BNNS films, compared with that for CNF/BNNS films at the filler content of 70%. Although at such a high f-BNNS content, this composite film can be bended and folded. It is even more interesting to find that the in-plane TC could be greatly enhanced with the decrease of the thickness of the film, and a value of 30.25 W/m K can be achieved at the thickness of ∼30 μm for the film containing 70 wt % f-BNNS. We believe that this highly thermally conductive film with good strength and toughness could have potential applications in next-generation highly powerful and collapsible electronic devices.

  15. Contaminant exposure in terrestrial vertebrates

    International Nuclear Information System (INIS)

    Smith, Philip N.; Cobb, George P.; Godard-Codding, Celine; Hoff, Dale; McMurry, Scott T.; Rainwater, Thomas R.; Reynolds, Kevin D.

    2007-01-01

    Here we review mechanisms and factors influencing contaminant exposure among terrestrial vertebrate wildlife. There exists a complex mixture of biotic and abiotic factors that dictate potential for contaminant exposure among terrestrial and semi-terrestrial vertebrates. Chemical fate and transport in the environment determine contaminant bioaccessibility. Species-specific natural history characteristics and behavioral traits then play significant roles in the likelihood that exposure pathways, from source to receptor, are complete. Detailed knowledge of natural history traits of receptors considered in conjunction with the knowledge of contaminant behavior and distribution on a site are critical when assessing and quantifying exposure. We review limitations in our understanding of elements of exposure and the unique aspects of exposure associated with terrestrial and semi-terrestrial taxa. We provide insight on taxa-specific traits that contribute, or limit exposure to, transport phenomenon that influence exposure throughout terrestrial systems, novel contaminants, bioavailability, exposure data analysis, and uncertainty associated with exposure in wildlife risk assessments. Lastly, we identify areas related to exposure among terrestrial and semi-terrestrial organisms that warrant additional research. - Both biotic and abiotic factors determine chemical exposure for terrestrial vertebrates

  16. Final LDRD report : science-based solutions to achieve high-performance deep-UV laser diodes.

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Andrew M.; Miller, Mary A.; Crawford, Mary Hagerott; Alessi, Leonard J.; Smith, Michael L.; Henry, Tanya A.; Westlake, Karl R.; Cross, Karen Charlene; Allerman, Andrew Alan; Lee, Stephen Roger

    2011-12-01

    We present the results of a three year LDRD project that has focused on overcoming major materials roadblocks to achieving AlGaN-based deep-UV laser diodes. We describe our growth approach to achieving AlGaN templates with greater than ten times reduction of threading dislocations which resulted in greater than seven times enhancement of AlGaN quantum well photoluminescence and 15 times increase in electroluminescence from LED test structures. We describe the application of deep-level optical spectroscopy to AlGaN epilayers to quantify deep level energies and densities and further correlate defect properties with AlGaN luminescence efficiency. We further review our development of p-type short period superlattice structures as an approach to mitigate the high acceptor activation energies in AlGaN alloys. Finally, we describe our laser diode fabrication process, highlighting the development of highly vertical and smooth etched laser facets, as well as characterization of resulting laser heterostructures.

  17. High-intensity focused ultrasound sonothrombolysis: the use of perfluorocarbon droplets to achieve clot lysis at reduced acoustic power.

    Science.gov (United States)

    Pajek, Daniel; Burgess, Alison; Huang, Yuexi; Hynynen, Kullervo

    2014-09-01

    The purpose of this study was to evaluate use of intravascular perfluorocarbon droplets to reduce the sonication power required to achieve clot lysis with high-intensity focused ultrasound. High-intensity focused ultrasound with droplets was initially applied to blood clots in an in vitro flow apparatus, and inertial cavitation thresholds were determined. An embolic model for ischemic stroke was used to illustrate the feasibility of this technique in vivo. Recanalization with intravascular droplets was achieved in vivo at 24 ± 5% of the sonication power without droplets. Recanalization occurred in 71% of rabbits that received 1-ms pulsed sonications during continuous intravascular droplet infusion (p = 0.041 vs controls). Preliminary experiments indicated that damage was confined to the ultrasonic focus, suggesting that tolerable treatments would be possible with a more tightly focused hemispheric array that allows the whole focus to be placed inside of the main arteries in the human brain. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  18. Engineering the Pores of Biomass-Derived Carbon: Insights for Achieving Ultrahigh Stability at High Power in High-Energy Supercapacitors.

    Science.gov (United States)

    Thangavel, Ranjith; Kaliyappan, Karthikeyan; Ramasamy, Hari Vignesh; Sun, Xueliang; Lee, Yun-Sung

    2017-07-10

    Electrochemical supercapacitors with high energy density are promising devices due to their simple construction and long-term cycling performance. The development of a supercapacitor based on electrical double-layer charge storage with high energy density that can preserve its cyclability at higher power presents an ongoing challenge. Herein, we provide insights to achieve a high energy density at high power with an ultrahigh stability in an electrical double-layer capacitor (EDLC) system by using carbon from a biomass precursor (cinnamon sticks) in a sodium ion-based organic electrolyte. Herein, we investigated the dependence of EDLC performance on structural, textural, and functional properties of porous carbon engineered by using various activation agents. The results demonstrate that the performance of EDLCs is not only dependent on their textural properties but also on their structural features and surface functionalities, as is evident from the electrochemical studies. The electrochemical results are highly promising and revealed that the porous carbon with poor textural properties has great potential to deliver high capacitance and outstanding stability over 300 000 cycles compared with porous carbon with good textural properties. A very low capacitance degradation of around 0.066 % per 1000 cycles, along with high energy density (≈71 Wh kg -1 ) and high power density, have been achieved. These results offer a new platform for the application of low-surface-area biomass-derived carbons in the design of highly stable high-energy supercapacitors. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Terrestrial Water Storage

    Science.gov (United States)

    Rodell, M.; Chambers, D. P.; Famiglietti, J. S.

    2015-01-01

    During 2014 dryness continued in the Northern Hemisphere and relative wetness continued in the Southern Hemisphere (Fig. 2.21; Plate 2.1g). These largely canceled out such that the global land surface began and ended the year with a terrestrial water storage (TWS) anomaly slightly below 0 cm (equivalent height of water; Fig. 2.22). TWS is the sum of groundwater, soil moisture, surface water, snow, and ice. Groundwater responds more slowly to meteorological phenomena than the other components because the overlying soil acts as a low pass filter, but often it has a larger range of variability on multiannual timescales (Rodell and Famiglietti 2001; Alley et al. 2002).In situ groundwater data are only archived and made and Tanzania. The rest of the continent experienced mixed to dry conditions. Significant reductions in TWS in Greenland, Antarctica, and southern coastal Alaska reflect ongoing ice sheet and glacier ablation, not groundwater depletion.

  20. Are High Achievers Successful in Collaborative Learning? An Explorative Study of College Students' Learning Approaches in Team Project-Based Learning

    Science.gov (United States)

    Lee, Hye-Jung; Kim, Hyekyung; Byun, Hyunjung

    2017-01-01

    This study analyses how high-achieving students approach team project-based learning (TPBL) and aims to identify the implications and challenges of TPBL practice in higher education. After interviewing 32 high-achieving students and surveying 1022 additional students at a South Korean university, we found that four factors were particularly…

  1. Patients with History of Colonoscopy Are Less Likely to Achieve High Quality Preparation After Implementing Split-Dose Bowel Preparation.

    Science.gov (United States)

    Madhoun, M F; Bitar, H; Parava, P; Bashir, M H; Zia, H

    2017-01-01

    Anecdotally, we observed that patients who had previous colonoscopies were less likely to follow newly implemented split-dose bowel preparation (SDBP) instructions. We investigated whether the indication for colonoscopy is an independent factor for achieving high quality bowel preparation among patients asked to follow SDBP. We performed a retrospective study of data from 1478 patients who received outpatient colonoscopies in 2014 (the year of SDBP implementation) at our Veterans Affairs Medical Center. We collected information related to demographics and factors known to affect bowel preparations. Reasons for colonoscopy were dichotomized into surveillance (previous colonoscopy) vs. non-surveillance (positive occult blood test or screening). Bowel preparation quality was scored using the Boston Bowel Preparation Scale (BBPS), and was categorized as either excellent vs. not excellent (BBPS≥7 vs. BBPSquality was excellent in 60% of colonoscopies and adequate in 84% of colonoscopies. Thirty-six percent (535) were surveillance colonoscopies. In multivariate logistic regression analysis, more patients in the non-surveillance group achieved excellent (OR 0.8 ; 95% CI [0.7-0.8], P <0.0001) and adequate (OR 0.8 ; 95% CI [0.7-0.9], P <0.006) bowel preparation than did patients in the surveillance group. Patients with a prior colonoscopy might not follow the split-dose bowel preparation instructions. Educational interventions emphasizing the benefits of SDBP in this group of patients may help ensure compliance and prevent the habitual use of day-before preparations. © Acta Gastro-Enterologica Belgica.

  2. Optimization of conditions to achieve high content of gamma amino butyric acid in germinated black rice, and changes in bioactivities

    Directory of Open Access Journals (Sweden)

    Chaiyavat CHAIYASUT

    Full Text Available Abstract The present study estimated the optimum germination conditions to achieve high content of Gamma-amino butyric acid (GABA and other phytochemicals in Thai black rice cultivar Kum Payao (BR. The Box–Behnken design of response surface methodology was employed to optimize the germination conditions. The changes in the GABA, phytochemical content, impact of salt, and temperature stress variation on phytochemical content, and stability of GABA were studied. The results showed that 12 h of soaking at pH 7, followed by 36 h of germination was the optimum condition to achieve maximum GABA content (0.2029 mg/g of germinated BR (GBR. The temperature (8 and 30 °C, and salt (50-200 mM NaCl content affected the phytochemicals of GBR, especially GABA, and anthocyanins. Obviously, the antioxidant capability, and enzyme (α-amylase and α-glucosidase inhibiting nature of BR was significantly (P < 0.001 increased after germination. The storage of GBR at 4 °C significantly, preserved the GABA content (∼80% for 45 days. Primarily, the current study revealed the changes in phytochemical content, and bioactivity of Thai black rice cr. Kum Payao during germination. More studies should be carried out on pharmacological benefits of GABA-rich GBR.

  3. Developing mathematics learning set for special-needs junior high school student oriented to learning interest and achievement

    Directory of Open Access Journals (Sweden)

    Ai Sadidah

    2016-11-01

    Full Text Available This study aims to produce a mathematics learning set for special-needs students (mathematical learning disability and mathematically gifted of Junior High School Grade VIII Second Semester oriented to learning interests and achievement which is valid, practical, and effective. This study was a research and development study using the Four-D development model consisting of four stages: (1 define, (2 design, (3 develop, and (4 disseminate. The quality of learning set consisting of the following three criterions: (1 validity, (2 practicality, and (3 effectiveness.  The data analysis technique used in this study is a descriptive quantitative analysis. The research produced learning set consisting of lesson plans and student worksheets. The result of the research shows that: (1 the learning set fulfill the valid criteria base on experts’ appraisal; (2 the learning set fulfill the practical criterion base on teacher’s and students’ questionnaire, and observation of learning implementation; (3 the learning set fulfill the effectiveness criterion base on learning interest and achievement.

  4. Glacial and tectonic influence on terrestrial organic carbon delivery to high latitude deep marine systems: IODP Site U1417, Surveyor Fan, Gulf of Alaska

    Science.gov (United States)

    Childress, L. B.; Ridgway, K. D.

    2014-12-01

    Glacial and tectonic processes on active margins are intrinsically coupled to the transport of sediment and associated organic carbon (OC). Glaciation/deglaciation and the formation of ice sheets can alter the quantity and composition of OC delivered to the marine environment. Over geologic time scales (>1 Ma), exhumation and mass wasting of sedimentary rock from uplifted accretionary wedges inject recycled OC (e.g. kerogen), along with modern OC into the marine environment. The sedimentary record of glacial and tectonic processes along the southern Alaska margin is particularly well preserved at Integrated Ocean Drilling Program (IODP) Site U1417. Lithofacies of Site U1417 can be divided into 3 sedimentary packages that we interpret as linked to the onset of tidewater glaciation along, and tectonic convergence of the Yakutat Terrane with, the continental margin of northwestern Canada and southern Alaska. Based on previous studies linking the development of the Cordilleran Ice Sheet and the movement of the Yakutat Terrane to the development of the Surveyor Fan System, we hypothesize biogeochemical variations in the deposited sediments as a result of changing provenance. Preservation of terrestrial OC that has been documented in sediments of the Alaskan continental shelf margin and sediment routing through the deep-sea Surveyor Channel from the Pleistocene to modern time implies a long-term conduit for this OC to reach the distal portion of the Surveyor Fan system. To correlate marine deposits with terrestrial formations, bulk geochemical and detailed biomarker analyses are used to delineate source material. Preliminary bulk OC content and stable carbon isotope analyses of the Yakataga, Poul Creek, and Kultheith Fms. reveal notable differences. Detailed biomarker analysis by pyrolysis-gas chromatograph-mass spectrometry has revealed further differences between the three primary formations. Using the biogeochemical fingerprints of the Yakataga, Poul Creek, and coal

  5. High-Risk Human Papillomaviral Oncogenes E6 and E7 Target Key Cellular Pathways to Achieve Oncogenesis.

    Science.gov (United States)

    Yeo-Teh, Nicole S L; Ito, Yoshiaki; Jha, Sudhakar

    2018-06-08

    Infection with high-risk human papillomavirus (HPV) has been linked to several human cancers, the most prominent of which is cervical cancer. The integration of the viral genome into the host genome is one of the manners in which the viral oncogenes E6 and E7 achieve persistent expression. The most well-studied cellular targets of the viral oncogenes E6 and E7 are p53 and pRb, respectively. However, recent research has demonstrated the ability of these two viral factors to target many more cellular factors, including proteins which regulate epigenetic marks and splicing changes in the cell. These have the ability to exert a global change, which eventually culminates to uncontrolled proliferation and carcinogenesis.

  6. [Why are some high achievers on the course final exam unsuccessful on the proficiency exam in English?].

    Science.gov (United States)

    Matsunuma, Mitsuyasu

    2009-04-01

    This study examined why some high achievers on the course final exam were unsuccessful on the proficiency exam in English. We hypothesized that the learning motives and learning behaviors (learning strategy, learning time) had different effects on the outcomes of the exams. First, the relation between the variables was investigated using structural equation modeling. Second, the learning behaviors of students who got good marks on both exams were compared with students who did well only on the course final exam. The results were as follows. (a) Learning motives influenced test performance via learning behaviors. (b) Content-attached motives influenced all variables concerning learning behaviors. (c) Content-detached motives influenced all variables concerning learning behaviors that were related only to the course final exam. (d) The students who got good marks on both exams performed the learning behaviors that were useful on the proficiency exam more frequently than the students who did well only on the course final exam.

  7. Premigration School Quality, Time Spent in the United States, and the Math Achievement of Immigrant High School Students.

    Science.gov (United States)

    Bozick, Robert; Malchiodi, Alessandro; Miller, Trey

    2016-10-01

    Using a nationally representative sample of 1,189 immigrant youth in American high schools, we examine whether the quality of education in their country of origin is related to post-migration math achievement in the 9th grade. To measure the quality of their education in the country of origin, we use country-specific average test scores from two international assessments: the Programme for International Student Assessment (PISA) and the Trends in International Mathematics and Science Study (TIMSS). We find that the average PISA or TIMSS scores for immigrant youth's country of origin are positively associated with their performance on the 9th grade post-migration math assessment. We also find that each year spent in the United States is positively associated with performance on the 9th grade post-migration math assessment, but this effect is strongest for immigrants from countries with low PISA/TIMSS scores.

  8. Investigation of Learning Behaviors and Achievement of Vocational High School Students Using an Ubiquitous Physics Tablet PC App

    Science.gov (United States)

    Purba, Siska Wati Dewi; Hwang, Wu-Yuin

    2017-06-01

    In this study, we designed and developed an app called Ubiquitous-Physics (U-Physics) for mobile devices like tablet PC or smart phones to help students learn the principles behind a simple pendulum in Physics. The unique characteristic of U-Physics is the use of sensors on mobile devices to collect acceleration and velocity data during pendulum swings. The data collected are transformed to facilitate students' understanding of the pendulum time period. U-Physics helped students understand the effects of pendulum mass, length, and angle in relation to its time period. In addition, U-Physics was equipped with an annotation function such as textual annotation to help students interpret and understand the concepts and phenomena of the simple pendulum. U-Physics also generated graphs automatically to demonstrate the time period during which the pendulum was swinging. Results showed a significant positive correlation between interpreting graphs and applying formula. This finding indicated that the ability to interpret graphs has an important role in scientific learning. Therefore, we strongly recommend that physics teachers use graphs to enrich students' information content and understanding and negative correlation between pair coherence and interpreting graphs. It may be that most of the participants (vocational high school students) have limited skill or confidence in physics problem solving; so, they often seek help from teachers or their high-achieving peers. In addition, the findings also indicated that U-Physics can enhance students' achievement during a 3-week time period. We hope that this app can be globally used to learn physics in the future.

  9. The early evolution of the atmospheres of terrestrial planets

    CERN Document Server

    Raulin, François; Muller, Christian; Nixon, Conor; Astrophysics and Space Science Proceedings : Volume 35

    2013-01-01

    “The Early Evolution of the Atmospheres of Terrestrial Planets” presents the main processes participating in the atmospheric evolution of terrestrial planets. A group of experts in the different fields provide an update of our current knowledge on this topic. Several papers in this book discuss the key role of nitrogen in the atmospheric evolution of terrestrial planets. The earliest setting and evolution of planetary atmospheres of terrestrial planets is directly associated with accretion, chemical differentiation, outgassing, stochastic impacts, and extremely high energy fluxes from their host stars. This book provides an overview of the present knowledge of the initial atmospheric composition of the terrestrial planets. Additionally it includes some papers about the current exoplanet discoveries and provides additional clues to our understanding of Earth’s transition from a hot accretionary phase into a habitable world. All papers included were reviewed by experts in their respective fields. We are ...

  10. Black Phosphorus Based Field Effect Transistors with Simultaneously Achieved Near Ideal Subthreshold Swing and High Hole Mobility at Room Temperature.

    Science.gov (United States)

    Liu, Xinke; Ang, Kah-Wee; Yu, Wenjie; He, Jiazhu; Feng, Xuewei; Liu, Qiang; Jiang, He; Dan Tang; Wen, Jiao; Lu, Youming; Liu, Wenjun; Cao, Peijiang; Han, Shun; Wu, Jing; Liu, Wenjun; Wang, Xi; Zhu, Deliang; He, Zhubing

    2016-04-22

    Black phosphorus (BP) has emerged as a promising two-dimensional (2D) material for next generation transistor applications due to its superior carrier transport properties. Among other issues, achieving reduced subthreshold swing and enhanced hole mobility simultaneously remains a challenge which requires careful optimization of the BP/gate oxide interface. Here, we report the realization of high performance BP transistors integrated with HfO2 high-k gate dielectric using a low temperature CMOS process. The fabricated devices were shown to demonstrate a near ideal subthreshold swing (SS) of ~69 mV/dec and a room temperature hole mobility of exceeding >400 cm(2)/Vs. These figure-of-merits are benchmarked to be the best-of-its-kind, which outperform previously reported BP transistors realized on traditional SiO2 gate dielectric. X-ray photoelectron spectroscopy (XPS) analysis further reveals the evidence of a more chemically stable BP when formed on HfO2 high-k as opposed to SiO2, which gives rise to a better interface quality that accounts for the SS and hole mobility improvement. These results unveil the potential of black phosphorus as an emerging channel material for future nanoelectronic device applications.

  11. Giant energy density and high efficiency achieved in bismuth ferrite-based film capacitors via domain engineering.

    Science.gov (United States)

    Pan, Hao; Ma, Jing; Ma, Ji; Zhang, Qinghua; Liu, Xiaozhi; Guan, Bo; Gu, Lin; Zhang, Xin; Zhang, Yu-Jun; Li, Liangliang; Shen, Yang; Lin, Yuan-Hua; Nan, Ce-Wen

    2018-05-08

    Developing high-performance film dielectrics for capacitive energy storage has been a great challenge for modern electrical devices. Despite good results obtained in lead titanate-based dielectrics, lead-free alternatives are strongly desirable due to environmental concerns. Here we demonstrate that giant energy densities of ~70 J cm -3 , together with high efficiency as well as excellent cycling and thermal stability, can be achieved in lead-free bismuth ferrite-strontium titanate solid-solution films through domain engineering. It is revealed that the incorporation of strontium titanate transforms the ferroelectric micro-domains of bismuth ferrite into highly-dynamic polar nano-regions, resulting in a ferroelectric to relaxor-ferroelectric transition with concurrently improved energy density and efficiency. Additionally, the introduction of strontium titanate greatly improves the electrical insulation and breakdown strength of the films by suppressing the formation of oxygen vacancies. This work opens up a feasible and propagable route, i.e., domain engineering, to systematically develop new lead-free dielectrics for energy storage.

  12. Highly Luminescent Phase-Stable CsPbI3 Perovskite Quantum Dots Achieving Near 100% Absolute Photoluminescence Quantum Yield.

    Science.gov (United States)

    Liu, Feng; Zhang, Yaohong; Ding, Chao; Kobayashi, Syuusuke; Izuishi, Takuya; Nakazawa, Naoki; Toyoda, Taro; Ohta, Tsuyoshi; Hayase, Shuzi; Minemoto, Takashi; Yoshino, Kenji; Dai, Songyuan; Shen, Qing

    2017-10-24

    Perovskite quantum dots (QDs) as a new type of colloidal nanocrystals have gained significant attention for both fundamental research and commercial applications owing to their appealing optoelectronic properties and excellent chemical processability. For their wide range of potential applications, synthesizing colloidal QDs with high crystal quality is of crucial importance. However, like most common QD systems such as CdSe and PbS, those reported perovskite QDs still suffer from a certain density of trapping defects, giving rise to detrimental nonradiative recombination centers and thus quenching luminescence. In this paper, we show that a high room-temperature photoluminescence quantum yield of up to 100% can be obtained in CsPbI 3 perovskite QDs, signifying the achievement of almost complete elimination of the trapping defects. This is realized with our improved synthetic protocol that involves introducing organolead compound trioctylphosphine-PbI 2 (TOP-PbI 2 ) as the reactive precursor, which also leads to a significantly improved stability for the resulting CsPbI 3 QD solutions. Ultrafast kinetic analysis with time-resolved transient absorption spectroscopy evidence the negligible electron or hole-trapping pathways in our QDs, which explains such a high quantum efficiency. We expect the successful synthesis of the "ideal" perovskite QDs will exert profound influence on their applications to both QD-based light-harvesting and -emitting devices.

  13. A novel proxy for terrestrial organic matter in sediments based on branched and isoprenoid tetraether lipids

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Hopmans, E.C.; Weijers, J.W.H.; Schefuß, E.; Herfort, L.; Schouten, S.

    2004-01-01

    We propose a novel tracer for terrestrial organic carbon in sediments based on the analysis of tetraether lipids using high-performance liquid chromatography/mass spectrometry (HPLC/MS). Analysis of terrestrial soil and peats shows that branched tetraether lipids are predominant in terrestrial

  14. Strategies for Constraining the Atmospheres of Temperate Terrestrial Planets with JWST

    Science.gov (United States)

    Batalha, Natasha E.; Lewis, Nikole K.; Line, Michael R.; Valenti, Jeff; Stevenson, Kevin

    2018-04-01

    The Transiting Exoplanet Survey Satellite (TESS) is expected to discover dozens of temperate terrestrial planets orbiting M-dwarfs with atmospheres that could be followed up with the James Webb Space Telescope (JWST). Currently, the TRAPPIST-1 system serves as a benchmark for determining the feasibility and resources required to yield atmospheric constraints. We assess these questions and leverage an information content analysis to determine observing strategies for yielding high-precision spectroscopy in transmission and emission. Our goal is to guide observing strategies of temperate terrestrial planets in preparation for the early JWST cycles. First, we explore JWST’s current capabilities and expected spectral precision for targets near the saturation limits of specific modes. In doing so, we highlight the enhanced capabilities of high-efficiency readout patterns that are being considered for implementation in Cycle 2. We propose a partial saturation strategy to increase the achievable precision of JWST's NIRSpec Prism. We show that JWST has the potential to detect the dominant absorbing gas in the atmospheres of temperate terrestrial planets by the 10th transit using transmission spectroscopy techniques in the near-infrared (NIR). We also show that stacking ⪆10 transmission spectroscopy observations is unlikely to yield significant improvements in determining atmospheric composition. For emission spectroscopy, we show that the MIRI Low Resolution Spectroscopy (LRS) is unlikely to provide robust constraints on the atmospheric composition of temperate terrestrial planets. Higher-precision emission spectroscopy at wavelengths longward of those accessible to MIRI LRS, as proposed in the Origins Space Telescope concept, could help improve the constraints on molecular abundances of temperate terrestrial planets orbiting M-dwarfs.

  15. Novel DDR Processing of Corn Stover Achieves High Monomeric Sugar Concentrations from Enzymatic Hydrolysis (230 g/L) and High Ethanol Concentration (10% v/v) During Fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaowen; Jennings, Ed; Shekiro, Joe; Kuhn, Erik M.; O' Brien, Marykate; Wang, Wei; Schell, Daniel J.; Himmel, Mike; Elander, Richard T.; Tucker, Melvin P.

    2015-04-03

    Distilling and purifying ethanol, butanol, and other products from second and later generation lignocellulosic biorefineries adds significant capital and operating cost for biofuels production. The energy costs associated with distillation affects plant gate and life cycle analysis costs. Lower titers in fermentation due to lower sugar concentrations from pretreatment increase both energy and production costs. In addition, higher titers decrease the volumes required for enzymatic hydrolysis and fermentation vessels. Therefore, increasing biofuels titers has been a research focus in renewable biofuels production for several decades. In this work, we achieved over 200 g/L of monomeric sugars after high solids enzymatic hydrolysis using the novel deacetylation and disc refining (DDR) process on corn stover. The high sugar concentrations and low chemical inhibitor concentrations from the DDR process allowed ethanol titers as high as 82 g/L in 22 hours, which translates into approximately 10 vol% ethanol. To our knowledge, this is the first time that 10 vol% ethanol in fermentation derived from corn stover without any sugar concentration or purification steps has been reported. Techno-economic analysis shows the higher titer ethanol achieved from the DDR process could significantly reduce the minimum ethanol selling price from cellulosic biomass.

  16. Intellectual and personality factors in the achievement of high exam effectiveness in first-year Russian university students

    Directory of Open Access Journals (Sweden)

    Gorchakova, Olesya Yu.

    2016-09-01

    Full Text Available The goals set forth in regulatory documents for the development of Russian education presuppose quantitative evaluation of factors and conditions that ensure students’ achievement of high competence, personality development, and self-realization. Evaluation of intellectual and personality characteristics of first-year university students and study of the relationship among these characteristics thus become important tasks. The research objective was to evaluate relationships among social and abstractlogical types of intelligence, personality characteristics, and exam effectiveness (performance. The study sample was made up of 900 first-year university students (55.2% female and 44.8% male from Tomsk State University who filled in paper-and-pencil forms in Russian: The Evaluation of Choice in Conflict Situations Questionnaire, Raven’s Progressive Matrices, the Self-Organization of Activity, the Reflexivity Type Assessment Test, the Self-Determination Scale, the Satisfaction with Life Scale, and the World Assumptions Scale. Scores on the Unified National Examination in Mathematics (UNE in Mathematics and the first exam results at the university were used to measure academic performance. The data were statistically processed using descriptive analysis, correlation analysis, and factor analysis. The preference for compromising and collaborating strategies indicates a high level of social intelligence and contributes to socio-psychological adaptation of young people to conditions of university education that are new to them, which require greater independence and activity. Social intelligence and abstract-logical intelligence are relatively independent intelligence types. Social intelligence and personality characteristics are not determinants of scores on the UNE in Mathematics. Probably the process of educating students in mathematics in the graduating classes of Russian secondary schools is replaced by training to solve problems on the UNE, so

  17. Ecological transfer mechanisms - Terrestrial

    International Nuclear Information System (INIS)

    Martin, W.E.; Raines, Gilbert E.; Bloom, S.G.; Levin, A.A.

    1969-01-01

    Radionuclides produced by nuclear excavation detonations and released to the environment may enter a variety of biogeochemical cycles and follow essentially the same transfer pathways as their stable-element counterparts. Estimation of potential internal radiation doses to individuals and/or populations living in or near fallout-contaminated areas requires analysis of the food-chain and other ecological pathways by which radionuclides released to the environment may be returned to man. A generalized materials transfer diagram, applicable to the forest, agricultural, freshwater and marine ecosystems providing food and water to the indigenous population of Panama and Colombia in regions that could be affected by nuclear excavation of a sea-level canal between the Atlantic and Pacific Oceans, is presented. Transfer mechanisms effecting the movement of stable elements and radionuclides in terrestrial ecosystems are discussed, and methods used to simulate these processes by means of mathematical models are described to show how intake values are calculated for different radionuclides in the major ecological pathways leading to man. These data provide a basis for estimating potential internal radiation doses for comparison with the radiation protection criteria established by recognized authorities; and this, in turn, provides a basis for recommending measures to insure the radiological safety of the nuclear operation plan. (author)

  18. Solar-terrestrial physics

    International Nuclear Information System (INIS)

    Patel, V.L.

    1977-01-01

    The Glossary is designed to be a technical dictionary that will provide solar workers of various specialties, students, other astronomers and theoreticians with concise information on the nature and the properties of phenomena of solar and solar-terrestrial physics. Each term, or group of related terms, is given a concise phenomenological and quantitative description, including the relationship to other phenomena and an interpretation in terms of physical processes. The references are intended to lead the non-specialist reader into the literature. This section deals with: geomagnetic field; coordinate systems; geomagnetic indices; Dst index; auroral electrojet index AE; daily, 27-day and semi-annual variations of geomagnetic field; micropulsation; geomagnetic storms; storm sudden commencement (SSC) or sudden commencement (SC); initial phase; ring current; sudden impulses; ionosphere; D region; polar cap absorption; sudden ionospheric disturbance; E region; sporadic E; equatorial electrojet; solar flare effect; F 1 and F 2 regions; spread F; travelling ionospheric disturbances; magnetosphere; magnetospheric coordinate systems; plasmasphere; magnetosheath; magnetospheric tail; substorm; radiation belts or Van Allen belts; whistlers; VLF emissions; aurora; auroral forms; auroral oval and auroral zones; auroral intensity; stable auroral red arcs; pulsing aurora; polar glow aurora; and airglow. (B.R.H.)

  19. Ecological transfer mechanisms - Terrestrial

    Energy Technology Data Exchange (ETDEWEB)

    Martin, W E; Raines, Gilbert E; Bloom, S G; Levin, A A [Battelle Memorial Institute, CoIumbus, OH (United States)

    1969-07-01

    Radionuclides produced by nuclear excavation detonations and released to the environment may enter a variety of biogeochemical cycles and follow essentially the same transfer pathways as their stable-element counterparts. Estimation of potential internal radiation doses to individuals and/or populations living in or near fallout-contaminated areas requires analysis of the food-chain and other ecological pathways by which radionuclides released to the environment may be returned to man. A generalized materials transfer diagram, applicable to the forest, agricultural, freshwater and marine ecosystems providing food and water to the indigenous population of Panama and Colombia in regions that could be affected by nuclear excavation of a sea-level canal between the Atlantic and Pacific Oceans, is presented. Transfer mechanisms effecting the movement of stable elements and radionuclides in terrestrial ecosystems are discussed, and methods used to simulate these processes by means of mathematical models are described to show how intake values are calculated for different radionuclides in the major ecological pathways leading to man. These data provide a basis for estimating potential internal radiation doses for comparison with the radiation protection criteria established by recognized authorities; and this, in turn, provides a basis for recommending measures to insure the radiological safety of the nuclear operation plan. (author)

  20. A methodology for achieving high-speed rates for artificial conductance injection in electrically excitable biological cells.

    Science.gov (United States)

    Butera, R J; Wilson, C G; Delnegro, C A; Smith, J C

    2001-12-01

    We present a novel approach to implementing the dynamic-clamp protocol (Sharp et al., 1993), commonly used in neurophysiology and cardiac electrophysiology experiments. Our approach is based on real-time extensions to the Linux operating system. Conventional PC-based approaches have typically utilized single-cycle computational rates of 10 kHz or slower. In thispaper, we demonstrate reliable cycle-to-cycle rates as fast as 50 kHz. Our system, which we call model reference current injection (MRCI); pronounced merci is also capable of episodic logging of internal state variables and interactive manipulation of model parameters. The limiting factor in achieving high speeds was not processor speed or model complexity, but cycle jitter inherent in the CPU/motherboard performance. We demonstrate these high speeds and flexibility with two examples: 1) adding action-potential ionic currents to a mammalian neuron under whole-cell patch-clamp and 2) altering a cell's intrinsic dynamics via MRCI while simultaneously coupling it via artificial synapses to an internal computational model cell. These higher rates greatly extend the applicability of this technique to the study of fast electrophysiological currents such fast a currents and fast excitatory/inhibitory synapses.

  1. Progress achieved in restricting the marketing of high-fat, sugary and salty food and beverage products to children

    Science.gov (United States)

    Vandevijvere, Stefanie; Sacks, Gary; Brinsden, Hannah; Hawkes, Corinna; Barquera, Simón; Lobstein, Tim; Swinburn, Boyd A

    2016-01-01

    Abstract In May 2010, 192 Member States endorsed Resolution WHA63.14 to restrict the marketing of food and non-alcoholic beverage products high in saturated fats, trans fatty acids, free sugars and/or salt to children and adolescents globally. We examined the actions taken between 2010 and early 2016 – by civil society groups, the World Health Organization (WHO) and its regional offices, other United Nations (UN) organizations, philanthropic institutions and transnational industries – to help decrease the prevalence of obesity and diet-related noncommunicable diseases among young people. By providing relevant technical and policy guidance and tools to Member States, WHO and other UN organizations have helped protect young people from the marketing of branded food and beverage products that are high in fat, sugar and/or salt. The progress achieved by the other actors we investigated appears variable and generally less robust. We suggest that the progress being made towards the full implementation of Resolution WHA63.14 would be accelerated by further restrictions on the marketing of unhealthy food and beverage products and by investing in the promotion of nutrient-dense products. This should help young people meet government-recommended dietary targets. Any effective strategies and actions should align with the goal of WHO to reduce premature mortality from noncommunicable diseases by 25% by 2025 and the aim of the UN to ensure healthy lives for all by 2030. PMID:27429493

  2. The Use of Group Activities in Introductory Biology Supports Learning Gains and Uniquely Benefits High-Achieving Students

    Directory of Open Access Journals (Sweden)

    Gili Marbach-Ad

    2016-12-01

    Full Text Available This study describes the implementation and effectiveness of small-group active engagement (GAE exercises in an introductory biology course (BSCI207 taught in a large auditorium setting. BSCI207 (Principles of Biology III—Organismal Biology is the third introductory core course for Biological Sciences majors. In fall 2014, the instructors redesigned one section to include GAE activities to supplement lecture content. One section (n = 198 employed three lectures per week. The other section (n = 136 replaced one lecture per week with a GAE class. We explored the benefits and challenges associated with implementing GAE exercises and their relative effectiveness for unique student groups (e.g., minority students, high- and low-grade point average [GPA] students. Our findings show that undergraduates in the GAE class exhibited greater improvement in learning outcomes than undergraduates in the traditional class. Findings also indicate that high-achieving students experienced the greatest benefit from GAE activities. Some at-risk student groups (e.g., two-year transfer students showed comparably low learning gains in the course, despite the additional support that may have been afforded by active learning. Collectively, these findings provide valuable feedback that may assist other instructors who wish to revise their courses and recommendations for institutions regarding prerequisite coursework approval policies.

  3. Progress achieved in restricting the marketing of high-fat, sugary and salty food and beverage products to children.

    Science.gov (United States)

    Kraak, Vivica I; Vandevijvere, Stefanie; Sacks, Gary; Brinsden, Hannah; Hawkes, Corinna; Barquera, Simón; Lobstein, Tim; Swinburn, Boyd A

    2016-07-01

    In May 2010, 192 Member States endorsed Resolution WHA63.14 to restrict the marketing of food and non-alcoholic beverage products high in saturated fats, trans fatty acids, free sugars and/or salt to children and adolescents globally. We examined the actions taken between 2010 and early 2016 - by civil society groups, the World Health Organization (WHO) and its regional offices, other United Nations (UN) organizations, philanthropic institutions and transnational industries - to help decrease the prevalence of obesity and diet-related noncommunicable diseases among young people. By providing relevant technical and policy guidance and tools to Member States, WHO and other UN organizations have helped protect young people from the marketing of branded food and beverage products that are high in fat, sugar and/or salt. The progress achieved by the other actors we investigated appears variable and generally less robust. We suggest that the progress being made towards the full implementation of Resolution WHA63.14 would be accelerated by further restrictions on the marketing of unhealthy food and beverage products and by investing in the promotion of nutrient-dense products. This should help young people meet government-recommended dietary targets. Any effective strategies and actions should align with the goal of WHO to reduce premature mortality from noncommunicable diseases by 25% by 2025 and the aim of the UN to ensure healthy lives for all by 2030.

  4. Terrestrial forest management plan for Palmyra Atoll

    Science.gov (United States)

    Hathaway, Stacie A.; McEachern, Kathryn; Fisher, Robert N.

    2011-01-01

    This 'Terrestrial Forest Management Plan for Palmyra Atoll' was developed by the U.S. Geological Survey (USGS) for The Nature Conservancy (TNC) Palmyra Program to refine and expand goals and objectives developed through the Conservation Action Plan process. It is one in a series of adaptive management plans designed to achieve TNC's mission toward the protection and enhancement of native wildlife and habitat. The 'Terrestrial Forest Management Plan for Palmyra Atoll' focuses on ecosystem integrity and specifically identifies and addresses issues related to assessing the status and distribution of resources, as well as the pressures acting upon them, most specifically nonnative and potentially invasive species. The plan, which presents strategies for increasing ecosystem integrity, provides a framework to implement and track the progress of conservation and restoration goals related to terrestrial resources on Palmyra Atoll. The report in its present form is intended to be an overview of what is known about historical and current forest resources; it is not an exhaustive review of all available literature relevant to forest management but an attempt to assemble as much information specific to Palmyra Atoll as possible. Palmyra Atoll is one of the Northern Line Islands in the Pacific Ocean southwest of the Hawai`ian Islands. It consists of many heavily vegetated islets arranged in a horseshoe pattern around four lagoons and surrounded by a coral reef. The terrestrial ecosystem consists of three primary native vegetation types: Pisonia grandis forest, coastal strand forest, and grassland. Among these vegetation types, the health and extent of Pisonia grandis forest is of particular concern. Overall, the three vegetation types support 25 native plant species (two of which may be extirpated), 14 species of sea birds, six shore birds, at least one native reptile, at least seven native insects, and six native land crabs. Green and hawksbill turtles forage at Palmyra Atoll

  5. A high-precision 40Ar/39Ar age for the Nördlinger Ries impact crater, Germany, and implications for the accurate dating of terrestrial impact events

    Science.gov (United States)

    Schmieder, Martin; Kennedy, Trudi; Jourdan, Fred; Buchner, Elmar; Reimold, Wolf Uwe

    2018-01-01

    40Ar/39Ar dating of specimens of moldavite, the formation of which is linked to the Ries impact in southern Germany, with a latest-generation ARGUS VI multi-collector mass spectrometer yielded three fully concordant plateau ages with a weighted mean age of 14.808 ± 0.021 Ma (± 0.038 Ma including all external uncertainties; 2σ; MSWD = 0.40, P = 0.67). This new best-estimate age for the Nördlinger Ries is in general agreement with previous 40Ar/39Ar results for moldavites, but constitutes a significantly improved precision with respect to the formation age of the distal Ries-produced tektites. Separates of impact glass from proximal Ries ejecta (suevite glass from three different surface outcrops) and partially melted feldspar particles from impact melt rock of the SUBO 18 Enkingen drill core failed to produce meaningful ages. These glasses show evidence for excess 40Ar introduction, which may have been incurred during interaction with hydrothermal fluids. Only partially reset 40Ar/39Ar ages could be determined for the feldspathic melt separates from the Enkingen core. The new 40Ar/39Ar results for the Ries impact structure constrain the duration of crater cooling, during the prevailing hydrothermal activity, to locally at least ∼60 kyr. With respect to the dating of terrestrial impact events, this paper briefly discusses a number of potential issues and effects that may be the cause for seemingly precise, but on a kyr-scale inaccurate, impact ages.

  6. Aquatic and Terrestrial Environment 2004

    DEFF Research Database (Denmark)

    Andersen, J. M.; Boutrup, S.; Bijl, L. van der

    This report presents the 2004 results of the Danish National Monitoring and Assess-ment Programme for the Aquatic and Terrestrial Environments (NOVANA). 2004 was the first year in which terrestrial nature was included in the monitoring pro-gramme. The report reviews the state of the groundwater......, watercourses, lakes and marine waters and the pressures upon them and reviews the monitoring of terrestrial natural habitats and selected plants and animals. The report is based on the annual reports prepared for each subprogramme by the Topic Centres. The latter reports are mainly based on data collected...

  7. Highlights on R and D work related to the achievement of high burnup with MOX fuel in commercial reactors

    International Nuclear Information System (INIS)

    Lippens, M.; Maldague, Th.; Basselier, J.; Boulanger, D.; Mertens, L.

    2000-01-01

    Part of the R and D work made at BELGONUCLEAIRE in the field of high burnup achievement with MOX fuel in commercial LWRs is made through lnternational Programmes. Special attention is given to the evolution with burnup of fuel neutronic characteristics and of in-reactor rod thermal-mechanical behaviour. Pu burning in MOX is characterized essentially by a drop of Pu 239 content. The other Pu isotopes have an almost unchanged concentration, due to internal breeding. The reactivity drop of MOX versus burnup is consequently much less pronounced than in UO 2 fuel. Concentration of minor actinides Am and Cm becomes significant with burnup increase. These nuclides start to play a role on total reactivity and in the helium production. The thermal-mechanical behaviour of MOX fuel rod is very similar to that of UO 2 . Some specificities are noticed. The better PCI resistance recognized to MOX fuel has recently been confirmed. Three PWR MOX segments pm-irradiated up to 58 GWd/tM were ramped at 100 W/cm.min respectively to 430-450-500 W/cm followed by a hold time of 24 hours. No segment failed. MOX and UO 2 fuels have different reactivities and operate thus at different powers. Moreover, radial distribution of power in MOX pellet is less depressed at high burnup than in UO 2 , leading to higher fuel central temperature for a same rating. The thermal conductivity of MOX fuel decreases with Pu content, typically 4% for 10% Pu. The combination of these three elements (power level, power profile, and conductivity) lead to larger FGR at high burnup compared to UO 2 . Helium production remains low compared to fission gas production (ratio < 0.2). As faster diffusing element, the helium fractional release is much higher than that of fission gas, leading to rod pressure increase comparable to the one resulting from fission gas. (author)

  8. Achievement of high availability in long-term operation and upgrading plan of the LHD superconducting system

    International Nuclear Information System (INIS)

    Imagawa, S.; Yanagi, N.; Hamaguchi, S.

    2006-10-01

    The Large Helical Device (LHD) that has been demonstrating high performance of heliotron plasma is the world's largest superconducting system. Availability higher than 98% has been achieved in a long-term continuous operation both in the cryogenic system and in the power supply system. It will be owing not only to the robustness of the systems but also to efforts of maintenance and operation. One big problem is shortage of cryogenic stability of a pair of pool-cooled helical coils. Composite conductors had been developed to attain the sufficient stability at high current density. However, it was revealed that a normal-zone could propagate below the cold-end recovery current by additional heat generation due to the slow current diffusion into a thick pure aluminium stabilizer. Besides, a novel detection system with pick-up coils along the helical coils revealed that normal-zones were initiated near the bottom of the coil where the field is not the highest. Therefore, the cooling condition around the innermost layers, the high field area, will be deteriorated at the bottom of the coil by bubbles gathered by buoyancy. In order to raise the operating currents, methods for improving the cryogenic stability have been examined, and stability tests have been carried out with a model coil and small coil samples. The coil temperature is planned to be lowered from 4.4 K to 3.5 K, and the operating current is expected to be increased from 11.0 kA to 12.0 kA that corresponds to 3.0 T at the major radius of 3.6 m. (author)

  9. The Impact of Socioeconomic Status on Achievement of High School Students Participating in a One-to-One Laptop Computer Program

    Science.gov (United States)

    Weers, Anthony J.

    2012-01-01

    The purpose of this study was to determine the impact of socioeconomic status on the achievement of high school students participating in a one-to-one laptop computer program. Students living in poverty struggle to achieve in schools across the country, educators must address this issue. The independent variable in this study is socioeconomic…

  10. Patterns of Motivational Beliefs in the Science Learning of Total, High-, and Low-Achieving Students: Evidence of Taiwanese TIMSS 2011 Data

    Science.gov (United States)

    Wang, Cheng-Lung; Liou, Pey-Yan

    2018-01-01

    The purpose of this study was to examine the pattern of the relationships among motivational beliefs and science achievement of 8th grade Taiwanese students, given that the students in Taiwan have high science academic achievement but low motivational beliefs in science learning on a series of international large-scale assessments. Three…

  11. The fragmentation of Pangaea and Mesozoic terrestrial vertebrate biodiversity.

    Science.gov (United States)

    Vavrek, Matthew J

    2016-09-01

    During the Mesozoic (242-66 million years ago), terrestrial regions underwent a massive shift in their size, position and connectivity. At the beginning of the era, the land masses were joined into a single supercontinent called Pangaea. However, by the end of the Mesozoic, terrestrial regions had become highly fragmented, both owing to the drifting apart of the continental plates and the extremely high sea levels that flooded and divided many regions. How terrestrial biodiversity was affected by this fragmentation and large-scale flooding of the Earth's landmasses is uncertain. Based on a model using the species-area relationship (SAR), terrestrial vertebrate biodiversity would be expected to nearly double through the Mesozoic owing to continental fragmentation, despite a decrease of 24% in total terrestrial area. Previous studies of Mesozoic vertebrates have generally found increases in terrestrial diversity towards the end of the era, although these increases are often attributed to intrinsic or climatic factors. Instead, continental fragmentation over this time may largely explain any observed increase in terrestrial biodiversity. This study demonstrates the importance that non-intrinsic effects can have on the taxonomic success of a group, and the importance of geography to understanding past biodiversity. © 2016 The Author(s).

  12. Taiwan's industrial heavy metal pollution threatens terrestrial biota

    International Nuclear Information System (INIS)

    Hsu, M.J.; Selvaraj, K.; Agoramoorthy, G.

    2006-01-01

    The bioconcentration levels of essential (Cu, Fe, Mg, Mn, and Zn) and non-essential (As, Cd, Hg, Pb, and Sn) elements have been investigated in different terrestrial biota such as fungi, plant, earthworm, snail, crab, insect, amphibian, lizard, snake, and bat including the associated soil, to investigate the ecosystem health status in Kenting National Park, Taiwan. High bioconcentrations of Cd, Hg, and Sn in snail, earthworm, crab, lizard, snake, and bat indicated a contaminated terrestrial ecosystem. High concentrations of Cd, Hg, and Sn in plant species, effective bioaccumulation of Cd by earthworm, snail, crab and bat, as well as very high levels of Hg found in invertebrates, amphibians, and reptiles revealed a strong influence from industrial pollution on the biotic community. This study for the first time presents data on the impact of heavy metal pollution on various terrestrial organisms in Taiwan. - Metal effects occur at any terrestrial levels in Taiwan

  13. Optimizing the Parameters in Heat Treatment for Achieving High Hardness and Efficient Bending of Thin BS 2014 Aluminium Alloy Sheets

    Directory of Open Access Journals (Sweden)

    Abirami Priyadarshini B.

    2016-05-01

    Full Text Available The present work targets in setting a standard heat treatment procedure for obtaining high hardness values of the order of 80 HRB in BS 2014 aluminium alloy sheets of 2mm thick commonly used in aerospace industries. A hardness range of 60HRB to 72HRB is possible in low thickness sheets as stated in the standard BS EN 485-2:2013. Experiments were performed to achieve higher hardness values by controlling the heat treatment temperatures thereby understanding the ageing mechanism of the Al-Cu alloy to a wider extent. The validated process sequence in turn resulted in complications where bending of the sheets resulted in cracking. Further investigation was performed and it was found that the BS 2014 alloy has to be bent within two hours of solution annealing in order to have an efficient bending. The results showed that the natural ageing is so rapid in this alloy, which strengthens the material so quickly by the formation of CuAl2 precipitates, thereby, demanding the bending procedure to be performed before the growth of precipitates becomes dominant.

  14. Achieving high performance in intermediate temperature direct carbon fuel cells with renewable carbon as a fuel source

    International Nuclear Information System (INIS)

    Hao, Wenbin; He, Xiaojin; Mi, Yongli

    2014-01-01

    Highlights: • Bamboo fiber and waste paper were pyrolyzed to generate bamboo carbon and waste paper carbon as anode fuels of IT-DCFC. • Superior cell performance was achieved with the waste paper carbon. • The results suggested the high performance was due to the highest thermal reactivity and the catalytic inherent impurities. • Calcite and kaolinite as inherent impurities favored the thermal decomposition and the electrooxidation of carbon. - Abstract: Three kinds of carbon sources obtained from carbon black, bamboo fiber and waste paper were investigated as anode fuels in an intermediate temperature direct carbon fuel cell. The carbon sources were characterized with X-ray photoelectron spectroscopy, thermal gravimetric analysis, etc. The results indicated that the waste paper carbon was more abundant in calcite and kaolinite, and showed higher thermal reactivity in the intermediate temperature range compared with the other two carbon sources. The cell performance was tested at 650 °C in a hybrid single cell, using Sm 0.20 Ce 0.80 O 2−x as the electrolyte. As a result, the cell fed with waste paper carbon showed the highest performance among the three carbon sources, with a peak power density of 225 mW cm −2 . The results indicated that its inherent impurities, such as calcite and kaolinite, might favor the thermal gasification of renewable carbon sources, which resulted in the enhanced performance of the intermediate temperature direct carbon fuel cell

  15. Achievement goals in the classroom and their possible influence on motivational patterns for chemistry learning in two Brazilian high schools

    Directory of Open Access Journals (Sweden)

    Denilson Mendes de Oliveira

    2017-07-01

    Full Text Available Classroom structures constitute motivational aspects to learn, which can be easily manipulated by teachers during mediation of scientific knowledge to ensure students’ engagement. Organization of learning activities, evaluation and autonomy are some examples of such structures. Two types of goals may be developed in classrooms due to different instructional strategies: performance goals and mastery goals. This work’s objectives were to compare instructional strategies of two high school chemistry teachers (Teacher A and Teacher B from two public schools located in Viçosa (Brazil and infer possible motivational patterns found among students. The comparison was based on the achievement goal theory and organized within the three classroom structures. Data were gathered through field notes from participant observation in two Chemistry classes and semi-structured interviews with both of the teachers. It was verified that Teacher A utilized strategies aligned with mastery goals, while Teacher B utilized instructional strategies that were consistent with the two types of goals. It is concluded that this can influence student engagement during Chemistry classes, considering that teachers have an important role in the orchestration of classroom structures, articulating instructional strategies that favor learning and mediation of the scientific knowledge.

  16. A highly efficient surface plasmon polaritons excitation achieved with a metal-coupled metal-insulator-metal waveguide

    Directory of Open Access Journals (Sweden)

    Hongyan Yang

    2014-12-01

    Full Text Available We propose a novel metal-coupled metal-insulator-metal (MC-MIM waveguide which can achieve a highly efficient surface plasmon polaritons (SPPs excitation. The MC-MIM waveguide is formed by inserting a thin metal film in the insulator of an MIM. The introduction of the metal film, functioning as an SPPs coupler, provides a space for the interaction between SPPs and a confined electromagnetic field of the intermediate metal surface, which makes energy change and phase transfer in the metal-dielectric interface, due to the joint action of incomplete electrostatic shielding effect and SPPs coupling. Impacts of the metal film with different materials and various thickness on SPPs excitation are investigated. It is shown that the highest efficient SPPs excitation is obtained when the gold film thickness is 60 nm. The effect of refractive index of upper and lower symmetric dielectric layer on SPPs excitation is also discussed. The result shows that the decay value of refractive index is 0.3. Our results indicate that this proposed MC-MIM waveguide may offer great potential in designing a new SPPs source.

  17. Lab-scale investigation of Middle-Bosnia coals to achieve high-efficient and clean combustion technology

    Directory of Open Access Journals (Sweden)

    Smajevic Izet

    2014-01-01

    Full Text Available This paper describes full lab-scale investigation of Middle-Bosnia coals launched to support selection an appropriate combustion technology and to support optimization of the boiler design. Tested mix of Middle-Bosnia brown coals is projected coal for new co-generation power plant Kakanj Unit 8 (300-450 MWe, EP B&H electricity utility. The basic coal blend consisting of the coals Kakanj: Breza: Zenica at approximate mass ratio of 70:20:10 is low grade brown coal with very high percentage of ash - over 40%. Testing that coal in circulated fluidized bed combustion technique, performed at Ruhr-University Bohum and Doosan Lentjes GmbH, has shown its inconveniency for fluidized bed combustion technology, primarily due to the agglomeration problems. Tests of these coals in PFC (pulverized fuel combustion technology have been performed in referent laboratory at Faculty of Mechanical Engineering of Sarajevo University, on a lab-scale PFC furnace, to provide reliable data for further analysis. The PFC tests results are fitted well with previously obtained results of the burning similar Bosnian coal blends in the PFC dry bottom furnace technique. Combination of the coals shares, the process temperature and the air combustion distribution for the lowest NOx and SO2 emissions was found in this work, provided that combustion efficiency and CO emissions are within very strict criteria, considering specific settlement of lab-scale furnace. Sustainability assessment based on calculation economic and environmental indicators, in combination with Low Cost Planning method, is used for optimization the power plant design. The results of the full lab-scale investigation will help in selection optimal Boiler design, to achieve sustainable energy system with high-efficient and clean combustion technology applied for given coals.

  18. Motives Emanating from Personality Associated with Achievement in a Finnish Senior High School: Physical Activity, Curiosity, and Family Motives

    Science.gov (United States)

    Froiland, John Mark; Mayor, Päivi; Herlevi, Marjaana

    2015-01-01

    Numerous studies indicate that intrinsic motivation predicts academic achievement. However, relatively few have examined various subtypes of intrinsic motivation that predict overall achievement, such as motivation for exercise and physical activity. Based upon the 16 basic desires theory of personality, the current study examined the motives of…

  19. The Influence of Emotions and Learning Preferences on Learning Strategy Use before Transition into High-Achiever Track Secondary School

    Science.gov (United States)

    Obergriesser, Stefanie; Stoeger, Heidrun

    2016-01-01

    Research on the relationships between students' achievement emotions and their (self-regulated) learning behavior is growing. However, little is known about the relationships between students' learning preferences and achievement emotions and the extent to which these influence learning strategies. In this study we, first, looked at the…

  20. Quality Education in Idaho: A Case Study of Academic Achievement in Three High-Poverty Rural Schools

    Science.gov (United States)

    Brown, Christine

    2017-01-01

    The focus of this research is bridging the achievement gap for students living in poverty through quality education. Such a study is important because the percentage of students affected by poverty is increasing and the persistent gap in achievement evidences that the right to quality education for students in poverty is not being met. This is…

  1. The Effect of Teaching Methods and Learning Styles on Students’ English Achievement (An Experimental Study at Junior High School 1 Pasangkayu

    Directory of Open Access Journals (Sweden)

    Syahrul Munir

    2019-10-01

    Full Text Available The objectives of the research are to determine the effects of teaching methods (STAD and jigsaw and learning styles (visual, auditory, and kinesthetic on students’ English achievement. This research is an experimental study conducted at Junior High School Pasangkayu in 2014 with 213 sample which is selected stratified-randomly (n = 68. The results of the research are as follow: (1 English achievement of students taught with STAD is better than those of taught with jigsaw; (2 there is no significant difference in  English achievement among visual, auditory, and kinesthetic students; (3 there is any significant effect of interaction among teaching method and learning styles on students’ learning English achievement. The research also find out that for visual students, studying English achievement of students taught with STAD is better than that of students taught with jigsaw; for auditory students, learning English achievement  of students taught with jigsaw is better than that of students taught with STAD; and for kinesthetic students, English achievement of students taught with STAD is better than that of students taught with jigsaw. To sum up, STAD is more effective than jigsaw in improving students’ English achievement. STAD is suitable to improve English achievement of visual and kinesthetic students, and jigsaw is suitable to improve English achievement of auditory students.

  2. An analysis of predictors of enrollment and successful achievement for girls in high school Advanced Placement physics

    Science.gov (United States)

    Depalma, Darlene M.

    A problem within science education in the United States persists. U.S students rank lower in science than most other students from participating countries on international tests of achievement (National Center for Education Statistics, 2003). In addition, U.S. students overall enrollment rate in high school Advanced Placement (AP) physics is still low compared to other academic domains, especially for females. This problem is the background for the purpose of this study. This investigation examined cognitive and motivational variables thought to play a part in the under-representation of females in AP physics. Cognitive variables consisted of mathematics, reading, and science knowledge, as measured by scores on the 10th and 11th grade Florida Comprehensive Assessment Tests (FCAT). The motivational factors of attitude, stereotypical views toward science, self-efficacy, and epistemological beliefs were measured by a questionnaire developed with questions taken from previously proven reliable and valid instruments. A general survey regarding participation in extracurricular activities was also included. The sample included 12th grade students from two high schools located in Seminole County, Florida. Of the 106 participants, 20 girls and 27 boys were enrolled in AP physics, and 39 girls and 20 boys were enrolled in other elective science courses. Differences between males and females enrolled in AP physics were examined, as well as differences between females enrolled in AP physics and females that chose not to participate in AP physics, in order to determine predictors that apply exclusively to female enrollment in high school AP physics and predictors of an anticipated science related college major. Data were first analyzed by Exploratory Factor Analysis, followed by Analysis of Variance (ANOVA), independent t-tests, univariate analysis, and logistic regression analysis. One overall theme that emerged from this research was findings that refute the ideas that

  3. Working Memory Load and Reminder Effect on Event-Based Prospective Memory of High- and Low-Achieving Students in Math.

    Science.gov (United States)

    Chen, Youzhen; Lian, Rong; Yang, Lixian; Liu, Jianrong; Meng, Yingfang

    The effects of working memory (WM) demand and reminders on an event-based prospective memory (PM) task were compared between students with low and high achievement in math. WM load (1- and 2-back tasks) was manipulated as a within-subject factor and reminder (with or without reminder) as a between-subject factor. Results showed that high-achieving students outperformed low-achieving students on all PM and n-back tasks. Use of a reminder improved PM performance and thus reduced prospective interference; the performance of ongoing tasks also improved for all students. Both PM and n-back performances in low WM load were better than in high WM load. High WM load had more influence on low-achieving students than on high-achieving students. Results suggest that low-achieving students in math were weak at PM and influenced more by high WM load. Thus, it is important to train these students to set up an obvious reminder for their PM and improve their WM.

  4. An Evaluation of Instructional Coaching at Selected High Schools in North Louisiana and Its Effect on Student Achievement, Organizational Climate, and Teacher Efficacy

    Science.gov (United States)

    Hearn, Richard M.

    2010-01-01

    The purpose of this study was to compare high schools in north Louisiana to determine if the presence or absence of instructional coaches influenced student achievement, organizational climate, and/or teacher efficacy in any significant manner. The 11 high schools in north Louisiana utilizing instructional coaches were matched to 11 high schools…

  5. Terrestrial carbohydrates support freshwater zooplankton during phytoplankton deficiency.

    Science.gov (United States)

    Taipale, Sami J; Galloway, Aaron W E; Aalto, Sanni L; Kahilainen, Kimmo K; Strandberg, Ursula; Kankaala, Paula

    2016-08-11

    Freshwater food webs can be partly supported by terrestrial primary production, often deriving from plant litter of surrounding catchment vegetation. Although consisting mainly of poorly bioavailable lignin, with low protein and lipid content, the carbohydrates from fallen tree leaves and shoreline vegetation may be utilized by aquatic consumers. Here we show that during phytoplankton deficiency, zooplankton (Daphnia magna) can benefit from terrestrial particulate organic matter by using terrestrial-origin carbohydrates for energy and sparing essential fatty acids and amino acids for somatic growth and reproduction. Assimilated terrestrial-origin fatty acids from shoreline reed particles exceeded available diet, indicating that Daphnia may convert a part of their dietary carbohydrates to saturated fatty acids. This conversion was not observed with birch leaf diets, which had lower carbohydrate content. Subsequent analysis of 21 boreal and subarctic lakes showed that diet of herbivorous zooplankton is mainly based on high-quality phytoplankton rich in essential polyunsaturated fatty acids. The proportion of low-quality diets (bacteria and terrestrial particulate organic matter) was <28% of the assimilated carbon. Taken collectively, the incorporation of terrestrial carbon into zooplankton was not directly related to the concentration of terrestrial organic matter in experiments or lakes, but rather to the low availability of phytoplankton.

  6. Terrestrial ecosystems in a changing world

    Energy Technology Data Exchange (ETDEWEB)

    Canadell, J.G. [CSIRO Marine and Atmospheric Research, Canberra, ACT (Australia). Global Carbon Project; Pataki, D.E. [California Univ., Irvine, CA (United States). Dept. of Earth System Science]|[California Univ., Irvine, CA (United States). Dept. of Ecology and Evolutionary Biology; Pitelka, L.F. (eds.) [Maryland Univ., Frostburg, MD (United States). Appalachian Lab.

    2007-07-01

    Over 100 authors present 25 contributions on the impacts of global change on terrestrial ecosystems including: * key processes of the earth system such as the CO2 fertilization effect, shifts in disturbances and biome distribution, the saturation of the terrestrial carbon sink, and changes in functional biodiversity, * ecosystem services such the production of wheat, pest control, and carbon storage in croplands, and * sensitive regions in the world threaten by rapid changes in climate and land use such as high latitudes ecosystems, tropical forest in Southeast Asia, and ecosystems dominated by Monsoon climate. The book also explores new research developments on spatial thresholds and nonlinearities, the key role of urban development in global biogeochemical processes, and the integration of natural and social sciences to address complex problems of the human-environment system. (orig.)

  7. Effect factors for terrestrial acidification in Brazil

    DEFF Research Database (Denmark)

    Crespo Mendes, Natalia; Laurent, Alexis; Hauschild, Michael Zwicky

    conditions, which is an essential approach considering countries like Brazil, with high biodiversity. Previous studies have assessed the impacts of terrestrial acidification from the estimations of the potential losses of vascular plants species richness as a result of exposure to acidifying substances...... for 13 biomes, with 2409 species addressed for whole world. In this context this work aims to provide spatially-differentiated effect factors (EF) for terrestrial acidification in Brazil and support the development of spatially-differentiated characterization factors for Brazil. In order to maintain...... in Brazil, represented by 33167 species, indicating that this is a comprehensive study. Maps of soil pH in Brazil were extracted at 1-km resolution and pH values were extracted for the depth range of 0-30cm. For each ecoregion, species richness was plotted against soil pH and the exposure-response curves...

  8. High-Performance All-Polymer Solar Cells Achieved by Fused Perylenediimide-Based Conjugated Polymer Acceptors.

    Science.gov (United States)

    Yin, Yuli; Yang, Jing; Guo, Fengyun; Zhou, Erjun; Zhao, Liancheng; Zhang, Yong

    2018-05-09

    We report three n-type polymeric electron acceptors (PFPDI-TT, PFPDI-T, and PFPDI-Se) based on the fused perylene diimide (FPDI) and thieno[3,2- b]thiophene, thiophene, or selenophene units for all-polymer solar cells (all-PSCs). These FPDI-based polymer acceptors exhibit strong absorption between 350 and 650 nm with wide optical bandgap of 1.86-1.91 eV, showing good absorption compensation with the narrow bandgap polymer donor. The lowest unoccupied molecular orbital (LUMO) energy levels were located at around -4.11 eV, which are comparable with those of the fullerene derivatives and other small molecular electron acceptors. The conventional all-PSCs based on the three polymer acceptors and PTB7-Th as polymer donor gave remarkable power conversion efficiencies (PCEs) of >6%, and the PFPDI-Se-based all-PSC achieved the highest PCE of 6.58% with a short-circuit current density ( J sc ) of 13.96 mA/cm 2 , an open-circuit voltage ( V oc ) of 0.76 V, and a fill factor (FF) of 62.0%. More interestingly, our results indicate that the photovoltaic performances of the FPDI-based polymer acceptors are mainly determined by the FPDI unit with a small effect from the comonomers, which is quite different from the others reported rylenediimide-based polymer acceptors. This intriguing phenomenon is speculated as the huge geometry configuration of the FPDI unit, which minimizes the effect of the comonomer. These results highlight a promising future for the application of the FPDI-based polymer acceptors in the highly efficient all-PSCs.

  9. Broad-Scale Comparison of Photosynthesis in Terrestrial and Aquatic Plant Communities

    DEFF Research Database (Denmark)

    Sand-Jensen, Kaj; Krause-Jensen, D.

    1997-01-01

    Comparisons of photosynthesis in terrestrial and aquatic habitats have been impaired by differences in methods and time-scales of measurements. We compiled information on gross photosynthesis at high irradiance and photosynthetic efficiency at low irradiance from 109 published terrestrial studies...... communities probably due to more efficient light utilization and gas exchange in the terrestrial habitats. By contrast only small differences were found within different aquatic plant communities or within different terrestrial plant communities....... of forests, grasslands and crops and 319 aquatic studies of phytoplankton, macrophyte and attached microalgal communities to test if specific differences existed between the communities. Maximum gross photosynthesis and photosynthetic efficiency were systematically higher in terrestrial than in aquatic...

  10. The effect of the flipped classroom on urban high school students' motivation and academic achievement in a high school science course

    Science.gov (United States)

    Dixon, Keshia L.

    This study investigated the effect of the flipped classroom on urban high school students' motivation and academic achievement in a high school science course. In this quantitative study, the sample population was comprised of North Star High School 12th grade students enrolled in human anatomy and physiology. A quasi-experimental, pretest-posttest non-equivalent group design was conducted. After receipt of Liberty University Institutional Review Board approval and the school district's Department of Research and Evaluation for School Improvement, students completed a pretest comprised of the Science Motivation Questionnaire II (SMQ-II) and the Human Anatomy and Physiology Unit Test. Participants in the experimental group engaged in the treatment, the flipped classroom, using instructional materials on the educational website, Edmodo(TM), and applied content material taught using hands-on activities inclusive of assigned laboratory experiments. Participants in the control group received instruction using traditional face-to-face lecture-homework format while also engaging in assigned laboratory experiments. After the completion of the treatment all participants completed a posttest. Data from both the pretest and posttest was statistically analyzed individually using two separate one-way ANOVA/ANCOVA analyses; and researcher reported the results of the statistical analyses. After completion of the analyses, and interpretation of the results, recommendations for future research were given.

  11. Recent achievements of SIRGAS

    Science.gov (United States)

    Brunini, C.; Sánchez, L.

    2008-05-01

    SIRGAS is the geocentric reference system for the Americas. Its definition corresponds to the IERS International Terrestrial Reference System (ITRS) and it is realized by a regional densification of the IERS International Terrestrial Reference Frame (ITRF). The SIRGAS activities are coordinated by three working groups: SIRGAS-WGI (Reference System) is committed to establish and maintain a continental-wide geocentric reference frame within the ITRF. This objective was initially accomplished through two continental GPS campaigns in 1995 and 2000, including 58 and 184 stations, respectively. Today, it is realized by around 130 continuously operating GNSS sites, which are processed weekly by the IGS Regional Network Associate Analysis Centre for SIRGAS (IGS- RNAAC-SIR). SIRGAS-WGII (Geocentric Datum) is primarily in charged of defining the SIRGAS geodetic datum in the individual countries, which is given by the origin, orientation and scale of the SIRGAS system, and the parameters of the GRS80 ellipsoid. It is concentrating on promoting and supporting the adoption of SIRGAS in the Latin American and Caribbean countries through national densifications of the continental network. SIRGAS- WGIII (Vertical Datum) is dedicated to the definition and realization of a unified vertical reference system within a global frame. Its central purpose is to refer the geopotential numbers (or physical heights) in all countries to one and the same equipotential surface (W0), which must be globally defined. This includes also the transformation of the existing height datums into the new system. This study shows the SIRGAS achievements of the last two years.

  12. School Achievement and Performance in Chilean High Schools: The Mediating Role of Subjective Wellbeing in School-Related Evaluations

    Science.gov (United States)

    López, Verónica; Oyanedel, Juan C.; Bilbao, Marian; Torres, Javier; Oyarzún, Denise; Morales, Macarena; Ascorra, Paula; Carrasco, Claudia

    2017-01-01

    School achievement gaps and school failure are problematic issues in Latin America, and are mainly explained by the socio-economic status (SES) of the students. What schools can do to improve school achievement and reduce school failure is a critical issue, both for school management and teacher training. In this study, we present the association of individual and school-related socio-emotional variables with school achievement and performance, controlling for the effects of SES. A probabilistic sample of 4,964 students, drawn from 191 schools enrolled in year 10 in urban areas of Chile, answered questionnaires assessing subjective wellbeing, social wellbeing in school, school climate, school social wellbeing and students’ perceptions of teachers’ wellbeing. Using structural equation modeling, and controlling for SES, we modeled subjective wellbeing as a mediator of the relationship between school-related variables, such as school climate and perception of teacher’s wellbeing, and (a) school achievement, and (b) school performance. School achievement was computed as a product of (a) the probability of passing the school year, and (b) the percentage of yearly attendance at school. Data on school achievement was drawn from administrative registries from the Chilean Ministry of Education. School performance was computed as the estimated grade point average (GPA) at the end of the school year, based on the students’ previous 5-year GPAs, and was also obtained through administrative data of the last 5 years. Findings reveal the mediating role of subjective wellbeing in the relationship between school-related evaluations (students’ social wellbeing at school, their perception of teachers’ wellbeing and school climate) and school achievement. For school achievement, two variables were mediated (students’ social wellbeing at school and school climate). However, for school performance, no significant mediations were found. We conclude that, on the one hand

  13. School Achievement and Performance in Chilean High Schools: The Mediating Role of Subjective Wellbeing in School-Related Evaluations.

    Science.gov (United States)

    López, Verónica; Oyanedel, Juan C; Bilbao, Marian; Torres, Javier; Oyarzún, Denise; Morales, Macarena; Ascorra, Paula; Carrasco, Claudia

    2017-01-01

    School achievement gaps and school failure are problematic issues in Latin America, and are mainly explained by the socio-economic status (SES) of the students. What schools can do to improve school achievement and reduce school failure is a critical issue, both for school management and teacher training. In this study, we present the association of individual and school-related socio-emotional variables with school achievement and performance, controlling for the effects of SES. A probabilistic sample of 4,964 students, drawn from 191 schools enrolled in year 10 in urban areas of Chile, answered questionnaires assessing subjective wellbeing, social wellbeing in school, school climate, school social wellbeing and students' perceptions of teachers' wellbeing. Using structural equation modeling, and controlling for SES, we modeled subjective wellbeing as a mediator of the relationship between school-related variables, such as school climate and perception of teacher's wellbeing, and (a) school achievement, and (b) school performance. School achievement was computed as a product of (a) the probability of passing the school year, and (b) the percentage of yearly attendance at school. Data on school achievement was drawn from administrative registries from the Chilean Ministry of Education. School performance was computed as the estimated grade point average (GPA) at the end of the school year, based on the students' previous 5-year GPAs, and was also obtained through administrative data of the last 5 years. Findings reveal the mediating role of subjective wellbeing in the relationship between school-related evaluations (students' social wellbeing at school, their perception of teachers' wellbeing and school climate) and school achievement. For school achievement, two variables were mediated (students' social wellbeing at school and school climate). However, for school performance, no significant mediations were found. We conclude that, on the one hand, after

  14. School Achievement and Performance in Chilean High Schools: The Mediating Role of Subjective Wellbeing in School-Related Evaluations

    Directory of Open Access Journals (Sweden)

    Verónica López

    2017-07-01

    Full Text Available School achievement gaps and school failure are problematic issues in Latin America, and are mainly explained by the socio-economic status (SES of the students. What schools can do to improve school achievement and reduce school failure is a critical issue, both for school management and teacher training. In this study, we present the association of individual and school-related socio-emotional variables with school achievement and performance, controlling for the effects of SES. A probabilistic sample of 4,964 students, drawn from 191 schools enrolled in year 10 in urban areas of Chile, answered questionnaires assessing subjective wellbeing, social wellbeing in school, school climate, school social wellbeing and students’ perceptions of teachers’ wellbeing. Using structural equation modeling, and controlling for SES, we modeled subjective wellbeing as a mediator of the relationship between school-related variables, such as school climate and perception of teacher’s wellbeing, and (a school achievement, and (b school performance. School achievement was computed as a product of (a the probability of passing the school year, and (b the percentage of yearly attendance at school. Data on school achievement was drawn from administrative registries from the Chilean Ministry of Education. School performance was computed as the estimated grade point average (GPA at the end of the school year, based on the students’ previous 5-year GPAs, and was also obtained through administrative data of the last 5 years. Findings reveal the mediating role of subjective wellbeing in the relationship between school-related evaluations (students’ social wellbeing at school, their perception of teachers’ wellbeing and school climate and school achievement. For school achievement, two variables were mediated (students’ social wellbeing at school and school climate. However, for school performance, no significant mediations were found. We conclude that, on the

  15. Factors Influencing Junior High School Students’ English Language Achievement in Taiwan: A Bronfenbrenner’s Ecological System Approach

    Directory of Open Access Journals (Sweden)

    Hsin-Yi Kung

    2016-06-01

    Full Text Available This study aimed to construct a social profile of Taiwanese students’ English language achievement by employing Bronfenbrenner’s perspectives. Data were collected on a sample of 709 ninth graders in central Taiwan via survey questionnaires and were analyzed using structural equation modeling. The results indicated that, first, a Taiwanese Students' English Language Achievement model was constructed by parental involvement, teachers’ beliefs/attitudes, parent–teacher interaction, and mass media/the Internet. Second, mass media/the Internet significantly predicted parental involvement and teachers’ beliefs/attitudes; parental involvement and teachers’ beliefs/attitudes significantly predicted students’ English language achievement; the correlation between parental involvement and teachers’ beliefs/attitudes was significant. Third, the completely mediating effects of parental involvement and teachers’ beliefs/attitudes in predicting students’ English language achievement from mass media/the Internet were supported, and the effect of teachers’ beliefs/attitudes tended to be stronger than parental involvement. These findings were in line with Bronfenbrenner’s theory and demonstrate that the influence of the mass media/the Internet (exosystem in students’ English language achievement conveyed the degree of parental involvement (microsystem, teachers’ beliefs/attitudes (microsystem, and the interaction between parents and teachers (mesosystem, especially within the context of the socio-cultural atmosphere in Taiwan (macrosystem. Implications and suggestions were discussed and provided to enhance students’ English language learning.

  16. High-Ability Grouping: Benefits for Gifted Students' Achievement Development Without Costs in Academic Self-Concept.

    Science.gov (United States)

    Preckel, Franzis; Schmidt, Isabelle; Stumpf, Eva; Motschenbacher, Monika; Vogl, Katharina; Scherrer, Vsevolod; Schneider, Wolfgang

    2017-11-23

    Effects of full-time ability grouping on students' academic self-concept (ASC) and mathematics achievement were investigated in the first 3 years of secondary school (four waves of measurement; students' average age at first wave: 10.5 years). Students were primarily from middle and upper class families living in southern Germany. The study sample comprised 148 (60% male) students from 14 gifted classes and 148 (57% male) students from 25 regular classes (matched by propensity score matching). Data analyses involved multilevel and latent growth curve analyses. Findings revealed no evidence for contrast effects of class-average achievement or assimilation effects of class type on students' ASC. ASC remained stable over time. Students in gifted classes showed higher achievement gains than students in regular classes. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

  17. Linear Discriminant Analysis achieves high classification accuracy for the BOLD fMRI response to naturalistic movie stimuli.

    Directory of Open Access Journals (Sweden)

    Hendrik eMandelkow

    2016-03-01

    Full Text Available Naturalistic stimuli like movies evoke complex perceptual processes, which are of great interest in the study of human cognition by functional MRI (fMRI. However, conventional fMRI analysis based on statistical parametric mapping (SPM and the general linear model (GLM is hampered by a lack of accurate parametric models of the BOLD response to complex stimuli. In this situation, statistical machine-learning methods, a.k.a. multivariate pattern analysis (MVPA, have received growing attention for their ability to generate stimulus response models in a data-driven fashion. However, machine-learning methods typically require large amounts of training data as well as computational resources. In the past this has largely limited their application to fMRI experiments involving small sets of stimulus categories and small regions of interest in the brain. By contrast, the present study compares several classification algorithms known as Nearest Neighbour (NN, Gaussian Naïve Bayes (GNB, and (regularised Linear Discriminant Analysis (LDA in terms of their classification accuracy in discriminating the global fMRI response patterns evoked by a large number of naturalistic visual stimuli presented as a movie.Results show that LDA regularised by principal component analysis (PCA achieved high classification accuracies, above 90% on average for single fMRI volumes acquired 2s apart during a 300s movie (chance level 0.7% = 2s/300s. The largest source of classification errors were autocorrelations in the BOLD signal compounded by the similarity of consecutive stimuli. All classifiers performed best when given input features from a large region of interest comprising around 25% of the voxels that responded significantly to the visual stimulus. Consistent with this, the most informative principal components represented widespread distributions of co-activated brain regions that were similar between subjects and may represent functional networks. In light of these

  18. Vocational High School Effectiveness Standard ISO 9001: 2008 for Achievement Content Standards, Standard Process and Competency Standards Graduates

    Directory of Open Access Journals (Sweden)

    Yeni Ratih Pratiwi

    2014-06-01

    Full Text Available Efektivitas Sekolah Menengah Kejuruan Berstandar ISO 9001:2008 terhadap Pencapaian Standar Isi, Standar Proses dan Standar Kompetensi Lulusan Abstract: The purpose of this study was to determine differences in the effectiveness of the achievement of the content standards, process standards, and competency standards in vocational already standard ISO 9001: 2008 with CMS that has not been standardized ISO 9001: 2008 both in public schools and private schools. Data collection using the questionnaire enclosed Likert scale models. Analysis of data using one-way ANOVA using SPSS. The results showed: (1 there is no difference in effectiveness between public SMK ISO standard ISO standards with private SMK (P = 0.001; (2 there are differences in the effectiveness of public SMK SMK ISO standards with ISO standards have not (P = 0.000; (3 there are differences in the effectiveness of public SMK ISO standards with private vocational yet ISO standards (P = 0.000; (4 there are differences in the effectiveness of the private vocational school with vocational standard ISO standard ISO country has not (P = 0.015; (5 there are differences in the effectiveness of the private vocational bertandar ISO with private vocational yet standardized ISO (P = 0.000; (6 there was no difference in the effectiveness of public SMK has not been standardized by the ISO standard ISO private SMK yet. Key Words: vocational high school standards ISO 9001: 2008, the standard content, process standards, competency standards Abstrak: Tujuan penelitian ini untuk mengetahui perbedaan efektivitas pencapaian standar isi, standar proses, dan standar kompetensi lulusan pada SMK yang sudah berstandar ISO 9001:2008 dengan SMK yang belum berstandar ISO 9001:2008 baik pada sekolah negeri maupun sekolah swasta. Pengumpulan data menggunakan kuisioner tertutup model skala likert. Analisis data menggunakan ANOVA one way menggunakan program SPSS. Hasil penelitian menunjukkan: (1 ada perbedaan

  19. Sampling Terrestrial Environments for Bacterial Polyketides

    Directory of Open Access Journals (Sweden)

    Patrick Hill

    2017-04-01

    Full Text Available Bacterial polyketides are highly biologically active molecules that are frequently used as drugs, particularly as antibiotics and anticancer agents, thus the discovery of new polyketides is of major interest. Since the 1980s discovery of polyketides has slowed dramatically due in large part to the repeated rediscovery of known compounds. While recent scientific and technical advances have improved our ability to discover new polyketides, one key area has been under addressed, namely the distribution of polyketide-producing bacteria in the environment. Identifying environments where producing bacteria are abundant and diverse should improve our ability to discover (bioprospect new polyketides. This review summarizes for the bioprospector the state-of-the-field in terrestrial microbial ecology. It provides insight into the scientific and technical challenges limiting the application of microbial ecology discoveries for bioprospecting and summarizes key developments in the field that will enable more effective bioprospecting. The major recent efforts by researchers to sample new environments for polyketide discovery is also reviewed and key emerging environments such as insect associated bacteria, desert soils, disease suppressive soils, and caves are highlighted. Finally strategies for taking and characterizing terrestrial samples to help maximize discovery efforts are proposed and the inclusion of non-actinomycetal bacteria in any terrestrial discovery strategy is recommended.

  20. Utilization of the terrestrial cyanobacteria

    Science.gov (United States)

    Katoh, Hiroshi; Tomita-Yokotani, Kaori; Furukawa, Jun; Kimura, Shunta; Yokoshima, Mika; Yamaguchi, Yuji; Takenaka, Hiroyuki

    The terrestrial, N _{2}-fixing cyanobacterium, Nostoc commune has expected to utilize for agriculture, food and terraforming cause of its extracellular polysaccharide, desiccation tolerance and nitrogen fixation. Previously, the first author indicated that desiccation related genes were analyzed and the suggested that the genes were related to nitrogen fixation and metabolisms. In this report, we suggest possibility of agriculture, using the cyanobacterium. Further, we also found radioactive compounds accumulated N. commune (cyanobacterium) in Fukushima, Japan after nuclear accident. Thus, it is investigated to decontaminate radioactive compounds from the surface soil by the cyanobacterium and showed to accumulate radioactive compounds using the cyanobacterium. We will discuss utilization of terrestrial cyanobacteria under closed environment. Keyword: Desiccation, terrestrial cyanobacteria, bioremediation, agriculture

  1. Efficacy of Tribulus Terrestris Extract on the Serum Glucose and Lipids of Women with Diabetes Mellitus

    Science.gov (United States)

    Samani, Nasrin Babadai; Jokar, Azam; Soveid, Mahmood; Heydari, Mojtaba; Mosavat, Seyed Hamdollah

    2016-01-01

    Background: Considering folkloric use of Tribulus terrestris (T. terrestris) in diabetes and proven anti-hyperglycemic and anti-hyperlipidemic effects of T. terrestris in animal studies, we aimed to evaluate the efficacy of the hydro alcoholic extract of T. terrestris on the serum glucose and lipid profile of women with diabetes mellitus. Methods: Ninety-eight diabetic women were randomly allocated to receive the T. terrestris (1000 mg/day) or placebo for three months. The patients were evaluated in terms of the fasting blood glucose, 2-hour postprandial glucose, glycosylated hemoglobin and lipid profile. Results: T. terrestris showed a significant blood glucose lowering effect in diabetic women compared to placebo (Pterrestris group was significantly reduced compared with placebo, while no significant effect was observed in the triglyceride and high-density lipoprotein levels. Conclusion: This study showed preliminary promising hypoglycemic effect of T. terrestris in diabetic women. PMID:27840471

  2. Efficacy of Tribulus Terrestris Extract on the Serum Glucose and Lipids of Women with Diabetes Mellitus.

    Science.gov (United States)

    Samani, Nasrin Babadai; Jokar, Azam; Soveid, Mahmood; Heydari, Mojtaba; Mosavat, Seyed Hamdollah

    2016-05-01

    Considering folkloric use of Tribulus terrestris (T. terrestris) in diabetes and proven anti-hyperglycemic and anti-hyperlipidemic effects of T. terrestris in animal studies, we aimed to evaluate the efficacy of the hydro alcoholic extract of T. terrestris on the serum glucose and lipid profile of women with diabetes mellitus. Ninety-eight diabetic women were randomly allocated to receive the T. terrestris (1000 mg/day) or placebo for three months. The patients were evaluated in terms of the fasting blood glucose, 2-hour postprandial glucose, glycosylated hemoglobin and lipid profile. T. terrestris showed a significant blood glucose lowering effect in diabetic women compared to placebo (Pterrestris group was significantly reduced compared with placebo, while no significant effect was observed in the triglyceride and high-density lipoprotein levels. This study showed preliminary promising hypoglycemic effect of T. terrestris in diabetic women.

  3. Working Memory Load and Reminder Effect on Event-Based Prospective Memory of High- and Low-Achieving Students in Math

    Science.gov (United States)

    Chen, Youzhen; Lian, Rong; Yang, Lixian; Liu, Jianrong; Meng, Yingfang

    2017-01-01

    The effects of working memory (WM) demand and reminders on an event-based prospective memory (PM) task were compared between students with low and high achievement in math. WM load (1- and 2-back tasks) was manipulated as a within-subject factor and reminder (with or without reminder) as a between-subject factor. Results showed that high-achieving…

  4. Examination of Science and Math Course Achievements of Vocational High School Students in the Scope of Self-Efficacy and Anxiety

    Science.gov (United States)

    Yüksel, Mehmet; Geban, Ömer

    2016-01-01

    This study attempted to predict physics, chemistry, and biology and math course achievements of vocational high school students according to the variables of student self-efficacy, academic self-efficacy, state anxiety and trait anxiety. Study data were collected using a questionnaire administered to the students of a vocational high school…

  5. Investigation of Academic Procrastination Prevalence and Its Relationship with Academic Self-Regulation and Achievement Motivation among High-School Students in Tehran City

    Science.gov (United States)

    Ebadi, Setareh; Shakoorzadeh, Reza

    2015-01-01

    The present study was carried out with the aim of Investigation of academic procrastination prevalence and its relationship with academic self-regulation and achievement motivation among high-school students in Tehran city. The sample included 624 high school students (312 Boys & 312 Girls) from different areas and regions that selected using…

  6. Advective and diffusive dermal processes for estimating terrestrial amphibian pesticide exposure

    Science.gov (United States)

    Background/Question/Methods Dermal exposure presents a potentially significant but understudied route for pesticide uptake in terrestrial amphibians. Historically, evaluation of pesticide risk to both amphibians and reptiles has been achieved by comparing ingestion and inhalat...

  7. Testing the Digital Divide: Does Access to High-Quality Use of Technology in Schools Affect Student Achievement?

    Science.gov (United States)

    Talley, Gregory Keith

    2012-01-01

    This study investigates the relationship between access, use of technology and student achievement in public middle schools in Maryland. The objective of this study was to determine whether a digital divide (differences in access and utilization of technology based on student characteristics of race, socioeconomic status, and gender) exists among…

  8. Examining the Impact of Acculturation and Perceived Social Support on Mathematics Achievement among Latino/a High School Students

    Science.gov (United States)

    Neseth, Hans; Savage, Todd A.; Navarro, Rachel

    2009-01-01

    The current migration of Latino/as into the United States has many schools struggling to meet the unique academic needs of this particular group of students. Previous research suggests level of acculturation and perceived social support impact mathematics achievement amongst Latino/a students. The current study employed hierarchical and…

  9. The Relationship between Self-Esteem and Academic Achievement in High Ability Students: Evidence from the Wollongong Youth Study

    Science.gov (United States)

    Vialle, Wilma; Heaven, Patrick C. L.; Ciarrochi, Joseph

    2015-01-01

    The relationship between self-esteem and academic achievement is one that is regarded by many educators as a well-established fact. This belief has been often invoked in order to argue against the provision of ability grouping for gifted students. Refuting that commonly-held belief, this research examined the relationship between self-esteem and…

  10. Academic Attitudes and Achievement in Students of Urban Public Single-Sex and Mixed-Sex High Schools

    Science.gov (United States)

    Else-Quest, Nicole M.; Peterca, Oana

    2015-01-01

    Publicly funded single-sex schooling (SSS) has proliferated in recent years and is touted as a remedy to gaps in academic attitudes and achievement, particularly for low-income students of color. Research on SSS is rife with limitations, stemming from selective admissions processes, selection effects related to socioeconomic status, a lack of…

  11. The Impact of Every Classroom, Every Day on High School Student Achievement: Results from a School-Randomized Trial

    Science.gov (United States)

    Early, Diane M.; Berg, Juliette K.; Alicea, Stacey; Si, Yajuan; Aber, J. Lawrence; Ryan, Richard M.; Deci, Edward L.

    2016-01-01

    Every Classroom, Every Day (ECED) is a set of instructional improvement interventions designed to increase student achievement in math and English/language arts (ELA). ECED includes three primary components: (a) systematic classroom observations by school leaders, (b) intensive professional development and support for math teachers and…

  12. Targeted Funding for Educationally Disadvantaged Students: A Regression Discontinuity Estimate of the Impact on High School Student Achievement

    Science.gov (United States)

    Henry, Gary T.; Fortner, C. Kevin; Thompson, Charles L.

    2010-01-01

    Evaluating the impacts of public school funding on student achievement has been an important objective for informing education policymaking but fraught with data and methodological limitations. Findings from prior research have been mixed at best, leaving policymakers with little advice about the benefits of allocating public resources to schools…

  13. Do Children's Executive Functions Account for Associations between Early Autonomy-Supportive Parenting and Achievement through High School?

    Science.gov (United States)

    Bindman, Samantha W.; Pomerantz, Eva M.; Roisman, Glenn I.

    2015-01-01

    This study evaluated whether the positive association between early autonomy-supportive parenting and children's subsequent achievement is mediated by children's executive functions. Using observations of mothers' parenting from the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development (N…

  14. The Impact of Higher Expectations in Math on the Perception of Achievement of High School Students with Disabilities

    Science.gov (United States)

    Przybylinski, Vincent S., Jr.

    2016-01-01

    There exists a dearth of research on strategies that will help students with disabilities gain greater access to standards-based mathematics and close the mathematics achievement gap between general education students and students with disabilities (Browder et al., 2012; Jitendra, 2013; van Garderen, Scheuermann, Jackson, & Hampton, 2009).…

  15. Relationships between Time-Management Skills, Facebook Interpersonal Skills and Academic Achievement among Junior High School Students

    Science.gov (United States)

    Tsai, Hsien-Chang; Liu, Shih-Hsiung

    2015-01-01

    Effective time-management skills and interpersonal interactions with familiar friends for learning matters on Facebook are desired characteristics for adolescents attempting to improve their academic achievements. This study identifies the relationships between time-management skills and Facebook interpersonal skills with the academic achievement…

  16. Recognizing Internet Addiction: Prevalence and Relationship to Academic Achievement in Adolescents Enrolled in Urban and Rural Greek High Schools

    Science.gov (United States)

    Stavropoulos, Vasilis; Alexandraki, Kiriaki; Motti-Stefanidi, Frosso

    2013-01-01

    This study aims: a) to estimate the prevalence of internet addiction among adolescents of urban and rural areas in Greece, b) to examine whether the Internet Addiction Test cut-off point is applicable to them and c) to investigate the phenomenon's association with academic achievement. Participants were 2090 adolescents (mean age 16, 1036 males,…

  17. Influences on Academic Achievement Across High and Low Income Countries: A Re-Analysis of IEA Data.

    Science.gov (United States)

    Heyneman, S.; Loxley, W.

    Previous international studies of science achievement put the data through a process of winnowing to decide which variables to keep in the final regressions. Variables were allowed to enter the final regressions if they met a minimum beta coefficient criterion of 0.05 averaged across rich and poor countries alike. The criterion was an average…

  18. Soil and terrestrial biology studies

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Soil and terrestrial biology studies focused on developing an understanding of the uptake of gaseous substances from the atmosphere by plants, biodegradation of oil, and the movement of Pu in the terrestrial ecosystems of the southeastern United States. Mathematical models were developed for SO 2 and tritium uptake from the atmosphere by plants; the uptake of tritium by soil microorganisms was measured; and the relationships among the Pu content of soil, plants, and animals of the Savannah River Plant area were studied. Preliminary results are reported for studies on the biodegradation of waste oil on soil surfaces

  19. Priapism caused by 'Tribulus terrestris'.

    Science.gov (United States)

    Campanelli, M; De Thomasis, R; Tenaglia, R L

    2016-01-01

    A 36-year-old Caucasian man was diagnosed with a 72-h-lasting priapism that occurred after the assumption of a Herbal supplement based on Tribulus terrestris, which is becoming increasingly popular for the treatment of sexual dysfunction. The patient underwent a cavernoglandular shunt (Ebbehoj shunt) in order to obtain complete detumescence, from which derived negative post-episode outcomes on sexual function. All patients consuming non-FDA-approved alternative supplements such as Tribulus terrestris should be warned about the possible serious side effects.

  20. Novel viral genomes identified from six metagenomes reveal wide distribution of archaeal viruses and high viral diversity in terrestrial hot springs

    DEFF Research Database (Denmark)

    Islin, Sóley Ruth; Menzel, Peter; Krogh, Anders

    2016-01-01

    Limited by culture-dependent methods the number of viruses identified from thermophilic Archaea and Bacteria is still very small. In this study we retrieved viral sequences from six hot spring metagenomes isolated worldwide, revealing a wide distribution of four archaeal viral families....... Among the novel genomes, one belongs to a putative thermophilic virus infecting the bacterium Hydrogenobaculum, for which no virus has been reported in the literature. Moreover, a high viral diversity was observed in the metagenomes, especially among the Lipothrixviridae, as indicated by the large...

  1. UAS CNPC Satellite Link Performance - Sharing Spectrum with Terrestrial Systems

    Science.gov (United States)

    Kerczewski, Robert J.; Wilson, Jeffrey D.; Bishop, William D.

    2016-01-01

    In order to provide for the safe integration of unmanned aircraft systems into the National Airspace System, the control and non-payload communications (CNPC) link connecting the ground-based pilot with the unmanned aircraft must be highly reliable. A specific requirement is that it must operate using aviation safety radiofrequency spectrum. The 2012 World Radiocommunication Conference (WRC-12) provided a potentially suitable allocation for radio line-of-sight (LOS), terrestrial based CNPC link at 5030-5091 MHz. For a beyond radio line-of-sight (BLOS), satellite-based CNPC link, aviation safety spectrum allocations are currently inadequate. Therefore, the 2015 WRC will consider the use of Fixed Satellite Service (FSS) bands to provide BLOS CNPC under Agenda Item 1.5. This agenda item requires studies to be conducted to allow for the consideration of how unmanned aircraft can employ FSS for BLOS CNPC while maintaining existing systems. Since there are terrestrial Fixed Service systems also using the same frequency bands under consideration in Agenda Item 1.5 one of the studies required considered spectrum sharing between earth stations on-board unmanned aircraft and Fixed Service station receivers. Studies carried out by NASA have concluded that such sharing is possible under parameters previously established by the International Telecommunications Union. As the preparation for WRC-15 has progressed, additional study parameters Agenda Item 1.5 have been proposed, and some studies using these parameters have been added. This paper examines the study results for the original parameters as well as results considering some of the more recently proposed parameters to provide insight into the complicated process of resolving WRC-15 Agenda Item 1.5 and achieving a solution for BLOS CNPC for unmanned aircraft.

  2. Calibrating Late Cretaceous Terrestrial Cyclostratigraphy with High-precision U-Pb Zircon Geochronology: Qingshankou Formation of the Songliao Basin, China

    Science.gov (United States)

    Wang, T.; Ramezani, J.; Wang, C.

    2015-12-01

    A continuous succession of Late Cretaceous lacustrine strata has been recovered from the SK-I south (SK-Is) and SKI north (SK-In) boreholes in the long-lived Cretaceous Songliao Basin in Northeast China. Establishing a high-resolution chronostratigraphic framework is a prerequisite for integrating the Songliao record with the global marine Cretaceous. We present high-precision U-Pb zircon geochronology by the chemical abrasion isotope dilution thermal-ionization mass spectrometry method from multiple bentonite core samples from the Late Cretaceous Qingshankou Formation in order to assess the astrochronological model for the Songliao Basin cyclostratigraphy. Our results from the SK-Is core present major improvements in precision and accuracy over the previously published geochronology and allow a cycle-level calibration of the cyclostratigraphy. The resulting choronostratigraphy suggest a good first-order agreement between the radioisotope geochronology and the established astrochronological time scale over the corresponding interval. The dated bentonite beds near the 1780 m depth straddle a prominent oil shale layer of the Qingshankou Formation, which records a basin-wide lake anoxic event (LAE1), providing a direct age constraint for the LAE1. The latter appears to coincide in time with the Late Cretaceous (Turonian) global sea level change event Tu4 presently constrained at 91.8 Ma.

  3. Mercury in terrestrial forested systems with highly elevated mercury deposition in southwestern China: The risk to insects and potential release from wildfires

    International Nuclear Information System (INIS)

    Zhou, Jun; Wang, Zhangwei; Sun, Ting; Zhang, Huan; Zhang, Xiaoshan

    2016-01-01

    Forests are considered a pool of mercury in the global mercury cycle. However, few studies have investigated the distribution of mercury in the forested systems in China. Tieshanping forest catchment in southwest China was impacted by mercury emissions from industrial activities and coal combustions. Our work studied mercury content in atmosphere, soil, vegetation and insect with a view to estimating the potential for mercury release during forest fires. Results of the present study showed that total gaseous mercury (TGM) was highly elevated and the annual mean concentration was 3.51 ± 1.39 ng m"−"2. Of the vegetation tissues, the mercury concentration follows the order of leaf/needle > root > bark > branch > bole wood for each species. Total ecosystem mercury pool was 103.5 mg m"−"2 and about 99.4% of the mercury resides in soil layers (0–40 cm). The remaining 0.6% (0.50 mg m"−"2) of mercury was stored in biomass. The large mercury stocks in the forest ecosystem pose a serious threat for large pluses to the atmospheric mercury during potential wildfires and additional ecological stress to forest insect: dung beetles, cicada and longicorn, with mercury concentration of 1983 ± 446, 49 ± 38 and 7 ± 5 ng g"−"1, respectively. Hence, the results obtained in the present study has implications for global estimates of mercury storage in forests, risks to forest insect and potential release to the atmosphere during wildfires. - Highlights: • Mercury in air, soil, biomass and insect were studied at a subtropical forest. • 99.4% of the total ecosystem mercury pools was resided in soil layers. • High mercury pools were large pulses to the atmosphere during potential wildfires. • High mercury deposition in forest pose an ecological stress to insect. - Large mercury pools in forest pose a serious threat for large pluses to the atmospheric mercury during potential wildfires and ecological stress to insect.

  4. Preliminary assessment of terrestrial microalgae isolated from lichens as testing species for environmental monitoring: lichen phycobionts present high sensitivity to environmental micropollutants.

    Science.gov (United States)

    Domínguez-Morueco, N; Moreno, H; Barreno, E; Catalá, M

    2014-01-01

    Bioassays constitute a tool for pollution analysis providing a holistic approach and high-quality indication of the toxicity. Microbioassays allow evaluating the toxicity of many samples, implying lower costs and enabling routine monitoring and pollution control. But tests conducted so far are limited to the use of a small number of taxa. Lichens are excellent bioindicators of pollution with great ecological significance. Studies show that the phycobiont is more sensitive to pollutants than the mycobiont. Phycobiont have features such as adaptation to anhydrobiosis and relatively rapid growth in vitro, making them suitable for microbioassays. Our aim is to determine the sensitivity of phycobionts to the pharmaceutical micropollutants carbamazepine and diclofenac as a preliminary step for the development of a toxicity microbioassay based on phycobionts. Optical dispersion and chlorophyll autofluorescence were used as endpoints of toxicity on two algal species showing that suspensions present cyclic and taxon specific patterns of aggregation. Trebouxia TR9 suspensions present a very high grade of aggregation while Asterochloris erici cells do not. Both micropollutants alter optical properties of the suspensions of both species. No significant alteration of chlorophyll autofluorescence by carbamazepine is observed. A. erici chlorophyll autofluorescence is extremely sensitive to diclofenac but the effect is not dependent on the drug concentration or on the time of exposure. Differently, TR9 only shows punctual chlorophyll alterations. Fluctuations in optical dispersion may indicate changes in the population structure of the species, including reproductive strategy. A. erici seems more sensitive to micropollutants, is better characterized and is available from commercial collections. © 2013 Published by Elsevier Inc.

  5. Magnetic storm injection of 0.9- to 16-keV/e solar and terrestrial ions into the high-altitude magnetosphere

    International Nuclear Information System (INIS)

    Balsiger, H.; Eberhardt, P.; Geiss, J.; Young, D.T.

    1980-01-01

    The Geos 1 ion composition experiments has surveyed the plasma composition in the energy per charge range below 16 keV/e at all local times and at L=3--8. During quiet and moderately disturbed times, H + is the dominant species with a few percent of heavy (M/Q>1) ions. Substorms and storms increase the relative amount of heavy ions, and occasionally, they can become the dominant species in the outer magnetosphere. Two sources, the solar wind (characterized by 4 He ++ ) and the ionosphere (characterized by O + ), give on the average comparable contributions to storm time plasma, although in individual storms one or the other may dominate. Data presented here suggest that high-altitude thermal plasma or the plasmasphere (characterized by He + and O ++ ) must be considered as a third source. Under storm conditions with Geos in the dawn-noon local time sector we have observed a mixed composition region just inside the magnetopause where high fluxes of H + , He ++ , O + , and occasionally He + ions are present. During several storms a composition profile could be measured down to Lapprox.3. Both O + and He + increase toward low altitudes, and O + (within our energy range) can become dominant at the inner edge of the ring current. On April 30, 1978, during a storm, O + contributed > or approx. =8% to the total local energy density of the ring current particles at L=4.1. In no storm has He + been observed to be the main constituent during the recovery phase. During storm recovery, H + and O + are the dominant ions, the H + /O + ratio remaining constant or even increasing during the days following the main phase of the storms. This suggests that charge exchange is not the only loss mechanism for the storm time ring current and/or that H + is replenished during the recovery phase

  6. Fermi GBM Observations of Terrestrial Gamma Flashes

    Science.gov (United States)

    Wilson-Hodge, Colleen A.; Briggs, M. S.; Connaughton, V.; Fishman, G. J.; Bhat, P. N.; Paciesas, W. S.; Preece, R. D.; Kippen, R. M.; vonKienlin, A.; Dwyer, J. R.; hide

    2010-01-01

    In its first two years of operation, the Fermi Gamma Ray Burst Monitor (GBM) has observed 79 Terrestrial Gamma Flashes (TGFs). The thick Bismuth Germanate (BGO) detectors are excellent for TGF spectroscopy, having a high probability of recording the full energy of an incident photon, spanning a broad energy range from 150 keV to 40 MeV, and recording a large number of photons per TGF. Correlations between GBM TGF triggers and lightning sferics detected with the World-Wide Lightning Location Network indicate that TGFs and lightning are simultaneous to within tens of microseconds.

  7. The relationship between psychological adjustment and social protection with academic self-concept and academic achievement among high school female students in Rasht

    Directory of Open Access Journals (Sweden)

    Kobra Dadarigashti

    2016-07-01

    Full Text Available The study conducted to examine the relationship between psychological adjustment and social protection with academic self-concept and academic achievement among high school female students in Rasht. The research is descriptive correlational. The target population includes all female students studying in Rasht in 2015. By random cluster sampling method and based on the variables, 180 subjects selected. In this study, to collect data, psychological adjustment and social support, academic self-concept and academic achievement questionnaire are used. To test the hypothesis of this research, the parametric statistical Pearson correlation and regression tests are used. Moreover, all statistical operations were analyzed by using SPSS software. The research results showed that the correlation values between psychological adjustment and social support with academic self-concept and academic achievement of high school female students is statistically significant ( 01/0 > p.

  8. The Planetary Terrestrial Analogues Library (PTAL)

    Science.gov (United States)

    Werner, S. C.; Dypvik, H.; Poulet, F.; Rull Perez, F.; Bibring, J.-P.; Bultel, B.; Casanova Roque, C.; Carter, J.; Cousin, A.; Guzman, A.; Hamm, V.; Hellevang, H.; Lantz, C.; Lopez-Reyes, G.; Manrique, J. A.; Maurice, S.; Medina Garcia, J.; Navarro, R.; Negro, J. I.; Neumann, E. R.; Pilorget, C.; Riu, L.; Sætre, C.; Sansano Caramazana, A.; Sanz Arranz, A.; Sobron Grañón, F.; Veneranda, M.; Viennet, J.-C.; PTAL Team

    2018-04-01

    The Planetary Terrestrial Analogues Library project aims to build and exploit a spectral data base for the characterisation of the mineralogical and geological evolution of terrestrial planets and small solar system bodies.

  9. Terrestrial Steering Group. 2014. Arctic Terrestrial Biodiversity Monitoring Plan

    DEFF Research Database (Denmark)

    Aastrup, Peter; Aronsson, Mora; Barry, Tom

    capacity and information may be currently available and (b) to outline near-term required steps to begin implementing the plan and reporting on an initial set of Arctic terrestrial biodiversity focal ecosystem component attributes. The specific objectives of the workshop were to: Identify key products...... for TSG for the next two years. Identify key components of a pan-Arctic status report for priority focal ecosystem components (FEC) attributes for policy and decision makers. Develop a prioritized set of activities to meet reporting objectives. Identify key milestones and timelines for the successful...... implementation of the Arctic Terrestrial Biodiversity Monitoring Plan for the next two years. Identify expert networks required for successful implementation of the plan. Identify key gaps and opportunities for the TSG related to plan implementation and identify near-term next steps to address gaps....

  10. Self-regulatory mode (locomotion and assessment), well-being (subjective and psychological), and exercise behavior (frequency and intensity) in relation to high school pupils' academic achievement.

    Science.gov (United States)

    Garcia, Danilo; Jimmefors, Alexander; Mousavi, Fariba; Adrianson, Lillemor; Rosenberg, Patricia; Archer, Trevor

    2015-01-01

    Background. Self-regulation is the procedure implemented by an individual striving to reach a goal and consists of two inter-related strategies: assessment and locomotion. Moreover, both subjective and psychological well-being along exercise behaviour might also play a role on adolescents academic achievement. Method. Participants were 160 Swedish high school pupils (111 boys and 49 girls) with an age mean of 17.74 (sd = 1.29). We used the Regulatory Mode Questionnaire to measure self-regulation strategies (i.e., locomotion and assessment). Well-being was measured using Ryff's Psychological Well-Being Scales short version, the Temporal Satisfaction with Life Scale, and the Positive Affect and Negative Affect Schedule. Exercise behaviour was self-reported using questions pertaining to frequency and intensity of exercise compliance. Academic achievement was operationalized through the pupils' mean value of final grades in Swedish, Mathematics, English, and Physical Education. Both correlation and regressions analyses were conducted. Results. Academic achievement was positively related to assessment, well-being, and frequent/intensive exercise behaviour. Assessment was, however, negatively related to well-being. Locomotion on the other hand was positively associated to well-being and also to exercise behaviour. Conclusions. The results suggest a dual (in)direct model to increase pupils' academic achievement and well-being-assessment being directly related to higher academic achievement, while locomotion is related to frequently exercising and well-being, which in turn, increase academic achievement.

  11. Understanding the factors that influence high science achievers' academic choices and intent to pursue or opt out of the hard sciences

    Science.gov (United States)

    Quihuis, Gisell

    Drawing on Eccles and her colleagues' Expectancy-Value model of academic behavior and choice, this dissertation study set out to serve three purposes: (1) to understand how high achieving high school students who aspire to science college degrees compare, in terms of motivational beliefs and social experiences, with other high achievers who do not aspire to science college degrees; (2) to understand why some high school students who excel in the hard sciences are unsure about pursuing a science degree in college; and (3) to examine whether gender differences in motivational beliefs and social experiences found in previous research on math (see Eccles 1984) exist for science among high achieving high school students. Survey and interview data showed that gender differences previously found in Eccles' research on math exist for science among a select group of high achieving high school students. Yet, these gender differences did not explain students' aspirations for science. Motivation, classroom perceptions, science engagement, as well as other science-related experiences at home and school, including parent and teacher influences, were also important factors associated with students' aspirations for science. Results and implications for this study are encouraging because they suggest that both parents and educators can help more high achievers become interested in science. Parents can expose their children, male and female alike, to science at home early on in their childhood and teachers can help students sustain and further develop an interest in science at school. In this manner, both parents and teachers can work together as a team to encourage more high achievers to aspire to science degrees in their future. Lastly, it is important to note that this study found Eccles' model of motivation and choice helpful in understanding not only gender differences in math and the hard sciences, but also aspiration differences that cut across gender among students

  12. Does Self-Regulated Learning-Skills Training Improve High-School Students' Self-Regulation, Math Achievement, and Motivation While Using an Intelligent Tutor?

    Science.gov (United States)

    Barrus, Angela

    2013-01-01

    This study empirically evaluated the effectiveness of the instructional design, learning tools, and role of the teacher in three versions of a semester-long, high-school remedial Algebra I course to determine what impact self-regulated learning skills and learning pattern training have on students' self-regulation, math achievement, and…

  13. Teachers' Autonomy Support, Autonomy Suppression and Conditional Negative Regard as Predictors of Optimal Learning Experience among High-Achieving Bedouin Students

    Science.gov (United States)

    Kaplan, Haya

    2018-01-01

    The study is based on self-determination theory and focuses on the motivation of high-achieving Bedouin students who belong to a hierarchical-collectivist society. The study focuses on the question: What are the relations between teachers' autonomy support and control and an optimal learning experience among students? The study is unique in its…

  14. Is Blended e-Learning as Measured by an Achievement Test and Self-Assessment Better than Traditional Classroom Learning for Vocational High School Students?

    Science.gov (United States)

    Chang, Chi-Cheng; Shu, Kuen-Ming; Liang, Chaoyun; Tseng, Ju-Shih; Hsu, Yu-Sheng

    2014-01-01

    The purpose of this study is to examine the effects of blended e-learning on electrical machinery performance (achievement test and self-assessment). Participants were two classes of 11th graders majoring in electrical engineering and taking the electrical machinery class at a vocational high school in Taiwan. The participants were randomly…

  15. An Examination of the Influence of Self Efficacy, Locus of Control, and Perceptions of Parent Involvement on Academic Achievement of Urban High School Students

    Science.gov (United States)

    Myree, Claudia

    2011-01-01

    Current research indicates that there is an on-going concern for the graduation rate of African American students in urban settings. This particular study sought to investigate the impact of students' self-efficacy, locus of control, and parental involvement on academic achievement via a targeted sample of urban African American high school…

  16. Effect of Feedback Strategy and Motivation of Achievement to Improving Learning Results Concept in Learning Civic Education in Vocational High School

    Science.gov (United States)

    Sumarno; Setyosari, Punaji; Haryono

    2017-01-01

    This study aims to examine the effect of feedback strategies on understanding and applying the concept of National ideology to students who have different achievement motivation, on learning Citizenship Education in vocational high schools. This research uses quasi experiment research design (Quasi Experiment). The subjects of this study were 133…

  17. Life Satisfaction among Highly Achieving Students in Hong Kong: Do Gratitude and the "Good-Enough Mindset" Add to the Contribution of Perfectionism in Prediction?

    Science.gov (United States)

    Chan, David W.

    2012-01-01

    This study investigated whether gratitude and the "good-enough mindset" added to the contribution of perfectionism in predicting life satisfaction in 245 Chinese highly achieving students in Hong Kong. Participants completed self-report questionnaires that included scales on life satisfaction, positive and negative perfectionism…

  18. Relations among Academic Enablers and Academic Achievement in Children with and without High Levels of Parent-Rated Symptoms of Inattention, Impulsivity, and Hyperactivity

    Science.gov (United States)

    Demaray, Michelle Kilpatrick; Jenkins, Lyndsay N.

    2011-01-01

    This study examined the relationships among academic enablers (i.e., engagement, interpersonal skills, motivation, study skills) and academic achievement in children with and without high levels of parent-rated symptoms of inattention, impulsivity, and hyperactivity (Symptoms of IIH Group). The study included 69 participants (29 [42%] in the IIH…

  19. How Does the Science Writing Heuristic Approach Affect Students' Performances of Different Academic Achievement Levels? A Case for High School Chemistry

    Science.gov (United States)

    Kingir, Sevgi; Geban, Omer; Gunel, Murat

    2012-01-01

    This study investigates the effects of the Science Writing Heuristic (SWH), known as an argumentation-based science inquiry approach, on Grade 9 students' performance on a post-test in relation to their academic achievement levels. Four intact classes taught by 2 chemistry teachers from a Turkish public high school were selected for the study; one…

  20. The Transition from Single-Sex to Coeducational High Schools: Effects on Multiple Dimensions of Self-Concept and on Academic Achievement.

    Science.gov (United States)

    Marsh, Herbert W.; And Others

    1988-01-01

    Self-concept measures and state certificate program achievement grades were used to determine the effects on 7th through 11th graders in Sydney (Australia) of converting two single-sex high schools to coeducational institutions. Pre- to post-transition data were collected from 1982 to 1985. Coeducational organizations benefit self-concept, while…

  1. Radiative heat transfer enhancement using geometric and spectral control for achieving high-efficiency solar-thermophotovoltaic systems

    Science.gov (United States)

    Kohiyama, Asaka; Shimizu, Makoto; Yugami, Hiroo

    2018-04-01

    We numerically investigate radiative heat transfer enhancement using spectral and geometric control of the absorber/emitter. A high extraction of the radiative heat transfer from the emitter as well as minimization of the optical losses from the absorber leads to high extraction and solar thermophotovoltaic (STPV) system efficiency. The important points for high-efficiency STPV design are discussed for the low and high area ratio of the absorber/emitter. The obtained general guideline will support the design of various types of STPV systems.

  2. Constitution of terrestrial planets

    International Nuclear Information System (INIS)

    Waenke, H.

    1981-01-01

    Reliable estimates of the bulk composition are restricted to the Earth, the Moon and the eucrite parent asteroid. The last, the parent body of the eucrite-diogenite family of meteorites, seems to have an almost chondritic composition except for a considerable depletion of all moderately volatile (Na, K, Rb, F, etc.) and highly volatile (Cl, Br, Cd, Pb, etc.) elements. The moon is also depleted in moderate volatile and volatile elements compared to carbonaceous chondrites of type 1 (C1) and to the Earth. Again normalized to C1 and Si the Earth's mantle and the Moon are slightly enriched in refractory lithophile elements and in magnesium. The striking depletion of the Earth's mantle for the elements V, Cr and Mn can be explained by their partial removal into the core. Apart from their contents of metallic iron, all siderophile elements, moderately volatile and volatile elements, Earth and Moon are chemically very similar. It might well be that, with these exceptions and that of a varying degree of oxidation, all the inner planets have a similar chemistry. The chemical composition of the Earth's mantle, yields important information about the accretion history of the Earth and that of the inner planets. (author)

  3. Bio-inspired Ni2+-polyphenol hydrophilic network to achieve unconventional high-flux nanofiltration membranes for environmental remediation.

    Science.gov (United States)

    You, Fangjie; Xu, Yanchao; Yang, Xiaobin; Zhang, Yanqiu; Shao, Lu

    2017-06-01

    A novel Ni 2+ -polyphenol network was designed as an excellent bio-coating by a one-step strategy to obtain nanofiltration membranes, possessing unconventional high water flux up to 56.1 L m -2 h -1 bar -1 with rose bengal (RB) rejection above 95%. This study provides a facile approach to prepare highly-efficient nanofiltration membranes for wastewater remediation.

  4. High- and Low-Achieving Fraternity Environments at a Selective Institution: Their Influence on Members' Binge Drinking and GPA

    Science.gov (United States)

    Maholchic-Nelson, Suzy

    2010-01-01

    This correlational study tested the efficacy of the social-ecological theory (Moos, 1979) by employing the University Residential Environmental Scale and multiple regression analysis to examine the influences of personal attributes (SAT, parents' level of education, race/ethnicity, and high school drinking) and environmental factors (high/low…

  5. Measuring What High-Achieving Students Know and Can Do on Entry to School: PIPS 2002-2008

    Science.gov (United States)

    Wildy, Helen; Styles, Irene

    2011-01-01

    Anecdotal evidence from teachers in Western Australia suggested that increasing numbers of on-entry students have been performing at high levels over recent years on the Performance Indicators in Primary Schools Baseline Assessment (PIPS-BLA). This paper reports the results of an investigation into the performance of high-scoring students. Data…

  6. The function of androgen/androgen receptor and insulin growth factor‑1/insulin growth factor‑1 receptor on the effects of Tribulus terrestris extracts in rats undergoing high intensity exercise.

    Science.gov (United States)

    Wu, Yin; Yang, Hongfang; Wang, Xiaohui

    2017-09-01

    Our previous study demonstrated that treatment with Tribulus terrestris (TT) extracts (120 mg/kg) promoted the muscle weight gain and performance of rats undergoing high intensity exercise. The present study was designed to explore the mechanisms underlying the effect of treatment with TT extracts and the involvement of androgens, the androgen receptor (AR), insulin growth factor‑1 (IGF‑1) and the IGF‑1 receptor (IGF‑1R). A total of 32 Sprague‑Dawley rats were randomly divided into groups as follows: Control; TT, treated with TT extracts, E, high intensity exercise; E+TT, high intensity exercise plus TT treatment. The rats of the E and E+TT groups underwent high intensity exercise with a progressively increasing load for 5 weeks, and TT extracts were intragastrically administered in the TT and E+TT rats 30 min prior to training. TT extract composition was analyzed using ultra‑high performance liquid chromatography‑quadrupole‑time of flight mass spectrometry. Testosterone and IGF‑1 plasma levels and AR, IGF‑1R and myosin heavy chain (MHC) protein levels in muscles were determined by ELISA and western blotting, respectively. The saponins tigogenin and diosgenin comprised ~71.35% of the total peak area. Compared with the E group, TT extracts increased the testosterone and IGF‑1 plasma levels, and AR, IGF‑1R and MHC protein levels in the gastrocnemius of rats undergoing high intensity exercise, accompanied with increased body weight and gastrocnemius weight. In conclusion, the effect of TT extracts on the performance of high intensity exercise rats may be attributed to increased levels of circulating testosterone and IGF‑1 and increased AR and IGF‑1R protein expression levels in the gastrocnemius, resulting in increased muscle weight and increased MHC in the gastrocnemius. The present study provided preliminary evidence supporting the use of TT extracts as a dietary supplement for the promotion of skeletal muscle mass increase and the

  7. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2011-01-01

    Most people think of groundwater as a resource, but it is also a useful indicator of climate variability and human impacts on the environment. Groundwater storage varies slowly relative to other non-frozen components of the water cycle, encapsulating long period variations and trends in surface meteorology. On seasonal to interannual timescales, groundwater is as dynamic as soil moisture, and it has been shown that groundwater storage changes have contributed to sea level variations. Groundwater monitoring well measurements are too sporadic and poorly assembled outside of the United States and a few other nations to permit direct global assessment of groundwater variability. However, observational estimates of terrestrial water storage (TWS) variations from the GRACE satellites largely represent groundwater storage variations on an interannual basis, save for high latitude/altitude (dominated by snow and ice) and wet tropical (surface water) regions. A figure maps changes in mean annual TWS from 2009 to 2010, based on GRACE, reflecting hydroclimatic conditions in 2010. Severe droughts impacted Russia and the Amazon, and drier than normal weather also affected the Indochinese peninsula, parts of central and southern Africa, and western Australia. Groundwater depletion continued in northern India, while heavy rains in California helped to replenish aquifers that have been depleted by drought and withdrawals for irrigation, though they are still below normal levels. Droughts in northern Argentina and western China similarly abated. Wet weather raised aquifer levels broadly across western Europe. Rains in eastern Australia caused flooding to the north and helped to mitigate a decade long drought in the south. Significant reductions in TWS seen in the coast of Alaska and the Patagonian Andes represent ongoing glacier melt, not groundwater depletion. Figures plot time series of zonal mean and global GRACE derived non-seasonal TWS anomalies (deviation from the mean of

  8. Achievement of high diode sensitivity via spin torque-induced resonant expulsion in vortex magnetic tunnel junction

    Science.gov (United States)

    Tsunegi, Sumito; Taniguchi, Tomohiro; Yakushiji, Kay; Fukushima, Akio; Yuasa, Shinji; Kubota, Hitoshi

    2018-05-01

    We investigated the spin-torque diode effect in a magnetic tunnel junction with FeB free layer. Vortex-core expulsion was observed near the boundary between vortex and uniform states. A high diode voltage of 24 mV was obtained with alternative input power of 0.3 µW, corresponding to huge diode sensitivity of 80,000 mV/mW. In the expulsion region, a broad peak in the high frequency region was observed, which is attributed to the weak excitation of uniform magnetization by thermal noise. The high diode sensitivity is of great importance for device applications such as telecommunications, radar detectors, and high-speed magnetic-field sensors.

  9. Effects of climate change on terrestrial animals [Chapter 9

    Science.gov (United States)

    Megan M. Friggens; Mary I. Williams; Karen E. Bagne; Tosha T. Wixom; Samuel A. Cushman

    2018-01-01

    The Intermountain Adaptation Partnership (IAP) region encompasses a high diversity of grassland, shrubland, and forest habitats across a broad range of elevational gradients, supporting high biodiversity in the interior western United States. Terrestrial species comprise a wide range of life forms, each expressing varying levels of habitat specialization and life...

  10. Halogens in chondritic meteorites and terrestrial accretion

    Science.gov (United States)

    Clay, Patricia L.; Burgess, Ray; Busemann, Henner; Ruzié-Hamilton, Lorraine; Joachim, Bastian; Day, James M. D.; Ballentine, Christopher J.

    2017-11-01

    Volatile element delivery and retention played a fundamental part in Earth’s formation and subsequent chemical differentiation. The heavy halogens—chlorine (Cl), bromine (Br) and iodine (I)—are key tracers of accretionary processes owing to their high volatility and incompatibility, but have low abundances in most geological and planetary materials. However, noble gas proxy isotopes produced during neutron irradiation provide a high-sensitivity tool for the determination of heavy halogen abundances. Using such isotopes, here we show that Cl, Br and I abundances in carbonaceous, enstatite, Rumuruti and primitive ordinary chondrites are about 6 times, 9 times and 15-37 times lower, respectively, than previously reported and usually accepted estimates. This is independent of the oxidation state or petrological type of the chondrites. The ratios Br/Cl and I/Cl in all studied chondrites show a limited range, indistinguishable from bulk silicate Earth estimates. Our results demonstrate that the halogen depletion of bulk silicate Earth relative to primitive meteorites is consistent with the depletion of lithophile elements of similar volatility. These results for carbonaceous chondrites reveal that late accretion, constrained to a maximum of 0.5 ± 0.2 per cent of Earth’s silicate mass, cannot solely account for present-day terrestrial halogen inventories. It is estimated that 80-90 per cent of heavy halogens are concentrated in Earth’s surface reservoirs and have not undergone the extreme early loss observed in atmosphere-forming elements. Therefore, in addition to late-stage terrestrial accretion of halogens and mantle degassing, which has removed less than half of Earth’s dissolved mantle gases, the efficient extraction of halogen-rich fluids from the solid Earth during the earliest stages of terrestrial differentiation is also required to explain the presence of these heavy halogens at the surface. The hydropilic nature of halogens, whereby they track

  11. An optimized clarithromycin-free 14-day triple therapy for Helicobacter pylori eradication achieves high cure rates in Uruguay.

    Science.gov (United States)

    Dacoll, Cristina; Sánchez-Delgado, Jordi; Balter, Henia; Pazos, Ximena; Di Pace, María; Sandoya, Gabriela; Cohen, Henry; Calvet, Xavier

    Strong acid inhibition increases cure rates with triple therapy and 14-day are more effective than 7-day treatments. The combination of amoxicillin plus metronidazole at full doses has been shown to overcome metronidazole resistance and to achieve good eradication rates even in patients harboring resistant strains. No previous studies have been reported in Latin-America with this optimized triple-therapy scheme. The aim of the present study was to assess the eradication rate and tolerance of a new first-line treatment regimen associating strong acid inhibition, amoxicillin and metronidazole. Patients from the Clínica de Gastroenterología of the Hospital de Clínicas (Montevideo, Uruguay) were included. Hp status was mainly assessed by at least one of the following: histologyor urea breath test (UBT). A 14-day treatment was prescribed comprising esomeprazole 40mg twice a day plus amoxicillin 1g and metronidazole 500mg, both three times a day. H. pylori cure was assessed by UBT. Forty-one patients were enrolled. Mean age was 53.3±13 years and 17.1% of patients were male. Main indications for treatment were: functional dyspepsia (27.5%), gastritis (45%), gastric or duodenal erosions (20%), gastric ulcer (5%) and intestinal metaplasia (2.5%). H. pylori eradication was achieved in 33 of the 37 patients who returned for follow-up. Eradication rates were 80.5% (95% CI: 68.4-92.6) by intention-to-treat (ITT) analysis and 89.2% (95% CI; 79.2-99.2) per protocol (PP). No major side effects were reported; 26 patients (65.8%) complained of mild side effects (nausea, diarrhea and headache). Cure rates of this triple therapy including esomeprazole, amoxicillin and metronidazole were 81% per ITT and the treatment was well tolerated. These optimal results with a simple clarithromycin-free triple therapy are better than described for standard triple therapy but there is still room for improvement to reach the desired target of 90% per ITT. Copyright © 2017 Elsevier España, S

  12. Spatial vision in Bombus terrestris

    Directory of Open Access Journals (Sweden)

    Aravin eChakravarthi

    2016-02-01

    Full Text Available Bombus terrestris is one of the most commonly used insect models to investigate visually guided behavior and spatial vision in particular. Two fundamental measures of spatial vision are spatial resolution and contrast sensitivity. In this study, we report the threshold of spatial resolution in B. terrestris and characterize the contrast sensitivity function of the bumblebee visual system for a dual choice discrimination task. We trained bumblebees in a Y-maze experimental set-up to associate a vertical sinusoidal grating with a sucrose reward, and a horizontal grating with absence of a reward. Using a logistic psychometric function, we estimated a resolution threshold of 0.21 cycles deg-1 of visual angle. This resolution is in the same range but slightly lower than that found in honeybees (Apis mellifera and A. cerana and another bumblebee species (B. impatiens. We also found that the contrast sensitivity of B. terrestris was 1.57 for the spatial frequency 0.09 cycles deg-1 and 1.26. for 0.18 cycles deg-1.

  13. Negative phototropism in Vaucheria terrestris regulated by calcium, 3: The role of calcium characterized by use of a high-power argon-ion laser as the source of unilateral blue light

    International Nuclear Information System (INIS)

    Kataoka, H.; Watanabe, M.

    1993-01-01

    A tip-growing Xanthophycean algal coenocyte, Vaucheria terrestris sensu Gotz, is able to change the sign of its phototropic response from positive to negative as a result of its ability to sense the fluence rate (= intensity) of unilateral blue light (BL). The mechanism that determines the sign of phototropism was investigated using a high-power argon-ion laser (457.9 nm) as a source of very strong unilateral BL. The fluence-response relationship was determined by changing both the fluence rate and the duration of irradiation. Positive phototropic bending was induced when the fluence rate of BL from the laser was below 60 W m-2. The positive bending obeyed the reciprocity law and was not affected by the concentrations of external Ca2+ ions between 0.4 mM and 4.4 mM. The positive curvature decreased when the alga was exposed to aunilateral pulse of BL with a duration of 10-300 s at fluence rates higher than 60 W m-2. The alga finally showed a deep negative curvature when either the fluence rate or the duration of irradiation was further increased. The inversion of the phototropic response and development of the negative phototropic response was greatly enhanced in the presence of 4.4 mM Ca2+ ions. However, the mechanism that determine the sign of phototropism seemed to require a BL pulse of longer than several seconds, even when the fluence rate was sufficiently high. The role of cytoplasmic Ca2+ ions in positive and negative phototropic responses is discussed

  14. Continuously Growing Ultrathick CrN Coating to Achieve High Load-Bearing Capacity and Good Tribological Property.

    Science.gov (United States)

    Li, Zechao; Wang, Yongxin; Cheng, Xiaoying; Zeng, Zhixiang; Li, Jinlong; Lu, Xia; Wang, Liping; Xue, Qunji

    2018-01-24

    Continuous growth of traditional monolayer CrN coatings up to 24 h is successfully achieved to fabricate ultrathickness of up to 80 μm on the 316 stainless steel substrate using a multiarc ion plating technique. The microstructures, mechanical properties, and tribological properties evolution with the CrN coating continuously growing was evaluated in detail. The transmission electron microscopy observations and inverse Fourier-filtered images reveal a relaxation mechanism during the continuous growth of CrN coating, which can lead to a decrease in the residual stress when coating growth time exceeds 5 h. The scratch test and friction test results both show that the load-bearing capacity of coating is significantly increased as CrN coatings growing thicker. During the scratch test, the ultrathick CrN coating of thickness 80.6 μm is not failed under the load of 180 N, and the dominant failure mechanism is the cohesive failure including wedge spallation and cracking. The dry-sliding friction test results show the mean coefficient of friction and the wear rate of ultrathick CrN are respectively decreased by 17.2 and 56.8% at most compared with the thin coating (thickness is 5.4 μm). The ultrahigh load-bearing capacity and excellent tribological property are attributed to the relaxation mechanism and limited contact pressure as the coating grows continuously.

  15. Achieving transparency in the total system performance assessment of a potential high level radioactive waste repository at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Bailey, J.; Rickertsen, L.; Cotton, T.

    1999-01-01

    This paper has presented an approach to quantitative assessment of the degree of postclosure defense-in-depth provided by the reference system of the VA (Viability Assessment). This approach identifies principal barriers, assesses barriers for common uncertainty and failure mode, conducts barrier neutralization analyses, and evaluates overall defense-in-depth. The neutralization approach of step 3 is particularly useful in untangling the contributions of various barriers to the results calculated by performance assessments. In fact, it provides the only way of assessing the contribution of barriers that are fully redundant with one another. The approach has been applied to the VA reference system. It shows how the natural transport barriers contribute to performance of the system. Since their individual contributions are redundant, uncertainties in those individual contributions are reduced in importance. The analyses also suggest uncertainties common to both of these barriers are important to the safety assessment. Thus, the approach appears to be capable of determining the contribution of the principal barriers to system performance. The ability to use performance assessment to show not only how the repository system is expected to perform, but also how it achieves that performance, should contribute substantially towards providing needed transparency to the safety case for a geologic repository. It is also a valuable tool during the development of the repository design and associated safety case, by identifying areas in which performance would be enhanced by increased redundancy

  16. Relationships between Perceived Parental Involvement in Homework, Student Homework Behaviors, and Academic Achievement: Differences among Elementary, Junior High, and High School Students

    Science.gov (United States)

    Núñez, J. C.; Suárez, N.; Rosário, P.; Vallejo, G.; Valle, A.; Epstein, J. L.

    2015-01-01

    This study aims to produce a deeper understanding of the relationship between perceived parental homework involvement (i.e., parental homework control and parental homework support), student homework behaviors (i.e., time spend on homework completion, time management, and amount of homework completed), and student academic achievement. Using…

  17. A high-stability scanning tunneling microscope achieved by an isolated tiny scanner with low voltage imaging capability

    International Nuclear Information System (INIS)

    Wang, Qi; Wang, Junting; Lu, Qingyou; Hou, Yubin

    2013-01-01

    We present a novel homebuilt scanning tunneling microscope (STM) with high quality atomic resolution. It is equipped with a small but powerful GeckoDrive piezoelectric motor which drives a miniature and detachable scanning part to implement coarse approach. The scanning part is a tiny piezoelectric tube scanner (industry type: PZT-8, whose d 31 coefficient is one of the lowest) housed in a slightly bigger polished sapphire tube, which is riding on and spring clamped against the knife edges of a tungsten slot. The STM so constructed shows low back-lashing and drifting and high repeatability and immunity to external vibrations. These are confirmed by its low imaging voltages, low distortions in the spiral scanned images, and high atomic resolution quality even when the STM is placed on the ground of the fifth floor without any external or internal vibration isolation devices

  18. A high-stability scanning tunneling microscope achieved by an isolated tiny scanner with low voltage imaging capability.

    Science.gov (United States)

    Wang, Qi; Hou, Yubin; Wang, Junting; Lu, Qingyou

    2013-11-01

    We present a novel homebuilt scanning tunneling microscope (STM) with high quality atomic resolution. It is equipped with a small but powerful GeckoDrive piezoelectric motor which drives a miniature and detachable scanning part to implement coarse approach. The scanning part is a tiny piezoelectric tube scanner (industry type: PZT-8, whose d31 coefficient is one of the lowest) housed in a slightly bigger polished sapphire tube, which is riding on and spring clamped against the knife edges of a tungsten slot. The STM so constructed shows low back-lashing and drifting and high repeatability and immunity to external vibrations. These are confirmed by its low imaging voltages, low distortions in the spiral scanned images, and high atomic resolution quality even when the STM is placed on the ground of the fifth floor without any external or internal vibration isolation devices.

  19. A high-stability scanning tunneling microscope achieved by an isolated tiny scanner with low voltage imaging capability

    Science.gov (United States)

    Wang, Qi; Hou, Yubin; Wang, Junting; Lu, Qingyou

    2013-11-01

    We present a novel homebuilt scanning tunneling microscope (STM) with high quality atomic resolution. It is equipped with a small but powerful GeckoDrive piezoelectric motor which drives a miniature and detachable scanning part to implement coarse approach. The scanning part is a tiny piezoelectric tube scanner (industry type: PZT-8, whose d31 coefficient is one of the lowest) housed in a slightly bigger polished sapphire tube, which is riding on and spring clamped against the knife edges of a tungsten slot. The STM so constructed shows low back-lashing and drifting and high repeatability and immunity to external vibrations. These are confirmed by its low imaging voltages, low distortions in the spiral scanned images, and high atomic resolution quality even when the STM is placed on the ground of the fifth floor without any external or internal vibration isolation devices.

  20. Friction stir processing: a new grain refinement technique to achieve high strain rate superplasticity in commercial alloys

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, R.S. [Missouri Univ., Rolla, MO (United States). Dept. of Metallurgical Engineering; Mahoney, M.W. [Rockwell International Corp., Thousand Oaks, CA (United States). Science Center

    2001-07-01

    Friction stir processing is a new thermo-mechanical processing technique that leads to a microstructure amenable for high strain rate superplasticity in commercial aluminum alloys. Friction stirring produces a combination of very fine grain size and high grain boundary misorientation angles. Preliminary results on a 7075 Al demonstrate high strain rate superplasticity in the temperature range of 430-510 C. For example, an elongation of >1000% was observed at 490 C and 1 x 10{sup -2} s{sup -1}. This demonstrates a new possibility to economically obtain a superplastic microstructure in commercial aluminum alloys. Based on these results, a three-step manufacturing process to fabricate complex shaped components can be envisaged: cast sheet or hot-pressed powder metallurgy sheet + friction stir processing + superplastic forging or forming. (orig.)