447 research outputs found
STEM Heroes: A Narrative-based Intervention to Increase Self-Efficacy and Interest in Science, Technology, Engineering, and Mathematics in Elementary School-aged Children
Over time, researchers have struggled to identify effective interventions to support girls’ self-efficacy and interest in science, technology, engineering, and mathematics (STEM). The primary purpose of this study was to examine whether a theoretically-grounded narrative-based intervention would be able to increase elementary school-aged girls’ self-efficacy in respect to future careers and interest in STEM subjects in school. The study sought to do this by using the stories of the “Heroes of STEM”, a series of four graphic novels developed by the principal researcher, as an intervention tool linking girls’ typically preferred subject (i.e., reading, language arts) to math and science. A quasi-experimental pretest-posttest design was used for the current study. The participants included 4th and 5th grade girls who attended after-care programs in Central New Jersey. The results of the study indicated: (a) that the narrative-based intervention (i.e., the graphic novels) did not affect self-efficacy in STEM careers in the present sample of elementary school-aged girls, (b) that the narrative-based intervention did not affect interest in STEM subjects in school in elementary school-aged girls, and (c) there was not a significant change in girls’ perceptions of who can and cannot be considered members of the scientific community as explored through a pre- and post-intervention drawing task. The non-significant findings of this study impress upon the need to continue to explore effective intervention tools for young girls. They also anecdotally suggest a need for materials similar to the graphic novels that were used in the study as that several of the participants indicated a desire to personally own the stories they were presented with
Dendrimer-Encapsulated Nanoparticles: New Synthetic and Characterization Methods and Catalytic Applications
In this article we describe the synthesis, characterization, and applications of dendrimer-encapsulated nanoparticles (DENs). These materials are synthesized using a template approach in which metal ions are extracted into the interior of dendrimers and then subsequently reduced chemically to yield nearly size-monodisperse particles having diameters in the 1-2 nm range. Monometallic, bimetallic (alloy and core@shell), and semiconductor nanoparticles have been prepared by this route. The dendrimer component of these composites serves not only as a template for preparing the nanoparticle replica, but also as a stabilizer for the nanoparticle. In this perspective, we report on progress in the synthesis, characterization, and applications of these materials since our last review in 2005. Significant advances in the synthesis of core@shell DENs, characterization, and applications to homogeneous and heterogeneous catalysis (including electrocatalysis) are emphasized.U.S. Department of Energy, Office of Basic Energy Sciences DE-FG02-09ER16090U.S. National Science Foundation 0847957Robert A. Welch Foundation F-0032Chemistr
Klipsun Magazine, 1981, Volume 11, Issue 05 - June
https://cedar.wwu.edu/klipsun_magazine/1056/thumbnail.jp
Klipsun Magazine, 1981, Volume 11, Issue 06 - September
https://cedar.wwu.edu/klipsun_magazine/1059/thumbnail.jp
Parallel Evaluation of Multi-join Queries
A number of execution strategies for parallel evaluation of multi-join queries have been proposed in the literature. In this paper we give a comparative performance evaluation of four execution strategies by implementing all of them on the same parallel database system, PRISMA/DB. Experiments have been done up to 80 processors. These strategies, coming from the literature, are named: Sequential Parallel, Synchronous Execution, Segmented Right-Deep, and Full Parallel. Based on the experiments clear guidelines are given when to use which strategy.
This is an extended abstract; the full paper appeared in Proc. ACM SIGMOD'94, Minneapolis, Minnesota, May 24–27, 199
Finite Element Studies of Transient Wave Propagation
The National Bureau of Standards (NBS) has been working to develop a nondestructive test method for heterogenous solids using transient stress waves [1-5]. The method is referred to as the impact-echo method. The technique involves introducing a transient stress pulse into a test object by mechanical impact at a point and measuring the surface displacement caused by the arrival of reflections of the pulse from internal defects and external boundaries. Successful signal interpretation requires an understanding of the nature of transient stress wave propagation in solids containing defects. A primary focus of the NBS program is on using the finite element method to gain this understanding.</p
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Impact echo data from bridge deck testing: Visualization and interpretation
Accurate assessment of the condition of bridges leads to their economic management. Ultrasonic seismic methods can be successfully used for this purpose through evaluation of changes in material characteristics and detection of the development of defects and zones of deterioration. The impact echo (IE) method is of special benefit in evaluation of corrosion-induced deck delamination, due to the method's nondestructive nature, speed of evaluation, and ability to detect delaminated zones at various stages of deterioration: from initial to progressed and developed. The traditional approach in condition assessment of bridge decks by IE on the basis of review of individual test point records and a new automated approach based on three-dimensional (3-D) data visualization are presented. The developed 3-D visualization platform allows both the advanced presentation and interpretation of IE data. The data presentation is provided as 3-D translucent visualizations of reflectors in a bridge deck section and horizontal and vertical cross sections through all distinctive zones, including a zone of delamination. The associated interpretation platform allows both (a) the overall assessment of the condition of the deck, through cumulative distributions and histograms of reflection intensity, and (b) identification of deteriorated zones of the deck for repair or rehabilitation in an efficient and intuitive way. The visualization platform effectively enables an IE device to be used as a type of bridge deck sonar device
Comparación de frecuencias alélicas y genotípicas de los polimorfismos CAPN1-316 Y CAPN1-4751 del gen de la Calpaina en tres poblaciones de ganado criollo boliviano
La terneza de la carne está en parte determinada por el sistema proteico calpaína (CAPN1) / calpastatina (CAST). Bolivia posee en los llanos tres biotipos de ganado Criollo: los Yacumeños, los Chaqueños y los Saavedreños. El objetivo del presente trabajo fue determinar la frecuencia alélica y genotípica del gen de la CAPN1 en tres poblaciones de ganado Criollo de Bolivia. Se obtuvieron muestras de sangre de 28 Criollos del Chaco (CCH), 85 Criollos Yacumeños (CYA) y 30 Criollos Saavedreños (CSV). El ADN se extrajo utilizando el kit comercial Wizard® Genomic Purification, y posteriormente se tipificaron dos polimorfismos (CAPN1-316 y CAPN1-4751) del gen CAPN1 mediante el método ARMS-PCR. La frecuencias alélicas y genotípicas, las heterocigosidades esperadas y observadas, así como, el índice FIS y el desequilibrio de ligamiento (LD) fueron calculadas mediante los programas MS-Tools y Genepop. Las frecuencias de los alelos asociados a mayor terneza para las poblaciones de CCH, CYA y CSV fueron: 23%, 22% y 33 % para el alelo C del SNP CAPN1-316 y 75%, 76% y 60% para el alelo C del CAPN1-4751. La heterocigocidad observada en las tres poblaciones se hallan en un rango de 0,30 a 0,46 para el marcador CAPN1-316 y de 0,21 a 0,60 para el polimorfismo CAPN1-4751. Los resultados demuestran que los bovinos criollos en las poblaciones analizadas poseen altas frecuencias alélicas para las variantes asociadas a mayor terneza de la carne. Por otra parte, no se observaron valores significativos de LD (P>0,01) entre los dos polimorfismos tipificados en las poblaciones estudiadas. Sería necesario tipificar ambos polimorfismos en futuros programas de selección asistida por marcadores genéticos.Meat tenderness is in part determined by the calpain (CAPN1) / calpastatin (CAST) genes. In the lowlands of Bolivia, three well differentiated Creole cattle populations can be distinguished: the Yacumeños, Chaqueños and Saavedreños. The main objective of this research was to determine the allelic and genotypic frequencies of two polymorphisms of the calpain gene in three Creole cattle populations in Bolivia. Blood samples of 28 Creole cattle from Chaqueño cattle (CCH), 85 from Yacumeño cattle (CYA) and 30 from Saavadreño cattle (CSV) were collected. Total DNA was extracted using the commercial kit Wizard® Genomic Purification and subsequently two polymorphisms (CAPN1-316 and CAPN1- 4751) of the CAPN1 gene were genotyped by the amplification refractory mutation system (ARMS-PCR) method. Allelic and genotypic frequencies, expected and observed heterozygosities, the FIS index and the magnitude of linkage disequilibrium (LD) were calculated using the software MS-Tools and Genepop. The allelic frequencies of variants associated with tenderness in the three populations CCH, CYA and CSV were 23%, 22% and 23% for the CAPN1- 316 and 75%, 76% and 60% for the CAPN1-4751. The observed heterozygosities in the three populations fluctuated between 0.30 and 0.46 for the CAPN1-316 marker and between 0.21 and 0.60 for the CAPN1-4751 marker. The results showed that the analysed populations of Creole cattle presented high frequencies of the alleles previously associated with tenderness in meat. The analysis of LD, however, did not show evidence of linkage between the two markers. It is necessary to perform a genetic analysis for both polymorphisms if included in future selection programs.Fil: Pereira, J. A. C.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Falomir Lockhart, Agustin Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Loza, A.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Villegas Castagnasso, Egle Etel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Rojas, P.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Carino, M. . Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Ripoli, María Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Giovambattista, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentin
Design of a conservation program assited by genetic markers in a herd of Yacumeño cattle in Santa Cruz – Bolivia
La Facultad de Ciencias Veterinarias de la UAGRM consolido un programa de conservación del ganado Bovino Criollo Yacumeño a partir del año 2004. La conservación de recursos zoogenéticos generalmente se realiza en poblaciones pequeñas, las cuales tienen un tamaño poblacional efectivo muy reducido. En estos casos es importante realizar apareamientos que mantengan la variabilidad genética alta y los niveles de consanguinidad bajos. El objetivo del presente trabajo consistió en determinar las paternidades y los linajes paternos mediante el uso de marcadores moleculares. El ADN se extrajo partir de muestras de sangre de los 149 animales del hato y se procedió a genotipificar todos los individuos utilizando 18 microsatélites y 7 marcadores del cromosoma Y. Los resultados obtenidos permitieron identificar dos grandes grupos de vacas y 3 linajes paternos. Esta información servirá para diseñar un programa reproductivo que evite en lo posible la perdida de la variabilidad genética y mantenga niveles aceptables de consaguinidad en el hato a conservar.The Faculty of Veterinary Science of the UAGRM consolidated a conservation program of the Yacumeño Creole cattle. The conservation of zoogenetic resources is performed generally in small populations, which usually has a reduced effective population size. In those cases it is important to keep high genetic variability and low levels of consanguinity by performing specific mating among the animals. The main objective of this research consisted in determine the paternity and male lines by using molecular markers. The DNA was extracted from blood sample of 149 animals and were genotyped all the individuals using 18 microsatellites and 7 markers of the Y chromosome. The results obtained allowed to identify two groups of cows and 3 male lines. This information will be useful to design a reproductive program that avoids to a certain degree the lost of genetic variability and will keep acceptable levels of consanguinity among the herd.Fil: Pereira, J. A. C.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Carino, M. H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Hoyos, R.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Rogberg Muñoz, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Loza, A.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Liron, Juan Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Mamani, T.. Universidad Autónoma Gabriel René Moreno; BoliviaFil: Ripoli, María Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Giovambattista, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Genética Veterinaria "Ingeniero Fernando Noel Dulout"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentin
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