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"Latinas Pathways to STEM: Exploring Contextual Mitigating Factors" presents transnational case studies of Latinas and Mexicanas pursuing a STEM degree/career from the United States (Georgia, New York, Texas) and México. The authors underscore that the experiences of the participants highlighted in this book provide insights into how to support successful Latinas and Mexicanas in STEM career pipelines and pathways. In doing so, the authors address the need for a set of approaches to STEM education policy that acknowledges that institutionalized pipelines often create replication by funding intervention programs that attempt to sterilize context by identifying variables and ignoring the associated contextual mitigating factors (CMFs). Researchers and funders of STEM intervention efforts can learn from the analysis of these case studies that successful Latinas and Mexicanas developed tactical understanding, which reinforced their identity and resisted how they were positioned by negative CMFs, reaffirming their aspirations and successes in STEM. Education graduate students, research methodologists, policy makers, and practitioners will find CMF analysis a useful methodological tool to interrogate how sociocultural factors position designated underrepresented people in STEM pipelines and pathways. Education policies that advocate for the existence and maintenance of pipelines that increase underrepresented Latinas and Mexicanas in STEM are important but are often crafted with blind spots that leave out how context mitigates policy especially at the individual level.

This edited volume extends our field of studies by highlighting novel 21st century curricular designs and pedagogical practices in the preparation of future bilingual teachers and their relevance for advancing curriculum, instruction, and educational achievement across bilingual school contexts. In particular, the volume provides a much-needed overview of innovative bilingual teacher preparation practices designed and implemented to develop bilingual teacher professionals equipped to effect curricular and pedagogical changes in bilingual settings. As such, two main questions guiding the orchestration of the volume are: (a) What innovative curricular and pedagogical designs characterize the field of bilingual teacher education in 21st century? and (b) How do or could these innovative curricular and pedagogical approaches for educating future bilingual teachers influence teacher practices in bilingual contexts for advancing curriculum, pedagogy and the achievement of bilingual learners? [Foreword written by Carmen M. Martínez-Roldán.]

We propose coupling based on contracts as a mechanism to address the problem of exchanging information between parties that require information to work together. Specifically, we show how our approach can be used to couple the deployment of an application with a Grid infrastructure deployment descriptor using ProActive[11,2]. To achieve this, we identify the properties related with information exchange between parties, and we group the properties of interest into typed clauses. We then propose that interfaces can be built using shared typed clauses. If the interfaces between parties are compatible, the coupling of the interfaces can yield a coupling contract. The clauses belonging to the contract represent what information can be shared between the parties, and the type of the clause specifies how this information will be shared. Finally, we show how the deployment of applications on the Grid can benefit from the proposed approach. Unfamiliar applications can couple with deployment descriptors to deploy on alien Grids, without modifying or inspecting neither of them. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether the Jigsawing cooperative-group technique would facilitate second language acquisition (SLA) among third- and fourth-grade migrant Hispanic students in Kansas. A mixed-methods research with triangulation was conducted with 15 students in the Newcomer Program at two Kansas schools. Although standardized test results proved insignificant, criterion-referenced test differences (t-test) between experimental and control groups were significant at the 0.05 level (p = 0.03, df = 4). Observations noted purposeful, cooperative behavior among treatment participants. Their responses to open-ended questions correlated with active participation. Triangulation confirmed observations to be consistent with quantitative results. Although the sample size was small, results indicated that Jigsawing is a valuable tool in SLA with Hispanic migrants. The results support further research. [ABSTRACT FROM AUTHOR]

Optic microscopy, X-ray diffraction (XRD), Mössbauer spectroscopy (MS), Electron microprobe analysis (EPMA) and secondary ions mass spectroscopy (SIMS) were used to study Colombian auriferous soils. The auriferous samples, collected from El Diamante mine, located in Guachavez-Nariño (Colombia), were prepared by means of polished thin sections and polished sections for EPMA and SIMS. Petrography analysis was made using an optical microscope with a vision camera, registering the presence, in different percentages, of the following phases: pyrite, quartz, arsenopyrite, sphalerite, chalcopyrite and galena. By XRD analysis, the same phases were detected and their respective cell parameters calculated. By MS, the presence of two types of pyrite was detected and the hyperfine parameters are: δ1 = 0.280 ± 0.01 mm/s and ΔQ1 = 0.642 ± 0.01 mm/s, δ2 = 0.379 ± 0.01 mm/s and ΔQ2 = 0.613 ± 0.01 mm/s. For two of the samples MS detected also the arsenopyrite and chalcopyrite presence. The mean composition of the detected gold regions, established by EPMA, indicated 73% Au and 27% Ag (electrum type). Multiple regions of approximately 200 × 200 µm of area in each mineral sample were analyzed by SIMS registering the presence of "invisible gold" associated mainly with the pyrite and occasionally with the arsenopyrite. [ABSTRACT FROM AUTHOR]

We present a GPU algorithm for the nearest neighbor search, an important database problem. The search is completely performed using the GPU: No further post-processing using the CPU is needed. Our experimental results, using large synthetic and real-world data sets, showed that our GPU algorithm is several times faster than its CPU version. [ABSTRACT FROM AUTHOR]

In this work a study on gold mineral samples is reported, using optical microscopy, X-ray diffraction (XRD) and Mössbauer spectroscopy (MS). The auriferous samples are from the El Diamante mine, located in Guachavez-Narinño (Colombia) and were prepared by means of polished thin sections. The petrography analysis registered the presence, in different percentages that depend on the sample, of pyrite, quartz, arsenopyirite, sphalerite, chalcopyrite and galena. The XRD analysis confirmed these findings through the calculated cell parameters. One typical Rietveld analysis showed the following weight percent of phases: 85.0% quartz, 14.5% pyrite and 0.5% sphalerite. In this sample, MS demonstrated the presence of two types of pyrite whose hyperfine parameters are δ1 = 0.280 ± 0.002 mm/s and δ1 = 0.642 ± 0.002 mm/s, Δ2 = 0.379 ± 0.002 mm/s and Δ2 = 0.613 ± 0.002 mm/s. [ABSTRACT FROM AUTHOR]

In this work we report the magnetic and structural properties obtained by Mössbauer spectrometry, Vibrating Sample Magnetometer and X-ray diffraction of milled powders with initial composition Nd2(Fe100−xNbx)14B with x = 0 and x = 4. The mixtures were ball milled for different times up to 240 h. Structural and microstructural parameters were derived from high statistics X-ray patterns and discussed as a function of milling time. The Mössbauer spectra of the samples were fitted by means of a sextet and an hyperfine field distribution, associated to a pure iron phase (α-Fe) and a disordered iron-based phase, respectively. The α-Fe grain size decreases from 50 nm for 6 h up to 5 nm for 240 h milling time. The Vibrating Sample Magnetometer results allow to conclude that these samples behave as soft ferromagnets. [ABSTRACT FROM AUTHOR]

In this work we report a comparative study of the magnetic and structural properties of Fe50Al50 alloys produced by mechanical alloying using two different planetary ball mills with the same ball mass to powder mass relation. The Fe50Al50 sample milled during 48 h using the Fritsch planetary ball mill pulverisette 5 and balls of 20 mm, presents only a bcc alloy phase with a majority of paramagnetic sites, whereas that sample milled during the same time using the Fritsch planetary ball mill pulverisette 7 with balls of 15 mm, presents a bcc alloy phase with paramagnetic site (doublet) and a majority of ferromagnetic sites which include pure Fe. However for 72 h of milling this sample presents a bcc paramagnetic phase, very similar to that prepared with the first system during 48 h. These results show that the conditions used in the first ball mill equipment make more efficient the milling process. [ABSTRACT FROM AUTHOR]

Web applications are usually built starting from incomplete design documents and proceeding directly to implementation for some specific software platform. The resulting application is usually difficult to change or extend. Although several methodologies have been proposed in the last few years, most of them use a concrete approach that leverages the features of a specific software platform or concrete Web elements. Model-driven development proposals, on the other hand, are difficult to adopt. This paper discusses a successful intermediate approach that allows the designer to work with abstract artifacts that can be readily mapped into any MVC-based (application) framework, independently of which software platform is used. This methodology is simple and easy to learn, even by those who are not platform experts. We present it in terms of a real-life running application for use by local governments in Chile. [ABSTRACT FROM AUTHOR]