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This study presents first-year findings of a 25-week longitudinal project derived from a two-year longitudinal randomized trial study at the elementary school level in Costa Rica on effective computer-assisted language learning (CALL) approaches in an English as a foreign language (EFL) setting. A pre-test-post-test experimental group design was implemented to evaluate two varying types of CALL curriculum (Treatment A and Treatment B, both technology based to assist English language learning) with a difference in students' time-on-task, as opposed to the Control/Comparison group (that received no treatment and was a typical practice within the regular English teaching time period). Four subtests from Woodcock Munoz Language Survey-Revised (WMLS-R), a norm-referenced, standardized instrument, were selected to monitor participants' oral English development. A total of 76 urban, rural, and urban/marginal schools with 816 third graders were included in the analysis through multilevel modeling. Results suggested that (1) students held very limited oral English proficiency at the beginning of the third grade; (2) although students significantly improved their oral English proficiency during the 25-week intervention, they were still significantly below the typical native English-speaking norm at the end of the third-grade level; (3) those who were exposed to CALL modules in Treatment A developed at a faster rate than did students in Treatment B and in Control classrooms in lexical knowledge and listening skills when statistically controlling for student-level variables, including initial level and time-on-task; (4) although students in CALL intervention (especially in Treatment B) started with a lower level of oral English proficiency, their gain was numerically higher than that in the Control condition; and (5) time-on-task demonstrated to be an irrelevant variable in the study. These findings imply that it is not just exposure to English that matters for significant gains in the language; rather, it is the type of instruction a student receives, or the quality of instruction in which the software engages the students interactively in a hands-on, minds-on, scaffolded manner, that matters the most in developing steep gains. Finally, we recommend that additional research be conducted with groups that move through kindergarten, first grade, and second grade longitudinally to determine cohort effects in learning English via CALL instruction in EFL countries.

This paper presents the findings from a randomized control trial study of reading/literacy-integrated science inquiry intervention after 1 year of implementation and the treatment effect on 5th-grade low-socio-economic African-American and Hispanic students' achievement in science and English reading. A total of 94 treatment students and 194 comparison students from four randomized intermediate schools participated in the current project. The intervention consisted of ongoing professional development and specific instructional science lessons with inquiry-based learning, direct and explicit vocabulary instruction, and integration of reading and writing. Results suggested that (a) there was a significantly positive treatment effect as reflected in students' higher performance in district-wide curriculum-based tests of science and reading and standardized tests of science, reading, and English reading fluency; (b) males and females did not differ significantly from participating in science inquiry instruction; (c) African-American students had lower chance of sufficiently mastering the science concepts and achieving above the state standards when compared with Hispanic students across gender and condition, and (d) below-poverty African-American females are the most vulnerable group in science learning. Our study confirmed that even a modest amount of literacy integration in inquiry-based science instruction can promote students' science and reading achievement. Therefore, we call for more experimental research that focus on the quality of literacy-integrated science instruction from which middle grade students, particularly low-socio-economic status students, can benefit.

This study examined the effect of a quasi-experimental project on fifth grade English learners' achievement in state-mandated standards-based science and English reading assessment. A total of 166 treatment students and 80 comparison students from four randomized intermediate schools participated in the current project. The intervention consisted of on-going professional development and specific instructional science lessons with inquiry-based learning, direct and explicit vocabulary instruction, integration of reading and writing, and enrichment components including integration of technology, take-home science activities, and university scientists mentoring. Results suggested a significant and positive intervention effect in favor of the treatment students as reflected in higher performance in district-wide curriculum-based tests of science and reading and standardized tests of oral reading fluency. (Contains 5 tables.)

Bimetallic nanocatalysts (NCs) composed of two metal elements are a promising way to achieve high catalytic performance based on so-called synergistic effects. In this context, we have designed bimetallic core–shell nanoparticles (NPs) combining a plasmonic metal Ag as a core and a catalytic metal Pt as a shell. Ag@Pt core–shell NPs were synthesized via a seed-mediated growth process allowing fine control of the Ag core size and Pt shell thickness. In the first step, Ag seeds (8–13 nm) with a narrow size distribution (<10%) were synthesized via chemical reduction by tuning the reaction time, heating ramp, and temperature. In the second step, we tuned the Pt shell thickness (from 1 to 6 atomic layers) by adjusting the ratio of the Pt precursor to silver seed concentrations. The Pt shell covered all of the particles, mostly heterogeneously. The robustness and versatility of the synthesis method were tested and successfully applied to different systems (Ag/Au core and Pd/Pt shell). Subsequently, we studied the impact of size and shell thickness on Ag@Pt optical properties by ultraviolet-visible absorption spectroscopy (UV–visible) and by discrete dipole approximation (DDA) calculations. Finally, Ag@Pt core–shell NPs were demonstrated to be more catalytically active than Ag and Pt NPs of similar sizes through a model reaction of reduction of 4-nitrophenol (4-NP) in 4-aminophenol (4-AP) in the presence of NaBH4. These results highlight the synergistic catalytic effect of Ag and Pt species, which may be due to the electronic structure of Ag@Pt core–shell NPs, but may also arise from the localized surface plasmon resonance (LSPR) excitation of the Ag core. This shows the potential of these particles for applications in plasmonic catalysis [ABSTRACT FROM AUTHOR]

The natural pomelo peel fibers powders coating was obtained by spraying method, and this coating was underwater superoleophobic and could be applied in oil/water separation. The pre-wetted sample's separation efficiency was up to 97.0% for light or heavy oils/water mixture only in gravity-driven mass flow. And the pomelo peel powders coatings could still retain more than 98.0% separation efficiency water/soybean oil mixtures after 50 separation cycles. In this article, separation efficiency of natural pomelo peel powders coated mesh was over 97.0% in different pH water/soybean oil mixtures. All these features have shown that the natural and environment-friendly pomelo peel powders coating have enough potential applications in the field of oil/water separation. [ABSTRACT FROM AUTHOR]

The authors report a novel method of fabricating CuO/TiO2 superamphiphobic surface through chemical deposition and sol-gel on Q235 steel. After modification with FAS-17, the water, glycerol, and cooking oil contact angles of CuO/TiO2 coating surpass 150° the corresponding sliding angles are all less 10°. Furthermore, the as-prepared superamphiphobic surfaces can survive 500 times, 400 cm abrasion distance under 2.2 kPa pressure without losing superhydrophobicity. In addition, outstanding corrosion resistance and low adhesion are obtained. The successful fabrication of a robust, good anti-corrosion superamphiphobic surface can be a prospective applied in metal materials. [ABSTRACT FROM AUTHOR]

This study presents first-year findings of a 25-week longitudinal project derived from a two-year longitudinal randomized trial study at the elementary school level in Costa Rica on effective computer-assisted language learning (CALL) approaches in an English as a foreign language (EFL) setting. A pre-test–post-test experimental group design was implemented to evaluate two varying types of CALL curriculum (Treatment A and Treatment B, both technology based to assist English language learning) with a difference in students’ time-on-task, as opposed to the Control/Comparison group (that received no treatment and was a typical practice within the regular English teaching time period). Four subtests from Woodcock Munoz Language Survey-Revised (WMLS-R), a norm-referenced, standardized instrument, were selected to monitor participants’ oral English development. A total of 76 urban, rural, and urban/marginal schools with 816 third graders were included in the analysis through multilevel modeling. Results suggested that (1) students held very limited oral English proficiency at the beginning of the third grade; (2) although students significantly improved their oral English proficiency during the 25-week intervention, they were still significantly below the typical native English-speaking norm at the end of the third-grade level; (3) those who were exposed to CALL modules in Treatment A developed at a faster rate than did students in Treatment B and in Control classrooms in lexical knowledge and listening skills when statistically controlling for student-level variables, including initial level and time-on-task; (4) although students in CALL intervention (especially in Treatment B) started with a lower level of oral English proficiency, their gain was numerically higher than that in the Control condition; and (5) time-on-task demonstrated to be an irrelevant variable in the study. These findings imply that it is not just exposure to English that matters for significant gains in the language; rather, it is the type of instruction a student receives, or the quality of instruction in which the software engages the students interactively in a hands-on, minds-on, scaffolded manner, that matters the most in developing steep gains. Finally, we recommend that additional research be conducted with groups that move through kindergarten, first grade, and second grade longitudinally to determine cohort effects in learning English via CALL instruction in EFL countries. [ABSTRACT FROM PUBLISHER]

This paper presents the findings from a randomized control trial study of reading/literacy-integrated science inquiry intervention after 1 year of implementation and the treatment effect on 5th-grade low-socio-economic African-American and Hispanic students’ achievement in science and English reading. A total of 94 treatment students and 194 comparison students from four randomized intermediate schools participated in the current project. The intervention consisted of ongoing professional development and specific instructional science lessons with inquiry-based learning, direct and explicit vocabulary instruction, and integration of reading and writing. Results suggested that (a) there was a significantly positive treatment effect as reflected in students' higher performance in district-wide curriculum-based tests of science and reading and standardized tests of science, reading, and English reading fluency; (b) males and females did not differ significantly from participating in science inquiry instruction; (c) African-American students had lower chance of sufficiently mastering the science concepts and achieving above the state standards when compared with Hispanic students across gender and condition, and (d) below-poverty African-American females are the most vulnerable group in science learning. Our study confirmed that even a modest amount of literacy integration in inquiry-based science instruction can promote students' science and reading achievement. Therefore, we call for more experimental research that focus on the quality of literacy-integrated science instruction from which middle grade students, particularly low-socio-economic status students, can benefit. [ABSTRACT FROM PUBLISHER]

This study examined the effect of a quasi-experimental project on fifth grade English learners' achievement in state-mandated standards-based science and English reading assessment. A total of 166 treatment students and 80 comparison students from four randomized intermediate schools participated in the current project. The intervention consisted of on-going professional development and specific instructional science lessons with inquiry-based learning, direct and explicit vocabulary instruction, integration of reading and writing, and enrichment components including integration of technology, take-home science activities, and university scientists mentoring. Results suggested a significant and positive intervention effect in favor of the treatment students as reflected in higher performance in district-wide curriculum-based tests of science and reading and standardized tests of oral reading fluency. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 987-1011, 2012 [ABSTRACT FROM AUTHOR]

Abstract Tungsten trioxide (WO 3) and titanium dioxide (TiO 2) decorated commercial stainless steel meshes (SSM 304) were fabricated by chemical deposition and dip coating. WO 3 and TiO 2 particles were firmly and uniformly coated on the membrane surfaces, forming rough micro-nano double structures with underwater superoleophobicity, large contact angles and low oil-adhesion characteristic. Furthermore, the as-prepared membranes achieved effective oil-in-water (O/W) emulsions separation with high efficiency up to 98.5% or more. The separation of O/W emulsions was easily implemented under gravity with water fluxes of >200 L m−2 h−1 or low pressure with water fluxes up to 1300 L m−2 h−1 or more. In addition, the superhydrophilic membranes with WO 3 /TiO 2 coatings were demonstrated for high oil rejection, stable underwater superoleophobic properties after abrasion treatment and steady water permeation flux after several cycles. Highlights • A Method to prepare WO 3 /TiO 2 decorated steel meshes is proposed. • Membranes have a solid structure, good stability and underwater superoleophobicity. • Effectively membrane separation of stabilized oil-in-water emulsions. • Composite membranes have outstanding recyclability and potential for oil/water separation. [ABSTRACT FROM AUTHOR]