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A growing number of studies have shown the benefits of K-12 integrated science and engineering education. With this study, we add to the literature by documenting the relationship between STEM learning and engagement, and the demographic characteristics that impact achievement in STEM. This longitudinal study followed a diverse group of 245 middle school students from sixth grade to eighth grade. Students in two cohorts, cohort I and cohort II, participated in three different integrated STEM units during middle school, one in each grade level. Each curriculum unit focused on the same engineering concepts and practices but addressed different science content standards. The students completed science content tests and engagement surveys before and after the curriculum units. The results of the mixed-effects model analysis showed that behavioral engagement and career inspiration played a critical role in student achievement. While the achievement gap between students of color (SOC) and their White peers was narrowed in cohort II, the achievement gap between the SOC and their White peers in cohort I remained. Our analysis also revealed no gender differences in student achievement. These findings can inform the design of curriculum interventions that specifically target closing the achievement gaps between different groups of students.

This research is motivated by the perspective that when empirical studies and assessment frameworks inform each other, assessments can enrich science education and strengthen its connections to modern science. The research proposes a bioenergy competency assessment for science education. It uses an argument-based approach to validation. Multiple types of validity evidence were collected to support the proposed scores use and scores interpretation. Along with reporting a series of psychometric properties of response data, the findings indicated that empirical response data corresponded to the hypothesized data structure. The latent logistic scale established through a generalized partial credit model (GPCM) seemed useful in measuring students' bioenergy competency.

In this paper, we first systematically sorted out the characteristics of pop singing and musical theater singing and explored the generation of emotion and melody application of pop singing in musical theater singing. Then, the gray GM(1,1) model is analyzed, and a gray data mining model based on data analysis is constructed to predict the application of pop singing in combination with the data mining model under data analysis. Finally, the prediction analysis was conducted to use characterization, timbre and style in pop singing, respectively. The results showed that the score of character building was 90, and the errors between the predicted and actual values of timbre and style were between ±0.1 and ±1, respectively, which were within an acceptable range.

"Active learning" has been used to describe classrooms that have varied widely with respect to instructional topics, age of learners, and the procedures used to operationalize the general notion of the term. In most cases, the specific variant of active learning under investigation has been more effective than the particular control used for comparison. The goal of the current study was to unambiguously describe, implement, and assess 4 different active learning implementations that varied based on the instructional technique employed by the teacher. The specific topic taught was the procedure for constructing experiments in which a single causal factor is clearly identified and there are no confounds. The procedure is commonly known in the literature on early scientific thinking as the "control of variables strategy" (CVS). The sample consisted of 145 3rd- and 4th-grade students from 3 schools. Students in each grade at each school were randomly assigned to 1 of 4 active learning conditions. Learning of CVS was measured through a hands-on, active learning activity and a written pre- and posttest. Results indicated that compared to minimal guidance/minimal guidance/activity, modeling/direct guidance/activity resulted in significantly higher levels of CVS knowledge on the hands-on activity. When examining student learning from pre- to posttest, students in all conditions had significant learning gains. However, the largest effect sizes were for modeling/direct guidance/activity followed by modeling/modeling/activity, and the weakest effect size was for minimal guidance/minimal guidance/activity. Thus, more direct/explicit forms of active learning promoted higher learning of CVS than more inquiry-based forms.

Background: Expanding opportunities to experience engaging STEM educational programs is an important pathway to increasing students' interest and competencies in STEM and, ultimately, motivation to pursue STEM careers. After-school programs offer one means to achieve this aim, but barriers such as a lack of transportation or available teachers may limit participation for some students in this context. Transitioning after-school STEM programs to in-school can provide opportunities to increase reach by removing these and other barriers. However, it is likely that this change in the learning context, from after-school to in-school, impacts student experiences and, ultimately, program efficacy by altering how students and teachers interact; as teachers and students adjust their behaviors and expectations to a more traditional learning context. To examine this potential effect, self-determination theory was used to frame how the learning context influences the social and motivational outcomes of a STEM program for underserved youth. In-school (N = 244; 39% girls, M[subscript age] = 13, 63% Caucasian, 18% African American, 6% Multiracial) and after-school (N = 70, 33% girls, M[subscript age] = 12, 55% Caucasian, 16% Multiracial, 13% Latino/a) program students completed surveys that assessed teacher-student interactions, and student psychological needs and motivation. In a structural equation model, student perceptions of teachers were entered as predictors of motivation for the program directly and mediated by psychological need satisfaction. Learning context (0 = in-school, 1 = after-school) was entered as a ubiquitous predictor. Results: Findings support the theorized model where perceptions of teachers positively predicted psychological need satisfaction (R[superscript 2] = 0.20), and both variables positively predicted more self-determined motivation (R[superscript 2] = 0.30-0.35). Findings also demonstrate an effect of learning context where learning context negatively predicted the less self-determined motivations only (R[superscript 2] = 0.06-0.10) (i.e., in-school contexts are associated with less desirable motivational outcomes). Conclusion: Findings reinforce the instrumental role of students' positive perceptions of teachers in fostering a more desirable self-determined motivation for STEM program participation. Additionally, in-school programs must consider and integrate novel approaches that mitigate the negative impact of established in-school structures and processes (e.g., grades and mandatory participation) on student motivation for these programs and, potentially, interest in STEM careers.

Electrochemical CO2 reduction (ECR) to value-added products is regarded as a sustainable strategy to mitigate global warming and energy crisis, and designing highly efficient and robust catalysts is essential. In this work, transition metal sulfides (TMS)-decorated CuS microflower-like structures were prepared via the one-pot hydrothermal synthesis method for ECR to CO, and the influence of TMS doping on ECR performance was demonstrated. Characterization of the catalysts was performed using XRD, FESEM-EDS, N2 physisorption, and XPS, revealing the successful loading of TMS, the formation of microflower-like architectures and the generation of sulfur vacancies. Electrochemical tests demonstrated that doping ZnS, Bi2S3, CdS and MoS2 improved the intrinsic CO2 reduction activity of the CuS catalyst. Particularly, the MoS2-CuS composite catalyst with imperfect petal-like structure showed uniform distribution of edge Mo sites, which worked synergistically with the formed grain boundaries (GBs) and undercoordinated S vacancy sites in promoting CO2 activation, stabilizing *COOH adsorption, facilitating *CO desorption, and lowering the energy barrier of the potential-limiting step for improved CO selectivity. The MoS2-CuS catalyst achieved a maximum CO selectivity of 83.2% at –0.6 V versus the reversible hydrogen electrode (RHE) and a high CO cathodic energetic efficiency of 100%. At this potential, the catalyst maintained stable catalytic activity and CO selectivity during a 333-min electrolysis process. The findings will offer a promising avenue for the development of efficient and stable catalysts for CO production from ECR. [ABSTRACT FROM AUTHOR]

MicroRNAs play an important role in the interaction between viruses and hosts. In this study, we found that the expression level of miR-33b-5p was markedly increased in human immunodeficiency virus type 1 (HIV-1)–infected cell lines and the serum of person with HIV-1. Further investigation revealed that the level of ATP-binding cassette transporter (ABCA1), which transports cholesterol between intracellular and extracellular compartments to maintain cholesterol homeostasis, was reduced in HIV-1–infected target cells, as the target gene of miR-33b-5p. Furthermore, HIV-1 infection stimulated abnormal lipid transport in macrophages, resulting in lipid accumulation in cells. These changes can be reversed by an miR-33b-5p inhibitor. We discovered a mechanism through which HIV-1 infection caused miR-33b-5p to target ABCA1 and caused aberrant lipid transport, providing a novel method for diagnosing and treating poor lipid metabolism in person with HIV-1. [ABSTRACT FROM AUTHOR]

The Ordovician Wulalike Formation in the northwestern Ordos Basin is a new prospect for exploring marine shale gas in China, facing prominent problems such as unclear reservoir conditions and the distribution of enrichment areas. The types of reservoir space, fracture development, porosity composition, and physical properties of the lower Wulalike Formation are discussed through the multi-method identification and quantitative evaluation of reservoir space for appraisal wells. The Wulalike Formation in the study area contained fractured shale reservoirs with matrix pores (mainly inorganic pores) and permeable fractures. The fracture system of the lower Wulalike Formation is dominated by open bed-parallel fractures that are intermittent or continuous individually, with a width of 0.1–0.2 mm and spacing of 0.5–14.0 cm. The fracture-developed intervals generally exhibit bimodal or multimodal features on NMR T2 spectra and have a dual-track feature with a positive amplitude difference in deep and shallow resistivity logs. The length and fracture porosity of fracture-developed intervals varied greatly in different parts of the study area. In the Majiatan-Gufengzhuang area in the southern part of the study area, the fracture development degree generally decreased from west to east. In the Shanghaimiao area in the central part of the study area, fractures were extremely developed, the continuous thickness of the fracture-developed interval was generally more than 20 m, and the average fracture porosity was higher than 1.3%. In the Tiekesumiao area in the northern part of the study area, the fracture development degree was generally lower than that in the central and southern parts of the study area and also showed a decreasing trend from west to east. The lower Wulalike Formation had a total porosity of 2.46–7.08% (avg. 4.71%), roughly similar to the Longmaxi Formation in the Sichuan Basin, of which matrix porosity accounts for 34.0–90.0% (avg. 61.1%) and fracture porosity accounts for 10.0–66.0% (avg. 38.9%). From this, it could be inferred that the shale gas accumulation type of the lower Wulalike Formation in the northwest margin of the basin is mainly a fractured shale gas reservoir controlled by structure, and its "sweet spot area" is mainly controlled by tectonic setting and preservation conditions. This indicates that the Wulalike Formation in the northwestern Ordos Basin has good shale gas exploration prospects, and a large number of fault anticlines or fault noses formed by reverse dipping faults have the potential of favorable exploration targets. [ABSTRACT FROM AUTHOR]