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Using consumer socialization theory, this study examined the associations between perceived influence of parents, peers, employment, and media and spending behaviors of emerging adult college students from three different regions of the US: Northeast, South Atlantic, and Mountain regions. Data from the Emerging Adult Financial Capability Study (N = 2,322) were analyzed using structural equation modeling. Greater parental and employment influences perceived by the students were linked with more responsible spending behaviors, while greater peer and media influences were associated with less responsible spending behaviors. This study highlights the importance of the home and the workplace as the nexus for financial learning. This knowledge can help focus efforts to help future emerging adult college students learn responsible spending behaviors.

Noncanonical redox cofactors are attractive low-cost alternatives to nicotinamide adenine dinucleotide (phosphate) (NAD(P)+) in biotransformation. However, engineering enzymes to utilize them is challenging. Here, we present a high-throughput directed evolution platform which couples cell growth to the in vivo cycling of a noncanonical cofactor, nicotinamide mononucleotide (NMN+). We achieve this by engineering the life-essential glutathione reductase in Escherichia coli to exclusively rely on the reduced NMN+ (NMNH). Using this system, we develop a phosphite dehydrogenase (PTDH) to cycle NMN+ with ~147-fold improved catalytic efficiency, which translates to an industrially viable total turnover number of ~45,000 in cell-free biotransformation without requiring high cofactor concentrations. Moreover, the PTDH variants also exhibit improved activity with another structurally deviant noncanonical cofactor, 1-benzylnicotinamide (BNA+), showcasing their broad applications. Structural modeling prediction reveals a general design principle where the mutations and the smaller, noncanonical cofactors together mimic the steric interactions of the larger, natural cofactors NAD(P)+.

Despite increased interest in integrating programming education into K-12 programs, there is a lack of studies on teaching debugging to younger age groups. Therefore, this study proposes practical design components for designing unplugged debugging tasks that affect young learners' debugging performance, problem-solving, and self-efficacy, intending to lower dependence upon tablet-based programming applications. This study incorporated different types of embodiment and language use for designing the unplugged debugging activities. Results indicated that the surrogate embodiment using an everyday language format during the unplugged debugging sessions benefited elementary students' problem-solving and self-efficacy. The discussion includes practical implications for classroom application in elementary classrooms as well as recommendations for future research.

Using robotics and programming, this study investigated the effects of different levels of embodied instruction on the problem-solving, debugging, programming proficiency, self-determination, and self-efficacy of students in ethnically diverse elementary classrooms. The first small-scale, quasi-experimental study involved 37 second-graders, who were randomly assigned to an embody or a non-embody group. Results showed that embodied planning activities benefited these young learners' LEGO Robotics problem-solving and self-determination skills. Based on these findings, a second study implemented different types of embodied activities (full-embody, low-embody, and control condition) in a debugging problem-solving activity for 51 kindergarten and 1st-grade students, also from ethnically diverse populations. The findings from this study suggested that the embodied learning activities promoted students' problem-solving skills in robotics and the use of debugging strategies in coding applications. However, different effects were found for groups by condition and the outcome variable. Based on these mixed results, the authors propose activities applicable in real-world elementary classrooms to introduce practical robotics and programming activities.

BackgroundNoncanonical redox cofactors are emerging as important tools in cell-free biosynthesis to increase the economic viability, to enable exquisite control, and to expand the range of chemistries accessible. However, these noncanonical redox cofactors need to be biologically synthesized to achieve full integration with renewable biomanufacturing processes.ResultsIn this work, we engineered Escherichia coli cells to biosynthesize the noncanonical cofactor nicotinamide mononucleotide (NMN+), which has been efficiently used in cell-free biosynthesis. First, we developed a growth-based screening platform to identify effective NMN+ biosynthetic pathways in E. coli. Second, we explored various pathway combinations and host gene disruption to achieve an intracellular level of ~ 1.5 mM NMN+, a 130-fold increase over the cell's basal level, in the best strain, which features a previously uncharacterized nicotinamide phosphoribosyltransferase (NadV) from Ralstonia solanacearum. Last, we revealed mechanisms through which NMN+ accumulation impacts E. coli cell fitness, which sheds light on future work aiming to improve the production of this noncanonical redox cofactor.ConclusionThese results further the understanding of effective production and integration of NMN+ into E. coli. This may enable the implementation of NMN+-directed biocatalysis without the need for exogenous cofactor supply.

It is challenging to biosynthesize industrially important aldehydes, which are readily consumed by the numerous alcohol dehydrogenases (ADHs) in cells. In this work, we demonstrate that a nicotinamide mononucleotide (NMN+)-dependent redox cofactor cycling system enables aldehyde accumulation in Escherichia coli crude lysates and whole cells. By specifically delivering reducing power to a recombinant enoate reductase, but not to endogenous ADHs, we convert citral to citronellal with minimal byproduct formation (97-100% and 83% product purity in crude lysate- and whole cell-based biotransformation, respectively). We envision the system's universal application to lowering the noise in biomanufacturing by silencing the host's metabolic background.

Biological production of chemicals often requires the use of cellular cofactors, such as nicotinamide adenine dinucleotide phosphate (NADP+). These cofactors are expensive to use in vitro and difficult to control in vivo. We demonstrate the development of a noncanonical redox cofactor system based on nicotinamide mononucleotide (NMN+). The key enzyme in the system is a computationally designed glucose dehydrogenase with a 107-fold cofactor specificity switch toward NMN+ over NADP+ based on apparent enzymatic activity. We demonstrate that this system can be used to support diverse redox chemistries in vitro with high total turnover number (~39,000), to channel reducing power in Escherichia coli whole cells specifically from glucose to a pharmaceutical intermediate, levodione, and to sustain the high metabolic flux required for the central carbon metabolism to support growth. Overall, this work demonstrates efficient use of a noncanonical cofactor in biocatalysis and metabolic pathway design.

The Ehrlich pathway is a major route for the renewable production of higher alcohols. However, the product scope of the Ehrlich pathway is restricted, and the product selectivity is suboptimal. Here, we demonstrate that a Coenzyme A (CoA) detour, which involves conversion of the 2-keto acids into acyl-CoAs, expands the biological toolkit of reaction chemistries available in the Ehrlich pathway to include the gamut of CoA-dependent enzymes. As a proof-of-concept, we demonstrated the first biosynthesis of a tertiary branched-alcohol, pivalcohol, at a level of ∼10 mg/L from glucose in Escherichia coli, using a pivalyl-CoA mutase from Xanthobacter autotrophicus. Furthermore, engineering an enzyme in the CoA detour, the Lactobacillus brevis CoA-acylating aldehyde dehydrogenase, allowed stringent product selectivity. Targeted production of 3-methyl-1-butanol (3-MB) in E. coli mediated by the CoA detour showed a 3-MB:side-product (isobutanol) ratio of >20, an increase over the ratios previously achieved using the conventional Ehrlich pathway.

This study examined what factors might have a positive impact on students' learning outcomes in mathematical understanding and computational thinking skills. Specifically, whether the proposed instructional design combining computational perspectives and an embodied approach in mathematics learning improves (a) mathematics learning, (b) problem-solving skills in programing, and (c) computational thinking. The study used a quantitative quasi-experimental design with 115 second- to fourth-grade students. Findings suggested that embodied activities combined with the practice of taking computational perspectives in solving mathematics problems led to improved knowledge in mathematics, programing concepts, and computational thinking among young learners. This paper also discusses how to make the computational thinking process more concrete and relevant within the context of mathematics to promote computational thinking skills.

BACKGROUND: The ratio of oxygen saturation index (ROX index; or .../.../breathing frequency) has been shown to predict risk of intubation after high-flow nasal cannula (HFNC) support among adults with acute hypoxemic respiratory failure primarily due to pneumonia. However, its predictive value for other subtypes of respiratory failure is unknown. This study investigated whether the ROX index predicts liberation from HFNC or noninvasive ventilation (NIV), intubation with mechanical ventilation, or death in adults admitted for respiratory failure due to an exacerbation of COPD. METHODS: We performed a retrospective study of 260 adults hospitalized with a COPD exacerbation and treated with HFNC and/or NIV (continuous or bi-level). ROX index scores were collected at treatment initiation and predefined time intervals throughout HFNC and/or NIV treatment or until the subject was intubated or died. A ROX index score of ≥ 4.88 was applied to the cohort to determine if the same score would perform similarly in this different cohort. Accuracy of the ROX index was determined by calculating the area under the receiver operator curve. RESULTS: A total of 47 subjects (18%) required invasive mechanical ventilation or died while on HFNC/NIV. The ROX index at treatment initiation, 1 h, and 6 h demonstrated the best prediction accuracy for avoidance of invasive mechanical ventilation or death (area under the receiver operator curve 0.73 [95% CI 0.66-0.80], 0.72 [95% CI 0.65-0.79], and 0.72 [95% CI 0.63-0.82], respectively). The optimal cutoff value for sensitivity (Sn) and specificity (Sp) was a ROX index score > 6.88 (sensitivity 62%, specificity 57%). CONCLUSIONS: The ROX index applied to adults with COPD exacerbations treated with HFNC and/or NIV required higher scores to achieve similar prediction of low risk of treatment failure when compared to subjects with hypoxemic respiratory failure/pneumonia. ROX scores < 4.88 did not accurately predict intubation or death. [ABSTRACT FROM AUTHOR]

Digital-tablets distribute cognition through visual, auditoryand haptic interactivity. We designed a tutor-game thatexplored how narratives ((S)trong/(W)eak) and gestures((I)conic/(D)eictic) could be combined to situate embodiedlearning. Students played seven levels of a fractions gamedesigned to teach them how to create and compare fractions.One hundred thirty-one students (N=131, age x̄ =8.78 yrs,52.6% Female) were randomly assigned to one of four groups(SI, SD, WI, WD) in a 2x2 factorial experiment. Studentscompleted pre/post direct and transfer assessments and tutor-game log data was mined to explore characteristics ofstudents learning. Results revealed a significant interactionbetween narrative and gesture moderated by studentproficiency. In effect, students new to fractions performedbetter in an abstract environment using deictic (pointing)gestures. However, as students' proficiencies improved, theylearned better using iconically enactive gestures in strongnarrative with setting, characters and a plot. This hasimportant implications for designing adaptive learningplatforms and curricula for teaching fractions.

Muscle-derived progenitor cell (myoblast) therapy has promise for the treatment of denervated, weakened, and fibrotic muscle. The best methods for injecting myoblasts to promote fusion and retention have yet to be determined, however. Mesenchymal stem/stromal cells have also been reported to have beneficial effects in restoring damaged tissue, through increasing vascularization and reducing inflammation. The interactions between human primary skeletal myoblasts and bone marrow-derived mesenchymal stem/stromal cells were examined using time-lapse images put into video format. Of interest, there is a high degree of cell-to-cell interaction with microparticles transferring between both cell types, and formation of nanotubules to bridge cytoplasmic contents between the two types of cell. This model provides an in vitro platform for examining mechanisms for cell-to-cell interaction preceding myoblast fusion.

Researchers developed Iteration-1 of a digital tablet tutorgameexploring the impact of narratives (strong (S) vs. weak(W)) and gestural mechanics (conceptual (C) vs. deictic (D))on players’ understanding of mathematical fractions. In atwo-by-two factorial design, 3rd, 4th, and 5th grade elementarystudents at an afterschool program in Harlem, NYC(NTTL=72; x̄AGE=10.31 years [1.64], 67% female) wererandomly assigned to play one of the four tutor-gameenvironments (SC, SD, WC, WD). Pre/post scores on formalfractions assessments showed significant learning for allgroups. Tutor-log data revealed that students usingconceptual gestures were significantly more accurate atestimating and denominating fractions than students usingdeictic gestures. Observational notes, student exit surveys andclinical interviews corroborated that many students used thetutors’ gestures in their explanations of fractions. Thiscollection of data is used to discuss the impact of gesture andnarrative on learning fractions and digital-tutor design.

Students’ beliefs about a subject influence their comprehension and learning of that subject (Ornek et. al., 2008).Many students consider science as a difficult subject to learn. Therefore, this study explored a new way in helping elementarychildren understand abstract science concepts using embodiment, or physically moving their own bodies. Students engagedin activities that helped them learn about abstract science concepts by physically performing tasks related to these scienceconcepts. The purpose of this study was to examine the importance and role of embodiment in students’ understanding andmotivation in elementary science learning. The results provide evidence to suggest that embodiment has remarkable potentialto enhance both children’s understanding and motivation in abstract scientific concepts through the use embodiment.

A science, technology, engineering, and mathematics-influenced classroom requires learning activities that provide hands-on experiences with technological tools to encourage problem-solving skills (Brophy et al. in "J Eng Educ" 97(3):369-387, 2008; Mataric et al. in "AAAI spring symposium on robots and robot venues: resources for AI education," pp 99-102, 2007). The study aimed to bring computational thinking, an applicable skill set in computer science, into existing mathematics and programming education in elementary classrooms. An essential component of computational thinking is the ability to think like a computer scientist when confronted with a problem (Grover and Pea in "Educ Res" 42(1):38-43. doi:10.3102/0013189X12463051, 2013). Computational perspectives (Berland and Wilensky in "J Sci Educ Technol" 24(5):628-647. doi:10.1007/s10956-015-9552-x, 2015) refer to the frame of reference programmers or computer scientists adopt when approaching a problem. The study examined the effects of taking computational perspectives through various degrees of embodied activities (i.e., full vs. low) on students' achievement in mathematics and programming. The study employed a 2 (full vs. low embodiment) × 2 (with vs. without computational perspective taking) factorial condition to evaluate four learning conditions from a combination of embodiment and computational perspective-taking practice. The results from this experimental study (N = 66 kindergarten and first graders) suggest that full-embody activities combined with the practice of computational perspective-taking in solving mathematics problem improved mathematics understanding and programming skills as demonstrated in Scrath Jr. among novice young learners. Moreover, the practice of using a computational perspective significantly improved students' understanding of core programming concepts regardless of the level of embodiment. The article includes recommendations for how to make the computational thinking process more concrete and relevant within the context of a standard curriculum, particularly mathematics.