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La-related proteins 7 (LARP7) are a class of RNA chaperones that bind the 3' ends of RNA and are constitutively associated with their specific target RNAs. In metazoa, Larp7 binds to the long non-coding 7SK RNA as a core component of the 7SK RNP, a major regulator of eukaryotic transcription. In the ciliate Tetrahymena the LARP7 protein p65 is a component of telomerase, an essential ribonucleoprotein complex that maintains the telomeric DNA at eukaryotic chromosome ends. p65 is important for the ordered assembly of telomerase RNA (TER) with telomerase reverse transcriptase. Unexpectedly, Schizosaccharomyces pombe Pof8 was recently identified as a LARP7 protein and a core component of fission yeast telomerase essential for biogenesis. LARP7 proteins have a conserved N-terminal La motif and RRM1 (La module) and C-terminal RRM2 with specific RNA substrate recognition attributed to RRM2, first structurally characterized in p65 as an atypical RRM named xRRM. Here we present the X-ray crystal structure and NMR studies of S. pombe Pof8 RRM2. Sequence and structure comparison of Pof8 RRM2 to p65 and human Larp7 xRRMs reveals conserved features for RNA binding with the main variability in the length of the non-canonical helix α3. This study shows that Pof8 has conserved xRRM features, providing insight into TER recognition and the defining characteristics of the xRRM.

We elucidate the role of subsurface oxygen on the production of C2 products from CO2 reduction over Cu electrocatalysts using the newly developed grand canonical potential kinetics density functional theory method, which predicts that the rate of C2 production on pure Cu with no O is ∼500 times slower than H2 evolution. In contrast, starting with Cu2O, the rate of C2 production is >5,000 times faster than pure Cu(111) and comparable to H2 production. To validate these predictions experimentally, we combined time-dependent product detection with multiple characterization techniques to show that ethylene production decreases substantially with time and that a sufficiently prolonged reaction time (up to 20 h) leads only to H2 evolution with ethylene production ∼1,000 times slower, in agreement with theory. This result shows that maintaining substantial subsurface oxygen is essential for long-term C2 production with Cu catalysts.

The binary Ta-N chemical system includes several compounds with notable prospects in microelectronics, solar energy harvesting, and catalysis. Among these, metallic TaN and semiconducting Ta3N5 have garnered significant interest, in part due to their synthetic accessibility. However, tantalum sesquinitride (Ta2N3) possesses an intermediate composition and largely unknown physical properties owing to its metastable nature. Herein, Ta2N3 is directly deposited by reactive magnetron sputtering and its optoelectronic properties are characterized. Combining these results with density functional theory provides insights into the critical role of oxygen in both synthesis and electronic structure. While the inclusion of oxygen in the process gas is critical to Ta2N3 formation, the resulting oxygen incorporation in structural vacancies drastically modifies the free electron concentration in the as-grown material, thus leading to a semiconducting character with a 1.9 eV bandgap. Reducing the oxygen impurity concentration via post-synthetic ammonia annealing increases the conductivity by seven orders of magnitude and yields the metallic characteristics of a degenerate semiconductor, consistent with theoretical predictions. Thus, this inverse oxygen doping approach - by which the carrier concentration is reduced by the oxygen impurity - offers a unique opportunity to tailor the optoelectronic properties of Ta2N3 for applications ranging from photochemical energy conversion to advanced photonics.

The binary Ta-N chemical system includes several compounds with notable prospects in microelectronics, solar energy harvesting, and catalysis. Among these, metallic TaN and semiconducting Ta3N5 have garnered significant interest, in part due to their synthetic accessibility. However, tantalum sesquinitride (Ta2N3) possesses an intermediate composition and largely unknown physical properties owing to its metastable nature. Herein, Ta2N3 is directly deposited by reactive magnetron sputtering and its optoelectronic properties are characterized. Combining these results with density functional theory provides insights into the critical role of oxygen in both synthesis and electronic structure. While the inclusion of oxygen in the process gas is critical to Ta2N3 formation, the resulting oxygen incorporation in structural vacancies drastically modifies the free electron concentration in the as-grown material, thus leading to a semiconducting character with a 1.9 eV bandgap. Reducing the oxygen impurity concentration via post-synthetic ammonia annealing increases the conductivity by seven orders of magnitude and yields the metallic characteristics of a degenerate semiconductor, consistent with theoretical predictions. Thus, this inverse oxygen doping approach-by which the carrier concentration is reduced by the oxygen impurity-offers a unique opportunity to tailor the optoelectronic properties of Ta2N3 for applications ranging from photochemical energy conversion to advanced photonics. This journal is

English learners (ELs) are the fastest growing segment of K-12 students. When ELs do not respond to instruction as quickly as their English-speaking peers, teachers may focus on their deficits and wrongly label them as having a learning disability. In this article on the universal design for learning engagement guidelines, we summarize how we have anticipated learning barriers and increased engagement with academic content for ELs in our practice. By teaching strategies for self-regulation and individual coping skills, providing guided practice and support to sustain effort, and giving students various ways to achieve the same goal in a safe learning environment, teachers of ELs and collaborative staff can engage students in their classrooms and schools. We explore universal design for learning for ELs through an assets-based approach and suggest strategies for elementary and secondary teachers to modify for ELs through illustrative case vignettes based on our classroom practice.

Studies have shown that both the departmentalized and self-contained models of instruction can help students achieve strong mathematics scores on standardized tests, and school administrators must consider their teachers and students when deciding on an instructional model. However, little research has considered the effect of the instructional model on initial license teacher candidates and school-university partnerships. Drawing from a Massachusetts college's experience with practicum placements for elementary candidates pursing a generalist license (Grades 1-6), implications for teacher preparation programs are explored as more upper elementary classrooms move to a departmentalized model for mathematics.

Current instruments for assessing university students' statistics anxiety prevailingly emphasize the affective construct component. In order to unfold the construct in a more exhaustive and differentiated manner, a scale for measuring university students' worry, avoidance, and emotionality cognitions was developed. In two samples of education science majors the present pilot study aimed at analyzing the scale's psychometric properties and at gaining preliminary validation results. Principal component analyses led to the formation of a unidimensional scale which appeared to be sufficiently reliable. Its relations to domain-specific self-belief and background variables turned out as theoretically expected -- thus, for the time being the scale should claim criterion validity.

Distance learning is expanding rapidly in universities. While theoretical and qualitative literature stress the critical role of effective interpersonal interactions in motivating students and facilitating learning in online environments, quantitative evidence on the benefits of increased interpersonal interactions on student learning outcomes is limited. This study examines the effect of providing a voluntary in-person meeting time in a physical classroom and increasing instructor email activity in a fully online precalculus course at a public university. We examine student final exam score and course grade as outcome variables. Student selection into courses was minimal since students only had access to one treatment condition at a time. We further used a propensity score matching strategy to address demographic variations in student characteristics across cohorts. Our results indicate that the increased interpersonal interaction opportunities increased final exam scores by 0.22 standard deviations and improved passing rates by 19 percentage points. Rosenbaum's sensitivity analysis indicates that it is unlikely that these results are due to omitted variable bias.

In operando, ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) has been used to evaluate surface states of gadolinia-doped ceria (GDC) thin-film electrodes during H2 oxidation and H2O electrolysis, on yttria-stabilized zirconia (YSZ)-supported solid oxide electrochemical cells (SOCs). Porous nickel (Ni) and gold (Au) overlayers deposited on separate GDC thin films served as current collectors and potential electrocatalysts to facilitate heterogeneous chemistry for H2 oxidation or H2O electrolysis. Electrochemical characterization of the GDC thin-film electrodes complemented in operando XPS measurements of the O 1s spectra to correlate electrochemical overpotentials with surface chemistry near the Ni/GDC and Au/GDC interfaces. Shifts in O 1s binding energies across the metal/GDC/YSZ interfaces signified changes of local surface potential and provided a means of estimating kinetic parameters associated with charge transfer reactions. Effective oxygen partial pressure and surface potential impacted oxide vacancy and ceria polaron concentrations in the GDC, resulting in different reactivities of the GDC under the tested conditions. Both the Ni/GDC and Au/GDC demonstrated much higher currents for H2O electrolysis vs. H2 oxidation for comparable metal/GDC overpotentials due to increased electronic conductivity of the GDC under positive potentials and associated spreading of the electrochemically active region away from the triple-phase boundary. Higher electrochemical activity of the Ni/GDC electrode is attributed to the increased H2 activation on Ni in promoting charge transfer reactions (particularly for H2 oxidation). These results provide a basis for developing more informed reaction mechanisms for both H2 oxidation and H2O electrolysis of GDC-based composite electrodes in SOCs.

In operando, ambient-pressure x-ray photoelectron spectroscopy (AP-XPS) has been used to evaluate surface states of gadolinia-doped ceria (GDC) thin-film electrodes during H2 oxidation and H2O electrolysis, on yttria-stabilized zirconia (YSZ)-supported solid oxide electrochemical cells (SOCs). Porous nickel (Ni) and gold (Au) overlayers deposited on separate GDC thin films served as current collectors and potential electrocatalysts to facilitate heterogeneous chemistry for H2 oxidation or H2O electrolysis. Electrochemical characterization of the GDC thin-film electrodes complemented in operando XPS measurements of the O 1s spectra to correlate electrochemical overpotentials with surface chemistry near the Ni/GDC and Au/GDC interfaces. Shifts in O 1s binding energies across the metal/GDC/YSZ interfaces signified changes of local surface potential and provided a means of estimating kinetic parameters associated with charge transfer reactions. Effective oxygen partial pressure and surface potential impacted oxide vacancy and ceria polaron concentrations in the GDC, resulting in different reactivities of the GDC under the tested conditions. Both the Ni/GDC and Au/GDC demonstrated much higher currents for H2O electrolysis vs. H2 oxidation for comparable metal/GDC overpotentials due to increased electronic conductivity of the GDC under positive potentials and associated spreading of the electrochemically active region away from the triple-phase boundary. Higher electrochemical activity of the Ni/GDC electrode is attributed to the increased H2 activation on Ni in promoting charge transfer reactions (particularly for H2 oxidation). These results provide a basis for developing more informed reaction mechanisms for both H2 oxidation and H2O electrolysis of GDC-based composite electrodes in SOCs.

The activity of polycrystalline thin film photoelectrodes is impacted by local variations of the material properties due to the exposure of different crystal facets and the presence of grain/domain boundaries. Here a multi-modal approach is applied to correlate nanoscale heterogeneities in chemical composition and electronic structure with nanoscale morphology in polycrystalline Mo-BiVO4 . By using scanning transmission X-ray microscopy, the characteristic structure of polycrystalline film is used to disentangle the different X-ray absorption spectra corresponding to grain centers and grain boundaries. Comparing both spectra reveals phase segregation of V2 O5 at grain boundaries of Mo-BiVO4 thin films, which is further supported by X-ray photoelectron spectroscopy and many-body density functional theory calculations. Theoretical calculations also enable to predict the X-ray absorption spectral fingerprint of polarons in Mo-BiVO4 . After photo-electrochemical operation, the degraded Mo-BiVO4 films show similar grain center and grain boundary spectra indicating V2 O5 dissolution in the course of the reaction. Overall, these findings provide valuable insights into the degradation mechanism and the impact of material heterogeneities on the material performance and stability of polycrystalline photoelectrodes.

Cerium oxide (ceria, CeO2) is a technologically important material for energy conversion applications. Its activities strongly depend on redox states and oxygen vacancy concentration. Understanding the functionality of chemical active species and behavior of oxygen vacancy during operation, especially in high-temperature solid-state electrochemical cells, is the key to advance future material design. Herein, the structure evolution of ceria is spatially resolved using bulk-sensitive operando X-ray diffraction and spectroscopy techniques. During water electrolysis, ceria undergoes reduction, and its oxygen non-stoichiometry shows a dependence on the electrochemical current. Cerium local bonding environments vary concurrently to accommodate oxygen vacancy formation, resulting in changes in Ce-O coordination number and Ce3+/Ce4+ redox couple. When reduced enough, a crystallographic phase transition occurs from α to an α' phase with more oxygen vacancies. Nevertheless, the transition behavior is intriguingly different from the one predicted in the standard phase diagram of ceria. This paper demonstrates a feasible means to control oxygen non-stoichiometry in ceria via electrochemical potential. It also sheds light on the mechanism of phase transitions induced by electrochemical potential. For electrochemical systems, effects from a large-scale electrical environment should be taken into consideration, besides effective oxygen partial pressure and temperature.

Two studies were conducted to investigate how self-ratings on questionnaire items reflect the underlying real-scores. Participants gave numerical information about personal attributes (the real-scores), such as age, height, and weight, and subsequently rated themselves regarding these attributes. In Study 1, they rated themselves on a five-point Likert-type scale from three different perspectives, a personal, a general, and an outsiders', inducing three different frames of reference. By regressing these ratings on the real-scores, it was shown that information about means of and differences between the real-scores were not readily reflected by the response scales. The outsiders' perspective resulted in the most adequate representation of the real-score differences, indicated by the intervals between the categories estimated by the ordinal regression models. In Study 2, neutral item wording with a five-point Likert-type scale and a four-point Likert-type scale was used to rule out the effect of positive wording. This increased the adequacy of the representations just slightly. The findings indicate that, even on average, the investigated rating scales and items reflect the numeric real-scores only limitedly and that self-ratings depend on the item phrasing instead of simply representing a coarse measure of the real-scores. All data and analysis scripts are available at https://osf.io/4pcdb/.

Many students around the world are exposed to a rote teaching style in mathematics that emphasizes memorization of procedures. Students are frequently presented with standard types of equations in their textbooks, in which the equal sign is immediately preceding the answer (a + b = c). This exposure can lead to many misconceptions, such as thinking that the equal sign means "do something" or "the answer is." This paper describes students' understanding of the equal sign when solving nonstandard equations in Jordan on the Early Grade Mathematics Assessment (EGMA) and in India on a number sense screener. Common misconceptions are shared, as well as strategies for improving instruction with the equal sign and non-standard equations to prevent future errors.

According to the United Nations Human Development Report (2016), poor, marginalized, and vulnerable groups still face substantial barriers to access post-secondary education and employment. These marginalized and vulnerable groups include women, girls, indigenous peoples, ethnic minorities, people with disabilities, migrants and refugees, the LGBTI community, and those discriminated because of their socio-economic status (UN Human Development Report (2016). Increasingly, proficiency in mathematics is required for careers and for solving daily problems in life (Starkey & Kline, 2008; Ramaa, 2015). Basic numerical, mathematical, and scientific skills are an important mechanism to further education and to enable individuals to improve their job market potential. The risk of underachievement in mathematics around the world is greatest for students from low-income backgrounds, as well as linguistic and ethnic minorities (Ramaa, 2015; National Research Council, 1989). In India, these factors are compounded by lack of early exposure to math, poor teacher quality, and large class sizes (ASER, 2014). Although some research has explored difficulties in arithmetic for economically disadvantaged elementary students in India (see Ramaa, 2015), the challenges that marginalized adolescents encounter in completing secondary mathematics courses has been largely unexamined. In this qualitative exploratory study, conducted from October 2015 to February 2016, we sought to understand the characteristics of adolescents from socio-economically marginalized communities in Mumbai and Bangalore, India, and their determination and perseverance to overcome challenges in mathematics and complete their secondary education. In particular, the study followed students who had dropped out of mainstream school and enrolled in India's National Institute of Open Schooling Program to complete their high school education and attempt the 10th standard board exams. Results from data collected in the academic year showed that there were multiple factors, including lack of learning foundational skills at the primary school level and the type of intervention provided to complete high school, which influenced the students' achievement in mathematics. Findings from the study inform policy and programmatic decisions for students enrolled in India's National Institute of Open Schooling Program.

When teachers conduct a universal screening in mathematics, they identify students who are struggling with mathematical content and adjust their instruction. In this mixed-methods study in Kolkata, India, teachers piloted a screening tool at the beginning of the academic year in 5th grade to determine students' (n = 171) understanding of fractional number sense. The results of the screening show that the majority (70%) of students in fifth grade are in need of more instruction in foundational fraction concepts. Common misconceptions on screener items are shared, as well as strategies for improving fraction instruction to prevent future errors.