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Embryo development is essential for seed yield and post-germination growth. Glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme in oxidative pentose phosphate pathway (OPPP), is widely involved in plant development and stress tolerance by providing nicotinamide adenine dinucleotide phosphate (NADPH). In this study, the double mutant (g6pd5/6), overexpression line (G6PD5/6OE) and complementation line (g6pd5/6 Comp) of cytosolic glucose-6-phosphate dehydrogenases (Cyt-G6PD) were used to investigate Cyt-G6PD roles in embryo development of Arabidopsis. The results showed that the germination rate of g6pd5/6 seeds was delayed in comparison with that of Col-0; moreover, 11.5% of g6pd5/6 seeds did not germinate. The dysfunction of Cyt-G6PD resulted in decreased fresh weight and primary root length of g6pd5/6 seedlings. The height and silique length of g6pd5/6 plants were also decreased. Moreover, the abortion rate of siliques and seeds of g6pd5/6 plants were increased compared with those of Col-0, G6PD5/6OE and g6pd5/6 Comp lines. However, the dysfunction of Cyt-G6PD did not affect pollen activity; but in g6pd5/6 , the embryo development was partially delayed or inhibited. The contents of fatty acids and storage proteins, two main storage materials in Arabidopsis seeds, were decreased in g6pd5/6 seeds. Exogenous application of fatty acids (C18:2; C18:3) alleviated the delayed germination of g6pd5/6 seeds. RT-qPCR results further demonstrated that the early embryo development genes were down-regulated in g6pd5/6. Taken together, Cyt-G6PD plays a pivotal role in plant seed development by regulating the transcriptions of early embryo development genes and the accumulation of storage materials (especially fatty acids). • Cyt-G6PD mutation affects the transcription of genes involved in embryonic development in Arabidopsis. • Cyt-G6PD mutation decreases the contents of fatty acids and storage proteins in g6pd5/6 seeds. • Cyt-G6PD dysfunction reduces seed yield and delays post-embryonic development of Arabidopsis seedlings. [ABSTRACT FROM AUTHOR]

Conducted in two sections of an introductory chemistry course, the current study assesses the impact of a partially flipped course compared to traditional lectures on student academic performance, motivation, and perceptions. Although the partially flipped course had little impact on student final exam performance in the current course, it had an overall positive effect on student grades in a subsequent course with presence of interaction effect favoring students with lower high school GPA. By implication, the partially flipped course structure has the potential to bridge the achievement gap over time. Similarly, flipped instruction had an overall positive effect on end-of-quarter student motivation, and academically weaker students showed relatively higher motivation increases. Treatment students rated the flipped course much more positively regarding instructional clarity, instructor quality, and course quality. Compared to the student reflections received in our previous study, negative comments were much less in scope and severity in the current study, owing to a “gentler” approach for introducing flipped instruction. The gentler approach might allow student to adapt to the format over time. Additionally, greater accountability due to increased assignments of the pre-class work contributed to higher student preparation and improved perceptions. [ABSTRACT FROM AUTHOR]

This study assessed the impact of flipped instruction on students’ out-of-class study time, exam performance, preference, motivation, and perceptions in two sections of a large undergraduate chemistry course. Flipped instruction caused a shift in student workload without appreciably changing the overall study time. The treatment impact on student performance gradually diminished over time, showing a small but statistically significant effect with the final exam. No marked interaction was identified, indicating that flipped instruction benefited students of diverse backgrounds uniformly. Students in the flipped section showed mixed feelings with about one fifth of them displaying polarized attitudes. Open-ended student survey responses revealed non-compliance with pre-class studying as a serious implementation issue: By slowing down the overall pace of the class, it negatively affected students with different study behaviors and characteristics in ways that partly explained the small, diminishing treatment effect and absence of marked interaction. [ABSTRACT FROM AUTHOR]

This study explored a modified version of hybrid instruction, referred to as the flexible hybrid format, in a lower division electrical engineering course offered at a large public university. The objective of the study is to use longitudinal data to investigate the impact of class attendance, out-of-class study time, and motivation on student exam performance. Generalized least squares and fixed effects models were used in the analyses. It was found that class attendance was indispensable; it was associated with exam performance even when all essential course material was made available online and students generally rated the online instruction component to be of higher quality. The benefit of class attendance was then explained by the ICAP hypothesis and spaced learning practice and it was suggested that online education might be more effective in teaching relatively simpler contents. Out-of-class effort significantly predicated performance in previous weeks, but not in the final period. The harmful effect of cramming was cited to explain this phenomenon. Hence, by implication, time management might be an issue in a flexible hybrid environment. Finally, motivation was found to be a robust predicator of performance and its effect was the strongest when the course was at its most challenging stage. Besides, the relationship between motivation and exam performance was likely to be bidirectional, as higher motivation resulted in better performance, which in turn further boosted motivation. Based on current findings, directions for future research were also suggested to verify our claims and improve our implementation. [ABSTRACT FROM AUTHOR]

Abstract: A brief introduction on the development of electrodeposition of diamond-like carbon (DLC) films was given, and our experiments were done, emphasizing on how to deposit hydrogen-free DLC films. Methanol, acetonitrile and N,N-dimethyl formamide (DMF) were chosen as electrolytes, while Si and conductive glass were used as substrates. The sample deposited on Si through methanol was the only one in this comparative research that produced hydrogen-free DLC film as it was indicated by the FTIR spectroscopy. Two explanations, based on reaction mechanism, were proposed to explain this fact. It was believed that the reaction rate and the effect of hydroxyl groups in the molecules of the electrolytes played important roles in the deposition of hydrogen-free DLC films. [Copyright &y& Elsevier]

A solvothermal route has been developed to synthesize K2V3O8 nanorods via the reduction of V2O5 using ethanol as the reducing agent as well as the solvent at 200°C. X-ray diffraction and selected area electron diffraction analysis revealed that the as-synthesized products are of tetragonal structure K2V3O8. Transmission electron spectroscopy image showed that the obtained K2V3O8 comprises rod-like nanocrystallites. The formation mechanism of K2V3O8 was studied. [Copyright &y& Elsevier]

A solvothermal route has been developed to synthesize nanocrystalline Mn2O3 via the reduction of MnO2 using ethanol as the reducing agent as well as the solvent at 130°C. X-ray diffraction and X-ray photoelectron spectroscopy analysis revealed that the as-synthesized products are of tetragonal structure Mn2O3 (γ-Mn2O3). Transmission electron spectroscopy image showed that the obtained γ-Mn2O3 comprises square-shaped nanocrystallites with the sizes of about 50 nm. The formation mechanism of Mn2O3 was studied. [Copyright &y& Elsevier]

SC ( Solidago canadensis L.) was digested with CS (cattle slurry). The process stability, methane production by anaerobic digestion, and the efficiency of organic matter removal were measured. The maximum methane production of 143.7 L/kg volatile solids was obtained at a SC:CS ratio of 1:3 and a substrate concentration of 6% (based on volatile solids); however, the difference between total methane production for SC:CS ratios of 1:1 and 1:3 was not significant ( p > 0.05). Therefore, based on the SC treatment capacity, the optimum SC:CS ratio is 1:1 for this application. For a 6% substrate concentration, the total methane production (129.6 L/kg volatile solids) at a SC:CS ratio of 1:1 was 123.5% higher than that of a control. The pH was fairly constant (6.8–7.6). The removal efficiencies of total solids, volatile solids, cellulose, hemicellulose, and soluble chemical oxygen demand were 37.3, 41.6, 23.6, 34.8, and 38.8%, respectively, and the T 80 was 30.0% shorter than that for maximum methane production. These results indicate that the process stability and methane production efficiency of SC can be improved by CS addition. [ABSTRACT FROM AUTHOR]

The increase of vegetable planting area lead to the large amounts of VPW (vegetable processing wastes). Effects of V% (VPW proportion) and I% (inoculum proportion) on water free anaerobic co-digestion of VPW with CS (cattle slurry) for methane production was investigated. The results showed that the total methane production was increased from 141.2 L/kg VS (volatile solids) to 186.8 L/kg VS with V% increasing from 17% to 35%. When V%, I% and TS% (total solids content) were 35%, 40% and 7.9%, respectively, the maximal methane production of 186.8 L/kg VS was obtained. However, the optimal conditions were 35% of V% and 30% of I%, the methane production was 170.8 L/kg VS, the maximal methane production was only 9.4% higher than that of the optimal conditions, the TS% of the optimal condition was 8.6% and higher than that of the maximal methane production, the reductions of TS% and VS% for this condition were 29.5% and 49.2%, respectively, and the T 80 for this condition was 42.9% shorter than that of the maximal methane production. The results indicate VPW can be co-digested with CS without water addition. [ABSTRACT FROM AUTHOR]

Crystalline zinc oxide powders with various morphologies have been prepared by hydrothermal treatment of zinc acetate in pure water, KOH or ammonia aqueous solution. It was found that the selected solvents play a different role in controlling the morphologies of the obtained powders. The variation of morphology of the obtained ZnO powder with solvents mainly depends on the different zinc species and their environment during the hydrothermal processing. [Copyright &y& Elsevier]