"What It Means to be a Digital Citizen": Using concept mapping and an educational game to explore children's conceptualization of digital citizenship.

Digital citizenship (DC) education is key to a bright future for children in the digital age. Despite its attention in K-12 settings, little is known about how children conceptualize DC, which diminishes the effectiveness of associated lessons. This study introduced the conceptual content cognitive mapping (3CM) approach to investigate children's conceptualization of DC and its changes after digital game-based learning with MinecraftEDU. Results showed that children tended to conceptualize DC superficially as personal responsibility and generally ignored the role of active online engagement. The game's mechanism had weak influence on how children conceptualized this idea, mainly reflected in the change of importance they perceived during the game. These changes were related to their perceptions of emotion, game design, and value commitments. Children jointly showed their interest in the game and exhibited diverse behaviors and learning reflections during the game. Implications for teaching DC and using educational games are discussed to promote DC localization in China.

Unraveling the role of Co3O4 facet for photothermal catalytic oxidation of methanol via operando spectroscopy and theoretical investigation.

Tubular, pie- and bread-shaped forms of Co3O4 with exposed {110}, {112} and {111} facets were prepared and compared in their photothermal catalytic performance and reaction pathways during the oxidation of methanol. Among them, the Co3O4 with exposed {110} facet exhibited the best photothermal catalytic performance (95% methanol conversion, 93% CO2 yield) under solar irradiation, while also maintaining good stability and moisture resistance. Reaction mechanism studies showed that the {110} facets had a strong adsorption capacity for formaldehyde, which facilitated its conversion to formate. The transformation of formaldehyde to formate species was the key step. The key step on the {110} facet was conversion of formaldehyde to a mono-dentate formate species, while conversion on the {112} and {111} facets was mainly to bi-dentate formate species. This study demonstrated that the design of preferential exposed crystal facet can regulate the pathway of photothermal catalytic reaction and realize efficient solar energy utilization.

COVID-19's impacts on the scope, effectiveness, and interaction characteristics of online learning: A social network analysis.

The COVID-19 outbreak brought online learning to the forefront of education. Scholars have conducted many studies on online learning during the pandemic, but only a few have performed quantitative comparative analyses of students' online learning behavior before and after the outbreak. We collected review data from China's massive open online course platform called icourse.163 and performed social network analysis on 15 courses to explore courses' interaction characteristics before, during, and after the COVID-19 pan-demic. Specifically, we focused on the following aspects: (1) variations in the scale of online learning amid COVID-19; (2a) the characteristics of online learning interaction during the pandemic; (2b) the characteristics of online learning interaction after the pandemic; and (3) differences in the interaction characteristics of social science courses and natural science courses. Results revealed that only a small number of courses witnessed an uptick in online interaction, suggesting that the pandemic's role in promoting the scale of courses was not significant. During the pandemic, online learning interaction became more frequent among course network members whose interaction scale increased. After the pandemic, although the scale of interaction declined, online learning interaction became more effective. The scale and level of interaction in Electrodynamics (a natural science course) and Economics (a social science course) both rose during the pan-demic. However, long after the pandemic, the Economics course sustained online interaction whereas interaction in the Electrodynamics course steadily declined. This discrepancy could be due to the unique characteristics of natural science courses and social science courses.

To Be Ethical and Responsible Digital Citizens or Not: A Linguistic Analysis of Cyberbullying on Social Media.

As a worldwide epidemic in the digital age, cyberbullying is a pertinent but understudied concern-especially from the perspective of language. Elucidating the linguistic features of cyberbullying is critical both to preventing it and to cultivating ethical and responsible digital citizens. In this study, a mixed-method approach integrating lexical feature analysis, sentiment polarity analysis, and semantic network analysis was adopted to develop a deeper understanding of cyberbullying language. Five cyberbullying cases on Chinese social media were analyzed to uncover explicit and implicit linguistic features. Results indicated that cyberbullying comments had significantly different linguistic profiles than non-bullying comments and that explicit and implicit bullying were distinct. The content of cases further suggested that cyberbullying language varied in the use of words, types of cyberbullying, and sentiment polarity. These findings offer useful insight for designing automatic cyberbullying detection tools for Chinese social networking platforms. Implications also offer guidance for regulating cyberbullying and fostering ethical and responsible digital citizens.

In-situ atmosphere thermal pyrolysis of spindle-like Ce(OH)CO3 to fabricate Pt/CeO2 catalysts: Enhancing Pt-O-Ce bond intensity and boosting toluene degradation.

In this work, a series of spindle-like CeO2 supports with different contents of surface oxygen vacancies were fabricated by an in-situ atmosphere thermal pyrolysis method. Due to the unique surface physicochemical properties of the modified CeO2 supports, the interaction between Pt and CeO2 can be regulated during the synthesis of the Pt/CeO2 catalyst. The abundant oxygen vacancies on the CeO2 support could preferentially trap Pt2+ ions in solution during the Pt impregnation process and enhance the Pt-CeO2 interaction in the subsequent reduction process, which results in the strongest Pt-O-Ce bonds formed on the PCH catalysts successfully (0.6% Pt loading on the CH support, which generated by thermal pyrolysis of Ce(OH)CO3 under H2 atmosphere). The strong Pt-O-Ce bond would trigger abundant surface oxygen species generated and enhanced the lattice oxygen species transfer from CeO2 supports to Pt nanoparticles. It was crucial to boosting the toluene catalytic activity. Therefore, the PCH catalyst exhibits the highest activity for toluene oxidation (T10 = 120 °C, T50 = 138 °C, and T90 = 150 °C with WHSV = 60,000 mL g-1 h-1) and remarkable durability and water resistance among all catalysts. We also conclude that the Pt-O-Ce bond may be the active site for toluene oxidation by calculating the turnover frequencies (TOFPt-O-Ce) value for all Pt/CeO2 catalysts. Moreover, the DFT calculation indicates that the Pt/CeO2 catalyst with a strong Pt-O-Ce bond possesses the lowest oxygen absorption energy and higher CO tolerance ability, which leads to excellent catalytic performance for toluene and CO catalytic oxidation.

Study of the Influencing Factors of Cyberbullying Among Chinese College Students Incorporated With Digital Citizenship: From the Perspective of Individual Students.

Understanding the influencing factors of cyberbullying is key to effectively curbing cyberbullying. Among the various factors, this study focused on the personal level of individual students and categorized the influencing factors of cyberbullying among college students into five sublevels, i.e., background, Internet use and social network habits, personality, emotion, and literacy related to digital citizenship. Then a questionnaire survey was applied to 947 Chinese college students. The results show that cyberbullying among Chinese college students are generally at a low level. There are many factors influence cyberbullying. Specifically, at the personal background level, gender has a significant impact on cyberbullying and being cyberbullied. In terms of personal Internet use and social network habits, students' average daily online time has no significant correlation with cyberbullying and being cyberbullied; however, the proportion of online non-learning time has a significantly positive correlation with cyberbullying, and the proportion of online learning/work time has a significant impact on being cyberbullied. At the personality level, the Big Five personality traits have varying degrees of correlation with and influence on cyberbullying and being cyberbullied. At the personal emotions level, students' life satisfaction has a significantly negative correlation with cyberbullying and being cyberbullied while it only has a significant impact on being cyberbullied; the personal stress and empathetic concern aspects of empathy have a significantly positive correlation with cyberbullying and being cyberbullied among female students. At the literacy related to digital citizenship level, students' understanding of and compliance with Internet etiquette have significantly negative impacts on cyberbullying; the ability to communicate and collaborate online and Internet addiction have significantly positive impacts on cyberbullying and being cyberbullied; the understanding of and compliance with relevant digital laws and regulations have significantly negative correlations with cyberbullying and being cyberbullied. Overall, college students' digital citizenship level has a significantly negative correlation with cyberbullying but no significant correlation with being cyberbullied. Finally, analysis and suggestions were provided according to these statistical results and the effects of these factors on cyberbullying and being cyberbullied among college students, so as to help solve this problem and provide a new perspective for research in this field.

Enhancement of catalytic toluene combustion over Pt-Co3O4 catalyst through in-situ metal-organic template conversion.

A Pt-Co3O4 catalyst named Pt-Co(OH)2-O was prepared by metal-organic templates (MOTs) conversion and used for catalytic oxidation of toluene. Through the conversion, the morphology of catalysts transformed from rhombic dodecahedron to nanosheet and the coated Pt nanoparticles (NPs) were more exposed. The Binding energy shift in XPS test indicates that the strong metal-support strong interaction (SMSI) has enhanced, and the physicochemical changes caused by it are characterized by other techniques. At the same time, Pt-Co(OH)2-O showed the best catalytic performance (T50 = 157 °C, T90 = 167 °C, Ea = 40.85 kJ mol-1, TOFPt = 2.68 × 10-3 s-1) and good stability. In addition, the in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) studies have shown that because SMSI weakened the Co-O bond, the introduction of Pt NPs can make the migration of oxygen in the catalyst easier. The change of binding energy change and the content of various species in the quasi in situ XPS experiment further confirmed that the Pt-Co(OH)2-O catalyst has stronger SMSI, resulting in its stronger electron transfer ability and oxygen migration ability, which is conducive to catalytic reactions. This work provides new ideas for the development of supported catalysts and provides a theoretical reference for the relevant verification of SMSI.

Macroscopic Hexagonal Co3O4 Tubes Derived from Controllable Two-Dimensional Metal-Organic Layer Single Crystals: Formation Mechanism and Catalytic Activity.

Macroscopic Co3O4 hexagonal tubes were successfully synthesized using hollow two-dimensional (2D) MOL (metal-organic layer) single crystals as sacrificial templates. The hollow 2D MOL single crystals were prepared under hydrothermal conditions with acetonitrile (MeCN) as an interference agent. The formation of hollow-structured 2D MOL single crystals was tracked by time-dependent experiments, and two simultaneous paths-namely, the crystal-to-crystal transformation in solution and the dissolution + migration (toward the external surface) of inner crystallites-were identified as playing a key role in the formation of the unique hollow structure. The calculated change in Gibbs free energy (ΔG = -1.18 eV) indicated that the crystal-to-crystal transformation was spontaneous at 393 K. Further addition of MeCN as an interference agent eventually leads to the formation of macroscopic hexagonal tubes. Among all of the as-synthesized Co3O4, Co-MeCN-O with a hexagonal tube morphology exhibited the best catalytic performance in toluene oxidation, it achieved a toluene conversion of 90% (T90) at ∼227 °C (a space velocity of 60 000 mL g-1 h-1) and the activity energy (Ea) is 69.5 kJ mol-1. A series of characterizations were performed to investigate the structure-activity correlation. It was found that there are more structure defects, more adsorbed surface oxygen species, more surface Co3+ species, and higher reducibility at low temperatures on the Co-MeCN-O than on other Co3O4 samples; these factors are responsible for its excellent catalytic performance. The in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) characterization showed that, when there is no oxygen in the atmosphere, the lattice oxygen may be involved in the activation of toluene, and the gas-phase oxygen replenished by the oxygen vacancies was essential for the total oxidation of toluene on the surface of the Co-MeCN-O catalysts, it also proves the importance of oxygen vacancies. Moreover, for the Co-MeCN-O catalysts, no obvious decrease in catalytic performance was observed after 120 h at 220 °C and it is still stable after cycling tests, which indicates that it exhibits excellent stability for toluene oxidation. This study sheds lights on the controllable synthesis of macroporous-microporous materials in single-crystalline form without an external template, and, thus, it may serve as a reference for future design and synthesis of hollow porous materials with outstanding catalytic performance.

Toluene oxidation over Co3+-rich spinel Co3O4: Evaluation of chemical and by-product species identified by in situ DRIFTS combined with PTR-TOF-MS.

Series of Co3+-rich spinel Co3O4 catalysts were synthesized and evaluated by toluene catalytic oxidation. An outstanding activity was achieved over Co3O4-N utilizing Co(NO3)2·6H2O as precursor (T50 = 211 °C, T90 = 217 °C at conditions: 1000 ppm(v), WHSV = 60 000 mL g-1 h-1). Results of comparative characterizations demonstrated that such excellent performance was mainly attributed to large surface area, high reducibility at low temperature, high abundance of Co3+ ions and structure defects, as well as highly active surface oxygen. The results of in situ DRIFTS revealed that in the air or N2 atmosphere, the by-products were almost the same. The reaction pathway of toluene oxidation can be described as follow: transformation of toluene from benzyl alcohol, benzaldehyde, benzoate, benzene, phenol, benzoquinone, maleic acid and to final products, which were fully confirmed by PTR-TOF-MS. Besides, ring opened by-products, such as acetone, acetic acid, acetaldehyde, etc. were also detected. In this work, the combination of in situ DRIFTS and PTR-TOF-MS provided a promising approach for further understanding of the mechanism of VOCs elimination.

Low-cost photoionization sensors as detectors in GC × GC systems designed for ambient VOC measurements.

Conventional volatile organic compound (VOC) monitoring based on thermal desorption - gas chromatography-mass spectrometry (TD-GC-MS) or gas chromatography-flame ionization detector (TD-GC-FID) is relatively cumbersome and expensive. In this study commercial off the shelf low-cost and low-power photo-ionization detector (PID) sensors are used as simple detectors in VOC analysis systems based on GC, including a miniaturised GC × GC device with portable, low-cost, and low-energy-consumption features. PID sensors produce a voltage signal positively proportional to VOC concentration, which when incorporated into a TD-GC system gave limit of detection of 0.02 ppbV for isoprene. To test PID performance in real-world applications, PID sensors were deployed as (i) a second alternative detector in a GC-Quadruple Time Of Flight Mass spectrometry (GC-Q-TOF-MS), and (ii) the main detector in a compact two-dimensional gas chromatograph (GC × GC). PID sensors with 10.6 eV and 11.7 eV lamps were used to measure eight toxic chemicals including organic sulfide and organic phosphonates via GC; two species were ionized by a 10.6 eV lamp and four species by the 11.7 eV lamp. Commercially available low-cost PIDs designed for standalone could be straightforwardly and effectively re-used as detectors in compact GC × GC systems, in this work showing excellent VOC sensitivity, fast response and low operational demands compared to comparable field instruments based on GC-FID or MS.

High Expression of CCDC34 Is Associated with Poor Survival in Cervical Cancer Patients.

BACKGROUND The present study explored the expression of coiled-coil domain-containing 34 (CCDC34) in cervical cancer (CC) and its prognostic value. MATERIAL AND METHODS GEPIA and Oncomine cancer databases were mined to predict the CCDC34 differential expression level between a CC group and a normal group. Immunohistochemistry was performed to examine the CCDC34 expression in 67 CC and corresponding adjacent tissues. CD31 and vascular endothelial growth factor (VEGF) were stained to reflect tumor angiogenesis in 67 CC tissues. Kaplan-Meier univariate and Cox multivariate survival analysis were done to evaluate the correlation between CCDC34 expression and prognosis of CC patients. RESULTS Both GEPIA and Oncomine cancer databases mining results revealed that CCDC34 was more highly expressed in the CC group than in the normal group (all P<0.05). Our immunochemical staining data showed that CCDC34 expression was dramatically higher in CC than in adjacent normal tissues (71.6 vs. 20.9%; P<0.001). High expression of CCDC34 was strongly associated with histological grade (P=0.022), lymph node metastasis (P=0.044), and FIGO stage (P=0.002). Furthermore, patients with CCDC34-positive expression had much more MVD than those with CCDC34-negative expression (P<0.001). Kaplan-Meier survival analysis showed that CCDC34-positive expression was associated with worse overall survival (OS) (P=0.004) and disease-free survival (DFS) (P=0.005). Additionally, Cox multivariate analysis revealed that CCDC34 was an independent unfavorable prognostic parameter of DFS and OS (P=0.040 and 0.039, respectively). CONCLUSIONS High expression of CCDC34 is an independent unfavorable prognostic parameter for OS and DFS of CC patients, which was strongly associated with tumor angiogenesis.

Tracking the Progress and Mechanism Study of a Solvothermal in Situ Domino N-Alkylation Reaction of Triethylamine and Ammonia Assisted by Ferrous Sulfate.

Atom economic in situ domino N-alkylation reactions of triethylamine/ammonia with 2-(hydroxymethyl)quinolin-8-ol (HL-OH) assisted by FeSO4·7H2O were realized under mild solvothermal conditions at 120 °C in acetonitrile. The resulting tripodal 2,2',2″-[nitrilotris(methylene)]tris(quinolin-8-ol) (H3L3-N) forms a linear trimer [Fe3(L3-N)2] (1). Electrospray ionization mass spectrometry of the reaction solution provides evidence for the intermediates of three steps, while crystallography and X-ray photoelectron spectroscopy characterize the trimer. Shortening the time of the reaction allowed for the organic intermediates to be isolated, which led to a proposed mechanism. The method provides a facile way to produce symmetric tertiary amine from widely used NEt3 and NH3. The results represent an example of the in situ Fe2+-catalyzed domino reaction in which Fe2+ is coordinated by the generated ligands and is involved in each step until the final cluster 1.