Information searching behaviors among Vietnamese students during first wave of the COVID-19 pandemic

This study aims to describe the COVID-19 related information searching behaviors and the relationship between those behaviors and the satisfaction with the COVID-19 related information searched on the Internet among university students during first wave of the COVID-19 pandemic in Vietnam

Can hippocampal neurites and growth cones climb over obstacles?

Guidance molecules, such as Sema3A or Netrin-1, can induce growth cone (GC) repulsion or attraction in the presence of a flat surface, but very little is known of the action of guidance molecules in the presence of obstacles. Therefore we combined chemical and mechanical cues by applying a steady Netrin-1 stream to the GCs of dissociated hippocampal neurons plated on polydimethylsiloxane (PDMS) surfaces patterned with lines 2 \ub5m wide, with 4 \ub5m period and with a height varying from 100 to 600 nm. GC turning experiments performed 24 hours after plating showed that filopodia crawl over these lines within minutes. These filopodia do not show staining for the adhesion marker Paxillin. GCs and neurites crawl over lines 100 nm high, but less frequently and on a longer time scale over lines higher than 300 nm; neurites never crawl over lines 600 nm high. When neurons are grown for 3 days over patterned surfaces, also neurites can cross lines 300 nm and 600 nm high, grow parallel to and on top of these lines and express Paxillin. Axons - selectively stained with SMI 312 - do not differ from dendrites in their ability to cross these lines. Our results show that highly motile structures such as filopodia climb over high obstacle in response to chemical cues, but larger neuronal structures are less prompt and require hours or days to climb similar obstacles

Effect of Electrolyzed Cassava Starch-Gelatin Coating on Biochemical Properties and Ripening of Banana (<i>Musa acuminata</i> L.) Fruits

In this study, cassava starch oxidized by the electrolysis was used as an edible coating to improve the shelf life of banana fruits. The effects of coating in solutions of electrolyzed starch with 1, 2 and 3% (w/v) gelatin and without gelatin addition on respiratory rate and biochemical properties of banana during 8 days of storage at room temperature (75-80% relative humidity) were evaluated. The micrographs of scanning electron microscopy showed very thin coating layers (w/v) of gelatin demonstrated the highest efficiency as it delayed the respiratory peak 4 days more than in the uncoated bananas. This study results suggest that electrolyzed starch-gelatin coating could be a potential material to extend the shelf life of fruits

Digital Health Literacy About COVID-19 as a Factor Mediating the Association Between the Importance of Online Information Search and Subjective Well-Being Among University Students in Vietnam

Nguyen LHT, Vo MTH, Tran LTM, et al. Digital Health Literacy About COVID-19 as a Factor Mediating the Association Between the Importance of Online Information Search and Subjective Well-Being Among University Students in Vietnam. Frontiers in Digital Health . 2021;3: 739476.Introduction: Digital health literacy (DHL) has recently been proposed as a means of enabling healthy decisions for protective behavior, preventive measures, and adherence with COVID-19 policies and recommendations especially in the era of the "infodemic". This study aimed to (1) identify COVID-19 related DHL and its association with online information seeking; (2) to elucidate COVID-19 related DHL as a mediator predictor between the importance of online information search and its association with subjective well-being among Vietnamese university students. Methods: A cross-sectional web-based survey was used to elicit the responses of Vietnamese students over 2 consecutive weeks (from April 25 to May 9, 2020, n = 1,003, 70.1% female students, mean age 21.4 ± 3.1). The online survey questionnaire collected data on the sociodemographic characteristics of participants, DHL about COVID-19, information seeking behavior, and subjective well-being. Mediation analysis was conducted using the importance of searching COVID-19 related information as independent variables, subjective well-being as a dependent variable, and DHL as a mediator variable. Results: Among 1,003 students, the mean (SD) of DHL related to COVID-19 was 2.87 ± 0.32. In the survey, 87.2% of the students reported sufficient well-being, while almost 13% reported low or very low well-being. The findings also indicated that search engines were the most popular platform for information seeking by Vietnamese students (95.3%) and 92.8% of participants had searched for information related to the current spread of COVID-19. Not searching for hygiene regulation as part of infection control and an average level of information satisfaction were associated with limited DHL (p < 0.05). The importance of online information searching related to COVID-19 increased the subjective well-being of students significantly and limited DHL (p < 0.05). DHL was found to mediate the relationship between the importance of online information searching and the subjective well-being of students. Conclusion: The finding provides insight into DHL about COVID-19 among university students, and their ability to find, understand, appraise, and use online health related information during lockdown throughout the first COVID-19 pandemic wave. DHL should be highlighted as a mediating factor that enhances the positive effect of the importance of information seeking on psychological well-being. However, further studies are needed to better define the mediating role of DHL across other factors. Copyright © 2021 Nguyen, Vo, Tran, Dadaczynski, Okan, Murray and Van Vo

Design and Realization of Polymeric Waveguide/Microring Structures for Telecommunication Domain

International audiencePolymer-based micro-optical components are very important for applications in optical communication. In this study, we theoretically investigated the coupling of polymeric waveguide and microring structures and experimentally demonstrated an efficient fabrication method to realize these structures on demand. First, the structures were designed and simulated using the FDTD method. The optical mode and loss in the coupling structures were calculated, thereby giving the optimal distance for optical mode coupling between two rib waveguide structures or for optical mode coupling in a microring resonance structure. Simulations results then guided us in the fabrication of the desired ring resonance microstructures using a robust and flexible direct laser writing technique. The entire optical system was thus designed and manufactured on a flat base plate so that it could be easily integrated in optical circuits

Expression of tubulin and axonal neurofilaments after 3 days of culture.

<p>Overlapped DIC and fluorescence images of neurons stained with anti-β-tubulin III antibody (blue) and axonal neurofilament marker SMI 312 (green) for 100 nm (<b>A</b>–<b>B</b>), 300 nm (<b>C</b>–<b>D</b>) and 600 nm (<b>E</b>–<b>F</b>) high lines. Red arrows indicate axons, white ones dendrites. Scale bar, 10 µm.</p

Summary of the GC turning experiments performed on PDMS substrates patterned with 100 nm (n=28), 300 nm (n=25), and 600 nm high lines (n=19) and up to 1h exposure to 300 ng/ml Netrin-1 gradient.

<p>(<b>A</b>) GC and (<b>B</b>) neurites response was classified as attraction (white boxes), repulsion (black boxes) or no crossing (grey boxes). The duration of turning experiments was up to 1 hr.</p