PORE-CONFINED CARRIERS AND BIOMOLECULES IN MESOPOROUS SILICA FOR BIOMIMETIC SEPARATION AND TARGETING

Selectively permeable biological membranes composed of lipophilic barriers inspire the design of biomimetic carrier-mediated membranes for aqueous solute separation. This work imparts selective permeability to lipid-filled pores of silica thin film composite membranes using carrier molecules that reside in the lipophilic self-assemblies. The lipids confined inside the pores of silica are proven to be a more effective barrier than bilayers formed on the porous surface through vesicle fusion, which is critical for quantifying the function of an immobilized carrier. The ability of a lipophilic carrier embedded in the lipid bilayer to reversibly bind the target solute and transport it through the membrane is demonstrated. Through the functionalization of the silica surface with enzymes, enzymatic catalysis and biomimetic separations can be combined on this nanostructured composite platform. The successful development of biomimetic nanocomposite membrane can provide for efficient dilute aqueous solute upgrading or separations using engineered carrier/catalyst/support systems. While the carrier-mediated biomimetic membranes hold great potential, fully understanding of the transport processes in composite synthetic membranes is essential for improve the membrane performance. Electrochemical impedance spectroscopy (EIS) technique is demonstrated to be a useful tool for characterizing the thin film pore accessibility. Furthermore, the effect of lipid bilayer preparation methods on the silica thin film (in the form of pore enveloping, pore filling) on ion transport is explored, as a lipid bilayer with high electrically insulation is essential for detecting activity of proteins or biomimetic carriers in the bilayer. This study provides insights for making better barriers on mesoporous support for carrier-mediated membrane separation process. Porous silica nanoparticles (pSNPs) with pore sizes appropriate for biomolecule loading are potential for encapsulating dsRNA within the pores to achieve effective delivery of dsRNA to insects for RNA interference (RNAi). The mobility of dsRNA in the nanopores of the pSNPs is expected to have a functional effect on delivery of dsRNA to insects. The importance of pores to a mobile dsRNA network is demonstrated by the lack of measurable mobility for both lengths of RNA on nonporous materials. In addition, when the dsRNA could not penetrate the pores, dsRNA mobility is also not measurable at the surface of the particle. Thus, the pores seem to serve as a “sink” in providing a mobile network of dsRNA on the surface of the particle. This work successfully demonstrates the loading of RNA on functionalized pSNPs and identified factors that affects RNA loading and releasing, which provides basis for the delivery of RNA-loaded silica particles in vivo

QUARTZ CRYSTAL MICROBALANCE INVESTIGATION OF CELLULOSOME ACTIVITY FROM CLOSTRIDIUM THERMOCELLUM ON MODEL CELLULOSE FILMS

The cost of deconstructing cellulose into soluble sugars is a key impediment to the commercial production of lignocellulosic biofuels. The use of the quartz crystal microbalance (QCM) to investigate reaction variables critical to enzymatic cellulose hydrolysis is investigated here, extending previous studies of fungal cellulase activity for the first time to whole cell cellulases. Specifically, the activity of the cellulases of Clostridium thermocellum, which are in the form of cellulosomes, was investigated. To clearly differentiate the activity of free cellulosome and cell-bound cellulosome, the distribution of free cellulosome and cell-bound cellulosome in crude cell broth at different growth stages of C. thermocellum (ATCC 27405) was quantified. Throughout growth, greater than 70% of the cellulosome in the crude cell broth was unattached to the cell. The frequency response of the QCM was shown to capture adsorption and hydrolysis of amorphous cellulose films by the whole-cell cellulases. Further, both crude cell broth and free cellulosomes were found to have similar inhibition pattern (within 0 - 10 g/L cellobiose). Thus, kinetic models developed for the cell-free cellulosomes, which allow for more accurate interfacial adsorption analysis by QCM than their cell-attached counterparts, may provide insight into hydrolysis events in both systems

Development of Digital Education in the Age of Digital Transformation: Citing China’s Practice in Smart Education as a Case Study

Digital education has been catalyzing educational transition, transforming the educational views and instructional techniques while also providing opportunities for high-quality educational development. This is a subject that all nations throughout the world are concerned about. The worldwide practice of integrating digital technologies in teaching has yielded positive results. The Global Digital Education Conference, which was held in Beijing, China, in 2023, called for global collaboration on digital education development. This paper sought to illustrate the significance of digital education for educational reform and to investigate ways for digital education development in this context, using China’s smart education practice as evidence

A Contrastive Study on Dynamic Evolution of Users\u27 Relationship Network in Online Health Community based on Stochastic Actor-oriented Model

Online health community can break the limitations of time and space to provide medical and health information for users, meanwhile can promote the formation and evolution of friendships between users. This paper takes the largest diabetes community in China - Sweet Home as the research, and uses the dynamic social network analysis, which is based on stochastic actor-oriented models, to study the impact of individual attributes and network structure on the evolution of users\u27 friendships. It is found that in sub-forums that highly relate to diabetes, basic user attributes such as gender, age, and disease type have significant impacts on the formation of relationships, while in sub-forum of sharing and accompanying, the detailed attributes such as the number of friends, online time, bonus points have a significant impact on the formation of relationships. However, transitive triads have no significant influences on the formation of friends

The Design and Implementation of Mobile Monitoring System of Transmitting Station Based on Android Platform

AbstractIn view of the high speed development of current mobile platform related technology and wireless telecommunication technology, this paper designs and realized a radio and television launching pad mobile monitoring system based on Android platform. The system as expansion of the present scene monitoring system to receive real-time data on transmitters and control their states by wireless network at any time and place, thus further improve the operation efficiency of transmitting station

Psychological Status of High School Students 1 Year After the COVID-19 Emergency

Background: With the control of the epidemic, adolescents\u27 mental outlook might have improved. However, little evidence existed with regard to the psychological status of adolescents in post-COVID-19 era. This present study aimed to explore the psychological status of high school students after the epidemic getting eased. Methods: A web-based cross-sectional survey was used to obtain data from three high schools, including the demographic information, the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 (GAD-7), the Self-Rating Scale of Sleep (SRSS), and self-designed general recent-status questionnaire. Correlation analysis was performed to explore potential associations between the depression symptoms, anxiety symptoms, and sleep status. The PHQ-9 and GAD-7 differences between nowadays data and the data enrolled 12 months before were also compared. Result: A total of 1,108 qualified questionnaires were obtained. The prevalence of depressive and anxious symptoms was 27.5 and 21.3%, respectively, from mild to severe in all students, while 11.8% of these high students got sleep disturbances. Both the rate and the severity of depression, anxiety and sleep problems of female students were higher than male students. Grade three students suffered higher prevalence and severer mental disturbances than the other two grades. There were significant correlations between the depression symptoms, anxiety symptoms, and sleep status. The psychological status has been improved in nowadays high school students compared with the sample enrolled 12 months before. Conclusion: As a supplement to our former study, this present research provided a perspective on the psychological status of high school students 1 year after the COVID-19 pandemic being well controlled. We should pay attention to the psychological status of high school students, and should also notice the progresses made by this special group after the epidemic