Merging relative sensing networks: A stability margin perspective

This study considers merging dynamical networks (relative sensing networks in this paper) in terms of a stability margin criterion. The main motivation of this consideration is that merging can cause a significant drop in the stability margin of merged network with respect to the original networks initially with ample stability margins. In this paper, various types of network merging (i.e. undirected/directed homogeneous/heterogeneous dynamical network merging via one-way/two-way links) are analysed to show their effects on the stability margin. In particular, it is shown that (1) merging with one-way links yields the stability margin less than the original networks’; (2) merging undirected homogeneous networks with two-way links results in a stability margin being at least a quantity solely characterized by the positive realness (PRness) of SISO (Single-Input-Single-Output) local dynamics; (3) the quantity depends both on the PRness of SISO local dynamics and the eigenvalues of Laplacian matrix, in case of merging directed homogeneous networks with two-way links; (4) two-way merging using multiple nodes may allow for a large increase in the stability margin; and (5) merging heterogeneous networks may be simply treated as merging homogeneous networks by exploiting the design of link dynamics. Several numerical results are presented to show their consistency with the performed analysis.     

Nonquadratic stabilization conditions for nonhomogeneous Markovian jump fuzzy systems with higher-level operation modes

This paper is concerned with the problem of designing a dissipative control for generalized nonhomogeneous Markovian jump fuzzy systems (MJFSs) that can cover both piecewise-homogeneous MJFSs and nonhomogeneous MJFSs through the use of dual modes, i.e., plant and higher-level modes. Based on a dual-mode-dependent fuzzy control law within a nonparallel distributed compensation (non-PDC) scheme, the nonquadratic stabilization conditions are first formulated in terms of multi-parameterized linear matrix inequalities (M-PLMIs), and then be transformed into a finite set of solvable LMIs without reducing M-PLMIs to PLMIs. Further, since the proposed relaxation technique can address the transition probabilities of plant and higher-level modes at once, the characteristics on mutual dependence between dual modes are fully incorporated into the nonquadratic stabilization conditions. Two illustrative examples are given to show the validity of the proposed approach.     

Motivations of Faculty Self-archiving in Institutional Repositories

Professors contribute to Institutional Repositories (IRs) to make their materials widely accessible in keeping with the benefits of Open Access. However, universities' commitment to IRs depends on building trust with faculty and solving copyright concerns. Digital preservation and copyright management in IRs should be strengthened to increase faculty participation.     

Why Should I Use University Library Website Resources? Discipline Differences

Users across academic disciplines utilize different information sources based on the resource's usefulness and relevance. This study's findings show that users from arts and sciences disciplines are much more likely to utilize university library website resources and printed materials than business users who heavily rely on commercial websites.     

The forgotten promise of e-government maturity: Assessing responsiveness in the digital public sector

Assessing e-government responsiveness is one of the major gaps in the currently dominant e-government maturity models. While we have a relatively large pool of models focusing on technological and organizational integration from a supply side perspective, measures of responsiveness of e-government systems from a user perspective are still lacking. Replicating a study from New Zealand and Australia, this study explores the response time and quality of e-mail response in Danish local and central governments (N = 175). Despite that Denmark is high ranking in international benchmark studies, we find that one third of central government agencies did not respond at all, and close to 80% of the ministries provided none or incomplete answers. Local government responds faster and provides answers that are more complete and accurate than those provided by central government. Implications for e-government are discussed.     

Microfluidic wet spinning of chitosan-alginate microfibers and encapsulation of HepG2 cells in fibers

The successful encapsulation of human hepatocellular carcinoma (HepG2) cells would greatly assist a broad range of applications in tissue engineering. Due to the harsh conditions during standard chitosan fiber fabrication processes, encapsulation of HepG2 cells in chitosan fibers has been challenging. Here, we describe the successful wet-spinning of chitosan-alginate fibers using a coaxial flow microfluidic chip. We determined the optimal mixing conditions for generating chitosan-alginate fibers, including a 1:5 ratio of 2% (w∕w) water-soluble chitosan (WSC) solution to 2% (w∕w) alginate solution. Ratio including higher than 2% (w∕w) WSC solution increased aggregation throughout the mixture. By suspending cells in the WSC-alginate solution, we successfully fabricated HepG2 cell-laden fibers. The encapsulated HepG2 cells in the chitosan-alginate fibers were more viable than cells encapsulated in pure alginate fibers, suggesting that cross-linked chitosan provides a better environment for HepG2 cells than alginate alone. In addition, we found that the adhesion of HepG2 cells on the chitosan-alginate fiber is much better than that on the alginate fibers.     

Bromo-oxidation reaction in enzyme-entrapped alginate hollow microfibers

In this article, the authors present the fabrication of an enzyme-entrapped alginate hollow fiber using a microfluidic device. Further use of enzyme-entrapped alginate hollow fibers as a biocatalytic microchemical reactor for chemical synthesis is also deliberated in this article. To ensure that there is no enzyme leaching from the fiber, fiber surfaces were coated with chitosan. To confine the mobility of reactants and products within the porous hollow fibers the entire fibers were embedded into a transparent polydimethylsiloxane (PDMS) matrix which also works as a support matrix. A vanadium-containing bromoperoxidase enzyme isolated from Corallina confusa was used as a model enzyme to demonstrate the use of these alginate hollow-fiber reactors in bromo-oxidation of phenol red to bromophenol blue at different dye flow rates. Stability of the entrapped enzyme at different temperatures and the effect of the chitosan coating on the reaction conversion were also studied. It was observed that molecules as big as 27 kDa can be retained in the matrix after coating with chitosan while molecules with molecular-weight of around 378 Da can still diffuse in and out of the matrix. The kinetic conversion rate in this microfluidic bioreactor was more than 41-fold faster when compared with the standard test-tube procedure.     

Use and evaluation of information from social media: A longitudinal cohort study

This cohort study examined longitudinal changes in undergraduates' use of social media as information sources in academic and everyday-life contexts, covering types of social media used, purposes of use, and evaluation strategies. Web surveys were used, collecting data from 1,355 and 928 undergraduates in 2013 and 2019. The study found that students used most types of social media less in 2019 than 2013 in both contexts. Only media-sharing services bucked this downward pattern. Overall, a majority of social media types underwent changes in the top three purposes of use. The 2019 cohort used most evaluation strategies more frequently in both contexts. However, they favored simplistic strategies relying on superficial physical cues when evaluating information. Based on the findings, this study provided recommendations for information literacy education and interface design, such as covering multimedia information evaluation, leveraging various heuristics to prime careful use of social media and analytical evaluation of information.     

Epidemiology in Middle School Science Curricula: a COVID-19 Pre–post Intervention

Journal of Science Education and Technology - It is of great importance that science educators teach COVID-19 and related pandemics to boost students’ scientific literacy. A mixed methods...     

“I Managed It Pretty Good”: Birth Narratives of Adolescent Mothers

The aim of this study was to understand adolescent mothers’ childbirth experiences. Semistructured interviews were conducted with participants recruited from a community-based program for adolescent mothers. Fourteen mothers described their birth experiences. Using a narrative analytic approach, responses were reconstructed into birth stories. Stories, condensed into poetic form, were compared and contrasted. Four unique categories emerged: connected births, surreal births, disconnected births, and disempowered births. Categories differed by agency, support, and emotional tone. Positive support was found in stories that portrayed high agency and positive affect, whereas problematic support was apparent in stories that conveyed passivity, frustration, and disappointment. This study has implications for tailoring childbirth education for adolescent mothers and can inform health-care professionals working with this population.