Complex networks created by aggregation

We study aggregation as a mechanism for the creation of complex networks. In this evolution process vertices merge together, which increases the number of highly connected hubs. We study a range of complex network architectures produced by the aggregation. Fat-tailed (in particular, scale-free) distributions of connections are obtained both for networks with a finite number of vertices and growing networks. We observe a strong variation of a network structure with growing density of connections and find the phase transition of the condensation of edges. Finally, we demonstrate the importance of structural correlations in these networks.Comment: 12 pages, 13 figure

Technological Readiness for E-learning among Undergraduate Students at a Private University in Kenya

The domains of learning and teaching are experiencing great changes as higher-education institutions rapidly adopt the concepts and practices of e-learning. Student readiness is crucial in implementation of E-Learning in institutions of higher learning. E-Learning readiness adds the benefit of encouraging learners to take responsibility for their learning and build self-knowledge and self-confidence. This study sought to assess the technological readiness for e-learning among undergraduate students at a private University in Kenya. The study utilized descriptive research design where 157 undergraduate students were stratified sampled to participate in the study. Data was collected using Readiness Assessment Tool for an E-learning Learning Environment Implementation. The study results indicated that 86% (n=113) of the students did not know how to resolve common hardware or software problems. A similar number (64%, n=84) did not have access to reliable internet in campus or cafes while 69% (n=90) did not know how to log in to the internet, navigate web pages and download files using internet browsers. On the other hand, 69% (n=90) did not know how to resolve common errors e.g. ‘page not found’ or ‘connection timed out’ while surfing the internet and 88% (n=115) had not attended any seminars/workshops related to online learning activities. The results from this study point to fact that the University should offer basic training in computers for the undergraduate students in order to enable them use the internet for e-learning. Keywords: Technological readiness, E-learning, Undergraduate students, Computer

The Pressing Need to Raise the Status of the Teaching Profession: The Launch Story of the Teachers of Australia Social Media Campaign

This paper presents the start-up methodology for a project that leverages the opportunities that social media affords to give teachers voice and agency. In response to negative press about teachers in mainstream media, coupled with research that shows that teachers are working hard to meet student academic and wellbeing needs, the researchers employed the assertive technologies of social media and started a campaign to promote the work of pre-service and in-service teachers. The paper presents the theorising behind the start-up methodology for the social media campaign and outlines a response to an identified opportunity. It argues that social media provides new opportunities for professional connectedness, story sharing and collegial support

Leveraging a Community-Based Research Approach to Explore Research Perceptions Among Suburban Poor and Underserved Populations

This qualitative study explored perceptions of research among a rapidly growing underserved population within a suburban community, a setting that has yet to be sufficiently explored using a community-based research (CBR) approach. We recruited community members from community health care agencies in DuPage County, Illinois, and 79 participants were enrolled in the study. Community researchers conducted nine focus groups comprised of agency clients and eight stakeholder interviews to collect community perspectives regarding the meaning of research and its community impact, current and desired channels of research information, and research motives, discrimination, and funding. Findings revealed four major themes: community members 1) often associate research with medical research or community engagement; 2) rely most heavily on the internet for research information; 3) perceive financial barriers, rather than racial or ethnic barriers, as a significant obstacle to receiving the benefits of research; and 4) trust research conducted by academic institutions

Frequency of occurrence of numbers in the World Wide Web

The distribution of numbers in human documents is determined by a variety of diverse natural and human factors, whose relative significance can be evaluated by studying the numbers' frequency of occurrence. Although it has been studied since the 1880's, this subject remains poorly understood. Here, we obtain the detailed statistics of numbers in the World Wide Web, finding that their distribution is a heavy-tailed dependence which splits in a set of power-law ones. In particular, we find that the frequency of numbers associated to western calendar years shows an uneven behavior: 2004 represents a `singular critical' point, appearing with a strikingly high frequency; as we move away from it, the decreasing frequency allows us to compare the amounts of existing information on the past and on the future. Moreover, while powers of ten occur extremely often, allowing us to obtain statistics up to the huge 10^127, `non-round' numbers occur in a much more limited range, the variations of their frequencies being dramatically different from standard statistical fluctuations. These findings provide a view of the array of numbers used by humans as a highly non-equilibrium and inhomogeneous system, and shed a new light on an issue that, once fully investigated, could lead to a better understanding of many sociological and psychological phenomena.Comment: 5 pages, 4 figure

Evidence and patterns of tuna spawning inside a large no-take marine protected area

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Hernandez, C. M., Witting, J., Willis, C., Thorrold, S. R., Llopiz, J. K., & Rotjan, R. D. Evidence and patterns of tuna spawning inside a large no-take marine protected area. Scientific Reports, 9(1), (2019): 10772, doi:10.1038/s41598-019-47161-0.The Phoenix Islands Protected Area (PIPA), one of the world’s largest marine protected areas, represents 11% of the exclusive economic zone of the Republic of Kiribati, which earns much of its GDP by selling tuna fishing licenses to foreign nations. We have determined that PIPA is a spawning area for skipjack (Katsuwonus pelamis), bigeye (Thunnus obesus), and yellowfin (Thunnus albacares) tunas. Our approach included sampling larvae on cruises in 2015–2017 and using a biological-physical model to estimate spawning locations for collected larvae. Temperature and chlorophyll conditions varied markedly due to observed ENSO states: El Niño (2015) and neutral (2016–2017). However, larval tuna distributions were similar amongst years. Generally, skipjack larvae were patchy and more abundant near PIPA’s northeast corner, while Thunnus larvae exhibited lower and more even abundances. Genetic barcoding confirmed the presence of bigeye (Thunnus obesus) and yellowfin (Thunnus albacares) tuna larvae. Model simulations indicated that most of the larvae collected inside PIPA in 2015 were spawned inside, while stronger currents in 2016 moved more larvae across PIPA’s boundaries. Larval distributions and relative spawning output simulations indicated that both focal taxa spawned inside PIPA in all 3 study years, demonstrating that PIPA is protecting viable tuna spawning habitat.Funding and support was provided by the PIPA Trust, Waitt and Oceans5 Foundations, Sea Education Association, the Prince Albert of Monaco Foundation II, New England Aquarium, and Boston University to R.R. and J.W. C.H. was additionally supported by a National Science Foundation Graduate Research Fellowship. J.L. was additionally supported by NOAA through the Cooperative Institute for the North Atlantic Region (CINAR) under Cooperative Agreement NA14OAR4320158 in the form a CINAR Fellow Award, as well as by the WHOI Academic Programs Office. We thank A. Breef-Pilz for onboard sampling assistance, as well as S. Glancy, J. Pringle, E. Martin, J. Fisher, H. Goss, J. Jaskiel, S. Sheehan, and C. Moller for lab assistance. We thank the PIPA Trust and the PIPA Implementation Office for their support, as well as on-ship Kiribati Observers for their support and assistance: Tekeua Auatabu, Iannang Teaioro, Toaea Beiateuea, Taremon Korere, Kareati Waysang, and Moamoa Kabuati. We thank Q. Hanich for reading sections of this paper in advance. This research was conducted under Kiribati and PIPA permits PRP #s 3/17, 1/16, and 2/15 to JW

Preferential survival in models of complex ad hoc networks

There has been a rich interplay in recent years between (i) empirical investigations of real world dynamic networks, (ii) analytical modeling of the microscopic mechanisms that drive the emergence of such networks, and (iii) harnessing of these mechanisms to either manipulate existing networks, or engineer new networks for specific tasks. We continue in this vein, and study the deletion phenomenon in the web by following two different sets of web-sites (each comprising more than 150,000 pages) over a one-year period. Empirical data show that there is a significant deletion component in the underlying web networks, but the deletion process is not uniform. This motivates us to introduce a new mechanism of preferential survival (PS), where nodes are removed according to a degree-dependent deletion kernel. We use the mean-field rate equation approach to study a general dynamic model driven by Preferential Attachment (PA), Double PA (DPA), and a tunable PS, where c nodes (c<1) are deleted per node added to the network, and verify our predictions via large-scale simulations. One of our results shows that, unlike in the case of uniform deletion, the PS kernel when coupled with the standard PA mechanism, can lead to heavy-tailed power law networks even in the presence of extreme turnover in the network. Moreover, a weak DPA mechanism, coupled with PS, can help make the network even more heavy-tailed, especially in the limit when deletion and insertion rates are almost equal, and the overall network growth is minimal. The dynamics reported in this work can be used to design and engineer stable ad hoc networks and explain the stability of the power law exponents observed in real-world networks.Comment: 9 pages, 6 figure