3,023 research outputs found
Ridge Network in Crumpled Paper
The network formed by ridges in a straightened sheet of crumpled paper is
studied using a laser profilometer. Square sheets of paper were crumpled into
balls, unfolded and their height profile measured. From these profiles the
imposed ridges were extracted as networks. Nodes were defined as intersections
between ridges, and links as the various ridges connecting the nodes. Many
network and spatial properties have been investigated. The tail of the ridge
length distribution was found to follow a power-law whereas the shorter ridges
followed a log-normal distribution. The degree distribution was found to have
an exponentially decaying tail, and the degree correlation was found to be
disassortative. The facets created by the ridges and the Voronoi diagram formed
by the nodes have also been investigated.Comment: 8 pages, 10 figure, 2 tables Replaced due to wrong formating of
author name
Creating an International Learning Community
Thousands of university students travel to the United States every year to engage in higher education, both as undergraduates and as graduate students. This provides a strategically rich opportunity for Christian ministry that has potential for global impact. Part of this potential is to provide ministry leadership training, particularly if students are from countries that allow little freedom for such education. The challenge is to offer culturally appropriate leadership training that is applicable in various cultural contexts and that does not inadvertently cause offense by violating cultural norms of the various students. The desire is to create an educational environment that is culturally accessible to international students, and that trains domestic and international students to be leaders in our globalized world. After considering a number of approaches to address these challenges, it was decided to work with an existing local school of ministry and enable this school to transform into an International Learning Community. This dissertation and accompanying artifact provide necessary research and practical help to make such a transition possible. Section One of the dissertation describes in more detail the potential problems when working in culturally complex settings, as well as pointing out emotional and support needs unique to international students. Section Two describes several approaches considered to address the challenges. Section Three presents research that will provide substantive training content for a school staff and student body. The research focuses on cultural intelligence, cross-cultural hermeneutics, cross-cultural communication, and culture-transcending biblical leadership principles. Section Four explains the outline of x the artifact and briefly describes the courses included in the artifact. Section Five presents parameters of the artifact with brief descriptions of goals, scope, audience, and further course development indicated. Section Six discusses preliminary conclusions regarding the effectiveness of the overall project
The negative acute phase response of serum transthyretin following Streptococcus suis infection in the pig
Peer reviewedPublisher PD
Spatial Distribution of Competing Ions around DNA in Solution
The competition of monovalent and divalent cations for proximity to negatively charged DNA is of biological importance and can provide strong constraints for theoretical treatments of polyelectrolytes. Resonant x-ray scattering experiments have allowed us to monitor the number and distribution of each cation in a mixed ion cloud around DNA. These measurements provide experimental evidence to support a general theoretical prediction: the normalized distribution of each ion around polyelectrolytes remains constant when ions are mixed at different ratios. In addition, the amplitudes of the scattering signals throughout the competition provide a measurement of the surface concentration parameter that predicts the competition behavior of these cations. The data suggest that ion size needs to be taken into account in applying Poisson-Boltzmann treatments to polyelectrolytes such as DNA
Recommended from our members
Impact of Molecular Architecture and Adsorption Density on Adhesion of Mussel-Inspired Surface Primers with Catechol-Cation Synergy.
Marine mussels secrete proteins rich in residues containing catechols and cationic amines that displace hydration layers and adhere to charged surfaces under water via a cooperative binding effect known as catechol-cation synergy. Mussel-inspired adhesives containing paired catechol and cationic functionalities are a promising class of materials for biomedical applications, but few studies address the molecular adhesion mechanism(s) of these materials. To determine whether intramolecular adjacency of these functionalities is necessary for robust adhesion, a suite of siderophore analog surface primers was synthesized with systematic variations in intramolecular spacing between catechol and cationic functionalities. Adhesion measurements conducted with a surface forces apparatus (SFA) allow adhesive failure to be distinguished from cohesive failure and show that the failure mode depends critically on the siderophore analog adsorption density. The adhesion of these molecules to muscovite mica in an aqueous electrolyte solution demonstrates that direct intramolecular adjacency of catechol and cationic functionalities is not necessary for synergistic binding. However, we show that increasing the catechol-cation spacing by incorporating nonbinding domains results in decreased adhesion, which we attribute to a decrease in the density of catechol functionalities. A mechanism for catechol-cation synergy is proposed based on electrostatically driven adsorption and subsequent binding of catechol functionalities. This work should guide the design of new adhesives for binding to charged surfaces in saline environments
Gastrointestinal pathogen distribution in symptomatic children in Sydney, Australia
There is limited information on the causes of paediatric diarrhoea in Sydney. This cross-sectional study used clinical and microbiological data to describe the clinical features and pathogens associated with gastrointestinal illnesses for children presenting to two major public hospitals in Sydney with diarrhoea, for the period January 2007-December 2010.Of 825 children who tested positive for an enteric pathogen, 430 medical records were reviewed. Adenovirus, norovirus and rotavirus were identified in 20.8%, 20.3% and 21.6% of reviewed cases, respectively. Younger children were more likely to have adenovirus and norovirus compared with rotavirus (P=0.001). More viruses were detected in winter than in the other three seasons (P=0.001). Rotavirus presented a distinct seasonal pattern with the lowest rates occurring in the warm months and peaking in the cooler months. Adenovirus showed a less consistent monthly trend, and norovirus detection increased in the cooler months (P=0.008). A decline in the number of rotavirus cases was observed after mid-2008.The majority of childhood diarrhoeal illnesses leading to hospital presentations in Sydney are caused by enteric viruses with most infections following clear seasonal patterns. However, a sustained decrease in the incidence of rotavirus infections has been observed over the study period. © 2012 Ministry of Health, Saudi Arabia
- …