Yamamoto M.,University of Wisconsin-La Crosse |
Kushin M.J.,Shepherd University
Journal of Computer-Mediated Communication | Year: 2014
This study examines the ways in which online media influenced political disaffection among young adults during the 2008 presidential election campaign. The effects of social media attention, online expression, and traditional Internet sources on political cynicism, apathy, and skepticism were evaluated using data from an online survey of college students. Results show that attention to social media for campaign information is positively related to cynicism and apathy and negatively related to skepticism. Online expression has a positive effect on skepticism. Implications are discussed for the role of social media in bringing a historically disengaged demographic into the political process. © 2013 International Communication Association.
Wang Q.,Shepherd University |
Liu X.,University of Waterloo
Journal of the Franklin Institute | Year: 2012
This paper investigates stability problems of a class of nonlinear impulsive switching systems with time-varying delays. Based on the common Lyapunov function method and Razumikhin technique, several stability criteria are established for nonlinear impulsive switching systems with time-varying delays. Our results show that switching systems can be stabilized by impulsive switching signals even if the system matrices are all unstable. In the absence of impulses, some of our results reduce to similar stability criteria for nonimpulsive switching systems in some recent research articles. Several examples with simulations are given to illustrate the efficiency of our results. © 2011 The Franklin Institute.
Groff J.R.,Shepherd University
American Journal of Physics | Year: 2013
The logistic map difference equation is encountered in the theoretical ecology literature as a mathematical model of population change for organisms with non-overlapping generations and density-dependent dynamics influenced solely by intraspecific interactions. This article presents the logistic map as a simple model suitable for introducing students to the properties of dynamical systems including periodic orbits, bifurcations, and deterministic chaos. After a brief historical and mathematical introduction to models of population change and the logistic map, the article summarizes the logistic map activities I teach in my introductory physics laboratories for non-physics majors. The logistic map laboratory introduces the many bioscience students in my courses to a foundational model in population ecology that has inspired ecologists to recognize the importance of nonlinear dynamics in real populations. Although I use this activity in courses for non-majors, the logistic map model of population change could also be taught to physics majors to introduce properties of dynamical systems while demonstrating an application of mathematical modeling outside of traditional physics. © 2013 American Association of Physics Teachers.
Amiraslani A.,Shepherd University
International Journal of Computer Mathematics | Year: 2011
We show that using the constrained Rayleigh quotient method to find the eigenvalues of matrix polynomials in different polynomial bases is equivalent to applying the Newton method to certain functions. We find those functions explicitly for a variety of polynomial bases including monomial, orthogonal, Newton, Lagrange and Bernstein bases. In order to do so, we provide explicit symbolic formulas for the right and left eigenvectors of the generalized companion matrix pencils for matrix polynomials expressed in those bases. Using the properties of the Newton basis, we also find two different formulas for the companion matrix pencil corresponding to the Hermite interpolation. We give pairs of explicit LU factors associated with these pencils. Additionally, we explicitly find the right and left eigenvectors for each of these pencils. © 2011 Taylor & Francis.
Montepare J.M.,Lasell College |
Dobish H.,Shepherd University
Journals of Gerontology - Series B Psychological Sciences and Social Sciences | Year: 2014
Objectives. Although theorists acknowledge that beliefs about emotions may play a role in age-related emotion behavior, no research has explored these beliefs. This research examined beliefs about the experience and expression of emotions across the life span, especially across the adult years.Method s. Younger and older adults rated the extent to which infants, children, adolescents, young adults, middle-aged adults, and older adults were likely to experience and express a range of emotions.Results. Younger and older adults held similar beliefs about the course of emotions across the life span. Moreover, these beliefs differed across emotion categories. In particular, although older adults were believed to experience and express fewer highly charged, negative emotions, they were expected to be more likely to experience and express positive, low arousal emotions, as well as negative, low arousal emotions. The experience and expression of positive, high arousal emotions were seen as more characteristic of very young age groups as opposed to older age groups.Discussion. These findings beg questions about if and how beliefs about emotion may affect age-related emotion regulation strategies and other everyday emotion-focused behaviors, as well as social reactions to older adults observed experiencing and expressing particular types of emotions. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved.
Clayton L.H.,Shepherd University
Nutrition in Clinical Practice | Year: 2010
Nutrition and diet therapy are at the center of health promotion activities and self-management of chronic diseases. To assist an individual in making informed decisions regarding his or her diet and increase adherence to dietary recommendations or treatments, healthcare professionals must select health information that is appropriate to the client's level of understanding. A systematic approach in the evaluation of patient education material, whether in print or on the World Wide Web, must focus on the information's content, literacy level, graphical displays, layout and typography, motivating principles, cultural relevance, and feasibility. Additional criteria should be evaluated when accessing Web sites and include source, site credibility, conflict of interest, disclaimer, disclosure, navigation, and interactivity information. © 2010 American Society for Parenteral and Enteral Nutrition.
Zhang Y.,Nanjing Normal University |
Wang S.,Nanjing Normal University |
Wang S.,Nanjing University |
Phillips P.,Shepherd University |
Ji G.,Nanjing Normal University
Knowledge-Based Systems | Year: 2014
In this paper, we proposed a novel spam detection method that focused on reducing the false positive error of mislabeling nonspam as spam. First, we used the wrapper-based feature selection method to extract crucial features. Second, the decision tree was chosen as the classifier model with C4.5 as the training algorithm. Third, the cost matrix was introduced to give different weights to two error types, i.e., the false positive and the false negative errors. We define the weight parameter as α to adjust the relative importance of the two error types. Fourth, K-fold cross validation was employed to reduce out-of-sample error. Finally, the binary PSO with mutation operator (MBPSO) was used as the subset search strategy. Our experimental dataset contains 6000 emails, which were collected during the year of 2012. We conducted a Kolmogorov-Smirnov hypothesis test on the capital-run-length related features and found that all the p values were less than 0.001. Afterwards, we found α = 7 was the most appropriate in our model. Among seven meta-heuristic algorithms, we demonstrated the MBPSO is superior to GA, RSA, PSO, and BPSO in terms of classification performance. The sensitivity, specificity, and accuracy of the decision tree with feature selection by MBPSO were 91.02%, 97.51%, and 94.27%, respectively. We also compared the MBPSO with conventional feature selection methods such as SFS and SBS. The results showed that the MBPSO performs better than SFS and SBS. We also demonstrated that wrappers are more effective than filters with regard to classification performance indexes. It was clearly shown that the proposed method is effective, and it can reduce the false positive error without compromising the sensitivity and accuracy values. © 2014 Elsevier B.V. All rights reserved.
Hendrickson S.L.,Shepherd University
BMC Evolutionary Biology | Year: 2013
Background: Life at high altitude results in physiological and metabolic challenges that put strong evolutionary pressure on performance due to oxidative stress, UV radiation and other factors dependent on the natural history of the species. To look for genes involved in altitude adaptation in a large herbivore, this study explored genome differentiation between a feral population of Andean horses introduced by the Spanish in the 1500s to the high Andes and their Iberian breed relatives. Results: Using allelic genetic models and Fst analyses of ∼50 K single nucleotide polymorphisms (SNPs) across the horse genome, 131 candidate genes for altitude adaptation were revealed (Bonferoni of p ≤ 2 × 10-7). Significant signals included the EPAS1 in the hypoxia-induction-pathway (HIF) that was previously discovered in human studies (p = 9.27 × 10-8); validating the approach and emphasizing the importance of this gene to hypoxia adaptation. Strong signals in the cytochrome P450 3A gene family (p = 1.5 ×10-8) indicate that other factors, such as highly endemic vegetation in altitude environments are also important in adaptation. Signals in tenuerin 2 (TENM2, p = 7.9 × 10 -14) along with several other genes in the nervous system (gene categories representation p = 5.1 × 10-5) indicate the nervous system is important in altitude adaptation. Conclusions: In this study of a large introduced herbivore, it becomes apparent that some gene pathways, such as the HIF pathway are universally important for high altitude adaptation in mammals, but several others may be selected upon based on the natural history of a species and the unique ecology of the altitude environment. © 2013 Hendrickson; licensee BioMed Central Ltd.
Dixit P.,American University of Washington |
Stump J.L.,Shepherd University
Studies in Conflict and Terrorism | Year: 2011
In their recent article"We're all terrorists now: critical or hypocritical studies on terrorism?" David Martin Jones and M. L. R. Smith strongly criticize Critical Terrorism Studies (CTS) for a series of reasons, including a lack of evidence for CTS claims, an over-focus on deconstruction and emancipation combined with an under focus on explanation, and an ethically dubious relativism. In this response, we agree with many of Jones and Smith's criticisms. However, where Jones and Smith see these criticisms as undermining CTS,we interpret the concerns very differently. Instead of indicating unfixable problems, we note these issues as presenting opportunities for CTS to further develop a methodologically rigorous empirical research program. We draw on Jones and Smith's criticisms of CTS to point toward five areas of development for terrorism studies in general and CTS in particular. © Taylor & Francis Group, LLC.
News Article | December 19, 2016
Chris and Tim have known each other since high school. They started their Frederick, MD franchise in March 1999 after connecting with a U.S. Lawns franchisee nearby. Both were about 20 years old and had been working for other companies - Chris trimming trees and Tim doing residential lawn work. They wanted to own their own business. With a truck, mower, weedeater and a chain saw to start with, they had a vision. They attended a U.S. Lawns Annual Conference before signing their franchisee agreement. They liked what they saw, signed, and they hit the ground running from day one. Seeking ways to generate a bigger base, they purchased their second territory in Winchester, VA in early 2015. Hiring the right people was key. Austin Elliott was a perfect choice to lead the charge in Winchester, equipped with a BS in environmental studies from Shepherd University. And within six months, they were happy with the income and it continues to grow. Chris and Tim have built their businesses utilizing the tools and systems of U.S. Lawns. Their 16 years of experience with agronomics, providing quality, professional grade service and building great customer relationships have given them a depth of knowledge that is a very valuable resource. They are always glad to give sage advice about the green or the snow management industry to newer franchisees, as they are also very successful in the snow & ice management business and are respected by their peers as experts. U.S. Laws President Ken Hutcheson joined U.S. Lawns in 1995 and helped grow the company from a regional 18-franchise network to an industry leader with over 250 commercial landscape management franchises nationwide offering year-round grounds services. To honor his longevity and commitment to the company in its 30th anniversary year, Ken was inducted into the U.S. Lawns Hall of Fame. “I was proud to see Tim Harrell and Chris Seaborne inducted into the U.S. Lawns Hall of Fame," said Ken Hutcheson. "Watching them over the years grow as individuals, grow their families, grow their team, and grow their business has been inspiring to me and many others. They are a great example of what this industry, this country, and U.S. Lawns offers people who are willing to commit to a dream and work diligently to turn that dream into reality.” Hall of Fame members are individuals who exemplify the mission and vision of U.S. Lawns. This is the company’s most prestigious award. About U.S. Lawns Founded in 1986, U.S. Lawns services commercial landscape customers through a network of over 250 locally owned franchise locations nationwide, providing customized landscape management and snow & ice management services to corporate campuses, retail centers, industrial parks, multi-family residential communities and other commercial customers. For more information, visit http://www.USLawns.com and http://www.USLawnsFranchise.com.