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Charlotte, NC, United States

Zhu F.,University of Pennsylvania | Friedman M.S.,University of Pennsylvania | Luo W.,University of Michigan | Luo W.,9201 University City Blvd | And 2 more authors.
Journal of Cellular Physiology | Year: 2012

The transcription factor Osterix (Sp7) is essential for osteoblastogenesis and bone formation in mice. Genome wide association studies have demonstrated that Osterix is associated with bone mineral density in humans; however, the molecular significance of Osterix in human osteoblast differentiation is poorly described. In this study we have characterized the role of Osterix in human mesenchymal progenitor cell (hMSC) differentiation. We first analyzed temporal microarray data of primary hMSC treated with bone morphogenetic protein-6 (BMP6) using clustering to identify genes that are associated with Osterix expression. Osterix clusters with a set of osteoblast-associated extracellular matrix (ECM) genes, including bone sialoprotein (BSP) and a novel set of proteoglycans, osteomodulin (OMD), osteoglycin, and asporin. Maximum expression of these genes is dependent upon both the concentration and duration of BMP6 exposure. Next we overexpressed and repressed Osterix in primary hMSC using retrovirus. The enforced expression of Osterix had relatively minor effects on osteoblastic gene expression independent of exogenous BMP6. However, in the presence of BMP6, Osterix overexpression enhanced expression of the aforementioned ECM genes. Additionally, Osterix overexpression enhanced BMP6 induced osteoblast mineralization, while inhibiting hMSC proliferation. Conversely, Osterix knockdown maintained hMSC in an immature state by decreasing expression of these ECM genes and decreasing mineralization and hMSC proliferation. Overexpression of the Osterix regulated gene OMD with retrovirus promoted mineralization of hMSC. These results suggest that Osterix is necessary, but not sufficient for hMSC osteoblast differentiation. Osterix regulates the expression of a set of ECM proteins which are involved in terminal osteoblast differentiation. © 2011 Wiley Periodicals, Inc. Source

Barcus H.R.,Macalester College | Simmons L.,9201 University City Blvd
Professional Geographer | Year: 2013

Scholars have long documented widespread aging and depopulation of rural communities in the Great Plains. Paralleling these trends is the emergence, growth, and spatial dispersion of new and longtime non-white populations across the region. The dual processes of population loss in many counties combined with the growth of new, non-white population groups suggest that the ethnic structure of the population is changing. In this article we utilize choropleth maps, Hoover and Simpson indexes, and cluster analysis to assess whether the emergence and growth of ethnic minority groups in the Great Plains between 1970 and 2008 is a localized phenomenon or region-wide shift in the ethnic composition of the population. Results suggest that as depopulation is occurring in many counties of this region, the growth of non-white populations, both immigrant and native born, is changing or restructuring the ethnic composition of the Great Plains. © 2013 Copyright Taylor and Francis Group, LLC. Source

Froelich B.,University of North Carolina at Chapel Hill | Bowen J.,9201 University City Blvd | Gonzalez R.,University of North Carolina at Chapel Hill | Snedeker A.,University of North Carolina at Chapel Hill | Noble R.,University of North Carolina at Chapel Hill
Water Research | Year: 2013

Bacteria in the genus Vibrio are ubiquitous to estuarine waters worldwide and are often the dominant genus recovered from these environments. This genus contains several potentially pathogenic species, including Vibrio vulnificus, Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio alginolyticus. These bacteria have short generation times, as low as 20-30min, and can thus respond rapidly to changing environmental conditions. A five-parameter mechanistic model was generated based on environmental processes including hydrodynamics, growth, and death rates of Vibrio bacteria to predict total Vibrio abundance in the Neuse River Estuary of eastern North Carolina. Additionally an improved statistical model was developed using the easily monitored parameters of temperature and salinity. This updated model includes data that covers more than eight years of constant bacterial monitoring, and incorporates extreme weather events such as droughts, storms, and floods. These models can be used to identify days in which bacterial abundance might coincide with increased health risks. © 2013 Elsevier Ltd. Source

Wang Y.,9201 University City Blvd
International Journal of Communication Networks and Distributed Systems | Year: 2011

Distributed control systems (DCS) and supervisory control and data acquisition (SCADA) systems were developed to reduce labour costs, and to allow system-wide monitoring and remote control from a central location. Control systems are widely used in critical infrastructures such as electric grid, natural gas, water and wastewater industries. While control systems can be vulnerable to a variety of types of cyber attacks that could have devastating consequences, little research has been done to secure the control systems. American Gas Association (AGA), IEC TC57 WG15, IEEE, NIST and National SCADA Test Bed Program have been actively designing cryptographic standard to protect SCADA systems. American Gas Association (AGA) had originally been designing cryptographic standard to protect SCADA communication links and finished the report AGA 12 part 1. The AGA 12 part 2 has been transferred to IEEE P1711. This paper presents an attack on the protocols in the first draft of AGA standard (Wright et al., 2004). This attack shows that the security mechanisms in the first version of the AGA standard protocol could be easily defeated. We then propose a suite of security protocols optimised for SCADA/DCS systems which include: point-to-point secure channels, authenticated broadcast channels, authenticated emergency channels, and revised authenticated emergency channels. These protocols are designed to address the specific challenges that SCADA systems have. Copyright © 2011 Inderscience Enterprises Ltd. Source

Arrigo B.A.,9201 University City Blvd
British Journal of Criminology | Year: 2010

This paper conceptually examines one specific case of international terrorism, including the emergence and maintenance of membership-allegiance in its militant extremist group. This is the case of the Islamic Resistance Movement (or Hamas) and the manifestation of its corresponding Palestinian identity. Although the social person is constituted by symbols and objects, acts and social acts, meanings, and role-taking and role-making, questions persist about how best to promote peaceful coexistence, advance the interests of non-violence and ensure the protection of basic human rights. These practices constitute an ethic grounded in Aristotelian virtue. The delineation of key principles emanating from critical restorative justice helps to specify this brand of moral reasoning. The integration of these principles with the proposed symbolic interactionist framework demonstrates how extremist violence can be mediated. Suggestive examples of the same involving Hamas and those with whom it struggles (Palestine, Israel and the United States) are used to guide the analysis. The proposed conceptual framework is then briefly assessed for its overall explanatory capabilities, especially in relation to furthering terrorism studies. © The Author 2009. Source

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