Guns for hire: North America’s intra-continental gun trafficking networks

Objective: to summarize and study the North America’s intra-continental gun trafficking networks.Methods: the work applies social network analysis (SNA) to understand structures, identify brokers and discover patterns in the way guns are being procured, transported across the border, and further distributed.Results: Since Canada adjoins the largest weapons market in the world, it is unsurprising that guns used to commit criminal acts in Canada largely originate in the United States. But how are such weapons transported across the border: by individual entrepreneurs, by small networks, or by sophisticated cartels? This article analyzes six cases that resulted in prosecutions of 40 Canadian and American citizens implicated in Canada-U.S. gun trafficking networks between 2007 and 2010. This study is a plausibility probe that applies social network analysis—investigating networks that come into existence by the creation of pairwise links among their members—to analyze global structures, identify brokers and their roles, and discover patterns in the way guns are being procured in the United States, transported across the border, and distributed in Canada.Scientific novelty: In the process, this study generates hypotheses about network structure and works towards modeling these networks functionally: Since guns are available legally in the United States, we expect to find a proliferation of relatively simple networks. In contrast, drugs, which are not as readily available, might require more sophisticated networks to be trafficked across the border. Results revealed that the trafficking network structures seem to be driven by function. When the objective of the network is mere rent-seeking, transborder trafficking networks for guns tend to be simple. By contrast, when the objective is to manage violence as a constituent element of a larger criminal organization and its activities, networks tend to be more sophisticated, although the gun trafficking networks remain simpler.Practical significance: the main provisions and conclusions of the article can be used in scientific, pedagogical and law enforcement activities when considering the issues related to the illegal firearms trafficking through the US and Canadian territories

Forum on Weathering Steel for Highway Structures: Summary Report

DTFJ61-88-R-00079On July 12-13, 1988 the Office of Research, Development and Technology of the Federal Highway Administration hosted a forum on Weathering Steel for Highway Structures. This conference took place at the Ramada Hotel in Alexandria, Virginia. The major objectives of this forum were to examine the state of the art in weathering steel use and maintenance, to develop rules for its use in new construction, and for maintenance of existing structures. The forum brought together 131 participants representing Federal and State governments and industry. The forum was organized into four main sessions, including a panel discussion and several individual presentations. The report summarizes the forum

Part 1: A Novel Model for Three-Dimensional Culture of 3T3-L1 Preadipocytes Stimulates Spontaneous Cell Differentiation Independent of Chemical Induction Typically Required in Monolayer

Differences in monolayer and three-dimensional (3D) culture systems have been recognized for several years. Despite the recognized importance of 3D systems, low cost and convenience of monolayer culture are still readily used for metabolic and nutritional studies. Here, we present part 1 of a 2-part series that will highlight (1) a novel and cost-effective model for culturing 3T3-L1 preadipocytes in 3D agarose as well as (2) an initial study showing the successful use of this 3D model for experimental analysis of these cells treated with cinnamon extract while suspended in agarose. In part 1, we provide a full characterization of the model system for the 3T3-L1 cells that demonstrate the functionality and convenience of this system. Importantly, we note spontaneous differentiation to adipocytes while cultured under these methods, independent of chemical induction. We present a 2.5-week time course with rounded cells forming vacuoles as early as 24 hours and accumulation of lipid detectable by Oil Red O stain at 0.5 weeks. Serum selection, lipid volume determination, and cell size are characterized. We conclusively demonstrate adipogenesis based on a peroxisome proliferator-activated receptor γ (PPARγ) detection using immunohistochemistry (IHC) of sections from these 3D cultures. Methods, materials and recommendations are described as well as proposed benefits to the use of this culture system for 3T3-L1 cells

Intervertebral disc regeneration: Influence of growth factors on differentiation of human mesenchymal stem cells (hMSC)

Introduction: One common cause of disability in modern society is low back pain. The main reason for this pain is the degeneration of the intervertebral disc (IVD), particular of the nucleus pulposus (NP). For an early degeneration stage cell-based therapy would be a minimal invasive method of treatment. Therefore, adequate cells are needed. As the usage of NP cells is limited because of their insufficient amount or vitality, a promising alternative is the application of human mesenchymal stem cells (hMSCs). Objective: To investigate the potential of various growth factors to induce the differentiation of hMSCs into NP cells and thereby to obtain an alternative cell source for the treatment of IVD degeneration. Methods: hMSC-TERT were cultivated three-dimensionally in a hydrogel for 21 days to form NP cells. Cell survival and proliferation were determined using SybrGreen/propidium iodide double staining and the WST-test. To investigate the ability of several growth factors to differentiate hMSCs into NP cells, fluorescence immunostaining of NP-specific marker proteins (e.g. chondroadherin (CHAD) and the recently discovered cytokeratin 19 [1]) was performed. Results: Following the procedure described above, cells are able to maintain their viability and proliferation capacity throughout the cultivation time. By using a previously established immunofluorescence protocol, we could indicate the ability of three different growth factors to differentiate hMSCs into NP-like cells. Conclusion: The expression of several marker proteins in all differentiation experiments indicates the ability of IGF-1, FGF-2 and PDGF-BB to differentiate hMSCs into NP-like cells apart from the usually applied TGF-β3. Furthermore, our findings preclude the application of Cytokeratin 19 as a specific marker protein for NP cells [1]. Further experiments have to be done to find real specific NP marker proteins to indisputable verify the differentiation of hMSCs into NP cells. If so, application of the mentioned three growth factors would possibly be an option to obtain sufficient NP cells for minimal invasive IVD regeneration