849 research outputs found
The Regional Origins of the Libyan Conflict
We explore the effects of Libya's administrative division into Tripolitania, Cyrenaica, and Fezzan on the onset of the Libyan conflict. We argue that Tripolitania and Cyrenaica, in particular, followed two different and distinct paths of political development and socioeconomic transformation. While Tripolitania and its elites are connected to the core of Libyan statehood and the legacies of Italian colonization, Cyrenaica is defined by localized political autonomy and economic autarky with respect to natural resources. Furthermore, the Qadhafi regime marginalized Cyrenaica politically, despite its major significance for the Libyan economy, because of its strong royalist inclinations. By offering an overview of Libya's political evolution and socioeconomic development, we indicate that the current conflict has largely been due to the asymmetric and artificial dominance of Tripolitania over the other two regions, particularly Cyrenaica
A structured methodology for enterprise modeling: a case study for modeling the operation of a British organization
BIOACTIVITY OF ANTIDESMA BUNIUS LEAVES (EUPHORBIACEAE) AND THEIR MAJOR PHENOLIC CONSTITUENTS
Chromatographic fractionation of the methanol extract of Antidesma bunius leaves afforded six polyphenols, namely, corilagin (1), gallic (2), ferrulic (3) and ellagic (4) acids in addition to the flavone vicinin II (5) and the dimmer amentoflavone (6). Their structures were elucidated by NMR and HRESI analysis. This is the first reported occurrence of the biflavone (amentoflavone) and vicinin in this species. The total phenolic content was estimated at 90 mg/ml of gallic acid equivalent (GAE) per 100 g plant extract using the Folin-Ciocalteu method. Antioxidant biochemical assay of the plant methanol extract was carried out using culture medium of hepatocyte cell lines. An increase in glutathione reductase enzyme and a reduction of the nitric oxide level in the cell culture revealed that A. bunius leaf extract possesses significant antioxidant activity in comparing with quercetine as a reference. The hepatotoxicity and hepatoprotective activities of A.bunius leaf extract and the pure isolated compounds: 1 , 2 and 5 were evaluated by adopting the MTT colorimetric assay. Compounds 1 and 2 revealed a margin of safety on the monolayer hepatocyte with an IC50 > 1000 μg/ml while for 5, IC50 was at 125 μg/ml. The hepatoprotective activities for A.bunius leaf extract, 1 and 2 in comparison to Silymarin (50 μg/ml) were at 6.5, <12.5 and 12.5 μg/ml respectively while 5 did not show hepatoprotective activity at the tested concentrations
A predator-prey mathematical model with competitive interaction amongst two species
A mathematical model is constructed to study the effect of predation on two competing species in which one of the competing species is a prey to the predator whilst the other species is not under predation.  We assume that all species can move by diffusion and study the spatial structure of the species and obtained conditions for the existence and stability of equilibrium solutions. The results indicate the possibility of a stable coexistence of the three interacting species in form of stable oscillations under the reflecting boundary conditions.  Numerical simulations supported our theoretical predictions.  By utilizing Liapunov-like functions and differential inequalities we were able to establish that the system is dissipative
A Framework for Construction Workspace Management: A Serious Game Engine Approach
Construction workspace is regarded as one of the main constraints on construction sites. Construction workspaces are generally difficult to proactively plan and manage due to the dynamic nature of a site where workspace requirements keep changing as time evolves. However, project managers are looking for ways to develop proactive site plan for the workspaces required for construction activities as this can impact not only on the cost and project duration, but can also contribute to provide a safer site. This research paper presents an approach for integrating workspace management within the planning process using a serious game engine technology. This paper first illustrates a review of the workspace management practices and advanced visualization techniques in the construction industry. Then, it presents a process framework for an interactive decision support system that integrates workspace planning into 5D planning in order to enable safer, efficient and more productive construction sites. The decision support system will identify schedule conflicts, workspace conflicts and the severity of their conflicts, and workspace congestions on a construction site and allow construction planners to resolve spatial conflicts prior to construction. Finally, the paper shows the current progress in the development of an initial prototype and outlines the future work and research. © 2012 American Society of Civil Engineers
Molecular Modeling of Disease Causing Mutations in Domain C1 of cMyBP-C
Cardiac myosin binding protein-C (cMyBP-C) is a multi-domain (C0-C10) protein that regulates heart muscle contraction through interaction with myosin, actin and other sarcomeric proteins. Several mutations of this protein cause familial hypertrophic cardiomyopathy (HCM). Domain C1 of cMyBP-C plays a central role in protein interactions with actin and myosin. Here, we studied structure-function relationship of three disease causing mutations, Arg177His, Ala216Thr and Glu258Lys of the domain C1 using computational biology techniques with its available X-ray crystal structure. The results suggest that each mutation could affect structural properties of the domain C1, and hence it's structural integrity through modifying intra-molecular arrangements in a distinct mode. The mutations also change surface charge distributions, which could impact the binding of C1 with other sarcomeric proteins thereby affecting contractile function. These structural consequences of the C1 mutants could be valuable to understand the molecular mechanisms for the disease
The Interplay between Linear Representations of the Braid Group
We consider Wada's representation as a twisted version of the standard action of the braid group, Bn, on the free group with n generators. Constructing a free group, Gnm, of rank nm, we compose Cohen's map Bn→Bnm and the embedding Bnm→Aut(Gnm) via Wada's map. We prove that the composition factors of the obtained
representation are one copy of Burau representation and m−1 copies of the standard representation after changing the parameter t to tk in the definitions of the Burau and standard representations. This is a generalization of our previous result concerning the standard Artin representation of the braid group
Assessment of seismic scenario-structure based limit state criteria for a reinforced concrete high-rise building
Issues regarding reinforced concrete (RC) high-rise buildings involve different seismic scenarios, such as near- and far-field earthquakes, which can result in different levels and complex seismic scenario structures related to global damage. This study aims to evaluate the seismic scenario structures of a 23-storey RC high-rise building based on different damage measures and to develop a fragility curve with different limit state criteria. Six ground motions are selected to represent two seismic scenarios. Seismic scenario-based global response of the building at increasing earthquake intensity measures is adopted using incremental dynamic analysis (IDA). IDA curves and interstorey drift are used in the parametric study. The structural performance and damage measure of RC high-rise buildings are evaluated with performance-based seismic design limit state. The four performance levels proposed by ATC-43 are operational performance, immediate occupancy, life safety and collapse prevention. The IDA curves showed that near-field effect has a high frequency that gives impact at early intensity measures on building collapse compared with far-field effect. Meanwhile, interstorey drift result indicates that the near-field effect has a larger effect on building damages compared with the far-field effect. Based on the fragility curves, near-field earthquakes have a larger effect towards structural damages than far-field earthquakes
Examining the eye movement behaviors associated with skilled decision-making by elite Australian Rules Football players
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