Formal Specification and Testing of a Management Architecture

The importance of network and distributed systems management to supply and maintain services required by users has led to a demand for management facilities. Open network management is assisted by representing the system resources to be managed as objects, and providing standard services and protocols for interrogating and manipulating these objects. This paper examines the application of formal description techniques to the specification of managed objects by presenting a case study in the specification and testing of a management architecture. We describe a formal specification of a management architecture suitable for scheduling and distributing services across nodes in a distributed system. In addition, we show how formal specifications can be used to generate conformance tests for the management architecture

Tissue-Engineered Three-Dimensional In Vitro Models for Normal and Diseased Kidney

Morphogenesis of epithelial cells involves processes by which kidney shape and function are regulated. The lack of in vitro models that are sustainable for longer time periods and emulating complex intercellular interactions of the kidney have limited understanding about epithelial tissue morphogenesis and its aberrations in diseases such as autosomal dominant polycystic kidney disease (ADPKD). A sustainable three-dimensional (3D) coculture system for normal and diseased kidney tissues is reported here. Tubule- and ADPKD cyst-derived cells were cultured in extracellular matrix molecules infused into 3D porous silk scaffolds, and these cultures were subsequently extended into a perfusion bioreactor. The results indicated collagen–matrigel-mediated morphogenesis for both (normal and disease) cell types and also supported coculturing with fibroblasts. The structural and functional features of the kidney-like tissue structures were validated based on the distribution of E-cadherin, N-cadherin, Na+ K+ ATPase pump, and cellular uptake of the organic anion (6-carboxy fluorescein). Further, the structures were sustained for longer time periods using a perfusion bioreactor to demonstrate the potential utility of this 3D in vitro coculture system for ADPKD research, other epithelial tissue systems, and for in vitro drug screening

A democratic dictator's success: how Chad's President Deby defeated the military opposition in three years (2008–2011)

This is an Accepted Manuscript of an article published by Taylor & Francis in The Journal of Contemporary African Studies on 26 Sep 2013, available online: http://www.tandfonline.com/10.1080/02589001.2013.840974.This article focuses on how President Deby re-gained power after a nearly successful coup d'état against him in February 2008. The analysis points towards one major external reason for success and a divided internal strategy. The international community's little interest in Chad and the desire for political stability among the few interested states are the main external reasons for Deby's success. Internally, Deby's use of violence and co-optation explain his success. Deby defeated the Chadian military opposition by combining co-optation of adversaries in Chad's patrimonial marketplace

China's diversification strategy in Latin American and African markets: Defense software and hardware exports

In the past two decades, China has become a strategic economic partner for both Latin American and African nations. China's economic global relevance is translating via its “Belt and Road Initiative (BRI)” into massive amounts of foreign trade, Foreign Direct Investment (FDI), loans, and aid for both regions. Recently, China has added a national security and defense dimension to its BRI relationship with both regions. China's global strategic economic, geopolitical, and global defense goals are being expressed in its global “Road and Belt” power initiatives and strategies. This paper explores an additional dimension of China's BRI initiative: its role in both regions' defense industries and national security environments. China is increasingly using its trade and investment leverage with both regions to unbalance their defense choices and strategic defense relationships. China's increasing interactions with African and Latin American countries poses a number of geopolitical implications for both the United States and Western European countries.http://wileyonlinelibrary.com/journal/tie2023-04-28hj2022Gordon Institute of Business Science (GIBS

Using formal specifications to support testing

Formal methods and testing are two important approaches that assist in the development of high-quality software. While traditionally these approaches have been seen as rivals, in recent years a new consensus has developed in which they are seen as complementary. This article reviews the state of the art regarding ways in which the presence of a formal specification can be used to assist testing