Hidden geometries in networks arising from cooperative self-assembly

Multilevel self-assembly involving small structured groups of nano-particles provides new routes to development of functional materials with a sophisticated architecture. Apart from the inter-particle forces, the geometrical shapes and compatibility of the building blocks are decisive factors in each phase of growth. Therefore, a comprehensive understanding of these processes is essential for the design of large assemblies of desired properties. Here, we introduce a computational model for cooperative self-assembly with simultaneous attachment of structured groups of particles, which can be described by simplexes (connected pairs, triangles, tetrahedrons and higher order cliques) to a growing network, starting from a small seed. The model incorporates geometric rules that provide suitable nesting spaces for the new group and the chemical affinity $\nu$ of the system to accepting an excess number of particles. For varying chemical affinity, we grow different classes of assemblies by binding the cliques of distributed sizes. Furthermore, to characterise the emergent large-scale structures, we use the metrics of graph theory and algebraic topology of graphs, and 4-point test for the intrinsic hyperbolicity of the networks. Our results show that higher Q-connectedness of the appearing simplicial complexes can arise due to only geometrical factors, i.e., for $\nu = 0$, and that it can be effectively modulated by changing the chemical potential and the polydispersity of the size of binding simplexes. For certain parameters in the model we obtain networks of mono-dispersed clicks, triangles and tetrahedrons, which represent the geometrical descriptors that are relevant in quantum physics and frequently occurring chemical clusters.Comment: 9 pages, 8 figure

Challenges and Trajectories of Fiscal Policy and PFM Reform in CEE/CIS

The purpose of this study is to provide an overview of fiscal policies and PFM reforms in 7 countries in the Western Balkans and 12 countries in the CIS, including major macroeconomic and poverty trends, fiscal policy, the size and role of the public sector, public expenditure management and its linkage to policy development, the organization of budget processes on the central and local levels, the role of various actors and tools in PFM, including civil society and the international donor community. The period of 2003-2007 was characterized by an extraordinary high rate of economic growth, both worldwide and in the CEE/CIS region. This created macroeconomic room for meeting numerous development challenges: reducing poverty and inequality, improving the quality and coverage of public services, upgrading infrastructure, and advancing various reforms, including those related to PFM. However, the economic situation deteriorated dramatically in 2008 as a result of the global financial crisis, with deep recession hitting most of the countries in 2009 and bleak perspectives for subsequent years. It remains to be seen whether the crisis situation will force governments to speed up necessary reforms. In the PFM area major tasks concern lengthening fiscal planning horizon and gradual movement toward performance oriented budgeting the measure which can allow better expenditure targeting and decrease volatility in expenditure allocation), increasing budget transparency and creating real room for civil society involvement into a budget process. However, the reforms must also involve a broadly defined governance sphere, i.e. improving transparency and accountability of government, modernization of civil service, decentralization, including building a genuine system of local and regional self-government, and other similar measures to improve quality of public services and social policy interventions.public finance management, fiscal policy, Central and Eastern Europe, Western Balkans, Commonwealth of Independent States, social policies, social services, children and families

Management of Women — Risk or Opportunity?

A lot has been written about women. Throughout human civilization women have been the foundation of families, but also wars were waged over women, and through marriages friendships were created or expanded, agreements forged between friends, etc. Even today women are the entity, without which one can not imagine the existence of the universe. In other words, evolution is a process in which cells (male and female) are connected resulting in growth and development, but also in the ability to connect with other cells which leads to the formation of living beings, including man as the most complex living being which operates on the principles of selforganization. However, when it comes to politics, business and the general performance of complex and traditional activities that are practiced by men, women are marginalized and discriminated against on numerous issues. Stereotypes and negative attitudes toward business women or women managers have been carefully maintained over centuries. Not far from the truth is statement according to which women must be twice as good as men, to take up important positions in organizations. The aim of this paper is to point out certain indisputable facts when it comes to female management and to answer the question of whether female management is a risk or a chance

Exploring barriers to 'Respondent driven sampling' in sex worker and drug-injecting sex worker populations in Eastern Europe

Respondent driven sampling (RDS) has been used in several counties to sample injecting drug users, sex workers (SWs) and men who have sex with men and as a means of collecting behavioural and biological health data. We report on the use of RDS in three separate studies conducted among SWs between 2004 and 2005 in the Russian Federation, Serbia, and Montenegro. Findings suggest that there are limitations associated with the use of RDS in SW populations in these regions. Findings highlight three main factors that merit further investigation as a means of assessing the feasibility and appropriateness of RDS in this high risk population: the network characteristics of SWs; the appropriate level of participant incentives; and lack of service contact. The highly controlled and hidden nature of SW organizations and weak SW social networks in the region can combine to undermine assumptions underpinning the feasibility of RDS approaches and potentially severely limit recruitment. We discuss the implications of these findings for recruitment and the use of monetary and non-monetary incentives in future RDS studies of SW populations in Eastern Europe

Bacterial iron-oxide nanowires from biofilm waste as a new adsorbent for the removal of arsenic from water

Biofilm, generated by the bacteria in the groundwater pumping system pipelines of the Salt Interception Scheme on the River Murray in South Australia is discarded as a waste material accumulated after periodic cleaning of the pipes. Structural and chemical composition characterizations confirm that this waste material is composed of amorphous twisted iron-oxide nanowires (ION), generated by bacteria, and they have a unique structure and properties. The adsorption performance of these iron-oxide nanowires for arsenic removal from water was evaluated to define their adsorption capacity for As(III) and As(V) and kinetics. Obtained results demonstrate considerable adsorption properties of this waste biological material and suggest its promising application as a new and low-cost adsorbent for water treatment.Ivan Andjelkovic, Sara Azari, Mason Erkelens, Peter Forward, Martin F. Lambert and Dusan Losi

Challenges and trajectories of fiscal policy and PFM reform in CEE/CIS

The purpose of this study is to provide an overview of fiscal policies and PFM reforms in 7 countries in the Western Balkans and 12 countries in the CIS, including major macroeconomic and poverty trends, fiscal policy, the size and role of the public sector, public expenditure management and its linkage to policy development, the organization of budget processes on the central and local levels, the role of various actors and tools in PFM, including civil society and the international donor community. The period of 2003-2007 was characterized by an extraordinary high rate of economic growth, both worldwide and in the CEE/CIS region. This created macroeconomic room for meeting numerous development challenges: reducing poverty and inequality, improving the quality and coverage of public services, upgrading infrastructure, and advancing various reforms, including those related to PFM. However, the economic situation deteriorated dramatically in 2008 as a result of the global financial crisis, with deep recession hitting most of the countries in 2009 and bleak perspectives for subsequent years. It remains to be seen whether the crisis situation will force governments to speed up necessary reforms. In the PFM area major tasks concern lengthening fiscal planning horizon and gradual movement toward performance oriented budgeting (the measure which can allow better expenditure targeting and decrease volatility in expenditure allocation), increasing budget transparency and creating real room for civil society involvement into a budget process. However, the reforms must also involve a broadly defined governance sphere, i.e. improving transparency and accountability of government, modernization of civil service, decentralization, including building a genuine system of local and regional self-government, and other similar measures to improve quality of public services and social policy interventions