Spatial dispersion in Casimir forces: A brief review

We present the basic principles of non-local optics in connection with the calculation of the Casimir force between half-spaces and thin films. At currently accessible distances $L$, non-local corrections amount to about half a percent, but they increase roughly as 1/L at smaller separations. Self consistent models lead to corrections with the opposite sign as models with abrupt surfaces.Comment: Proceedings of QFEXT05, Barcelona, Sept. 5-9, 200

Pulsar Prospects for the Cherenkov Telescope Array

In the last few years, the Fermi-LAT telescope has discovered over a 100 pulsars at energies above 100 MeV, increasing the number of known gamma-ray pulsars by an order of magnitude. In parallel, imaging Cherenkov telescopes, such as MAGIC and VERITAS, have detected for the first time VHE pulsed gamma-rays from the Crab pulsar. Such detections have revealed that the Crab VHE spectrum follows a power-law up to at least 400 GeV, challenging most theoretical models, and opening wide possibilities of detecting more pulsars from the ground with the future Cherenkov Telescope Array (CTA). In this contribution, we study the capabilities of CTA for detecting Fermi pulsars. For this, we extrapolate their spectra with "Crab-like" power-law tails in the VHE range, as suggested by the latest MAGIC and VERITAS results.Comment: 4 pages, 3 figures. In Proceedings of the 2012 Heidelberg Symposium on High Energy Gamma-Ray Astronomy. All CTA contributions at arXiv:1211.184

Riccati parameter modes from Newtonian free damping motion by supersymmetry

We determine the class of damped modes \tilde{y} which are related to the common free damping modes y by supersymmetry. They are obtained by employing the factorization of Newton's differential equation of motion for the free damped oscillator by means of the general solution of the corresponding Riccati equation together with Witten's method of constructing the supersymmetric partner operator. This procedure leads to one-parameter families of (transient) modes for each of the three types of free damping, corresponding to a particular type of %time-dependent angular frequency. %time-dependent, antirestoring acceleration (adding up to the usual Hooke restoring acceleration) of the form a(t)=\frac{2\gamma ^2}{(\gamma t+1)^{2}}\tilde{y}, where \gamma is the family parameter that has been chosen as the inverse of the Riccati integration constant. In supersymmetric terms, they represent all those one Riccati parameter damping modes having the same Newtonian free damping partner modeComment: 6 pages, twocolumn, 6 figures, only first 3 publishe

Towards democratic intelligence oversight: Limits, practices, struggles

Despite its common usage, The meaning of 'democratic' in democratic intelligence oversight has rarely been spelled out. In this paper, we situate questions regarding intelligence oversight within broader debates about the meanings and practices of democracy. We argue that the literature on intelligence oversight has tended to implicitly or explicitly follow liberal and technocratic ideas of democracy, which have limited the understanding of oversight both in academia and in practice. Thus, oversight is mostly understood as an expert, institutional and partially exclusive arrangement that is supposed to strike a balance between individual freedom and collective security with the goal of establishing the legitimacy of, and trust in intelligence work in a national setting. ‘Healthy’ or ‘efficient’ democratic oversight then becomes a matter of technical expertise, non-partisanship, and the ability to guard secrets. By analysing three moments of struggle around what counts as intelligence oversight across Germany, the UK, and the USA, this paper elucidates their democratic stakes. Through a practice-based approach, we argue that oversight takes much more agonistic, contentious, transnational, and public forms. However, these democratic practices reconfiguring oversight remain contested or contained by dominant views on what constitutes legitimate and effective intelligence oversight

Onset of Phase Synchronization in Neurons Conneted via Chemical Synapses

We study the onset of synchronous states in realistic chaotic neurons coupled by mutually inhibitory chemical synapses. For the realistic parameters, namely the synaptic strength and the intrinsic current, this synapse introduces non-coherences in the neuronal dynamics, yet allowing for chaotic phase synchronization in a large range of parameters. As we increase the synaptic strength, the neurons undergo to a periodic state, and no chaotic complete synchronization is found.Comment: to appear in Int. J. Bif. Chao

Assessing Risk and Sustainability Factors in Spice Supply Chain Management

The inopportune organization of spice supply chains (SSCs) results in aided risks, resource wastages, and sustainability issues. Nevertheless, practitioners and academicians alike must investigate spice supply chain management (SSCM) in terms of long-term sustainability. This study draws on the available literature to compile a collection of characteristics and maintain sustainable spice supply chain management techniques which come up with associated risks and relevant obstacles. Existing studies claim that due to a lack of resources, the associated risks are the root of poor SSCM performance. As a result, the goal of this study is to identify the primary risk variables using qualitative data; nevertheless, the attributes must be converted into a scale that is comparable. The fuzzy Delphi method (FDM) was used to obtain valid and reliable attributes from qualitative data, while the fuzzy decision-making trial and evaluation laboratory (FDEMATEL) was used to address uncertainty and interrelationships simultaneously. FDM results suggest that there are eighteen critical risk variables and seven risks threatening effective SSCM. FDEMATEL results reveal qualitative data translated into crisp, comparable values in order to investigate causal linkages between variables and confirm the compatibility of the theoretical structure with industry realities. The findings show fluctuation in the Price (C8), diseases and pests (C20), human contamination (C23), spice adulteration (C24), and loss of food quality, and quantity (C36) are all important risks and sub-risks in these causative interrelationships. The primary risks involved in enhancing SCM include Financial Risk (A5), Ergonomic Risk (A8), and Operation and Management Risk (A10). The study recommends that industry professionals use future marketing tools to protect themselves from price changes which allow them to assess supply and demand circumstances and manage price risks over distance and time. Spices are the key contributors to earning a sizable amount of foreign currency through export in a developing country. It suggests to policymakers, regulatory organizations, and practitioners to develop regulations, raise farmer understanding about pest control, impose stiff penalties on vendors and businesses proven to be involved in spice adulteration, and develop a sustainable fertilizer distribution system. These corresponding action plans for improving the SSC sector and comparing it with agro-food and short-supply chains are investigated. This study contributes to theory by utilizing FDM and FDEMATEL methods for addressing the uncertainty and interrelationship among associated risks that hinder SCM from attaining sustainability