This paper analyzes the impact on mobile telephony diffusion patterns of the two predominant payment regimes, calling party pays (CPP) and receiving party pays (RPP), for mobile termination services. By applying instrumental variable techniques to panel data we account for a possible interdependency of penetration rates and regulatory interventions. For this purpose we use data on political and...

It is important for search and pay-per-click engines to penetration test their click fraud detection systems, in order to find potential vulnerabilities and correct them before fraudsters can exploit them. In this paper, we describe: (1) some goals and desirable qualities of a click fraud penetration testing system, based on our experience, and (2) our experiences with the challenges of buildin...

Soil stiffness constants govern the soil sinkage and the pressure-sinkage behaviour of the soil under load. To determine soil stiffness constants in Upadhyaya model under field conditions, a field reflecting general character of an agricultural soil was selected and multiplate penetration tests were conducted. The soil stiffness constants in Upadhyaya model were determined from five sets of soi...

The transdermal delivery system (TDS) is able to obtain a systemic therapeutic effect by administration through the skin, which has low side effects and is able to maintain a sustained blood concentration. However, due to the barrier presented by the stratum corneum, numerous drugs have poor percutaneous permeability. Therefore, the improvement of skin permeability is key to TDS. The main metho...

AIM The aim of this in vitro study was to investigate the cervical microleakage and internal voids of nanocomposites comparing them with a hybrid composite in Class II restorations with the margins located coronal and apical to the cementoenamel junction (CEJ). METHODS AND MATERIALS Standardized MOD cavities (one cervical margin located in dentin, one in enamel) were prepared in 40 extracted ...

BACKGROUND Evaluation of microleakage is important for assessing the success of new methods for surface preparation and new adhesive restorative materials. The aim of this laboratory study was to assess microleakage at the margins of composite restorations in Er,Cr:YSGG laser prepared cavities on the cervical aspects of teeth by means of dye penetration, and compare this with conventionally pre...