Macroeconomic Regimes

We estimate a New-Keynesian macro model accommodating regime-switching behavior in monetary policy and in macro shocks. Key to our estimation strategy is the use of survey-based expectations for inflation and output. Output and inflation shocks shift to the low volatility regime around 1985 and 1990, respectively. However, we also identify multiple shifts between accommodating and active monetary policy regimes, which play an as important role as shock volatility in driving the volatility of the macro variables. We provide new estimates of the onset and demise of the Great Moderation and quantify the relative role played by macro-shocks and monetary policy. The estimated rational expectations model exhibits indeterminacy in the mean square stability sense, mainly because monetary policy is excessively passive

Proposed Tool to Compare and Assess the Applicability of Taste Assessment Techniques for Pharmaceuticals

Palatability is amongst the most important determinants of whether or not a child will take a medicine. In order to increase concordance with treatment regimens it is often necessary to utilise a range of formulation techniques to improve the palatability of medicines. These can include selecting a different molecule or version of a molecule (such as a different polymorph or salt form), various taste masking techniques and/or the inclusion of flavours and sweeteners. In order to be able to understand the taste of the Active Pharmaceutical Ingredient (API) and to validate the formulation approach used, it is necessary to be able to use the most reliable taste evaluation method possible. Multiple in vivo and in vitro methods exist nowadays or are proposed in the literature but are often little understood by the pharmaceutical product development community. In particular, different methods may be more relevant at different stages of product development. The aim of this article is to propose a tool to guide the selection of the most appropriate method for the desired evaluation. A spreadsheet-based tool is proposed that is designed to allow the systematic assessment of the applicability of any taste assessment technique existing or new to the users proposed application. A series of criteria are defined that will allow the user to assess the analytical, usability and availability factors for the technique that is being considered. Such a systematic review will help the user to understand the benefits and risks of using each methodology for that application. The use of the tool is illustrated based on currently available data and literature. As new/existing methods are developed/improved, the outcomes of the tool may change

Evidence-based nanoscopic and molecular framework for excipient functionality in compressed orally disintegrating tablets

The work investigates the adhesive/cohesive molecular and physical interactions together with nanoscopic features of commonly used orally disintegrating tablet (ODT) excipients microcrystalline cellulose (MCC) and D-mannitol. This helps to elucidate the underlying physico-chemical and mechanical mechanisms responsible for powder densification and optimum product functionality. Atomic force microscopy (AFM) contact mode analysis was performed to measure nano-adhesion forces and surface energies between excipient-drug particles (6-10 different particles per each pair). Moreover, surface topography images (100 nm2-10 μm2) and roughness data were acquired from AFM tapping mode. AFM data were related to ODT macro/microscopic properties obtained from SEM, FTIR, XRD, thermal analysis using DSC and TGA, disintegration testing, Heckel and tabletability profiles. The study results showed a good association between the adhesive molecular and physical forces of paired particles and the resultant densification mechanisms responsible for mechanical strength of tablets. MCC micro roughness was 3 times that of D-mannitol which explains the high hardness of MCC ODTs due to mechanical interlocking. Hydrogen bonding between MCC particles could not be established from both AFM and FTIR solid state investigation. On the contrary, D-mannitol produced fragile ODTs due to fragmentation of surface crystallites during compression attained from its weak crystal structure. Furthermore, AFM analysis has shown the presence of extensive micro fibril structures inhabiting nano pores which further supports the use of MCC as a disintegrant. Overall, excipients (and model drugs) showed mechanistic behaviour on the nano/micro scale that could be related to the functionality of materials on the macro scale. © 2014 Al-khattawi et al

Macroeconomic regimes

A New-Keynesian macro-model is estimated accommodating regime-switching behavior in monetary policy and macro-shocks. A key to our estimation strategy is the use of survey-based expectations for inflation and output. Output and inflation shocks shift to the low volatility regime around 1985 and 1990, respectively. Monetary policy experiences multiple shifts with an important role in shaping macro-volatility. New estimates of the onset and demise of the Great Moderation are provided and the relative role played by macro-shocks and monetary policy is quantified. The estimated rational expectations model exhibits indeterminacy in the mean-square stability sense, mainly due to passive monetary policy