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Aims: Develop a robust and user‐friendly software tool for the prediction of dopamine D2 receptor occupancy (RO) in patients with schizophrenia treated with either olanzapine or risperidone, in order to facilitate clinician exploration of the impact of treatment strategies on RO using sparse plasma concentration measurements. Methods: Previously developed population pharmacokinetic models for olanzapine and risperidone were combined with a pharmacodynamic model for D2 RO and implemented in the R programming language. Maximum a posteriori Bayesian estimation was used to provide predictions of plasma concentration and RO based on sparse concentration sampling. These predictions were then compared to observed plasma concentration and RO. Results: The average (standard deviation) response times of the tools, defined as the time required for the application to predict parameter values and display the output, were 2.8 (3.1) and 5.3 (4.3) seconds for olanzapine and risperidone, respectively. The mean error (95% confidence interval) and root mean squared error (95% confidence interval) of predicted vs. observed concentrations were 3.73 ng/mL (−2.42–9.87) and 10.816 ng/mL (6.71–14.93) for olanzapine, and 0.46 ng/mL (−4.56–5.47) and 6.68 ng/mL (3.57–9.78) for risperidone and its active metabolite (9‐OH risperidone). Mean error and root mean squared error of RO were −1.47% (−4.65–1.69) and 5.80% (3.89–7.72) for olanzapine and −0.91% (−7.68–5.85) and 8.87% (4.56–13.17) for risperidone. Conclusion: Our monitoring software predicts concentration–time profiles and the corresponding D2 RO from sparsely sampled concentration measurements in an accessible and accurate form. [ABSTRACT FROM AUTHOR]

In this article, the suitability of the etchants NaOH/KOH and Ba(OH)2 for defect etching of metalorganic vapour‐phase epitaxy (MOVPE) grown AlN layers with a MgO‐assisted "drop method" is compared. Defect selectivity for the new etchant Ba(OH)2 is confirmed by the local TEM analysis. Temperature dependence (420–500 °C) of etch pit sizes of a‐, mixed‐, and c‐type dislocations for both etchants are investigated by statistical evaluation of scanning electron microscopy (SEM) images. Additionally, the etch pit shape is analyzed for samples etched at 460 °C by atomic force microscopy (AFM) measurements. While a‐ and mixed‐type dislocations result in pits of comparable size and shape for both etchants, c‐type dislocations are already strongly etched with NaOH/KOH at low temperatures leading to over‐etching and MgO precipitation. Ba(OH)2, in contrast, generates smaller c‐type etch pits at low and medium etching temperatures and no MgO precipitates and is therefore preferable for drop etching. [ABSTRACT FROM AUTHOR]

The article focuses on the U.S. Food and Drug Administration (FDA) is to address the high cost of medicines by promoting market competition. Topics include the FDA has announced the Drug Competition Action Plan which aims to remove barriers to generic drug development and encourage timely entry of generic competition, and the FDA has focused its efforts under this plan to improve the efficiency and transparency to the regulatory review process for generic drug applications.