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A pioneering approach in the domain of transdermal drug delivery systems (TDDS) is introduced by using microneedles (MNs) fabricated from an amorphous solid dispersion comprising only a model drug and an amphiphilic block copolymer to form a drug nanoformulation upon MN dissolution. To maximize drug loading and ensure consistent release, a minimalist formulation that achieves 40 wt% drug loading, which is a significant improvement over existing methods, is developed. Using scanning electron microscopy, the morphology of MNs is examined across a spectrum of drug loading ratios, demonstrating the consistency in structure and integrity. Mechanical testing confirms the MNs' proficiency in effective skin penetration. A comparative study on the formation of polymeric micelles underscores the innovative concept of a "nano‐in‐micro drug delivery system". The results demonstrate that MNs manufactured from an amorphous solid dispersion of drug and amphiphilic block copolymer with ultra‐high loading enhance the availability and release dynamics of hydrophobic drugs, positioning them as a tool for enhancing TDDS. This study sets a new benchmark in the utilization of polymer‐drug nanoformulations for transdermal applications and underscores the capacity for high drug loading and the creation of adaptable drug delivery mechanisms for the studied amphiphilic block copolymer. [ABSTRACT FROM AUTHOR]

Shape optimization with respect to eigenvalues of a cavity plays an important role in the design of new resonators or in the optimization of existing ones. This paper proposes a gradient‐based optimization scheme, which is enhanced with closed‐form shape derivatives of the system matrices. Based on these, accurate derivatives of eigenvalues, eigenmodes, and the cost function can be computed with respect to the geometry, which significantly reduces the computational effort of the optimizer. The work is demonstrated by applying it to the 9‐cell TESLA cavity, for which the design parameters of the computational model are considered as optimization variables to match the design criteria for devices in realistic use cases. Since eigenvalues may cross during the shape optimization of a cavity, a new algorithm based on an eigenvalue matching procedure is proposed, to ensure the optimization of the desired mode in order to also enable successful matching along large shape variations. [ABSTRACT FROM AUTHOR]

Drosophila mutants black and ebony show pigmentation defects in the adult cuticle, which disclose their cooperative activity in β-alanyl-dopamine formation. In visual signal transduction, Ebony conjugates β-alanine to histamine, forming β-alanyl-histamine or carcinine. Mutation of ebony disrupts signal transduction and reveals an electroretinogram (ERG) phenotype. In contrast to the corresponding cuticle phenotype of black and ebony, there is no ERG phenotype observed when black expression is disrupted. This discrepancy calls into question the longstanding assumption of Black and Ebony interaction. The purpose of this study was to investigate the role of Black and Ebony in fly optic lobes. We excluded a presynaptic histamine uptake pathway and confirmed histamine recycling via carcinine formation in glia. β-Alanine supply for this pathway is independent of enzymatic synthesis by Black and β-alanine synthase Pyd3. Two versions of Black are expressed in vivo. Black is a specific aspartate decarboxylase with no activity on glutamate. RNA in situ hybridization and anti-Black antisera localized Black expression in the head. Immunolabeling revealed expression in lamina glia, in large medulla glia, in glia of the ocellar ganglion, and in astrocyte-like glia below the ocellar ganglion. In these glia types, Black expression is strictly accompanied by Ebony expression. Activity, localization, and strict coexpression with Ebony strongly indicate a specific mode of functional interaction that, however, evades ERG detection. J. Comp. Neurol., 521:1207-1224, 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]