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Based on the large medical data to evaluate the performance of the hearing aid is a promising way. Achieving the classification of the hearing aid is the foundation. In this paper an improved semisupervised AP clustering algorithm based on density path is proposed. The PESQ score is taken as the substitution of subjective score for the speech segments, which is also taken as a semi-supervised basis to improve classification accuracy. The Euclidean distance similarity is improved based on the density path, making it suitable for complex shape data sets. Through experimental verification, compared with the traditional AP algorithm, the improved algorithm shows obvious advantages in terms of hearing aid classification accuracy and recognition performance.

Exploiting micelles of polyethylene glycol–dipalmitoylglycerophosphoethanolamine (PEG–DPPE) as a drug delivery approach is of great promise for improving therapeutic targeting and the half-lives of drugs. To optimize the micelle carriers, pending issues concerning the kinetics underlying the carrier-membrane interplay and the specific contributions of the micelle hydrophobic/hydrophilic components remain to be addressed. Relying on MARTINI coarse-grain (CG) molecular dynamics simulations, we explored the carrier-membrane fusion dynamics of PEG–DPPE micelles with different PEG repetitions in delivering doxorubicin (DOX). A bilayer model composed of 20% phosphatidylglycerol (POPG) and 80% phosphatidylcholine (POPC) was constructed to mimic anionic cancer cell membranes. The CG model of DOX was pioneeringly constructed herein, and it was found to distribute at the hydrophilic/hydrophobic interface of the PEGylated micelles, in agreement with experimental results. The free DOXs cause insignificant disorder of the membrane organization, whereas the PEG–DPPE micelles encapsulating DOX lead to a remarkable membrane invasion supported by the order parameter of the lipid acyl carbon tails and the membrane permeation free energy of DOX. The carrier–bilayer interaction shows a stepwise form attributed to the rearrangement of the zwitterionic/anionic lipids upon the absorption of the DOX-micelle complex on a membrane locality, which initiates the rapid release of DOX to the bilayer interior. Benefiting from the enhanced micelle-membrane interplay, the PEG1250-DPPE micelles result in severe bilayer breakage and deeper membrane insertion of DOX compared to the PEG2000-DPPE micelles. This study provides new theoretical insights into the mechanism of PEG–DPPE micelles in delivering drugs through membranes, which is of benefit for further optimization of PEGylated delivery systems. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2008.03.039 Byline: Ning-Ai Liu (a), Meina Ren (a), Jianbo Song (b), Yesenia Rios (b), Kolja Wawrowsky (a), Anat Ben-Shlomo (a), Shuo Lin (b), Shlomo Melmed (a) Keywords: GFP; green fluorescent protein; POMC; pro-opiomelanocortin; MO; morpholino; FGF; fibroblast growth factors; RPD; rostral pars distalis; PPD; proximal pars distalis; PI; pars intermedia Abstract: The anterior pituitary gland (adenohypophysis) comprises anterior and intermediate lobes (the pars distalis and pars intermedia) arising from placodal ectoderm at the anterior neural ridge. Signaling molecules including SHH, FGF, WNT, BMP and Notch are involved in regulating primordial pituitary proliferation and lineage determination. However, morphogenic events and molecular mechanisms governing anterior and intermediate lobe specification are not clear. Pituitary expression of proopiomelanocortin (POMC), the common precursor for adrenocorticotropin (ACTH) of pars distalis corticotropes and [alpha]-melanocyte-stimulating hormone ([alpha]-MSH) of pars intermedia melanotropes, provides a unique marker for anterior and intermediate lobe morphogenesis. We performed time-lapse confocal microscopy lineage tracing in live zebrafish embryos expressing GFP driven by the pomc promoter and show distinct migration pathways of POMC cells destined to the anterior and intermediate lobes. Using morpholino oligonucleotides, we show that hypomorphic FGF3 down-regulation induces specific defects of pars intermedia POMC cells while pomc, growth hormone and prolactin expression remain intact in the pars distalis. This lineage-specific process is independent of the FGF3 effect on early pituitary specifying transcription factors as indicated by normal Lim3 and Pit1 expression in hypomorphic FGF3 morphants. These findings suggest that the FGF3 signal, in addition to its previously described role of regulating progenitor proliferation and survival, delineates the melanotrope and corticotrope lineage boundary, contributing to establishment of the pituitary pars distalis and pars intermedia. Author Affiliation: (a) Department of Medicine, Cedars-Sinai Research Institute, University of California Los Angeles, Los Angeles, California 90048, USA (b) Department of Molecular, Cell and Developmental Biology, University of California Los Angeles, Los Angeles, California 90048, USA Article History: Received 23 August 2007; Revised 4 March 2008; Accepted 27 March 2008

Correction for 'Delivery mechanism of doxorubicin by PEG–DPPE micelles on membrane invasion by dynamic simulations' by Lina Zhao et al., Phys. Chem. Chem. Phys., 2023, 25, 16114–16125, https://doi.org/10.1039/D2CP05946K. [ABSTRACT FROM AUTHOR]