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461.
Starch granules were isolated from tubers or leaves of Solanum tuberosum L. and the starch associated proteins were analysed. Based on the solubilisation procedure used, two protein fractions were distinguished: Proteins that are bound to the surface of the starch particles and those enclosed within the granule. A 160 kDa starch associated protein was recovered in both fractions: in starch granule preparations isolated from darkened potato leaves it was predominantly located at the surface of the particle but in tuber starch it was mainly enclosed. In addition, the 160 kDa protein also occurs in a soluble state and resides in the stromal space of amyloplasts from tubers. By using matrix‐assisted laser desorption/ ionisation mass spectrometry (MALDI‐MS) the 160 kDa protein was identified to be the recently described R1 that appears to be involved in phosphorylation and/or degradation of starch. In a screening approach, starch granules and soluble proteins from tubers, seeds and fruits of a variety of plant species were analysed for R1 and the amount of phosphate covalently bound to starch was determined. The level of R1 did not correlate with the content of starch derived phosphate.  相似文献   
462.
Automated segmentation of blood vessels in retinal fundus images is essential for medical image analysis. The segmentation of retinal vessels is assumed to be essential to the progress of the decision support system for initial analysis and treatment of retinal disease. This article develops a new Grasshopper Optimization with Fuzzy Edge Detection based Retinal Blood Vessel Segmentation and Classification (GOFED-RBVSC) model. The proposed GOFED-RBVSC model initially employs contrast enhancement process. Besides, GOAFED approach is employed to detect the edges in the retinal fundus images in which the use of GOA adjusts the membership functions. The ORB (Oriented FAST and Rotated BRIEF) feature extractor is exploited to generate feature vectors. Finally, Improved Conditional Variational Auto Encoder (ICAVE) is utilized for retinal image classification, shows the novelty of the work. The performance validation of the GOFED-RBVSC model is tested using benchmark dataset, and the comparative study highlighted the betterment of the GOFED-RBVSC model over the recent approaches.  相似文献   
463.
Prodigiosenes are a family of red pigments with versatile biological activity. Their tripyrrolic core structure has been modified many times in order to manipulate the spectrum of activity. We have been looking systematically at prodigiosenes substituted at the C ring with alkyl chains of different lengths, in order to assess the relevance of this substituent in a context that has not been investigated before for these derivatives: Cu(II) complexation, DNA binding, self-activated DNA cleavage, photoinduced cytotoxicity and antimicrobial activity. Our results indicate that the hydrophobic substituent has a clear influence on the different aspects of their biological activity. The cytotoxicity study of the Cu(II) complexes of these prodigiosenes shows that they exhibit a strong cytotoxic effect towards the tested tumor cell lines. The Cu(II) complex of a prodigiosene lacking any alkyl chain excelled in its photoinduced anticancer activity, thus demonstrating the potential of prodigiosenes and their metal complexes for an application in photodynamic therapy (PDT). Two derivatives along with their Cu(II) complexes showed also antimicrobial activity against Staphylococcus aureus strains.  相似文献   
464.
Due to its ferroelectricity, hafnium oxide has attracted a lot of attention for ferroelectric memory devices. Amongst different dopant elements, zirconium is found to be beneficial due to the relatively low crystallization temperature of hafnium-zirconium-oxide (HZO), thus it is back-end-of-line (BEoL) compatible. The thickness of HZO has a significant impact on ferroelectric device reliability. High operation temperatures and high endurance are important criteria depending on the application. Herein, various HZO thicknesses (7, 8, and 10 nm) in MFM (metal-ferroelectric-metal) capacitors are investigated at varying operation temperatures (25 to 175 °C) at varying electric fields (±3 to ±5.4 MV cm−1) with respect to polarization, leakage current, endurance, and retention. 7 nm HZO showed promising results with an endurance of 107 cycles, with a low leakage current density, and almost no retention loss after 10 years. Extrapolated results at operation conditions (±2 MV cm−1 and 10 MHz) showed an endurance of 1010 cycles.  相似文献   
465.
This contribution aims to summarize the highlights of the innovations displayed at ACHEMA 2022 and to report on the observed trends. Aside from new equipment in individual areas of drying, the advances of the exhibiting companies in the areas of digitalization and sustainability were examined in greater detail.  相似文献   
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