The Influence of Speed on Endurance Tests

Introduction: Intrinsic resistive switching properties of Pt/TiO2-x/TiO2/Pt crossbar memory array has been examined using the crossbar (4×4) arrays fabricated by using DC/RF sputtering under specific conditions at room temperature. Materials and Methods: The growth of filament is envisaged from bottom electrode (BE) towards the top electrode (TE) by forming conducting nano-filaments across TiO2/TiO2-x bilayer stack. Non-linear pinched hysteresis curve (a signature of memristor) is evident from I-V plot measured using Pt/TiO2-x /TiO2/Pt bilayer device (a single cell amongst the 4×4 array is used). It is found that the observed I-V profile shows two distinguishable regions of switching symmetrically in both SET and RESET cycle. Distinguishable potential profiles are evident from I-V curve; in which region-1 relates to the electroformation prior to switching and region-2 shows the switching to ON state (LRS). It is observed that upon reversing the polarity, bipolar switching (set and reset) is evident from the facile symmetric pinched hysteresis profile. Obtaining such a facile switching is attributed to the desired composition of Titania layers i.e. the rutile TiO2 (stoichiometric) as the first layer obtained via controlled post annealing (650oC/1h) process onto which TiO2-x (anatase) is formed (350oC/1h). Results: These controlled processes adapted during the fabrication step help manipulate the desired potential barrier between metal (Pt) and TiO2 interface. Interestingly, this controlled process variation is found to be crucial for measuring the switching characteristics expected in Titania based memristor. In order to ensure the formation of rutile and anatase phases, XPS, XRD and HRSEM analyses have been carried out. Conclusion: Finally, the reliability of bilayer memristive structure is investigated by monitoring the retention (104 s) and endurance tests which ensured the reproducibility over 10,000 cycles.

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Accelerated Aging of Deacidified and Untreated Book Paper in 1967 Compared with 52 Years of Natural Aging

Restaurator International Journal for the Preservation of Library and Archival Material ◽

10.1515/res-2020-0006 ◽

2020 ◽

Vol 41 (3) ◽

pp. 131-152

Author(s):

Tali H. Horst ◽

Richard D. Smith ◽

Antje Potthast ◽

Martin A. Hubbe

Keyword(s):

Room Temperature ◽

Accelerated Aging ◽

Natural Aging ◽

Scanning Electron Micrographs ◽

Surface Ph ◽

Room Temperature Storage ◽

Folding Endurance ◽

Endurance Tests ◽

Breaking Length ◽

Temperature Storage

AbstractThree copies of a book that had been optionally deacidified using two different procedures in 1967, and then subjected to accelerated aging, were tested again after 52 years of natural aging. Matched copies of the book Cooking the Greek Way, which had been printed in Czechoslovakia on acidic paper, were evaluated. Nonaqueous treatment of two of the copies with magnesium methoxide dissolved in chlorofluorocarbon solvent had been found in 1967 to have decreased the susceptibility to embrittlement, as evidenced by the results of the accelerated aging, followed by folding endurance tests. Retesting of the same books in 2019, after 52 years of room temperature storage, showed that the deacidification treatments had achieved the following benefits in comparison to the untreated book: (a) higher brightness; (b) higher folding endurance; (c) tensile breaking length higher in the cross-direction of the paper; (d) substantial alkaline reserve content, (e) an alkaline surface pH in the range 7.1–7.4, and (f) higher molecular mass of the cellulose. Remarkably, some of the folding endurance results matched those of unaged samples evaluated in 1967. Scanning electron micrographs showed no differences between the treated and untreated books.

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Characterization of New Proteomic Biomarker Candidates in Mucopolysaccharidosis Type IVA

International Journal of Molecular Sciences ◽

10.3390/ijms22010226 ◽

2020 ◽

Vol 22 (1) ◽

pp. 226

Author(s):

Víctor J. Álvarez ◽

Susana B. Bravo ◽

Maria Pilar Chantada-Vazquez ◽

Cristóbal Colón ◽

María J. De Castro ◽

...

Keyword(s):

Keratan Sulfate ◽

Bone Lesions ◽

Mucopolysaccharidosis Type ◽

Lysosomal Storage ◽

Protein Biomarkers ◽

Enzyme Replacement ◽

Endurance Tests ◽

Mps Iva ◽

Mucopolysaccharidosis Type Iva ◽

Potential Biomarkers

Mucopolysaccharidosis type IVA (MPS IVA) is a lysosomal storage disease caused by mutations in the N-acetylgalactosamine-6-sulfatase (GALNS) gene. Skeletal dysplasia and the related clinical features of MPS IVA are caused by disruption of the cartilage and its extracellular matrix, leading to a growth imbalance. Enzyme replacement therapy (ERT) with recombinant human GALNS has yielded positive results in activity of daily living and endurance tests. However, no data have demonstrated improvements in bone lesions and bone grow thin MPS IVA after ERT, and there is no correlation between therapeutic efficacy and urine levels of keratan sulfate, which accumulates in MPS IVA patients. Using qualitative and quantitative proteomics approaches, we analyzed leukocyte samples from healthy controls (n = 6) and from untreated (n = 5) and ERT-treated (n = 8, sampled before and after treatment) MPS IVA patients to identify potential biomarkers of disease. Out of 690 proteins identified in leukocytes, we selected a group of proteins that were dysregulated in MPS IVA patients with ERT. From these, we identified four potential protein biomarkers, all of which may influence bone and cartilage metabolism: lactotransferrin, coronin 1A, neutral alpha-glucosidase AB, and vitronectin. Further studies of cartilage and bone alterations in MPS IVA will be required to verify the validity of these proteins as potential biomarkers of MPS IVA.

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