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61.
Andrzej Taube Robert Mroczyński Katarzyna Korwin-Mikke Sylwia Gierałtowska Jan Szmidt Anna Piotrowska 《Materials Science and Engineering: B》2012,177(15):1281-1285
In this work, we report on effects of post-deposition annealing on electrical characteristics of metal–insulator–semiconductor (MIS) structures with HfO2/SiO2 double gate dielectric stacks. Obtained results have shown the deterioration of electro-physical properties of MIS structures, e.g. higher interface traps density in the middle of silicon forbidden band (Ditmb), as well as non-uniform distribution and decrease of breakdown voltage (Ubr) values, after annealing above 400 °C. Two potential hypothesis of such behavior were proposed: the formation of interfacial layer between hafnia and silicon dioxide and the increase of crystallinity of HfO2 due to the high temperature treatment. Furthermore, the analysis of conduction mechanisms in investigated stacks revealed Poole–Frenkel (P–F) tunneling at broad range of electric field intensity. 相似文献
62.
Iwona Mazur-Michaek Katarzyna Kowalska Daniel Zielonka Marta Leniczak-Staszak Paulina Pietras Witold Szaflarski Mark Isalan Michal Mielcarek 《International journal of molecular sciences》2022,23(10)
Huntington’s disease (HD) is a fatal neurodegenerative disorder caused by a polyglutamine expansion in the huntingtin protein. HD-related pathological remodelling has been reported in HD mouse models and HD carriers. In this study, we studied structural abnormalities in the optic nerve by employing Spectral Domain Optical Coherence Tomography (SD-OCT) in pre-symptomatic HD carriers of Caucasian origin. Transmission Electron Microscopy (TEM) was used to investigate ultrastructural changes in the optic nerve of the well-established R6/2 mouse model at the symptomatic stage of the disease. We found that pre-symptomatic HD carriers displayed a significant reduction in the retinal nerve fibre layer (RNFL) thickness, including specific quadrants: superior, inferior and temporal, but not nasal. There were no other significant irregularities in the GCC layer, at the macula level and in the optic disc morphology. The ultrastructural analysis of the optic nerve in R6/2 mice revealed a significant thinning of the myelin sheaths, with a lamellar separation of the myelin, and a presence of myelonoid bodies. We also found a significant reduction in the thickness of myelin sheaths in peripheral nerves within the choroids area. Those ultrastructural abnormalities were also observed in HD photoreceptor cells that contained severely damaged membrane disks, with evident vacuolisation and swelling. Moreover, the outer segment of retinal layers showed a progressive disintegration. Our study explored structural changes of the optic nerve in pre- and clinical settings and opens new avenues for the potential development of biomarkers that would be of great interest in HD gene therapies. 相似文献
63.
Arc-evaporated CrN, CrN and CrCN coatings 总被引:2,自引:0,他引:2
The results of investigations of some tribological properties of chromium nitride, carbonitride and carbide films, prepared by cathodic arc-evaporation method (CAE) are presented in this article. The chemical composition of films was determined by the WDXs and EDXs. The different carbon content was obtained by using nitrogen and acetylene mixtures of various concentrations as the deposition atmosphere. The carbon content was ranging from 0 to 53 at.%. The adhesion of CrCN films was estimated from the analysis of scratch-test results comprising tangential (friction) force, acoustic emission and morphology of scratch surface. The films showed very good adhesion to steel substrates, expressed by Lc (critical load) value, as high as 90 N for carbon free films. The Lc decreased slightly as the carbon content increased. The hardness of films was investigated as a function of carbon content and was estimated by Jönsson-Hogmark method. The Lc value and hardness seem to be correlated in the same way with carbon content. The highest hardness (30 GPa) was obtained for CrN films, while carbon rich films (CrC) showed hardness at the level of 20 GPa. The tribological tests were performed in the ball-on-disk geometry in room air under the load of 1 N and 10 N. The wear rate of investigated films increased with carbon content above 20 at.%. The maximum value of the friction coefficient was 0.55, the same as for CrN films. It decreased to 0.33 as the carbon content increased. 相似文献
64.
Katarzyna Wykpis Magdalena Popczyk Antoni Budniok 《Bulletin of Materials Science》2011,34(4):997-1001
Zn-Ni coatings were deposited under galvanostatic conditions on steel substrate (OH18N9). The influence of current density
of deposition on the surface morphology, chemical and phase composition was investigated. The corrosion resistance of Zn-Ni
coatings obtained at current density 10–25 mA cm−2 are measured, and are compared with that of metallic cadmium coating. Structural investigations were performed by the X-ray
diffraction (XRD) method. The surface morphology and chemical composition of deposited coatings were studied using a scanning
electron microscope (JEOL JSM-6480) with EDS attachment. Studies of electrochemical corrosion resistance were carried out
in the 5% NaCl, using potentiodynamic and electrochemical impedance spectroscopy (EIS) methods. On the ground of these research,
the possibility of deposition of Zn-Ni coatings contained 24–26% at. Ni was exhibited. It was stated, that surface morphology,
chemical and phase composition of these coatings are practically independent on current density of deposition. On the basis
of electrochemical investigations it was found that corrosion resistance of these Zn-Ni coatings is also independent of current
density. These coatings are more corrosion resistant in 5% NaCl solution than metallic cadmium. It was suggested that the
Zn-Ni coating may be used as a substitute for toxic cadmium. 相似文献
65.
Natalia Janicka Agnieszka Saek Magdalena Sawiska Ernest Kuchar Anna Wiela-Hojeska Katarzyna Karowicz-Bodalska 《International journal of molecular sciences》2022,23(13)
Skin and gastrointestinal cancer cells are the target of research by many scientists due to the increasing morbidity and mortality rates around the world. New indications for drugs used in various conditions are being discovered. Non-opioid analgesics are worth noting as very popular, widely available, relatively cheap medications. They also have the ability to modulate the membrane components of tumor cells. The aim of this review is to analyze the impact of diclofenac, ibuprofen, naproxen, acetylsalicylic acid and paracetamol on skin and gastrointestinal cancers cell membrane. These drugs may affect the membrane through topical application, at the in vitro and in vivo level after oral or parenteral administration. They can lead to up- or downregulated expression of receptors, transporters and other molecules associated with plasma membrane. Medications may also alter the lipid bilayer composition of membrane, resulting in changes in its integrity and fluidity. Described modulations can cause the visualization of cancer cells, enhanced response of the immune system and the initiation of cell death. The outcome of this is inhibition of progression or reduction of tumor mass and supports chemotherapy. In conclusion, non-opioid analgesics may be used in the future as adjunctive therapy for the treatment of these cancers. 相似文献
66.
Artur Bekaa Wodzimierz Potek Dorota Siwicka-Gieroba Joanna Soek-Pastuszka Romuald Bohatyrewicz Jowita Biernawska Katarzyna Kotfis Magdalena Bielacz Andrzej Jaroszyski Wojciech Dabrowski 《International journal of molecular sciences》2022,23(13)
Brain injury, especially traumatic brain injury (TBI), may induce severe dysfunction of extracerebral organs. Cardiac dysfunction associated with TBI is common and well known as the brain–heart crosstalk, which broadly refers to different cardiac disorders such as cardiac arrhythmias, ischemia, hemodynamic insufficiency, and sudden cardiac death, which corresponds to acute disorders of brain function. TBI-related cardiac dysfunction can both worsen the brain damage and increase the risk of death. TBI-related cardiac disorders have been mainly treated symptomatically. However, the analysis of pathomechanisms of TBI-related cardiac dysfunction has highlighted an important role of melatonin in the prevention and treatment of such disorders. Melatonin is a neurohormone released by the pineal gland. It plays a crucial role in the coordination of the circadian rhythm. Additionally, melatonin possesses strong anti-inflammatory, antioxidative, and antiapoptotic properties and can modulate sympathetic and parasympathetic activities. Melatonin has a protective effect not only on the brain, by attenuating its injury, but on extracranial organs, including the heart. The aim of this study was to analyze the molecular activity of melatonin in terms of TBI-related cardiac disorders. Our article describes the benefits resulting from using melatonin as an adjuvant in protection and treatment of brain injury-induced cardiac dysfunction. 相似文献
67.
Kamila Checinska Maciej Checinski Katarzyna Cholewa-Kowalska Maciej Sikora Dariusz Chlubek 《International journal of molecular sciences》2022,23(13)
One of the possible alternatives for creating materials for the regeneration of bone tissue supporting comprehensive reconstruction is the incorporation of active substances whose controlled release will improve this process. This systematic review aimed to identify and synthesize in vitro studies that assess the suitability of polyphenolics as additives to polymer-ceramic composite bone regeneration materials. Data on experimental studies in terms of the difference in mechanical, wettability, cytocompatibility, antioxidant and anti-inflammatory properties of materials were synthesized. The obtained numerical data were compiled and analyzed in search of percentage changes of these parameters. The results of the systematic review were based on data from forty-six studies presented in nineteen articles. The addition of polyphenolic compounds to composite materials for bone regeneration improved the cytocompatibility and increased the activity of early markers of osteoblast differentiation, indicating a high osteoinductive potential of the materials. Polyphenolic compounds incorporated into the materials presumably give them high antioxidant properties and reduce the production of reactive oxygen species in macrophage cells, implying anti-inflammatory activity. The evidence was limited by the number of missing data and the heterogeneity of the data. 相似文献
68.
Iwona Radziejewska Katarzyna Supruniuk Micha Tomczyk Wiktoria Izdebska Magorzata Borzym-Kluczyk Anna Bielawska Krzysztof Bielawski Anna Galicka 《International journal of molecular sciences》2022,23(15)
Abnormal glycosylation of cancer cells is considered a key factor of carcinogenesis related to growth, proliferation, migration and invasion of tumor cells. Many plant-based polyphenolic compounds reveal potential anti-cancer properties effecting cellular signaling systems. Herein, we assessed the effects of phenolic acid, p-coumaric acid and flavonoids such as kaempferol, astragalin or tiliroside on expression of selected cancer-related glycoforms and enzymes involved in their formation in AGS gastric cancer cells. The cells were treated with 80 and 160 µM of the compounds. RT-PCR, Western blotting and ELISA tests were performed to determine the influence of polyphenolics on analyzed factors. All the examined compounds inhibited the expression of MUC1, ST6GalNAcT2 and FUT4 mRNAs. C1GalT1, St3Gal-IV and FUT4 proteins as well as MUC1 domain, Tn and sialyl T antigen detected in cell lysates were also lowered. Both concentrations of kaempferol, astragalin and tiliroside also suppressed ppGalNAcT2 and C1GalT1 mRNAs. MUC1 cytoplasmic domain, sialyl Tn, T antigens in cell lysates and sialyl T in culture medium were inhibited only by kaempferol and tiliroside. Nuclear factor NF-κB mRNA expression decreased after treatment with both concentrations of kaempferol, astragalin and tiliroside. NF-κB protein expression was inhibited by kaempferol and tiliroside. The results indicate the rationality of application of examined polyphenolics as potential preventive agents against gastric cancer development. 相似文献
69.
Verification of identity based on the analysis of dynamic signatures is an important problem of biometrics. The effectiveness of the verification significantly increases when the dynamic characteristics of signature (e.g. velocity of the pen) are considered. These characteristics are individual for each user and difficult to imitate. The effectiveness of the verification can be further improved by using partitioning. In this paper we propose a new method which uses partitioning. In our method partitions represent areas of high and low speed of signature and high and low pen?s pressure. All selected partitions are used by our algorithm, but more important in the classification process are these partitions, in which the signatures of the user acquired during training phase are more stable. Moreover, final classification is interpretable. In this paper we present the simulation results of the proposed method for the two databases: SVC2004 and BioSecure Database. 相似文献
70.