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1.
Harizi Riadh Walha Rim Drira Fadoua Zaied Mourad 《Multimedia Tools and Applications》2022,81(3):3091-3106
Multimedia Tools and Applications - Text recognition in the wild is a challenging task in the field of computer vision and machine learning. Existing optical character recognition engines cannot... 相似文献
2.
Kyuri Kim Young Seung Lee Nam Kim Hyung-Do Choi Dong-Jun Kang Hak Rim Kim Kyung-Min Lim 《International journal of molecular sciences》2021,22(1)
With the rapid growth of wireless communication devices, the influences of electromagnetic fields (EMF) on human health are gathering increasing attention. Since the skin is the largest organ of the body and is located at the outermost layer, it is considered a major target for the health effects of EMF. Skin pigmentation represents one of the most frequent symptoms caused by various non-ionizing radiations, including ultraviolet radiation, blue light, infrared, and extremely low frequency (ELF). Here, we investigated the effects of EMFs with long-term evolution (LTE, 1.762 GHz) and 5G (28 GHz) bandwidth on skin pigmentation in vitro. Murine and Human melanoma cells (B16F10 and MNT-1) were exposed to either LTE or 5G for 4 h per day, which is considered the upper bound of average smartphone use time. It was shown that neither LTE nor 5G exposure induced significant effects on cell viability or pigmentation. The dendrites of MNT-1 were neither lengthened nor regressed after EMF exposure. Skin pigmentation effects of EMFs were further examined in the human keratinocyte cell line (MNT-1-HaCaT) co-culture system, which confirmed the absence of significant hyper-pigmentation effects of LTE and 5G EMFs. Lastly, MelanoDerm™, a 3D pigmented human epidermis model, was irradiated with LTE (1.762 GHz) or 5G (28 GHz), and image analysis and special staining were performed. No changes in the brightness of MelanoDerm™ tissues were observed in LTE- or 5G-exposed tissues, except for only minimal changes in the size of melanocytes. Collectively, these results imply that exposure to LTE and 5G EMFs may not affect melanin synthesis or skin pigmentation under normal smartphone use condition. 相似文献
3.
Daniel Drdlik Martin Slama Hynek Hadraba Katarina Drdlikova Jaroslav Cihlar 《Ceramics International》2018,44(3):2884-2891
In the present work, the preparation of sintered lithium-doped tricalcium phosphates was studied, along with their physical, mechanical, and biological properties. Calcium phosphates were shaped via the use of electrophoretic deposition (EPD), using colloidally milled dispersions of hydroxyapatite (HAp) particles. The dispersions were stabilised with monochloroacetic acid. Lithium was incorporated into the structure via an addition of lithium chloride, which also served to optimise the deposition process. The dispersions were milled colloidally for periods of 0–48 h. The colloidal milling resulted in two effects: i) disintegration of the commercial HAp powder (10 µm) agglomerates, ii) unimodal distribution of the HAp particles (~ 170 nm). The fine particles of the milled HAp dispersions accelerated the deposition rate, and increased the mass of the deposit. The reduced size of the initial particles, owed to the milling, led to the superior arrangement of the particles during deposition and to reduced porosity after sintering (1050–1250 °C). The HAp decomposed into tricalcium phosphate phases during sintering. At a sintering temperature of 1250 °C, grain growth occurred, which consequently resulted in a slight degradation of the mechanical properties (reduction in hardness and Young's modulus). In contrast, the hardness and Young's modulus increased as the dispersion milling time increased (smaller grain size after sintering); however, the fracture toughness did not change. The results of the biological testing confirmed the bioactivity of the material through the growth of the apatite layer in the simulated body fluid (SBF), and the biodegradation of the prepared materials in the Tris-HCl solution. With regard to the preparation of compact lithium-doped tricalcium phosphates, the best results were obtained in the case of the sample that utilised the dispersion that was milled for 48 h, and was sintered at 1050 °C. 相似文献
4.
Rim Ben Abdallah Ana Belén Bautista-Ortin Tesnime Ghazouani Wafa Talbi Maria D. Jiménez-Martinez Encarna Gómez-Plaza Sami Fattouch 《International Journal of Food Science & Technology》2019,54(5):1633-1641
During technological processing, proanthocyanidins and anthocyanidins could be partly lost due to the complexation phenomena, affecting food and beverage nutritional properties, organoleptic properties and health-promoting potentials. A common issue is encountered when processing food and beverage which is binding of phenolics to dietary proteins. The present investigation aims at evaluating the proteolysis contribution, using pure protease (Pepsin, 3000 units g−1), to protein–anthocyanidin and protein–proanthocyanidin interactions. Bovine serum albumin (BSA), ovalbumin (OVA) and casein (CAS) dietary protein models were used. High-performance liquid chromatography coupled to diode array detector (HPLC-DAD) and size exclusion chromatography analyses proved that pepsin treatment significantly (P > 0.05) decreased the ratio of flavonoids’ interaction with tested proteins . The proteolysis reduced anthocyanidin interactions with CAS, OVA and BSA by 64.88%, 57.37% and 42.87% respectively. Similarly, proanthocyanidins interaction with CAS, OVA and BSA were reduced by 34.23%, 13.74% and 2.39% respectively. This study provides the basis to develop innovative technologies to limit protein–flavonoid complexation during food and beverage processing. 相似文献
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Organic Electronics: Self‐Assembled,Millimeter‐Sized TIPS‐Pentacene Spherulites Grown on Partially Crosslinked Polymer Gate Dielectric (Adv. Funct. Mater. 24/2015) 下载免费PDF全文
Hocheon Yoo Hyun Ho Choi Tae Joo Shin Taiuk Rim Kilwon Cho Sungjune Jung Jae‐Joon Kim 《Advanced functional materials》2015,25(24):3795-3795
9.
Katarina Drdlikova Karel Maca Martin Slama Daniel Drdlik 《Journal of the American Ceramic Society》2019,102(12):7137-7144
The study is focused on an optimization of the slip-casting process used for the fabrication of the transparent/translucent alumina ceramics; more precisely, on specifying the most appropriate way to stabilize the cast alumina suspensions. An innovative method of the particles’ stabilization by plasma treatment was compared with the classical electrostatic and the most frequently used electrosteric approach. Properties of green bodies (pore size distribution, density) and sintered samples (density, mean grain size, real in-line transmittance) were measured in term to evaluate the impact of the individual stabilization mechanism on the final properties of the transparent/translucent ceramics. The results showed that all tested approaches enable the preparation of the transparent/translucent alumina ceramics by Hot Isostatic Pressing. Ceramics prepared from the plasma treated as well as the electrostatically stabilized powders exhibited narrower pore size distribution, higher density, and lower mean grain size in comparison to ceramics fabricated from only electrosterically stabilized powders. Despite these promising properties the plasma-treated samples resulted in an unexpectedly low RIT of 36% caused by the presence of thin cracks. However, the electrostatically stabilized samples achieved the highest RIT value of 57%. 相似文献
10.
Ana Belén Bautista-Ortín Rim Ben Abdallah Liliana del Rocío Castro-López María Dolores Jiménez-Martínez Encarna Gómez-Plaza 《International journal of molecular sciences》2016,17(1)
The transference and reactivity of proanthocyanidins is an important issue that affects the technological processing of some fruits, such as grapes and apples. These processes are affected by proanthocyanidins bound to cell wall polysaccharides, which are present in high concentrations during the processing of the fruits. Therefore, the effective extraction of proanthocyanidins from fruits to their juices or derived products will depend on the ability to manage these associations, and, in this respect, enzymes that degrade these polysaccharides could play an important role. The main objective of this work was to test the role of pure hydrolytic enzymes (polygalacturonase and cellulose) and a commercial enzyme containing these two activities on the extent of proanthocyanidin-cell wall interactions. The results showed that the modification promoted by enzymes reduced the amount of proanthocyanidins adsorbed to cell walls since they contributed to the degradation and release of the cell wall polysaccharides, which diffused into the model solution. Some of these released polysaccharides also presented some reactivity towards the proanthocyanidins present in a model solution. 相似文献