91 research outputs found

    The loss of MID in English

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    The thesis investigates the loss of MID in English through quantitative methods using historical corpus data. The research covers the period from the 10th century (the late Old English period) to the 14th century when MID became extinct in most Middle English literature. With the help of logistic regression analysis, the origin of the loss was identified in the 12th-century East Midlands due to the intense Anglo-Scandinavian contact. Language shift and dialect mixing may have occurred in the historical Anglo-Scandinavian community, leading to the semantic gain of WIÐ (originally an oppositional preposition) and a linguistic bias against MID. Detailed textual discussions of MID and WIÐ were made on the late Old English period and on each Middle English dialectal region. Multiple sociolinguistic factors such as immigrant society, the class of free peasantry, style and register concern are also involved in the historical change

    Changes in element accumulation, phenolic metabolism, and antioxidative enzyme activities in the red-skin roots of Panax ginseng

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    AbstractBackgroundRed-skin root disease has seriously decreased the quality and production of Panax ginseng (ginseng).MethodsTo explore the disease's origin, comparative analysis was performed in different parts of the plant, particularly the epidermis, cortex, and/or fibrous roots of 5-yr-old healthy and diseased red-skin ginseng. The inorganic element composition, phenolic compound concentration, reactive oxidation system, antioxidant concentrations such as ascorbate and glutathione, activities of enzymes related to phenolic metabolism and oxidation, and antioxidative system particularly the ascorbate–glutathione cycle were examined using conventional methods.ResultsAluminum (Al), iron (Fe), magnesium, and phosphorus were increased, whereas manganese was unchanged and calcium was decreased in the epidermis and fibrous root of red-skin ginseng, which also contained higher levels of phenolic compounds, higher activities of the phenolic compound-synthesizing enzyme phenylalanine ammonia-lyase and the phenolic compound oxidation-related enzymes guaiacol peroxidase and polyphenoloxidase. As the substrate of guaiacol peroxidase, higher levels of H2O2 and correspondingly higher activities of superoxide dismutase and catalase were found in red-skin ginseng. Increased levels of ascorbate and glutathione; increased activities of l-galactose 1-dehydrogenase, ascorbate peroxidase, ascorbic acid oxidase, and glutathione reductase; and lower activities of dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione peroxidase were found in red-skin ginseng. Glutathione-S-transferase activity remained constant.ConclusionHence, higher element accumulation, particularly Al and Fe, activated multiple enzymes related to accumulation of phenolic compounds and their oxidation. This might contribute to red-skin symptoms in ginseng. It is proposed that antioxidant and antioxidative enzymes, especially those involved in ascorbate–glutathione cycles, are activated to protect against phenolic compound oxidation

    Ionic Liquid-assisted Synthesis of Polyaniline/Gold Nanocomposite and Its Biocatalytic Application

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    In this report, a novel chemical synthesis of polyaniline/gold nanocomposite is explored using ionic liquid (IL) 1-Butyl-3-methylimidazolium hexafluorophosphate. The direct chemical synthesis of polyaniline/gold nanocomposite was initiated via the spontaneous oxidation of aniline by AuCl4−in IL. A nearly uniform dispersion of polyaniline/Au particles with a diameter of 450 ± 80 nm was produced by this method, which indicates that this method is more suitable for controlling particle dimensions. It was also found that the electrical conductivity of the polyaniline/gold nanocomposite was more than 100 times higher than that of the pure polyaniline nanoparticles. The polyaniline/gold nanocomposite displays superior function in the biocatalytic activation of microperoxidase-11 because of the high surface area of the assembly and the enhanced charge transport properties of the composite material. We also report the possible application of polyaniline/gold nanocomposite as a H2O2biosensor

    P. Gingivalis and E. Coli Lipopolysaccharides Exhibit Different Systemic but Similar Local Induction of Inflammatory Markers

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    Background Porphyromonas gingivalis is a gram-negative bacterium that is an important etiologic agent of human adult periodontitis. The goal of the study was to test the hypothesis that two different isoforms, PgLPS1435/1449 and PgLPS1690 exhibit differences in their capacity to stimulate systemic versus local responses compared to E. coli LPS. Methods Lipopolysaccharide (LPS) was inoculated into the scalp of mice and the response was measured locally at the site of site of inoculation and systemically in the heart/aorta. VCAM-1 was assessed at the protein level by ELISA and VCAM-1, E-selectin, and ICAM-1 at the RNA level of RNase protection assay. Serum TNF-α levels were also measured. Results E. coli LPS and both isoforms of P. gingivalis LPS groups were relatively potent in stimulating expression of inflammatory markers with E. coli LPS being somewhat more potent. In contrast, when the systemic response was measured in the heart/aorta, E. coli but not P. gingivalis LPS significantly induced inflammatory markers. At moderate to low doses (1 and 10 ug per injection) serum TNF–α levels were minimally induced by P. gingivalis LPS compared to E. coli LPS. Conclusion The results indicate that both forms of P. gingivalis LPS stimulate an inflammatory response when injected into connective tissue but are minimally stimulatory when a systemic response is measured. In contrast E. coli LPS is a potent stimulus at both the systemic and local level

    Cr3_3X4_4 (X=Se, Te) monolayers as new platform to realize robust spin filter, spin diode and spin valve

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    Two-dimensional ferromagnetic (FM) half-metals are promising candidates for advanced spintronic devices with small-size and high-capacity. Motivated by recent report on controlling synthesis of FM Cr3_3Te4_4 nanosheet, herein, to explore the potential application in spintronics, we designed spintronic devices based on Cr3_3X4_4 (X=Se, Te) monolayers and investigated their spin transport properties. We found that Cr3_3Te4_4 monolayer based device shows spin filtering and dual spin diode effect when applying bias voltage, while Cr3_3S4_4 monolayer is an excellent platform to realize a spin valve. The different transport properties are primarily ascribed to the semiconducting spin channel, which is close to and away from the Fermi level in Cr3_3Te4_4 and Cr3_3Se4_4 monolayers, respectively. Interestingly, the current in monolayer Cr3_3Se4_4 based device also displays a negative differential resistance effect (NDRE) and a high magnetoresistance ratio (up to 2*103^3). Moreover, we found thermally induced spin filtering effect and NDRE in Cr3_3Se4_4 junction when applying temperature gradient instead of bias voltage. These theoretical findings highlight the potential of Cr3_3X4_4 (X=Se, Te) monolayers in spintronic applications and put forward realistic materials to realize nanosale spintronic device

    Diabetes Enhances Periodontal Bone Loss Through Enhanced Resorption and Diminished Bone Formation

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    Using a ligature-induced model in type-2 Zucker diabetic fatty (ZDF) rat and normoglycemic littermates, we investigated whether diabetes primarily affects periodontitis by enhancing bone loss or by limiting osseous repair. Diabetes increased the intensity and duration of the inflammatory infiltrate (P \u3c 0.05). The formation of osteoclasts and percent eroded bone after 7 days of ligature placement was similar, while four days after removal of ligatures, the type 2 diabetic group had significantly higher osteoclast numbers and activity (P \u3c 0.05). The amount of new bone formation following resorption was 2.4- to 2.9-fold higher in normoglycemic vs. diabetic rats (P \u3c 0.05). Diabetes also increased apoptosis and decreased the number of bone-lining cells, osteoblasts, and periodontal ligament fibroblasts (P \u3c 0.05). Thus, diabetes caused a more persistent inflammatory response, greater loss of attachment and more alveolar bone resorption, and impaired new bone formation. The latter may be affected by increased apoptosis of bone-lining and PDL cells

    Advanced Glycation End Products Stimulate Osteoblast Apoptosis Via the MAP Kinase and Cytosolic Apoptotic Pathways

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    We have previously shown that diabetes significantly enhances apoptosis of osteoblastic cells in vivo and that the enhanced apoptosis contributes to diabetes impaired new bone formation. A potential mechanism is enhanced apoptosis stimulated by advanced glycation end products (AGEs). To investigate this further, an advanced glycation product, carboxymethyl lysine modified collagen (CML-collagen), was injected in vivo and stimulated a 5-fold increase in calvarial periosteal cell apoptosis compared to unmodified collagen. It also induced apoptosis in primary cultures of human or neonatal rat osteoblastic cells or MC3T3-E1 cells in vitro. Moreover, the apoptotic effect was largely mediated through RAGE receptor. CML-collagen increased p38 and JNK activity 3.2- and 4.4-fold, respectively. Inhibition of p38 and JNK reduced CML-collagen stimulated apoptosis by 45% and 59% and by 90% when used together (P \u3c 0.05). The predominant apoptotic pathway induced by CML-collagen involved caspase-8 activation of caspase-3 and was independent of NF-κB activation. When osteoblastic cells were exposed to a long-term low dose incubation with CML-collagen, there was a higher degree of apoptosis compared to short-term incubation. In more differentiated osteoblastic cultures, apoptosis was enhanced even further. These results indicate that advanced glycation end products, which accumulate in diabetic and aged individuals, may promote apoptosis of osteoblastic cells and contribute to deficient bone formation

    Optimization of Operating Parameters for Coal Low-Temperature Ashing: A Suitable and Efficient Treatment Method for Mineral Analysis in Coal

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    Low-temperature oxygen-plasma ashing plus X-ray diffraction analysis is one of the effective techniques to identify minerals in coal. However, previous publications have not provided any details of the exact low-temperature degrees and corresponding working conditions of ashers, and this could lead to two adverse effects without proper operating guidance: (1) a relatively high temperature (e.g., >150 °C) may cause alteration of minerals (particularly clay minerals), and (2) a relatively low temperature (e.g., (004) and kaolinite d(002) can be clearly distinguished by LTAs-XRD analysis. In addition, different low temperatures have certain influence on the crystal structure of minerals. When the power rises to above 300 W (about 150 °C), the crystal structure of minerals undergoes changes. The symmetry and integrity of the mineral peaks became worse, and destructive interference occurred between the spacing of reflection planes, resulting in significant decrease in diffraction peak intensity; thus, some trace minerals were unable to be identified. The study on the working parameters of the instrument would be helpful to ash coals more effectively and make qualitative and quantitative analysis of minerals more accurate

    The Behavior of gallium confined in carbon nanotubes during heating and cooling

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    The thermal expansion of gallium (Ga) encapsulated in carbon nanotubes has been studied. It is demonstrated that the volumetric expansion and contraction of the Ga confined in the carbon nanotubes display a linear relationship with temperature. While the level of the tip of the Ga column changes linearly with temperature, it returns to its previous position, without any hysteresis, when reheated or cooled to the original temperature, provided the Ga has not frozen and electron-beam irradiation is minimized. It is shown that electron beam irradiation can cause shrinkage in carbon-nanotube diameter, and that a high-intensity electron beam can also induce the formation of new carbon shells inside the carbon nanotubes. Upon freezing, the solid Ga has two unique orientation relationships with the carbon nanotubes.4 page(s
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