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1.
Chemical and structural properties of the system (1–x)Fe2O3 + xNd2O3, 0x1, were investigated using X-ray diffraction, 57Fe Mössbauer spectroscopy and Fourier transform-infrared (FT-IR) spectroscopy. The samples were prepared by the chemical coprecipitation and thermal treatment of Fe(OH)3/Nd(OH)3 coprecipitates. X-ray diffraction showed the presence of oxide phases -Fe2O3 + NdFeO3 in the Fe2O3-rich region, and the oxide phases Nd2O3 + NdFeO3 in the Nd2O3-rich region. 57Fe Mössbauer spectra were characterized with one sextet of spectral lines at room temperature. Mathematical evaluation of the Mössbauer spectra showed distinct regularities in the changes of Mössbauer parameters, thus indicating the presence of two subspectra with very similar spectral behaviour. High sensitivity of the Nd2O3 phase to the moisture and atmosphere CO2 was demonstrated by FT-IR spectroscopy. 相似文献
2.
Hyun-Ah Shin Mira Park Jasvinder Paul Banga Helen Lew 《International journal of molecular sciences》2022,23(10)
Orbital fibroblasts (OFs) in thyroid-associated ophthalmopathy (TAO) are differentiated from pre-adipocytes and mature adipocytes; increased lipid and fat expansion are the major characteristics of ophthalmic manifestations. Human placental mesenchymal stem cells (hPMSCs) were reported to immunomodulate pathogenesis and suppress adipogenesis in TAO OFs. Here, we prepared transforming growth factor β (TGFβ, 20 ng/mL)-treated hPMSCs (TGFβ-hPMSCs) in order to enhance anti-adipogenic effects in vitro and in TAO mice. TAO OFs were grown in a differentiation medium and then co-cultured with hPMSCs or TGFβ-hPMSCs. TAO OFs were analyzed via quantitative real-time polymerase chain reaction, Oil red O staining, and western blotting. The results showed that TGFβ-hPMSCs reduced the expression of adipogenic, lipogenic, and fibrotic genes better than hPMSCs in TAO OFs. Moreover, the adipose area decreased more in TAO mice injected with TGFβ-hPMSCs compared to those injected with hPMSCs or a steroid. Further, TGFβ-hPMSCs inhibited inflammation as effectively as a steroid. In conclusion, TGFβ-hPMSCs suppressed adipogenesis and lipogenesis in vitro and in TAO mice, and the effects were mediated by the SMAD 2/3 pathways. Furthermore, TGFβ-hPMSCs exhibited anti-inflammatory and anti-fibrotic functions, which suggests that they could be a new and safe method to promote the anti-adipogenic function of hPMSCs to treat TAO patients. 相似文献
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A bottom-up method for creating a hierarchy of entity-relationship diagrams (HERD) from a given, flat ER diagram (ERD) is proposed. The hierarchy consists of simple and interrelated diagrams—ER structures—with external relationships to other structures. The HERD-tree diagram, which provides the most general view of the conceptual schema, is located at the top of the hierarchy. The method is based on packaging operations, which group entities and relationships according to certain criteria. These operations are applied in several steps on a given (presumably large-scale) ERD. We describe the new constructs, which are added to the ER model to enable the creation of HERD, and a bottom-up method for creating HERD. We also evaluate HERD from the point of view of user comprehension and preference, based on an experimental comparison to flat ERDs.
相似文献
Peretz ShovalEmail: |
4.
The purpose of this paper is to present an algorithm developed for real-time estimation of skeletal muscle ischemia, based on parameters extracted from in vivo obtained electrical impedance spectra. A custom impedance spectrometer was used to acquire data sets: complex impedance spectra measured at 27 frequencies in the range of 100 Hz-1 MHz, and tissue pH. Twenty-nine in vivo animal studies on rabbit anterior tibialis muscle were performed to gather data on the behavior of tissue impedance during ischemia. An artificial neural network (ANN) was used to quantitatively describe the relationship between the parameters of complex tissue impedance spectra and tissue ischemia via pH. The ANN was trained on 1249, and tested on 946 ischemic tissue impedance data sets. A correlation of 94.5% and a standard deviation of 0.15 pH units was achieved between the ANN estimated pH and measured tissue pH values. 相似文献
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This article introduces a high-level system using belief functions for exchanging and managing imperfect information about events on the road in vehicular ad hoc networks. The main purpose of this application is to provide the most reliable information for the driver from multiple messages received informing the driver about events on the roads. This system and some variants are tested using a MATLAB? simulator. An implementation with Android smartphones using a Bluetooth technology to exchange the messages is also introduced. 相似文献
7.
Sergio Scudino Kumar Babu Surreddi Mohsen Samadi Khoshkhoo Mira Sakaliyska Gang Wang Jürgen Eckert 《Advanced Engineering Materials》2010,12(11):1123-1126
In this work, the effect of channel‐die compression (CDC) on the mechanical behavior of the Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass is analyzed. The results indicate that CDC can be successfully used as a pre‐deformation process to effectively enhance the room temperature plastic strain ability of metallic glasses. The origin of the improved mechanical properties is most likely due to the creation during CDC of a heterogenous microstructure consisting of hard and soft regions able to hinder the rapid propagation of shear bands. 相似文献
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Sulfur dioxide SO? is the key additive for the preservation of wines. Carbonyl and keto compounds in wine can bind to SO? and decrease its efficacy, resulting in higher total SO? requirements. Increased consumer demand for low sulfite and organic wines pose production challenges if SO? binders have not been properly managed during vinification. Malolactic fermentation (MLF) has been known to reduce bound SO? levels but detailed time course studies are not available. In this work, the kinetics of major SO? binding compounds and malic acid were followed during MLF in wine with 12 commercially available strains of Oenococcus oeni. Pyruvic acid, acetaldehyde and α-ketoglutaric acid were degraded to various degrees by O. oeni, but galacturonic acid was not. At the time of malic acid depletion, percent degradation of pyruvate, α-ketoglutaric acid and acetaldehyde was 49%, 14% and 30%, respectively. During MLF, the decrease in average bound SO? levels, as calculated from carbonyl metabolism, was 22%. The largest reduction in wine carbonyl content occurred in the week after completion of MLF and was 53% (107 mg/L to 34 mg/L) calculated as bound SO?. Prolonged activity of bacteria in the wines (up to 3 weeks post malic acid depletion) resulted only in reduced additional reductions in bound SO? levels. The results suggest that microbiological wine stabilization one week after malic acid depletion is an effective strategy for maximum removal of SO? binders while reducing the risk of possible post-ML spoilage by O. oeni leading to the production acetic acid and biogenic amines. 相似文献