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Mn1−xZnxFe2O4 (x = 0.2-0.8) ferrite samples were successfully prepared by the sol-gel method. X-ray diffraction study reveals that single cubic spinel phase was formed in Mn1−xZnxFe2O4 samples. The SEM micrographs revealed that the microstructures change significantly with different Zn2+ doping concentration and sintering temperature while the grain size grow up to 9.48 μm for Mn0.6Zn0.4Fe2O4 sample sintered at 1100 °C. Further, the dielectric and magnetic measurements indicated that both Zn2+ doping and sintering temperature could affect both electrical and magnetic parameters such as dielectric constant and saturation magnetization in a great manner. The Mn0.6Zn0.4Fe2O4 sample sintered at 1100 °C for 8 h is found to show the largest Ms value (77.30 emu/g) in this work. These results indicate that Zn2+ doping or sintering temperature can adjust the microstructures, dielectric and magnetic properties of Mn1−xZnxFe2O4 ferrites. [ABSTRACT FROM AUTHOR]

Different strategies are increasingly used for early intervention in prediabetes in China, but the effects of these strategies on incident diabetes have not yet been confirmed. The aim of the present study was to assess systematically the effects of different strategies for preventing diabetes, aimed at Chinese people with prediabetes. Seven electronic databases were searched to identify eligible trials published from inception to September 20, 2016. Randomized controlled trials with a minimum follow‐up duration of 6 months were included. Standard pairwise meta‐analysis with a random‐effects model and network meta‐analysis with a frequentist framework were performed. A total of 63 studies, including 11 intervention strategies, were included. Compared with placebo, all strategies, except for lipid‐affecting drugs and sitagliptin, reduced the rate of incident diabetes with different levels of effectiveness, ranging from 0.18 (95% confidence interval [CI] 0.12, 0.27) to 0.39 (95% CI 0.20, 0.75). Ranking probability analysis indicated that metformin and β‐cell‐stimulating drugs reduced the risk of diabetes most, with probabilities of 87.4% and 81%, respectively. Ethnicity and cultural factors should be considered for diabetes prevention. Most of the included trials were of poor methodological quality, however, and the results should be interpreted with caution. [ABSTRACT FROM AUTHOR]

The scaffold which provides space for cell growth, proliferation, and differentiation, is a key factor in bone tissue engineering. However, improvements in scaffold design are needed to precisely match the irregular boundaries of bone defects as well as facilitate clinical application. In this study, controllable three-dimensional (3D) porous shape memory polyurethane/nano-hydroxyapatite (SMPU/nHAP) composite scaffold was successfully fabricated for bone defect reparation. Detailed studies were performed to evaluate its structure, apparent density, porosity, and mechanical properties, emphasizing the contribution of nHAP particles on shape recovery behaviors and biological performance in vitro. The effect of nHAP particles in porous SMPU/nHAP composite scaffold was found to enhance the compression resistance by 37%, shorten the compression recovery time by 41%, reduce the tensile resistance by 78%, reach the shape recovery ratio of 99%, and promote the cell proliferation by 13% after 7 days of culture. These results revealed that the 3D structure and aperture of as-prepared scaffold were controllable. And in minimally invasive surgery and bone repair surgery, this porous composite scaffold could significantly reduce the operative time and promote the bone cell growth. Therefore, this porous SMPU/nHAP composite scaffold design has potential applications for the bone tissue engineering. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 244-254, 2018. [ABSTRACT FROM AUTHOR]

Background: Diabetic distal symmetric polyneuropathy (DSPN) is one of the most common microvascular complications of diabetes mellitus, and it has become a major public health problem worldwide because of its high and increasing prevalence, morbidity, and disability rate. The current medications for DSPN are not entirely satisfactory. Preliminary studies indicated that the Chinese herbal TangBi Formula may alleviate signs and symptoms and improve the velocity of nerve conduction in patients with DSPN. This study was designed to determine if Chinese herbal medicine used in combination with conventional treatment is more effective than conventional treatment alone.Methods/design: We are conducting a multicenter, placebo-controlled, double-blind, randomized, controlled clinical trial as a means of assessing the therapeutic effects of traditional Chinese medicine (TCM) treatment. A total of 188 patients will be randomized in a 1:1 ratio to a treatment group (TangBi Formula plus mecobalamin) and a control group (placebo plus mecobalamin). The test period lasts 6 months, during which all of the patients will be given standard medical care as recommended by established guidelines. The primary outcome will be development of differences in changes in clinical symptoms and signs in patients and changes in Michigan Diabetic Neuropathy Score (MDNS) between the two groups before and after treatment. The secondary outcome will be changes in nerve conduction velocity and in single clinical signs and symptoms. Safety assessments and adverse events will also be evaluated.Discussion: We postulate that patients with DSPN will benefit from therapy that includes TCM. If successful, this work will provide an evidence-based complementary therapeutic approach for treatment of DSPN.Trial Registration: ClinicalTrials.gov, NCT03010241 . Registered on 2 January 2017. [ABSTRACT FROM AUTHOR]

La 1− x Sm x − y Sr y CoO 3−δ (LSSC; x = 0.475, 0.650, 0.825, y = 0.35, 0.40, 0.45) compounds, which have the same compositions as the La 0.7 Sr 0.3 CoO 3−δ (LSC) and Sm 0.5 Sr 0.5 CoO 3−δ (SSC) mixture (corresponding mole ratio is 3:1, 1:1 and 1:3, respectively), are synthesized through a conventional solid-state reaction and characterized by X-ray diffraction, thermal expansion coefficient, X-ray photoelectron spectrometer and electrical conductivity measurement, as well as the electrochemical impedance spectra and single cell performance measurement. Interestingly, the experimental results reveal that with the linear increase of y in LSSC, the conductivity of the corresponding samples does not alter linearly but reaches a peak when y = 0.35, namely, the maximum electrical conductivity enhancing from 2148 S cm −1 (LSC, y = 0.30) and 1802 S cm −1 (SSC, y = 0.50) to 2750 S cm −1 ( y = 0.35). In addition, this turning point coincidently corresponds to the structure transition from hexagonal ( y = 0.35) to orthorhombic ( y = 0.40). Furthermore, comparing with LSC and SSC, the cathode polarization resistance (R P ) decreases by about 50% and 38%, respectively, after employing the LSSC ( y = 0.40) compound as cathode at 800 °C and 0.21 atm p(O 2 ), which also leads to an increment of 49% and 31% respectively in peak power density. These results imply promising applications of such effective cathodes for intermediate temperature solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

A new design of cathode current-collecting element (CCCE) based on SmSrCoO, which contains gas channels and an array of truncated-pyramid-shaped contact tips, is synthesized through die pressing followed by a conventional solid-state reaction for intermediate-temperature solid oxide fuel cells (IT-SOFCs). This configuration could not only maintain the high electronic conductivity of the material to ensure the efficiency of current collecting, but also improve the gas diffusion rate at the cathode side. The height h of the channel tips on the CCCEs reaches approximately 60, 120, and 240 μm, respectively, which results in the variation in polarization resistance ( R ) more significantly than the contact area of the tips does. The experiments show that the R of the symmetric cells decreased from 0.267 to 0.060 Ω cm at 800 °C after employing the CCCE with modified parameters. In addition, the measured peak power density of the individual cell is enhanced from 111 to 145 mW cm at 800 °C. The results show that the cathode current-collecting elements may be potentially useful for applications in IT-SOFCs. [ABSTRACT FROM AUTHOR]

Barium titanate (BT) nanoparticles were fabricated using sol-gel method, and then immobilized onto the surface of carbon nanotubes (CNTs) to fabricate heterogeneous barium titanate@carbon nanotube (BT@CNT) nanocomposites. The electromagnetic (EM) wave absorption ability increased as the weight fraction of BT@CNT increased. The BT@CNT 30 wt.% nanocomposites with thickness of 1.1 mm showed a minimum reflection loss (R.L.) of ∼ − 37.2 dB (> 99.98% absorption) at 13.9 GHz with a response bandwidth of 1.6 GHz (12.3 ∼ 13.9 GHz), and were the best absorber when compared to similar nanocomposites with different thicknesses. The relationship between conductivity and EM wave absorption properties was also discussed. Appropriate conductivity also plays an important role to obtain optimum absorption performance. BT@CNT nanocomposites exhibited significant absorption ability, and this indicates that they can be utilized as an effective EM wave absorber material. Left: absorption performance and response bandwidth of BT@CNT 30 wt.% nanocomposites with various thicknesses. Right: TEM image of BT@CNT. [ABSTRACT FROM AUTHOR]

When ultrasonic waves propagate in composite materials, the propagation behaviors result from the combination effects of various factors, such as material anisotropy and viscoelastic property, internal microstructure and defects, incident wave characteristics and interface condition between composite components. It is essential to make it clear how these factors affect the ultrasonic wave propagation and attenuation characteristics, and how they mutually interact on each other. In the present paper, based on a newly developed time-domain finite element analysis code, PZflex, a unique approach for clarifying the detailed influence mechanism of aforementioned factors is proposed, in which each attenuation component can be extracted from the overall attenuation and analyzed respectively. By taking into consideration the interrelation between each individual attenuation component, the variation behaviors of each component and internal dynamic stress distribution against material anisotropy and matrix viscosity are separately and quantitatively evaluated. From the detailed analysis results of each attenuation component, the energy dissipation at interface is a major component in ultrasonic wave attenuation characteristics, which can provide a maximum contribution rate of 68.2 % to the overall attenuation, and each attenuation component is closely related to the material anisotropy and viscoelasticity. The results clarify the correlation between ultrasonic wave propagation characteristics and material viscoelastic properties, which will be useful in the further development of ultrasonic technology in defect detection. [ABSTRACT FROM AUTHOR]