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Solid oxide fuel cells (SOFCs) have been regarded as promising eco-friendly power sources in recent years owing to their high energy conversion efficiency and fuel flexibility. La2Mo2O9-based ceramics draw researchers’ attention due to their good performance as electrolyte materials for SOFCs. In this study, the Sm and Al co-doped La2Mo2O9, La2-xSmxMo1.8Al0.2O8.7 (x=0.1,0.2,0.3 and 04, LSMAO), are successfully synthesized by the sol-gel method as electrolyte materials for SOFCs. The phase evolution, sintering, the microstructural and electrochemical performance of LSMAO were observed by TG-DSC, XRD, SEM, and impedance analyses, respectively. The results show that the highly phase-pure cubic LSMAO nanopowders can be obtained after calcining at 600 °C for 2 h. The as-synthesized LSMAO powders exhibited a better sintering activity. All these samples were found to have a relative density above 94.5% after sintering at 950 °C for 5 h. The electrical performance study shows that higher doping concentrations of Sm caused a decrease in ionic conductivity and an increase in activation energy. La1.9Sm0.1Mo1.8Al0.2O8.7 exhibited the highest oxide ionic conductivity (σ800 °C=0.033 S/cm) and lowest electrical activation energy (Ea=0.85 eV). This shows that LSMAO could be used as a potential electrolyte for intermediate temperature SOFCs (IT-SOFCs).

In our project, we sequenced 6 adult mice heart samples on Illumina HiSeq Platform in total and generated about 5.65 Gb per sample.Among them, 3 samples were in the Ctrl group and 3 samples were in the KLF7 cardiomyocyte-specific knockout group.

We determined the contents of central carbon energy metabolites and medium and long-chain free fatty acids in the heart tissue of adult mice with cardiomyocyte-specific knockout KLF7 and young mice (infants)with cardiomyocytw-specific overexpression of KLF7.

Reliability assessment is a widely-used tool to evaluate the performance of civil structures during their service lives. It provides a quantitative measure of structural safety level under a probabilistic framework, taking into account the uncertainties associated with structural resistance and the external load actions. The structural resistance (e.g., strength and stiffness) may deteriorate with time due to the impacts of environmental or operating factors. Moreover, the external load effects are often non-stationary on the temporal scale with time-variant characteristics in terms of occurrence rate and/or intensity. Under this context, the structural reliability would be dependent on the duration of the reference period of interest, known as time-dependent reliability. The characteristics of the random quantities can be described by probability distribution models, which can be calibrated through experimental or in-situ data. In cases where available data are limited (e.g., those regarding the deterioration process of structural resistance), some techniques such as the probability-bounding approach can be used to handle the imprecise variables. This chapter discusses the time-dependent reliability of aging structures subjected to imprecise deterioration information. First, the analytical methods for structural time-dependent reliability are introduced. Subsequently, a reliability-bounding approach is discussed, followed by two numerical examples to demonstrate the applicability of the reliability assessment methods.

We report the superconductivity of a new quaternary compound ThMo$_2$Si$_2$C, synthesized with the arc-melting technique. The compound crystallizes in a tetragonal CeCr$_2$Si$_2$C-type structure with cell parameters of $a$ = 4.2296 \r{A}and $c$ = 5.3571 \r{A}. An interlayer Si-Si covalent bonding is suggested by the atomic distance. The electrical resistivity and magnetic susceptibility measurements indicate a Pauli-paramagnetic metal with dominant electron-electron scattering in the normal-state. Bulk superconductivity at 2.2 K is demonstrated with a dimensionless specific-heat jump of ${\Delta}C/\gamma_{\rm n}T$ = 0.98. The superconducting parameters of the critical magnetic fields, coherence length, penetration depth, and superconducting energy gap are given., Comment: 14 pages, 6 figures, 3 tables. Accepted for publication in SCIENCE CHINA Physics, Mechanics & Astronomy

This study aimed to construct a widely accepted prognostic nomogram in Chinese high-grade osteosarcoma (HOS) patients aged ≤ 30 years to provide insight into predicting 5-year overall survival (OS). Data from 503 consecutive HOS patients at our centre between 12/2012 and 05/2019 were retrospectively collected. Eighty-four clinical features and routine laboratory haematological and biochemical testing indicators of each patient at the time of diagnosis were collected. A prognostic nomogram model for predicting OS was constructed based on the Cox proportional hazards model. The performance was assessed by the concordance index (C-index), receiver operating characteristic curve and calibration curve. The utility was evaluated by decision curve analysis. The 5-year OS was 52.1% and 2.6% for the nonmetastatic and metastatic patients, respectively. The nomogram included nine important variables based on a multivariate analysis: tumour stage, surgical type, metastasis, preoperative neoadjuvant chemotherapy cycle, postoperative metastasis time, mean corpuscular volume, tumour-specific growth factor, gamma-glutamyl transferase and creatinine. The calibration curve showed that the nomogram was able to predict 5-year OS accurately. The C-index of the nomogram for OS prediction was 0.795 (range, 0.703–0.887). Moreover, the decision curve analysis curve also demonstrated the clinical benefit of this model. The nomogram provides an individualized risk estimate of the 5-year OS in patients with HOS aged ≤ 30 years in a Chinese population-based cohort.

Elastic cables have the advantages of desirable seismic mitigation effect, low cost, and convenient installation, and have been used widely in low-to-mid-span bridges. However, their utiliz...

We collected in situ high-temperature powder X-ray diffraction (XRD) patterns, as well as Raman and Fourier transform infrared (FTIR) spectra on a natural serandite sample. The volumetric thermal expansion coefficient αV (K−1) is determined as a linear function of T (K): 37.6(5) × 10−9 × T + 11.1(3) × 10−6, with an averaged value of 31.7(10) × 10−6 K−1, while the anisotropy of axial thermal expansivities shows the order of αa > αb > αc. The isobaric Gruneisen parameters γiP are constrained as: 0.2–1.6 for most of the lattice vibrations below 500 cm−1; while 0–0.6 for the O–Si–O bending and Si–O stretching modes inside the Si3O9 chains above 500 cm−1. As compared with common silicate phases in the upper mantle and the transition zone, the γiP parameters for the internal vibrations are significantly smaller in silicate chains (serandite, enstatite) than those in Si2O7 groups (wadsleyite) and isolated SiO4 units (forsterite, pyrope), since the rotation of the bridging O atoms (in the direction perpendicular to Si–O–Si) could relax the SiO4 tetrahedra at elevated temperature. The OH-bending vibration of serandite is observed in both Raman-active (1378 cm−1) and IR-active (1389 cm−1) modes, with a temperature-dependence of − 0.07 and − 0.09 cm−1/K, respectively. The red-shift of these OH-bending modes with increasing temperature indicates that the hydrogen bond gets weaker as the O3…O4 distance becomes larger during thermal expansion. Additionally, our polarized FTIR spectra confirm that the stretching mode of the very strong hydrogen bond, a broad absorption region (1400–3300 cm−1), is polarized in the direction of E//b, as reported by Hammer et al. (Am Mineral 83:569–576, 1998).

The effect of powder characteristics on the thermal conductivity and mechanical properties of silicon nitride (Si 3 N 4 ) ceramics were investigated systematically by using two α-Si 3 N 4 powders a ...

The environmental or anthropogenic factors, to which the in-service bridges are subjected, are responsible for the reduction of bridge performance, and finally lead to great service risk for bridges and increase the probability of substantial economic losses. Probability-based estimate of bridge resistance is an essential indicator for the bridge condition evaluation and for optimization of bridge maintenance/repair decisions. It places an emphasis on the proper probabilistic models of structural properties and assessment methods. Making full use of historical service load information may improve the accuracy of bridge performance assessment with reduced epistemic uncertainty for existing aging bridges. In to-date analyses to update the bridge resistance with past service information, the models of resistance deterioration have been assumed as either deterministic or fully correlated, which may differ significantly from the realistic case. With this regard, this paper proposes a novel method for updating the resistance of service-proven bridges with a realistic deterioration model. The Gamma stochastic process has been suggested in the literature to describe the probabilistic behavior of structural time-dependent resistance and thus is adopted in this paper. An illustrative bridge is presented to demonstrate the applicability of the proposed method. Parametric examples are conducted to investigate the role of resistance deterioration model in the updated estimate of bridge resistance with historical service information. Keywords: Existing aging bridges, Historical load information, Resistance updating, Gamma deterioration process, Bridge safety

Miniaturization is a trend of development toward practical applications for diamond nitrogen-vacancy centers-based sensors. We demonstrate a compact diamond magnetic field sensor device using a standard microfabrication process. A single-crystal-diamond plate is embedded in a cavity formed with stacking of three silicon chips. Thermal compression bonding is implemented at silicon–silicon and diamond–silicon interfaces ensuring mechanical robustness. The specific construction volume for the essential sensor component is about 10 × 10 × 1.5 mm3. By integrating a gradient index lens pigtailed fiber to the sensor device, 532-nm laser light and emitted fluorescence share a common path for excitation and detection. An omega-shaped transmission line for applied microwave power is fabricated directly on the surface of diamond. The integrated sensor device exhibits an optimized sensitivity of 2.03 nT·Hz−1/2 and over twofold enhancement of fluorescence collection efficiency compared to bare diamond. Such a sensor is utilized to measure a magnetic field change caused by switching a household electrical appliance.

Electric power systems play a critical role in assuring modern society’s functionalities. Earthquakes are one of the most destructive natural hazards that affect the serviceability of electricity t...

Probability-based seismic performance assessment of in-service bridges has gained much attention in the scientific community during the past decades. The nonlinear static pushover analysis is critical for describing the seismic behaviour of bridges subjected to moderate to high seismicity due to its simplicity. However, in existing analysis methods, the generation of pushover curve needs tremendous amount of computational costs and requires skills, which may halter its application in practice, implying the importance of developing practice-oriented analysis method with improved efficiency. Moreover, the bridge pier performance has been modelled as deterministic, indicating that the variation associated with the pier material and mechanical properties remains unaddressed. The correlation in the performance of different piers also exists due to the common design provisions and construction conditions but has neither been taken into account. This paper develops a simplified pushover analysis procedure for the seismic assessment of simply supported RC bridges. With the proposed method, the pushover curve of the bridge can be obtained explicitly without complex finite element modelling. A random factor is introduced to reflect the uncertainty in relation to the pushover curve. The correlation in the pier performance is considered by employing the Gaussian copula function to construct the joint probability distribution. Illustrative examples are presented to demonstrate the applicability of the method and to investigate the impact of variation and correlation in bridge pier behaviour on the seismic performance assessment. Keywords: Seismic assessment, Simply supported RC bridge, Nonlinear analysis, Simplified method, Variation in pier behaviour, Correlation in pier behaviour

In probabilistic analyses and structural reliability assessments, it is often difficult or infeasible to reliably identify the proper probabilistic models for the uncertain variables due to limited supporting databases, e.g., limited observed samples or physics-based inference. To address this difficulty, a probability-bounding approach can be utilized to model such imprecise probabilistic information, i.e., considering the bounds of the (unknown) distribution function rather than postulating a single, precisely specified distribution function. Consequently, one can only estimate the bounds of the structural reliability instead of a point estimate. Current simulation technologies, however, sacrifice precision of the bound estimate in return for numerical efficiency through numerical simplifications. Hence, they produce overly conservative results in many practical cases. This paper proposes a linear programming-based method to perform reliability assessments subjected to imprecisely known random variables. The method computes the tight bounds of structural failure probability directly without the need of constructing the probability bounds of the input random variables. The method can further be used to construct the best-possible bounds for the distribution function of a random variable with incomplete statistical information.

Background Cardiac hypertrophy is a serious factor underlying heart failure. Although a large number of pathogenic genes have been identified, the underlying molecular mechanisms of cardiac hypertrophy are still poorly understood. MicroRNAs are a class of small non-coding RNAs which regulate their target genes at the post-transcriptional level. L-type calcium channels play important role in hypertrophic signaling pathways, and CACNA1C is encoded by L-type calcium channels. Here, we hypothesize that the overexpression of miR-135b can attenuate hypertrophy by targeting CACNA1C. Methods We test the functional involvement of miR-135b in cardiac hypertrophy model. In order to evaluate the effect of miR-135b in cardiac hypertrophy, miR-135b mimic, miR-135b agomir and α-MHC-miR-135b transgenic mice were used for the overexpression of miR-135b. Luciferase reporter assays were used to testify the binding of miR-135b to the CACNA1C 3′UTR. Results Our results revealed that in a pathological cardiac hypertrophy model, the expression of miR-135b was clearly downregulated. Hypertrophic marker genes were upregulated after the knockdown of miR-135b in vitro, while the overexpression of miR-135b attenuated hypertrophy. These results suggested that miR-135b may weaken hypertrophic signals. We then explored the mechanism of miR-135b in hypertrophy and identified that CACNA1C was a target gene for miR-135b. The overexpression of miR-135b attenuated cardiac hypertrophy by targeting CACNA1C. Conclusions Our studies revealed that miR-135b is a critical regulator of cardiomyocyte hypertrophy. Our findings may provide a novel strategy for the treatment of cardiac hypertrophy.

Bi12TiO20-based composite ceramics were prepared by sintering a mixture of presynthesized Bi12TiO20 and a second phase around the melting point of Bi12TiO20. These ceramics can exhibit direct as well as inverse piezoelectricity without electrical polarization, and become competitive piezoelectric material with high depoling temperature and stable thermal behavior. However, their piezoelectric constants were, in general, relatively low and do not remain consistent for both the symbol and magnitude over the entire surface. To prevent the permeation of melting Bi12TiO20 into substrate and thus create the inhomogenous amorphous content, samples were sintered on Al2O3 (0001) single crystal substrate. Compared to samples sintered on Al2O3 ceramics, piezoelectric coefficient (d33) of these samples was increased by 80%. Moreover, the symbol of d33 is identical on the whole surface. Here, the enhanced piezoelectricity might be ascribed to increased alignment of distorted BiO5 polyhedra in amorphous Bi12TiO20 phase. These results provided a method to improve the piezoelectric properties of Bi12TiO20-based ceramics and provided some inspiration for further development of Bi12TiO20-based ceramics suitable for practical applications.

Background: Ganglion cell paraganglioma is a subtype of neuroendocrine tumors, which is rare in clinical practice. Paraganglioma in the spinal area, especially in the spinal canal, is even rarer.Case presentation:The case we reported was a 46-year-old female who was admitted to the hospital due to "physical examination found a mass in the lumbar spinal canal for more than 2 months." After admission, the relevant examinations and preoperative preparations were perfected, and the posterior L2-3 spinal mass resection + spinal decompression + nail rod system internal fixation was performed. The patient recovered well after the operation, and there was no tumor recurrence in follow-up. Conclusions:Surgical treatment assisted by MRI neuroimaging and 3D printing reconstruction technology may be an effective way to treat paraganglioma in the lumbar spinal canal.

This chapter discusses the basic concept and techniques for Monte Carlo simulation. The simulation methods for a single random variable as well as those for a random vector (consisting of multiple variables) are discussed, followed by the simulation of some special stochastic processes, including Poisson process, renewal process, Gamma process and Markov process. Some advanced simulation techniques, such as the importance sampling, Latin hypercube sampling, and subset simulation, are also addressed in this chapter.

This chapter discusses the method and application in practical engineering of structural reliability assessment. Reliability theory is the basis for measuring structural safety level under a probability-based framework. This chapter starts from the definition of structural reliability and reliability index, followed by the computation methods of reliability index, including first-order second-moment method, first-order reliability method, simulation-based method and moment-based method. Subsequently, some simple models for system reliability are presented, namely series system, parallel system and k-out-of-n system. The probability-based modelling of structural resistance and external loads are also addressed, followed by the probability-based limit state design approaches. The reliability theory can be further used to optimize structural design and conduct life-cycle cost analysis. Finally, the evaluation of structural reliability in the presence of imprecisely-informed random variables is considered.

This chapter discusses the approaches for structural time-dependent reliability assessment. The significant difference between the time-dependent reliability and the classical reliability (c.f. Chap. 4) is the involvement of the time-variant characteristics in the analysis, where the variation of both the structural resistance and the external loads on the temporal scale should be reasonably modelled. This chapter starts from the motivation of time-dependent reliability assessment, followed by the modelling techniques of the resistance deterioration and the external load processes. Both the discrete and continuous load processes are discussed. Subsequently, the time-dependent reliability assessment approaches in the presence of both the discrete and the continuous loads are addressed. The comparison between the reliabilities associated with the two types of load processes is also presented.

BackgroundBoth hemoglobin A1c (HbA1c) levels and visit-to-visit variability of lipid profiles are risk factors for cardiovascular disease (CVD). We conducted a retrospective cohort study to explore the relationship between HbA1c and lipid variability.MethodsWe retrospectively collected baseline and follow-up data on patients who underwent elective percutaneous coronary intervention (PCI) from January 2009 to April 2019. Univariate and multivariate linear regression analyses were performed to assess the association between HbA1c and lipid variability. Subgroup analyses employed multivariate linear regression analyses.ResultsA total of 4,445 patients were enrolled in the study. The median age and value of HbA1c were 64yrs old and 5.9%, respectively, 64% had hypertension and 25.5% diabetes. The variability of low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), total cholesterol (TC), and triglyceride (TG) was each significantly higher in patients with HbA1c≥6.5% than those with HbA1c＜6.5% group. Multivariate linear regression indicated that HbA1c level was a potential risk factor for the variability of LDL-C, non-HDL-C, TC and TG, which was independent of the mean values of lipids. Subgroup analyses demonstrated that the relationship between HbA1c and the variability of LDL-C, non-HDL-C, TC, and TG did not importantly vary across several subgroups. These results remained consistent when lipid variability was represented by the standard deviation (SD), coefficient of variation (CV) and variability independent of the mean (VIM), respectively.ConclusionHbA1c is a potential risk factor for the variability of LDL-C, non-HDL-C, TC and TG in patients undergoing elective PCI.

We have synthesized a new series of layered oxyselenides Bi 2 LnO 4 Cu 2 Se 2 (Ln=Nd, Sm, Eu, Dy, Er, Yb). Their crystal structures and physical properties were studied through X-ray diffraction, electric transport measurements, bulk magnetization and first-principle calculation. All these compounds have a tetragonal structure with space group I4/mmm. They exhibit hole-type metallic behaviours which is also verified by the DFT calculation. The new Bi 2 LnO 4 -type block in these compounds may give people some enlightenment in synthesizing new iron-based superconductors or other layered compounds.

Scar formation can lead to glaucoma filtration surgery (GFS) failure, wherein transforming growth factor (TGF)-β is the core regulator. To reducing scar formation, this paper presents our study on the design of hydrogels to deactivate TGF-β1. We hypothesized that excess TGF-β1 can be removed from aqueous humor through the addition of oxidized hyaluronic acid (O-HA) hydrogels that are seeded with decorin (O-HA ​+ ​D). Immunohistochemistry and enzyme-linked immunosorbent assay (ELISA) were performed to demonstrate the adsorption properties of O-HA ​+ ​D hydrogel, thus reducing the TGF-β1 concentration in aqueous humor. In the light that collagen contraction in human Tenon's capsule fibroblasts (HTFs) and the angiogenesis of human umbilical vein endothelial cells (HUVECs) can be activated by TGF-β1 and β2, we performed the quantitative analysis of polymerase chain reaction to determine the effect of O-HA ​+ ​D on the type I collagen, fibronectin, and angiogenesis. Our results illustrate that O-HA ​+ ​D can inhibit the increase of α-SMA expression in HTF induced by TGF-β1 and that O-HA ​+ ​D can inhibit the production of collagen I and fibronectin in HTF treated with TGF-β1. Furthermore, we performed in vivo studies by employing a rabbit model, where rabbits were treated with hydrogels post GFS. Our results demonstrate that, as compared with other groups, the rabbits treated with O-HA ​+ ​D had the greatest reduction in inflammatory cells with reduced level of collagen in wounds. Taken together, the present study paves the way toward the treatment of post-glaucoma fibrosis following surgery.

Neuroinflammation is one of the major processes that trigger neuropathological amyloid-β (Aβ) deposition and contribute to Alzheimer’s disease (AD) progression. Naked mole rats, which are the longest living rodents and exhibit negligible senescence, have a special brain microenvironment characterized by high-molecular-mass hyaluronan (HMM-HA) and high levels of neuregulin 1 (NRG1), which are related to resistance to neuroinflammation and Aβ deposition, leading to protection from AD. Thus, mimicking the unique brain microenvironment of the naked mole rat as a strategy for AD treatment is of critical interest. Here, naked mole rat HMM-HA and NRG1 were used to establish an injectable neuroinflammation-responsive triglycerol monostearate (TM)-HA-NRG1 hydrogel to alter the brain microenvironment in the early to late stages of AD. Intracerebroventricular (ICV) delivery of the hydrogel resulted in significant mitigation of Aβ plaque formation and complement C1q deposition in the hippocampus. Interestingly, we found that C1q deposition on pericytes was probably associated with capillary dysfunction. Furthermore, continuous intervention obviously reduced C1q deposition on pericytes and improved the oxygen supply to the brain. Importantly, in 16-month-old AD mice, cognitive decline was significantly ameliorated after TM-HA-NRG1 hydrogel treatment. Thus, the work reported here provides a potential early intervention strategy for retarding later AD progression.

(CoCrFeNi)94Ti2Al4 high entropy alloy (HEA) was fabricated through drop-casting and conventional thermo-mechanical processing. After cold rolling and recrystallization heat treatments, the tensile properties were investigated at room temperature (RT), 573 K, and 873 K, respectively. At RT, the stress-strain curve exhibits non-serration. However, with the increasing tensile temperature from 573 K to 873 K, the serration evolves from type A + B to type C, and the maximum stress drop rises from 15.0 MPa to 24.7 MPa. At 873 K, C-type serration first appears at the yield strain, but finally disappears when the plastic strain above 12%. Transmission electron microscopy (TEM) analysis indicates that the simultaneous effects of twinning boundary and high density dislocations promote the dynamic precipitation of nanoscale L21-Heusler phase during tensile deformation.