The mutiferroic xBiFeO₃–(1−x)BaTiO₃ (BFO–BT: x = 1.0, 0.9, 0.8, and 0.7) ceramics have been synthesized by the solid-state-reaction method with density higher than 90% of the theoretical value. ...Structural transition of BFO–BT ceramics were investigated by using in-situ high-resolution synchrotron X-ray diffraction upon heating. The Curie temperature (TC) shifts toward lower temperature as BT content increases. This work suggests that the BT-substitution can enhance the dielectric response (or permittivity) at room temperature and also decreases the dielectric loss. The highest polarization attainable was improved from ∼0.01 μC/cm² in BFO to ∼1.8 μC/cm² in BFO-30%BT.
Summary
The treatment of 300-mg/day isoflavones (aglycone equivalents) (172.5 mg genistein + 127.5 mg daidzein) for 2 years failed to prevent lumbar spine and total proximal femur bone mineral ...density (BMD) from declining as compared with the placebo group in a randomized, double-blind, two-arm designed study enrolling 431 postmenopausal women 45–65 years old.
Introduction
This study evaluated the effects of soy isoflavones on bone metabolism in postmenopausal women.
Methods
Four hundred and thirty-one women, aged 45–65 years, orally consumed 300-mg/day isoflavones (aglycone equivalents) or a placebo for 2 years in a parallel group, randomized, double-blind, two-arm study. Each participant also ingested 600 mg of calcium and 125 IU of vitamin D
3
per day. The BMD of the lumbar spine and total proximal femur were measured using dual-energy X-ray absorptiometry at baseline and every half-year thereafter. Serum bone-specific alkaline phosphatase, urinary N-telopeptide of type 1 collagen/creatinine, and other safety assessments were examined regularly.
Results
Two hundred out of 217 subjects in the isoflavone group and 199 out of 214 cases in placebo group completed the treatment. Serum concentrations of isoflavone metabolites, genistein and daidzein, of the intervention group were remarkably elevated following intake of isoflavones (
p
< 0.001). However, differences in the mean percentage changes of BMD throughout the treatment period were not statistically significant (lumbar spine,
p
= 0.42; total femur,
p
= 0.39) between the isoflavone and placebo groups, according to the generalized estimating equation (GEE) method. A significant time trend of bone loss was observed at both sites as assessed by the GEE method following repeated measurement of BMD (
p
< 0.001). Differences in bone marker levels were not significant between the two treatment groups.
Conclusion
Treatment with 300-mg/day isoflavones (aglycone equivalents) failed to prevent a decline in BMD in the lumbar spine or total femur compared with the placebo group.
Pure Ni and three Ni–Co alloys films, i.e. Ni–4wt.%Co, Ni–18wt.%Co, and Ni–40wt.%Co, are electrodeposited at room temperature from the choline chloride/ethylene glycol deep eutectic solvent dissolved ...by nickel or/and cobalt chlorides. Electrodeposition mechanism, microstructure, and corrosion properties of the films are investigated. Surface morphology and chemical composite of the films are significantly dependent on the Ni2+ and Co2+ concentrations in the electrolytes. Interestingly, it is found that the amount of cobalt in the Ni–Co alloy films is significantly lower than that present in the electrolytes, which indicates an absence of anomalous codeposition process for the non-aqueous electrolytes. However, anomalous codeposition of Ni–Co deposits is frequently observed for the aqueous electrolytes. The Ni–Co alloy films possess face-centered cubic structures and refined grains revealed by X-ray diffractometer and scanning electron microscope. Potentiodynamic polarization measurements show that the Ni film exhibits the noblest corrosion potential and the lowest corrosion current compared with the Ni–Co alloys films. Moreover, the more Co content the Ni–Co films have, the more negative corrosion potential and the higher corrosion current the films exhibit.
► Electrodeposition of Ni–Co films from a deep eutectics system. ► Co2+ concentrations influence surface morphology and chemical composite of films. ► Ni–Co deposition with a non-anomalous codeposition process.
In order to clarify the reason for the differences in the fretting wear resistance of Inconel 690 and 600 plate against 304 stainless steel ball, which is conducive to deepening the understanding of ...degradation mechanism, the comparative study on wear scars of two materials have been conducted in the atmosphere. The results indicated that Inconel 690 exhibited more excellent wear resistance than Inconel 600, which could be attributed to the thicker and harder tribological transformed structure (TTS) formed in worn subsurface of Inconel 690. The further structural characterizations of subsurface showed that the transformation mechanism from the matrix (coarse grains) to TTS (nano-sized grains) was dynamic recrystallization. Compared with Inconel 600, Inconel 690 possessed lower stacking fault energy (SFE) for its high chromium content, which prompted the occurrence of dynamic recrystallization and eventually led to a harder and thicker TTS in Inconel 690 worn subsurface.
Inconel 690 presented more excellent wear performance than Inconel 600 as its thicker tribological transformed structure formed by dynamic recrystallization. Display omitted
•There are stratified structures formed in worn subsurface of Inconel 690 and 600.•The general deformed layer (GDL) consists of striplike twins and subgrains.•The tribological transformed structure (TTS) consists of equiaxed nanosized grains.•The transformation from matrix to TTS is dynamic recrystallization.•Inconel 690 presents more excellent wear resistance than Inconel 600 for its thicker and harder TTS.
In this work, we carry out theoretical investigation of the dispersion relationship both with the radius of the microsphere cavity and wavelength for the first two radial-order mode based on the ...theory of microcavity dispersion. The results show that the size of the microcavity corresponding to the zero dispersion point of the higher order mode is larger than that of lower order mode at the certain wavelength. The microsphere cavities with slight deformations, which have rich modes and high Q values, have been fabricated and optical frequency comb (OFC) in them with small size is realized by means of mode coupling. We have achieved OFC in cavities as small as 105 μm in diameter by assistance of the theoretical study. The total dispersions are −7.1 MHz in 1550 nm and −14.2 MHz in 1310 nm, which are both in the normal dispersion region.
Structure and piezoelectric coefficient (d33) of lead‐free 7.5% mole BaTiO3‐doped (Bi0.5Na0.5) TiO3 (BNT‐7.5%BT) polycrystalline piezoceramics have been characterized systematically as a function of ...poling electric (E) field. Dielectric permittivity and loss were also measured as functions of frequency and temperature. The piezoelectric coefficient d33 after poling at E = 35 kV/cm can reach d33~186 pC/N, which is the highest value reported among (1−x) BNT–xBT compositions. A prior poling E field can reduce rhomobherdal lattice distortion, and enhance tetragonal phase and polarization ordering, that contribute significantly to the rapid raise of d33 and lower depolarizing temperature (Td). The reduced dielectric permittivity for the poled sample is attributed to ordered state and the pinning of field‐induced nanodomain walls by the presence of oxygen vacancies.
We evaluated the impact of lumbar instrumented circumferential fusion on the development of adjacent level vertebral compression fractures (VCFs). Instrumented posterior lumbar interbody fusion ...(PLIF) has become a popular procedure for degenerative lumbar spine disease. The immediate rigidity produced by PLIF may cause more stress and lead to greater risk of adjacent VCFs. However, few studies have investigated the relationship between PLIF and the development of subsequent adjacent level VCFs. Between January 2005 and December 2009, a total of 1936 patients were enrolled. Of these 224 patients had a new VCF and the incidence was statistically analysed with other covariants. In total 150 (11.1%) of 1348 patients developed new VCFs with PLIF, with 108 (72%) cases at adjacent segment. Of 588 patients, 74 (12.5%) developed new subsequent VCFs with conventional posterolateral fusion (PLF), with 37 (50%) patients at an adjacent level. Short-segment fusion, female and age older than 65 years also increased the development of new adjacent VCFs in patients undergoing PLIF. In the osteoporotic patient, more rigid fusion and a higher stress gradient after PLIF will cause a higher adjacent VCF rate.
Deep neural networks (DNNs) have been introduced to achieve the rapid design of photonic devices by creating a nonlinear function mapping the geometric structure to the optical response. By building ...the DNN with a finite-difference time-domain (FDTD) solver, we have demonstrated that both forward and inverse design approaches can be used to design efficiently a silicon photonic grating coupler-one of the fundamental silicon photonic devices with a wavelength-sensitive optical response, respectively. A systematic study on the model parameters including number of hidden layers, number of nodes in each layer, initial learning rate, size of training batches, number of evolution epochs, and dataset size/distribution has been carried out to analyze the relationship between the DNNs and the performances of inverse-designed devices. The study shows that the forward design approach based on an optimal forward-modeling network can achieve a peak coupling efficiency with a prediction accuracy as high as 91.7% for the coupler. And the inverse design approach based on an optimal inverse-prediction network can obtain target optical response spectrum as well as provide possibility to get an alternative design for the device. This work is helpful for the designers to improve the machine learning methods and expedite the design progress towards the creation of novel silicon photonic devices.
Three forms of cell death have been described: apoptosis, autophagic cell death, and necrosis. Although genetic and biochemical studies have formulated a detailed blueprint concerning the apoptotic ...network, necrosis is generally perceived as a passive cellular demise resulted from unmanageable physical damages. Here, we conclude an active de novo genetic program underlying DNA damage-induced necrosis, thus assigning necrotic cell death as a form of "programmed cell death." Cells deficient of the essential mitochondrial apoptotic effectors, BAX and BAK, ultimately succumbed to DNA damage, exhibiting signature necrotic characteristics. Importantly, this genotoxic stress-triggered necrosis was abrogated when either transcription or translation was inhibited. We pinpointed the p53-cathepsin axis as the quintessential framework underlying necrotic cell death. p53 induces cathepsin Q that cooperates with reactive oxygen species (ROS) to execute necrosis. Moreover, we presented the in vivo evidence of p53-activated necrosis in tumor allografts. Current study lays the foundation for future experimental and therapeutic discoveries aimed at "programmed necrotic death."
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