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Men are traditionally portrayed as being successful in sports, and male teachers in physical activities are portrayed as successful teachers. How do female teachers perceive the gender role of kindergarten teachers in early childhood physical activities? Using hegemonic masculinity theory as an analytical tool, semi-structured interviews with female public kindergarten teachers from four cities in Zhejiang Province, China were conducted. The study found that although most Chinese female teachers had traditional gender stereotypes about the role of physical activity teachers in kindergartens, these gender stereotypes were not firmly established. As the questions were contextualized and deepened, thinking about the deeper elements of early childhood physical activity was activated. They did not seem to believe that women were incapable of leading young children in physical activities, nor did they believe that women were not important in ideal early childhood physical activities. By deconstructing the male-only nature of 'hegemonic masculinity', they reconstructed the masculinity that children need in early childhood physical activities and constructed a more equal concept of teachers' gender in early childhood physical activities. [ABSTRACT FROM AUTHOR]

While studies have explored the physical literacy of Chinese kindergarten teachers and its impact on young children’s health, to date, none has provided a comprehensive analysis of Chinese kindergarten teachers’ self-perceptions in relation to sport. This study explored the environmental stressors associated with participating in sport during the teenage years of 148 Chinese female pre-service kindergarten teachers majoring in early childhood education at a Chinese university through the analysis of their individual sports life history texts. The researchers found that there were multiple simultaneous pressures regarding girls’ sport participation in China. First, there is the pain of student sports participation caused by the pull of multiple forces, and the inconsistency between government, school, family, and student demands for sports, which makes both sports and students a passive presence. Second, there is gender discrimination against women in the sports arena, which adds another burden for girls. Third, physical education teachers seem to have been unable to solve the physical and mental discomforts caused by perceptions of girls’ limited ability, accidental injuries, anxiety and shyness in the sports process. The study revealed the profound impact of body culture and gender culture in Confucianism on adolescent girls’ sports during puberty. The findings contribute to understanding and improving the pre-service physical education practices of female kindergarten teachers and female physical education practices during adolescence, as well as, in the long run, improving the quality of kindergarten children’s physical activity in a context where females are the dominant occupational group. [ABSTRACT FROM AUTHOR]

Reducing mechanical losses and suppressing self‐heating are critical characteristics for high‐power piezoelectric applications. For environmentally friendly Pb‐free piezoelectric ceramics, traditional acceptor doping or annealing treatments have successfully improved the mechanical quality factor (Qm) based on a ceramic matrix with a poor piezoelectric coefficient (d33<100 pC/N). Nevertheless, a ceramic with high Qm and d33 values has not been reported owing to the inverse relationship between Qm and d33. Herein, a novel hardening method called grain boundary diffusion is used to develop Pb‐free potassium sodium niobate ceramics, where Qm increased by more than two‐fold (from 51 to 132) and a high d33 value (d33 = 360 pC/N) is maintained. Significantly, d33 retained 98% of its initial value after 180 days, exhibiting improved aging stability. The established properties are associated with the formation of the core‐shell microstructure and the full gradient composition distribution using structural characterizations and phase‐field simulations, where the core maintains a high d33 and the shell provides a hardening effect. The novel hardening effect in piezoelectric materials, known as grain boundary diffusion hardening, highlights the enhancement of the mechanical quality factor with high piezoelectricity, providing a new paradigm for the design of functional materials. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to assess the feasibility and outcomes of standardized three-dimensional (3D)-printed trabecular titanium (TT) cups and augments to reconstruct most acetabular defects. Methods: We included 58 patients with Paprosky type II and III acetabular bone defects who underwent revision hip arthroplasty between 2015 and 2018. Patients who were revised without 3D-printed augments, and cases who were lost to follow-up and died during follow-up were excluded. Radiographic and clinical outcomes were evaluated. A Kaplan–Meier survivorship curve was generated. The mean follow-up was 64.5 (range 49–84) months. Results: In total, 48 (82.8%) acetabular revisions were performed using standardized 3D-printed TT cups and augments, and a retrospective review was conducted on 43 revisions. The average position of the vertical center of rotation and leg length discrepancy were significantly decreased from 42.4 ± 9.1 mm and 38.4 ± 10.7 mm to 22.8 ± 3.4 mm and 4.1 ± 3.0 mm, respectively. Non-progressive radiolucent lines were observed in 3 (7.5%) acetabular components with no indications for revision. The mean Harris hip score, Oxford hip score and EuroQol five-dimensional questionnaire score increased from 33.0 ± 10.7, 11.4 ± 3.4 and 0.29 ± 0.09 to 80.3 ± 8.8, 35.8 ± 2.4 and 0.71 ± 0.10, respectively. The revision-free survival rate of the acetabular component was 93.0% (40/43), with a rate of revision for aseptic loosening of 2.3% (1/43). Conclusion: Standardized 3D‑printed TT augments and cups could be used to reconstruct the majority of Paprosky type II and III acetabular defects in revision hip arthroplasty and demonstrated encouraging results at mid-term follow-up. [ABSTRACT FROM AUTHOR]

SUMMARY: PROTEIN l‐ISOASPARTYL O‐METHYLTRANSFERASE (PIMT) affects seed vigor by repairing damaged proteins. While PIMT is capable of isoaspartyl (isoAsp) repair in all proteins, those proteins most susceptible to isoAsp formation have not been well characterized, and the mechanisms by which PIMT affects seed vigor remain largely unknown. Using co‐immunoprecipitation and LC‐MS/MS, we found that maize (Zea mays) PIMT2 (ZmPIMT2) interacted predominantly with both subunits of maize 3‐METHYLCROTONYL COA CARBOXYLASE (ZmMCC). ZmPIMT2 is specifically expressed in the maize embryo. Both mRNA and protein levels of ZmPIMT2 increased during seed maturation and declined during imbibition. Maize seed vigor was decreased in the zmpimt2 mutant line, while overexpression of ZmPIMT2 in maize and Arabidopsis thaliana increased seed vigor upon artificial aging. ZmPIMT2 was localized in the mitochondria, as determined by subcellular localization assays using maize protoplasts. ZmPIMT2 binding to ZmMCCα was confirmed by luciferase complementation tests in both tobacco (Nicotiana benthamiana) leaves and maize protoplasts. Knockdown of ZmMCCα decreased maize seed aging tolerance. Furthermore, overexpression of ZmPIMT2 decreased the accumulation of isoAsp of ZmMCCα protein in seed embryos that underwent accelerated aging treatment. Taken together, our results demonstrate that ZmPIMT2 binds ZmMCCα in mitochondria, repairs isoAsp damage, and positively affects maize seed vigor. Significance Statement: PROTEIN l‐ISOASPARTYL METHYLTRANSFERASE (PIMT) positively affects orthodox seed vigor, repairing abnormal protein isoaspartate (isoAsp) to Asp; however, how seed vigor is exactly affected remains unclear. Maize (Zea mays) mitochondrial 3‐METHYLCROTONYL COA CARBOXYLASE (ZmMCC) positively influences seed vigor, yet accrues isoAsp. ZmPIMT2, also mitochondrially localized, interacts with, and repairs, the isoAsp‐damaged ZmMCC. These results have led to a better understanding of the foundations of seed vigor. [ABSTRACT FROM AUTHOR]

Niobate‐based lead‐free piezoceramics have attracted wide attention due to their excellent piezoelectric properties. Although the temperature sensitivity of piezoelectricity or strain in one sample has been solved to a certain extent, how to simultaneously improve the temperature stability of both in one sample is still an issue. Herein, by constructing multilayer composite ceramics and doping Ho element, both improved piezoelectric and strain temperature stability (the variations are below 3% under 30–100 °C) are achieved, showing great property advantage compared with previous reports. Different from the compositionally graded composite ceramic design, the Ho doping can not only increase orthorhombic‐tetragonal phase transition temperature (TO‐T) and then create the condition for the formation of successive phase transition, but also stabilize the oriented domain state. Therefore, the excellent temperature stability of both piezoelectricity and strain can be attributed to the multistep phase transition induced by the multilayer design, the fine regulation of TO‐T interval by the optimization of lamination combination, and the stabilized polarization induced by Ho doping. The new strategy for solving both piezoelectric and strain temperature sensitivity can further promote the commercial application of potassium sodium niobate‐based lead‐free piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

The detection of deep‐seated lesions is of great significance for biomedical applications. However, due to the strong photon absorption and scattering of biological tissues, it is challenging to realize in vivo deep optical detections, particularly for those using the safe laser irradiance below clinical maximum permissible exposure (MPE). In this work, the combination of ultra‐bright surface‐enhanced Raman scattering (SERS) nanotags and transmission Raman spectroscopy (TRS) is reported to achieve the non‐invasive and photosafe detection of "phantom" lesions deeply hidden in biological tissues, under the guidance of theoretical calculations showing the importance of SERS nanotags' brightness and the expansion of laser beam size. Using a home‐built TRS system with a laser power density of 0.264 W cm−2 (below the MPE criteria), we successfully demonstrated the detection of SERS nanotags through up to 14‐cm‐thick ex vivo porcine tissues, as well as in vivo imaging of "phantom" lesions labeled by SERS nanotags in a 1.5‐cm‐thick unshaved mouse under MPE. This work highlights the potential of transmission Raman‐guided identification and non‐invasive imaging toward clinically photosafe cancer diagnoses. [ABSTRACT FROM AUTHOR]

Posttraumatic headache (PTH) attributed to traumatic brain injury (TBI) is a secondary headache developed within 7 days after head injury, and in a substantial number of patients PTH becomes chronic and lasts for more than 3 months. Current medications are almost entirely relied on the treatment of primary headache such as migraine, due to its migraine-like phenotype and the limited understanding on the PTH pathogenic mechanisms. To this end, increasing preclinical studies have been conducted in the last decade. We focus in this review on the trigeminovascular system from the animal studies since it provides the primary nociceptive sensory afferents innervating the head and face region, and the pathological changes in the trigeminal pathway are thought to play a key role in the development of PTH. In addition to the pathologies, PTH-like behaviors induced by TBI and further exacerbated by nitroglycerin, a general headache inducer through vasodilation are reviewed. We will overview the current pharmacotherapies including calcitonin gene-related peptide (CGRP) monoclonal antibody and sumatriptan in the PTH animal models. Given that modulation of the endocannabinoid (eCB) system has been well-documented in the treatment of migraine and TBI, the therapeutic potential of eCB in PTH will also be discussed. [ABSTRACT FROM AUTHOR]

Under global warming, the frequent occurrence of Eurasian extreme cold events in the Northern Hemisphere in recent years has attracted widespread attention. Winter Eurasia near‐surface anticyclone activities are closely related to low temperatures. This study uses a new objective anticyclone identification algorithm based on a Mask region‐based convolutional neural network (Mask R‐CNN) to detect long‐term winter Eurasian anticyclone activities. We found that most tracks of Eurasian anticyclones (30.5%) pass Siberia in winter. Anticyclone tracks over Siberia can be well separated into the eastward moving type, the northwest–southeast type, and the local type, with distinct associated circulation patterns. The energy dispersions of upstream Rossby waves have an important influence on the movement, maintenance and intensification of the three types. In association with anticyclones intensifying in Siberia, surface air temperatures in the mid‐latitudes of Eurasia, especially Siberia, are significantly lower. In particular, the local type is the most active (56.1%) and is significantly correlated with the winter temperature anomaly in most areas of East Asia. Further research indicates that the preceding autumn sea ice condition in the Barents Sea can be used as a precursor factor to modulate the local type anticyclone activity and winter temperature anomaly in East Asia. In years of less ice, a quasi‐meridional wave activity flux originating from the Barents Sea is more active, and the centre SLP of the local type anticyclone is higher with more cold air mass carried, which in turn results in colder weather in Siberia, the Mongolian Plateau and East Asia. [ABSTRACT FROM AUTHOR]

Abstract Censored data are nearly ubiquitous in survival analysis. If the proportional hazard assumption is invalid, traditional test methods, such as the log-rank tests, rapidly lose power. In this article, a new slope strategy is presented to improve the power of the test. The aim of this study is to establish effective tests that are familiar in biomedical research and medical practice for censored data. Four tests based on slope are proposed in this article, and Monte Carlo simulations with different survival curves, sample sizes, and censoring rate scenarios are performed to evaluate the test power. Four common tests, the log-rank test, Gehan–Wilcoxon test, and Fleming–Harrington with different parameters, are compared with four new slope tests. The slope tests are more effective when the censoring rate is greater than or equal to 30%, especially for scenarios involving early hazard function differences. Two clinical cases also indicate that the proposed slope methods can detect differences for real data. Slope tests may supplement computing methods of survival curve tests, and they will be more useful when considering higher censoring rates. [ABSTRACT FROM AUTHOR]

Alternariol (AOH) is a metabolic product of Alternaria , which has various toxic effects on humans and animals and its pollution is increasingly being discovered in fruits, vegetables, and grains. At present, the detection of AOH is mainly achieved through high-performance liquid chromatography-mass spectrometry and immunological methods. However, there is currently a lack of fast detection methods for on-site use. Considering the unique advantages of immunological testing methods, this study developed an immunolateral chromatographic quantitative method for detecting AOH using quantum dot fluorescent nanospheres (QDFNs) as signal amplification materials. The detection range of AOH is 5.2–4798 μg/kg, 50 % inhibiting concentration (IC 50) is 156.4 μg/kg, limit of detection (LOD) value is 2.32 μg/kg, and limit of quantification (LOQ) value is 6.96 μg/kg. The recovery rates of AOH in tomato and strawberry were 95.27%–111.63% and 88.43%–96.22%, respectively. In brief, the developed approach has good accuracy and repeatability and can be used for the detection of AOH. • Quantum dot fluorescent nanosphere coupled with antibody was used as detection probe. • Established an immunological chromographic quantitative method for detection of AOH. • The detection range of method is 5.2–4798 μg/kg, with a limit of detection of 2.32 μg/kg. • Our designed test strips can serve as potential point-of-care testing platform for detection. [ABSTRACT FROM AUTHOR]

Deep learning-based computer-aided diagnosis has garnered significant attention in both academic research and clinical applications. Due to the challenges in collecting well-labeled clinical data, unsupervised domain adaptation methods have become widely used in medical image analysis. However, existing unsupervised domain adaptation methods in the clinic field fail to adapt to scenarios where new, unlabeled target data continually arrive in an online manner. To tackle this real-world clinical challenge, a meta-adaptation framework is innovatively developed, termed consecutive lesion knowledge meta-adaptation, primarily comprising semantic adaptation and representation adaptation phases. Specifically, the semantic knowledge learned from the source lesion domain will be transferred to the consecutive target lesion in the semantic adaptation phase. To further align the transferable representation knowledge across the source and multiple target lesion domains, the feature-extractor is optimized in the representation adaptation phase. Furthermore, to mitigate catastrophic forgetting during continuous unsupervised domain adaptation, a domain-quantizer is designed to preserve utility knowledge from previously learned target lesion domains. Moreover, as semantic knowledge is continuously evolving and artificially designed kernels struggle to model such complex distributions, a self-adaptive kernel is designed to flexibly measure the shift between the source and consecutive target lesion domains during the semantic adaptation phase. Experimental results on medical image classification tasks demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In recent decades, photoluminescence (PL) material with excellent optical properties has been a hot topic. Graphene oxide (GO) is an excellent candidate for PL material because of its unique optical properties, compared to pure graphene. The existence of an internal band gap in GO can enrich its optical properties significantly. Therefore, GO has been widely applied in many fields such as material science, biomedicine, anti-counterfeiting, and so on. Over the past decade, GO and quantum dots (GOQDs) have attracted the attention of many researchers as luminescence materials, but their luminescence mechanism is still ambiguous, although some theoretical results have been achieved. In addition, GO and GOQDs have fluorescence quenching properties, which can be used in medical imaging and biosensors. In this review, we outline the recent work on the photoluminescence phenomena and quenching process of GO and GOQDs. First, the PL mechanisms of GO are discussed in depth. Second, the fluorescence quenching mechanism and regulation of GO are introduced. Following that, the applications of PL and fluorescence quenching of GO–including biomedicine, electronic devices, material imaging–are addressed. Finally, future development of PL and fluorescence quenching of GO is proposed, and the challenges exploring the optical properties of GO are summarized. [ABSTRACT FROM AUTHOR]

Streptococcus suis is an important emerging zoonosis that causes economic losses in the pig industry and severe threats to public health. Transcriptional regulators play essential roles in bacterial adaptation to host environments. In this study, we identified a novel XRE family transcriptional regulator in S. suis CZ130302, XtrSs, involved in the bacterial fitness to hydrogen peroxide stress. Based on electrophoretic mobility shift and β-galactosidase activity assays, we found that XtrSs auto-regulated its own transcription and repressed the expression of its downstream gene psePs, a surface protein with unknown function in S. suis, by binding to a palindromic sequence from the promoter region. Furthermore, we proved that the deletion of the psePs gene attenuated bacterial antioxidant response. Phylogenetic analysis revealed that XtrSs and PsePs naturally co-existed as a combination in most S. suis genomes. Collectively, we demonstrated the binding characteristics of XtrSs in S. suis and provided a new insight that XtrSs played a critical role in modulating psePs to the hydrogen peroxide resistance of S. suis. [ABSTRACT FROM AUTHOR]

Wave frequency is a critical parameter for applications ranging from human hearing, acoustic non-reciprocity, medical imaging to quantum of energy in matter. Frequency alteration holds the promise of breaking limits imposed by the physics laws such as Rayleigh's criterion and Planck–Einstein relation. We introduce a linear mechanism to convert the wave frequency to any value at will by creating a digitally pre-defined, time-varying material property. The device is based on an electromagnetic diaphragm with a MOSFET-controlled shunt circuit. The measured ratio of acoustic impedance modulation is up to 45, much higher than nonlinearity-based techniques. A significant portion of the incoming source frequency is scattered to sidebands. We demonstrate the conversion of audible sounds to infrasound and ultrasound, respectively, and a monochromatic tone to white noise by a randomized MOSFET time sequence, raising the prospect of applications such as super-resolution imaging, deep sub-wavelength energy flow control, and encrypted underwater communication. Temporal modulation materials have been attracting attention thanks to their ability to break wave reciprocity, i.e., waves traveling from point A to B are identical to waves propagating from B to A. The authors present a linear temporal modulation device with a giant acoustic impedance modulation ratio and ability to linearly change wave frequency, operating in two quantized states when a shunt circuit is connected and disconnected by a MOSFET. [ABSTRACT FROM AUTHOR]

Background. The number of articles of clinical and basic research for osteonecrosis of the femoral head (ONFH) is increasing, yet, to our knowledge, there is still a lack of bibliometric analysis on ONFH articles. The purpose of this study was to identify the top 100 cited (T100) articles related to ONFH research and to analyze the characteristics and qualities of these articles. Methods. The T100 articles on ONFH were retrieved from the Web of Science database. The information about each article including citations, titles, authors, journals, countries, institutions, and keywords was recorded for bibliometric analysis. Results. The T100 articles related to ONFH were mainly published from 1991 to 2010 (n = 70) and were originated from 24 countries. The USA, China, and Japan were the most productive countries in this regard. The most prolific institution was the University of Pennsylvania from the USA with 6 publications and 742 citations. The most cited article was published in 1995 by Professor Steinberg ME. The five most frequently occurring keywords were "femoral head," "osteonecrosis," "core decompression," "total hip arthroplasty," and "follow up." The keywords like "bone tissue engineering" and "extracorporeal shock wave" have emerged in recent years. Conclusions. The USA, China, and Japan contributed greatly in terms of the T100 articles. The outcomes of core decompression and total hip arthroplasty gathered the most research interests. In recent years, bone tissue engineering and extracorporeal shock wave have become new trends. However, the mechanism of ONFH is still unclear. [ABSTRACT FROM AUTHOR]

The limited penetration of photons in biological tissue restricts the deep-tissue detection and imaging application. The micro-scale spatially offset Raman spectroscopy (micro-SORS) with an optical fiber probe, colleting photons from deeper regions by offsetting the position of laser excitation from the collection optics in a range of hundreds of microns, shows great potential to be integrated with endoscopy for inside-body noninvasive detection by circumventing this restriction, particularly with the combination of surface-enhanced Raman spectroscopy (SERS). However, a detailed tissue penetration study of micro-SORS in combination with SERS is still lacking. Herein, we compared the signal decay of enhanced Raman nanotags through the tissue phantom of agarose gel and the biological tissue of porcine muscle in the near-infrared (NIR) region using a portable Raman spectrometer with a micro-SORS probe (2.1 mm in diameter) and a conventional hand-held probe (9.7 mm in diameter). Two kinds of Raman nanotags were prepared from gold nanorods decorated with the nonresonant (4-nitrobenzenethiol) or resonant Raman reporter molecules (IR-780 iodide). The SERS measurements show that the penetration depths of two Raman nanotags are both over 2 cm in agarose gel and 3 mm in porcine muscle. The depth could be improved to over 4 cm in agarose gel and 5 mm in porcine tissue when using the micro-SORS system. This demonstrates the superiority of optical-fiber micro-SORS system over the conventional Raman detection for the detection of nanotags in deeper layers in the turbid medium and biological tissue, offering the possibility of combining the micro-SORS technique with SERS for noninvasive in vivo endoscopy-integrated clinical application. [ABSTRACT FROM AUTHOR]

Quorum sensing (QS) inhibition is an essential strategy to combat bacterial infection. Previously, we have synthesized a series of thymidine derivatives bearing isoxazole and 1,2,3-triazole rings (TITL). Herein, the inhibitory effects of TITL on QS of Pseudomonas aeruginosa PAO1 were evaluated. In vitro results demonstrated that TITL effectively inhibited biofilm formation and reduced the virulence factors of P. aeruginosa PAO1. In combination with antibiotics, our TITL compounds significantly prolonged the lifespans of Caenorhabditis elegans N2 nematodes that were infected with P. aeruginosa PAO1 in vivo. In conclusion, TITL compounds are promising candidates for the treatment of antibiotic-resistant P. aeruginosa PAO1. [ABSTRACT FROM AUTHOR]

The arginine deiminase system (ADS) has been identified in various bacteria and functions to supplement energy production and enhance biological adaptability. The current understanding of the regulatory mechanism of ADS and its effect on bacterial pathogenesis is still limited. Here, we found that the XRE family transcriptional regulator XtrSs negatively affected Streptococcus suis virulence and significantly repressed ADS transcription when the bacteria were incubated in blood. Electrophoretic mobility shift (EMSA) and lacZ fusion assays further showed that XtrSs directly bind the promoter of ArgR, an acknowledged positive regulator of bacterial ADS, to repress ArgR transcription. Moreover, we provided compelling evidence that S. suis could utilize arginine via ADS to adapt to acid stress, while ΔxtrSs enhanced this acid resistance by upregulating the ADS operon. Moreover, whole ADS-knockout S. suis increased arginine and antimicrobial NO in the infected macrophage cells, decreased intracellular survival, and even caused significant attenuation of bacterial virulence in a mouse infection model, while ΔxtrSs consistently presented the opposite results. Our experiments identified a novel ADS regulatory mechanism in S. suis, whereby XtrSs regulated ADS to modulate NO content in macrophages, promoting S. suis intracellular survival. Meanwhile, our findings provide a new perspective on how Streptococci evade the host’s innate immune system. [ABSTRACT FROM AUTHOR]

• A TDS-UC model incorporating the dynamic characteristics of electricity-gas-heat IES is proposed. • A distributed and parallel analytical target cascading algorithm is developed to decouple the integrated TDS-UC model. • An improved one-dimensional piecewise linear approximation method is employed to to linearize the Weymouth equation. The traditional hierarchical scheduling and operational model of transmission and distribution networks has failed to fully utilize the adjustable resources of the entire grid, consequently limiting the integration of renewable energy. To fully excavate the potential of transmission and distribution (T&D) coordination in enhancing the level of renewable energy assimilation and operational efficiency, in this paper, transmission grid and distribution network in the framework of synergetic unit commitment (TDS-UC) considering the dynamic characteristics of the electricity-gas-heat integrated energy system is proposed. The framework developed in this paper allows for the integration of multiple energy sources, including electricity, gas, and heat, into the dispatch strategy of the TG. To improve scheduling flexibility, the dynamic characteristics of the natural gas and heating networks are also considered in the TDS-UC model. A coordinated interactive optimization model for T&D is formulated, taking into account the multi-energy coupling relationship of the IES. To solve the TDS-UC model, a decentralized analytical target cascading algorithm is used to obtain an independent TG optimization problem and multiple ADNs local optimization problems that can be solved in parallel. The proposed model is transformed into an easy-to-solve mixed-integer linear programming (MILP) problem using an improved one-dimensional approximation piecewise linearization method to deal with the non-convexity nonlinear natural gas Weymouth equation. Numerical experiments are conducted on both a T6D2 and a T118D10 test system to demonstrate the efficiency and practicality of the proposed methodology. © 2017 Elsevier Inc. All rights reserved. [ABSTRACT FROM AUTHOR]

The electrical properties of gallium nitride (GaN) substrate are crucial to the performance of vertical power devices. Bulk GaN substrates with carrier concentrations in the range from 6.7 × 1017 to 1.7 × 1019 cm−3 are grown by hydride vapor phase epitaxy. All samples show no obvious tensile stress regardless of the carrier concentration. Moreover, the mobility of Si-doped high-quality bulk GaN is superior to the GaN template with higher dislocation density at the same carrier concentration. The influence of carrier concentration on the performance of ohmic contact on N-face of Si-doped GaN is also carefully studied by circular transfer length measurement and rapid thermal annealing methods. The specific contact resistivity decreases monotonically with increase of carrier concentration, while it increases with the annealing temperature. The N-face contact becomes non-ohmic when the annealing temperature exceeds the limit value, which increases with the carrier concentration. The sample with carrier concentration of 1.7 × 1019 cm−3 still showed ohmic behavior after annealing at 450 °C. These results are not only useful to improve the electrical properties of N-type bulk GaN substrate, but also provide a potential solution for improving the efficiency of vertical devices in the future. [ABSTRACT FROM AUTHOR]

Based on the design concept of 'strong horizontal joint and weak vertical joint', an energy‐dissipating fabricated shear wall structure system with a steel damper is proposed. The wall limbs were connected using the damper to realize the rapid assembly and improve the seismic performance of the fabricated shear wall structure. Four fabricated shear wall specimens and one cast‐in‐place comparison specimen were prepared, and a low‐cycle repeated load test was carried out under an axial compression ratio of 0.1. Results show that the fabricated shear wall structure features slightly reduced bearing capacity but obviously improved ductility, and the energy dissipation of the damper improves the seismic performance of the structure. The damper can dissipate energy rapidly, reduce the damage degree of the wall limbs and work stably, suggesting its good performance as a connector. [ABSTRACT FROM AUTHOR]

There are a large number of damping materials in high-damping rubber (HDR) bearings, so the HDR bearings have the characteristics of both common rubber bearings and damping measures and show good aseismic effect. In this paper, the time-history dynamic analysis method is used to study the seismic effects of HDR bearings on the aseismic behaviors of two-span simply supported beam bridge under Northridge earthquake by changing the damping characteristics of the bearings. It is found that, with increasing damping of the bearings, both the horizontal shear and the displacement of the HDR bearings decrease, and the seismic energy dissipates through both the yield deformation and damping of the bearings. Although the girder and bearings have smaller displacement, when the HDR bearings with larger damping, the seismic responses, including displacement of pier top, shear force of pier bottom, and bending moment of pier bottom, are hardly affected by the change of the damping of the bearings. The HDR bearings with higher damping and yield characteristics separate and dissipate the seismic energy transmitted to the superstructure of the bridge and have better seismic effect on the structure in an earthquake. [ABSTRACT FROM AUTHOR]

Background: The diet quality among adults receiving nutrition education lessons through Supplemental Nutrition Assistance Program-Education (SNAP-Ed) is currently unknown.Objectives: The objectives of this study were to characterize the diet quality of Indiana SNAP-Ed-eligible women; estimate their mean usual intake of fruits, vegetables, dairy, and whole grains compared to Dietary Guidelines for Americans (DGA) recommendations; and determine if these dietary outcomes differed by food security status.Methods: SNAP-Ed paraprofessionals recruited participants from August 2015 to May 2016 for this secondary analysis of cross-sectional data collected as the baseline assessment for a randomized controlled trial. Participants were SNAP-Ed-eligible women aged ≥18 y interested in nutrition education lessons. Dietary outcomes were assessed by one or two 24-h dietary recalls. The Healthy Eating Index (HEI)-2010 was used to characterize diet quality. Mean usual intake of food groups was estimated using the National Cancer Institute Method. Food security status was classified using the US Household Food Security Survey Module. Data were analyzed in October 2019.Results: Mean ± SEM HEI-2010 total score was 42 ± 0.9 for the study sample. Mean ± SE usual intake of servings of fruits (0.61 ± 0.08 cups [144.32 ± 18.93 mL]), vegetables [1.4 ± 0.10 cups (331.2 ± 23.66 mL)], dairy [1.5 ± 0.11 cups (354.88 ± 26.02 mL)], and whole grains [0.48 ± 0.06 ounces (13.61 ± 1.70 g)] did not differ by food security subgroup. Mean HEI-2010 total score was significantly higher by 4.8 ± 2.0 points for the food-secure than for the food-insecure subgroup (P = 0.01). Mean HEI-2010 component scores were 1.1 ± 0.5 points higher for whole grain (P = 0.01) and 1.0 ± 0.5 points higher for dairy (P = 0.05) in the food-secure than in the food-insecure subgroup. The proportions of the study sample not meeting the DGA recommendations for food group intake were ≥85% for both food-secure and -insecure subgroups.Conclusions: Indiana SNAP-Ed-eligible women reported poor diet quality, highlighting their need for nutrition interventions aiming to improve food security and diet as per DGA recommendations in low-income populations. [ABSTRACT FROM AUTHOR]

An acoustic switch permits or forbids sound transmission through a partition, and its performance is governed by the stiffness and mass laws at low and high frequencies, respectively. The mechanism of artificial mass and stiffness, either positive or negative, is required to break these laws; all are demonstrated experimentally in this study. The switch consists of a suspended diaphragm with electric moving coil and a magnetic field, shunted by an essentially passive analog circuit. We show that electrically mediated damping is extremely large, and its mechanism as a powerful wave stopper can be very broadband, which contrasts with most resonance-based devices in the literature. We also show that a serial shunt capacitor introduces a mechanical mass that softens the diaphragm spring at low frequencies, while a shunt inductance is an electromagnetic spring that pacifies mechanical inertia at high frequencies. By manipulating the dynamic mass, stiffness, and damping electronically to enhance or defy the mass law and stiffness law, a switch effective in over one octave and working at a deep subwavelength scale is realized, and the maximum switch ratio is as high as 28 dB. As circuits can be miniaturized and easily tuned, these illustrated physics point to a versatile tool for digital control of sound waves. [ABSTRACT FROM AUTHOR]

Background: Femoral head collapse is the key to the progress of osteonecrosis of the femoral head (ONFH), but the causes of collapse are not completely clear. The better understanding of the progress of femoral head collapse will guide the treatment strategy for ONFH patients. The purpose of this study was to evaluate the biomechanical influence of necrosis area on the collapse of the femoral head by finite element analysis.Methods: CT and MRI data from the hip joint of a healthy volunteer were collected to establish a finite element (FE) model of a normal hip. Subsequently, five categories of osteonecrosis FE models were established by using the normal model and computer software according to China-Japan Friendship Hospital (CJFH) classification for ONFH. The CJFH system includes five types based on the size and location of necrosis lesions in the femoral head (type M, C, L1, L2, and L3) and the stage of ONFH. The collapse indices of each model were analyzed by FE method, including the displacement, peak von Mises stress and stress index of the simulated necrotic area as well as the lateral pillar contact area of the femoral head to acetabular.Results: (1) The displacement increments in the simulated necrotic areas of type M, C, L1, L2, and L3 models were 3.75 μm, 8.24 μm, 8.47 μm, 18.42 μm, and 20.44 μm respectively; the peak von Mises stress decrements were 1.50 MPa, 3.74 MPa, 3.73 MPa, 4.91 MPa, and 4.92 MPa respectively; and the stress indices were 0.04, 0.08, 0.08, 0.27, and 0.27 respectively. (2) The displacement increments in the lateral pillar contact areas of five type models were significantly different (P < 0.001) and increased in sequence as follows: 1.93 ± 0.15 μm, 5.74 ± 0.92 μm, 5.84 ± 1.42 μm, 14.50 ± 3.00 μm, and 16.43 ± 3.05 μm. The peak von Mises stress decrements were also significantly different (P < 0.001) and increased in sequence as follows: 0.52 ± 0.30 MPa, 0.55 ± 0.12 MPa, 0.67 ± 0.33 MPa, 4.17 ± 0.59 MPa, and 4.19 ± 0.60 MPa. (3) The collapse indices including the displacement increments and peak von Mises stress decrements of type L2 and L3 models were markedly higher than those of type M, C, and L1 models (P < 0.001).Conclusions: The collapse indices of the femoral heads of type L2 and L3 FE models were significantly higher than those of type M, C, and L1. Different areas of necrosis result in varied impact on the femoral head collapse. [ABSTRACT FROM AUTHOR]

Food-insecure households access food pantries to receive supplemental food, yet limited examination of the relationships of food pantry use or household food insecurity with diet quality and health has been documented among food pantry users. This study investigated the associations among food pantry use, household food security, body mass index, self-reported chronic disease and related conditions, and diet quality among food pantry users. Food pantry users in central Indiana were recruited for this cross-sectional study and surveyed for sociodemographic characteristics, food pantry use frequency, household food security, diet quality, and chronic disease and related conditions. Measurements of height and weight were obtained. Data from 270 participants, aged 21 to 80 years, were collected from June 2014 to December 2015. Healthy Eating Index-2010 (HEI-2010) total score, component scores, and body mass index were analyzed across food pantry use and household food security groups using multiple linear regression. Odds of reporting chronic disease and related conditions were compared across food pantry use and household food security groups using logistic regression. Visiting food pantries more than once a month was associated with higher HEI-2010 total score (P =0.03) and Total Protein Foods score (P =0.05) than visiting less often. HEI-2010 scores were not significantly different across household food security groups. Body mass index was not different across food pantry use groups or household food security groups. Household food insecurity was associated with higher odds of reporting heart disease (age- and sex-adjusted odds ratio=2.65; 95% CI, 1.05-6.69) compared with household food security. Food pantry use frequency differentiates diet quality, and household food security status differentiates chronic disease and related conditions among low-resource food pantry user subpopulations. [ABSTRACT FROM AUTHOR]

• Dislocation is recognized as the starting point for thermal decomposition. • The thermal etching morphology is determined by the type of dislocation. • A new method to measure the dislocation density in GaN is provided. • Dislocation has a great influence on the thermostability of GaN. The thermal annealing process is widely used in the growth and subsequent process of GaN, but the mechanism of thermal decomposition is unclear. A series of GaN templates were annealed at 1040 °C for different time. It is found that dislocations play an important role in both the origin of thermal decomposition and the evolution of surface morphology. The thermal decomposition rate of GaN without dislocations is much lower than that with dislocations. Thermal annealing could be used as a new method to assess the dislocation density of GaN. This study provides the underlying insights needed to study the thermostability of intrinsic GaN. [ABSTRACT FROM AUTHOR]

• Quantifying the uncertainty of wind power through the use of CVaR and its admissible range, which allows for the direct consideration of wind power uncertainty within the IES UC model. • Developing an IES UC model that accounts for the CVaR of wind power, with the objective of minimizing the sum of the total system operating cost and the CVaR of wind power. • Solving the nonlinear components of CVaR through piecewise linear approximation and handling the flow constraints of the natural gas pipeline using an incremental linearization method, resulting in the transformation of the proposed model into a MILP problem. To address the formidable challenges posed by wind power grid connection and minimize the operational risks arising from wind power fluctuations, this paper proposes an IES-UC optimization model that incorporates power-to-Gas (P2G) and wind power conditional value at risk (CVaR). To start, the uncertainty of wind power is analyzed through the application of CVaR theory, while P2G methods are employed to reduce wind power curtailment and power storage devices are utilized to mitigate the operational risks due to wind power fluctuations. Next, to adequately exploit the flexibility inherent in the gas-thermal dynamic process and enhance the system's flexibility and wind power accommodation capacity, the dynamic transmission equations of the gas and thermal networks are derived through a thorough examination of the dynamics of the gas-thermal network. Finally, to increase computational efficiency, the nonlinear integral term of the CVaR model is linearized via piecewise linearization, transforming the model into a mixed integer linear programming (MILP) problem. The validity and feasibility of the proposed model have been demonstrated through simulations on 6–6–8 and 118–20–16 test systems. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The methanol gas sensing property of the nitrogen-doped quantum dot/Ag-LaFeO 3 p-n heterojunction materials (NALPN) are advanced and the experimental findings are innovative. • The response of NALPN sensor to 5 ppm methanol is 73 and the maximum response to other gases is 5 at 92°C. • The gas sensitivity test results show NALPN is a good gas-sensitive material with high response, low operating temperature and good selectivity to 5 ppm methanol gas. Abstract The unique electronic properties (electron mobility and carrier lifetime) are key factors for metal oxide semiconductor devices that directly determine the device's performance and application. Electron mobility of metal oxide semiconductor has a certain impact on response and operating temperature of gas sensor. Heterojunction composites of carbon quantum dots (CQDs) and perovskite materials have attracted much attention due to their great potential for gas sensors. In this paper, a gas sensor for monitoring methanol gas was developed based on nitrogen-doped carbon quantum dot/Ag-LaFeO 3 (NCQDs/Ag-LaFeO 3) p-n heterojunction materials (NALPN). NCQDS and Ag-LaFeO 3 form a heterojunction, which improves the carrier transport ability and separation of electron-hole pairs. The surface of NCQDs contains COOH, optimize the selectivity of Ag-LaFeO 3 to methanol gas. Gas sensitivity test results show that the NALPN to 5 ppm methanol gas possessed high response (73), low operating temperature (92 °C) and good selectivity. These excellent properties prove that NALPN materials are the main competitors for future gas sensitive materials. [ABSTRACT FROM AUTHOR]

Highlights • Acoustic reactance of shunted diaphragm can be tuned for broadband absorption. • Shunt circuit introduces negative acoustic mass and stiffness. • Positive acoustic mass and stiffness of the diaphragm can be canceled in broadband. • A design procedure is proposed for uniform sound absorption over a broadband. • Experimental results agree with theoretical predictions. Abstract Recent study shows that a suspended diaphragm may function as an efficient sound absorbing device if a properly designed shunt electrical circuit is connected. The sound absorption performance mostly depends on the acoustic impedance of the suspended diaphragm, which is strongly coupled to the electrical impedance of the shunt circuit via the electromechanical coupling induced by a moving-coil in a DC magnetic field. This study concerns tuning the acoustic impedance of the diaphragm with shunt electrical circuit, or a 'shunted-electromechanical-diaphragm' (SEMD). A lumped parameter model is used to analyze the effect of each circuit element on the acoustic impedance of the SEMD. Results show that sound absorption coefficients of the SEMD can be adjusted at low, middle and high frequencies by tuning the capacitance, resistance and inductance of the circuit, respectively. Further analyses show that the shunt circuit introduces negative acoustic mass and reactance at middle frequencies, which can be used to cancel the acoustic mass and stiffness of the diaphragm, resulting in a vanishing reactance of the diaphragm in a broad frequency band. By tuning the resistance of the circuit to modify the acoustic resistance of the SEMD, the sound absorption coefficient of the SEMD can be adjusted to any specific level. A prototype SEMD is tested with different sets of circuit parameters using an acoustic impedance tube. Agreement is observed between the experimental results and theoretical predictions. [ABSTRACT FROM AUTHOR]

• An improved equation between principal stresses and TOF variations is confirmed. • The longitudinal wave velocities of CFRP composite at seven angles are measured. • The stress-acoustic coefficients of CFRP composite are determined. • The acoustoelastic coefficients of CFRP are compared with the reference values. Stress measurement in anisotropic materials attracted considerable interest from the field of engineering. This study presents an improved ultrasonic method for measuring plane stresses in orthotropic materials. This study considers the velocity variations of critically refracted longitudinal (LCR) waves induced by orthotropic anisotropy and internal stresses. The stress–acoustic relation in orthotropic materials is used as theoretical basis for the proposed ultrasonic method. To verify the accuracy and usability of these relations, measurements are performed on a 6061 aluminum alloy and a carbon fiber reinforced plastic (CFRP) composite are subjected to under tensile tests. As preconditions for testing, longitudinal wave velocity is measured and LCR wave wedges are designed for these two materials. Stress–acoustic coefficients are determined by a series of calibration tests. Finally, we confirm the accuracy of this method by comparing the acoustoelastic coefficients of the 6061 aluminum alloy with certain reference values. The acoustoelastic coefficients of CFRP composite are compared with the theoretically predicted curve to assess its usability for orthotropic materials. [ABSTRACT FROM AUTHOR]

To reduce the conservativeness of robust optimization-based unit commitment methods, an uncertainty set is usually prespecified with respect to the distributions of uncertain renewable resources, i.e., wind power. However, since the law of large numbers does not always work in practice, the obtained probability distribution may be unreliable. In this paper, a data-driven adaptive robust optimization method for the unit commitment of bulk power systems with high-level wind power integration is proposed. Different from the conventional robust unit commitment methods, the distributional uncertainty of wind power is well respected in the proposed approach. An imprecise-Dirichlet-model-based method is developed to construct the ambiguity set of wind power, which incorporates all possible probability distributions confirmed by historical data. The set can dynamically change with the data, i.e., the more valid data we have, the smaller the ambiguity set will become. With respect to the bounds of the ambiguity set, a polyhedron uncertainty set of wind power is constructed. By tuning the parameters of the uncertainty set, a balance between operational efficiency and risk can be achieved. An adaptive, robust unit commitment model is constructed based on the uncertainty set. By using the duality principle and big-M method, the formulations are converted into a mixed integer linear programming problem and solved using a column and constraint generation algorithm. Case studies on two benchmark systems illustrate the effectiveness and efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ag-LaFeO 3 based gas sensor using molecular imprinting technique has been successfully applied to the detection of xylene. • Ultrahigh response (resistance ratio = 36.2) to 5 ppm xylene is achieved. • The optimal operating temperature (99 °C) is extremely low. Abstract Xylene is a hazardous volatile organic compound, however, the selective detection of ppm-level xylene using oxide semiconductor gas sensor remains a challenging issue. In this study, Ag-LaFeO 3 was modified with molecular imprinting technique, in which methacrylic acid and hydroxyethyl methylacrylate are used as functional monomers, respectively. Based on XRD, EDS, XPS, SEM, TEM, BET nitrogen adsorption observations, the structure and morphology of the samples are characterized. The as-prepared molecularly imprinted nanoparticles with methacrylic acid as functional monomer exhibit high selectivity and response to xylene gas, and the response is dependent on the type and content of the functional monomer. To 5 ppm xylene, the optimal response is 36.2 at the operating temperature of 99 °C. In addition, low cross-responses to the other test gases were observed. The remarkable enhancement in the gas-sensing properties of the samples is attributed to their high specific surface area and molecular imprinting structure. [ABSTRACT FROM AUTHOR]

The increasingly high integration of wind power into power systems will further increase the power uncertainty and make it difficult to calculate the requirement of the reserve. In this article, a risk-based reserve optimization approach is proposed to quantitatively evaluate the reserve requirement of a large-scale wind-storage system. Conditional value-at risk (CVaR) is adapted to calculate the risk reserve managing the uncertainty of wind generation; this risk reserve achieves the optimal risk without sacrificing system reliability. An energy storage system (ESS) is employed to undertake the role of reserve transfer (RT) by cooperating with wind generation and conventional thermal units in the decision-making of unit commitment (UC); their cooperation and coordination can be achieved by building a bilevel optimization model with a day-ahead risk-constrained unit commitment model and a real-time risk reserve adjustment model. By using the duality principle and the big-M method, the formulations are converted into a mixed integer linear programing problem (MILP) that is solved using a column and constraint generation algorithm (C&CG). The model is tested on the six-bus system and the IEEE 118-bus system. The simulation results show that the ESS can transfer the reserve capacity of the thermal generator and improve the ability to accommodate the uncertainty of wind power generation, thereby demonstrating the effectiveness of the proposed methodology. [ABSTRACT FROM AUTHOR]

We performed the adsorption of NO 2 on transition metal (TM) doped InN monolayer by using density functional theory (DFT). Firstly, adsorption of four kinds of TM atom (Pd, Pt, Ag, Au) on pristine InN monolayer was explored including four different adsorption sites (T In , T N , B In-N and H). Then, for NO 2 adsorption, by calculating adsorption energy, adsorption distance, charge transfer, magnetic moment and density of states, the chemical interactions between NO 2 and TM doped InN monolayer (TM-InN) were discussed. We have gotten the following results: (1) Pd, Pt, Ag, Au atoms are all likely to be adsorbed on T N site with exothermal process; (2) Pt and Au gain electrons while Pd and Ag lost electrons and Ag and Au can introduce magnetic moment to InN monolayer; (3) NO 2 can be chemi-adsorbed on TM atom modified InN monolayer due to the considerable adsorption energy and charge transfer; (4) NO 2 molecule orbitals experience significant changes after adsorption. This study can provide prospects and possible application value for TM-InN to be a potential material to adsorb and detect NO 2 . [ABSTRACT FROM AUTHOR]

P-type Ag-LaFeO 3 (AL) is a promising gas-sensing material owing to its large surface area, rich active oxygen lattice, good thermostability, controllable structure and strong reducibility. While the operating temperature of which is high. In this study, B, N, S and Cl doped graphene quantum dots (GQD) were prepared with a simple liquid-phase exfoliation method and with which decorated AL in order to low the operating temperature of AL. The sensors based on the doped GQD operated at room temperature and showed affinity toward different volatile organic compounds (VOCs). B-GQD revealed p-type semiconductor property and reduced the operating temperature of AL markedly form 90 °C to 55 °C when composite with it because of the synergy effect. Undoped GQD and N, S, Cl doped GQD showed n-type semiconductor property and oppositely increased the operating temperature of AL to different extent when composite with AL. That is, the more electrons in the outer layer of the doped element, the higher the temperature of GQD/AL composite rise. Thus the gas-sensing properties of B-GQD/AL composite was further researched, the results showed that the composite possessed high sensitivity, good selectivity, good stability and low operating temperature to low concentration of formaldehyde. [ABSTRACT FROM AUTHOR]

[Display omitted] Fano resonance with a sharp and ultra-narrow asymmetrical spectral profile is formed by interfering a background mode by a local mode, which is widely found in numerous physical areas and serves as a bedrock for architecting functional metamaterials and constructing selective filters for physical waves. However, it requires subtle geometries and accurate mechanical properties for generating a local resonance to realize Fano resonance at a desired frequency, which challenges its widely applications. Here, we report an electromechanical Fano resonance delivered by an electromechanical diaphragm shunted by a multiple-branch resonant circuit (SEMD). The local resonance of the SEMD is induced by the electrical circuit, which removes the constraints of subtle geometries and mechanical properties design and allows digitally programing the Fano resonance through coding MOSFET switches to select a preset circuit branch. A Lumped theoretical model is used to analyze circuit effects, with verification by experiments in a one-dimensional waveguide, showing programing of three key parameters, the frequency, Q factor and extinction ratio (ER), of the electromechanical Fano resonance. The frequency of perfect sound absorption (null reflection) digitally assigned in a frequency range of [158.5 Hz 1486.75 Hz] is experimentally demonstrated, equivalent to a wavelength-to-thickness ratio range of [31.6 0.30], regarding the equivalent thickness of the SEMD. The Q factor of the SEMD, indexing the selectivity, can be tuned up to 145 in experiments and over 6000 theoretically, giving the half-bandwidth less than 0.2 Hz. The extinction ratio (ER) reaches 30 dB in experiments whereas 60 dB in predictions which means the circuit can totally change the acoustic response of the mechanical diaphragm. Due to features of real-time programmability, broadband tunability and mechanical properties and geometries independence, the SEMD with an electromechanical Fano resonance would be a superior platform to fulfill the envisaged manipulation of acoustics waves in a digital manner. [ABSTRACT FROM AUTHOR]

Surface modifications are efficient techniques to enhance the corrosion resistance of flaky carbonyl iron (FCI) for electromagnetic wave absorbing coatings. However, with the emergence of diverse harsh service environments (tropical marine climate, etc.), it becomes more challenging for traditional single-layer modification of FCI to meet the durability requirements. Here, a facile synthesis method for enhancing the corrosion resistance of FCI was developed by dual silane surface modifications. The corrosion behaviors of FCI with and without dual silane surface modifications were investigated by immersing in a corrosive environment (chemical corrosion) and electrochemical testing. Following immersion tests, the dual layer modified FCI exhibits the highest remaining solid mass, the highest self-corrosion potential, the largest polarization resistance, and the lowest corrosion current density. In addition, the dual layer modified FCI maintains a decent electromagnetic wave absorption ability which reaches the minimum value of the reflection loss ( RL min ) of − 21 dB with a thickness of 3 mm. Therefore, designing a dual coated structure provides a promising scalable strategy to enhance the applicability of electromagnetic wave absorption coating during service in diverse field conditions. [ABSTRACT FROM AUTHOR]

To explore the distribution and evolution of the surrounding rock of underground caverns of hydropower stations, the dynamic compression tests for granite sample were carried out and the dynamic constitutive relation suitable to computer programming was established in terms of strain-based static elastic-plastic damage constitutive relation. By inputting five earthquakes of various frequency spectra, the fully nonlinear dynamic analysis was performed for some large underground caverns in the gorge and mountain region in Sichuan Province in China with the explicit difference method. The simulation results show that, as the input seismic waves become strong gradually, the damage zone generally extends deeply from the middle of side walls. The damage zone reaches the maximum value in areas immediately after the seismic acceleration peak arrives and keeps constant thereafter. According to the initial analysis, if the dominant frequency of input wave approaches the natural frequency of underground caverns, the maximum area of damage zone will increase. Those findings may provide practical data for earthquake-resistant design and construction. [ABSTRACT FROM AUTHOR]

Aging is closely associated with osteoarthritis (OA). Although its underlying mechanisms remain unknown, cellular senescence in chondrocytes has become an important therapeutic target for the treatment of OA. Cysteinyl leukotriene receptors (cysLTRs) mediate the pathobiological function of cysteinyl leukotrienes (cysLTs). However, the roles of cysLTRs in the pathogenesis of OA have not been reported before. In the current study, we found that cysLTR1 but not cysLTR2 is expressed in human primary chondrocytes. In addition, stimulation with tumor necrosis factor α (TNF-α) resulted in a significant increase in the expression of cysLTR1. Interestingly, montelukast, a specific cysLTR1 antagonist, attenuated TNF-α-induced up-regulation of the activity of senescence-associated β-galactosidase (SA-β-Gal). In addition, TNF-α led to cell cycle arrest at the G0/G1 phase, which was prevented by treatment with montelukast. Notably, montelukast reduced expression of the senescence markers p53, p21 and PAI-1. In addition, montelukast ameliorated TNF-α-induced K382 acetylation of p53 by promoting the expression of SIRT1. Silencing of SIRT1 using SIRT1 siRNA broke the inhibitory effects of montelukast on K382 acetylation of p53. Importantly, silencing of cysLTR1 reversed the reduction of SIRT1 expression as well as the K382 acetylation of p53. Our findings strongly implicate that cysLTR1 has the capacity to regulate cellular senescence in chondrocytes. It is suggested that montelukast may be a potential therapeutic agent for chondro-protective therapy. [ABSTRACT FROM AUTHOR]

In virtue of abundant sodium resources, sodium ion batteries (SIBs) have been regarded as one of the most promising alternatives for large-scale energy storage applications. However, the absence of a suitable anode material makes it difficult to realize these applications. Here, we demonstrate an effective synthesis strategy of using a “microreactor” consisting of melamine fiber (inside) and graphene oxide (GO, outside) to fabricate three dimensional (3D) nitrogen doped (N-doped) graphene as high-performance anode materials for sodium ion batteries. Through a controlled pyrolysis, the inside melamine fiber and the outside GO layer has been converted into N-doped graphene and reduced graphene oxide ( r -GO) respectively, and thus the “microreactor” is transformed into interconnected 3D N-doped graphene structures. Such highly desired 3D graphene structures show reversible sodium storage capacities up to ∼305 mA h g −1 after 500 cycles at a current density of 0.2 A g −1 and promising long cycling stability with a stable capacity of ∼198 mA h g −1  at 5 A g −1 after 5000 cycles. The high capacity and superior durability in combination with the facile synthesis procedure of the 3D graphene structure make it a promising anode material for SIBs and other energy storage applications. [ABSTRACT FROM AUTHOR]

Based on a kind of sintered hydroxyapatite (HA) with a good cytocompatibility, a series of polylactic acid (PLA) and PLA/HA with the various PLA:HA weight ratio (5:5, 4:6, 3:7, 2:8, 1:9) were fabricated by supercritical CO2. The physical and chemical properties were evaluated by pH, degradation, water absorption, porosity, density, mechanical property, and cytotoxicity respectively. With the increase of HA content, the pH value and porosity increased gradually, while weight loss rate and the density showed a gradual downward trend. Existence of HA can drastically improve the hydroscopicity of PLA scaffolds. The compression strength values slightly increased (p > 0.05) from 39.96 MPa of PLA to 45.00 MPa of PLA/HA with the ratio of 7:3, subsequently, the values decreased (p < 0.05) from 43.29 MPa (8:2) to 19.00 MPa (9:1). While the modulus of elasticity decreased (p < 0.05) from 5.89 to 1.84 GPa with increasing HA content. The PLA/HA (8:2) promoted cell proliferation more significantly than any of other groups (p < 0.05). Based on the results, the overall properties of porous scaffolds are the optimal when the weight ratio of PLA/HA is 8:2. Its pH, porosity, density, compression strength, and elasticity modulus are 7.39, 83.0%, 0.60g/cm-3, 34.1 MPa and 2.63 GPa, respectively. SEM observation presented a homogeneous distribution of HA in PLA matrix and a foam-like structure comprising interconnected pores. [ABSTRACT FROM AUTHOR]

Raffinose family oligosaccharides (RFOs) accumulate in seeds during maturation desiccation in many plant species. However, it remains unclear whether RFOs have a role in establishing seed vigor. GALACTINOL SYNTHASE (GOLS), RAFFINOSE SYNTHASE (RS), and STACHYOSE SYNTHASE (STS) are the enzymes responsible for RFO biosynthesis in plants. Interestingly, only raffinose is detected in maize seeds, and a unique maize RS gene ( ZmRS ) was identified. In this study, we found that two independent mutator ( Mu )-interrupted zmrs lines, containing no raffinose but hyperaccumulating galactinol, have significantly reduced seed vigor, compared with null segregant controls. Unlike maize, Arabidopsis thaliana seeds contain several RFOs (raffinose, stachyose, and verbascose). Manipulation of A. thaliana RFO content by overexpressing ZmGOLS2 , ZmRS , or AtSTS demonstrated that co-overexpression of ZmGOLS2 and ZmRS , or overexpression of ZmGOLS2 alone, significantly increased the total content of RFOs and enhanced Arabidopsis seed vigor. Surprisingly, while overexpression of ZmRS increased seed raffinose content, its overexpression dramatically decreased seed vigor and reduced the seed amounts of galactinol, stachyose, and verbascose. In contrast, the atrs5 mutant seeds are similar to those of the wild type with regard to seed vigor and RFO content, except for stachyose, which accumulated in atrs5 seeds. Total RFOs, RFO/sucrose ratio, but not absolute individual RFO amounts, positively correlated with A. thaliana seed vigor, to which stachyose and verbascose contribute more than raffinose. Taken together, these results provide new insights into regulatory mechanisms of seed vigor and reveal distinct requirement for RFOs in modulating seed vigor in a monocot and a dicot. [ABSTRACT FROM AUTHOR]

The calcineurin B-like (CBL) protein and the CBL-interacting protein kinase (CIPK) signaling pathway play important roles in plant abiotic stress tolerance. To investigate the molecular mechanism of salt stress tolerance of foxtail millet, SiCBL4 and SiCIPK24 were identified and functionally characterized. Both SiCBL4 and SiCIPK24 were induced by salt, abscisic acid (ABA), methyl viologen (MV), and heat shock stress in foxtail millet seedlings. Yeast two-hybrid and bimolecular fluorescence complementation assay showed that SiCBL4 interacted with SiCIPK24. The mutation of the N-myristoylation site of SiCBL4 changed the sub-cellular localization of SiCBL4 and directed the SiCBL4-SiCIPK24 protein complex from plasma membrane to cytoplasm, and disrupted its function in plant salt stress tolerance. Overexpression of SiCBL4 or SiCIPK24 in Arabidopsis sos3-1 or sos2-1 mutant plants rescued the mutant salt hypersensitivity phenotype. In addition, overexpression of SiCIPK24 also enhanced the salt stress tolerance of Arabidopsis wild-type plants. This work helps to understand the structure and function of the foxtail millet CBL and CIPK genes and confirmed that the foxtail millet CBL-CIPK pathway can be manipulated to enhance the plant salt stress tolerance. [ABSTRACT FROM AUTHOR]

Unsteady heat release coupled with pressure fluctuation triggers the thermoacoustic instability which may damage a combustion chamber severely. This study demonstrates an electroacoustic control approach of suppressing the thermoacoustic instability in a Rijke tube by altering the wall boundary condition. An electrically shunted loudspeaker driver device is connected as a side-branch to the main tube via a small aperture. Tests in an impedance tube show that this device has sound absorption coefficient up to 40% under normal incidence from 100 Hz to 400 Hz, namely over two octaves. Experimental result demonstrates that such a broadband acoustic performance can effectively eliminate the Rijke-tube instability from 94 Hz to 378 Hz (when the tube length varies from 1.8 m to 0.9 m, the first mode frequency for the former is 94 Hz and the second mode frequency for the latter is 378 Hz). Theoretical investigation reveals that the devices act as a damper draining out sound energy through a tiny hole to eliminate the instability. Finally, it is also estimated based on the experimental data that small amount of sound energy is actually absorbed when the system undergoes a transition from the unstable to stable state if the contrpaol is activated. When the system is actually stabilized, no sound is radiated so no sound energy needs to be absorbed by the control device. [ABSTRACT FROM AUTHOR]

In order to develop the thermodynamic database containing rare earth sesquioxides (RE 2 O 3 ), accurate thermodynamic descriptions of all stable and metastable RE 2 O 3 phases are required. Rare earth sesquioxides have five polymorphs, which are (from low to high temperature) the cubic phase (C), the monoclinic phase (B), the hexagonal phase (A), the high temperature hexagonal phase (H), and the high temperature cubic phase (X). However, the thermodynamic property data of all polymorphs available in the literature are insufficient. In particular, the thermodynamic data for the phases stable only at high temperatures and for metastable phases are not well investigated. In this study, all ∆ H 298 K o , S 298 K o , C P (or heat content) and phase transition temperature ( T tr ) data available in the literature for each rare earth sesquioxide were collected and critically evaluated based on the sample preparations, experimental procedures and characterization techniques. Relationships between ∆ H 298 K o , S 298 K o , and T tr against the ionic radii of the entire rare earth cations were then established and missing thermodynamic information was predicted based on the general trends. In these ways, the accurate and consistent Gibbs energies of all stable and metastable RE 2 O 3 phases (RE = La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y and Sc) were prepared. These Gibbs energy data can be readily used for the development of a comprehensive thermodynamic database containing rare earth oxides. [ABSTRACT FROM AUTHOR]