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Background: Recently, deep convolutional neural networks (CNNs) have been widely adopted for ultrasound sequence tracking and shown to perform satisfactorily. However, existing trackers ignore the rich temporal contexts that exists between consecutive frames, making it difficult for these trackers to perceive information about the motion of the target. Purpose: In this paper, we propose a sophisticated method to fully utilize temporal contexts for ultrasound sequences tracking with information bottleneck. This method determines the temporal contexts between consecutive frames to perform both feature extraction and similarity graph refinement, and information bottleneck is integrated into the feature refinement process. Methods: The proposed tracker combined three models. First, online temporal adaptive convolutional neural network (TAdaCNN) is proposed to focus on feature extraction and enhance spatial features using temporal information. Second, information bottleneck (IB) is incorporated to achieve more accurate target tracking by maximally limiting the amount of information in the network and discarding irrelevant information. Finally, we propose temporal adaptive transformer (TA‐Trans) that efficiently encodes temporal knowledge by decoding it for similarity graph refinement. The tracker was trained on 2015 MICCAI Challenge on Liver Ultrasound Tracking (CLUST) dataset to evaluate the performance of the proposed method by calculating the tracking error (TE) between the predicted landmarks and the ground truth landmarks for each frame. The experimental results are compared with 13 state‐of‐the‐art methods, and ablation studies are conducted. Results: On CLUST 2015 dataset, our proposed model achieves a mean TE of 0.81 ± 0.74 mm and a maximum TE of 1.93 mm for 85 point‐landmarks across 39 ultrasound sequences in the 2D sequences. Tracking speed ranged from 41 to 63 frames per second (fps). Conclusions: This study demonstrates a new integrated workflow for ultrasound sequences motion tracking. The results show that the model has excellent accuracy and robustness. Reliable and accurate motion estimation is provided for applications requiring real‐time motion estimation in the context of ultrasound‐guided radiation therapy. [ABSTRACT FROM AUTHOR]

With the increase of environmental pollution and depletion of fossil fuel resources, the utilization of renewable biomass resources for developing functional materials or fine chemicals is of great value and has attracted considerable attention. Nanocellulose, as a well‐known renewable nanomaterial, is regarded as a promising nano building block for advanced functional materials owing to its unique structure and properties, as well as natural abundance. Typically, its high mechanical strength, structural flexibility, reinforcing capabilities, and tunable self‐assembly behavior makes it highly attractive to fabricate flexible materials for various applications. Herein, the recent progress in the design, properties, and applications of advanced flexible materials from nanocellulose is comprehensively summarized. The preparation and properties of nanocellulose are first briefly introduced and discuss its merits in fabricating flexible materials. Then, various advanced flexible materials from nanocellulose are introduced, and the critical role of nanocellulose in constructing flexible materials is highlighted based on its intrinsic properties. After that, their applications in energy storage, electronics, sensor, biomedical, thermally insulating, photonic devices, etc., are presented. At last, the outlook of the current challenges and future perspectives for developing nanocellulose‐derived flexible materials are discussed. [ABSTRACT FROM AUTHOR]

Bacillus subtilis, as a biocontrol bacterium, possess a variety of biological functions and the capacity to control plant pathogens. Iturin A is a biosurfactant with broad‐spectrum antifungal activity produced by fermentation of B. subtilis. In this study, the dynamic parameters of solid‐state fermentation (SSF) and submerged fermentation (SMF) of Bacillus velezensis ND were compared, and a method for producing iturin A with a yield of 12.46 g/kg utilizing SSF was proposed. It has significant advantages over SMF and has the highest yield of all previously reported studies. B. velezensis ND also contains protease activity, cellulase activity, iron‐carrying activity, the ability to synthesis 3‐indoleacetic acid (IAA), fixation nitrogen, and degrade phosphorus. In cotton pot experiments, it can effectively increase cotton growth and minimize Verticillium wilt. This strain's superior fermentation efficiency, biological function, and biocontrol ability are sufficient to demonstrate its promise for the development and use of biocontrol agents. [ABSTRACT FROM AUTHOR]

In this article, we study anisotropic immersed finite element (AIFE) methods for the elliptic interface system. After establishing the existence and uniqueness of the weak solution, we construct a linear AIFE method for solving the interface system. Different from the scalar problem, the jump conditions for each unknown function are coupled together in the anisotropic problem considered here. Through defining suitable interpolations, we deduce the error estimates in L2‐$$ {L}^2\hbox{-} $$ and H1‐norms$$ {H}^1\hbox{-} \mathrm{norms} $$ for the proposed AIFE method. Moreover, we show some numerical experiments to verify the correction of the theoretical predictions. [ABSTRACT FROM AUTHOR]

Antistatic packaging film plays an important role in protecting sensitive electronic components from the damage of electrostatic discharge (ESD) during transportation and application. Considering the antistatic property and environmental friendliness of polyvinyl alcohol (PVA), PVA was chosen as matrix to prepare PVA/carbon fiber (CF) composite film via melt casting and asynchronous biaxial stretching. The addition of CF made more perfect conductive pathway formed in system, thus improving the electric property of the composite precursor sheet. And the subsequent biaxial stretching further promoted the cross arrangement of CF as well as the orientation of PVA molecular chains, so endowed the stretched composite film with excellent mechanical, antistatic and water‐resistant properties. When CF content was 5 wt% and the stretching ratio was 3.0 × 3.0, the tensile strength, volume resistivity and water contact angle of the composite film reached 69.4 MPa, 1.07 × 105 Ω·cm, and 74.7° respectively, which met the requirements of electrostatic dissipation packaging. This work highlights the structural evolution of PVA/CF composites under biaxial stretching and spurs the devising of antistatic packaging materials. [ABSTRACT FROM AUTHOR]

Poly (vinyl alcohol)/polylactic acid (PVA/PLA) blend film, which is environment friendly and has potential applications in food and electronic packaging fields, was fabricated by melt extrusion casting. Fourier transform infrared spectroscopy analysis confirmed the formation of the hydrogen bonding between PLA and PVA, which improved the compatibility of PLA with PVA, making PLA uniformly dispersed in PVA matrix as small spheres, even when PLA content increase to 15 wt%. In this way, the original hydrogen bond network among PVA was disturbed and the chain mobility of PVA was activated, endowing PVA/PLA blends with lower melt viscosity than bot modified PVA and PLA, and the blend films with the increased crystallinity, mechanical property, and water resistance. Compared with PVA film, the crystallinity, tensile strength and Young's modulus of the blend film with 15 wt% PLA, respectively, increased by 15.1%, 9 and 51 MPa, and the water contact angle enlarged from 23° to 60°. [ABSTRACT FROM AUTHOR]

Large lattice constant Y3Al5O12, Gd3Ga5O12 (GGG), Y3Sc2Ga3O12 (YSGG), Gd3Sc2Ga3O12, Ca0.4Mg0.25Zr0.65Gd2.6Ga4.1O12 (CaMgZr:GGG), and Gd1.17Y1.83Sc2Ga3O12 (GYSGG) substrate crystals with 2 in. in diameter are grown by the Czochralski (Cz) method, their physical, chemical, and optical properties are analyzed and compared in details. The X‐ray rocking curves (XRCs) illustrate that the as‐grown crystals possess high crystalline quality. The lattice constants of six crystals are calculated and that of GYSGG can be easily adjusted in the range of 1.2450–1.2565 nm by changing the Gd/Y proportion. The dislocation densities on the (111)‐crystalline face are about 102 cm−2 order of magnitude. The thermal conductivities of six crystals are measured to be 11.72, 8.98, 6.83, 5.45, 4.67, and 4.66 W m−1 K−1, respectively. It is found that the thermal expansion coefficients of six crystals can be reduced by annealing at 1273 K for 60 h. In addition, the transmission spectra show that the six crystals have excellent transparency and the coefficients of the Sellmeier equation are fitted by the calculated refractive indices. These results of the six crystals can provide the necessary parameters and references for the selection of suitable substrate materials or laser host crystals. [ABSTRACT FROM AUTHOR]

We apply sensitivity of executive compensation to firm performance as an effective measurement of corporate governance to examine the bonding mechanism among the cross‐listed Chinese firms between 2005 and 2017. Our sample covers the nonfinancial firms listed on both China and Hong Kong stock exchanges (AH‐share firms) and firms in China only (A‐share firms). We find that AH‐share firms have much higher sensitivity of executive compensation to firm performance than A‐share firms. However, the bonding effect only exists when executive cash compensation and firm accounting performance are considered. Executive compensation on stock return, chief executive officer turnover on firm accounting performance, or chief executive officer turnover on stock market performance, all demonstrate no bonding effect. The results are attributed to institutional environment in which executive compensation is solely dependent on accounting profits among Chinese firms, and the A‐share market offers weak investor protection. We also find that both legal and reputational bonding effects work on improved governance of AH‐share firms, although such effects are highly dependent on specific market mechanisms including that of firm executives. Our findings may contribute to current bonding literature and have policy implications on future state‐owned enterprise reforms. [ABSTRACT FROM AUTHOR]

Wind erosion of aeolian sandy soil can cause serious land degradation and other environmental problems, and thus its prevention and control is very important. However, there has not been a very effective way to prevent this severe wind erosion until now, and traditional measures such as mechanical methods, chemical sand‐fixing methods, and agronomic methods also have many disadvantages. The main objective of this study is to evaluate feasibility of microbially induced calcite precipitation (MICP) as a novel soil‐strengthening technique, to cement aeolian sandy soil, and reduce wind erosion risk. For this purpose, aeolian sandy soil was cemented with Sporosarcina pasteurii through MICP technique, and the physical and mechanical properties and wind erosion resistance of cemented aeolian sandy soil were tested. The results show that wind erosion resistance of aeolian sandy soil can be effectively improved by spraying S. pasteurii solution and cementing solution (equal concentration of urea and calcium chloride mixture) into it from the surface, and the cemented aeolian sandy soil had good wind erosion resistance. Finally, morphology of precipitated CaCO3 crystals was studied using scanning electron microscope, optical microscope, and X‐ray diffraction. The calcium carbonate crystals produced in aeolian sandy soil were calcite, and the calcium carbonate crystals had polyhedral, spherical, or flower clusters crystal morphology. The results of this study demonstrate an effective way to use MICP technology to cement aeolian sandy soil and prevent wind erosion, and provide a new way for wind erosion prevention. [ABSTRACT FROM AUTHOR]

Decabromodiphenyl ether (BDE-209) has been detected in human serum, semen, placenta, cord blood and milk worldwide. However, little is known regarding the potential effects on the early human embryonic development of BDE-209. In this study, human embryonic stem cell lines FY-hES-10 and FY-hES-26 were used to evaluate the potential effects and explore the toxification mechanisms using low-level BDE-209 exposure. Our data showed that BDE-209 exposure (1, 10 and 100 nM) reduced the expression of pluripotent genes such as OCT4, SOX2 and NANOG and induced human embryonic stem cells (hESCs) apoptosis. The downregulation of BIRC5/BCL2 and upregulation of BAX were related to apoptosis of hESCs induced by BDE-209 exposure. A mechanism study showed that OCT4 down-regulation accompanied by OCT4 promoter hypermethylation and increasing miR-145/miR-335 levels, OCT4 inhibitors. Moreover, BDE-209 could increase the generation of intracellular reactive oxygen species (ROS) and decrease SOD2 expression. The ROS increase and OCT4 downregulation after BDE-209 exposure could be reversed partly by antioxidant N-acetylcysteine supplement. These findings showed that BDE-209 exposure could decrease pluripotent genes expression via epigenetic regulation and induce apoptosis through ROS generation in human embryonic stem cells in vitro. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Stirling engine has drawn new attention for its high efficiency and flexibility towards the application of different heat sources. A new Stirling engine application in a renewable energy combined heat and power (CHP) concept will be presented, in which powders are used as the heat carrier between the hot storage and the ultimate Stirling reuse. A fluidized bed of small particles (50-150 μm) is examined in this study. The outside heat transfer coefficient to the finned Stirling heat exchanger largely exceeds 1500 W m−2 K−1 at very low fluidization velocities, which is, therefore, not the heat transfer limitation. Positron emission particle tracking experiments demonstrated that the particle movement and mixing in the fluidized bed are not hampered by the presence of the finned heat transfer tube. As the Stirling engine can reach efficiencies in excess of 30 % and has the potential to be integrated in a CHP mode of operation, it should be considered as a hot research topic in the renewable energy sector. [ABSTRACT FROM AUTHOR]

Matching the power supply with demand is a key issue for the development of renewable energy sources: the intermittence of wind or solar power can be overcome by integrating an energy storage system. In comparison with sensible and latent heat storage, thermochemical heat storage has the advantages of both a high energy density, so that reaction products can be stored at ambient temperature for later reuse, and a flexibility of transportation when off-site use is required. An initial thermodynamic and kinetic screening of thermochemical reactions in the temperature range of about 600 to 1200 K is presented. Thermodynamics and kinetics are used to characterize the reactions through the equilibrium temperature, the heat of reaction, the reaction rates, and recovery work. These aspects were studied theoretically and experimentally. The analysis defines the essential design parameters and provides guidance for the important assessment criteria of new candidate reaction systems. [ABSTRACT FROM AUTHOR]

Aspergillus flavus produces potent mutagenic and carcinogenic polyketidederived secondary metabolites known as aflatoxins. Development of host plant resistance in peanut and other crops is the most environmentally friendly and cost-effective method to eliminate the serious problem of aflatoxin contamination in grains. To confirm that putative peanut genes identified in a previous microarray study were involved in peanut resistance to A. flavus infection, 14 genes were selected for further investigation through real-time PCR. The results revealed diverse patterns of gene expression during seed germination after A. flavus inoculation. Based on the expression levels and the relative-expression patterns over a 7-day period, the 14 host genes could be classified into six different groups belonging to three main biochemical and genetic defence processes of lipid metabolism, oxidative signalling and cell-wall synthesis during counterattack. A network of gene expression patterns was activated in sequential order in response to A. flavus invasion in both resistant and susceptible peanut lines during seed germination. Understanding gene expression patterns in peanut will be useful to breeders and other scientists interested in incorporating genetic resources of resistance against A. flavus into peanut germplasm and/or commercial cultivars via conventional and/or molecular methods. [ABSTRACT FROM AUTHOR]

ABSTRACT Acetaminophen, also called paracetamol, is found in Tylenol, Excedrin and other products as over-the-counter medicines. In this study, acetaminophen as a luminol signal enhancer was used in the chemiluminescence (CL) substrate solution of horseradish peroxidase (HRP) for the first time. The use of acetaminophen in the luminol-HRP-H2O2 system affected not only the intensity of the obtained signal, but also its kinetics. It was shown that acetaminophen was to be a potent enhancer of the luminol-HRP-H2O2 system. A putative enhancement mechanism for the luminol-H2O2-HRP-acetaminophen system is presented. The resonance of the nucleophilic amide group and the benzene ring of acetaminophen structure have a great effect on O-H bond dissociation energy of the phenol group and therefore on phenoxyl radical stabilization. These radicals act as mediators between HRP and luminol in an electron transfer reaction that generates luminol radicals and subsequently light emission, in which the intensity of CL is enhanced in the presence of acetaminophen. In addition, a simple method was developed to detect acetaminophen by static injection CL based on the enhanced CL system of luminol-H2O2-HRP by acetaminophen. Experimental conditions, such as pH and concentrations of substrates, have been examined and optimized. The proposed method exhibited good performance, the linear range was from 0.30 to 7.5 mM, the relative standard deviation was 1.86% ( n = 10), limit of detection was 0.16 mM and recovery was 99 ± 4%. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In the work presented here, well-dispersed ferric giniite microcrystals with controlled sizes and shapes are solvothermally synthesized from ionic-liquid precursors by using 1- n-butyl-3-methylimidazolium dihydrogenphosphate ([Bmim][H2PO4]) as phosphate source. The success of this synthesis relies on the concentration and composition of the ionic-liquid precursors. By adjusting the molar ratios of Fe(NO3)3 ⋅9H2O to [Bmim][H2PO4] as well as the composition of ionic-liquid precursors, we obtained uniform microstructures such as bipyramids exposing {111} facets, plates exposing {001} facets, hollow spheres, tetragonal hexadecahedron exposing {441} and {111} facets, and truncated bipyamids with carved {001} facets. The crystalline structure of the ferric giniite microcrystals is disclosed by various characterization techniques. It was revealed that [Bmim][H2PO4] played an important role in stabilizing the {111} facets of ferric giniite crystals, leading to the different morphologies in the presence of ionic-liquid precursors with different compositions. Furthermore, since these ferric giniite crystals were characterized by different facets, they could serve as model Fenton-like catalysts to uncover the correlation between the surface and the catalytic performance for the photodegradation of organic dyes under visible-light irradiation. Our measurements indicate that the photocatalytic activity of as-prepared Fenton-like catalysts is highly dependent on the exposed facets, and the surface area has essentially no obvious effect on the photocatalytic degradation of organic dyes in the present study. It is highly expected that these findings are useful in understanding the photocatalytic activity of Fenton-like catalysts with different morphologies, and suggest a promising new strategy for crystal-facet engineering of photocatalysts for wastewater treatment based on heterogeneous Fenton-like process. [ABSTRACT FROM AUTHOR]

Background Heart failure with preserved ejection fraction (HFpEF) accounts for 50% of patients with heart failure. Clinically, HFpEF prevalence shows age and gender biases. Although the majority of patients with HFpEF are elderly, there is an emergence of young patients with HFpEF. A better understanding of the underlying pathogenic mechanism is urgently needed. Here, we aimed to determine the role of aging in the pathogenesis of HFpEF. Methods and Results HFpEF dietary regimen (high-fat diet + Nω-Nitro-L-arginine methyl ester hydrochloride) was used to induce HFpEF in wild type and telomerase RNA knockout mice (second-generation and third-generation telomerase RNA component knockout), an aging murine model. First, both male and female animals develop HFpEF equally. Second, cardiac wall thickening preceded diastolic dysfunction in all HFpEF animals. Third, accelerated HFpEF onset was observed in second-generation telomerase RNA component knockout (at 6 weeks) and third-generation telomerase RNA component knockout (at 4 weeks) compared with wild type (8 weeks). Fourth, we demonstrate that mitochondrial respiration transitioned from compensatory state (normal basal yet loss of maximal respiratory capacity) to dysfunction (loss of both basal and maximal respiratory capacity) in a p53 dosage dependent manner. Last, using myocardial-specific p53 knockout animals, we demonstrate that loss of p53 activation delays the development of HFpEF. Conclusions Here we demonstrate that p53 activation plays a role in the pathogenesis of HFpEF. We show that short telomere animals exhibit a basal level of p53 activation, mitochondria upregulate mtDNA encoded genes as a mean to compensate for blocked mitochondrial biogenesis, and loss of myocardial p53 delays HFpEF onset in high fat diet + Nω-Nitro-L-arginine methyl ester hydrochloride challenged murine model.