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In this paper, a two-dimensional numerical model for simulating the generation and propagation of tsunami waves caused by upthrust bed movement is developed. To consider the nonlinearity as well as save the computational cost, a Navier–Stokes equation solver is used for the generation zone, and a Serre equation solver is adopted for the downstream evolution of the tsunami waves. The solution of the Navier–Stokes equation solver is extracted and transferred as the initial solution of the Serre solver, which means a one-way coupling is achieved. In this way, a one-way coupled Navier–Stokes-Serre model is obtained. After a detailed validation of the individual solvers, the coupled model is utilized for simulating the generation and propagation of tsunami waves caused by the upthrust bed movement in shallow water of uniform depth. It is found that the coupled model is comparable to the traditional Boussinesq equation model. Finally, the capacity of the coupled model for simulating wave-breaking cases is demonstrated. [ABSTRACT FROM AUTHOR]

Selective carrier energy filtering effect is an important strategy to promote the power factor of a thermoelectrical materials, which requires an appropriate potential barrier and coherent interfaces between the secondary phase and the host matrix. Although the energy filtering effect has been realized in various bulk systems, its efficiency in promoting their thermoelectric performance is limited. Herein, simultaneously increased electrical conductivity and Seebeck coefficient are investigated in Ag-doped Bi 0.5 Sb 1.5 Te 3 films, leading to an increasement of the power factor up to 700%. Microstructure analysis reveals that the thin films prepared from magnetron sputtering consist of highly uniform nanocrystal domains, which construct coherent interfaces somewhere. Moreover, the local Ag doping might depress the Fermi level, providing the possibility to form a suitable potential barrier between the adjacent nanograins. This study suggests a facile method to significantly enhance the thermoelectric performance via energy filtering effect in high quality thin films. [ABSTRACT FROM AUTHOR]

In this paper, we study the multidimensional lattice Schrödinger operators with C 2 -cosine like quasi-periodic (QP) potential. We establish quantitative Green's function estimates, the arithmetic version of Anderson (and dynamical) localization, and the finite volume version of (1 2 -) -Hölder continuity of the integrated density of states for such QP Schrödinger operators. Our proof is based on an extension of the fundamental multi-scale analysis type method of Fröhlich–Spencer–Wittwer (Commun Math Phys 132(1), 5–25, 1990) to the higher lattice dimensions. We resolve the level crossing issue on eigenvalues parameterizations in the case of both higher lattice dimension and C 2 regular potential. [ABSTRACT FROM AUTHOR]

Through whole-genome bisulfite sequencing and RNA-seq, we determined the potential impact of autophagy in regulating DNA methylation in Arabidopsis, providing a solid foundation for further understanding the molecular mechanism of autophagy and how plants cope with nitrogen deficiency. A total of 335 notable differentially expressed genes (DEGs) were discovered in wild-type Arabidopsis (Col-0-N) and an autophagic mutant cultivated under nitrogen starvation (atg5-1-N). Among these, 142 DEGs were associated with hypomethylated regions (hypo-DMRs) and were upregulated. This suggests a correlation between DNA demethylation and the ability of Arabidopsis to cope with nitrogen deficiency. Examination of the hypo-DMR-linked upregulated DEGs indicated that the expression of MYB101, an ABA pathway regulator, may be regulated by DNA demethylation and the recruitment of transcription factors (TFs; ERF57, ERF105, ERF48, and ERF111), which may contribute to the growth arrest induced by abscisic acid (ABA). Additionally, we found that DNA methylation might impact the biosynthesis of salicylic acid (SA). The promoter region of ATGH3.12 (PBS3), a key enzyme in SA synthesis, was hypomethylated, combined with overexpression of PBS3 and its potential TF AT3G46070, suggesting that autophagy defects may lead to SA-activated senescence, depending on DNA demethylation. These findings suggest that DNA hypomethylation may impact the mechanism by which Arabidopsis autophagy mutants (atg5-1) respond to nitrogen deficiency, specifically in relation to ABA and SA regulation. Our evaluation of hormone levels verified that these two hormones are significantly enriched under nitrogen deficiency in atg5-1-N compared to Col-0-N. [ABSTRACT FROM AUTHOR]

In this paper we develop a Nash-Moser iteration type reducibility approach to prove the (inverse) localization for some d-dimensional discrete almost-periodic operators with power-law long-range hopping. We also provide a quantitative lower bound on the regularity of the hopping. As an application, some results of Sarnak (Comm Math Phys 84(3):377–401, 1982), Pöschel (Comm Math Phys 88(4):447–463, 1983), Craig (Comm Math Phys 88(1):113–131, 1983) and Bellissard et al. (Comm Math Phys 88(4):465–477, 1983) are generalized to the power-law hopping case. [ABSTRACT FROM AUTHOR]

In this paper we study the lattice quasi-periodic operators with power-law long-range hopping and meromorphic monotone potentials, and diagonalize the operators via a Nash-Moser iteration scheme. As applications, we obtain uniform power-law localization, uniform dynamical localization and Lipschitz continuity of the integrated density of states (IDS) for such operators. Our main motivation comes from investigating quantum suppression of chaos in a quantum kicked rotor model with non-analytical potential. [ABSTRACT FROM AUTHOR]

Metallic glasses with secondary crystalline phase have been reported to either enhance or degrade the global plasticity. Here, we employed molecular dynamics simulation to investigate a generic glass-forming system, in which crystal-glass composites can be obtained via in situ crystallization. Ex situ composite samples were also constructed by embedding perfect crystals into monolithic glasses in order to delineate the precise influences of the composite microstructure. Our simulations demonstrate both toughening and embrittlement effects due to nanocrystallization. The double-edged-sword role of nanocrystals is mainly controlled by elasticity mismatch between the crystalline phase and the glass matrix. The effects of volume fraction and the size of nanocrystals can be understood in the perspective of cumulative probability of shear bands formation and propagation being interfered by the presence of nanocrystals. [ABSTRACT FROM AUTHOR]

In this paper we study discrete quasi-periodic operators with certain long-range hopping and monotonic meromorphic potentials. The hopping amplitude decays with the interparticle distance | n | as e - r log t (1 + | n |) ( t > 1 , r > 0 , n ∈ Z v ). By employing the KAM method, we prove such operators have pure point spectrum with eigenfunctions φ i i ∈ Z v obeying φ i (n) ≤ 2 e - r 2 log t (1 + | n - i |) for all i ∈ Z v , n ∈ Z v . [ABSTRACT FROM AUTHOR]

A hydrothermal method which can convert free cesium ions into stable pollucite at low temperatures was established in this work, avoiding any evaporation pollution during the disposal of cesium containing waste. Meanwhile, rapid synthesis under hydrothermal conditions was achieved using seed guidance, which shorten the growth time of pollucite crystals to 8 h, and making the treatment and disposal of cesium containing wastewater faster. Standard leaching test results show that the leaching rate of Cs was very low (< 3.5 × 10−7 g·m2·d), it still has good thermal stability at a temperature of 1300 °C, when the cesium content in pollucite reaches 20%. [ABSTRACT FROM AUTHOR]

We report a heuristic approach to measure the fracture energy of model metallic glasses using molecular dynamics simulation. Specifically, we adopted the Rivlin-Thomas method, simplified by Suo et al., which is applicable even with the presence of plastic flow. We further modified the testing condition with semi-rigid holders in our molecular simulations, to avoid unintended fracture near the holders. This method was first applied in measuring the fracture energy of a brittle model glass, which agrees well with direct K I C and J I C measurements (both measurements are independent of the crack size). Furthermore, the fracture energy values of a family of model metallic glasses, ranging from brittle to ductile (BTD), were measured. The Poisson's ratio-fracture energy (v-G, or v-G/2γ, normalized by the surface energy) relation obtained here exhibits a BTD transition at a critical Poisson's ratio of 0.31–0.32, consistent with experimental results. [ABSTRACT FROM AUTHOR]

In this work, an attractive malachite leaching agent has been developed for extracting copper from malachite. The possible chemical reaction of malachite in TCA was also analyzed. The effects of the temperature, TCA concentration, average particle size, and stirring speed on malachite dissolution were investigated and a kinetic model was developed to describe the observed effects. It was found that the dissolution rate increases with increasing solution temperature, concentration, and stirring speed, and decreases with increasing mean particle size. The TCA solution can provide H+ ions, which facilitates the dissolution reaction. A surface chemical reaction contraction model controls dissolution and the activation energy of the dissolution process was determined to be 43.23 kJ/mol. It was shown that TCA can be used as a leaching agent for effective extraction of copper from malachite. [ABSTRACT FROM AUTHOR]

The abundance of Proteobacteria and Bacteroidetes in seawater was much higher than that on MPs, while the abundance of Actinobacteria, Firmicutes and Chloroflexi on MPs was significantly higher than in seawater. The results of FTIR showed that polyethylene (PE), polystyrene (PS) and polypropylene (PP) were the main components of experimental MPs originating from fishing nets, foams and woven bulk bags (Fig. In the pathways related to metabolism at level 1, the relative abundance of five metabolic pathways at level 2, including Xenobiotics biodegradation and metabolism, was significantly lower on MPs than in seawater, while the relative abundance of Carbohydrate metabolism on MPs was higher than that in seawater. The clear separation between the confidence ellipse of bacterial communities on various types of MPs and seawater suggested that the composition of bacterial communities on MPs differed significantly from that in seawater. [Extracted from the article]

Under sharp contact loading, glass deforms elastically and then plastically via densification as well as shear flow. Stress build-up during loading, residual stress build-up after unloading, and possible ultimate cracking all depend sensitively on the competition and interplay between densification and shear flow. The crack resistance was shown in experimental studies to generally improve with the increasing contribution of densification in glasses where shear deformation plays a dominant role under indentation. In this work, the role of densification in deformation behaviors of model metallic glasses under sharp contact loading was studied by 3-D nanoindentation tests using indenters with different sharpness in classical molecular dynamics simulations. Starting from a model metallic glass that favors shear deformation, a Lennard-Jones potential was modified to describe model metallic glasses with different abilities of instantaneous densification under compression and permanent densification after decompression. Our studies show that model metallic glass with a higher densification ability under indentation has less stress build-up and less localized shear deformation during loading, as well as smaller residual stress build-up after unloading. However, our study indicates that both instantaneous and permanent densification need to be tuned for designing damage resistant glasses. [ABSTRACT FROM AUTHOR]

• CaCl 2 can enhance markedly the structural strength of self-thickening agent TZXJ network aggregates. • Self-thickening agent TZXJ possesses a strong salt thickening effect and can resist saturated concentration of CaCl 2 solution. The effect of CaCl 2 on the micromorphology of a self-thickening agent (TZXJ) was investigated. This study involved analyzing the compositional changes in acid solutions during acid–rock reactions. It combined dynamic light scattering and viscosity testing to confirm that the presence of CaCl 2 enhances the aggregation strength of the TZXJ network structure in acid solutions. This enhancement is macroscopically evident as an increase in viscosity. Incorporating 10 % CaCl 2 as a promoter into a fresh acid solution, the hydrodynamic radius (Rh) distribution of TZXJ in varying reaction stages was analyzed using dynamic light scattering experiments. The results indicated that the promoter CaCl 2 further strengthens the network association of the TZXJ acid solution, thereby improving its thickening capability. Investigating the viscosity of TZXJ aqueous solutions with varying concentrations of CaCl 2 revealed that TZXJ exhibits notable salt-thickening effects and can withstand saturated CaCl 2 solutions. The microstructural aggregation state and morphology of TZXJ in aqueous solutions were characterized at different CaCl 2 concentrations. Dynamic light scattering results demonstrated an increase in the Rh of TZXJ solutions with CaCl 2 concentrations. In particular, the mean Rh of a 0.8 % TZXJ solution increased from 150.8 nm to 3078.93 nm. Ultraviolet spectral analysis confirmed that the absorption intensity of the TZXJ solutions increased with CaCl 2 concentration, indicating a strengthened network aggregate structure in the TZXJ solutions. Microscopic observations using environmental scanning electron microscopy and transmission electron microscopy revealed that under the influence of calcium chloride, the microstructure of TZXJ transitions from a non-associated, linear carbon chain skeleton to a dense, aggregated network structure. The findings of this study offer theoretical insights for researching polymers resistant to extreme concentrations of CaCl 2. [ABSTRACT FROM AUTHOR]

In this paper we give a multi-scale analysis proof of the power-law localization for random operators on Z d for arbitrary d ≥ 1. [ABSTRACT FROM AUTHOR]

In this paper we study the Schrödinger operator H = - Δ + λ V (x) with a real analytic quasi-periodic potential V (x) defined on R d for arbitrary d ≥ 1 . We prove that H has no eigenvalues in the energy interval - | log λ | C , | log λ | C for every C > 0 if λ > 0 is sufficiently small. The proof is based on the Aubry duality and the multi-scale analysis in the momentum space. [ABSTRACT FROM AUTHOR]

Understanding how nanoparticles deform under compression not only is of scientific importance but also has practical significance in various applications such as tribology, nanoparticle-based probes, and the dry grinding of raw materials. In this study, we conducted compression tests on model brittle glassy nanoparticles using molecular dynamics simulations. We found that during the early stages of plastic deformation, shear bands formed in a similar pattern regardless of the nanoparticle size. However, as the deformation continued, dominant cracks emerged in large nanoparticles while being suppressed in smaller ones. This size-dependent brittle-to-ductile transition can be explained by a simple model based on Griffith's theory. We also investigated the effect of the surface stress state on fracture using thermally tempered nanoparticles. We observed that the presence of compressive surface stress strengthened the nanoparticle by suppressing crack formation, even when a pre-notch was present. On the other hand, tensile surface stress had the opposite effect. Interestingly, nanoparticles with both tensile and compressive surface stress promoted shear deformation, which could potentially compromise the mechanical performance of tempered glass despite delayed crack formation. [ABSTRACT FROM AUTHOR]

Background: Psittacosis, which is also known as parrot fever, is Chlamydia psittaci (C. psittaci) caused infectious disease. The clinical manifestations vary from asymptomatic infection to severe atypical pneumonia or even fatal meningitis. Early recognition of psittacosis is difficult because of its nonspecific clinical manifestations. Culture and gene probe techniques for C. psittaci are not available for routine clinical use, which makes the diagnosis difficult too. Although psittacosis has increasingly been recognized and reported in recent years, cure of severe pneumonia complicated with meningitis, with etiologic diagnosis aided by the use of metagenomic next-generation sequencing (mNGS), is still uncommon. So, it is necessary to report and review such potentially fatal case.Case Presentation: This report describes a 54-year-old woman with C. psittaci caused severe atypical pneumonia and meningitis. She presented with symptoms of fever, dry cough and dyspnea, accompanied by prominent headache. Her condition deteriorated rapidly to respiratory failure and lethargy under the treatment of empirical antibacterial agents, and was treated with invasive mechanical ventilation soon. She denied contact with birds, poultry or horses, but unbiased mNGS of both the bronchoalveolar lavage fluid (BALF) and the cerebrospinal fluid (CSF) identified sequence reads corresponding to C. psittaci infection, and there was no sequence read corresponding to other probable pathogens. Combined use of targeted antimicrobial agents of tetracyclines, macrolides and fluoroquinolones was carried out, and the patient's condition improved and she was discharged home 28 days later. Her status returned close to premorbid condition on day 60 of follow-up.Conclusions: When clinicians come across a patient with atypical pneumonia accompanied by symptoms of meningitis, psittacosis should be taken into consideration. mNGS is a promising detection method in such condition and is recommended. [ABSTRACT FROM AUTHOR]

For the safety assessement of deep geological repository for high-level radioactive waste, radionuclides transport behavior in rock systems is necessary to clairify and establish a suitable model. The advection–dispersion experiments(ADEx) was effectively designed to inadequate transport models through a calibration/validation process, and HTO, selenate (VI) and selenite (IV) migration behavior on crushed granite was studied by a high reliable and dynamic column device to obtailned retardation factor (R) and the dispersion coeffcient (D) by fitting experimental breakthrough curves (BTCs) in a various range of flow rates. Moreover, it showed the similar results between the BTCs of HTO and Se(VI) by fitting a equlibrium model due to no retardation effect. In fact, there was a relatively obvious sorption of Se(IV) in BTCs by fitting a retardation factor (R) value higher than 1. In addition, the two sites non-equilibrium model with a lowest root mean square error were applied to realize Se(IV) sorption mechanism on granite. [ABSTRACT FROM AUTHOR]

[Display omitted] • The pretreatment of chlorine dioxide was developed for cuprite in acid leaching. • The Cu+ on the cuprite surface was effectively oxidized to Cu2+ by chlorine dioxide. • The disproportionation of cuprite in acid leaching was mostly inhibited by pretreatment. • The copper extraction rate of cuprite was greatly improved by oxidation leaching. Cuprite (Cu 2 O) is difficult to directly leach in acidic solutions. In the absence of oxygen, the acidic leaching process of cuprite occurs via a disproportionation reaction and can achieve a maximum cuprite leaching rate of only 50%. Furthermore, to improve the copper leaching rate, Cu(Ι) in cuprite must be oxidized via electrochemical reactions. In this study, chlorine dioxide (ClO 2), a novel environmentally-friendly oxidant, was used to oxidize cuprite to enhance the leaching effect in sulfuric acid (H 2 SO 4) solution. Leaching experiments, electrochemical measurements, atomic force microscopy (AFM), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were used to analyze the oxidation leaching mechanism of cuprite under different reaction conditions. Under the condition of a leaching temperature of 50 °C, sulfuric acid concentration of 0.14 mol/L, average particle size of 60 μm, stirring speed of 800 rpm, and leaching time of 30 min, the leaching rate of cuprite reached 90.18% after adding 0.07 mol/L of ClO 2. Electrochemical measurements demonstrated that a higher ClO 2 concentration increased the corrosion rate of cuprite and oxidation efficiency. Moreover, the surface characterization results showed that with the addition of ClO 2 , monovalent copper on the cuprite surface was oxidized to divalent copper, which promoted the acidic leaching process of cuprite. In addition, once the cuprite surface was oxidized during oxidation leaching, sulfuric acid leached this layer until the end of the leaching process. The DFT calculation results further proved that with the participation of ClO 2 , the leaching reaction of cuprite in an acidic solution was more likely to occur. This oxidation leaching method might provide a reference for the effective leaching of cuprite. [ABSTRACT FROM AUTHOR]

In this paper, we confirm the conjecture of Wang and Zhang (J Stat Phys 134 (5-6):953–968, 2009) in a long time scale, i.e., the displacement of the wavefront for 1D nonlinear random Schrödinger equation is of logarithmic order in time |t|. [ABSTRACT FROM AUTHOR]

BACKGROUND Ara h 1 is a major food allergen in peanuts. Recently, many studies have revealed that the Maillard reaction (MR) affects the allergenicity of food proteins. RESULTS: To investigate the influence of the MR on the allergenicity of Ara h 1, R‐Ara h 1 was processed with glucose in dry heating conditions for different periods. The extent of the MR was assessed by four methods. The changes in secondary and tertiary structures were characterized through spectroscopy assays. Advanced glycation end products (AGE) structures were identified by protein sample dry heating for 60 min, indicating the formation of AGE‐Ara h 1. Simulated gastric fluid (SGF) digestion analysis showed that AGE‐Ara h 1 has higher resistance to peptic digestion than R‐Ara h 1. The BALB/c mouse model was also utilized to explore the effect of the MR on the allergenicity of Ara h 1, and the results showed that the Th2‐type cytokines, antibodies, and histamine content increased, and there was a greater degree of degranulation of rat basophilic leukemia (RBL) cells in the AGE‐Ara h 1 group compared with the R‐Ara h 1 group. CONCLUSION: During the process of dry heating, proteins participated in the MR with changes in secondary and tertiary structures. The condition applying a temperature of 100 °C for 60 min caused the formation of AGE‐Ara h 1. Simulated gastric fluid digestion analysis showed that AGE‐Ara h 1 had a greater resistance to peptic digestion than R‐Ara h 1. The BALB/c mouse model showed that AGE‐Ara h 1 had more allergenicity, indicating that the MR could enhance the allergenicity of Ara h 1. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Feature selection plays a vital role in the detection and discrimination of epileptic seizures in electroencephalogram (EEG) signals. The state-of-the-art EEG classification techniques commonly entail the extraction of the multiple features that would be fed into classifiers. For some techniques, the feature selection strategies have been used to reduce the dimensionality of the entire feature space. However, most of these approaches focus on the performance of classifiers while neglecting the association between the feature and the EEG activity itself. To enhance the inner relationship between the feature subset and the epileptic EEG task with a promising classification accuracy, we propose a machine learning-based pipeline using a novel feature selection algorithm built upon a knockoff filter. First, a number of temporal, spectral, and spatial features are extracted from the raw EEG signals. Second, the proposed feature selection algorithm is exploited to obtain the optimal subgroup of features. Afterwards, three classifiers including k -nearest neighbor (KNN), random forest (RF) and support vector machine (SVM) are used. The experimental results on the Bonn dataset demonstrate that the proposed approach outperforms the state-of-the-art techniques, with accuracy as high as 99.93% for normal and interictal EEG discrimination and 98.95% for interictal and ictal EEG classification. Meanwhile, it has achieved satisfactory sensitivity (95.67% in average), specificity (98.83% in average), and accuracy (98.89% in average) over the Freiburg dataset. [ABSTRACT FROM AUTHOR]

We designed catalytic nanorotors and investigated the rotational motion and energy conversion efficiency using reactive molecular dynamics in two dimensions. First, a two-arm nanorotor was constructed by decorating a slender beam with catalysts asymmetrically on its two long edges, while fixing the beam center as the rotational axis. Autonomous rotation was observed for the two-arm nanorotor immersing in a fuel environment. Here fuel molecules undergo exothermic combination reaction facilitated by the catalysts. It was found that the angular velocity increases with the catalyst coverage parabolically, while the rotary nanomotor efficiency stays roughly constant. These observations are consistent with a single-collision-momentum-transfer-based propulsion model. Furthermore, multi-arm nanorotors (up to eight arms) were constructed by carving radially distributed arms followed by decorating catalysts. For multi-arm nanorotors, both the angular velocity and the efficiency decrease as the number of arms increases. These behaviors contradict the aforementioned model, which are likely due to the deceleration from secondary collisions between products and the nanorotor arms. Our simulation results show that the optimal design for a nanorotor that maximizes its angular velocity and the motor efficiency is a two-arm nanorotor with nearly full coverage of catalysts. [ABSTRACT FROM AUTHOR]

Background: Poor adherence to medication that is taken chronically for the prevention of cardiovascular disease (CVD) continues to occur. Poor adherence is a primary barrier to treatment success and affects not only the patient but also the health care system. Objective: We aim to explore the impacts of risk attitudes and time preferences on the decisions of patients to begin and comply with aspirin therapy for CVD prevention. Methods: Three hundred fifty‐seven patients who used low‐dose aspirin for CVD prevention under the guidance of their doctors completed the survey. The risk attitudes and time preferences of the patients were elicited using a multiple price list experiment. Logistic regression models were used to examine the predictors of adherence to aspirin use. Results: Risk‐seeking behaviours were significantly associated with both nonparticipation (P <.01) and lower compliance (P <.05) in patients. The coefficient for time preference was only significant at the 0.05 level for the decision to initiate aspirin use, which indicated that more impatient patients were less likely to begin with the use of aspirin. Forgetfulness in using aspirin on time and a lack of knowledge (as well as a lack of belief in the use of aspirin) could largely explain the poor adherence to aspirin therapy. Conclusions: The identification of risk seekers and of those individuals who discount the future to a lesser degree may help providers to formulate tailored strategies to their patients, thus effectively enhancing their adherence to treatment. [ABSTRACT FROM AUTHOR]

In this paper, we study the non-self dual extended Harper's model with a Liouvillean frequency. By establishing quantitative reducibility results together with the averaging method, we prove that the lengths of the spectral gaps decay exponentially. [ABSTRACT FROM AUTHOR]

In this paper, we consider the nonlinear elliptic equations on rectangular tori. Using methods in the study of KAM theory and Anderson localization, we prove that these equations admit many analytic solutions. [ABSTRACT FROM AUTHOR]

We report compression-compression fatigue simulations on model metallic-glass nanowires up to a 4% maximum compressive strain and 100 cycles using the molecular dynamics method. The distribution and irreversibility of the fatigue-induced deformations are characterized by the local shear strain and rise of the system temperature, respectively. Furthermore, the system potential energy, structural signatures in terms of icosahedral centers, and radial distribution functions are obtained to identify structural transformations during cyclic loading. No noticeable changes on the aforementioned isotropic structural signatures have been found during fatigue tests. Based on a binary view of the constituting local structures (stable clusters and floppy clusters) in metallic glasses, we attribute the irreversible deformation to inter-conversion of those floppy clusters, which leads to a constant composition of stable and floppy clusters. Finally, uniaxial compression tests were carried out on the cyclically loaded samples. The mechanical behaviors of fatigue-tested samples are rather similar to the original sample. Upon cyclic loading, unlike macroscopic samples, a metallic-glass nanowire is free of permanent structural damage, and therefore does not exhibit deteriorated mechanical behaviors. The excellent fatigue-resistance behavior of a metallic-glass nanowire might be related to its defect-free structure (no stress concentrators). It appears that defects may play a central role in fatigue damages in experimental metallic-glass systems. [ABSTRACT FROM AUTHOR]

The discovery of ferroelectricity in AlN‐based thin films, including Al1‐xScxN and Al1‐xBxN, over the past few years has spurred great research interests worldwide. In this review, we carefully examined the latest developments for these ferroelectric films with respect to alloy composition, temperature, film thickness, deposition condition, and fatigue endurance by electric field cycling. Looking ahead, there is an urgent need to resolve the challenge of large current leakage faced by these films, which necessitates a combined efforts from both simulations and experiments to identify the root cause and eventually come up with engineering strategies to suppress such leakage. In addition, overcoming the thickness scaling challenge to push ferroelectric thin film down to a few nanometers for better device miniaturization will also be of great interest. Considering the somewhat unexpected discovery of AlN‐based thin films with potential ferroelectric application, we believe that it will be also rewarding to further explore other III‐V‐based semiconductor materials. [ABSTRACT FROM AUTHOR]

In this paper, we establish the nonperturbative Anderson localization for a class of one-frequency quasiperiodic block operators with long-range interactions. [ABSTRACT FROM AUTHOR]

Metallic glasses (MGs) are arguably one of the most exciting metallic systems in the past 30 years, attracting significant research effort and undergoing rapid development. Parallel to research on crystalline metals, the sample size has been exploited as property-tuning parameters for MGs. It has been shown that nanometre-sized MG samples exhibit higher-than-bulk elastic limit, tensile strength, and non-zero tensile ductility. While some of the size-related observations have been generally accepted, others have been poorly understood, even hotly debated. Of particular interests is the importance of sample preparation in experiments and model generation in simulations. Here, we will review how the sample size affects mechanical properties including the elastic, plastic, fracture properties, and fatigue endurance, as well as various proposed size-dependent mechanisms and relevant length scales. [ABSTRACT FROM AUTHOR]

BACKGROUND Peanut allergy is one of the most common food allergies worldwide. Studies have shown that the incidence of peanut allergies in Western‐born Asians is higher than that in Asia‐born Asians. Notably, Europeans and Americans mostly eat roasted peanuts, whereas Asians mostly eat boiled or fried peanuts. RESULTS: BALB/c mice were sensitized using purified protein from raw, roasted or boiled peanuts, then fed the same by oral gavage. The relevant allergic reactions were studied using BALB/c mice model, including a rat basophilic leukemia (RBL) cell model, simulated gastric fluid experiments, and ultraviolet (UV) and circular dichroism (CD) spectral analysis. Serological studies showed increased levels of immunoglobulin E, interleukin‐4 and interleukin‐5, and pathological studies showed mast cell degranulation and inflammatory changes in jejunal tissues, with an increase in thymic stromal lymphopoietin (TSLP) gene expression in all treatment groups compared with the control group (phosphate‐buffered saline). Compared with the raw peanut group, sera from the roasted peanut group produced a significant increase in RBL β‐hexosaminidase A release in vitro, and roasted peanuts showed increased resistance to digestion in simulated gastric fluid experiments. Ultraviolet and CD spectral analyses showed that the roasting and boiling processes altered the structure of the major peanut allergens, which may have contributed to the differences observed in peanut allergenicity. CONCLUSION: Our findings indicate that peanut allergies are related to peanut thermal processing methods. In our mouse model, the raw, roasted and boiled peanuts elicited different degrees of allergic response. Compared with raw peanut, roasted peanuts show a higher allergenicity, whereas the boiled peanuts show a lower allergenicity. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Unexpected health-endangering events that lead to an emergency department visit may be perceived as “wake-up calls” and induce significant changes in health-related behavior (“health shock” effect). This study uses two waves of a survey of 826 adults with depression and finds that having an emergency department visit(s) increased medication adherence by 7.6 percentage points (p < 0.05) relative to non-emergency department visitors but had no significant effect on counseling attendance (0.02% points, p = 0.380). Emergency department visits may provide an opportune teachable moment to initiate targeted interventions for positive behavioral change in adults with depression. [ABSTRACT FROM AUTHOR]

Objective: To determine if the release of health care report cards focused on physician practice quality measures leads to changes in consumers' awareness and use of this information.Primary Data Sources: Data from two rounds of a survey of the chronically ill adult population conducted in 14 regions across the United States, combined with longitudinal information from a public reporting tracking database. Both data were collected as part of the evaluation for Aligning Forces for Quality, a nationwide quality improvement initiative funded by the Robert Wood Johnson Foundation.Study Design: Using a longitudinal design and an individual-level fixed effects modeling approach, we estimated the impact of community public reporting efforts, measured by the availability and applicability of physician quality reports, on consumers' awareness and use of physician quality information (PQI).Principal Findings: The baseline level of awareness was 12.6 percent in our study sample, drawn from the general population of chronically ill adults. Among those who were not aware of PQI at the baseline, when PQI became available in their communities for the first time, along with quality measures that are applicable to their specific chronic conditions, the likelihood of PQI awareness increased by 3.8 percentage points. For the same group, we also find similar increases in the uses of PQI linked to newly available physician report cards, although the magnitudes are smaller, between 2 and 3 percentage points.Conclusions: Specific contents of physician report cards can be an important factor in consumers' awareness and use of PQI. Policies to improve awareness and use of PQI may consider how to customize quality report cards and target specific groups of consumers in dissemination. [ABSTRACT FROM AUTHOR]

We report a dynamic self-assembly system of ‘living’ polymeric chains sustained by chemistry using reactive molecular dynamics simulations. The linear polymeric chains consist of self-assembled nanoparticles connected by metastable linker molecules. As such, the polymeric chains, once assembled, undergo spontaneous dissociation driven by thermodynamics. However, with a continuous supply of linker molecules and the stored chemical energy therein, the polymeric chains can survive and maintain a steady state averaged chain length. These dynamically self-assembled polymeric chains are analogous to biological systems that both are thermodynamically metastable, yet dynamically stable upon continuous influx of matter and energy. [ABSTRACT FROM AUTHOR]

Atomic level computer simulation has become indispensable in understanding the mechanical properties of glasses, among other properties. However, the majority of model glasses are more ductile than their intended experimental counterparts, partially reflected by the overestimation of the Poisson's ratio. We have previously introduced an effective force field tuning method of imposing an additional energy penalty term to embrittle a binary Lennard-Jones glass. Here, we improved this method by varying the applied range of the energy penalty. The new method stabilizes the model glass even for high energy penalty values. Furthermore, unlike the old method, there is no unintended reduction in density for brittle glasses. Uniaxial tension tests were conducted to show the ductile-to-brittle transition as the energy penalty increases in strength. Crack propagation simulation was also conducted to demonstrate the efficacy of studying brittle fracture using the model glass. [ABSTRACT FROM AUTHOR]

The diamond cutting of transition metal alloys, particularly steel, is severely hindered by accelerated chemical wear of the tool. Recent experimental findings show that the presence of graphene platelets mitigates this problem. However, the specific mechanisms responsible for this wear mitigation are currently unknown. In this paper, molecular dynamics techniques are successfully used to identify these diamond tool wear mitigation mechanisms. A modified embedded atom method force field is first evaluated for its ability to accurately simulate the catalyzed graphitization of diamond in the presence of steel. This force field is then used to simulate nanometric diamond cutting of steel in the presence of a 1 or 3 layered graphene platelet. Coordination analysis of these simulations shows that the presence of the graphene platelet results in 34%–96% reduction in tool wear, when compared to the graphene-free cutting condition. This is attributed to the graphene platelet serving as a physical barrier protecting the tool cutting edge, and also as a sacrificial source for carbon transfer into the workpiece. Other mechanisms, such as platelet cleaving and interlayer sliding, are also observed. The reduction in tool wear reported by the simulations is comparable to the trends observed in prior experiments. [ABSTRACT FROM AUTHOR]

Most existing particle-based polymeric models are non-reactive, and usually constructed to be monodisperse. This deficiency limits the utilization of these models to understand the dependency of polymer properties on polydispersity. Here we report a coarse-grained model with pairwise interactions, yet is reactive and capable of in silico synthesis of polydisperse polymers in a step-wise manner. The polymerization of linear, branched, cross-linked and network polymers can be described by this reactive model. The chain length distribution of the resulting linear polymer agrees well with the Flory-Schulz distribution. The importance of polydispersity in polymer behaviors is highlighted in terms of kinetic (self-diffusivities of linear polymer melts) and mechanical properties (stress-strain responses of linear polymer glasses under uniaxial tension). [ABSTRACT FROM AUTHOR]

A new strategy for the preparation of Fe3O4 nanocrystals (NCs) and FePt bimetal NCs with amphiphilic hyperbranched polymers as unimolecular nanoreactors has been described. The amphiphilic hyperbranched polymers were synthesized by grafting methyl acrylate to hyperbranched poly(ethylenimine)s (HPEI) with the help of Michael addition reaction. The hydrophilic HPEI core was used to stabilize the magnetic NCs, whereas the hydrophobic methyl ester terminals can prevent the aggregation of polymers and NCs, thus magnetic NCs with a narrow size distribution were prepared. The resulting Fe3O4 NC/amphiphilic hyperbranched polymer nanocomposites also showed slightly better magnetofection property than HPEI transfection and their luciferase expression level in maximum was 1.3-fold greater than that for HPEI transfection. POLYM. COMPOS., 37:429-434, 2016. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

• Physics- and chemistry-informed machine learning models were developed for predicting glass properties. • Young's modulus, shear modulus and electrical resistivity were predicted by artificial neural network (ANN), support vector machine (SVM), and random forest (RF) models. • Relationships between glass properties and their first and second important features were revealed. Physics- and chemistry-informed machine learning (ML) models were trained by using descriptors in the element physical and chemical properties domain, which include stoichiometric, elemental-property-based, valance orbital occupation, and ionicity features. Young's modulus, shear modulus and electrical resistivity (ρ) data for a group of oxide glasses were used to train artificial neural network (ANN), support vector machine (SVM), and random forest (RF) models. In comparison with experimental values, the ANN performs the best in predicting elastic moduli, whereas the RF is the best in predicting the temperature dependence of ρ in terms of the coefficient of determination (R2) value. The benefits of the ML models using descriptors in the element physical and chemical properties domain were demonstrated by revealing the relationships between the predicted glass properties and their first and second important features through a grid search. [ABSTRACT FROM AUTHOR]

In order to investigate the relationships between the stability of Cu complexes and the nitrification inhibition effects of corresponding ligands, the effects of 22 kinds of Cu (II) ligands and eight kinds of Cu (I) ligands were evaluated in three types of soil on nitrification potentials (NPs) under short-term incubation (5 h) and nitrification inhibitory rates (NIRs) under long-term incubation (14 d). The results showed that the inhibitory effect of Cu (II) or Cu (I) ligands on nitrification exhibited significant linear relationships (P< 0.01) with the logarithms of the first stability constants (lgK1) and the total stability constants (lgKf) of corresponding complexes. Furthermore, lgKfof Cu (II) complexes exhibited a greater linear correlation than the corresponding lgK1with the nitrification inhibition effects of the corresponding ligands; lgKfof Cu (I) complexes exhibited a steeper linear relationship than that of Cu (II) complexes with NPs or NIRs, and hence, nitrification inhibition effects of Cu (I) ligands almost doubled that of Cu (II) ligands when the lgKfvalues of Cu (I) and Cu (II) complexes have the same changes. [ABSTRACT FROM PUBLISHER]

We review a minimalist's reactive force field, reactive state summation (RSS) potential. The essence of RSS potential scheme is to model each reactive state by individual non-reactive force fields, then modulate each term by a reaction-coordinate-dependent weight function, finally sum together to obtain the reactive potential. Compared with existing reactive potentials, RSS potential is easier to formulate and parameterise and is computationally efficient, at the expense of lesser accuracy. Thus, RSS potential can be regarded as a ‘reactive Lennard-Jones’ potential. Three exemplary RSS potentials are described in the context of their respective chemical systems: RSS-nitrogen for modelling detonation, RSS-carbon for modelling pyrolysis of activated carbon and RSS-fuel-catalyst for modelling catalytic chemical reaction. [ABSTRACT FROM AUTHOR]

Tensile fracture of metallic glasses due to shear-band-to-crack transition was studied by molecular dynamics. Such transition is difficult to characterize experimentally as it occurs within nanoseconds in the buried nanometer-thin shear band. We show that the sample fractures via shear band cavitation under high initial tensile stress, or with long sample length. The critical thermomechanical conditions for shear band cavitation, strongly influenced by shear, were identified. An analytical model was developed, leading to a length scale and a time scale for shear-band-to-crack transition. [ABSTRACT FROM AUTHOR]

This paper deals with the anti-triangular operator matrix M=(ABC0 with A2=A and CAπB=0). Using the resolvent expansion technique, we obtain the explicit representation of the Drazin inverse of M, in terms of its entries and the Drazin inverses of the entries and their compositions. The result extends the main results in Bu et al. (2011) [2] and Castro-González and Dopazo (2005) [6] and the results on group inverses in Bu et al. (2008) [3] and Liu and Yang (2012) [14]. As an application, a new additive result is given of the Drazin inverse for two matrices P, Q∈ Cn×n with P2=P and PQ2=0. [ABSTRACT FROM AUTHOR]

In medical image analysis, collecting multiple annotations from different clinical raters is a typical practice to mitigate possible diagnostic errors. For such multirater labels' learning problems, in addition to majority voting, it is a common practice to use soft labels in the form of full-probability distributions obtained by averaging raters as ground truth to train the model, which benefits from uncertainty contained in soft labels. However, the potential information contained in soft labels is rarely studied, which may be the key to improving the performance of medical image segmentation with multirater annotations. In this work, we aim to improve soft label methods by leveraging interpretable information from multiraters. Considering that mis-segmentation occurs in areas with weak supervision of annotations and high difficulty of images, we propose to reduce the reliance on local uncertain soft labels and increase the focus on image features. Therefore, we introduce local self-ensembling learning with consistency regularization, forcing the model to concentrate more on features rather than annotations, especially in regions with high uncertainty measured by the pixelwise interclass variance. Furthermore, we utilize a label smoothing technique to flatten each rater's annotation, alleviating overconfidence of structural edges in annotations. Without introducing additional parameters, our method improves the accuracy of the soft label baseline by 4.2% and 2.7% on a synthetic dataset and a fundus dataset, respectively. In addition, quantitative comparisons show that our method consistently outperforms existing multirater strategies as well as state-of-the-art methods. This work provides a simple yet effective solution for the widespread multirater label segmentation problems in clinical diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: A novel poly(methacrylic acid) (PMAA) microcarriers coated with nanolayered chitosan(Cs) and carboxyl modified multi-walled carbon nanotubes (MWCNTs-COOH) via self-assembly method, has been successfully prepared for better loading and sustained release of gatifloxacin (GFLX). Due to the multi-loading and gradient release properties, PMAA/Cs/CNTs could adsorb a great amount of drug (84.89±9.63μgmg−1), and 64.74±2.78% of its loading could slowly release in 24h, which is important to delivery GFLX effectively and to reduce the risk of side effects. [Copyright &y& Elsevier]

Abstract: Let be a complex Banach algebra with unit and let be two idempotents in . For , the authors obtain an explicit representation formula for the Drazin inverse of and give the upper bound of the corresponding Drazin index by using the presented method. As a consequence, the main previously published results on Drazin inverse of are corollaries of our theorem. Finally, the authors apply the theorem to an example which cannot be solved by previously known results. [Copyright &y& Elsevier]

Abstract: Nanoporous carbon (NPC) is structurally complex yet poorly understood, particularly the topological defects such as pentagon rings. Here we propose a computational approach that links the topological defects to structure factor S(q) measured from X-ray experiments. The essence of this method is to generate a large dataset of realistic NPC models by virtual synthesis procedures, from which both the population of topological defects and the S(q) can be calculated, and subsequently correlated. Three virtual synthesis procedures are utilized here to mimic high-energy electron irradiation, pyrolysis with rigid pentagon-rich precursors and pyrolysis with C60 molecules. The resulting population of topological defects is estimated based on an ensemble of NPC models, partially addressing the common non-uniqueness problem. As an example, we found that, in a low-density saccharose-based activated carbon sample, there should be fewer than one pentagon per 20 carbon atoms. Further analysis of this dataset of NPC model shows that the pore size distributions are insensitive to pentagon defects. Thus, adsorption experiments may not help directly characterize topological defects in NPC. On the other hand, as local curvature is sensitive to the ring defects, 3D tomography is likely to be capable of directly characterizing the population of topological defects. [Copyright &y& Elsevier]

Precise prediction of phase diagrams in molecular dynamics simulations is challenging due to the simultaneous need for long time and large length scales and accurate interatomic potentials. We show that thermodynamic integration from low-cost force fields to neural network potentials trained using density-functional theory (DFT) enables rapid first-principles prediction of the solid–liquid phase boundary in the model salt NaCl. We use this technique to compare the accuracy of several DFT exchange–correlation functionals for predicting the NaCl phase boundary and find that the inclusion of dispersion interactions is critical to obtain good agreement with experiment. Importantly, our approach introduces a method to predict solid–liquid phase boundaries for any material at an ab initio level of accuracy, with the majority of the computational cost at the level of classical potentials. [ABSTRACT FROM AUTHOR]