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Accurate dose delivery is crucial for cervical cancer volumetric modulated arc therapy (VMAT). We aimed to develop a robust deep-learning (DL) algorithm for fast and accurate dose prediction of cervical cancer VMAT in multicenter datasets and then explore the feasibility of the DL algorithm to endometrial cancer VMAT with different prescriptions. We proposed the AtTranNet algorithm for three-dimensional dose prediction. A total of 367 cervical patients were enrolled in this study. Three hundred twenty-two cervical patients from 3 centers were randomly divided into 70%, 10%, and 20% as training, validation, and testing sets, respectively. Forty-five cervical patients from another center were selected for external testing. Moreover, 70 patients of endometrial cancer with different prescriptions were further selected to test the model. Prediction precision was evaluated by dosimetric difference, dose map, and dose-volume histogram metrics. The prediction results were all clinically acceptable. The mean absolute error within the body in internal testing was 0.66 ± 0.63%. The maximum |δD| for planning target volume was observed in D98, which is 1.24 ± 2.73 Gy. The maximum |δD| for organs at risk was observed in Dmean of bladder, which is 4.79 ± 3.14 Gy. The maximum |δV| were observed in V40 of pelvic bones, which is 4.77 ± 4.48%. AtTranNet showed the feasibility and reasonable accuracy in the dose prediction for cervical cancer in multiple centers. The model can also be generalized for endometrial cancer with different prescriptions without any transfer learning. • Proposed state-of-the-art model to predict the radiotherapy dose intelligently. • Automatic prediction results were stable across medical centers. • Computer-aided dose prediction can accelerate treatment planning. • The model also showed good generalizability for endometrial cancer. [ABSTRACT FROM AUTHOR]

Direct and resonant photoionization of Al-like W61+ ions from their ground state 1 s 2 2 s 2 2 p 6 3 s 2 3 p 2 P 1 / 2 and four lowly excited states 1 s 2 2 s 2 2 p 6 3 s 2 3 p 2 P 3 / 2 , 1 s 2 2 s 2 2 p 6 3 s 3 p 2 4 P 1 / 2 , 3 / 2 , and 1 s 2 2 s 2 2 p 6 3 s 3 p 2 2 D 5 / 2 is studied by using the multiconfigurational Dirac–Fock method and the relativistic R-matrix method. Emphasis is placed upon exploring direct and resonant ionization limits and also upon identifying possible resonance channels of W61+ ions. To do so, the photoionization cross sections are calculated with the use of the Dirac Atomic R-matrix Code. For the ground-state photoionization, the direct and resonant ionization limits are obtained, and the identified resonance peaks are found to be associated with the resonances 1 s 2 2 s 2 2 p 6 3 s 3 l n l ′ and 1 s 2 2 s 2 2 p 6 3 p 3 l n l ′ (l , l ′ = p , d) at a level of fine-structure energy level or configuration. For the excited-state photoionization, however, although the respective direct ionization limits are obtained, the resonant ionization limits and resonance peaks are hardly distinguishable due to much more densely spaced resonance peaks and complex resonance structure. It is expected that the present work could fill the vacancy of studies on the photoionization of W61+ ions and be helpful to the diagnosis and simulation of the thermonuclear fusion plasmas together with other available photoionization data of tungsten ions with other charge states. [ABSTRACT FROM AUTHOR]

Using historical traffic flow information to accurately and real-time predict future traffic flow information is particularly important for the management and control of traffic scenarios, and the guidance and planning of traffic travel. Short-term traffic flow prediction requires a large amount of forecast data and complex changes in traffic flow in space and time. However, the current prediction model cannot meet the requirements of real-time and accuracy of short-term traffic flow prediction. This paper proposes two traffic flow prediction models based on the changing trend and correlation of short-term traffic flow in time and space, combined with deep learning related theories. Firstly, this paper takes the traffic flow of the expressway as the research object, explores the basic parameters of traffic flow-flow, speed occupancy rate in time and space distribution law and change trend, and selects the speed as the research object, analyzes its temporal and spatial characteristics and correlation to provide data support for this study. Then, this paper introduces the related theories and frameworks of deep learning, mainly including neural network theory and hyperparameter optimization theory, as well as the deep learning model design framework. Pytorch and hyperparameter optimization framework Optuna, so as to provide theoretical foundation and technical support for this research. Finally, experiments of short-term traffic prediction based on single detection point and short-term traffic prediction based on multiple detection points are carried out on the PeMS dataset. Firstly, a multi-lane spatiotemporal convolutional network model (MSCTAN) based on traffic flow prediction at a single detection point is proposed to capture the spatiotemporal correlation of multi-lane traffic at a single detection point. Spatiotemporal Convolution and Spatiotemporal Attention Network Model (MSCSAN). For the two models proposed in this paper, comparative experiments were designed, and the mean absolute error (MAE), the root mean square error (RMSE) and the mean absolute percentage error (MAPE) were used as evaluation indicators to verify their performance at a single detection point and multiple detection points. The results show that, whether it is a single detection point experiment or a multi-detection point experiment, the two models achieve the best performance compared with the comparison model. [ABSTRACT FROM AUTHOR]

A dynamic constitutive model of fiber-reinforced resin matrix composites considering temperature effect was proposed. It was used to predict the impact limit speed of composite laminates. High-speed bullet impact tests of fiber-reinforced resin matrix composite laminates were carried out at 25, 160, and 200°C, and the impact limit speed Vc was calculated using the test results. The test results showed that Vc of carbon-fiber-reinforced resin matrix composite laminates decreased with increasing ambient temperature. On this basis, a dynamic failure model of fiber-reinforced resin matrix composites was established considering the influence of ambient temperature. A VUMAT user subroutine was also developed to embed the failure model into the finite-element analysis software package. Then, the high-speed impacts of composite laminates at different temperatures were simulated numerically. The magnitude of Vc was predicted by the bisection method. A comparison of simulation results with test data showed that the error was smaller than 5%. [ABSTRACT FROM AUTHOR]

Improved physical fitness is important for preventing COVID-19-related mortality. So, combined training can effectively increase peak oxygen consumption, physical fitness, body composition, blood pressure, and the healthrelated characteristics of adults; however, its impact in the elderly remains unclear. This systematic review and meta-analysis aimed to evaluate the effects of combined training on older adults. Four electronic databases (PubMed, Scopus, Medline, and Web of Science) were searched (until April 2021) for randomized trials comparing the effect of combined training on cardiorespiratory fitness, physical fitness, body composition, blood pressure, and cardiometabolic risk factors in older adults. Combined training significantly improved peak oxygen consumption compared to no exercise (WMD = 3.10, 95% CI: 2.83 to 3.37). Combined resistance and aerobic training induced favorable changes in physical fitness (timed up-and-go = −1.06, 30-s chair stand = 3.85, sit and reach = 4.43, 6-minute walking test = 39.22, arm curl = 4.60, grip strength = 3.65, 10-m walk = −0.47, maximum walking speed = 0.15, one-leg balance = 2.71), body composition (fat mass = −2.91, body fat% = −2.31, body mass index = −0.87, waist circumference = −2.91), blood pressure (systolic blood pressure = −8.11, diastolic blood pressure = −4.55), and cardiometabolic risk factors (glucose = −0.53, HOMA-IR = −0.14, high-density lipoprotein = 2.32, total cholesterol = −5.32) in older individuals. Finally, the optimal exercise prescription was ≥ 30 min/session × 50–80% VO2peak, ≥ 3 times/week for ≥ 12 weeks and resistance intensity 70–75% one-repetition maximum, 8–12 repetitions × 3 sets. Combined training improved VO2peak and some cardiometabolic risk factors in older populations. The dose–effect relationship varied between different parameters. Exercise prescriptions must be formulated considering individual needs during exercise. [ABSTRACT FROM AUTHOR]

Composites are widely used in high performance structures such as aerospace structures due to their excellent properties. The analysis of failure evolution of composite perforated structures by finite element simulation is of great significance for practical work as engineering composite structures often contain notches and voids. In this paper, the numerical simulation of failure evolution and failure modes of carbon fiber reinforced resin composite laminates with large openings was carried out. A UMAT subroutine was written based on the 3D Hashin-Ye failure criterion and progressive damage model theory. The characteristic length and viscosity coefficient were introduced into the model to reduce mesh dependency and improve computational convergence. The nonlinear shear constitutive relationship defined by the Ramberg–Osgood equation was introduced into the continuous damage degradation model. The effect of nonlinear shear on the failure evolution of laminates with different stacking sequence was studied. [ABSTRACT FROM AUTHOR]

Nitrate has become the primary inorganic compound in urban aerosol particles, but its effects on particle phase state, which is crucial in multiphase chemistry, remains largely unknown. Herein, particle rebound measurements were conducted to explore the relationship between the liquid–phase–transition threshold relative humidity (RHthreshold) and the inorganic compounds mass fraction in dry particles (Finorg). Results revealed negative correlations between RHthreshold and Finorg, with more nitrate leading to lower RHthreshold. Even with RH < 20%, particles with ∼50% nitrate mass fraction remained in non‐solid state. Taking Beijing as an example, decreases were observed in RHthreshold from 64% in 2015 to below 53% nowadays during the moderate‐pollution periods (PM2.5 = 35–75 μg/m3) due to an enhanced nitrate fraction. This allowed urban aerosol particles to exist in liquid state at lower RH, and consequently, kinetic limitation by bulk diffusion in nitrate‐dominated particles might be negligible, making them key seeds for secondary aerosol formation through multiphase reactions. Plain Language Summary: The phase state of aerosol particles plays a crucial role in the mass‐transfer processes between gas and particles, which is essential for determining particle mass concentration. Investigating the characteristics of the aerosol phase state is crucial for comprehending the mechanisms behind secondary particle formation and improving air quality. Currently, the chemical composition of urban aerosol particles has shown notable changes. The mass fraction of inorganic components has increased, with nitrate emerging as the dominant inorganic component. However, the impacts of these changes on the phase state of urban aerosol particles remain largely unknown. This study demonstrates that particles with a higher mass fraction of inorganic compounds, particularly nitrate, tend to exist in a liquid state. Consequently, an increased nitrate fraction allows urban aerosol particles to exist in a liquid state at lower relative humidity levels. These findings suggest that changes in the phase state of particles due to changes in chemical properties in urban aerosol particles should be considered to accurately gauge the mass‐transfer processes and promote the air quality improvements in urban cities. Key Points: Particles with more inorganic compounds, particularly nitrate, can exist in a liquid state at lower relative humidity levelsParticles with normalized aerosol liquid water content larger than 0.3 exist in a liquid stateNitrate‐dominated particles can serve as key seeds where secondary aerosol formation can occur via multiphase reactions [ABSTRACT FROM AUTHOR]

The micro-randomized trial is a sequential randomized experimental design to empirically evaluate the effectiveness of mobile health intervention components that may be delivered at hundreds or thousands of decision points. Micro-randomized trials have motivated a new class of causal estimands, termed causal excursion effects , for which semiparametric inference can be conducted via a weighted, centred least-squares criterion (Boruvka et al. 2018). Causal excursion effects allow health scientists to answer important scientific questions about how intervention effectiveness may change over time or may be moderated by individual characteristics, time-varying context or past responses. Existing definitions and associated methods assume between-subject independence and noninterference. Deviations from these assumptions often occur. In this paper, causal excursion effects are revisited under potential cluster-level treatment effect heterogeneity and interference, where the treatment effect of interest may depend on cluster-level moderators. Utility of the proposed methods is shown by analysing data from a multi-institution cohort of first-year medical residents in the United States. [ABSTRACT FROM AUTHOR]

Grating-based x-ray phase-contrast imaging has been demonstrated to provide more information and higher-contrast images for low-Z soft tissues, compared with conventional absorption-based imaging. However, the existing Talbot–Lau phase-contrast devices are operated in either a two- or three-dimensional mode at low energy with a small field of view and long exposure time. This is because of coherence limitations, difficulties in fabricating high aspect ratio gratings, and the slow readout speed of the detector. For preclinical or even clinical applications, a variable x-ray energy, a large field of view, and fast phase-contrast computed tomography (CT) devices are desirable. The noninterferometric grating-based phase-contrast imaging method is a good candidate, as it relaxes requirements on gratings, including grating period and aspect ratio. Based on the noninterferometric imaging principle, we constructed a prototype phase-contrast CT system, at the National Synchrotron Radiation Laboratory of the University of Science and Technology of China, with medical imaging components. This prototype system enables a large field of view and fast phase-contrast CT imaging under medical imaging energies. In this paper, the prototype system and preliminary experimental results are reported, and possible optimization for forthcoming work is also discussed. [ABSTRACT FROM AUTHOR]

Within the framework of the density matrix theory, the angular distribution of the characteristic magnetic-quadrupole line 1 s 2 p 3 P 2 → 1 s 2 1 S 0 following electron-impact excitation of heliumlike thallium ions with nuclear spin I = 1 / 2 has been investigated by using the multiconfigurational Dirac–Hartree–Fock method and the relativistic distorted-wave theory. Special attention has been paid to exploring the question of how the angular distribution of the characteristic line is affected by the multipole interference between the dominant magnetic-quadrupole and hyperfine-induced electric-dipole decay channels of its hyperfine-structure-resolved component 1 s 2 p 3 P 2 , F = 3 / 2 → 1 s 2 1 S 0 , F 0 = 1 / 2 . To this aim, detailed calculations are performed for spin-1/2 81 187 Tl 79 + and 81 207 Tl 79 + ions with (relatively) large nuclear magnetic dipole moment. It is found that the hyperfine-induced multipole interference contributes to making the angular distribution of the magnetic-quadrupole line 1 s 2 p 3 P 2 → 1 s 2 1 S 0 less anisotropic for all the impact electron energies considered, although at any given impact energy its angular emission pattern remains always qualitatively consistent with each other for both the two cases without and with the interference contribution included. Moreover, for the case with the interference considered the angular distribution of the magnetic-quadrupole line is found to be sensitive to the nuclear magnetic dipole moment of the spin-1/2 ions, especially at low impact electron energies. [ABSTRACT FROM AUTHOR]

Fastener technology is a key technology of Ballastless track structure in high-speed railway, and the elastic strip is the key component to realize fastener function. To this end, a special loading fixture is fabricated to explore the performance of the elastic strip under fatigue load. The working state of the elastic strip was simulated through the fatigue testing machine, and the stress-controlled loading modes and four loading amplitudes (25±5kN, 25±7.5kN, 25±10kN, 25±12.5kN) are investigated. The pressure control method is used for fatigue tests, and the results show that: (1) As the load amplitude increases, the fatigue life decreases sharply and its decreasing speed is greater than the increasing speed of load amplitude; (2) The buckling pressure and displacement curves of the elastic strip have the characteristics of "increasing step-by-step" and "decreasing step-bystep"; (3) In the fatigue test, the attenuation of buckling pressure is 22% - 33% and the displacement at the front end of the ring is 18% - 25%; (4) According to the results, the buckling pressure curve and the displacement curve of the ring in the elastic strip are drawn, and the equations of them are fitted to estimate the service performance of the elastic strip. [ABSTRACT FROM AUTHOR]

In this paper, the epoxy resin composite filled with wood fiber and fly ash cenosphere was prepared. In order to improve the bonding properties between wooden fiber/fly ash cenosphere and epoxy resin, the grafting treatment of wooden fiber and fly ash cenosphere surfaces was carried out here using KH550 type silane coupling agent. The effects of different process parameters on the surface modification effect of wooden fiber and fly ash cenosphere were investigated, the mechanical properties and energy absorption characteristics of the materials before and after the filler modification were tested, and the microscopic interfacial structures of the matrix with wooden fiber and fly ash cenosphere were investigated by scanning electron microscopy. Meanwhile, based on LS‐DYNA simulation software, the energy‐absorbing performance of energy‐absorbing boxes prepared from AA6061 aluminum alloy and modified wooden fiber‐fly ash cenosphere/epoxy resin composites were compared in low‐velocity collisions. [ABSTRACT FROM AUTHOR]

Thermodynamic behavior has been extensively used to evaluate the stability of materials and predict the direction of the chemical reaction at different pH values, temperatures, potentials, and ion concentrations. Although researching efforts on Sn species in an aqueous solution system (Sn/H2O) of acid, alkali, and salt have been reported, scattered data leads to the inefficiency of a thermodynamic method in the practical application. This article provides a brief review on the potentialpH diagram for Sn/H2O system, which reflects the thermodynamic behavior of Sn species in an aqueous solution and extracts thermodynamic data for the practical application of Sn species. Firstly, the relationship of the thermodynamic behavior, potential-pH diagram, and equilibrium relations of Sn species for Sn/H2O system was overviewed. Additionally, the potential-pH diagram of Sn/H2O system at different temperatures (298 K, 373 K, and 550 K), dissolved Sn activities (1, 10-1, 10-3, and 10-6), and the potential-pH diagram of the Sn species in a chloridion aqueous solution (Sn/H2O-Cl) was summarized. Finally, the application prospect of the potential-pH diagram for Sn/H2O system was investigated in the intelligent simulation of Sn metallurgy and the practical application of Sn materials. [ABSTRACT FROM AUTHOR]

In this paper, the double‐element composites were developed, which contained the epoxy resin as matrix phase and carbon black rubber powder as toughening materials. Quasi‐static compression tests on epoxy resin and different mass fractions carbon black rubber powder‐epoxy resin composites were performed in room temperature to test their compression properties. The energy absorption performance and the energy absorption efficiency of the composites were calculated according to the compression curve. The fracture characteristics of the micro appearance of the compressed material specimen were observed by scanning electron microscope. The deformation mode of the composite was analyzed. By systematically analyzing the effects of carbon black rubber powder content on the mechanical properties of carbon black rubber powder‐epoxy resin, it was found that carbon black rubber powder as a reinforced material could effectively improve the brittleness of epoxy resin, the yield strength and the adsorption properties and efficiency of composites. With the mass fraction of carbon black rubber powder increasing, the energy absorption performance of carbon black rubber powder‐epoxy resin first increases and then decreases. The most significant performance observed was at a mass fraction of 5 % in carbon black rubber powder‐epoxy resin composites. [ABSTRACT FROM AUTHOR]

Resonance frequency drift caused by a change in temperature greatly limits the application of high-Q resonators with high temperature sensitivity in photoacoustic (PA) gas detection systems. In this work, a chirp-wavelength combined modulation method was designed by incorporating a real-time frequency scanning in wavelength-modulated PA spectroscopy to reduce the influence of temperature changes on measurement. Theoretical analysis shows that the chirp rate depends on the precision requirements and the cutoff frequency of the cascaded low-pass filter. Trace acetylene measurement experiment at varying temperature verified that the proposed method can significantly reduce the temperature sensitivity within a preset temperature range. Thus, this method can effectively reduce the temperature sensitivity of a high-Q resonator for improving the measurement accuracy and detection limit in trace gas detection. [ABSTRACT FROM AUTHOR]

The effects of antimony on eutectic silicon and fracture mode of A357 alloy were investigated at slow and fast cooling rates by scanning electron microscopy, transmission electron microscopy, polarizing microscope, differential scanning calorimetry, optical microscope and tensile testing. The slow cooling rate is 0.16 °C/s, and the fast cooling rate is 3.20 °C/s. The results show that with antimony addition, the eutectic silicon of A357 alloy is modified. Antimony does not modify eutectic silicon of A357 alloy by increasing the number of twins. Under the same cooling rate condition, with antimony addition, the volume fraction of eutectic phases increases, and when studying the modification of eutectic silicon of some modifiers, we also need to study the eutectic phases including eutectic silicon and eutectic α‐aluminum. With antimony addition, tensile strength and elongation of A357 alloy increase, especially under fast cooling rate conditions. With the increase of elongation, the fracture mode of A357 alloy changes from I to I+II to I+II+III. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) ceramics with aluminum oxide (Al2O3)/aluminum nitride (AlN) and yttrium(III) oxide (Y2O3) as sintering aids are hot-pressed. The microstructure and tribological behavior of the as-prepared SiC ceramics slide against tungsten carbide (WC, Co bonded) and Al2O3 under variable velocities, loads, and temperatures are studied. The results showed that by using Al2O3–Y2O3 as a sintering aid, a fully dense (98%) SiC ceramic is obtained at 1950°C and 13 MPa. In the sample coupled with WC, the friction coefficient (CoF) of the SiC ceramic is observed low at the applied high load, velocity, and temperature. On the other hand, in the sample coupled with Al2O3, the CoFs of the SiC ceramics are found low at the applied high load, moderate velocity, and low temperature. Coupled with the two tribo-pairs, the wear rates (WRs) of the SiC ceramics are not sensitive to the change in load, while CoF and WR of SiC ceramic increase with velocity initially, and then decrease. At 0.05 m/sec and 1.0 m/sec, the WRs of both tribo-pairs are as low as 10 – 5 mm3 · N – 1 · m – 1. The reduction in CoFs and WRs is strongly related to the formation of tribo-layers. [ABSTRACT FROM AUTHOR]

In X-ray grating-based phase contrast imaging, information retrieval is necessary for quantitative research, especially for phase tomography. However, numerous and repetitive processes have to be performed for tomographic reconstruction. In this paper, we report a novel information retrieval method, which enables retrieving phase and absorption information by means of a linear combination of two mutually conjugate images. Thanks to the distributive law of the multiplication as well as the commutative law and associative law of the addition, the information retrieval can be performed after tomographic reconstruction, thus simplifying the information retrieval procedure dramatically. The theoretical model of this method is established in both parallel beam geometry for Talbot interferometer and fan beam geometry for Talbot-Lau interferometer. Numerical experiments are also performed to confirm the feasibility and validity of the proposed method. In addition, we discuss its possibility in cone beam geometry and its advantages compared with other methods. Moreover, this method can also be employed in other differential phase contrast imaging methods, such as diffraction enhanced imaging, non-interferometric imaging, and edge illumination. [ABSTRACT FROM AUTHOR]

A spatially averaged, time-dependent global plasma model has been developed to describe the reactive deposition of a TiAlSiN thin film by modulated pulsed power magnetron sputtering (MPPMS) discharges in Ar/N2 mixture gas, based on the particle balance and the energy balance in the ionization region, and considering the formation and erosion of the compound at the target surface. The modeling results show that, with increasing the N2 partial pressure from 0% to 40% at a constant working pressure of 0.3 Pa, the electron temperature during the strongly ionized period increases from 4 to 7 eV and the effective power transfer coefficient, which represents the power fraction that effectively heats the electrons and maintains the discharge, increases from about 4% to 7%; with increasing the working pressure from 0.1 to 0.7 Pa at a constant N2 partial pressure of 25%, the electron temperature decreases from 10 to 4 eV and the effective power transfer coefficient decreases from 8% to 5%. Using the modeled plasma parameters to evaluate the kinetic energy of arriving ions, the ion-to-neutral flux ratio of deposited species, and the substrate heating, the variations of process parameters that increase these values lead to an enhanced adatom mobility at the target surface and an increased input energy to the substrate, corresponding to the experimental observation of surface roughness reduction, the microstructure transition from the columnar structure to the dense featureless structure, and the enhancement of phase separation. At higher N2 partial pressure or lower working pressure, the modeling results demonstrate an increase in electron temperature, which shifts the discharge balance of Ti species from Ti+ to Ti2+ and results in a higher return fraction of Ti species, corresponding to the higher Al/Ti ratio of deposited films at these conditions. The modeling results are well correlated with the experimental observation of the composition variation and the microstructure transition of deposited TiAlSiN compound films, demonstrating the applicability of this approach in understanding the characteristics of reactive MPPMS discharges as well as the composition and microstructure of deposited compound films. The model for reactive MPPMS discharges has no special limitations and is applicable to high power impulse magnetron sputtering discharges as well. [ABSTRACT FROM AUTHOR]

In order to meet the requirements of cutting efficiency and economy in the processing of stone plastic composite, milling tests of the stone plastic composite were conducted using straight tooth diamond tools. Cutting forces and temperature were measured under different cutting parameters. Response surface methodology was used to analyze the variation of cutting forces and temperature and to determine the significant contribution of each variable and its two‐level interaction. The correlation between actual and predicted results was found by building mathematical models of cutting forces and temperatures, which can be used to make accurate predictions. At last, the optimal cutting parameters for stone plastic composite straight‐tooth milling with low cutting forces and cutting temperatures were found to be 10° front angle, 37.9 m/s cutting speed, 0.32 mm feed per tooth, and 0.5 mm milling depth. It is possible to improve processing efficiency and reduce production costs by using these parameters in industrial processing. [ABSTRACT FROM AUTHOR]

Abrupt cooling is observed at the end of interglacials in many paleoclimate records, but the mechanism responsible remains unclear. Using model simulations, we demonstrate that there exists a threshold in the level of astronomically induced insolation below which abrupt changes at the end of interglacials of the past 800,000 years occur. When decreasing insolation reaches the critical value, it triggers a strong, abrupt weakening of the Atlantic meridional overturning circulation and a cooler mean climate state accompanied by high-amplitude variations lasting for several thousand years. The mechanism involves sea ice feedbacks in the Nordic and Labrador Seas. The ubiquity of this threshold suggests its fundamental role in terminating the warm climate conditions at the end of interglacials. [ABSTRACT FROM AUTHOR]

The crystallization mechanism in deeply undercooled ZrCu metallic glass-forming liquids was investigated via molecular dynamics simulations. It was found that the crystallization process is mainly controlled by the growth of crystal nuclei formed by the BCC-like atomic clusters, consistent with experimental speculations. The crystallization rate is found to relate to the number of growing crystal nuclei in the crystallization process. The crystallization rate in systems with more crystal nuclei is significantly hindered by the larger surface fractions of crystal nuclei and their different crystalline orientations. It is further revealed that in the crystallization in deeply undercooled regions, the BCC-like crystal nuclei are formed from the inside of the precursors formed by the FCC-like atomic clusters, and growing at the expense of the precursors. Meanwhile, the precursors are expanding at the expense of the outside atomic clusters. This process is consistent with the so-called Ostwald step rule. The atomic structures of metallic glasses are found to have significant impact on the subsequent crystallization process. In the Zr85Cu15 system, the stronger spatial correlation of Cu atoms could hinder the crystallization processes in deeply undercooled regions. [ABSTRACT FROM AUTHOR]

We investigated the ice nucleation activities of humic‐like substances (HULIS), an important component of organic aerosol (OA), derived from atmospheric and biomass burning aerosols, and produced from aqueous‐phase chemical reactions. Respective HULIS can effectively trigger heterogeneous IN under mixed‐phase cloud conditions. HULIS ice active entities (IAE) were aggregates in size between 0.02 and 0.10 μm. At −20°C, the IAE numbers per unit HULIS mass varied from 213 to 8.7 × 104 mg−1. Such results were different than those detected in aquatic humic substances (HS) from previous studies, implying using HS as surrogates may not robustly estimate the IAE concentrations in the real atmosphere. Combining the abundance of atmospheric HULIS with the present results suggests that HULIS could be an important IAE contributor in the atmosphere where other ice nucleating particle species, such as dust and biological particles, are either low in concentration or absent. Plain Language Summary: Humic‐like substances (HULIS), a ubiquitous component of atmospheric organic aerosol, were found to nucleate ice under mixed‐phase cloud conditions. HULIS ice active entities (IAE) were shown to be aggregates in size between 0.02 and 0.10 μm. The concentration of IAE per unit mass of HULIS varied from 213 to 8.7 × 104 mg−1 at −20°C. Such results were different than those detected in aquatic humic substances done by previous studies. Combining the reported concentrations of HULIS in the atmosphere with the present results suggests that HULIS could be important ice nucleating particle contributor in the atmosphere. Key Points: Humic‐like substances (HULIS) originating from atmospheric and biomass burning aerosols, and produced from aqueous‐phase reactions, can trigger immersion freezingThe abundance of ice active entities (IAE) per unit HULIS mass varied from 213 to 8.7 × 104 mg−1 at −20°CHULIS could be an important IAE contributor in the atmosphere where other ice nucleating particle species are either low in concentration or absent [ABSTRACT FROM AUTHOR]

A new vibrational spectroscopy method aimed at the investigation of solid surfaces in ultrahigh vacuum, called "Surface Action Spectroscopy (SAS)", is described and the first results are reviewed. This technique is based on ideas and experiments performed in the gas phase. A surface is exposed to a messenger species at low temperature. This messenger species is desorbed via absorption of tunable infrared light from a free‐electron laser and the desorption rate of the messenger species is recorded via mass spectrometry. It is shown that the technique is extremely surface sensitive and we discuss the basic mechanisms of the technique. We show a feasibility study on a V2O3(0001) surface, where we know the surface structure. We then proceed to the example of iron oxide films to study the surface structure in parallel with calculations of the surface phonons, which allow us to confirm the surface structure of Fe3O4(111) to be Fetet terminated. It also provides evidence for the so‐called biphase structure. To conclude, we discuss possibilities to apply the technique to interesting questions in model and real catalysis, since the technique may provide interesting information independent of long‐range order of the sample. [ABSTRACT FROM AUTHOR]

The electron-impact excitations from the ground state to the excited levels and as well as the subsequent radiative decays of neonlike Fe16+ ions have been investigated within the framework of the multiconfigurational Dirac–Fock method and the relativistic distorted-wave theory. Special attention has been paid to emission behaviors of the astrophysically relevant resonance 3C and intercombination 3D lines emitted in the radiative decays of Fe16+ ions. To this end, we calculate the angular distribution and linear polarization of both of the lines for a series of impact electron energies. It is found that the angular and polarization behaviors of the resonance 3C line are nearly the same as those of the intercombination 3D line. Nevertheless, the angular and polarization behaviors of both of the lines are found to be very sensitive to the impact electron energy, especially at low impact energies. Based on such a sensitivity, it is expected that high-precision angular and polarization measurements of the 3C and 3D lines could be served as a tool for revealing detailed information such as electron energy of relevant laboratory and astrophysical plasmas. [ABSTRACT FROM AUTHOR]

The direct and resonant single-photon photoionization of W63+ ions from their ground state 1s22s22p63s2S1/2 and four lowly-excited states 1s22s22p63p2P1/2,3/2 and 1s22s22p63d2D3/2,5/2 has been studied within the framework of the relativistic R-matrix method and the multiconfigurational Dirac–Fock method. Special attention has been paid to obtaining direct and resonant ionization limits and to identifying possible resonant symmetries of W63+ ions. To this end, the photoionization cross-sections have been calculated using the Dirac Atomic R-matrix Code package. Direct and resonant ionization limits were obtained for the ground-state photoionization of W63+ ions, and the resonant peaks identified were found to be associated with the resonances 1s22s22p53lnl′ and 1s22s2p63lnl′ (l, l′ = s, p, d) for the fine-structured energy level or configuration at the level of fine structure or configuration. For excited-state photoionization, however, the resonant ionization limits and resonant peaks were hardly distinguishable due to much more densely spaced resonant peaks and a complicated resonant structure, although the respective direct ionization limits are obtained. We expect that this work will remedy the current lack of fundamental studies of the photoionization of W63+ ions and be helpful in the diagnosis and simulation of fusion plasmas in conjunction with the available photoionization data for tungsten ions in other charge states. [ABSTRACT FROM AUTHOR]

Artificial muscles actuated by negative pressure offer significant benefits over those driven by positive pressure, such as high contraction ratios and improved safety, making them a promising option for various applications. This paper studies the contraction force characteristic of a bellows-like artificial muscle actuated by negative pressure. Initially, the structure, fabrication, and working principle of the artificial muscle were introduced. Subsequently, based on the force balance method, the contraction force was decomposed as the forces acted by the difference value of the inner and the outer pressures on the end plate, and the tension force derived from the adjacent contraction unit. To reduce complexity, the contraction process was divided into three phases according to the distinct contact conditions of the contraction units: uncontacted, locally contacted, and fully contacted with crests. The deformations of the contraction units in each phase were analyzed, and the corresponding contraction forces were derived. An experiment platform was constructed to test the force by changing the dimension parameters and pressure, obtaining the output force data during isobaric contraction. Finally, a comparison of the experimental and calculated results substantiated the aptness of the theorem model. [ABSTRACT FROM AUTHOR]

Ricinoleic acid is a kind of unsaturated fatty acids in oil of castor bean (Ricinus communis) seeds with wide application value. However, there is little transcriptomic information on genes related to ricinoleic acid biosynthesis in castor beans. To better understand the regulation mechanism of ricinoleic acid biosynthesis, immature seeds at three developmental stages (S1, S2, and S3 corresponding to 15, 30, and 45 d after pollination) were collected. The results indicated that the accumulation of castor bean oil and ricinoleic acid increased gradually during seed development, and reached the maximum value at the late stages of seed development (45 d after pollination). Furthermore, RNA sequencing was conducted to analyze the transcriptome of the developing seeds at three developmental stages. Totals of 9 875 differentially expressed genes (DEGs) were identified among the three time points. Based on the annotation information, 49 DEGs related to lipid biosynthesis were screened among all DEGs. Through cluster analysis of the 49 DEGs, ten genes with increasing FPKM values from seed development stages S1 to S3 were selected as candidate key enzymes, since they showed similar patterns of increase with castor bean oil accumulation and ricinoleic acid biosynthesis during seed development. The transcriptomic data of the 10 candidate key enzyme genes was further validated by RT-qPCR. Ultimately, a putative model of key genes correlated with ricinoleic acid accumulation was built. Our study identified a series of key genes and revealed the proposed molecular mechanism of ricinoleic acid accumulation in castor bean seeds through the transcriptional analysis. It broadens our knowledge of ricinoleic acid biosynthesis and castor bean oil accumulation and also provides a theoretical foundation for the genetic engineering key genes that can improve the ricinoleic acid production in castor beans as well as in other plants. [ABSTRACT FROM AUTHOR]

Aims: Relatively, few anti‐biofilm polysaccharides against Pseudomonas aeruginosa were done to investigate the underlying molecular mechanism. Exopolysaccharide EPS273 can clearly reduce biofilm formation and infection of P. aeruginosa. This study aims to investigate its anti‐biofilm and anti‐infection mechanism on transcriptional level. Methods and Results: Herein, we used an RNA‐Seq transcriptomic approach to investigate the underlying anti‐biofilm and anti‐infection mechanism of EPS273. The expression levels of a large number of genes were changed after P. aeruginosa PAO1 was treated with EPS273. Especially, the genes related to biofilm formation, such as gene involved in production of extracellular matrix and virulence factor, genes involved in flagella and cell motility and genes involved in iron acquisition. Notably, the expression levels of genes involved in regulatory and signal transduction were markedly downregulated, such as two‐component system PhoP‐PhoQ and quorum sensing (QS) system LasI/LasR and RhlI/RhlR. Furthermore, when genes phoP and phoQ were disrupted, respectively, the reduction of biofilm formation and cell motility in mutant △phoP or △phoQ was also detected. Conclusion: EPS273 may exert its anti‐biofilm and anti‐infection function by downregulating gene expression of two‐component system PhoP‐PhoQ and QS systems LasI/LasR and RhlI/RhlR of P. aeruginosa, which further regulated expression of genes involved in biofilm formation. Significance and Impact of the Study: Our data will expand understanding of anti‐biofilm mechanisms of polysaccharides on transcriptomic level. [ABSTRACT FROM AUTHOR]

A numerical simulation analysis of mechanical chip morphology and residual stress for Ti6Al4V alloy was conducted under different cutting speed and feed rate. Johnson-Cook constitutive model and shear failure model were selected in the simulation procedure. The correlations between the mechanical chip morphology and surface residual stress were detailed. The results show that the chip morphology characterized with the degree of serration Gs and the serrated frequency f has a direct impact on residual stress distribution. With the increase of the degree of serration Gs, the maximum residual tensile stress decreases, while with the increase of the serrated frequency f, the maximum residual compressive stress increases on the surface. The research of the present paper provides a new way to understand and evaluate residual stress distribution for titanium alloy mechanical process. [ABSTRACT FROM AUTHOR]

Water tanks have been built for decades and likely deteriorated over time. To ensure its integrity, Unmanned Aerial Vehicle (UAV) e.g. drones with cameras are used for inspecting the elevated tanks and the images are collected for detecting defects such as cracks. To automatically detect and segment the defect in images, Mask Regional Convolutional Neural Network (Mask-RCNN) the latest convolution neural network model is trained with the real-world infrastructure inspection images. The trained model has been applied to crack detection and segmentation for a water tower of 50 meters height and storage of 500 m3. The images are used to construct a 3D mesh model by photogrammetry technology. The 3D model with annotated cracks enables intuitive visualization and quantitative assessment of 1704 detected cracks, which are evaluated in range of 2 mm to 10 mm wide with total crack length of 77.6 m and total crack area of 0.28 m2. [ABSTRACT FROM AUTHOR]

A polystyrene (PS) microfluidic chip with Cantor fractal structure is fabricated using CO2 laser system. We study the effects of laser power and laser traverse speed on the depth, width of PS microchannels. Laser power was set from 6 to 14 W and laser traverse speed was set from 6 to 10 mm/s in the experiments. A number of experiments were carried out to find the appropriate parameters in the range of the set parameters for the CO2 laser machining of microchannels. Hot pressing bonding technology was used to integrate the PS cover plate and the PS substrate. The work shows that CO2 laser processing is a low cost, fast, convenient and high precision microfluidic chip processing method. The microfluidic chip with Cantor fractal made of PS material can achieve better mixing effect. Using our method, we can process a minimum width of 20 µm and a minimum depth of 15 µm microchannel, which provides effective help to the micron level microchannels that we processed. [ABSTRACT FROM AUTHOR]

Biological entities such as fungi in stored grain evolve and interact with the environment in similar fashions as physical fields. An experiment was conducted to study the behavior of the biological field of fungi in stored grain, as well as the interactions between the biological field of fungi and the physical fields of temperature and moisture. A framework of the biological field is presented to describe biological systems in which multiple biological entities co-exist and interact among themselves and with the surrounding environment. The proposed biological field describes the spatio-temporal distribution of a biological entity and its ability of influencing (or being influenced by) the surrounding biotic and abiotic entities through exchange of energy, matter, and/or information. The strength of a biological field of fungi was quantified as the rate of energy conversion by fungi from grain starch to heat. The experimental data showed that the strength of biological field of fungi in stored grain varied in both space and time, with the maximum field strength of 120–133 W m−3 occurred at the location where the biological field of fungi interacted strongly with the temperature and moisture fields. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization, and storage may lead to mechanical degradation of the subsurface reservoir from fluid‐rock interaction, which could lead to wellbore instability or reservoir compaction. To better understand potential relationship between mechanical degradation with various carbonate cement textures and compositions in sandstone reservoirs, six flow‐through experiments were conducted. Formation water (TDS = 5,390 mg/L) enriched with CO2 flowed through two types of Pennsylvanian Morrow B Sandstone: an ankerite‐siderite‐cemented sandstone (disseminated cement texture) and a calcite‐cemented sandstone (poikilotopic cement texture). The experiments produced little change in permeability in the ankerite‐siderite‐cemented sandstone, but permeability increased up to more than 1 order of magnitude in the calcite‐cemented sandstone. Ultrasonic measurements and cylinder‐splitting tests (also known as Brazilian tests) suggested negligible mechanical degradation of the ankerite‐siderite‐cemented sandstone. Variable changes, with significant mechanical degradation in the static moduli, were observed in the calcite‐cemented sandstone. Thus, dissolution of the disseminated ankerite‐siderite cement (0.28–0.30%) had minimal impact on modifying the flow network and the mechanical integrity of the sandstone, whereas dissolution of the poikilotopic calcite cement (0.89–1.13%, quantified with fluid chemistry and visualized with X‐ray microcomputed tomography) impacted the mechanical strength of the sandstone by disconnecting framework grains. With the high water‐to‐rock mass ratios (7.3–8.2) and number of pore volumes (147–675) employed in these experiments, potential risks are most relevant to regions near injection wells. Ultimately, the chemo‐mechanical effects induced by CO2 injection are strongly influenced by the cement texture and composition and the burial history of the reservoir rock. Plain Language Summary: Carbon capture, utilization, and storage is an approach that involves capturing CO2 (carbon dioxide) produced from industrial processes and storing it into sandstone reservoirs (a porous sedimentary rock) to reduce CO2 emissions and mitigate global climate change. This leads to complex subsurface processes, which can change physical, chemical, and mechanical properties in the reservoirs. To quantify these coupled processes, we conducted flow‐through experiments (injecting CO2‐rich fluid into sandstone plugs) on two types of sandstones with different cements. We monitored for flow and chemistry changes, performed 2‐D and 3‐D image analyses, and conducted rock mechanics experiments. The CO2‐induced dissolution of the ankerite‐siderite cement dispersing in the pore space had minimal impact on changing the flow network and the mechanical properties of the sandstone, whereas dissolution of the calcite cement completely filling the pore space impacted the mechanical properties of the sandstone by disconnecting framework grains. With high water‐to‐rock mass ratios and the compacted sandstone samples employed in the experiments, the potential risks are most relevant to regions near injection wells. Ultimately, the CO2‐induced mechanical weakening of sandstone is strongly influenced by the cement texture and composition, as well as the burial history of the reservoir rock. Key Points: CO2‐induced dissolution in disseminated ankerite‐siderite‐cemented sandstone yields little change in permeability and mechanical propertiesCO2‐induced dissolution in poikilotopic calcite‐cemented sandstone yields little to significant permeability and mechanical property changesChemo‐mechanical degradation is highly controlled by the cement texture and composition, as well as the burial history of the rock [ABSTRACT FROM AUTHOR]

We propose a new scheme for compression of ultrashort laser pulses enabled by Near-Forward Raman Amplification (NFRA) in plasma. In contrast to traditional forward Raman amplification in plasma, the seed pulse in NFRA propagates faster than the pump through manipulation of the spatiotemporal properties of the pump beam. A "π-pulse" solution similar to that of stimulated Raman backscattering amplification is obtained, indicating that NFRA can be used for compression of ultrashort laser pulses. NFRA is numerically demonstrated with a 2D simulation using a front-tilt near-forward pump pulse. [ABSTRACT FROM AUTHOR]

Laser micro-hole processing has been widely used in industry. Many laser processing parameters can affect the processing results. The relationship between the geometrical shapes of micro-holes and the laser processing parameters has not been determined accurately. In this paper, experiments on the femtosecond laser drilling of the nickel-base single-crystal super-alloy (DD6) materials were conducted to determine the relationship between the parameters, such as the laser single-pulse energy, rotation rate, and downward focus rate, and the geometrical characteristics of the micro-holes, such as the diameter, and roundness. A group of orthogonal experiments were conducted to determine the effects of the comprehensive influencing factors on the geometrical characteristics of the micro-holes. After the experiments were conducted and analysed, the experimental results were modelled by a backpropagation neural network, and the mapping relationship between the laser parameters and the geometrical morphologies of the micro-holes was constructed. The model established by the backpropagation neural network could obtain accurate prediction results, and the predictions of the diameters of the micro-holes were better than those of the roundness. [ABSTRACT FROM AUTHOR]

Background: Humanin has reportedly been expressed in testis and spermatozoa, but no study has yet reported its presence in human seminal plasma (SP). Objective: The aim of this study was to investigate the presence of humanin in human SP and to determine the correlation between humanin levels in SP/spermatozoa and sperm quality. Materials and methods: Semen samples for SP/sperm humanin level measurement were collected from 164 patients who attended our andrology clinic for fertility evaluation. The localization of humanin in spermatozoa was evaluated using an immunofluorescence method, and SP/sperm humanin levels were measured with ELISA. Correlations between SP/sperm humanin levels and sperm parameters were analyzed. Results: Humanin was expressed in the midpiece of the spermatozoa. Humanin concentrations in the SP ranged from 24.4 to 285.1 pg/mL, with a median of 89.7 pg/mL. The SP humanin concentrations in patients with normospermia were significantly higher than those in patients with oligospermia (p < 0.001), asthenospermia (p = 0.002), and oligoasthenospermia (p < 0.001). Spearman analysis showed a positive and significant correlation between SP humanin concentration and sperm concentration (r = 0.75, p < 0.001), and progressive sperm motility (r = 0.29, p < 0.001). Sperm humanin level was significantly and positively associated with progressive sperm motility (r = 0.70, p < 0.001). In addition, a significantly higher level of humanin was found in swim‐up spermatozoa than in non‐swim‐up spermatozoa (p = 0.03). Conclusions: Seminal plasma and sperm humanin levels were significantly and positively correlated with sperm quality, especially sperm motility. Further studies of the origin of SP humanin and its role in spermatogenesis should be conducted. [ABSTRACT FROM AUTHOR]

In this research, we investigate in-depth the nonlinear energy transmission phenomenon in a metastable modular metastructure and develop efficient tools for the design of such systems. Previous studies on a one-dimensional (1D) reconfigurable metastable modular chain uncover that when the driving frequency is within the stopband of the periodic structure, there exists a threshold input amplitude, beyond which sudden increase in the energy transmission can be observed. This onset of transmission is caused by nonlinear instability and is known as supratransmission. Due to spatial asymmetry of strategically configured constituents, such transmission thresholds could shift considerably when the structure is excited from different ends and therefore enabling the non-reciprocal energy transmission. This one-way propagation characteristic can be adaptable via reconfiguring the metastable modular system. In this new study, we build upon these findings and advance the state of the art by (a) exploring the different mechanisms that are able to activate the onset of supratransmission and their implications on wave energy transmission potential, and (b) developing an effective design tool - a localized nonlinear-linear model combined with harmonic balancing and transfer matrix analyses to analytically and efficiently predict the critical threshold amplitude of the metastable modular chain. These investigations provide important new understandings of the rich and intricate dynamics achievable by nonlinearity, asymmetry, and metastability, and create opportunities to accomplish adaptable non-reciprocal wave energy transmission. [ABSTRACT FROM AUTHOR]

The aim of present paper is to study a constrained programming with generalized α-univex fuzzy mappings. In this paper we introduce the concepts of α-univex, α-preunivex, pseudo α-univex and α-unicave fuzzy mappings, and we discover that α-univex fuzzy mappings are more general than univex fuzzy mappings. Then, we discuss the relationships of generalized α-univex fuzzy mappings and get some properties. In the last, we derive necessary and sufficient Karush-Kuhn-Tucker conditions and its dual problems with generalized di erentiable α-univex fuzzy mappings for fuzzy constrained programming problem. [ABSTRACT FROM AUTHOR]

The efficiency transfer from the pump to the seed of stimulated Raman backscattering in plasma was optimized at a pump intensity below 1014 W/cm2. Two ways were employed to obtain high-quality but low-intensity pump beams. First, the pump focus was moved away from the plasma entrance to optimize guiding the uniform part of the beam in the plasma channel. The seed was amplified from 50 μJ to 1.1 mJ after 2-mm interaction, with an effective Raman transfer efficiency over 4.7%. Second, an aperture was set to make the pump focus pass through the plasma channel. An output seed energy of 1.02 mJ was obtained when the pump energy decreased to 20 mJ, showing a transfer efficiency of 5.1%. The experimental results indicate that the transfer efficiency may be mainly suppressed by plasma heating but not spontaneous Raman scattering. [ABSTRACT FROM AUTHOR]

Background: Older age has long been linked to risk of diverticulitis, but the epidemiology is seldom described for a national population. The aim of this study was to investigate age- and gender differences in incidence, temporal trends, lifetime risk and prevalence related to acute diverticulitis hospitalisations in New Zealand. Methods: Records of all hospitalisations with diverticulitis the primary diagnosis were obtained from the Ministry of Health for the period 2000–2015. The first acute diverticulitis admission recorded for an individual was taken as an incident event; all others were classified as recurrent. Trends in age- and sex-specific and age-standardised incidence rates are described, and lifetime risk and prevalence estimated. Results: Over the 16 years from 2000 to 2015, 37,234 acute hospitalisations for diverticulitis were recorded in 28,329 people aged 30 + years (median = 66 years). Rates of incident hospitalisations rose with age, from 5/10,000 person-years at age 50–54 years to 19/10,000py by age 80–84 years. Rates for women were lower than men before age 55 years, but higher thereafter. Age-standardised rates rose 0.2/10,000py annually, but approximately doubled among men aged < 50 years. Lifetime risk was estimated at over 5%, with the prevalence pool rising to over 1.5% of the population aged 30+ in 2030. Conclusions: Rapid increases in diverticulitis admissions among young men since 2000 correspond with increases reported elsewhere but remain unexplained; notably young women follow similar trends 5–10 years later. Increasing incidence, combined with population ageing, adds urgency to explain diverticular formation, to understand factors that trigger or provoke their inflammation/infection, and to clarify treatment and (self-)management pathways. [ABSTRACT FROM AUTHOR]

CO2 laser processing technology is a low cost, simple and efficient processing method for fabrication of microfluidic chip on Poly(methyl methacrylate) (PMMA). In this paper, we study the influence of low power and low speed of laser processing on the PMMA microchannel. Laser power was set from 5 to 15 W and laser traverse is set from 6 to 10 mm/s in the experiment. Though experiment results to compare the influence of laser processing parameters on the depth and width of microchannel. The suitable parameters are selected to process the microchannel on the PMMA plate. Finally, a PMMA microfluidic chip with Cantor fractal structure is fabricated by the method of hot pressing bonding. The experiment results show that CO2 laser processing technology is a low cost, flexible and convenient method in the microfluidic chip processing. [ABSTRACT FROM AUTHOR]

In this paper we report on the realization of magnetic field-induced martensitic phase transformation in Mn-rich Heusler alloy Mn2Ni1.36Sn0.32Co0.32. The saturation magnetization of the austenite reached 111 emu/g at 70 kOe, which decreased rapidly to 8 emu/g upon transforming to martensite. This is attributed to the crystallographic distortion from cubic structure to tetragonal structure with c/a > 1, turning the Mn moments at B sites and D sites from parallel alignment to antiparallel alignment. A large magnetoresistance of 40% was observed through the field-induced transformation. The increase of conduction electrons accompanying this field-induced martensitic transformation is estimated to be 67%. These intriguing properties render the alloy a good candidate for applications in smart devices. [ABSTRACT FROM AUTHOR]

Bond distances, vibrational frequencies, electron affinities, ionization potentials, dissociation energies, and dipole moments of the title molecules in neutral, positively, and negatively charged ions were studied using the density functional method. Ground state was assigned for each species. The bonding patterns were analyzed and compared with both the available data and across the series. It was found that besides an ionic component, covalent bonds are formed between the metal s,d orbitals and the silicon 3p orbital. The covalent character increases from ScSi (YSi) to NiSi (PdSi) for 3d (4d) metal monosilicides, then decreases. For 5d metal monosilicides, the covalent character increases from LaSi to OsSi, then decreases. For the dissociation of cations, the dissociation channel depends on the magnitude of the ionization potential between metal and silicon. If the ionization potential of the metal is smaller than that of silicon, channel MSi+→M++Si is favored. Otherwise, MSi+→M+Si+ will be favored. A similar behavior was observed for anions, in which the dissociation channel depends on the magnitude of electron affinity. [ABSTRACT FROM AUTHOR]

Covering the solid lattice with a finite-element mesh produces a coarse-grained system of mesh nodes as pseudoatoms interacting through an effective potential energy that depends implicitly on the thermodynamic state. Use of the pseudoatomic Hamiltonian in a Monte Carlo simulation of the two-dimensional Lennard-Jones crystal yields equilibrium thermomechanical properties (e.g., isotropic stress) in excellent agreement with “exact” fully atomistic results. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]