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Seafloor ambient noise in the Arctic Ocean is related to sea ice. The characteristics of low‐frequency seafloor ambient noise (<10 Hz) in the northern Chukchi Sea have rarely been reported. Here, we investigated the seafloor ambient noise recorded using ocean‐bottom seismometers in the northern Chukchi Sea under four different sea ice‐concentration periods from 3 to 23 August 2020, in the 11th Chinese National Arctic Research Expedition. The causes and mechanisms of the changes in seafloor ambient noise that correspond to the variation in sea ice concentration were discussed. The energy of infragravity waves and primary microseisms is weak compared with other oceans. Combined with the analysis of land station, we argue that the variations in sea ice extent have little effect on the energy of the primary microseisms and infragravity waves. The power of secondary microseisms is growth with the loss of sea ice and is influenced by storms. We find that a high concentration of sea ice can impede the process of storm‐sea surface interaction, which in turn affects the power of microseisms inspired by storm. [ABSTRACT FROM AUTHOR]

Amidst global climate change and unsustainable human exploitation of water resources, water has emerged as a critical factor constraining global agricultural food production and ecological environments. Particularly in agricultural powerhouses like China, irrigation water accounts for a significant portion of freshwater resource utilization. However, the inefficiency of irrigation water usage has become a weak link in water resource management. To better assess irrigation water efficiency, an accurate estimation of regional irrigated areas is urgently needed. This study proposes a method for identifying actual irrigated areas based on remote sensing-derived evapotranspiration (ET) to address the challenge of accurately interpreting irrigated areas in tropical regions. Using Yunnan Province's Yuanmou irrigation district as a case study, this research combined ground monitoring data and remote sensing data to identify actual irrigated areas through ET inversion and downscaling methods using the Penman–Monteith–Leuning (PML) model. In 2023, the total irrigated area interpreted from remote sensing in the study area was approximately 15,000 hm2, with a comparison against validation points revealing an extraction error of 16%. The small error indicates that this method can effectively enhance the reliability of monitoring actual irrigated areas, thus providing valuable data support for agricultural irrigation water management. [ABSTRACT FROM AUTHOR]

Civilian fusion demands structural materials that can withstand the harsh environments imposed inside fusion plasma reactors. The structural materials often transmute under 14.1 MeV fast neutrons, producing helium (He), which embrittles the grain boundary (GB) network. Here, it is shown that neutron‐friendly and mechanically strong nano‐phases with atomic‐scale free volume can have low He‐embedding energy Eemb${\mathcal{E}}_{\mathrm{emb}}$ and >10 at.% He‐absorbing capacity, and can be especially advantageous for soaking up He on top of resisting radiation damage and creep, provided they have thermodynamic compatibility with the matrix phase, satisfactory equilibrium wetting angle, as well as a high enough melting point. The preliminary experimental demonstration proves that Eemb${\mathcal{E}}_{\mathrm{emb}}$ is a good ab initio predictor of He shielding potency in nano‐heterophase materials, and thus, Eemb${\mathcal{E}}_{\mathrm{emb}}$ is used as a key feature for computational screening. In this context, a list of viable compounds expected to be good He‐absorbing nano‐phases is presented, taking into account Eemb${\mathcal{E}}_{\mathrm{emb}}$, the neutron absorption and activation cross‐sections, the elastic moduli, melting temperature, the thermodynamic compatibility, and the equilbrium wetting angle of the nano‐phases with the Fe matrix as an example. [ABSTRACT FROM AUTHOR]

A novel class of secondary amines with long chains containing ether bonds were synthesized by a three-step protection–etherification–deprotection process from diethanolamine. The optimum reaction conditions were examined. This method has the advantages of simplicity, low cost, and high yield. Furthermore, some new downstream products (diglycolamides) were prepared from the ether-containing long-chain secondary amines as reactants, and their loading capacities in extractions of several metal ions were evaluated. [ABSTRACT FROM AUTHOR]

Most identification methods for marine oil spills rely on single-dimensional chemical fingerprinting that is ineffective for weathered oil. A quantitative identification method is proposed in this study based upon multi-dimensional chemical fingerprinting composed of diagnostic ratios, wavelet coefficient, and the Ni/V. Twenty oil samples were used including 6 marine fuels, 7 Middle Eastern crude oils, and 7 non-Middle East crude oils. Diagnostic ratios were discussed using partial least square analysis, and fluorescence spectra were analyzed by db7 wavelet basis of 6-layers in the discrete wavelet transform. The first principal component and the wavelet coefficient at 354 ± 2 nm were combined with Ni/V and optimized by an exhaustive method as variables to establish the Fisher discriminant model. The developed model had 100% accuracy for modeled oil samples and for non-modeled crude oil before and after weathering, respectively, with 83.3% accuracy for non-modeled or short-term weathered marine fuel. The accuracy was 3% higher than reported in the literature. [ABSTRACT FROM AUTHOR]

Quantum anomalous Hall (QAH) effect generates quantized electric charge Hall conductance without external magnetic field. It requires both nontrivial band topology and time‐reversal symmetry (TRS) breaking. In most cases, one can break the TRS of time‐reversal invariant topological materials to yield QAH effect, which is essentially a topological phase transition. However, conventional topological phase transition induced by external field/stimulus usually needs a route along which the bandgap closes and reopens. Hence, the transition occurs only when the magnitude of field/stimulus is larger than a critical value. In this work the authors propose that using gapless systems, the transition can happen at an arbitrarily weak (but finite) external field strength. For such an unconventional topological phase transition, the bandgap closing is guaranteed by bulk‐edge correspondence and symmetries, while the bandgap reopening is induced by external fields. This concept is demonstrated on the 2D surface states of 3D topological insulators like Bi2Se3, which become 2D QAH insulators once a circularly polarized light is turned on, according to the Floquet time crystal theory. The sign of quantized Chern number can be controlled via the chirality of the light. This provides a convenient and dynamic approach to trigger topological phase transitions and create QAH insulators. [ABSTRACT FROM AUTHOR]

This paper shows how terahertz light can drive ultrafast topological phase transitions in monolayer transition metal dichalcogenides (TMDs). The phase transition is induced by the light interaction with both electron and phonon subsystems in the material. The mechanism of such a phase transition is formulated by thermodynamics theory: the Gibbs free energy landscape can be effectively modulated under light, and the relative stability between different (meta‐)stable phases can be switched. This mechanism is applied to TMDs and reversible phase transitions between the topologically trivial 2H and nontrivial 1T′ phases are predicted, providing appropriate light frequency, polarization, and intensity are applied. The large energy barrier on the martensitic transformation path can be significantly reduced, yielding a small energy barrier phase transition with fast kinetics. Compared with other phase transition schemes, light illumination has great advantages, such as its non‐contact nature and easy tunability. The reversible topological phase transition can be applicable in high‐resolution fast data storage and in‐memory computing devices. [ABSTRACT FROM AUTHOR]

Purpose This study was aimed to discover the combined effects of single nucleotide polymorphisms (SNPs) within the C-reactive protein (CRP) gene and potential environmental factors on the risk and prognosis for diabetic foot osteomyelitis (DFO). Methods A total of 1734 diabetes mellitus patients, 681 with DFO and 1053 without DFO, were successfully recruited, as well as 1261 healthy control individuals. Participants data were recorded regarding age, gender, smoking and drinking history, body mass index (BMI), hypertension, cacosmia, and ulceration. A total of 11 SNPs within the CRP gene were designated for exploration, by logistic regression analyses, of how they might interact with environmental factors to affect susceptibility to DFO. Results Frequencies of smoking and drinking, and incidence of hypertension, cacosmia, or ulceration displayed marked differences (all P <0.05) between DFO and non-DFO patients. Furthermore, allele G of rs11265260 (A>G), allele G of rs1800947 (C>G), and allele T of rs3093059 (T>C) and rs1130864 (C>T) exhibited a trend to increase risk of DFO (all P <0.05). Allele G of rs11265260 (A>G), allele G of rs1800947 (C>G) and rs3093068 (G>C), and allele T of rs1130864 (C>T) were significant predictors of poor prognosis among DFO patients (P <0.05). In addition, genotypes of rs11265260 (i.e., GG and AG), rs1800947 (i.e., CG and GG), rs3093059 (i.e., TT) and rs113084 (i.e., CT and TT) amplified the influence of smoking, alcohol consumption, cacosmia, and ulceration on progression from non-DFO to DFO (all γ >1). Conclusion Genetic mutations within CRP functioned interactively with external factors to affect DFO risk. [ABSTRACT FROM AUTHOR]

Most Penman-Monteith-Leuning (PML) evapotranspiration (ET) modeling studies are dominated by consideration of meteorological, energy, and land use information, etc., but the dynamic coupling of soil moisture content (SM), especially in terms of improving accuracy through assimilation, lacks sufficient attention. This paper proposes a research framework for the dynamic coupling simulation of PML model and SM based on data assimilation, i.e., the remote sensing monitored SM is combined with soil evaporation of PML to obtain high-precision time-continuous SM data through data assimilation; simultaneously, dynamical soil evaporation coefficients are generated based on the assimilated SM to improve the simulation accuracy of the PML model. The new scheme was validated at a typical irrigation zone in north China and showed obvious improvements in both SM and ET simulations. Moreover, the effect of the assimilation of SM on the simulation accuracy of ET for different crop growth periods is further analyzed. This research provides a new idea for the coupling simulation of the SM and PML models. [ABSTRACT FROM AUTHOR]

The Okinawa Trough (OT) is characterized by high heat flow anomalies up to 10,000 mW/m2 (especially in the middle area), which is rarely seen in heat flow research all over the world. The genesis of the high heat flow anomaly is probably related to mantle upwelling. However, the deep genesis is yet to be studied. We used heat flow values collected from the Global Heat Flow Database to calibrate the locations of high heat flow anomalies. Gravity data were used to calculate the residual geoid and interlayer geoid anomalies, which can help in characterizing the morphology of mantle upwelling beneath the OT. Earthquake hypocenter distribution maps were presented to show the position of the Philippine Sea Plate beneath the OT. According to P-wave tomography profile and previous research, we discussed the deep genesis of the high heat flow anomaly and proposed a preliminary model to explain the process. We suggest that the deep mantle upwelling, probably from a depth of −1200 km, enters the upper mantle through the front of the subducted Pacific plate. The deep mantle upwelling converges with the molten mantle flow caused by the fluid from the dehydration of the Pacific Plate and the Philippine Sea Plate. Two mantle upwelling branches were revealed to feed the southern OT (SOT) and Changbai Volcano, and the mantle upwelling under the middle OT (MOT) was the second branch from the mantle upwelling branch under the SOT. The MOT should be more influenced by mantle upwelling from deep sources with extremely high temperatures. • Deep mantle upwelling enters the upper mantle through the front of the subducted Pacific plate. • Two mantle upwelling branches from deep source were revealed to feed the Okinawa Trough and Changbai Volcano. • The genesis of the high heat flow anomaly in the middle Okinawa Trough is probably related to deep mantle upwelling. [ABSTRACT FROM AUTHOR]

A Bi 2 Te 3 -based thermoelectric generator (TEG) system cooled by heat radiation fin (HRF) applies to most scenarios of low-temperature power generation and waste heat recovery, while the high performance of the TEG system requires the precise design of the structure. Here we developed a theoretical model to simulate the thermal-electric coupling of the TEG system and analyzed the Bi 2 Te 3 -based TEG system with the aid of numerical and experimental methods. Results show that the increase in height of TEG not only improves the conversion efficiency but leads to a peak value of output power, which is much different from the traditional view that the output power solely decreases with the increase of height of TEG. Compared to the thickness of the fin, the height of the fin plays an essential role in optimizing the performance of TEG. By adding an electrical fan to improve the heat exchange coefficient, the net output power is doubled and the net conversion efficiency is improved by more than 80%. Besides, the structure of the TEG system is designed for different material parameters via the theoretical method. We anticipate that our results will guide the design and optimization of the TEG system. • Theoretical model simulates thermal-electric fields of TEG system. • Adjusting height of TEG leads to a peak value of output power. • Height of fin plays major role in optimizing performance of TEG system. • Additional fan doubles net output power and greatly improves efficiency. • Bi 2 Te 3 is proven by theoretical results to be a better choice for TEG system. [ABSTRACT FROM AUTHOR]

The effect of quantum gravity can bring a tiny light speed variation which is detectable through energetic photons propagating from gamma ray bursts (GRBs) to an observer such as the space observatory. Through an analysis of the energetic photon data of the GRBs observed by the Fermi Gamma-ray Space Telescope (FGST), we reveal a surprising regularity of the observed time lags between photons of different energies with respect to the Lorentz violation factor due to the light speed energy dependence. Such regularity suggests a linear form correction of the light speed v ( E ) = c ( 1 − E / E LV ) , where E is the photon energy and E LV = ( 3.60 ± 0.26 ) × 10 17 GeV is the Lorentz violation scale measured by the energetic photon data of GRBs. The results support an energy dependence of the light speed in cosmological space. [ABSTRACT FROM AUTHOR]

The segmented structure can effectively improve the performance of a thermoelectric generator (TEG), but the interfacial thermal stress between adjacent segments seriously threatens the reliability of segmented TEGs. Noticing this, we investigate the mechanical performance of a segmented TEG via theoretical and numerical methods. Results show that the structural stress depends on the ratio of cross-sectional areas between p- and n-type TE legs rather than the absolute cross-sectional areas, while the height ratio of different segments has a significant influence on structural stress. Different from structural stress, the thermal stress induced by unmatched thermal expansion between different segments increases rapidly with the increase of cross-sectional area, and can easily exceed 20% of the total interfacial stress. Besides, both the conversion efficiency and interfacial stress can be optimized by adjusting the ratio of cross-sectional areas. Our results provide the theoretical basis and guidance in the design of segmented TEGs. [ABSTRACT FROM AUTHOR]

It is postulated in Einstein's relativity that the speed of light in vacuum is a constant for all observers. However, the effect of quantum gravity could bring an energy dependence of light speed. Even a tiny speed variation, when amplified by the cosmological distance, may be revealed by the observed time lags between photons with different energies from astrophysical sources. From the newly detected long gamma ray burst GRB 160509A, we find evidence to support the prediction for a linear form modification of light speed in cosmological space. [ABSTRACT FROM AUTHOR]

Alternaria blotch, Brown spot, Mosaic, Grey spot, and Rust are 5 common apple leaf diseases that severely impact apple production and quality. At present, although many CNN methods have been proposed for apple leaf diseases, there are still lack of apple leaf disease detection models that can be applied on mobile devices, which limits their application in practical production. This paper proposes a light-weight CNN model that can be deployed on mobile devices to detect apple leaf diseases in real time. First, a dataset of apple leaf diseases composed of simple background images and complex background images, which is called AppleDisease5, is constructed via data augmentation technology and data annotation technology. Then a basic module called MEAN block(Mobile End AppleNet block) is proposed to increase the detection speed and reduce model's size by reconstructing the common 3 × 3 convolution. Meanwhile, the Apple-Inception module is built by introducing GoogLeNet's Inception module and replacing all 3 × 3 convolution kernels with MEAN block in Inception. Finally, a new apple leaf disease detection model, MEAN-SSD(Mobile End AppleNet based SSD algorithm), is built by using the MEAN block and Apple-Inception module. The experiment results show that MEAN-SSD can achieve the detection performance of 83.12% mAP and a speed of 12.53 FPS, which illustrates that the novel MEAN-SSD model can efficiently and accurately detect 5 common apple leaf diseases on mobile devices. [ABSTRACT FROM AUTHOR]

In article number 2003832 by Jian Zhou, Ju Li, and co-workers, optomechanical theory is derived and applied to predict terahertz optics driven ultrafast and reversible topological phase transitions in transition metal dichalcogenide monolayers, which is a damage-free and non-contacting approach that compensates other strategies. The cover displays such a novel optical strategy to trigger a thermal topological phase transition. [Extracted from the article]

Objective: To determine if preoperative albumin-alkaline phosphatase ratio (AAPR) is predictive of clinical outcomes in patients with degenerative lumbar diseases undergoing lumbar fusion. Method: 326 patients undergoing posterior lumbar decompression and fusion were retrospectively analyzed. The cumulative grade was calculated by summing the Pfirrmann grades of all lumbar discs. Grouping was based on the 50th percentile of cumulative grade. The relationship between AAPR, intervertebral disc degeneration (IDD) severity, and fusion rate was explored using correlation analyses and logistic regression models. Meanwhile, the ROC curve evaluated the discrimination ability of AAPR in predicting severe degeneration and non-fusion. Results: High AAPR levels were significantly negatively correlated with severe degeneration and non-fusion rate. A multivariate binary logistic analysis revealed that high preoperative AAPR was an independent predictor of severe degeneration and postoperative non-fusion (OR: 0.114; 95% CI: 0.027–0.482; p = 0.003; OR: 0.003; 95% CI: 0.0003–0.022; p < 0.001). The models showed excellent discrimination and calibration. The areas under the curve (AUC) of severe degeneration and non-fusion identified by AAPR were 0.635 and 0.643. Conclusion: The AAPR can help predict the severity of disc degeneration and the likelihood of non-fusion. [ABSTRACT FROM AUTHOR]

The precise controllability of the Fermi level is a critical aspect of quantum materials. For topological Weyl semimetals, there is a pressing need to fine-tune the Fermi level to the Weyl nodes and unlock exotic electronic and optoelectronic effects associated with the divergent Berry curvature. However, in contrast to two-dimensional materials, where the Fermi level can be controlled through various techniques, the situation for bulk crystals beyond laborious chemical doping poses significant challenges. Here, we report the milli-electron-volt (meV) level ultra-fine-tuning of the Fermi level of bulk topological Weyl semimetal tantalum phosphide using accelerator-based high-energy hydrogen implantation and theory-driven planning. By calculating the desired carrier density and controlling the accelerator profiles, the Fermi level can be experimentally fine-tuned from 5 meV below, to 3.8 meV below, to 3.2 meV above the Weyl nodes. High-resolution transmission electron microscopy reveals the crystalline structure is largely maintained under irradiation, while electrical transport indicates that Weyl nodes are preserved and carrier mobility is also largely retained. Our work demonstrates the viability of this generic approach to tune the Fermi level in semimetal systems and could serve to achieve property fine-tuning for other bulk quantum materials with ultrahigh precision. [ABSTRACT FROM AUTHOR]

Diffusion in alloys is an important class of atomic processes. However, atomistic simulations of diffusion in chemically complex solids are confronted with the timescale problem: the accessible simulation time is usually far shorter than that of experimental interest. In this work, long‐timescale simulation methods are developed using reinforcement learning (RL) that extends simulation capability to match the duration of experimental interest. Two special limits, RL transition kinetics simulator (TKS) and RL low‐energy states sampler (LSS), are implemented and explained in detail, while the meaning of general RL are also discussed. As a testbed, hydrogen diffusivity is computed using RL TKS in pure metals and a medium entropy alloy, CrCoNi, and compared with experiments. The algorithm can produce counter‐intuitive hydrogen‐vacancy cooperative motion. We also demonstrate that RL LSS can accelerate the sampling of low‐energy configurations compared to the Metropolis–Hastings algorithm, using hydrogen migration to copper (111) surface as an example. [ABSTRACT FROM AUTHOR]

Abstract: This study addresses the problem of short UWB (ultra‐wide band) outages in a UWB/IMU (inertial measurement unit) integrated navigation system. UWB outages may occur due to non‐line‐of‐sight between the UWB radios. To mitigate the errors during short UWB outages, we consider the special dynamics of the platform by adaptively applying constraints in the navigation filter. The application presented here is the navigation problem of the unexploded ordnances (UXOs) mapping platform. A UXO platform moves straight or performs turns or stops; these are the three dynamic states with pre‐defined constraints. Two neural networks are examined to determine the current dynamic state based on IMU data. Tests on open‐sky and canopied areas were carried out for the performance assessment. The networks were trained on the open‐sky dataset, and then tested on the canopied area. The detected improvement of the proposed solution is 10–30% (10–15 cm) for 5–10 s long outages. Copyright © 2018 Institute of Navigation [ABSTRACT FROM AUTHOR]

The existing researches for leaf area index (LAI)-based Penman–Monteith evapotranspiration (ET) model (PML) are mostly carried out at yearly scale and the analysis of effects of seasonal change and different underlying surface conditions on model parameters is scarce. This study emphasizes on the influences of seasonal change and diverse land surface conditions on ET by optimizing the sensitive parameters, namely soil evaporation coefficient f and maximum stomatal conductance gsx, with particle swarm algorithm. This analysis is based on the observations of eight flux stations in China. The model performance is reasonable with a best Pearson r of 0.87. The seasonal calibration results indicate parameters change evidently in different seasons and have obvious spatial heterogeneity. The seasonal calibration method has an obvious effect on improving the ET accuracy in spring, which is mostly influenced by regional temperature and relative humidity. This study further demonstrates the need to dynamically adjust model parameters over time with PML model for evapotranspiration simulations, rather than simply setting these parameters to constants depended on subsurface conditions such as land use type. [ABSTRACT FROM AUTHOR]

• In-situ performance of a thermoelectric generator in the core of a nuclear reactor. • Thermoelectric performance degrades under irradiation at low temperatures. • Significant recovery in performance under irradiation at high temperatures. • Operation at high temperature prevents unfavorable phase change. • Nanostructured thermoelectrics can provide stable power in the nuclear reactor core. Thermoelectric energy converters offer a promising solution to generate electrical power using heat in the nuclear reactor core. Despite significant improvements in thermoelectric efficiency of nanostructured materials, the performance of these advanced materials has yet to be demonstrated in the harsh radiation environment of a reactor core. Herein, we demonstrate a thermoelectric generator (TEG) made from nanostructured bulk half-Heusler (HH) materials generating stable electrical power density > 1140 W/m2 after 30 days in the MIT Nuclear Research Reactor under an unprecedented fast-neutron (>1 MeV) fluence of 1.5 × 1020 n/cm2. Despite an initial degradation due to irradiation damage when operating under relatively low temperatures, our TEG showed a 20-fold increase in power output when operating under high temperature due to in-situ annealing and resulting thermoelectric property recovery. First-principles modeling indicates that a chemically disordered metallic phase was formed under irradiation at lower temperatures, resulting in a drastic degradation in thermoelectric properties, while at sufficiently high temperatures the system returned to the initial chemically ordered HH phase and the thermoelectric properties recovered. Transmission electron microscopy and electron diffraction demonstrated that the chemically disordered phase was formed upon ion irradiation, confirming the prediction from first-principles simulations. The results suggest that with proper control over the TEG operating temperatures, the nanostructured bulk TEGs could produce stable electrical power and operate indefinitely in the core of a nuclear reactor. [ABSTRACT FROM AUTHOR]

Fusion power holds promise as an ultimate energy source. However, achieving true sustainability in fusion energy requires addressing the embrittlement of polycrystalline materials in fusion reactors caused by helium, which leads to premature failure, often within a year. Here we experimentally demonstrate that nanodispersoids with constitutional vacancy-like atomic-scale free volume can securely store helium, not only at the matrix-dispersoid interface but also within their bulk lattices, which suggests their effectiveness in delaying critical helium damage of the polycrystalline matrix. The selected model nano-heterophase, fayalite Fe 2 SiO 4 , possesses moderately strong lattice sinks for helium while undergoing lattice distortions upon helium absorption. These distortions cause observable changes in peak intensities of X-ray diffraction (XRD) patterns, distinct from changes resulting from other factors like radiation damage. By comparing grazing incidence XRD patterns with ab initio computed patterns, we show that such nano-heterophases can store up to ∼10 at% helium within their bulk lattice, forming a "helide compound." Incorporating just 1 vol% of Fe 2 SiO 4 reduces helium bubble size and number density by >20 % and >50 %, respectively. These findings suggest that 1–2 vol% of appropriate nano-heterophases can accommodate a few thousand appm of bulk helium, expected to be generated over a 10-year operational period. Nano-heterophases with constitutional vacancy-like atomic-scale free volume can divert and securely store helium within their "bulk lattices" over 10 at%, thereby significantly delaying the occurrence of critical helium damage in polycrystalline fusion structural materials. Incorporating 1–2 vol% of such nano-heterophases can effectively accommodate a few thousand appm of bulk helium, expected to be generated over a 10-year lifespan of civilian-fusion operation. [Display omitted] [ABSTRACT FROM AUTHOR]

Target rescue is an important application in the Internet of Things (IoT), and the direction-finding (DF) is an essential technology for the target rescue. The DF technology based on the phase comparison method is widely used in target rescue. However, due to the phase ambiguity, the phase comparison method is difficult to meet the needs of high precision DF. The long and short baseline method can eliminate the phase ambiguity in a certain angle range, but it cannot accurately direction in all directions. In this article, we propose a high precision DF method based on the multi-baseline and multi-antenna for target rescue. Firstly, the performance of the proposed method in eliminating the inhomogeneity and azimuth ambiguity in single antenna pairs is analyzed theoretically. Then, a measurement system configured of a cycle array with eight antennas is presented to validate the practicability of the proposed method. Finally, the measurement system is verified by experiments conducted in both anechoic chamber and the out-field scenarios. The experiment results demonstrate that the error of the proposed DF method is within 2° in the anechoic chamber and within 5° in out-field. Therefore, the proposed multi-baseline and multi-antenna method can be used for high precision DF for the target rescue. [ABSTRACT FROM AUTHOR]

The development of photonic integrated circuits would benefit from a wider selection of materials that can strongly control near-infrared (NIR) light. Transition metal dichalcogenides (TMDs) have been explored extensively for visible spectrum optoelectronics; the NIR properties of these layered materials have been less-studied. The measurement of optical constants is the foremost step to qualify TMDs for use in NIR photonics. Here, we measure the complex optical constants for select sulfide TMDs (bulk crystals of MoS2, TiS2, and ZrS2) via spectroscopic ellipsometry in the visible-to-NIR range. We find that the presence of native oxide layers (measured by transmission electron microscopy) significantly modifies the observed optical constants and need to be modeled to extract actual optical constants. We support our measurements with density functional theory calculations and further predict large refractive index contrast between different phases. We further propose that TMDs could find use as photonic phase-change materials, by designing alloys that are thermodynamically adjacent to phase boundaries between competing crystal structures, to realize martensitic (i.e., displacive, order–order) switching. [ABSTRACT FROM AUTHOR]

Coronary artery disease has one of the highest mortality rates in the country, and methods such as thrombolysis and percutaneous coronary intervention (PCI) can effectively improve symptoms and reduce mortality, but most patients still experience symptoms such as chest pain after PCI, which seriously affects their quality of life and increases the incidence of adverse cardiovascular events (myocardial ischaemia reperfusion injury, MIRI). MIRI has been shown to be closely associated with circadian rhythm disorders and mitochondrial dysfunction. Mitochondria are a key component in the maintenance of normal cardiac function, and new research shows that mitochondria have circadian properties. Traditional Chinese medicine (TCM), as a traditional therapeutic approach characterised by a holistic concept and evidence-based treatment, has significant advantages in the treatment of MIRI, and there is an interaction between the yin-yang theory of TCM and the circadian rhythm of Western medicine at various levels. This paper reviews the clinical evidence for the treatment of MIRI in TCM, basic experimental studies on the alleviation of MIRI by TCM through the regulation of mitochondria, the important role of circadian rhythms in the pathophysiology of MIRI, and the potential mechanisms by which TCM regulates mitochondrial circadian rhythms to alleviate MIRI through the regulation of the biological clock transcription factor. It is hoped that this review will provide new insights into the clinical management, basic research and development of drugs to treat MIRI. [Display omitted] • Traditional Chinese medicine(TCM) as a superior therapy for improving MIRI. • TCM ameliorates MIRI by protecting mitochondria. • Circadian rhythm disruption and mitochondrial damage as important pathogenic mechanisms in MIRI. • TCM is a potential therapeutic strategy to improve MIRI by regulating mitochondrial circadian rhythms. [ABSTRACT FROM AUTHOR]

An automated multi-plug filtration cleanup (m-PFC) method on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) extracts was developed. The automatic device was aimed to reduce labor-consuming manual operation workload in the cleanup steps. It could control the volume and the speed of pulling and pushing cycles accurately. In this work, m-PFC was based on multi-walled carbon nanotubes (MWCNTs) mixed with other sorbents and anhydrous magnesium sulfate (MgSO4) in a packed tip for analysis of pesticide multi-residues in crop commodities followed by liquid chromatography with tandem mass spectrometric (LC–MS/MS) detection. It was validated by analyzing 25 pesticides in six representative matrices spiked at two concentration levels of 10 and 100 μg/kg. Salts, sorbents, m-PFC procedure, automated pulling and pushing volume, automated pulling speed, and pushing speed for each matrix were optimized. After optimization, two general automated m-PFC methods were introduced to relatively simple (apple, citrus fruit, peanut) and relatively complex (spinach, leek, green tea) matrices. Spike recoveries were within 83 and 108% and 1–14% RSD for most analytes in the tested matrices. Matrix-matched calibrations were performed with the coefficients of determination >0.997 between concentration levels of 10 and 1000 μg/kg. The developed method was successfully applied to the determination of pesticide residues in market samples. [ABSTRACT FROM AUTHOR]

[Display omitted] Nickel-titanium (NiTi) shape memory alloys (SMA) are widely used, however simulating the martensitic transformation of NiTi from first principles remains challenging. In this work, we developed a neural network interatomic potential (NNIP) for near-equiatomic Ni-Ti system through active-learning based acquisitions of density functional theory (DFT) training data, which achieves state-of-the-art accuracy. Phonon dispersion and potential-of-mean-force calculations of the temperature-dependent free energy have been carried out. This NNIP predicts temperature-induced, stress-induced, and defect-induced martensitic transformations from atomic simulations, in significant agreement with experiments. The NNIP can directly simulate the superelasticity of NiTi nanowires, providing a tool to guide their design. [ABSTRACT FROM AUTHOR]

The extraction of Pd2+ with N,N -dialkyl-2-(3-(pyridine-2-yl)-1 H -pyrazole-1-yl) acetamide (A-C-PzPy) and N,N -dialkyl-3-(pyridine-2-yl)-1 H -pyrazole-1-carboxamide (A-PzPy) from HNO 3 medium, as well as the complexation of Pd2+ with A-C-PzPy were investigated. The use of tert-butyl benzene (TBB) as a diluent for A-C-PzPy offered significantly better extractability toward Pd2+, compared to that of A-PzPy. This study demonstrated strong extractability, high selectivity, high loading capacity, and fast extraction kinetics for DOct-C-PzPy toward Pd2+ from highly acidic HNO 3 solution (up to 5.0 mol/L). Slope analysis showed the formation of 1:1 type of extracted species of Pd2+ with DOct-C-PzPy ligand. The extraction was a spontaneous and endothermic process with increased entropy. The analyses of electrospray ionization mass spectrometry (ESI-MS), Fourier transform infrared (FT-IR) and UV–vis spectrophotometric titration revealed that the composition of the extracted neutral complex species was Pd(NO 3) 2 (DOct-C-PzPy). Combining the results of solvent extraction and complexation study, a neutral complexation extraction model is proposed. Furthermore, the stability constants (log β) for the complexation of Pd2+ with A-C-PzPy are also presented. [Display omitted] • DOct-C-PzPy exhibited high extractability and selectivity for Pd2+ in HNO 3 solution. • The composition of extraction complex was determined by MS, IR and UV–vis analyses. • The stability constants of Pd2+ complexes were obtained by UV–vis spectral titration. • A neutral extraction model of Pd2+ in HNO 3 solution by DOct-C-PzPy was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Et-Tol-DAPhen displayed strong extractability and excellent selectivity for Pd2+in HNO 3 solution. • The ratio of Pd2+ to the ligand in the extracted species was determined. • The single-crystal of Et-Tol-DAPhen·Pd(NO 3) 2 was obtained for the first time. • A neutral complexation extraction model was determined. The solvent extraction of Pd2+ in nitric acid solution by a phenanthroline-derived diamide ligand of N,N′ -diethyl- N,N′ -ditolyl-2,9-diamide-1,10-phenanthroline (Et-Tol-DAPhen) and the complexation between them were described. By using meta -nitrobenzotrifluoride (F-3) as a diluent, Et-Tol-DAPhen ligand extracted Pd2+ with strong extractability and excellent selectivity in comparison with traditional amine extractants Aliquat 336 nitrate and tri- n -octylamine. Job's method and mole ratio method suggested the formation of a 1:1 complex of Pd2+ with Et-Tol-DAPhen. The extraction was a spontaneous and exothermic process of decreased entropy. Furthermore, the analyses of Fourier transform infrared spectra (FT-IR), UV-vis titration, and single-crystal X-ray diffraction revealed that the composition of the extracted species was [Et-Tol-DAPhen·Pd(NO 3) 2 ]. Based on the results of solvent extraction and complexation study, a neutral complexation extraction model was proposed. Meanwhile, the stability constant for the complexation of Pd2+ with Et-Tol-DAPhen was also presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • A-PzPy showed good selectivity of Am3+ over Eu3+ without any lipophilic anion source. • A-PzPy could effectively separate Am3+ from Eu3+ at a wide molar acidity range. • The composition of complexes was determined by coordination study. • A neutral complexation extraction mechanism was determined. The synthesis, Eu3+ complexation, and selective solvent extraction of Am3+ over Eu3+ in nitric acid solution by 2-carboxamido-6-(1 H -pyrazol-3-yl)-pyridines (A-PzPy) ligands were described. Without the aid of any lipophilic anion source, A-PzPy ligands in methyl isobutyl ketone (MIBK) diluent demonstrated a more favorable affinity of Am3+ than Eu3+ at high acidity levels. Slope analysis showed the formation of 1:2 metal/ligand extracted species. The extraction was a spontaneous exothermic process. The analyses of fluorescence titration, Fourier transform infrared (FT-IR), Raman, time-resolved laser fluorescence spectrum (TRLFS), electrospray ionization mass spectrometry (ESI-MS), conductivity and microcalorimetric titration revealed that the composition of complex is [Eu(NO 3) 2 (H 2 O)∙2(Et- p -Tol-A-PzPy)](NO 3). Combining the results of solvent extraction and complexation study, the extraction mechanism was proposed. Furthermore, the stability constants (log β) and thermodynamic parameters (Δ H , Δ S , Δ G) for complexation of Eu3+ with Et- p -Tol-A-PzPy were also presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • TiNTA-CeNPs retained the cycling capability of Ce4+/Ce3+ in H 2 O 2 -containing PBS. • Preferable phosphate adsorption on Ti3+ in TiNTA-CeNPs preserved Ce3+ active sites. • Relationship between electronic structure and enzyme-like activity was established. • TiNTA-CeNP2 exhibited greater osteoprotective effect under oxidative stress. The core catalytic property of cerium oxide nanoparticles (CeNPs) has been proposed to be due to the redox cycling capability of Ce4+/Ce3+ oxidation state. Thus far there are few reports on controlling the cycling stability of Ce4+/Ce3+ couple in biological fluids which is the most important parameter in the application of CeNPs as a regenerative nano-antioxidant. In this study, vertically aligned titania nanotube array supported CeNPs (TiNTA-CeNPs), regardless of the pre-dominant Ce oxidation state, retained the cycling capability of Ce4+/Ce3+ in H 2 O 2 -containing phosphate-buffered saline (PBS) compared with Ti supported CeNPs. This was because preferable phosphate adsorption on surface Ti3+ in TiNTA-CeNPs preserved Ce3+ active sties. Accordingly, Ce3+-rich TiNTA-CeNP1 and Ce4+-rich TiNTA-CeNP2 in PBS exhibited more sustained superoxide dismutase and catalase mimetic response, respectively. A correlation between electronic band structures of Ce-Ti mixed oxides and redox potential of reactive oxygen species (ROS) aided in interpretation of enhanced redox cycling capability and enzyme-like activities. Less Fenton-active TiNTA-CeNP2 exhibited a greater ability to protect pre-osteoblasts against ROS-induced oxidative stress in vitro. To demonstrate in vivo osteoprotective effect of TiNTA-CeNP2, a rat model of oxidative stress-related osteoporosis was established. The results indicated that TiNTA-CeNP2 held great potential for ameliorating osteogenesis in oxidative stress-related bone diseases. [ABSTRACT FROM AUTHOR]

• The extraction of DGAs towards La3+, Pr3+, Nd3+, Eu3+, Gd3+, Y3+, Er3+ and Yb3+ was systematically investigated. • The extraction thermodynamic parameters (Δ H , Δ S and Δ G) were obtained. • The complexation of DGAs with Eu3+ was explored by means of FT-IR, 1H NMR, Luminescence spectroscopic titration and microcalorimetric titration. • The complexation stability constants and thermodynamic parameters of Eu3+ with DGAs were given. The extraction and complexation behaviors of four tetraalkyl diglycolamide (TRDGA, where R represents n -butyl, n -hexyl, n -octyl and 2-ethylhexyl) ligands with linear chain or branched chain structure were described with respect to La3+, Pr3+, Nd3+; Eu3+, Gd3+; Y3+, Er3+ and Yb3+ as the representatives of light, middle and heavy rare-earth group ions in HNO 3 solution. Effects of acidity, ligand concentration and temperature on the distribution ratio of these ions were examined. High acidity was good for the extraction. For same metal ion, the extractability of DGA ligands followed the order of T2EHDGA < THDGA < TODGA < TBDGA at the same acidity, which was also supported by nuclear magnetic resonance (NMR) analyses. Meanwhile, for different metal ions, their extracted efficiencies by the same DGA ligand increased in the sequence of lanthanide contraction. The average separation factors of adjacent lanthanides within light, middle and heavy rare-earth groups could attain about 2.4, 1.7 and 2.1, respectively. Slope analysis indicated that the formation of predominant 1:3 and 1:2 metal/ligand extracted species for linear chain and branched DGA, respectively. In methanol solution, 1:1, 1:2 and 1:3 Eu3+/DGA species were also observed using fluorescence spectroscopy titration. Fourier transform infrared spectroscopy (FT-IR) analyses suggested that the carbonyl oxygens compared with ether oxygen play a dominant role in coordination. Moreover, the stability constants (log β) and the thermodynamic parameters (Δ H , Δ S and Δ G) for the complexation of Eu3+ with DGAs were also presented. [ABSTRACT FROM AUTHOR]

The two DOTA-tetraamide ligands, DOTAM- n -butyl (1,4,7,10-tetrakis[(N - n -butyl; carbamoyl)methyl]-1,4,7,10-tetraazacyclododecane) and DOTAM-benzyl (1,4,7,10- tetrakis[(N -benzylcarbamoyl)methyl]-1,4,7,10-tetraazacyclododecane), were synthesized and characterized by MS, NMR and FTIR spectra. In acid solution, DOTAM- n -butyl was liable to be protonated. FTIR, 1H NMR, ESI-MS spectra and X-ray diffraction analyses revealed that the nitrogen atoms of cyclen ring combined two protons to form a cation with two positive charges. The protonated DOTAM- n -butyl had strong extraction ability and good selectivity for ReO 4 −. It was extracted by means of the substitution of one ReO 4 − for one NO 3 − in the 1:2 complex of DOTAM- n -butyl with HNO 3. The solvent extraction and X-ray crystallography demonstrated an anion-exchange extraction model. Meanwhile, X-ray crystal structure analyses of ligand complexes with HReO 4 or HNO 3 also indicated that ReO 4 − or NO 3 − ions were located in the gap between the upper and lower protonated ligands through multiple hydrogen bonds and electrostatic interactions. Image 1 • DOTA-tetraamide exhibited strong extraction ability and good selectivity for ReO 4 − separation in HNO 3 solution. • The single crystals for free ligand and its complexes with HNO 3 and HReO 4 were obtained for the first time. • An anion-exchange extraction model of ReO 4 − in HNO 3 solution by DOTA-tetraamide was determined. [ABSTRACT FROM AUTHOR]