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Precise and accurate determination of major components in alkali silicate glasses provides critical information concerning element distribution, petrogenesis and magmatic evolution. However, as one of the most important in situ microanalytical technologies, the application of electron probe microanalysis (EPMA) was limited by the time-dependent loss of X-ray intensity of alkali ions (especially Na) during electron beam bombardment on alkali silicate glasses. In this study, an optimized analytical method was developed using a JEOL JXA 8100 EPMA, aiming to get a long enough incubation duration suitable for accurate analysis of major element mass fractions. The optimal analytical conditions were determined as follows: 15 kV accelerating voltage, 2 nA beam current, 20 μm beam diameter, 40 s peak counting time, Na and K analyzed with top priority, time-saving mode with no additional detector movement and no peak search functioned. The availability of this low beam current density condition (6.37 × 10−3 nA μm−2) to 24 anhydrous reference glasses, with their compositions covering the entire spectrum from the ultramafic to highly siliceous range, was verified by the good agreement of the EPMA measured data with their GeoReM preferred values. Similarly, the methodology presented here is also suitable for analysis of hydrous glasses with H2O contents up to approximately 9 wt%, accompanied by no obvious Na loss found and no complicated mathematical corrections needed, and therefore can be used for the estimation of H2O contents in H2O-rich (>1 wt%) geological glasses by the difference method. Despite its analytical accuracy and precision (>0.5 wt%) not better than those of SIMS and FTIR, EPMA can be used as a substitute technique for H2O determination with its main advantages of excellent spatial resolution (down to 5–10 μm) and analytical convenience, especially for small melt inclusions or tiny experimental quench products, and the case with no appropriate calibration standards or no reported extinction coefficients available for those compositions of interest. In daily application, our optimized method is low cost and easy to implement and can achieve comparable precision and detection limits with acceptable efficiency (∼4–5 min/point for ten major elements) relative to routine analysis conditions. [ABSTRACT FROM AUTHOR]

Innovations in genomics have enabled the development of low‐cost, high‐resolution, single nucleotide polymorphism (SNP) genotyping arrays that accelerate breeding progress and support basic research in crop science. Here, we developed and validated the SoySNP618K array (618,888 SNPs) for the important crop soybean. The SNPs were selected from whole‐genome resequencing data containing 2,214 diverse soybean accessions; 29.34% of the SNPs mapped to genic regions representing 86.85% of the 56,044 annotated high‐confidence genes. Identity‐by‐state analyses of 318 soybeans revealed 17 redundant accessions, highlighting the potential of the SoySNP618K array in supporting gene bank management. The patterns of population stratification and genomic regions enriched through domestication were highly consistent with previous findings based on resequencing data, suggesting that the ascertainment bias in the SoySNP618K array was largely compensated for. Genome‐wide association mapping in combination with reported quantitative trait loci enabled fine‐mapping of genes known to influence flowering time, E2 and GmPRR3b, and of a new candidate gene, GmVIP5. Moreover, genomic prediction of flowering and maturity time in 502 recombinant inbred lines was highly accurate (>0.65). Thus, the SoySNP618K array is a valuable genomic tool that can be used to address many questions in applied breeding, germplasm management, and basic crop research. [ABSTRACT FROM AUTHOR]

Reinforcement learning as autonomous learning is greatly driving artificial intelligence (AI) development to practical applications. Having demonstrated the potential to significantly improve synchronously parallel learning, the parallel computing based asynchronous advantage actor-critic (A3C) opens a new door for reinforcement learning. Unfortunately, the acceleration's inuence on A3C robustness has been largely overlooked. In this paper, we perform the first robustness assessment of A3C based on parallel computing. By perceiving the policy's action, we construct a global matrix of action probability deviation and define two novel measures of skewness and sparseness to form an integral robustness measure. Based on such static assessment, we then develop a dynamic robustness assessing algorithm through situational whole-space state sampling of changing episodes. Extensive experiments with different combinations of agent number and learning rate are implemented on an A3C-based pathfinding application, demonstrating that our proposed robustness assessment can effectively measure the robustness of A3C, which can achieve an accuracy of 83.3%. [ABSTRACT FROM AUTHOR]

Quantum image encryption is a hot research topic in recent years. In this paper, a novel quantum image encryption algorithm based on quantum key image is presented, which has low complexity than other algorithms. The quantum key image is a special quantum image which is used to store the encryption keys. The encryption keys are generated by a cryptographic algorithm, and are prepared into the gray value of the quantum key image. Based on this quantum key image, the plain image does the XOR operations with it bit by bit. The circuit of the encryption algorthm is given, and the numerical simulations and theoretical analyses are done. The proposed encryption quantum image algorithm is efficiency, and it has large key space and lower computational complexity. [ABSTRACT FROM AUTHOR]

Objective To evaluate the changes of pain and sensory function in patients with idiopathic trigeminal neuralgia (ITN) treated by adriamycin interventional treatment, and to explore their correlation. Methods A total of 23 patients with ITN were treated by adriamycin interventional treatment guided via CT. Visual Analogue Scale (VAS) was used to evaluate the degree of pain before treatment and 1 d, 7 d, 1 month, 3 months, 6 months, 12 months after treatment. Quantitative Sensory Testing (QST) was used to measure cold sensation (CS), warm sensation (WS), cold pain (CP) and hot pain (HP) threshold value of chin at the affected side. Results Compared with before treatment, VAS scores decreased at 1 d, 7 d, 1 month, 3 months, 6 months and 12 months after treatment (P = 0.000, for all). One month, 3 months, 6 months and 12 months after treatment, CS (P = 0.003, 0.000, 0.000, 0.000) and CP (P = 0.022, 0.000, 0.000, 0.013) decreased, while WS (P = 0.004, 0.002, 0.000, 0.000) and HP (P = 0.004, 0.002, 0.000, 0.000) increased. Pearson correlation analysis showed VAS scores were positively correlated with CS (r = 0.703, P = 0.000) and CP (r = 0.679, P = 0.002), and negatively correlated with WS (r = -0.782, P = 0.000) and HP (r = -0.726, P = 0.001) after adriamycin interventional treatment. Conclusions QST was confirmed as noninvasive, simple and objective measurement. It could be used to quantificationally analyze the damage of sensory nervous function and could be a valuable index in evaluating the curative effect of trigeminal nerve destruction. [ABSTRACT FROM AUTHOR]

Cenozoic adakitic rocks in the Gangdese changed from barren continental melts to ore-forming slab melts at ~ 23 Ma. The distribution and chemical characteristics of the ore-forming adakites point to an association with the Ninetyeast Ridge. The subduction of the thick, rigid Ninetyeast Ridge changed the geometry and rheology of the eastern Tibetan Plateau lithosphere and asthenosphere, restrained the eastward escape of asthenospheric mantle as well as continental fragments, and promoted the uplift and building of the Tibetan Plateau, which consequently changed the tectonic and climatic regimes in eastern Asia. [ABSTRACT FROM AUTHOR]

A novel quantum image encryption and decryption algorithm based on iteration framework of frequency-spatial domain transforms is proposed. In this paper, the images are represented in the flexible representation for quantum images (FRQI). Previous quantum image encryption algorithms are realized by spatial domain transform to scramble the position information of original images and frequency domain transform to encode the color information of images. But there are some problems such as the periodicity of spatial domain transform, which will make it easy to recover the original images. Hence, we present the iterative framework of frequency-spatial domain transforms. Based on the iterative framework, the novel encryption algorithm uses Fibonacci transform and geometric transform for many times to scramble the position information of the original images and double random-phase encoding to encode the color information of the images. The encryption keys include the iterative time t of the Fibonacci transform, the iterative time l of the geometric transform, the geometric transform matrix G i which is n × n matrix, the classical binary sequences K ( $k_{0}k_{1}{\ldots } k_{2^{2n}-1}$ ) and $D(d_{0}d_{1}{\ldots } d_{2^{2n}-1}$ ). Here the key space of Fibonacci transform and geometric transform are both estimated to be 2. The key space of binary sequences is (2) × (2). Then the key space of the entire algorithm is about $2^{2{n^{2}}+52}$ . Since all quantum operations are invertible, the quantum image decryption algorithm is the inverse of the encryption algorithm. The results of numerical simulation and analysis indicate that the proposed algorithm has high security and high sensitivity. [ABSTRACT FROM AUTHOR]

Seamounts are an integral part of element recycling in global subduction zones. The published trace element and Pb-Sr-Nd isotope data for basaltic lavas from three key segments (Central Lau Spreading Ridge (CLSR), Eastern Lau Spreading Ridge (ELSR), and Valu Fa Ridge (VFR)) of the Lau back-arc basin were compiled to evaluate the contribution of Louisville seamount materials to their magma genesis. Two geochemical transitions, separating three provinces with distinct geochemical characteristics independent of ridge segmentation, were identified based on abrupt geochemical shifts. The origin of the geochemical transitions was determined to be the result of drastic compositional changes of subduction components added into the mantle source, rather than the transition from Indian to Pacific mid-ocean ridge basalt (MORB) mantle, or due to variable mantle fertilities. The most likely explanation for the drastic shifts in subduction input is the superimposition of Louisville materials on ‘normal’ subduction components consisting predominantly of aqueous fluids liberated from the down-going altered oceanic crust and minor pelagic sediment melts. Quantitative estimation reveals that Louisville materials contributed 0–74% and 21–83% of the Th budget, respectively, to CLSR and VFR lavas, but had no definite contribution to the lavas from the ELSR, which lies farthest away from the subducted Louisville seamount chain (LSC). The spatial association of the subducted LSC with the Louisville-affected segments suggests that the Louisville signature is regionally but not locally available in the Tonga subduction zone. Besides, the preferential melting of subducted old Cretaceous LSC crust instead of the old normal Pacific oceanic crust at similar depths implies that elevated temperature across the subduction interface or seamount erosion and rupture were required to trigger melting. A wider implication of this study, thus, is that seamount subduction may promote efficiency of element recycling in subduction zones. [ABSTRACT FROM AUTHOR]

The lithospheric mantle is of paramount importance in controlling the chemical composition of ocean island basalts (OIBs), influencing partial melting and magma evolution processes. To improve the understanding of these processes, the pressure–temperature conditions of mantle melting were investigated, and liquid lines of descent were modelled for OIBs on Pohnpei Island. The studied basaltic samples are alkalic, and can be classified as SiO2-undersaturated or SiO2-saturated series rocks, with the former having higher TiO2 and FeOT contents but with no distinct trace-element composition, suggesting melting of a compositionally homogenous mantle source at varying depths. Both series underwent sequential crystallization of olivine, clinopyroxene, Fe–Ti oxides, and minor plagioclase and alkali feldspar. Early magnetite crystallization resulted from initially high FeOT contents and oxygen fugacity, and late feldspar crystallization was due to initially low Al2O3 contents and alkali enrichment of the evolved magma. The Pohnpei lavas formed at estimated mantle-melting temperatures of 1486–1626 °C (average 1557 ± 43 °C, 1σ), and pressures of 2.9–5.1 GPa (average 3.8 ± 0.7 GPa), with the SiO2-undersaturated series forming at higher melting temperatures and pressures. Trace-element compositions further suggest that garnet rather than spinel was a residual phase in the mantle source during the melting process. Compared with the Hawaiian and Louisville seamount chains, Pohnpei Island underwent much lower degrees of mantle melting at greater depth, possibly due to a thicker lithosphere. [ABSTRACT FROM AUTHOR]