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BaTiO3-xBi(Ni0.5Zr0.5)O3 powders were synthesized by traditional solid-state reaction method, and then BaTiO3-xBi(Ni0.5Zr0.5)O3 ceramics were prepared by spark plasma sintering. The crystal structure, micro-morphology, dielectric and impedance properties of the prepared ceramics were studied. The results show that BaTiO3-xBi(Ni0.5Zr0.5)O3 ceramics have perovskite structure and the crystal structure is pseudo-cubic phase, the grain size is about 0.64 μm, the density of the sample is 5.81 g/cm3, the maximum of the dielectric constant is 7149, and the phase transition temperature shifts to higher temperature with the increase of frequency. At 1 kHz, the slope of the fitting curve between ln(1/ε-1/εm) and ln(T-Tm) of BaTiO3-0.10Bi(Ni0.5Zr0.5)O3 ceramics is 1.61, and Δε/ε25 ℃≤±15% at -41-169 ℃, indicating that the sample has a good temperature stability. In addition, the impedance decreases with the increase of temperature and frequency; when the frequency is 100 Hz at 50 ℃, the resistance is 2.33×106 Ω and the ionic conductivity is 10-8 S/cm.

Objective: To explore the differential expression profiles of DNA methylation sites/regions and potential molecular mechanisms in the peripheral blood of coronary heart disease (CHD)-induced unstable angina pectoris patients with or without Qi deficiency and blood stasis syndrome, and to provide scientific evidence for the conbination of disease and syndrome. Methods: According to the pre-determined inclusion and exclusion criteria, the study subjects were enrolled and divided into two groups namely CHD-induced unstable angina group (G group) and healthy control group (J group) to conduct “disease” analysis, while G group was further divided into Qi deficiency and blood stasis syndrome group (case group) and non-Qi deficiency blood stasis syndrome group (control group) to perform “syndrome” analysis. The general data and clinical information of the study subjects were collected. The peripheral venous blood was extracted on an empty stomach, and the Illumina Infinium MethylationEPIC BeadChip (850K methylation chip) was used to detect the differential expression profiles of DNA methylation in each group, ChAMP software (V 2.14.0) was used for the differential methylation data analysis, with a threshold of the adjusted P value (adj.P.val) < 0.01. Gene Ontology (GO) and Kyoto Encyclopedia of Genomes (KEGG) were employed for the functional and pathway enrichment analyses of related mapped genes. Results: A total of 263 differentially methylated CpG positions (DMPs) were screened out between G and J groups, including 191 hypermethylated positions such as cg05845204 and cg08906898, and 72 hypomethylated positions such as cg26919182 and cg13149459. These positions were mainly mapped to 148 genes encompassing RNA binding motif protein 39 (RBM39), acetyl-CoA acyltransferase 2 (ACAA2), protein phosphatase 1 regulatory subunit 12B (PPP1R12B), and the dual-specificity tyrosine phosphorylation-regulated kinase 2 (DYRK2). GO functional enrichment analysis revealed that the genes of the DMPs were primarily enriched in protein localization to chromosomes, regulation of cell morphogenesis, negative regulation of calcium-mediated signals, etc. KEGG pathway analysis suggested that the genes were mainly enriched in fatty acid metabolism and endocytosis pathways. In addition, a total of 23 differential methylation regions (DMRs) were identified, with overlapping genes such as transmembrane protein 232 (TMEM232), ribosomal protein large P1 (RPLP1), peroxisomal biogenesis factor 10 (PEX10), and forkhead box N3 (FOXN3) recognized. It was found that GO functions were mainly enriched in the negative regulation of Ras protein signal transduction, small GTPase-mediated signal transduction, negative regulation, etc. A total of 1 703 differential methylation sites were screened out between case and control groups, including 444 increased methylation positions such as cg05573767 and 1 259 decreased methylationpositions such as cg19938535, and cg03893872. These positions were mapped to 1108 genes such as ribosomal protein S6 kinase A2 (RPS6KA2), leucine rich repeat containing 16A (LRRC16A), and hedgehog acyltransferase (HHAT). According to the GO functional enrichment analysis, the genes relating to the DMPs were mainly enriched in biological functions such as transmembrane receptor protein serine/threonine kinase signaling pathway and axonogenesis. The KEGG pathway enrichment analysis suggested the involvement of Rap1 signaling pathway, adenosine 5’-monophosphate-activated protein kinase (AMPK) signaling pathway, etc. A total of 21 DMRs were identified, including 22 overlapping genes such as mucin 4 (MUC4), three prime repair exonuclease 1 (TREX1), and LIM homeobox 6 (LHX6). GO analysis demonstrated that the genes primarily participated in molecular functions such as positive regulation of transmembrane transport, regulation of fatty acid metabolism, and copper ion binding. Conclusion: This study reveals the methylation patterns of DMPs and DMRs in patients with Qi deficiency and blood stasis syndrome caused by CHD-induced unstable angina pectoris. Potential epigenetic regulation of fatty acid metabolism, Rap1 signaling, and other molecular functions are involved in the development of CHD between the ''disease'' and ''syndrome''.

The surface of the synthetic diamond single crystal was etched by La2O3 at 820~980 ℃ with the nitrogen as the protective atmosphere to systematically study the effect of La2O3 etching on the properties of diamond single crystal. The surface morphologies of the etched diamond single crystal in the different crystal planes were observed by scanning electron microscope. The properties of the diamond single crystal before and after La2O3 etching were characterized by surface roughness, single particle compressive strength, impact toughness, and bending strength of Cu-based bonder diamond segments. The results show that, the La2O3 etching of the diamond in the {100} and {111} plane is anisotropic. When the etching temperature increases from 820 ℃ to 980 ℃, the surface roughness of {100} plane increases from 0.40 μm to 2.28 μm, while the surface roughness of {111} plane increases from 0.70 μm to 3.32 μm. The single particle compressive strength of the diamond decreases from 576 N (without etching) to the minimum of 530 N, and the impact toughness decreases from 92.94% to 89.21%. When the volume fraction of diamond is 5%, the bending strength of the etched diamond segment increases by 17.9%.

The work aims to explore the anisotropic etching of synthetic diamond single crystal by rare earth oxide. Under the protection of nitrogen, synthetic diamond single crystals were etched by Pr6O11 powder at 750-950℃. The surface morphology, phase composition and etching mechanism of different crystal surfaces of diamond single crystal after etching were characterized and analyzed by means of scanning electron microscopy, thermogravimetric analysis, X-ray diffraction and Raman spectroscopy, and the changes of diamond properties before and after etching were characterized by surface roughness, single particle compressive strength and impact toughness. The results show that the etching degree and morphology of {100} faces and {111} faces of diamond by Pr6O11 are different. When the temperature is 750℃, Pr6O11 etches slightly diamond crystals. The etching intensifies with the increase of etching temperature, moreover the etching degree of diamond {111} faces is more serious than that of {100} faces. The morphologies of the etching pits of diamond {111} faces change from triangular etching pits to layered triangular ones, and {100} faces change from slight quadrilateral to honeycomb-like etching pits. The maximum etching depth of {100} face increases from 1.12 μm to 12.54 μm, while the maximum etching depth of {111} face increases from 0.3 μm to 2.11 mm. The compressive strength of single diamond particle decreases from 576.25 N of unetched diamond to the smallest value of 530.06 N, and the impact toughness decreases from 92.94 J/cm2to 88.53 J/cm2. The etching mechanism of diamond single crystal by Pr6O11 is catalytic graphitization before 885℃, and the catalytic graphitization and oxidation after 885℃.

Perovskite Pb(Mg1/3Nb2/3)O3 (PMN) powder was synthesized by a hydrothermal route, and then, dense PMN ceramics with sub-micrometer grains were prepared by ultrahigh pressure sintering. The dielectric response and impedance spectroscopy was investigated in the temperature range of − 50-200 °C and the frequency range of 100 Hz-1 MHz. The sintered PMN ceramics had an average size of 0.4 μm and a relative density of greater than 98%, and it has a high dielectric constant (εrmax ~ 10,093) at 1 kHz and low dielectric losses (tanδ < 0.075). The phase transition temperature shifts to a high temperature with rising frequency and exhibits several broad dielectric peaks at various frequencies, demonstrating the typical relaxation characteristics of PMN ceramics. Additionally, when frequency increases, the impedance and resistance decrease, and the ionic conductivity is 9.99 × 10−9 S/cm at 25 °C when the frequency is at 100 Hz. [ABSTRACT FROM AUTHOR]

With global climate change and irrational human activities, regional water resource conflicts are becoming more and more pronounced. The availability of water resource in watersheds can be indicated by the water yield. Exploring the factors that influence the water yield is crucial in responding to climate change and protecting water resource. Previous research on the factors influencing the water yield has frequently adopted a macro-level perspective, which has failed to reflect the influencing mechanisms of changes at the local scale adequately. Therefore, this study proposes a novel framework for integrally evaluating the impacts of climate change and human activities on water yield services from both local and global perspectives. Taking Ganzhou City, the source of the Ganjiang River, as an example, the results show the following: (1) Ganzhou City had the largest water yield of 1307.29 mm in 2016, and the lowest was only 375.32 mm in 2011. The spatial distribution pattern was mainly affected by the surface environment, and the high-value water yield regions in the study area were predominantly located in urban areas with flat terrain. (2) At the local scale, regions where human activities contribute more than 80% accounted for 25% of the area. In comparison, the impact of climate change accounted for 0.95%. The contribution rate of human activities to the water yield in Ganzhou City was significantly greater than that of climate change. (3) At the global scale, the simulation results of four scenarios show that climate change contributed (>98%) to the water yield, which is significantly higher than human activities (<2%). This study puts forward pioneering views on the research of water yield driving forces and provides a valuable theoretical basis for water resource protection and ecological environment construction. [ABSTRACT FROM AUTHOR]

Solar irradiance received at the lunar surface is crucial for interpreting brightness temperatures detected by orbiters and for understanding the thermal, physical, and dielectric properties of the lunar regolith. We developed a real‐time effect solar irradiance (ESI) model that accounts for the influence of surface relief and terrain shading. This model was integrated with a standard thermal model to examine ESI fluctuations and their impacts on the diurnal physical temperature variations. To assess the effects of spatial resolution, we selected four locations with significant ESI disparities for simulation, then compared lunar surface temperatures at various spatial scales, ranging from 20 m to 25 km. Utilizing brightness temperature data obtained from the Chang'E‐2 (CE‐2) microwave radiometer (MRM), we integrated the shallow physical temperature profiles with the radiative transfer equation to simulate brightness temperatures and determine dielectric loss at different frequencies. In the Von Kármán crater, the received ESI exhibits a cyclical pattern of approximately 18 years and areas with rugged topography may exhibit larger ESI variations (∼7%). We found that the spatial resolution of ESI has a minimal effect on the physical and brightness temperatures at resolutions of 10 km or coarser. At the shallow layer, the average dielectric loss values are 0.0128–0.0170, 0.0083–0.0110, 0.0055–0.0073, and 0.0061–0.0081 for the CE‐2 frequencies of 3, 7.8, 19.35, and 37 GHz, respectively. The integration of real‐time ESI modeling, thermal dynamics, radiative transfer equations, and observational data enhances our comprehension of the physical temperature profile and thermal characteristics of shallow regolith. Plain Language Summary: The combination of solar irradiance and temperature data sets detected by orbiters can help to explain the temperature variation and thermophysical properties of shallow lunar surface. This study develops a real‐time effect solar irradiance (ESI) model that takes into account the influence of lunar topography and integrates it with a thermal model to simulate physical temperature variations within the Von Kármán crater. We compared lunar surface physical temperature profiles at spatial resolutions of 20, 240, 500 m, 1, 5, 10, 15, and 25 km, each exhibiting distinct ESI characteristics, to assess the impact of spatial resolution. We then simulated the temperature data in the four frequencies consistent with Chang'E‐2 (CE‐2) microwave radiometer and obtained the average ranges of dielectric loss. At 3, 7.8, 19.35, and 37 GHz, the average dielectric loss ranges were determined to be 0.0128–0.0170, 0.0083–0.0110, 0.0055–0.0073, and 0.0061–0.0081, respectively. These findings provide valuable insights for analyzing lunar surface temperature and observed brightness temperature, as well as for inverting physical and dielectric properties of the shallow regolith (e.g., dielectric loss). Key Points: Analyzing lunar shallow temperature variation with real‐time effect solar irradiance (ESI) model considering terrain influenceAssessing the real‐time ESI impact on physical and brightness temperature curves at diverse spatial resolutionsEstimating the dielectric loss of shallow regolith by coupling simulated brightness temperature data with observations [ABSTRACT FROM AUTHOR]

Rainfall-runoff simulation based on deep learning always costs plenty of time for training with large datasets. This may affect quick decision making in some flood emergency decision-making situations. To address this issue, this study proposes an incremental learning method to accelerate rainfall-runoff simulation with deep learning model. The method consists of two components, regular training and incremental operation. In regular training phase, the model is regularly trained using historical data. In the incremental operation phase, the method selects representative samples from historical data with distribution estimation metrics and time series similarity metrics, then updates the regularly trained model with the sampled data and recent data in case of emergency. The proposed method was tested using ten hydrological observation stations in the Yangtze River and Han River drainage basin, with three different modified Recurrent Neural Networks. The results show that the incremental learning method achieves a training efficiency acceleration of over 4 times, with only a little increase in percentage error and decrease in Nash-Sutcliffe efficiency coefficient. The results also illustrate the robustness of this method for different models in different places, as well as during continuous incremental scenarios. The findings indicate that the incremental learning method has great potential applications in rapid rainfall-runoff simulation for flood emergency decision-making. [ABSTRACT FROM AUTHOR]

Synthetic diamond crystallites were successfully etched by MnO2 powder. The effect of etching behavior on the surface morphology and properties of the treated diamond crystallites was investigated. Results showed that the etching intensity of both {100} and {111} planes increased as temperature increases, and the {111} plane was etched more significantly than the {100} plane under the same conditions. After etching, the morphology of etched pits on the {100} plane transformed from quadrilateral to octagonal, while those on the {111} plane were distinguished by triangular conical bulges. The compressive strength of a single diamond particle declines from 255 to 202 N, and the impact toughness decreases from 90.11% to 86.3%. More significantly, compared with raw diamond, the maximum flexural strength of the Cu-matrix bonding diamond block with etched diamonds increased from 394.2 to 464.9 MPa, an increase of 17.9%, and the cutting ratio of the diamond saw blades decreases from 17.5 to 9.67 g/m2. The ability to produce an anchoring connection between the etched diamond and the matrix accounts for the performance increase in diamond tools. The etching mechanism is a reaction between MnO2 and the C atom on the diamond surface. [ABSTRACT FROM AUTHOR]