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The purpose of this work is to investigate the responses of multiple parameters to the Madoi earthquake preparation. A new method is employed to extract anomalies in a geomagnetic field. The results show that there were abnormal changes in the lithosphere, atmosphere, and ionosphere near the epicenter before the earthquake. Despite the differences in spatial and temporal resolutions, the increase in geomagnetic residuals in the lithosphere exhibits similar temporal characteristics to the enhancement of thermal infrared radiation in the atmosphere. Two high–value regions are present in the ground–based geomagnetic high residuals and the ionospheric disturbances. The northern one is around the epicenter of the Madoi earthquake. Near the southern one, an M6.4 Yangbi earthquake occurred four hours before the Madoi earthquake. In this study, we have observed almost all of the physical phenomena that can occur during the preparation of an earthquake, as predicted using the electrostatic channel model. It can be inferred that the electrostatic channel is a possible mechanism for coupling between the lithosphere, atmosphere, and ionosphere during the Madoi earthquake. [ABSTRACT FROM AUTHOR]

The method of bi-dimensional empirical mode decomposition (BEMD) and the combined methods of entropy weight–Technique for Order of Preference by Similarity to an Ideal Solution (TOPSIS) were used to decompose gravity–magnetic data and evaluate targets in the Luziyuan Pb–Zn–Fe polymetallic ore field and surrounding areas. Three meaningful bi-dimensional intrinsic mode function (BIMF) images were obtained by BEMD at different wavelengths, depicting different layers of geological architectures in the study area. The results are as follows. (1) The BIMF2 images depict the shallow local geological architecture and show positive gravity–magnetic anomalies of the skarn alteration and Pb–Zn–Fe mineralization distributed around concealed granites. (2) The BIMF3 images depict the medium-depth geological architecture, indicating that concealed granitic stocks, which are shallow extensions of a deeply concealed pluton, intruded along the NE-trending fault. (3) The BIMF4 images depict gravity–magnetic anomalies at greater depth, which likely reflect regional geological architectures, indicating the potential presence of a large, concealed intermediate-acid pluton in the negative anomaly zone. Three potential targets (A, B, and C) were delineated based on BEMD results of the original gravity–magnetic data. The entropy weight–TOPSIS evaluation results show that the ranking of the metallogenic potential of the delineated targets in the study area is B, A, and C, with relative proximity values of 0.4576, 0.3925, and 0.1499, respectively. The results of this study can be used to guide future exploration. [ABSTRACT FROM AUTHOR]

The aims of the present study were to use Langmuir Probe payload electron density data and Plasma Analyzer Package payload O+ density data from the Zhangheng-1 electromagnetic satellite to statistically analyze anomalies in electron and oxygen ion densities before strong earthquakes (Ms ≥ 6.0) in western China and its neighboring areas. The goal was to investigate the physical mechanisms underlying electron and oxygen ion generation by evaluating the correlations between such anomalies and the seismic activity before the 6.4-magnitude earthquake in Yangbi, Yunnan, China, on 21 May 2021. Nine (75%) of the twelve earthquakes that occurred during the study period and were not affected by magnetic storms were preceded by anomalous electron or oxygen ion densities of 1.1–4.5 × 1010/m3 and 2.8–6.0 × 1010/m3, respectively. The anomalies were generally observed within the two weeks preceding the earthquakes and were associated with most strike-slip and thrust earthquakes, which were mainly located on the southeastern and northwestern edges of the Tibetan Plateau—but not normal fault earthquakes. The anomalies were likely the result of acoustic-gravity waves generated by slow vibrations of the Earth's surface reaching the ionosphere, where they cause oscillations in ionospheric electron and ion densities. In addition, the association between ionospheric anomalies and strong earthquakes was confirmed by the observation of other atmospheric anomalies before the Yangbi earthquake. [ABSTRACT FROM AUTHOR]

Landslide is one of the most common geological hazards, which causes a large number of property damage and loss of life in China every year. This case study was a 330-kV transmission line project located in Longnan City, Gansu Province, China, which is known as an area prone to landslides. A hybrid model of fractal theory-information value-random forests algorithm (FT-IV-RF) was proposed to evaluate the landslide susceptibility. First, sixteen landslide conditioning factors and pre-existing landslide events were selected as the initial evaluation indexes of landslide susceptibility from four datasets (geology, topography, climate and environment, and landslide inventory). Second, Pearson coefficient and sensitivity analyses were conducted to extract ten landslide conditioning factors with small correlation and large contribution to landslide occurrence from sixteen factors. Third, the weight of each class for a given factor were determined by using a combination of fractal theory and information value algorithms, which was regarded as one of input parameters and used to select the training samples in the random forest model. Four, k-means clustering was performed to classify the landslide susceptibility indices, which were predicted using the random forest model, into five levels to produce the landslide susceptibility map of the study area. Furthermore, the proposed model of FT-IV-RF model was validated by comparing with results obtained using information value (IV), back-propagation neural network (BPNN), and fuzzy logic (FL) models. Good agreements on the susceptibility estimation were observed among four models, and the hybrid model had the largest area under the curve (AUC) value of 0.996, indicating a good performance of the proposed hybrid model. [ABSTRACT FROM AUTHOR]

The Bozhushan Ore Field, located at the western margin of the South China Block, is an important area for Ag-Pb-Zn-W polymetallic mineralization which may be associated with the Late Cretaceous granitic magmaism. In this paper, the singular value decomposition (SVD) was effectively applied to decompose gravity data at scale of 1: 50 000 within the Bozhushan Ore Field to extract deep ore-finding information. Two gravity anomaly images displaying different scales of the ore-controlling factors were obtained. (1) The low-pass filtered image may reflect the deeply buried geological structures, hidden intrusions and concealed ore bodies. The negative gravity anomaly may reflect the overall distribution of granite bodies in the Bozhushan Ore Field. One negative gravity anomaly area may correspond to the exposed part of the Baozhushan granitic intrusion and the other corresponds to the concealed part of the granitic intrusion. The granitic intrusions are the main ore-controlling factors in this ore district. (2) The band-pass filtered image depicts the shallow concealed geological structures and geological bodies within this study area. There are two obvious negative gravity anomalies, which may be created by the hidden granites at different depths at both northwestern and southeastern sides of the exposed granitic intrusion. Thus the two negative gravity anomalies are favorable prospecting areas for various type of polymetallic ore deposits at depth. The gravity anomalies extracted by using the SVD exactly reflect the distribution of the ore deposits, structures and intrusions, which will give new insights for further mineral exploration in the study area. [ABSTRACT FROM AUTHOR]

In response to wetland degradation in the middle and lower reaches of Yangtze River floodplain, wintering waterbirds move to artificial wetlands. Exploring changes in behavior associated with habitat shifts can further understanding of waterbird adaptation to anthropogenic landscapes with frequent disturbances. In winter 2017–2018, vigilance patterns in Bean Goose (Anser fabalis) and White-fronted Goose (Anser albifrons) were quantified in natural and artificial habitats in Shengjin Lake, one of the typical Yangtze-connected lakes in China. No significant difference in percentage time spent vigilant between species was found, but vigilance frequency of White-fronted Goose was higher than Bean Goose. Percent time spent vigilant and mean scan durations in both species were higher in rice fields (Bean Goose: 15.3% ± 2.0 SE and 12.3 sec ± 1.6 SE; White-fronted Goose: 15.7% ± 2.8 SE and 8.6 sec ± 1.4 SE) than in natural wetlands (Bean Goose: 7.8% ± 1.9 SE and 5.7 sec ± 1.1 SE; White-fronted Goose: 9.8% ± 1.2 SE and 6.4 sec ± 0.7 SE), while no significant difference was found in vigilance frequency between the two habitats. Flock size was a negative predictor of the three vigilance components. [ABSTRACT FROM AUTHOR]

Abstract: A bidimensional empirical mode decomposition (BEMD) program on a MATLAB platform was effectively used to handle gravity signals for the Tongshi gold field. This yielded a two-dimensional intrinsic mode function (IMF3) image that meticulously depicts the spatial distribution relationship between various gold deposits and the different geological units of the gold field. By combining the IMF3 image with geological features, the Tongshi gold field can be divided into three geological units. Unit I is made up of both Archean greenstone and Cambrian–Ordovician carbonate rocks and is defined as a concealed basement that exhibits weak negative and positive gravity anomalies. Unit II is defined as a Mesozoic volcanic sediment basin consisting of Jurassic and Cretaceous volcanic-sedimentary rocks, which developed on the concealed basement and exhibits an obvious negative gravity anomaly. Unit III, located on the concealed basement on the SW side of the Mesozoic volcanic-sedimentary basin, can be subdivided into subunits IIIa and IIIb. The former, with a negative circular gravity anomaly, indicates that the Tongshi complex consists of both Yanshan diorite-porphyrite and syenite-porphyry. Unit IIIb, with a positive ring gravity anomaly distributed around a negative circular gravity anomaly, indicates a possible contact metasomatic mineralization zone around the Tongshi complex. Almost all types of gold deposits are located within this contact metasomatic mineralization zone and thus the zone is a prospective area for gold deposits. [Copyright &y& Elsevier]

1. Reproductive biomass (RB) is a key component of plant life history. Because RB is allometric, it remains unclear whether the observed variations of RB in response to land use are driven only by a size dependency effect or if the partitioning of plant biomass may also shift independently of plant size. This question has not been addressed for all the main component species of a given plant community. 2. Here, we report the results of a 3-year experimental study conducted in Tibetan alpine grasslands. The above-ground vegetative biomass (VB) and the RB of 32 species were measured during 2 years in control, grazed and fertilized plots. We estimated the allometric slope and intercept for 301 VB–RB bivariates, using type II regression analyses in order to disentangle size-dependent and size-independent effects of treatment on RB. 3. Our results indicate significant changes in the VB–RB allometric slope for 26 out of 102 cases in grazed plots, and 16 out of 88 cases in fertilized plots. Moreover, in cases where slopes were not affected by treatment, a significant change in the allometric intercept was found in 50% of the models. For these cases, intercepts – which are indicative of the biomass invested in reproductive parts for a given VB – generally increased in grazed plots and decreased in fertilized plots. 4. Grazing and fertilization triggered a significant decreases or increases in the plant size for species, especially graminoids. However, we found no relationship between changes in allometric coefficients and magnitude of the biomass response. 5. At the interspecific level, the intercept, but not the slope, of the allometric VB–RB relationships was significantly affected by land use. Graminoids and forbs responded similarly to treatment. 6. Synthesis. We conclude that (i) size-dependent effects did not explain all the changes observed in RB following grazing and fertilization in alpine grasslands, and that (ii) changes in allometric intercept explained most of the size-independent variations both at the intra- and interspecific level. We discuss why size-independent changes in RB could be important for plant performance in changing environments. [ABSTRACT FROM AUTHOR]

The coseismic geothermal changes of ground temperature observed at observatories near the epicenter of the 2020 Jiashi Ms = 6.4 earthquake in China, provide a unique opportunity to study heat generation and conduction in rock. Here, evolutions of rock temperature at the Xikeer, Jiashizongchang, and Gedaliang observatories, which are located at epicentral distances of 1.4, 27.42, and 50 km respectively, were analyzed. Significant coseismic geothermal changes of 0.0432 °C were observed at the Xikeer observatory at the depth of 33.38 m, at which clear diurnal variations can be observed. Smaller changes of ~0.0001 °C were observed at the depths of 12.3 and 22.8 m at the Xikeer observatory and 22.3 m at the Jiashizongchang observatory. The stress transfer induced by the coseismic rupture induced a rise in local ground temperature, but the magnitude of the change was relatively small. The larger amplitude change at the Xikeer observatory was caused by fluid infiltration. We note that diurnal variation has been recorded at the Gedaliang observatory, but the coseismic response is no longer in existence. The temperature increases at the hypocentral area were higher than expected in the ground due to the coseismic stress transfer, but the change attenuated rapidly with distance. [ABSTRACT FROM AUTHOR]

The power network has a long transmission span and passes through wide areas with complex topography setting and various human engineering activities. They lead to frequent landslide hazards, which cause serious threats to the safe operation of the power transmission system. Thus, it is of great significance to carry out landslide susceptibility assessment for disaster prevention and mitigation of power network. We, therefore, undertake an extensive analysis and comparison study between different data-driven methods using a case study from China. Several susceptibility mapping results were generated by applying a multivariate statistical method (logistic regression (LR)) and a machine learning technique (random forest (RF)) separately with two different mapping-units and predictor sets of differing configurations. The models' accuracies, advantages and limitations are summarized and discussed using a range of evaluation criteria, including the confusion matrix, statistical indexes, and the estimation of the area under the receiver operating characteristic curve (AUROC). The outcome showed that machine learning method is well suitable for the landslide susceptibility assessment along transmission network over grid cell units, and the accuracy of susceptibility models is evolving rapidly from statistical-based models toward machine learning techniques. However, the multivariate statistical logistic regression methods perform better when computed over heterogeneous slope terrain units, probably because the number of units is significantly reduced. Besides, the high model predictive performances cannot guarantee a high plausibility and applicability of subsequent landslide susceptibility maps. The selection of mapping unit can produce greater differences on the generated susceptibility maps than that resulting from the selection of modeling methods. The study also provided a practical example for landslide susceptibility assessment along the power transmission network and its potential application in hazard early warning, prevention, and mitigation. [ABSTRACT FROM AUTHOR]

The significant decline in the number of newly discovered mineral deposits and the dramatical increase for the global demand for mineral resources in recent years have led exploration geologists to search for more efficient and innovative methods to explore recognized and concealed mineral resources. However, the multi-stages of metallogenesis have made the distribution of ore-forming elements exhibit complexly overlapped characteristics within geological units. We have been tasked with finding an innovative technology capable of recognizing ore footprints from the complexly overlapped phenomena created by the multi-stages of metallogenetic processes. In this study we establish a hybrid method by integrating Bi-dimensional empirical mode decomposition (BEMD) with Principal Component Analysis (PCA) to extract local and regional anomaly components of multi-element combination from stream sediment concentration data, which can be used for recognizing ore footprints. The proposed model is applied to spatial analysis of the mineralization in the giant Jiaodong Gold polymetallic Cluster Region (JGCR), Eastern China. The research results have shown as follows: (a) the two multi-element combinations of both Au–Ag–Cd and Be–La–Mo–Nb–Th–U–Y were established by PCA; (b) the local and regional anomaly components of the two multi-element combinations created by both magmatism and hydrothermal metallogenic processes were respectively recognized by the BEMD from the principal component scores of the two multi-element combination; and (c) the local anomaly components can identify Au–Ag–Cd and Be–La–Mo–Nb–Th–U–Y ore targets, and the regional anomaly components can recognize their high background zone favorable mineralization in the JGCR, Eastern China. Combined with the spatial distribution of both the local anomaly components and the granitic intrusions, it is inferred that the Au–Ag–Cd mineralization be related to the Linglong granitic intrusion and the Guojialing granodioritic intrusion, and the Be–La–Mo–Nb–Th–U–Y to the Guojialing granodioritic intrusion and the Weideshan monzonitic intrusions. The Guojialing granodioritic intrusion may be dual mineralization characteristics of both precious metals and critical metals. With the insights acquired from this study, the proposed hybrid method by integrating BEMD with PCA can serve as an effective tool in the exploration information system (EIS) to trace the footprints left behind by magma hydrothermal fluid flow for directing prospecting concealed ore bodies. The local anomaly components of Au–Ag–Cd combination from ore-forming events (a) and regional anomaly components of Au–Ag–Cd combination from magmatism (b), extracted by BEMD from PC4 scores which were established by PCA in the JGCR. [Display omitted] • The critical and precious element combinations were established using PCA in the JGCR. • The regional and the local anomaly components were extracted by BEMD. • The local anomaly components were used for mapping ore-prospecting targets. [ABSTRACT FROM AUTHOR]

The Laojunshan ore cluster region is situated at the north Song Chay dome, which is the junction of the Yangtze, the Cathaysia, and the Indo-China Blocks. The north Song Chay dome characterized by the Laojunshan metamorphic core complex is an important ore-forming region for W-Sn-Pb-Zn-In elements related to the Late Cretaceous granitic magmatism. In this paper, the Bi-dimensional empirical mode decomposition (BEMD) is applied to separate gravity components from the original gravity data, combined with the known geological and mineralized information, to explore the relationships between the gravity components and various ore-controlling factors at different depths. Four intrinsic mode functions (IMFs) and a residue are obtained. They may imply the spatial distribution of the geological bodies with featured gravity components at different depths. The results are shown as follows: (1) The low-pass filtering gravity component (BIMF4) implies the deeply buried geological units in the study region. The Cretaceous Laojunshan granitic complex and the Nanwenhe gneissic granite display negative gravity components and weak positive gravity components, respectively. The former is closely related to Sn-Zn-In mineralization, the latter is closely related to W polymetallic deposits. Therefore, the negative gravity components showing the Laojunshan granitic complex are the prospecting targets for deeply buried Sn-Zn-In deposits. The weak positive gravity components displaying the Nanwenhe gneissic granite are the prospecting targets for deeply buried W polymetallic deposits. (2) The band-pass filtering gravity component (BIMF3) implies the geological units at middle depth. The skarn-type Sn-W polymetallic deposits are observed in the transition zones from the positive to the negative gravity components, which coincide with the contact metasomatic zones between the Cretaceous granite and the Cambrian-Devonian carbonate rocks. Some small quartz vein W deposits occur within the Cretaceous Laojunshan granite with negative gravity components, and some layered W deposits occur in the Silurian gneissic granite with a weak positive gravity component. (3) High-pass filtering gravity component (BIMF2) implies geological units at the shallow crust, which shows that most of the deposits (occurrences) are located within the positive gravity component zones. These positive gravity component zones should be ore-finding targets for further prospecting for the undiscovered Sn and W polymetallic deposits. (4) The gravity components separated by BEMD coincide with the spatial distribution of the granites associated with various types of mineralization and alteration zones at different depths, which will give insights for further prospecting for concealed ore bodies in this study region. [Display omitted] • The mineralized characteristics of both the Sn-Zn-In and the W polymetallic deposits are recognized. • The gravity components implying ore-controlling factors at different depths are separated using BEMD. • The ore-finding targets of both the Sn-Zn-In and the W polymetallic deposits are identified using the gravity components. [ABSTRACT FROM AUTHOR]

Cepharanthine is a secondary metabolite isolated from Stephania. It has been reported that it has anti-conronaviruses activities including severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Here, we assemble three Stephania genomes (S. japonica, S. yunnanensis, and S. cepharantha), propose the cepharanthine biosynthetic pathway, and assess the antiviral potential of compounds involved in the pathway. Among the three genomes, S. japonica has a near telomere-to-telomere assembly with one remaining gap, and S. cepharantha and S. yunnanensis have chromosome-level assemblies. Following by biosynthetic gene mining and metabolomics analysis, we identify seven cepharanthine analogs that have broad-spectrum anti-coronavirus activities, including SARS-CoV-2, Guangxi pangolin-CoV (GX_P2V), swine acute diarrhoea syndrome coronavirus (SADS-CoV), and porcine epidemic diarrhea virus (PEDV). We also show that two other genera, Nelumbo and Thalictrum, can produce cepharanthine analogs, and thus have the potential for antiviral compound discovery. Results generated from this study could accelerate broad-spectrum anti-coronavirus drug discovery., (© 2024. The Author(s).)

Background There was little evidence about the role of objective sleep efficiency (SE) in the incidence of major cardiovascular disease (CVD) events. The purpose of this study was to investigate the correlation between objective SE and CVD based on polysomnography. Methods and Results A total of 3810 participants from the SHHS (Sleep Heart Health Study) were selected in the current study. CVD was assessed during an almost 11-year follow-up period. The primary composite cardiovascular outcome was major adverse cardiovascular events, defined as CVD mortality, congestive heart failure, myocardial infarction, and stroke. The secondary composite cardiovascular outcome was major adverse cardiovascular event plus revascularization. Objective measured SE, including SE and wake after sleep onset, was based on in-home polysomnography records. Cox regression analysis was used to explore the association between SE and CVD. After multivariate Cox regression analysis, poor SE (<80%) was significantly associated with primary (hazard ratio [HR], 1.338; 95% CI, 1.025-1.745; P =0.032) and secondary composite cardiovascular outcomes (HR, 1.250; 95% CI, 1.027-1.521; P =0.026); it was also found to be a predictor of CVD mortality (HR, 1.887; 95% CI, 1.224-2.909; P =0.004). Moreover, wake after sleep onset of fourth quartile (>78.0 minutes) was closely correlated with primary (HR, 1.436; 95% CI, 1.066-1.934; P =0.017), secondary composite cardiovascular outcomes (HR, 1.374; 95% CI, 1.103-1.712; P =0.005), and CVD mortality (HR, 2.240; 95% CI, 1.377-3.642; P =0.001). Conclusions Poor SE and long wake after sleep onset, objectively measured by polysomnography, were associated with the increased risk of incident CVD.

Since the development of single-hybrid maize breeding programs in the first half of the twentieth century 1 , maize yields have increased over sevenfold, and much of that increase can be attributed to tolerance of increased planting density 2-4 . To explore the genomic basis underlying the dramatic yield increase in maize, we conducted a comprehensive analysis of the genomic and phenotypic changes associated with modern maize breeding through chronological sampling of 350 elite inbred lines representing multiple eras of germplasm from both China and the United States. We document several convergent phenotypic changes in both countries. Using genome-wide association and selection scan methods, we identify 160 loci underlying adaptive agronomic phenotypes and more than 1,800 genomic regions representing the targets of selection during modern breeding. This work demonstrates the use of the breeding-era approach for identifying breeding signatures and lays the foundation for future genomics-enabled maize breeding.

Objective: To investigate whether coronary artery dominance is associated with the severity of coronary artery disease (CAD)., Design: Cross-sectional study., Setting: Single-centre., Participants: Between July 2015 and February 2017, 1654 patients who underwent coronary angiography (CAG) were recruited into this cross-sectional study., Measurement and Methods: According to coronary dominance, patients were classified into left dominance (LD), right dominance (RD) and codominance (CD) based on the CAG results. Multiple linear regression analysis was performed to test the association between severity of CAD and coronary dominance., Results: The total Gensini score was significantly higher in the RD group than in the left-CD group (42.3±33.6 vs 36.3±29.8; p=0.033). After adjusting for potential confounding factors, the results of multivariate linear regression showed that RD was associated with the severity of CAD (β=6.699, 95% CI 1.193 to 12.205, p=0.017)., Conclusions: The results suggest that right coronary dominance was associated with the severity of CAD., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: Recent reports suggest that Th17 immunity and bone marrow-derived CD34+ fibrocytes contribute to the pathogenesis of Graves' orbitopathy (GO). This study investigated interactions between Th17 cells and fibrocytes in GO inflammation in Chinese subjects., Methods: Th17 cells and fibrocytes were derived from blood samples from Chinese GO patients and healthy controls. Proportions and phenotypes of Th17 cells, regulatory T cells (Tregs), and fibrocytes were examined by flow cytometry. Exogenous IL-17A was used to study inflammatory activity of fibrocytes from GO patients and control subjects. Coculture, quantitative RT-PCR, Luminex, and transwell assays were performed to investigate the relationship between Th17 cells and fibrocytes., Results: CC-chemokine receptor 6 (CCR6+) Th17 cells were increased in both active (P < 0.001) and inactive (P < 0.05) GO patients, compared with healthy controls. There was a positive correlation between number of CCR6+ Th17 cells and GO clinical activity score (P < 0.0001, r = 0.8176). Further, CD34+ fibrocytes were increased in GO patients, with increased expression of IL-17RA (P < 0.05), CD80 (P < 0.05), and CD86 (P < 0.05). A decreased population of effector Treg cells (P < 0.01) and increased CTLA-4 expression on naïve Treg cells (P < 0.05) were observed in GO patients. IL-17A stimulated cytokine production in fibrocytes; GO fibrocytes exhibited more robust production than normal fibrocytes. Autologous Th17 cells promoted inflammatory and antigen-presenting functions of GO fibrocytes; conversely, fibrocytes enhanced Th17 cell-function and recruited Th17 cells in a macrophage inflammatory protein 3 (MIP-3)/CCR6-dependent manner., Conclusions: The crosstalk between CCR6+ Th17 cells and fibrocytes plays a role in the pathogenesis of GO. Suppressing these interactions may be a candidate molecular target for therapeutic approaches of GO.