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Absolute observation and relative record are two methods in geomagnetic station observation. The actual values of geomagnetic field elements can be obtained after the relative record data is corrected by baseline data. Fluxgate theodolite is one of the basic tools required to obtain baseline values and plays an important role in geomagnetic observations. At present, fluxgate theodolite used in stations requires manual operation, and human factors affect the observation data quality. Because absolute geomagnetic observation cannot be realized in remote areas or areas with harsh environments, some blank areas in the coverage of geomagnetic absolute observation exist. The second phase of the Chinese Meridian Project will carry out automatic geomagnetic absolute observation of magnetic declination and inclination for the first time in China's mainland, which will promote the innovation and development of geomagnetic absolute observation technology. The automatic fluxgate theodolite is a self-developed equipment from China for automatic observation of magnetic declination and inclination. It adopts non-magnetic materials and piezoelectric motors, effectively overcomes and eliminates the systematic errors by optimizing the design, improves the machining process, and compensates for the multi-parameter error algorithm, so as to ensure measurement accuracy. The equipment has been applied to long-term practical observation in stations such as Shexian Station in Hebei Province, Helong Station in Jilin Province, Qianling Station in Shanxi Province and Baijiatuan Station in Beijing. Compared with the observation results of artificial fluxgate theodolite in these stations, the results show that the main performance of the automatic fluxgate theodolite is the same as that of the artificial fluxgate theodolite. The equipment has also passed a precursor equipment standard test from the China Earthquake Administration, and its functions and performance meet the requirements of absolute geomagnetic observation for geomagnetic stations.

Accurate and timely crop distribution data are crucial for governments, in order to make related policies to ensure food security. However, agricultural ecosystems are spatially and temporally dynamic systems, which poses a great challenge for accurate crop mapping using fine spatial resolution (FSR) imagery. This research proposed a novel Tri-Dimensional Multi-head Self-Attention Network (TDMSANet) for accurate crop mapping from multitemporal fine-resolution remotely sensed images. Specifically, three sub-modules were designed to extract spectral, temporal, and spatial feature representations, respectively. All three sub-modules adopted a multi-head self-attention mechanism to assign higher weights to important features. In addition, the positional encoding was adopted by both temporal and spatial submodules to learn the sequence relationships between the features in a feature sequence. The proposed TDMSANet was evaluated on two sites utilizing FSR SAR (UAVSAR) and optical (Rapid Eye) images, respectively. The experimental results showed that TDMSANet consistently achieved significantly higher crop mapping accuracy compared to the benchmark models across both sites, with an average overall accuracy improvement of 1.40%, 3.35%, and 6.42% over CNN, Transformer, and LSTM, respectively. The ablation experiments further showed that the three sub-modules were all useful to the TDMSANet, and the Spatial Feature Extraction Module exerted larger impact than the remaining two sub-modules.

Abstract Purpose Interictal epileptiform discharges (IEDs) captured in electroencephalography (EEG) have a high diagnostic value for epileptic patients. Extending the recording time may increase the possibility of obtaining IEDs. The purpose of our research was to determine how long it took for various epileptic individuals to receive their first IEDs. Methods We retrospectively analyzed patients who were diagnosed with epilepsy and had no anti-seizure medications (ASMs) between September 2018 and March 2019 in the neurology department of the First Affiliated Hospital of Xi'an Jiaotong University. Each individual underwent a 24-h long-term video electroencephalographic monitoring (VEM) procedure. Clinical information including age, gender, age of seizure onset, frequency of seizures, the interval between last seizure and VEM, and results of neuroimaging were gathered. We also calculated the times from the start of the VEM to the first definite IEDs. Results A total of 241 patients were examined, including 191 with focal-onset epilepsy and 50 with generalized epilepsy. In individuals with focal-onset epilepsy, the median latency to the first IED was 63.0 min (IQR 19.0–299.0 min), as compared to 30.0 min (IQR 12.5–62.0 min) in patients with generalized epilepsy (p

Abstract Background Insulin resistance is a pivotal risk factor for cardiovascular diseases, and the triglyceride-glucose (TyG) index is a well-established surrogate of insulin resistance. This study aimed to investigate the prognostic value of the TyG index and its ability in therapy guidance in patients with three-vessel disease (TVD). Methods A total of 8862 patients with TVD with available baseline TyG index data were included in the study. The endpoint was major adverse cardiac events (MACE). All patients received coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or medical therapy (MT) alone reasonably. Results An elevated TyG index was defined as the TyG index greater than 9.51. During a median follow-up of 7.5 years, an elevated TyG index was significantly associated with an increased risk of MACE (adjusted hazard ratio 1.161, 95% confidence interval 1.026–1.314, p = 0.018). The elevated TyG index was shown to have a more pronounced predictive value for MACE in patients with diabetes, but failed to predict MACE among those without diabetes, whether they presented with stable angina pectoris (SAP) or acute coronary syndrome (ACS). Meanwhile, the association between an elevated TyG index and MACE was also found in patients with left main involvement. Notably, CABG conferred a significant survival advantage over PCI in patients with a normal TyG index, but was not observed to be superior to PCI in patients with an elevated TyG index unless the patients had both ACS and diabetes. In addition, the benefit was shown to be similar between MT and revascularisation among patients with SAP and an elevated TyG index. Conclusions The TyG index is a potential indicator for risk stratification and therapeutic decision-making in patients with TVD. Graphical Abstract

Objective: To illustrate the cerebral protective effect of scalp mechanical stimulation (SMS), similar to scalp acupuncture in basic mechanism, on cerebral edema in rats with cerebral hypoperfusion. Methods: First, we screened the strength of SMS by measuring skin temperature and blood perfusion using laser speckle contrast imaging. Next, we observed the cerebral protective effects on cerebral blood perfusion, cerebral edema, and pathological changes in rats with modified two-vessel carotid artery occlusion (2-VO). Furthermore, the apoptosis-related proteins (caspase-3, cleaved-caspase-3) and cerebral edema related proteins [antiglial fibrillary acidic protein (GFAP) and antiaquaporin-4 (AQP4)] were measured via immunohistochemistry and Western blot analysis. Additionally, the correlation between neural apoptosis and AQP4 protein levels was analyzed. Results: We found that 0.5 N was the best SMS intensity suitable for our study. Compared with the control group, 0.5, 1, and 2 N maintained the scalp temperature and improved scalp blood flow (all P

Abstract Objective Polymethylmethacrylate (PMMA) bone cement promotes the development of local thrombi. Our study found that a novel material, ES-PMMA bone cement, can reduce local thrombosis. We used a simple and reproducible animal model to confirm the reduction in local thrombosis and explored the associated molecular mechanism. Methods New Zealand rabbits, which were used to model thrombosis using extracorporeal carotid artery shunts, were divided into the following two groups, with 3 rabbits in each group: the PMMA bone cement group and the ES-PMMA bone cement group. Four hours after modelling, experimental samples, including thrombotic and vascular tissues, were collected. Thrombotic samples from the PMMA group and ES-PMMA group were subjected to lncRNA sequencing, and a lncRNA microarray was used to screen the differentially expressed lncRNAs. The expression of thrombomodulin in endothelial cells was quantified in vascular tissue samples. Differences in the lncRNA expression profiles between the thrombotic samples of the PMMA group and ES-PMMA group were assessed by base-to-base alignment in the intergenic regions of genomes. The lncRNA-miRNA-mRNA competitive endogenous RNA (ceRNA) network was established in light of ceRNA theory. Thrombosis was observed in the PMMA group and ES-PMMA group. Results The thrombotic weight was 0.00706 ± 0.00136 g/cm in the PMMA group and 0.00551 ± 0.00115 g/cm in the ES-PMMA group. Quantitative real-time polymerase chain reaction (RT–q-CR) and Western blotting revealed that the expression of CD40, which can regulate thrombosis in vascular endothelial cells, was significantly lower in the ES-PMMA group than in the PMMA group. High-throughput sequencing was used to identify 111 lncRNAs with lower expression in the ES-PMMA group than in the PMMA group. Through bioinformatics investigation, lncRNA MSTRG22719.16/ocu-miR-326-5p/CD40 binding sites were selected. Fluorescent in situ RNA hybridization (FISH) was performed to verify the lower expression of lncRNA MSTRG.22719.16 in vascular tissues from the ES-PMMA group. A dual-luciferase reporter gene assay was applied to verify that ocu-miR-326-5p binds the CD40 3ʹ-UTR and targets lncRNA MSTRG.22719.16. Conclusion Compared with PMMA bone cement, ES-PMMA bone cement can reduce thrombosis through the lncRNA MSTRG.22719.16/ocu-miR-326-5p/CD40 axis.

Abstract Background Polymethylmethacrylate (PMMA) bone cement loaded with enoxaparin sodium (PMMA@ES) has been increasingly highlighted to affect the bone repair of bone defects, but the molecular mechanisms remain unclear. We addressed this issue by identifying possible molecular mechanisms of PMMA@ES involved in femoral defect regeneration based on bioinformatics analysis and network pharmacology analysis. Methods The upregulated genes affecting the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) were selected through bioinformatics analysis, followed by intersection with the genes of ES-induced differentiation of BMSCs identified by network pharmacology analysis. PMMA@ES was constructed. Rat primary BMSCs were isolated and cultured in vitro in the proliferation medium (PM) and osteogenic medium (OM) to measure alkaline phosphatase (ALP) activity, mineralization of the extracellular matrix, and the expression of RUNX2 and OCN using gain- or loss-of-function experiments. A rat femoral bone defect model was constructed to detect the new bone formation in rats. Results ATF2 may be a key gene in differentiating BMSCs into osteoblasts. In vitro cell assays showed that PMMA@ES promoted the osteogenic differentiation of BMSCs by increasing ALP activity, extracellular matrix mineralization, and RUNX2 and OCN expression in PM and OM. In addition, ATF2 activated the transcription of miR-335-5p to target ERK1/2 and downregulate the expression of ERK1/2. PMMA@ES induced femoral defect regeneration and the repair of femoral defects in rats by regulating the ATF2/miR-335-5p/ERK1/2 axis. Conclusion The evidence provided by our study highlighted the ATF2-mediated mechanism of PMMA@ES in the facilitation of the osteogenic differentiation of BMSCs and femoral defect regeneration.

Unavoidable issues of micro-arc oxidation (MAO) coated Al alloys are the micro-defects and residual stress generation. Some scientists have reported the effects of micro-defects and residual stress on the fatigue performance of MAO coated samples. However, the influence of the residual stress sign in the MAO coating and substrate beneath the interface on the fatigue damage behavior of the substrate was controversial. Moreover, the coupling mechanism between micro-defects and residual stress on the fatigue performance of the MAO coated samples was nebulous. These present a challenge for the collaborative design of micro-defects and residual stress to optimize fatigue performance. Aiming at the issues, this paper summarized the influencing factors of MAO coatings on the fatigue performance of the substrate. From two aspects of microstructure characterization and stress analysis, the coupling mechanism between micro-defects and residual stress in fatigue failure was elucidated. And the mechanism of the micro-defects and residual stress on the fatigue damage behavior was developed. Finally, strategies to optimize the fatigue performance of MAO coated Al alloys were proposed. The results of this study have great guiding significance in regulating micropores, cracks, interface defects, and residual stress in MAO coatings in order to extend fatigue life.

Particle reinforced metal matrix composite (PRMMCs) has a complex mesoscopic structure, and the addition of particles can strengthen the metal matrix, which makes the deformation and failure behavior of PRMMCs under load very complicated. The finite element method can quantitatively describe the effect of PRMMCs microstructure parameters on the macroscopic properties of materials, but the key is to establish a representative volume element(RVE) model that can reflect the real mechanical properties of materials. This paper reports and discusses on the construction methods of the RVE model of PRMMCs from three aspects: the geometric modeling of PRMMCs microstructure, the construction of the matrix constitutive equation based on PRMMCs reinforcement mechanism and the interface module. In the end, Abaqus and some of its secondary development functions are introduced.

As one of the forth-generation nuclear energy system reactor types, lead fast reactor has good safety and economical properties due to the stable chemical properties of the coolant and the proliferation characteristics of the fuel, and modular nuclear power faster reactor designed for nuclear plant can further improve the economics of the reactor. In this article, the conceptual design of the lead-based modular power reactors with different power levels loaded with uranium alloy fuel is found to be found that when reactor core size increased to a certain level, the proliferation performance is too high due to the increase of the reactor core size under a specific core life such as 2000EFPD, so at the end of core life, the reactor core still has a large remaining reactivity. The proliferation advantage of the core cannot be fully released during the current core life time. Based on this phenomenon, in this article, we optimized the conceptual design of lead-based modular nuclear power reactor core loaded with uranium alloy fuel, and proposed to choose the appropriate rod to diameter ratio and effective density of fuel based on the power level and life time of the core. By adjusting the amount of uranium and 235U per unit volume, the proliferation performance of the core can be changed to match the power level and life time of the core. So the reactivity of core during the life period does not change, which not only reduce the difficulty of the reactivity control, but also make full use of the proliferation performance of the core. And at the same time, the reasonable rod to diameter ratio can provide safety and design margin for the analysis of thermal and hydraulic safety, and effectively improve the economy and safety of the core.

The deep integration of the digital economy and high-quality energy development is a vital breakthrough in promoting the digital transformation and upgrading of energy, and it is also a critical path to achieving green and low-carbon development. However, the degree of integration of the two has yet to be discovered. This article measures the coupling coordination degree of the digital economy and high-quality energy development using panel data from 30 provinces in China from 2013 to 2020, explores the spatiotemporal evolution characteristics of the coupling coordination degree, and further analyzes the driving factors of the coupling coordination degree. The results show that:(1) The coupling coordination degree shows an upward trend, but there are apparent gradient differences and spatial non-equilibrium features in the coupling coordination degree among provinces. (2) The coupling coordination degree shows a ''parabolic'' spatial trend of ''high east and low west'' in the east-west direction and an ''inverted U-shaped'' spatial trend in the north-south direction. (3) The center of gravity of the coupling coordination degree moves to the southwest, clustering in the northeast-southwest direction and showing a spreading trend in the southeast-northwest direction. (4) The coupling coordination degree has a significant positive spatial correlation, and the cold-hot spot gradually develops into a distribution pattern with the Yangtze River Delta in China as the agglomeration center. (5) Economic development, industrial structure, government behavior, environmental regulation, urbanization, technological innovation, and external openness significantly impact the coupling coordination degree. In addition, economic development and human capital have a positive spatial spillover effect on the coupling coordination degree. Urbanization level and technological innovation have a negative spatial spillover effect on the coupling coordination degree. Accordingly, to promote the coupling and interaction between the digital economy and high-quality energy development, the government should take effective measures in optimizing the industrial structure, scientifically promoting the urbanization process, and enhancing the scientific and technological innovation capacity.

Abstract Mechanical properties of red blood cells (RBCs) change during their senescence which supports numerous physiological or pathological processes in circulatory systems by providing crucial cellular mechanical environments of hemodynamics. However, quantitative studies on the aging and variations of RBC properties are largely lacking. Herein, we investigate morphological changes, softening or stiffening of single RBCs during aging using an in vitro mechanical fatigue model. Using a microfluidic system with microtubes, RBCs are repeatedly subjected to stretch and relaxation as they squeeze into and out of a sudden contraction region. Geometric parameters and mechanical properties of healthy human RBCs are characterized systematically upon each mechanical loading cycle. Our experimental results identify three typical shape transformations of RBCs during mechanical fatigue, which are all strongly associated with the loss of surface area. We constructed mathematical models for the evolution of surface area and membrane shear modulus of single RBCs during mechanical fatigue, and quantitatively developed an ensemble parameter to evaluate the aging status of RBCs. This study provides not only a novel in vitro fatigue model for investigating the mechanical behavior of RBCs, but also an index closely related to the age and inherent physical properties for a quantitative differentiation of individual RBCs.

Abstract New satellite remote sensing and machine learning techniques offer untapped possibilities to monitor global biodiversity with unprecedented speed and precision. These efficiencies promise to reveal novel ecological insights at spatial scales which are germane to the management of populations and entire ecosystems. Here, we present a robust transferable deep learning pipeline to automatically locate and count large herds of migratory ungulates (wildebeest and zebra) in the Serengeti-Mara ecosystem using fine-resolution (38-50 cm) satellite imagery. The results achieve accurate detection of nearly 500,000 individuals across thousands of square kilometers and multiple habitat types, with an overall F1-score of 84.75% (Precision: 87.85%, Recall: 81.86%). This research demonstrates the capability of satellite remote sensing and machine learning techniques to automatically and accurately count very large populations of terrestrial mammals across a highly heterogeneous landscape. We also discuss the potential for satellite-derived species detections to advance basic understanding of animal behavior and ecology.

Objective: To explore the mechanism and related active components of Yishen Daluo decoction (YSDLD) in treating multiple sclerosis (MS). Methods: Targets of YSDLD were collected through the TCMSP, Chemistry, and TCMID databases. The MS targets were collected through OMIM, DrugBank, Gencards, TTD, and Pharmgkb databases. We built “component–target” network diagrams and protein–protein interaction (PPI) diagrams and performed topological analysis. The targets were subjected to GO and KEGG enrichment analysis. Molecular docking verification was conducted on selected targets and molecules. Finally, in vitro experiments were conducted. BV2 cells were induced by lipopolysaccharide for model establishment. CCK8 experiment was conducted to explore the effect of YSDLD and RT-qPCR technology was used to explore the expression of key targets. Results: There were 184 active components in YSDLD and 898 targets of its action. There were 940 MS targets, and 215 targets were shared by YSDLD and MS. According to the “component–target” diagram, the top five key components included quercetin, kaempferol, beta-sitosterol, stigmasterol, and naringenin. IL-6, IL-1β, TNF-α, AKT1, and VEGFA were the important targets identified by PPI network topology analysis. A total of 564 functions were identified by GO enrichment analysis (P