In order to explore the abnormal disturbance of the space electric field caused by earthquakes using the electric field data of the ULF and VLF frequency bands of the electric field observed by the ZH-1 satellite, and taking the Mw7.7 earthquake in the Caribbean Sea in the southern sea area of Cuba on 29 January 2020 as an example, the signal-to-noise ratio of the NAA and NLK artificial source VLF transmitting stations in the Northern Hemisphere and the height of the lower ionosphere was calculated. The disturbance of the electric field in the ULF band was extracted using the S-G filtering method. The results indicate that: (1) The ionospheric anomaly caused by this earthquake appeared 20 days before the earthquake, and before the earthquake, there were significant anomalous changes in all parameters within the pregnant seismic zone. The signal-to-noise ratios of the NAA and NLK artificial source transmitter stations decreased by 30%, and the height of the low ionosphere decreased by 5–10 km, while there were anomalous perturbations in several orbits of the ULF electric field, and the magnitude of the perturbations exceeded three times the standard deviation. (2) The SNR of the artificial source transmitting stations before and after the earthquake was significantly reduced in the third period before the earthquake and recovered after the earthquake. (3) The low ionospheric height appears to be reduced before the earthquake and recovers after the earthquake. (4) The decrease in the S/N ratio occurred simultaneously with the decrease in ionospheric height 15 days–10 days before the earthquake. This provides a reference for extracting pre-earthquake ionospheric precursor anomalies.

In order to study the abnormal disturbance of the space ionosphere caused by strong earthquakes, the methods of SGF + WTA and EMD + ER are proposed and compared. The methods are applied to the 7.7 magnitude earthquake that occurred on the southern coast of Cuba on 29 January 2020 based on the electric field ultra-low frequency waveform data recorded by the ZH-1 electromagnetic satellite. Analyzing the electric field waveform data of the six orbits in and around the epicenter within five days before the earthquake and revisiting the orbit within two months, the significant information about the changes in the ionospheric electric field before the earthquake is obtained. The results demonstrate that: (1) in terms of time, large anomalies appeared before the earthquake on 16 January, and some orbital perturbations lasted until 2 February; (2) in terms of location, the disturbance changes are mainly concentrated over the central earthquake zone, and there are few conjugate zones; (3) in terms of amplitude, during the five days before the impending earthquake, most of the orbital disturbances exceeded the threshold of the background value while some of the orbital disturbances were less than the threshold; (4) in terms of morphology, the fluctuation that did not exceed the threshold appeared in the south of the earthquake area while a few appeared in the north. At the same time, the analysis method proposed in this paper is able to effectively extract the characteristics of electric field signal, clearly describe the abnormal signal change information before the earthquake, and provide a new method reference for the study of spatial electric field waveform data.

The theoretical development of Schumann Resonances has spanned more than a century as a form of global natural electromagnetic resonances. In recent years, with the development of electromagnetic detection technology and the improvement in digital processing capabilities, the connection between Schumann Resonances and natural phenomena, such as lightning, earthquakes, and Earth’s climate, has been experimentally and theoretically demonstrated. This article is a review of the relevant literature on Schumann Resonance observation experiments, theoretical research over the years, and a prospect based on space-based observations. We start with the theoretical background and the main content on Schumann Resonances. Then, observations and the identification of Schumann Resonance signals based on ground and satellite data are introduced. The research and related applications of Schumann Resonances signals are summarized in terms of lightning, earthquakes, and atmosphere. Finally, the paper presents a brief study of Schumann Resonances based on the China Seismo-Electromagnetic Satellite (CSES) and preliminary ideas about how to improve the identification and application of space-based Schumann Resonances signals.

Drug combinations have recently been studied intensively due to their critical role in cancer treatment. Computational prediction of drug synergy has become a popular alternative strategy to experimental methods for anticancer drug synergy predictions. In this paper, a deep learning model called DCE-DForest is proposed to predict the synergistic effect of drug combinations. To sufficiently extract drug information, the paper leverages BERT (Bidirectional Encoder Representations from Transformers) to encode the drug and the deep forest to model the nonlinear relationship between the drugs and cell lines. The experimental results on the synergy datasets demonstrate that the proposed method consistently shows superior performance over the other machine learning models.

To explore the correlation between earthquakes and the pre-earthquake ionospheric shallow frequency (ELF) electric field perturbations phenomenon, the paper investigated the pre-earthquake ionospheric perturbations phenomenon, and then the Spatio-temporal evolution characteristics of the electromagnetic field before and after the global Ms ≥6.0 strong earthquakes from 2019 to 2021 were statistically analyzed. In this paper, the power spectrum data of the ELF (19.5–250 Hz) band of ionospheric electric field observed by the China Seismo-Electromagnetic Satellite (CSES) electric field detector are preclinically processed by the C-value method. A stable background field observation model was constructed using the data from 75 to 45 days before the earthquake observed by the CSES in the range of 15° above the epicenter. Then, the amplitude of the spatial electric field disturbance over the epicenter relative to the background field is extracted. Finally, the superposition analysis method statistically analyzes the spatial and temporal evolution of the spatial electric field before and after the earthquake with different characteristics. The statistical results show that the anomalies first appear in the fourth period (15–19 days before the earthquake) and the third period (10–14 days before the earthquake) and then reach the most vital and most evident during the pro-earthquake period (4 days before the earthquake and the day of the earthquake); In terms of the intensity of the anomalies caused, the magnitude seven earthquakes are stronger than the magnitude 6.0–7.0 earthquakes, and marine earthquakes are stronger than land earthquakes; in terms of the ease of observing the anomalies, the magnitude 7.0 and above are more accessible to observe than the magnitude 6.0–7.0 earthquakes, and marine earthquakes are more accessible to observe than land earthquakes.

The ground-based artificial source electromagnetic signal transmitted to space will form a pair of intensity regions over the station and its conjugate point. In order to study the position and intensity of the strongest points in the two regions, the power-spectrum density (PSD) of the electric field on board the Zhangheng-1 satellite (CSES) was selected when it passed over the NWC artificial source transmitting station. The selected frequency is centered at 19.8 kHz with a bandwidth of 200 Hz. The strongest point is defined as the location with the maximum power spectral density of ±10° around the NWC station within 5 days, which is the revisiting period of the CSES. The results show that statistical characteristics of strongest points vary as day/night, local/conjugate point, longitude/latitude, and different components of electric field vectors. In terms of longitude deviation, it is mostly westward offset at night and on both sides in the day over the NWC but opposite at the conjugate point. In terms of latitude deviations, it is equator-ward at night and the same during the day with a smaller deviation. While over the conjugate point, it is northward offset in the day and both at night with a bigger offset. In terms of intensity, it is stable without obvious seasonal changes over the NWC and its conjugate point. The intensity of PSD is higher at night than during the day. For the PSD intensity of the three components, the descending order over the NWC is Ead, Eab, and Ecd at night and Ecd, Ead, and Eab in the day, and the opposite is true for over the conjugate point.