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The strip‐like bulge is a storm‐time conjugate ionospheric plasma density enhancement, constituted by the plasmaspheric H+/He+, that extends widely (over 150° in longitude) in the zonal dimension but occupies only 1°–5° in latitude. Based on in‐situ measurements of 11 low earth orbit satellites, this study statistically investigates the bulge structures of geomagnetic storms driven by 136 interplanetary coronal mass ejections during 2000–2021. The statistical results show that the strip‐like bulges are observed at the end of the storm main phase and can persist for more than 60 hr. The spatial and temporal coverage of the strip‐like bulge varies from storm to storm. However, the bulges do exhibit occurrence preferences: stronger storms (for the ICME‐driven) during solar minimum periods, the Asian‐Pacific sector (with eastward magnetic declination), and the nightside of the dawn‐dusk terminator. A quiet time density enhancement called mid‐latitude enhancement could be recognized as a precursor of the strip‐like bulge. The evolution features of the plasmapause height exhibit similarities with the strip‐like bulge, indicating a field‐aligned downward and cross‐L inward intrusion of the plasmaspheric ions. The local net ion drifts partly support this scenario with downward/inward being the most dominant but not unique pattern, the other diverse net ion drift configurations exist but their impact on the strip‐like bulges remains unclear. Plain Language Summary: A geomagnetic storm is a major disturbance of Earth's magnetic field when energy from the solar wind is effectively injected into the space environment surrounding Earth. During a storm, the ionosphere from 80 to 1,000 km is affected, and a sharp increase in ionospheric ion density with a narrow latitudinal range could be observed at low‐mid latitudes. The main ions constituting the sharp increase are H+/He+, which are the primary ions in the plasmasphere. We called this increase the "bulge." Toward a better understanding of the principal nature as well as the formation mechanisms of the structure, we extracted a number of samples snapshotted by many satellites to conduct a statistical investigation. It is found that the bulges prefer to appear in the Asian‐Pacific region, at 18:00‐06:00 LT, during strong storms, and under solar minimum conditions. Before their appearance, a smoother density peak structure is often observed, which could be recognized as the precursor. We suggested a substantial transfer of ions from higher to lower altitudes and the storm‐induced disturbance neutral wind, causing the smoother density peak structure to evolve into the bulge. Key Points: Occurrence of bulge has no strict limitation but shows some dependences on longitude, storm intensity, local time, and solar activityMidlatitude extra density peak could be recognized as a precursor of the strip‐like bulgeIon drift within the flux tube of the bulges is mainly in the field‐aligned downward/cross‐L inward pattern [ABSTRACT FROM AUTHOR]

Tumor microenvironment (TME) plays an important role in the tumor progression. Among TME components, cancer‐associated fibroblasts (CAFs) show multiple tumor‐promoting effects and can induce tumor immune evasion and drug‐resistance. Regulating CAFs can be a potential strategy to augment systemic anti‐tumor immunity. Here, the study observes that hydrogen treatment can alleviate intracellular reactive oxygen species of CAFs and reshape CAFs' tumor‐promoting and immune‐suppressive phenotypes. Accordingly, a controllable and TME‐responsive hydrogen therapy based on a CaCO3 nanoparticles‐coated magnesium system (Mg‐CaCO3) is developed. The hydrogen therapy by Mg‐CaCO3 can not only directly kill tumor cells, but also inhibit pro‐tumor and immune suppressive factors in CAFs, and thus augment immune activities of CD4+ T cells. As implanted in situ, Mg‐CaCO3 can significantly suppress tumor growth, turn the "cold" primary tumor into "hot", and stimulate systematic anti‐tumor immunity, which is confirmed by the bilateral tumor transplantation models of "cold tumor" (4T1 cells) and "hot tumor" (MC38 cells). This hydrogen therapy system reverses immune suppressive phenotypes of CAFs, thus providing a systematic anti‐tumor immune stimulating strategy by remodeling tumor stromal microenvironment. [ABSTRACT FROM AUTHOR]

The ionosphere exhibits complex variations due to the influences from above and below. To distinguish the source of ionospheric disturbances is important for understanding the variation process and the coupling mechanism among different regions. Using the ionospheric total electron content (TEC) derived from Global Navigation Satellite System observations, the ionospheric disturbances during the super typhoon Hato in 2017 that was accompanied by a weak geomagnetic storm are revisited, including the ionospheric deviation and traveling ionospheric disturbances (TIDs). It is found that the ionospheric TEC in the low‐latitude region of China experienced a significant enhancement (200% compared to the quiet geomagnetic day) on Hato landing day. This enhancement covers the northern and southern equatorial ionization anomaly (EIA) region from 80°E to 180°E. Considering the geomagnetic condition, the hmF2 and the O/N2 ratio in thermosphere, it is concluded that this enhancement is not related to the typhoon, but to the coinciding weak geomagnetic storm. Additionally, several medium‐scale TIDs are verified from differential TEC data in China low latitude region during Hato period. Most of them occur after sunset and their propagating direction is southwest that often occur in East‐Asian sector in summer months, which are not related to the typhoon. While a few TIDs with concentric wavefront (Concentric TIDs) are also observed on the day before Hato landfall that should be excited in the deep convective region of the typhoon. Because the ionosphere is affected by disturbances both from above and below, it should be careful to determine the source of the ionospheric disturbances. Plain Language Summary: The ionospheric conditions can be influenced by factors from both above (such as solar flares and geomagnetic storms) and below (including volcanoes, earthquakes, and severe weather disturbances). To distinguish these sources from ionospheric observations is important for understanding the ionospheric variability and is practically necessary for the ionospheric forecast. On the day of Typhoon Hato landfall (23 August 2017), the Total Electron Content (TEC) in the low‐latitude region of China experienced a great increase. It is noted that a weak geomagnetic storm also occurred on the landfall day. So, to determine the reasons of this enhancement becomes very interesting. In this study, we revisit ionospheric disturbances using dense Global Navigation Satellite System stations, ionosondes, space environment and meteorological data. Our results demonstrate that the primary source of this TEC enhancement is the weak geomagnetic storm rather than typhoon Hato. Additionally, we analyze several Traveling Ionospheric Disturbances that have different sources during the typhoon period, furtherly clarifying the impact of Hato on the ionosphere. Through this study, we emphasize the importance of the depth and comprehensiveness of relevant research in determining the sources of ionospheric disturbances. Key Points: Significant ionospheric total electron content increase over low latitude region of China on the day of Hato landfall is not related to typhoon but to the coinciding weak geomagnetic stormSeveral traveling ionospheric disturbances (TIDs) events are observed in the low latitude region of China during Hato period, but only the concentric TIDs occurred on 22 August 2017 is related to HatoBecause the ionosphere is affected by disturbances from above and below, it should be careful to determine the source of disturbances, especially those originating from below [ABSTRACT FROM AUTHOR]

Equatorial plasma bubbles (EPBs) occur frequently in low-latitude areas and have a non-negligible impact on navigation satellite signals. To systematically analyze the effects of a single EPB event on multi-frequency signals of GPS, Galileo, GLONASS, and BDS, all-sky airglow images over South China are jointly used to visually determine the EPB structure and depletion degree. The results reveal that scintillations, or GNSS signal fluctuations, are directly linked to EPBs and that the intensity of scintillation is positively correlated with the airglow depletion intensity. The center of the airglow depletion often corresponds to stronger GNSS scintillation, while the edge of the bubble, which is considered to have the largest density gradient, corresponds to relatively smaller scintillation instead. This work also systematically analyzes the responses of multi-constellation and multi-frequency signals to EPBs. The results show that the L2 and L5 frequencies are more susceptible than the L1 frequency is. For different constellations, Galileo's signal has the best tracking stability during an EPB event compared with GPS, GLONASS, and BDS. The results provide a reference for dual-frequency signal selection in precise positioning or TEC calculation, that is, L1C and L2L for GPS, L1C and L5Q for Galileo, L1P and L2C for GLONASS, and L1P and L5P for BDS. Notably, BDS-2 is significantly weaker than BDS-3. And inclined geosynchronous orbit (IGSO) satellites have abnormal data error rates, which should be related to the special signal path trajectory of the IGSO satellite. [ABSTRACT FROM AUTHOR]

This study investigates the vertical kilometre-scale fluctuations (KSFs) seen on the Mars Global Surveyor (MGS) radio-occultation (RO)-derived electron density profiles (EDPs) by wavelet spectrum analysis. A delicate five-peak signature is revealed: in the northern polar region near the dawn–dusk terminator, the amplitudes of the KSF peak at fixed altitudes with a constant separation of approximately 28 km. The feature could not be noticed on a single EDP; averaging with at least tens of continuously collected EDPs is needed, suggesting that the phenomenon is not instantaneous (time duration of each RO event is ∼7 min), but on a time-scale of days (observation time for tens of continuous RO events). Applying similar background criteria, Mars Atmosphere and Volatile EvolutioN (MAVEN) Radio Occultation Science Experiment derived EDPs could also occasionally capture similar multipeak features, indicating either that it is a natural ionospheric structure or that both MGS and MAVEN suffer the same artefact. The two indications are discussed, and a preliminary hypothesis is raised. A linear superposition with a 28 km standing wave might modulate the amplitude of KSF, and the 28 km standing wave might be associated with the ionospheric buoyancy waves disturbed by the upstream solar wind, while the plasma instabilities might trigger the KSF in the backgrounds of the draped magnetic field and day-to-night neutral winds. [ABSTRACT FROM AUTHOR]

The abundant observations and research established a detailed category of the terrestrial ionospheric irregularities, which significantly advanced our understanding of how the Earth system's complicated physical and chemical process generates the intermediate‐scale structures of the charged particles. Motivated by a future attempt at categorizing the Martian ionospheric irregularity, this study designs a method for naive classification of the plasma density depletion, enhancement, and oscillation based on the in situ measurements of the Martian ionosphere. The technique consists of several procedures: trend estimation, detrending and candidate extraction, and parameterization. The classification is achieved through a machine‐learning‐like process using some testing artificial density profiles. A preliminary credence test shows a good performance in separating the terrestrial low‐latitude Equatorial Plasma bubble (depletion) and mid‐latitude Median‐scale Traveling Ionospheric Disturbance (oscillation). Another detection experiment of the Martian plasma depletion events (collected by Basuvaraj et al. (2022a, https://doi.org/10.1029/2022je007302)) showed a recall rate (i.e., true positive) of 38% but with a high precision of 67.8%. Therefore, we believe the proposed method could convincingly extract different Martian ionospheric irregularities and help uncover the climatological characteristics in the future. Plain Language Summary: Ionospheric irregularities refer to the inhomogeneous distribution of the charged particles in the ionosphere, which would affect radio wave transmission and thus pose threats to tremendous human‐made assets deployed in terrestrial outer space and on other planets such as Mars. Unlike the terrestrial ionospheric irregularities, whose categories and physical mechanisms are well‐understood, the Martian counterparts are still in poor understanding. Previous studies have indicated the diversity, but the category has yet to be built. The large data set provided by the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission allows a more detailed investigation of the Martian ionospheric irregularities. Therefore, an automatic method to extract the ionospheric density enhancement, depletion, and oscillation would be a first step to figuring out the exact types of the Martian ionospheric irregularities, thus helping to extend our knowledge of how the finer ionospheric structures are formed backgrounded by the region crustal magnetic field other than the global dipole field. Key Points: A modified rolling‐barrel algorithm extracts the candidate irregularitiesClassification of the candidates into depletion, enhancement, and oscillation is achieved through a few parameterization processesInitial testing shows good performance on the Martian and terrestrial ionospheric irregularities [ABSTRACT FROM AUTHOR]

Cancer immunotherapy holds great promise but is generally limited by insufficient induction of anticancer immune responses. In this work, Microcystis aerugiosa (MA) is observed to act as an immune stimulator, which activates the cGAS‐STING and IRF‐signaling pathways of dendritic cells (DCs), induces immunostimulatory factors production, eventually resulting in the death of tumor cells by promoting cytotoxic CD8+ T cells infiltration. To further enhance the tumor immunogenicity, MA is engineered with polydopamine (PDA) and assembled in injectable Pluronic F127 hydrogels (denoted as MA@PDA‐F127). The introduction of PDA endows the MA@PDA‐F127 with photothermal therapy capability, which enhances the immunogenicity by in situ exposing damage‐associated molecular patterns and tumor antigens from dying tumor cells. Importantly, the surface‐rich reaction sites in thermosensitive MA@PDA‐F127 hydrogels capture antigens, facilitating long retention of antigens exposure and enhancing DCs maturation for advanced anti‐tumor immune response. Accordingly, in situ administration of MA@PDA‐F127 hydrogels in a single dose achieves efficient eradication of both primary and distant tumors in an orthotopic tumor metastasis model. Furthermore, this hydrogel can sensitize immune checkpoint inhibitor therapy and enhance T cell infiltration in a murine tumor model. Collectively, MA@PDA‐F127 hydrogel offers an effective anti‐tumor therapeutic by augmenting tumor immunogenicity and activating a systematic immune response. [ABSTRACT FROM AUTHOR]

The latitudinal location of the Equatorial Ionization Anomaly (EIA) crest has seasonal variation, and there are disagreements on the interpretation of such seasonal characteristic in previous studies. Some studies suggested that this seasonal characteristic is determined by the seasonal characteristic of the equatorial electric field. Others suggested that this seasonal characteristic is determined by the seasonal changes of the thermospheric wind. The current paper uses Total Electron Content (TEC) data and the Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) to analyze the seasonal variation of the northern EIA crest in the eastern Asian sector under low solar activity. Our results show that the monthly averaged latitudinal location of the northern EIA crest has a good linear relationship (r = 0.74) with the monthly averaged Equatorial Electrojet (EEJ) intensity, which is a commonly used proxy of the eastward electric field. However, TIEGCM simulations with and without F‐region wind indicate that such a relationship might be attributed to wind effects. Additionally, the linear relationship between the EEJ intensity and the northern‐southern EIA crest distance is not significant (r = 0.47) in the eastern Asian sector. Our results suggest that a good correspondence between the eastward electric field and the latitudinal location of the EIA crest is not assured annually, as the seasonally varying F‐region wind significantly influences EIA evolution. Key Points: Variations of the EIA crest latitude in the east Asian sector are analyzed with TEC data and TIEGCM simulationEEJ intensity and northern EIA crest latitude have a good linear relationship but might be attributed to F‐region meridional wind effectWind effect on the EIA evolution cannot be neglected on an annual timescale [ABSTRACT FROM AUTHOR]

Peak electron density data derived from GOLD measurements during 2018–2022 are used to analyze the magnitudes and correlations of ionospheric diurnal variability at low latitudes. The correlation distance describes the correlations between spatial locations and is defined in this paper as the angular separation at which the correlation coefficient decreases from 1 to 0.7. Variations in correlation distance with local time, season, magnetic latitude, solar activity, and geomagnetic activity are discussed in this study. The average value of the zonal correlation distance is approximately 8.55° and 3.56° for the meridional direction at low geomagnetic latitudes (magnetic latitudes <30°). The statistical results indicate that both zonal and meridional correlation distances vary little with local time premidnight, while they show pronounced seasonal and latitudinal variations. Both zonal and meridional correlation distances increase with increasing solar activity and decrease with enhancing geomagnetic activity. The EIA strength and gradient mainly modulate the distributions of correlation distances related to magnetic latitude, season, and solar flux level. An empirical model is constructed to describe the temporal and spatial variations in the correlation distance at low latitudes. The study of correlation distances would contribute to a better understanding of ionospheric variability and improvements in data assimilation. Plain Language Summary: The correlation distance is an important parameter in determining the background covariance matrix in data assimilations, which helps to transfer information from observations to the model‐driven background. The study of correlation distances can not only promote a better understanding of ionospheric variability but also improve ionospheric forecasts. More than 1,400 days of GOLD Nmax (peak electron density) data are applied for the statistical analysis of the correlation distance. In general, the correlation distance presents pronounced seasonal and latitudinal variations, varies little with local time premidnight, increases with increasing solar activity, and decreases with enhancing geomagnetic activity. The morphology of the EIA has a direct control on the correlation distance. The EIA strength and gradient mainly modulate the distributions of correlation distances related to magnetic latitude, season, and solar flux level. An empirical model is constructed, and it can effectively describe the temporal and spatial variations in the correlation distance at low latitudes. The results of correlation distances could further improve the accuracy of data assimilation. Key Points: EIA structures directly control the variation of correlation distancesHorizontal correlation distances increase with solar activity and vary with seasonAn empirical model is constructed to describe the variation in correlation distances with LT, mlat, season, solar and geomagnetic activities [ABSTRACT FROM AUTHOR]