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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]

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]

Immunotherapy is a revolutionary achievement in cancer treatment. However, inadequate immune cells infiltration in tumor microenvironment (TME) always leads to treatment failure. Moreover, hypoxic TME hampers normal functions of immune cells. Here, it is found that hypoxia suppresses the STING signaling and immune cells activation in the work. Remodeling tumor immune microenvironment and relieving hypoxia are thus essential for enhancing immunotherapy efficiency. Herein, a spirulina platensis (SP)‐based magnetic biohybrid system is constructed as an oxygen factory and loaded with stimulator of interferon genes (STING) agonist ADU‐S100 (ADU@Fe‐SP) for tumor immunotherapy. Magnet‐guided biohybrid SP can actively target tumor tissues and produce oxygen in situ through photosynthesis, which reverses the hypoxic TME and facilitates the function of immune cells. Besides, the targeted delivery of ADU‐S100 can activate the STING/TBK1/IRF3 signaling and boost cytokines production in tumor and innate immune cells. The ADU@Fe‐SP system thus induces efficient immune cells infiltration in TME, which efficiently inhibits tumor progression and significantly enhances anti‐PD‐1 therapy efficiency in SCC VII‐bearing tumor xenograft. ADU@Fe‐SP exerts antitumor effect in a STING‐dependent manner by in vivo STING‐knockout mice model. The efficiency of this immunotherapy strategy is also demonstrated in patient‐derived xenograft model originating from oral cancer, showing great clinical potential. [ABSTRACT FROM AUTHOR]

Gravity waves (GWs) are ubiquitous and important dynamical processes in planetary atmospheres. But their properties and impact on the lower atmosphere remain unclear for most of planets due to the lack of data. The recent in situ observation from Huygens reveals GW activity in Titan's lower stratosphere. This paper investigates the upward propagation of GWs from Titan's lower atmosphere and their thermal effects using a full‐wave model. We reproduce the observed temperature perturbations with a superposition of three GW solutions with λx = 50 km and λz = 5.3, 8.9, and 28 km, with the longer wavelength one overlooked in previous studies. The simulation suggests that the propagation of GWs in Titan's lower atmosphere is almost nondissipative and thus has no wave‐induced thermal effect on the stratosphere, which is very different from the planetary thermosphere. The temperature minimum at the tropopause leads to a rapid local GW growth, which may be the primary reason for the significant GW signals above 60 km. We also find that the zonal wind may filter out the majority of GWs except for those traveling perpendicular to the wind direction, which can propagate upward to above 100 km, as observed by the Huygens probe. Plain Language Summary: Gravity waves are wave‐like air motions in the atmosphere of various planets. However, due to the lack of observations, their detailed nature and impact on the lower atmosphere are unclear for most planets, including Titan, a moon of Saturn. Fortunately, recent observations from the Huygens spacecraft obtained the temperature profile of Titan's lower atmosphere, enabling the study of gravity wave (GW) activity there. This paper aims to use a model to simulate and study the observed GWs on Titan. We reproduce the observed temperature wave structure with three kinds of GWs of different spatial scales. We found that when GWs travel in the lower atmosphere of Titan, they are not weakened by the air as that occurs in the upper atmosphere. As a result, there is also no heating effect from the waves in the lower atmosphere. Instead, a layer of cool air at around 60 km altitude may lead to a rapid growth of GWs, which may be the main reason for much larger GW signals above 60 km than below. We also found that atmospheric wind can stop most of the GWs from traveling upward into the higher atmosphere of Titan. Key Points: The temperature fluctuations observed by the Huygens probe between 10 and 140 km are well reproduced by our full‐wave modelThe propagation of gravity waves (GWs) in Titan's lower stratosphere is almost nondissipative and has limited wave‐induced thermal effectThe rapid GW growth at the tropopause is caused by the thermal structure rather than the wind effect [ABSTRACT FROM AUTHOR]

We revisited a typical interplanetary (IP) shock event on 7 November 2004, with high time resolution (1 s) total electron content (TEC) observations. The IP shock impinged on the dayside magnetopause at ∼18:27 UT, and launched a pulse into the magnetosphere. Using the multi‐spacecraft timing method, the pulse was estimated to propagate at an angular velocity of ∼0.1 MLT/s. While the in situ spacecraft observations only provided a first‐order estimation of the propagation speed, a more precise monitoring of the propagating pulse was achieved by the densely distributed network of the Global Navigation Satellite System (GNSS). Following the shock arrival, GNSS receivers throughout the equatorial region recorded the associated TEC impulses. The signatures were sequentially observed from the sub‐solar to the nightside via both flanks, which in turn demonstrated the concrete propagation pattern of the pulse. In addition to a consistent angular velocity, a ∼40 s difference was systematically found between the TEC measurements and the in situ spacecraft observations, revealing the timescale of the shock‐induced magnetospheric‐ionospheric coupling. Key Points: Global Positioning System total electron content (TEC) impulses associated with the interplanetary shock impingement were systematically observed in the equatorial regionThe TEC observations showed an azimuthal propagation velocity of ∼0.1 MLT/s and a time delay of ∼40 s between the spacecraft observationsThe TEC technique achieved a monitoring of the shock‐induced pulse and revealed the timescale for the pulse to couple to the ionosphere [ABSTRACT FROM AUTHOR]

Gravity waves (GWs) are significant dynamical processes in planetary atmospheres due to their efficient transport of momentum and energy from the lower to the upper atmosphere. Recent observations from in‐situ measurements by spacecraft like Mars Atmosphere and Volatile Evolution (MAVEN) also reveal ubiquitous GW activity in the Martian thermosphere. As a critical parameter for characterizing GWs, the wavelength spectrum has been studied for years. However, most of the current observations for the Martian thermosphere can only determine the apparent GW wavelength because they usually take one‐dimensional measurements within a typical GW period. In this work, we adopt a full‐wave GW model to statistically investigate the upward propagation of the topographic‐generated GWs and how their wavelength spectrum apparently looks in the thermosphere when observed by a spacecraft like MAVEN. We find that the wind significantly modifies the vertical wavelengths of GWs in the Martian atmosphere. Considering the GWs generated from topographic sources, we calculate their wavelength distribution in the thermosphere, with a most probable apparent vertical wavelength of around 14 km, consisting with the MAVEN observation. However, our theoretical wavelength spectrum is mainly concentrated in the low wavelength part (10–20 km), while the observed result contains a long‐tailed component in the long wavelength part. The mismatch between our model and observations indicates that at least 72% of the observed GWs in the thermosphere are not generated from topographic sources. Plain Language Summary: Gravity waves are a common and important fluctuation phenomenon in the atmosphere of a planet like Earth and Mars. They can transfer energy from the lower atmosphere to the upper atmosphere. Recent observations of the Martian atmosphere by many spacecrafts have also seen this fluctuating activity in the Martian upper atmosphere. The wavelength distribution, that is, a feature representing the wave pattern's spatial scale and traveling speed, is very important for studying the characteristics of gravity waves. But most current observations of the Martian upper atmosphere have no way to determine the actual wavelength distribution effectively. In this work, we employ a gravity wave model to study the propagation of gravity waves generated from the topography and their wavelength distribution in the Martian upper atmosphere. We found that atmospheric winds can significantly alter the vertical wavelength of gravity waves. Our results indicate that these gravity waves are most likely to be observed in the upper atmosphere at a wavelength of about 14 km. However, our theoretically calculated wavelength distribution also partly differs from the observations. These differences suggest that at least 72 percent of the gravity waves observed in the upper atmosphere are not topographically generated. Key Points: We use a full wave model to simulate the upward propagation of topographic gravity waves to the Martian thermosphereThe apparent vertical wavelength spectrum of the topographic gravity waves in the Martian thermosphere peaks at around 14 kmAt least 72% of the observed gravity waves in the thermosphere are not generated from topographic sources according to our theoretical analysis [ABSTRACT FROM AUTHOR]

The ionosphere exhibits enhanced semidiurnal lunitidal (M2) perturbations during sudden stratospheric warming (SSW) events, of which the manifestation and mechanism are not well documented and understood. This paper studies the latitudinal and inter‐hemispheric variations of the ionospheric M2 perturbations during the 2021 major Arctic SSW with total electron content (TEC) data in the American, Asian‐Australian, and African‐European sectors. Results show that the M2 perturbations in the three sectors all enhanced during the SSW, with the strongest M2 perturbations in the Northern and Southern Hemispheres at about 10°∼15°N and 25°∼30°S geomagnetic latitudes, respectively. Also, clear M2 perturbations in the three sectors all extended to middle latitudes during the SSW only in the Southern Hemisphere. Comparatively, the inter‐hemispheric asymmetry of the magnitude of the M2 perturbations during the SSW was more complex. The inter‐hemispheric asymmetry of the crest locations of the low‐latitude M2 perturbations in the three sectors during the SSW was probably due to the F‐region meridional wind effect on the diffusion process of the low‐latitude plasma fountain. Meanwhile, the longitudinal differences were also obvious. The TEC M2 amplitude in the American sector was obviously larger than those in the Asian‐Australian and African‐European sectors during the SSW. The M2 characteristics in the southern middle latitude in the American sector were significantly different from those in the other two sectors during the SSW, which may be related to the differences of the combined effects of the local wind and geomagnetic configuration. In addition, a moderate geomagnetic activity occurred during the 2021 SSW, which brings difficulties to the analysis of the SSW‐related TEC variation. Key Points: The latitudinal differences of the ionospheric semidiurnal lunitidal (M2) perturbations during the 2021 sudden stratospheric warming were studied with total electron contentThe low‐latitude M2 perturbations exhibited similar latitudinal and inter‐hemispheric variations in the American, Asian and African sectorsThe M2 perturbation in the southern middle latitude was obviously different in the American from those in the Asian and African sectors [ABSTRACT FROM AUTHOR]

During the geomagnetic storm on 3–6 November 2021, the in‐situ plasma density and the gridded total electron content (TEC) maps registered a persistent presence of the strip‐like bulges (electron density enhancement, also known as the shoulders in previous literatures) at lower‐middle latitudes. The observed strip‐like bulge resided in the Pacific‐America‐Atlantic sector and lasted from 07:00 UT on 4 November to 20:00 UT on 6 November. For the first time, the temporal evolution of the 2‐D strip‐like bulge was recorded by gridded TEC maps, though observations were limited over the North American continents. The TEC maps showed a continuous shrinking of the nightside midlatitude plasma band structure right before the presence of the narrow strip‐like bulge. Simultaneous measurements from the Ionospheric Connection Explorer satellite (ICON) revealed an equatorward turning of the field‐aligned ion transportation driven by the disturbance equatorward neutral winds. However, the enhanced fountain effect at low latitudes was not observed during the entire formation phase of the strip‐like bulge. We propose that the storm‐induced enhanced equatorward thermospheric neutral winds push the plasma equatorward along the field lines, and the plasma band structure was developed into the strip‐like bulge. In addition, the ion composition of both the plasma band structure and the strip‐like bulges are dominated by H+, and the maintenance of the strip‐like bulge could be due to the compensation of the downward plasmaspheric content flux. Key Points: The temporal evolution of the 2‐D strip‐like bulge is recorded on gridded total electron content (TEC) mapsThe strip‐like bulge is a consequence of the narrowing midlatitude band structure driven by the disturbance neutral windThe enhanced equatorial fountain effect is not involved during the formation of the strip‐like bulge [ABSTRACT FROM AUTHOR]

Martian global dust storms have significant influences on its atmosphere and ionosphere. In this research, the behavior of O2+ ${\mathrm{O}}_{2}^{+}$, CO2+ ${\mathrm{C}\mathrm{O}}_{2}^{+}$, and O+ density profiles during the 2018 global dust storm is studied based on the observations of Neutral Gas and Ion Mass Spectrometer (NGIMS) onboard Mars Atmosphere and Volatile Evolution. The observations show increased CO2+ ${\mathrm{C}\mathrm{O}}_{2}^{+}$ density, decreased O+ density, and relatively stable O2+ ${\mathrm{O}}_{2}^{+}$ density at 170–500 km during the dust storm. Using a photochemical model, we reproduced the behavior of O2+ ${\mathrm{O}}_{2}^{+}$, CO2+ ${\mathrm{C}\mathrm{O}}_{2}^{+}$, and O+ density at 170–200 km during the dust storm based on the behaviors of NGIMS observed neutral density profiles. The behaviors of those neutral and ion density profiles should be the combined effects of the variations of latitude, longitude, season, local time, Solar Zenith Angle (SZA), and the activity of the global dust storm. Two different methods, one based on the Mars Climate Database and another based on a parametric model, are used to remove the effects of latitude, longitude, season, local time, and SZA variations on the neutral atmosphere and ionosphere. Both methods indicate that O2+ ${\mathrm{O}}_{2}^{+}$ density at 170–200 km should increase, rather than stay unchanged under the 2018 global dust storm‐specified effect. Plain Language Summary: The global dust storms have significant influences on the Martian atmosphere and ionosphere. Understanding the behavior of the Martian atmosphere and ionosphere during global dust storms is very important for landing and communicating on Mars. With the help of the Neutral Gas and Ion Mass Spectrometer onboard the Mars Atmosphere and Volatile Evolution spacecraft, we studied the behavior of different ion density profiles in the Martian upper ionosphere (above 160 km) during the 2018 Martian global dust storm. In this way, the expectation of the previous modeling research about the behavior of different ion density profiles at 170–400 km during the global dust storm is confirmed for the first time by observational results. The behavior of ion density profiles at 170–200 km during the dust storm is further reproduced based on the behavior of neutral density profiles, revealing that the ion density profiles below 200 km during dust storms follow the photochemical theory. With the help of two different models, the dust storm‐specified effects on the neutral and ion density profiles at 170–200 km are derived. This combination of observations and simulations could provide a more comprehensive understanding of the behavior of the Martian upper ionosphere and the coupling between the Martian upper ionosphere and neutral upper atmosphere during global dust storms. Key Points: The behavior of the Martian upper ionospheric ion density profiles during the 2018 global dust storm is investigatedAn increased density of CO2+ ${\mathrm{C}\mathrm{O}}_{2}^{+}$, decreased density of O+, and stable density of O2+ ${\mathrm{O}}_{2}^{+}$ at 170–500 km were found during the dust stormThe dust storm‐specific effects on the ion density profiles at 170–200 km are derived [ABSTRACT FROM AUTHOR]

The Huygens Atmospheric Structure Instrument (HASI) detected wavelike temperature fluctuations from 500 to 1,000 km on Titan. However, these fluctuation structures have not been satisfactorily reproduced by any theoretical model to date. In this study, we construct a full‐wave model to simulate the observed gravity wave structure. The model includes dissipation processes due to molecular viscosity, which increases exponentially with altitude, and eddy viscosity, which dominates the lower atmosphere. Using our model, we reproduced the observed temperature perturbations with the superposition of two gravity wave modes, one with λz = 600 km and λx = 1,600 km while the other with λz = 140 km and λx = 8,000 km. We estimate the thermal effects introduced by gravity waves and find that gravity waves below 900 km may significantly modify temperature structure of the upper atmosphere by tens of Kelvins. The wave‐induced thermal effect is sensitive to the eddy viscosity, which controls the dissipation and thermal conductivity below 900 km. When the eddy viscosity is increased by a factor of five, the thermal effect of gravity waves changes from −89 K cooling to nearly zero. This heating mechanism may contribute to the large temperature variability of 60 K in Titan's upper atmosphere. Plain Language Summary: Titan is the largest moon of planet Saturn. The Huygens probe observed a wave‐like temperature structure in Titan's upper atmosphere, but previous modeling studies are unable to reproduce this observed temperature fluctuation. In this study, we construct a 1‐dimensional model to simulate the gravity waves in Titan's atmosphere. Using this model, we successfully reproduce the temperature fluctuation pattern observed by the Huygens probe. We also find that the gravity waves can heat or cool Titan's atmosphere by tens of Kelvins when they travel upward and break into small eddies. The heating or cooling magnitude is highly sensitive to the turbulent level of the atmosphere. As a result, Titan's upper atmosphere can experience remarkable temperature changes as large as 60 K under very turbulent circumstances. Key Points: We construct a linearized full wave model to simulate the propagation and dissipation of gravity waves throughout Titan's atmosphereThe temperature fluctuations observed by Huygens/Huygens Atmospheric Structure Instrument between 500 and 1,000∼km are well reproduced by model calculationsGravity waves below 900 km may induce a temperature variability of several tens of Kelvins above 1000 km [ABSTRACT FROM AUTHOR]

The equatorial ionization anomaly (EIA) crest derived from GPS observations, F2‐layer peak height (hmF2), critical frequency (foF2), and equatorial electrojet (EEJ) in China low latitude are used to study the lunar tidal effect on EIA region for the years from 2006 to 2015. A predominant 14.76‐day periodic component in EIA crest, hmF2, and EEJ concurrently appears in some seasonal intervals, which coincides with the half of the lunar revolution period (29.53 days) and the lunar phase, indicating that the 14.76‐day periodic oscillation in EIA region is modulated by the lunar tide. This 14.76‐day periodic oscillation occurs in all Northern Hemisphere (NH) winter and corresponds to their respective sudden stratospheric warming (SSW) period from 2006 to 2015. In addition, this 14.76‐day periodic oscillation also occurs in other seasons for some years, for example, May and August, in which wave power is sometimes comparable to that in SSW period. The occurrence of the 14.76‐day periodic oscillation and its wave power during non‐SSW seasons in the solar maximum years (2012–2015) is more frequent and higher than that in the solar minimum years (2008–2010). Our results suggest that, besides the NH SSW condition, the solar activity and some other unclear factors are also responsible for the lunar tide enhancement in EIA region. Key Points: A consistent 14.76‐day periodic variation is revealed in equatorial ionization anomaly (EIA) location, hmF2, and equatorial electrojet in China EIA regionThis 14.76‐day periodic oscillation occurs not only in Northern Hemisphere winter (sudden stratospheric warming) but also in other seasonsThis 14.76‐day periodic oscillation is related to the semidiurnal lunar tides (M2) with a 12.42‐hr period [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is the primary malignant bone tumor. Despite therapeutic strategies including surgery, chemotherapy, and radiotherapy have been introduced into the war of fighting OS, the 5‐year survival rate for patients still remains unchangeable for decades. Besides, the critical bone defects after surgery, drug‐resistance and side effects also attenuate the therapeutic effects and predict poor prognosis. Recently, photothermal therapy (PTT) has attracted extensive attention featuring minimal invasiveness and high spatial‐temporal precision characteristics. Herein, an ultrathin 2D inorganic ancient pigment Egyptian blue decorated 3D‐printing scaffold (CaPCu) with profound PTT efficacy at the second near‐infrared (NIR‐II) biowindow against OS and enhanced osteogenesis performance is successfully constructed. Importantly, this work uncovers the underlying biological mechanisms that genes associated with cell death, proliferation, and bone development are regulated by CaPCu‐scaffold‐based therapy. This work not only elucidates the fascinating clinical translation prospects of CaPCu‐scaffold‐based PTT against OS in NIR‐II biowindow, but also demonstrates the potential mechanisms and offers a novel strategy to develop the next‐generation, multifunctional tissue‐engineering biomaterials. [ABSTRACT FROM AUTHOR]

Ionospheric plasma density data from the Planar Langmuir Probe onboard the CHAllenging Minisatellite Payload (CHAMP) are used to investigate the latitudinal profile of the ionospheric plasma density. Along with the well‐known profiles with features of the equatorial ionization anomaly and equatorial plasma bubbles, a third type is observed as smooth profiles with large‐scale deep equatorial trough (DET) where the plasma density is extremely low. A global survey focusing on magnetically quiet conditions reveals that the DET profiles are generally a post‐sunset phenomenon, and their appearance depends on longitude and season. During equinoxes in active solar years, the strong pre‐reversal enhancement electric field is believed to uplift the ionosphere and produce the DET profiles. While around June solstice, the DET profiles are clustered at 45°W–0° E longitude, where the zonal electric field is weak but the magnetic meridional component of the neutral wind is most significant. The SAMI2 model is then employed to simulate the ionospheric plasma distribution in the magnetic meridional plane with enhanced neutral wind, which successfully reproduced the main features of the observed DET profile. The results indicate that the neutral wind can obviously affect the equatorial ionosphere by transporting plasma in the magnetic flux tube through neutral‐ion interaction. The neutral wind is previously known to work with the inclined magnetic field at mid‐latitude, while this study emphasizes its effect around the magnetic equator especially when the electric field forcing (E×B) is weak or absent. Key Points: Deep equatorial trough (DET) occurs at night under weak upward plasma drift as well as under strong prereversal enhancementThe DET profiles is accompanied by higher equatorial hmF2, when either the E × B drift or strong magnetic meridional wind is presentModel simulation verifies that field‐aligned plasma transport driven by the neutral wind leads to the extremely low density at the equator [ABSTRACT FROM AUTHOR]

Few observations investigated the interaction between an electrical medium‐scale traveling ionospheric disturbance (EMSTID) and an equatorial plasma bubble (EPB). This paper presents another interaction between a southwestward propagating EMSTID and an eastward drifting EPB in the equatorial ionization anomaly (EIA) crest region of China. When the EMSTID and the EPB touched each other, several depletions of the EMSTID (EPB) showed the eastward (westward) velocity disturbances of the EPB (EMSTID) depletions. Besides, phase elongations of the EPB depletions contrarotated as the EMSTID propagated southwestward. However, of important finding is that the interaction of the EMSTID and the EPB could have polarized one depletion of the postmidnight EPB that should have become a fossilized bubble. Inside that polarized EPB depletion were meter‐scale irregularities that caused activated radar echoes and enhanced ranged spread F (RSF). The interaction occurred in descending ionosphere and the lower density regions got filled up with an enhanced density plasma. We propose that the EMSTID and the EPB could have electrically coupled with each other, causing an enhanced polarization electric field (PEF) that polarized that EPB depletion; the E × B gradient drift instability (Kelley, 1989) could have caused the meter‐scale irregularities when that enhanced PEF was imposed on that reactivated EPB depletion surrounded by that enhanced density plasma. This study provides observational evidence that how an electrical couple of EMSTID and EPB events can activate a postmidnight EPB depletion that should become a fossilized structure. Plain Language Summary: Otsuka et al. (2012, https://doi.org/10.1029/2012GL052286) provided the first report indicating the disappearance of an equatorial plasma bubble (EPB) airglow depletion after interaction with an electrical medium‐scale traveling ionospheric disturbance (EMSTID) airglow enhancement. For comparison, the current study reports a postmidnight airglow event in which an electrical coupling of an EMSTID and an EPB could have polarized one EPB airglow depletion that caused the activated radar echoes of very high frequency (VHF) radar and the enhanced ranged spread F (RSF) in descending ionosphere filled with an enhanced density plasma. Key Points: Interaction between an electrical medium‐scale traveling ionospheric disturbance (EMSTID) and an equatorial plasma bubble (EPB) in the equatorial ionization anomaly (EIA) crest region over ChinaElectrical coupling of the EMSTID and the EPB polarized one EPB depletion that caused activated radar echoes and enhanced ranged spread F (RSF)The interaction occurred in descending ionosphere and the lower density regions got filled up with an enhanced density plasma [ABSTRACT FROM AUTHOR]

During sudden stratospheric warming events, the ionosphere exhibits phase‐shifted semidiurnal perturbations, which are typically attributed to vertical coupling associated with the semidiurnal lunar tide (M2). Our understanding of ionospheric responses to M2 is limited. This study focuses on fundamental vertical coupling processes associated with the latitudinal extent and hemispheric asymmetry of ionospheric M2 signatures using total electron content data from the American sector. Our results illustrate that the asymmetry maximizes at 15°N and 20°S magnetic latitudes. In the Southern Hemisphere, the M2‐like signatures extend deep into midlatitude and encounter the Weddell Sea Anomaly. The time evolution of the Anomaly exhibits a distortion, which is attributed to an M2 modulation. The hemispheric asymmetry of M2 signatures in the low latitude can be primarily explained by the transequatorial wind modulation of the equatorial plasma fountain. Other physical processes could also be relevant, including hemispheric asymmetry of the M2 below the F‐region, the ambient thermospheric composition and ionospheric plasma distribution, and the geomagnetic field configuration. Plain Language Summary: Sudden stratospheric warming event is a meteorological phenomenon occurring mainly during the boreal winter, during which the polar temperature enhances and the polar vortex breaks. Recently, scientists have found that during such an event at stratospheric altitude, the ionosphere, which is tens and hundreds of kilometers higher than the stratosphere, exhibits featured perturbations in large ranges of longitude, latitude, and altitude. With electron density observations derived from the Global Positioning System during three boreal winter periods, this work studies the latitudinal variation and hemispheric asymmetry of ionospheric perturbations with semidiurnal lunitidal signatures, which are not well investigated in previous research works. Based on our observations, we specifically focus on analyzing how the lunar tide from the lower atmosphere affects up to the upper ionosphere. It is found that the ionospheric semidiurnal lunitidal signatures lean southward in the low latitudes and extend up to middle latitudes only in the Southern Hemisphere. We demonstrate that the low‐latitude asymmetry is mainly attributed to the wind that blows from the summer (Southern) to the winter (Northern) Hemisphere. The cause of the perturbations in the southern middle latitude is more complicated. We also find that an ionospheric phenomenon called the Weddell Sea Anomaly may also be influenced. Key Points: Ionospheric semidiurnal lunitidal signatures in the American sector exhibit hemispheric asymmetry during sudden stratospheric warmingsSuch asymmetry at low latitudes is due to the wind‐modulated fountain effect, and lunitidal signatures extend to southern midlatitudesThe in situ lunitidal wind potentially modulates the ionospheric Weddell Sea Anomaly [ABSTRACT FROM AUTHOR]

With the help of the high‐spatial‐resolution total electron content (TEC) data obtained by Mars Advanced Radar for Subsurface and Ionospheric Sounding on board the Mars Express (MEx) during June 2005 to September 2007, the detailed configurations of the Martian nightside ionosphere in crustal magnetic field cusp regions are researched in this paper. It is found that double‐peak structures of orbital observed TEC values frequently appeared when MEx was crossing through the strong crustal magnetic field cusp regions. This observational result implies that the Martian nightside TECs in the periphery of the cusp regions are generally higher than those in the central areas of the cusp regions, a phenomenon never reported before. By combining the TEC data with the in‐situ electron flux data obtained by the Analyzer of Space Plasma and Energetic Atoms‐3 (ASPERA‐3), it is found that the difference between the fluxes of the electrons precipitating in the central and peripheral areas of the cusp regions can be responsible for the observed TEC double‐peak structures. Plain Language Summary: Martian ionosphere on the nightside is an area far from well understood. According to previous researches, in areas with strong crustal magnetic fields, the Martian nightside ionosphere would be denser in cusp regions. However, in this research, we find that the Martian nightside total electron contents (TECs) in the center of the crustal magnetic cusp regions are generally lower than those in the periphery of the cusp regions. As far as we know, this phenomenon was never found before. By combining the TEC data with the observations on the precipitating electrons, we further find that the difference between the flux of the electrons precipitating in the center and periphery of the cusp regions can be responsible for this phenomenon. Our study shows a more detailed TEC structure in the cusp regions and suggests that the effects of the Martian crustal magnetic fields on the nightside ionosphere and plasma transfer are very complicated and need more researches. Key Points: Patterns of total electron content (TEC) near strong crustal magnetic fields in the Martian nightside ionosphere are investigatedDouble‐peaked TEC structures are observed ∼50% of the time in the open magnetic field regionsThe TEC double‐peak structures are associated with inhomogeneous patterns of precipitating electrons in these regions [ABSTRACT FROM AUTHOR]

Cancer metastases are the main causes for the high mortality of cancer. The current treatment modality for bone metastasis of breast cancer is dominantly destructive, which urges the engineering of multifunctional biomaterials, not only for eliminating primary/metastases tumors effectively but also for enhancing bone–tissue regeneration. Herein, an immune adjuvant (R837)‐loaded and niobium carbide (Nb2C) MXene‐modified 3D‐printing biodegradable scaffold (BG@NbSiR) is designed and constructed to effectively treat bone metastasis of breast cancer. The engineered BG@NbSiR scaffold can eradicate primary tumors, activate the immune response, suppress metastases, prevent tumor relapses (long‐term immunological memory) by synergizing with checkpoint blockade immunotherapy, and accelerate osteogenesis as evidenced by multiple in vivo murine models. In particular, single‐cell sequencing (scRNA‐seq) is employed to further determine the critical factors responding to BG@NbSiR scaffold‐based photothermia plus checkpoint blockade‐combined immunotherapy. Several gene functional terms are identified in both tumor biology (including copy number variation) and immune response, which further reveal the underlying therapeutic mechanisms from the perspective of single‐cell transcriptome. This work not only demonstrates the promising clinical application potentials of BG@NbSiR scaffold‐based therapy against bone metastasis of breast cancer, but also provides distinctive avenues to optimize the design and construction of multifunctional tissue‐engineering biomaterials based on single‐cell genomes. [ABSTRACT FROM AUTHOR]

In this paper, we first investigate the effects of a postevening Weddell Sea Anomaly (WSA)‐like plasma patch on a southwestward propagating medium‐scale traveling ionospheric disturbance (MSTID) over Xinglong, China (40.4°N, 117.6°E; Mlat. ~30.4°N). We found that some of this kind of WSA‐like plasma patches moved northward from the equatorial ionization anomaly (EIA) regions to midlatitudes, as they traveled westward into China. During 2012–2016, these plasma patches frequently occurred during the period of May–August with a monthly occurrence rate of over 20%, causing nighttime plasma density enhancements (NPDEs) in midlatitudes of China. Over 50% of these structures were accompanied by concurrent MSTID and Es. We propose that an intense polarization electric field (PEF) associated with an MSTID/Es from the more northern regions of EIA could frequently drive these plasma patches poleward. On the night of 27 June 2014 (Kp < 2−), either an MSTID and an intense Es layer (the maximum foEs >12 MHz) occurred at the onset of the poleward motion of a WSA‐like plasma patch, lending credence to this possibility. The observed plasma patch was pushed poleward to interact with the observed MSTID, causing some poleward extending C‐shaped airglow depletions/enhancements of the MSTID in a transition region where the ionosphere changed from a collapse region to an uplifted one. We attributed those poleward extending airglow depletions to the interaction between the MSTID and the plasma patch because of the secondary gradient drift instability and those of airglow enhancements to the redistribution of plasma. Plain Language Summary: This study found that postevening Weddell Sea Anomaly (WSA)‐like patchy plasma structures frequently occurred during May–August of 2012–2016 in the East Asian regions. Among these plasma patches, a small portion moved northward from the equatorial ionization anomaly (EIA) regions to midlatitudes, as they moved westward into China. On the magnetically quiet night of 27 June 2014 (Kp < 2−), such a plasma patch already moved westward and poleward to the midlatitude region of China, affecting the evolution/propagation of a southwestward propagating medium‐scale traveling ionospheric disturbance (MSTID). This paper, therefore, investigates the interaction between a midlatitude MSTID and a poleward moving WSA‐like plasma patch. We mainly investigate the possible physical mechanisms behind this kind of plasma patches and how they could affect the propagation/evolution of MSTIDs over midlatitudes of China. Key Points: Poleward extending C‐shaped airglow depletions/enhancements of MSTID were caused by interaction between an MSTID and a postevening WSA‐like plasma patchWestward and northward moving WSA‐like plasma patches frequently caused nighttime midlatitude plasma enhancements over Xinglong, ChinaAn intense PEF associated with an MSTID/Es from the more northern regions of EIA could frequently cause poleward motion of the WSA‐like plasma patch [ABSTRACT FROM AUTHOR]

Ti6Al4V scaffolds have high strength and corrosion resistance. 3D printing technology can optimize the pore structure of Ti6Al4V scaffolds, promoting bone tissue growth into the scaffolds to form firm osseointegrations. However, Ti6Al4V lacks biological activity. This defect can be overcome through surface modifications. Arc ion plating is employed to prepare titanium copper/titanium copper nitride (TiCu/Ti‐Cu‐N) multilayer coating, which is applied to 3D‐printed porous Ti6Al4V scaffolds by selective laser melting and bearing 300–400 µm pores. In addition to the excellent biological activity of copper, TiN shows superior corrosion resistance. The scaffold properties, osteogenesis, and osteointegration are evaluated in vitro and in vivo. Results show that human bone mesenchymal stem cells (hBMSCs) proliferate and adhere more effectively on coated scaffolds than on uncoated scaffolds. Further, the coating has a significant role in recruiting hBMSCs, and upregulation of the SDF‐1α/CXCR4 axis, p38 expression, and extracellular signal‐related kinase (Erk) and Akt signaling pathway. The in vitro results are further confirmed by an animal experiment in the New Zealand white rabbit femur tibia defect. Overall, the TiCu/Ti‐Cu‐N‐coated 3D‐printed Ti6Al4V scaffold shows excellent biocompatibility and bioactivity in promoting bone repair. The underlying mechanism may involve recruiting BMSCs and promoting their osteogenic differentiation. [ABSTRACT FROM AUTHOR]

The morphological difference of the northern equatorial ionization anomaly between the eastern Asian and American sectors is statistically studied with ground‐based total electron content data from 2000 to 2011. The intensity (Ic), latitudinal location (Lc), and occurrence time (Tc) of the daytime equatorial ionization anomaly crest are derived from daytime peak total electron content in time‐latitude plots. The main results are as follows. Lc in the two sectors exhibits an apparent difference, especially in solar minimum, during which Lc in the American sector shows an annual variation that is more poleward in northern summer and more equatorward in northern winter, while Lc in the eastern Asian sector shows a semiannual variation that is more poleward around equinoxes and more equatorward around solstices. Ic tends to be stronger in the eastern Asian sector than that in the American sector in all seasons, and this difference increases with the increase of the solar flux index. Tc tends to be earlier in northern winter and later in northern summer in both sectors and shows dependence on solar activity. We demonstrate that the seasonal variation of Lc in the American sector is not dominated by the ionospheric equatorial zonal electric field, and suggest that the difference of Lc between the two sectors is probably related to different meridional wind effects due to the displacement of geographic and magnetic equators. The Ic difference is probably related to the longitudinal wave number‐3 and ‐4 structures driven by tidal forcing from the 5lower atmosphere. Key Points: The seasonal variation of the northern EIA crest location is distinctly different between the eastern Asian and American sectorsSuch difference is probably related to the different meridional wind effects due to the displacement of geographic and magnetic equatorsThe EIA crest intensity tends to be stronger in the eastern Asian sector in all seasons that may be due to the nonmigrating tides [ABSTRACT FROM AUTHOR]

Variations of the low‐latitude ionosphere in the eastern Asian sector during the 2017 sudden stratospheric warming (SSW) were studied with multi‐instrumental observations that correspond to different altitudes. Specifically, the variations of the topside ionosphere as high as over 830 km were investigated with data from the Swarm B satellite (~500 km), the Defense Meteorological Satellite Program F15 satellite (~830 km), and the Meteorological Operational satellite‐A (~830 km). The main results are as follows. (1) Simultaneous variations were detected in the ionospheric parameters from the E region to the topside ionosphere around the first peak warming of the 2017 SSW. (2) These variations exhibited similar quasi‐16‐day (Q16D; ~14.5‐day) periods, and these periods were most significant just before the first peak warming. (3) These simultaneous Q16D variations were not due to the solar extreme ultraviolet irradiance or geomagnetic activities but were probably driven from below, by planetary waves or semidiurnal lunar tides that enhanced during the SSW. (4) The Q16D variation of the topside ionospheric electron density at ~830 km was probably driven not only by the upward mapping electric field modulated in the E region dynamo but also by the electric field modulated in the F region dynamo. Key Points: Multi‐instrumental observations at different altitudes were used to study the low‐latitude ionospheric variations during the 2017 SSWSimultaneous ~14.5‐day periodic variations were detected at different ionospheric heights from the E region to the topside ionosphereThe ~14.5‐day ionospheric variations at ~830 km were probably driven by not only the fountain effect but also the F region dynamo process [ABSTRACT FROM AUTHOR]

Superior to chemotherapy, photonic hyperthermia and targeted therapy have made attractive impacts on cancer treatment by virtue of their profound advantages such as high specificity and minimal invasiveness, but the rational integration of corresponding therapeutic drugs for achieving concurrent photothermal ablation/targeted therapy is still challenging. Herein, a self‐assembled nanomedicine Anlotinib@IR820 is constructed with drug formulations for highly efficient and synergistic photonic hyperthermia and targeted therapy against breast cancer. Specifically, the constructed Anlotinib@IR820 nanomedicine presents high accumulation at the tumor site owing to the enhanced permeability and retention effect and simultaneously overcomes the obstacles of poor water solubility of Anlotinib (for targeted therapy) and the short lifetime of IR820 (for photonic ablation). The photothermal ablation as activated by near‐infrared laser can not only irradiate cancer cells but also promote the cellular uptake of Anlotinib, which presents a profound synergistic function both in vitro and in vivo. Mechanically, Anlotinib@IR820 nanomedicine can induce apoptosis and cause cell cycle arrest in breast cancer through inhibiting ERK, AKT, and STAT3 pathways. Therefore, the rationally designed drug‐composed Anlotinib@IR820 nanomedicine exhibits high clinical translation potential because of its therapeutic nanoformulation, which provides an alternative option for efficient combinational therapy of breast cancer. [ABSTRACT FROM AUTHOR]

In situ electron density measurements by the CHAllenging Minisatellite Payload and the Defense Meteorological Satellites Program F17 satellites show that the midlatitude ionization at altitudes of ∼350 and 850 km is enhanced in the late evening. The enhancements increase to maximum around midnight and are clearly observed till early morning as the equatorial ionization decays to minimal level. They appear in the winter hemisphere during June and December solstices and in both hemispheres during equinox. The enhancements are well confined between ±30° and ±50° magnetic latitude, with the magnetic flux tubes of L = 1.3 − 2.4 connecting to the plasmasphere. Furthermore, coincident longitudinal variations exist in both the ionospheric enhancements and the plasmaspheric total electron content, especially during the solstice months. The coincidence may suggest essential plasma transport between the ionosphere and the plasmasphere. These facts support the idea that the plasmasphere provides extra plasma to the midlatitude ionosphere through downward plasma influx along the magnetic field lines to form the nighttime ionization enhancements when the sunlight is absent. Key Points: Satellites reveal global pictures of nighttime enhancements in the midlatitude ionosphere at altitude of ∼350 and 850 kmWe find correlation of longitudinal dependence between the ionospheric enhancements and the plasmasphereThe plasmasphere is suggested to feed and dominate the formation of the nighttime enhancements [ABSTRACT FROM AUTHOR]

ABSTRACT Prospective studies that have examined the association between physical activity and fracture risks have reported conflicting findings. We performed a meta-analysis to evaluate this association. We searched MEDLINE (1966 to February 1, 2013), EMBASE (1980 to February 1, 2013), and OVID (1950 to February 1, 2013) for prospective cohort studies with no restrictions. Categorical, heterogeneity, publication bias, and subgroup analyses were performed. There were 22 cohort studies with 1,235,768 participants and 14,843 fractures, including 8874 hip, 690 wrist, and 927 vertebral fractures. The pooled relative risk (RR) of total fractures for the highest versus lowest category of physical activity was 0.71 (95% confidence interval [CI], 0.63-0.80). The analysis of fracture subtypes showed a statistically significant inverse relationship between a higher category of physical activity and risk of hip and wrist fracture. The risk of hip or wrist fracture was 39% and 28% lower, respectively, among individuals with the highest category of physical activity than among those with the lowest category (95% CI, 0.54-0.69 and 0.49-0.96, respectively). The association between physical activity and vertebral fracture risk was not statistically related (RR, 0.87; 95% CI, 0.72-1.03). There was no evidence of publication bias. There was a statistically significant inverse association between physical activity and total fracture risk, especially for hip and wrist fractures. Additional subject-level meta-analyses are required for a more reliable assessment of subgroups and types of physical activity. © 2014 American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Damaged bone is sensitive to mechanical stimulation throughout the remodeling phase of bone healing. Muscle damage and muscular atrophy associated with open fractures and subsequent fixation are not beneficial to maintaining optimum conditions for mechanical stability. The aim of this study was to investigate whether local muscle atrophy and dysfunction affect fracture healing in a rat femur fracture model. We combined the rat model of a short period atrophy of the quadriceps with femur fracture. Forty-four-month-old male Wistar rats were adopted for this study. Two units of botulinum toxin-A (BXTA) were administered locally into the right side of the quadriceps of each rat, while the same dose of saline was injected into the contralateral quadriceps. After BXTA had been fully absorbed by the quadriceps, osteotomy was performed in both femurs with intramedullary fixation. Gross observation and weighing of muscle tissue, X-ray analysis, callus histology, and bone biomechanical testing were performed at different time points up to 8 weeks post-surgery. Local injection of BXTA led to a significant decrease in the volume and weight of the quadriceps compared to the control side. At the eighth week, the left side femurs of the saline-injected quadriceps almost reached bony union, and fibrous calluses were completely calcified into woven bone. However, a gap was still visible in the BXTA-treated side on X-ray images. As showed by bone histology, there were no mature osseous calluses or woven bone on the BXTA-treated side, but a resorption pattern was evident. Biomechanical testing indicated that the femurs of the BXTA-treated side exhibited inferior mechanical properties compared with the control side. The inferior outcome following BXTA injection, compared with saline injection, in terms of callus resistance may be the consequence of unexpected load and mechanical unsteadiness caused by muscle atrophy and dysfunction. © 2011 Orthopaedic Research Society. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:574-580, 2012 [ABSTRACT FROM AUTHOR]

Yearly averaging is a basic preprocessing of ionospheric data to smooth out the short‐term, cyclic variations in the observations. However, we find that the use of yearly (running) average method probably leads to a biased evaluated relation between the ionospheric parameters (e.g., F2 peak electron density, NmF2) and the solar extreme ultraviolet (EUV) irradiance. The bias is essentially related to the annual/seasonal variations of the ionosphere, which means that the ionospheric sensitivity to the solar EUV irradiance varies with season and the same solar input can produce different ionization levels in different months/seasons. The yearly method simply averages the observations of different seasons, leading to a biased yearly NmF2‐EUV relation, which will further affect the estimation of the ionospheric hysteresis (different NmF2‐EUV relation in the solar rising and declining phase). Also, the extraction of long‐term trends in the ionosphere will be more uncertain if using a regression approach based on the biased NmF2‐EUV relation. In conclusion, we suggest to do the analysis month by month (using monthly average method) to properly deal with the annual/seasonal variations of the ionosphere, and to obtain accurate estimation of the hysteresis and long‐term trends. Though both the yearly and monthly methods were used in precedent works, the bias introduced by the yearly average method has not been fully recognized prior to this study. Key Points: Improper use of yearly average method causes uncertainty in the determined ionosphere‐EUV relationEvaluation of ionospheric hysteresis and long‐term trends is probably biased due to the uncertaintyMonthly analysis is a better method to avoid the uncertainty/bias essentially related to strong seasonal variations of the ionosphere [ABSTRACT FROM AUTHOR]

Sonodynamic therapy (SDT) is noninvasive and possesses high body‐penetration depth, showing great potential for the treatment of deep‐seated solid tumors. The efficacy of SDT, however, is limited by widespread hypoxia in solid tumors. Given this, an ultrasound‐activated nanosystem is developed by integrating ferrate(VI) and protoporphyrin IX into biodegradable hollow mesoporous organosilica nanoplatforms, followed by assembling a phase‐change material of lauric acid. The ferrate(VI) effectively reacts with water as well as overexpressed hydrogen peroxide and glutathione (GSH) in tumor cells, leading to tumor‐microenvironment‐independent oxygen production and in situ GSH depletion in tumors. More importantly, significant reactive oxygen species (ROS) overproduction is simultaneously achieved by protoporphyrin‐augmented SDT and intracellular Fenton chemistry. Furthermore, the mild hyperthermia induced by ultrasound can trigger the phase change of lauric acid, achieving ultrasound‐responsive control over the release of oxygen and ROS, and the depletion of GSH. The simultaneous oxygen generation, in situ GSH depletion, and ROS overproduction play a synergetic role in sensitizing SDT toward hypoxic solid tumors, which is verified by the remarkable improvement of hypoxic environments and more significant growth inhibition of SDT against osteosarcoma both in vitro and in vivo, showing promising application in hypoxic solid tumor treatment. [ABSTRACT FROM AUTHOR]