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A COnstellation of Radiation BElt Survey (CORBES) program is proposed by the Sub-Group on Radiation Belt (SGRB) of TGCSS, COSPAR. To address the open qustions about the dynamics of the Earth’s radiation belt, CORBES mission would use a constellation of small/CubeSats to take an ultra-fast survey of the Earth’s radiation belt. The concept, science objectives and preliminary technical design of CORBES are introduced. This mission is an international multilateral cooperation mission coordinated by COSPAR. The SGRB Science Activities and COSPAR HQs Coordinate Activities on CORBES are summaried.

Chronic inflammation at diabetic wound sites results in the uncontrolled accumulation of pro‐inflammatory factors and reactive oxygen species (ROS), which impedes cell proliferation and delays wound healing. To promote the healing of diabetic wounds, chitosan/gelatin hydrogels containing ceria nanoparticles (CNPs) of various sizes were created in the current study. CNPs' efficacy in removing O2•−, •OH, and H2O2 was demonstrated, and the scavenging ability of CNPs of varying sizes was compared. The in vitro experiments demonstrated that hydrogels containing CNPs could effectively protect cells from ROS‐induced damage and facilitate mouse fibroblast migration. Furthermore, during the treatment of diabetic wounds in vivo, hydrogels containing CNPs exhibited anti‐inflammatory activity and could reduce the expression of the pro‐inflammatory factors TNF‐α (above 30%), IL‐6 (above 90%), and IL‐1β (above 80%), and effectively promote wound closure (above 80%) by inducing re‐epithelialization, collagen deposition, and angiogenesis. In addition, the biological properties and therapeutic effects of hydrogels containing CNPs of various sizes were compared and discussed. The finding revealed that hydrogels with 4 nm CNPs exhibited more significant biological properties and had implications for diabetic wound treatment. [ABSTRACT FROM AUTHOR]

Insect herbivory plays a critical role in the regulation of plant populations and community structures. Although the strength of insect herbivory varies with neighbouring tree diversity and identity, it is not clear to what extent insect guilds and leaf traits of host plants mediate the relationships, particularly in diverse natural forests.In this study, we measured leaf herbivory by chewing and mining insect herbivores in 442 saplings of nine species of deciduous trees in a warm‐temperate montane forest. We censused neighbouring trees and measured five leaf traits known to influence herbivory (i.e. specific leaf area‐SLA, thickness, carbon: nitrogen ratio‐C:N ratio, sodium‐Na and silicon‐Si content) on a subset of saplings.Only herbivory by leaf‐mining insects was influenced by the identity and diversity of neighbouring trees. Specifically, the incidence of leaf‐miners decreased with the phylogenetic diversity of neighbouring trees and increased with conspecific adult density in the vicinity of focal trees. Furthermore, leaf mining herbivory was positively correlated with the amount of Si in the leaves of focal saplings, and leaf chewing herbivory decreased with increasing C:N ratio in the leaves. In contrast to our hypothesis, the leaf traits of focal saplings did not serve as a functional link between tree diversity and insect herbivory.Synthesis: Overall, this study highlights the importance of considering the specialisation of insect herbivores in understanding the impacts of the diversity and identity of neighbouring trees on the strength of insect herbivory. [ABSTRACT FROM AUTHOR]

Rapid relativistic electron enhancements (REE) in the outer radiation belt have long been an intriguing phenomenon for space weather. In this study, we investigate rapid REE from October 2012 to December 2017 using multi‐spacecraft observations. A total of 27 rapid REE events are identified from the Van Allen Probes (RBSP) measurements with a 5 times increase of MeV electrons at the center of the outer radiation belt (L = 4.5–5.5) in a half RBSP orbit (∼4.5 hr). All REE events are found to be in association with pulse‐like injections of MeV electrons in the outer radiation belt. Electron fluxes in each injection at L ∼ 6.6 and the overall electron enhancements at L = 4.5–5.5 are quantified. The 500 keV and 0.8–1 MeV electron fluxes are correlated in injections and in overall enhancements. Substorm strength is more intense before/during the REE than intervals after the REE. The statistical study suggests that substorm‐associated MeV electron injections are highly correlated with rapid REE in the outer radiation belt. Plain Language Summary: Rapid relativistic electron enhancements (REE) in the outer radiation belt are one of the most important phenomena in space weather. The fast increases of MeV energy electrons can have significant impacts on satellite operations and safety. In this study, we identify 27 events of relativistic electron enhancements in which MeV electron increases five times in ∼4.5 hr at a radial distance of 4.5–5.5 Earth radius. All REE events are found in association with multiple pulse‐like injections of MeV electrons. The electron fluxes during each injection at geosynchronous altitude and the overall enhancements in the center of the radiation belt are quantified. The increases in sub‐relativistic and MeV electron fluxes are highly correlated. Overall, this research provides insights into the correlation between substorm‐associated MeV electron injections and the rapid intense REE in the outer radiation belt, contributing to a better understanding of the dynamics and processes involved in the radiation belt particle energization. Key Points: All 27 events of rapid enhancement of relativistic electrons are found to be associated with injections of MeV electronsThe 500 keV and 0.8–1 MeV electron fluxes are highly correlated during injections at L ∼ 6.6 and in overall enhancements at L = 4.5–5.5Substorm strength is more intense during rapid relativistic electron enhancements [ABSTRACT FROM AUTHOR]

Distributed radar systems promise to significantly enhance target localization by virtue of the superiority of multi-view observations from widely separated radars, compared to their monostatic counterparts. Nevertheless, when the radar number is limited, performing target localization bears the brunt of the parameter identifiability requirement that the parameter number must be no less than the number of independent measurements. In this way, the canonical two-stage target localization method, as well as its developments, is no longer appropriate for direct application. Hence, in this paper, we propose a novel target localization method using time-difference-of-arrival (TDOA) measurements with the minimum number of radars under platform position uncertainties. The referred distributed system is a bistatic multi-receiver system, where the primary signal is transmitted by a geostationary Earth orbit (GEO) satellite while receivers are equipped on several unmanned aerial vehicles (UAVs). In the first stage, the reference range from the reference radar to the target is estimated by a quadratic function, and then the weighted least squares (WLS) solution of the target location is updated by substituting the range estimate back into it. In the second stage, we invoke the Taylor series approximation to further refine the target localization obtained by the first stage. It can be foreseen that the developed method is beneficial for scenarios with a limited number of radars, including engineering projects such as fire control, surveillance, and guidance, to support high-accuracy target localization. The simulation results show the superiority of the localization performance of the proposed method over other existing methods. [ABSTRACT FROM AUTHOR]

Heat stroke and severe fever cause anemia, although the underlying mechanism remains unclear. Here, we report the use of Cerium oxide nanoparticles in protection of red blood cells against damage caused by exposure to short-term hyperthermia (42°C, 10 min). Red blood cells exposed to hyperthermia exhibited extradition senescence with higher density, smaller size and lower zeta potential relative to those under normal physiological environment (37°C, 10 min). Furthermore, hyperthermia-exposed cells exhibited significantly higher reactive oxygen species (ROS) production compared to the normal conditions. Importantly, the preconditional treatment, using Ceria nanoparticles (CNPs), ameliorated senescence and apoptosis in red blood cells damaged by hyperthermia by reducing ROS levels. Summarily, short-term hyperthermia caused a significant increase in ROS in red blood cells, and resulted in senescence and apoptosis. These may be possible mechanisms of pathological changes in red blood cells exposed to heat stroke or severe fever. Overall, these findings indicate that CNPs strongly inhibit ROS production, and effectively ameliorates hyperthermia-induced damages in red blood cells. [ABSTRACT FROM AUTHOR]