The effect of continuous geomagnetic storms on enhancements of ultrarelativistic electrons in the Earth’s outer radiation belt

Ultrarelativistic electrons (Ek > 3 MeV) are the most energetic electrons in the Earth’s outer radiation belt, which can cause serious damage to equipments on satellites. The evolutions of ultrarelativistic electrons during geomagnetic storm have been well understood, but the effects of continuous geomagnetic storm on ultrarelativistic electrons are still unclear. Using the data of the Van Allen Probes, we study the evolutions of ultrarelativistic electrons in the Earth’s outer radiation belt during the three continuous geomagnetic storm events. These continuous geomagnetic storm events include the two geomagnetic storms. During the recovery phase of the first geomagnetic storm, enhanced relativistic and ultrarelativistic electrons with lower energies (≥ 3.4 MeV) are observed. These enhanced relativistic electrons could be the source of ultrarelativistic electrons and contribute to ultrarelativistic electron acceleration during the second geomagnetic storm. While 3.4 MeV electrons could be further enhanced during the second geomagnetic storm. During the recovery phase of the second small or moderate geomagnetic storm, ultrarelativistic electrons with higher cutoff energies (≥ 5.2 MeV) and higher fluxes are observed. Compared to an isolated geomagnetic storm with similar solar wind and geomagnetic conditions, ultrarelativistic electrons with higher cutoff energies and higher fluxes are observed during the recovery phase of the second geomagnetic storm. We also find that continuous geomagnetic storm events may contribute even more to enhancements of ultrarelativistic electrons in the outer radiation belt if the second geomagnetic storm is a small or moderate storm with a low solar wind dynamic pressure and short-duration main phase. These can help us to further understand the evolutions of ultrarelativistic electrons in the Earth’s outer radiation belt during geomagnetic storms

Effects of Qi-Fang-Xi-Bi-Granules on Cartilage Morphology and C/ebp α

Objective. To investigate the effects of Qi-Fang-Xi-Bi-Granules (QFXBGs) on cartilage morphology and methylation of C/ebpα (CCAAT/enhancer binding proteinα) at the promoter region. Methods. Knee osteoarthritis (KOA) modeling was performed in rats in accordance with Hulth’s method, and control group received sham operation. Eight weeks after KOA modeling, the rats in the KOA modeling group were further divided into 6 groups. Each group was given the appropriate drug. After 8 weeks, half of the rats were used for Micro-CT scan, HE staining, ABH/OG staining, immunohistochemistry, and TUNNEL staining of the knee joint tissue, and the other half were used to examine C/ebpα promoter methylation. Results. The three dose groups of QFXBGs all showed lower degrees of surface fissures and flaking, thicker cartilage layer, and restored chondrocyte and subchondral bone morphology, compared with the KOA model group. C/ebpα-22 promoter methylation levels in the high- and low-dose groups were significantly higher than that in the KOA modeling group (p<0.05), while C/ebpα-2 promoter methylation level in the medium-dose group was significantly higher than that in the KOA modeling group (p<0.05). Conclusions. QFXBGs may alleviate articular cartilage degeneration through promoting C/ebpα-2 or C/ebpα-22 methylation at specific promoter sites

Identification of a basement membrane-related gene signature for predicting prognosis, immune infiltration, and drug sensitivity in colorectal cancer

BackgroundColorectal cancer (CRC) is the most common malignancy affecting the gastrointestinal tract. Extensive research indicates that basement membranes (BMs) may play a crucial role in the initiation and progression of the disease.MethodsData on the RNA expression patterns and clinicopathological information of patients with CRC were sourced from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. A BM-linked risk signature for the prediction of overall survival (OS) was formulated using univariate Cox regression and combined machine learning techniques. Survival outcomes, functional pathways, the tumor microenvironment (TME), and responses to both immunotherapy and chemotherapy within varying risk classifications were also investigated. The expression trends of the model genes were evaluated by reverse transcription polymerase chain reaction (RT-PCR) and the Human Protein Atlas (HPA) database.ResultsA nine-gene risk signature containing UNC5C, TINAG, TIMP1, SPOCK3, MMP1, AGRN, UNC5A, ADAMTS4, and ITGA7 was constructed for the prediction of outcomes in patients with CRC. The expression profiles of these candidate genes were verified using RT-PCR and the HPA database and were found to be consistent with the findings on differential gene expression in the TCGA dataset. The validity of the signature was confirmed using the GEO cohort. The patients were stratified into different risk groups according to differences in clinicopathological characteristics, TME features, enrichment functions, and drug sensitivities. Lastly, the prognostic nomogram model based on the risk score was found to be effective in identifying high-risk patients and predicting OS.ConclusionA basement membrane-related risk signature was constructed and found to be effective for predicting the prognosis of patients with CRC

The Effects of the Content of NiO on the Microstructure and Photocatalytic Activity of the NiO/TiO2 Composite Film

The NiO/TiO2 composite films with the NiO content of 3 %, 5 %, 10 %, 13 %, 15 % and 20 % were prepared by mechanical coating technology and subsequent oxidation process. The composition and microstructure of the films were analyzed by X-ray Diffraction (XRD), scanning electron microscope (SEM), and energy dispersive spectroscopy (EDS). The photocatalytic activity was evaluated and the effects of the content of NiO on microstructure and photocatalytic activity of the films were studied. The results show that NiO particles are dispersed in the Ti coatings, and the NiO concentration in the inner layer of the coatings is higher than in the outer layer. With the addition of NiO in the NiO/Ti coating, the ductility is deteriorated and the thickness is reduced of the NiO/Ti coatings. The films with NiO/TiO2/Ti composite microstructure are obtained by the oxidation of NiO/Ti coatings. Photocatalytic efficiency of the films is obviously enhanced with the help of the p-n junction heterostructure in the NiO/TiO2 films. The optimum content of NiO is about 13 %, and the degradation rate of methyl orange solution reaches the maximum value of 88.44 %. DOI: http://dx.doi.org/10.5755/j01.ms.24.4.19266</p

Observation of Many-body Dynamical Delocalization in a Kicked Ultracold Gas

Contrary to a driven classical system that exhibits chaos phenomena and diffusive energy growth, a driven quantum system can exhibit dynamical localization that features energy saturation. However, the evolution of the dynamically localized state in the presence of many-body interactions has long remained an open question. Here we experimentally study an interacting 1D ultracold gas periodically kicked by a pulsed optical lattice, and observe the interaction-driven emergence of dynamical delocalization and many-body quantum chaos. The observed dynamics feature a sub-diffusive energy growth manifest over a broad parameter range of interaction and kick strengths, and shed light on an area where theoretical approaches are extremely challenging.Comment: 14 pages, 11 figures including supplementary material