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Background: Muscle-invasive bladder cancer (MIBC) is a lethal disease with poor treatment response and a high death rate. Immune cells infiltrating the tumor tissues have been shown to play a vital role in tumorigenesis and tumor progression, but their prognostic significance in MIBC remains unclear. Objectives: To explore the landscape and prognostic significance of tumor-infiltrating immune cells (TIICs) in MIBC, and to develop a model to improve the prognostic predictions of MIBC. Methods and Materials: The gene expression profile and clinical data of MIBC patients were downloaded from the Gene Expression Omnibus and The Cancer Genome Atlas portal. The fractions of 22 TIIC subtypes were calculated using the Cell Type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm. A TIICs-based model was constructed using least absolute shrinkage and selection operator (LASSO) Cox regression in a training cohort and validated in the validation cohort. Results: Ten types of TIICs demonstrated different infiltration abundance between MIBC and normal tissue. We also found 11 types of TIICs that were significantly associated with overall survival (OS). A TIICs-based model was established, consisting of 15 types of immune cells, and an immunoscore was calculated. Significant differences in OS were found between the high and low immunoscore groups, in both training (n = 343) and validation (n = 146) cohorts. The model could identify patients who would have worse OS despite having similar clinical characteristics. Furthermore, multivariate analysis identified the immunoscore as an independent risk factor (hazard ratio, 3.23; 95% confidence interval; 2.22-4.70) for OS in MIBC patients. Conclusion: The landscape of immune infiltration is different between MIBC and normal tissue. The TIICs-based model could provide promising predictive value to complement the existing staging system for predicting the OS of MIBC patients.

Magnetar is a kind of pulsar powered by magnetic field energy. Part of the X-ray luminosities of magnetars in quiescence have a thermal origin and can be fitted by a blackbody spectrum with temperature kT ～ 0.2－0.6 keV, much higher than the typical values for rotation-powered pulsars. The observation and theoretical study of magnetar are one of hot topics in the field of pulsar research. The activity and emission characteristics of magnetar can be attributed to internal superhigh magnetic field. According to the work of WGW19 and combining with the equation of state, we first calculate the electric conductivity of the crust under a strong magnetic field, and then calculate the toroidal magnetic field decay rate and magnetic energy decay rate by using an eigenvalue equation of toroidal magnetic field decay and considering the effect of general relativity. We reinvestigate the LX-Lrot relationship of 22 magnetars with persistent soft X-ray luminosities and obtain two new fitting formulas on LX-Lrot. We find that for the magnetars with LX < Lrot, the soft X-ray radiations may originate from their rotational energy loss rate, or from magneto-sphere flow and particle wind heating. For the magnetars with LX > Lrot, the Ohmic decay of crustal toroidal magnetic fields can provide their observed isotropic soft X-ray radiation and maintain higher thermal temperature.As for the initial dipole magnetic fields of magnetars, we mainly refer to the rersearch by Viganò et al. (Viganò D, Rea N, Pons J A, Perna R, Aguilera D N, Miralles J A 2013 Mon. Not. R. Astron. Soc. 434 123), because they first proposed the up-dated neutron star magneto-thermal evolution model, which can successfully explain the X-ray radiation and cooling mechanism of young pulsars including magnetars and high-magnetic field pulsars. Objectively speaking, as to the decay of toroidal magnetic fields, there are some differences between our theoretical calculations of magnetic energy release rates and the actual situation of magnetic field decay in magnetars, this is because the estimate of initial dipolar magnetic field, true age and the thickness of inner crust of a magnetar are somewhat uncertain. In addition, due to the interstellar-medium’s absorptions to soft X-ray and the uncertainties of distance estimations, the observed soft X-ray luminosities of magnetars have certain deviations. With the continuous improvement of observation, equipment and methods, as well as the in-depth development of theoretical research, our model will be further improved, and the theoretical results are better accordant with the high-energy observation of magnetars.We also discuss other possible anisotropy origins of soft X-ray fluxes of magnetars, such as the formation of magnetic spots and thermoplastic flow wave heating in the polar cap. Although anisotropic heating mechanisms are different from Ohmic decay, all of them require that there exist strong toroidal magnetic fields inside a magnetar. However, the anisotropic heating mechanisms require higher toroidal multipole fields inside a magnetar (such as magnetic octupole field) and are related to complex Hall drift: these may be our research subjects in the future.

Silicon carbide (SiC), as a representative of the third-generation semiconductor materials, is widely used in some fields which may suffer strong radiation such as in the cases of military affairs, aerospace and reactor. SiC possesses the superior radiation-resistance characteristic. However, SiC under the proton irradiation generate a lot of defects, resulting in degradation of device performance and even complete loss of its function. Therefore, the study on the irradiation damage to SiC under proton irradiation possesses important significance. A large number of studies have shown that for most of electronic devices and different types of incident particles, the degradation of device performance caused by displacement damage is linearly dependent on non-ionizing energy loss (NIEL), so the displacement damage can be evaluated by NIEL. In this work, the Monte Carlo software Geant4 is used to simulate the relationship between NIEL and proton energy, and the variation of NIEL with the depth of the material and the contribution of different types of primary recoil atoms to the total NIEL are also studied. The NIEL simulation results show that the NIEL in SiC material is less than that in Si and Ga semiconductor material under the same proton irradiation, proving that the stability and the radiation-resistance of SiC are stronger. The simulation results of NIEL at different depths show that the most serious damage regions of the material under different energy protons are diverse. Under the irradiation of low energy proton, the most serious region of the displacement damage occurs at the end of the proton range. With the increase of proton energy, the worst damage region of material will gradually move from the end of the proton range to the surface of SiC material. According to the contribution of different types of primary recoil atoms to the total NIEL, when the energy of the incident proton is low, the displacement damage of the proton in the SiC is mainly caused by 28Si and 12C, and the damage caused by 28Si is obviously higher than that by 12C. As the energy of proton increases, the 28Si and 12C are still the main causes of Bragg peak of the NIEL at the end of the proton range, but the number of ions generated by nuclear reactions increases accordingly, and the displacement damage caused by these ions increases in the shallow area of SiC, leading the surface of the material to be the worst damaged region. The combination of the two factors caused the most serious damage region moves from the end of the proton range to the surface of the material with the increase of proton energy. The results of this study are useful for the application of SiC devices to irradiation environment.

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