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Electromagnetic wave (EMW) absorbing materials play a vital role in modern communication and information processing technologies to inhibit information leakage and prevent possible damages to environment and human bodies. Currently, most of EMW absorbing materials are either composites of two or more phases or in the form of nanosheets, nanowires or nanofibers in order to enhance the EMW absorption performance through dielectric loss, magnetic loss and dielectric/magnetic loss coupling. However, the combination of complex shapes/multi phases and nanosizes may compound the difficulties of materials processing, composition and interfaces control as well as performance maintenance during service. Thus, searching for single phase materials with good stability and superior EMW absorbing properties is appealing. To achieve this goal, the EMW absorbing properties of transition metal carbides TMCs (TM=Ti, Zr, Hf, Nb and Ta) and high entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C which belong to ultrahigh temperature ceramics, were investigated in this work. Due to the good electrical conductivity and splitting of d orbitals into lower energy t2g level and higher energy eg level in TMC6 octahedral arrangement, TMCs (TM=Ti, Zr, Hf, Nb and Ta) exhibit good EMW absorbing properties. Especially, HfC and TaC exhibit superior EMW absorbing properties. The minimum reflection loss (RLmin) value of HfC is −55.8 dB at 6.0 GHz with the thickness of 3.8 mm and the effective absorption bandwidth (EAB) is 6.0 GHz from 12.0 to 18.0 GHz at thickness of 1.9 mm; the RLmin value of TaC reaches −41.1 dB at 16.2 GHz with a thickness of 2.0 mm and the EAB is 6.1 GHz with a thickness of 2.2 mm. Intriguingly, the electromagnetic parameters, i.e., complex permittivity and permeability are tunable by forming single phase solid solution or high entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C. The RLmin value of high entropy (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C is −38.5 dB at 9.5 GHz with the thickness of 1.9 mm, and the EAB is 2.3 GHz (from 11.3 to 13.6 GHz) at thickness of 1.5 mm. The significance of this work is that it opens a new window to design single phase high performance EMW absorbing materials by dielectric/magnetic loss coupling through tuning the conductivity and crystal field splitting energy of d orbitals of transition metals in carbides, nitrides and possibly borides.

Background Recent studies have reported that COVID-19 infected patients with stroke, who were often in the older age group, had a higher incidence of vascular risk factors, and more severe infection related respiratory symptoms. These observations provided little evidence to suggest that COVID-19 infection is a potential causative factor for stroke. This report describes a young patient with a cerebellar stroke secondary to COVID-19 infection. Case presentation A 45-year old male presented at a hospital, reporting a two-day history of headache, vertigo, persistent vomiting, and unsteady gait. Physical examination revealed gaze-evoked nystagmus on extraocular movement testing, left-sided dysmetria and dysdiadochokinesia. He was diagnosed with a left cerebellar stroke. An external ventricular drain was inserted, and sub-occipital craniectomy was performed to manage the effects of elevated intracranial pressure due to the extent of oedema secondary to the infarct. He also underwent screening for the COVID-19 infection, which was positive on SARS-COV-2 polymerase chain reaction testing of his endotracheal aspirate. Blood and cerebrospinal fluid samples were negative. After the surgery, the patient developed atrial fibrillation and had prolonged vomiting symptoms, but these resolved eventually with symptomatic treatment. He was started on aspirin and statin therapy, but anticoagulation was withheld due to bleeding concerns. The external ventricular drain was removed nine days after the surgery. He continued with active rehabilitation. Conclusions Young patients with COVID-19 infection may be more susceptible to stroke, even in the absence of risk factors. Standard treatment with aspirin and statins remains essential in the management of COVID-19 related stroke. Anticoagulation for secondary prevention in those with atrial fibrillation should not be routine and has to be carefully evaluated for its benefits compared to the potential harms of increased bleeding associated with COVID-19 infection.

Insufficient vaccine doses and the lack of therapeutic agents for yellow fever put global health at risk, should this virus emerge from sub-Saharan Africa and South America.In phase 1a of this clinical trial, we assessed the safety, side-effect profile, and pharmacokinetics of TY014, a fully human IgG1 anti-yellow fever virus monoclonal antibody. In a double-blind, phase 1b clinical trial, we assessed the efficacy of TY014, as compared with placebo, in abrogating viremia related to the administration of live yellow fever vaccine (YF17D-204; Stamaril). The primary safety outcomes were adverse events reported 1 hour after the infusion and throughout the trial. The primary efficacy outcome was the dose of TY014 at which 100% of the participants tested negative for viremia within 48 hours after infusion.A total of 27 healthy participants were enrolled in phase 1a, and 10 participants in phase 1b. During phase 1a, TY014 dose escalation to a maximum of 20 mg per kilogram of body weight occurred in 22 participants. During phases 1a and 1b, adverse events within 1 hour after infusion occurred in 1 of 27 participants who received TY014 and in none of the 10 participants who received placebo. At least one adverse event occurred during the trial in 22 participants who received TY014 and in 8 who received placebo. The mean half-life of TY014 was approximately 12.8 days. At 48 hours after the infusion, none of the 5 participants who received the starting dose of TY014 of 2 mg per kilogram had detectable YF17D-204 viremia; these participants remained aviremic throughout the trial. Viremia was observed at 48 hours after the infusion in 2 of 5 participants who received placebo and at 72 hours in 2 more placebo recipients. Symptoms associated with yellow fever vaccine were less frequent in the TY014 group than in the placebo group.This phase 1 trial of TY014 did not identify worrisome safety signals and suggested potential clinical benefit, which requires further assessment in a phase 2 trial. (Funded by Tysana; ClinicalTrials.gov number, NCT03776786.).

Additional file 1: Section S1. In vivo toxicity experiments. Fig. S1. Negative-staining TEM image of the GPT NPs. Fig. S2. Fourier Transform Infrared (FTIR) spectroscopy of the GPT NPs. Fig. S3. Fluorescence spectroscopy of GPT NPs. Fig. S4. The free Gd3+ leakage from GPT NPs and Omniscan. Fig. S5. Blood circulation curve of GPT NPs. Fig. S6. The free Gd3+ leakage from GPT NPs. Fig. S7. T1-weighted MRA images of PANC-1 tumor-bearing mice before and after intravenous GPT NPs and Omniscan. Fig. S8. T1-weighted MRI-signal intensities of tumor site after the intravenous administration of GPT NPs and Omniscan. Fig. S9. Relative viabilities of PDEC cells and PANC-1 cancer cells after incubation with GPT NPs. Fig. S10. Relative viabilities of PDEC cells and PANC-1 cancer cells after incubation with Omniscan. Fig. S11. Time-dependent body-weight changing profiles of BALB/c mice after intravenous administration of GPT NPs. Fig. S12. Liver function indexes of BALB/c mice after intravenous injection of GPT NPs. Fig. S13. Kidney function indexes of BALB/c mice after intravenous injection of GPT NPs. Fig. S14. Hematological white blood cells analyses of BALB/c mice after intravenous injection of GPT NPs. Fig. S15. Hematological platelets analyses of BALB/c mice after intravenous injection of GPT NPs. Fig. S16–S17. Hematological hemoglobin and red blood cells analyses of BALB/c mice after intravenous injection of GPT NPs. Fig. S18. H&E-stained tissues sections from BALB/c mice of BALB/c mice after intravenous injection of GPT NPs.

BackgroundTakayasu’s arteritis (TA) is a type of primary large vessel vasculitis. Th1, Th17, and Tfh cells have been reported to be associated with TA relapse. However, the relationship between regulatory T cells (Tregs) and TA remains unclear.ObjectiveTo analyze the levels of circulating lymphocytes, especially Treg cells (CD4+CD25+FOXP3+ T cells) and serum cytokines in TA patients and explore their relationship with their changes and TA disease activity.MethodsA total of 57 TA patients and 43 sex- and age-matched healthy controls (HCs) were enrolled. According to NIH standards, 36 patients had active disease status. Flow cytometry combined with counting was used to detect the absolute numbers and ratios of Th1, Th2, Th17, and Treg cells in the peripheral blood of all the subjects. Magnetic bead-based multiplex immunoassay was used to detect cytokines.ResultsCompared to HCs, the absolute number and proportion of peripheral Treg cells in TA patients was significantly decreased, while Th17 cells were significantly increased. Furthermore, compared to the inactive group, the TA active group had significantly increased levels of interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α, but lower IL-10 levels. The absolute number of Th2 cells was negatively associated with platelet (PLT) and NIS scores in TA patients. The proportion of Th2 cells was negatively associated with the erythrocyte sedimentation rate in TA patients. After treatment, Treg cells were markedly increased.ConclusionThere was a Th17-Treg cell imbalance with a significant reduction in peripheral Treg cells and an increase in Th17 cells in TA patients compared to the HCs. The levels of IL-6, IL-10, IL-17, and TNF-α appeared to be related to disease activity.