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(Hf 1-x Zr x)B 2 solid solution powders were synthesized by two methods. First, solution-based processing of HfCl 4 , ZrCl 4 , sucrose, and H 3 BO 3 was conducted followed by heat treatment in Argon to carry out the carbothermal reduction (CTR) reaction to form the diboride powders. Alternatively, in the so-called borohydride reduction (BHR) method, HfCl 4 , ZrCl 4 and NaBH 4 were mixed in an Argon glove box followed by heat treatment in Argon at 700−1500 °C. The synthesized powders were characterized by XRD, SEM, TEM, EDS, and TGA, and the influence of different parameters such as starting composition, heat treatment temperature and time on products characteristics were revealed. Both CTR and BHR solid solution powders were then consolidated within ∼5 min in a homemade flash sintering (FS) setup. The composition, microstructure, hardness, and thermal-oxidation properties of flash sintered ceramics were characterized, and the implication of this study and directions for future research were discussed. [ABSTRACT FROM AUTHOR]

Objective: To exp lore changes in immunoglobulin (Ig) levels for people with relapsing-multiple sclerosis (RMS) treated with ocrelizumab or ofatumumab and the relationship between Ig levels and infections. Methods: A systematic literature review (SLR) was conducted to identify clinical trials and real-world evidence (RWE) studies on Ig levels over time and studies on associations with infections for ocrelizumab and ofatumumab for people with RMS through 10 September 2021. Searches were conducted in Embase, MEDLINE, Cochrane Library, trial registries, and recent conference abstracts. Results: Of 1,580 articles identified, 30 reporting on 11 trials and 5 RWE studies were included. Ocrelizumab trials (n = 4) had 24–336 weeks of follow-up and reported decreasing Ig G (IgG) levels, while RWE (n = 5) had 52–78 weeks of follow-up and reported IgG to be stable or decrease only slightly. IgG levels were stable in ofatumumab trials (n = 5; 104–168 weeks of follow-up), but no RWE or longer-term studies were identified. No apparent association between decreased Ig levels and infections was observed during ofatumumab treatment (ASCLEPIOS I/II), while for ocrelizumab, the only data on apparent associations between decreased IgG levels and serious infection rates were for a pooled population of people with RMS or primary progressive MS. Conclusion: Decreasing IgG levels have been correlated with increased infection risk over time. IgG levels appeared to decrease over time in ocrelizumab trials but remained relatively stable over time in ofatumumab trials. Additional research is needed to understand differences between ocrelizumab and ofatumumab and identify people at risk of decreasing IgG levels and infection. [ABSTRACT FROM AUTHOR]

In this research, near fully dense single phase bulk multicomponent transition metal nitride (Nb1/3Ta1/3Ti1/3)N1−δ has been successfully synthesized from mixed commercial powders of NbN, TaN and TiN via reaction flash sintering technique. This was performed with an applied pressure of ~ 35 MPa at 25°C under a constant DC electric field (~24‐32 V/cm). The flash event, which is the abrupt increase in current (up to ~ 25.2 A/mm2) and temperature, occurred without preheating. The threshold power dissipation on the sample right before the flash is ~ 0.7 W/mm3. The formation of single phase (Nb1/3Ta1/3Ti1/3)N1−δ random solid solution and its compositional uniformity were confirmed by XRD and EDS, respectively. The effects of ball milling duration and limiting current density on phase formation were studied. Simulation based on Joule heating provides an estimate of the ultimate sample temperature of ~ 1850°C. Vickers hardness of the obtained (Nb1/3Ta1/3Ti1/3)N1−δ is 17.6 ± 0.6 GPa, which is comparable to similarly flash sintered ingredient binary nitrides of TaN and NbN. TGA in air shows that the oxidation resistance of (Nb1/3Ta1/3Ti1/3)N1−δ is better than that of TaN and NbN but inferior to TiN. The study demonstrates that reaction flash sintering can be a highly efficient technique for synthesizing bulk multicomponent ceramics for both material fundamental investigations and application development. [ABSTRACT FROM AUTHOR]