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Background: Exsanguination can be fatal in patients with traumatic brain injury (TBI). We aimed to analyze and compare the prognostic performances of injury severity score (ISS), revised trauma score (RTS), shock index (SI), and modified early warning score (MEWS) for predicting massive transfusion (MT) in severe trauma patients with TBI., Methods: In this retrospective observational study, severe trauma patients with TBI who visited our emergency department between January 2018 and December 2020 were included in the study. TBI was considered when abbreviated injury scale was 3 or higher. The primary outcome was MT., Results: A total of 1108 patients were included, and MT was performed in 92 (8.3%) patients. Receiver operating characteristic analyses were performed to evaluate the accuracy of ISS, RTS, SI, and MEWS for predicting MT. The area under curves (AUCs) of ISS, SI, RTS, and MEWS for predicting MT were 0.725 (95% confidence interval [CI], 0.698-0.751), 0.676 (95% CI, 0.648-0.704), 0.769 (95% CI, 0.743-0.793), and 0.808 (95% CI, 0.784-0.831), respectively. The AUC of MEWS was significantly different from the AUCs of ISS and SI but not the AUC of RTS for predicting MT. In a multivariate analysis, Glasgow Coma Scale (odds ratio [OR], 0.856; 95% CI, 0.803-0.911), body temperature (OR, 0.596; 95% CI, 0.386-0.920), and fresh frozen plasma (OR, 2.031; 95% CI, 1.794-2.299) were independently associated with MT. MEWS (OR, 1.425; 95% CI, 1.256-1.618) was independently associated with MT after adjustment for confounders., Conclusion: MEWS may be a useful tool for predicting MT in severe trauma patients with TBI.

Self-assembled nano-layering resulting from combined ionic and hydrogen-bonding interactions of phosphate functional monomers with zirconia have been proposed. The purpose of this study was to investigate the bond strengths of two phosphate monomer-containing adhesive resin cements (Panavia F 2.0 and RelyX U200) to a conventional tetragonal zirconia (Lava Plus, LP) and a new cubic zirconia (Lava Esthetic, LE), with three different shade zones, after air-abrasion. The structures of the zirconia surfaces were examined with scanning electron microscopy (SEM) and X-ray diffractometry (XRD). Vickers hardness and fracture toughness of the surfaces were also evaluated using a hardness tester. After air-abrasion (with 50 µ m Al₂O₃ at a pressure of 0.25 MPa), the surface roughness was measured using confocal laser scanning microscopy (CLSM) and the resin cements were bonded (diameter: 2.38 mm) to the surfaces. All bonded specimens were stored in water at 37 °C for 24 h before performing the shear bond strength (SBS) test ( n = 15). In the SEM images, the LP group showed a finer grain size than the LE groups. The XRD patterns confirmed that LP and LE had tetragonal and cubic phases, respectively. Although there were no significant differences in Vickers hardness among the four groups ( p = 0.117), the three LE groups revealed inferior fracture toughness to the LP group ( p < 0.001). However, neither the surface roughness of the air-abraded zirconia surfaces nor SBS values of each resin cement bonded to them were significantly different ( p > 0.05). In conclusion, no significant difference in SBS value was detected between the tetragonal and cubic zirconia within each resin cement used, probably due to the similar surface roughness of the air-abraded zirconia ceramics.

In this study, the effect of graphene oxide nanosheets (GONs) embedded in a thin-film composite (TFC) polyamide (PA) membrane on the acid resistance of the membrane was investigated by comparison with the effect of oxidized single-walled carbon nanotubes (o-SWNTs). Both GONs and o-SWNTs increased the hydrophilicity of the membranes and caused the formation of ridges and clustered bumps on the surfaces, resulting in slightly improved water permeability. However, the o-SWNTs-embedded membrane did not show a difference in acid resistance depending on the concentration of embedded material, but the acid resistance of the GONs-embedded membrane increased with increasing concentration. The acid resistance of the GONs-embedded membranes appears to be mainly due to the barrier effect caused by the nanosheet shape of the GONs along with a sacrificial role of the PA layer protruded by the addition of GONs and the decrease of acid reaction sites by the hydrogen bonding between GONs and PA. When the TFC PA membrane was prepared with a high amount (300 ppm) of the GONs without considering aggregation of GONs, membrane selectivity exceeding 95% was maintained 4.7 times longer than the control TFC membrane. This study shows that the acid resistance can be enhanced by the use of GONs, which give a barrier effect to the membrane.

Membrane fouling remains a critical factor limiting the widespread use of membrane processes in water and wastewater treatment. To mitigate membrane fouling, we introduced a patterned morphology on the membrane surface using a lithographic method. A modified immersion precipitation method was developed to relieve the formation of dense layer at the solvent-nonsolvent interface, that is, the opposite side of the patterned surface. Diverse patterned membranes, such as pyramid-, prism-, and embossing-patterned membranes, were prepared and compared with a flat membrane in terms of morphology, permeability, and biofouling. Patterned membrane fidelity was largely dependent on the polymer concentration in cast solution. The patterned surface augmented the water flux in proportion to the roughness factor of the patterned membrane. However, the type of pattern did not affect substantially the mean pore size on the patterned surface. Deposition of microbial cells on the patterned membrane was significantly reduced compared to that on the flat membrane in the membrane bioreactor (MBR) for wastewater treatment. This was attributed to hydraulic resistance of the apex of the patterned surface, which induced local turbulence.