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Background: Hematoma expansion (HE) is common in patients with intracerebral hemorrhage (ICH) and associated with a worse outcome. Imaging makers and shorter time from symptom onset are both associated with HE, but prognostic scores based on these parameters individually have not been satisfactory. We hypothesized that a score including both imaging markers of expansion, and time of onset, would improve prediction. Methods: Patients with supratentorial ICH within 6 h after onset were consecutively recruited from six centers between January 2018 and August 2022. Three markers were used: hypodensities, the blend sign, and the island sign. We first defined frequency of imaging markers (FIM) as the relationship between the number of imaging markers and onset-to-CT time (OCT). The time-adjusted FIM was defined as the ratio of the number of imaging markers to the onset-to-initial imaging time. Multivariate analysis was performed to determine the relationship between FIM and HE. Receiver operating curve analysis was used to identify potential threshold values of FIM that optimally predict HE. In addition, the sensitivity, specificity, positive and negative predictive values (PPVs and NPVs), and the area under the curve (AUC) of the optimal cut-off in predicting HE were calculated. Results: In total, 1488 patients were eligible for inclusion, of whom 418 had incident HE. Multivariate analysis showed that age, male sex, baseline Glasgow Coma Scale score, presence of intraventricular hemorrhage, and FIM were independent predictors of HE (odds ratio (OR) = 0.98, 95% confidence interval (CI) = 0.97–0.99; OR = 1.73, 95% CI = 1.28–2.35; OR = 0.87, 95% CI = 0.83–0.92; OR = 0.42, 95% CI = 0.28–0.62; OR = 7.82, 95% CI = 5.86–10.42, respectively). The optimal cut-off point for FIM in predicting HE was 0.63, with sensitivity, specificity, PPV, NPV, and AUC values of 0.69, 0.89, 0.71, 0.88, and 0.83, respectively. Conclusion: The FIM adjusted for time since symptom onset is a significant predictor of HE. Its use may allow improved prediction of those patients with ICH who develop HE, and the score may be clinically applicable in the management of patients with ICH. [ABSTRACT FROM AUTHOR]

Mechanical performance is crucial for biomedical applications of scaffolds. In this study, the stress distribution of six lattice-inspired structures was investigated using finite element simulations, and scaffolds with pre-designed structures were prepared using selective laser sintering (SLS) technology. The results showed that scaffolds with face-centered cubic (FCC) structures exhibited the highest compressive strength. Moreover, scaffolds composed of polylactic acid/anhydrous calcium hydrogen phosphate (PLA/DCPA) showed good mechanical properties and bioactivity. An in vitro study showed that these scaffolds promoted cell proliferation significantly and showed excellent osteogenic performance. Composite scaffolds with FCC structures are promising for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Inorganic insulating powder can potentially be used in nuclear power plant cables, fire-resistant cables, and so on due to its high heat resistance and radiation resistance. It is of great academic and engineering value to study the dielectric properties of inorganic insulating powder. In this paper, we aim to study the nonlinear dielectric properties via the measurement of the time-domain polarization current spectrum under the application of a DC electric field. Three kinds of silica powders are measured by a measurement system with adjustable pressure. The effects of powder shape, particle size, and packing pressure and temperature on the dependence of relaxation polarization and electrical conductivity on the applied electric field are studied. The experimental results show that the relationship between electrical conductivity and the electric field of inorganic insulating powder presents two different characteristics, i.e., field-induced enhancement and field-induced weakening. The relationship between conductance and temperature shows an increase with temperature. That is, the electrical conductivity increases or decreases with the increase in temperature. The inorganic powder insulation can be regarded as a composite, which is composed of inorganic powder particles and air gaps. The interface between the powder particles and air gaps contributes a lot to the polarization of inorganic insulating powder. The phenomena (including the field-induced weakening characteristic between relaxation polarization and electric field and the decrease characteristic of polarization with increasing temperature) can be explained by a simplified interface polarization mechanism. [ABSTRACT FROM AUTHOR]