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Objective The Essen Stroke Risk Score (ESRS) is widely used to predict the risk of recurrent ischemic stroke but may not have sufficient discriminatory ability for predicting early recurrence. In this study, we developed a modified ESRS for predicting recurrent ischemic stroke at one year based on Chinese population. Methods Eight hundred and three consecutive patients were included in the study. We performed a univariate analysis to investigate the effect of previously identified risk factors on recurrent stroke at one year. The candidate predictors were included in a forward stepwise logistic regression model. Prediction scores were assigned based on β coefficient and a modified ESRS system was constructed. We used receiver operating characteristic (ROC) curves to compare the predictive ability of the modified and original ESRS. Results Recurrent ischemic stroke occurred in 85 (11.00%) patients and death occurred in 68 (8.80%) patients within one year. Hypertension over 15 years, diabetes over 10 years, large artery atherosclerosis cerebral infarction by TOAST criteria and a history of transient ischemic attack (TIA) or ischemic stroke (IS) were identified as independent risk factors for recurrent stroke (all P < 0.05). The areas under the ROC curves of ESRS and modified ESRS were 0.58 (P < 0.05, 95%CI: 0.51-0.64) and 0.70 (P < 0.05, 95% CI: 0.63-0.76), respectively. The modified ESRS appears to be superior to the original ESRS for predicting recurrent ischemic stroke at one year (P < 0.05). Conclusions The modified ESRS increased the ability of the original ESRS to predict recurrent stroke at one year among the Chinese population.

BackgroundPosterior canal-benign paroxysmal positional vertigo-cupulolithiasis (PC-BPPV-cu) is a new and controversial type of benign paroxysmal positional vertigo (BPPV). At present, there are few relevant clinical studies as to whether the Half Dix-Hallpike test (Half D-HT) induces more obvious nystagmus than the Dix Hallpike test (D-HT) and straight head hanging test (SHH) in patients with PC-BPPV-cu.ObjectivesTo investigate the clinical characteristics of PC-BPPV-cu, and analyze the diagnostic significance of the Dix-Hallpike test (D-HT), Half D-HT, and straight head hanging (SHH) test in these patients.MethodsA total of 46 patients with PC-BPPV-cu were enrolled, and divided into two groups (N = 23): a group A (induction order: D-HT, Half D-HT, SHH) and a group B (induction order: Half D-HT, D-HT, SHH).ResultsAmong 46 patients with PC-BPPV-cu, the bilateral and unilateral abnormality rates of the disease side were 5 cases and 41 cases, respectively. There were significant differences in the proportion of torsional-upbeating nystagmus and upbeating nystagmus among the three headhanging positions in 46 patients with PC-BPPV-cu (P &lt; 0.001). The slow phase velocity (SPV) of induced nystagmus at half D-HT supine position was slower than D-HT supine position (P &lt; 0.05) and SHH supine position (P &lt; 0.05). The nystagmus latency of D-HT supine position was significantly shorter than half D-HT (P &lt; 0.05) and SHH (P &lt; 0.05). PC-BPPV-cu patients were accompanied by 53.5% semicircular canal paresis, 69.6% audiological abnormalities, 76% cervical vestibular evoked myogenic potential (cVEMP), and 75% video head impulse test (vHIT) abnormalities, the concordance rates of the four detection methods were similar (χ2 = 0.243, P = 0.970).ConclusionsThe Half D-HT is simple and feasible, but might have a risk of false-negative diagnoses of the torsional-upbeating nystagmus and upbeating nystagmus. The D-HT is still a classic induction method for PC-BPPV-cu. The two complement each other and may aid in the diagnosis of PC-BPPV-cu patients. Future clinical applications of Half D-HT require extensive research to determine its diagnostic efficacy.

First-principles calculations were performed to investigate the effects of external pressure on the properties of intrinsic point defects in monoclinic zirconia. Our results show that when the applied external pressure increases from atmospheric pressure to 14.9 GPa, the formation energies of oxygen vacancies decrease with increasing pressure, while the formation energies of the cation and anion interstitials increase all over the pressure regime investigated. Among them the most remarkable change occurs in neutral zirconium interstitial with an increase of 2.21 eV. In particular, the formation energy of zirconium vacancy depends strongly on its charge state. For all the chemical potential and Fermi level considered, the cation and anion vacancies are the most stable defects in all cases. The present calculations also reveal that the formation energies of Frenkel defects could be raised by external pressures, while the energetics of Schottky defects are not much affected. Moreover, the charge state transition of defects is found to be greatly influenced by the external pressures, and thus the stability diagram of defects in ZrO2 is strongly dependent on external pressures. Our findings suggest that external pressures should raise the concentration of oxygen vacancies significantly.

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The unique flash heating characteristics of intense pulsed ion beams (IPIB) offer potential advantages to fabricate high-performance coatings with non-equilibrium structures. In this study, titanium-chromium (Ti-Cr) alloy coatings are prepared through magnetron sputtering and successive IPIB irradiation, and the feasibility of IPIB melt mixing (IPIBMM) for a film-substrate system is verified via finite elements analysis. The experimental results reveal that the melting depth is 1.15 μm under IPIB irradiation, which is in close agreement with the calculation value (1.18 μm). The film and substrate form a Ti-Cr alloy coating by IPIBMM. The coating has a continuous gradient composition distribution, metallurgically bonding on the Ti substrate via IPIBMM. Increasing the IPIB pulse number leads to more complete element mixing and the elimination of surface cracks and craters. Additionally, the IPIB irradiation induces the formation of supersaturated solid solutions, lattice transition, and preferred orientation change, contributing to an increase in hardness and a decrease in elastic modulus with continuous irradiation. Notably, the coating treated with 20 pulses demonstrates a remarkable hardness (4.8 GPa), more than twice that of pure Ti, and a lower elastic modulus (100.3 GPa), 20% less than that of pure Ti. The analysis of the load-displacement curves and H-E ratios indicates that the Ti-Cr alloy coated samples exhibit better plasticity and wear resistance compared to pure Ti. Specifically, the coating formed after 20 pulses exhibits exceptional wear resistance, as demonstrated by its H3/E2 value being 14 times higher than that of pure Ti. This development provides an efficient and eco-friendly method for designing robust-adhesion coatings with specific structures, which can be extended to various bi- or multi-element material systems.

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