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PURPOSE:To evaluate the relationship between the burden of chronic thromboembolic disease quantified via CT pulmonary angiography and pre-operative hemodynamics and post-operative hemodynamic improvement in CTEPH patients undergoing PTE. METHODS:CTEPH patients who underwent pulmonary thromboendarterectomy surgery (PTE) between December 2017 and August 2019 were retrospectively screened for having 1) preoperative CT pulmonary angiogram (CTPAs) with corresponding preoperative vascular annotations, 2) preoperative right heart catheterization, 3) bilateral level 2 surgical disease (defined from surgically resected thromboembolic specimen) and 4) recorded postoperative hemodynamics. Clot burden was quantified in preoperative CTPAs using the Qanadli score, which weights the location and severity of thromboembolic lesions into a per-patient score. Mean pulmonary artery pressure, pulmonary vascular resistance, and total pulmonary resistance were obtained from right heart catheterization preoperatively and then on the day of Swan-Ganz removal in the ICU postoperatively. Linear regression was performed between measured clot burden and hemodynamic variables. Continuous variables are presented as mean ± standard deviation. RESULTS:15 patients (7 females, age: 36 ± 13 years, BMI: 35.0 ± 6.7, preoperative mPAP: 40 ± 13 mmHg) met all inclusion criteria. Clot burden score ranged from 11 to 30, with a mean of 19 ± 6. Level of surgical disease seen on imaging matched surgical findings in 87% and 67% of cases (right and left lungs, respectively). Figure 1 illustrates the significant linear correlations between clot burden and preoperative mPAP (R2= 0.59), PVR (R2 = 0.69) and TPR (R2= 0.58), as well as post PTE improvement in PVR (R2 = 0.48) and TPR (R2 = 0.35). CONCLUSION:Pre-operative CT-based quantitative assessment of the pulmonary vasculature is associated with the hemodynamic severity of CTEPH and surgical improvement in PVR after PTE.

A ferrimagnetic hexagonal Ising nanotube with spin-1/2 core and spin-5/2 shell is investigated using the mean field approximation (MFA) and the Monte Carlo simulation (MCS). More exactly, we have examined the effects of the exchange interactions and crystal field on the magnetic properties of the system. Our phase diagrams show the appearance of critical and compensation behaviors, as well as first-order phase transitions terminating at isolated critical end-points in the ferrimagnetic phase region at low temperatures. Furthermore, we have made a comparison with other studies of similar nanosystems. [ABSTRACT FROM AUTHOR]

Mg2+ and Cu2+ codoped TiO2 nanostructures (Mg/Cu–Ti) were synthesized using the co-precipitation process and were annealed in air for two hours. We tried in this work to investigate how annealing temperature affects physical, morphological, optical, and photocatalytic properties. With increasing annealing temperature, X-ray diffraction (XRD) studies revealed that Mg/Cu–Ti nanostructures maintain the anatase hexagonal crystal structure (space group I41/amd). The average crystallite size grows with higher annealing temperatures, and the sample's morphology becomes more porous. Based on the Kubelka–Munk equation, the band gap widens as the temperature rises. The photocatalytic activity of the nanoparticles was assessed through the photodegradation of MB dye. It was found that annealing notably enhances the photodegradation efficiency. The experimental results showed that changing the annealing temperature might significantly alter the characteristic of Mg/Cu co-doped Mg/Cu–Ti nanostructures. [ABSTRACT FROM AUTHOR]

We investigated a three-dimensional semi-infinite spin-1/2 system bounded by a spin-1 surface using a Monte Carlo simulation based on the Metropolis algorithm. The exchange interactions and crystal field effects on phase diagrams, magnetizations, and susceptibilities were investigated. The phase diagrams in three planes were presented due to the competition between specific system parameters. The system demonstrated ordinary, extraordinary, surface, and special second-order phase transitions, as well as a surface first-order phase transition. Furthermore, tricritical and critical end-points were discovered. [ABSTRACT FROM AUTHOR]