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Aromatic polyimide films are widely used in high-tech fields due to their excellent combination of thermal, mechanical, and electrical properties. These films serve as precursors for the preparation of high thermal conductivity graphite films, with carbon content up to 70%, exhibits exceptional thermal and electrical conductivity, making it a promising precursor for polymer-based graphite films. This study focuses on the reserch of graphitization using commercial DuPont Kapton polyimide film. The polyimide film was rapped around a cylindrical mold and heat-treated at various temperatures. The impact of the process system on graphitization was thoroughly investigated, along with the evolution of polyimide's structure and properties during heat treatment. Results demonstrated that the size of the prepared films initially increased and then decreased with the increase in graphitization temperature. Additionally, the color of the prepared films transitioned from yellow-brown to black and eventually gray matte. The brittleness of the prepared films followed a similar pattern of initially increasing and then decreasing. When the temperature was below 2200 °C, the surface of the graphite films was smooth and defectless. However, at 2200 °C, small holes appeared on the surface, and at 2300 °C, the surface began to exhibit a "foaming" phenomenon, which intensified with temperature. XRD and Raman spectra analysis revealed that the degree of graphitization, crystallinity, and order of the prepared films increased with temperature. At 2800 °C, the sample achieved a theoretical degree of graphitization of 95.35% and a thermal conductivity of 1246.36 W/(m·K). [ABSTRACT FROM AUTHOR]

The article investigates the effectiveness and safety of interleukin-17 inhibitors (IL-17i) in treating erythrodermic psoriasis, comparing these biologics to conventional therapies. Topics include the significant improvement in Psoriasis Area and Severity Index (PASI) scores with IL-17i, better control of edema, and improved quality of life measures compared to conventional treatments.

Objectives: The study aims to evaluate the incremental predictive value of pericarotid fat density (PFD) on head and neck computed tomography angiography (CTA) for the obstructive coronary artery disease (CAD) (≥ 50% stenosis) relative to a clinical risk model (Framingham risk score (FRS)) and the degree of carotid artery stenosis and plaque type in acute ischemic stroke (AIS) or transient ischemic attack (TIA) patients without a known history of CAD. Methods: In a cohort of 134 consecutive stable patients diagnosed with AIS or TIA undergoing head and neck CTA between January 2010 and December 2021, pericarotid adipose tissue density (PFD) was quantified using a dedicated software. We collected demographic and clinical data, assessed the risk of CAD using the FRS, and analyzed coronary and carotid artery CTA images. Univariate and multivariate logistic regression analyses were performed to assess associations between FRS, PFD, CTA variables, and obstructive CAD risk. Four prediction models were established to evaluate the incremental predictive value of PFD relative to FRS, stenosis degree, and plaque types. Receiver operating characteristic (ROC) curves were generated, and the areas under the curves (AUC) were compared. Results: Increasing FRS, stenosis degree, and PFD values were positively correlated with obstructive CAD (all p < 0.05). In the predictive models for obstructive CAD, the model incorporating carotid stenosis exhibited superior predictive performance compared to FRS alone (p < 0.05). Moreover, the predictive model integrating PFD demonstrated enhanced performance and yielded the highest AUC of the receiver operator characteristic curve (AUC = 0.783), with sensitivity and specificity values of 86.89% and 65.75%, respectively. Conclusion: CTA-derived PFD measurements offer supplementary predictive value for obstructive CAD beyond FRS and stenosis, thereby facilitating improved risk stratification of TIA or stroke patients without a history of CAD history. Clinical relevance statement: CTA-derived PFD provides incremental predictive value for obstructive coronary artery disease in acute ischemic stroke or transient ischemic attack patients without CAD history, beyond Framingham risk score and carotid artery stenosis degree, improving risk stratification. Key Points: • Pericarotid fat density is associated with obstructive coronary artery disease in acute ischemic stroke or transient ischemic attack patients. • Higher pericarotid fat density corresponds to an increased risk of obstructive coronary artery disease. • Estimation of pericarotid fat density using computed tomography angiography imparts additional predictive value for obstructive CAD in risk stratification of acute ischemic stroke or transient ischemic attack patients. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the diagnostic accuracy of liver dual-layer spectral-detector CT (SDCT) derived parameters of liver parenchyma for grading steatosis with reference to magnetic resonance imaging-based proton density fat fraction (MRI-PDFF). Methods: Altogether, 320 consecutive subjects who underwent MRI-PDFF and liver SDCT examinations were recruited and prospectively enrolled from four Chinese hospital centers. Participants were classified into normal (n = 152), mild steatosis (n = 110), and moderate/severe(mod/sev) steatosis (n = 58) groups based on MRI-PDFF. SDCT liver parameters were evaluated using conventional polychromatic CT images (CTpoly), virtual mono-energetic images at 40 keV (CT40kev), the slope of the spectral attenuation curve (λ), the effective atomic number (Zeff), and liver to spleen attenuation ratio (L/S ratio). Linearity between SDCT liver parameters and MRI-PDFF was examined using Spearman correlation. Cutoff values for SDCT liver parameters in determining steatosis grades were identified using the area under the receiver-operating characteristic curve analyses. Results: SDCT liver parameters demonstrated a strong correlation with PDFF, particularly Zeff (rs = −0.856; p < 0.001). Zeff achieved an area under the curve (AUC) of 0.930 for detecting the presence of steatosis with a sensitivity of 89.4%, a specificity of 82.4%, and an AUC of 0.983 for detecting mod/sev steatosis with a sensitivity of 93.1%, a specificity of 93.5%, the corresponding cutoff values were 7.12 and 6.94, respectively. Zeff also exhibited good diagnostic performance for liver steatosis grading in subgroups, independent of body mass index. Conclusion: SDCT liver parameters, particularly Zeff, exhibit excellent diagnostic accuracy for grading steatosis. Critical relevance statement: Dual-layer SDCT parameter, Zeff, as a more convenient and accurate imaging biomarker may serve as an alternative indicator for MRI-based proton density fat fraction, exploring the stage and prognosis of liver steatosis, and even metabolic risk assessment. Key Points: Liver biopsy is the standard for grading liver steatosis, but is limited by its invasive nature. The diagnostic performance of liver steatosis using SDCT-Zeff outperforms conventional CT parameters. SDCT-Zeff accurately and noninvasively assessed the grade of liver steatosis. [ABSTRACT FROM AUTHOR]

Biochar application can alleviate the adverse effects of saline-alkali stress on crops. However, the long-term effects of one-off biochar application on soil physicochemical properties, salt concentration, nutrient availability, soil enzyme activities, and rice yield under highly saline-alkali paddy soils remain unclear. Here, a 6-year paddy field study was conducted in a saline-alkali paddy field using two nitrogen application levels (0 and 225 kg ha−1) and four biochar application rates [0 (T0), 1.5% (T1.5), 3.0% (T3.0), and 4.5% (T4.5) biochar, w/w]. The results showed that compared with T0, the bulk density (BD) under T1.5, T3.0, and T4.5 treatments significantly decreased by 11.21%, 16.33%, and 25.57%, while total porosity (Tp) and saturated hydraulic conductivity (Ks) increased by 19.15–27.34% and 3217.78–5539.83%, respectively. Biochar consistently improved soil macro-aggregates, mean weight diameter (MWD), and the percentage of water-stable aggregates (PWSA) over the years. Additionally, one-off application of biochar continuously reduced the soil Na+ concentration, Na+/K+ ratio, Na+/Ca2+ ratio, saturated paste extract (ECe), exchangeable sodium percentage (ESP), and sodium adsorption ratio (SARe). However, it reduced the pH in 2021 and 2022 only. It enhanced the concentration of K+, Ca2+, Mg2+, and cation exchange capacity (CEC) over the 6-year study, indicating its longer-term positive impact. Furthermore, the one-off biochar application, especially under high application rate treatments (T3.0 and T4.5), significantly and continuously improved nutrient availability and soil enzyme activities. However, alkali-hydrolysable nitrogen (AN) decreased in the initial year of biochar application. The grain yield of T1.5, T3.0, and T4.5 surpassed that of T0 by 116.38%, 141.24%, and 145.20%, respectively. Notably, the rice yield reached its peak with the treatment of 3.0% (w/w) in all 6 years of study period. These findings offered new perspectives on repairing and improving soil quality and production ability of highly saline-alkali paddy soils. Highlights: A long-term (6-year), one-off application of biochar was conducted in a highly saline-alkali paddy field. Biochar consistently decreased soil BD, increased Tp, Ks, and improved soil aggregates. Biochar showed a sustained ability to alleviate saline-alkali stress. The continuous improvement of soil functions acted on the increase of rice yield. [ABSTRACT FROM AUTHOR]