Analysis of Structural Heterogeneity in Low-Rank Coal and Its Pyrolyzed Char Using Multi-Point Scanning Micro-Raman Spectroscopy.

Understanding the changes in carbon structure during the mid-low-temperature pyrolysis of low-rank coal is important for efficient utilization. Raman spectroscopy is commonly used to analyze the structural order of carbonaceous materials, but traditional methods may overlook the heterogeneity of coal/char. This research explores the heterogeneity of char structure derived from low-rank coal at 700 °C through multi-point micro-Raman analysis. The analysis of parameters such as area (A), intensity (I), full width at half maximum (FWHM/W), and peak position (P) reveals that the carbon structure becomes less ordered as coal transforms into char due to the deposition of small molecules on the surface. The study emphasizes the benefits of multi-point detection for gaining in-depth insights into the structural evolution of carbonaceous materials. The increased standard deviation of Raman parameters indicates diverse structural characteristics resulting from pyrolysis at this temperature, which traditional methods may not capture effectively. The mapping method used in this research visually illustrates the distribution of carbon structures in the region.

Predicting cardiovascular risk stratification in apparently healthy population by using noninvasive ultrafast ultrasound imaging.

BACKGROUND: To investigate the association between cardiovascular risk estimated using the Framingham Risk Score (FRS) and carotid stiffening determined using ultrafast pulse wave velocity (ufPWV) measurements in apparently healthy individuals. METHODS: We enrolled 1034 apparently healthy participants without known cardiovascular disease who underwent ufPWV measurements. Clinical and laboratory findings, carotid intima-media thickness (cIMT), pulse wave velocity at the beginning of systole (PWV-BS), and pulse wave velocity at the end of systole (PWV-ES) were assessed. In FRS assessments based on major cardiovascular risk factors (CVRFs), participants were assigned into three risk categories: low risk (<10%, n = 679), intermediate risk (10-20%, n = 191), and high risk (>20%, n = 164); the low-risk category was further subdivided into three subcategories: < 1% (n = 58), 1%- 5% (n = 374) and > 5% (n = 247). Multivariate logistic regression analyses with crude and adjusted odds ratios (ORs) were used to evaluate the association of carotid stiffening and FRS-based risk stratification. RESULTS: Carotid stiffening indicated by PWV-BS and PWV-ES differed notably between the FRS-estimated low-risk vs. intermediate-risk and high-risk categories, but only PWV-ES differed notably among the low-risk subcategories (all p < 0.010), and correlated notably with the FRS-estimated risk most obviously in low-risk participants (r = 0.517). In participants with cIMT < 0.050 cm, only PWV-ES differed significantly among the FRS-estimated risk categories (all p < 0.001). Increased PWV-BS (adjusted OR: 1.49; p = 0.003) and PWV-ES (adjusted OR: 1.29; p = 0.007) were both associated with FRS categories independent of conventional CVRFs in low- vs. intermediate-risk categories, but not in low- vs. high-risk categories (all p > 0.050). CONCLUSION: In vivo imaging of carotid stiffening by ufPWV measurements is independently linked to FRS categories, and ufPWV indices may help stratify differing levels of cardiovascular risk in apparently healthy young people. AVAILABILITY OF DATA AND MATERIAL: Data generated or analyzed during the study are available from the corresponding author by reasonable request.

Carboxymethyl chitosan modification of cobalt-zinc bimetallic MOF for tetracycline hydrochloride removal: Exploration of the enhancement mechanism of the process.

This study synthesized a carboxymethyl chitosan-modified bimetallic Co/Zn-ZIF (CZ@CMC) with strong hydrophilicity and adsorption performance via the one-pot method. Tetracycline hydrochloride (TCH) was used as the model contaminant to evaluate the adsorption and peroxymonosulfate (PMS) activation properties of CZ@CMC. Mechanism showed that the adsorption behavior occurred through pore filling, electrostatic attraction, surface complexation, hydrogen bonding, and π-π stacking. In addition, a CZ@CMC/PMS system was constructed, which had excellent catalytic performance. The hydrophilicity and selective adsorption properties of CMC conferred a greatly accelerated CZ@CMC in catalyzing the PMS process with kobs of 0.095 min-1, in which OH, 1O2, SO4-, O2-, and Co(III) were the main ROS which quenching tests, EPR, and chemical probe experiments verified. In addition, the degradation pathways of TCH were obtained utilizing DFT and HPLC-MS and analyzed to show that the system possessed a good detoxification capacity. This work is expected to provide a green, efficient, and stable strategy to enhance the adsorption properties of catalytic materials and subsequently their co-catalytic properties.

Quantifying carotid stiffness in chronic kidney disease using ultrafast ultrasound imaging.

Background: The mortality and disability of chronic kidney disease (CKD) are highly linked to the incidence of atherosclerotic cardiovascular events. Numerous clinical biochemical indicators of renal function often only increase in advanced stages of CKD, driving an urgent need for reliable indicators of atherosclerosis in early CKD. Ultrafast pulse wave velocity (ufPWV) can evaluate the stiffness of the straight carotid in vivo and quantitatively reflect the degree of early atherosclerosis. However, the use of ufPWV in CKD has not yet been reported. In this study, we aimed to explore the association between carotid stiffness, quantified using ufPWV, and renal function in CKD patients. Methods: This cross-sectional study enrolled a total of 582 participants between March 2017 and May 2022 in the Affiliated Hospital of Nanjing University of Traditional Chinese Medicine. Among those, 205 individuals without a history of CKD and estimated glomerular filtration rate (eGFR) ≥90 mL/min/1.73 m2 were included as controls. According to the Kidney Disease Outcomes Quality Initiative (K/DOQI) expert group of the American Kidney Foundation staging for CKD, 44 stages 1 and 2 CKD patients were included in the early CKD group, whereas 49 stages 3, 4, and 5 CKD patients were included in the advanced CKD group. Clinical and serum parameters, ultrasonic characteristics including carotid intima-media thickness (cIMT), and pulse wave velocity at the beginning of systole (PWV-BS) and pulse wave velocity at the end of systole (PWV-ES) of systole were analyzed. One-way analysis of variance (ANOVA) and least significant difference (LSD) tests were performed to compare cIMT, PWV-BS, and PWV-ES among subgroups in pairs. Pearson's correlation analysis, scatter plots, and subgroups correlation analysis were used to determine the relationships among ultrasound characteristics (cIMT, PWV-BS, PWV-ES), and major cardiovascular risk factors. Results: PWV-BS and PWV-ES for the early and advanced CKD groups were significantly higher than those for controls (all P<0.05). PWV-ES had the greatest correlation with age (r=0.474, P<0.001). PWV-ES had the greatest increase with age in the early CKD group (r=0.698, P<0.001). Conclusions: ufPWV can be used for the quantitative evaluation of carotid stiffness in CKD patients. PWV-ES may be more advantageous in the assessment of carotid atherosclerosis in early CKD patients.

A modified Park's technique for creating a natural-looking double eyelid.

Objective: This study aimed to evaluate an improved park's technique to create a natural double eyelid and reduce scar formation. Methods: The levator aponeurosis, orbicularis oculi muscle, and dermis were fixed using subcutaneous intermittent sutures, and then the skin and the levator aponeurosis were sutured. Postoperative evaluation included double-eyelid stability, symmetry, double-eyelid curve, scar formation, and patient satisfaction. Results: Between January 2021 and August 2021, a total of 89 patients (178 eyes) underwent double-eyelid blepharoplasty by the same surgeon using this improved technique. The mean follow-up period was 15.5 months (range 10 to 18 months). Seventy-six patients were very satisfied with this surgical method, six patients were rather satisfied, and seven patients were dissatisfied. The overall satisfaction rate was 92.1%. Conclusion: This new blepharoplasty method generates a stable, natural double-eyelid line with minimal scarring.