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The perovskite structure oxide, CaMnO 3 , has been extensively investigated and applied as a potential microwave absorption material due to its versatile dielectric and spontaneous polarization. However, the low conductivity of pure CaMnO 3 material limits its further application. Herein, to increase dielectric loss and achieve better microwave absorption properties, lanthanum (La)-doped CaMnO 3 (Ca 1-x La x MnO 3) ceramics were fabricated by a high temperature solid state reaction. The results of XRD and XPS show that the La atom was efficiently doped at the Ca site in CaMnO 3 , which carries excess positive charges and affects the valence state of Mn ions and the concentration of oxygen vacancies. Therefore, the conductivity and imaginary permittivity of Ca 1-x La x MnO 3 ceramics increased dramatically with La-doped content. Benefiting from the tunable dielectric and impedance properties, Ca 1-x La x MnO 3 ceramics can be utilized in a highly efficient way to absorb microwave radiation with a thin thickness. The sample with x = 0.04 shows the best microwave absorption property, with an RL min value of -52.63 dB (d = 1.41 mm) and effective absorption bandwidth coves full X band in the thickness range from 1.315 mm to 1.395 mm. [ABSTRACT FROM AUTHOR]

Hydroformylation has been applied in the chemical industry for decades to produce n-aldehydes from 1-olefins and syngas (a mixture of CO and H 2). However, the difficulty of catalyst separation and harsh operating conditions of conventional homogeneous hydroformylation reactions have prompted researchers to explore heterogeneous catalytic strategies. In this work, a novel core-shell structured catalyst comprised of Rhodium nanoparticles (Rh NPs) homogeneously encapsulated in a silicalite-1 zeolite (Rh@S-1) is designed to realize a high activity in 1-hexene hydroformylation. The conversion of 1-hexene over the Rh@S-1 catalyst exhibits as high as 85.8%, and the ratio of n-heptanal to iso-heptanal reaches up to 2.5 at 90 °C. Multiple studies demonstrate that the outstanding catalytic activity over this core-shell structured catalyst can be explained by the highly active homogeneously dispersed Rh NPs and the distinguishable mass transfer effect of the unique and orderly micropores structure of silicalite-1 zeolite. Furthermore, by changing templating agent concentrations during the hydrothermal method, the size of the zeolite crystals can be easily controlled and is proven to be an essential factor affecting the hydroformylation performance. [Display omitted] • Design of core-shell structured Rh@S-1 catalyst by solvent-free hydrothermal method. • High reaction performance in hydroformylation of 1-hexene realized by Rh@S-1. • Synergistic effect of active Rh NPs and the shape selectivity of zeolite micropores. • Zeolite crystals size of Rh@S-1 affected the hydroformylation reaction activity. [ABSTRACT FROM AUTHOR]

Insulin resistance (IR) is the central pathophysiological feature in the pathogenesis of metabolic syndrome, obesity, type 2 diabetes mellitus (T2DM), hypertension, and dyslipidemia. As the main active ingredient in Lithocarpus litseifolius [Hance] Chun, previous studies have shown that phlorizin (PHZ) can reduce insulin resistance in the liver. However, the effect of phlorizin on attenuating hepatic insulin resistance has not been fully investigated, and whether this effect is related to AMPK remains unclear. The present study aimed to further investigate the effect of phlorizin on attenuating insulin resistance and the potential action mechanism. Free fatty acids (FFA) were used to induce insulin resistance in HepG2 cells. The effects of phlorizin and FFA on cell viability were detected by MTT analysis. Glucose consumption, glycogen synthesis, intracellular malondialdehyde (MDA), superoxide dismutase (SOD), total cholesterol (TC), and triglyceride (TG) contents were quantified after phlorizin treatment. Glucose uptake and reactive oxygen species (ROS) levels in HepG2 cells were assayed by flow cytometry. Potential targets and signaling pathways for attenuating insulin resistance by phlorizin were predicted by network pharmacological analysis. Moreover, the expression levels of proteins related to the AMPK/PI3K/AKT signaling pathway were detected by western blot. Insulin resistance was successfully induced in HepG2 cells by co-treatment of 1 mM sodium oleate (OA) and 0.5 mM sodium palmitate (PA) for 24 h. Treatment with phlorizin promoted glucose consumption, glucose uptake, and glycogen synthesis and inhibited gluconeogenesis in IR-HepG2 cells. In addition, phlorizin inhibited oxidative stress and lipid accumulation in IR-HepG2 cells. Network pharmacological analysis showed that AKT1 was the active target of phlorizin, and the PI3K/AKT signaling pathway may be the potential action mechanism of phlorizin. Furthermore, western blot results showed that phlorizin ameliorated FFA-induced insulin resistance by activating the AMPK/PI3K/AKT signaling pathway. Phlorizin inhibited oxidative stress and lipid accumulation in IR-HepG2 cells and ameliorated hepatic insulin resistance by activating the AMPK/PI3K/AKT signaling pathway. Our study proved that phlorizin played a role in alleviating hepatic insulin resistance by activating AMPK, which provided experimental evidence for the use of phlorizin as a potential drug to improve insulin resistance. [ABSTRACT FROM AUTHOR]

The seismic response is a critical aspect of structural engineering, as it directly influences the design and safety evaluation of such systems. Structural seismic response becomes more complicated when unavoidable uncertainties in the structure are considered. Therefore, solving and analyzing the stochastic dynamic response of structures efficiently and accurately is of great significance. Various uncertainty quantification methods such as the stochastic finite element method, Monte Carlo method, and polynomial chaos expansion method have made significant progress in this field. However, these methods do not provide a comprehensive study of the seismic response of stochastic structures and efficiency problems rapidly emerge as the number of random variables increases. This paper delivers a comprehensive study of the seismic dynamic response of space truss and reticulated shell structure considering uncertainties in material properties, geometry, and loading. To this end, the finite element model of the structure was first modeled and the deterministic solutions were obtained. Then, polynomial surrogates are modeled for the natural frequency, mode participation factor, mode superposition response, and transient response of the structure under stochastic uncertainties. The sparse grid technique is used to select sparse quadrature points, which overcomes the curse of dimensionality caused by full grid integration. The results demonstrate that the sparse grid-based polynomial chaos expansion is more efficient. Uncertainty quantification reveals the uncertainty of modal analysis, response spectrum analysis, and transient response analysis of space truss and reticulated shell under seismic excitation. In summary, this study provides valuable insights and an efficient and accurate uncertainty quantification tool for the seismic dynamic analysis of stochastic structures, ultimately contributing to safer and more robust structural designs. • Analyzing the seismic dynamic response of stochastic structures comprehensively. • Sparse grid-based PCE for quantifying uncertainty in stochastic dynamics. • Addressing the dimensional catastrophe of traditional non-intrusive PCE. • Sparse grid-based PCE metamodel for post-processing is more efficient and accurate. [ABSTRACT FROM AUTHOR]

Geniposidic acid (GPA) alleviates oxidative stress and inflammation in mice However, whether it can effectively regulate lipid accumulation and prevent hyperlipidemia requires further investigation. This study combined the untargeted metabolomics of cells and a Caenorhabditis elegans model to evaluate the anti-hyperlipidemic potential of GPA by modulating oxidative stress and regulating lipid metabolism. A golden hamster model of hyperlipidemia was used to further validate the lipid-lowering effect and mechanism of action of GPA. Chemical staining, immunofluorescence, and flow cytometry were performed to examine the effects of GPA on lipid accumulation and oxidative stress. Untargeted metabolomic analysis of cells and C. elegans was performed using ultra-performance liquid chromatography coupled with quadrupole electrostatic field Orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap MS) to identify biomarkers altered by GPA action, analyze the affected metabolic pathways, and validate the mechanisms by which GPA regulates lipid metabolism and oxidative stress. A golden hamster model of hyperlipidemia was established to test the lipid-lowering effects of GPA. Body weight, biochemical markers, rate-limiting enzymes, and key proteins were assessed. Hematoxylin and eosin (H&E) and Oil Red O staining were performed. Phenotypic data showed that GPA decreased free fatty acid (FFA)-induced lipid buildup and high reactive oxygen species (ROS) levels, reversed the decrease in mitochondrial membrane potential (MMP), and increased the cellular reduced glutathione/oxidized glutathione disulfide (GSH/GSSG) ratio. GPA also reduces high glucose-induced lipid build-up and ROS production in C. elegans. Metabolomic analysis showed that GPA affected purine, lipid, and amino acid metabolism. Moreover, GPA inhibited xanthine oxidase (XOD), glutamate dehydrogenase (GLDH), fatty acid synthase (FAS), phosphorylation of P38 MAPK, and upregulated the expression of SIRT3 and CPT1A protein production to control lipid metabolism and produce antioxidant benefits in cells and golden hamsters. Current evidence suggests that GPA can effectively regulate lipid metabolism and the oxidative stress response, and has the potential to prevent hyperlipidemia. This study also provided an effective method for evaluating the mechanism of action of GPA. [Display omitted] [ABSTRACT FROM AUTHOR]

The study aimed to evaluate the role of postoperative radiotherapy (PORT) in the treatment of trachea and main bronchus adenoid cystic carcinoma (ACC) with a positive surgical margin. Patients with pathologically confirmed trachea or main bronchus ACC operated on at Shanghai Chest Hospital were enrolled. Survival, univariate, and multivariate analyses were performed. The χ2 test was applied to analyze the failure patterns among different groups (R0/0: negative margin resection without PORT; R1/0: positive margin resection without PORT; R1/1: positive margin resection with PORT). From January 2001 to December 2014, 77 patients were deemed eligible for the study. Pairwise comparisons showed that the overall survival rate of group R1/1 was comparable to that of group R0/0 (P =.438), and significantly longer than the rate of group R1/0 (P =.032). Additionally, the local disease-free survival rate of group R1/1 was much higher than that of group R0/0 (P =.023) and R1/0 (P =.001). Cox multivariate analysis identified the radiologic feature (P =.012) and PORT (P =.006) as significantly favorable prognostic factors for locoregional disease-free survival. By contrast, for overall survival, PORT (P =.032) was the only corresponding variable identified by univariate analysis. Furthermore, PORT significantly decreased the locoregional recurrence rate (P =.002) but not distant metastases (P >.999). PORT helped patients with tracheobronchial ACC and microscopic positive surgical margins to achieve a similar outcome as patients with complete resection. R0 resection may not be necessary for tracheobronchial ACC if it is difficult to be completely resected. [ABSTRACT FROM AUTHOR]

Total lung-sparing tracheobronchial sleeve resections are a step forward in the treatment of low-grade bronchial tumors in which minimal resection margins are required to achieve complete control of the disease. This study retrospectively collected data on patients who underwent total lung-sparing procedures for low-grade tracheobronchial tumors at 2 thoracic surgical centers from January 1984 to October 2019. The study included 98 patients, 46 –female (47%) and 52 –male (53%), with a median age of 39 years (range, 7 to 70 years). Thirty-four patients underwent operative endoscopy before surgery (32 had laser treatment, and 2 had endobronchial stenting). The surgical resections were as follows: 9 (9%), tracheal carina; 18 (18%), second carina; 31 (32%), left main bronchi; 25 (26%), right main bronchi; and 15 (15%), intermediate bronchus. The median length of the resected bronchus was 2.2 cm. The median postoperative in-hospital stay was 8 days, and no perioperative mortality was observed. Postoperative complications were recorded in 26-patients (27%). The final histologic classification was as follows: 37 typical carcinoids (38%); 10 atypical carcinoids (10%); 29 adenoid cystic carcinomas (30%); 15 mucoepidermoid carcinomas (15%); 6 inflammatory myofibroblastic tumors (6%); and 1 glomic tumor (1%). Twenty-two patients had positive resection margins and underwent adjuvant radiotherapy. Three patients with adenoid cystic carcinoma had recurrences (1 local and 2 systemic). After a median follow-up time of 54.5 months (range, 4 to 360 months), the overall actuarial 5-year survival was 97%. Total lung-sparing tracheobronchial sleeve resection for low-grade malignant disease requires advanced surgical skills, but the hospital morbidity and mortality are very low. This technique is adequate and safe for highly selected patients with low-grade endobronchial malignant diseases, and its use should be encouraged in experienced centers. [ABSTRACT FROM AUTHOR]

Texture analysis is an emerging field that allows mathematical detection of changes in MRI signals that are not visible among image pixels. Alzheimer's disease, a progressive neurodegenerative disease, is the most common cause of dementia. Recently, multiple texture analysis studies in patients with Alzheimer's disease have been performed. This review summarizes the main contributors to Alzheimer's disease-associated cognitive decline, presents a brief overview of texture analysis, followed by review of various MR imaging texture analysis applications in Alzheimer's disease. We also discuss the current challenges for widespread clinical utilization. MR texture analysis could potentially be applied to develop neuroimaging biomarkers for use in Alzheimer's disease clinical trials and diagnosis. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the value of magnetic resonance (MR) quantitative analysis (MR-T2 mapping technique) for the evaluation of eccentric exercise-induced skeletal muscle injury.Materials and Methods: We established an animal model of eccentric exercise-induced damage of Sprague Dawley rat skeletal muscle and evaluated the animals by MR imaging, determined the serum levels of fast skeletal troponin (fsTnI), and examined muscle histopathology, at 0, 1, 2, 4, and 7 days after eccentric exercise. The associations between MR imaging findings, and histopathological and laboratory results were evaluated.Results: T2-weighted images (WIs) of quadriceps femoris muscles showed obvious high signal intensities after exercise, and the T2 values and serum fsTnI levels continued to increase, peaking at day 2 after exercise, p< 0.05. The histopathological findings in muscle specimens, which included swollen and ruptured cells, enlarged extracellular spaces, inflammation, and regeneration of muscle fibers, showed similar trends. After day 2, muscle specimens began to show evidence of self-repair, the T2WI signals decreased in intensity, and the T2 values and serum fsTnI levels decreased; however, at day 7 post injury, the values remained slightly higher than those in the control animals, p< 0.05. The T2 value was significantly correlated with the serum fsTnI level (r = 0.896, p< 0.01).Conclusion: T2 mapping technology accurately reflects the histopathological and fsTnI abnormalities and the degree of skeletal muscle damage associated with eccentric exercise followed by recovery. Because T2 mapping technology is noninvasive and can be quantitatively analyzed, it might become the preferred method for performing the diagnosis of eccentric exercise-induced skeletal muscle injury. [ABSTRACT FROM AUTHOR]