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Concrete prepared using Gobi sand and gravel instead of ordinary sand and gravel is referred to as Gobi concrete. In order to explore the effect of fibers on the frost resistance of Gobi concrete, as well as to enhance the service life of Gobi aggregate concrete in Northwest China, experiments were conducted with fiber types (polypropylene fibers, basalt fibers, polypropylene–basalt fibers) and fiber volume fractions (0%, 0.1%, 0.2%, 0.3%) as variable parameters. This study investigated the surface morphology, mass loss rate, and relative dynamic elastic modulus of fiber-reinforced Gobi concrete after different freeze–thaw cycles (0, 25, 50, 75, 100). Corresponding frost damage deterioration models were proposed. The results indicate that fibers have a favorable effect on the anti-peeling performance, mass loss rate, and dynamic elastic modulus of Gobi aggregate concrete. The improvement levels of different fiber types are in the following order: 0.1% basalt-polypropylene fibers, 0.2% polypropylene fibers, and 0.3% basalt fibers. Compared to Gobi concrete exposed to natural environmental conditions, the freeze–thaw cycle numbers increased by 343, 79, and 69 times, respectively. A quadratic polynomial damage model for fiber-reinforced Gobi concrete, using relative dynamic elastic modulus as the damage variable, was established and demonstrated good predictive performance.

On account of the influence of the discontinuity of CRTS II ballastless track slabs and the discrete support of track pads on the high-speed rail vehicle-ballastless track system, a vibration analysis calculation model of the ballastless track-vehicle coupling system was established on the basis of the moving unit method. The dynamic response of the system at different travel speeds and with and without consideration of the track plate discontinuities was investigated. The effect of the random process discontinuity on the dynamic response of the steel rails was analyzed by Fourier inverse transform on the high and low discontinuity spectra of ballastless rails on China’s high-speed rail. We also generated time domain samples of the track discontinuity corresponding to the three percentile spectra. The results show that the dynamic response of the track structure increases with the speed of the train under the condition of track unevenness, with the dynamic response of the steel rail being the most significant, while the dynamic response of the track slab and concrete foundation decreases step by step compared with that of the steel rail; the discontinuity of the track slab has a low impact on the vertical acceleration of the vehicle and does not affect the smoothness of the train; the magnitude of the dynamic response of the rail increases as the amplitude of the irregularities increases or the wavelength decreases. In the wavelength of 2~30 m, the maximum and as the wavelength of the discontinuity sample increases, the oscillation of the power response time curve decreases significantly and tends to be smooth.

In this paper, the dynamic response of a simply supported beam subjected to a moving load is reinvestigated. Based on a new beam theory, slope inertia-based Timoshenko (SIBT), the governing equations of motion of the beam are derived. An analytical solution is presented by using a coupled Fourier and Laplace–Carson integral transformation method. The finite element solution is also developed and compared with the analytical solution. Then, a comparative study of three beam models based on the SIBT, Euler–Bernoulli and Timoshenko, subjected to a moving load, is presented. The results show that for slender beams, the dynamic responses calculated by the three theories have marginal differences. However, as the ratio of the cross-sectional size to beam length increases, the dynamic magnification factors for the mid-span displacement obtained by the SIBT and Timoshenko beams become larger than those obtained by the Euler–Bernoulli beams. Furthermore, until the ratio is greater than 1/3, the difference between the calculated results of the SIBT and Timoshenko beams becomes apparent.

As a primary load-bearing component, accurately predicting the bearing capacity of concrete-filled rectangular steel tube (CFRST) members is an essential prerequisite for ensuring structural safety. Machine learning methods are employed to model and predict the axial load bearing capacity of CFRST columns. A test database containing 1119 members is established, and the input parameters of the machine learning model are determined using a combination of data preprocessing and correlation analysis. Four machine learning algorithms, namely Lasso, ANN, RF, and XGBoost, are selected to build the prediction models for axial load bearing capacity, and a comparative analysis of their predictive performance is conducted. The feature importance analysis is performed using the SHAP method. The results indicate that the model based on the XGBoost algorithm achieves the highest prediction accuracy. Through comparison with six existing calculation methods in domestic and international codes, the reliability of its predictive performance is verified. [ABSTRACT FROM AUTHOR]

Spontaneous cerebrospinal fluid (CSF) rhinorrhea presenting as the sole symptom of untreated pituitary adenoma is rare, with only 15 cases having been reported in the English literature. All these untreated pituitary adenoma contributing to spontaneous CSF rhinorrhea were diagnosed by the preoperative neuroimaging. Herein, we described an extraordinary rare patient with a pituitary microadenoma, presenting with spontaneous CSF rhinorrhea as the sole symptom. However, this pituitary microadenoma was only found incidentally at surgery, not preoperatively. To the best knowledge of us, this is the first reported case of spontaneous CSF rhinorrhea associated with an untreated pituitary adenoma diagnosed at surgery. [ABSTRACT FROM AUTHOR]

To improve the energy dissipation capacity of rubber isolation bearings, it is important to find a new rubber material with good applicability and high damping properties. Two types of blends were prepared using nitrile rubber (NBR), brominated butyl rubber (BIIR) and ethylene-vinyl acetate copolymer (EVA): NBR/BIIR and NBR/BIIR/EVA. The vulcanization, mechanical and damping properties of the blends were analyzed. The results show that both blends exhibit excellent vulcanization plateaus and mechanical properties. For NBR/BIIR, as the BIIR content increases, the complementary effects of NBR and BIIR afforded by blending are enhanced. Two damping peaks appeared in the tanδ-T curve and shifted toward lower and higher temperatures, respectively, which clearly widened the effective damping temperature range. However, the damping value in the valley of the tanδ-T curve was as low as 0.39. For NBR/BIIR/EVA, the addition of EVA greatly increased damping in the valley of the tanδ-T curve to approximately 0.54. EVA was observed to be the optimal polymer for improving the compatibility of the NBR/BIIR blend. Moreover, hot air thermal aging tests showed that both blends demonstrated good stability.

Background: This meta‐analysis was conducted to investigate the diagnostic performance of P16INK4a gene promoter methylation as a biomarker of non‐small cell lung cancer (NSCLC). Methods: Two reviewers independently searched the Web of Science, PubMed, Cochrane, Embase, China National Knowledge Infrastructure, and Chinese Biomedical Literature databases. Publications relevant to P16INK4a gene promoter methylation in serum or bronchoalveolar fluid/sputum were screened and included in this meta‐analysis. Pooled diagnostic sensitivity, specificity, and symmetric receiver operating characteristic curve were calculated. Results: Twenty‐six publications with 1768 lung cancer cases and 1323 controls were included. The pooled sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio were 0.46 (95% confidence interval [CI] 0.43–0.48), 0.90 (95% CI 0.88–0.91), 6.33 (95% CI 3.89–10.30), 0.57 (95% CI 0.50–0.65) and 10.72 (95% CI 6.94–16.56), respectively, for P16INK4a gene promoter methylation as a biomarker for the diagnosis of NSCLC. The area under the symmetric receiver operating characteristic curve was 0.75 with a standard error of 0.004. No publication bias was detected via line regression test (t = 0.95; P = 0.35) and Begg's funnel plot. Conclusion: P16INK4a gene promoter methylation detection in serum or bronchoalveolar fluid/sputum may be a potential biomarker for NSCLC diagnosis; however, the sensitivity was relatively low, which is not suitable for NSCLC screening. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) a class of non-coding RNAs about 22 nt in size that are found in a wide range of organisms from plants, viruses to humans. MicroRNA has a wide range of biological functions. It can recruit related RNA enzymes and lead to mRNA degradation after binding to mRNA specificity, thus blocking the expression of protein encoding genes and then affecting their biological functions. In recent years, microRNA has been found to be closely related to the biological behaviors, such as the occurrence, development, invasion and metastasis of multiple human malignant carcinomas, and play a regulatory role in the above biological phenotypes. Lung cancer is the highest incidence of malignancy. The exact molecular mechanism of its occurrence and development has not been fully elucidated. Previous studies have shown that microRNA plays an important role in lung tumor suppressor gene inactivation, oncogene activation and epigenetics. At the same time, there are also reports that there is a significant difference in the expression of microRNA in patients with lung cancer and benign lung diseases. This differential expression provides a basis for the feasibility of microRNA as a diagnostic and pre biological marker for lung cancer.
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Background/aims: Esophageal carcinoma is one of the most aggressive human cancers, and novel treatment modality is required. Although expressing adequate levels of functional tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptors DR4/DR5, significant proportion of esophageal cancer cells exhibit resistance to the cytotoxic effect of this ligand. Licochalcone-A (LA), a flavonoid present in a variety of edible plants, exhibits a wide spectrum of pharmacologic properties such as anticancer, antioxidant, and anti-inflammatory activities., Methodology: Eca109 and TE1 cells were cultured and transfected, then their viability was detected using MTT assay. Immunoprecipitation and immunoblotting analysis and RT-PCR analysis were also performed., Results: In this study, we found that LA synergistically caused the TRAIL-induced apoptosis in Eca109 and TE1 cells. Such potentiation was achieved through inhibiting Akt activation and promoting proteasomal degradation of X-linked Inhibitor of Apoptosis Protein (XIAP) which mediated the survival signals and allow the cells to escape from apoptosis in various human cancers., Conclusions: The combination of TRAIL and LA might be a novel therapeutic strategy for esophageal carcinoma patients who fail to respond to standard chemotherapy.