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•Transverse and longitudinal flexural performances of STS composite slabs are presented.•Influences of the parameters on the flexural stiffness and capacity are examined.•A design ...formula is proposed to predict the elastic capacity.
The steel tube slab (STS) structure is a novel pipe-roofing structure, which is used as the support system for underground stations. The pipe-roofing structure is generally assumed as a beam structure in previous research, which is questionable, because the transverse and longitudinal coupling force mechanism is ignored. Hence, this work aims to investigate the flexural performance of STS composite slab through experimental test and establish a design approach for STS structure. Firstly, based on six tests on flexural performance of the STS composite slabs, the crack development, failure mode and deformation mechanism were analysed. Each of the specimens demonstrated a high bearing capacity that exceeded 3000 kN. Furthermore, the specimens exhibited ductility during testing with the failure occurring at either the flange or concrete between the steel tubes. Subsequently, the effect of the length–width ratio and spacing between the tubes on the flexural performance of the tested specimens were examined. The result indicated that the length–width ratio and the spacing between the tubes significantly affected the flexural stiffness, but had limited effects on the flexural capacity. Finally, a design approach was proposed to estimate the elastic capacity of STS composite slabs, and finite element (FE) models validated by the test results were established to increase the general applicability of the theoretical model. The predicted outcomes demonstrated a satisfactory correlation with both the test and FE results, with an average relative error of 9.8%. The study's findings are anticipated to serve as a dependable resource for the design and application of STS structures.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
It is widely believed that the quality and characteristics of Chinese strong-flavor liquor (CSFL) are closely related to the age of the pit mud; CSFL produced from older pit mud tastes better. This ...study aimed to investigate the alteration and interaction of prokaryotic communities across an age gradient in pit mud. Prokaryotic microbes in different-aged pit mud (1, 6, and 10 years old) were analyzed by Illumina MiSeq sequencing of the 16S rRNA gene. Analysis of the 16S rRNA gene indicated that the prokaryotic community was significantly altered with pit mud age. There was a significant increase in the genera Methanosarcina, Methanobacterium, and Aminobacterium with increased age of pit mud, while the genus Lactobacillus showed a significant decreasing trend. Network analysis demonstrated that both synergetic co-occurrence and niche competition were dominated by 68 prokaryotic genera. These genera formed 10 hubs of co-occurrence patterns, mainly under the phyla Firmicutes, Euryarchaeota, and Bacteroidetes, playing important roles on ecosystem stability of the pit mud. Environmental variables (pH, NH
4
+
, available P, available K, and Ca
2+
) correlated significantly with prokaryotic community assembly. The interaction of prokaryotic communities in the pit mud ecosystem and the relationship among prokaryotic communities and environmental factors contribute to the higher quality of the pit mud in older fermentation pits.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
p53 is the most commonly mutated tumor suppressor gene in human cancers. In addition to the loss of tumor suppression function and exertion of dominant-negative effects over the remaining wild-type ...protein, several p53 mutants can gain novel oncogenic functions (gain-of-function, GOF) that actively regulate cancer development and progression. In human endometrial cancer, p53 mutation is more often associated with aggressive nonendometrioid cancer. However, it was unknown if p53 mutants contributed to endometrial cancer progression through the GOF properties.
To clarify the relationship between expression of p53 GOF mutation (p53-R175H) and invasive potential of human endometrial cancer KLE cells, we tested the consequences of up-regulation and down-regulation of p53-R175H in KLE cells by inducing p53-R175H expression vector or suppressing the p53 gene with short hairpin RNA.
We found that forced over-expression of p53-R175H significantly promoted cell migration and invasion, and induced activation of the epidermal growth factor receptor (EGFR)/phosphatidylinositol 3-kinase (PI3K)/AKT pathway. Conversely, suppression of p53-R175H with short hairpin RNA significantly inhibited cell migration and invasion, and resulted in attenuation of EGFR/PI3K/AKT pathway.
These findings show for the first time that elevated expression of p53-R175H mutant may exert gain-of-function activity to activate the EGFR/PI3K/AKT pathway and thus may contribute to the invasive phenotype in endometrial cancer.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this work, MoS2-based hybrid tubular nanostructures are facilely synthesized via a self-assembly-assisted process and evaluated as a bifunctional electrocatalyst for hydrogen evolution reactions ...(HERs) and oxygen reduction reactions (ORRs). By simply mixing the reactants under ambient conditions, (NH4)2MoS4/polydopamine (PDA) hybrid nanospheres are formed. The protonated dopamine is linked to tetrahedral MoS42– via weak N–H···S and O–H···S interactions, causing the PDA nanospheres merging together and forming nanorods under stirring-induced shear force. Moreover, the oxidative polymerization of dopamine proceeds on the surface of the nanorods, whereas it is prohibited inside the nanorods owing to lack of oxygen, leading to outward diffusion of dopamine and hence cavitation. After annealing, the tubular morphology is perfectly retained, while ultrafine MoS2 monolayers are formed due to the confinement of the framework. Benefiting from these unique structural features, the MoS2/C hybrid nanotubes possess abundant active sites and high surface area, as well as boost electronic and ionic transport, remarkably enhancing their electrocatalytic activities. The onset and half-wave potentials are 0.91 and 0.82 V, respectively, for ORR, close to those of Pt/C. Moreover, low onset potential and small Tafel slope are also observed for HER, demonstrating the potential of the hybrid nanotubes as a promising non-noble metal bifunctional electrocatalyst.
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IJS, KILJ, NUK, PNG, UL, UM
The gamma-glutamyl transpeptidase to platelet ratio (GPR) is a novel index to estimate liver fibrosis in chronic hepatitis B (CHB). Few studies compared diagnostic accuracy of GPR with other ...non-invasive fibrosis tests based on blood parameters. We analyzed diagnostic values of GPR for detecting liver fibrosis and compared diagnostic performances of GPR with APRI (aspartate aminotransferase-to-platelet ratio index), FIB-4 (fibrosis index based on the four factors), NLR (neutrophil-to-lymphocyte ratio), AAR (aspartate aminotransferase/alanine aminotransferase ratio) and RPR (red cell distribution width-to-platelet ratio) in HBeAg positive CHB and HBeAg negative CHB. We found AUROCs of GPR in predicting significant liver fibrosis, advanced liver fibrosis and liver cirrhosis were 0.732 (95% CI 0.663 to 0.801), 0.788 (95% CI 0.729 to 0.847) and 0.753 (95% CI 0.692 to 0.814), respectively. Further comparisons showed the diagnostic performance of GPR was not significantly different with APRI, FIB-4 and RPR in identifying significant fibrosis, advanced fibrosis and cirrhosis, but it was significantly superior to AAR and NLR in both HBeAg positive CHB and HBeAg negative CHB. In conclusion, GPR does not show advantages than APRI, FIB-4 and RPR in identifying significant liver fibrosis, advanced liver fibrosis and liver cirrhosis in both HBeAg positive CHB and HBeAg negative CHB in China.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In this study, the effect of quercetin-3-O-β-D-glucuronide (Q3G) on the formation of fructosamine and 5-hydroxymethylfurfural (5-HMF), the amount of free amino groups and browning degree in a ...non-enzymatic glycosylation model consisting of bovine α-lactalbumin (α-La) and fructose were evaluated. In addition, the inhibitory mechanism of Q3G against non-enzymatic glycosylation was explored by molecular docking and mass spectrometry (MS). The results indicated that Q3G could significantly reduce the browning degree, increase the free amino groups, inhibit the formation of fructosamine and 5-HMF, and delay the process of glycosylation reaction. The effect was most pronounced at 2 mmol/L Q3G. Molecular docking analysis indicated that Q3G could bind with the active amino acid residues of α-La through hydrogen bonds, van der Waals force and hydrophobic interactions, delaying the process of glycosylation reaction. Meanwhile, by ultra-high performance liquid chromatography-quadrupole-orbitrap tandem mass spectrometry (UPLC-Q-Orbitrap MS/MS) analysis, it was found that Q3G shielded the potential glycosylation sites Lys93 and Lys108, and the activity of the glycosylation site Lys98 was weak, indicating inhibited non-enzymatic glycosylation reaction. This study can provide a theoretical basis for the development of Q3G as a potential anti-glycosylation agent.
Background
Myocardial injury has been found using magnetic resonance imaging in recovered coronavirus disease 2019 (COVID‐19) patients unselected or with ongoing cardiac symptoms.
Purpose
To evaluate ...for the presence of myocardial involvement in recovered COVID‐19 patients without cardiovascular symptoms and abnormal serologic markers during hospitalization.
Study Type
Prospective.
Population
Twenty‐one recovered COVID‐19 patients and 20 healthy controls (HC).
Field Strength/Sequence
3.0 T, cine, T2‐weighted imaging, T1 mapping, and T2 mapping.
Assessment
Cardiac ventricular function includes end‐diastolic volume, end‐systolic volume, stroke volume, cardiac output, left ventricle (LV) mass, and ejection fraction (EF) of LV and right ventricle (RV), and segmental myocardial T1 and T2 values were measured.
Statistical Tests
Student's t‐test, univariate general linear model test, and chi‐square test were used for analyses between two groups. Ordinary one‐way analyses of variance or Kruskal–Wallis H test were used for analyses between three groups, followed by post‐hoc analyses.
Results
Fifteen (71.43%) COVID‐19 patients had abnormal magnetic resonance findings, including raised myocardial native T1 (5, 23.81%) and T2 values (10, 47.62%), decreased LVEF (1, 4.76%), and RVEF (2, 9.52%). The segmental myocardial T2 value of COVID‐19 patients (49.20 46.1, 54.6 msec) was significantly higher than HC (48.3 45.2, 51.7 msec) (P < 0.001), while the myocardial native T1 value showed no significant difference between COVID‐19 patients and HC. The myocardial T2 value of serious COVID‐19 patients (52.5 48.1, 57.1 msec) was significantly higher than unserious COVID‐19 patients (48.8 45.9, 53.8 msec) and HC (48.3 45.2, 51.7) (P < 0.001). COVID‐19 patients with abnormally elevated D‐dimer, C‐reactive protein, or lymphopenia showed higher myocardial T2 values than without (all P < 0.05).
Data Conclusion
Cardiac involvement was observed in recovered COVID‐19 patients with no preexisting cardiovascular disease, no cardiovascular symptoms, and elevated serologic markers of myocardial injury during the whole course of COVID‐19.
Level of Evidence
1
Technical Efficacy
Stage 5
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
PurposeAn accurate prediction of the deformation of retaining structures is critical for ensuring the stability and safety of braced deep excavations, while the high nonlinear and complex nature of ...the deformation makes the prediction challenging. This paper proposes an explainable boosted combining global and local feature multivariate regression (EB-GLFMR) model with high accuracy, robustness and interpretability to predict the deformation of retaining structures during braced deep excavations.Design/methodology/approachDuring the model development, the time series of deformation data is decomposed using a locally weighted scatterplot smoothing technique into trend and residual terms. The trend terms are analyzed through multiple adaptive spline regressions. The residual terms are reconstructed in phase space to extract both global and local features, which are then fed into a gradient-boosting model for prediction.FindingsThe proposed model outperforms other established approaches in terms of accuracy and robustness, as demonstrated through analyzing two cases of braced deep excavations.Research limitations/implicationsThe model is designed for the prediction of the deformation of deep excavations with stepped, chaotic and fluctuating features. Further research needs to be conducted to expand the model applicability to other time series deformation data.Practical implicationsThe model provides an efficient, robust and transparent approach to predict deformation during braced deep excavations. It serves as an effective decision support tool for engineers to ensure the stability and safety of deep excavations.Originality/valueThe model captures the global and local features of time series deformation of retaining structures and provides explicit expressions and feature importance for deformation trends and residuals, making it an efficient and transparent approach for deformation prediction.
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging epidemic infectious disease caused by the SFTS bunyavirus (SFTSV) with an estimated high case-fatality rate of 12.7% to 32.6%. ...Currently, the disease has been reported in mainland China, Japan, Korea, and the United States. At present, there is no specific antiviral therapy for SFTSV infection. Considering the higher mortality rate and rapid clinical progress of SFTS, supporting the appropriate treatment in time to SFTS patients is critical. Therefore, it is very important for clinicians to predict these SFTS cases who are more likely to have a poor prognosis or even more likely to decease. In the present study, we established a simple and feasible model for assessing the severity and predicting the prognosis of SFTS patients with high sensitivity and specificity. This model may aid the physicians to immediately initiate prompt treatment to block the rapid development of the illness and reduce the fatality of SFTS patients.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Mg3(VO4)2 (MVO) microwave dielectric ceramics were fabricated by a conventional solid-state sintering method at different sintering temperatures (Ts) between 1000 °C and 1100 °C. The effects of Ts on ...the phase evolution, the crystal structures, the dielectric responses, and the lattice vibrational characteristics of MVO were investigated. XRD patterns after Rietveld refinement were applied to analyze the phase evolution and the crystal structures of the samples, which shows the orthorhombic structure with the space group of Cmca for the MVO ceramics. Micrograph from scanning electron microscopy shows a uniform and dense crystal structure with the highest bulk density for the MVO sample sintered at 1050 °C. Raman scattering spectroscopy and infrared reflectance spectroscopy were used to dissect the lattice vibrational characteristics of the MVO ceramics. There are two types of vibrational modes of the MVO samples, i.e., the external modes caused by the deformation of VO43- and the rotational and translational vibrations of the lattices, the internal modes attributed to the asymmetric stretching vibrations of V-O bonds. The intrinsic dielectric properties were determined by fitting the data with a four-parameter semi-quantum (FPSQ) model. Modes 1, 2, and 4, associated with the external modes, have the greatest contribution coefficient of 65.58% to the dielectric constant, and Mode 1 has the greatest contribution coefficient of 51.40% to the dielectric loss. The structure-property relationships were semi-quantitatively mathematically established according to the Raman modes. The MVO sample sintered at 1050 °C has the best dielectric properties of εr = 9.59 and Q × f = 41,193 GHz (f = 13.69 GHz).
•Mg3(VO4)2 microwave dielectric ceramics of crystal structures, dielectric properties, and phonon characteristics were studied.•The lattice vibrational characteristics were analyzed utilizing Raman and infrared reflection spectroscopy.•The physical mechanism of the dielectric response was clarified.•Relationships of structures-properties were established using Raman active modes as a media.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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