Taking advantage of crumb rubber from waste tires to modify bitumen is widely for the environmentally friendly and sustainable development of pavement. This study investigated the modification ...mechanism, rheological, and aging properties of styrene–butadiene–styrene (SBS)/desulfurized crumb rubber (DCR) composite modified bitumen (SBS/DCRMB). Morphological features and chemical characteristics were assessed by fluorescence intensity measurement and gel permeation chromatography (GPC), respectively, and results demonstrated that the DCR and SBS modifier in SBS/DCRMB had been vulcanized and formed a three-dimensional network structure. Moreover, a comparison of the GPC elution curve showed the residual bitumen hardly changed due to carbon black released from DCR of SBS/DCRMB during the aging process of SBS/DCRMB, and the polymer molecules condensed to larger units. However, the remaining bitumen in SBSMB had changed evidently and the polymer degraded to smaller molecules. Meanwhile the rheological testing results, including multiple stress creep recovery, linear amplitude sweep and bending beam rheometer, declared that the SBS/DCRMB is superior to SBSMB before and after aging.
Nanoindentation has been applied in the field of asphalt mixtures, but, at the nano-scale, changes in the composition of the mixture and material properties can have a significant impact on the ...results. Therefore, it is necessary to investigate the feasibility of nanoindentation tests on different types of asphalt mixtures with different gradations and the influence of material properties and test methods on nanoindentation results. In this paper, the nanoindentation test results on three kinds of asphalt mixture (AC-13, SMA-13, and OGFC-13) with different aggregate gradations were investigated. The load-displacement curves and moduli obtained from the nanoindentation tests were analyzed. In addition, nanoindentation tests were carried out before and after polishing with different ratios of filler and asphalt (RFA) (0.8–1.6). On this basis, the morphology of asphalt specimens with different RFAs is observed by scanning electron microscopy (SEM) imaging. The results indicate that using the nanoindentation test to characterize the mechanical behavior of asphalt mixture, the confidence level of the dense-graded mixture is low, and non-dense-graded mixtures are used as much as possible. Moreover, results illustrate that the nanoindentation modulus tends to increase as the RFA increases. and the SEM chart shows that the higher the mineral powder content in the mastic, the more complex the bitumen and mineral powder interaction surface, confirming the influence of mineral powder content on the nanoindentation test results. Furthermore, the effect of polishing is almost insignificant.
To identify novel immune-related genes expressed in primary Sjögren's syndrome (pSS).
Gene expression profiles were obtained from the Gene Expression Omnibus (GEO) database, and differentially ...expressed genes (DEGs) were screened. The differences in immune cell proportion between normal and diseased tissues were compared, weighted gene co-expression network analysis was conducted to identify key modules, followed by a protein-protein interaction (PPI) network generation and enrichment analysis. The feature genes were screened and verified using the GEO datasets and quantitative real-time PCR (RT-qPCR).
A total of 345 DEGs were identified, and the proportions of gamma delta T cells, memory B cells, regulatory T cells (Tregs), and activated dendritic cells differed significantly between the control and pSS groups. The turquoise module indicated the highest correlation with pSS, and 252 key genes were identified. The PPI network of key genes showed that
, and
had a relatively higher degree. In addition, the key genes were mainly enriched in coronavirus disease-COVID-2019, hepatitis C, and influenza A. Fourteen feature genes were obtained using the support vector machine model, and two subtypes were identified. The genes in the two subtypes were mainly enriched in the JAK-STAT, p53, and toll-like receptor signaling pathways. The majority of the feature genes were upregulated in the pSS group, verified using the GEO datasets and RT-qPCR analysis.
Memory B cells, gamma delta T cells, Tregs, activated dendritic cells,
, and the feature genes possible play vital roles in the development of pSS.
ER1626, a novel compound, is a derivate of indeno-isoquinoline ketone. This study was designed to evaluate the biological activity and potential anti-tumor mechanism of ER1626.
MTT assay, scratch ...assay and flow cytometry were used to determine cell proliferation, cell migration and cell cycle distribution as well as cell apoptosis on human breast cancer MCF-7 cells and endometrial cancer Ishikawa cells. We also explored the antiangiogenic effect of ER1626 on HUVEC cells and chicken embryos. The expression of estrogen receptor protein was investigated with western-blot analysis.
ER1626 down-regulated the expression of estrogen receptor α protein and up-regulated β protein in MCF-7 and Ishikawa cells. The value of IC50 of ER1626 on MCF-7 and Ishikawa cells were respectively 8.52 and 3.08 µmol/L. Meanwhile, ER1626 decreased VEGF secretion of MCF-7 and Ishikawa cells, disturbed the formation of VEGF-stimulated tubular structure in HUVEC cells, and inhibited the angiogenesis on the chicken chorioallantoic membrane. Scratch assay revealed that ER1626 suppressed the migration of MCF-7, Ishikawa and HUVEC cells. In addition to induction tumor cell apoptosis, ER1626 arrested cell cycle in G1/G0 phase in MCF-7 cells and G2/M phase in Ishikawa cells.
In conclusion, our results demonstrated that ER1626 has favorable bioactivities to be a potential candidate against breast cancer and angiogenesis.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background
Metabolites present in human urine can be influenced by individual physiological parameters (e.g., body mass index BMI, age, and sex). Observation of altered metabolites concentrations ...could provide insight into underlying disease pathology, disease prognosis and diagnosis, and facilitate discovery of novel biomarkers.
Methods
Quantitative metabolomics analysis in the urine of 183 healthy individuals was performed based on high‐resolution liquid chromatography–mass spectrometry (LC–MS). Coefficients of variation were obtained for 109 urine metabolites of all the 183 human healthy subjects.
Results
Three urine metabolites (such as dehydroepiandrosterone sulfate, acetaminophen glucuronide, and p‐anisic acid) with CV183 > 0.3, for which metabolomics studies have been scarce, are considered highly variable here. We identified 30 age‐related metabolites, 18 BMI‐related metabolites, and 42 sex‐related metabolites. Among the identified metabolites, three metabolites were found to be associated with all three physiological parameters (age, BMI, and sex), which included dehydroepiandrosterone sulfate, 3‐methylcrotonylglycine and N‐acetyl‐aspartic acid. Pearson's coefficients demonstrated that some age‐, BMI‐, and sex‐related compounds are strongly correlated, suggesting that age, BMI, and sex could affect them concomitantly.
Conclusion
Metabolic differences between distinct physiological statuses were found to be related to several metabolic pathways (such as the caffeine metabolism, the amino acid metabolism, and the carbohydrate metabolism), and these findings may be key for the discovery of new diagnostics and treatments as well as new understandings on the mechanisms of some related diseases.
Metabolites in human urine are affected by individual physiological parameters, and this study identified 30 age‐related, 18 BMI‐related, and 42 sex‐related metabolites. Among them, 3 metabolites were found to be associated with age, BMI, and sex, and the highly correlated pathways discovered based on metabolic pathway analysis may be the key to discovering new diagnosis and treatment methods.
•The fatigue crack density was defined according to the initial radius of sample and effective radius of undamaged part.•The secant method was conducted to partition the fatigue crack density curve ...into three stages.•Fatigue crack density growth rate at the steady growth stage was proposed to evaluate the crack resistance of asphalt materials.•The effect of stress level, healing and ratios of filler to asphalt were analyzed.
Fatigue crack is one of the most common distresses in asphalt pavement. In this study, the fatigue crack behaviors of asphalt binders were evaluated under repeated cyclic controlled-stress loadings. Fatigue crack density, defined by the initial sample radius and effective radius of the undamaged part during fatigue testing, was used as an indicator. Also, an effective radius function was developed using the torque equilibrium principle and dissipated strain energy (DSE) equilibrium principle. The data revealed that fatigue crack density of asphalt binder manifested three changing tendencies, in which the secant method was employed to partition their profiles based on concavity and convexity characteristics. Specimens made of #50, #70 unmodified asphalt, SBS modified asphalt, and #50 asphalt mastic, respectively, were tested by time sweep tests on a Dynamic Shear Rheometer (DSR) at different stress levels and rest time. The variations in fatigue crack density at the three stages, as well as the changes in fatigue crack density growth rate in the second stage, were all analyzed. The asphalt binder showed fatigue crack density profiles composed of three stages: crack initiation, steady growth, and unstable growth. Stage II had the smallest increase in fatigue crack density among the three stages but underwent more than 50% load cycles throughout the whole fatigue process. Hence, fatigue crack density growth rate (RD) could be used to evaluate the fatigue resistance of asphalt binders. A positive power-law relationship between RD and stress level was recorded since higher stress levels meant more serious damage. By contrast, RD displayed a negative power-law relationship with resting time, revealing that the rest time, that is, self-healing, effectively postponed the fatigue crack propagation rate.
Recycled from waste tires, crumb rubber (CR) is a common additive material using in transport infrastructures to improve the mechanical performance of asphalt mixture. The styrene-butadiene-styrene ...(SBS) and CR composite modification technology were employed to prepare SBS/CR composite modified asphalt (CMA) binders. To study the effect of CR contents and control modes on the fatigue performance of asphalt binders, the Dynamic Shear Rheometer (DSR) tests, including stress/strain sweep tests and controlled-stress/strain time sweep tests, were conducted to calculate the fatigue crack density as loading cycles. Based on the test data, the fatigue crack density evolution and the modified Paris’ law were used to characterize the fatigue performance of SBS/CR CMA binders. A unified fatigue parameter was proposed to evaluate the fatigue resistance and optimize the CR content of SBS/CR CMA binders under two control modes. Results demonstrated that the fatigue crack density only experienced two stages (the crack initiation stage and the steady growth stage) under the controlled-strain loading, while the asphalt binder sample shows obvious structural failure (e.g., stepping into the unsteady growth stage) under controlled-stress loading. The smaller value of the proposed index, lnA/(n+1), indicated the better capacity of fatigue crack resistance and that of a certain type of asphalt binder under two control modes were almost identical. Furthermore, the value of SBS/CR CMA binder with 40 wt% CR was −6.81 showing the best fatigue performance among these asphalt binders, and the CR contents and the values of proposed index followed a linear relationship.
In long-term operations, seasonal imbalance in the thermal load may adversely affect the heat transfer performance of the energy piles, potentially resulting in thermal accumulation within the ground ...and eventual system failure. The heat transfer performance of energy pile systems during long-term operation under unbalanced thermal loads must be investigated. Moreover, the design parameters of energy piles are usually constrained by the requirements of foundation structural design, resulting in energy piles being densely arranged. Hence, the influence of pile spacing on the heat exchange performence of energy piles must be comprehensively understood. In this study, two- and three-dimensional energy-pile heat transfer models were established and innovatively coupled based on an engineering project currently under design. Numerical simulations were performed to investigate the heat transfer behavior of energy-pile groups subjected to unbalanced thermal loads and the effect of pile spacing on their heat exchange performance. Furthermore, design recommendations regarding the determination of the proportion of thermal loads to be borne by the energy piles in a hybrid GSHP system were provided. The results indicate that the proposed 2D-3D coupled modeling approach is able to simulate the heat exchange performance of large-scale energy pile groups. Pile spacing considerably affects the long-term thermal performance of energy-pile groups, especially in cases with small pile spacings. The influence of pile spacing on the heat exchange capacity of energy piles can be considered in the design phase by incorporating a group effect coefficient η, which are calculated to be 0.165, 0.470, 0.732, and 1 for pile spacings of 2 m, 4 m, 6 m, and 10 m, respectively.
The study aimed to investigate the effect of early mobilization combined with early nutrition (EMN) on intensive care unit-acquired weakness (ICU-AW) in intensive care unit (ICU) settings compared ...with early mobilization (EM) or routine care.
A prospective, dual-center, randomized controlled trial was conducted. The control group underwent standard care without a pre-established routine for mobilization and nutrition. The EM group underwent early, individualized, progressive mobilization within 24 h of ICU admission. The EMN group underwent early mobilization, similar to the EM group plus guideline-based early nutrition (within 48 h of ICU admission). The primary outcome was the occurrence of ICU-AW at discharge from the ICU. Secondary outcomes included muscle strength, functional independence, organ failure, nutritional status, duration of mechanical ventilation (MV), length of ICU stay, and ICU mortality at ICU discharge.
A total of 150 patients were enrolled and equally distributed into the three groups. Patients undergoing routine care only were more susceptible to ICU-AW upon ICU discharge than those in the EM or EMN groups (16% vs. 2%; p = 0.014 for both), and had a lower Barthel Index than others (control vs. EM/EMN: 57.5 vs 70.0; p = 0.022). The EMN group had improved muscle strength (p = 0.028) and better nutritional status than the control group (p = 0.031). Both interventions were associated with a lower ICU-AW (EM vs. control: p = 0.027, OR 95% CI = 0.066 0.006-0.739; EMN vs. control: p = 0.016, OR 95% CI = 0.065 0.007-0.607).
EM and EMN had positive effects. There was little difference between the effects of EM and EMN, except for muscle strength improvement. Both EM and EMN may lead to a lower occurrence of ICU-AW and better functional independence than standard care. EMN might benefit nutritional status more than usual care and promote improvement in muscle strength.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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