Diagnosis and Monitoring of Tunnel Lining Defects by Using Comprehensive Geophysical Prospecting and Fiber Bragg Grating Strain Sensor.

Tunnel excavation induces the stress redistribution of surrounding rock. In this excavation process, the elastic strain in the rock is quickly released. When the maximum stress on the tunnel lining exceeds the concrete's load-bearing capacity, it causes cracking of the lining. Comprehensive geophysical exploration methods, including seismic computerized tomography, the high-density electrical method, and the ultrasonic single-plane test, indicated the presence of incomplete distribution of broken rock along the tunnel axis. Based on the geophysical exploration results, a carbon-fiber-strengthened tunnel simulation model was established to analyze the mechanical characteristics of the structure and provide a theoretical basis for sensor deployment. Fiber Bragg grating (FBG) strain sensors were used to measure the stress and strain changes in the second lining concrete after carbon reinforcement. Meanwhile, one temperature sensor was installed in each section to enable temperature compensation. The monitoring results demonstrated that the stress-strain of the second lining fluctuated within a small range, and the lining did not show any crack expansion behavior, which indicated that carbon-fiber-reinforced polymer (CFRP) played an effective role in controlling the structural deformation. Therefore, the combined detection of physical exploration and FBG sensors for the structure provided an effective monitoring method for evaluating tunnel stability.

Synergistic mechanism and degradation kinetics for atrazine elimination by integrated N-ZnO/g-C3N4/solar light/oxidant.

In this study, an N-ZnO/g-C3N4 (g-N-Z) Z-scheme photocatalyst was constructed using hydrothermal and high-temperature calcination. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and other tests were employed to characterise the catalytic material. The results showed that after N-ZnO modification, the separation efficiency of the photoinduced charge pairs and the utilisation of sunlight in the composites were improved. The kinetics experiments indicated that the degradation of atrazine (ATZ) in the g-N-Z/PDS/solar system was significantly better than that in the PDS/solar system. Under the action of the g-N-Z/PDS/solar system, the degradation rate of ATZ reached 83.88%, whereas in the PDS/solar system, it was only 31.76%. In addition, it was found that increasing the PDS concentration, g-N-Z dosage, and solution acidity effectively accelerated the removal of ATZ. The presence of HCO3-/CO32-, Cl-, and natural organic matter (NOM) inhibited the oxidation efficiency of the g-N-Z/PDS/solar system. Moreover, the presence of multiple reactive oxygen species (ROS) was confirmed using radical scavenging experiments to determine the contribution of each active component. Twelve oxidation intermediates of ATZ were obtained via liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the mechanism of enhanced ATZ degradation in the g-N-Z/PDS/solar system was proposed. Actual water and cyclic photocatalytic experiments further suggest that g-N-Z has good application value in water treatment.

Thermal Strain Detection for Concrete Structure Cold Shrinkage under Stress Constraint with FBG.

Additional strain increments occur in concrete subject to stress constraints during cold shrinkage, resulting in irregular deformation and reducing the concrete structure's stability. When an annular concrete structure is subjected to radial pressure, two tensile stress concentration zones will appear at the intersection of the inner wall and the diameter along the pressure direction. When exposed to low temperatures, the total strain in the tensile stress concentration zones is caused by the combined effect of applied stress strain and thermal strain. Then, the thermal strain of the structure can be obtained from the difference between the total strain and the applied stress strain. Gradient cooling was performed after applying radial pressure to the annular concrete using a counterforce device. The applied stress strain and total strain of the tensile stress concentration zones are measured by fiber Bragg grating (FBG) strain sensors fixed along the stress direction. According to the measurement results, the thermal strains of the concrete structure under the stress constraint are extracted to analyze the influence of the tensile stress constraint on the thermal strain of the concrete structure. In the temperature range of -40∘C∼20∘C, the thermal strains of the structure under radial pressures of 1500 N, 2000 N, and 3000 N are extracted, respectively. The thermal expansion coefficients are calculated based on the thermal strain of the structure. The free thermal expansion coefficient of concrete structures fluctuates around 11×10-6/∘C. When the temperature is reduced to 10∘C, the difference between the thermal expansion coefficient under the stress constraint and the free thermal expansion coefficient is the largest. When the temperature is reduced to -20∘C, the thermal expansion coefficients under each stress condition are close to the same. The results show that the stress confinement significantly inhibits the cold shrinkage of the concrete structure, and the inhibitory effect is gradually weakened when the temperature decreases.

Preparation and Evaluation of Liposomes and Niosomes Containing Total Ginsenosides for Anti-Photoaging Therapy.

Ginsenosides are the principal bioactive compounds of ginseng. Total ginsenosides (GS) contain a variety of saponin monomers, which have potent anti-photoaging activity and improve the skin barrier function. To enhance the efficiency of GS transdermal absorption, GS liposomes (GSLs) and GS niosomes (GSNs) were formulated as delivery vehicles. Based on the clarified and optimized formulation process, GSL and GSN were prepared. The structure, cumulative transmittance, skin retention, total transmittance, and bioactivity of GSLs and GSNs were characterized. GSL and GSN were shown to inhibit lipid peroxidation and increase the contents of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in human keratinocytes (HaCaTs). In addition, HaCAT cell migration, proliferation, and GS cellular uptake were significantly increased. The therapeutic effects of GSL and GSN were also evaluated in a rat model of photoaging. Histopathological changes were assessed in rat skin treated with GSL, GSN, or GS by hematoxylin-eosin (H&E) and aldehyde fuchsine staining. Malondialdehyde (MDA), SOD, GSH-Px, matrix metalloproteinases (MMPs), interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) expression levels were determined. Results indicated that the optimal formulation of GSL used soybean lecithin (SPC) as the phospholipid, with a lipid-drug ratio of 1:0.4 and a phospholipid-cholesterol ratio of 1:3.5. The optimal temperature for the preparation process of GSN by ethanol injection was 65°C, with a ratio of the organic phase to aqueous phase of 1:9. It was demonstrated that the cumulative release rate, skin retention rate, and total transmission rate of GSL-7 at 24 h were higher than those of GSN-4 and GS. GSL-7 significantly inhibited skin lipid peroxidation caused by ultraviolet (UV) radiation. In addition, GSL-7 reduced the contents of MMPs and inflammatory cytokines in skin tissue. In conclusion, GSL-7 may reduce skin aging caused by UV radiation and contribute to skin tissue repair.

Walnut Polyphenol Extract Attenuates Immunotoxicity Induced by 4-Pentylphenol and 3-methyl-4-nitrophenol in Murine Splenic Lymphocyte.

4-pentylphenol (PP) and 3-methyl-4-nitrophenol (PNMC), two important components of vehicle emissions, have been shown to confer toxicity in splenocytes. Certain natural products, such as those derived from walnuts, exhibit a range of antioxidative, antitumor, and anti-inflammatory properties. Here, we investigated the effects of walnut polyphenol extract (WPE) on immunotoxicity induced by PP and PNMC in murine splenic lymphocytes. Treatment with WPE was shown to significantly enhance proliferation of splenocytes exposed to PP or PNMC, characterized by increases in the percentages of splenic T lymphocytes (CD3+ T cells) and T cell subsets (CD4+ and CD8+ T cells), as well as the production of T cell-related cytokines and granzymes (interleukin-2, interleukin-4, and granzyme-B) in cells exposed to PP or PNMC. These effects were associated with a decrease in oxidative stress, as evidenced by changes in OH, SOD, GSH-Px, and MDA levels. The total phenolic content of WPE was 34,800 ± 200 mg gallic acid equivalents/100 g, consisting of at least 16 unique phenols, including ellagitannins, quercetin, valoneic acid dilactone, and gallic acid. Taken together, these results suggest that walnut polyphenols significantly attenuated PP and PNMC-mediated immunotoxicity and improved immune function by inhibiting oxidative stress.

In vitro effect of 4-pentylphenol and 3-methyl-4-nitrophenol on murine splenic lymphocyte populations and cytokine/granzyme production.

Gasoline exhaust particles (GEP) and diesel exhaust particles (DEP) are considered to be some of the most important air pollutants. Among the many constituents in these pollutant particles, 4-pentylphenol (PP) and 3-methyl-4-nitrophenol (PNMC) are considered important phenolics in GEP and DEP, respectively. The aim of this study was to investigate the effect of in vitro exposure to commercially-supplied PP and PNMC on populations of, and production of interleukin (IL)-2, IL-4 and granzyme-B by, mouse splenic lymphocytes. After in vitro exposure to PP or PNMC for 48 h, splenocyte viability was measured, cell phenotypes, e.g. B-cell (CD19), T-cells (CD3), T-cell subsets (CD4 and CD8), were quantified by flow cytometry and production of IL-2, IL-4 and granzyme-B was assessed via ELISA. The oxidative toxicity of PP and PNMC toward the splenocytes was also evaluated using measures of hydroxyl radical and malondiadehyde production and changes in glutathione peroxidase and superoxide dismutase activities. Results showed that in vitro exposure to PP and PNMC inhibited splenic cell parameters in a dose-related manner. Exposure to PP and PNMC decreased splenic T-lymphocyte populations and splenocyte production of cytokines and granzyme B, as well as induced oxidative stress in the splenocytes. The results also showed that the percentages of CD3(+) T-cells overall and of CD4(+) and CD8(+) T-cells therein, among exposed splenocytes, were reduced; neither compound appeared to affect levels of CD19(+) B-cells. Overall, the suppressive effects of PP were stronger than PNMC. The data here provide support for the proposal that PP-/PNMC-induced toxicity in splenocytes may be due at least in part to oxidative damage and that PP and PNMC - as components of GEP and DEP - might significantly impact on splenic T-cell formation/release of cytokines/granzymes in situ.

Isolation of a novel bio-peptide from walnut residual protein inducing apoptosis and autophagy on cancer cells.

BACKGROUND: Walnut is unique because they have a perfect balance of n-6 and n-3 polyunsaturated fatty acids. The increasing market demand of walnut lipids results in the large amount of the oil extraction residue. The walnut residue is rich in nutritional proteins, and the uneconomic use of the by-product discouraged the development of walnut industry. Anticancer peptides have recently received attention as alternative chemotherapeutic agents that overcome the limits of current drugs. The aim of this study was to investigate whether anticancer bioactive peptide is contained in walnut. METHODS: Walnut residual protein was hydrolyzed separately by five different proteases. The sequential purification of the hydrolysates was carried out by ultra-filtration, gel filtration chromatography and RP-HPLC to obtain a cancer cell growth inhibitory peptide. Cell cycle distribution, Annexin V-FITC/PI double staining, TUNEL assay, western blot and immunofluorescence for LC3-II assay were used to detect apoptosis and autophagy on cells. Cytokine production was measured by ELISA kits, macrophage phagocytosis was measured by neutral red uptake assay, nitric oxide production was measured by Griess reagent. RESULTS: The hydrolysates of walnut residual protein produced by papain under the optimal conditions (5 % substrate concentration and an enzyme-substrate ratio of 10 % at temperature 60 C for 3 h), showed significant growth inhibitory activity on MCF-7. The amino acid sequence of the purified peptide was identified as CTLEW with a molecular weight of 651.2795 Da. It is a novel bio-peptide with an amphiphilic structure. CTLEW induced both apoptosis and autophagy on MCF-7 cells, inhibited the cancer cells growth of Caco-2 and HeLa significantly, but did not show any cytotoxic activity against non-cancerous IEC-6 cells. Moreover, the bio-peptide enhanced proliferation and IL-2 secretion of spleen lymphocytes, promoted phagocytosis and NO production of macrophages. CONCLUSION: These results suggested that a novel bio-peptide, CTLEW inducing apoptosis and autophagy on MCF-7 cells can be released from walnut residual protein through papain hydrolyzing under the certain condition. The bio-peptide shows selective inhibition towards cancer cells growth and immunomodulatory activity.

Immunostimulatory activity of protein hydrolysate from oviductus ranae on macrophage in vitro.

Oviductus Ranae is the dry oviduct of Rana chensinensis, which is also called R. chensinensis oil. Oviductus Ranae is a valuable Chinese crude drug and is recorded in the Pharmacopoeia of the People's Republic of China. The aim of this study was to investigate the immunostimulatory activity of protein hydrolysate of Oviductus Ranae (ORPH) and to assess its possible mechanism. Immunomodulatory activity of ORPH was examined in murine macrophage RAW 264.7 cells. The effect of ORPH on the phagocytic activity of macrophages was determined by the neutral red uptake assay. After treatment with ORPH, NO production levels in the culture supernatant were investigated by Griess assay. The mRNA and protein expressions of inducible nitric oxide synthase (iNOS) were detected by RT-PCR and Western blotting. The production of TNF-α, IL-1ß, and IL-6 after treatment with ORPH was measured using ELISA assay. In addition, NF-κB levels were also investigated by Western blot. The results showed that ORPH enhanced the phagocytosis of macrophage, increased productions of TNF-α, IL-1ß, IL-6, and NO in RAW 264.7 cells, and upregulated the mRNA and protein expression of iNOS. Besides, NF-κB, levels in RAW 264.7 cells were elevated after ORPH treatment. These findings suggested that ORPH might stimulate macrophage activities by activating the NF-κB pathway.