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In this study, we focused on the antioxidant activities in NRK52e cells, a rat renal proximal tubular cell line, of five new phenylpropanoid glycosides, paulowninosides B–F (Compounds 1–5), which were isolated from the n-BuOH soluble part of the 50 % acetone-H2O extract of the flowers of Paulownia fortunei. The structures of the compounds were determined by extensive spectroscopic analyses (UV and IR spectroscopy, HR-ESI-MS, 1D-, 2D-NMR). The levels of antioxidant activities of the compounds were determined by real-time cell analysis (RTCA) of NRK52e cells that underwent H2O2-induced oxidative injury. Compounds 1, 3 and 5 exhibited excellent antioxidant activities compared with control group.

Epimesatines A-I, nine undescribed prenylated flavonoids, along with ten known analogues, were isolated from the aerial parts of Epimedium sagittatum Maxim. The structures and absolute configurations of epimesatines A-I were determined using a combination of spectroscopic data, Rh

Calcined ginger nut (CGN) has been applied in grouting mortars for anchoring unstable earthen sites, but the lack of scientific research limits its application. In this study, CGN-based grouts admixed with fly ash (F), quartz sand (S), or both are evaluated. To explore the optimal mixture ratios, three types of mixing groups (five proportion gradients in each group) are established. All the grout specimens are buried and maintained outdoors, and their physical (shrinkage rate, density, elastic wave velocity, and permeability) and mechanical properties are continuously examined over 180 days. The solidification processes at different ages are simultaneously observed by means of scanning electron microscopy (SEM) images. The results indicate that the physical properties of grouts are influenced significantly by initial moisture content but then remain steady for approximately 15 days. Quartz sand can effectively reduce the shrinkage rate of grouts as well as adjust their density and permeability, and might be considered as an ideal mixing material for CGN. In the solidification process, grouts are rapidly solidified after the initial hydration reaction, and the carbonation reaction in the later stage constantly improves their mechanical strength, with physical properties kept relatively stable. SEM images show fly ash and quartz sand particles are cemented by CaCO3 crystals. Through comprehensive comparison, the grouts with the mass ratio of CGN and S at 1:1 are found to better satisfy requirements that grouts should be compatible with earthen sites.

Based on the structures of nicotinic acid and chlorfibrate, a series of new H2S donors were synthesized and their anti-atherosclerosis activities using Ox-LDL RAW 264.6 cells as model were evaluated. The release test showed that all the compounds could release H2S effectively and showed low cytotoxicity. In the bioactivity experiments, compounds 1, 3, 9 and 14 increased the survival rate of HUVEC cells treated by ox-LDL; among four compounds, compounds 1 and 3 displayed higher activity than the others. In the foam cell model, compounds 1 and 3 were found to inhibit the formation of foam cells and significantly reduced the content of TC and FC in foam cells. They had more obvious effects on lipid reduction than those of nicotinic acid and chlorfibrate. In anti-oxidation, compounds 1 and 3 significantly reduced ROS and MDA and increased the expression level of SOD, whereas the precursor compounds, niacin and chlorfibrate had little antioxidant effect. In addition, both compounds also inhibited the inflammatory response in foam cells, with reducing pro-inflammatory factor TNF-α and increasing anti-inflammatory cytokine IL-10. WB assay showed that the tested compounds inhibited the expression levels PI3K, Akt and NF-κb proteins. In conclusion, the compounds as H2S donors could protect HUVEC cells from damage and inhibit the formation of foam cells by inhibiting PI3K/Akt/NF-κb signal pathway. All these suggest the compounds have potential to be candidate for anti-atherosclerosis medicines.

A series of H2S CO dual-donors [Mn(CO)4CS2NR1R2] was synthesized, and evaluated from toxicity and bioactivity. The CO H2S measuring test showed all the complexes not only released CO, but released H2S. The resulting data of cytotoxicity showed all the complexes had activities against the cell proliferation; among them, complexes 1, 2 and 7 displayed higher activities than the others, and their potencies were close to cis-platinum (DDP); whereas the precursors A1-A22 had almost no activities against all five tumor cell lines and W138 cell line proliferation. It is worth noting that complex 1 displayed the highest activity to MCF-7, complex 2 displayed the highest activity to HePG2, and complex 7 showed selectivity inhibition to both A549 and HeLa. The developmental toxicities of the complex were assessed using zebrafish embryos. The results showed complexes 1 and 2 had effect on the mortality and hatching rate of zebrafish embryos in dose-dependent manner. They caused zebrafish malformations when they were over 10 μM. Meanwhile, they displayed dose-dependent toxicities to larval zebrafish. In the test of bio-activities, complexes 1 and 2 had strong anti-inflammatory activities; they not only down-regulated the expression levels of iNOS and TNF-α, up-regulated the expression of HO-1 and IL-10, but also up-regulated COX-2 levels. In contrast, the precursor compound (A1 or A2) displayed lower anti-inflammatory activity than the corresponding complex, which suggests both the CO and H2S from the complex took synergistic effects in the process of anti-inflammation. In addition, the complex showed antihypertensive effect and myocardial protection. This effect also possibly resulted from this synergistic effect. All these suggest the complexes have potential to be candidate medicines.

Conservation practices employed thus far have proven that single materials cannot suitably protect earthen sites. This study compares the effectiveness of single and composite materials, to explore whether composite materials are potential candidates for use in conservation. Soils from the Great Wall of Yongchang, Gansu Province, China, were treated with five types of materials, namely, inorganic materials, organic products, composite materials composed of organic and inorganic materials in different orders, and ethanol. Changes in the colour, weight, mechanical properties, water resistance, microstructures, and element composition were evaluated after treatment. Better reinforcing effects were obtained by applying an organic material and then using an inorganic material. Results showed that a composite material with reasonable reinforcing sequence can greatly improve the properties of soils; hence, composite materials are promising for use in the protection of cultural relics in the future.

During the process of archaeological excavation in the regions of Southeast China, collapse of test square usually occurs due to poor site-specific conditions. In this paper, the fast Lagrangian analysis of continua in three dimensions (FLAC3D) is employed to reveal the behaviors of test square. Taking the archaeological works in Liangzhu prehistoric earthen sites as the research background, the paper first introduces the geological setting, excavation procedure and monitoring scheme of the studied test square. Then, the deformation of four sides of the test square is modeled using FLAC3D. By comparison, it shows that the numerical results are consistent with the results from field monitoring. The result suggests that the numerical simulation can be effectively applied to representing the actual behaviors of the test square, which is helpful for determination of excavation scheme and stability evaluation of the test square during archaeological excavation. Keywords: Prehistoric earthen site, Archaeological excavation, Test square behaviors, Field monitoring, Numerical simulations

Historical relics of Jurassic sandstones in southwest China have been subjected to weathering damage. Exfoliation, characterized by the detachment of multiple thin stone layers sub-parallel to the stone surface, is common in sandstone heritage sites. However, its mechanism of action remains poorly understood. In this study, a conceptual model of exfoliation is drawn from the literature and field investigations. To quantitatively determine the exfoliation mechanism, a range of non-destructive field-based methods (surface hardness, water absorption test, roughness, and amplitude of residual spalling layers) and laboratory analyses (scanning electron microscopy (SEM) and X-ray diffraction (XRD)) are adopted as weathering agents for separated detachments. In addition, the grain and pore sizes of weathering products are analyzed using digital image techniques. The results show that the roughness, water absorption coefficient, and pore size in sandstone surfaces increase from the inner layer to the outer layer, and their hardness and grain size decrease, respectively. The proportions of quartz, dolomite, and illite increases from the interior to the exterior, whereas the proportion of feldspar decreases correspondingly. The residual column strip structure derived from feldspar alteration and a mixed montmorillonite-illite mineral layer can be observed in the SEM images. It can be inferred from surviving environmental analysis that comprehensive actions from solar radiation, acid rain attack and capillary rise lead to sandstone exfoliation. In addition, the alteration of feldspar plays an important role during sandstone exfoliation. The results of this study enhance our understanding of the exfoliation of the Jurassic sandstone of the Chongqing Danzishi rock carvings in China.

Three new alkaloids, rehmanalkaloid A-C (1-3), and a new iridoid glycoside, rehmaglutoside L (4), together with nine known compounds, including (8S)-7,8-dihydrogeniposid (5), diglycoside (6), monomelittoside (7), mussaenoside (8), darendoside A (9), syringing (10), phenyl-6-O-β- d -xylopyranosyl-O-β- d -glucopyranoside (11), (7R, 8S)-4,9-dihydroxy-3,3′-dimethoxy-7,8-dihydrobenzofuran-1′-propanalneolignan (12), and trans-liovil (13), were isolated from a 95% EtOH extract of dried roots from Rehmannia glutinosa. Their structures were determined by extensive spectroscopic (UV, IR, HR-ESI–MS, and 1D and 2D NMR) analyses. Additionally, compounds 4-8 (iridoid glycosides) were evaluated for their protective effects on H714444444444444444444466666666669c2 cardiocytes impaired by doxorubicin. Among them, compounds 4-8 exhibited protective effects against DOX-induced cardiotoxicity.

Image reconstruction from radio-frequency (RF) data is crucial for ultrafast plane wave ultrasound (PWUS) imaging. Compared with the traditional delay-and-sum (DAS) method based on relatively imprecise assumptions, sparse regularization (SR) method directly solves the inverse problem of image reconstruction and has presented significant improvement in the image quality when the frame rate remains high. However, the computational complexity of SR is too high for practical implementation, which is inherently associated with its iterative process. In this work, a deep neural network (DNN), which is trained with an incorporated loss function including sparse regularization terms, is proposed to reconstruct PWUS images from RF data with significantly reduced computational time. It is remarkable that, a self-supervised learning scheme, in which the RF data are utilized as both the inputs and the labels during the training process, is employed to overcome the lack of the “ideal” ultrasound images as the labels for DNN. In addition, it has been also verified that the trained network can be used on the RF data obtained with steered plane waves (PWs), and thus the image quality can be further improved with coherent compounding. Using simulation data, the proposed method has significantly shorter reconstruction time (∼10 ms) than the conventional SR method (∼1-5 mins), with comparable spatial resolution and 1.5-dB higher contrast-to-noise ratio (CNR). Besides, the proposed method with single PW can achieve higher CNR than DAS with 75 PWs in reconstruction of in-vivo images of human carotid arteries.

Many studies reported the chlorite dissolution kinetics in acidic pH—resulting in the development of chlorite dissolution rate law covering the pH and temperature dependence—but they rarely discussed how various intrinsic factors, including chlorite types, structural complexity, and surface roughness (refers specifically to the ratio between Brunauer–Emmett–Teller surface area, BET SA, and geometric surface area, GSA, in this paper), influenced the chlorite dissolution rate or the mechanism for dissolution congruency. In this study, results obtained from mixed-flow reactor experiments performed on a Mg-rich chlorite, over a pH range of 2–6 at 25 °C and 95 °C, indicated that pH and temperature control not only the chlorite dissolution rate but also the congruency of element release. Low pH facilitated the dissolution of Fe from chlorite interlayers and caused incongruent element release rates at 25 °C, while higher temperature experiments at the same pH overcame the differences in surface reactivity between the interlayer and the tetrahedral-octahedral-tetrahedral (TOT) layer, and finally evolved into congruent dissolution. The lower pH also made chlorite dissolution more resistant to varying flow rates. A dissolution rate constant of 10–10.51 mol/m2/s, a reaction order of 0.32, and activation energy of 42.03 kJ/mol were determined for the Mg-rich chlorite dissolution kinetics at 25 °C, in an acid-enhanced mechanism. Longer-term reactive transport modeling (RTM) on the chlorite dissolution demonstrated that low pH and large specific surface area (SSA) decreased the chlorite percentage, bulk surface area, and saturation index quicker, and in a non-linear fashion. Chlorite with higher SSA lost more bulk surface area (BSA) than that with lower SSA, when the same mass of chlorite was dissolved. Through tabulating and recalculating a series of data from the literature, the combined effects of intrinsic and extrinsic factors—including chlorite type, BET SA/GSA ratio, and temperature—were explored. Fe-rich chlorite dissolves faster than Mg-rich chlorite in acid and neutral pH, due to the oxidative dissolution mechanism. The chlorite dissolution rate constant is linearly and positively correlated to BET SA/GSA for the same type of chlorite (Fe-rich and Mg-rich). Higher temperatures help reduce the effects of extrinsic and intrinsic factors on chlorite dissolution rates.

Earthen sites in northwest China represent a precious cultural heritage; however, these sites have been seriously damaged by weathering. Chemical consolidation treatment is a widely accepted conservation method, and PVA solution with a high degree of alcoholysis has exhibited potential for improving the strength of soil. However, research on the influence of the PVA solution on the wettability of these earthen sites is rarely reported. Therefore, the aim of this study is to investigate the change in wettability of earthen sites protected with the PVA by laboratory experiments. First, the compressive strength and wettability of soil specimens are analysed with varying PVA content, water content, and drying temperature. The results indicate that the soil strength and hydrophobicity are highest when the PVA content in the soil is 1.0 wt%. The relationship between the soil hydrophobicity and water content follows a one-peak distribution, whereas the hydrophobicity decreases with increasing in drying temperature and is lost when the drying temperature is 80 °C or more. Second, factors influencing the wettability of the composite soil are discussed, and water vapour permeability of 1 cm thick composite soil is investigated in conjunction with exfoliation of surface crust. Finally, the feasibility of protecting different parts (i.e. the upper, middle, and lower parts) of earthen sites with PVA is briefly discussed, and it is emphasised that the wettability should be considered as crucial evaluation criterion for the protection of earthen sites.

Sandstone was widely used in the construction of monuments and sculptures in ancient times; numerous archaeological sites still remain along the Silk Road. Deterioration of the archaeological sites is one of the most serious problems that needs urgent attention. Organosilicon material has been considered to be an effective type of chemical consolidant for heritage structures that need strengthening. In recent years, the negative effects of organic materials have gradually been realized, e.g., shorter life and poorer compatibility. Therefore, inorganic materials have been re-evaluated by conservation researchers because of their long-lasting effects and good compatibility with stone substrates. An innovative inorganic silicate solution based on a potassium silicate solution, a high mole ratio potassium silicate solution, was developed. This paper describes the characterization of the new material as well as results from testing after treatment with different concentrations and consolidation times. In this study, the authors aim to explore if the newly developed inorganic consolidant has potential for future use in sandstone treatment. The effectiveness of the new inorganic consolidant was evaluated in terms of absorbed consolidant amount, mechanical properties (e.g., surface hardness, ultrasonic wave velocity, elasticity modulus and compressive strength modulus), and salt crystallization resistance. The treated groups showed better mechanical strength than the control group. The salt-resistant ability of the treated samples was also greatly improved. According to the laboratory tests, the new inorganic silicon consolidant holds great potential for reinforcing weathered sandstone.

There are many studies examining the school district housing premium, and conclusions regarding the premium are quite diverse. Therefore, it is necessary to conduct an integrated analysis of the relevant literatures to determine the factors causing the premium, and to explore logically the relationship between housing prices and high quality basic education resources. Based on this goal, a theoretical framework is designed to analyze the incremental effect of high quality basic education resources on housing prices. Using the meta-analysis method, this study discusses the problem of the Chinese school district housing premium based on three aspects of education, namely location, stage, and characteristics. The study finds that education resources in the compulsory education stage have a positive impact (5.5 %) on housing prices. Compared with distance and quantity, the quality of schools has the highest premium rate, which is 7.2 %. The premium rate of education resources in non-first-tier cities (5.8 %) is higher than that in first-tier cities (2.8 %). We conclude that the connection between compulsory education and household registration is the key driving force behind the high housing premium in China.

A new bisepoxylignan dendranlignan A (A1) and the known compound lantibeside D (D2) was isolated from Chrysanthemum Flower, the dried capitulum of Dendranthema morifolium (Ramat.) kitam. Their structures were determined on the basis of extensive spectroscopic methods, including 1D-NMR, 2D-NMR and MS data. Additionally, A1 and D2 were evaluated for their effects on the production of inflammatory mediators in H9c2 cardiomyocytes stimulated with lipopolysaccharide (LPS). Results demonstrated that A1 and D2 decreased LPS-induced production of inflammatory cytokines TNF-α, IL-2 and IFN-γ in H9c2 cells. Both compounds also decreased the nuclear localization of c-JUN, p-P65 and p-IRF3, but did not affect the level of TLR4. Molecular docking indicated that A1 and D2 occupied the ligand binding sites of TLR4-MD2. In the present study, we for the first time discovered a new bisepoxylignan compound A1, and found that this compound has a potential to inhibit inflammation by inhibiting TLR4 signaling.

In this study, calcined ginger nuts (CGN) grouts admixed by fly ash (F) and quartz sand (S) was investigated on its suitability for anchoring use in earthen sites. According to requirement for the consistency of grout, the mix proportions were determined with 0.45 for CGN_F, 0.33 for CGN_S and 0.35 for CGN_F_S, by mass, to study their physical and mechanical property and durability. Test results indicated that use of fly ash can prolong the initial setting time of grout and admixture by fly ash and quartz sand leaded to lowest density and shrinkage, higher porosity, and highest strength. Accelerated aging tests indicated that admixture by fly ash led to a high resistance to fluctuation of temperature and humidity, sulfate attack and alkali environment; meanwhile, admixture by quartz sand resulted in high resistance to freeze-thaw action and water environment. As a compromise, CGN_F_S can get predominant durability. The paper shows that CGN_F_S grout is basically compatible to earthen sites and suitable for anchoring use in the conservation of earthen sites in terms of workability and durability.

Thermal conductivity of soils is an important parameter in heat and water transfer analysis of soils. Here, a modified model was proposed to calculate the saturation-dependent thermal conductivity of fine-textured soils from the completely dry condition to the full water saturation. In the study, we developed a new parallel-series model for calculating the thermal conductivity of soils at the completely dry condition with a weighting parameter. The weighting parameter can be calculated using the ratio of the thermal conductivity of air to the thermal conductivity of solid grains. We also proposed a simplified equation to calculate the parameter a of the model proposed by Bi et al. using sand content and thermal conductivity of soils at the full water saturation. Substituting the new parallel-series model and the simplified equation for the parameter a into the model proposed by Bi et al., yielding the modified model. The modified model was evaluated with 14 soil samples. Results show that the modified model could well estimate the thermal conductivity from the completely dry condition to the full water saturation. Keywords: Thermal conductivity, Saturation-dependent, Parallel-series model, Weighting parameter

Based on our previous research, a series of targeting hepatocellular carcinoma complexes, [R-Glycyrrhetinic acid-CH2C2H-[Co2(CO)6] (R = H, 1; R = NSAIDs-COOH, 2–4; R = Aromatic acid, 5–7; R = Amino acid, 8–10), were synthesized. The test showed they are slow CO releasers. Using HeLa, A549, HT-29, SMMC7721 and HepG2 cells as models, their activities against tumor cell proliferation were firstly evaluated. The resulting data show all the complexes displayed a good anti-proliferation activity against the HepG2 and SMMC-7721 liver cancer cells, and their IC50 values were in the range of 10.07–66.06 µM; compared with cis-platin (DDP), their activities were comparable or even better under the same condition. Among them, complexes 3, 4, 6 and 9 exhibited higher anti-proliferation activities against HepG2 and SMMC-7721 cell lines than the other cell lines. To confirm further these complexes have selectivity to the liver cells, the uptakes of complexes 3, 4, 6 and 9 by HepG2, HT-29, A549 and SMMC7721 cell lines were studied. The results show the cell uptake rates of the complexes by HepG2 cells and SMMC7721 cells were much greater than by other cells under the same condition. In following tests, the tested complexes displayed higher activities in inhibiting NF-kB, COX-2 and iNOS; and they induced HepG2 cells apoptosis by mitochondrial pathway, which assessed by staining with different fluorescent reagent DAPI, PI, Mito-Tracker Green and DCFH-DA. Meanwhile, the tested complexes up-regulated the expression levels of caspase-3 and Bax, down-regulated the Bcl-2 expression. In addition, they had no effect on zebrafish embryo survival, embryo hatching, embryonic movement, zebrafish malformation and zebrafish movement at below 0.5 µM. This suggests the complexes are potential candidates to be used in clinic for liver cancers.

Coastal loess is a special loess deposit that is distributed around the Bohai Sea. The primary objective of this study was to investigate the physical index, mineralogical characteristics and collapse potential of coastal loess. The secondary objective was to survey the effect of fine silt particles (particle size 5–10 μm, 6.64–7.64φ) on the collapse process. We tested the specific gravity, moisture content, dry density, Atterberg limits, grain size distribution, mineralogy, and collapsibility characteristics in a laboratory; generated scanning electron microscopy (SEM) images; and performed Mercury intrusion porosometry (MIP) tests. The results of this investigation indicated that coastal loess has a moderately severe collapse potential. The collapsibility coefficient decreases with an increase in the initial water content; it initially increases and then decreases with an increase in vertical pressure. As revealed by the MIP test, the collapse produces a smaller porosity, and the middle pores are primarily responsible for the collapse. The relationship of the collapsibility coefficient and particles with a diameter 7.64φ) have the same tendency in terms of their effect on collapse. These results and analyses are important to improve the engineering construction safety in coastal zone loess areas and achieve a better understanding of loess properties compared with loess from a typical loess-paleosol section.