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There is controversy regarding whether excess FGF23 causes left ventricular hypertrophy (LVH) directly through activation of fibroblast growth factor receptor 4 (FGFR4) in cardiomyocytes or indirectly through reductions in soluble Klotho (sK). We investigated the respective roles of myocardial FGFR4 and sKL in mediating FGF23-induced LVH using mouse genetic and pharmacological approaches. To investigate a direct role of myocardial FGFR4 in mediating the cardiotoxic effects of excess circulating FGF23, we administered rFGF23 to mice with cardiac-specific loss of FGFR4 (FGFR4 heart-cKO). We tested a model of sKL deficiency, hypertension and LVH created by the conditional deletion of FGFR1 in the renal distal tubule (FGFR1DT cKO mice). The cardioprotective effects of sKL in both mouse models was assessed by the systemic administration of recombinant sKL. We confirmed that FGF23 treatment activates PLCγ in the heart and induces LVH in the absence of membrane α-Klotho. Conditional deletion of FGFR4 in the myocardium prevented rFGF23-induced LVH in mice, establishing direct cardiotoxicity of FGF23 through activation of FGFR4. Recombinant sKL administration prevented LVH, but not HTN, in FGFR1DT cKO mice, consistent with direct cardioprotective effects. Co-administration of recombinant sKL with FGF23 in culture inhibited rFGF23-induced p-PLCγ signaling. Thus, FGF23 ability to include LVH represents a balance between FGF23 direct cardiac activation of FGFR4 and the modulating effects of circulating sKL to alter FGF23-dependent myocardial signaling pathways.

Microcapsules with toluene-di-isocyanate (TDI) as core and paraffin as shell for self-healing of concrete were prepared using melt condensation method, and the effects of preparation temperature, agitation rate and paraffin/TDI mass ratio on core fraction of microcapsules were studied. The size distribution and morphology of microcapsules were characterized by laser particle size analyzer and scanning electron microscopy (SEM). Components of the microcapsules were analyzed by Fourier transform infrared spectrometer (FTIR). Finally, the effect of microcapsules on self-healing ability of mortars was evaluated, which indicated that preparation temperature, agitation rate and paraffin/TDI mass ratio had significant effect on core fraction of microcapsules. The optimum microcapsules could be prepared with a paraffin/TDI mass ratio 1:2 and an agitation rate 600 rpm at 75 °C. The core fraction of microcapsules prepared with optimum parameters was 66.5%, and the particle size was between 30 and 300 µm, mainly concentrated on 90 μm. SEM showed that the microcapsules were regular spheres and the shell thickness was about 1/10 of the diameter. FTIR confirmed that the TDI was successfully encapsulated in the paraffin shell. Compared with the control mortar, compressive strength of the mortar with 3% microcapsules (by mass of cement) increased by 28.2%. The reserved ratio of compressive strength was 77.2% under 60% fc0 pre-load after 48 h self-healing. The cracks with a width of less 0.4 mm on the mortar were rapidly self-healed by the microcapsules in 6 h.

Layered double hydroxides (LDHs) with different particle sizes (75 nm, 115 nm, 180 nm and 300 nm which were marked with LDHs-75, LDHs-115, LDHs-180 and LDHs-300) were characterized by scanning electron microscope, UV–vis reflection and absorption spectrophotometer and laser scatter meter. Furthermore, this paper investigated the influence of LDHs with different particle sizes on the rheological properties of bitumen before and after ultraviolet aging by temperature susceptibility test, dynamic shear rheometer test (DSR) and IR spectra test (FTIR). The researches reveal that LDHs-180 hold the strongest UV shielding performance. The temperature susceptibility of pristine bitumen and LDHs-75, LDHs-115, LDHs-180, LDHs-300 modified bitumen after aging decreased by 9.01%, 6.36%, 3.98%, 2.15% and 5.49%, respectively, which indicate LDHs-180 is more beneficial to weaken the decrease of bitumen temperature susceptibility after aging. Similarly, LDHs-180 modified bitumen show less variation in rheological properties than other bitumen samples after aging. This implies that LDHs-180 could mitigate the influences of UV aging on the rheological properties of bitumen more availably. In addition, the FTIR analysis further shows that the carbonyl and sulfoxide index of LDHs-180 modified bitumen is the smallest after aging, which indicates LDHs-180 is more helpful for improving bitumen anti-UV aging properties than that of LDHs-75, LDHs-115 and LDHs-300.

Lignosulfonate (LS) grafted layered double hydroxides (LDHs) were prepared through covalent bonding with diisocyanate (diphenyl-methane-diisocyanate (MDI), toluene-2,4-diisocyanate (TDI) or isophorone diisocyanate (IPDI)), and were characterized by Fourier transform infrared (FTIR) spectrometer, X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet and visible (UV–vis) spectroscopy. The degree of grafting (Dg) and mass proportion (Mp) had also been calculated. Then LS grafted LDHs modified bitumen was investigated using high temperature storage stability, physical properties measurement and thin-layer chromatography with flameionization detection test. FTIR and XRD showed that LS was successfully grafted to LDHs via covalent linked by diisocyanate. SEM displayed that LS grafted LDHs represented a stable cross-linked structure and had weaker surface agglomeration compared to LDHs. Dg and Mp of LS grafted LDHs linked by MDI (LS-m-LDHs) respectively reached up to 71.68% and 2.53:1, representing excellent grafting effect. The UV–vis analyses displayed that LS grafted LDHs had better UV absorbing ability than LDHs, which had a combined effect of chemically absorbing and physically reflecting UV light. Storage stability test expressed that the compatibility between bitumen and LDHs was improved prominently by the grafting of LS. Before and after aging, the variations of retained penetration ratio (RPR), ductility retention rate (DRR), softening point increment (SPI), viscosity aging index (VAI) and the colloid stable index (CI) of LS grafted LDHs modified bitumen were smaller compared to LS modified bitumen and LDHs modified bitumen, which illustrated that LS grafted LDHs exhibited better anti-UV aging ability of bitumen in comparison with LDHs and LS. In improving the aging resistance of bitumen. LS-m-LDHs were superior to LS grafted LDHs linked by TDI and LS grafted LDHs linked by IPDI.

Alternaria alternata causes serious brown spot disease in tobacco. To effectively control the disease, we tested the antifungal effects of the essential oil from the buds of Syringa oblata Lindl. Twelve different compounds were identified by gas chromatography–mass spectrometry. The major constituents were eugenol (40.426%), eugenol acetate (28.784%), β-caryophyllene (21.989%), and α-caryophyllene (3.456%). Among these, the most active antifungal component was eugenol, exhibiting complete inhibition of mycelial growth. The minimum inhibitory concentration of eugenol against A. alternata was 150 μg/mL, and the minimum fungicidal concentration was 250 μg/mL. The effect of eugenol on the surface morphology and membrane integrity of A. alternata was studied by scanning electron microscopy (SEM) and fluorescent microscopy (FSM). SEM observations revealed shriveled hyphae, while FSM observations revealed a disrupted membrane in eugenol-treated samples. Further experiments confirmed that eugenol activated a membrane-active mechanism that increased the membrane permeability, as evidenced by extracellular conductivity measurements. Under field conditions, an in vivo assay indicated that eugenol emulsion was effective in protecting tobacco from brown spot infection. This study suggests that eugenol has the potential to be used as a fungicide to control tobacco brown spot disease caused by A. alternata.

Self-healing microcapsules show great potential in extending the service life of concrete, but it is a challenge to achieve the smart release of the healing agent from the microcapsules. In this research, Novel Microcapsules Raptured by Microwave (NMRM) with unique core–shell structure for self-healing concrete were successfully produced. The core content was calculated and the surface morphology and size distribution of NMRM were explored by Scanning Electron Microscope (SEM) and Dynamic Light Scattering (DLS). The temperature variations of specimens were monitored by a thermal infrared imager. Furthermore, the effects of NMRM dosage on the fundamental performance of concrete was investigated and self-healing behavior of the mortar and concrete were evaluated. As a result, rapture of microcapsules with 5% graphite can be quickly triggered under the microwave irradiation. The 60% fc0 pre-damaged concrete with 5% NMRM possessed 92.6% of CSRR. The purpose of this investigation is to provide a new trigger for microcapsule rupture on the specific location with cracks at the right time for self-healing concrete.

Phytophthora nicotianae causes serious black shank disease in tobacco. Syringa oblata essential oil and its main components were evaluated to develop an effective and environmentally friendly biocontrol agent. Eugenol, which exhibited the strongest activity, was intensively investigated in vitro and in vivo. The mycelial growth of P. nicotianae was inhibited by eugenol at a minimum inhibitory concentration of 200μgmL-1, and inhibition occurred in a dose-dependent manner. Extracellular pH and extracellular conductivity results indicated that eugenol increased membrane permeability. Flow cytometry and fluorescent staining results further showed that eugenol disrupted mycelial membranes but did not affect spore membrane integrity. The in vivo results confirmed that treatment of tobacco with various concentrations of eugenol formulations reduced disease incidence and better controlled against the disease. Our results suggested that the ability of eugenol to control tobacco black shank depended on its ability to damage mycelial membranes and that eugenol formulations have potential as an eco-friendly antifungal agent for controlling tobacco blank shank.

The surface free energy and related parameters of asphalt binder affect the wettability of asphalt binder to aggregate and its moisture sensitivity. In this research, the surface free energy and related parameters of SBS modified bitumen (SMB) after aging/rejuvenating were tested and analyzed. And then based on this data, the effect of common rejuvenator cashew shell oil and active isocyanate rejuvenators on the water damage resistance and moisture sensitivity were evaluated and predicted. The results indicated that the surface free energy of SMB decreased after aging, while rejuvenators all can enhance the surface free energy. The cohesion work of aged SMB increased after rejuvenating, and the adhesion work between aged SMB and granite were enhanced by 12.4% at least with the addition of rejuvenators, namely, rejuvenators can improve its cracking resistance and interface stability, and active rejuvenator hexamethylene diisocyanate showed the best performance. Water boiling test showed that the adhesion grade of SBS modified bitumen on granite decreased from adhesion grade 5 to adhesion grade 3 after aging, while active rejuvenators can bring the adhesion grade of aged SMB on granite to the original level. This paper would be helpful to understand the moisture resistance mechanism of rejuvenated SBS modified asphalt mixture with active regeneration technology.

The regeneration and reusing of reclaimed asphalt mixture can promote the recycling of waste building materials and the sustainable development of asphalt pavement. To further improve the properties of rejuvenated SBS modified asphalt, the effects of structural changes of SBS, and the colloidal stability of asphalt on the properties of binder were studied. And based on the results, bio-rejuvenator and active rejuvenator were applied to rejuvenate ultraviolet aged SBS modified asphalt (USMA), the impacts of rejuvenators on the composition, structure, physical and rheological properties of USMA were systematically investigated. The results show the decrease of colloidal index and the damage of SBS structure all have a serious adverse influence on the properties of binder. Bio-rejuvenator can rebalance the colloidal stability of ultraviolet (UV) aged binders, meanwhile active rejuvenator could react with the active terminal groups of broken SBS segments and partially rebuilds its crosslinking structure. And the physical and rheological properties of UV aged asphalt can be all basically restored by adding bio-rejuvenator; however bio-rejuvenator cannot restore the properties of USMA, which can only improve the low-temperature performance of USMA. While the addition of active rejuvenator greatly enhances the high-temperature performance of rejuvenated SBS modified asphalt. Furthermore, the combination of bio-rejuvenator and active rejuvenator can both recover the colloidal structure and damaged SBS structure of USMA, which obviously improves its high- and low-temperature properties overall. This paper would contribute to the realization of high-quality regeneration of reclaimed SBS modified asphalt.

Ion chelator can chelate calcium ions and migrate in cement-based materials to promote self-healing of cracks. This paper investigated the migration and self-healing abilities of ion chelator in cement-based materials by a novel method. In this method, control mortar without ion chelator and self-healing mortar with ion chelator are poured into the same mold, cracks at different locations of the two kinds of mortars are prefabricated, and the migration of ion chelator from self-healing mortar to the control mortar is assessed by observing the self-healing process of crack in control mortar. Meanwhile, the microstructure and chemical component of self-healing product in cracks at different locations of the control mortar was characterized through scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that the self-healing ability of control mortar is closely related to the migration distance of ion chelator. When the migration distance of the ion chelator was 2 cm, the crack with a width of 0.37 mm can be sealed after curing for 7 d. When the migration distance of the ion chelator was 5 cm, the crack with a width of 0.26 mm can also be repaired after curing for 7 d. Through SEM observation and XRD analysis, it can be found that the ion chelator promotes the formation of a large number of calcite crystals for sealing the cracks in the control mortar. However, the calcite crystals at the crack will become loose with the increase of the migration distance of the ion chelator.

To fully restore the performance of waste SBS modified asphalt mixture, better realize its recycling and application in high-grade pavement, achieve the concept of sustainable green development of asphalt pavement. In this paper, the synergistic effects of bio-rejuvenator and active isocyanate rejuvenators (including hexamethylene diisocyanate (HDI), diphenyl-methane-diisocyanate (MDI) and toluene-2, 6-diisocyanate (TDI)) on the chemical structure, physical and rheological properties of aged SBS modified bitumen were thoroughly investigated. Fourier infrared spectrum and Gel permeation chromatography analysis indicate the isocyanate groups of active rejuvenators react with hydroxyl or carboxyl group from the degraded SBS segments to form new amide groups that can reconnect the broken segments of aged SBS and partly restore its molecular weight distribution. From physical and rheological properties, bio-rejuvenator can restore the low-temperature properties by rebalancing the colloidal structure of aged binder, meanwhile, active rejuvenators can greatly improve the high-temperature performance of rejuvenated SBS modified bitumen with bio-rejuvenator through reconnecting the broken segments of aged modifier SBS. Furthermore, MDI with benzene ring structure is more conducive to enhancing the high temperature rutting resistance of rejuvenated SBS modified bitumen. While HDI can bring some flexible segments into the restored structure of SBS, which is more beneficial to improve its low-temperature cracking resistance of rejuvenated binder. And the fluorescence images further demonstrate isocyanate rejuvenators can partly restore the crosslinking network structure of aged modifier SBS in rejuvenated SBS modified bitumen. This research would be conductive to promoting the application of rejuvenated SBS modified bitumen into the construction of high standard pavement.

Ion chelator is a novel crystalline additive which can chelate Ca2+ and migrate in concrete to promote self-healing of surface crack and internal pore. In order to further explore the effect of ion chelator on hydration process of cement, the hydration heat, chemically bound water, compressive strength, hydration products, pore-size distribution and microstructure of cement paste with ion chelator were investigated in this paper. Results of the experiments showed that the ion chelator accelerated the hydration of the cement paste. Incorporation of ion chelator in cement greatly enhanced the chemically bound water content and the mechanical property. Compared with control cement paste, the chemically bound water content and compressive strength of cement paste with 0.5 wt% ion chelator increased by 13.3% and 16.8% after curing for 28 days. According to the DTA-TG and XRD tests, the ion chelator can promote the hydration of C3S and C2S, which was conducive to the generation of calcium silicate hydrate gels. Furthermore, the addition of ion chelator improved the pore-size distribution and microstructure of cement paste, and a large number of floccules and needles appeared in the pores of cement paste.

In order to evaluate the influence of silane coupling agent modified zeolite warm mix additives on the properties of asphalt, the physical and rheological properties as well as chemical structure of asphalt with zeolite, γ-ammoniapropyltriethoxysilane modified zeolite (KH550-zeolite) and γ-(2,3-epoxypropoxy)propytrimethoxysilane modified zeolite (KH560-zeolite) before and after thin film oven test (TFOT) aging were thoroughly investigated. The results showed that, compared with zeolite, KH550-zeolite and KH560-zeolite made the softening point of asphalt increase more, and whose penetration and ductility decrease less, which indicated that KH550-zeolite and KH560-zeolite (especially KH560-zeolite) could enhance the high-temperature properties and had less effect on the penetration and ductility of asphalt. The temperature susceptibility of asphalt was clearly reduced and the rutting factor (G*/sinδ) was enhanced after the introduction of silane coupling agent modified zeolites compared with zeolite. After the TFOT aging, the performance of asphalt with silane coupling agent modified zeolites (especially KH560-zeolite) had a little change. In a word, KH550-zeolite and KH560-zeolite as warm mix additives had a positive effect on the physical, rheological and anti-aging properties of asphalt.

Ion chelator is a kind of crystalline additive which can accelerate the precipitation of calcium carbonate in cracks of cement-based materials. In this paper, the influences of ion chelator and CO2-rich environment on self-healing capabilities of cement mortar were investigated. The mortars with or without ion chelator were subjected to two gas environments (air and CO2-rich) and three exposure conditions (no water, water contact and water immersion), respectively. The self-healing rate of cracks, water permeability and water absorption of the healed mortars, and microstructure of self-healing product were used to assess the self-healing capability of mortars. The results indicated that the self-healing ability of the mortars cured in CO2-rich environment is stronger than that of the mortars cured in air environment. The excellent self-healing ability of the mortars with ion chelator needs to be stimulated by water contact or water immersion. The relative permeability coefficient and water absorption coefficient of mortar with ion chelator in the CO2-rich environment under water contact or water immersion conditions were significantly reduced. In addition, the bottom surface crack of mortar has better self-healing ability than the top surface crack of mortar. The bottom surface crack up to 0.46 mm can be healed after curing for 28 d when the mortars with ion chelator were cured in the CO2-rich environment under water immersion condition. Scanning electron microscopy showed that the particle sizes of self-healing products (CaCO3) in bottom surface crack were larger than that in top surface crack.

Ion chelator can promote the self-healing process of cement-based materials. The aim of present study is to investigate the effect of ion chelator on microstructure and properties of cement-based materials under sulfate dry-wet cycle attack. The micromorphology and pore structure of mortar were characterized by scanning electron microscope (SEM) and nuclear magnetic resonance (NMR). The impermeability of mortar was evaluated by chloride diffusion coefficient. Meanwhile, mass loss, mechanical strength, and corrosion resistance coefficient (K) of mortar were measured. The results showed that ion chelator could improve microstructure and mechanical properties of cement-based materials by enhancing their self-healing ability. After 60 cycles of sulfate dry-wet, SEM showed that there was a large degree of erosion formed on the surface of control mortar (CM), while slight erosion occurred on the surface of mortar with ion chelator (MCA). NMR indicated that the proportion of harmful pores (≥0.1 μm) in CM and MCA was 50.19% and 42.86%, especially, the proportion of harmful pores from 0.25 μm to 25.0 μm in mortar is obviously reduced with the addition of ion chelator. And the compressive strength of MCA was 33.6% higher than that of CM, and the chloride diffusion coefficient of MCA was 25% lower than that of CM. Meanwhile, the mass loss ratios of CM and MCA were 1.78% and 0.91% and the K values of CM and MCA were 0.79 and 0.92 respectively. Conclusion can be drawn that ion chelator significantly improves the microstructure and properties of cement-based materials under sulfate dry-wet cycle attack.

The ambient temperatures have significant effect on self-healing capabilities of concretes with microcapsules. Self-healing capabilities of mortars with different shell composition (paraffin, paraffin/PE wax and nano-SiO2/paraffin/PE wax) microcapsules containing toluene-di-isocyanate under the temperature of 10 °C, 30 °C, 50 °C and 60 °C were investigated in this paper. The compressive strength, chloride diffusion coefficient and pore size distribution of mortars containing microcapsules before and after self-healing were characterized by mechanical property test, rapid chloride migration test and nuclear magnetic resonance, respectively. The crack healing ratio of mortars during self-healing period were measured. The self-healing capabilities of mortars containing different microcapsules raised with the increase from 10 °C to 50 °C. Nevertheless, when the temperature reached 60 °C, the self-healing capability of the mortar containing paraffin microcapsules (AM1) decreased obviously, while the self-healing capabilities of the mortars containing paraffin/PE wax microcapsules (AM2) and nano-SiO2/paraffin/PE wax microcapsules (AM3) were almost unchanged. The self-healing capability of AM3 was superior to that of AM1 and AM2 at the same temperature. The compressive strength recovery rate, chloride diffusion coefficient recovery rate and harmful pores ratios of AM3 after pre-damaged at 50 °C for 7 d self-healing were 94.1%, 81.2% and 47.3%, respectively. When the ambient temperature reached 50 °C, the surface cracks of the mortar with three kinds of microcapsules could be completely self-healed in 5 h. However, when the temperature raised to 60 °C, the healing ratio of the crack in AM1 with a width of 0.4–0.5 mm decreased to 49.52% after 6 h self-healing. Meanwhile, the surface cracks of AM3 could be completely self-healed less than 3 h.

Ion chelator is a novel crystalline admixture used for improving self-healing capability of cementitious materials. Studies quantifying this self-healing behavior are limited to fresh-water making it unclear under seawater containing magnesium, sulfate and chloride ions. Therefore, the purpose of this paper is to investigate the effects of ion chelator on pore structure, mechanical property and self-healing capability of seawater exposed mortar. The pore size distribution was evaluated by nuclear magnetic resonance (NMR). The self-healing ability was quantified by compressive strength recovery and visible crack closure test, while the composition of crack healing products was analyzed by X-ray diffraction (XRD). The results indicated that ion chelator improves pore structure and compressive strength of mortar under seawater immersion. After 90 days seawater immersion, the proportion of harmful holes (>0.1 μm) in mortar with ion chelator (MCA) was 30.3%, which is lower than in control mortar (CM). The compressive strength of MCA under seawater for 90 days was 34.4 MPa, while that of CM was 27.4 MPa. The ion chelator enhanced the self-healing capability of pre-damaged mortar remarkably. After 28 days seawater immersion, compressive strength recovery rate of MCA under fresh-water and seawater was 94% and 80%, respectively. And the maximum crack width completely healed in MCA under seawater is up to 350 μm, while around 240 μm in MCA under fresh-water. XRD analysis revealed that the crack-healing products in MCA under seawater immersion were magnesium hydroxide and calcium carbonate.

The increasing reclaimed asphalt pavement mixture causes environmental pollution and a waste of resource, which could be resolved by the asphalt recycling technology. In this paper, corn oil, waste engine oil, vacuum stream oil and cashew shell oil are used for rejuvenating aged SBS modified asphalt (ASMA), and the effect of composition, structure and thermal-oxidative stability of recycling agents on the early and long-term performance of rejuvenated binder are thoroughly investigated. The results indicate cashew shell oil with nut phenol derivatives has the best rejuvenating effect on ASMA, corn oil containing aliphatic hydrocarbons is more conducive to improving the low temperature performance of rejuvenated ASMA, and vacuum stream oil containing nonpolar alkane compound shows the worst regeneration effect. Meanwhile, simultaneous thermal analysis reveals nonpolar aliphatic hydrocarbons vacuum stream oil has the poorest thermal stability for its lowest initial decomposition temperature 146 °C, while initial decomposition temperature of cashew shell oil and corn oil are all over 200 °C. The changes of physical and rheological properties of cashew shell oil rejuvenated ASMA after aging are much smaller than that of others, which indicates cashew shell oil with excellent thermal-oxidative stability is more conductive to inhibiting the transition from viscosity to elasticity of rejuvenated binder in the aging process. While vacuum stream oil rejuvenated ASMA shows the most serious aging degree, suggesting the poor thermal-oxidative stability of recycling agents has adverse effects on the anti-aging properties of rejuvenated binder. Infrared spectrum analysis indicates the aging index growth rate of cashew shell oil rejuvenated ASMA is the smallest, also demonstrating the best aging resistance of cashew shell oil rejuvenated ASMA. The correlation coefficients between sulfoxide index and physical-rheological properties are almost all higher than 0.90, while that between sulfoxide index and physical-rheological properties are lower than 0.71, therefore sulfoxide index can be a better indicator for estimating the physical-rheological properties of rejuvenated SBS modified bitumen in the service.

Ion chelator is a novel crystalline admixture which can promote the self-healing of cracks in cement-based materials. In this paper, the self-healing capability of the surface and internal cracks of mortars with ion chelator of different age were investigated by the change of crack width, water permeability, recovery of compressive strength and X-ray computer tomography test. The results indicated that the surface crack up to 0.4 mm on the mortars with 0.5 wt% ion chelator pre-cracked at different age can be repaired after standard curing for 30 d. According to the water permeability test, the mortars with ion chelator pre-cracked at 3 d and 28 d have excellent self-healing ability for internal cracks, and the relative permeability coefficient of the mortars with 0.5 wt% ion chelator decreases most significantly. The compressive strength recovery test of mortars shows that ion chelator can promote the self-healing of internal cracks within the mortars. After curing for 56 d, the compressive strength recovery ratio of the mortars with 0.5 wt% ion chelator pre-loaded at 28 d reached 99.5%. And the X-ray computer tomography displayed that the self-healing process of cracks in mortars was from outside to inside.

The regeneration and utilization of reclaimed SBS modified bitumen require a high mixing and paving temperature, which result in a large of energy consumption and serious environment pollution. To reduce the mixing and paving temperature, polyethylene wax and active wax were selected to modify rejuvenated SBS modified bitumen, and their influences on the viscosity-temperature characteristics, physical and rheological properties of rejuvenated binder were thoroughly investigated in this research. The results indicate that active wax with epoxy terminal group shows a better performance on reducing the mixing and paving temperature of rejuvenated binder as compared with polyethylene wax. Meanwhile active wax modified rejuvenated binder shows the lowest flow activation energy 79.78 kJ/mol, indicating active wax is more helpful to improve the temperature sensitivity of rejuvenated binder at high temperature. Differential scanning calorimetry analysis shows the melting enthalpy of active wax is larger than that of polyethylene wax and polyethylene wax is easier to crystallize and solidify. These two warm additives all can improve the rutting resistance of rejuvenated binder. However, the cracking resistance of rejuvenated binder seriously decreases with the addition of polyethylene wax. While active wax could react with the active groups in rejuvenated binder that can inhibit the transition from viscosity to elasticity of rejuvenated binder and retain its excellent low-temperature performance more effectively as compared with polyethylene wax.

Taurine, an intracellular osmolyte whose body pool size is adaptively regulated by the kidney, is required for normal renal development. Overexpression of the p53 tumor suppressor gene in p53 transgenic mice results in renal malformation, suggesting that altered expression of certain p53 target gene(s) involved in renal development may be responsible. This study shows that the taurine transporter gene (TauT) is a transcriptional target of p53. Expression of TauT was decreased after activation of p53 by doxorubicin, a DNA-damaging drug, in 293 and NRK-52E renal cells. TauT promoter activity was decreased 5-10-fold by cotransfection of a full-length TauT promoter-reporter construct with p53, which was reversed by cotransfection with a mutant p53 (p53-281). Electrophoretic mobility shift assays using nuclear extracts from p53-expressing (10)1val cells showed a putative p53-binding site in the TauT promoter region, which bound to the p53 in electrophoretic mobility shift assays. Mutation of this p53 consensus sequence abolished binding of p53. These results demonstrate that TauT may represent a downstream target gene of p53 that could link the roles of p53 in renal development and apoptosis.

NaCl-dependent taurine transporter (pNCT) activity of MDCK cells (Madin-Darby canine kidney) is up- or down-regulated by medium taurine manipulation. In this study we found that the abundance of pNCT mRNA was up- or down-regulated after cells were incubated in media containing 0 microM taurine or 500 microM taurine for 24 h. Down-regulation was observed after 12 h exposure to high taurine (500 microM) and mRNA abundance was appreciably reduced after 72 h exposure. Nuclear run-off assays show that the gene for pNCT is induced at the transcriptional level by taurine. Addition of cycloheximide blocked the adaptive response and reduced transcription of pNCT mRNA in MDCK cells. Cycloheximide had virtually no effect on pNCT mRNA stability, suggesting that ongoing protein synthesis is required for adaptive regulation of pNCT gene transcription.

The purpose of this study is to investigate the effect of taurine on the human fetal brain cells proliferation with the method of pure cerebral neuronal culture free of glial cells, grown in a serum-free environment. We found that taurine was necessary for neuronal survival, neurite extension. Taurine, on the other hand, has the trophic effect on the human fetal brain cells proliferation determined by [ 3 H]-thymidine incorporation. These results establish taurine as a putative human fetal brain neurontrophic factor in the process of human brain development.