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Using Martian resource to construct a site on Mars is a superior choice to instead of transporting all the construction materials from Earth to the Mas with incredibly high cost. This study proposes a developed Martian concrete composed of sulfur and magnetite, heated by microwave to meet the energy-poor environment on Mars. A lattice Boltzmann model is developed to determine the optimal microwave power and heating time for Martian concrete casting. The compressive strength and microstructure of Martian concrete casted by microwave are measured by test. Finally, a 3D printed device is conceived to prepare Martian concrete and the four-layered specimen is casted to simulate the 3D print process. The results indicate that the compressive strength of Martian concrete casted by microwave can reach 1.78 kgf/mm2 (17.44 MPa) on earth, which is corresponding to 4.62 kgf/mm2 on Mars. Since the heating rate of magnetite under microwave is very high, if possible, the low microwave power and long heating time should be chosen to reduce the temperature gradient in matrix and reduce the possibility of sulfur matrix boiling. In addition, the strength of four-layered (simulated 3D printed) Martian concrete can reach 1.21 kgf/mm2 (11.86 MPa) on earth, which is corresponding to 3.15 kgf/mm2 on Mars.

Engineered cementitious composite (ECC) is a group of ultra-ductile fibre-reinforced cementitious composites, characterised by high ductility and moderate content of short discontinuous fibre. The unique tensile strain-hardening behaviour of ECC results from a deliberate design based on the understanding of micromechanics between fibre, matrix, and fibre–matrix interface. To investigate the effect of fibre properties on the tensile behaviour of ECCs is, therefore, the key to understanding the composite mechanical behaviour of ECCs. This paper presents a study on the fibre-bridging behaviour and composite mechanical properties of ECCs with three types of fibres, including oil-coated polyvinyl alcohol (PVA) fibre, untreated PVA fibre, and polypropylene (PP) fibre. The experimental result reveals that various fibres with different properties result in difference in the fibre-bridging behaviour and composite mechanical properties of ECCs. The difference in the composite mechanical properties of ECCs with different fibres was interpreted by analysing the fibre-bridging behaviour.

Two new abietane diterpenoids (1,2), along with five known diterpenoids (3–7), were first isolated and purified from the stems of Clerodendrum bracteatum. The structures of the new compounds were established by extensive analysis of mass spectrometric and 1-D, 2-D NMR spectroscopic data. Their antioxidant activities were determined on DPPH radical scavenging and ABTS. The in vitro cytotoxic activities of the compounds were evaluated against the HL-60 and A549 cell lines by the MTT method.

The impact of ultraviolet-B (UV-B) treatment on oxidative stress, cold damage, and antioxidant enzymes and the role of the UV-B photoreceptor SlUVR8 in tomatoes during cold storage were investigated. Mature-green tomato fruit were irradiated with 1, 10, or 100 μmol m−2 s-1 UV-B for 1, 3, or 6 h respectively before cold-storage. The chilling injury index (CI), H2O2, O2 −, ion leakage, and malondialdehyde (MDA) content in tomatoes stored at 2 ℃ increased during storage, while irradiation with 10 μmol m−2 s-1 UV-B for 3 h before storage significantly reduced H2O2 and O2 −, membrane damage and chilling injury. Expression of CuZuSOD, FeSOD and CAT1 and the activities of their encoded enzymes superoxide dismutase (SOD) and catalase (CAT) were markedly raised in UV-B-pre-irradiated tomatoes and correlated significantly with the reductions in H2O2, O2 −, ion leakage, MDA, and CI, which suggested that UV-B pre-irradiation might exert its effects by activating the antioxidant enzymes. Silencing SlUVR8 dramatically counteracted the UV-B-mediated effects on enzyme expression while the contents of H2O2, O2 −, ion leakage, MDA, together with the CI in SlUVR8-silenced tomatoes were significantly higher. The data showed that silencing of SlUVR8 not only suppressed UV-B-activated SOD and CAT expression, but also prevented UV-B-alleviated oxidative stress and chilling injury. The findings indicated that SlUVR8 was required for UV-B-induced cold tolerance in tomato fruit and demonstrated that UV-B irradiation before cold storage activated SOD and CAT in an SlUVR8-dependent manner.

Triethanolamine (TEA) is known as a widely-used cement additive for regulating setting time, hydration process and mechanical strength. However, the working mechanism of TEA on blended cement with various kinds of minerals, has not yet thoroughly explored. This invesitigation focused on effects of TEA on the strength enhancement and hydration properties of the blended cementitious materials, containing fly ash, slag, limestone. Hydration heat evolution of the composite binder was studied by isothermal calorimetry. Pore size distribution was analyzed through mercury injection porosimetry (MIP), and the evolution of hydration products in the function of TEA was investigated by X-ray diffractometry (XRD), differential thermal analysis (DTA) and thermogravimetric analysis (TG). Microstructure and composition characteristics of hydration products were studied through scanning electron microscopy (SEM) equiped with energy dispersive X-ray spectroscopy (EDX). Results showed that strength enhancement effect of TEA varied when the component and proportion of cementitious materials altered. Containing 30% fly ash and 10% limestone, the composite binder got the optimal strength-enhancing effect to nearly 15%. When containing 30% slag and 10% fly ash, the composite binder obtained the worst strength-enhancing effect with about 5%. The addition of TEA prolonged the induction period, and enhanced the formation of AFt. With high aluminate glass phases, fly ash was vulnerable to be influenced by the complexation of TEA, and hence the pozzolanic reaction of fly ash was accelerated significantly, resulting in reduced content of Ca(OH) 2 (CH) as well as increased production of hydrates. Limestone participated to accelerate the hydration of C3A, and provided microcrystals for the growth of hydrates. Slag was mainly composed of high calcium glass phases and was rarely impacted by the complexation of TEA. The findings would gain a comprehensive insight of TEA in affecting the hydration process of blended materials, and would provide expedient information on the technique to control the hydration progress of composite binder.

Background The influence of epicatechin (EC) on the physicochemical properties and digestibility changes of porcine myofibrillar protein (MP) under oxidative stress during refrigerated storage was investigated. Results The incubation of MP suspensions (20 mg mL-1 in piperazine-N,N'-bis(2-ethanesulfonic acid) buffer, with 0.6 mol L-1 sodium chloride, pH 6.25) at 4 °C for 24 h under an iron-catalyzed hydroxyl radical generating system (Fenton reaction) promoted the formation of thiobarbituric acid reactive substances and protein carbonyls, which was attenuated by EC (5, 50, and 100 μmol g-1 protein). Reduced protein sulfhydryl content, tryptophan fluorescence, protein solubility, as well as increased surface hydrophobicity were found by the co-incubation of EC. Analysis by scanning electron microscopy revealed increased protein aggregation and fragments in oxidized MP, which were further enhanced by the addition of EC. However, the protein digestibility of MP was not affected. Conclusion EC was demonstrated to be effective in alleviating lipid oxidation and protein carbonylation in MP under oxidative stress. Additionally, the physicochemical and digestibility changes accompanying the incorporation of EC was complicated due to the possible phenol-protein interactions. An in-depth understanding of protein physicochemical and digestibility changes will be helpful in the application of polyphenolic compounds as antioxidants in low-temperature-processed muscle foods. © 2020 Society of Chemical Industry.

The objective of this study was to investigate the antibacterial activity and potential mechanism of alkyl gallates against Escherichia coli and Staphylococcus aureus. Results show that the length of the alkyl chain plays a pivotal role in eliciting the activity and octyl gallate (OG) exerted excellent bactericidal activity through a multiple bactericidal mechanism. OG functions against both bacteria through damaging bacterial cell wall integrity, permeating into cells and then interacting with DNA, as well as disturbing the activity of the respiratory electron transport chain to induce a high-level toxic ROS (hydroxyl radicals) generation and up-regulation of the ROS genes. Also, electrospun nanofibers with OG have unique superiorities for maintaining the freshness of the icefish (4 °C). This research not only provides a more in-depth understanding of the interaction between OG and microorganisms but also highlights the great promise of using OG as a safe multi-functionalized food additive for food preservations.

Bioassay-guided fractionation of the culture extract of Pestalotiopsis adusta, an endophytic fungus isolated from the medicinal plant Clerodendrum canescens, led to the isolation of one new, (10S)-12,16-epoxy-17(15→16)-abeo-3,5,8,12,15-abietapentaen-2,7,11,14-tetraone (1), and four known diterpenoids, teuvincenone F (2), uncinatone (3), coleon U (4), coleon U-12-methyl ether (5). These structures were identified by using spectroscopic methods, including UV, MS, 1D and 2D NMR experiments. This is the first report of these compounds being isolated from a Pestalotiopsis species. The cytotoxic activities of the compounds were evaluated, and compounds 1 and 3 demonstrated cytotoxic activities against the HL-60 tumour cell line (IC50 ＜ 20 μM).

Auxin is involved in different aspects of plant growth and development by regulating the expression of auxin-responsive family genes. As one of the three major auxin-responsive families, GH3 (Gretchen Hagen3) genes participate in auxin homeostasis by catalyzing auxin conjugation and bounding free indole-3-acetic acid (IAA) to amino acids. However, how GH3 genes function in responses to abiotic stresses and various hormones in maize is largely unknown. Here, the latest updated maize (Zea mays L.) reference genome sequence was used to characterize and analyze the ZmGH3 family genes from maize. The results showed that 13 ZmGH3 genes were mapped on five maize chromosomes (total 10 chromosomes). Highly diversified gene structures and tissue-specific expression patterns suggested the possibility of function diversification for these genes in response to environmental stresses and hormone stimuli. The expression patterns of ZmGH3 genes are responsive to several abiotic stresses (salt, drought and cadmium) and major stress-related hormones (abscisic acid, salicylic acid and jasmonic acid). Various environmental factors suppress auxin free IAA contents in maize roots suggesting that these abiotic stresses and hormones might alter GH3-mediated auxin levels. The responsiveness of ZmGH3 genes to a wide range of abiotic stresses and stress-related hormones suggested that ZmGH3s are involved in maize tolerance to environmental stresses.

Titanium dioxide (TiO2) nanoparticles have been incorporated in cementitious composites to achieve photocatalytic (PC) functions such as self-cleaning and air purifying functions. This study experimentally investigates the effect of TiO2 nanoparticles and fly ash on the nitrogen oxides (NOx) abatement rate and efficiency of Engineered Cementitious Composites (ECC) that has retained strain-hardening properties and tensile ductility. Emphasis is placed on understanding the fundamental mechanisms through research on the microstructures and chemical environment of the composite material. A first-order chemical reaction model is applied to analyze the PC reaction rate and residual NOx concentration. Test results indicate that the PC reaction rate and efficiency increase with the TiO2 content from 0 to 5%, and the fly ash to cement ratio from 0 to 2.2. Using the low-calcium fly ash further increases the PC reaction rate and efficiency. The microstructure change originated from different fly ash contents and types are closely related to PC efficiency changes. This study advances the fundamental knowledge for engineering the cementitious composites to achieve the optimal PC functions.

Soluble high refractive index polyimides have extensive applications in optical devices due to their ease of processing and versatility. In this work, selenide-containing polyimides were designed and synthesized via amine-dianhydride polycondensation. Two selenide containing diamines, e.g. bis(3-trifluoromethyl-4-aminophenyl)selenide (BTFAPS) and bis(4-aminophenyl)selenide (BAPS) were reacted with 4,4′-(Hexafluoroisopropylidene)diphthalic anhydride (6FDA) for the preparation of selenide containing polyimides. Comparison with its oxygen and sulfur counterparts, the selenide-containing PIs have better solubility, higher refractive index, and can bring redox responsiveness. This is due to the trifluoromethyl base, which possesses a large free volume, and the selenium element, which has a higher molar refraction and redox activities than even sulfur. Various techniques, such as nuclear magnetic resonance, gel permeation chromatography, Fourier transformed infrared spectroscopy and wide angle X-ray diffraction were used for characterizing the polymers structure. Differential scanning calorimetry, thermogravimetric analysis, ultraviolet-visible spectroscopy, spectroscopic ellipsometry and X-ray photoelectron spectroscopy were used to characterize the properties of the polymers.

Two new abietane diterpenoids, named 17-hydroxyteuvincenone G (1) and 17-hydroxyteuvincen-5(6)-enone G (2), together with four known diterpenoids, were isolated from the stems of Clerodendrum kaichianum P. S. Hsu. Their structures were elucidated by extensive NMR and MS analyses, and by comparison with literature data. The new compounds showed significant cytotoxicities against the HL-60 and A-549 tumor cell lines.

Epidemiological studies give evidence that high dietary intake of cruciferous vegetables has been associated with lower risk of cancer, this activity due to their content in glucosinolates (GL), which upon myrosinase hydrolysis release the corresponding isothiocyanates (ITCs). In this study, the isothiocyanates contents and the anticancer activity of ethyl acetate extracts from three kinds of Chinese Brassica vegetable seeds have been examined and analyzed. A correlation was found between the potency of anticancer activity and the amount of isothiocyanates in their extracts. Extracts followed by GC–MS analysis revealed that 3-BITC (3-butenyl isothiocyanate) was mainly found in Chinese kale contained 77.58 ± 7.28 mg/g (dry weight); AITC (allyl isothiocyanate), 3-BITC and iberverin were the predominant isothiocyanates in Oxheart cabbage contained 33.57 ± 3.94, 26.50 ± 1.92 and 22.77 ± 0.00 mg/g, respectively; 3-BITC and sulforaphane were found as the major isothiocyanates in broccoli contained 138.52 ± 3.42 and 49.77 ± 0.18 mg/g, respectively. The amount of total isothiocyanates in broccoli was twice higher than that in other two species. The anticancer activity of broccoli was the highest, and the IC50 value of the extract inhibiting on the growth of A549, LAC, HELA and HepG2 were 14.38 ± 0.35, 10.38 ± 0.34, 19.45 ± 1.72 and 26.75 ± 0.82 mg/g, respectively. The extracts of Chinese Brassica vegetable seeds have the potential in inducing cancer cells apoptosis by morphology observation. The results of this study got a new kind of Brassica vegetable seeds that could produce high content of isothiocyanates, which is important to preparation of anticancer food additives.

An investigation of the flavonoids in Daphniphyllum angustifolium Hutch . resulted in the identification of a new biflavonoid, 5,7,4′-trihydroxyflavan (2α→O→7, 4α→8) kaempferol ( 1 ), together with five known flavonoids . Their structures were determined by spectroscopic method.

High-speed counter-current chromatography (HSCCC) was successfully used for the separation of abietane-type diterpenoids from the medicinal plant C. kaichianum, which were not separated in our previous study using preparative HPLC. The HSCCC separation employed the lower phases of n-hexane–ethyl acetate–methanol–water (HEMW) 4:5:4:5 and HEMW 4:5:5:4 as the mobile phase for stepwise elution while the upper phase of HEMW 4:5:4:5 was used as the stationary phase. HSCCC separation yielded 90.5 mg of compound 1(kaichianone A), 137.7 mg of compound 2 (kaichianone B), 125.0 mg of compound 3 (teuvincenone E), and 227.6 mg of compound 4 (taxusabietane A) with purities of 95.3%, 97.2%, 97.8%, and 98.6%, respectively, as determined by HPLC. Compounds 1–2 are two new abietane-type diterpenoids while Compounds 3–4 are known abietane-type diterpenoids, analyzed by ESIMS and NMR data. The results demonstrated that HSCCC can be an excellent alternative for other separation methods. The two new compounds showed significant cytotoxicity against ileocecal carcinoma HCT-8 and breast adenocarcinoma MCF-7 cells. High-speed counter-current chromatography (HSCCC) was successfully used for the separation of abietane-type diterpenoids from the medicinal plant C. kaichianum, which were not separated in our previous study using preparative HPLC.

The effects of UV-B irradiation on reactive oxygen species (ROS) levels, antioxidant compound contents, antioxidative enzyme activities, and oxidative damage of cold-stored mangoes were examined. Superoxide anion production rate, hydrogen peroxide concentration, ion leakage level and malondialdehyde content of the cold-stored fruit preradiated with 5 KJ m(-2) UV-B for 4 h were significantly decreased as compared with control fruit. The activities of ROS generating enzymes remained unchanged in UV-B-irradiated mangoes as compared to the control, but superoxide dismutase and catalase activities, ascorbate and polyphenol contents and antioxidant capacities of the cold-stored mangoes were significantly enhanced by UV-B. The UV-B-enhanced antioxidant compounds and antioxidative enzymes were highly correlated with the reduced-ROS levels in UV-B-irradiated mangoes. The data indicated that a short UV-B exposure reduced oxidative stress and alleviated oxidative damage of the cold-stored mangoes by triggering both enzymatic and nonenzymatic antioxidant systems although ROS generation in the fruit was not affected.

Cotton (Gossypium spp.) is an important economic crop and there is obvious heterosis in cotton, fertility has played an important role in this heterosis. However, the genes that exhibit critical roles in anther development and fertility are not well understood. Here, we report an acyl-CoA N-acyltransferase (EC2.3; GhACNAT) that plays a key role in anther development and fertility. Suppression of GhACNAT by virus-induced gene silencing in transgenic cotton (G. hirsutum L. cv. C312) resulted in indehiscent anthers that were full of pollen, diminished filaments and stamens and plant sterility. We found GhACNAT was involved in lipid metabolism and jasmonic acid (JA) biosynthesis. The genes differentially expressed in GhACNAT-silenced plants and C312 were mainly involved in catalytic activity and transcription regulator activity in lipid metabolism. In GhACNAT-silenced plants, the expression levels of genes involved in lipid metabolism and jasmonic acid biosynthesis were significantly changed, the amount of JA in leaves and reproductive organs was significantly decreased compared with the amounts in C312. Treatments with exogenous methyl jasmonate rescued anther dehiscence and pollen release in GhACNAT-silenced plants and caused self-fertility. The GhACNAT gene may play an important role in controlling cotton fertility by regulating the pathways of lipid synthesis and JA biogenesis.

A new abietane diterpenoid, (3S,16R)-12,16-epoxy-3,6,11,14,17-pentahydroxy-17(15 → 16)-abeo-5,8,11,13-abietatetraen-7-one (1), was isolated from the stems of Clerodendrum kaichianum Hsu, together with four known diterpenoids. The structures of the isolated compounds were assigned on the basis of their NMR spectra including 2D NMR techniques such as COSY, HMQC, and HMBC experiments, and were compared with those of the literature data. This new compound showed significant cytotoxicity against the HL-60 and A-549 tumor cell lines.

Bioassay-guided isolation studies of the extract of Clerodendrum kaichianum Hsu., a new rearranged abietane diterpene and five known diterpene compounds were isolated by various chromatography methods. Their structures were identified by means of spectroscopic methods, including 1D- and 2D-NMR spectroscopy, as (16 R)-12,16-epoxy-11,14,17-trihydroxy-17(15→16)- abeo-8,11,13-abietatrien-7-one (1), villosin A (2), salvinolone (3), 14-deoxyloleon U (4), 5,6-dehydrosugiol (5), and coleon U (6). Compounds 1, 2, 3, and 5 are reported for the first time for this genus. Compounds 1, 2, and 6 demonstrated potent cytotoxic activities against the HL-60 tumor cell line.

A new abietane diterpenoid has been isolated from Clerodendrum kaichianum Hsu and characterised as 11-methoxyl-12,14-dihydroxy-13-(2-hydroxypropyl)-3,5,8,11,13-abietapentaen-7-one. Its structure was established by spectroscopic analysis, including 2D NMR.