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Abstract: (−)-Epigallocatechin-3-O-gallate (EGCG) acetylated derivatives were prepared by lipase catalyzed acylation of EGCG with vinyl acetate to improve its lipophilicity and expand its application in lipophilic media. The immobilized lipase, Lipozyme RM IM, was found to be the optimum catalyst. The optimized conditions were as follows, 1:1 of the molar ratio of EGCG to vinyl acetate, 2.0% (w/w of both substrates) of enzyme amount, and 84.5% conversion was obtained after 8h reaction at 40°C in acetonitrile. The presence of mono-, di- and tri-acetylated derivatives in acetylated EGCG were confirmed by LC–MS–MS and the tri-acetylated EGCG was identified as 5′,3″,5″-3-O-acetyl-EGCG by NMR. Their enhanced lipophilicity was confirmed by octanol–water partition coefficient. The antioxidant activity of the acetylated EGCG derivatives were superior to butylated hydroxytoluene (BHT), tert-butyl hydroquinone (TBHQ) and EGCG as determined by peroxide values (POVs) in sunflower oil as well as by the p-anisidine method. Acetylated EGCG exhibited the highest 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (IC50 of 0.09mg/mL) compared to EGCG, BHT and TBHQ. Acetylated EGCG might be used as a potent antioxidant for controlling oxidation of sunflower oil. [Copyright &y& Elsevier]

We have applied 57Fe nuclear resonance vibrational spectroscopy (NRVS) for the first time to study the dynamics of Fe centers in Iron-sulfur protein crystals, including oxidized wild type rubredoxin crystals from Pyrococcus furiosus, and the MoFe protein of nitrogenase from Azotobacter vinelandii. Thanks to the NRVS selection rule, selectively probed vibrational modes have been observed in both oriented rubredoxin and MoFe protein crystals. The NRVS work was complemented by extended X-ray absorption fine structure spectroscopy (EXAFS) measurements on oxidized wild type rubredoxin crystals from Pyrococcus furiosus. The EXAFS spectra revealed the Fe-S bond length difference in oxidized Pf Rd protein, which is qualitatively consistent with the crystal structure. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we presented a new aptasensor for fumonisin B1 (FB1) based on fluorescence resonance energy transfer (FRET) between NaYF4: Yb, Ho upconversion fluorescent nanoparticles (UCNPs) and gold nanoparticles (AuNPs). The quenchers (AuNPs) were attached to the 5′ end of the molecular beacon (MB), and the donors (UCNPs) were attached to the 3′ end of the MB. In the absence of target DNA (DNA complementary to FB1 aptamers), the energy donors and acceptors were placed in close proximity, leading to quenching of the fluorescence of the UCNPs. Due to the combination of FB1 and FB1-specific aptamers, this caused some complementary DNA dissociating from the magnetic nanoparticles (MNPs). In the presence of the complementary DNA, the MBs underwent spontaneous conformational change and caused the UCNPs and AuNPs to detach from each other, resulting in restoration of the upconversion fluorescence. Therefore, the fluorescence of UCNPs was restored in a FB1 concentration-dependent manner, which was the basis of the FB1 quantification. The aptasensors showed a linear relationship from 0.01 to 100ngmL−1 for FB1 with a detection limit of 0.01ngmL−1 in an aqueous buffer. As a practical application, the aptasensor was used to monitor FB1 levels in naturally contaminated maize samples. The results were consistent with that of a classic ELISA method, indicating that the UCNPs–FRET aptasensor, which benefited from the near infrared excitation of NaYF4: Yb, Ho UCNPs, was effective for directly sensing FB1 in foodstuff samples without optical interference. This work also created the opportunity to develop aptasensors for other targets using this FRET system. [Copyright &y& Elsevier]

Abstract: Energy research is to a large extent materials research, encompassing the physics and chemistry of materials, including their synthesis, processing toward components and design toward architectures, allowing for their functionality as energy devices, extending toward their operation parameters and environment, including also their degradation, limited life, ultimate failure and potential recycling. In all these stages, X-ray and electron spectroscopy are helpful methods for analysis, characterization and diagnostics for the engineer and for the researcher working in basic science. This paper gives a short overview of experiments with X-ray and electron spectroscopy for solar energy and water splitting materials and addresses also the issue of solar fuel, a relatively new topic in energy research. The featured systems are iron oxide and tungsten oxide as photoanodes, and hydrogenases as molecular systems. We present surface and sub-surface studies with ambient pressure XPS and hard X-ray XPS, resonant photoemission, light induced effects in resonant photoemission experiments and a photo-electrochemical in situ/operando NEXAFS experiment in a liquid cell, and nuclear resonant vibrational spectroscopy (NRVS). [Copyright &y& Elsevier]

Abstract: Aims: The objective of this study was to examine the involvement of endogenous opioid peptides and opioid receptor (OR) subtypes in the cardioprotective effect of adaptation to chronic hypoxia in rats. Main methods: Rats were exposed to continuous normobaric hypoxia (CNH; 12% oxygen) for 3 weeks. Myocardial ischemia was induced by 20-min coronary artery occlusion followed by 3-h reperfusion in anesthetized open-chest animals. Various OR antagonists were administered to rats prior to ischemia. The size of myocardial infarction and the incidence of ischemic ventricular arrhythmias were assessed. Myocardial and plasma concentrations of opioid peptides (met-enkephalin, β-endorphin, and endomorphins) were determined. Key findings: Adaptation to CNH significantly increased myocardial and plasma concentrations of opioids, potentiated their further elevation by ischemia/reperfusion, and reduced myocardial infarct size, but it did not affect the incidence of ischemic arrhythmias. The infarct size-limiting effect of CNH was abolished by OR antagonists naltrexone (non-selective), naloxone methiodide (non-selective peripherally acting), TIPP[ψ] (δ-OR), naltriben (δ2-OR), or CTAP (μ-OR), while BNTX (δ1-OR) and nor-binaltorphimine (κ-OR) had no effect. Significance: The results suggest that the infarct size-limiting effect afforded by adaptation to CNH is mediated by activation of peripheral δ2- and μ-ORs by elevated levels of endogenous opioid peptides. [Copyright &y& Elsevier]

Highlights: [•] A new method was developed to separate four flavonoids from Rhodiola rosea. [•] The merits of the method were low solvent consumption and no tedious sample pre-treatment. [•] The two of the four flavonoids were separated first time from Rhodiola rosea. [ABSTRACT FROM AUTHOR]

The insoluble peptide aggregates formed by proteolysis are usually discarded by food industries, which results in significant wastage of resources and burden on the related industries. In the present study, insoluble peptide aggregates formed during enzymatic hydrolysis of goat milk casein protein (GCA) were used to prepare goat milk casein nanoparticles (GCP) using a controlled pH-shifting treatment. Next, hydrophobic curcumin (Cur) was embedded in the GCP core, and nano-scale stable hydrophilic particles (GCP-Cur) were successfully prepared. The XRD and FT-TR spectroscopy results showed that the Cur was successfully encapsulated in GCP nanoparticles in an amorphous form, and Cur loading does not cause conformational changes. The morphological results also verified the successful design of the GCP-Cur nanoparticles. Furthermore, the GCP-Cur nanoparticles significantly improved the water solubility, storage stability, in vitro bioaccessibility, and antioxidant activity of Cur. Moreover, the anti-gastric digestion properties of GCP-Cur nanoparticles could control the effective release of Cur from the composite particles into the intestine, and can thus be used as a potential delivery carrier for biologically activity. This research provides theoretical and technical guidance for the development and high-value application of these low-value peptide byproducts. • pH-shifting processes of insoluble goat milk casein aggregates (GCA) were studied. • pH- shifting formation of goat milk casein nanoparticles (GCP) from GCA. • GCP exhibited good thermal storage stability and smaller average particle size. • Curcumin (Cur) was successfully loaded in GCP by controlled pH-shifting processes. • The antioxidant activity, solubility and stability of Cur were improved. [ABSTRACT FROM AUTHOR]

[Display omitted] • EGCG bilosomes were successfully prepared by ethanol injection method. • EGCG niosomes had the highest long-term stability. • EGCG bilosomes had the highest stability in simulated gastrointestinal tract. • EGCG bilosomes can significantly improve the bioavailability of EGCG. Epigallocatechin gallate (EGCG) has a variety of biological activities, but exhibits poor stability and low bioavailability. In this study, EGCG bilosome was prepared and characterized, and its stability during different storage conditions (pH, NaCl concentration, and temperature) and in gastrointestinal fluid was evaluated and compared with liposomes and niosomes. Among them, EGCG niosomes had the highest pH stability, and the existence of sodium cholate reduced the stability of bilosomes in acidic medium. EGCG stability was significantly increased in the presence of salt ions (0–100 mM NaCl) and under different temperatures (25 °C, 37 °C) when delivered as niosomes and bilosomes. Retention rate of EGCG in bilosomes was 71.64 ± 4.05% after incubation in simulated intestinal fluid for 2 h, which was significantly higher than retention rate of EGCG liposomes (24.02 ± 3.95%) and niosomes (55.74 ± 6.85%), thus indicating greater gastrointestinal stability of EGCG bilosomes. Furthermore, bioavailability of EGCG encapsulated in bilosomes was improved by 1.98 times. Overall, these findings indicate that EGCG bilosomes, as a new delivery system, had great potential application as a means to improve stability and bioavailability of EGCG. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Gal-6-sulfurylase from Eucheuma striatum was first purified to homogeneity. [•] Enzymatic treatment improved the gel strength of κ-carrageenan to 1630.2g/cm2. [•] This improvement is due to the cyclization of 3,6-AG by removing sulfate groups. [•] This study provides an eco-friendly method to produce better quality κ-carrageenan. [ABSTRACT FROM AUTHOR]

Abstract: Enrichment of burdock leaf components and the inhibition effect of the obtained 7 burdock leaf fractions on formation of biofilm have been evaluated for the first time. Firstly, burdock leaf fractions were obtained though separation of burdock leaf extracts by macroporous resin column chromatography, and four fractions were obtained, namely, water elution fraction, 20%, 34% and 70% ethanol eluted fractions. It was found that the 20% and 34% ethanol fractions both significantly inhibited the formation of biofilm by Escherichia coli, with IC50 of 1.10 and 1.01 mg/ml, respectively. The 70% ethanol elution fraction exhibited the strongest inhibitory activity against biofilm formation with an IC50 of 0.017 mg/ml. In order to obtain more fractions with higher inhibitory activity, polyamide resin was used to further purify the 34% ethanol elution fraction. The second chromatography separation significant improved the activity of burdock leaf fractions and the IC50 of a new fraction was 0.03 mg/ml. The phenolic contents of the fractions ranged from 7.5 to 369.7 mg/g and there was a high correlation between the anti-biofilm capacity and phenolic contents, except for 70% ethanol fraction. Scanning electron microscopy (SEM) observation showed that there was no biofilm formation for cultures treated with burdock leaf fraction, conforming the significant inhibition activity of burdock leaf fraction against the formation of biofilm. The results suggest that separation and enrichment of the active ingredients could significantly improve the activities of fractions and the obtained burdock leaf fractions provide new alternatives for control of biofilms. [Copyright &y& Elsevier]

Highlights: [•] An ultrasensitive FRET aptasensor was developed for staphylococcal enterotoxin B determination. [•] SEB was recognized by SEB aptamer with high affinity and specificity. [•] The Mn2+ doped NaYF4:Yb/Er UCNPs used as donor to quencher dye (BHQ3) in new FRET. [•] The fluorescence intensity was prominently amplified using an exonuclease-catalyzed target recycling strategy. [Copyright &y& Elsevier]

Phenylpropanoid glycosides are a class of the major bioactive components fromRhodiola rosea. In this study, an efficient method for isolation and purification of four phenylpropanoid glycosides (PPGS) fromRhodiola roseawas established by High-speed Counter-current Chromatography (HSCCC).Rhodiola roseaextract was pre-separated by HPD-200 macro porous resin and polyamide column adsorption chromatography for the enrichment of PPGS and the removal of flavonoid impurities. The enriched PPGS were prepared for subsequent HSCCC. The efficient preparative HSCCC separation and purification of PPGS was developed at a flow rate of 1.5 mL, using a 2-phase solvent system composed of ethyl acetate–butanol–water (1:0.35:1.35, v/v/v) which was selected according to the measurement of partition coefficient (K). By normal HSCCC separation model, 150 mg of the enriched sample was separated, yielding 27.8 mg of compound A, 34.3 mg of compound B, 3.6 mg of compound C, 54.8 mg of compound D, at a purity of 97.4%, 96.8%, 95.2%, and 98.5%, respectively. The purities of target compounds were tested by HPLC and the structure was identified by ESI-MS,1H NMR, and13C. The results demonstrate that HSCCC is a very efficient method for the simultaneous preparative separation of phenylpropanoid glycosides fromRhodiola rosea. [ABSTRACT FROM AUTHOR]

Abstract: Combination of ultraviolet (UV) photolysis with infrared (IR) spectroscopy (or UV/IR for abbreviation) is a powerful tool to study various chemical photoreactions, while cryostat and sample-cell windows define the working ranges for both UV and IR beams. Although diamond window has a very wide transmission range from UV to IR, the extreme cost, the absorptions at 1800–2600cm−1 and other problems prevent it from being the solution for all cases. In this paper, a gas-exchange cryostat was modified to realize a UV/mid-IR experiment at cryogenic temperatures. Several windows (including diamond) were discussed as options. A di-nitrogen iron complex trans-[Fe(DMeOPrPE)2(N2)H][BPh4] [DMeOPrPE=1,2-bis(dimethoxypropylphosphino)ethane] was studied as a real photolysis example. Alternatively, a cold-finger cryostat was modified for UV/far-IR compatible experiments. Non-photolysis samples K5[Mo4O11(R,S-Hhomocit)2]Cl·5H2O (H4homocit=homocitric acid) and [(n-Bu)4N]2[Fe4S4(PPh)4] were studied at cryogenic temperatures. Sample cell windows can also be used as a natural way for choosing photolysis wavelength (in addition to the use of optical filters). [Copyright &y& Elsevier]

Abstract: In order to selectively remove caffeine from green tea, a microwave-enhanced vacuum ice water extraction (MVIE) method was proposed. The effects of MVIE variables including extraction time, microwave power, and solvent to solid radio on the removal yield of caffeine and the loss of total phenolics (TP) from green tea were investigated. The optimized conditions were as follows: solvent (mL) to solid (g) ratio was 10:1, microwave extraction time was 6min, microwave power was 350W and 2.5h of vacuum ice water extraction. The removal yield of caffeine by MVIE was 87.6%, which was significantly higher than that by hot water extraction, indicating a significant improvement of removal efficiency. Moreover, the loss of TP of green tea in the proposed method was much lower than that in the hot water extraction. After decaffeination by MVIE, the removal yield of TP tea was 36.2%, and the content of TP in green tea was still higher than 170mgg−1. Therefore, the proposed microwave-enhanced vacuum ice water extraction was selective, more efficient for the removal of caffeine. The main phenolic compounds of green tea were also determined, and the results indicated that the contents of several catechins were almost not changed in MVIE. This study suggests that MVIE is a new and good alternative for the removal of caffeine from green tea, with a great potential for industrial application. [Copyright &y& Elsevier]

We have used 57Fe nuclear resonance vibrational spectroscopy (NRVS) to study oxidized and reduced forms of the [4Fe-4S] cluster in the D14C variant ferredoxin from Pyroroccusfuriasas (PfD14C Fd). To assist the normal-mode assignments, we conducted NRVS with D14C ferredoxio samples with 36S substituted into the [4Fe-4S] cluster bridging sulfide positions, and a model compound without ligand side chains, (Ph4P)2[Fe4S4Cl4]. Several distinct regions of NRVS intensity are identified, ranging from "protein" and torsional modes below 100 cm', through bending and breathing modes oear 150 cm-1, to strong bands from Fe-S stretching modes between 250 and ∼400 cm-1. The oxidized ferredoxin samples were also investigated by resonance Raman (RR) spectroscopy. We found good agreement between NRVS and RR frequencies, but because of different selection rules, the intensities vasy dramatically between the two types of spectra. The 57Fe partial vibrational densities of states for the oxidized samples were interpreted by normal-mode analysis with optimization of Urey-Bradley force fields for local models of the [4Fe-45] clusters. Full protein model calculations were also conducted using a supplemented CHARMM force field, and these calculations revealed low-frequency modes that may be relevant to - electron transfer with Pf Pd partners. Density functional theory (DFT) calculations complemented these empincal analyses, and DFT was used to estimate the reorganization energy associated with the [Fe4S4]2+/+ redox cycle. Overall, the NRVS technique demonstrates great promise for the observation and quantitative interpretation of the dynamical properties of Fe-S proteins. [ABSTRACT FROM AUTHOR]

A sensitive luminescent bioassay for the detection of ochratoxin A (OTA), a small molecular mycotoxin, was developed using aptamer-conjugated magnetic nanoparticles (MNPs) as the recognition and concentration element and upconversion nanoparticles (UCNPs) as highly sensitive labels. The bioassay system was fabricated by immobilizing aptamer DNA 1 sequence onto the surface of Fe3O4MNPs, which were implemented to capture and concentrate OTA from bulk samples. The aptamer DNA 1 sequence then hybridized with UCNPs modified with DNA 2 sequence, which could dissociate from DNA 1 and result in a decreased luminescent signal when aptamer DNA 1 recognized and bound to target OTA. Under the optimal conditions, the decreased luminescent intensity (ΔI) is proportional to the concentration of OTA in the range of 1 × 10−13to 1 × 10−9g mL−1with a detection limit of 1 × 10−13g mL−1. The proposed method then was successfully applied to measure OTA in naturally contaminated maize samples and validated by a commercially available enzyme-linked immunosorbent assay (ELISA) method. Benefiting from the magnetic separation and concentration effect of MNPs, the high sensitivity of UCNPs, as well as the selectivity and stability of the aptamer, the present upconversion luminescent bioassay offers a promising approach for the screening of small molecular mycotoxins because it is simple, rapid, highly sensitive, specific, does not require sample pre-concentration and lacks interference from autofluorescence of other biomolecules. [ABSTRACT FROM AUTHOR]

Aim: The objective of this study is to disclose the association of polycythemia with lifestyle-related diseases (hypertension, obesity and glucose intolerance) among the three ethnicities in Qinghai, China. Methods: The subjects were 393 elderly people (247 Han, 97 Tibetan and 49 Mongolian) aged 60 years and more living in Qinghai (3000 m a.s.l.) in China. The associated factors with polycythemia were analyzed in the subjects. Excessive polycythemia was defined as hemoglobin concentration over 20 mg/dL. Results: Polycythemia was associated with men, hypoxemia, obesity and high diastolic blood pressure (DBP) in the elderly in Qinghai. Male sex was associated with polycythemia in all ethnicities. Obesity was associated with Han and Tibetan men. Glucose intolerance and activities of daily living were not directly associated with polycythemia after adjustment for sex. There were 7.9% with excessive polycythemia. Independently-associated factors for excessive polycythemia were male sex, body mass index of 25 or more, SpO2 of less than 85%, DBP of 85 mmHg or more and Han ethnicity (vs Tibetan) by multiple logistic regression. Conclusion: There was a close association of polycythemia with diastolic hypertension and obesity in lifestyle-related diseases in high-altitude elderly people. Han people had a higher hemoglobin concentration after adjustment of lifestyle-related diseases compared with Tibetan people. The difference of hemoglobin concentration may be due to Tibetans undergoing a much longer period of adaptation than Han people. Further study is needed to disclose the association between the difference of hypoxic adaptation, lifestyle-related diseases and chronic mountain sickness for their prevention. [ABSTRACT FROM AUTHOR]

Abstract: Three novel zinc coordination polymers (NH4) n [Zn(Hida)Cl2] n (1), [Zn(ida)(H2O)2] n (2), [Zn(Hida)2] n ·4nH2O (3) (H2ida=iminodiacetic acid) and a monomeric complex [Zn(ida)(phen)(H2O)]·2H2O (4) (phen=1,10-phenanthroline) have been synthesized and characterized by X-ray diffraction methods. 1 and 2 form one-dimensional (1-D) chain structures, whereas 3 exhibits a three-dimensional (3-D) diamondoid framework with an open channel. The mononuclear complex 4 is extended into a 3-D supramolecular architecture through hydrogen bonds and π–π stacking. Interestingly, cyclic nonplanar tetrameric water clusters are observed that encapsulated in the 3-D lattice of 4. Based on 1H and 13C NMR observations, there is obvious coordination of complex 2 in solution, while 1 and 3 decompose into free iminodiacetate ligand. Monomer [Zn(ida)(H2O)3] (5) is considered as a possible discrete species from 2. These coordination polymers can serve as good molecular precursors for zinc oxide. [Copyright &y& Elsevier]

Abstract: Rosavin is one of the main bioactive components in Rhodiola rosea L. with known pharmacological effects. In this study, a simple method for preparative separation and purification of rosavin from R. rosea L. was developed with macroporous adsorption resins. The adsorption isotherms and desorption performances of some resins have been determined and compared. Depending on its hydrophobic force, HPD-200 resin, a styrene-divinylbenzene (SDVB) copolymer, offers the best adsorption and desorption properties for rosavin based on the research results, its adsorption data fit best to the Langmuir adsorption model. Dynamic adsorption and desorption was performed on HPD-200 resin packed in a glass column to obtain optimal parameters for the separation of rosavin. The optimum conditions were as follow. The volume, concentration, bed height and flow rate of loading sample were 4 bed volumes (BV), 0.24mg/mL, 30cm and 2 BV/h, respectively, at 25°C; desorption was performed successively with 30% ethanol of 4 bed volumes, 40% ethanol of 2.5 bed volumes and 60% ethanol of 3 bed volumes. After one run treatment with HPD-200, the rosavin content in the product was increased from 0.69% to 11.02% with a recovery of 82.46%. In this case, the process throughout is 1.34grosavin/Ladsorbent/day, solvent usage is 7.14L ethanol/g rosavin. The simple purification scheme avoids toxic organic solvent and thus, increases the safety of the process with a potential industrial application prospect. [Copyright &y& Elsevier]

• Model community-level energy by combining GIS, simulation, and data-driven approaches. • Propose a GIS-based urban building energy modeling method with low computational cost. • Generate various prototype buildings through two-stage clustering process to describe buildings' diversity. • Integrate urban building energy modeling with global sensitivity analysis to discovery urban planning factors. • Identify FAR and BCR as the most influential factors affecting communities' energy use. The residential sector accounts for an increasing amount of global energy use with continued urbanization. Residential energy-informed urban planning offers an economical and easy-to-operate approach to achieve more efficient urban energy utilization. However, quantifying the interactions between residential energy and urban planning remains an open challenge. This study proposes a holistic approach integrating GIS techniques, building energy modeling, and a global sensitivity analysis to prioritize eight key urban planning factors on the community energy performance based on a building energy dataset. The dataset, including urban planning and building information, was first established using GIS techniques and validated using survey data. The residential energy performance model at the community scale was developed using the clustering tree structure of residential building prototypes and building performance simulations. A combined data-driven and global sensitivity analysis approach was further applied to prioritize the impacts of eight vital urban planning factors on energy use intensity and peak load intensity. A case study of 1963 communities in Shanghai revealed that, for the energy performance of residential communities, the floor area ratio and building coverage ratio are the most influential factors, followed by the maximum height and high-rise proportion having a relatively low impact but higher than other factors. Overall, the proposed holistic approach generates robust insights into urban-scale residential energy performance, which can effectively inform urban planners to achieve more energy-efficient regulatory planning. [ABSTRACT FROM AUTHOR]

• Three types of PW additives with different M w were compared in this paper. • A good correlation was found between M w and the modified effects of PW additives. • The moisture susceptibility of PW modified mix was evaluated by a new parameter SSR. • OPW showed the best modifying performance due to its uniform microstructure. This study aims at investigating the influence of polyethylene wax (PW) additives on the performance of modified asphalt binders and mixtures. Three types of PW additives, including low density wax (LDPW), high density wax (HDPW), and oxidized polyethylene wax (OPW) were selected with different molecular weight (M w). Fischer-Tropsch wax (FTW) and Montan wax (MW) additives were also selected for comparison. Then, several laboratory tests were conducted, including performance grade test, storage ability test, viscosity test, workability test, wheel tracking test, Hamburg wheel tracking device test (HWTD), tensile strength ratio (TSR) test, bending beam test and semi-circular bending (SCB) test. Besides, the fluorescence microscopy test was conducted to investigate the modifying mechanism of different wax additives. Results indicate that, almost all tested wax additives improve the high temperature stability and moisture resistance capacity of the asphalt mixture, while reduce the low temperature stability. As the M w increases, the rational viscosity of the asphalt binder, the moisture resistance capacity and low temperature stability of PW modified asphalt mixture increases, while the storage stability decreases. PW additives perform better in low temperature cracking resistance capacity than AMW and FTW. OPW has the best modifying performance among all selected PW additives due to the uniform microstructure. [ABSTRACT FROM AUTHOR]

Tannic acid (TA) can strongly interact with proteins to improve the stability of protein-based nanoparticles. In the present study, the complexation of TA with bovine lactoferrin (LF) was investigated at pH 6.0. The size and turbidity of the LF-TA complexes did not change significantly until the LF/TA molar ratio was over a critical value of 1:8. Zeta potential of LF-TA was gradually negative as the TA content increased, indicating that there were electrostatic interactions between LF and TA. The circular dichroism (CD) spectroscopy confirmed that TA could further reduce the α-helix and increase the β-sheet content of LF significantly, resulting in a more compact structure of LF. The fluorescence spectra revealed that the interaction between LF and TA caused intramolecular quenching of LF, and the values of K sv increased with temperature, indicating that static quenching was involved in the interaction between LF and TA. Thermodynamic parameters indicated that the reaction between LF and TA proceed spontaneously, and hydrophobic interactions were the major interaction force. Molecular docking suggested that the binding site of TA and LF was in the inter-leaf region where the two lobes were connected by a spiral. Besides, the proteolytic digestion experiments testified that the addition of TA could reduce the digestibility of LF. Information derived from this work suggests that the addition of TA in LF systems could improve the digestive stability of bio-complex for oral delivery of functional constituents. [Display omitted] • Interaction between bovine lactoferrin (LF) and tannic acid (TA) was analyzed. • The interaction between LF and TA led to a more compact structure of LF. • Hydrophobic interaction was predominant in LF-TA complex. • The interaction between LF and TA reduced the digestibility of LF. [ABSTRACT FROM AUTHOR]

Summary: Enhancers can regulate designate promoters over long distances by forming chromatin loops. Whether chromatin loops are lost or reconfigured during gene repression is largely unexplored. We examined the chromosome conformation of the Kit gene that is expressed during early erythropoiesis but is downregulated upon cell maturation. Kit expression is controlled by sequential occupancy of two GATA family transcription factors. In immature cells, a distal enhancer bound by GATA-2 is in physical proximity with the active Kit promoter. Upon cell maturation, GATA-1 displaces GATA-2 and triggers a loss of the enhancer/promoter interaction. Moreover, GATA-1 reciprocally increases the proximity in nuclear space among distinct downstream GATA elements. GATA-1-induced transitions in chromatin conformation are not simply the consequence of transcription inhibition and require the cofactor FOG-1. This work shows that a GATA factor exchange reconfigures higher-order chromatin organization, and suggests that de novo chromatin loop formation is employed by nuclear factors to specify repressive outcomes. [Copyright &y& Elsevier]

X-ray magnetic circular dichroism (XMCD) spectroscopy is a powerful emerging technique that measures difference in absorption of left- and right-circularly polarized X-rays by a magnetized sample, often at cryogenic temperatures. It is already well established in magnetic materials science, and it is likely to become a significant tool for the inorganic and bioinorganic communities. As with all X-ray spectroscopies, XMCD has the advantage of being element specific. Interpretation of the spectra can: provide quantitative information about the distribution of spin and orbital angular momenta from simple “sum rules”; determine spin orientations from the sign of the XMCD signal; infer spin states from magnetization curves; and separate magnetic and non-magnetic components in heterogeneous samples. With new synchrotron radiation sources and improved end stations, XMCD measurements on dilute samples such as metals in enzymes, are becoming more routine. This review first details the technology currently available for XMCD measurements and outlines the theory underlying interpretation of the spectra. It then illustrates the strengths of the XMCD technique using examples taken from bioinorganic chemistry and materials science. In this way, we aim to encourage chemists, materials scientists, and biologists to consider XMCD spectroscopy as an approach to understanding the electronic and magnetic structure of their samples. [Copyright &y& Elsevier]

Keywords: [NiFe]-hydrogenase; biocatalysis; in situ spectroscopy; metalloenzymes; vibrational spectroscopy EN [NiFe]-hydrogenase biocatalysis in situ spectroscopy metalloenzymes vibrational spectroscopy 1 1 1 07/10/21 20210712 NES 210712 B Metalloenzymes b In their Research Article on page 15854, Christian Lorent, Marius Horch, Lars Lauterbach, Ingo Zebger et al. explore redox intermediates of [NiFe]-hydrogenases by an advanced experimental approach for solvated, lyophilized, and crystallized metalloenzymes. Frontispiece: Exploring Structure and Function of Redox Intermediates in [NiFe]-Hydrogenases by an Advanced Experimental Approach for Solvated, Lyophilized and Crystallized Metalloenzymes [NiFe]-hydrogenase, biocatalysis, in situ spectroscopy, metalloenzymes, vibrational spectroscopy. [Extracted from the article]

Redox-Intermediate von [NiFe]-Hydrogenasen durch einen experimentellen Ansatz für solvatisierte, lyophilisierte und kristallisierte Metalloenzyme. Frontispiz: Ein neuer Aufbau zur Untersuchung der Struktur und Funktion von solvatisierten, lyophilisierten und kristallinen Metalloenzymen - veranschaulicht anhand von [NiFe]-Hydrogenasen Keywords: [NiFe]-Hydrogenasen; Biokatalyse; In-situ-Spektroskopie; Metalloenzyme; Schwingungsspektroskopie DE [NiFe]-Hydrogenasen Biokatalyse In-situ-Spektroskopie Metalloenzyme Schwingungsspektroskopie 1 1 1 07/10/21 20210712 NES 210712 B Metalloenzyme b Im Forschungsartikel auf S. 15988 erforschen Christian Lorent, Marius Horch, Lars Lauterbach, Ingo Zebger et al. [Extracted from the article]

Astragaloside IV (AS-IV), the major active constituent purified from Astragalus membranaceus , was previously reported to have protective effects against cardiac dysfunction. However, the underlying mechanism remains unknown. In the present study, we investigated the protective effect of AS-IV on lipopolysaccharide (LPS)-induced cardiac dysfunction and explored the potential mechanism by focusing on miRNA-1 (miR-1) at the animal and cellular levels. A series of methods were used, including echocardiography, flow cytometry, ELISA, immunofluorescence, transmission electron microscopy, RT-PCR, and western blotting. The results showed that both AS-IV and the miR-1 inhibitor improved cardiac dysfunction, reduced heart injury, inhibited apoptosis and autophagy, and regulated the expression of calcium- and mitochondrial energy metabolism-related proteins in the heart tissue of rats treated with LPS. Importantly, AS-IV downregulated the expression of miR-1 mRNA in heart tissue. All effects of AS-IV were at least partly abolished by miR-1 mimics. In the in vitro study, both AS-IV and the miR-1 inhibitor inhibited apoptosis and autophagy and regulated the expression of calcium- and mitochondrial energy metabolism-related proteins in heart cells treated with LPS. Similarly, AS-IV downregulated the expression of miR-1 mRNA in heart cells. All effects of AS-IV on cells were at least partly abolished by miR-1 mimics. Furthermore, miR-1 mimics exhibited effects similar to LPS both in animal and cellular studies. Taken together, these results suggest that AS-IV protects against LPS-induced cardiac dysfunction by inhibiting calcium-mediated apoptosis and autophagy by targeting miR-1, highlighting a new mechanism for the therapeutic effect of AS-IV on cardiac dysfunction. [ABSTRACT FROM AUTHOR]

This research evaluated the effects of enzymatic-chemical extraction (EC-SDF), subcritical water extraction (SW-SDF), and ultrasonic-chemical extraction (UC-SDF) processes on the yield, chemical composition, structural characterization, flow behavior, physicochemical, and functional properties of soluble dietary fiber (SDF) from defatted coconut flour (DCF). The optimum conditions of these three extraction methods were evaluated by response surface methodology. Compared with EC-SDF and UC-SDF, SW-SDF had the maximum yield (13.99 ± 0.12 g/100g). The structural results indicated that SW-SDF and UC-SDF possessed more complex and porous structures than EC-SDF and DCF. Moreover, they showed smaller molecular weight, stronger gelling property, higher thermal stability, and lower crystallinity. A monosaccharide composition analysis indicated that the major sugars in EC-SDF, UC-SDF and UC-SDF were mannose and galactose. Notably, the SW-SDF demonstrated the highest water and oil holding capacity, glucose adsorption, pancreatic lipase inhibition, cholesterol adsorption, and nitrite ion adsorption capacities. The above results suggest the defatted coconut flour to be a potential functional food and a possible source of cheap natural dietary fiber. • Soluble dietary fiber was recovered from the defatted coconut flour. • Three different methods were used to extract soluble dietary fiber. • The composition, structure and properties of the extracts were compared. • Subcritical water extraction method had the highest physicochemical properties. • The defatted coconut flour has great potential for the application in functional food industry. [ABSTRACT FROM AUTHOR]

Fusarium graminearum , a devastating pathogenic fungus of wheat (Triticum aestivum L.), causes fusarium head blight (FHB) and produces mycotoxins such as deoxynivalenol (DON). This study aimed to explore the potency of myriocin to control postharvest infection of F. graminearum in wheat grains. Myriocin showed excellent antifungal activity against F. graminearum , as evidenced through inhibition on spore germination and mycelial growth. The mechanism of action was investigated by analyzing changes of cell membrane permeability and serine palmitoyl transferase (SPT) activity. Results indicated that myriocin inhibited F. graminearum by disrupting permeability of membrane and result in release of cellular contents. Myriocin suppressed the SPT activity and molecular docking also proved the sC interaction of myriocin-SPT. Significant morphological alterations were observed in SEM imaging, including holes on the hyphae, contraction and disruption of mycelia. In addition, myriocin also showed inhibitory effect on toxigenic activity of F. graminearum in wheat grains by reducing more than 99.0% of deoxynivalenol (DON) and its derivative 15-acetyldeoxynivalenol (15-ADON) synthesis. Quantitative real-time PCR analysis indicated that TRI5 gene expression was downregulated by myriocin and results in the reduction of toxicity. Overall, myriocin exerted effective fungicidal activity to control F. graminearum contamination in wheat grains and provided a lead compound to develop more alternatives for pathogen control. • Myriocin inhibited spore germination and mycelial growth of F. graminearum. • Myriocin exerted a powerful fungicidal effect by disrupting plasma membrane. • Myriocin affected membrane integrity by inhibiting biological activity of SPT. • Myriocin exerted inhibitory efficacy on deoxynivalenol production in wheat grains. • Myriocin reduced toxicity of F. graminearum by downregulating TRI5 gene expression. [ABSTRACT FROM AUTHOR]

• Energy flexibility in demand response building is experimentally investigated. • Passive building thermal mass and active energy storage systems are coupled. • Pre-cooling and temperature reset are considered to assess energy flexibility. • Short-term (0.5 h) and intermediate-term (2 h) demand response are achieved. Heating, ventilation, and air conditioning (HVAC) systems, combined with the internal thermal mass of buildings, have been deemed to be promising means of providing demand response (DR) resources, particularly for buildings with active energy storage systems. DR resources, such as peak-load reduction potential, can provide grid-responsive support resulting in a high degree of grid involvement and high flexible electricity demand. In the DR field, the potential of HVAC load flexibility has been considered in buildings. In the future smart buildings, it is important to take advantage of demand-side resources to achieve real-time energy supply–demand balance sustainably. In this context, DR potential and characteristics of buildings play a pivotal role in DR programs. However, few studies have investigated the internal thermal mass's heat release and DR characteristics of buildings. Thus, a systematic experiment is conducted to study the DR potential and characteristics of internal thermal mass and active storage systems. The DR resources include the passive cooling storage from furniture, building envelope and an active water storage tank. Two DR control strategies, including pre-cooling and temperature resetting, are analyzed in this study. The experimental results show that the strategies are effective for short-term (0.5 h) and intermediate-term (2 h) DR programs. For a long-term DR program, active energy storage technology such as a water storage tank is required to satisfy the occupant's comfort requirements. Hence, we conclude that passive thermal mass and active storage systems should be simultaneously considered in practical DR programs for better DR implementation. [ABSTRACT FROM AUTHOR]

• Ablation defect on underground pipeline can be caused by lightning strike. • The ablation pit depth is proportionate to Component C of lightning current. • The ablation affected surface layer of steel has worsened grain size distribution. • The ablation affected zone has high hardness and thus poor mechanical properties. • The ablation defect should be ground off to ensure pipeline operation safety. The phenomena lightning causes failure of buried pipelines, in the form of ablation pits on pipe wall, have been reported several times in the past, and there are only few studies focusing on the formation of such failure and the impact to structural integrity in service. To study factors causing the formation of ablation pits on pipelines, lightning strike simulation experiments were conducted on pipeline steel specimens by means of an impulse current generator facility. With the obtained steel specimens from the simulation experiments, combined with the failure samples obtained in the field, metallographic examination and mechanical property tests were carried out for further fitness-for-service analysis. The results showed that the field failure samples had consistent properties with the laboratory specimens. The microstructure of the damage part transitioned in the order of, from the ablation zone inward to the matrix, a remelting zone, an HAZ surface layer, an HAZ subsurface layer, an HAZ innermost layer, and the matrix. The field and laboratory ablation failure samples showed similar changing trend of hardness, i.e., gradually decreasing from the remelting zone to the matrix. These observations demonstrate that the damage parts have distinct mechanical properties from the normal matrix. In conclusion, the ablation failure caused by lightning strike had severe impacts to the pipeline material itself, which necessitated thorough repair of the HAZ by grinding or other measures. [ABSTRACT FROM AUTHOR]

Tangeretin (TAN) is a biologically functional polymethoxylated flavonoid, extracted from the Citrus Peel (Chenpi). Although 5-demethyltangeretin (5-DT) generated through hydrolysis using a TAN precursor has superior biological function to TAN, its traditional preparation methods are difficult due to environmental hazard and low efficiency processes. In this study, the phosphoric acid (a kind of edible acids) was screened as catalysts of TAN hydrolysis conversion to 5-DT. The main conversion-influencing factors of reaction (material/liquid ratio, temperature and time) were investigated and the antioxidant activity of the modified products was determined by measuring DPPH (Diphenylpicrylbenzoquinone) free radical scavenging capacity and total reducing power. The phosphoric acid/ethanol (v/v) ratio of 7:3, material/liquid (g/L) ratio of 2:1, conversion temperature of 175 °C and conversion time of 2 h were attained as optimal conditions with a 93.71% conversion rate. Further, in vitro antioxidant and anti-lipase experiments confirmed that 5-DT was superior to TAN in total reducing power, scavenging capacity of DPPH free radicals (p < 0.01) and inhibition of lipase activities. Therefore, phosphoric acid is proposed as an alternative catalyst for the modification of TAN. Further, it provided technical support for the industrial production of 5DT and its application in functional foods. • Phosphoric acid can catalyse the conversion of TAN to 5-DT (conversion rate 93.71%). • An efficient and environmentally friendly method was proposed for 5-DT preparation. • The transformed 5-DT increased antioxidant and anti-lipase activity compared to TAN. • The proposed method shows a broad application prospects in functional foods. [ABSTRACT FROM AUTHOR]

Vascular endothelial cells act as a selective barrier between circulating blood and vessel wall and play an important role in the occurrence and development of cardiovascular diseases. Astragaloside IV (As-IV) has a protective effect on vascular endothelial cells, but its underlying mechanism remains unclear. This study is aimed at investigating the effect of As-IV on endothelial dysfunction (ED). Male Sprague-Dawley (SD) were injected intraperitoneally with 65 mg/kg streptozotocin (STZ) to induce diabetes and then administered orally with As-IV (40, 80 mg/kg) for 8 weeks. Vascular function was evaluated by vascular reactivity in vivo and in vitro. The expression of calpain-1 and eNOS in the aorta of diabetic rats was examined by western blot. NO production was measured using nitrate reductase method. Oxidative stress was determined by measuring SOD, GSH-px and ROS. Our results showed that As-IV administration significantly improved diabetes associated ED in vivo , and both NAC (an antioxidant) and MDL-28170 (calpain-1 inhibitor) significantly attenuated hyperglycemia-induced ED in vitro. Meanwhile, pretreatment with the inhibitor l-NAME nearly abolished vasodilation to ACh in all groups of rats. Furthermore, As-IV increased NO production and the expression of eNOS in the thoracic aorta of diabetic rats. In addition, the levels of ROS were significantly increased, and the activity of SOD and GSH-px were decreased in diabetic rats, while As-IV administration reversed this change in a concentration-dependent manner. These results suggest that As-IV improves endothelial dysfunction in thoracic aortas from diabetic rats by reducing oxidative stress and calpain-1. [ABSTRACT FROM AUTHOR]

Structure/material requires simultaneous consideration of both its design and manufacturing processes to dramatically enhance its manufacturability, assembly and maintainability. In this work, a novel design framework for structural/material with a desired mechanical performance and compelling topological design properties achieved using origami techniques is presented. The framework comprises four procedures, including topological design, unfold, reduction manufacturing, and fold. The topological design method, i.e., the solid isotropic material penalization (SIMP) method, serves to optimize the structure in order to achieve the preferred mechanical characteristics, and the origami technique is exploited to allow the structure to be rapidly and easily fabricated. Topological design and unfold procedures can be conveniently completed in a computer; then, reduction manufacturing, i.e., cutting, is performed to remove materials from the unfolded flat plate; the final structure is obtained by folding out the plate from the previous procedure. A series of cantilevers, consisting of origami parallel creases and Miura-ori (usually regarded as a metamaterial) and made of paperboard, are designed with the least weight and the required stiffness by using the proposed framework. The findings here furnish an alternative design framework for engineering structures that could be better than the 3D-printing technique, especially for large structures made of thin metal materials. [ABSTRACT FROM AUTHOR]

Fullerene nanostructures are well known for their unique morphology, physical and mechanical properties. The thermal stability of fullerene nanostructures, such as their sublimation at high temperature is also very important for studying their structures and applications. In this work, We observed fullerene nanowhiskers (FNWs) in situ with scanning helium ion microscopy (HIM) at elevated temperatures. The FNWs exhibited different stabilities with different thermal histories during the observation. The pristine FNWs were decomposed at the temperatures higher than 300 °C in a vacuum environment. Other FNWs were protected from decomposition with an amorphous carbon (aC) film deposited on the surface. Based on high spacial resolution, aC film with periodic structure was deposited by helium ion beam induced deposition (IBID) on the surface of FNWs. Annealed at the high temperature, the fullerene molecules were selectively sublimated from the FNWs. The periodic structure was formed on the surface of FNWs and observed by HIM. Monte Carlo simulation and Raman characterization proved that the morphology of the FNWs was changed by helium IBID at high temperature. This work provides a new method of fabricating artificial structure on the surface of FNWs with periodic aC film as a mask. [ABSTRACT FROM AUTHOR]

The article discusses the association of Bromodomain protein Brd3 with the acetylated GATA1 to promote its chromatin occupancy at erythroid target genes. Study shows that both Brd3 and GATA1 interact physically in a manner that is dependent on acetylation. It points out that this interaction is necessary for the occupancy of proteins on chromatin and the normal red cell-specific gene expression.