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Protein-surfactant interactions have a significant influence on food functionality, which has attracted increasing attention. Herein, the effect of glycolipid mannosylerythritol lipid-A (MEL-A) on the heat-induced soy glycinin (11S) aggregates was investigated by measuring the structure, binding properties, interfacial behaviors, and emulsification characteristics of the aggregates. The results showed that MEL-A led to a decrease in the surface tension, viscoelasticity, and foaming ability of the 11S aggregates. In addition, MEL-A with a concentration above critical micelle concentration (CMC) reduced the random aggregation of 11S protein after heat treatment, thus facilitating the formation of self-assembling core-shell particles composed of a core of 11S aggregates covered by MEL-A shells. Infrared spectroscopy, circular dichroism spectroscopy, fluorescence spectroscopy, and isothermal titration calorimetry also confirmed that the interaction forces between MEL-A and 11S were driven by hydrophobic interactions between the exposed hydrophobic groups of the protein and the fatty acid chains or acetyl groups of MEL-A, as well as the hydrogen bonding between mannosyl-D-erythritol groups of MEL-A and amino acids of 11S. The findings of this study indicated that such molecular interactions are responsible for the change in surface behavior and the enhancement of foaming stability and emulsifying property of 11S aggregates upon heat treatment. [ABSTRACT FROM AUTHOR]

The joint participation of multiple subjects is crucial for environmental governance. Using panel data for 273 Chinese cities during 2013–2019, this study investigates the impact and mechanism of public demands on environmental pollution. The results demonstrate that public demands measured by the number of environmental complaints placed on government leaders significantly reduce environmental pollution. Furthermore, increases in the rate and speed of government responses improve the effect of public demands on environmental governance. Public demands placed on provincial leaders reduce local environmental pollution to a greater extent than public demands placed on prefectural and county leaders. Province-level governments are more willing to consider public opinions and attach more importance to environmental governance; Prefecture-level governments prioritize province-level governments' attention to the environment when implementing environmental governance. Moreover, strong political ties between provincial and prefectural leaders and long tenures among prefectural leaders strengthen the pollution reduction effect of public demands placed on provincial leaders. The reduction effect of environmental complaints on pollution emission is more significant in cities with high level of Internet construction and environmental disclosure. Our results illustrate the role of public demands in environmental governance, offering a reference for developing effective environmental policies. • Public demands placed on government leaders reduce environmental pollution. • Effects are strengthened under effective government response. • Demands to provincial leaders are more effective than those to prefectural leaders. • Strong political ties and long tenures of prefectural leaders enhance the effects. [ABSTRACT FROM AUTHOR]

Currently, most scene classification algorithms are trained and evaluated based on a single dataset. However, practical applications are not usually restricted to specific satellite platforms or datasets. Researchers generally train a model on one dataset and require the model to perform tasks with another dataset, leading to a data shift problem and performance decrease in practical applications. To address this problem, this study presents a metric-based few-shot classification method with L 2 -norm prototypical networks. Specifically, a carefully designed L 2 -norm layer was introduced into prototypical networks. The proposed L 2 -norm layer applies L 2 -norm operations to prototypes and query features to mitigate the length fluctuations caused by the data shift problem. With this layer, the L 2 -norm prototypical networks maintain the ability to identify novel classes and limit the effects of data discrepancies. The proposed L 2 -norm layer improves the classification accuracy by 0.42% to 2.41% on various public datasets. Moreover, L 2 -norm prototypical networks outperform other methods by 0.02% to 34.38%. Comprehensive experiments consistently demonstrate the advantages of the proposed method in tackling the data shift problem. [ABSTRACT FROM AUTHOR]

Mannosylerythritol lipids (MELs) are novel biosurfactants performing excellent physical-chemical properties as well as bioactivities. This study is aimed to explore the antibacterial and antibiofilm activity of mannosylerythritol lipids against foodborne gram-positive Staphylococcus aureus. The results of growth curve and survival rate revealed the significant inhibitory effect of MELs against S. aureus. The visualized pictures by scanning electron microscope and transmission electron microscope exposed apparent morphological and ultrastructure changes of MEL-treated cells. Furthermore, flow cytometry confirmed that MELs have promoted cell apoptosis and damaged the cell membrane. Notably, MEL-A also exhibited outstanding antibiofilm activity against S. aureus biofilm on different material surfaces including polystyrene, glass, and stainless steel, verified by confocal laser scanning microscope. These findings suggest that the antimicrobial activity of MELs is related to inhibit planktonic cells and biofilm of S. aureus, indicating that it has potential to be an alternative to antibacterial agents and preservatives applied into food processing. Key Points • MELs have strong antibacterial activity against Staphylococcus aureus. • MELs mainly damage the cell membrane of Staphylococcus aureus. • Mannosylerythritol lipids inhibit the bacterial adhesion to remove biofilm. [ABSTRACT FROM AUTHOR]

Compacted bentonite is usually used as the backfill material in underground storage of radioactive waste due to its swelling properties and low permeability. To understand the effects of the degree of saturation and stress cycle on the barrier properties of compacted bentonite, gas permeability tests were performed on highly compacted bentonite with different dry densities, water contents and stress cycles. The testing results show that the degree of saturation and stress cycle both have significant influences on the gas permeability of unsaturated compacted bentonite samples. As the saturation or confining stress increases, gas permeability of the samples is decreased by no more than 3 orders of magnitude. Moreover, under the condition of the same dry density, the greater the degree of saturation, the faster the decline of gas permeability of samples during loading; under the condition of the same degree of saturation, it shows that larger initial dry density can cause gentler decrease of the gas permeability of samples. A slight recovery in gas permeability was observed during unloading process of confining stress, and the decline of gas permeability caused by increasing confinements is mainly irreversible. Different from saturated/nearly-saturated samples, gas migration in the low/medially saturated compacted bentonite sample is considered to be dominated by single-phase advection in the connected pores of the unsaturated zone. The present work implicates that the effect of the degree of saturation and the stress path on the gas permeability of the backfill material should be taken into account during the construction period and early stage of operation of the radioactive waste. • A double-end pressing method was adopted to produce compacted Gaomiaozi bentonite samples. • Gas permeability of the unsaturated compacted Gaomiaozi bentonite with different properties under stress cycle was tested. • It shows that the material properties and stress cycle have significant influences on the gas permeability of samples. • Loading of confining pressure causes huge decrease in gas permeability, while unloading generates slight recovery. [ABSTRACT FROM AUTHOR]

• KMnO 4 was used to treat Li-rich layered oxides for the first time. • Reconstruct the surface lattice structure. • The electrochemical performance was enormous enhanced after treatment. • Improve the conductivity of Li+ and reduce the impedance. • Simple operation and high efficiency. Li-rich layered materials are facing the problems of low initial coulomb efficiency and poor rate performance, which seriously restrict its commercial development. Herein, we modified Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 by KMnO 4 to reconstruct the surface lattice and improve the Li+ conduction efficiency. The material acquired higher initial coulomb efficiency after treatment. Moreover, the initial specific capacity of the treated material was increased from 214.4 mAh g−1 to 262.7 mAh g−1 at 0.2 C with the voltage range from 2.0 V to 4.8 V, and 88% remained after 100 cycles. Even at 10 C, the specific capacity of 91.6 mAh g−1 can still be obtained, which is three times more than the pristine. The method of surface treatment with KMnO 4 provides a new idea for the commercial development of Li-rich layered materials in the future. [ABSTRACT FROM AUTHOR]

• Mannosylerythritol lipid-A improved the rheological property and water distribution of frozen dough. • Mannosylerythritol lipid-A strengthened the gluten network of frozen dough. • Mannosylerythritol lipid-A enhanced the textural property of bread. • Mannosylerythritol lipid-A effectively sterilized Bacillus cereus in frozen dough. Biosurfactants have been put into applications in breadmaking industry, while the effects of mannosylerythritol lipid-A (MEL-A) on gluten network of frozen dough, bread quality and microbial spoilage were firstly investigated in this study. Rheology and differential scanning calorimetry (DSC) analysis showed that MEL-A significantly improved the rheological properties of frozen dough and reduced the content of frozen water. Further experiments showed that MEL-A promoted the formation of aggregates by interacting with gluten protein, and strengthened the gluten network through molecular weight distribution measurement and microstructure observation, effectively avoiding the destruction of ice crystals. A series of bread assessments illustrated MEL-A improved the loaf volume, gas retention ability and textural property. In addition, MEL-A (1.5%) killed 99.97% of the vegetative cells of Bacillus cereus and 75.54% of the spores, and at the same time had a slight inactivation effect on yeast. These results indicate that MEL-A has broad application prospects in the baking industry and the storage stage of flour products. [ABSTRACT FROM AUTHOR]

Highlights: [•] Zn30Cr4.5/γ-Al2O3 showed good performance on the amination of allyl alcohol to propionitrile. [•] The hydrogen derived from dehydrogenation in situ acted as a source for hydrogenation. [•] Chromium could diminish the size of ZnAl2O4 crystallites. [•] The performance of the catalyst can be recovered on line by combustion. [ABSTRACT FROM AUTHOR]

Ethyl carbamate (EC) is a potential carcinogen that forms spontaneously during Chinese rice wine fermentation. The primary precursor for EC formation is urea, which originates from both external sources and arginine degradation. Urea degradation is suppressed by nitrogen catabolite repression (NCR) in Saccharomyces cerevisiae. The regulation of NCR is mediated by two positive regulators (Gln3p, Gat1p/Nil1p) and two negative regulators (Dal80p/Uga43p, Deh1p/Nil2p/GZF3p). DAL80 revealed higher transcriptional level when yeast cells were cultivated under nitrogen-limited conditions. In this study, when DAL80-deleted yeast cells were compared to wild-type BY4741 cells, less urea was accumulated, and genes involved in urea utilization were up-regulated. Furthermore, Chinese rice wine fermentation was conducted using dal80Δ cells; the concentrations of urea and EC were both reduced when compared to the BY4741 and traditional fermentation starter. The findings of this work indicated Dal80p is involved in EC formation possibly through regulating urea metabolism and may be used as the potential target for EC reduction. [ABSTRACT FROM AUTHOR]

Supercapacitors, are commonly connected to the sediment microbial fuel cell (SMFC) and then serves as the input source for the power management system (PMS). To compare and analyze functions of supercapacitors in SMFC energy harvesting, PMSs (PMS I and PMS II) are powered by SMFC stack or charged supercapacitors as the input source. Tests indicate that the charged supercapacitor results in a higher input power and a larger output power. In addition, the overall efficiency of PMSs is rarely affected by the capacitance, but the initial voltage of the supercapacitor. By charging supercapacitors connected in parallel and then discharging them in series, the overall power efficiency of PMS II is increased from 44.33% to 69.52%. In conclusion, supercapacitors firstly storing SMFC energy is beneficial to provide sufficient energy, resulting in an improved PMS performance. Further, these results can be useful and informative to PMS design for efficiently harvesting and utilize MFC energy. • Two common power management systems (PMSs) are comparative studied. • The MPPT-based PMS extracts higher power from the SMFC stack and supercapacitor. • Charged supercapacitors provide higher input power for the PMSs. • PMS performance is affected by the initial voltage of supercapacitor. • Different arrangements of supercapacitors are studied. [ABSTRACT FROM AUTHOR]

[Display omitted] Methicillin-resistant Staphylococcus aureus (MRSA) is drug-resistant and biofilm-forming pathogenic bacteria with severe morbidity and mortality, and has been continuously detected in food products in recent years. Mannosylerythritol lipids (MELs) are novel biosurfactants and perform antibacterial property against gram-positive bacteria. Ultrasound has been applied into food sterilization as non-thermal techniques and has advantage of maintaining food nutrition and flavor over heat pasteurization. In this work, the synergistic treatment of ultrasound and MEL-A was used to combat planktonic cells and biofilm of MRSA. As a result, the combined treatment has exhibited remarkable antibacterial effect proved by enumeration of viable microbes. Furthermore, flow cytometry, scanning electron microscopy and transmission electron microscopy revealed ultrasound has enhanced the inhibitory effect of MEL-A through exacerbating cell membrane damage. On the other hand, the collaborating working modes to eradicate MRSA biofilm were disturbing cell adhesion to surface by MEL-A and destructing mature biofilm mechanically by ultrasound, reaching to over 90% of clearance rate. The findings of this study illustrated the synergistic antimicrobial mechanism of ultrasound and MEL-A treatments, and offered theoretical basis for their potential applications in food preservation. [ABSTRACT FROM AUTHOR]

Glycolipid biosurfactants are natural amphiphiles and have gained particular interest recently in their biodegradability, diversity, and bioactivity. Microbial infection has caused severe morbidity and mortality and threatened public health security worldwide. Glycolipids have played an important role in combating many diseases as therapeutic agents depending on the self-assembly property, the anticancer and anti-inflammatory properties, and the antimicrobial properties, including antibacterial, antifungal, and antiviral effects. Besides, their role has been highlighted as scavengers in impeding the biofilm formation and rupturing mature biofilm, indicating their utility as suitable anti-adhesive coating agents for medical insertional materials leading to a reduction in vast hospital infections. Notably, glycolipids have been widely applied to the synthesis of novel antimicrobial materials due to their excellent amphipathicity, such as nanoparticles and liposomes. Accordingly, this review will provide various antimicrobial applications of glycolipids as functional ingredients in medical therapy. [ABSTRACT FROM AUTHOR]

Ten previously undescribed meroterpenoids, cyclohexenoneterpenes A−J (1 − 7 , 18 − 20), together with 10 known analogues (8 − 17) were isolated from the mangrove-associated fungus Penicillium sp. N-5. Their structures were elucidated on the basis of extensive spectroscopic and mass spectrometric data. The absolute configurations of the undescribed compounds were assigned by electronic circular dichroism calculations, the modified Mosher's method, NMR calculations and DP4+ analysis. In the bioassay, compounds 10 , 11 , 15 , and 20 exhibited cytotoxicities against SNB-19, MDA-MB-231, MDA-MB-435 and HCT-116 cell lines with IC 50 values ranging from 1.4 to 19.1 μM. [Display omitted] • Ten undescribed meroterpenoids were isolated from the mangrove-associated fungus. • The modified Mosher's method was used to determine the absolute configurations. • Isoprenoid epoxycyclohexenone type of meroterpenoids have cytotoxic activities. [ABSTRACT FROM AUTHOR]

• The optimized ultrasound treatment significantly promoted the growth and yield of EPS. • The fermentation kinetics of ABSC was significantly affected by ultrasound. • Ultrasonic stimulation can improve the permeability of ABCS mycelium cells. • Ultrasound changed mycelium morphology and reduce mycelium diameter. Agaricus bitorquis (Quél.) Sacc. Chaidam (ABSC), is a kind of rare edible macrofungi with a variety of biological ingredients, especially its polysaccharides. However, the low yield limits the popularity and promotion of rare edible macrofungi as well as its macrofungi polysaccharides. Hence, developing a positive and effective cultivation method is of great importance. Herein, an efficient ultrasonic (US) stimulation strategy was developed to improve mycelial growth and exopolysaccharides (EPS) biosynthesis from ABSC in submerged cultivation without light. A time design was employed to illustrate the effect of various process parameters including duration, starting point and times of US irradiation on ABSC productivity. 5 min US treatment for once upon ABSC after fermentation for 48 h could significantly improve EPS production and mycelia growth by above 26% and 15.03%, respectively. Furthermore, six times of 5 min US treatment could make the amount of EPS reach 218.78 ± 17.09 mg/g, which was 2.52-fold higher than that of the control. Moreover, the enhanced effect induced by US was further expounded by fermentation kinetics. Besides, the US treatment could increase mycelia permeability, change structure and reduce mycelial diameter to promote mass transfer, resulting in the improvement of EPS production and mycelia accumulation. The results demonstrated that the present proposed US intensification approach could be useful to boost up the fermentation of ABSC, which possibly applied to yield increase and fermentation product acquisition of macrofungi. [ABSTRACT FROM AUTHOR]

As power semiconductor devices are the key components of hybrid DC circuit breakers (HCBs), how to select suitable devices is critical for the whole HCB design. First, this paper compared the general characteristics of press pack insulated gate bipolar transistor (IGBT), injection-enhanced gate transistor (IEGT), and integrated gate commutated thyristor (IGCT). Then working conditions of devices were analyzed from the perspective of HCBs. According to these, vital features of devices including maximum turn-off current, on-state voltage, conduction ability, and robustness of power semiconductor devices were carefully analyzed and compared. Related experiments were implemented to compare maximum turn-off capability, and the 4.5 kV/3 kA IGBT/IEGT was able to turn off 19 and 22 kA respectively after 5-ms current conduction. Analysis and experiments indicated that IGCT was suitable for natural commutation low-voltage and low-current hybrid circuit breakers, due to its low on-state voltage and huge surge current conduction ability. Comparatively, IGBT and IEGT were more suitable for very high current interruption, and IEGT was the superior selection among available commercial devices. However, the interference should be considered in applications. [ABSTRACT FROM AUTHOR]

Silicon is one of the most promising candidates for anode materials of lithium-ion batteries, due to its high theoretical capacity and low working voltage, etc. Nonetheless, silicon has huge volume change during the lithiation/delithiation, resulting in poor cycle performance. Herein, novel double-shell-structured Si@Al 2 O 3 @C nanoparticles are prepared to obtain stable electrochemical performance. The improved performance can be attributed to novel double-shell structure, which greatly improves the conductivity of material, stabilizes solid-electrolyte interface (SEI) film, and releases the expansion stress of silicon. Si@Al 2 O 3 @C nanoparticles deliver a specific capacity of 1316.1 mAh g−1 at 1 A g−1 after 100 cycles, and the average discharge capacity of Si@Al 2 O 3 @C nanoparticles at 4 A g−1 still remains 781.6 mAh g−1. Additionally, the initial Coulombic efficiency (ICE) of material is as high as 82.9%. This work offers a significant method to further enhance the performance of lithium-ion batteries. [Display omitted] • For lithium-ion batteries, double-shell-structured Si@Al 2 O 3 @C anode is reported for the first time. • The double-shell structure can improve conductivity, stabilize SEI film, and release the expansion pressure of silicon. • Si@Al 2 O 3 @C nanoparticles show a high ICE of 82.9% and a reversible capacity of 1316.1 mAh g−1 at 1 A g−1 after 100 cycles. • Simple two-step synthesis. [ABSTRACT FROM AUTHOR]

[Display omitted] • LiTi 2 (PO 4) 3 as a precursor is synthesized by the solvothermal method and calcinated in N 2. • LiTi 2 (PO 4) 3 –7h exhibits excellent electrochemical performance. • LiTi 2 (PO 4) 3 –7h exhibits the initial discharge capacity of 123.3 mAh·g−1 at 10C. Nanoparticle LiTi 2 (PO 4) 3 was prepared by solvothermal and calcination methods. LiTi 2 (PO 4) 3 -xh(x = 5, 7, 9, 13) was successfully synthesized under different calcination times in nitrogen atmosphere, and LiTi 2 (PO 4) 3 –7h showed excellent rate and electrochemical performance. It delivered discharge capacities of 141.2, 119.9, 109.8, 98.2, 87.3, and 76.7 mAh·g−1 at rates of 0.5, 1, 2, 5, 10, and 20C, respectively. In particular, its initial discharge capacity can reach 123.3 mAh·g−1 at the high rate of 10C. Hence, these superior properties demonstrate that LiTi 2 (PO 4) 3 –7h has great application advantages as a cathode for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

• For lithium-ion batteries, phosphorus-doped phenol formaldehyde resin is used as carbon source for the first time. • The doping of phosphorus increases the active sites of the material, and improves the Li+ diffusion coefficient. • The Si@C/P anode possesses an excellent discharge capacity of 1873 mAh g−1 at 1 A g−1 after 100 cycles. • Simple and convenient synthesis method. [Display omitted] As one of the most promising electrode materials for lithium-ion batteries, silicon offers a high theoretical capacity, but it has been greatly limited by a volume expansion effect and the formation of unstable solid–electrolyte interface (SEI) film. Herein, Si@C/P nanoparticles with excellent electrochemical properties were prepared simply by sol-gel method and carbonization process. For lithium-ion batteries, phosphorus-doped phenol formaldehyde resin was used as carbon source for the first time, and phosphorus was successfully doped into carbon skeleton. The synergistic effect of carbon layer and phosphorus doping limits the volume expansion of silicon, and improves the diffusion rate of Li+. The Si@C/P anode exhibits a high initial Coulombic efficiency (ICE) of 84.4% and a specific capacity of 1873 mAh g−1 at 1 A g−1 after 100 cycles. The material shows a good rate performance, the average specific capacity reaches 1422.3 mAh g−1 even at a high current density of 4 A g−1, demonstrating a bright perspective. [ABSTRACT FROM AUTHOR]

Abstract: Pentanitromonoformylhexaazaisowurtzitane (PNMFIW) was synthesized by the nitrolysis of tetraacetyldiformylhexaazaisowurtzitane (TADFIW) in mixed nitric and sulfuric acids and structurally characterized by element analysis, FT-IR, MS and 1H NMR. Single crystals of PNMFIW were grown from aqueous solution employing the technique of controlled evaporation. PNMFIW belongs to the orthorhombic system having four molecules in the unit cell, with space group P2(1)2(1)2(1) and the lattice parameters a =8.8000(18)Å, b =12.534(2)Å, and c =12.829(3)Å. The calculated density reaches 1.977g/cm3 at 93K, while the experimental density is 1.946g/cm3 at 20°C. The calculated detonation velocity and pressure of PNMFIW according to the experimental density are 9195.76m/s and 39.68GPa, respectively. PNMFIW is insensitive compared with ɛ-HNIW through drop hammer impact sensitivity test. [Copyright &y& Elsevier]

Silicon has demonstrated inordinate potential as anode material for next-generation lithium-ion batteries due to its high theoretical specific capacity. Nevertheless, the structural dilapidation during the lithiation/delithiation process has restricted its large-scope application. To conquer these challenges, we design a novel reduced graphene oxide (rGO)-coated Si@SiO x @β-Bi 2 O 3 /Bi composite by a facile one-pot method. The Bi 2 O 3 shell chiefly guarantees the structural integrity of Si-core during cyclings and synergizes with Bi nanodots to expediting Li+/e− transport kinetics. rGO mainly acts as the carrier to attaining the twofold goals of ameliorating the electronic conductivity and cushioning the stress from volume expansion. Therefore, the novel rGO-coated Si@SiO x @β-Bi 2 O 3 /Bi composite exhibits a high specific capacity of 1784 mAh g−1 at 1 A g−1 after 200 cycles and a good cycling stability of 1007 mAh g−1 at a high rate of 4 A g−1. [Display omitted] [ABSTRACT FROM AUTHOR]

Flavonoids belong to a class of plant secondary metabolites that have a polyphenol structure. Flavonoids show extensive biological activity, such as antioxidative, anti-inflammatory, anti-mutagenic, anti-cancer, and antibacterial properties, so they are widely used in the food, pharmaceutical, and nutraceutical industries. However, traditional sources of flavonoids are no longer sufficient to meet current demands. In recent years, with the clarification of the biosynthetic pathway of flavonoids and the development of synthetic biology, it has become possible to use synthetic metabolic engineering methods with microorganisms as hosts to produce flavonoids. This article mainly reviews the biosynthetic pathways of flavonoids and the development of microbial expression systems for the production of flavonoids in order to provide a useful reference for further research on synthetic metabolic engineering of flavonoids. Meanwhile, the application of co-culture systems in the biosynthesis of flavonoids is emphasized in this review. [ABSTRACT FROM AUTHOR]

• The hollow spherical LiNi 0.5 Mn 1.5 O 4 (HS-LNMO) was synthesized by a simple hydrothermal method. • HS-LNMO exhibits excellent electrochemical performances. • Capacity retention of 95.1% could be obtained at 1C after 100 cycles. Hollow spherical LiNi 0.5 Mn 1.5 O 4 (LNMO) material was synthesized by a glucose-assisted hydrothermal method. The glucose was mainly used to control the morphology of LNMO. The initial discharge capacity at 1C was 124.6 mAhg−1. And even at 10C, 91.8 mAhg−1 could still be obtained. Moreover, its excellent structural stability ensures the integrity of the electrode and capacity retention of 95.1% could be obtained at 1C after 100 cycles. The results show that this unique hollow sphere-like structure can promote the transport of Li+ and improve lithium storage capacity. Therefore, we conclude that the addition of glucose has a great improvement in cycle stability and rate capability. [ABSTRACT FROM AUTHOR]