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The secondary metabolites isolated from soil fungi have received more and more attention, especially new compounds that exhibited good biological activities. In this review, a total of 546 new compounds are included in the relevant literature since 2011. The new compounds are isolated from soil fungi, We divided these compounds into seven categories, including alkaloids, terpenoids, steroids, ketones, phenylpropanoids, quinones, esters, lactones, etc. In addition, the biological activities and structure-activity relationships of these compounds have also been fully discussed. The activities of these compounds are roughly divided into eight categories, including anticancer activity, antimicrobial activity, anti-inflammatory activity, antioxidant activity, antiviral activity, antimalarial activity, immunosuppressive activity and other activities. Since natural products are an important source of new drugs, this review may have a positive guiding effect on drug screening.

Methanobactins (Mbns) are a family of copper-binding peptides involved in copper uptake by methanotrophs, and are potential therapeutic agents for treating diseases characterized by disordered copper accumulation. Mbns are produced via modification of MbnA precursor peptides at cysteine residues catalyzed by the core biosynthetic machinery containing MbnB, an iron-dependent enzyme, and MbnC. However, mechanistic details underlying the catalysis of the MbnBC holoenzyme remain unclear. Here, we present crystal structures of MbnABC complexes from two distinct species, revealing that the leader peptide of the substrate MbnA binds MbnC for recruitment of the MbnBC holoenzyme, while the core peptide of MbnA resides in the catalytic cavity created by the MbnB–MbnC interaction which harbors a unique tri-iron cluster. Ligation of the substrate sulfhydryl group to the tri-iron center achieves a dioxygen-dependent reaction for oxazolone-thioamide installation. Structural analysis of the MbnABC complexes together with functional investigation of MbnB variants identified a conserved catalytic aspartate residue as a general base required for MbnBC-mediated MbnA modification. Together, our study reveals the similar architecture and function of MbnBC complexes from different species, demonstrating an evolutionarily conserved catalytic mechanism of the MbnBC holoenzymes.

A hierarchical micro/nanostructured Cu(100)-rich copper hollow fiber as a gas penetration electrode (GPE) efficiently reduces CO2 to C2+ products.

Electrochemical conversion of CO

Laser-induced breakdown spectroscopy (LIBS) is a capable technique for elementary analysis, while LIBS quantitation is still under development. In quantitation, precise laser focusing plays an important role because it ensures the distance between the laser and samples. In the present work, we employed spectral intensity as a direct way to assist laser focusing in LIBS quantitation for copper alloys. It is found that both the air emission and the copper line could be used to determine the position of the sample surface by referencing the intensity maximum. Nevertheless, the fine quantitation was only realized at the position where the air emission (e.g. O (I) 777.4 nm) reached intensity maximum, and also in this way, a repeatable quantitation was successfully achieved even after 120 days. The results suggested that the LIBS quantitation was highly dependent on the focusing position of the laser, and spectra-assisted focusing could be a simple way to find the identical condition for different samples’ detection. In the future, this method might be applicable in field measurements for LIBS analysis of solids.

According to the comprehensive test requirements of commercial and self-developed marine sensors carried on the Smart Float, an ocean sensor integrated interface platform is developed, which is composed of underwater connection unit and shore-based control center. The underwater connection unit contains the main controller, serial port server, Ethernet switch, and remote transmission equipment, etc. and it communicates with the shore-based control center through a twisted-pair or armored cable. The underwater connection unit is designed to implement the functions of power management, sensor electric current monitoring, environment temperature monitoring, and data self-storage, while the shore-based control center is designed for remote control, curve drawing, and data storage. The offshore test results indicate that our design provides an efficient and stable platform to simulate the Smart Float, ROV and HOV interfaces, and carry out the integrated connection test for the marine sensors. It demonstrates the outstanding ability for the comparison of self-developed sensors and commercial sensors, as well as the scientific application of carbon storage and oxygen capacity

Electrocatalytic reduction of CO2 to fuels and chemicals is one of the most attractive routes for CO2 utilization. However, low efficiency and poor stability restrict the practical application of most conventional electrocatalysts. Here, a silver hollow fiber electrode is presented as a novel self-supported gas diffusion electrode for efficient and stable CO2 electroreduction to CO. A CO faradaic efficiency of over 92% at current densities of above 150 mA∙cm−2 is achieved in 0.5 M KHCO3 for over 100 h, which is comparable to the most outstanding Ag-based electrocatalysts. The electrochemical results suggest the excellent electrocatalytic performance of silver hollow fiber electrode is attributed to the unique pore structures providing abundant active sites and favorable mass transport, which not only suppresses the competitive hydrogen evolution reaction (HER) but also facilitates the CO2 reduction kinetics.

Conversion of CO2 to valuable chemicals driven by renewable electricity via electrocatalytic reduction processes is of great significance for achieving carbon neutrality. Copper-based materials distinguish themselves from other electrocatalysts for their unique capability to produce multicarbon compounds in CO2 electroreduction. However, the intrinsic active composition and C–C coupling mechanism of copper-based catalysts are still ambiguous. This is largely due to the absence of appropriate in situ approaches to monitor the complicated processes of CO2 electroreduction. Here, we adopted operando spectroscopy techniques, including Raman and infrared, to investigate the evolution of compositions and intermediates during gas-phase CO2 electroreduction on Cu foam, Cu2O nanowire and CuO nanowire catalysts. Although all the three copper-based catalysts possessed the activity of electroreducing gas-phase CO2 to multicarbon oxygenates, Cu2O nanowires showed the much superior performance with a 71.9% Faradaic efficiency of acetaldehyde. Operando Raman spectra manifested that the cuprous oxide remained stable during the whole gas-phase CO2 electroreduction, and operando diffuse reflectance infrared Fourier transform spectroscopy (DRFITS) results provide direct evidences of key intermediates and their evolutions for producing multicarbon oxygenates, in consistence with the density functional theory calculations.

With the rapid urbanisation in most parts of the world, modern transit systems have been made more and more convenient, reliable and integrated. What the situation will be like when multiple operators overlap the service areas partially or fully originates this research topic. In this optimisation research study, the objective function is formulated as the sum of operator cost and user cost. The formulation of total cost in different coordination scenarios are analyzed under three operator policies, i.e. cooperation, competition and independence respectively. By categorizing different groups of passengers in detail, the passenger flows are estimated by transit path choice model. The optimal results in Stackelberg equilibrium can be obtained by the optimisation procedure. The objective functions in scenarios of no coordination and common headway coordination, which are identified as nonlinear programming problem can be solved by considering the first order and second order conditions; whereas objective function in integer-ratio headway coordination is identified as mixed integer nonlinear programming problem. Evaluation of this model is conducted first, and then extensive sensitivity analysis is carried out to verify the evaluation results. Finally the conclusion can be drawn that integer-ratio headway coordination is an efficient and feasible method when operators adopted cooperation policy, whereas it is not recommended for them to adopt a competition policy, because the coordination benefits are not significant and sometimes they may even get worse. This research focuses on optimal coordination of public transit operated by multiple operators during off-peak hours. The results would be beneficial to making regulatory policies as references. Doctor of Philosophy (CEE)

Photocatalytic conversion of CO2 into chemicals has been recognized as a promising strategy for combining virtuous carbon cycle and solar energy storage. The realization of this process depends on an efficient catalyst to activate CO2 molecule utilizing solar light. Rational design of hybrid structural photocatalyst comprising multiple components with distinctive functionalities is highly desirable for gas-phase CO2 photocatalytic conversion. Here we report iron oxide species modified zeolite ZSM-5 by function ion preadsorption assistance for the efficient photocatalytic reduction of CO2 to CO and aldehyde. Derived from the synergistic FeII and FeIII functions on ZSM-5, the FeOX/ZSM-5 composite catalysts furnished favorable band gaps and active sites for CO2 adsorption/activation as well as C C coupling. Significantly, the 3 wt% FeOX/ZSM-5 catalyst exhibits a high CO2 conversion rate of 17.6 μmol gcat−1 h−1, with a high selectivity (43.1 %) for aldehyde generation (7.6 μmol gcat−1 h−1).

The classical swine fever virus C-strain vaccine (C-strain vaccine) plays a vital role in preventing and controlling the spread of classical swine fever (CSF). However, the protective mechanisms of C-strain vaccine and cellular immunity conferred by T cell receptors (TCRs) are less well defined. We aimed to analyse the association between the complementarity determining region 3 (CDR3) spectratype of αβTCR in CD4+ T cells and C-strain vaccine; and to find conserved CDR3 amino acid motifs in specific TCR α- and β-chains. We found that the CDR3 spectratype showed dynamic changes correlating with C-strain vaccine immunisation and that TCR AV5S/8–3S/8–4S/14/38 and BV4S/6S/7S/15S/30 gene families showed clonal expansion in immunised pigs. The sequences of CDR3 from these clonally expanded T cells indicated a high frequency of the ‘KLX’ motif in the TCR α chain and the ‘GGX’ motif in β chain, and Jα39, Jα43, Jβ2.5 and Jβ2.3 genes were also found in high frequency. To the best of our knowledge, this is the first report describing the dynamic changes of αβTCRs and conserved CDR3 amino acid motifs in CD4+ T cells from C-strain vaccine-immunised pigs, which will provide a basis for the development of high-efficiency epitope vaccines.

The classical swine fever virus C-strain vaccine (C-strain vaccine) plays a vital role in preventing and controlling the spread of classical swine fever (CSF). However, the protective mechanisms of C-strain vaccine and cellular immunity conferred by T cell receptors (TCRs) are less well defined. We aimed to analyse the association between the complementarity determining region 3 (CDR3) spectratype of αβTCR in CD4+ T cells and C-strain vaccine; and to find conserved CDR3 amino acid motifs in specific TCR α- and β-chains. We found that the CDR3 spectratype showed dynamic changes correlating with C-strain vaccine immunisation and that TCR AV5S/8–3S/8–4S/14/38 and BV4S/6S/7S/15S/30 gene families showed clonal expansion in immunised pigs. The sequences of CDR3 from these clonally expanded T cells indicated a high frequency of the ‘KLX’ motif in the TCR α chain and the ‘GGX’ motif in β chain, and Jα39, Jα43, Jβ2.5 and Jβ2.3 genes were also found in high frequency. To the best of our knowledge, this is the first report describing the dynamic changes of αβTCRs and conserved CDR3 amino acid motifs in CD4+ T cells from C-strain vaccine-immunised pigs, which will provide a basis for the development of high-efficiency epitope vaccines.