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An Fe-abundant solid waste, fabric filter dust (FFD) was used as the starting material for the preparation of metal-doped Fe2O3 (M−Fe2O3) nanoparticles for the photocatalytic degradation of MO aqueous solution. Valuable elements including Fe, Ti, Al, Na, Si, Ca, and Mg were extracted from the dust by hydrochloric acid leaching, transformed into sediments by increasing the pH of the lixivium orderly, and converted into M−Fe2O3 nanoparticles by the sol–gel technology. The effects of pH for the precipitation process and firing temperature for the sol–gel method were investigated systematically. The M−Fe2O3 samples were characterised using X-ray diffraction, field emission scanning electron microscopy, Brunauer–Emmett–Teller analysis, UV–vis spectra, and energy dispersive spectroscopy. The performances of the dust-derived nanoparticles during photocatalytic process were appraised by visible light photodegradation of methyl orange (MO) aqueous solution, indicating that the M−Fe2O3 (M = Ti and Al) sample prepared with a precipitation pH of 4 and a firing temperature of 500 °C exhibits the most impressive photocatalytic behaviour. The product produces a degradation rate of 82.99% for 100 mL of MO solution (10 mg/L) after visible-light degradation for 180 min, which is increased from 38.94% achieved by an undoped Fe2O3 sample prepared under the same conditions.

Feed efficiency makes up a large part of sheep production, which also has a crucial impact on the economic benefits of producers. This study explores the polymorphism of

Growth traits are important economic characteristics of livestock and poultry. In the present study, the expression features of

Anthocyanins are common secondary metabolites in plants that impart red coloration to fruits and flowers. The important WRKY transcription factor family plays multifaceted roles in plant growth and development. In this study, we found a WRKY family gene, Pyrus bretschneideri WRKY75, that may be involved in anthocyanin synthesis in pear. Unlike Arabidopsis thaliana WRKY75, PbWRKY75 may be a positive regulator of anthocyanin synthesis. A transient expression assay indicated that PbWRKY75 promoted pear anthocyanin synthesis. The structural genes (PbANS, PbDFR, and PbUFGT) and positive regulators (PbMYB10 and PbMYB10b) of anthocyanin synthesis were significantly upregulated in the fruitlet skins of PbWRKY75-overexpressing "Zaosu" pears. Subsequently, yeast one-hybrid and dual-luciferase assays indicated that PbWRKY75 promoted PbDFR, PbUFGT, and PbMYB10b expression by activating their promoters. These results revealed that PbWRKY75 may promote the expression of both PbMYB10b and anthocyanin late biosynthetic genes (PbDFR and PbUFGT) by activating their promoters, thereby inducing anthocyanin synthesis in pear. This study enhanced our understanding of the mechanism of pear anthocyanin synthesis, which will be beneficial in the improvement of pear peel color.

Chiral metal-organic frameworks (chirMOFs) have been widely considered on enantioselective adsorption/separation, asymmetric catalysis, biological and nonlinear optical applications. However, chirMOFs are facing a great challenge in development of chiroptical thin films with circularly polarized luminescence (CPL) property. Here, we first report CPL thin films by encapsulating achiral lanthanide complexes Ln(acac)3 (Ln = EuaTbbGdc) into the pores of surface-coordinated chirMOF thin films (SURchirMOF) [Zn2(cam)2dabco]n with layer by layer (lbl) encapsulation strategy. Due to the unique combination of chiral porous MOF and adjustable luminescent complexes in the host-guest thin films, the obtained Ln(acac)3@SURchirMOF possess strong and tunable CPL property with high dissymmetry factors. The compared CPL and fluorescent lifetime results show that the advantage of this preparation strategy can effectively achieve energy transfer from Ln(acac)3 to SURchirMOF, resulting in an excellent CPL performance. This study not only provides a novel strategy to develop new types of chiral thin films but also offers an efficient approach for tunable chiroptical applications.

Endoperoxide-containing natural products are a group of compounds with structurally unique cyclized peroxide moieties. Although numerous endoperoxide-containing compounds have been isolated, the biosynthesis of the endoperoxides remains unclear. NvfI from Aspergillus novofumigatus IBT 16806 is an endoperoxidase that catalyzes the formation of fumigatonoid A in the biosynthesis of novofumigatonin. Here, we describe our structural and functional analyses of NvfI. The structural elucidation and mutagenesis studies indicate that NvfI does not utilize a tyrosyl radical in the reaction, in contrast to other characterized endoperoxidases. Further, the crystallographic analysis reveals significant conformational changes of two loops upon substrate binding, which suggests a dynamic movement of active site during the catalytic cycle. As a result, NvfI installs three oxygen atoms onto a substrate in a single enzyme turnover. Based on these results, we propose a mechanism for the NvfI-catalyzed, unique endoperoxide formation reaction to produce fumigatonoid A., Many endoperoxide-containing natural products have been isolated, but the biosynthesis of the endoperoxides remains unclear. Here, the authors report the structural and functional analysis of the NvfI endoperoxidase that catalyzes the formation of fumigatonoid A in the biosynthesis of novofumigatonin, and show that it does not employ tyrosyl radical in the reaction.

To investigate the prognostic value of gross tumor volume (GTV) in early-stage extranodal NK/T-cell lymphoma (ENKTCL) treated with intensity-modulated radiation therapy (IMRT) and explore the interactive effect of GTV and radiotherapy (RT) dose on locoregional recurrence (LRR).The data of 319 early-stage ENKTCL patients who underwent IMRT were reviewed retrospectively. Overall survival (OS), progression-free survival (PFS), and locoregional control (LRC) were estimated using Kaplan-Meier method and compared using the log-rank test. Cox proportional hazards regression was performed to identify independent risk factors for survival outcomes. Penalized spline regression was used to flexibly model the association of continuous predictors (GTV and RT dose) with mortality, progression, and relapse.The 5-year OS, PFS, and LRC for the entire cohort were 72.9, 64.4, and 89.9%, respectively. The risks of disease mortality, progression, and recurrence increased steadily with increasing GTV. Patients with GTV 35 mL had significantly higher 5-year OS (83.0% vs. 59.4%; P 0.001), PFS (76.7% vs. 48.4%; P 0.001), and lower 5-year cumulative LRR rate (4.9% vs. 14.5%; P = 0.004), than patients with GTV ≥ 35 mL. The risk of LRR was low with RT doses of 50-56 Gy, independent of GTV. For patients with GTV ≥ 35 mL, dose ≥ 56 Gy was not associated with decreased LRR.Larger GTV is associated with worse survival and higher LRR in early-stage ENKTCL patients treated with IMRT. A dose of 50-56 Gy may be appropriate to achieve lower risk of LRR, regardless of GTV.

IntroductionEnlarged perivascular spaces (EPVS) are ubiquitous in the elderly and have insidious onset characteristics. Its correlation with clinical symptoms is easily overlooked and controversial. The related clinical symptoms that EPVS may cause were studied using Meta-analysis.Material and methodsRelevant studies up to April 2022 were extracted from PubMed, Embase, Cochrane, OVID, and Web of Science. Odds ratios (ORs) and 95% confidence interval (CI) were used to estimate the strength of the correlation.ResultsOf the 6622 articles identified, 32 studies were eligible, enrolling a total of 19987 people. EPVS was associated with the risk of cognitive impairment (OR: 1.60, 95 % CI: 1.39- 1.81), motor impairment (OR: 2.24, 95 % CI: 1.22- 3.25), sleep disturbance (OR: 1.81, 95% CI: 1.34-2.28), depressive symptoms (OR: 1.54, 95 % CI: 1.14- 1.95), but was not significantly associated with the occurrence of stroke ( OR: 0.97, 95 % CI: 0.74-1.21). Results of subgroup analysis showed that basal ganglia (BG) EPVS were more associated with cognitive impairment (OR: 2.19, 95% CI: 1.72- 2.65) and sleep disturbance(OR: 1.74, 95 % CI: 1.20- 2.29).ConclusionsOur findings suggested that people with EPVS may be at a greater risk for cognitive impairment, motor impairment, sleep disturbance, and depressive symptoms. This will inform future treatments.

Animal growth traits are important and complex traits that determine the productivity of animal husbandry. There are many factors that affect growth traits, among which diet digestion is the key factor. In the process of animal digestion and absorption, the role of gastrointestinal microbes is essential. In this study, we transplanted two groups of sheep intestinal microorganisms with different body weights into the intestines of mice of the same age to observe the effect of fecal bacteria transplantation on the growth characteristics of the mouse model. The results showed that receiving fecal microbiota transplantation (FMT) had an effect on the growth traits of recipient mice (P 0.05). Interestingly, only mice receiving high-weight donor microorganisms showed differences. Use 16S rDNA sequencing technology to analyze the stool microorganisms of sheep and mice. The microbial analysis of mouse feces showed that receiving FMT could improve the diversity and richness of microorganisms (P 0.05), and the microbial composition of mouse feces receiving low-weight donor microorganisms was similar to that of the control group, which was consistent with the change trend of growth traits. The feces of high-weight sheep may have higher colonization ability. The same five biomarkers were identified in the donor and recipient, all belonging to Firmicutes, and were positively correlated with the body weight of mice at each stage. These results suggest that FMT affects the growth traits of receptors by remodeling their gut microflora.The rate of development of growth traits determines the productivity of sheep. Shortening the fattening cycle of sheep can effectively improve economic efficiency. Gut microbes have important effects on host growth traits. In this study, the method of fecal microbiota transplantation (FMT) was used to transplant the intestinal microbes of sheep into the mouse model, and the changes of the growth traits and intestinal microbes of the mice were observed. The results suggest that FMT can effectively affect growth traits by altering recipient gut microbes. This provides a new idea for the regulation of sheep growth traits.

Rumen microbes play an important role in the growth and development of ruminants. Differences in variety will affect the rumen community structure. The three excellent sheep breeds were selected for this study (Hu sheep, Tan sheep, and Dorper sheep) have different uses and origins. The sheep were raised on the same diet to 180 d of age in a consistent environment. 16S rDNA V3 to V4 region sequencing was used to assess the rumen microbes of 180 individuals (60 per breed). There were differences in microbial diversity among different sheep breeds (P0.05). Principal coordinate analysis showed that the three varieties were separated, but also partially overlapped. Linear discriminant analysis effect size identified a total of 19 biomarkers in three breeds. Of these biomarkers, five in Hu sheep were significantly negatively correlated with average feed conversion rate (P0.05). Six biomarkers were identified in the rumen of Dorper sheep, among which Ruminococcus was significantly positively correlated with body weight at 80 d (P0.05). In Tan sheep, Rikenellaceae_RC9_gut_group was significantly positively correlated with meat fat, and significantly positively correlated with volatile fatty acids (VFAs), such as butyric acid and isobutyric acid (P0.05). The Rikenellaceae_RC9_gut_group may regulate Tan mutton fat deposition by affecting the concentration of VFAs. Functional prediction revealed enrichment differences of functional pathways among different sheep breeds were small. All were enriched in functions, such as fermentation and chemoheterotrophy. The results show that there are differences in the rumen microorganisms of the different sheep breeds, and that the microorganisms influence the host.The rumen is the most important digestive organ of ruminants, and the rumen microflora plays an important role in the process of digestion. This study compared the differences in rumen microbes of different breeds of sheep, identified key biomarkers of each breed, and analyzed their correlation with important economic traits of sheep. The results showed that the biomarkers of various breeds were significantly correlated with key traits. Therefore, we believe that there is a link between sheep rumen microbes and the differential traits of different breeds of sheep. This provides a new idea for sheep trait improvement.

On-road remote sensing (RS) technology provides a rapid, cost-effective and non-intrusive tool to test vehicle emissions, which is gaining significant attention worldwide in recent years. RS systems are usually placed at a fixed height to test the emissions of all the passing vehicles. However, the tailpipe height varies among vehicles which may greatly affect the accuracy of RS tests. In addition, a key assumption of RS measurements is that the ratios of pollutants over carbon dioxides are constant for a given plume. So far, however, there is a lack of experimental investigation on these effects. Therefore, this study is conducted to investigate the effect of beam alignment of an RS system on the diesel emission tests. The experiments were performed using a diesel engine bench, whose emissions were tested simultaneously by a Horiba MEXA-7500 gas analyzer (serving as the comparison baseline) and a BLH-5000 on-road RS system. The experimental results show that in the three-dimensional space behind the exhaust tailpipe, the more accurate area for remote sensing technology tests along the direction of the measured light (x) is in the area 6m from the RS light source and receiver. In the direction of the exhaust discharge plume along the exhaust pipe (y), the test results do not vary much throughout the test range of 0 to 6m. In the height direction (z), when the height of the tested light is 0.3m, the area where the remote sensing technique is accurate is within the range of 0.2m to 0.4m. The relative concentration of CO tested by RS in this region has an error rate of only ± 5% with the CO concentration measured by the exhaust gas analyzer. Similarly, this indicator for HC is ± 10%, which is also smaller. Although this indicator is larger for NO, at 100%, the NO test error in this region is also the smallest in the entire test area.

Excessive fat deposition in the tail of sheep will affect its feed efficiency, which will increase the feeding cost. The purpose of this study was to identify the single nucleotide polymorphisms (SNPs) of

Lignocellulosic biorefinery based on sugar-platform has been considered as an efficient strategy to replace fossil fuel-based refinery. In the bioconversion process, pretreatment is an essential step to firstly open up lignocellulose cell wall structure and enhance the accessibility of carbohydrates to hydrolytic enzymes. However, various lignin and/or carbohydrates degradation products (e.g. phenolics, 5-hydroxymethylfurfural, furfural) are also generated during pretreatment, which severely inhibit the following enzymatic hydrolysis and the downstream fermentation process. Among them, the lignin derived phenolics have been considered as the most inhibitory compounds and their inhibitory effects are highly dependent on the source of biomass and the type of pretreatment strategy. Although liquid-solid separation and subsequent washing can remove the lignin derived phenolics and other inhibitors, this is undesirable in the realistic industrial application where the whole slurry of pretreated biomass needs to be directly used in the hydrolysis process. This review summarizes the phenolics formation mechanism for various commonly applied pretreatment methods and discusses the key factors that affect the inhibitory effect of phenolics on cellulose hydrolysis. In addition, the recent achievements on the rational design of inhibition mitigation strategies to boost cellulose hydrolysis for sugar-platform biorefinery are also introduced. This review also provides guidance for rationally designing detoxification strategies to facilitate whole slurry hydrolysis which helps to realize the industrialization of lignocellulose biorefinery.

BackgroundDysbiotic gut microbiome, genetically predisposed or chemically disrupted, has been linked with insulin-dependent diabetes (IDD) including autoimmune type 1 diabetes (T1D) in both humans and animal models. However, specific IDD-inducing gut bacteria remain to be identified and their casual role in disease development demonstrated via experiments that can fulfill Koch’s postulates.ResultsHere, we show that novel gut pathobionts in the Muribaculaceae family, enriched by a low-dose dextran sulfate sodium (DSS) treatment, translocated to the pancreas and caused local inflammation, beta cell destruction and IDD in C57BL/6 mice. Antibiotic removal and transplantation of gut microbiota showed that this low DSS disrupted gut microbiota was both necessary and sufficient to induce IDD. Reduced butyrate content in the gut and decreased gene expression levels of an antimicrobial peptide in the pancreas allowed for the enrichment of members in the Muribaculaceae family in the gut and their translocation to the pancreas. Pure isolate of one such members induced IDD in wildtype germ-free mice on normal diet either alone or in combination with normal gut microbiome after gavaged into stomach and translocated to pancreas.ConclusionThe pathobionts that are chemically enriched in dysbiotic gut microbiota are sufficient to induce insulin-dependent diabetes after translocation to the pancreas. This indicates that IDD can be mainly a microbiome-dependent disease, inspiring the need to search for novel pathobionts for IDD development in humans.

The sugar utilization efficiency and the tolerance of microorganism to inhibitors are essential for lipid production from lignocellulosic biomass. In this study, the sugar consumption and inhibitor tolerance characteristics of Trichosporon dermatis 32,903 were investigated. The results showed that the lipid yield on xylose was much lower than that on glucose, while these substrates exhibited comparative efficiency for cell growth. High inoculum size improved the tolerance of T. dermatis 32,903 to inhibitors. Based on these characteristics, sugar-targeted-utilization and cyclic fermentation strategy was developed. The tolerance of high inoculum size to inhibitors was utilized, glucose was targeted for lipid fermentation and xylose was targeted for cell growth. As a result, the lipid production efficiency was greatly enhanced. The lipid titer in hydrolysate of DLCA (Densifying Lignocellulosic biomass with Chemicals followed by Autoclave) pretreated rice straw was improved to as high as 38.4 g/L with lipid yield of 0.207 g/g consumed sugar.

Fat deposition is an important economic trait that is closely related to feed efficiency and carcass performance in livestock. In this study, the fat deposition-related traits of 1,293 Hu sheep were measured and descriptive statistical analysis was conducted. The results showed that the coefficient of variation of all fat deposition-related traits was higher than 24%. In addition, single nucleotide polymorphisms and the expression characteristics of

Cellulosic ethanol has attracted much attention as it is of great benefit to social and environmental sustainability. However, the adverse properties of lignocellulosic biomass (i.e. low bulk density, fluffy/difficult to handle, and being easily contaminated by microbes), and issues related to biomass pretreatment (i.e. high energy consumption, difficulty in scale-up and low fermentability of pretreated biomass), largely impede the commercialization of cellulosic ethanol. To address these issues, we invented a novel pretreatment method, Densifying Lignocellulosic biomass with alkaline Chemicals (DLC), and studied DLC on corn stover (CS). DLC-CS has high density and high durability, with contamination prevented and sugar fully preserved, which greatly facilitates biomass logistics. DLC-CS showed high enzymatic digestibility and high fermentability after storage. DLC-CS containing calcium hydroxide yielded 21.4 g of ethanol per 100 g of CS, which was further enhanced to 25.3 g of ethanol per 100 g of CS using a regular steam autoclave. An ethanol titer as high as 70.6 g L−1 was achieved, for the first time, without washing or detoxification of the pretreated biomass. These promising results demonstrated the great potential of DLC pretreatment for lignocellulosic biofuel production.

Two-dimensional (2D) heterostructures combine the advantageous features of different 2D materials and represent advanced electrode architectures for the development of efficient energy storage devices. However, common 2D heterostructures made by stacking different 2D sheets in van der Waals (vdW) contact impose obvious limitations in light of the energy storage performance. Here, we shed light on how heterointerface conditions exert a great influence on the electrochemical properties of the heterostructured electrode and provide an example to modulate the interface contact mode via sandwiching unique g-C3N4 mesh (m-g-C3N4). We find that such m-g-C3N4 bonded heterointerfaces can greatly increase the electrochemical activity, redox conversion kinetics and structural integrity of the constituent component (NiS2), manifesting excellent electrochemical performance with respect to vdW heterostructures. Experimental characterization along with theoretical simulations demonstrates that the synergistic effects of the mesh-bonded interfacial contact and plenty of in-between porous channels contribute to superior electrochemical performance. This study directs attention to elaborate interface engineering toward high-performance energy storage and paves the way for designing and manufacturing of advanced heterostructured electrodes for supercapacitors, batteries and other hybrid devices.

NiCoO2 (NCO) with a desirable redox activity, high lithium storage capacity and distinct rock-salt structure has gained increasing attention toward application in next-generation lithium ion batteries (LIBs) in comparison with other transition metal oxides (TMOs). However, the volumetric change and pulverization of the NCO electrode during the charge/discharge processes hugely limit its utilization in LIBs. In this study, we present a novel assembling protocol via integrating different structural configurations to address the general limitations of TMO anodes, which effectively improves the rate and cycling performance of the NCO anode. In addition, we provide an insightful understanding of the electrochemical behaviors of NCO through various ex situ characterization techniques and first-principles DFT calculations for the first time. This study reveals that the inherent rock-salt phase character of NCO could not only preserve 3D channels toward efficient ionic/electrical interdiffusion, but also retain high electrochemical reversibility during the long cycling process in comparison to the spinel NiCo2O4. Potential application of the NCO anode for LIBs has also been evaluated through assembling full cells. This study demonstrates the synergistic influences of the innate structure of NCO and elaborate composite architecture on the performance, paving the way for future design and manufacture of TMO anodes for practical applications.

R1234ze(E) is one of the new generations of refrigerants that are environment-friendly. The solubility of R1234ze(E) in the polyvinyl ether (PVE) 32 and polyol ester (POE) 32 oils was measured at a...

Helicobacter pylori is associated with gastric disorders. In this study, the anti-H. pylori capacity of natural products from "Winter Red" crabapple flowers were evaluated, including flavonoids, organic acids, terpenoids, and phenolic acids. Among these products, kaempferol showed the highest antibacterial capacity. Structure-activity relationship assays indicated that all hydroxyls contributed to the antibacterial capacity of kaempferol, with the most important being hydroxyls in the A-ring. Kaempferol had comparable anti-H. pylori capacities to clarithromycin and amoxicillin. Both kaempferol and the two antibiotics might damage the cell membrane of H. pylori. However, the RNA-sequence assay demonstrated that their antibacterial mechanisms were different. The ATP-binding cassette transporters, flagellar assembly, and fatty acid metabolism were the major pathways in H. pylori cells responding to kaempferol treatment. We suggest that crabapple containing abundant kaempferol may benefit humans by inhibiting gastric H. pylori. PRACTICAL APPLICATIONS: The anti-Helicobacter pylori capacity of natural products including flavonoids, organic acids, terpenoids, and phenolic acids from "Winter Red" crabapple flowers were evaluated in the present study. Among these products, kaempferol showed the highest antibacterial capacity. More importantly, kaempferol had comparable anti-H. pylori capacities to clarithromycin and amoxicillin, but in a manner distinct from the antibiotics. We suggest that crabapple flowers containing abundant kaempferol may be processed into various products for the patients who have gastric disorders caused by H. pylori. Or the extracted kaempferol from crabapples or other plants could be tested for the clinical treatment of gastric H. pylori.

The isonitrile moiety is an electron-rich functionality that decorates various bioactive natural products isolated from diverse kingdoms of life. Isonitrile biosynthesis was restricted for over a decade to isonitrile synthases, a family of enzymes catalyzing a condensation reaction between l-Trp/l-Tyr and ribulose-5-phosphate. The discovery of ScoE, a non-heme iron(II) and α-ketoglutarate-dependent dioxygenase, demonstrated an alternative pathway employed by nature for isonitrile installation. Biochemical, crystallographic, and computational investigations of ScoE have previously been reported, yet the isonitrile formation mechanism remains obscure. In the present work, we employed in vitro biochemistry, chemical synthesis, spectroscopy techniques, and computational simulations that enabled us to propose a plausible molecular mechanism for isonitrile formation. Our findings demonstrate that the ScoE reaction initiates with C5 hydroxylation of (R)-3-((carboxymethyl)amino)butanoic acid to generate 1, which undergoes dehydration, presumably mediated by Tyr96 to synthesize 2 in a trans configuration. (R)-3-isocyanobutanoic acid is finally generated through radical-based decarboxylation of 2, instead of the common hydroxylation pathway employed by this enzyme superfamily.

Ribosomal protein S23 (RPS23) and Heparanase (HPSE) were located on chromosome 5 and chromosome 6, respectively, which play vital roles in protein synthesis and immunity. The objective of this study was to clone RPS23 and HPSE and to detect the expression levels of RPS23 and HPSE and the polymorphisms of RPS23 and HPSE associated with the hematologic parameters by using qRT-PCR, DNA sequencing and KASPar assay. The quantitative real-time PCR (RT-qPCR) showed that the two genes were expressed widely in the ten tissues of sheep. The expression levels of RPS23 and HPSE were the highest in lung and liver, respectively. The expression levels of RPS23 and HPSE in lung and liver increased from 0 to 3 months, decreased from 3 to 6 months, respectively. Furthermore, two mutations g.720 A G and g.1077 G A were detected in the RPS23 and HPSE, respectively, which were confirmed to be significantly associated with hematologic parameters. These results supported RPS23 g.720 A G and HPSE g.1077 G A as genetic markers of sheep.

Waelz slag, which is a Fe-bearing hazardous waste, was applied as the raw material in the synthesis of M-Fe3O4@Fe2O3 (M = Al, Zn, Cu, and Mn) nanoparticles, which are potential photocatalysts. Through acidolysis, 97.23% of Fe and most of the valuable metals were extracted from this slag. Using sol-gel processes, designed Fe3O4@Fe2O3 nanoparticles doped with multiple elements were systematically synthesised and characterised using X-ray diffraction, field emission scanning electron microscopy, electron diffraction spectroscopy, transmission electron microscopy, and Brunauer–Emmett–Teller analysis. The photocatalytic activities of the synthesised particles and undoped Fe2O3 nanoparticles were compared through photocatalytic methyl orange degradation experiments under UV and simulated solar light. The results indicated that all of the slag-derived nanoparticles gave improved photocatalytic performances compared to the undoped sample, and the M-Fe3O4@Fe2O3 (M = Al, Zn, and Cu) sample exhibited the best photocatalytic activity. The enhancement can be attributed to grain refinement, doping, and the formation of a typical Fe3O4@Fe2O3 core-shell structure.

Heterochiral coupling is favoured in abiotic peptide bond formation, whereas biotic peptide bond formation is dominated by homochiral coupling. Here, we report that heterochiral coupling is a rather general paradigm in the head-to-tail macrolactamization of non-ribosomal peptide biosynthesis. The canonical cis-acting offloading cyclases, such as type I thioesterase (TE) and terminal condensation-like domains, catalyse head-to-tail macrolactamization between N- and C-terminal residues with d- and l-configurations, respectively. In contrast, the penicillin-binding protein-type TEs, a recently identified family of trans-acting cyclases, couple heterochiral residues with complementary stereoselectivity to the canonical one. Thus, a suite of cis- and trans-TE non-ribosomal peptide synthetases could overcome the stereochemical constraints present in heterochiral head-to-tail macrolactam formation in bacterial non-ribosomal peptide biosynthesis. Furthermore, we provide the structural rationale for the C-terminal stereoselectivity of non-canonical offloading cyclases. Penicillin-binding protein-type TEs with broad substrate specificity are potentially applicable as biocatalysts and genetic tools for synthetic biology. Penicillin-binding protein-type thiosterases are recently discovered trans-acting enzymes constructing macrocycles during non-ribosomal peptide biosynthesis. Now, their synthetic potential is explored and a protein crystal structure provides insights into their unusual stereochemical requirement.

High quality graphene (HQG) offers unconventional properties and is desirable for a variety of applications. However, facile solution processing (especially in water) and chemical bonding of functional components with the aim of achieving high-yield, green, and controllable synthesis of advanced graphene materials are of great concern. Herein, the surface chemistry of HQG is effectively tailored using a hydrophobic-driven assembly of cellulose macromolecules (CM) with various functionalities. In contrast to bulk or nanocellulose modifiers, surface engineering of HQG with densely carboxyl grafted CM renders stable aqueous graphene colloids via electrostatic repulsion. It also enables the use of efficient, low-cost, aqueous-phase synthetic techniques to create new HQG-based materials and devices. Highly exposed and reactive carboxyl and hydroxyl groups lead to in situ formation of evenly distributed Co3O4 nanoparticles on HQG sheets (HQG-COOH-Co3O4). We further demonstrate the potential application of two-dimensional HQG-COOH-Co3O4 heterostructures as supercapacitor electrodes with high power and energy density.

Lithium-sulfur (Li-S) batteries are one of the most promising candidates for meeting the emerging market demands for energy storage, and have the advantages including high energy density and low cost. However, the practical application of Li-S batteries is hindered by the lithium polysulfide (LiPS) shuttle, which induces low sulfur utilization and unsatisfactory capacity retention. To address this problem, recent studies have focused on improving the transformation of LiPS into insoluble Li2S2/Li2S through methods beyond physical or chemical adsorption. Nevertheless, the commonly used host materials have limited ability to simultaneously trap and propel redox transfer of LiPS. Herein, the bottom-up construction of new organic-inorganic hybrid frameworks for sulfur cathodes is proposed to fundamentally restrict LiPS dissolution and enhance their electrochemical transformation. The synergistic integration of organic cellulose networks and inorganic ZIF-derivatives caused highly efficient LiPS mediators to suppress the shuttle effect and retain electrode stability. The resulting RCE-Co3O4@G-S cathode materials delivered a stable capacity of 726.5 mA h g-1 at 0.2 C after 350 cycles, with a very low fading rate of 0.026% per cycle and a high coulombic efficiency of 98.9%.

DNA tetrahedral nanomaterials have been widely used in the fields of biosensing, drug delivery, bioimaging and separation analysis because of their high stability, good biocompatibility and easy modification. Through different designs, specific functional molecules can be modified at DNA tetrahedral vertices, DNA tetrahedral cage structures, DNA double helix structures or DNA tetrahedron arms. The advantages of the materials combine well with the specific functions of the active molecules. This paper reviewed the development of DNA nanotechnology, and introduced four different functional modifications of DNA tetrahedron nanomaterials and their research status.

A facile, controllable and environmentally friendly method for fabricating a novel polysaccharide–silica composite stationary phase (SiO2@(HA-CS)12) was developed in this report. Two natural polysaccharides (hyaluronan acid and chitosan) were controllably coated on the silica surface using a layer-by-layer assembly technique, and then the polysaccharide shell was chemically cross-linked to improve the stability. The column efficiency of the SiO2@(HA-CS)12 column reached 74 000 plates per m in HILIC mode and 20 100 plates per m in IEC mode, which indicates great potential for separating polar and charged samples.

Background Decrease in anthocyanin content results in the loss of red color in leaves, petals and receptacles during development. The content of anthocyanin was affected by the biosynthesis and degradation of anthocyanin. Compared with the known detailed mechanism of anthocyanin biosynthesis, the degradation mechanism is not fully investigated. It is vital to study the degradation mechanism of anthocyanin in pear for promoting the accumulation of anthocyanin and inhibiting the red fading in pear. Results Here, we reported that laccase encoded by PbLAC4-like was associated with anthocyanin degradation in pear. The expression pattern of PbLAC4-like was negatively correlated with the content of anthocyanin during the color fading process of pear leaves, petals and receptacles. Phylogenetic analysis and sequence alignment revealed that PbLAC4-like played a vital role in anthocyanin degradation. Thus, the degradation of anthocyanin induced by PbLAC4-like was further verified by transient assays and prokaryotic expression. More than 80% of anthocyanin compounds were degraded by transiently over-expressed PbLAC4-like in pear fruitlet peel. The activity of crude enzyme to degrade anthocyanin in leaves at different stages was basically consistent with the expression of PbLAC4-like. The anthocyanin degradation ability of prokaryotic induced PbLAC4-like protein was also verified by enzyme activity assay. Besides, we also identified PbMYB26 as a positive regulator of PbLAC4-like. Yeast one-hybrid and dual luciferase assay results showed that PbMYB26 activated PbLAC4-like expression by directly binding to the PbLAC4-like promoter. Conclusions Taken together, the PbLAC4-like activated by PbMYB26, was involved in the degradation of anthocyanin, resulting in the redness fading in different pear tissues.

Graphene is a superior active material in energy storages due to its exceptional properties, such as high specific area, high electrical conductivity, and excellent chemical stability. Currently, the large-scale preparation of graphene powder constitutes a research hotspot. Usually, the as-prepared graphene powders was used directly leading to poor dispersion which greatly affects the electrode's properties. Thus, one crucial application problem which needs to be solved urgently is how to obtain ultrahigh concentration and stable dispersion of single-layer graphene. Therefore, in this work, we prepared successfully a single-layer reduced graphene oxide (RGO) powder by expansion-oxidation-expansion process. The RGO paste was obtained through high-speed ball-milling technology, offering ultrahigh concentration (27 mg/mL) and high stability. Meanwhile, the above-mentioned paste be combined with LiFePO4 (LFP) towards obtaining cathode materials for Li-ion batteries. LFP@RGO demonstrated an excellent discharge capacity of 168.3 mA h g−1 at 0.1 C, and maintained 99.9% of capacity after 100 cycles at 0.5 C. Herein, we demonstrated an effective way to prepare the ultrahigh concentration, and stable dispersion of single-layer graphene paste in the field of energy storage and conversion.