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Maize straw deep burying into 20–40-cm layer before covering soil and plowing ridge is a useful practice to enhance soil carbon pool and make soil bacteria rich. Now, we hope to bury much more straw to reuse the huge number of them until catching the soil environmental carrying capacity in fertility, like soil organic carbon and enzyme activities. But the reasonable straw amount to return back has not been determined. Focusing on the actual output quantity of China maize straw, we designed a 7-year-term field experiment with 4 different straw deep-burying amounts of 0 t ha–1 (CK), 6 t ha–1 (SR1), 12 t ha–1 (SR2), and 18 t ha–1 (SR3). We clarified the reaction of straw amount to soil bacterial community and enzyme activities, by soil fertility, qPCR (quantitative real-time polymerase chain reaction), and Illumina high-throughput sequencing. According to the result, using 18 t ha–1 straw got the most enzyme activities of urease, cellulase, invertase, and dehydrogenase, more than others 4.71–332.38%. The 16S rRNA gene abundance of the sample with 18 t ha–1 straw has a significant rise compared to 0 t ha–1 (32.47%) and 6 t/ha (29.52%). Three domination bacteria of Proteobacteria, Actinobacteria, and Acidobacteria were sensitive to the straw using amount, and their relative abundance increased as straw amount enhancing. The microbial diversity changes finally increased the corn yield. Therefore, the more straw we used, the more abundance soil bacteria and the soil TOC we would get, in the condition of straw amount under 18 t ha–1 by deep-burying method. So we should put much more straw into soil rather than abandonment.

Waste chicken feathers are the ideal precursor for the production of low-cost N-enriched biochar. KOH-modified N-enriched biochar (KNB) containing 15.92 wt% N was successfully prepared using waste chicken feathers. The adsorption kinetics results showed that KNB had rapid Cd (2 h) and Pb (1 h) adsorption rates. The Cd and Pb adsorption capacities of KNB (the values of KF were 22.324 (Cd) and 119.654 (Pb) mg1−(1/n)·L1/n·g−1) were 7.07 and 26.52 times higher than those of the original biochar based on the adsorption isotherm results. The KNB was stable at pH 3–6 and had stronger co-adsorption capacities in double-ion systems. Based on the adsorption experiments and various characterization methods, we concluded that the primary Cd and Pb adsorption mechanisms of KNB involved electrostatic interactions, cation-π interactions, complexation, and K+ exchange. The precipitation mechanism could partially account for Pb adsorption but not for Cd adsorption. KOH modification enhanced the electronegativity of biochar and then increased the electrostatic attraction. Surface O- and N-containing functional groups were involved in Cd and Pb adsorption. Graphitic-N, oxidised-N, and O C O were the main active adsorption groups, the relative contents of which increased after KOH modification, thus increasing the Cd and Pb adsorption performance. Therefore, KNB can be used as a fast and highly efficient adsorption agent to remove Cd and Pb from wastewater containing either Cd and Pb or a combination of these two metals.

There are increasing concerns of environmental-pollution and energy issues. Herein, an exfoliation-restacking process was firstly employed to synthesize H+-restacked H+Ti2NbO7− nanosheets (HTNS), and then heated with melamine at 510 °C to obtain direct Z-scheme layered N-doped H+Ti2NbO7−/g-C3N4 (TCN) heterojunctions with an increased specific surface area. Two-dimensional (2D) g-C3N4 material was in-situ formed on the surface of HTNS to achieve a layered heterostructure between two components, which could maximize interfacial contact area and minimize interfacial distance for the efficient charge carrier separation. Simultaneously, the surface of HTNS was doped by nitrogen atoms to form visible-light-responsive N-doped HTNS. All TCNx (x = 1, 2 and 3) composites exhibited the enhanced photocatalytic activity for both hydrogen (H2) production and rhodamine B (RhB) degradation. As an optimal sample, the resulted TCN2 composite exhibited the best photocatalytic efficiency for H2 production and RhB degradation. The enhanced photocatalytic activity was assigned to the combined effects of layered heterojunction, N-doping and large specific surface area. According to trapping experiments and electron spin resonance (ESR) spectra, the holes (h+), superoxide (·O2−) and hydroxyl (·OH) radicals were responsible for photocatalytic RhB degradation and especially the ·O2− was the key active specie. A possible charge transfer pathway was analyzed in detail. This work will hopefully provide some guidance on designing Z-scheme layered heterojunction photocatalyst systems with highly photocatalytic efficiency. Direct Z-scheme layered N-doped H+Ti2NbO7−/g-C3N4 heterojunction photocatalysts were constructed by a three-step exfoliation-restacking-calcination process, showing the highly photocatalytic efficiency for H2 production and RhB degradation under visible light due to the synergistic effects of layered heterojunction, N-doping and large specific surface area.

The viscosity evolution for different temperatures was studied experimentally. A time-varying viscosity model was derived and the influence of the initial temperature on gel time was analyzed. The experimental results show that the viscosity of polymer grout increases exponentially with time. It can be divided into two phases. Before gelation, the viscosity variable quantity is very small. At the gel point, there is a sudden increase in viscosity. The initial viscosity and gel time decrease with the increasing initial temperature within a certain range, The study contributes to deepening understanding of the rheological properties of polymer grout, which can provide some references for polymer grouting construction.

Moisture is one of the important factors affecting coal spontaneous combustion. Coal with different moisture contents was prepared to obtain oxidized coal samples at different temperatures through temperature programming. In situ Fourier Transform Spectrometer was used to determine content of active functional groups in different oxidized coal samples, and to study influence of moisture form on formation and transformation of microscopic functional groups during coal spontaneous combustion. Nitrogen adsorber was used to study specific surface area of different oxidized coal samples and influence of form moisture on changes of micro-pore structure during coal spontaneous combustion. Combined with the change law of functional groups and specific surface area, microscopic action of different form moisture on coal spontaneous combustion process was discussed. The action regime of outside moisture varies with the development of coal spontaneous combustion. Different forms of moisture can promote formation of phenols, alcohols, hydroxyl groups, and carbonyl-containing compounds. Effects of moisture form and its content on change of micro-specific surface area, and on evolution of aliphatic C–H components, hydroxyl-containing compounds and carbonyl-containing compounds during spontaneous combustion of coal are different. While effect of moisture form and its content on formation and transformation of hydroxyl-containing compounds and carboxylic acid compounds are similar.

In this work, Fe–Zn catalysts were prepared, characterized, and examined for the synthesis of linear high carbon α-olefins (LAOs; C ≥ 4) directly from CO2 hydrogenation. The relationship of perform...

Direct conversion of greenhouse gas carbon dioxide (CO2) into lower olefins (ethylene, propylene and butene) provides an appealing approach to tackle CO2 emission challenges. Admixed catalysts composed of metal/metal oxides and SAPO-34 have been widely used for catalytic CO2 hydrogenation to lower olefins. However, interactions between metal/metal oxides and SAPO-34 remain obscure. Here, a novel family of admixed catalysts composed of Fe–Cu–K and SAPO-34 (Fe–Cu–K/SAPO) is developed for efficient catalytic CO2 hydrogenation to lower olefins, which can achieve 49.7% CO2 conversion and 62.9% selectivity of lower olefins, with CO selectivity

The aim of this study was to evaluate the antioxidant activity of exopolysaccharides (EPS) from Lactobacillus kimchi SR8. The EPS exhibited strong scavenging activities for 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radicals. Two EPS fractions (EPS-1 and EPS-3) exhibited higher antioxidant activities than EPS-2. Low-dose CEPS could significantly increase the activities of catalase (CAT) and glutathione peroxidase (GSH-Px) in the serum and the activities of CAT, GSH-Px and superoxide dismutase (SOD) and total antioxidant activity in the liver. Medium- and high-dose CEPS could significantly increase the activities of CAT and GSH-Px and total antioxidant activity in the serum and the activities of CAT, GSH-Px, and SOD and total antioxidant activity in the liver. High-dose CEPS significantly increased the liver index of mice and the activity of SOD in the serum. CEPS could inhibit the formation of malondialdehyde (MDA) in the serum and liver. This suggests that EPS from Lactobacillus kimchi SR8 possesses potential antioxidant activities.

Benzofuro[2,3-b]indoles, apart from their attractive biological features, constitute a novel family of electron donors for electroluminescent materials. Reported herein is the establishment of a strategy involving bimetallic catalysis to form such π-conjugated extended frameworks, specifically via the CoCl2/Cu(OTf)2-catalyzed double aerobic oxidative cycloaddition of indoles with p-hydroquinone ester. The crucial and distinct roles of the two metals salts and the alcohol solvent were clarified. This oxidation system enabled the disruption of the well-established acid-catalyzed quinone–indole [3 + 2] cycloaddition reaction favoring benzofuro[2,3-b]indolines and is superior to previously known multi-step synthetic methods involving Pd-catalyzed cross-coupling with pre-functionalized (pseudo)halides. Moreover, the photophysical properties of the product were preliminarily investigated, the results of which suggested the potential of these polycyclic heteroaromatics to be used in efficient deep-blue organic light-emitting diodes.

In recent years, the application value of low-carbon alcohols (C1-C6 alcohols) in the fuel, chemical, environmental protection and other fields has become increasingly prominent. Catalytic conversion of synthesis gas to low-carbon alcohol is one of the important ways to realize the industrial production of low-carbon alcohol. Lack of high-performance catalysts is the main reason that restricts the industrial development of producing low-carbon alcohols from synthesis gas. The construction of a dual active-center catalyst with high activity and stability, and the study of its function and catalytic mechanism have become significantly important. In this paper, the characteristics of the reaction process of syngas to low-carbon alcohols, and the catalytic mechanism and preparation methods of different catalyst systems were reviewed, which provide the basis for further research on high performance catalysts.

Secreted phospholipases A2 (sPLA2) group IIE (GIIE) is involved in several biological events, such as lipid metabolism and possibly inflammation that may mainly depend on its catalytic reaction. We previously showed that Asn21 is a critical residue that contributes to the enzymatic activity of hGIIE, but the underlying mechanism is still not clear. Here, combined with crystal structures and mutagenesis studies of the Asn21Gly mutant, we demonstrate that Asn21 acts as a switch responsible for the calcium binding and the catalytic efficiency. Our results of the atypical feature of calcium binding in hGIIE not only provide clues to understand the molecular basis of its enzymatic activity and physiological function, but also confer improved specificity for potential inhibitor design of sPLA2.

Most biomass derivatives were converted in the aqueous phase due to their high oxygen content, which, however, created a harsh environment for the catalytic reaction. In this work, Ru-based catalys...

Silicon (Si) is important for rice growth and development. Hence, it is urgent and necessary to evaluate the silicon availability of paddy soils. At present, the content of available silicon in soils is measured with 1 M acetic acid–sodium acetate (pH 4.0) buffer solution to estimate the silicon availability of paddy soils, whereas the method may not be used to evaluate silicon availability of paddy soils which are rich in calcium carbonate, or alkaline or applied with the slag. The sorption equation parameters for predicting the silicon availability of paddy soils are discussed. Isothermal adsorption with silicon equilibrium solutions (SiO2 content 0, 10, 20, 40, 60, 80, 100 mg L−1) and a pot experiment with rice plants (CK and Si treatments) were carried out with 18 paddy soils (0–20 cm) collected from major rice-producing areas in Liaoning Province of Northeast China to quantify the relationships between Si sorption parameters and soil silicon supply availability. The results showed that the equation y = bx − a could describe the Si sorption feature of 18 soils, and there were obvious differences in parameters a, b, and a/b of different soils. The y-axis intercept a of the isothermal adsorption curve linear equation indicates the content of exchangeable silicon in soils and can be used as an index representing soil silicon availability. The a value was significantly correlated with soil organic matter (OM), free iron oxide (Fed), activity of Fe oxides(Feo/Fed), and crystal/cement ratio ((Fed − Feo)/Feo), but not with pH. Parameters b and a/b were not significantly correlated with the soil physical and chemical properties. The relative silicon content (SiRE) and the relative yield of rice (YRE) increased with the a value, and the positive linear correlation between SiRE or YRE and a value reached significant p levels of 5% and 1% respectively. Isothermal adsorption equation parameter a can be used to predict the soil silicon availability, and silicon fertilizer could obviously improve the rice yield at a ≤ 126 mg kg−1 (SiO2).

In this work, periodic density functional theory (DFT) calculations were performed to investigate the CO2 activation mechanism over thermodynamically stable χ-Fe5C2 (510) and θ-Fe3C (031) facets. Four major pathways of CO2 activation were examined, including the direct dissociation of CO2 and the H-assisted intermediates of *COOH, *HCOO, and *CO + *OH. Both χ-Fe5C2 and θ-Fe3C have proven to be active for CO2 direct dissociation (Ea =0.17 eV). As for H assisted CO2 activation, the one-step formation of *CO + *OH is feasible on χ-Fe5C2 (Ea =0.24 eV). Furthermore, θ-Fe3C favors the *HCOO pathway (Ea =0.20 eV) and *CO + *OH formation (Ea = 0.11 eV), while neither phase favors the formation of *COOH. Both CO2 direct activation and H-assisted CO2 activation pathways are of vital importance under high ratio of H/C in CO2 hydrogenation reaction. This work sheds light on CO2 activation mechanism over iron carbides, improving the rational design of CO2 hydrogenation catalysts.

Background Due to their extraordinary physical and chemical properties, MoS2 nanosheets (MSNs) are becoming more widely used in nanomedicine. However, their influence on immune systems remains unclear. Materials and methods Two few-layered MSNs at sizes of 100-250 nm (S-MSNs) and 400-500 nm (L-MSNs) were used in this study. Bone marrow-derived dendritic cells (DCs) were exposed to both MSNs at different doses (0, 8, 16, 32, 64, 128 µg/mL) for 48 h and subjected to analyses of surface marker expression, cytokine secretion, lymphoid homing and in vivo T cell priming. Results Different-sized MSNs of all doses did not affect the viability of DCs. The expression of CD40, CD80, CD86 and CCR7 was significantly higher on both S-MSN- and L-MSN-treated DCs at a dose of 128 μg/mL. As the dose of MSN increased, the secretion of IL-12p70 remained unchanged, the secretion of IL-1β decreased, and the production of TNF-α increased. A significant increase in IL-6 was observed in the 128 µg/mL L-MSN-treated DCs. In particular, MSN treatment dramatically improved the ex vivo movement and in vivo homing ability of both the local resident and blood circulating DCs. Furthermore, the cytoskeleton rearrangement regulated by ROS elevation was responsible for the enhanced homing ability of the MSNs. More robust CD4+ and CD8+ T cell proliferation and activation (characterized by high expression of CD107a, CD69 and ICOS) was observed in mice vaccinated with MSN-treated DCs. Importantly, exposure to MSNs did not interrupt LPS-induced DC activation, homing and T cell priming. Conclusion Few-layered MSNs ranging from 100 to 500 nm in size could play an immunostimulatory role in enhancing DC maturation, migration and T cell elicitation, making them a good candidate for vaccine adjuvants. Investigation of this study will not only expand the applications of MSNs and other new transition metal dichalcogenides (TMDCs) but also shed light on the in vivo immune-risk evaluation of MSN-based nanomaterials.

The intrinsic exothermic reaction of coal with oxygen during low-temperature oxidation is the main heat source responsible for the self-heating and spontaneous combustion of coal. Due to the comple...

Coating and inhibitors are proposed as means to increase nitrogen (N) use, but their effects are variable. Coating and incorporation of inhibitors could be more effective. This study aimed at inves...

DNA damage and antioxidant activities of sour meat peptides were evaluated using chemiluminescence and spectroscopic methods. All sour meat peptides exhibited DNA damage protection and free radical scavenging activities against DPPH radicals, hydroxyl radicals and superoxide anions in a dose-dependent manner, and showed the strongest inhibition of hydroxyl radicals and the weakest inhibition of superoxide anion radicals. The IC50 values of sour meat peptides from inoculating fermentation were 2.11, 4.23, 0.097 and 9.85 mg/mL for the inhibition of DNA damage and scavenging capacities of DPPH radicals, hydroxyl radicals and superoxide anion radicals, respectively, and were significantly lower than those of traditional fermentation (P

A new and convenient visible-light-induced method has been developed for the synthesis of sulfonylated benzofurans via oxidative cyclization reaction of 1,6-enynes and arylsulfinic acids. This reaction was carried out under metal-free and mild conditions, in which the C–S, C-C and C = O bonds could be sequentially formed in one pot operation.

Despite the high capacity of Co3O4 employed in lithium-ion battery anodes, the reduced conductivity and grievous volume change of Co3O4 during long cycling of insertion/extraction of lithium-ions remain a challenge. Herein, an optimized nanocomposite, Co3O4/nitrogen-doped hemisphere-porous graphene composite (Co3O4/N-HPGC), is synthesized by a facile hydrothermal-template approach with polystyrene (PS) microspheres as a template. The characterization results demonstrate that Co3O4 nanoparticles are densely anchored onto graphene layers, nitrogen elements are successfully introduced by carbamide and the nanocomposites maintain the hemispherical porous structure. As an anode material for lithium-ion batteries, the composite material not only maintains a relatively high lithium storage capacity (the first discharge specific capacity can reach 2696 mA h g−1), but also shows significantly improved rate performance (1188 mA h g−1 at 0.1 A g−1, 344 mA h g−1 at 5 A g−1) and enhanced cycling stability (683 mA h g−1 after 500 cycles at 1 A g−1). The enhanced electrochemical properties of Co3O4/N-HPGC nanocomposites can be ascribed to the synergistic effects of Co3O4 nanoparticles, novel hierarchical structure with hemisphere-pores and nitrogen-containing functional groups of the nanomaterials. Therefore, the developed strategy can be extended as a universal and scalable approach for integrating various metal oxides into graphene-based materials for energy storage and conversion applications.

The exploration and fabrication of highly effective and low cost non-precious electrocatalysts are very essential for the hydrogen production industry. Herein, for the first time we constructed and prepared Ni/CoFe hydroxide and Ni/CoSe2 electrodes with hollow nanotube array structures on conductive nickel foam by a facile two-step electrodeposition method combined with a ZnO self-template strategy. The as-prepared Ni/CoFe hydroxide and Ni/CoSe2 nanotube arrays only need a relatively low overpotential of 230 mV for OER and 89 mV for HER to achieve a current density of 20 mA cm−2 and 10 mA cm−2, respectively. Specifically, an asymmetric alkaline electrolyzer has been assembled by using Ni/CoFe hydroxide as anode and Ni/CoSe2 as cathode, which requires a low overall potential of only 1.57 V at the current density of 10 mA cm−2 and displays excellent stability for 20 h. The excellent electrocatalytic performance of the electrodes benefits from the synergistic effect of the different components and the hierarchical hollow nanotube structure with abundant active sites, fast electronic transport and sufficient diffusion channels for electrolyte and gas. The work provides a feasible way to develop highly efficient, hierarchical, hollow-structured and low-cost earth-abundant catalysts for electrocatalytic water splitting applications.

To date, carbon dots (CDs) or carbon quantum dots (CQDs), considered as alternatives to conventional fluorescent materials such as organic dyes and semiconductor quantum dots (QDs), have drawn significant attention from relevant researchers due to their superior properties, including nontoxicity, biocompatibility, low cost and facile synthesis, and high photoluminescence. In particular, doping heteroatoms with CDs can not only dramatically enhance the fluorescence but also greatly improve the electronic structure and doped CDs have been successfully applied in various technological fields. Herein, this minireview summarizes recent advances on the synthesis and optical properties of doped CDs and their promising applications for photocatalysis and electrocatalysis. Finally, some challenging issues as well as future perspectives of this exciting material are discussed.

This study was conducted to investigate the effects of dietary bamboo leaf extract (BLE) on growth performance, meat quality, oxidative stability, and nuclear factor erythroid 2-related factor 2 (Nrf2) related gene expression of breast meat in broilers. A total of 576 one-day-old male Arbor Acres broilers were divided into 6 groups. The control group (CTR) was fed basal diet, while BLE1, BLE2, BLE3, BLE4, and BLE5 were fed basal diet supplemented with 1.0, 2.0, 3.0, 4.0, and 5.0 g BLE per kg feed, respectively. Compared with the CTR group, BLE2 and BLE5 increased average daily feed intake from 1 to 21 D and 22 to 42 D (P < 0.05), BLE1 and BLE2 improved average daily gain (ADG) and feed to gain ratio from 22 to 42 D (P < 0.05). Throughout the trial period, the highest body weight and favorable ADG and feed to gain ratio were observed in the BLE2 group. The drip loss at 24 h and pH at 45 min postmortem of breast meat were linearly improved by BLE supplementation (P < 0.05). Shear force was significantly lower in BLE2 and BLE3 than that in CTR group. Increasing supplementation of BLE linearly improved free radical scavenging capacity and decreased malondialdehyde content of breast meat during 12 D of storage (P < 0.05). Total antioxidant capacity and glutathione peroxidase activity were linearly increased by BLE supplementation (P < 0.05). Compared with the CTR group, the mRNA expression of Nrf2 and glutathione peroxidase in BLE3, BLE4, and BLE5 groups was significantly promoted, and glutathione S-transferase gene expression was increased in BLE2, BLE4, and BLE5 (P < 0.05). The highest (P < 0.05) heme oxygennase-1 gene expression was observed in BLE5. In conclusion, broiler supplemented with BLE improved growth performance and meat quality, BLE supplementation might activate Nrf2 pathway to alleviate lipid oxidation and increase antioxidant capacity of breast meat. The dosage of 2.0 to 3.0 g/kg BLE in broiler diet was recommanded.

For tactical missiles, sliding mode control and super-twisting algorithms have been widely studied in the area of guidance law design. However, these methods require the information of the target accelerations and the target acceleration derivatives, which is always unknown in practice. In addition, guidance laws utilizing these tools always have chattering phenomena and large acceleration commands. To solve these problems, this article introduces a barrier function based super twisting controller and expands the controller to a multivariable adaptive form. Consequently, a multivariable adaptive super-twisting guidance law based on barrier function is proposed. Moreover, the stability of the guidance law is analyzed, and the effectiveness and the robustness are demonstrated by three simulation examples. Compared with previous guidance laws using sliding mode control or super-twisting algorithm, the one proposed in this paper does not require the information of target accelerations, nor target acceleration derivatives; it has smaller super-twisting gains so that has smaller acceleration commands; it can increase and decrease the gains to follow the target accelerations and maintain the sliding mode, and it does not chatter.

To investigate the multiphase flow characteristics and improve the classification mechanism of a W-shaped hydrocyclone, this paper adopts the numerical simulation method to evaluate the effects of the particle size and density on the separation characteristics and motion behavior of particles. Forces, such as the centrifugal inertia force, pressure gradient force and fluid drag force, which control particle motion, are analyzed, and the classification mechanism of W-shaped hydrocyclones is examined in terms of the particle distribution and separation efficiency. The results indicate that the radial centrifugal inertia and pressure gradient forces in W-shaped hydrocyclones are hundreds of times the gravity force, which is the main driver of radial motion. Particle density and size changes greatly impact the movement and distribution of coarse particles, but no notable change occurs in fine particles. With increasing particle density, the cut size decreases, and the fractionation accuracy increases.

A large number of particles with small size and light density in mine water are difficult to remove by traditional separation equipment. In order to improve the efficiency of mine water treatment, a cone-plate clarifier is proposed in this paper. The particle size distribution and their fragmentation fractal dimension were studied in 15 sampling points of the cone-plate clarifier to elucidate the process of floc growth and settling. The influence of the tangential inlet velocity size distribution characteristics was also studied. The results showed that the cone-plate clarifier can effectively improve suspended solids and turbidity removal efficiency. The floc growth and settlement courses are shown in the charts. The cone-plate clarifier was divided into four zones: micro flocculation, floc growing, settlement, and exit pipe. Because the fluid enters the cone-plate clarifier tangentially, the value of the inlet velocity and the tangential velocity are equal at the inlet feed. With the increase in tangential velocity, the flocculation efficiency first increased and then decreased. Comprehensive analysis of the particle greater than 50 μm in the effluent showed that the optimal inlet was qual to 1.63 m/s. By fitting the equations, the optimal SS and turbidity removal efficiency reached the maximum values of 92.04% and 80.18% at the inlet velocity of 1.86 m/s and 1.77 m/s, respectively.

The effective cryopreservation of mesenchymal stem cells (MSCs) is indispensable to the operation of basic research and clinical transplantation. The prevalent protocols for MSC cryopreservation utilize dimethyl sulfoxide (DMSO), which is easily permeable and able to protect MSCs from cryo-injuries, as a primary cryoprotectant (CPA). However, its intrinsic toxicity and adverse effects on cell function remain the bottleneck of MSC cryopreservation. In this work, we cryopreserved human umbilical cord mesenchymal stem cells (UCMSCs) using zwitterionic betaine combined with electroporation without any addition of DMSO. Betaine was characterized by excellent compatibility and cryoprotective properties to depress the freezing point of pure water and balance the cellular osmotic stress. Electroporation was introduced to achieve intracellular delivery of betaine, intending to further provide comprehensive cryoprotection on UCMSCs. Compared with DMSO cryopreservation, UCMSCs recovered from the protocol we developed maintained the normal viability and functions and reduced the level of reactive oxygen species (ROS) that are harmful to cell metabolism. Moreover, the in vivo distribution of thawed UCMSCs was consistent with that of fresh cells monitored by a bioluminescence imaging (BLI) system. This work opens a new window of opportunity for DMSO-free MSC cryopreservation using zwitterionic compounds like betaine combined with electroporation.

Global spread of ampicillin (AMP) in the aquatic environment have attracted much attention recently. Marine anammox bacteria (MAB) have potentials in saline wastewater treatment due to their good salt tolerance. However, to date, the effect resulting from AMP on MAB is still unknown. Herein, the effect of AMP on MAB, involving microbial community evolution and genetic response, was investigated for the first time. A lab-scale reactor inoculated by MAB sludge was operated under saline condition (35 g/L) and AMP stress of different gradients. Within 200 cycles, nitrogen removal performance was monitored and sludge samples were withdrawn for high-throughput sequencing analyses and qPCR. The results confirmed that the nitrogen removal capacity of MAB declined with increasing AMP dosage, and almost collapsed at 300 mg/L AMP. The total nitrogen removal rate and specific anammox activity finally dropped to 0.17 kg N m−3 d−1 and 101.86 mg N g−1VSS d−1, respectively. Pseudoalteromonas (38.13%) dominated the reactor on Cycle 190, which formed a new symbiosis with MAB. And the emergence of oleophilic bacteria such as Colwellia (2.53%) was also observed. Moreover, antibiotic resistance genes were detected with increased abundance and diversity, indicating the AMP dosing significantly promoted microbial community evolution and genetic response.