Enhancing the Lithium Storage Performance of the Nb2O5 Anode via Synergistic Engineering of Phase and Cu Doping.

Nb2O5 has been viewed as a promising anode material for lithium-ion batteries by virtue of its appropriate redox potential and high theoretical capacity. However, it suffers from poor electric conductivity and low ion diffusivity. Herein, we demonstrate the controllable fabrication of Cu-doped Nb2O5 with orthorhombic (T-Nb2O5) and monoclinic (H-Nb2O5) phases through annealing the solvothermally presynthesized Nb2O5 precursor under different temperatures in air, and the Cu doping amount can be readily controlled by the concentration of the precursor solution, whose effect on the lithium storage behaviors of the Cu-doped Nb2O5 is thoroughly investigated. H-Nb2O5 shows obvious redox peaks (Nb5+/Nb4+ and Nb4+/Nb3+) with much higher capacity and better cycling stability than those for the widely investigated T-Nb2O5. When introducing appropriate Cu doping, the optimized H-Cu0.1-Nb2O5 electrode shows greatly enhanced conductivity and lower diffusion barrier as revealed by the theoretical calculations and electrochemical characterizations, delivering a high reversible capacity of 203.6 mAh g-1 and a high capacity retention of 140.8 mAh g-1 after 5000 cycles at 1 A g-1, with a high initial Coulombic efficiency of 91% and a high rate capacity of 144.2 mAh g-1 at 4 A g-1. As a demonstration for full-cell application, the H-Cu0.1-Nb2O5||LiFePO4 cell displays good cycling performance, exhibiting a reversible capacity of 135 mAh g-1 after 200 cycles at 0.2 A g-1. More importantly, this work offers a new synthesis protocol of the monoclinic Nb2O5 phase with high capacity retention and improved reaction kinetics.

Conformal Conversion of Polyphosphazene@Sb2MoO6 Nanowires to N/S-Doped/Carbon-Coated SbPO4/MoOx for High-performance Lithium Storage.

Alloy-type antimony (Sb) and conversion-type molybdenum (Mo) anodes have attracted extensive attention in the application of lithium-ion batteries (LIBs) owing to their high theoretical capacity. In this study, Sb2MoO6 nanowires are prepared via a hydrothermal method and assessed their thermal behavior upon heat treatment, observing an intriguing transformation from nanowire to Sb2O3/MoOx nanosheets. To enhance structure stability, the Sb2MoO6 nanowires are successfully coated with a polyphosphazene layer (referred to as PZS@Sb2MoO6), which not only preserved the nanowires form but also yielded N/S co-doped carbon-coated SbPO4/MoOx (NS-C@SbPO4/MoOx) nanowires following annealing in an inert environment. This composite benefits from the stable PO4 3- anion that serve as a buffer against volume expansion and form a Li3PO4 matrix during cycling, both of which substantially bolster ion transport and cycle endurance. Doping with heteroatoms introduces numerous oxygen vacancies, augmenting the number of electrochemically active sites, and carbon integration considerably enhances the electronic conductivity of the electrode and alleviates the volume-change-induced electrode pulverization. Employed as anode materials in LIBs, the NS-C@SbPO4/MoOx electrode exhibits remarkable cycling performance (449.8 mA h g-1 at 1000 mA g-1 over 700 cycles) along with superior rate capability (394.2 mA h g-1 at 2000 mA g-1).

Encapsulation of Titanium Disulfide into MOF-Derived N,S-Doped Carbon Nanotablets Toward Suppressed Shuttle Effect and Enhanced Sodium Storage Performance.

Titanium disulfide (TiS2 ) is a promising anode material for sodium-ion batteries due to its high theoretical capacity, but it suffers from severe volume variation and shuttle effect of the intermediate polysulfides. To overcome the drawbacks, herein the successful fabrication of TiS2 @N,S-codoped C (denoted as TiS2 @NSC) through a chemical vapor reaction between Ti-based metal-organic framework (NH2 -MIL-125) and carbon disulfide (CS2 ) is demonstrated. The C─N bonds enhance the electronic/ionic conductivity of the TiS2 @NSC electrode, while the C─S bonds provide extra sodium storage capacity, and both polar bonds synergistically suppress the shuttle effect of polysulfides. Consequently, the TiS2 @NSC electrode demonstrates outstanding cycling stability and rate performance, delivering reversible capacities of 418/392 mAh g-1 after 1000 cycles at 2/5 A g-1 . Ex situ X-ray photoelectron spectroscopy and transmission electron microscope analyses reveal that TiS2 undergoes an intercalation-conversion ion storage mechanism with the generation of metallic Ti in a deeper sodiation state, and the pristine hexagonal TiS2 is electrochemically transformed into cubic rock-salt TiS2 as a reversible phase with enhanced reaction kinetics upon sodiation/desodiation cycling. The strategy to encapsulate TiS2 in N,S-codoped porous carbon matrices efficiently realizes superior conductivity and physical/chemical confinement of the soluble polysulfides, which can be generally applied for the rational design of advanced electrodes.

Atmospheric organic nitrogen deposition around the Danjiangkou Reservoir: Fluxes, characteristics and evidence of agricultural source.

Dissolved organic nitrogen (DON) deposition was the substantial component of dissolved total nitrogen (DTN) deposition in the world's nitrogen deposition hot spots areas. However, the information on the importance for DON deposition and its sources was still scarce, which limited the comprehensive assessment of the ecological threat from nitrogen deposition. Six sampling sites around the Danjiangkou Reservoir were set up to collect the dry and wet deposition samples from October 2017 to September 2021. The results showed that dry and wet DTN deposition averaged 34.72 kg ha-1 yr-1 and 22.27 kg ha-1 yr-1, respectively. Dry NH4+-N, NO3--N and DON deposition averaged 14.28 kg ha-1 yr-1, 5.91 kg ha-1 yr-1 and 14.53 kg ha-1 yr-1, respectively. Wet NH4+-N, NO3--N and DON deposition averaged 11.14 kg ha-1 yr-1, 3.89 kg ha-1 yr-1and 7.24 kg ha-1 yr-1, respectively. The contributions of DON to DTN were 41.85% (in dry deposition) and 32.50% (in wet deposition), respectively. Dry DON deposition varied between 26.44 kg ha-1 yr-1 and 9.11 kg ha-1 yr-1, and significantly differed among six sampling sites (P < 0.05). The different intensity of agricultural activities disturbance at the sampling sites was the important reason for the spatial variations of DON deposition. DON deposition was significantly correlated with ammonium nitrogen (NH4+-N) deposition (P < 0.05). According to the results of positive matrix factorization (PMF) model, agriculture source contributed significantly to the DON deposition, the contributions at six sampling sites ranged from 45.8% to 73.7% in dry deposition, and from 56.8% to 81.6% in wet deposition. In summary, our findings found that agricultural activities were the important factors influencing the spatial patterns of DON deposition around Danjiangkou Reservoir and provided new evidence for the anthropogenic source of DON deposition in China.

Constrained DRL for Energy Efficiency Optimization in RSMA-Based Integrated Satellite Terrestrial Network.

To accommodate the requirements of extensive coverage and ubiquitous connectivity in 6G communications, satellite plays a more significant role in it. As users and devices explosively grow, new multiple access technologies are called for. Among the new candidates, rate splitting multiple access (RSMA) shows great potential. Since satellites are power-limited, we investigate the energy-efficient resource allocation in the integrated satellite terrestrial network (ISTN)-adopting RSMA scheme in this paper. However, this non-convex problem is challenging to solve using conventional model-based methods. Because this optimization task has a quality of service (QoS) requirement and continuous action/state space, we propose to use constrained soft actor-critic (SAC) to tackle it. This policy-gradient algorithm incorporates the Lagrangian relaxation technique to convert the original constrained problem into a penalized unconstrained one. The reward is maximized while the requirements are satisfied. Moreover, the learning process is time-consuming and unnecessary when little changes in the network. So, an on-off mechanism is introduced to avoid this situation. By calculating the difference between the current state and the last one, the system will decide to learn a new action or take the last one. The simulation results show that the proposed algorithm can outperform other benchmark algorithms in terms of energy efficiency while satisfying the QoS constraint. In addition, the time consumption is lowered because of the on-off design.

Introducing Hybrid Defects of Silicon Doping and Oxygen Vacancies into MOF-Derived TiO2-X @Carbon Nanotablets Toward High-Performance Sodium-Ion Storage.

Titanium dioxide (TiO2 ) is a promising anode material for sodium-ion batteries (SIBs), which suffer from the intrinsic sluggish ion transferability and poor conductivity. To overcome these drawbacks, a facile strategy is developed to synergistically engineer the lattice defects (i.e., heteroatom doping and oxygen vacancy generation) and the fine microstructure (i.e., carbon hybridization and porous structure) of TiO2 -based anode, which efficiently enhances the sodium storage performance. Herein, it is successfully realized that the Si-doping into the MIL-125 metal-organic framework structure, which can be easily converted to SiO2 /TiO2-x @C nanotablets by annealing under inert atmosphere. After NaOH etching SiO2 /TiO2-x @C which contains unbonded SiO2 and chemically bonded SiOTi, thus the lattice Si-doped TiO2-x @C (Si-TiO2-x @C) nanotablets with rich Ti3+ /oxygen vacancies and abundant inner pores are developed. When examined as an anode for SIB, the Si-TiO2-x @C exhibits a high sodium storage capacity (285 mAh g-1 at 0.2 A g-1 ), excellent long-term cycling, and high-rate performances (190 mAh g-1 at 2 A g-1 after 2500 cycles with 95.1% capacity retention). Theoretical calculations indicate that the rich Ti3+ /oxygen vacancies and Si-doping synergistically contribute to a narrowed bandgap and lower sodiation barrier, which thus lead to fast electron/ion transfer coefficients and the predominant pseudocapacitive sodium storage behavior.

Polyphosphazene-derived P/S/N-doping and carbon-coating of yolk-shelled CoMoO4 nanospheres towards enhanced pseudocapacitive lithium storage.

Transition metal oxides as potentialanodes of lithium-ion batteries (LIBs) possess high theoretical capacity but suffer from large volume expansion and poor conductivity. To overcome these drawbacks, we designed and fabricated polyphosphazene-coated yolk-shelled CoMoO4 nanospheres, in which polyphosphazene with abundant C/P/S/N species was readily converted into carbon shells and provided P/S/N dopants. This resulted in the formation of P/S/N co-doped carbon-coated yolk-shelled CoMoO4 nanospheres (PSN-C@CoMoO4). The PSN-C@CoMoO4 electrode exhibits superior cycle stability of 439.2 mA h g-1at 1000 mA g-1after 500 cycles and rate capability of 470.1 mA h g-1at 2000 mA g-1. The electrochemical and structural analyses reveal that PSN-C@CoMoO4 with yolk-shell structure, coated with carbon and doped with heteroatom not only greatly enhances the charge transfer rate and reaction kinetics, but also efficiently buffers the volume variation upon lithiation/delithiation cycling. Importantly, the use of polyphosphazene as coating/doping agent can be a general strategy for developing advanced electrode materials.

Fluxes, characteristics and influence on the aquatic environment of inorganic nitrogen deposition in the Danjiangkou reservoir.

Atmospheric reactive nitrogen (Nr) deposition has caused serious damage to the terrestrial and freshwater ecosystems and also affected human health. Measuring temporal and spatial characteristics of Nr deposition is critical for proposing control strategy to decrease negative effects. We investigated the fluxes of ammonia nitrogen (NH4-N) and nitrate nitrogen (NO3-N) in both dry and wet deposition from October 2017 to September 2020 at six sites around the Danjiangkou reservoir. The results showed that the fluxes of dissolved inorganic nitrogen (DIN) decreased from 24.39 kg ha-1 yr-1 (2017-2018) to 16.11 kg ha-1 yr-1 (2019-2020) for dry deposition, and from 19.71 kg ha-1 yr-1 (2017-2018) to 12.29 kg ha-1 yr-1 (2019-2020) for wet deposition. Both NH4-N and NO3-N in wet deposition exhibited significant (P < 0.01) differences among four seasons, and were markedly influenced by the precipitation. The fluxes of NO3-N deposition showed significant (P < 0.05) difference among six samples. Dry component contributed more to total DIN deposition, and NH4-N was the dominant species in DIN deposition. The ratios of NH4-N to NO3-N in four seasons were higher than 2. A positive matrix factorization (PMF) model estimated that the factors of agriculture and fossil fuel combustion accounted for 77.1 % and 17.0 %, respectively, to the dry NH4-N deposition; and that the factors of agricultural source and biomass burning accounted for 56.2 % and 21.1 %, respectively, to the wet NH4-N deposition. The DIN deposition contributed to 7.7 % of the total Nr input into the reservoir, and the contribution of DIN deposition to the increase in the nitrogen concentration (ΔN) of the Danjiangkou reservoir was 0.13 mg L-1 yr-1. The dry DIN deposition was significantly correlated with the concentration of nitrogen in Danjiangkou reservoir (P < 0.01). This study suggested that the control measures of agricultural activity were essential to reduce Nr deposition, and to decrease the potential risks of water pollution in the reservoir. Furthermore, more long-term study is necessary to understand the relation between control measures, Nr deposition and water quality.

A 1-year longitudinal study on COVID-19 convalescents reveals persistence of anti-SARS-CoV-2 humoral and cellular immunity.

The immune memory of over 400 million COVID-19 convalescents is not completely understood. In this integrated study, we recorded the post-acute sequelae symptoms and tested the immune memories, including circulating antibodies, memory B cell, and memory CD4 or CD8 T cell responses of a cohort of 65 COVID-19 patients over 1-year after infection. Our data show that 48% of them still have one or more sequelae symptoms and all of them maintain at least one of the immune components. The chances of having sequelae symptoms or having better immune memory are associated with peak disease severity. We did four-time points sampling per subject to precisely understand the kinetics of durability of SARS-CoV-2 circulating antibodies. We found that the RBD IgG levels likely reach a stable plateau at around 6 months, albeit it is waning at the first 6 months after infection. At 1-year after infection, more than 90% of the convalescents generated memory CD4 or CD8 T memory responses, preferably against the SARS-CoV-2 M peptide pool. The convalescents also have polyfunctional and central memory T cells that could provide rapid and efficient response to SARS-CoV-2 re-infection. Based on this information, we assessed the immune protection against the Omicron variant and concluded that convalescents should still induce effective T cell immunity against the Omicron. By studying the circulating antibodies and memory B or T cell responses to SARS-CoV-2 in an integrated manner, our study provides insight into the understanding of protective immunity against diseases caused by secondary SARS-CoV-2 infection.

Highly luminescent N-doped carbon dots as a fluorescence detecting platform for Fe3+ in solutions and living cells.

Iron (Fe3+) is one of the most essential elements in the human body; deficiency or overdose of Fe3+ may have adverse effects on human health and immunity. Hence, it is essential to establish a sensitive and selective method for ion detection. In this study, novel green fluorescent N-doped carbon dots (N-CDs) were prepared with caffeic acid as the carbon source via a simple hydrothermal method. The solution of the as-prepared N-CDs exhibits 21.5% quantum yield, good salt stability, excellent water solubility, low cytotoxicity and good photobleaching resistance. The N-CDs can be used as a fluorescent probe for the detection of Fe3+ ions in aqueous solutions and bioimaging in living cells.

Fabrication of green poly(vinyl alcohol) nanofibers using natural deep eutectic solvent for fast-dissolving drug delivery.

Fast-dissolving drug delivery systems are essential to drug delivery owing to the enhanced drug solubility, controlled drug concentration, target and rapid drug delivery. In this study, we developed fast-dissolving drug delivery systems using honey and acetylsalicylic acid-embedded poly(vinyl alcohol) (PVA) nanofibers based on natural deep eutectic solvent (DES). The efficacy of our fast-dissolving drug delivery system was tested by incorporating honey and acetylsalicylic acid in the PVA nanofibers. Firstly, the morphology and structure of the functional PVA-DES nanofibers (PVA-DES-honey and PVA-DES-ASA) were observed and analyzed, which proved the successful preparation of functional PVA-DES nanofibers. NIH/3T3 and HepG2 cells incubated on the nanofiber had more than 90% of cell viability, suggesting our materials were biocompatible and non-toxic. The nanofiber materials dissolved rapidly in artificial saliva solutions, suggesting potential use of our materials for fast dissolving drug delivery in oral cavities. The honey incorporated PVA nanofiber (PVA-DES-honey) showed a total bacterial reduction of 37.0% and 37.9% against E. coli and S. aureus, respectively, after 6 hour incubation in bacterial cultures. Furthermore, in vivo study proved that the PVA-DES-honey nanofibers accelerated the wound healing process, and they improved the wound healing rate on rat skin to 85.2% after 6 days of surgery, when compared to the control PVA (68.2%) and PVA-DES (76.3%) nanofibers. Overall, the nanofiber materials reported in our study showed potential as a green and biocompatible fast-dissolving drug delivery system and can be used for pharmaceutical fields, such as antibacterial wound dressing and oral ulcer stickers.

In situ assembly of well-dispersed Ag nanoparticles on the surface of polylactic acid-Au@polydopamine nanofibers for antimicrobial applications.

Nanofibrous membranes which exhibit bacteriostatic functions are a good strategy to prevent microorganisms from adhering to the surface of biomaterials. Here, we report the synthesis of such a nanofibrous membrane which can be applied to biological coatings to reduce bacteriostatic functionality. Ascorbic acid was utilized to reduced chloroauric acid to gold nanoparticles (AuNPs). Dopamine was then polymerized upon AuNP surfaces by ultrasound-assistance, to synthesize core-shell structured polydopamine-coated AuNPs (Au@PDA NPs). The Au@PDA NPs were then mixed with polylactic acid (PLA) for electrospinning into cylindrical nanofibers (136.6 nm diameter). PLA-Au@PDA nanofibrous membranes were finally immersed in silver nitrate for in situ reduction into a silver nanoparticle (AgNP) coating to yield PLA-Au@PDA@Ag nanofibers. The PLA-Au@PDA@Ag nanofibers were characterized based on field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and contact angle analyses. The antibacterial properties of the PLA-Au@PDA@Ag nanofibers were examined based on the optical density absorbance of bacterial cell suspensions, traditional colony plate counts, zone inhibition analyses, and field-emission scanning electron microscopy. Escherichia coli and Staphylococcus aureaus respectively served as Gram negative and positive bacterial models of industrial relevance. The data conclusively illustrates the antimicrobial and biomedical applications of PLA-Au@PDA@Ag nanofibers.

Thermostable properties of the equine infectious anemia virus nucleocapsid protein NCp11.

Retroviral nucleocapsid (NC) proteins are multifunctional nucleic acid binding proteins, playing critical roles in essentially every step of the viral replication cycle. As a small, basic protein, NC contains one or two highly conserved zinc-finger domains, each having an invariant CCHC motif, flanked by basic residues. In this study, we report for the first time, to our knowledge, the thermostable property of equine infectious anemia virus (EIAV) NCp11. About 43% of purified NCp11 remained soluble after incubation at 100 °C for 60 min, and heat-treated NCp11 maintained its abilities to bind to the E. coli RNA and the EIAV packaging signal sequence. At a very high degree of sequence occupancy, NCp11 inhibited first-strand cDNA synthesis catalyzed by either a commercial or the purified EIAV reverse transcriptase, and heat-treated NCp11 still inhibited the first-strand cDNA synthesis. We also found that protein concentrations, at a range from 0.1 to 0.9 µg/µl, have not affected the NCp11 thermostability significantly. However, NCp11 at acidic pH was more thermostable. Our findings highlight a new feature of the NC protein. Detailed understanding of NC's properties and functions will facilitate the development of effective and rational therapeutic strategies against retroviruses.

In situ colorimetric detection of glyphosate on plant tissues using cysteamine-modified gold nanoparticles.

Monitoring the levels of pesticides on plant tissues is important for achieving effective protection of crops after application, as well as ensuring low levels of residues during harvest. In this study, a simple, rapid, and fieldable colorimetric method for detecting the pesticide glyphosate (Gly) on the plant tissues in situ using cysteamine-modified gold nanoparticles (AuNPs-Cys) has been developed. The aggregation of AuNPs-Cys in the presence of Gly results in a consequent color change from red to blue (or purple), which could be observed visually on the surface of plant tissues. With the naked eye, we successfully detected Gly spiked on the surface of spinach, apple, and corn leaves in situ. Further verification and quantification were achieved using surface-enhanced Raman spectroscopy (SERS) which uses AuNPs-Cys as the substrate. Moreover, application of this method was demonstrated through the evaluation of the Gly distribution on plant tissues which could greatly facilitate the development of precision agriculture technology.

Lecithin doped electrospun poly(lactic acid)-thermoplastic polyurethane fibers for hepatocyte viability improvement.

The development of hepatocyte cultures in vitro holds great significance in the study of bioartificial liver support systems. Electrospun fiber cultures have received widespread attention as an effective method to culture hepatocytes in vitro. Polylactic acid (PLA) -a synthetic polymer with high biocompatibility and biodegradability- is widely used to fabricate electrospun fibers in the biomedical field. However, the use of PLA is limited in cell cultures due to its brittleness, strong hydrophobicity, and lack of biologically active functional groups. In this study, thermoplastic polyurethane (TPU) and lecithin (Lec) were used to modify PLA by spiking them into the PLA electrospun solution in attempt to establish a suitable fiber scaffold for hepatocyte culture in bioreactors. TPU and lecithin incorporation into PLA increases the flexibility, hydrophilicity, and biologically active groups of the fibers which further promotes the growth, proliferation, and viability of hepatocytes. The morphology, wettability, and biocompatibility of the as-prepared PLA-TPU-Lec fibers were carefully characterized. The results showed that the PLA-TPU-Lec fibers possessed favorable morphology and hydrophilicity, as well as high biocompatibility ability. HepG2 cells on the PLA-TPU-Lec fibers and tissue culture plates (TCP) were exposed to hepatotoxins for 24 h and we found that HepG2 cells on the PLA-TPU-Lec fibers had higher viability than cells on TCP. The PLA-TPU-Lec fibers are therefore expected to be used in vitro for hepatocyte culture to improve cellular activity in artificial liver bioreactors.

The reduction in FOXA2 activity during lung development in fetuses from diabetic rat mothers is reversed by Akt inhibition.

Hyperglycemia during pregnancy is associated with fetal lung development disorders and surfactant protein (SP) deficiency. Here, we examined the role of FOXA2 and Akt signaling in fetal lung development during diabetic pregnancy. Sprague-Dawley rats were injected with streptozocin (STZ) during pregnancy to induce diabetes (DM). DM-exposed fetal lungs exhibited reduced numbers of alveoli, irregularities in the appearance and thickness of the alveolar septum, increased levels of glycogen and lipids in type II alveolar epithelial cells, fewer microvilli and mature lamellar bodies, and swollen mitochondria. SP-B and SP-C in DM amniotic fluid and DM lungs were lower than in the control group (P < 0.05). DM lung nuclear FOXA2 was lower compared with the control group (P < 0.05), but p-FOXA2 was higher (P < 0.05). In murine lung epithelial (MLE) 12 cells, p-AKT levels were increased by high glucose/insulin, but decreased by the Akt inhibitor MK2206 (P < 0.05). Expression of nuclear FOXA2 was increased by MK2206 compared with the high glucose/insulin group (P < 0.05). These results suggest that maternal diabetes induces fetal lung FOXA2 phosphorylation through the Akt pathway, and also affects the maturation of alveolar epithelial cells and reduces levels of SP-B and SP-C in the fetal lungs. An Akt inhibitor reversed the changes in SP expression in vitro.

Expression of Lung Surfactant Proteins SP-B and SP-C and Their Regulatory Factors in Fetal Lung of GDM Rats.

This study investigated the expression of lung surfactant proteins (SP-B and SP-C), and regulatory factors [forkhead box A2 (FOXA2) and nitrolyogenic FOXA2 (N-FOXA2)] in the fetal lung of rats with gestational diabetes mellitus (GDM) in order to study the mechanism of pulmonary dysplasia. The rat GDM model was established by using streptozotocin intraperitoneally in the first stage of pregnancy. There were 10 rats in the GDM group, and 10 healthy rats in normal control group without any treatment. Fetal lungs of two groups were taken at day 21 of pregnancy. Blood glucose levels of maternal rats and fetal rats were measured by Roche blood glucose meter. The histological changes in the fetal lung were observed under the light microscope in both groups. The SP-B, SP-C and FOXA2 were determined in the fetal lung of two groups immunohistochemically. The expression levels of SP-B, SP-C, total FOXA2, FOXA2 in nucleus (n-FOXA2), N-FOXA2 proteins were detected by Western blotting, and the relative expression levels of SP-B, SP-C, FOXA2 mRNA in the fetal lung of two groups were detected by RTPCR. The results showed that blood glucose levels of maternal rats and fetal rats in GDM group were higher than those in control group. The light microscope revealed fetal lung development retardation in GDM group. The expression of SP-B and SP-C in GDM group was significantly reduced as compared with control group (P<0.05). As compared with control group, the n-FOXA2 expression was significantly decreased in the fetal lung tissue, and N-FOXA2 was significantly increased in control group (P<0.05), but there was no significant changes in the total FOXA2 (P>0.05). It was concluded that GDM can cause fetal lung development and maturation disorders, and FOXA2 in fetal lung tissue decreases while nitrocellulose FOXA2 increases.

Preparation and study of the antibacterial ability of graphene oxide-catechol hybrid polylactic acid nanofiber mats.

The functionalization of electrospun mats with antimicrobial nanomaterials is an attractive strategy when developing functional graphene oxide coating materials to prevent bacterial colonization on surfaces. In this study, we demonstrated a simple approach to produce antimicrobial electrospun mats by dip-coating a polylactic acid (PLA) nanofiber into a graphene oxide-catechol derivative. PLA was first electrospun to yield narrow-diameter polymeric nanofibers. We then modified the graphene oxide (GO) with a catechol derivative - dopamine methacrylamide monomer (DMA) - to synthesize a GO-DMA nanocomposite material which exhibited robust antimicrobial properties. The catechol groups promote the immobilization of graphene oxide onto the PLA nanofibers and possess strong antimicrobial properties. We therefore selected this functional group to modify GO. We dipped the GO-DMA onto the PLA nanofiber to produce the final functionalized electrospun mats. The PLA mats which were functionalized using the GO-DMA nanocomposite (PLA-GO-DMA) displayed antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. Furthermore, we studied the biocompatibility of the mats by culturing the cell lines (HepG2, A549, and HUVEC-C) of PLA-GO-DMA among the nanofibers which exhibited excellent biocompatibility. These results collectively demonstrate the potential of PLA-GO-DMA nanofiber mats as antimicrobial biomaterials and provide fundamental information toward the establishment of future biomedical applications.

Phillyrin produced by Colletotrichum gloeosporioides, an endophytic fungus isolated from Forsythia suspensa.

To investigate the phillyrin-producing endophytic fungi from the medicinal plant Forsythia suspensa, a total of 24 strains of endophytic fungi were isolated from the healthy stems, leaves and fruits of the plant, 9 from stems, 5 from leaves, and 10 from fruits respectively. All fungal isolates were fermented in liquid PDA medium and their extracts were preliminary analyzed by TLC. One isolated strain G10, which was from the fruit of F. suspensa, had the same R(f) value as authentic phillyrin. The potential phillyrin-producing fungus G10 was further analyzed by HPLC and HPLC-MS, and the results showed that the isolate G10 possessed of a retention time and ion peaks identical with the authentic compound phillyrin. The isolate G10 was identified as Colletotrichum gloeosporioides based on the morphological characteristics and ITS sequence analysis. The current research indicates that the numerous endophytic fungi inside the medicinal plants are precious resource for the pharmaceutical natural products that are originally from the plants.