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Furfural (FF) is an important bio‐based platform compound derived from lignocellulose. It can be converted into many industrially valuable chemicals, a typical one being methyl‐2‐furoate (MF). At present, MF production depends largely on vigorous one‐step chemical catalysis (oxidative esterification), in which expensive catalysts (precious metals) and a high temperature (60–120 °C) are required. To reduce the costs of this procedure, a mild, green, and cheap chemoenzymatic process is proposed where FF is initially chemically oxidized to furoic acid (FA), and then FA is enzymatically esterified to MF. Neither step requires an expensive catalyst, and both occur at low temperatures (30–50 °C). For the chemical oxidation process, the optimized FA yield of 83.7% was obtained at 40 °C with an FF/BTIC (1,3‐bis(2,4,6‐trimethylphenyl) imidazolium chloride) molar ratio of 0.18, 10 mL N‐methyl pyrrolidone, and 0.1 MPa oxygen pressure. For the enzymatic esterification, the optimized MF yield reached 80.6% at 50 °C with 50 mg•mL−1 enzyme loading and an alcohol/acid ratio of 7:1. Kinetic studies demonstrated the oxidation to be a sixth‐order reaction, and the esterification to be an endothermic reaction. For both oxidation and esterification reactions, the relationship between the rate constant and temperature agreed well with the Arrhenius equation. For esterification, the relationship between the equilibrium constant and the temperature also agreed with the Van't Hoff equation. A 67.5% MF yield was obtained when sequential oxidation and esterification were initiated from FF. The development of chemoenzymatic processes for MF production from FF is effective and has potential value in decreasing the production cost of MF. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

This study aims to investigate the anaerobic digestion (AD) performance of Broussonetia papyrifera, a wide distributed nitrogen-rich and lignocellulosic-like plant, for methane production. The fermentation was conducted with the volatile solid (VS) concentration at 0.5%, 1.0%,1.5%,2.0% and 4.0% under 37°C and 55°C for 30 days, respectively. Results suggested that the feedstock concentration at 2.0% and fermentation temperature at 55°C was optimal for the AD treatment of Broussonetia papyrifera. A maximal specific methane yield was achieved at 277.72 ± 15 mL/g VS, which was 94.71% higher than that for the maximum specific methane under the thermophile condition, likely because that the C/N was more suitable compared with other lignocellulosic biomass. A kinetic study suggested that the modified Gompertz equation was reliable (determination coefficients R2 greater than 0.97) to describe the kinetic behavior of anaerobic digestion of Broussonetia papyrifera. In general, Broussonetia papyrifera was proved to be a suitabe feedstock for anaerobic digestion for methane production. [ABSTRACT FROM AUTHOR]

Abstract Background DNA microarray technology provides a powerful tool for characterizing gene expression on a genome scale. While the technology has been widely used in discovery-based medical and basic biological research, its direct application in clinical practice and regulatory decision-making has been questioned. A few key issues, including the reproducibility, reliability, compatibility and standardization of microarray analysis and results, must be critically addressed before any routine usage of microarrays in clinical laboratory and regulated areas can occur. In this study we investigate some of these issues for the Applied Biosystems Human Genome Survey Microarrays. Results We analyzed the gene expression profiles of two samples: brain and universal human reference (UHR), a mixture of RNAs from 10 cancer cell lines, using the Applied Biosystems Human Genome Survey Microarrays. Five technical replicates in three different sites were performed on the same total RNA samples according to manufacturer's standard protocols. Five different methods, quantile, median, scale, VSN and cyclic loess were used to normalize AB microarray data within each site. 1,000 genes spanning a wide dynamic range in gene expression levels were selected for real-time PCR validation. Using the TaqMan® assays data set as the reference set, the performance of the five normalization methods was evaluated focusing on the following criteria: (1) Sensitivity and reproducibility in detection of expression; (2) Fold change correlation with real-time PCR data; (3) Sensitivity and specificity in detection of differential expression; (4) Reproducibility of differentially expressed gene lists. Conclusion Our results showed a high level of concordance between these normalization methods. This is true, regardless of whether signal, detection, variation, fold change measurements and reproducibility were interrogated. Furthermore, we used TaqMan® assays as a reference, to generate TPR and FDR plots for the various normalization methods across the assay range. Little impact is observed on the TP and FP rates in detection of differentially expressed genes. Additionally, little effect was observed by the various normalization methods on the statistical approaches analyzed which indicates a certain robustness of the analysis methods currently in use in the field, particularly when used in conjunction with the Applied Biosystems Gene Expression System.

Currently, there is no cure for spinal cord injury (SCI), a heavy burden on patients physiology and psychology. We found that microRNA-139-5p (miR-139-5p) expression was significantly downregulated in damaged spinal cords in mice. So, we aimed to test the effect of treatment with miR-139-5p on functional recovery and neuropathic pain in mice with SCI and investigate the underlying mechanism. The luciferase reporter assay revealed that miR-139-5p directly targeted mammalian sterile 20-like kinase 1 (Mst1), and miR-139-5p treatment suppressed Mst1 protein expression in damaged spinal cords of mice. Wild-type mice and Mst1(−/−) mice were exposed to SCI and treated with miR-139-5p agomir via intrathecal infusion. Treatment of SCI mice with miR-139-5p accelerated locomotor functional recovery, reduced hypersensitivities to mechanical and thermal stimulations, and promoted neuronal survival in damaged spinal cords. Treatment with miR-139-5p enhanced phosphorylation of adenosine monophosphate-activated protein kinase alpha (AMPKα), improved mitochondrial function, and suppressed NF-κB-related inflammation in damaged spinal cords. Deficiency of Mst1 had similar benefits in mice with SCI. Furthermore, miR-139-5p treatment did not provide further protection in Mst1(−/−) mice against SCI. In conclusion, miR-139-5p treatment enhanced functional recovery and reduced pain hypersensitivity in mice with SCI, possibly through targeting Mst1. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are approaching their theoretical limit and can no longer keep up with the increasing demands of human society. Lithium-sulfur batteries, with a high theoretical specific energy, are promising candidates for next generation energy storage. However, the use of Li metal in Li-S batteries compromises both safety and performance, enabling dendrite formation and causing fast capacity degradation. Previous studies have probed alternative battery systems to replace the metallic Li in Li-S system, such as a Si/Li2S couple, with limited success in performance. Recently, there is a focus on red P as a favorable anode material to host Li. Here, we establish a novel battery scheme by utilizing a P/C nanocomposite anode and pairing it with a Li2S coated carbon nanofiber cathode. We find that red P anode can be compatible in ether-based electrolyte systems and can be successfully coupled to a Li2S cathode. Our proof of concept full-cell displays remarkable specific capacity, rate and cycling performances. We expect our work will provide a useful alternative system and valuable insight in the quest for next generation energy storage devices. [ABSTRACT FROM AUTHOR]

High-capacity lithium-containing alloy anodes (e.g., Li4.4Si, Li4.4Sn, and Li3P) enable lithium-free cathodes (e.g., Sulfur, V2O5, and FeF3) to produce next-generation lithium-ion batteries (LIBs) with high energy density. Herein, we design a Li3P/C nanocomposite with Li3P ultrafine nanodomains embedded in micrometer-scale porous carbon particles. Benefiting from the unique micro/nanostructure of the Li3P/C nanocomposite, electrons transfer rapidly through the conductive pathway provided by the porous carbon framework and the volume change between Li3P and P is confined in the nanopores of the carbon, which avoids the collapse of the whole Li3P/C composite particles. As expected, the as-achieved Li3P/C nanocomposite provided a high available lithium-ion capacity of 791 mAh/g (calculated based on the mass of Li3P/C) at 0.1 C during the initial delithiation process. Meanwhile, the Li3P/C nanocomposite showed 75% of its 0.5 C capacity at 6 C and stable cycling stability. [ABSTRACT FROM AUTHOR]

BACKGROUND: The preparation of maleic acid from the oxidation of renewable furfural has attracted significant attention, but research regarding the direct transformation of biomass‐derived sugar to maleic acid is rare. The research regarding the direct transformation of xylose to maleic acid would further promote its industrial applications. RESULTS: The direct synthesis of maleic acid from xylose was investigated based on a sustainable system of deep eutectic solvents (DESs). Four DESs were screened to evaluate their abilities for the dehydration of xylose. Hydrogen peroxide (H2O2) was then loaded to realize the oxidation of furfural without the separation of intermediates. A good maleic acid yield of 20.8%, along with 5.0% of fumaric acid, based on the xylose content were obtained under the initial xylose loading of 50 mM, a tin(IV) chloride (SnCl4)–xylose molar ratio of 4:1, in a monophase choline chloride (ChCl)–formic acid (Fa) (molar ratio of 1:6) system at 120 °C for 2 h. Then, 4 mL of H2O2 per mmol furfural was loaded for a further 10 min at 120 °C. CONCLUSION: This ChCl–Fa–SnCl4–H2O2 system possesses a higher oxidation selectivity to maleic acid with no furanone and succinic acid. Moreover, it was interesting that ChCl and SnCl4 could be recovered through natural recrystallization. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

To achieve good rate capability of lithium metal anodes for high-energy-density batteries, one fundamental challenge is the slow lithium diffusion at the interface. Here we report an interpenetrated, three-dimensional lithium metal/lithium tin alloy nanocomposite foil realized by a simple calendering and folding process of lithium and tin foils, and spontaneous alloying reactions. The strong affinity between the metallic lithium and lithium tin alloy as mixed electronic and ionic conducting networks, and their abundant interfaces enable ultrafast charger diffusion across the entire electrode. We demonstrate that a lithium/lithium tin alloy foil electrode sustains stable lithium stripping/plating under 30 mA cm−2 and 5 mAh cm−2 with a very low overpotential of 20 mV for 200 cycles in a commercial carbonate electrolyte. Cycled under 6 C (6.6 mA cm−2), a 1.0 mAh cm−2 LiNi0.6Co0.2Mn0.2O2 electrode maintains a substantial 74% of its capacity by pairing with such anode. Sluggish lithium diffusion on the surface of Li metal anodes poses a fundamental challenge. Here the authors report a Li/Li22Sn5 alloy design to address this issue. The composite anode sustains stable Li stripping/plating cycling with a low overpotential of 20 mV under 30 mA cm−2 in a commercial carbonate electrolyte. [ABSTRACT FROM AUTHOR]

Transferable DNA markers are essential for breeding and genetics. Grapevine (Vitis) breeders utilize disease resistance alleles from congeneric species ~20 million years divergent, but existing Vitis marker platforms have cross-species transfer rates as low as 2%. Here, we apply a marker strategy targeting the inferred Vitis core genome. Incorporating seven linked-read de novo assemblies and three existing assemblies, the Vitis collinear core genome is estimated to converge at 39.8 Mb (8.67% of the genome). Adding shotgun genome sequences from 40 accessions enables identification of conserved core PCR primer binding sites flanking polymorphic haplotypes with high information content. From these target regions, we develop 2,000 rhAmpSeq markers as a PCR multiplex and validate the panel in four biparental populations spanning the diversity of the Vitis genus, showing transferability increases to 91.9%. This marker development strategy should be widely applicable for genetic studies in many taxa, particularly those ~20 million years divergent. Trait introgression requires universal markers, but cross-species transferability of current SNP markers can be as low as 2%. Here, the authors use an AmpSeq haplotype strategy targeting the collinear core genome for marker development and show transferability increases to 91.4% in the Vitis genus. [ABSTRACT FROM AUTHOR]

Background Apoptosis plays an important role in various diseases, including spinal cord injury (SCI). Hyperbaric oxygen (HBO) and erythropoietin (EPO) promote the recovery from SCI, but the relationship between apoptosis and the combination therapeutic effect is not completely clear. Objective The purpose of this study was to investigate the effects of HBO and EPO on SCI and the mechanisms that underlie their therapeutic benefits. Design The study was designed to explore the effects of HBO and EPO on SCI through a randomized controlled trial. Methods Sixty young developing female Sprague-Dawley rats were randomly divided into groups of 12 rats receiving sham, SCI, HBO, EPO, or HBO plus EPO. The SCI model was modified with the Allen method to better control consistency. HBO was performed for 1 hour per day for a total of 21 days, and EPO was given once per week for a total of 3 weeks. Both methods were performed 2 hours after SCI. Locomotor function was evaluated with the 21-point Basso-Beattie-Bresnahan Locomotor Rating Scale, an inclined-plane test, and a footprint analysis. All genes were detected by Western blotting and immunohistochemistry. The level of cell apoptosis was determined by Hoechst staining. Results The results showed that HBO and EPO promoted the recovery of locomotor function in the hind limbs of rats by inhibiting the apoptosis of neurons. During this period, the expression of B-cell lymphoma/leukemia 2 protein (Bcl-2) increased significantly, whereas the expression of Bcl-2–associated X protein (Bax) and cleaved caspase 3 decreased significantly, indicating the inhibition of apoptosis. Meanwhile, the expression of G protein–coupled receptor 17 decreased, and that of myelin basic protein increased, suggesting that there may be a potential connection between demyelination and neuronal apoptosis. Limitations The limitations of the study include deviations in the preparation of SCI models; lack of reverse validation of molecular mechanisms; absence of in vitro cell experiments; and only one time point after SCI was studied. Conclusions HBO and EPO treatments are beneficial for SCI, especially when the 2 therapies are combined. [ABSTRACT FROM AUTHOR]