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Electrocatalysts for hydrogen evolution made from earth’s rich elements are key to a sustainable and clean hydrogen economy. Now, using a straightforward way to make valid catalysts with preferable catalytic activity from inexpensive raw materials in large scale remains challenge. The preparation of nickel-sulfur hybrid nanoplate electrocatalyst has a deep consideration because of its ordinary preparation process, outstanding property, and fine stabilization. In this work, employing an improved chemical vapor deposition (CVD) synthesis method to fabricate a highly efficient and stable NiS2/NiS electrocatalyst prepared by changing the mass of nickel-sulfur ratios of 8:1 (NiS2/NiS-8), 4:1 (NiS2/NiS-4), 2:1 (NiS2/NiS-2), and 1:1 (NiS2/NiS-1), applied to hydrogen evolution reactions (HER). The acquired NiS2/NiS-4 showed excellent HER performance with an overpotential of 202 mV to drive 100 mA/cm2 in 1 M KOH solution with a Tafel slope of 69.0 mV/dec, also with 30 h stability testing. This vigorous catalyst, fabricated from commercial Ni foam, has a potential for industrialization of hydrogen economy and will stimulate the industrial development of nonprecious metal catalyst.

Background Extensive muscle atrophy is a common occurrence in orthopaedics patients who are bedridden or immobilized. The incidence is higher in intensive care unit (ICU) inpatients. There is still controversy about how to use neuromuscular electrical stimulation (NMES) in ICU patients. We aim to compare the effectiveness and safety of NMES to prevent muscle atrophy in intensive care unit (ICU) patients without nerve injury. Methods ICU patients without central and peripheral nerve injury were randomized into experimental group I (Exp I: active and passive activity training (APAT) + NMES treatment on the gastrocnemius and tibialis anterior muscle), experimental group II (Exp II: APAT + NMES treatment on gastrocnemius alone), and control group (Ctl: APAT alone). Changes in the strength of gastrocnemius, the ankle range of motion, and the muscle cross-section area of the lower leg were evaluated before and after the intervention. Also, changes in prothrombin time, lactic acid, and C-reactive protein were monitored during the treatment. Results The gastrocnemius muscle strength, ankle joint range of motion, and cross-sectional muscle area of the lower leg in the three groups showed a downward trend, indicating that the overall trend of muscle atrophy in ICU patients was irreversible. The decrease in gastrocnemius muscle strength in Exp I and Exp II was smaller than that in the control group (P P P P > 0.05). Conclusion In addition to early exercise training, NMES should be applied to prevent muscle atrophy for patients without nerve injury in ICU. Also, simultaneous NMES treatment on agonist/antagonist muscle can enhance the effect of preventing muscle atrophy. Trial registration This study was prospectively registered in China Clinical Trial Registry (www.chictr.org.cn) on 16/05/2020 as ChiCTR2000032950.

Ammonium vanadate (NH4V3O8) materials have attracted considerable attention due to their low cost, high discharge capacity, and simple synthesis process. However, the further application of NH4V3O8 materials as cathode for lithium-ion batteries is hindered by the low electronic conductivity and lithium-ion diffusion coefficient. Herein, intersperse Super P nanoparticles between NH4V3O8 microsheets to increase the Li+ diffusion coefficient of NH4V3O8 electrodes. Compared with pure NH4V3O8, the cycling stability of NH4V3O8/Super P composites improved obviously. At a current density of 15 mA g−1 after 200 cycles, the reversible capacity of composites (110 mAh g−1) is much higher than the pure NH4V3O8 (70 mAh g−1). Besides, the composites exhibit excellent rate capability, and the reversible capacity achieves 66 mAh g−1 at a high current density of 300 mA g−1. The excellent electrochemical performance is mainly attributed to the addition of Super P carbon black nanoparticles, which increases the conductivity and the Li+ diffusion coefficient.

Background Efficient and convenient genome-editing toolkits can expedite genomic research and strain improvement for desirable phenotypes. Zymomonas mobilis is a highly efficient ethanol-producing bacterium with a small genome size and desirable industrial characteristics, which makes it a promising chassis for biorefinery and synthetic biology studies. While classical techniques for genetic manipulation are available for Z. mobilis, efficient genetic engineering toolkits enabling rapidly systematic and high-throughput genome editing in Z. mobilis are still lacking. Results Using Cas12a (Cpf1) from Francisella novicida, a recombinant strain with inducible cas12a expression for genome editing was constructed in Z. mobilis ZM4, which can be used to mediate RNA-guided DNA cleavage at targeted genomic loci. gRNAs were then designed targeting the replicons of native plasmids of ZM4 with about 100% curing efficiency for three native plasmids. In addition, CRISPR–Cas12a recombineering was used to promote gene deletion and insertion in one step efficiently and precisely with efficiency up to 90%. Combined with single-stranded DNA (ssDNA), CRISPR–Cas12a system was also applied to introduce minor nucleotide modification precisely into the genome with high fidelity. Furthermore, the CRISPR–Cas12a system was employed to introduce a heterologous lactate dehydrogenase into Z. mobilis with a recombinant lactate-producing strain constructed. Conclusions This study applied CRISPR–Cas12a in Z. mobilis and established a genome editing tool for efficient and convenient genome engineering in Z. mobilis including plasmid curing, gene deletion and insertion, as well as nucleotide substitution, which can also be employed for metabolic engineering to help divert the carbon flux from ethanol production to other products such as lactate demonstrated in this work. The CRISPR–Cas12a system established in this study thus provides a versatile and powerful genome-editing tool in Z. mobilis for functional genomic research, strain improvement, as well as synthetic microbial chassis development for economic biochemical production.

An isolable and ambient stable bay-substituted perylene diimide adical anion salt was straightforwardly synthesized by base catalysis reduction of N,N-diethylhexyl-1,7-di(pentafluoro-phenoxyl) perylene diimide (DFPDI) in polar solvents, such as acetone, DMF, DMSO, NMP in yields of 48.7 %. Elemental analysis and 1H NMR, 13C NMR and EPR were carried out to confirm the formation of the compounds. Solvent-dependent cyclic voltammetries revealed the only condition for generating DFPDI radical anion in polar solvents—the reduction potential (DFPDI/DFPDI−) is more positive than −0.36 V (vs. Ag/AgCl). Redox studies revealed that DFPDI radical anion was not only ambient stable to moderate oxidants air (O2) and moisture for prolonged existence but also sensitive to strong oxidants-acid H+ and strong oxidization metal ions with low limit value.

Ht-2 is a novel oxaliplatin derivative previously identified in a compound screen performed by our laboratory. In the present study, we evaluated the antitumor effects of Ht-2 and investigated its underlying mechanism of action. Ht-2 exhibited anti-tumor activity and demonstrated low cytotoxicity in normal cells in vitro. The IC50 of Ht-2 was 2-10-fold lower than oxaliplatin in all of the cancer cell lines tested except MCF-7 cells, whereas, the value was threefold higher than cisplatin or oxaliplatin in normal HUVEC cells. Further studies indicated that Ht-2 caused S-phase arrest and led to apoptosis in HCT-116 cells through the activation of the caspase cascade. Moreover, Ht-2 treatment contributed to increased mitochondrial permeability by altering the Bax/Bcl-2 ratio and consequently induced mitochondrial dysfunction, mitochondrial membrane potential depletion, reactive oxygen species (ROS) elevation and cytochrome C release in HCT-116 cells. The cellular antioxidative superoxide dismutase 1 protein was also downregulated. We demonstrated that the cytotoxicity was almost completely recovered by antioxidant treatment, indicating a crucial role of ROS for Ht-2-induced apoptosis. Collectively, our data suggest that Ht-2 can target tumor cells by inducing mitochondrion-dependent apoptosis.

Na-A zeolite was successfully synthesized via the alkaline fusion method with oil shale ash as the raw material. The adsorption capacity of it was tested by removing Cu2+, Ni2+, Pb2+ and Cd2+ from aqueous solutions. The results reveal the maximum adsorption capacity of adsorbent for Pb2+, Cu2+, Cd2+ and Ni2+ were 224.72, 156.74, 118.34 and 53.02 mg/g, respectively. The effects of contact time and pH value of solutions on the adsorption efficiency of the zeolite were evaluated. Besides, The equilibrium adsorption data and the batch kinetic data were correlated with Langmuir and Freundlich models and the pseudo-first-order and pseudo-second-order models separately. The results show that the Langmuir isotherm and the pseudo-second-order equation were more suitable for the adsorption of Na-A zeolite for the metal ions. In addition, Thermodynamic parameters of the adsorption(the Gibbs free energy, entropy, and enthalpy) were also evaluated and discussed. The results demonstrate that the adsorption process was spontaneous and endothermic under natural conditions and the synthesized zeolite was an effective adsorbent for the removal of metal ions from aqueous solution.