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Zinc-based aqueous rechargeable batteries have attracted extensive attention due to their low cost, safety, and environmental friendliness. However, dendrite growth and hydrogen evolution of Zn anodes limit their large-scale application. A new strategy to produce a polyacrylamide/reduced graphene oxide (PAM@rGO) molecular nanobrush coating and control Zn electrolyte interface engineering is proposed for use in highly reversible Zn plating/stripping. Hydrogen evolution is inhibited, and Zn deposition is consolidated using the rich zincophilic functional groups of the branched polyacrylamide chain and the high conductivity of rGO. Due to the synergistic effects of corrosion resistance and dendrite-free growth, PAM@rGO/Zn provides prolonged and reversible Zn plating/stripping. Density functional theory (DFT) calculations expand on homogenized nucleation. The PAM@rGO/Zn‖activated carbon (AC) capacitor exhibits long cyclic stability, fast ion transfer, and minimal interfacial impedance. This study provides experimental and theoretical bases for the structural design of Zn anode. [ABSTRACT FROM AUTHOR]

The rapid evolution of resistance in agricultural pest poses a serious threat to global food security. However, the mechanisms of resistance through metabolic regulation are largely unknown. Here, we found that a GST gene cluster was strongly selected in North China (NTC) population, and it was significantly genetically-linked to lambda-cyhalothrin resistance. Knockout of the GST cluster using CRISPR/Cas9 significantly increased the sensitivity of the knockout strain to lambda-cyhalothrin. Haplotype analysis revealed no non-synonymous mutations or structural variations in the GST cluster, whereas GST_119 and GST_121 were significantly overexpressed in the NTC population. Silencing of GST_119 or co-silencing of GST_119 and GST_121 with RNAi significantly increased larval sensitivity to lambda-cyhalothrin. We also identified additional GATAe transcription factor binding sites in the promoter of NTC_GST_119. Transient expression of GATAe in Hi5 cells activated NTC_GST_119 and Xinjiang (XJ)_GST_119 transcription, but the transcriptional activity of NTC_GST_119 was significantly higher than that of XJ_GST_119. These results demonstrate that variations in the regulatory region result in complex expression changes in the GST cluster, which enhances lambda-cyhalothrin resistance in field-populations. This study deepens our knowledge of the evolutionary mechanism of pest adaptation under environmental stress and provides potential targets for monitoring pest resistance and integrated management. A glutathione S-transferase gene cluster in the cotton bollworm, Helicoverpa armigera, contributes to natural insecticide resistance in this agricultural pest. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable zinc-ion hybrid supercapacitors are considered to be a promising candidate for large-scale energy storage devices owing to their high safety, long life, and low price. In this paper, a nitrogen doped hierarchical porous carbon is evaluated as the cathode for aqueous rechargeable zinc-ion hybrid supercapacitors. Benefiting from the synergistic merits of excellent structural features of N-HPC and tiny zinc dendrite of Zn anode in ZnSO4 electrolyte, the zinc-ion hybrid supercapacitor exhibits excellent energy storage performance including high capacity of 136.8 mAh·g−1 at 0.1·Ag−1, high energy density of 191 Wh·kg−1, large power density of 3,633.4 W·kg−1, and satisfactory cycling stability of up to 5,000 cycles with a capacity retention of 90.9%. This work presents a new prospect of developing high-performance aqueous rechargeable zinc ion energy storage devices. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)-modified copper foil composite material was prepared by electrocoagulation of graphene oxide (GO) and a subsequent chemical reduction process. The effects of deposition voltages and the reduction time on the morphology, structure and electrochemical performances of the sample are investigated. The uniform surface morphology of GO/Cu sample obtained at a deposition voltage of 2.5 V. However, the appropriate chemical reduction not only improves the electrical conductivity of GO/Cu, but also enhances anticorrosion performance. At the optimized deposition voltages (2.5 V) and reduction time (20 min), the rGO/Cu shows the highest anticorrosive property and good conductivity. The protective efficiency of rGO/Cu is up to 98% (vs bare copper) as compared with 60% of GO/Cu according to Tafel analyses. The conductivity of rGO/Cu is close to bare copper according to the electrochemical impedance spectroscopy (EIS) results of Ni(OH)2/rGO/Cu and measurement of surface resistivity. We consider that rGO/Cu is a suitable material for realizing the copper foil manufacture with high corrosion resistance without sacrificing conductivity. [ABSTRACT FROM AUTHOR]

Herein, we report the identification of putative promoters for the non-structural proteins (NS) and capsid structural proteins (VP) of Helicoverpa armigera densovirus (HaDV2) as well as a potential mechanism for how these promoters might be regulated. For the first time, we report that VP is able to transactivate the VP promoter and, to a lesser degree, the NS promoter in densoviruses. In addition to this, another promoter-like sequence designated P2, when co-transfected with the VP gene, enhanced luciferase activity by approximately 35 times compared to a control. This suggests that there are two promoters for VP in HaDV2 and that the VP of parvoviruses might play a more important role in viral transcription than previously appreciated. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis (Bt) toxin receptors play important roles in the killing of pests, and investigation on characterization of the receptors is essential for utilization of Bt and management of insect resistance. Here, recombinant and mosaic receptors of Bt Cry1Ac toxin from Helicoverpa armigera were expressed in Spodoptera litura Sl-HP cells and their influences on cytotoxicity of activated Cry1Ac toxin were investigated. When H. armigera aminopeptidase N1 (APN1), alkaline phosphatase 2 (ALP2) and cadherin fused with or without GFP tag were, respectively, expressed in Sl-HP cells, live cell-immunofluorescence staining detection revealed that the quantity of the toxin binding to cadherin or cadherin-GFP was much more than that binding to ALP2 and APN1 or their fusion proteins with GFP, and only the cadherin- or cadherin-GFP-expressing cells showed aberrant cell morphology after the treatment of the toxin at low concentrations. ALP2 and APN1 fused with or without GFP tag did not significantly enhance the cadherin-mediated cytotoxicity of the toxin. The mosaic ALP-TBR-GFP-GPI was located on cell membrane, but did not bind to the toxin. The mosaic truncated cadherin-GFP-GPI was not located on cell membrane even if the signal peptide was sustained. The concentrations of the toxin resulting in swelling of 50 % cells for noncadherin-expressing Sl-HP cells and cadherin-expressing Hi5 cells were 5.08 and 9.50 µg/ml within 1 h, respectively. Taken together, our data have indicated that the binding affinity of ALP2 and APN1 to activated Cry1Ac toxin is much weaker than that of cadherin and both ALP2 and APN1 do not enhance the cytotoxicity of the toxin even though cadherin is co-expressed, and the mosaic receptor of ALP2 inserted with cadherin toxin binding domain does not mediate cytotoxicity of the toxin. In addition, the noncadherin-expressing Sl-HP cells are more susceptible to activated Cry1Ac than the cadherin-expressing Hi5 cells. [ABSTRACT FROM AUTHOR]

In the paper, we report synthesis of LiNiCoMnO nanocrystals by a facile resorcinol formaldehyde gel route. The initial polymerization of precursor solution and subsequent high-temperature calcination results in the formation of LiNiCoMnO nanocrystals. The XRD, SEM, and electrochemical tests show the influence of calcination temperatures on the structures and electrochemical performances of obtained products. The XRD results reveal that the elevated temperature helps to improve the layered structure of the LiNiCoMnO nanocrystals, and the SEM results demonstrated that the elevated temperature helps to enlargement particle size. For lithium ion battery cathodes, the electrochemical performances can be well determined by corresponding structures. Among them, the 850 °C sample shows an initial discharge capacity of 259.9 mAh g with Coulombic efficiency of 80.1 % at a current density of 40 mA g. After 50 cycles, the sample also can retain a capacity of 204.8 mAh g at 200 mA g, which is 87.6 % of initial value. Even at a higher rate of 1000 mA g, the sample shows a stable discharge capacity of 130 mAh g. Maybe, the resorcinol formaldehyde gel route is suitable to prepare lithium ion battery cathode LiNiCoMnO. Graphical Abstract: The lithium rich layered oxides LiNiCoMn4O have been prepared by a facile resorcinol formaldehyde gel route. The optimal sample with the size of 200-300 nm shows high discharge capacity, good cycling stability and rate capability as lithium ion battery cathode.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Dysregulation of ribosome biogenesis causes human diseases, such as Diamond-Blackfan anemia, del (5q-) syndrome and bone marrow failure. However, the mechanisms of blood disorders in these diseases remain elusive. Through genetic mapping, molecular cloning and mechanism characterization of the zebrafish mutant cas002, we reveal a novel connection between ribosomal dysfunction and excessive autophagy in the regulation of hematopoietic stem/progenitor cells (HSPCs). cas002 carries a recessive lethal mutation in kri1l gene that encodes an essential component of rRNA small subunit processome. We show that Kri1l is required for normal ribosome biogenesis, expansion of definitive HSPCs and subsequent lineage differentiation. Through live imaging and biochemical studies, we find that loss of Kri1l causes the accumulation of misfolded proteins and excessive PERK activation-dependent autophagy in HSPCs. Blocking autophagy but not inhibiting apoptosis by Bcl2 overexpression can fully rescue hematopoietic defects, but not the lethality of kri1lcas002 embryos. Treatment with autophagy inhibitors (3-MA and Baf A1) or PERK inhibitor (GSK2656157), or knockdown of beclin1 or perk can markedly restore HSPC proliferation and definitive hematopoietic cell differentiation. These results may provide leads for effective therapeutics that benefit patients with anemia or bone marrow failure caused by ribosome disorders. [ABSTRACT FROM AUTHOR]

The midgut of lepidopteran larvae serves as a target for many pathogens such as Bacillus thuringiensis (Bt). Cell lines originating from midgut tissues will be very helpful tools in many research fields. However, to date, no Bt-susceptible midgut-derived cell lines are available. Here, we reported that a novel cell line, designated as HNU-Ha-MG1, was established from midgut tissue of the fourth instar larvae of Helicoverpa armigera. This cell line grew well in Grace's insect cell culture medium supplemented with 10−15% fetal bovine serum. The shape of the most cells was round or polygonal, and some tended to aggregate to form multiple cell masses. The size of the cells was 13.8 ± 1.8 μm in diameter, and the maximum density reached (2.40 ± 0.15) × 10 cells/ml. The population doubling time during logarithmic growth phase was 58.6 ± 7.0 h at 28°C. The number of chromosomes was about 90-130, which exhibited typical chromosome characteristics of lepidopteran cell lines. The patterns of random amplified polymorphic DNA of the cell line were different from those of Sl-HP and Hi5 cell lines which were frequently used in our laboratory. 20-Hydroxyecdysterone induced apoptosis in a very small part of cells at 2 μg/ml but did not affect expression of autophagy-related protein 8 (Atg8) and its lipidation at 36 h post-treatment. The cell line was permissive to Autographa californica nuclear polyhedrosis virus (AcMNPV) and H. armigera nuclear polyhedrosis virus (HaSNPV). This cell line was found to be susceptible to activated Cry1C at the final concentration of 0.5−1.0 μg/ml but not to the activated Cry1Ac. [ABSTRACT FROM AUTHOR]

Graphene nanosheet and ternary-component nickel cobalt aluminum-layered double hydroxide composite (GNS/NiCoAl-LDH) has been successfully fabricated by a facile assembly method. The NiCoAl-LDH flakes homogeneously distribute on the surfaces of GNS, forming a three-dimensional nanosheets array structure. Electrochemical properties are characterized by cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy. The influence of GNS doped content on the electrochemical behavior of GNS/NiCoAl-LDH composite has been studied. The result indicate that when the GNS content is 3.0 %, the GNS/NiCoAl-LDH composite electrode exhibits a maximum specific capacitance of 1,962 F g at 1 A g and remains at 1,180 F g even at a high current density of 10 A g. After 2,000 cycles, the composite electrode keeps a remarkable specific capacitance of 1,260 F g at 5 A g. The enhanced electrochemical performances of the composite are attributed to the highly electron conductivity and large specific surface area of the graphene nanosheets. This newly designed GNS/NiCoAl-LDH composite may offer a promising electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate approximation operators with logarithmic sigmoidal function of a class of two neural networks weights and a class of quasi-interpolation operators. Using these operators as approximation tools, the upper bounds of estimate errors are estimated for approximating continuous functions. [ABSTRACT FROM AUTHOR]

Development of insect resistance to Bacillus thuringiensis (Bt) toxins threatens the sustained successful application of Bt-based biological control tactics. Multi-mechanisms of resistance have been proposed, such as alteration of toxin-binding proteins, changes of proteases in midgut and so on. The other responses of the Cry1Ac-selected insects might also contribute to the evolution of resistance. Here, the Cry1Ac-selected Trichoplusia ni TnH5 cells with high resistance were subjected to analysis of proteome and the differentially expressed proteins were identified using mass spectrometry. The differential proteins included transporter, molecular chaperon, structural molecules and many other molecules involved in protein metabolism, signal transduction, nucleotide binding, lipid biosynthesis, carbohydrates metabolism and energy production, suggesting that a complex mechanisms involved in the development of insect resistance to Bt Cry1Ac toxins at cellular levels. The decrease of protein synthesis, changes of signal transduction, more rapid energy production, the enhanced lipid synthesis and the decline of possible Cry1Ac-binding proteins in cytoplasm and other events might contribute to the development of resistance in the selected cells. Our results provide some new cues for understanding the mechanism of Bt resistance. [ABSTRACT FROM AUTHOR]

We induced 3 cell lines that were in vitro cultured from Lepidoptera with heat inactivated Escherichia coli DH5α to stimulate the antibacterial peptide followed by antibacterial activity assay, induction dynamic research and Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine SDS-PAGE) experiment. The antibacterial activity of the induced BTI-Tn-5B1 cell line was the highest, and the antibacterial activity increased gradually to the highest level in 16 hours after stimulation. A new antibacterial peptide with a molecular weight of about 8000 Da was preferentially induced in Trichoplusia ni BTI-Tn-5B1 cells in 16 hours after stimulation. Antibacterial activity assays indicated that it had inhibition against Staphylococcus aureus, Escherichia coli K12D31 and Salmonella derby. It has especially strong inhibition against Gram-negative bacteria such as Escherichia coli K12D31 and Salmonella derby. [ABSTRACT FROM AUTHOR]

Selection for resistance against Bacillus thuringiensis (Bt) Cry1Ac10 in the Trichoplusia ni (Hübner) cell line BTI-TN-5B1-4 (TnH5) was tested, and the development of resistance in the selected cells was like a S-form curve. Monitoring at the Cry1Ac10 50th challenge, the resistance ratio was 1, 294-fold as many as that of initial cells. But the resistance to Cry1Ac10 declined gradually when the selection was relaxed. The resistance declined rapidly at the low level of resistance and slowly at the high level of resistance. This resistant cell had high resistance to all the tested solubilized trypsin-treated mixture of crystal multitoxins of B. thuringiensis subsp. aizawai GC-91, an engineering bacterium of Bt, B. thuringiensis subsp. aizawai HD-133 and B. thuringiensis subsp. kurstaki HD-1, and low cross-resistance (19.7-fold) to activated Cry1C. Both N-acetyl- d-galactosamine (GalNAc) and tunicamycin did not inhibit the toxicity of Cry1Ac10 to the susceptible TnH5 cells. Comparison of the total proteins of the selected resistant cells with that of the nonselected susceptible cells by two-dimensional electrophoresis analysis showed that were obvious differences among the 11 protein expression. These results strongly suggest that there exists an unknown mechanism of resistance in the cell line that was different from the reported mechanisms in insects. [ABSTRACT FROM AUTHOR]

Evolution of resistance by pests reduces the benefits of transgenic crops that produce insecticidal proteins from Bacillus thuringiensis (Bt). Here we analyzed resistance to Bt toxin Cry1Ac in a field-derived strain of pink bollworm (Pectinophora gossypiella), a global pest of cotton. We discovered that the r14 allele of the pink bollworm cadherin gene (PgCad1) has a 234-bp insertion in exon 12 encoding a mutant PgCad1 protein that lacks 36 amino acids in cadherin repeat 5 (CR5). A strain homozygous for this allele had 237-fold resistance to Cry1Ac, 1.8-fold cross-resistance to Cry2Ab, and developed from neonate to adult on Bt cotton producing Cry1Ac. Inheritance of resistance to Cry1Ac was recessive and tightly linked with r14. PgCad1 transcript abundance in midgut tissues did not differ between resistant and susceptible larvae. Toxicity of Cry1Ac to transformed insect cells was lower for cells expressing r14 than for cells expressing wild-type PgCad1. Wild-type PgCad1 was transported to the cell membrane, whereas PgCad1 produced by r14 was not. In larval midgut tissue, PgCad1 protein occurred primarily on the brush border membrane only in susceptible larvae. The results imply r14 mediates pink bollworm resistance to Cry1Ac by reduced translation, increased degradation, and/or mislocalization of cadherin. [ABSTRACT FROM AUTHOR]

Human parvovirus B19 (B19) is a small nonenveloped icosahedral virus with a single-stranded, linear 5.6 kb DNA genome. The p6 promoter, at map unit 6 of the viral genome, controls the expression of all B19 transcripts. Some previous reports revealed that this promoter is transactivated by NS1 protein. In an attempt to investigate the roles of other small viral proteins in the control of the p6 promoter activity, various truncated promoter/reporter constructs along with these nonstructural protein expression vectors were introduced into Hela cells. The results showed that the putative X protein upregulated the activity of p6 promoter significantly, but that the 11 kDa protein did not. Furthermore, the possible responsive DNA elements for X protein were identified to be located primarily between nt 265 and 343 of the p6 promoter region. In addition, we observed that deletion of the potential ATF/CREB binding sites located in 5′ terminal nucleotide influenced the activity of p6 promoter significantly. [ABSTRACT FROM AUTHOR]