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Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae) is one of the most important insect pests of rice, and it has been able to develop strong resistance to many insecticides. Triflumezopyrim, a new type of mesoionic insecticide developed by Corteva Agriscience, showed high biological activity in controlling piercing-sucking insect pests such as planthopper and leafhopper.In this study, we continuously selected a susceptible laboratory stain (Unsel) of L. striatellus for 16 generations by exposing it to triflumezopyrim in the laboratory. A 45.1-fold triflumezopyrim-resistant strain (Tri-sel) was established, in which cross-resistance to nitenpyram and acetamiprid was not detected. The realized heritability (hL. striatellus has a certain risk of resistance to triflumezopyrim after continuous selection. Triflumezopyrim resistance did not result in cross-resistance to neonicotinoid insecticides. The up-regulation of multiple P450 genes may mediate triflumezopyrim resistance in L. striatellus. © 2022 Society of Chemical Industry.

Hepatocellular carcinoma (HCC) is an aggressive malignancy with limited effective treatments and ranks as the second most lethal tumor. Immunotherapy has brought great hope for HCC treatment. Oxysophocarpine is a bioactive alkaloid which poses various pharmacological functions including neuroprotective, anti‐virus, anti‐convulsant, and anti‐nociception. However, there is little systematic study of Oxysophocarpine against HCC and its underlying potential and mechanism combined with immunotherapy in HCC treatment remain poorly unknown. This study was aimed to investigate whether Oxysophocarpine can distinctly suppress HCC cells and sensitize the immunotherapy of CD8+ T cells against HCC. We used HepG2, Hepa1‐6, and primary CD8+ T cells to perform in vitro assays and Hepa1‐6 subcutaneous tumor to conduct in vivo assay. Oxysophocarpine inhibited the proliferation and increased the apoptosis of HepG2 and Hepa1‐6 cells, meanwhile suppressed the migration of HepG2 and Hepa1‐6 cells. Oxysophocarpine sensitized the Lag‐3 immunotherapy effect of CD8+ T cells against HCC in vivo and in vitro by decreasing Fibrinogen‐like protein 1 (FGL1) expression through downregulating IL‐6‐mediated JAK2/STAT3 signaling, whereas Oxysophocarpine treatment had a little effect of CD8+ T cells cytotoxicity function against HCC with PD‐1, Tim‐3, or TIGIT blockade. Our studies provided preclinical basis for clinical application of Oxysophocarpine., Oxysophocarpine inhibited the proliferation, migration, and increased the apoptosis of HCC cells. Oxysophocarpine sensitized the Lag‐3 immunotherapy effect of CD8+ T against HCC by decreasing FGL1 expression through IL‐6‐mediated JAK2/STAT3 pathway.

Changes in global temperature and humidity as a result of climate change are producing rapid evolutionary changes in many animal species, including agricultural pests and disease vectors, leading to changes in allele frequencies of genes involved in thermotolerance and desiccation resistance. As some of these genes have pleiotropic effects on insecticide resistance, climate change is likely to affect insecticide resistance in the field. In this review, we discuss how the interactions between adaptation to climate change and resistance to insecticides can affect insecticide resistance in the field using examples in phytophagous and hematophagous pest insects, focusing on the effects of increased temperature and increased aridity. We then use detailed genetic and mechanistic studies in the model insect, Drosophila melanogaster, to explain the mechanisms underlying this phenomenon. We suggest that tradeoffs or facilitation between adaptation to climate change and resistance to insecticides can alter insecticide resistance allele frequencies in the field. The dynamics of these interactions will need to be considered when managing agricultural pests and disease vectors in a changing climate. © 2019 Society of Chemical Industry.

Li-O2 batteries (LOBs) with an extremely high theoretical energy density have been reported to be the most promising candidates for future electric storage systems. Porous catalysts can be beneficial for LOBs. Herein, 3D-ordered macroporous La0.6Sr0.4Co0.2Fe0.8O3 perovskite oxides (3D-LSCF) are applied as cathode catalysts in LOBs. With a high Brunauer-Emmett-Teller surface area (21.8 m2 g-1) and unique honeycomb-like macroporous structure, the 3D-LSCF catalysts possess a much higher efficiency than La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) nanoparticles. The unique 3D-ordered macropores play a significant role in the product deposition as well as oxygen and electrolyte transmission, which are crucial for the discharge-charge processes of LOBs.

Circular RNAs (circRNAs) have been identified in diverse cancers for their role in regulating multiple cellular processes by antagonizing microRNAs (miRNAs or miRs). However, the role of circRNA hsa_circ_0000092 in hepatocellular carcinoma (HCC) still remains enigmatic. Therefore, we aimed to investigate the specific mechanism of hsa_circ_0000092 in HCC. Differentially expressed circRNAs associated to HCC were initially analysed. The expression of hsa_circ_0000092, miR-338-3p and HN1 in HCC tissues and cell lines was examined. Next, the interaction among hsa_circ_0000092, miR-338-3p and HN1 was determined by dual-luciferase reporter, RNA pull-down and northern blot assays. Subsequently, a series of mimic, inhibitor or siRNA plasmids were delivered into HCC cells to validate the effects of hsa_circ_0000092, miR-338-3p and HN1 in controlling cell proliferation, migration, invasion and angiogenesis in vitro. Furthermore, the role of hsa_circ_0000092 in tumour growth of HCC in vivo was assessed with hsa_circ_0000092 depleted with siRNA. The hsa_circ_0000092/miR-338-3p/HN1 axis was predicted to participate in the development of HCC. hsa_circ_0000092 and HN1 were highly expressed while miR-338-3p was poorly expressed in HCC tissues and cell lines. hsa_circ_0000092 could competitively bind to miR-338-3p to up-regulate HN1 expression. Moreover, depleted hsa_circ_0000092 or elevated miR-338-3p was shown to suppress HCC cell proliferation, migration, invasion and angiogenesis in vitro via down-regulation of HN1. Furthermore, silencing hsa_circ_0000092 was demonstrated to suppress tumour growth in HCC in vivo. The results of this study suggested that hsa_circ_0000092 impaired miR-338-3p-mediated HN1 inhibition to aggravate the development of HCC, indicating that hsa_circ_0000092 is a potential candidate marker and therapeutic target for HCC.

Long noncoding RNA (lncRNA) differentiation antagonizing nonprotein coding RNA (DANCR) has been identified as an oncogene in several cancers. However, the biological function and role of DANCR in hepatocellular carcinoma (HCC) remain unclear. Our current study aimed to investigate the detailed mechanism of DANCR in HCC. We found that DANCR was significantly upregulated in HCC cell lines in comparison to LO2 cells. Then, we observed that knockdown of DANCR could greatly inhibit Huh7 and HepG2 cell proliferation. In addition, HCC cell apoptosis was increased by silence of DANCR and meanwhile, cell cycle progression was blocked in G1 phase. Apart from these, downregulation of DANCR repressed HCC cell migration and invasion ability obviously. As predicted by the bioinformatics analysis, microRNA-216a-5p (miR-216a-5p) could serve as a direct target of DANCR. MiR-216a-5p has been reported to be involved in many cancers. Here, the correlation between miR-216a-5p and DANCR was confirmed using dual-luciferase reporter assay and radioimmunoprecipitation assay. Subsequently, Kruppel-like factor 12 (KLF12) exerts an important role in different tumor types. KLF12 can function as a downstream target of miR-216a-5p. Finally, the in vivo experiments were used and the data proved that DANCR also strongly suppressed HCC tumor growth in vivo via targeting miR-216a-5p and KLF12. In conclusion, our study indicated that DANCR might provide a new perspective for HCC treatment.

RBOHF from Arabidopsis thaliana represents a multifunctional NADPH oxidase regulating biotic and abiotic stress tolerance, developmental processes and guard cell aperture. The molecular components and mechanisms determining RBOHF activity remain to be elucidated. Here we combined protein interaction studies, biochemical and genetic approaches, and pathway reconstitution analyses to identify and characterize proteins that confer RBOHF regulation and elucidated mechanisms that adjust RBOHF activity. While the Ca2+ sensor-activated kinases CIPK11 and CIPK26 constitute alternative paths for RBOHF activation, the combined activity of CIPKs and the kinase open stomata 1 (OST1) triggers complementary activation of this NADPH oxidase, which is efficiently counteracted through dephosphorylation by the phosphatase ABI1. Within RBOHF, several distinct phosphorylation sites (p-sites) in the N-terminus of RBOHF appear to contribute individually to activity regulation. These findings identify RBOHF as a convergence point targeted by a complex regulatory network of kinases and phosphatases. We propose that this allows for fine-tuning of plant reactive oxygen species (ROS) production by RBOHF in response to different stimuli and in diverse physiological processes.

The foldable lithium-air batteries with high theoretical specific energy show wide application in portable electronic devices, and the flexible cathodes play the most important roles. In this work, CeO2 microspheres are in-situ grown on three-dimensional inter-connected graphene foam through hydrothermal treatment as the flexible cathode for lithium-air batteries. With the assistance of macroporous framework for rapid O2 diffusion and uniformly distributed CeO2 for enhanced catalytic activity towards oxygen reduction reaction, the lightweight flexible cathodes show a large discharge capacity of 3250 mAh·g-1 at current density of 200 mA·g-1 (based on the whole cathode), and can cycle steadily for 80 times with the capacity limitation of 600 mAh·g-1. The flexible lithium-air battery based on the novel cathodes also shows a stable discharge/charge potential platform during bending process and good electrochemical reversibility after bending for at least 1000 times in ambient air. The study reveals that the high catalytic flexible cathode would be suitable for foldable lithium-air batteries.

The toxicity of lead present in organohalide perovskites and the hazardous solvent system used for their synthesis hinders the deployment of perovskite solar cells (PSCs). Here, we report an environmentally friendly route for synthesis of bismuth based lead-free (CH3NH3)3Bi2I9 perovskites that utilize ethanol as the solvent. Using this method, dense and homogeneous microstructure was obtained, compared the porous rough microstructure obtained by DMF solution. Thus, the photovoltaic performance was enhanced and open voltage as high as 0.84 V can be obtained.

The electrochemical performance of non-aqueous lithium-oxygen battery depends largely on the catalytic activity of the cathode, among which the architecture design plays an important role. In this paper, we present a novel free-standing, flexible cathode with needle-like NiCo2O4 coated on three-dimensional graphene framework. The hierarchical structure exhibits macropores nest of graphene foam along with mesopores decoration of NiCo2O4 nanorods, which can provide fast diffusion or adsorption for the reactants, and abundant active site for oxygen reduction reaction and oxygen evolution reaction. With the novel cathode, the battery delivers a capacity about 5000 mAh·g-1 at current density 400 mA·g-1, and can cycle stably for at least 80 times without obviously degradation at the capacity limitation of 1000 mAh·g-1. This flexible cathode shows potential application in foldable electronic device.

BACKGROUND Cytochrome P450s are associated with the metabolising of a wide range of compounds, including insecticides. CYP353D1v2 has been found to be overexpressed in an imidacloprid-resistant strain of Laodelphax striatellus. Thus, this study was conducted to express CYP353D1v2 in Sf9 cells as a recombinant protein, to assess its ability to metabolise imidacloprid. RESULTS Western blot and carbon monoxide difference spectrum analysis indicated that the intact CYP353D1v2 protein had been successfully expressed in Sf9 insect cells. Catalytic activity tests with four traditional P450-activity-probing substrates found that the expressed CYP353D1v2 preferentially metabolised p-nitroanisole, ethoxycoumarin and ethoxyresorufin with specific activities of 32.70, 0.317 and 1.22 pmol min−1 pmol−1 protein respectively, but no activity to luciferin-H EGE. The enzyme activity for degrading imidacloprid was tested by measuring substrate depletion and formation of the metabolite. Kinetic parameters for imidacloprid were Km 5.99 ± 0.95 µm and kcat 0.03 ± 0.0004 min−1. The chromatogram analysis showed clearly the NADPH-dependent depletion of imidacloprid and the formation of an unknown metabolite. The UPLC-MS mass spectrum demonstrated that the metabolite was an oxidative product of imidacloprid, 5-hydroxy-imidacloprid. CONCLUSION These results suggest that CYP353D1v2 in L. striatellus is capable of degrading imidacloprid, and that enzyme activity can be evaluated well only by some traditional probing substrates. © 2017 Society of Chemical Industry

ATP-binding cassette (ABC) transporters are membrane-bound proteins involved in the movement of various substrates, including drugs and insecticides, across the lipid membrane. Demonstration of the role of human ABC transporters in multidrug resistance has led to speculation that they might be an important mechanism controlling the fate of insecticides in insects. However, the role of ABC transporters in insects remains largely unknown. The small brown planthopper, Laodelphax striatellus Fallen, has developed resistance to most of the insecticides used for its control. Our goals were to identify the ABC transporters in La. striatellus and to examine their involvement in resistance mechanisms, using related strains resistant to chlorpyrifos, deltamethrin and imidacloprid, compared with the susceptible strain. Based on the transcriptome of La. striatellus, 40 full-length ABC transporters belonging to the ABCA-ABCH subfamilies were identified. Quantitative PCR revealed that over 20% of genes were significantly up-regulated in different resistant strains, and eight genes from the ABCB/C/D/G subfamilies were up-regulated in all three resistant strains, compared with the susceptible strain. Furthermore, synergism studies showed verapamil significantly enhanced insecticide toxicity in various resistant strains but not in the susceptible strain. These results suggest that ABC transporters might be involved in resistance to multiple insecticides in La. striatellus.

As anode-support materials for solid oxide fuel cells, porous LaNbO4–NiO–Y2O3 stabilized ZrO2 (YSZ) composites (LNY), containing 0, 5, 10, 15, and 20 wt% of LaNbO4 and designated as 0LNO, 5LNO, 10LNO, 15LNO, and 20LNO, respectively, are prepared by tape casting and sintering. They are investigated for their microstructure and mechanical, electrical and thermal expansion properties. The porosity of as-sintered LNY is around 30%, and that of reduced LNY cermets decreases from 47% for reduced 0LNO to 43% for reduced 20LNO. The fracture strength (σf) of LNY is higher than that of the reduced form; however, both of them are not rather sensitive to the amount of LaNbO4, depending on crack-originating flaws in the specimens. The fracture toughness (KIC) of LNY increases with LaNbO4 content and is 1.87 MPa·m1/2 for 20LNO, which is more than 20% increase from that of 0LNO; however the KIC for reduced LNY is higher than that of LNY, and decreases with increasing LaNbO4 content due to the decreased amount of ductile metallic Ni phase. The conductivity of reduced LNY depends on Ni content and is higher than 289 S/cm at temperatures below 900°C. The coefficient of thermal expansion (CTE) of both LNY and reduced LNY is in the range between 12.4 and 11.4 × 10−6 K−1; which is closely matched with that of YSZ electrolyte.

The homogeneously deposition of quantum dots (QDs) on the mesoporous or one-dimensional TiO2 film with a well-covered layer has become one major challenge in quantum dot-sensitized solar cell (QDSSC). In this study, one-dimensional TiO2 nanorod arrays based photoanode prepared by a simple linker-assisted SILAR method is studied. The influence of the short organic ligand (TGA) on the homogeneity of QDs on TiO2 nanorod arrays is discussed and the photoelectrochemical performance of QDSSC is evaluated by UV–vis absorbance spectroscopy, current–voltage performance and electrochemical impedance spectroscopy. The results show that the TGA ligand can act as an efficient bridge between CdS QDs and TiO2, whereas the content and particle size of the QDs can be easily tuned by controlling the dipping time and SILAR cycle. Owing to the presence of TGA, the charge-transfer rate at CdS QDs and TiO2 interfacial region is noticeable enhanced.

In this study, the flow distribution in a planar solid oxide fuel cell (SOFC) stack with external manifolds is investigated by computational fluid dynamics (CFD) technique. Three dimensional external manifold models are constructed for a SOFC stack composed of 24 cells. CFD simulations with air as operating gas are implemented for two types of stacks with different inlet manifolds, including the manifold with three tube inlets (T-manifold) and the manifold with a gas chamber on top (C-manifold). The influences of different parameters such as channel resistance and gas feeding rate on flow distribution are studied. Modeling results indicate that the increase of channel resistance and a lower gas feeding rate can respectively improve the uniformity factor of T-manifold and C-manifold from 0.963 to 0.995 and 0.989 to 0.998. For a given channel resistance, the pressure distribution in the inlet manifold plays a dominant role in the flow distribution. In addition, flow distribution in the stack with C-manifold is generally more uniform than the stack with T-manifold. Furthermore, flow characteristics of the two type inlet manifolds are investigated by measuring velocity distribution of the gas at manifold outlets using a hot-wire anemometer.

Cyclosporin A (CsA) is a widely used immunosuppressive agent that also causes hypertension. However, the molecular basis for CsA-induced hypertension remains elusive. In this study, we established an in vitro model for CsA-induced pathological changes in vasculature. Rat mesenteric arteries were incubated with CsA for 24 hr in an organ culture system. Both vasocontraction and vasorelaxation in mesenteric artery were studied using myograph technology, and mRNA expressions of the contractile receptors were determined by real-time PCR. The results showed that CsA increased the mRNA expression and contractile function of several G-protein-coupled receptors (GPCRs), such as endothelin receptor type B (ETB ), 5-hydroxytryptamine type 1B (5-HT1B ) and 1D (5-HT1D ), in vascular smooth muscle cells. In addition, both nitric oxide (NO)-mediated vasorelaxation and endothelium-independent relaxation were impaired by CsA. In summary, this study showed the enhanced GPCRs-mediated contraction and reduced vasorelaxation in mesenteric artery after organ culture with CsA, which mimicked the CsA-induced pathological changes in the vascular system in vivo. Furthermore, this organ culture system would be an ideal in vitro tool to study the molecular mechanisms of CsA-induced hypertension.

BACKGROUND One of the key limiting factors for using RNA interference technology to develop new pest control practices is the toxicological effectiveness. In order to explore potential methods to improve the efficiency of RNAi in insects, we cloned two dsRNA binding proteins from Laodelphax striatellus and investigated their functions. RESULTS In this study, the genes homologous to the dsRNA binding proteins TRBP and STAU in L. striatellus were first cloned and designated as LsTRBP and LsSTAU. Using the chitinase gene Chi, which has been confirmed to have lethal effects when knocked down by RNAi, as a reporter, the functions of these two dsRNA binding proteins were then investigated by using dsRNA feeding. The results showed that feeding with dsChi alone caused significant lethal effects, with a mortality four-fold higher than that of the control, whereas feeding with dsTRBP or dsSTAU alone did not yield any significant lethal effects. When dsChi was fed in the mixture 1:1 with dsSTAU, it also resulted in high mortality, which was a little lower than feeding with dsChi alone, but not statistically significant. However, when fed in the 1:1 mixture with dsTRBP, the lethal effect of dsChi was completely eliminated. Further analysis of gene expression found that single dsRNA depressed only its own target gene. When treated in 1:1 mixture, dsSTAU or dsChi did not change significantly the depression of the other dsRNA, but dsTRAB counteracted almost all the effect of dsChi. CONCLUSION These results indicate that the loss of LsTRBP can significantly inhibit dsChi-mediated genetic interference. These findings not only suggest that the LsTRBP gene in L. striatellus plays an important role in regulating RNAi but also imply that the metabolic regulation of dsRNAs with respect to genetic interference in L. striatellus is similar to that in higher animal species. © 2013 Society of Chemical Industry

Here, we report a novel double-layer structure photoanode with TiO2 nanotube (TNT) layer and TiO2 nanoparticle (TP) layer via a two-step method of electrochemical anodization and screen printing for dye-sensitized solar cells (DSSCs). The results indicate that DSSCs with this double-layer structure have significant advantages of large surface area, long electron lifetime, superior electron recombination restraint characteristics, and high light scattering. The layer thickness of nanotubes and nanoparticles is also investigated and finally an optimized double-layer structure with excellent performance is prepared. With such a double-layer structure photoanode, DSSC with a relative high conversion efficiency of 6.43% and a short-circuit photocurrent density of 16.40 mA·cm−2 is obtained.

Photoanodes for flexible DSSC have been prepared through a chemical sintering method using hydrothermal cement at low temperature of 120 degrees C. The addition of the hydrothermal cement can effectively increase the adhesion between the photoanode and flexible ITO-PET substrate and build the interconnection between nanoparticles at low temperature for the fast transport of electrons. The flexible DSSC based on the photoanode obtains a relatively high photo-to-electric conversion efficiency of 4.0%. The method basing on the commercially available TiO2 with a small proportion of hydrothermal cement is suitable for roll-to-roll screen-printing preparation, which is expected to be scaled up for mass production of high performance flexible DSSCs.

The time-constraint data traffic is very common in vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) communications. Time-constraint flows are those who have fixed start and stop times and try to maximize the transferred data volume during the limited connection time. From the view of users, the total data transmitted by each flow should be proportional to each one's holding time if the network resources are allocated fairly. However, we find that the traditional fairness concept solely based on flow rates is not suitable for this scenario. Therefore, we redefine the fairness concept regarding the application utility for time-constraint flows. According to this new utility-based fairness definition, we propose two practical bandwidth sharing schemes for transferring data by fast-moving wireless nodes such as vehicles. Simulations through ns-2 show that the proposed algorithms can achieve better utility fairness than the standard TCP and are also friendly to TCP in the long term. Copyright © 2010 John Wiley & Sons, Ltd.

New energy storage and conversion systems require large-scale, cost-effective, good safety, high reliability, and high energy density. This study demonstrates a low-cost and safe aqueous rechargeable lithium-nickel (Li-Ni) battery with solid state Ni(OH)2/NiOOH redox couple as cathode and hybrid electrolytes separated by a Li-ion-conductive solid electrolyte layer. The proposed aqueous rechargeable Li-Ni battery exhibits an approximately open-circuit potential of 3.5 V, outperforming the theoretic stable window of water 1.23 V, and its energy density can be 912.6 W h kg-1, which is much higher than that of state-of-the-art lithium ion batteries. The use of a solid-state redox couple as cathode with a metallic lithium anode provides another postlithium chemistry for practical energy storage and conversion.