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The black carabid beetle Calosoma maximoviczi is a successful predator that serves as both a beneficial insect and a severe threat to economic herbivores. Its hunting technique relies heavily on olfaction, but the underlying mechanism has not been studied. Here, we report the electrophysiological, ecological and molecular traits of bioactive components identified from a comprehensive panel of natural odorants in the beetle-prey-plant system. The aim of this work was to investigate olfactory perceptions and their influence on the behaviours of C. maximoviczi.Among the 200 identified volatiles, 18 were concentrated in beetle and prey samples, and 14 were concentrated in plants. Insect feeding damage to plants led to a shift in the emission fingerprint. Twelve volatiles were selected using successive electrophysiological tests. Field trials showed that significant sex differences existed when trapping with a single chemical or chemical mixture. Expression profiles indicated that sex-biased catches were related to the expression of 15 annotated CmaxOBPs and 40 CmaxORs across 12 chemosensory organs. In silico evaluations were conducted with 16 CmaxORs using modelling and docking. Better recognition was predicted for the pairs CmaxOR5-(Z)-3-hexenyl acetate, CmaxOR6-β-caryophyllene, CmaxOR18-(E)-β-ocimene and CmaxOR18-tetradecane, with higher binding affinity and a suitable binding pocket. Lastly, 168Y in CmaxOR6 and 142Y in CmaxOR18 were predicted as key amino acid residues for binding β-caryophyllene and tetradecane, respectively.This work provides an example pipeline for de novo investigation in C. maximoviczi baits and the underlying olfactory perceptions. The results will benefit the future development of trapping-based integrated pest management strategies and the deorphanization of odorant receptors in ground beetles. © 2022 Society of Chemical Industry.

Sex pheromones are pivotal for insect reproduction. However, the mechanism of sex pheromone communication remains enigmatic in hymenopteran parasitoids. Here we have identified the sex pheromone and elucidated the olfactory basis of sex pheromone communication in Campoletis chlorideae (Ichneumonidae), a solitary larval endoparasitoid of over 30 lepidopteran pests. Using coupled gas chromatography-electroantennogram detection, we identified two female-derived pheromone components, tetradecanal (14:Ald) and 2-heptadecanone (2-Hep) (1:4.6), eliciting strong antennal responses from males but weak responses from females. We observed that males but not females were attracted to both single components and the blend. The hexane-washed female cadavers failed to arouse males, and replenishing 14:Ald and 2-Hep could partially restore the sexual attraction of males. We further expressed six C. chlorideae male-biased odorant receptors in Drosophila T1 neurons and found that CchlOR18 and CchlOR47 were selectively tuned to 14:Ald and 2-Hep, respectively. To verify the biological significance of this data, we knocked down CchlOR18 and CchlOR47 individually or together in vivo and show that the attraction of C. chlorideae to their respective ligands was abolished. Moreover, the parasitoids defective in either of the receptors were less likely to court and copulate. Finally, we show that the sex pheromone and ( Z )-jasmone, a potent female attractant, can synergistically affect behaviors of virgin males and virgin females and ultimately increase the parasitic efficiency of C. chlorideae . Our study provides new insights into the molecular mechanism of sex pheromone communication in C. chlorideae that may permit manipulation of parasitoid behavior for pest control.

Biomimetic nanoparticles obtained from bacteria or viruses have attracted substantial interest in vaccine research and development. Outer membrane vesicles (OMVs) are mainly secreted by gram-negative bacteria during average growth, with a nano-sized diameter and self-adjuvant activity, which may be ideal for vaccine delivery. OMVs have functioned as a multifaceted delivery system for proteins, nucleic acids, and small molecules. To take full advantage of the biological characteristics of OMVs, bioengineered Escherichia coli-derived OMVs were utilized as a carrier and SARS-CoV-2 receptor-binding domain (RBD) as an antigen to construct a "Plug-and-Display" vaccine platform. The SpyCatcher (SC) and SpyTag (ST) domains in Streptococcus pyogenes were applied to conjugate OMVs and RBD. The Cytolysin A (ClyA) gene was translated with the SC gene as a fusion protein after plasmid transfection, leaving a reactive site on the surface of the OMVs. After mixing RBD-ST in a conventional buffer system overnight, covalent binding was formed between the OMVs and RBD. Thus, a multivalent-displaying OMV vaccine was achieved. By replacing with diverse antigens, the OMVs vaccine platform can efficiently display a variety of heterogeneous antigens, thereby potentially rapidly preventing infectious disease epidemics. This protocol describes a precise method for constructing the OMV vaccine platform, including production, purification, bioconjugation, and characterization.

The fall armyworm, Spodoptera frugiperda (J. E. Smith), is a polyphagous moth species that is spreading all around the globe. It uses (Z)-9-tetradecenyl acetate (Z9-14:Ac) and (Z)-7-dodecenyl acetate (Z7-12:Ac) (100:3.9) as essential sex pheromone components. However, our understanding of the molecular basis of pheromone detection of S. frugiperda is still incomplete.Herein, we identified six PRs, i.e. SfruOR6, 11, 13, 16, 56, and 62, by transcriptome sequencing. Subsequently, we heterologously expressed them in Drosophila OR67d neurons and determined their response spectra with a large panel of sex pheromones and analogs. Among them, SfruOR13-expressing neurons strongly respond to the major sex pheromone component Z9-14:Ac, but also comparably to (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:Ac) and weakly to (Z)-9-dodecenyl acetate (Z9-12:Ac). Both SfruOR56 and SfruOR62 are specifically tuned to the minor sex pheromone component Z7-12:Ac with varying intensities and sensitivities. In addition, SfruOR6 is activated only by Z9,E12-14:Ac, and SfruOR16 by both (Z)-9-tetradecenol (Z9-14:OH) and (Z)-9-tetradecenal (Z9-14:Ald). However, the OR67d neurons expressing SfruOR11 remain silent to all compounds tested, a phenomenon commonly found in the OR11 clade of Noctuidae species. Next, using single sensillum recording, we characterized four sensilla types on the antennae of males, namely A, B, C and D types that are tuned to the ligands of PRs, thereby confirming that S. frugiperda uses both SfruOR56 and SfruOR62 to detect Z7-12:Ac. Finally, using wind tunnel assay, we demonstrate that both Z9,E12-14:Ac and Z9-14:OH act as antagonists to the sex pheromone.We have deorphanized five PRs and characterized four types of sensilla responsible for the detection of pheromone compounds, providing insights into the peripheral encoding of sex pheromones in S. frugiperda.

Glucosinolates are token stimuli in host selection of many crucifer specialist insects, but the underlying molecular basis for host selection in these insects remains enigmatic. Using a combination of behavioral, electrophysiological, and molecular methods, we investigate glucosinolate receptors in the cabbage butterfly Pieris rapae. Sinigrin, as a potent feeding stimulant, elicited activity in larval maxillary lateral sensilla styloconica, as well as in adult medial tarsal sensilla. Two P. rapae gustatory receptor genes PrapGr28 and PrapGr15 were identified with high expression in female tarsi, and the subsequent functional analyses showed that Xenopus oocytes only expressing PrapGr28 had specific responses to sinigrin; when ectopically expressed in Drosophila sugar sensing neurons, PrapGr28 conferred sinigrin sensitivity to these neurons. RNA interference experiments further showed that knockdown of PrapGr28 reduced the sensitivity of adult medial tarsal sensilla to sinigrin. Taken together, we conclude that PrapGr28 is a gustatory receptor tuned to sinigrin in P. rapae, which paves the way for revealing the molecular basis of the relationships between crucifer plants and their specialist insects.

An RNA-involved phase-separation model has been proposed for transcription control. Yet, the molecular links that connect RNA binding to the transcription machinery remain missing. Here we find RNA-binding proteins (RBPs) constitute half of the chromatin proteome in embryonic stem cells (ESCs), and some are colocalized with RNA polymerase (Pol) II at promoters and enhancers. Biochemical analyses of representative RBPs—such as PSPC1 and PTBP1—show that the paraspeckle protein PSPC1 not only prevents the RNA-induced premature release of Pol II, and also makes use of RNA as multivalent molecules to promote Pol II engagement and activity, by enhancing the phase separation and subsequent phosphorylation and release of polymerase condensates. In ESCs, auxin-induced acute degradation of PSPC1 leads to genome-wide defects in Pol II phosphorylation and chromatin-binding and nascent transcription. We propose that the synergistic interplay of RBPs and RNA aids in the rate-limiting step of polymerase condensate formation to promote active transcription.

Feeding and oviposition deterrents help phytophagous insects to identify host plants. The taste organs of phytophagous insects contain bitter gustatory receptors (GRs). To explore their function, the GRs in Plutella xylostella were analyzed. Through RNA sequencing and qPCR, we detected abundant PxylGr34 transcripts in the larval head and adult antennae. Functional analyses using the Xenopus oocyte expression system and 24 diverse phytochemicals showed that PxylGr34 is tuned to the canonical plant hormones brassinolide (BL) and 24-epibrassinolide (EBL). Electrophysiological analyses revealed that the medial sensilla styloconica of 4th instar larvae are responsive to BL and EBL. Dual-choice bioassays demonstrated that BL inhibits larval feeding and female oviposition. Knock-down of PxylGr34 by RNAi attenuates the taste responses to BL, and abolishes BL-induced feeding inhibition. These results increase our understanding of how herbivorous insects detect compounds that deter feeding and oviposition, and may be useful for designing plant hormone-based pest management strategies., eLife digest Plant-eating insects use their sense of taste to decide where to feed and where to lay their eggs. They do this using taste sensors called gustatory receptors which reside in the antennae and legs of adults, and in the mouthparts of larvae. Some of these sensors detect sugars which signal to the insect that the plant is a nutritious source of food. While others detect bitter compounds, such as poisons released by plants in self-defense. One of the most widespread plant-eating insects is the diamondback moth, which feeds and lays its eggs on cruciferous vegetable crops, like cabbage, oilseed rape and broccoli. Before laying its eggs, female diamondback moths pat the vegetable’s leaves with their antennae, tasting for the presence of chemicals. But little was known about the identity of these chemicals. Cabbages produce large amounts of a hormone called brassinolide, which is known to play a role in plant growth. To find out whether diamondback moths can taste this hormone, Yang et al. examined all their known gustatory receptors. This revealed that the adult antennae and larval mouthparts of these moths make high levels of a receptor called PxylGr34. To investigate the role of PxylGr34, Yang et al. genetically modified frog eggs to produce this receptor. Various tests on these receptors, as well as receptors in the mouthparts of diamondback larvae, showed that PxylGr34 is able to sense the hormone brassinolide. To find out how this affects the behavior of the moths, Yang et al. investigated how adults and larvae responded to different levels of the hormone. This revealed that the presence of brassinolide significantly decreased both larval feeding and the amount of eggs laid by adult moths. Farmers already use brassinolide to enhance plant growth and protect crops from stress. These results suggest that the hormone might also help to shield plants from insect damage. However, more research is needed to understand how this hormone acts as a deterrent. Further studies could improve understanding of insect behavior and potentially identify more chemicals that can be used for pest control.

Background Long non-coding RNA (lncRNA) small nucleolar RNA host gene 17 (SNHG17) is a carcinogenic lncRNA in diverse cancers. The expression pattern and mechanisms of SNHG17 in glioma still await verification. Methods Paired glioma samples were enrolled. SNHG17, miR-23b-3p, and zinc-fingers and homeoboxes 1 (ZHX1) mRNA expression were examined by a quantitative real-time polymerase chain reaction (qRT-PCR). SNHG17 short hairpin RNA (shRNA) and miR-23b-3p mimics were transfected into LN229 and U251 cell lines to repress SNHG17 and up-regulate miR-23b-3p expression, respectively. Proliferation, migration and invasion of LN229 and U251 cells were probed by a cell counting kit-8 assay and a Transwell assay. Bioinformatics prediction, dual-luciferase reporter assay, RNA immunoprecipitation assay, qRT-PCR and western blotting were applied to determine the regulatory relationships among SNHG17, miR-23b-3p and ZHX1. Results SNHG17 expression was markedly raised in glioma tissues, which was positively correlated with ZHX1 expression and negatively associated with the expression of miR-23b-3p. After transfection of SNHG17 shRNAs into glioma cells, the proliferation, migration and invasion of cancer cells was markedly restrained. miR-23b-3p mimics the function of SHNG17 knockdown. Furthermore, miR-23b-3p was shown to be negatively modulated by SNHG17, and ZHX1 was identified as a target of miR-23b-3p. Conclusions SNHG17 is a "competing endogenous RNA" with respect to modulating ZHX1 expression by adsorbing miR-23b-3p and thereby promoting glioma progression.

Aminovinyl-cysteine residues arise from processing the C-terminal l-Cys and an internal l-Ser/l-Thr or l-Cys of a peptide. Formation of these nonproteinogenic amino acids, which occur in a macrocyclic ring of diverse ribosomally synthesized lanthipeptides and non-lanthipeptides, remains poorly understood. Here, we report that LanD-like flavoproteins in the biosynthesis of distinct non-lanthipeptides share an unexpected dual activity for aminovinyl-cysteine formation. Each flavoprotein catalyzes oxidative decarboxylation of the C-terminal l-Cys and couples the resulting enethiol nucleophile with the internal residue to afford a thioether linkage for peptide cyclization. The cyclization step, which largely depends on proximity effect by positioning the enethiol intermediate with a bent conformation at the active site, can be substrate-dependent, proceeding inefficiently through nucleophilic substitution for an unmodified peptide or efficiently through Michael addition for a dehydrated/dethiolated peptide. Uncovering this unusual flavin-dependent paradigm for thioether residue formation advances the understanding in the biosynthesis of aminovinyl-cysteine-containing RiPPs and renews interest in flavoproteins, particularly those involved in non-redox transformations. LanD-like flavoproteins activity, which is flexible in peptide substrate and amenable for evolution by engineering, can be combined with different post-translational modifications for structural diversity, thereby holding promise for peptide macrocyclization/functionalization in drug development by chemoenzymatic or synthetic biology approaches.

Various insect species including moths have shown significant foraging preference to acetic acid. However, the olfactory reception and behavioral outputs of acetic acid in moths remain unsolved. The female adults of Oriental armyworm, Mythimna separata, exhibit high preference to acetic acid enriched sweet vinegar solutions, making them good targets for exploration of acid reception and performance. We first proved that acetic acid is an essential component which elicited electrophysiological responses from volatiles of the sweet vinegar solution. Successive single sensillum recording tests showed that at least 4 types (as1, as2, as3, and as4) of sensilla were involved in acetic acid reception in the antennae. The low dosages of acetic acid elicited upwind flight and close search, and pre-contact proboscis extension responses of the fasted females, indicating it serves as a food related olfactory cue. In vivo optical imaging data showed that low dosages of acetic acid activated one ordinary glomerulus (DC3), and high dosages evoked additional two glomeruli (DC1 and AC1) in the antennal lobe. A systematic survey on olfaction related receptors in three related transcriptomes has yielded 67 olfactory receptors (ORs) and 19 ionotropic receptors (IRs). Among, MsepIR8a, MsepIR64a, MsepIR75q1, and MsepIR75q2 were chosen as putative acid receptors by blasting against known acid IRs in Drosophila and comparing essential amino acid residues which related to acid sensing. Later in situ hybridization revealed that MsepIr8a was co-expressed with each of the other 3 Irs, suggesting its putative co-receptor role. This study reveals olfactory reception of acetic acid as an attractant in M. separata, and it provides the solid basis for later deorphanization of relevant receptors.

Properties of metal particles (MPs) are largely dependent on preparation method and morphology. Herein, we report a new facile synthesis route of silver particles (AgPs) in which growth pattern of AgPs can be easily controlled and some novel morphologies are achieved. In this strategy, cheap organic acids are selected as growth regulators for the morphology control of AgPs, and the concentration of organic acid plays a key role in the formation of AgPs. Furthermore, the effects of number of carbon atom in organic acids on the morphology of AgPs were investigated. With increase of number of carbon atom in organic acids, the morphology of AgPs will change from plate to sphere. These results presented here are vital to both exploration of growth theory and constructing novel morphologies of AgPs not only in this paper but also possibly other system. Moreover, catalytic activity of these prepared AgPs was studied toward reduction of p -nitrophenol by NaBH 4 .

Based on the entity model of the type 4B26 diesel engine, calculated by CFD FIRE and combined with the software BOOST for the initial boundary conditions, the influence of combustion chamber structural parameters, such as boss height, surface-volume ratio and diameter-depth ratio of combustion chamber, on in-cylinder flow field of diesel engine was investigated. The results show that the influence of the boss height on flow field in the cylinder and the transient swirl ratio is obvious, and increasing the boss height is beneficial to urge the formation of mixture rapidly. Reducing the surface-volume ratio is beneficial for improving the maximum transient swirl ratio, and the air strength maintains well also, but has little influence to the retentivity of the swirl intensity. Meanwhile, reducing the diameter-depth ratio does not only improves the air flow movement strengthen in the combustion chamber, but also enhances the maximum transient swirl ratio, and the retentivity of swirl flow movement is satisfying.

The leaching behavior of hexavalent chromium (Cr(VI)) and major metal elements relevant to Cr(VI) leaching from chromite ore processing residue (COPR) to HNO3 are investigated by batch leaching tests. According to the test results, aqueous Cr(VI) accounted for 70-80% of the content of total Cr. Cr(VI) concentration was controlled by the dissolution degree of Cr(VI)-bearing minerals (such as hydroandradite) as the pH value ranged from 7.58 to 10.47, and by the adsorption degree of Cr(VI) on metal amorphous precipitates as pH value ranged from 6.18 to 7.58. It takes time for the penetration of acid into COPR and the release of alkalinity from the interior zone of particles. So, it could be speculated that the fine-sized particles would react with acid more effectively. 14mol HNO3 per 1kg COPR is needed to maintain the pH value to achieve 7.5 for 48 hours. This indicates the acid neutralization capacity of the test sample is relatively large. It suggests that the application of acid treatment method for COPR disposal is feasible but costly.

In this paper, one-dimensional parabolic equations is studied .A high accuracy method for solving one-dimensional parabolic equations is structured by choosing suitable parameters, its accuracy is better-then- third-order in time and space direction.

In molecular dynamics, molecular mechanics and quantum mechanics for a complicated system, most of the numerical calculations are at the Lennard-Jones potential. So, effective treatment of Lennard-Jones potential shows an important role. This paper presents an effective algorithm for the optimization of Lennard-Jones potential. The algorithm is a genetic-based algorithm associated with the owerful discrete gradient method and the correct choice of initial coordinates. Numerical results show the effectiveness of the present algorithm and new bestresults for 39,40,42,48,55,75,76,97 atoms were found. These results might be used to study the structure of spherical viruses and molecules.

The Lennard-Jones (LJ) Potential Energy Problem is to construct the most stable form of N atoms of a molecule with the minimal LJ potential energy. This problem has a simple mathematical form Minimize subject to Where ,is the coordinates ofatom. This paper is to minimize the L-J potential on ,where n = 3N. however it is a challenging and diffcult problem for many optimization methods when N is larger. This paper presents an effective mathematical optimization algorithm for minimizing the LJ Potential and a series of elegant optimal solutions of atoms up to 310 were got.

The effects of rare earth elements (REEs) (like Y, Ce, Nd and Dy) on the microstructure and mechanical properties of cast NiAl-28Cr-5.5Mo-0.5Hf alloy were investigated. The results suggest that the microstructure of REEs-doped alloys gradually refines with increasing REEs addition and the appropriate addition of REEs can improve the compressive ductility and yield strength at room temperature. In addition, REEs additions increase the elevated temperature strength and deformation ability of the alloys. The elevated temperature compression deformation behavior of Nd-doped alloy can be property described by power-law equation. (c) 2006 Elsevier Ltd. All rights reserved.

The stress change-strain transient creep experiment was conducted and the side surface of creep-rupture samples was examined in order to study the apparent creep activation energy for NiAl–9Mo alloy. Most of the recoverable strain is established and the strain rate decreases sharply during the initial deformation after unloading the major stress. The magnitude of the recoverable deformation increases only slightly and the strain rate changes slowly during the following course. The relationship between recoverable strain rate and relax time during the relative steady-state stage is fitted in the equation ɛ˙r=Atm (A=1.294E−4, m=−0.450). The backflow process is temperature dependent and is controlled by the flow behavior of the matrix material. The apparent creep activation energy under constant stress is a combination of the activation energy for creep flow of the matrix and that for the damage process at the interface.

Objective To study the chemical constituents from the barks of Mangifera indica. Methods The constituents were separated and purified by different methods of chromatography, and their structures were elucidated by IR, MS, 1D and 2D NMR techniques. Results Six compounds were isolated from the barks of M. indica. Their structures were identified as mangiferone ( 1 ), mangiferin ( 2 ), myricetin ( 3 ), myricitrin ( 4 ), rutin ( 5 ), and quercetin ( 6 ). Conclusion Mangiferone ( 1 ) is a new diarylheptanoid compound isolated from the barks of M. indica.

The brittle-to-ductile transition (BDT) behavior of NiAl–9Mo alloys was firstly investigated to occur in the small temperature range of about 10 °C using tensile test method. The characteristic temperature T AB was defined for BDT in the alloy. It associates with the temperature at which the resistance to cleavage starts to sharply increase and the massive dislocation suddenly generates. Therefore, T AB is the critical temperature which symbolizes that the material undergoes the brittle-to-ductile transition.

In this paper we study the existence of solutions for random multi-valued integrodifferendifferential periodic systems. We prove the existence theorems under most common hypotheses for the convex and non-convex problems. An application to random periodic feedback control system is also considered.

To investigate the effect of curcumin on indoleamine 2, 3 -dioxygenase (IDO) expression induced by IFN-gamma in cancer cells.A431, HeLa, HepG2, CNE2 cells were treated with curcumin for 24 hours, then the cell proliferation was detected by methyl thiazolyl tetrazolium (MTF) assay. The effects of curcumin on IDO expression induced by IFN-gamma in these cancer cells were demonstrated by Western blot. The transcription of interferon responsive factor-1 (IRF-1), which was a key transcription factor regulating IDO expression, was analyzed by reverse transcription polymerase chain reaction (RT-PCR) under the treatment of curcumin.Curcumin inhibited the expression of IDO in these cancer cells. However, curcumin did not inhibit the transcription of IRF-1 in cancer cells.Curcumin could inhibit the expression of IDO in cancer cells.

This paper further investigates the sub-gradient projection neural networks model for solving non- differentiable convex optimization problems proposed by Li et al. (2006). It is proved in this paper that when the initial points are belong to the constraint set or the initial points are not belong to the constraint set and the objective function is strictly convex, the network trajectories converge to an optimal solution of the primal optimal problem.

To analyze the chemical constituents of the non-alkaloid fraction of Uncaria macrophylla.The constituents were separated and purified by silica gel chromatography and recrystalization, and their structures were identified by infrared, mass and nuclear magnetic resonance spectrometry.Six compounds were isolated from the non-alkaloid fraction of Uncaria macrophylla, whose structures were identified as beta-sitosterol, beta-daucosterol, ursolic acid, alpha-amyrin acetate, 3beta, 6beta, 23-trihydroxyurs-12-en-28-oic acid, 3beta-hydroxyurs-12-en-27, and 3beta-hydroxyurs-12-en-27, 28-dioic acid, respectively.Ursolic acid is the main component in the non-alkaloid fraction of Uncaria macrophylla. Alpha-amyrin acetate and 3beta-hydroxyurs-12-en-27, 28-dioic acid are isolated and characterized for the first time from this plant.

For general fuzzy optimization problem, this paper gives comparison method of fuzzy information on synthesizing effect and operation of fuzzy optimization on principal indexes transformation by distinguishing principal indexes and assistant indexes. Then based on the weakness of the existing methods for processing fuzzy constraints, this paper proposes axiom system of fuzzy inequity degree, and gives an instructive metric method. The paper establishes fuzzy optimization model based on synthesizing effect and inequity degree, and gives concrete solution scheme based on genetic algorithm and principal operation. The analysis and discussion indicate that this optimization model and solution method can effectively process decision consciousness, and is a good operation.