Effects of Insecticides on Pest Populations and Their Natural Enemies in Soybean Field

In the 5-time field experiments and broad demonstrations, effects of volume and application formulae of several pesticides on the population densities of major inset pests and natural enemies in the soybean field were determined. Results from the Ducan’s multiple range test indicated that 300 g/ha of Omethoate (fine granule) and 45 g/ha of Fenvalerate in the seedling stage and 300 g/ha of Chloromethiuron suspensoid in the flowering stage may control pests and protect major natural enemies. Application of these pesticides in the corresponding soybean stages is an effective way that mediates the conflict between chemical and biological controls in the field. There are over 170 species of natural enemies whose hosts are known in the soybean field in China. These natural enemies play important roles in controlling the soybean pests. However, farmers still strongly rely on chemicals to control these pests because natural enemies are not able to timely curb the pest infestations when there is a pest outbreak. Frequent chemical application in a higher volume will ruin the ecological balance. The conflict between biological and chemical controls has become a hot issue in the soybean production worldwide. Our objectives in this study are to decide the effective low concentrations of commonly used pesticides, determine the effect of the third and fourth generations of pesticides on the major insect pests and natural enemies in the soybean field and propose feasible control methods by coordinating control and chemical controls.Originating text in Chinese.Citation: Qi, Yaoxun, Ma, Zhengquan, Shan, De'An, Gao, Xiaohua, Wang, Qisheng. (1987). Effects of Insecticides on Pest Populations and Their Natural Enemies in Soybean Field. Plant Protection (Institute of Plant Protection, CAAS, China), 13, 4-6

Evaluation of bistable systems versus matched filters in detecting bipolar pulse signals

This paper presents a thorough evaluation of a bistable system versus a matched filter in detecting bipolar pulse signals. The detectability of the bistable system can be optimized by adding noise, i.e. the stochastic resonance (SR) phenomenon. This SR effect is also demonstrated by approximate statistical detection theory of the bistable system and corresponding numerical simulations. Furthermore, the performance comparison results between the bistable system and the matched filter show that (a) the bistable system is more robust than the matched filter in detecting signals with disturbed pulse rates, and (b) the bistable system approaches the performance of the matched filter in detecting unknown arrival times of received signals, with an especially better computational efficiency. These significant results verify the potential applicability of the bistable system in signal detection field.Comment: 15 pages, 9 figures, MikTex v2.

A Method to Generate and Analyze Modified Myristoylated Proteins

Covalent lipid modification of proteins is essential to their cellular localizations and functions. Engineered lipid motifs, coupled with bio-orthogonal chemistry, have been utilized to identify myristoylated or palmitoylated proteins in cells. However, whether modified proteins have similar properties as endogenous ones has not been well investigated mainly due to lack of methods to generate and analyze purified proteins. We have developed a method that utilizes metabolic interference and mass spectrometry to produce and analyze modified, myristoylated small GTPase ADP-ribosylation factor 1 (Arf1). The capacities of these recombinant proteins to bind liposomes and load and hydrolyze GTP were measured and compared with the unmodified myristoylated Arf1. The ketone-modified myristoylated Arf1 could be further labeled by fluorophore-coupled hydrazine and subsequently visualized through fluorescence imaging. This methodology provides an effective model system to characterize lipid-modified proteins with additional functions before applying them to cellular systems

Immunization with Fc-based recombinant Epstein-Barr virus gp350 elicits potent neutralizing humoral immune response in a BALB/c mice model

Epstein-Barr virus (EBV) was the first human virus proved to be closely associated with tumor development, such as lymphoma, nasopharyngeal carcinoma (NPC) and EBV-associated gastric carcinoma. Despite many efforts to develop prophylactic vaccines against EBV infection and diseases, no candidates have succeeded in effectively blocking EBV infection in clinical trials. Previous investigations showed that EBV gp350 plays a pivotal role in the infection of B lymphocytes. Nevertheless, using monomeric gp350 proteins as antigens has not been effective in preventing infection. Multimeric forms of the antigen are more potently immunogenic than monomers, however the multimerization elements used in previous constructs are not approved for human clinical trials. To prepare a much-needed EBV prophylactic vaccine that is potent, safe and applicable, we constructed an Fc-based form of gp350 to serve as a dimeric antigen. Here we show that the Fc-based gp350 antigen exhibits dramatically enhanced immunogenicity compared to wild-type gp350 protein. The complete or partial gp350 ectodomain was fused with the mouse IgG2a Fc domain. Fusion with the Fc domain did not impair gp350 folding, binding to a conformation-dependent neutralizing antibody and binding to its receptor by ELISA and SPR. Specific antibody titers against gp350 were notably enhanced by immunization with gp350-Fc dimers compared to gp350 monomers. Furthermore, immunization with gp350-Fc fusion proteins elicited potent neutralizing antibodies against EBV. Our data strongly suggest that an EBV gp350 vaccine based on Fc fusion proteins may be an efficient candidate to prevent EBV infection in clinical applications. Please click Additional Files below to see the full abstract

Structure–activity relationship studies of QS11, a small molecule Wnt synergistic agonist

Both the Wnt/β-catenin signaling pathway and small GTPases of the ADP-ribosylation factors (ARF) family play important roles in regulating cell development, homeostasis and fate. The previous report of QS11, a small molecule Wnt synergist that binds to ARF GTPase-activating protein 1 (ARFGAP1), suggests a role for ARFGAP1 in the Wnt/β-catenin pathway. However, direct inhibition of enzymatic activity of ARFGAP1 by QS11 has not been established. Whether ARFGAP1 is the only target that contributes to QS11's Wnt synergy is also not clear. Here we present structure-activity relationship (SAR) studies of QS11 analogs in two assays: direct inhibition of enzymatic activity of purified ARFGAP1 protein and cellular activation of the Wnt/β-catenin pathway. The results confirm the direct inhibition of ARFGAP1 by QS11, and also suggest the presence of other potential cellular targets of QS11

A novel vaccine candidate based on chimeric virus-like particle displaying multiple conserved epitope peptides induced neutralizing antibodies against EBV infection.

Epstein-Barr virus (EBV) is the causative pathogen for infectious mononucleosis and many kinds of malignancies including several lymphomas such as Hodgkin\u27s lymphoma, Burkitt\u27s lymphoma and NK/T cell lymphoma as well as carcinomas such as nasopharyngeal carcinoma (NPC) and EBV-associated gastric carcinoma (EBV-GC). However, to date no available prophylactic vaccine was launched to the market for clinical use

Localized High-Concentration Electrolytes Get More Localized Through Micelle-Like Structures

Liquid electrolytes in batteries are typically treated as macroscopically homogeneous ionic transport media despite having complex chemical composition and atomistic solvation structures, leaving a knowledge gap of microstructural characteristics. Here, we reveal a unique micelle-like structure in a localized high-concentration electrolyte (LHCE), in which the solvent acts as a surfactant between an insoluble salt in diluent. The miscibility of the solvent with the diluent and simultaneous solubility of the salt results in a micelle-like structure with a smeared interface and an increased salt concentration at the centre of the salt-solvent clusters that extends the salt solubility. These intermingling miscibility effects have temperature dependencies, wherein an exemplified LHCE peaks in localized cluster salt concentration near room temperature and is utilized to form a stable solid-electrolyte interphase (SEI) on Li-metal anode. These findings serve as a guide to predicting a stable ternary phase diagram and connecting the electrolyte microstructure with electrolyte formulation and formation protocols to form stable SEI for enhanced battery cyclability

PSR J1926-0652: A Pulsar with Interesting Emission Properties Discovered at FAST

We describe PSR J1926-0652, a pulsar recently discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Using sensitive single-pulse detections from FAST and long-term timing observations from the Parkes 64-m radio telescope, we probed phenomena on both long and short time scales. The FAST observations covered a wide frequency range from 270 to 800 MHz, enabling individual pulses to be studied in detail. The pulsar exhibits at least four profile components, short-term nulling lasting from 4 to 450 pulses, complex subpulse drifting behaviours and intermittency on scales of tens of minutes. While the average band spacing P3 is relatively constant across different bursts and components, significant variations in the separation of adjacent bands are seen, especially near the beginning and end of a burst. Band shapes and slopes are quite variable, especially for the trailing components and for the shorter bursts. We show that for each burst the last detectable pulse prior to emission ceasing has different properties compared to other pulses. These complexities pose challenges for the classic carousel-type models.Comment: 13pages with 12 figure