Effects of physical and social experiences and octopamine receptor agonist on fighting behavior of male crickets Velarifictorus aspersus (Orthoptera: Gryllidae)

Wei-Nan Kang,Yang Zeng,Dao-Hong Zhu 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.2

Fighting commonly occurs among animals and is very important for resolving conflicts between conspecific individuals over limited resources. The plasticity of fighting strategies and neurobiological mechanisms underlying fighting behavior of insects are not fully understood. In the present study, we examined whether physical and social experiences affected the aggressiveness of males of the cricket Velarifictorus aspersus Walker, and whether an octopamine (OA) receptor agonist could affected the aggressiveness of males exposed to different experiences. We found that flight and winning a fight significantly enhanced male aggressiveness, while losing a fight significantly suppressed male aggressiveness, consistent with the findings of existing studies on other cricket species. We also found that female presence had a stronger enhancing effect on male aggressiveness than flight or winning a fight. These findings demonstrated that physical and social experiences can affect the fighting behavior of male V. aspersus. Topical application of a 0.15M solution of an OA receptor agonist (chlordimeform, CDM) significantly increased male aggression level, suggesting that OA may play an important role as a neuromodulator in controlling fighting behavior of males of this species. Despite displaying a significantly higher aggression level (level 5 or 6), CDM-treated losers did not escalate to physical combat, while fights between courting males usually resulted in physical escalation. It is likely that fighting behavior is only partly regulated by OA, and additional regulatory pathways may be involved in achieving physical combat.

Anti-androgen-independent Prostate Cancer Effects of Ginsenoside Metabolites In Vitro: Mechanism and Possible Structure-Activity Relationship Investigation

Wei Li,Yong Liu,Jiang-Wei Zhang,Chun-Zhi Ai,Nan Xiang,Hui-Xin Liu,Ling Yang 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.1

Treatment of androgen-independent prostate cancer (AIPC) remains unsatisfactory. In our present experiment, natural occurring ginsenosides (NOGs) and intestinal bacterial metabolites (IBMs) were employed to investigate their anti-AIPC cell growth activity using PC-3 cells. Our results showed that the IBMs exerted more portent anti-AIPC activity than NOGs, by decreasing survival rate, inhibiting proliferation, inducing apoptosis, and leading to cell cycle arrest in AIPC PC-3 cells. The increase of LogP and decrease of C-6 steric hindrance, which were caused by deglycosylation by intestinal bacteria, may be the reason for the higher anti-AIPC activity of IBMs.

Nonlinear Instability of Angle Section Beams under Uniformly Distributed Loads

Wei-bin Yuan,Wei Zhang,Jie Xu,Nan-ting Yu 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.2

This paper presents a study on the flattening behavior of angle-section beams of finite length subjected to uniformly distributed transverse loads. Analytical solutions for static instabilities of angle-section beams when they are bent about their weak axis are derived using energy methods. The basic assumptions used in the present study are that the total strain energy of an angle-section beam subjected to a uniformly distributed load can be simplified into a two-stage process. One is the bending response of the two legs behaving as the plate; the other is the bending response as a beam with flattened section. The nonlinear instability is derived by applying the minimum potential energy principle and the corresponding static critical moments associated with the section flattening-induced buckling are determined. To validate the analytical solution developed, nonlinear finite element analyses are also conducted. Good agreement between the present solution and the FEA results is demonstrated.

Erinacene D, a new aromatic compound from Hericium erinaceum

Li, Wei,Sun, Ya Nan,Zhou, Wei,Shim, Sang Hee,Kim, Young Ho Springer Science and Business Media LLC 2014 The Journal of Antibiotics Vol.67 No.10

Synthesis of S-adenosyl-L-methionine in Escherichia coli

Xiao-Nan Wei,Minjie Cao,Jian Li,Huan Li,Yi Song,Cuihong Du 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.6

S-adenosyl-L-methionine (SAM) is an importantphysiological metabolite in vivo and may be useful inmedicines. SAM is produced from L-methionine and ATPcatalyzed by S-adenosyl-L-methionine synthetase (SAMS)in vivo. In this study, the gene encoding SAMS was clonedand a genetically engineered Escherichia coli (E. coli)BL21(pET-28a-SAMS) was constructed. The recombinantSAMS with a molecular mass of approximately 46 kDawas expressed by inducing the engineered E. coli usingisopropyl-β-D-1-thiogalactopyranoside (IPTG) as an inducer. To produce SAM using a low-cost, nontoxic and highperformanceexpression system, lactose was used as asubstitute for IPTG to induce BL21(pET-28a-SAMS). Byoptimizing the expression conditions, the concentration ofSAM produced by the engineered E. coli was 48 mg/L in theculture medium supernatant. To increase the concentrationof SAM produced, a coupled system was constructedconsisting of E. coli BL21(pET-28a-SAMS) and Saccharomycescerevisiae (S. cerevisiae) JM-310. In this coupled system,ATP generated from S. cerevisiae was provided to E. colifor producing a higher concentration of SAM. The SAMconcentration in the coupled system reached 1.7 g/L. SAMwas purified by a weak acid cationic exchange resin D113,and a simple and economical purification procedure forSAM isolation was achieved. SAM was confirmed byHigh Performance Liquid Chromatography-tandem MassSpectrometry analysis. Our study provides a feasible andconvenient approach to produce SAM.

30. Forage Potential of Proso Millet (Panicum miliaceum L.)

Sheng Nan Wei,Hak Jin Kim,Yan Fen Li,Eun Chan Jeong,Jong Geun Kim 한국초지조사료학회 2020 한국초지조사료학회 학술대회논문집 Vol.2020 No.09

SoC balancing method for energy storage systems in DC microgrids using simplified droop control

Qi, Nan,Fang, Wei,Wang, Wei,Liu, Xiaodong,Liu, Sucheng The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.8

DC microgrids adopt energy storage units to maintain the dynamic power balance between distributed power systems and the load. For DC microgrids in small-scale applications including residential microgrids, to ensure the coordination of the state of charge (SoC) and load current sharing among each of the energy storage units, an improved SoC-balanced control method without interconnection communication is proposed in this paper. The proposed method applies an adaptive droop control expression with a specific SoC-function to regulate its reference voltage in both the charging and discharging processes of the energy storage units. Thus, the balance of the SoC and the load current is achieved autonomously. This method can reduce the bus voltage deviation and weaken the impact of the output current on the bus voltage variation, especially for low-voltage DC microgrids. Moreover, the sampling of the output current is avoided, and both the cost and complexity of controller design are significantly reduced. In addition, a function curves analysis method is proposed to analyze the speed of the SoC balancing and the DC bus voltage deviation, which gives instruction in the choice of the adjustment factor in the adaptive droop equation. A mathematical description of the operating process and a small signal model of the proposed method are established to evaluate the system feasibility and stability. A laboratory-scale DC microgrid is built to verify the proposed method. Finally, simulation and experimental results are presented.

29. Effects of Formic Acid and Lactic Acid Bacteria Additives on Different Species of Silage

Sheng Nan Wei,Hak Jin Kim,Guo Qiang Zhao,Chang Liu,Yan Fen Li,Eun Chan Jeong,Jong Geun Kim 한국초지조사료학회 2020 한국초지조사료학회 학술대회논문집 Vol.2020 No.09

Effects of formic acid and lactic acid bacteria inoculant on main summer crop silages in Korea

( Sheng Nan Wei ),( Yan Fen Li ),( Eun Chan Jeong ),( Hak Jin Kim ),( Jong Geun Kim ) 한국축산학회(구 한국동물자원과학회) 2021 한국축산학회지 Vol.63 No.1

To improve the fermentation quality of silage and reduce the nutrients loss of raw materials during the ensiling process, silage additives are widely used. The effect of additives on silage is also affected by the species of crop. Therefore, this study was designed to explore the effects of formic acid (FA) and lactic acid bacterial inoculant on the quality of main summer crop silage. The experiment was consisted on split-plot design with three replications. The experiment used the main summer forage crops of proso millet (“Geumsilchal”), silage corn (“Gwangpyeongok”), and a sorghum-sudangrass hybrid (“Turbo-gold”). Treatments included silage with Lactic acid bacterial Inoculant (Lactobacillus plantarum [LP], 1.0 × 10⁶ CFU/g fresh matter), with FA (98%, 5 mL/kg), and a control (C, without additive). All silages were stored for 60 days after preparation. All additives significantly increased the crude protein content and in vitro dry matter digestibility (IVDMD) of the silages and also reduced the content of ammonia nitrogen (NH₃-N) and pH. Corn had the highest content of IVDMD, total digestible nutrients and relative feed value among silages. Compared with the control, irrespective of whether FA or LP was added, the water soluble carbohydrate (WSC) of three crops was largely preserved and the WSC content in the proso millet treated with FA was the highest. The treatment of LP significantly increased the lactic acid content of the all silage, while the use of FA significantly increased the content of acetic acid (p < 0.05). The highest count of lactic acid bacteria (LAB) was detected in the LP treatment of corn. In all FA treatment groups, the total microorganism and mold numbers were significantly lower than those of the control and LP groups (p < 0.05). In conclusion, both additives improved the fermentation quality and nutritional composition of the main summer forage crops. The application of FA effectively inhibited the fermentation of the three crops, whereas LAB promoted fermentation. So, both FA and LP can improve the quality of various species of silage.

Evaluation of forage production, feed value, and ensilability of proso millet (Panicum miliaceum L.)

( Sheng Nan Wei ),( Eun Chan Jeong ),( Yan Fen Li ),( Hak Jin Kim ),( Farhad Ahmadi ),( Jong Geun Kim ) 한국축산학회 2022 한국축산학회지 Vol.64 No.1

Whole-plant corn (Zea may L.) and sorghum-sudangrass hybrid [Sorghum bicolor (L.) Moench] are major summer crops that can be fed as direct-cut or silage. Proso millet is a short-season growing crop with distinct agronomic characteristics that can be productive in marginal lands. However, information is limited about the potential production, feed value, and ensilability of proso millet forage. We evaluated proso millet as a silage crop in comparison with conventional silage crops. Proso millet was sown on June 8 and harvested on September 5 at soft-dough stage. Corn and sorghum-sudangrass hybrid were planted on May 10 and harvested on September 10 at the half milk-line and soft-dough stages, respectively. The fermentation was evaluated at 1, 2, 3, 5, 10, 15, 20, 30, and 45 days after ensiling. Although forage yield of proso millet was lower than corn and sorghum-sudangrass hybrid, its relative feed value was greater than sorghum-sudangrass hybrid. Concentrations of dry matter (DM), crude protein, and water-soluble carbohydrate decreased commonly in the ensiling forage crops. The DM loss was greater in proso millet than those in corn and sorghum-sudangrass hybrid. The in vitro dry matter digestibility declined in the forage crops as fermentation progressed. In the early stages of fermentation, pH dropped rapidly, which was stabilized in the later stages. Compared to corn and sorghum-sudangrass hybrid, the concentration of ammonia-nitrogen was greater in proso millet. The count of lactic acid bacteria reached the maximum level on day 10, with the values of 6.96, 7.77, and 6.95 Log₁₀ CFU/g fresh weight for proso millet, corn, and sorghum-sudangrass hybrid, respectively. As ensiling progressed, the concentrations of lactic acid and acetic acid of the three crops increased and lactic acid proportion became higher in the order of sorghum-sudangrass hybrid, corn, and proso millet. Overall, the shorter, fast-growing proso millet comparing with corn and sorghum-sudangrass hybrid makes this forage crop an alternative option, particularly in areas where agricultural inputs are limited. However, additional research is needed to evaluate the efficacy of viable strategies such as chemical additives or microbial inoculants to minimize ammonia-nitrogen formation and DM loss during ensiling.