A heat shock protein 70 protects the green peach aphid (Myzus persicae) against high-temperature stress

Chen Nan,Tan Jia-Yu,Wang Ying,Qi Ming-Hui,Peng Jiang-Nan,Chen De-Xin,Liu Su,Li Mao-Ye 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.4

Heat shock proteins (HSPs) are encoded by Hsp genes and are important in insect tolerance to heat stress. The green peach aphid, Myzus persicae, is an important agricultural pest. The functions of Hsp genes in the thermal tolerance of M. persicae are unknown. This study identified an Hsp70 gene (MpHsp70a) and analyzed its role in protection against high-temperature stress. MpHsp70a encoded a protein consisting of 659 amino acid residues. The protein had three signature motifs of the HSP70 family and was predicted to be localized in the cytoplasm. The highest expression level of MpHsp70a was in adults, and differences in the mRNA levels between apterous and alate adults were not significant. Exposure to high temperatures (30, 35 and 40 ◦ C) for one hour and treatment with 40 ◦ C for different times (0.5, 1 and 2 h) all resulted in a greatly elevated expression level of MpHsp70a, suggesting that the gene is heat-inducible. The transcriptional level of MpHsp70a was suppressed by injection with double-stranded RNA (dsRNA), and knockdown of MpHsp70a significantly increased the suscep tibility of apterous adults to 40 ◦ C. These results indicate that MpHsp70a is required for tolerance to hightemperature stress in M. persicae. Our findings highlight the molecular mechanism underlying Hsp70-mediated thermal adaptation in M. persicae.

Effect of Light with Different Wavelengths on Nostoc flagelliforme Cells in Liquid Culture

( Yu Jie Dai ),( Jing Li ),( Shu Mei Wei ),( Nan Chen ),( Yu Peng Xiao ),( Zhi Lei Tan ),( Shi Ru Jia ),( Nan Nan Yuan ),( Ning Tan ),( Yi Jie Song ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.4

The effects of lights with different wavelengths on the growth and the yield of extracellular polysaccharides of Nostoc flagelliforme cells were investigated in a liquid cultivation. N. flagelliforme cells were cultured for 16 days in 500 ml conical flasks containing BG11 culture medium under 27 μmol·m-2·s-1 of light intensity and 25oC on a rotary shaker (140 rpm). The chlorophyll a, phycocyanin, allophycocyanin, and phycoerythrin contents in N. flagelliforme cells under the lights of different wavelengths were also measured. It was found that the cell biomass and the yield of polysaccharide changed with different wavelengths of light. The biomass and the yield of extracellular polysaccharides under the red or violet light were higher than those under other light colors. Chlorophyll a, phycocyanin, and allophycocyanin are the main pigments in N. flagelliforme cells. The results showed that N. flagelliforme, like other cyanobacteria, has the ability of adjusting the contents and relative ratio of its pigments with the light quality. As a conclusion, N. flagelliforme cells favor red and violet lights and perform the complementary chromatic adaptation ability to acclimate to the changes of the light quality in the environment.

DL-RRT* Algorithm for Least Dose Path Re-planning in Dynamic Radioactive Environments

Nan Chao,Yong-kuo Liu,HONG XIA,Min-jun Peng,Abiodun Ayodeji 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.3

One of the most challenging safety precautions for workers in dynamic, radioactive environments isavoiding radiation sources and sustaining low exposure. This paper presents a sampling-based algorithm,DL-RRT*, for minimum dose walk-path re-planning in radioactive environments, expedient for occupationalworkers in nuclear facilities to avoid unnecessary radiation exposure. The method combines theprinciple of random tree star (RRT*) and D* Lite, and uses the expansion strength of grid search strategyfrom D* Lite to quickly find a high-quality initial path to accelerate convergence rate in RRT*. The algorithminherits probabilistic completeness and asymptotic optimality from RRT* to refine the existingpaths continually by sampling the search-graph obtained from the grid search process. It can not only beapplied to continuous cost spaces, but also make full use of the last planning information to avoid globalre-planning, so as to improve the efficiency of path planning in frequently changing environments. Theeffectiveness and superiority of the proposed method was verified by simulating radiation field undervarying obstacles and radioactive environments, and the results were compared with RRT* algorithmoutput.

p13 from group II baculoviruses is a killing-associated gene

( Nan Lu ),( En Qi Du ),( Yang Kun Liu ),( Hong Qiao ),( Lun Guang Yao ),( Zi Shu Pan ),( Song Ya Lu ),( Yi Peng Qi ) 생화학분자생물학회(구 한국생화학분자생물학회) 2012 BMB Reports Vol.45 No.12

p13 gene was first described in Leucania separata multinuclear polyhedrosis virus (Ls-p13) several years ago, but the function of P13 protein has not been experimentally investigated to date. In this article, we indicated that the expression of p13 from Heliothis armigera single nucleocapsid nucleopolyhedrovirus (Ha-p13) was regulated by both early and late promoter. Luciferase assay demonstrated that the activity of Ha-p13 promoter with hr4 enhancer was more than 100 times in heterologous Sf9 cells than that in nature host Hz-AM1 cells. Both Ls-P13 and Ha-P13 are transmembrane proteins. Confocal microscopic analysis showed that both mainly located in the cytoplasm membrane at 48 h. Results of RNA interference indicated that Ha-p13 was a killing-associated gene for host insects H. armigera. The AcMNPV acquired the mentioned killing activity and markedly accelerate the killing rate when expressing Ls-p13. In conclusion, p13 is a killing associated gene in both homologous and heterologous nucleopolyhedrovirus. [BMB Reports 2012; 45(12): 730-735]

Improved PSO Research for Solving the Inverse Problem of Parabolic Equation

Peng Yamian,Ji Nan,Zhang Huancheng 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.12

Parameter identification problem has important research background and research value, has become in recent years inverse problem of heat conduction of top priority. This paper studies the Parabolic Equation Inverse Problems of parameter identification problem, and applies PSO to solve research. Firstly, this paper establishes the model of the inverse problem of partial differential equations. The content and classification of the inverse problem of partial differential equations are explained. Frequently, the construction and solution of the finite difference method for parabolic equations are studied, and two stable schemes for one dimensional parabolic equation are given. And two numerical simulations were given. Partial differential equation discretization was with difference quotient instead of partial derivative. The partial differential equations with initial boundary value problem into algebraic equations, and then solving the resulting algebraic equations. Then, the basic principles of PSO and its improved algorithms are studied and compared. Particle swarm optimization algorithm program implementation. Finally, the Parabolic Equation Inverse Problems of particle swarm optimization algorithm performed three simulations. We use a set of basis functions gradually approaching the true solution, selection of initial value. The reaction is converted into direct problem question, then use difference method Solution of the direct problem. The solution of the problem with the additional conditions has being compared. The reaction optimization problem is transformed into the final particle swarm optimization algorithm to solve. Verify the Parabolic Equation Inverse Problems of particle swarm optimization algorithm correctness and applicability.

A Procedure for Inducing the Occurrence of Rice Seedling Blast in Paddy Field

Peng Qin,Xiaochun Hu,Nan Jiang,Zhenan Bai,Tiangang Liu,Chenjian Fu,Yongbang Song,Kai Wang,Yuanzhu Yang 한국식물병리학회 2021 Plant Pathology Journal Vol.37 No.2

Rice blast caused by the filamentous fungus Magna- porthe oryzae, is arguably the most devastating rice disease worldwide. Development of a high-throughput and reliable field blast resistance evaluation system is essential for resistant germplasm screening, resistance genes identification and resistant varieties breeding. However, the occurrence of rice blast in paddy field is easily affected by various factors, particularly lack of sufficient inoculum, which always leads to the non- uniform occurrence and reduced disease severity. Here, we described a procedure for adequately inducing the occurrence of rice seedling blast in paddy field, which involves pretreatment of diseased straw, initiation of seedling blast for the first batch of spreader population, inducing the occurrence of the second batch of spreader population and test materials. This procedure enables uniform and consistent infection, which facilitates ef- ficient and accurate assessment of seedling blast resis- tance for diverse rice materials.

Dynamic electromagnetic force variation mechanism and energy loss of a non-contact loading device for a water-lubricated bearing

Nan Wang,Zhe Yuan,Peng Wang 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.6

The current predominant contact loading device has several defects (such as friction, wear, vibration, and noise) which seriously affect the accuracy of test results of waterlubricated bearings. In this study, a non-contact electromagnetic loading device was designed, and the dynamic electromagnetic force variation mechanism and energy loss were examined. First, the structures of the test-rig of a water-lubricated bearing and electromagnetic loading device were described, and mathematical models of the dynamic electromagnetic force, reluctance torque, and energy loss were constructed. Then, finite element analysis was conducted, and the variation rules of magnetic induction intensity, reluctance torque, gap flux density, and energy loss were analyzed. Finally, the test results of numerical calculation and simulation were compared. The dynamic electromagnetic force is revealed to be closely related to the speed and eccentricity of the shaft and the coil current of the electromagnet. Increasing the coil current and shaft speed nonlinearly increases the energy loss of the electromagnetic loading device.

Bandwidth-Related Optimization in High-Speed Frequency Dividers using SiGe Technology

Nan, Chao-Zhou,Yu, Xiao-Peng,Lim, Wei-Meng,Hu, Bo-Yu,Lu, Zheng-Hao,Liu, Yang,Yeo, Kiat-Seng The Institute of Electronics and Information Engin 2012 Journal of semiconductor technology and science Vol.12 No.1

In this paper, the trade-off related to bandwidth of high-speed common-mode logic frequency divider is analyzed in detail. A method to optimize the operating frequency, band-width as well as power consumption is proposed. This method is based on bipolar device characteristics, whereby a negative resistance model can be used to estimate the optimal normalized upper frequency and lower frequency of frequency dividers under different conditions, which is conventionally ignored in literatures. This method provides a simple but efficient procedure in designing high performance frequency dividers for different applications. To verify the proposed method, a static divide-by-2 at millimeter wave ranges is implemented in 180 nm SiGe technology. Measurement results of the divider demonstrate significant improvement in the figure of merit as compared with literatures.

Boron isotopic separation with pyrocatechol-modified resin by chromatography technology: Experiment and numerical simulation

Nan Zhang,Jiafei Lyu,Peng Bai,Xianghai Guo 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.57 No.-

Boron isotopic separation was investigated experimentally and theoretically on boron-specific adsorbent, namely pyrocatechol-modified resin (CL-RESIN). The static adsorption results with initial boron concentration of 8.648 g L−1 at 25 °C were well fitted by the pseudo-second-order kinetic model and Henry isotherm model, from which relevant parameters were used for subsequent isotopic separation simulation by Aspen Chromatograph. The maximum static boron isotopic separation factor with CL-RESIN was 1.13 at 25 °C, thus adsorption-based boron isotopic separation in a chromatographic column packing with CL-RESIN was further studied by experiments and simulations. 11B had greater affinity with CL-RESIN in concentrated boric acid solution with dynamic boron isotopic separation factor of 1.15 and enriched 10B was collected in effluent. Simulation of boron isotopic separation was completed, and simulated results were in good agreement with experimental breakthrough curves under the same conditions. Furthermore, the dynamic behaviors of boron isotopic separation were predicted by simulation under different operating conditions. Response surface methodology (RSM) was employed to determine optimized operating conditions in a chromatographic column. Consequently, the optimized operating conditions were achieved with flow rate of 1.24 mL min−1, 44 cm column length, 0.46 cm column diameter and feed concentration of 8.648 g L−1.

Hepatitis B Virus Infection Is Associated with Poor Prognosis in Patients with Advanced Non Small Cell Lung Cancer

Peng, Jie-Wen,Liu, Dong-Ying,Lin, Gui-Nan,Xiao, Jian-jun,Xia, Zhong-Jun Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.13

Background: Hepatitis B virus (HBV) infection has been reported to be associated with inferior prognosis in hepatocellular and pancreatic carcinoma cases, but has not been studied with respect to non small cell lung cancer (NSCLC). The purpose of this study was to investigate the prognostic significance of HBV infection in advanced NSCLC patients. Materials and Methods: A retrospective cohort of 445 advanced NSCLC patients was recruited at our hospital from January 1, 2003 until August 30, 2014. Serum HBV markers were tested by enzyme-linked immunosorbent assay. COX proportional hazards analysis was used to evaluate associations of HBV infection with overall survival (OS). Results: Of 445 patients who were qualified for the study, 68 patients were positive for HBsAg, also considered as HBV infection. Patients in HBsAg negative group were found to have better OS (12.6 months [12.2-12.9]) than those in HBsAg positive group (11.30 months [10.8-11.9]; p=0.001). Furthermore, COX multivariate analysis identified HBV infection as an independent prognostic factor for OS (HR 0.740 [0.560, 0.978], p=0.034). Conclusions: Our study found that HBsAg-positive status was an independent prognostic factor for OS in patients with advanced NSCLC. Future prospective studies are required to confirm our findings.