A phase synthesis time reversal impact imaging method for on-line composite structure monitoring

Lei Qiu,Shenfang Yuan 국제구조공학회 2011 Smart Structures and Systems, An International Jou Vol.8 No.3

Comparing to active damage monitoring, impact localization on composite by using time reversal focusing method has several difficulties. First, the transfer function of the actuator-sensor path is difficult to be obtained because of the limitation that no impact experiment is permitted to perform on the real structure and the difficulty to model it because the performance of real aircraft composite is much more complicated comparing to metal structure. Second, the position of impact is unknown and can not be controlled as the excitation signal used in the active monitoring. This makes it not applicable to compare the difference between the excitation and the focused signal. Another difficulty is that impact signal is frequency broadband, giving rise to the difficulty to process virtual synthesis because of the highly dispersion nature of frequency broadband Lamb wave in plate-like structure. Aiming at developing a practical method for on-line localization of impact on aircraft composite structure which can take advantage of time reversal focusing and does not rely on the transfer function, a PZT sensor array based phase synthesis time reversal impact imaging method is proposed. The complex Shannon wavelet transform is presented to extract the frequency narrow-band signals from the impact responded signals of PZT sensors. A phase synthesis process of the frequency narrow-band signals is implemented to search the time reversal focusing position on the structure which represents the impact position. Evaluation experiments on a carbon fiber composite structure show that the proposed method realizes the impact imaging and localization with an error less than 1.5 cm. Discussion of the influence of velocity errors and measurement noise is also given in detail.

Complete Genome Sequence of Salmonella enterica Serovar Pullorum Multidrug Resistance Strain S06004 from China(s)

( Qiu Chun Li ),( Ya Chen Hu ),( Yin Fei Wu ),( Xiao Chun Wang ),( Xiao Lei Xie ),( Ming Xin Tao ),( Jun Lei Yin ),( Zhi Jie Lin ),( Yang Jiao ),( Li Juan Xu ),( Xinan Jiao ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.5

As Salmonella enterica serovar Pullorum remains a major economic problem for the poultry industries of countries with no efficient control measures, we presented a multidrug resistance strain S06004 (isolated from a clinically sick chicken in China in 2006) for genome sequencing. The genome comparison showed that the strain contained two prophages, the ST104 and prophage-4 (Fels2) of E. coli LF82, which were not detected in the only published genomes of S. Pullorum RKS5078 and CDC1983-67. In addition, the GyrA Ser83 point mutation, drugresistant genes, and many antibiotic pump systems that are present in S06004 may be contributing to the multidrug resistance of this strain.

A phase synthesis time reversal impact imaging method for on-line composite structure monitoring

Qiu, Lei,Yuan, Shenfang Techno-Press 2011 Smart Structures and Systems, An International Jou Vol.8 No.3

Comparing to active damage monitoring, impact localization on composite by using time reversal focusing method has several difficulties. First, the transfer function of the actuator-sensor path is difficult to be obtained because of the limitation that no impact experiment is permitted to perform on the real structure and the difficulty to model it because the performance of real aircraft composite is much more complicated comparing to metal structure. Second, the position of impact is unknown and can not be controlled as the excitation signal used in the active monitoring. This makes it not applicable to compare the difference between the excitation and the focused signal. Another difficulty is that impact signal is frequency broadband, giving rise to the difficulty to process virtual synthesis because of the highly dispersion nature of frequency broadband Lamb wave in plate-like structure. Aiming at developing a practical method for on-line localization of impact on aircraft composite structure which can take advantage of time reversal focusing and does not rely on the transfer function, a PZT sensor array based phase synthesis time reversal impact imaging method is proposed. The complex Shannon wavelet transform is presented to extract the frequency narrow-band signals from the impact responded signals of PZT sensors. A phase synthesis process of the frequency narrow-band signals is implemented to search the time reversal focusing position on the structure which represents the impact position. Evaluation experiments on a carbon fiber composite structure show that the proposed method realizes the impact imaging and localization with an error less than 1.5 cm. Discussion of the influence of velocity errors and measurement noise is also given in detail.

Age-stage, two-sex life tables of the maple poison moth (Lymantria nebulosa Wileman) at different ambient temperatures

Lei Ling,Huang Hui Jing,Yi Jin Yu,Qiu Lin,Ding Wen Bin,He Hua Liang,Yi Tu Yong,Li You Zhi,Xue Jin 한국곤충학회 2021 Entomological Research Vol.51 No.4

The maple poison moth (MPM), Lymantria nebulosa (Wileman), is a Lepidopteran defoliator and one of the most important pests of Liquidambar formosana Hance. The objective of this study was to determine the effects of temperature on the population growth and reproduction of this species. MPM were raised in artificial climate chambers in a laboratory at 21 ± 1°C, 24 ± 1°C, 27 ± 1°C, 30 ± 1°C, 33 ± 1°C and 36 ± 1°C, under a relative humidity (RH) of 70% ± 10% and a 14 L:10D photoperiod, and age-stage, two-sex life tables complied for insects at each temperature. The developmental duration, adult preoviposition period and overall preoviposition period decreased with temperature in a time-dependent manner. The growth curves of the different temperature groups overlapped considerably. The highest larval survival rate (80%) was recorded at 30 ± 1°C. At 36°C only a few eggs hatched and the first instar could not complete the first molt. We consequently regard 36°C as the lethal temperature threshold for this species. Life expectancy decreased with age under all six temperatures. The endogenous growth rate was significantly lower at 21 ± 1°C than at the other temperatures, and was highest in 30 ± 1°C group. The net growth rate of the 30 ± 1°C group was also significantly higher than others. Reproductive parameters were highest at 27 ± 1°C and 30 ± 1°C. Although environmental factors absent from the laboratory environment may limit the generality of our results, they nonetheless provide a theoretical basis for developing integrated control methods for MPM in the wild.

Effects of Salinity and Curing Time on Compression Behavior of Fly Ash Stabilized Marine Clay

Lei Pan,Hao Liu,Wenjie Qiu,Jie Yin 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.10

This study involves an experimental examination of compression behaviors of fly ash stabilized marine clay cured at different times concerning the influences of pore water salinity. A set of laboratory one-dimensional compression tests was conducted on soft Lianyungang marine clay specimens with various pore water salinities and stabilized with fly ash. Test results indicated that both salinity and curing time influenced the compression characteristic of fly ash stabilized clay. The presence of fly ash obviously reduced the compressibility of the untreated marine clay sample. The semi-logarithmic compression curve of untreated pure soil was a straight line, whereas fly ash stabilized clay samples exhibited the pattern of two straight lines. All the fly ash stabilized soil specimens were well represented by two straight lines in the bilogarithmic coordinate, making it convenient to determine the compression yield stress. The compression index at the pre-yield stage was not susceptible to the variation in the salinity and curing period, whereas at the post-yield stage it exhibited a downward tendency as salinity and curing time increased. The value of yield stress for stabilized marine clay specimen exhibited a downward tendency with increasing salinity, whereas it increased significantly within 7 days and tended to level off with the elapsed curing time. The adverse effect of salinity and the positive influence of curing time on yield stress should be considered in engineering applications.

Modeling and Analysis of Load-Balancing Based on Base-Station CoMP with Guaranteed QoS

( Lei Feng ),( Wenjing Li ),( Mengjun Yin ),( Xuesong Qiu ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.9

With the explosive deployment of the wireless communications technology, the increased QoS requirement has sparked keen interest in network planning and optimization. As the major players in wireless network optimization, the BS`s resource utilization and mobile user`s QoS can be improved a lot by the load-balancing technology. In this paper, we propose a load-balancing strategy that uses Coordinated Multiple Points (CoMP) technology among the Base Stations (BS) to effectively extend network coverage and increase edge users signal quality. To use universally, different patterns of load-balancing based on CoMP are modeled and discussed. We define two QoS metrics to be guaranteed during CoMP load balancing: call blocking rate and efficient throughput. The closed-form expressions for these two QoS metrics are derived. The load-balancing capacity and QoS performances with different CoMP patterns are evaluated and analyzed in low-dense and high-dense traffic system. The numerical results present the reasonable CoMP load balancing pattern choice with guaranteed QoS in each system.

Valsartan regulates TGF-b/Smads and TGF-b/p38 pathways through lncRNA CHRF to improve doxorubicin-induced heart failure

Lei Chen,Kui-Po Yan,Xin-Can Liu,Wei Wang,Chao Li,Ming Li,Chun-Guang Qiu 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.1

This study investigated the interaction amongvalsartan (VAL), TGF-b pathways, and long non-codingRNA (lncRNA) cardiac hypertrophy-related factor (CHRF)in doxorubicin (DOX)-induced heart failure (HF), andexplored their roles in DOX-induced HF progression. HFmice models in vivo were constructed by DOX induction. The expression of CHRF and TGF-b1 in hearts wasdetected, along with cardiac function, caspase-3 activity,and cell apoptosis. Primary myocardial cells were pretreatedwith VAL, followed by DOX induction in vitro forfunctional studies, including the detection of cell apoptosiswith terminal deoxynucleotidyl transferase dUTP nick-endlabeling and the expression of proteins associated withTGF-b1 pathways. HF models were established in vivo andin vitro. Expression of CHRF and TGF-b1 was up-regulated,and cell apoptosis and caspase-3 activity wereincreased in the hearts and cells of the HF models. VALsupplementation alleviated the cardiac dysfunction andinjury in the HF process. Moreover, overexpressed CHRFup-regulated TGF-b1, promoted myocardial cell apoptosis,and reversed VAL’s cardiac protective effect, while interferenceof CHRF (si-CHRF) did the opposite. Down-regulationof CHRF reversed the increased expression of TGFb1and the downstream proteins induced by pcDNA-TGFb1in HL-1 cells, while overexpression of CHRF reversedthe VAL’s cardiac protective effect in vivo. In conclusion,VAL regulates TGF-b pathways through lncRNA CHRF toimprove DOX-induced HF.

ATM Signaling Pathway Is Implicated in the SMYD3-mediated Proliferation and Migration of Gastric Cancer Cells

Lei Wang,Qiu-Tong Wang,Yu-Peng Liu,Qing-Qing Dong,Hai-Jie Hu,Zhi Miao,Shuang Li,Yong Liu,Hao Zhou,Tong-Cun Zhang,Wen-Jian Ma,Xuegang Luo 대한위암학회 2017 Journal of gastric cancer Vol.17 No.4

Purpose: We previously found that the histone methyltransferase suppressor of variegation, enhancer of zeste, trithorax and myeloid-nervy-deformed epidermal autoregulatory factor-1 domain-containing protein 3 (SMYD3) is a potential independent predictive factor or prognostic factor for overall survival in gastric cancer patients, but its roles seem to differ from those in other cancers. Therefore, in this study, the detailed functions of SMYD3 in cell proliferation and migration in gastric cancer were examined. Materials and Methods: SMYD3 was overexpressed or suppressed by transfection with an expression plasmid or siRNA, and a wound healing migration assay and Transwell assay were performed to detect the migration and invasion ability of gastric cancer cells. Additionally, an MTT assay and clonogenic assay were performed to evaluate cell proliferation, and a cell cycle analysis was performed by propidium iodide staining. Furthermore, the expression of genes implicated in the ataxia telangiectasia mutated (ATM) pathway and proteins involved in cell cycle regulation were detected by polymerase chain reaction and western blot analyses. Results: Compared with control cells, gastric cancer cells transfected with si-SMYD3 showed lower migration and invasion abilities (P<0.05), and the absence of SMYD3 halted cells in G2/M phase and activated the ATM pathway. Furthermore, the opposite patterns were observed when SMYD3 was elevated in normal gastric cells. Conclusions: To the best of our knowledge, this study provides the first evidence that the absence of SMYD3 could inhibit the migration, invasion, and proliferation of gastric cancer cells and halt cells in G2/M phase via the ATM-CHK2/p53-Cdc25C pathway. These findings indicated that SMYD3 plays crucial roles in the proliferation, migration, and invasion of gastric cancer cells and may be a useful therapeutic target in human gastric carcinomas.

Synthesis, Structure and Biological Properties of a Novel Copper (II) Supramolecular Compound Based on 1,2,4-Triazoles Derivatives

Qiu, Guang-Mei,Wang, Cui-Juan,Zhang, Ya-Jun,Huang, Shuai,Liu, Xiao-Lei,Zhang, Bing-Jun,Zhou, Xian-Li Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.8

A novel mononuclear supramolecule of copper(II) has been synthesized with Ippyt ligand (Ippyt=3-(4'-imidazole phenyl)-5-(pyrid-2''-yl)-1,2,4-triazole) (1). Compound 1, namely [$Cu(Ippyt)_2(H_2O)_2$], has been characterized by single-crystal X-ray diffraction, IR spectrum, elemental analysis and thermogravimetric analysis. Structure determination reveals that the elongated-octahedral geometry is formed in the vicinity of the copper (II) atom being coordinated by four nitrogen atoms from two Ippyt ligands occupying the equatorial position and two oxygen atoms from two coordinated water molecules in the axial position, which together form the $N_4O_2$ donor set. Hydrogen bonding interactions between nitrogen and oxygen atoms result in the set up of a supramolecular network architecture. Biological properties including antibacterial activity and superoxide dismutase (SOD) mimetic activity of compound 1 have been investigated by agar diffusion method and the modified Marklund method, respectively. The results indicate that compound 1 exhibits a stronger antibacterial efficiency than the parent ligand and it also has a certain radical-scavenging activity.

Loss of Expression of PTEN is Associated with Worse Prognosis in Patients with Cancer

Qiu, Zhi-Xin,Zhao, Shuang,Li, Lei,Li, Wei-Min Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.11

Background: The tumor suppressor phosphatase and tensin homolog (PTEN) is an important negative regulator of cell-survival signaling. However, available results for the prognostic value of PTEN expression in patients with cancer remain controversial. Therefore, a meta-analysis of published studies investigating this issue was performed. Materials and Methods: A literature search via PubMed and EMBASE databases was conducted. Statistical analysis was performed by using the STATA 12.0 (STATA Corp., College, TX). Data from eligible studies were extracted and included into the meta-analysis using a random effects model. Results: A total of 3,810 patients from 27 studies were included in the meta-analysis, 22 investigating the relationship between PTEN expression and overall survival (OS) using univariate analysis, and nine with multivariate analysis. The pooled hazard ratio (HR) for OS was 1.64 (95% confidence interval (CI): 1.32-2.05) by univariate analysis and 1.56 (95% CI: 1.20-2.03) by multivariate analysis. In addition, eight papers including two disease-free-survival analyses (DFSs), four relapse-free-survival analyses (RFSs), three progression-free-survival analyses (PFSs) and one metastasis-free-survival analysis (MFS) reported the effect of PTEN on survival. The results showed that loss of PTEN expression was significant correlated with poor prognosis, with a combined HR of 1.74 (95% CI: 1.24-2.44). Furthermore, in the stratified analysis by the year of publication, ethnicity, cancer type, method, cut-off value, median follow-up time and neoadjuvant therapy in which the study was conducted, we found that the ethnicity, cancer type, method, median follow-up time and neoadjuvant therapy are associated with prognosis. Conclusions: Our study shows that negative or loss of expression of PTEN is associated with worse prognosis in patients with cancer. However, adequately designed prospective studies need to be performed for confirmation.