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1

Investigation of low-sidelobe beampattern controlling methods for acoustic transmitting array of underwater vehicles

100%
He Z., Shi Q., Wu S.
Polish Maritime Research
|
2017
|
tom 24
|
nr Special Issue S2
In underwater unmanned vehicles, complex acoustic transducer arrays are always used to transmitting sound waves to detect and position underwater targets. Two methods of obtaining low-sidelobe transmitting beampatterns for acoustic transmitting arrays of underwater vehicles are investigated. The first method is the boundary element model optimization method which used the boundary element theory together with the optimization method to calculate the driving voltage weighting vector of the array. The second method is the measured receiving array manifold vector optimization method which used the measured receiving array manifold vectors and optimization method to calculate the weighting vector. Both methods can take into account the baffle effect and mutual interactions among elements of complex acoustic arrays. Computer simulation together with experiments are carried out for typical complex arrays. The results agree well and show that the two methods are both able to obtain a lower sidelobe transmitting beampattern than the conventional beamforming method, and the source level for each transmitting beam is maximized in constraint of the maximum driving voltage of array elements being constant. The effect of the second method performs even better than that of the first method, which is more suitable for practical application. The methods are very useful for the improvement of detecting and positioning capability of underwater unmanned vehicles
2

Naringin induces endoplasmic reticulum stress-mediated apoptosis, inhibits β-catenin pathway and arrests cell cycle in cervical cancer cells

88%
Lin R., Hu X., Chen S., Shi Q., Chen H.
Acta Biochimica Polonica
|
2020
|
tom 67
|
nr 2
3
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Sexual dimorphism in perissodactyl rhinocerotid Chilotherium wimani from the Late Miocene of the Linxia Basin (Gansu, China)

88%
Chen S., Deng T., Hou S., Shi Q., Pang L.
Acta Palaeontologica Polonica
|
2010
|
tom 55
|
nr 4
Sexual dimorphism is reviewed and described in adult skulls of Chilotherium wimani from the Linxia Basin. Via the analysis and comparison, several very significant sexually dimorphic features are recognized. Tusks (i2), symphysis and occipital surface are larger in males. Sexual dimorphism in the mandible is significant. The anterior mandibular morphology is more sexually dimorphic than the posterior part. The most clearly dimorphic character is i2 length, and this is consistent with intrasexual competition where males invest large amounts of energy jousting with each other. The molar length, the height and the area of the occipital surface are correlated with body mass, and body mass sexual dimorphism is compared. Society behavior and paleoecology of C. wimani are different from most extinct or extant rhinos. M/F ratio indicates that the mortality of young males is higher than females. According to the suite of dimorphic features of the skull of C. wimani, the tentative sex discriminant functions are set up in order to identify the gender of the skulls.
4

DNA microarray gene expression profile of Mycobacterium tuberculosis when exposed to osthole

76%
Wei J., Guo N., Liang J., Yuan P., Shi Q., Tang X., Yu L.
Polish Journal of Microbiology
|
2013
|
tom 62
|
nr 1
Tuberculosis (TB), affecting one-third of the global population, kills an estimated two to three million people every year. The development of drug resistance is becoming a serious threat to any attempt to control this disease, which underscores the need for new agents targeting Mycobacterium tuberculosis (M. tuberculosis). Osthole (7-methoxy-8-isopentenoxycoumarin) is a coumarin derivative present in many medicinal plants. Previous studies have shown that osthole possesses antimycobacterial effects, however, the action mechanism of osthole is unclear. In the study, we used a commercial oligonucleotide microarray to determine the overall transcriptional response of M.tuberculosis H37Rv triggered by exposure to osthole. Analysis of the microarray data revealed that a total of 478 genes were differentially regulated by osthole. Of these, 241 genes were upregulated, and 237 genes were downregulated. Some of the important genes that were significantly regulated are related to different pathways such as fumarate reductase, class I peroxidase, cell wall, nitrate respiration, and protein synthesis. Real-time quantitative RT-PCR was performed for chosen genes to validate the microarray results. To our knowledge, this genome-wide transcriptomics approach has produced the first insights into the response of M. tuberculosis when exposed to osthole.
5

Characterization of a maize ERF gene, ZmERF1, in hormone and stress responses

76%
Shi Q., Dong Y., Zhou Q., Qiao D., Ma Z., Zhang L., Li Y.
Acta Physiologiae Plantarum
|
2016
|
tom 38
|
nr 05
6

HIF-1α promotes the migration and invasion of hepatocellular carcinoma cells via the IL-8–NF-κB axis

76%
Feng W., Xue T., Huang S., Shi Q., Tang C., Cui G., Guo H.
Cellular and Molecular Biology Letters
|
2018
|
tom 23
Background: Hypoxia plays a critical role in many cancers. Hypoxia inducible factor-1α (HIF-1α) is an important mediator of the hypoxia response. It regulates the expression of various chemokines involved in tumor growth, angiogenesis and metastasis but the associated pathway needs further investigation. Methods: The expression level of HIF-1α was determined in hepatocellular carcinoma (HCC) cells. The correlation of interleukin-8 (IL-8) and HIF-1α was assessed by knocking down HIF-1α. These cells were also used to assess its influence on HCC cell migration and invasion was checked. Pyrrolidinedithiocarbamate (PDTC), an inhibitor of NF-κB, was used to confirm the associated signaling pathway. Results: HIF-1α was significantly expressed in HCC cells and found to promote HCC cell migration and invasion in an IL-8-dependent manner. NF-κB was confirmed to be involved in the process. Conclusions: HIF-1α promotes HCC cell migration and invasion by modulating IL-8 via the NF-κB pathway.
7

Normal spermatogenesis and fertility in Ddi1 (DNA damage inducible 1) mutant mice

76%
Yousaf A., Wu Y., Khan R., Shah W., Khan I., Shi Q., Jiang X.
Reproductive Biology
|
2020
|
tom 20
|
nr 4
8

Transcriptome analysis of alternative splicing in different moso bamboo tissues

64%
Li L., Shi Q., Hou D., Cheng Z., Li J., Ma Y., Li X., Mu S., Gao J.
Acta Physiologiae Plantarum
|
2018
|
tom 40
|
nr 05
9

Comaparative effects of NaCl and NaHCO3 stresses on respiratory metabolism, antioxidant system, nutritional status, and oragnic acid metabolism in tomato roots

64%
Gong B., Wen D., Bloszies S., Li X., Wei M., Yang F., Shi Q., Wang X.
Acta Physiologiae Plantarum
|
2014
|
tom 36
|
nr 08
Physiological responses of tomato roots to NaCl and NaHCO₃ stresses were investigated in a hydroponic setting. The relative growth rate of tomato plants was significantly reduced in both NaCl and NaHCO₃ treatments, especially under NaHCO₃ stress. Tomato root respiration increased under low concentrations of NaCl and NaHCO₃ stresses. However, high concentrations of both NaCl and NaHCO₃ significantly inhibited respiration, especially in the NaHCO₃ treatment. With increasing concentration of NaCl and NaHCO₃ treatment, root Na accumulation increased, while accumulation of N, P, K, Fe, and Mg was significantly lower. Compared to NaCl, NaHCO₃ treatment resulted in more dramatic changes in these nutrients. All organic acids investigated were increased by NaHCO₃ after 5 days of treatment, but only oxalate, tartrate and malate were induced by NaCl. This implies that global regulation of organic acids might play an important role in tomato’s alkali stress tolerance. Compared to NaCl treatments, NaHCO₃ treatments induced much higher levels of reactive oxygen species (ROS) and lipid peroxidation after 5 days of treatment, which was accompanied by higher activities of antioxidant enzymes and higher concentrations of ascorbate–glutathione. However, after 10 days of treatment, 100 mM NaHCO₃ stress led to lower accumulation of ROS, antioxidant enzyme activities, and ascorbate–glutathione content. This may have been because root metabolism had almost completely stopped, as indicated by lower root respiration and activity.
10

Salix matsudana Koidz tolerance mechanisms to cadmium: uptake and accumulation, subcellular distribution, and chemical forms

64%
Wu H., Wang J., Li B., Ou Y., Wang J., Shi Q., Jiang W., Liu D., Zou J.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 4
Salix matsudana roots exposed to 10, 50, and 100 μM Cd solutions for 24 h were carried out in order to understand the mechanisms involved in Cd tolerance and detoxification. 50 and 100 μM Cd inhibited root length significantly (P < 0.05). Cd levels in roots increased significantly with increasing Cd concentrations, and the contents of Fe, Mn, Zn, and Ca decreased significantly. A Cd-specific Leadmium Green AM dye probe showed that the meristem zone was the absorption and accumulation site of Cd in the roots. Subcellular fractionation of Cd-containing tissues indicated that about 53% of the Cd was accumulated in the cell wall of S. matsudana roots at 10 μM Cd and 65% of the Cd at 100 μM Cd, indicating that Cd binding and/or precipitation in the cell wall in roots may serve as the first barrier to reduce the cytosolic-free Cd ions. The proportion of CdE and Cdw in roots is low when compared with the other Cd chemical forms. CdHCl, Cdr, and CdHAc represent 46% (10 μM Cd), 49% (50 μM Cd), and 59% (100 μM Cd) of total Cd, and CdNaCl represents 42% (10 μM Cd), 44% (50 μM Cd), and 32% (100 μM Cd).
11

Cd subcellular localization in root tips of Hordeum vulgare

64%
Shi Q., Wang J., Zou J., Jiang Z., Wang J., Wu H., Jiang W., Liu D.
Polish Journal of Environmental Studies
|
2016
|
tom 25
|
nr 2
The effects of Cd on the subcellular localization in root tip cells of Hordeum vulgare were investigated by Energy dispersive x-ray analysis (EDXA) in order to further understand Cd toxic mechanisms in plants. EDXA showed that Cd ions were localized in meristem, elongation, and mature zone in the root tips. In transverse section of the mature zone, Cd was accumulated in epidermal, cortical, and vessel cells, and the level of Cd is in the order: epidermal cells < vessel cells < cortical cells. In cortical cells Cd ions were observed in cytoplasm and walls.
12

Caffeic acid protects cucumber against chilling stress by regulating antioxidant enzyme activity and proline and soluble sugar contents

64%
Wan Y.-Y., Zhang Y., Zhang L., Zhou Z.-Q., Li Y., Shi Q., Wang X.-J., Bai J.-G.
Acta Physiologiae Plantarum
|
2015
|
tom 37
|
nr 01
To investigate the physiological mechanism underlying chilling stress mitigation by exogenous caffeic acid (CA), we pretreated Cucumis sativus cv. Jinchun no. 4 seedlings with CA for 2 days, followed by exposure to normal (25/18 C) or cold (15/8 C) temperatures for 1 day.We chose 25 lM as the optimum CA concentration, since it produced lower levels of superoxide anion radical, hydrogen peroxide and malondialdehyde in chilling-stressed leaves than other concentrations of CA. Chilling treatment caused 50 % of the second leaves be withered, reduced the relative water content in the leaves and inhibited plant growth. Pretreatment with 25 lMCA alleviated the damaging effects of chilling. When the CA-pretreated seedlings were exposed to chilling, the superoxide dismutase, guaiacol peroxidase, catalase glutathione peroxidase, monodehydroascorbate reductase, ascorbate peroxidase, glutathione reductase and dehydroascorbate reductase activities were higher than those produced by chilling treatment alone, which coincided with increased transcript levels of copper/zinc superoxide dismutase, glutathione peroxidase and manganese superoxide dismutase genes; these results are consistent with the increased contents of ascorbate and glutathione. The application of 25 lM CA also increased the contents of endogenous CA and ferulic acid, as well as proline and soluble sugars, in chilling-stressed leaves. Therefore, exogenous CA treatment increases endogenous CA levels, induces antioxidant enzyme activity and reduces the levels of reactive oxygen species under chilling stress, thus protecting cucumber from chilling stress. Soluble sugars and proline are involved in the CA-mitigated chilling stress response.
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