10 results on '"Li, Zhenkai"'
Search Results
2. LncRNA-ENST00000556926 regulates the proliferation, apoptosis and mRNA transcriptome of malignant-transformed BEAS-2B cells induced by coal tar pitch
- Author
-
Zhu, Yonghang, Li, Zhongqiu, Wang, Weiguang, Jing, Linhao, Yu, Qi, Li, Zhenkai, Chen, Xu, Zhang, Jiatong, Zhang, Peng, Feng, Feifei, and Zhang, Qiao
- Abstract
As a byproduct of coal tar distillation, coal tar pitch (CTP) has been proven to be carcinogenic to human. However, the mechanisms of lung cancer induced by CTP are still unclear. It has been shown that long non-coding RNAs (LncRNAs) play an important role in the development of human cancers. This study aims to investigate the effect of LncRNA-ENST00000556926 on malignant-transformed human bronchial epithelial (BAES-2B) cells induced by coal tar pitch extracts (CTPE). In this study, BEAS-2B cells were treated with 2.4 μg/ml of CTPE for 72 h and then passaged; and the cells were treated 4 times in the same procedure, then passaged until passage 30 (CTPE30). Cell counting kit-8 (CCK-8) assay was used to detect cell viability, then cell cycle and apoptosis were analyzed by flow cytometry, and transcriptome sequencing analysis was used to detect differentially expressed mRNAs after interference of ENST00000556926. The results indicated that the expression of ENST00000556926 in CTPE30 group was significantly higher compared with control group. Furthermore, after interfering the expression of ENST00000556926, cell viability was inhibited, and cell cycle was arrested while apoptosis of malignant-transformed BEAS-2B cells was promoted. Moreover, a total of 159 differentially expressed mRNAs were screened out after interference of ENST00000556926, including 62 up-regulated mRNAs and 97 down-regulated mRNAs. In addition, knockdown of ENST00000556926 decreased the expression of thioredoxin domain containing 5 (TXNDC5) and FOXD1. In conclusion, LncRNA-ENST00000556926 could regulate the proliferation, apoptosis and mRNA transcriptome of malignant-transformed BEAS-2B cells induced by CTP, which may provide a novel treatment strategy for lung cancer.Graphical Abstract
- Published
- 2021
- Full Text
- View/download PDF
3. Circularly polarized terahertz wave independently controlled tunable spin-decoupled metasurface.
- Author
-
Zhang, Yuping, Jiang, Chunyang, Li, Zhenkai, Sang, Xiaotong, Wang, Jian, Sun, Xiangzhe, Zhao, Shengjie, Lu, Bo, Liu, Meng, and Zhang, Huiyun
- Abstract
• Function switching under the same incident condition. • Function switching under different incident conditions. • The topological charge 1 to 2 of the vortex beam is switched. • Achieve bands in the terahertz range. The research and development of multifunctional metasurfaces has attracted much attention, and manipulating multifunctional devices with greater degrees of freedom is a continuing trend. In this study, we propose a tunable multifunctional metasurface with terahertz (THz) frequency and demonstrate it theoretically. By introducing the propagation phase decoupling conjugate response, we realize the independent control of beam deflection(deflection angle is 8.1°), beam splitting(split angle is 16.5°), and vortex beam mode switching under different incident conditions. At the same time, by changing the Fermi level of the Dirac semimetal, the switching between different states under the same incident condition is realized. The results of this study are expected to contribute to promising applications in future for improving the capacity of THz communication systems, independently regulating multi-functional devices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. Perfect narrowband circular dichroism based on intrinsic chiral dual quasi-bound states in the continuum in terahertz metasurfaces.
- Author
-
Zhang, Huiyun, Wang, Kun, Li, Zhenkai, Ma, Huifang, Liu, Meng, and Zhang, Yuping
- Abstract
• The degeneracy of the two quasi-BICs provides selectivity for different bandwidth transmission of circularly polarized waves. • Both BICs of the structure exhibit CD at the same time. • The free choice of mode eigenstate is realized. • In the study of narrowband chirality, the Q-factor reaches 6822 and the CD reaches 0.99. Circular dichroism (CD) of chiral structures has wide applications in ultra-sensitive biosensing, wavefront manipulation, and other fields. However, 3D chiral structures require a complex fabrication process, and 2D non-intrinsic chiral structures are difficult to achieve narrow-band perfect CD. Here we proposed a tilted cylindrical structure of a terahertz intrinsic chiral metasurface. Through energy band calculation, topological analysis, multipole decomposition and other research methods, we have realized the separation and merging of topological charges, the degeneracy of modes with opposite polarizations, the free selection of mode eigenstates, and the perfect CD with ultra-high quality (Q) factor. In the study of narrowband chirality, the Q -factor reaches 6822 and the CD reaches 0.99. In addition, both bound states in the continuum (BICs) of the structure exhibit CD at the same time, with Q -factors of 862 and 2673 and CD of –0.98 and 0.98 for the two BICs, respectively. Our work provides new solutions for the study of terahertz narrowband chirality and spin-selective asymmetric transport. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
5. The relationship between endoplasmic reticulum stress and autophagy in apoptosis of BEAS-2B cells induced by cigarette smoke condensate
- Author
-
Yu, Qi, Yang, Sa, Li, Zhongqiu, Zhu, Yonghang, Li, Zhenkai, Zhang, Jiatong, Li, Chunyang, Feng, Feifei, Wang, Wei, and Zhang, Qiao
- Abstract
Cigarette smoke (CS) is one of the severe risk factors for the development of the pulmonary disease. However, the underlying mechanisms, especially the CS-induced the human bronchial epithelial cells (BEAS-2B) apoptosis related to endoplasmic reticulum stress (ERS) and autophagy, remains to be studied. This study aims to investigate the relationship between ERS and autophagy in apoptosis induced by CS condensate (CSC). BEAS-2B cells were stimulated with 0.02, 0.04 and 0.08 mg/ml CSC for 24 h to detect the ERS, autophagy and apoptosis. Then, ERS and autophagy of BEAS-2B cells were inhibited, respectively, by using 4-PBA and 3-MA, and followed by CSC treatment. The results showed that CSC decreased cell viability, increased cell apoptosis, elevated cleaved-caspase 3/pro-caspase 3 ratio and Bax expressions, but decreased Bcl-2 expressions. The GRP78 and CHOP expressions and LC3-II/LC3-I ratio were dose-dependently increased. The structure of the endoplasmic reticulum was abnormal and the number of autolysosomes was increased in BEAS-2B cells after CSC stimulation. The LC3-II/LC3-I ratio was decreased after ERS inhibition with 4-PBA, but GRP78 and CHOP expressions were enhanced after autophagy inhibition with 3-MA. CSC-induced apoptosis was further increased, Bax expressions and cleaved-caspase 3/pro-caspase 3 ratio were improved, but Bcl-2 expressions were decreased after 3-MA or 4-PBA treatment. In conclusion, the study indicates that ERS may repress apoptosis of BEAS-2B cells induced by CSC via activating autophagy, but autophagy relieves ERS in a negative feedback. This study provides better understanding and experimental support on the underlying mechanisms of pulmonary disease stimulated by CS.
- Published
- 2021
- Full Text
- View/download PDF
6. A review on high temperature resistant polyimide films: Heterocyclic structures and nanocomposites
- Author
-
Ma, Pengchang, Dai, Chuntao, Wang, Huaizhen, Li, Zhenkai, Liu, Hongbo, Li, Weimin, and Yang, Chunlei
- Abstract
Polyimide (PI) films are used in a wide spectrum of high-tech fields including photovoltaics, microelectronics, and aerospace engineering thanks to their good heat resistance, large mechanical strength, and low thermal expansion coefficients. Further improving their temperature resistance is expected to expand its applications. However, great challenges still exist in the fabrication of PI film with high thermal stability and good combined properties. This review summaries the design strategies and synthesis route of high thermal stability PI films, and discusses the recent progress on improving the thermal stability of PI films by nanocomposite modification. Especically, reported results by introducing a heterocyclic ring into the polymer chain to improve thermal stability were presented. Inorganic particles such as layered silicate, nitrides or metal oxides, carbon nanotubes (CNTs) and graphene used to make organic/inorganic nanocomposite for PI modification were also discussed.
- Published
- 2019
- Full Text
- View/download PDF
7. Vortex beam generator based on exceptional topological phase in terahertz all-dielectric metasurface
- Author
-
Zhang, Yuping, Li, Zhenkai, Jiang, Chunyang, Wang, Kun, Lv, Xinyu, Sang, Xiaotong, Wang, Jian, Liu, Meng, and Zhang, Huiyun
- Abstract
In this study, an all-dielectric metasurface with an F-shaped chiral structure in the terahertz region has been proposed. The coupling between the electric and magnetic dipole modes supported by the metasurface can be adjusted by varying the structural parameters. In the parameter space composed of lland s, any closed path around exceptional point in the circular polarization conversion channel trlgenerates a topologically protected exceptional topological phase. A vortex beam generator with a unit topological charge was proposed to provide a novel concept for designing terahertz metasurface wavefront modulation devices.
- Published
- 2023
- Full Text
- View/download PDF
8. Active manipulation of Dirac semimetals supported chiral coding metasurfaces for multifunctional applications in terahertz region.
- Author
-
Li, Zhenkai, Jiang, Chunyang, Wang, Kun, Liu, Meng, Li, Chuanhao, Tian, Changdong, Zhang, Huiyun, and Zhang, Yuping
- Abstract
• Multifunctional applications of metasurface in terahertz region via coding. • Extended application of coding metasurface in near-field imaging. • Switchable terahertz vortex beam generator was realized. • Arbitrary angle deflection and multi-beam splitting of the vortex beam. Multifunctional coding metasurfaces can provide more options for highly integrated terahertz modulators, which has become one of the current research focus. This study proposed a tunable chiral metasurface based on a Dirac semimetal (DSM). Two U-shaped rings placed perpendicular to each other in the opening direction comprised the metasurface unit cell. Further, the multifunctional application of the metasurface in the terahertz region was realized through coding. The chiral metasurface exhibited strong chirality for incident circularly polarized light with circular dichroism (CD) of up to 0.72 at 2.31 THz. The combination of the chiral metasurface with the Pancharatnam-Berry (PB) phase aided in the realization of a wideband switchable terahertz vortex beam generator, arbitrary angular deflection tuning of the vortex beam, and multi-beam splitting operation of the vortex light using a Fourier convolution operation. In addition, switchable near-field imaging applications were developed by encoding metasurface unit cell cells according to their chirality and amplitude. The results of this study are expected to yield promising applications in future terahertz high-data-capacity communication systems, multi-target information transmission, and controlled near-field imaging. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
9. All-dielectric metasurface-based multimode sensing with symmetry-protected and accidental bound states in the continuum.
- Author
-
Wang, Kun, Liu, Hang, Li, Zhenkai, Liu, Meng, Zhang, Yuping, and Zhang, Huiyun
- Abstract
• An all-dielectric metasurface producing BIC in the THz band was designed. • The resonance type of the BICs was studied by multipole analysis. • The symmetry-protected and accidental BICs ware used for terahertz sensing. • FOM of symmetrically protected BICs reaches 10
8 . • FOM of accidental BICs reaches 105 . Symmetry-protected and accidental bound states in the continuum (BICs) are generated by various triggering mechanisms, and it is challenging to use them together for sensing. This study designed an all-dielectric metasurface that produced BICs in the terahertz band. Moreover, we investigated eight mode distributions by energy band analysis, of which four modes had symmetry-protected BICs at the high-symmetry Γ point, and three had accidental BICs at the non-Γ point, all with quality factors up to 109 . Using multipole analysis and parameter adjustment, we investigated the contribution of multipole moments to the far field, the electromagnetically induced transparency caused by the intermodal coupling, and the merging of accidental BICs. Finally, we used six BICs for multimode sensing, where the figure of merit (FOM) of the symmetry-protected BICs reached 108 , and the FOM of the accidental BICs reached 105 , providing a new perspective on terahertz linear sensor devices. These findings will open a new avenue for the study of terahertz multimode sensors with ultra-high FOM. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
10. Exceptional point in tunable terahertz metasurface based on bulk Dirac semimetal
- Author
-
Yang, Weikui, Li, Zhenkai, Liu, Meng, Zhang, Yuping, and Zhang, Huiyun
- Abstract
In this study, we designed a tunable metasurface using bulk Dirac semimetal, whose periodic unit consisted of two orthogonally oriented split rings with identical dimensions in resonator mode, to observe and study exceptional points (EPs). By changing the Fermi level of the Dirac semimetal, the PT symmetry phase transitioned to the PT symmetry-breaking phase, which enabled the observation of an EP. The proposed method exploits the sensitivity of EPs to the perturbations in the system. The results calculated using the coupled mode theory were consistent with the results of simulations and have significant implications in polarization detection, manipulation, and ultrasensitive sensing.
- Published
- 2023
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.