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1.
一种基于LINC发射机系统的信号分离实现方法   总被引:2,自引:0,他引:2  
LINC发射机是使用非线性但是高效率的射频功率放大器来实现信号的线性放大。在LINC系统中,信号分离部分(SCS)是LINC系统中非常重要的信号处理过程,直接影响LINC系统线性度及效率的提高。对目前存在的几种信号分离实现方法就占用逻辑资源、运行速度等方面进行比较后,采用了一种优化实现方法,并对信号分离部分及LINC系统做出了仿真论证,完成了LINC线性高效功率放大。  相似文献   
2.
Tong MA  Fafen WANG  Xiaohui WANG 《Biocell》2019,43(3):191-198
Cervical cancer (CC), has been identified as one of the most frequent malignant tumors all over the world, with high mortality in females. A growing number of investigations have confirmed that long noncoding RNAs (lncRNAs) play a crucial role in the progression of multiple cancers. Nonetheless, the biological function and regulatory mechanism of LINC01772 in CC haven’t been explored so far. In this study, LINC01772 expression was found to be upregulated in tissues and cells of CC. Knocking down LINC01772 suppressed CC cell proliferation, migration and epithelial-mesenchymal transition (EMT) process. Through molecular mechanism assays, LINC01772 was verified to be bound with miR-3611 and LINC01772 acted as a sponge for miR-3611. Zinc finger E-box binding homeobox 1 (ZEB1) was a downstream target gene of miR-3611. ZEB1 was negatively regulated by miR-3611 but positively regulated by LINC01772. Rescue assays confirmed that miR-3611 inhibitor or ZEB1 overexpression offset the inhibitive effect of LINC01772 depletion on cell proliferation, migration and EMT process in CC. In a word, our study validated that LINC01772 promoted cell metastasis and EMT process in CC by sponging miR-3611 to upregulate ZEB1 expression, indicating that LINC01772 could serve as a new therapeutic target for patients with CC.  相似文献   
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4.
韩越  乔树山  黑勇 《半导体学报》2014,35(11):115001-9
The linear amplification with nonlinear component transmitter is a promising solution to high efficiency and high linearity amplification for non-constant envelope signals.An all-digital synthesizable baseband for a delay-based LINC transmitter is implemented.This paper proposes a standard-cell based synthesizable methodology which can be applied in the ASIC process efficiently without performance degradation compared to the manual layout.A scheme to overcome the limited resolution of conventional phase detectors is proposed.It employs alternative phase detector structures to provide reconfigurability for higher resolution after fabricating,resulting in an11 ps resolution improvement.Due to the PVT variation,an adaptive calibration scheme focusing on the inherent imbalance between two delay lines is depicted,which reveals an effective EVM enhancement of 5.37 d B.This baseband chip is implemented in 0.13 m CMOS technology,and the transmitter with the baseband has an EVM of –28.96 d B and an ACPR of –29.51 d B,meeting the design requirement.  相似文献   
5.
In this article, a novel adaptive bias LInear amplification with Nonlinear Components (LINC) transmitter is introduced and analyzed. Predistortion is applied to the baseband signal and the bias of the high‐efficiency power amplifier is adaptively changed according to the envelope distribution of the baseband signal and the power amplifier itself. This novel transmitter can simultaneously achieve high average efficiency and linearity even with a high peak to average ratio signal. A comprehensive simulation framework has been developed using EDA software to validate this adaptive bias scheme with 16, 32, and 64 quadrature amplitude modulation signals. The simulation results show that this novel scheme can help in improving the average overall efficiency of the LINC transmitter by 15% while sustaining expected linearity. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.  相似文献   
6.
The LINC (LInker of Nucleoskeleton and Cytoskeleton) complex is localized within the nuclear envelope and consists of SUN (Sad1/UNc84 homology domain-containing) proteins located in the inner nuclear membrane and KASH (Klarsicht/Anc1/Syne1 homology domain-containing) proteins located in the outer nuclear membrane, hence linking nuclear with cytoplasmic structures. While the nucleoplasm-facing side acts as a key player for correct pairing of homolog chromosomes and rapid chromosome movements during meiosis, the cytoplasm-facing side plays a pivotal role for sperm head development and proper acrosome formation during spermiogenesis. A further complex present in spermatozoa is involved in head-to-tail coupling. An intact LINC complex is crucial for the production of fertile sperm, as mutations in genes encoding for complex proteins are known to be associated with male subfertility in both mice and men. The present review provides a comprehensive overview on our current knowledge of LINC complex subtypes present in germ cells and its central role for male reproduction. Future studies on distinct LINC complex components are an absolute requirement to improve the diagnosis of idiopathic male factor infertility and the outcome of assisted reproduction.  相似文献   
7.
韩越  乔树山  黑勇 《半导体学报》2016,37(1):015003-7
In order to overcome the bottleneck of low linearity and low resolution, an improved delay line structure is proposed with a calibration algorithm to conquer PVT (process, voltage and temperature) variations for an all-digital design. The chip is implemented in 0.13 μ m CMOS technology. Measurement results show that the proposed structure with the calibration algorithm can evidently improve the linearity and resolution of the delay line. The delay resolution is 2 ps and the root mean square jitter of the delay is 4.71 ps, leading to an error vector magnitude enhancement of 1.32 dB.  相似文献   
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崔华  燕红霞  尹梅 《金属学报》2021,26(6):616-623
目的:研究下调lncRNA LINC00176对肺癌A549/DDP细胞顺铂耐药和自噬的影响及机制。方法:qRT-PCR方法测定正常支气管上皮16HBE细胞和肺癌A549、A549/DDP、NCI-H1299、SK-MES-1细胞中LINC00176的表达。将A549/DDP细胞分成对照组、si-NC组、si-LINC00176组、si-LINC00176+Anti-miR-NC组、si-LINC00176+Anti-miR-138-5p组。MTT实验检测顺铂对A549/DDP的半数抑制浓度(IC50)。流式细胞术测定细胞凋亡。Western blot测定LC3-I、LC3-II、Beclin 1、C-Caspase-3蛋白表达。利用荧光素酶报告系统鉴定LINC00176和miR-138-5p的靶向关系。结果:与16HBE细胞比较,A549、A549/DDP、NCI-H1299、SK-MES-1细胞中LINC00176表达水平显著升高(P<0.01)。与A549细胞比较,A549/DDP细胞中LINC00176表达水平显著升高(P<0.01)。与对照组、si-NC组比较,si-LINC00176组A549/DDP细胞IC50显著降低(P<0.01),LC3-II/LC3-I、Beclin 1蛋白表达显著降低(P<0.01),凋亡率、C-Caspase-3蛋白表达、miR-138-5p表达水平显著升高(P<0.01)。LINC00176与miR-138-5p直接结合。与si-LINC00176+Anti-miR-NC组比较,si-LINC00176+Anti-miR-138-5p组A549/DDP细胞IC50显著升高(P<0.01),LC3-II/LC3-I、Beclin 1蛋白表达显著升高(P<0.01),凋亡率、C-Caspase-3蛋白表达显著降低(P<0.01)。 结论:下调lncRNA LINC00176通过靶向上调miR-138-5p能够抑制肺癌A549/DDP细胞顺铂耐药,抑制细胞自噬,诱导细胞凋亡。  相似文献   
10.
Long non-coding RNAs (lncRNAs) have structural and functional roles in development and disease. We have previously shown that the LINC00961/SPAAR (small regulatory polypeptide of amino acid response) locus regulates endothelial cell function, and that both the lncRNA and micropeptide counter-regulate angiogenesis. To assess human cardiac cell SPAAR expression, we mined a publicly available scRNSeq dataset and confirmed LINC00961 locus expression and hypoxic response in a murine endothelial cell line. We investigated post-natal growth and development, basal cardiac function, the cardiac functional response, and tissue-specific response to myocardial infarction. To investigate the influence of the LINC00961/SPAAR locus on longitudinal growth, cardiac function, and response to myocardial infarction, we used a novel CRISPR/Cas9 locus knockout mouse line. Data mining suggested that SPAAR is predominantly expressed in human cardiac endothelial cells and fibroblasts, while murine LINC00961 expression is hypoxia-responsive in mouse endothelial cells. LINC00961–/– mice displayed a sex-specific delay in longitudinal growth and development, smaller left ventricular systolic and diastolic areas and volumes, and greater risk area following myocardial infarction compared with wildtype littermates. These data suggest the LINC00961/SPAAR locus contributes to cardiac endothelial cell and fibroblast function and hypoxic response, growth and development, and basal cardiovascular function in adulthood.  相似文献   
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