Random sampling and reconstruction of signals with finite rate of innovation

Yingchun Jiang,Junjian Zhao 대한수학회 2022 대한수학회보 Vol.59 No.2

In this paper, we mainly study the random sampling and reconstruction of signals living in the subspace $V^p(\Phi,\Lambda)$ of $L^p(\mathbb{R}^d)$, which is generated by a family of molecules $\Phi$ located on a relatively separated subset $\Lambda\subset \mathbb{R}^d$. The space $V^p(\Phi,\Lambda)$ is used to model signals with finite rate of innovation, such as stream of pulses in GPS applications, cellular radio and ultra wide-band communication. The sampling set is independently and randomly drawn from a general probability distribution over $\mathbb{R}^d$. Under some proper conditions for the generators $\Phi=\{\phi_\lambda:\lambda\in \Lambda\}$ and the probability density function $\rho$, we first approximate $V^{p}(\Phi,\Lambda)$ by a finite dimensional subspace $V^{p}_N(\Phi,\Lambda)$ on any bounded domains. Then, we prove that the random sampling stability holds with high probability for all signals in $V^{p}(\Phi,\Lambda)$ whose energy concentrate on a cube when the sampling size is large enough. Finally, a reconstruction algorithm based on random samples is given for signals in $V^{p}_N(\Phi,\Lambda)$.

Hsa_circ_0003221 facilitates the malignant development of bladder cancer cells via resulting in the upregulation of DHCR24 by targeting miR-892b

Peng Lu,Yingchun Jiang,Zongyu Xia 대한비뇨의학회 2022 Investigative and Clinical Urology Vol.63 No.5

Purpose: This research concentrated on the biological effects and special mechanism of circ_0003221 in bladder cancer (BLCA). Materials and Methods: The level quantification by reverse transcription-quantitative polymerase chain reaction was administrated for circ_0003221, microRNA-892b (miR-892b) and 24-dehydrocholesterol reductase (DHCR24). The biological behaviors were assessed by EDU assay and colony formation assay for proliferation, and transwell assay for cell motility. Glycolytic metabolism was tested using the commercial kits. DHCR24 protein level and cell markers were measured through western blot. The analysis of interaction potential was conducted via dual-luciferase reporter assay and pull-down assay. Circ_0003221 was implemented via tumor xenograft assay in vivo. Results: Abnormal circ_0003221 upregulation was affirmed in BLCA. BLCA cell proliferation, motility and glycolysis were impeded after circ_0003221 level was knocked down. MiR-892b was identified as a target for circ_0003221. Reduction of miR-892b relieved si-circ_0003221-induced anti-tumor response in BLCA cells. In addition, miR-892b targeted DHCR24 and circ_0003221/miR-892b could regulate the level of DHCR24. The effects of si-circ_0003221 were also counteracted by DHCR24 overexpression. Conclusions: The current evidence elucidated circ_0003221 targeted miR-892b to elevate the DHCR24 level, thus accelerating cell development and glycolytic metabolism of BLCA cells.

NUMERICAL ANALYSIS OF THE MIXTURE FORMATION IN A TWOSTROKE WALL-GUIDED LPG DI ENGINE FOR EXTENDED-RANGE ELECTRIC VEHICLE

Xu Boyan,Jiang Longlong,Sun Chaodong,Liu Yingchun 한국자동차공학회 2018 International journal of automotive technology Vol.19 No.2

The use of automotive LPG characteristics which are easy to evaporate vaporization and carry. The paper presents a design of extended-range electric vehicle for wall-guided two stroke LPG engine with direct injection combustion system. Based on the modified vehicle LPG spray model, a database describing the characteristics of vehicle LPG fuel was built and imported into the CFD software. And the accuracy of the model is verified by the Schlieren experimental results. The concentration and velocity field of the mixture in the cylinder under different load conditions are numerically analyzed. The analyzed result indicated that the start injection time θ = 60°−70°CA BTDC under part load condition, the plug electrode near the gathering of a richer mixture is easy to be fired at spark ignition time, the obvious formation of mixture in cylinder is formed and the overall air-fuel ratio is above 40 : 1. The start-transition working condition and large load conditions in the piston moves upward before closing the exhaust port to start injection LPG. The optimized LPG injection start time θ ensures that the fresh gas is locked in the cylinder when the exhaust port is closed (63°CA ABDC). In the ignition time of the spark plug, an ideal homogeneous mixture in the cylinder is realized.

The clinical outcomes of fresh versus frozen embryos transfer in women ≥40 years with poor ovarian response

Conghui Liu,Yu Li,Hong Jiang,Yingchun Liu,Xiaomin Song 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.3

ObjectiveTo compare the clinical outcomes of fresh embryo transfers (ETs) and frozen-thawed embryo transfers (FETs) after afreeze-all cycle in women ≥40 years old with poor ovarian response (POR). MethodsWe performed a single-center, retrospective, case-control study of patients who underwent in vitro fertilizationbetween January 2014 and June 2019. We included a total of 192 patients aged 40 years or older from whom 3 orfewer oocytes had been retrieved and who were receiving cleavage-stage ET in this study. Of these patients, 101 and91 patients underwent fresh ET and FET, respectively. The primary outcome was the live birth rate (LBR) after thefirst ET. Logistic regression analysis was used to compare the IVF outcomes and neonatal characteristics between thefresh ET and FET groups, adjusting for maternal age, body mass index, luteinizing hormone, and the number of goodquality embryos transferred. ResultsThe mean maternal ages and number of oocytes retrieved (43.2 years and 2.3 in both groups, P=0.902 and P=0.927,respectively) were similar in the fresh ET and FET groups. No significant difference was observed between the LBRsof the fresh ET and FET groups (adjusted odds ratio, 1.28; 95% confidence interval, 0.29–5.70). The clinical pregnancyand miscarriage rates, and neonatal characteristics (birth weights and premature infant rates) were similar betweenthe 2 groups. ConclusionsFET after the freeze-all strategy had no beneficial impact on the clinical outcomes of women ≥40 years with POR.

Atomic Force Microscopy of Asymmetric Membranes from Turtle Erythrocytes

Tian, Yongmei,Cai, Mingjun,Xu, Haijiao,Ding, Bohua,Hao, Xian,Jiang, Junguang,Sun, Yingchun,Wang, Hongda Korean Society for Molecular and Cellular Biology 2014 Molecules and cells Vol.37 No.8

The cell membrane provides critical cellular functions that rely on its elaborate structure and organization. The structure of turtle membranes is an important part of an ongoing study of erythrocyte membranes. Using a combination of atomic force microscopy and single-molecule force spectroscopy, we characterized the turtle erythrocyte membrane structure with molecular resolution in a quasi-native state. High-resolution images both leaflets of turtle erythrocyte membranes revealed a smooth outer membrane leaflet and a protein covered inner membrane leaflet. This asymmetry was verified by single-molecule force spectroscopy, which detects numerous exposed amino groups of membrane proteins in the inner membrane leaflet but much fewer in the outer leaflet. The asymmetric membrane structure of turtle erythrocytes is consistent with the semi-mosaic model of human, chicken and fish erythrocyte membrane structure, making the semi-mosaic model more widely applicable. From the perspective of biological evolution, this result may support the universality of the semi-mosaic model.

Atomic Force Microscopy of Asymmetric Membranes from Turtle Erythrocytes

Yongmei Tian,Mingjun Cai,Haijiao Xu,Bohua Ding,Xian Hao,Junguang Jiang,Yingchun Sun,Hongda Wang 한국분자세포생물학회 2014 Molecules and cells Vol.37 No.8

The cell membrane provides critical cellular functions that rely on its elaborate structure and organization. The structure of turtle membranes is an important part of an ongoing study of erythrocyte membranes. Using a combination of atomic force microscopy and single-molecule force spectroscopy, we characterized the turtle erythrocyte membrane structure with molecular resolution in a quasi-native state. High-resolution images both leaflets of turtle erythrocyte membranes revealed a smooth outer membrane leaflet and a protein covered inner membrane leaflet. This asymmetry was verified by single-molecule force spectroscopy, which detects numerous exposed amino groups of membrane proteins in the inner membrane leaflet but much fewer in the outer leaflet. The asymmetric membrane structure of turtle erythrocytes is consistent with the semi-mosaic model of human, chicken and fish erythrocyte membrane structure, making the semi-mosaic model more widely applicable. From the perspective of biological evolution, this result may support the universality of the semi-mosaic model.