Pump Wavelength Dependence of Photodarkening in Yb-Doped Fibers

Huizi Li,Liling Zhang,Sidharthan, Raghuraman,Ho, Daryl,Xuan Wu,Venkatram, Nalla,Handong Sun,Tianye Huang,Seongwoo Yoo IEEE 2017 Journal of Lightwave Technology Vol.35 No.13

<P>Photodarkening in Yb-doped fibers is known to be dependent of Yb population inversion. In addition to this dependence, we report that pump wavelength selection plays a significant role in photodarkening dynamics. It is found that 976 nm pump source can lead to more severe photodarkening effects than 916 nm pumping at the same inversion levels. This observation is consistent in Yb-doped fibers with various compositions. Our work reveals pump wavelength is another determinant factor of photodarkening besides the inversion level and emphasizes the importance of pump wavelength selection in high power Yb-doped fiber lasers and amplifiers.</P>

MiR-484 Protects Rat Myocardial Cells from Ischemia-Reperfusion Injury by Inhibiting Caspase-3 and Caspase-9 during Apoptosis

Huizi Liu,Sai Li,Wei Jiang,Yinjun Li 대한심장학회 2020 Korean Circulation Journal Vol.50 No.3

Background and Objectives: To reveal the detail mechanism of miR-484 on myocardial ischemia-reperfusion (MI/R) injury. Methods: Rats model of MI/R injury was established based on control (Con; sham operate) group, ischemia-reperfusion (I/R) group, miR-484 treatment (miR) group, and I/R-negative control (IR-C) group, followed by pathological and interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1β expression evaluation. Then the myocardial apoptosis, as well as the expression of miR-484, caspase-3, and caspase-9 in myocardium were examined. Finally, the regulatory relation between miR-484 and SMAD family member 7 (SMAD7) was predicated, followed by verification analysis. Results: Compared with Con group, the expression of miR-484 in I/R and IR-C group was decreased. Compared with I/R and IR-C group, the expression of miR-484 was increased in miR group. Compared with Con group, the expression levels of IL-6, TNF-α, and IL-1β in cardiac myocytes of I/R group and IR-C group were increased. Compared with Con group, the apoptotic index, membrane potential of I/R, and the expression of caspase-3/9 were increased in IR-C group. Compared with the I/R and IR-C groups, the apoptotic index of myocardial cells in the ischemic region was decreased, the membrane potential was increased, and the expression of caspase-3/9 was decreased significantly in the miR group. SMAD7 was the target gene of miR-484. Conclusions: MiR-484 protected myocardial cells from I/R injury by suppressing caspase-3 and caspase-9 expression during cardiomyocyte apoptosis. MiR-484 reduced the expression of IL-6, TNF-α, and IL-1β in MI/R. MiR-484 might alleviate the decreasing of mitochondrial membrane potential in MI/R cells.

Expression of selenium-independent glutathione peroxidase 5 (GPx5) in the epididymis of Small Tail Han sheep

Li, Ruilan,Fan, Xiaomei,Zhang, Tong,Song, Huizi,Bian, Xiaona,Nai, Rile,Li, Jinquan,Zhang, Jiaxin Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.10

Objective: Selenium-independent glutathione peroxidase (GPx5) is specifically expressed in the mammalian epididymis and plays an important role in protecting sperm from reactive oxygen species and lipid peroxidation damage. This study investigates GPx5 expression in the epididymis of Small Tail Han sheep. Methods: GPx5 expression was studied in three age groups: lamb (2 to 3 months), young (8 to 10 months), and adult (18 to 24 months). The epididymis of each age group divided into caput, corpus and cauda, respectively. Analysis the expression quantity of GPx5 in epididymis and testis by real-time fluorescent quantitative polymerase chain reaction and Western blot. Finally, GPx5 protein locating in the epididymis by immunohistochemical. Results: The results demonstrate that in the lamb group, the GPx5 mRNA, but not protein, can be detected. GPx5 mRNA and expressed protein were detected in both the young and adult groups. Moreover, both the mRNA and protein levels of GPx5 were significantly higher in the young group than in other two groups. When the different segments of epididymis were investigated, GPx5 mRNA was expressed in each segment of epididymis regardless of age. Additionally, the mRNA level in the caput was significantly higher than that in corpus and cauda within same age group. The GPx5 protein was in the epithelial cells' cytoplasm. However, GPx5 mRNA and protein were not detected in the testis. Conclusion: These results suggest that GPx5 is mainly expressed in the epididymis of Small Tail Han sheep, and that the expression level of GPx5 is associated with age. Additionally, GPx5 was primarily expressed in the epithelial cells of the caput. Taken together, these studies indicate that GPx5 is expressed in the epididymis in all age grades.

Evaluation of DPWM schemes for Si/SiC three-level hybrid active NPC inverters

Zhuge, Huizi,Zhang, Li,Lou, Xiutao,Lei, Zhengzi,Zou, Yuhang The Korean Institute of Power Electronics 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.11

The hybrid utilization of SiC and Si devices can achieve a trade-of between the efficiency and cost of three-level active neutral-point-clamped (3L-ANPC) inverters. This paper studies a three-phase 2-SiC 3L-hybrid ANPC (3L-HANPC) inverter with different discontinuous pulse width modulation (DPWM) schemes. The principles of these DPWM schemes are analyzed in detail, and carrier-based algorithm for two of the DPWM schemes are given. Finally, a 6 kW three-phase 2-SiC 3L-HANPC inverter prototype was built to compare these two modulation schemes. Experimental results show that DPWM1 with its peak voltage-clamped can achieve a higher efficiency than DPWM2 with its zero-crossing clamped. However, the DPWM2 scheme has a lower THD than the DPWM1 scheme. Since the THD improvement contributed by the DPWM2 scheme is relatively small, the DPWM1 scheme is the preferred DPWM scheme.

Quantitative Evaluation of Gastrocnemius Medialis Stiffness During Passive Stretching Using Shear Wave Elastography in Patients with Parkinson's Disease: A Prospective Preliminary Study

Yin Lu,Du Lijuan,Li Yuanzi,Xiao Yang,Zhang Shiquan,Ma Huizi,He Wen 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.11

Objective: To prospectively investigate the feasibility of shear wave elastography (SWE) as a new quantitative and objective method for evaluating the stiffness of the gastrocnemius medialis (GM) muscle during passive stretching in patients with Parkinson’s disease (PD). Materials and Methods: SWE of the GM muscle was performed in 28 patients with PD [13 female and 15 male; mean age ± standard deviation (SD): 63.0 ± 8.5 years] and 12 healthy controls (5 female and 7 male; mean age ± SD: 59.3 ± 6.4 years) during passive ankle rotation. A Young’s modulus-ankle angle curve was constructed. The GM slack angle and baseline Young’s modulus (E0) were compared between the markedly symptomatic and mildly symptomatic sides of patients with PD, and healthy controls. Additionally, the correlation between the GM slack angle and the severity of rigidity, and the observer reproducibility of SWE in determining the GM slack angle were evaluated. Results: The GM slack angle was smaller on both the markedly and mildly symptomatic sides in patients with PD than in healthy controls (mean ± SD of -29.13° ± 3.79° and -25.65° ± 3.39°, respectively, vs. -21.22° ± 3.52°; p < 0.001 and p = 0.006, respectively). Additionally, in patients with PD, the GM slack angle on the markedly symptomatic side was smaller than that on the mildly symptomatic side (p = 0.003). The E0 value was lower on both the markedly and mildly symptomatic sides in patients with PD than in healthy controls (mean ± SD of 10.11 ± 2.85 kPa and 10.08 ± 1.88 kPa, respectively, vs. 12.23 ± 1.02 kPa; p = 0.012 and p < 0.001, respectively). However, no significant difference was found between the markedly and mildly symptomatic sides in patients with PD (p = 0.634). A negative linear relationship was observed between the GM slack angle and lower limb rigidity score on the markedly symptomatic side in patients with PD (r = -0.719; p < 0.001). The intraclass correlation coefficients for observer reproducibility of SWE ranged from 0.880 to 0.951. Conclusion: The slack angle determined by SWE may be a useful quantitative and reproducible method for evaluating muscle stiffness in patients with PD.

Meta-analysis of randomized controlled trials on the efficacy of daikenchuto on improving intestinal dysfunction after abdominal surgery

Lei Zhang,Yusheng Cheng,Huizi Li,Yufeng Zhou,Bo Sun,Leibo Xu 대한외과학회 2018 Annals of Surgical Treatment and Research(ASRT) Vol.95 No.1

Purpose: Intestinal dysfunction is one of the most common complications in patients after abdominal surgery. Daikenchuto (DKT), a traditional herbal medicine, is recently employed to improve postoperative intestinal dysfunction. The aim of this meta-analysis was to assess the efficacy of DKT in improving intestinal dysfunction after abdominal surgery. Methods: PubMed, Embase, and the Cochrane library were systematically searched to identify randomized controlled trails (RCTs) in adult patients undergoing abdominal surgery, who were randomly distributed to administrate DKT and placebo. The primary outcomes included the time to first postoperative flatus or bowel movement. We used random-effects models to calculate summary mean differences (MDs) with 95% confidence intervals (CIs). Results: Nine RCTs totaling 1,212 patients (618 in DKT, 594 in control group) were included in our study. Compared with control group, DKT can effectively improve postoperative intestinal dysfunction by shortening the time to first postoperative flatus (MD, -0.41; 95% confidence interval [CI], -0.66 to -0.16; P = 0.001) with significant heterogeneity (I<SUP>2</SUP> = 71%, P = 0.004), and bowel movement (MD, -0.65; 95% CI, -0.97 to -0.32; P < 0.001) without significant heterogeneity (I<SUP>2</SUP> = 40%, P = 0.14). Sensitivity analyses by indication of surgery and type of surgery yielded similar results. Conclusion: These data provide limited evidence that DKT shows efficacy on improving intestinal dysfunction after abdominal surgery. However, the results should be interpreted cautiously, due to the heterogeneity of the studies included. Thus, the efficacy of DKT on improving postoperative intestinal dysfunction warrants further investigation.

스마트홈 제품 구매의도에 영향을 미치는 요인 분석 연구: 기술적 신뢰를 매개변수로

조남재,이혜자,정은정,유기섭,Cho, Namjae,Li, HuiZi,Cheong, Eunjeong,Yu, Giseob 한국데이터전략학회 2021 Journal of information technology applications & m Vol.28 No.6

This research is a study on smart homes products, which interest and research are being conducted, because of the recent development of the Internet of Things. Consumer's Purchase intention was set as a dependent variable, and technological trust was used as a mediating variable. We used Technology Acceptance Model as background theory. Perceived ease of use, Perceived usefulness, Security, and Brand were set as independent variables. The results of this study are as follows. First, it was found that perceived ease of use, perceived usefulness, and security significantly affected technological trust that consumers feel. Second, technological trust also had a significant effect on purchase intention, and it was found that perceived ease of use, perceived usefulness, and product security, excluding brands, had an indirect mediating effect on consumers' purchase intention through technological trust. This study is meaningful in that by conducting user-centered research, and results that are partially contrasted with existing studies are derived from increasing the interest of factors we used.