Temporal gas temperature of atmospheric pressure air plasma

Li Jiayin,Wu Fan,Xian Yubin,Lu Xinpei,Nie Lanlan 한국물리학회 2022 Current Applied Physics Vol.34 No.-

In this paper, temporal gas temperature in plasma was measured by Rayleigh scattering in a passive way since synchronization was difficult due to the randomness of current pulses. The plasma was generated between a 10 mm pin-to-plane gap connected to a H.V DC voltage through a 130 MΩ resistor and a skin sample was placed on a grounded plate. Even the plasma can be touched by a human hand without any feeling of warmth, the peak temperature could be 337 K then decrease to 295 K over 60 μs at 1 mm. Moreover, the applied voltage dramatically affects peak current and the peak temperature. Therefore, the transient “high” temperature cannot be touched and the so-called “cold” plasma might not be “cold”.

Assessment of Myocardial Bridge by Cardiac CT: Intracoronary Transluminal Attenuation Gradient Derived from Diastolic Phase Predicts Systolic Compression

Mengmeng Yu,Yang Zhang,Yuehua Li,Minghua Li,Wenbin Li,Jiayin Zhang 대한영상의학회 2017 Korean Journal of Radiology Vol.18 No.4

Objective: To study the predictive value of transluminal attenuation gradient (TAG) derived from diastolic phase of coronary computed tomography angiography (CCTA) for identifying systolic compression of myocardial bridge (MB). Materials and Methods: Consecutive patients diagnosed with MB based on CCTA findings and without obstructive coronary artery disease were retrospectively enrolled. In total, 143 patients with 144 MBs were included in the study. Patients were classified into three groups: without systolic compression, with systolic compression < 50%, and with systolic compression ≥ 50%. TAG was defined as the linear regression coefficient between intraluminal attenuation in Hounsfield units (HU) and length from the vessel ostium. Other indices such as the length and depth of the MB were also recorded. Results: TAG was the lowest in MB patients with systolic compression ≥ 50% (-19.9 ± 8.7 HU/10 mm). Receiver operating characteristic curve analysis was performed to determine the optimal cutoff values for identifying systolic compression ≥ 50%. The result indicated an optimal cutoff value of TAG as -18.8 HU/10 mm (area under curve = 0.778, p < 0.001), which yielded higher sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy (54.1, 80.5, 72.8, and 75.0%, respectively). In addition, the TAG of MB with diastolic compression was significantly lower than the TAG of MB without diastolic compression (-21.4 ± 4.8 HU/10 mm vs. -12.7 ± 8 HU/10 mm, p < 0.001). Conclusion: TAG was a better predictor of MB with systolic compression ≥ 50%, compared to the length or depth of the MB. The TAG of MB with persistent diastolic compression was significantly lower than the TAG without diastolic compression.

A drug delivery system constructed by a fusion peptide capturing exosomes targets to titanium implants accurately resulting the enhancement of osseointegration peri-implant

Li Xuewen,Liu Zihao,Xu Shendan,Ma Xinying,Zhao Zhezhe,Hu Han,Deng Jiayin,Peng Cheng,Wang Yonglan,Ma Shiqing 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Exosomes derived from bone marrow mesenchymal stem cells (BMSC-exos) have been shown triggering osteogenic differentiation and mineralization of MSCs, but exosomes administered via bolus injections are rapidly sequestered and cleared. Therefore, we considered the implant as a new organ of patient’s body and expected to find a method to treat implant with BMSC-exos in vivo directly.A fusion peptide (PEP), as a drug delivery system (DDS) which contained a titanium-binding peptide (TBP) possessing the ability to selectively bind to the titanium surface and another peptide CP05 being able to capture exosomes expertly, is constructed to modify the titanium surface.Both in vitro and in vivo experiments prove PEP retains the ability to bind titanium and exosome simultaneously, and the DDS gain the ability to target exosomes to titanium implants surface following enhancing osseointegration post-implantation. Moreover, the DDS constructed by exosomes of diverse origins shows the similar combination rate and efficiency of therapy.This drug delivery system demonstrates the concept that EXO-PEP system can offer an accurate and efficient therapy for treating implants with long-term effect.

A General Encryption Algorithm for Different Format Videos

Hao Li,Cheng Yang,Jiayin Tian,Jianbo Liu 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.10

With the rapid development of social network, more and more information is being presented in the form of multimedia, so the security of multimedia files, especially video files, has been capturing the attention of the researchers. Video encryption is widely applied to the DRM system, video conference, medical and military fields and so on. A general video encryption algorithm is proposed to solve the problem that the existing multiple formats (compression formats and container formats) of video requires a unified encryption scheme. Meanwhile, the proposed scheme can not only provide variable levels of security, but also have good performance of compression efficiency and computational complexity, which can ensure that the encrypted video data can be operation.

Prevalence of Decreased Myocardial Blood Flow in Symptomatic Patients with Patent Coronary Stents: Insights from Low-Dose Dynamic CT Myocardial Perfusion Imaging

Yuehua Li,Mingyuan Yuan,Mengmeng Yu,Zhigang Lu,Chengxing Shen,Yining Wang,Bin Lu,Jiayin Zhang 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.4

Objective: To study the prevalence and clinical characteristics of decreased myocardial blood flow (MBF) quantified by dynamic computed tomography (CT) myocardial perfusion imaging (MPI) in symptomatic patients without in-stent restenosis. Materials and Methods: Thirty-seven (mean age, 71.3 ± 10 years; age range, 48–88 years; 31 males, 6 females) consecutive symptomatic patients with patent coronary stents and without obstructive de novo lesions were prospectively enrolled to undergo dynamic CT-MPI using a third-generation dual-source CT scanner. The shuttle-mode acquisition technique was used to image the complete left ventricle. A bolus of contrast media (50 mL; iopromide, 370 mg iodine/mL) was injected into the antecubital vein at a rate of 6 mL/s, followed by a 40-mL saline flush. The mean MBF value and other quantitative parameters were measured for each segment of both stented-vessel territories and reference territories. The MBFratio was defined as the ratio of the mean MBF value of the whole stent-vessel territory to that of the whole reference territory. An MBFratio of 0.85 was used as the cut-off value to distinguish hypoperfused from non-hypoperfused segments. Results: A total of 629 segments of 37 patients were ultimately included for analysis. The mean effective dose of dynamic CT-MPI was 3.1 ± 1.2 mSv (range, 1.7–6.3 mSv). The mean MBF of stent-vessel territories was decreased in 19 lesions and 81 segments. Compared to stent-vessel territories without hypoperfusion, the mean MBF and myocardial blood volume were markedly lower in hypoperfused stent-vessel territories (77.5 ± 16.6 mL/100 mL/min vs. 140.4 ± 24.1 mL/100 mL/min [p < 0.001] and 6.4 ± 3.7 mL/100 mL vs. 11.5 ± 4 mL/100 mL [p < 0.001, respectively]). Myocardial hypoperfusion in stentvessel territories was present in 48.6% (18/37) of patients. None of clinical parameters differed statistically significantly between hypoperfusion and non-hypoperfusion subgroups. Conclusion: Decreased MBF is commonly present in patients who are symptomatic after percutaneous coronary intervention, despite patent stents and can be detected by dynamic CT-MPI using a low radiation dose.

Lightweight Key Distribution Protocol for Streaming Media DRM

Hao Li,Tang Xuyue,Jiayin Tian,Jianbo Liu,Cheng Yang 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.9

In the daily-real systems, protecting the data only is far less enough. The process about the generation, distribution, storage, and the revocation of the key is the core problem in the system-security consideration. If the management of the key is insecure, attackers could easily get the key used in the encryption steps to the context, leading to useless processing in the encryption no matter how secure the system be. Unlike the period of validity for the different key, the key can easily be attacked by various methods due to its distribution through the complex net links, which would bring about the threatening of the security. In this paper, we analyze three models of the key distribution, associated with the actual applications for the encryption in the hypermedia video stream. Besides, we raise up a new protocol based on the IKEV2 distribution protocol and evaluate the stability when it suffer the Man-in –the-Middle Attacks, DoS and Replay attacks.

A highly efficient and selective fluorescent probe for Pd (II) based on benzotriazole-coumarin derivative and its catalytic application in Sonogashira reaction

Shaoheng Li,Ziji Bai,Feiyang Rong,Jiayin Huang,Lipan Zhou,Guodong Feng,Zhiguang Song 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.124 No.-

Palladium-catalyzed coupling reactions have become effective tools for forming new carbon–carbonbonds. In this work, a novel fluorescence active benzotriazole-coumarin derivative, (E)-N’-((1H-benzo[d][1,2,3]triazol-6-yl)methylene)-7-(diethylamino)-2-ox o-2H-chromene-3-carbohydrazide (BTANC),was synthesized as ligand in Pd(II) cation coordination. It is shown that BTANC has a strong fluorescentemission at 483 nm and Pd(II) can effectively quench the fluorescence of BTANC and BTANC shows excellentsensitivity and selectivity towards Pd (II) ions. Otherwise, the BTANC-Pd(II) complex was also testedin the Sonogashira coupling reaction of phenylacetylene and aryl halides. The desired product wasobtained with high yield (up to 99%) under the optimized reaction conditions. More to that, Low fluorescenceemission was observed during the Pd-catalyzed reaction process and the fluorescent emission ofBTANC was recovered at the end of the Pd-catalyzed reaction because the oxidative addition of the arylhalide towards Pd (0) was shut down at the end of the Pd-catalyzed reaction. This fluorescence propertiesof BTANC indicates the feasibility of using fluorescence signal as a potential tool to monitor the completionof the Sonogashira coupling reaction.

Chemokine Signaling Pathway Involved in CCL2 Expression in Patients with Rheumatoid Arthritis

Lin Zhang,Changyi Li,Min Yu,Jiayin Deng,Xing Lv,Jun Liu,Yu Xiao,Wenjie Yang,Yuru Zhang 연세대학교의과대학 2015 Yonsei medical journal Vol.56 No.4

Purpose: Rheumatoid arthritis (RA) is an inflammatory joint disorder, the progressionof which leads to the destruction of cartilage and bone. Chemokines are involvedin RA pathogenesis. In this study, we investigated the chemokine signaling pathway associated with CCL2 in peripheral blood (PB) and synovial tissues (ST) of RA patients based on our previous work about chemokine signaling pathway involvedin the activation of CCL2 production in collagen-induced arthritis rat ST. Materials and Methods: Total RNA was isolated from PB leukocytes and synoviumof the knee joint in both RA patients and control populations. Real-time polymerasechain reaction was used to determine CCL4, CCR5, c-Jun, c-Fos, and CCL2 expressions. Serum level of CCL2 was assessed by enzyme-linked immunosorbent assay, and the production of CCL2 in ST was analyzed immunohistochemically. Results: The expressions of CCL4, CCR5, c-Jun, c-Fos, and CCL2 messenger RNA in RA patients were significantly higher than those in healthy controls, both in ST and on PB leukocyte. Serum CCL2 levels were elevated in RA patients. Histological examination of rheumatoid joints revealed extensive CCL2 expression in RA ST. Conclusion: CCL2, CCL4, c-Jun, c-Fos, and CCR5 may play an important role in the recruitment of PB leukocytes into the RA joints. These data provide evidence that the chemokine signaling pathway is involved in CCL2 expression in RA patient tissues, which may contribute to chronic inflammation associated with RA. Targetingthis signaling pathway may provide a novel therapeutic avenue in RA.

Calcification Remodeling Index Characterized by Cardiac CT as a Novel Parameter to Predict the Use of Rotational Atherectomy for Coronary Intervention of Lesions with Moderate to Severe Calcification

Mengmeng Yu,Yuehua Li,Wenbin Li,Zhigang Lu,Meng Wei,Jiayin Zhang 대한영상의학회 2017 Korean Journal of Radiology Vol.18 No.5

Objective: To assess the feasibility of calcification characterization by coronary computed tomography angiography (CCTA) to predict the use of rotational atherectomy (RA) for coronary intervention of lesions with moderate to severe calcification. Materials and Methods: Patients with calcified lesions treated by percutaneous coronary intervention (PCI) who underwent both CCTA and invasive coronary angiography were retrospectively included in this study. Calcification remodeling index was calculated as the ratio of the smallest vessel cross-sectional area of the lesion to the proximal reference luminal area. Other parameters such as calcium volume, regional Agatston score, calcification length, and involved calcium arc quadrant were also recorded. Results: A total of 223 patients with 241 calcified lesions were finally included. Lesions with RA tended to have larger calcium volume, higher regional Agatston score, more involved calcium arc quadrants, and significantly smaller calcification remodeling index than lesions without RA. Receiver operating characteristic curve analysis revealed that the best cutoff value of calcification remodeling index was 0.84 (area under curve = 0.847, p < 0.001). Calcification remodeling index ≤ 0.84 was the strongest independent predictor (odds ratio: 251.47, p < 0.001) for using RA. Conclusion: Calcification remodeling index was significantly correlated with the incidence of using RA to aid PCI. Calcification remodeling index ≤ 0.84 was the strongest independent predictor for using RA prior to stent implantation.

Seepage characteristics of the leaching solution during in situ leaching of uranium

Zeng Sheng,Song Jiayin,Sun Bing,Wang Fulin,Ye Wenhao,Shen Yuan,Li Hao 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.2

Investigating the seepage characteristics of the leaching solution in the ore-bearing layer during the in situ leaching process can be useful for designing the process parameters for the uranium mining well.We prepared leaching solutions of four different viscosities and conducted experiments using a selfdeveloped multifunctional uranium ore seepage test device. The effects of different viscosities of leaching solutions on the seepage characteristics of uranium-bearing sandstones were examined using seepage mechanics, physicochemical seepage theory, and dissolution erosion mechanism. Results indicated that while the seepage characteristics of various viscosities of leaching solutions were the same in rock samples with similar internal pore architectures, there were regular differences between the saturated and the unsaturated stages. In addition, the time required for the specimen to reach saturation varied with the viscosity of the leaching solution. The higher the viscosity of the solution, the slower the seepage flow from the unsaturated stage to the saturated stage. Furthermore, during the saturation stage, the seepage pressure of a leaching solution with a high viscosity was greater than that of a leaching solution with a low viscosity. However, the permeability coefficient of the high viscosity leaching solution was less than that of a low viscosity leaching solution.