MRI T2-Weighted Imaging and Fat-Suppressed T2-Weighted Imaging Image Fusion Technology Improves Image Discriminability for the Evaluation of Anal Fistulas

Shi-Ting Feng,Mengqi Huang,Zhi Dong,Ling Xu,Yin Li,Yingmei Jia,Huasong Cai,Bingqi Shen,Zi-Ping Li 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.3

Objective: To explore whether MRI fusion technology (combined T2-weighted imaging [T2WI] and fat-suppressed T2WI [T2WI-FS]) improves signal differences between anal fistulas and surrounding structures. Materials and Methods: A total of 32 patients with confirmed diagnoses of anal fistula were retrospectively studied. All available T2WI and T2WI-FS images for each patient were used to generate fusion image (T2WI-Fusion) based on the addition of gray values obtained from each pixel via an MR post-processing work station. The discriminability of fistula, perianal sphincter, and perianal fat in T2WI, T2WI-FS, and T2WI-Fusion images was quantified with Fisher’s scoring algorithm. For subjective visual image assessment by researchers, five-point scale scores were determined using a modified double-stimulus continuous qualityscale test to evaluate T2WI-FS, T2WI, enhanced axial three-dimensional-volumetric interpolated breath-hold examination (3D-VIBE), and T2WI-Fusion sequence images. The differences were subsequently compared. Results: Mean Fisher scores for fistulas vs. sphincters obtained from T2WI-Fusion (FFusion-fistula = 6.56) were significantly higher than those from T2WI (FT2WI-fistula = 3.35) (p = 0.001). Mean Fisher scores for sphincters vs. fat from T2WI-Fusion (FFusion-sphincter = 10.84) were significantly higher than those from T2WI-FS (FSFS-sphincter = 2.57) (p = 0.001). In human assessment, T2WI-Fusion showed the same fistula discriminability as T2WI-FS, and better sphincter discriminability than T2WI. Overall, T2WI-Fusion showed better discriminability than T2WI, T2WI-FS, and enhanced 3D-VIBE images. Conclusion: T2WI and T2WI-FS fusion technology improves signal differences between anal fistulas and surrounding structures, and may facilitate better evaluation of anal fistulas and sphincters.

Fluctuation Power Control Strategy for MMC-based SST to Reduce the Submodule Capacitor Voltage Oscillation

Xiaolong Cai,Jianwen Zhang,Gang Shi,Xu Cai,Jianqiao Zhou,Zhuyong Li,Jiacheng Wang,Jiajie Zang 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

In the future AC-DC hybrid distribution system, solid state transformer (SST) will take place of conventional transformer, as it could reduce the weight and volume of transformer, and achieve voltage and current regulation, power flow control, power quality enhancement. MMC-based SST is a novel SST topology, which could provide the MVDC port. However, the excessive bulky submodule capacitors limits this topology into practical application. This paper proposes a fluctuation power control strategy for MMC-based SST to reduce the submodule capacitor voltage oscillation, which could optimize the capacitance and reduce the volume and cost of capacitor. The feasibility of this proposed method is verified by MATLAB simulation.

Vibration analysis of damaged core laminated curved panels with functionally graded sheets and finite length

Li-Cai Zhao,Shi-Shuenn Chen,Yi-Peng Xu,Vahid Tahouneh 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.38 No.5

The main objective of this paper is to study vibration of sandwich open cylindrical panel with damaged core and FG face sheets based on three-dimensional theory of elasticity. The structures are made of a damaged isotropic core and two external face sheets. These skins are strengthened at the nanoscale level by randomly oriented Carbon nanotubes (CNTs) and are reinforced at the microscale stage by oriented straight fibers. These reinforcing phases are included in a polymer matrix and a three-phase approach based on the Eshelby-Mori-Tanaka scheme and on the Halpin-Tsai approach, which is developed to compute the overall mechanical properties of the composite material. Three complicated equations of motion for the panel under consideration are semi-analytically solved by using 2-D differential quadrature method. Several parametric analyses are carried out to investigate the mechanical behavior of these multi-layered structures depending on the damage features, through-the-thickness distribution and boundary conditions. It is seen that for the large amount of power-law index “P”, increasing this parameter does not have significant effect on the non-dimensional natural frequency parameters of the FG sandwich curved panel. Results indicate that by increasing the value of isotropic damage parameter “D” up to the unity (fully damaged core) the frequency would tend to become zero. One can dictate the fiber variation profile through the radial direction of the sandwich panel via the amount of “P”, “b” and “c” parameters. It should be noticed that with increase of volume fraction of fibers, the frequency parameter of the panels does not increase necessarily, so by considering suitable amounts of power-law index “P” and the parameters “b” and “c”, one can get dynamic characteristics similar or better than the isotropic limit case for laminated FG curved panels.

Metabolomic analysis of biochemical changes in the tissue and urine of proteoglycan-induced spondylitis in mice after treatment with moxibustion

Xiao Xu,Ya-Nan Shi,Rong-Yun Wang,Cai-Yan Ding,Xiao Zhou,Yu-Fei Zhang,Zhi-Ling Sun,Zhi-Qin Sun,Qiu-Hua Sun 한국한의학연구원 2021 Integrative Medicine Research Vol.10 No.1

Background: Moxibustion is widely used in East Asian countries to manage the symptom of rheumatic diseases. The aim of this study was to identify potential metabolic profiles of moxibustion on relieving ankylosing spondylitis (AS) mice through UHPLC-Q-TOF/MS metabolomic study. Methods: Thirty-two female Balb/c mice were randomized into healthy control (HC), AS model, moxibustion at acupuncture points (MA) in AS model, and moxibustion at non-acupuncture points (MNA) AS model groups. Moxibustion was administered daily at GV4, bilateral BL23 and bilateral ST36 acupuncture points for four weeks in the MA group. The overall health status, the thickness of hind paws and the tissue concentrations of IL-1β, PGE2, IL-6 and TNF-α were assessed. The UHPLC-Q-TOF/MS was used to explore the perturbations of endogenous metabolites in tissue and urine of AS model mice intervened by moxibustion. Results: Compared with the AS group, the overall health status was significantly improved after 4-week moxibustion intervention (p < 0.05). The results also showed that MA significantly reduced the levels of paw thickness and decreased the levels of four cytokines in the tissue (p < 0.01). Thirty-seven endogenous metabolites identified by the OPLS-DA were considered to be contributing to therapeutic effects of moxibustion. Moreover, metabolic pathway analysis further revealed that the identified metabolites were mainly involved in TCA cycle, Lipid metabolism, Amino Acid metabolism, Intestinal flora metabolism and Purine metabolism. Conclusions: UHPLC-Q-TOF/MS based metabolomics approach, as a novel and powerful tool, can help us to gain the insights into potential mechanisms of action of moxibustion for AS.

Fabricating Cu2O-CuO submicron-cubes for efficient catalytic CO oxidation: The significant effect of heterojunction interface

Yiyu Shi,Leilei Xu,Mindong Chen,Bo Yang,Ge Cheng,Cai-e Wu,Zhichao Miao,Ning Wang,Xun Hu 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.105 No.-

In this work, the uniform Cu2O submicron-cubes were facilely synthesized by liquid phase reductionmethod. Then, the Cu2O submicron-cubes were further oxidized into Cu2O-CuO heterojunction with tunableCu2+/Cu+ ratios and CuO submicron-cubes by controlling the calcination temperature. The phasetransition period during calcination was real-time monitored by the in-situ XRD and in-situ DRIFTS. The obtained materials were investigated as the catalysts of CO oxidation. The results revealed thatthe Cu2O-CuO heterojunction catalysts performed much higher catalytic activities than the Cu2O andCuO counterparts. Because the synergistic effect of the heterojunction (Cu2+/Cu+) could increase the surfaceoxygen vacancy concentration. Furthermore, it was also found that only the Cu2O-CuO heterojunctionstructure with the appropriate Cu2+/Cu+ ratio behaved the optimum catalytic activity. The kineticstudies indicated that the apparent activation energy of CO oxidation was greatly affected by the Cu2+/Cu+ ratio. Therefore, these Cu2O-CuO submicron-cubes with heterostructure were considered as thepromising CO oxidation catalysts.

Dimensionless study on dynamics of pressure controlled mechanical ventilation system

Yan Shi,Jinglong Niu,Maolin Cai,Weiqing Xu 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.2

Dynamics of mechanical ventilation system can be referred in pulmonary diagnostics and treatments. In this paper, to convenientlygrasp the essential characteristics of mechanical ventilation system, a dimensionless model of mechanical ventilation system is presented. For the validation of the mathematical model, a prototype mechanical ventilation system of a lung simulator is proposed. Through thesimulation and experimental studies on the dimensionless dynamics of the mechanical ventilation system, firstly, the mathematical modelis proved to be authentic and reliable. Secondly, the dimensionless dynamics of the mechanical ventilation system are obtained. Last, theinfluences of key parameters on the dimensionless dynamics of the mechanical ventilation system are illustrated. The study provides anovel method to study the dynamic of mechanical ventilation system, which can be referred in the respiratory diagnostics and treatment.

Senescence Effects of Angelica sinensis Polysaccharides on Human Acute Myelogenous Leukemia Stem and Progenitor Cells

Liu, Jun,Xu, Chun-Yan,Cai, Shi-Zhong,Zhou, Yue,Li, Jing,Jiang, Rong,Wang, Ya-Ping Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Leukemia stem cells (LSCs) play important roles in leukemia initiation, progression and relapse, and thus represent a critical target for therapeutic intervention. Hence, it is extremely urgent to explore new therapeutic strategies directly targeting LSCs for acute myelogenous leukemia (AML) therapy. We show here that Angelica sinensis polysaccharide (ASP), a major active component in Dong quai (Chinese Angelica sinensis), effectively inhibited human AML $CD34^+CD38^-$ cell proliferation in vitro culture in a dose-dependent manner while sparing normal hematopoietic stem and progenitor cells at physiologically achievable concentrations. Furthermore, ASP exerted cytotoxic effects on AML K562 cells, especially LSC-enriched $CD34^+CD38^-$ cells. Colony formation assays further showed that ASP significantly suppressed the formation of colonies derived from AML $CD34^+CD38^-$ cells but not those from normal $CD34^+CD38^-$ cells. Examination of the underlying mechanisms revealed that ASP induced $CD34^+CD38^-$ cell senescence, which was strongly associated with a series of characteristic events, including up-regulation of p53, p16, p21, and Rb genes and changes of related cell cycle regulation proteins P16, P21, cyclin E and CDK4, telomere end attrition as well as repression of telomerase activity. On the basis of these findings, we propose that ASP represents a potentially important agent for leukemia stem cell-targeted therapy.

Electrostatic self‑assembly cellulose nanofibers/MXene/nickel chains for highly stable and efficient seawater evaporation and purification

Shuai Yang,Cai Shi,Keqi Qu,Zhe Sun,Handong Li,Benbin Xu,Zhanhua Huang,Zhanhu Guo 한국탄소학회 2023 Carbon Letters Vol.33 No.7

Seawater evaporation and purification powered by solar energy are considered as a promising approach to alleviate the global freshwater crisis, and the development of photothermal materials with high efficiency is imminent. In this study, cellulose nanofiber (CNF)/MXene/Ni chain (CMN) aerogels were successfully synthesized by electrostatic force and hydrogen bond interaction force. CMN10 achieved a favorable evaporation rate as high as 1.85 kg m? 2 h? 1 in pure water, and the corresponding evaporation efficiency could be up to 96.04%. Even if it is applied to seawater with multiple interference factors, its evaporation rate can still be 1.81 kg m? 2 h? 1. The superior seawater evaporation activity origins from the promoted separation of photoexcited charges and photothermal conversion by the synergy of Ni chain and MXene, as well as the water transport channel supported by the 3D structure frame of CNF. Most importantly, CMN aerogel can maintain water vapor evaporation rates above 1.73 kg m? 2 h? 1 under extreme conditions such as acidic (pH 2) and alkaline (pH 12) conditions. In addition, various major ions, heavy metals and organic pollutants in seawater can be rejected by CMN10 during desalination, and the rejection rates can reach more than 99.69%, ensuring the purity of water resources after treatment. This work shows the great potential of CMN aerogel as a high-efficiency solar evaporator and low-cost photothermal conversion material. Cellulose nanofiber (CNF)/MXene/Ni chain (CMN) aerogels demonstrated high evaporation of water from sea water.

EXPERIMENTAL STUDY OF EGR COOLER REGENERATION AIDED BY OXYGEN-FED NTP AND AIR-FED NTP

Y. X. SHI,Y. ZHENG,Y. X. CAI,W. J. LI,H. XU 한국자동차공학회 2016 International journal of automotive technology Vol.17 No.3

Based on non-thermal plasma (NTP) technology fed by oxygen and air as the gas source respectively, the experimental system of exhaust gas recirculation (EGR) cooler regeneration was built to do a study at different regeneration temperatures. By measuring the concentration of main active substance and COx in regeneration process, the influence of temperature on regeneration aided by oxygen-fed NTP and air-fed NTP was investigated. The experimental results indicate that EGR cooler can be regenerated both by air-fed NTP and oxygen-fed NTP at a wide temperature range of 18 oC ~ 300 oC. By comparison of the regeneration with oxygen-fed NTP and air-fed NTP, it can be easily known that the regeneration effect is most remarkable at 150 oC with oxygen-fed NTP and at 120 oC with air-fed NTP. In addition, when the temperature is below 150 oC especially at 120 oC, the regeneration efficiency of air-fed NTP is lower than oxygen-fed NTP, nevertheless, when the temperature is above 150 oC, air-fed NTP has a superiority in regeneration and the higher the temperature is, the more obvious the superiority will be.

Tribological properties of Ti-4Si-xZr-yY2O3/ 5TiO2 Composites Prepared by High-Energy Milling,Cold Pressing and Sintering

Vitus Mwinteribo Tabie,Xiaodong Shi,Jianwei Li,Chengbin Cai,Xiaojing Xu 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.11

In the present study, tribological properties of Ti–4Si–xZr–yY2O3/5TiO2 were investigated. Four composites; Ti–4Si/5TiO2, Ti–4Si–1.3Zr/5TiO2, Ti–4Si–0.3Y2O3/5TiO2 and Ti–4Si–1.3Zr–0.3Y2O3/5TiO2 were fabricated by high-energy milling and cold pressing method. The composites showed enhanced wear and friction resistance against Si3N4 spheres counterface. The hardness and wear resistance of the composite increased with the addition of rare earth and Zirconium. Ti–4Si–1.3Zr–0.3Y2O3/5TiO2 composite has the smallest wear scar (222 μm) showing good wear resistance. Fatigue wear, supplemented by abrasive, oxidative and adhesive wears were identified as the predominant wear mechanisms. The study also found that rare earth Y2O3 can significantly improve the wear resistance of composites as it reduces the friction coefficient of Ti–4Si–1.3Zr/5TiO2 composite by about 25%.