Geometric Optimization of a Mathematical Model of Radiofrequency Ablation in Hepatic Carcinoma

Wang, Kai-Feng,Pan, Wei,Wang, Fei,Wang, Gao-Feng,Madhava, Pai,Pan, Hong-Ming,Kong, De-Xing,Liu, Xiang-Guan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Radio frequency ablation (RFA) is an effective means of achieving local control of liver cancer. It is a particularly suitable mode of therapy for small and favorably located tumors. However, local progression rates are substantially higher for large tumors (>3.0 cm). In the current study, we report on a mathematical model based on geometric optimization to treat large liver tumors. A database of mathematical models relevant to the configuration of liver cancer was also established. The specific placement of electrodes and the frequency of ablation were also optimized. In addition, three types of liver cancer lesion were simulated by computer guidance incorporating mathematical models. This approach can be expected to provide a more effective and rationale mechanism for employing RFA in the therapy of hepatic carcinoma.

Sialoglycoprotein from Gadous morhua eggs improve high bone turnover activity via down-regulating BMP-2/Smads and Wnt/b-catenin signal pathways

Kai Wang,Lihua Han,Na Wang,Yiming Wang,Jingfeng Wang 한국식품과학회 2018 Food Science and Biotechnology Vol.27 No.5

The effect of sialoglycoprotein isolated from Gadous morhua eggs (Gm-SGP) on ovariectomized (OVX) induced osteoporosis, which is characterized by high bone turnover activity was investigated. Results revealed that Gm-SGP significantly increased bone mineral density, enhanced bone biomechanical properties and repaired the microstructure of the trabecular bone. Also, the treatment with Gm-SGP remarkably decreased biochemical marker contents or activities, such as serum BALP, PICP, BMP-2, TrACP, Cath-K, urine Ca and P, leading to the reduction in bone turnover. The elevation in the rate of bone formative process contributed in the increase of bone turnover. Both BMP-2/Smads and Wnt/b-catenin signaling pathways played an important role in osteogenesis. Gm-SGP suppressed the key factors expression in these two pathways such as BMP-2, Smad1, Smad4, Lrp-5b, Runx2, Osx, ALP, Col1, OCN and b-catenin. These findings might provide some theoretical basis for the application of Gm-SGP as a potential anti-osteoporotic drug or as functional food.

Prognostic Value of MGMT Promoter Methylation and TP53 Mutation in Glioblastomas Depends on IDH1 Mutation

Wang, Kai,Wang, Yin-Yan,Ma, Jun,Wang, Jiang-Fei,Li, Shao-Wu,Jiang, Tao,Dai, Jian-Ping Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.24

Several molecular markers have been proposed as predictors of outcome in patients with glioblastomas. We investigated the prognostic significance of $O^6$-methylguanine-DNA methyltransferase (MGMT) promoter methylation and TP53 mutation status dependent on isocitrate dehydrogenase 1 (IDH1) mutation in glioblastoma patients. A cohort of 78 patients with histologically confirmed glioblastomas treated with radiation therapy and chemotherapy were reviewed retrospectively. We evaluated the prognostic value of MGMT promoter methylation and TP53 mutation status with regard to progression-free survival (PFS) and overall survival (OS). It was revealed that mutations in IDH1, promoter methylation of MGMT, TP53 mutation, age, Karnofsky performance status (KFS), and extension of resection were independent prognostic factors. In patients with an IDH1 mutation, those with an MGMT methylation were associated with longer PFS (p=0.016) and OS (p=0.013). Nevertheless, the presence of TP53 mutation could stratify the PFS and OS of patients with IDH1 wild type (p=0.003 and 0.029 respectively, log-rank). The MGMT promoter methylation and TP53 mutation were associated with a favorable outcome of patients with and without mutant IDH1, respectively. The results indicate that glioblastomas with MGMT methylation or TP53 mutations have improved survival that may be influenced by IDH1 mutation status.

Clinical Application of Transcatheter Arterial Chemoembolization Combined with Synchronous C-arm Cone-Beam CT Guided Radiofrequency Ablation in treatment of Large Hepatocellular Carcinoma

Wang, Zhi-Jun,Wang, Mao-Qiang,Duan, Feng,Song, Peng,Liu, Feng-Yong,Wang, Yan,Yan, Jie-Yu,Li, Kai,Yuan, Kai Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

Objective: This work aimed to evaluate the safety and clinical efficacy of transcatheter arterial chemoembolization (TACE) combined with c-arm cone-beam CT guided synchronous radiofrequency ablation (RFA) in treatment of large hepatocellular carcinoma (HCC). Methods: 21 patients with large HCC were studied from January 2010 to March 2012. TACE combined with synchronous C-arm cone-beam CT guided RFA were performed on a total of 25 lesions. Conventional imaging examination (CEUS, enhanced CT or MRI) and AFP detection were regularly conducted to evaluate the technical success rate of combined treatment, complications, treatment response, time without disease recurrence and survival rate. Results: The technical success rate of combined treatment was 100%, without any significant complication. After 1 month, there were 19 cases with complete response and 2 cases with partial response, with an complete response rate of 90.4% (19/21) and a clinical effective rate of 100% (21/21). The complete response rates of single nodular lesions (100%, 17/17) was significantly higher than that of multiple nodular lesions (50%, 2/4) (P<0. 05). During 2 to 28 months of follow-up, in 19 cases with complete response, the average time without disease recurrence was $10.8{\pm}6$ months. The total survival rates of 6, 12 and 18 months in 21 patients were 100%, respectively. Conclusion: TACE combined with synchronous C-arm CT guided RFA is safe and effective for treatment of large HCC. The treatment efficacy for single nodular lesion is better than that for multiple nodular lesions.

Microstructures and Mechanical Properties of Extruded Mg-Gd-Al Alloys: Influence of Initial Second-Phase Morphology Before Extrusion

Chao Wang,Zhening Yang,Guangxiao Ren,Hongxia Wang,Anguo Zhang,Kai Wang,Jin Wang,Lifei Wang,Kwang Seon Shin 대한금속·재료학회 2024 METALS AND MATERIALS International Vol.30 No.9

The effect of the second-phase morphology on dynamic recrystallisation in a Mg–9Gd–0.8Al alloy during hot extrusion wasinvestigated at a temperature of 400 ℃. Microstructure analysis of the as-cast Mg–9Gd–0.8Al alloy revealed a predominantcomposition comprising an α-Mg matrix, a petal-like (Mg,Al)3Gd phase, and a lamellar Mg5Gdphase along the grain boundary,along with a small proportion of a square Al2Gdphase within the grain. Upon subjecting the alloy to a solid-solutiontreatment at 540 ℃, the lamellar phase underwent precipitation, eventually dissolving into the matrix as the treatment timeincreased. The recrystallisation volume fraction of the alloy showed a positive correlation with the solution time followinghot extrusion at 400 ℃. The mechanical properties of the extruded alloy were tested, and the results revealed that the as-castextruded alloy had the highest tensile strength of 317 MPa among the tested samples, mainly owing to its bimodal structure. Moreover, the broken (Mg,Al)3Gd phase initiated particle-stimulated nucleation. Here, the extruded alloy subjected to10 h of solution treatment exhibited the highest yield strength of 240 MPa. The increased yield strength was attributed tothe presence of the broken (Mg,Al)3Gd phase and the dispersion of lamellar (Mg,Al)2Gd phases at the recrystallised grainboundaries. Notably, the alloy extruded with a treated solution for 50 h exhibited the most favourable plasticity comparedto the others, achieving an elongation of 29.7%. These results underscore the significance of the study in understanding therelationship between the second-phase morphology and alloy behaviour after hot extrusion.

Effect of patient decision aids on choice between sugammadex and neostigmine in surgeries under general anesthesia: a multicenter randomized controlled trial

Wang Li-Kai,Lin Yao-Tsung,Chen Jui-Tai,Lan Winnie,Hung Kuo-Chuan,Chen Jen-Yin,Liu Kuei-Jung,Yen Yu-Chun,Chou Yun-Yun,Cherng Yih-Giun,Tam Ka-Wai 대한마취통증의학회 2023 Korean Journal of Anesthesiology Vol.76 No.4

Background: Shared decision making using patient decision aids (PtDAs) was established over a decade ago, but few studies have evaluated its efficacy in Asian countries. We therefore evaluated the application of PtDAs in a decision conflict between two muscle relaxant reversal agents, neostigmine and sugammadex, and sequentially analyzed the regional differences and operating room turnover rates.Methods: This multicenter, outcome-assessor-blind, randomized controlled trial included 3,132 surgical patients from two medical centers admitted between March 2020 and August 2020. The patients were randomly divided into the classical and PtDA groups for pre-anesthesia consultations. Their clinicodemographic characteristics were analyzed to identify variables influencing the choice of reversal agent. On the day of the pre-anesthesia consultation, the patients completed the four SURE scale (sure of myself, understand information, risk-benefit ratio, encouragement) screening items. The operating turnover rates were also evaluated using anesthesia records. Results: Compared with the classical group, the PtDA group felt more confident about receiving sufficient medical information (P < 0.001), felt better informed about the advantages and disadvantages of the medications (P < 0.001), exhibited a superior understanding of the benefits and risks of their options (P < 0.001), and felt surer about their choice (P < 0.001). Moreover, the PtDA group had a significantly greater tendency to choose sugammadex over neostigmine (P < 0.001). Conclusions: PtDA interventions in pre-anesthesia consultations provided surgical patients with clear knowledge and better support. PtDAs should be made available in other medical fields to enhance shared clinical decision-making.

Reasonably completed state assessment of the self-anchored hybrid cable-stayed suspension bridge: An analytical algorithm

Kai Wang,Wen-ming Zhang,Jie Chen,Zhe-hong Zhang 국제구조공학회 2024 Structural Engineering and Mechanics, An Int'l Jou Vol.90 No.2

In order to solve the problem of calculating the reasonable completed bridge state of a self-anchored hybrid cable-stayed suspension bridge (SA-HCSB), this paper proposes an analytical method. This method simplifies the main beam into a continuous beam with multi-point rigid supports and solves the support reaction forces. According to the segmented catenary theory, it simultaneously solves the horizontal forces of the main span main cables and the stay cables and iteratively calculates the equilibrium force system on the main beam in the collaborative system bridge state while completing the shape finding of the main span main cable and stay cables. Then, the horizontal forces of the side span main cables and stay cables are obtained based on the balance of horizontal forces on the bridge towers, and the shape finding of the side spans are completed according to the segmented catenary theory. Next, the difference between the support reaction forces of the continuous beam with multiple rigid supports obtained from the initial and final iterations is used to calculate the load of ballast on the side span main beam. Finally, the axial forces and strains of each segment of the main beam and bridge tower are obtained based on the loads applied by the main cable and stay cables on the main beam and bridge tower, thereby obtaining analytical data for the bridge in the reasonable completed state. In this paper, the rationality and effectiveness of this analytical method are verified through a case study of a SA-HCSB with a main span of 720m in finite element analysis. At the same time, it is also verified that the equilibrium force of the main beam under the reasonably completed bridge state can be obtained through iterative calculation. The analytical algorithm in this paper has clear physical significance, strong applicability, and high accuracy of calculation results, enriching the shape-finding method of this bridge type.

A Case Study of the Rapid and Long Runout Landslide at Hong′ao Waste Disposal Site in Shenzhen, China

Kai Wang,Shaojie Zhang,Fangqiang Wei,Hongjuan Yang 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.3

A disastrous landslide occurred at the Hong’ao Waste Disposal Site in Shenzhen, China on December 20, 2015, involving a volume of 2.7 × 106 m3 of municipal solid waste (MSW) that travelled a distance of 700 to 800 m, covering an area of 3.8 × 105 m2 and caused 90 casualties. The geomorphological and geological characteristics of the waste disposal site were carefully examined and the landslide was classified as an extremely rapid flowslide. The major feature of the waste site was the basin-like structure with the bottom composed of low-permeable granite bedrock. Therefore, surface runoff could easily accumulate in the MSW due to the lack of drainage system, resulting in an increasing groundwater level. Laboratory tests, including physical characterization, Consolidation Isotropic Undrained (CIU) test and direct shear test were conducted to characterize the material properties of the MSW. Physical characterization indicated the MSW belongs to sandy silt, CIU tests indicated that static liquefaction was conducive to high-speed sliding. The direct shear test data were used to carry out numerical analysis of slope stability, in which the continuous rise in the groundwater level was taken into account. Numerical simulation showed that the pore water pressure induced by underground water seepage and gradual loading from the upper MSW placement aggravate the failure. Consequently, the main reason of the landslide could be concluded as follows: 1) the perched groundwater level due to a large upstream catchment area and the lack of drainage system; 2) the excess pore water pressure induced by static liquefaction played a significant role in its mobility.

Structural health monitoring of high-speed railway tracks using diffuse ultrasonic wave-based condition contrast: theory and validation

Kai Wang,Wuxiong Cao,Zhongqing Su,Pengxiang Wang,Xiongjie Zhang,Lijun Chen,Ruiqi Guan,Ye Lu 국제구조공학회 2020 Smart Structures and Systems, An International Jou Vol.26 No.2

Despite proven effectiveness and accuracy in laboratories, the existing damage assessment based on guided ultrasonic waves (GUWs) or acoustic emission (AE) confronts challenges when extended to real-world structural health monitoring (SHM) for railway tracks. Central to the concerns are the extremely complex signal appearance due to highly dispersive and multimodal wave features, restriction on transducer installations, and severe contaminations of ambient noise. It remains a critical yet unsolved problem along with recent attempts to implement SHM in bourgeoning high-speed railway (HSR). By leveraging authors' continued endeavours, an SHM framework, based on actively generated diffuse ultrasonic waves (DUWs) and a benchmark-free condition contrast algorithm, has been developed and deployed via an all-in-one SHM system. Miniaturized lead zirconate titanate (PZT) wafers are utilized to generate and acquire DUWs in long-range railway tracks. Fatigue cracks in the tracks show unique contact behaviours under different conditions of external loads and further disturb DUW propagation. By contrast DUW propagation traits, fatigue cracks in railway tracks can be characterised quantitatively and the holistic health status of the tracks can be evaluated in a real-time manner. Compared with GUW- or AE-based methods, the DUW-driven inspection philosophy exhibits immunity to ambient noise and measurement uncertainty, less dependence on baseline signals, use of significantly reduced number of transducers, and high robustness in atrocious engineering conditions. Conformance tests are performed on HSR tracks, in which the evolution of fatigue damage is monitored continuously and quantitatively, demonstrating effectiveness, adaptability, reliability and robustness of DUW-driven SHM towards HSR applications.

Optimal design of porous baffle to improve the flow distribution in the tube-side inlet of a shell and tube heat exchanger

Wang, Kai,Tu, Xin-Cheng,Bae, Chan-Hyo,Kim, Hyoung-Bum Elsevier 2015 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.80 No.-

<P><B>Abstract</B></P> <P>An optimization study of a porous plate to improve the flow distribution in the tube side of a shell and tube heat exchanger was performed using numerical and experimental methods. The first assumption in the design stage of multichannel heat exchangers is that there is an even flow distribution along the multi channels. However, this assumption is generally not upheld in real situations. An experimental study was first performed to confirm the effectiveness of a porous baffle in improving the flow distribution in the tube side of a shell and tube heat exchanger. The results showed that the baffle can largely decrease maldistribution. We then performed numerical optimization of the porous baffle shape. The optimized curvature of a porous plate and the distribution of circular holes in the baffle were determined using the numerical method. The optimization results showed that the area-weighted averaged absolute error of the flow rate of the optimized baffle decreased to one-third that of the proto-type baffle model. For validation of the numerical optimization, the flow field with the optimized baffle was measured. Although there were some differences between the experimental and the numerical results, the results showed that the flow distribution using the optimized model was largely improved compared with that of the proto-type porous baffle.</P>