Multi-Objective Energy Absorption Capability Optimization of Braided Composite Tubes with Improved Trigger

Xu Zhang,Yuanming Xu,Shuming Zhang 한국섬유공학회 2022 Fibers and polymers Vol.23 No.4

With the increased use of composite materials in aircraft main load-bearing structures, it is of great significance tostudy the failure modes and energy absorption characteristics of the structures made up of composite materials. This paperused finite element method (FEM) and investigated the performances of braided composite tubes with semi-circular cavityexternal trigger during crashing. The generated data were used to modify the dynamic Kriging model. Based on the surrogatemodel, the artificial bee colony (ABC) optimization algorithm was used to optimize the cavity radius, tube diameter and tubethickness, so as to minimize the peak load and maximize the specific energy absorption (SEA). The results showed that theKriging model had high accuracy and efficiency in simulating the stress and deformation. The proposed model determinedthe optimized parameters using the ABC model, one of which improved the SEA by 39.6 % and reduced the peak load by38.6 %, thereby improving the structural properties of braided composite materials.

Integration of ZnO nanowires in gated field emitter arrays for large-area vacuum microelectronics applications

Long Zhao,Yuxiang Chen,Yuanming Liu,Guofu Zhang,Juncong She,Shaozhi Deng,Ningsheng Xu,Jun Chen 한국물리학회 2017 Current Applied Physics Vol.17 No.1

Addressable field emitter arrays (FEAs) have important applications in vacuum electronic devices. However, it is important to integrate nanowire emitters into a gated structure without influencing the device structure and maintain the excellent field emission properties of nanowire emitters in the FEAs after the fabrication process. In this study, gate-structure ZnO nanowire FEAs were fabricated by a microfabrication process. The structure combines a planar gate and an under-gate, which is compatible with the preparation of ZnO nanowire emitters. The effect of electrode materials on the field emission properties of ZnO nanowires was studied using a diode structure, and it was found that ZnO nanowire pads on indium-tin-oxide (ITO) electrode showed better field emission performance compared with chromium (Cr) electrode. In addition, effective emission current modulation by the gate voltage was achieved and the addressing capability was demonstrated by integrating the ZnO nanowire FEAs in a vacuum-encapsulated field emission display. The reported technique could be a promising route to achieve large area addressable FEAs.

Facile Synthesis of Block Copolymers from a Cinnamate Derivative by Combination of AGET ATRP and Click Chemistry

Chuanjie Cheng,Xiongxiong Bai,Xu Zhang,Ming Chen,Qinghua Huang,Zhongyu Hu,Yuanming Tu 한국고분자학회 2014 Macromolecular Research Vol.22 No.12

An azido- and bromo-containing compound derived from naturally occurring ethyl cinnamate was usedsuccessfully to prepare block copolymers by a combination of ‘activator generated by electron transfer atom transferradical polymerization’ (AGET ATRP) and Huisgen “click” reactions in emulsion. First, azido-end poly(methyl methacrylate)and alkyne-end polystyrene were prepared under AGET ATRP conditions, then, poly(methyl methacrylate) blockpolystyrene (PMMA-b-PS) diblock copolymer was formed by Huisgen 1,3-dipolar cycloaddition. Finally, polystyreneblock poly(methyl methacrylate) block polystyrene (PS-b-PMMA-b-PS) triblock copolymer was synthesizedvia simultaneous AGET ATRP and click reactions, catalyzed by the same copper-based catalyst. The polymers werecharacterized by 1H nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC),which confirmed the successful synthesis of the corresponding polymers.

An efficient C¹ beam element via multi-scale material adaptable shape function

El-Ashmawy, A.M.,Xu, Yuanming Techno-Press 2022 Advances in nano research Vol.13 No.4

Recently, promising structural technologies like multi-function, ultra-load bearing capacity and tailored structures have been put up for discussions. Finite Element (FE) modelling is probably the best-known option capable of treating these superior properties and multi-domain behavior structures. However, advanced materials such as Functionally Graded Material (FGM) and nanocomposites suffer from problems resulting from variable material properties, reinforcement aggregation and mesh generation. Motivated by these factors, this research proposes a unified shape function for FGM, nanocomposites, graded nanocomposites, in addition to traditional isotropic and orthotropic structural materials. It depends not only on element length but also on the beam's material properties and geometric characteristics. The systematic mathematical theory and FE formulations are based on the Timoshenko beam theory for beam structure. Furthermore, the introduced element achieves C1 degree of continuity. The model is proved to be convergent and free-off shear locking. Moreover, numerical results for static and free vibration analysis support the model accuracy and capabilities by validation with different references. The proposed technique overcomes the issue of continuous properties modelling of these promising materials without discarding older ones. Therefore, introduced benchmark improvements on the FE old concept could be extended to help the development of new software features to confront the rapid progress of structural materials.

Evaluation of secondary cytoreduction surgery in platinum-resistant ovarian cancer patients within three-line recurrent: a multicenter, randomized controlled study

Ting-Ting Chen,Junfen Xu,Bairong Xia,Hui Wang,Yuanming Shen 대한부인종양학회 2024 Journal of Gynecologic Oncology Vol.35 No.1

Background: Epithelial ovarian cancer is the leading cause of death among gynecologicalmalignancies. Platinum resistance remains a dilemma and bottleneck in treatment, andsalvage chemotherapy has limited effectiveness. Recently, the role of secondar y cytoreductivesurger y (SCS) in patients with platinum-resistant recurrent ovarian cancer (ROC) has causedattention especially in patients with oligometastases. However, there is neither high-qualityevidence-based evidence nor standardized criteria for selecting SCS for patients withplatinum-resistant ROC until now. Methods: This multicenter, randomized, controlled clinical trial is to evaluate the valueof SCS and to clarif y reliable criteria of utilizing SCS in women with ROC, which is led byGynecologic Oncology Group, Women’s Hospital, Zhejiang University School of Medicine. Recruitment has started on Januar y 1st, 2023, and is scheduled to end in December 2026. One hundred and forty participants with platinum-resistant ROC who meet the “RSCScriteria” will be randomized assigned at a ratio of 1:1 to either the experimental arm or thestandard arm. Patients in the experimental arm will receive SCS followed by non-platinumsingle agent chemotherapy (paclitaxel, gemcitabine or liposomal adriamycin) for at least4 cycles while patients in the standard arm will be provided with only non-platinum singleagent chemotherapy. The primar y outcome is progression-free sur vival. The secondar youtcomes are overall sur vival, adverse events and health-related cancer-specific quality of life. Trial Registration: ClinicalTrials.gov Identifier: NCT05633199

Expression of RUNX2/LAPTM5 in the Induction of MC3T3-e1 Mineralization and Its Possible Relationship with Autophagy

Xing Lei,Li Yanqin,Li Wenhao,Liu Rong,Geng Yuanming,Ma Weiqun,Qiao Yu,Li Jianwen,Lv Yingtao,Fang Ying,Xu Pingping 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.6

BACKGROUND: The study aims to correlate osteogenesis with autophagy during the mineralization induction of MC3T3-e1 through exploring the expression of runt-related transcription factor 2 (RUNX2)/lysosomal-associated transmembrane protein 5 (LAMPT5). METHODS: The induction of mineralization in MC3T3-e1 was followed by detecting the expressions of osteogenesisrelated indexes such as RUNX2, alkaline phosphatase (ALP), osteocalcin (OCN), and LAPTM5 using RT-qPCR and Western blot from 0 to 14 days. Transmission electron microscope was utilised in visualizing the alterations of autophagosomes, which was followed by immunofluorescence detecting the subcellular localization of autophagy-related index sequestosome 1 (P62) and microtubule-associated protein 1 light 3 (LC3) protein and scrutinising the expression of P62 mRNA and P62 and LC3 proteins. RESULTS: Induction of MC3T3-e1 mineralization demonstrated an increased expression of osteogenesis-related indicators such as RUNX2, ALP, OCN, and LAPTM5 (p\0.05), as evident from the results of RT-qPCR and Western blot. Meanwhile, the expression of autophagosomes increased one day after mineralization induction and then experienced a gradual decline, and enhanced expression of LC3 protein was noted on days 1–2 of mineralization induction but was then followed by a corresponding reduce. In contrast, a continuous increase was reported in the expression of P62 mRNA and protein, respectively (p\0.05). Up- and down-regulating RUNX2/LAPTM5 expression alone confirmed the aforementioned results. CONCLUSION: It was therefore proposed that RUNX2 may be responsible for an early increase and then a gradual decrease in LAPTM5-mediated autophagy through the regulation of its high expression. Meanwhile, increased LAPTM5 expression in osteogenic mineralization presumed that RUNX2/LAPTM5 promoted autophagy and osteogenic expression, which may play a bridging role in the regulation of autophagy and osteogenesis.

Efficacy of lymph node dissection on stage IIICr of cervical cancer before CCRT: study protocol for a phase III, randomized controlled clinical trial (CQGOG0103)

Misi He,Mingfang Guo,Qi Zhou,Ying Tang,Lin Zhong,Qing Liu,Xiaomei Fan,Xiwa Zhao,Xiang Zhang,Gang Chen,Yuanming Shen,Qin Xu,Xiao-jun Chen,Yuancheng Li,Dongling Zou 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.3

Background: Cervical cancer is still present a major public health problem, especially in developing countries. In International Federation of Gynaecology and Obstetrics 2018, allowing assessment of retroperitoneal lymph nodes by imaging and/or pathological findings and, if deemed metastatic, the case is designated as stage IIIC (with r and p notations). Patients with lymph node metastases have lower overall survival (OS), progression free survival (PFS), and survival after recurrence, especially those who have unresectable macroscopical positive lymph nodes. Retrospective analysis suggests that there may be a benefit to debulking macroscopic nodes that would be otherwise difficult to sterilize with standard doses of radiation therapy. However, there are no prospective study reporting that resecting macroscopic nodes before concurrent chemoradiation therapy (CCRT) would improve PFS or OS of cervical cancer and no guidelines for surgical resection of bulky lymph nodes. The CQGOG0103 study is a prospective, multicenter and randomized controlled trial (RCT) evaluating lymph node dissection on stage IIICr of cervical cancer. Methods: Eligible patients are histologically confirmed cervical squamous cell carcinoma, adenocarcinoma, adeno-squamous cell carcinoma. Stage IIICr (confirmed by computed tomography [CT]/magnetic resonance imaging/positron emission tomography/CT) and the short diameter of image-positive lymph node ≥15 mm. 452 patients will be equally randomized to receive either CCRT (pelvic external-beam radiotherapy [EBRT]/extended-field EBRT + cisplatin [40 mg/m2] or carboplatin [the area under curve=2] every week for 5 cycles + brachytherapy) or open/minimally invasive pelvic and para-aortic lymph node dissection followed by CCRT. Randomization is stratified by status of para-aortic lymph node. The primary endpoint is PFS. Secondary endpoints are OS and surgical complications. A total of 452 patients will be enrolled from multiple hospitals in China within 4 years and followed up for 5 years.