Micromechanical modeling for viscoplastic properties of enzyme degradable semi-crystalline poly (ε-caprolactone)

Xinwei Yang,Cheng Yang,Shujuan Hou,Yiqi Mao 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.11

This work provide theoretical understandings for the enzyme-degradable PCL, and assist its structural designs and engineering applications. An energy-dependent evolution model is developed to reflect the enzyme-triggered decrystallization of crystals and the further dissolution by applying a chain-broken chemical reaction. Then, the mechanical properties of the enzyme-degradable semicrystalline PCL is modelled through the homogenization-based procedure by the volume-average of a collection of laminated inclusions with crystals and amorphous phase. A dual-phase-lag diffusion model is advanced to solve the enzyme concentrations in the PCL. The model is calibrated by the experiments and then applied for the chemomechanical properties of the PCL when under enzyme conditions. Some numerical examples are conducted to discuss effects of the enzyme concentration and the crystallinity on the crystallographic axe evolution as well as the overall chemomechanical properties of the semicrystalline PCL.

Deformation Analysis and Prediction of Pneumatic Probe Based on Fluid-structure Interaction

Yang Fan,Qiu Dexin,Zhao Xinwei,Sai Qingyi,Cai Xiaoshu 한국유체기계학회 2023 International journal of fluid machinery and syste Vol.16 No.1

As an essential tool for measuring flow field, pneumatic probes have gained a wide range of applications. In order to obtain the flow field parameters accurately, it is also crucial to study the deformation of the pneumatic probe structure in flow field. In this paper, the deformation of the conical probe is numerically simulated under the condition of steady incoming flow in the transonic flow field. The fluid-structure interaction and modal analysis methods are used to obtain the deformation and vibration frequency of the probe. The results show that the vibration of the probe is underdamped under the action of two-way fluid-structure interaction, and the total deformation decays exponentially, and the total deformation after stabilization is the same as the result of one-way fluid-structure interaction. For the same material probe, the total deformation changes with time in the same dimensionless expression, and the vibration frequency as well as damping factor do not change due to the variation of flow field. The accuracy of the dimensionless expressions was verified by different incoming flow conditions and the probe material. For the cases studied in this paper, the maximum total deformation, vibration frequency and damping factor of the probe in the flow field can be obtained by using one-way fluid-structure interaction, modal analysis and two-way fluid-structure interaction with a small number of cycles, respectively, so that the total deformation of the probe in the flow field can be predicted over time. The method obtained in this paper can significantly reduce the calculation time for obtaining the probe deformation data in the flow field and improve the work efficiency, which can provide a reference for the design, calibration and application of probes in engineering applications

Ultrathin MEMS thermoelectric generator with Bi2Te3/(Pt, Au) multilayers and Sb2Te3 legs

Liu Yang,Mu Erzhen,Wu Zhenhua,Che Zhanxun,Sun Fangyuan,Fu Xuecheng,Wang Fengdan,Wang Xinwei,Hu Zhiyu 나노기술연구협의회 2020 Nano Convergence Vol.7 No.8

Multilayer structure is one of the research focuses of thermoelectric (TE) material in recent years. In this work, n-type 800 nm ­Bi 2 Te 3 /(Pt, Au) multilayers are designed with p-type ­Sb 2 Te 3 legs to fabricate ultrathin microelectromechanical systems (MEMS) TE devices. The power factor of the annealed ­Bi 2 Te 3 /Pt multilayer reaches 46.5 μW cm −1 K −2 at 303 K, which corresponds to more than a 350% enhancement when compared to pristine ­Bi 2 Te 3 . The annealed ­Bi 2 Te 3 /Au multilayers have a lower power factor than pristine ­Bi 2 Te 3 . The power of the device with ­Sb 2 Te 3 and ­Bi 2 Te 3 /Pt multilayers measures 20.9 nW at 463 K and the calculated maximum output power reaches 10.5 nW, which is 39.5% higher than the device based on ­Sb 2 Te 3 and ­Bi 2 Te 3 , and 96.7% higher than the ­Sb 2 Te 3 and ­Bi 2 Te 3 /Au multilayers one. This work can provide an opportunity to improve TE properties by using multilayer structures and novel ultrathin MEMS TE devices in a wide variety of applications.

Efficiency of Cytokine-Induced Killer Cells in Combination with Chemotherapy for Triple-Negative Breast Cancer

Man Li,Yang Wang,Feng Wei,Xiumei An,Naining Zhang,Shui Cao,Baozhu Ren,Xinwei Zhang,Xiubao Ren 한국유방암학회 2018 Journal of breast cancer Vol.21 No.2

Purpose: The treatment of triple-negative breast cancer (TNBC) remains challenging, due to the absence of estrogen, progesterone, and human epidermal growth factor receptors. This study was designed to evaluate the efficiency and safety of cytokineinduced killer (CIK) cell immunotherapy, following regular chemotherapy, for patients with TNBC. Methods: A total of 340 patients with postmastectomy TNBC, from January 1, 2010 to June 30, 2014, were included in this retrospective study. Seventy-seven patients received CIK cell immunotherapy, following regular chemotherapy (arm 1), and 263 patients received regular chemotherapy alone (arm 2). The primary aim was overall survival (OS) and disease-free survival (DFS), and the treatment responses and adverse events were also evaluated. Results: The 5-year DFS and OS rates in arm 1 were 77.9% and 94.3%, compared with 69.8% and 85.6% in arm 2, respectively (p=0.159 and p=0.035, respectively). This clearly shows that there was no statistical difference in the 5-year DFS between the two groups. Multivariate analyses of arm 1 indicated that a Karnofsky performance score (KPS) ≥90 and stage I/IIA disease were significantly associated with a prolonged DFS period (hazard ratio [HR], 0.25; 95% confidence interval [CI], 0.09–0.74; p=0.012; and HR 0.21; 95% CI, 0.06–0.82; p=0.024, respectively), but a KPS ≥90 and stage I/IIA disease were not independent prognostic factors for OS. Toxicity was mild in patients who received the CIK therapy. Conclusion: The data suggested that CIK cell immunotherapy improved the efficiency of regular chemotherapy in patients with TNBC, and the side effects of CIK cell immunotherapy were mild.

Nodule Rich Protein 2 modulates nodule number in Medicago truncatula

Junhui Yan,Xinwei Yang,Yawen Wang,Liangliang Yu,Li Luo 한국식물생명공학회 2021 Plant biotechnology reports Vol.15 No.1

Symbiotic nitrogen fxation is beneft to sustainable agriculture and global nitrogen cycle. Many small peptides were identifed as regulators involving in the interaction between rhizobia and legume. Here we reported Nodule Rich Protein 2 (MtNRP2) encoding a small peptide in Medicago truncatula, belonged to a group of nodule rich protein restricted in legume species. MtNRP2 expressed highly in root nodule and its promoter was active during the initiation and development of root nodule and lateral root. To investigate the function of MtNRP2 in nodulation, we generated MtNRP2-overexpression and MtNRP2- knockdown transgenic Medicago. MtNRP2-overexpression transgenic lines performed normal nodulation phenotype compared with vector control. However, in the MtNRP2-RNAi transgenic plants, the decrease of MtNRP2 expression lead to the increase of infection threads number (7 day post inoculation) and nodules number (3 week post inoculation); meanwhile, the expression of MtRGF3 and MtPUB1 was inhibited. These results suggested that MtNRP2 negatively regulated nodulation in Medicago truncatula.

Adaptive Frequency-Regualtion Strategy of a DFIG for Enhancing Frequency Support Capability

Mingyi Sun,Xinwei Li,Dejian Yang,Gangui Yan,Lin Yue,Xin Wang 제어로봇시스템학회 2023 제어로봇시스템학회 국제학술대회 논문집 Vol.2023 No.10

KETCH1 imports HYL1 to nucleus for miRNA biogenesis in <i>Arabidopsis</i>

Zhang, Zhonghui,Guo, Xinwei,Ge, Chunxiao,Ma, Zeyang,Jiang, Mengqiu,Li, Tianhong,Koiwa, Hisashi,Yang, Seong Wook,Zhang, Xiuren National Academy of Sciences 2017 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.114 No.15

<P>MicroRNA (miRNA) is processed from primary transcripts with hairpin structures (pri-miRNAs) by microprocessors in the nucleus. How cytoplasmic-borne microprocessor components are transported into the nucleus to fulfill their functions remains poorly understood. Here, we report KETCH1 (karyopherin enabling the transport of the cytoplasmic HYL1) as a partner of hyponastic leaves 1 (HYL1) protein, a core component of microprocessor in Arabidopsis and functional counterpart of DGCR8/Pasha in animals. Null mutation of ketch1 is embryonic-lethal, whereas knockdown mutation of ketch1 caused morphological defects, reminiscent of mutants in the miRNA pathway. ketch1 knockdown mutation also substantially reduced miRNA accumulation, but did not alter nuclear-cytoplasmic shuttling of miRNAs. Rather, the mutation significantly reduced nuclear portion of HYL1 protein and correspondingly compromised the pri-miRNA processing in the nucleus. We propose that KETCH1 transports HYL1 from the cytoplasm to the nucleus to constitute functional microprocessor in Arabidopsis. This study provides insight into the largely unknown nuclear-cytoplasmic trafficking process of miRNA biogenesis components through eukaryotes.</P>

Improved Rotor Speed Strategy of a DFIG for Suppressing Second Frequency Drop

Gan-Gui Yan,Yanfeng Ge,Mingyi Sun,Xinwei Li,Dejian Yang,Xin Wang 제어로봇시스템학회 2023 제어로봇시스템학회 국제학술대회 논문집 Vol.2023 No.10