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Lyu J, Chen L, Wen R, Long P, Shang L, Hu L. [Structural Design and Penumbra Analysis of Dynamic Multi-leaf Collimator Leaf End]. Zhongguo Yi Liao Qi Xie Za Zhi 2023; 47:377-382. [PMID: 37580286 DOI: 10.3969/j.issn.1671-7104.2023.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
Dynamic multi-leaf collimator, which has the function of radiation beam shaping, is a key executive component of tumor precise radiotherapy, and plays a core role in improving the accuracy, efficiency and quality of radiotherapy. A new type of collimator leaf end structure with circular arc and plane combination was studied, and collimator penumbra performance analysis model combining analytical expression and graphic analysis was developed. The influence of leaf end structure on penumbra was analyzed quantitatively, and a set of three-dimensional structure design of dynamic multi-leaf collimator was completed. The feasibility of the structural design and analysis model was verified through experimental measurements.
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Affiliation(s)
- Jun Lyu
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031
- University of Science and Technology of China, Hefei, 230026
| | - Liuli Chen
- SuperAccuracy Science & Technology Co. Ltd., Nanjing, 210044
- Institute of SuperAccuracy Advanced Technology Co. Ltd., Hefei, 230088
| | - Ruijun Wen
- SuperAccuracy Science & Technology Co. Ltd., Nanjing, 210044
| | - Pengcheng Long
- SuperAccuracy Science & Technology Co. Ltd., Nanjing, 210044
- Institute of SuperAccuracy Advanced Technology Co. Ltd., Hefei, 230088
| | - Leiming Shang
- SuperAccuracy Science & Technology Co. Ltd., Nanjing, 210044
- Institute of SuperAccuracy Advanced Technology Co. Ltd., Hefei, 230088
| | - Liqin Hu
- SuperAccuracy Science & Technology Co. Ltd., Nanjing, 210044
- Institute of SuperAccuracy Advanced Technology Co. Ltd., Hefei, 230088
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Huang X, Gu J, Li M, Yu X, Liu Y, Xu G. A Leakage Prediction Model for Sealing Performance Assessment of EPDM O-Rings under Irradiation Conditions. Polymers (Basel) 2023; 15:3073. [PMID: 37514462 PMCID: PMC10386121 DOI: 10.3390/polym15143073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 07/10/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023] Open
Abstract
In this work, a model for predicting the leakage rate was developed to investigate the effect of irradiation on the sealing performance of ethylene propylene diene monomer (EPDM) O-rings. The model is based on a mesoscopic interfacial gap flow simulation and accurately predicts the sealing performance of irradiated and non-irradiated materials by utilizing the gap height as an indicator in a mechanical simulation of the O-ring under operating conditions. A comparison with vacuum test results indicates that the model is a good predictor of leak initiation. The positive pressure leakage of the O-rings was investigated numerically. The results show the following. The sealing performance of the non-irradiated O-ring is much better than that of the irradiated one. The sealing performance is the worst at 0. 713 MGy and the best at 1.43 MGy, and the seal is maintained at an absorbed dose of 3.55 MGy. A theoretical analysis of the non-monotonic variation using the proposed model shows that the leakage behavior of the O-rings depends not only on the material properties but also on the roughness and prestressing properties. Finally, a method was proposed to classify the sealing performance, using the maximum allowable leakage rate as an indicator.
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Affiliation(s)
- Xiaoming Huang
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jimin Gu
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Ming Li
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xinli Yu
- China Nuclear Power Engineering Co., Ltd., No.117, Xisanhuanbeilu, Haidian District, Beijing 100840, China
| | - Yu Liu
- China Nuclear Power Engineering Co., Ltd., No.117, Xisanhuanbeilu, Haidian District, Beijing 100840, China
| | - Guoliang Xu
- School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
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Wang W, Liu H, Wu Z, Teng Y, Huang Y, Liu T, Yang H. A Comparison of Percutaneous Kyphoplasty with High-Viscosity and Low-Viscosity Bone Cement for Treatment of Osteoporotic Vertebral Compression Fractures: A Retrospective Study. Geriatr Orthop Surg Rehabil 2022; 13:21514593221119625. [PMID: 36090795 PMCID: PMC9459459 DOI: 10.1177/21514593221119625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 07/13/2022] [Accepted: 07/27/2022] [Indexed: 11/15/2022] Open
Abstract
Background Osteoporotic vertebral compression fracture (OVCF) has become a health issue
of worldwide concern. Percutaneous kyphoplasty (PKP) is one of the main
surgical methods for OVCFs. This study aimed to evaluate and compare the
clinical efficacy and safety of PKP with high- and low-viscosity bone cement
for OVCFs. Methods Totally 62 patients with single-level OVCF were enrolled in this study from
December 2018 to April 2021. Among them, 32 cases underwent PKP with
high-viscosity bone cement, while 30 cases underwent PKP with low-viscosity
bone cement. Visual analog scale (VAS) scores and Oswestry disability index
(ODI) scores were used in the pre- and post-operative period to assess
patients’ rehabilitation. Compression rates of anterior vertebra height
(AVH) and posterior vertebra height (PVH) were analyzed to evaluate the
restoration of vertebra height. Leakage rates and locations were recorded to
show clinical safety. Results VAS and ODI scores both significantly improved in 2 groups at 1 day, 1 month,
and 3 months after surgery. Compression rates of AVH and PVH at 1 day and
3 months after PKP were lower than those before surgery. However, there was
no significant difference in VAS scores, ODI scores, and compression rates
between both groups. However, PKP with high-viscosity bone cement achieved a
lower bone cement leakage rate significantly, which showed the safety of
high-viscosity bone cement in PKP. Conclusions PKP with high- and low-viscosity bone cement both improved the recovery of
patients and restored vertebra heights. Notably, PKP with high-viscosity
bone cement can achieve favorable clinical outcomes as well as lower bone
cement leakage rate.
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Affiliation(s)
- Wenhao Wang
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Hao Liu
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhikai Wu
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yun Teng
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yixue Huang
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Tao Liu
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Huilin Yang
- Department of Orthopaedics, The First Affiliated Hospital of Soochow University, Suzhou, China
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Hassan AK, Moinuddin M. Beamforming Using Exact Evaluation of Leakage and Ergodic Capacity of MU-MIMO System. Sensors (Basel) 2021; 21:6792. [PMID: 34696007 DOI: 10.3390/s21206792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 09/28/2021] [Accepted: 10/08/2021] [Indexed: 12/03/2022]
Abstract
Closed-form evaluation of key performance indicators (KPIs) of telecommunication networks help perform mathematical analysis under several network configurations. This paper deals with a recent mathematical approach of indefinite quadratic forms to propose simple albeit exact closed-form expressions of the expectation of two significant logarithmic functions. These functions formulate KPIs which include the ergodic capacity and leakage rate of multi-user multiple-input multiple-output (MU-MIMO) systems in Rayleigh fading channels. Our closed-form expressions are generic in nature and they characterize several network configurations under statistical channel state information availability. As a demonstrative example of the proposed characterization, the derived expressions are used in the statistical transmit beamformer design in a broadcast MU-MIMO system to portray promising diversity gains using standalone or joint maximization techniques of the ergodic capacity and leakage rate. The results presented are validated by Monte Carlo simulations.
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Deng H, Yang Y, Tang X, Li Y, He F, Zhang Q, Huang Z, Yang Z, Yang W. Phase-Change Composites Composed of Silicone Rubber and Pa@SiO 2@PDA Double-Shelled Microcapsules with Low Leakage Rate and Improved Mechanical Strength. ACS Appl Mater Interfaces 2021; 13:39394-39403. [PMID: 34392674 DOI: 10.1021/acsami.1c10374] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A kind of silicone rubber (SR)/paraffin (Pa)@silicon dioxide (SiO2)@polydopamine (PDA) phase-change composite was prepared in this work. The double-shelled Pa@SiO2@PDA phase-change microcapsules were constructed by oxidative self-polymerization of dopamine (DA) in Tris-HCl buffer solution. The effect of the DA content on the properties of Pa@SiO2@PDA microcapsules and SR/Pa@SiO2@PDA composites was researched. Due to the protective effect of SiO2, PDA layer, and SR matrix, the SR/Pa@SiO2@PDA composites have good leak-proofing performance, and the leakage rate of SR/Pa@SiO2@PDA-2 is as low as 0.45%. Phase-change enthalpies of the Pa@SiO2@PDA microcapsules and SR/Pa@SiO2@PDA composites are reduced slightly with increasing DA content. Meanwhile, the composites displayed improved mechanical strength. The tensile strength of SR/Pa@SiO2@PDA-2 can be up to 0.560 MPa, which is 1.85 times higher than the tensile strength of pure SR/Pa@SiO2 because the interface compatibility between Pa@SiO2 microcapsules and SR is improved through hydrogen bonding between the abundant groups on the PDA surface and the matrix. Moreover, the rough surface of the PDA-modified microcapsules also enhances the interface interaction through physical "interlocking". The new kind of SR/Pa@SiO2@PDA composite can be used for thermal management.
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Affiliation(s)
- Hao Deng
- State Key Laboratory of Environmental-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
| | - Yunmiao Yang
- State Key Laboratory of Environmental-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
- School of Economics and Management, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
| | - Xiaohong Tang
- School of Economics and Management, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
| | - Yongsheng Li
- State Key Laboratory of Environmental-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
| | - Fangfang He
- State Key Laboratory of Environmental-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
| | - Quanping Zhang
- State Key Laboratory of Environmental-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
| | - Zhong Huang
- Institute of Chemical Material, China Academy of Engineering Physics, Mianyang, Sichuan 621900, China
| | - Zhijian Yang
- Institute of Chemical Material, China Academy of Engineering Physics, Mianyang, Sichuan 621900, China
| | - Wenbin Yang
- State Key Laboratory of Environmental-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China
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Shi Y, Yu J. Wolbachia infection enhancing and decaying domains in mosquito population based on discrete models. J Biol Dyn 2020; 14:679-695. [PMID: 32783512 DOI: 10.1080/17513758.2020.1805035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
In this article, we formulate and study a discrete equation model depicting the pattern of Wolbachia infection in a mosquito population. A domain in [Formula: see text] is called a Wolbachia infection enhancing (or decaying) domain if in which the Wolbachia infection frequency of the next generation is always bigger (or smaller) than that of the current generation. We first give a complete analysis of the equivalent Wolbachia infection frequency curves. And then we clearly characterize the Wolbachia infection enhancing domain and decaying domain for all of the parameters, respectively. Finally, some numerical examples are also provided to illustrate our theoretical results.
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Affiliation(s)
- Yantao Shi
- Center for Applied Mathematics, Guangzhou University, Guangzhou, People's Republic of China
| | - Jianshe Yu
- Center for Applied Mathematics, Guangzhou University, Guangzhou, People's Republic of China
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Guarnieri G, Tecame M, Izzo R, Vassallo P, Sardaro A, Iasiello F, Cavaliere C, Muto M. Vertebroplasty Using Calcium Triglyceride Bone Cement (Kryptonite™) for Vertebral Compression Fractures. A Single-Centre Preliminary Study of Outcomes at One-Year Follow-up. Interv Neuroradiol 2014; 20:576-82. [PMID: 25363260 DOI: 10.15274/inr-2014-10060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 04/12/2014] [Indexed: 11/12/2022] Open
Abstract
This study assessed the one-year clinical and radiographic outcomes, in terms of pain-relief, vertebral re-fracture and complications, after vertebroplasty (VP) using a new osteoconductive cement (calcium triglyceride bone cement - Kryptonite™ bone cement, Doctors Research Group Inc., Southbury, CT, USA) to treat osteoporotic vertebral compression fractures. Sixteen consecutive osteoporotic patients (12 women and four men, mean age 68+/-10.5) were treated with VP using Kryptonite™ bone cement for a total of 20 vertebral fractures. All the patients complained of a pain syndrome resistant to medical therapy and all procedures were performed under fluoroscopy control with neuroleptoanalgesia using a monopedicular approach in 12 patients and bipedicular approach in four patients. All patients were studied by MR and MDCT and were evaluated with the visual analogue scale (VAS) and the Oswestry disability index (ODI) before treatment and at one and 12 months after the procedure. A successful outcome was observed in 80% of patients, with a complete resolution of pain. Differences in pre and post treatment VAS and ODI at one-year follow-up were significant (P<0.0001). We observed a disk and venous leakage in 66% of patients but only in one case did an asymptomatic pulmonary embolism occur during cement injection. Two cases of vertebral re-fractures at distant metamers were observed during follow-up. VP using Kryptonite bone cement is a helpful procedure that allows complete and long-lasting resolution of painful vertebral symptoms. The cost of the material is very high and the rate of disk and venous leakage is too high compared to standard cement.
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Affiliation(s)
| | - Mario Tecame
- Radiology Service, Seconda Università degli Studi di Napoli SUN; Naples, Italy
| | - Roberto Izzo
- Neuroradiology Service, Cardarelli Hospital; Naples, Italy
| | | | - Angela Sardaro
- Radiology Service, Seconda Università degli Studi di Napoli SUN; Naples, Italy
| | - Francesca Iasiello
- Radiology Service, Seconda Università degli Studi di Napoli SUN; Naples, Italy
| | | | - Mario Muto
- Neuroradiology Service, Cardarelli Hospital; Naples, Italy
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