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What will the future hold for artificial organs in the service of assisted reproduction: prospects and

Mara Simopoulou, Konstantinos Sfakianoudis, Petroula Tsioulou, Anna Rapani, Polina Giannelou, Nikolaos Kiriakopoulos, Agni Pantou, Nikolaos Vlahos, George Anifandis, Stamatis Bolaris, Konstantinos Pantos, Michael Koutsilieris

《医学前沿（英文）》 2019年 第13卷 第6期   页码 627-638 doi: 10.1007/s11684-019-0697-5

摘要： Assisted reproduction provides a wide spectrum of treatments and strategies addressing infertility. However, distinct groups of infertile patients with unexplained infertility, congenital disorders, and other complex cases pose a challenge in fertilization (IVF) practices. This special cohort of patients is associated with futile attempts, IVF overuse, and dead ends in management. Cutting edge research on animal models introduced this concept, along with the development of artificial organs with the aim to mimic the respective physiological functions in reproduction. Extrapolation on clinical application leads to the future use of infertility management in humans. To date, the successful clinical application of artificial reproductive organs in humans is not feasible because further animal model studies are required prior to clinical trials. The application of these artificial organs could provide a solution to infertility cases with no other options. This manuscript presents an overview on the current status, future prospects, and considerations on the potential clinical application of artificial ovary, uterus, and gametes in humans. This paper presents how the IVF practice landscape may be shaped and challenged in the future, along with the subsequent concerns in assisted reproductive treatments.

关键词： artificial ovary     artificial uterus     artificial gametes     assisted reproduction     considerations     in vitro fertilization    

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Estimation of reproduction numbers of COVID-19 in typical countries and epidemic trends under different

Chen Xu, Yinqiao Dong, Xiaoyue Yu, Huwen Wang, Lhakpa Tsamlag, Shuxian Zhang, Ruijie Chang, Zezhou Wang, Yuelin Yu, Rusi Long, Ying Wang, Gang Xu, Tian Shen, Suping Wang, Xinxin Zhang, Hui Wang, Yong Cai

《医学前沿（英文）》 2020年 第14卷 第5期   页码 613-622 doi: 10.1007/s11684-020-0787-4

摘要： The coronavirus disease 2019 (COVID-19) has become a life-threatening pandemic. The epidemic trends in different countries vary considerably due to different policy-making and resources mobilization. We calculated basic reproduction number (R ) and the time-varying estimate of the effective reproductive number (R ) of COVID-19 by using the maximum likelihood method and the sequential Bayesian method, respectively. European and North American countries possessed higher R and unsteady R fluctuations, whereas some heavily affected Asian countries showed relatively low R and declining R now. The numbers of patients in Africa and Latin America are still low, but the potential risk of huge outbreaks cannot be ignored. Three scenarios were then simulated, generating distinct outcomes by using SEIR (susceptible, exposed, infectious, and removed) model. First, evidence-based prompt responses yield lower transmission rate followed by decreasing R . Second, implementation of effective control policies at a relatively late stage, in spite of huge casualties at early phase, can still achieve containment and mitigation. Third, wisely taking advantage of the time-window for developing countries in Africa and Latin America to adopt adequate measures can save more people’s life. Our mathematical modeling provides evidence for international communities to develop sound design of containment and mitigation policies for COVID-19.

关键词： reproduction number     SEIR model     COVID-19     estimate    

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Development of lunar regolith composite and structure via laser-assisted sintering

《机械工程前沿（英文）》 doi: 10.1007/s11465-021-0662-2

摘要： Aiming at the exploration and resource utilization activities on the Moon, in situ resource utilization and in situ manufacturing are proposed to minimize the dependence on the ground transportation supplies. In this paper, a laser-assisted additive manufacturing process is developed to fabricate lunar regolith composites with PA12/SiO2 mixing powders. The process parameters and composite material compositions are optimized in an appropriate range through orthogonal experiments to establish the relationship of process–structure–property for lunar regolith composites. The optimal combination of composite material compositions and process parameters are mixing ratio of 50/50 in volume, laser power of 30 W, scanning speed of 3500 mm/s, and scanning hatch space of 0.2 mm. The maximum tensile strength of lunar regolith composites reaches 9.248 MPa, and the maximum depth of surface variation is 120.79 μm, which indicates poor powder fusion and sintering quality. Thereafter, the mechanical properties of laser-sintered lunar regolith composites are implemented to the topology optimization design of complex structures. The effectiveness and the feasibility of this laser-assisted process are potentially developed for future lightweight design and manufacturing of the solar panel installed on the lunar rover.

关键词： in situ manufacturing     laser-assisted powder fusion process     mechanical properties     topological structure design    

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Guidelines for navigation-assisted spine surgery

Bo Liu, Da He, Yajun Liu, Xiaoguang Han, Jingwei Zhao, Mingxing International Society for Computer Assisted

《医学前沿（英文）》 2020年 第14卷 第4期   页码 518-527 doi: 10.1007/s11684-020-0775-8

摘要： Spinal surgery is a technically demanding and challenging procedure because of the complicated anatomical structures of the spine and its proximity to several important tissues. Surgical landmarks and fluoroscopy have been used for pedicle screw insertion but are found to produce inaccuracies in placement. Improving the safety and accuracy of spinal surgery has increasingly become a clinical concern. Computer-assisted navigation is an extension and application of precision medicine in orthopaedic surgery and has significantly improved the accuracy of spinal surgery. However, no clinical guidelines have been published for this relatively new and fast-growing technique, thus potentially limiting its adoption. In accordance with the consensus of consultant specialists, literature reviews, and our local experience, these guidelines include the basic concepts of the navigation system, workflow of navigation-assisted spinal surgery, some common pitfalls, and recommended solutions. This work helps to standardize navigation-assisted spinal surgery, improve its clinical efficiency and precision, and shorten the clinical learning curve.

关键词： guidelines     spine surgery     computer-assisted navigation    

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Linking key intervention timings to rapid declining effective reproduction number to quantify lessons

Zhihang Peng, Wenyu Song, Zhongxing Ding, Quanquan Guan, Xu Yang, Qiaoqiao Xu, Xu Wang, Yankai Xia

《医学前沿（英文）》 2020年 第14卷 第5期   页码 623-629 doi: 10.1007/s11684-020-0788-3

摘要： Coronavirus disease 2019 (COVID-19) is currently under a global pandemic trend. The efficiency of containment measures and epidemic tendency of typical countries should be assessed. In this study, the efficiency of prevention and control measures in China, Italy, Iran, South Korea, and Japan was assessed, and the COVID-19 epidemic tendency among these countries was compared. Results showed that the effective reproduction number( ) in Wuhan, China increased almost exponentially, reaching a maximum of 3.98 before a lockdown and rapidly decreased to below 1 due to containment and mitigation strategies of the Chinese government. The in Italy declined at a slower pace than that in China after the implementation of prevention and control measures. The in Iran showed a certain decline after the establishment of a national epidemic control command, and an evident stationary phase occurred because the best window period for the prevention and control of the epidemic was missed. The epidemic in Japan and South Korea reoccurred several times with the fluctuating greatly. The epidemic has hardly rebounded in China due to the implementation of prevention and control strategies and the effective enforcement of policies. Other countries suffering from the epidemic could learn from the Chinese experience in containing COVID-19.

关键词： COVID-19     epidemic control comparison     Chinese experience    

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Medical applications of phytoestrogens from the Thai herb

null

《医学前沿（英文）》 2012年 第6卷 第1期   页码 8-21 doi: 10.1007/s11684-012-0184-8

摘要：

Pueraria mirifica Airy Shaw et Suvatabandhu is a medicinal plant endemic to Thailand. It has been used in Thai folklore medicine for its rejuvenating qualities in aged women and men for nearly one hundred years. Indeed, it has been claimed that P. mirifica contains active phytoestrogens (plant substances with estrogen-like activity). Using high performance liquid chromatography, at least 17 phytoestrogens, mainly isoflavones, have been isolated. Thus, fairly considerable scientific researches, both in vitro in cell lines and in vivo in various species of animals including humans, have been conducted to date to address its estrogenic activity on the reproductive organs, bones, cardiovascular diseases and other climacteric related symptoms. The antioxidative capacity and antiproliferative effect on tumor cell lines have also been assessed. In general, P. mirifica could be applicable for preventing, or as a therapeutic for, the symptoms related to estrogen deficiency in menopausal women as well as in andropausal men. However, the optimal doses for each desirable effect and the balance to avoid undesired side effects need to be calculated before use.

关键词： white Kwao Krua     miroestrol     estrogenic activity     reproduction     osteoporosis     breast cancer     Alzheimer    

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Energy field-assisted high-speed dry milling green machining technology for difficult-to-machine metal

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0744-9

摘要： Energy field-assisted machining technology has the potential to overcome the limitations of machining difficult-to-machine metal materials, such as poor machinability, low cutting efficiency, and high energy consumption. High-speed dry milling has emerged as a typical green processing technology due to its high processing efficiency and avoidance of cutting fluids. However, the lack of necessary cooling and lubrication in high-speed dry milling makes it difficult to meet the continuous milling requirements for difficult-to-machine metal materials. The introduction of advanced energy-field-assisted green processing technology can improve the machinability of such metallic materials and achieve efficient precision manufacturing, making it a focus of academic and industrial research. In this review, the characteristics and limitations of high-speed dry milling of difficult-to-machine metal materials, including titanium alloys, nickel-based alloys, and high-strength steel, are systematically explored. The laser energy field, ultrasonic energy field, and cryogenic minimum quantity lubrication energy fields are introduced. By analyzing the effects of changing the energy field and cutting parameters on tool wear, chip morphology, cutting force, temperature, and surface quality of the workpiece during milling, the superiority of energy-field-assisted milling of difficult-to-machine metal materials is demonstrated. Finally, the shortcomings and technical challenges of energy-field-assisted milling are summarized in detail, providing feasible ideas for realizing multi-energy field collaborative green machining of difficult-to-machine metal materials in the future.

关键词： difficult-to-machine metal material     green machining     high-speed dry milling     laser energy field-assisted milling     ultrasonic energy field-assisted milling     cryogenic minimum quantity lubrication energy field-assisted milling    

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Sub-nanometer finishing of polycrystalline tin by inductively coupled plasma-assisted cutting

《机械工程前沿（英文）》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0751-5

摘要： Polycrystalline tin is an ideal excitation material for extreme ultraviolet light sources. However, the existence of grain boundary (GB) limits the surface roughness of polycrystalline tin after single-point diamond turning (SPDT). In this work, a novel method termed inductively coupled plasma (ICP)-assisted cutting was developed for the sub-nanometer finishing of polycrystalline tin. The relationship between ICP power, processing time, and modification depth was established by thermodynamic simulation, and the fitted heat transfer coefficient of polycrystalline tin was 540 W/(m2·K). The effects of large-thermal-gradient ICP treatment on the microstructure of polycrystalline tin were studied. After 0.9 kW ICP processing for 3.0 s, corresponding to the temperature gradient of 0.30 K/µm, the grain size of polycrystalline tin was expanded from a size of approximately 20–80 μm to a millimeter scale. The Taguchi method was used to investigate the effects of rotational speed, depth of cut, and feed rate on SPDT. Experiments conducted based on the ICP system indicated that the plasma-assisted cutting method promoted the reduction of the influence of GB steps on the finishing of polycrystalline tin, thereby achieving a surface finish from 8.53 to 0.80 nm in Sa. The results of residual stress release demonstrated that the residual stress of plasma-assisted turning processing after 504 h stress release was 10.7 MPa, while that of the turning process without the ICP treatment was 41.6 MPa.

关键词： plasma-assisted cutting     polycrystalline tin     single-point diamond turning     surface roughness    

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Recent advances in ultrasonic-assisted machining for the fabrication of micro/nano-textured surfaces

Shaolin XU,Tsunemoto KURIYAGAWA,Keita SHIMADA,Masayoshi MIZUTANI

《机械工程前沿（英文）》 2017年 第12卷 第1期   页码 33-45 doi: 10.1007/s11465-017-0422-5

摘要：

In this paper, the state of art of ultrasonic-assisted machining technologies used for fabrication of micro/nano-textured surfaces is reviewed. Diamond machining is the most widely used method in industry for manufacturing precision parts. For fabrication of fine structures on surfaces, conventional diamond machining methods are competitive by considering the precision of structures, but have limitations at machinable structures and machining efficiency, which have been proved to be partly solved by the integration of ultrasonic vibration motion. In this paper, existing ultrasonic-assisted machining methods for fabricating fine surface structures are reviewed and classified, and a rotary ultrasonic texturing (RUT) technology is mainly introduced by presenting the construction of vibration spindles, the texturing principles, and the applications of textured surfaces. Some new ideas and experimental results are presented. Finally, the challenges in using the RUT method to fabricate micro/nano-textured surfaces are discussed with respect to texturing strategies, machinable structures, and tool wear.

关键词： ultrasonic-assisted machining     textured surface     micro/nano-structures     functional performance    

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Lobectomy by video-assisted thoracoscopic surgery (VATS) for early stage of non-small cell lung cancer

null

《医学前沿（英文）》 2011年 第5卷 第1期   页码 53-60 doi: 10.1007/s11684-011-0121-2

摘要：

Video-assisted thoracoscopic surgery (VATS) provides a new approach for treating early-stage lung cancer. Lobectomy by VATS has many advantages over conventional thoracotomy, such as shorter recovery time, less postoperative pain, and faster resumption of a normal lifestyle. However, there is still much debate on the role of VATS in lobectomy for the treatment of lung cancer. Concerns regarding safety, the extent of mediastinal lymph node dissection, and long-term survival have made some surgeons apprehensive of its validity for lung cancer. In this paper, we review the development of thoracoscopy, the present status of VATS for early stage of non-small cell lung cancer (NSCLC), and comparison between VATS and open thoracotomy in the management of NSCLC.

关键词： non-small cell lung cancer     video-assisted thoracoscopic surgery     lobectomy    

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Study on the microwave-assisted extraction of polyphenols from tea

Liyun WANG, Peiyong QIN, Yan HU,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 307-313 doi: 10.1007/s11705-009-0282-6

摘要： This study demonstrated a promising method for quickly extracting tea polyphenol (TP) by microwave-assisted extraction (MAE) technology. Some influential parameters, including MAE temperature, microwave power, concentration of extraction solvent, MAE time and the solid/liquid ratio, were investigated. The optimum condition of MAE was obtained by dual extraction with 60% ethanol (v/v) and the solid/liquid ratio 1:12 g/mL at 80°C for 10 minutes under the microwave power 600 W. The yield of TP was 96.5% under the described condition. Compared with traditional methods, including hot reflux extraction (HRE), ultrasound-assisted extraction (UAE) and supercritical fluid extraction (SFE), the extraction time was saved 8 times than that of HRE, and the yield was increased by 17.5%. The extraction time at comparable levels of production was saved 2 times, and the energy consumption was one fourth that of UAE. The extraction time was saved 5 times than that of SFE, and the yield of TP was increased by 40%. Moreover, compared with MAE of TP studied by others, it decreased the solid/liquid ratio from 1 ∶ 20 to 1 ∶ 12 g/mL without 90-min pre-leaching time, and the yield of TP was increased by 6%–40%.

关键词： energy consumption     microwave-assisted extraction     optimum condition     pre-leaching     concentration    

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Novel seed-assisted synthesis of indium tin oxide submicro-cubes and their resistivity

《化学科学与工程前沿（英文）》 2023年 第17卷 第5期   页码 557-569 doi: 10.1007/s11705-022-2249-9

摘要： Indium tin oxide films, an important n-type semiconductor oxide, show great prospects in optoelectronic device applications. Consequently, as a key raw material of targets for sputtering films, it is important to prepare low-resistivity indium tin oxide powders. Herein, low-resistivity indium tin oxide submicro-cubes are synthesized by a seed-assisted coprecipitation method. The effects of seed content, In3+ concentration, aging time, reaction temperature and calcination temperature on resistivity were investigated by single factor and orthogonal experiments. To ensure reliability and reproducibility of data, each experiment was repeated three times and resistivity of each sample was measured three times to obtain average value. The results indicated that optimal sample was matched with cubic phase In2O3. The single-crystal indium tin oxide particles exhibited a regular cubic shape with a size of nearly 500 nm and low resistivity of 0.814 Ω·cm. Compared with particles prepared by the conventional coprecipitation method, indium tin oxide submicro-cubes showed good dispersion. The presence of seed particles provided nucleation sites with lower energy barriers and promoted formation of submicro-cubes. The face-to-face contact among particles and good dispersion contributed to electron transfer, resulting in lower resistivity. The seed-assisted synthesis provides a novel way to prepare low-resistivity indium tin oxide submicro-cubes.

关键词： indium tin oxide     submicro-cubes     resistivity     seed-assisted coprecipitation method     orthogonal experiment    

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Recent progress in electric-field assisted combustion: a brief review

《能源前沿（英文）》 2022年 第16卷 第6期   页码 883-899 doi: 10.1007/s11708-021-0770-z

摘要： The control of combustion is a hot and classical topic. Among the combustion technologies, electric-field assisted combustion is an advanced techno-logy that enjoys major advantages such as fast response and low power consumption compared with thermal power. However, its fundamental principle and impacts on the flames are complicated due to the coupling between physics, chemistry, and electromagnetics. In the last two decades, tremendous efforts have been made to understand electric-field assisted combustion. New observations have been reported based on different combustion systems and improved diagnostics. The main impacts, including flame stabilization, emission reduction, and flame propagation, have been revealed by both simulative and experimental studies. These findings significantly facilitate the application of electric-field assisted combustion. This brief review is intended to provide a comprehensive overview of the recent progress of this combustion technology and further point out research opportunities worth investigation.

关键词： electric field     combustion     flame stabilization     emission reduction     flame propagation    

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Plasma-assisted oxidation of benzoic acid

Anna Khlyustova, Nikolay Sirotkin

《化学科学与工程前沿（英文）》 2020年 第14卷 第4期   页码 513-521 doi: 10.1007/s11705-019-1825-0

摘要： Plasma-assisted oxidation of organic compounds is one of the developing technologies for wastewater treatment. Plasmas effectively accelerate degradation processes due to plasma generated reactive species and ultra-violet radiation. Oxidation of benzoic acid in aqueous solutions by the atmospheric pressure glow discharge and underwater diaphragm discharge was studied and monitored by fluorescence and spectrophotometric methods. Discharge type and solution pH affect the formation rates of mono- and dihydroxybenzoic acids. Dihydroxyl derivatives were formed only by glow discharge action. The yields of hydroxyl radical were estimated on the kinetics data for the hydroxylation of benzoic acid. The steps of the hydroxylation processes and further oxidation were described.

关键词： atmospheric pressure glow discharge     underwater diaphragm discharge     oxidation     benzoic acid     hydroxyl radical    

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Machinability of ultrasonic vibration-assisted micro-grinding in biological bone using nanolubricant

《机械工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0717-z

摘要： Bone grinding is an essential and vital procedure in most surgical operations. Currently, the insufficient cooling capacity of dry grinding, poor visibility of drip irrigation surgery area, and large grinding force leading to high grinding temperature are the technical bottlenecks of micro-grinding. A new micro-grinding process called ultrasonic vibration-assisted nanoparticle jet mist cooling (U-NJMC) is innovatively proposed to solve the technical problem. It combines the advantages of ultrasonic vibration (UV) and nanoparticle jet mist cooling (NJMC). Notwithstanding, the combined effect of multi parameter collaborative of U-NJMC on cooling has not been investigated. The grinding force, friction coefficient, specific grinding energy, and grinding temperature under dry, drip irrigation, UV, minimum quantity lubrication (MQL), NJMC, and U-NJMC micro-grinding were compared and analyzed. Results showed that the minimum normal grinding force and tangential grinding force of U-NJMC micro-grinding were 1.39 and 0.32 N, which were 75.1% and 82.9% less than those in dry grinding, respectively. The minimum friction coefficient and specific grinding energy were achieved using U-NJMC. Compared with dry, drip, UV, MQL, and NJMC grinding, the friction coefficient of U-NJMC was decreased by 31.3%, 17.0%, 19.0%, 9.8%, and 12.5%, respectively, and the specific grinding energy was decreased by 83.0%, 72.7%, 77.8%, 52.3%, and 64.7%, respectively. Compared with UV or NJMC alone, the grinding temperature of U-NJMC was decreased by 33.5% and 10.0%, respectively. These results showed that U-NJMC provides a novel approach for clinical surgical micro-grinding of biological bone.

关键词： micro-grinding     biological bone     ultrasonic vibration (UV)     nanoparticle jet mist cooling (NJMC)     grinding force     grinding temperature    

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标题 作者 时间 类型 操作

What will the future hold for artificial organs in the service of assisted reproduction: prospects and

Mara Simopoulou, Konstantinos Sfakianoudis, Petroula Tsioulou, Anna Rapani, Polina Giannelou, Nikolaos Kiriakopoulos, Agni Pantou, Nikolaos Vlahos, George Anifandis, Stamatis Bolaris, Konstantinos Pantos, Michael Koutsilieris

期刊论文

Estimation of reproduction numbers of COVID-19 in typical countries and epidemic trends under different

Chen Xu, Yinqiao Dong, Xiaoyue Yu, Huwen Wang, Lhakpa Tsamlag, Shuxian Zhang, Ruijie Chang, Zezhou Wang, Yuelin Yu, Rusi Long, Ying Wang, Gang Xu, Tian Shen, Suping Wang, Xinxin Zhang, Hui Wang, Yong Cai

期刊论文

Development of lunar regolith composite and structure via laser-assisted sintering

期刊论文

Guidelines for navigation-assisted spine surgery

Bo Liu, Da He, Yajun Liu, Xiaoguang Han, Jingwei Zhao, Mingxing International Society for Computer Assisted

期刊论文

Linking key intervention timings to rapid declining effective reproduction number to quantify lessons

Zhihang Peng, Wenyu Song, Zhongxing Ding, Quanquan Guan, Xu Yang, Qiaoqiao Xu, Xu Wang, Yankai Xia

期刊论文

Medical applications of phytoestrogens from the Thai herb

null

期刊论文

Energy field-assisted high-speed dry milling green machining technology for difficult-to-machine metal

期刊论文

Sub-nanometer finishing of polycrystalline tin by inductively coupled plasma-assisted cutting

期刊论文

Recent advances in ultrasonic-assisted machining for the fabrication of micro/nano-textured surfaces

Shaolin XU,Tsunemoto KURIYAGAWA,Keita SHIMADA,Masayoshi MIZUTANI

期刊论文

Lobectomy by video-assisted thoracoscopic surgery (VATS) for early stage of non-small cell lung cancer

null

期刊论文

Study on the microwave-assisted extraction of polyphenols from tea

Liyun WANG, Peiyong QIN, Yan HU,

期刊论文

Novel seed-assisted synthesis of indium tin oxide submicro-cubes and their resistivity

期刊论文

Recent progress in electric-field assisted combustion: a brief review

期刊论文

Plasma-assisted oxidation of benzoic acid

Anna Khlyustova, Nikolay Sirotkin

期刊论文

Machinability of ultrasonic vibration-assisted micro-grinding in biological bone using nanolubricant

期刊论文