2020
2020
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Record 457 of
Title:Bioinspired surface hierarchical microstructures of Ti6Al4V alloy with a positive effect on osteoconduction
Author(s):Li, Chen(1); Yang, Lijun(1); Liu, Nan(1); Yang, Yong(2); Zhao, Jing(3); Yang, Pengfei(4); Cheng, Guanghua(5)Source: Surface and Coatings Technology Volume: 388 Issue: DOI: 10.1016/j.surfcoat.2020.125594 Published: 25 April 2020Abstract:Osteoconduction is critical for the success of dental and orthopaedic implants. Inspired by the remarkable adhesion of the skin structures in tree frog toe pads, biomimetic hierarchical surface structures on titanium alloy implants are fabricated by laser surface texturing and chemistry surface treatment in this work, to improve osteoconduction on implants. The main differences in the wettability, bioactivity in simulated body fluid and osteoblastic cell MC3T3 proliferation were measured and analyzed among Ti6Al4V samples with smooth surface, micro-hexagons and hierarchical structures, respectively. Noteworthy, bioinspired hierarchical structures displayed the lowest contact angle in hydrophilicity, best bioactivity and excellent cell proliferation. The reasons for these differences were found and discussed in the topographical cues and bioactive surface layer. An innovative functionalization strategy of improving the osteoconduction on titanium alloy implants was proposed using the hierarchical structures, which is meaningful in various tissue engineering applications and implant fields. ? 2020 Elsevier B.V.Accession Number: 20201108286212 -
Record 458 of
Title:Using Cherenkov imaging to monitor the match line between photon and electron radiation therapy fields on biological tissue phantoms
Author(s):Li, Yi(1,2,3); Liu, Hongjun(1,4); Huang, Nan(1); Wang, Zhaolu(1); Zhang, Chunmin(2)Source: Journal of Biomedical Optics Volume: 25 Issue: 12 DOI: 10.1117/1.JBO.25.12.125001 Published: December 1, 2020Abstract:Significance: Due to patients' respiratory movement or involuntary body movements during breast cancer radiotherapy, the mismatched adjacent fields in surface exposure regions could result in insufficient dosage or overdose in these regions, which would lead to tissue injury, excessive skin burns, and potential death. Cherenkov luminescence imaging (CLI) could be used to effectively detect the matching information of adjacent radiation fields without extra radiation or invasive imaging. Aim: Our objective was to provide a biological experimental basis for monitoring matching of adjacent radiation fields between photon and electron fields due to introduced shifts during radiotherapy by CLI technique. Approach: A medical accelerator was used to generate photon and electron fields. An industrial camera system was adopted to image the excited CLI signal during irradiation of chicken tissue with yellow (group A and group C experiments) or black color (group B experiment). The following introduced shifts were tested: 10, 5, 2, and 0 mm toward superior or inferior direction. A model was introduced to deal with matching error analysis of adjacent radiation fields due to introduced shifts with adapted plans used to treat neoplasms of the right breast with supraclavicular nodes or internal mammary lymph node. Results: The matching values between photon and electron fields were consistent with the tested introduced shifts during yellow chicken irradiation. In group A, average discrepancies were 0.59 ± 0.35 mm and 0.68 ± 0.37 mm for photon fields and electron fields in anterior/posterior (AP) direction, with 87% and 75% of measurement within 1 mm, respectively. In group C, average discrepancies were 0.80 ± 0.65 mm and 1.07 ± 0.57 mm for oblique photon field with gantry angles of 330 deg and 150 deg, with 66% and 65% of measurement within 1 mm, respectively. The average discrepancies were 0.44 ± 0.30 mm for electron field in the AP direction, with 94% of measurement within 1 mm. The matching error introduced by the proposed method was less than 1.5 mm for AP fields and 2 mm for oblique incidence fields. However, the field matching could not be monitored with black chicken tissue irradiation due to a weak CLI signal that could hardly be extracted from background noise in group B. Conclusions: CLI is demonstrated for the quantitative monitoring of the field match line on light biological tissue phantoms and has potential for monitoring of field matching in surface tissue during breast cancer radiotherapy. ? The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its.Accession Number: 20210109729092 -
Record 459 of
Title:Generation of a noise-like pulse from an erbium-doped fiber laser based on nonlinear multimode interference
Author(s):Zhao, Fengyan(1); Li, Ning(3); Wang, Hushan(2)Source: Laser Physics Volume: 30 Issue: 12 DOI: 10.1088/1555-6611/abc06d Published: December 1, 2020Abstract:A noise-like pulse (NLP) is generated in an anomalous-dispersion passively mode-locked erbium-doped fiber laser using graded-index multimode fiber (GIMF) as the all-fiber saturable absorber (SA) for the first time. By splicing two sections of bending GIMF at both ends of a single mode fiber and optimizing the birefringence and nonlinear parameters, stable NLP mode-locking operation can be achieved within a wide pump power range. Meanwhile, the performances of NLP mode-locking have been analyzed experimentally by changing the length of the GIMF. ? 2020 Astro Ltd.Accession Number: 20204809560692 -
Record 460 of
Title:Design of a low noise area array CCD imaging system for exoplanet search
Author(s):Di, Lamei(1,2); Liu, Hong(1,2,3,4); Wei, Ruyi(1,2); Qiao, Nianzu(5); Chen, Shasha(1,2,4)Source: Journal of Imaging Science and Technology Volume: 64 Issue: 3 DOI: 10.2352/J.ImagingSci.Technol.2020.64.3.030504 Published: June 2020Abstract:The search for exoplanets is a focal topic in astronomy. Since the signal from the detected target is very weak, the imaging system needs to have ultra-low readout noise. Therefore, a low noise charge-coupled diode (CCD) imaging system for exoplanet search (LNCIS) is proposed. Based on the area array CCD (TH7888A), the circuit and timing drive of LNCIS are designed. Especially, the application of correlation dual sampling (CDS) and asynchronous first-in, first-out (FIFO) memory can effectively suppress the correlation noise of the image signal. Moreover, this article proposes a fully differential double correlation sampling method, which can achieve better sampling effect and can better eliminate common-mode noise, improve dynamic range, and achieve high-quality image signal output. In addition, an independent counting method for adjusting the exposure time is proposed, which satisfies the requirements of the long exposure time of the imaging system, so that the CCD can be provided an independent and adjustable exposure time in the photosensitive stage. The LNCIS uses the FPGA (ZYNQ7000) as the core control device to produce the timing according to the function of the system. Finally, the experimental results show that the real-time image acquisition is achieved under the condition that the CCD readout clock frequency is 20 MHz. It is verified that the circuit and timing drive of the imaging system can meet the design requirements. ? Society for Imaging Science and Technology 2020Accession Number: 20203709166939 -
Record 461 of
Title:Single-shot Fourier ptychographic microscopy via annular monochrome LED array
Author(s):Pan, An(1,2,3); Shen, Cheng(2); Yao, Baoli(1); Yang, Changhuei(2)Source: Frontiers in Optics - Proceedings Frontiers in Optics + Laser Science APS/DLS Volume: Issue: DOI: 10.1364/FIO.2019.FTh3F.4 Published: September 8, 2019Abstract:Single-shot Fourier ptychographic microscopy is realized by slightly defocusing with annular illumination. A 2× resolution quantitative phase map can be recovered by one-step deconvolution and further refined by iterative multiplexing algorithm. ? OSA 2019. The Author(s).Accession Number: 20202408830071 -
Record 462 of
Title:Research Progress of Mid-infrared Femtosecond Sources Based on Optical Parametric Amplification (Invited)
Author(s):Cao, Hua-Bao(1); Wang, Hu-Shan(1); Yuan, Hao(1,2); Liu, Xin(1,2); Huang, Pei(1); Wang, Yi-Shan(1); Zhao, Wei(1); Fu, Yu-Xi(1)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 49 Issue: 11 DOI: 10.3788/gzxb20204911.1149005 Published: November 2020Abstract:The tunable mid-infrared femtosecond sources with broadband, tunable wavelength, stable carrier envelope phase and high average power are achievable through optical parametric amplification. In this review, the key techniques of optical parametric ampification systems working in the mid-infrared range are introduced, including but not limited, broadband optical parametrical amplification and dispersion manging techniques. After that, the research progress and development prospect of the mid-infrared femtosecond source based on optical parametric amplification are presented and discussed. ? 2020, Science Press. All right reserved.Accession Number: 20205109633094 -
Record 463 of
Title:Femtosecond laser manipulating underoil surface wettability for water removal from oil
Author(s):Wu, Junrui(1); Yin, Kai(1,2); Li, Ming(3); Xiao, Si(1); Wu, Zhipeng(1); Wang, Kai(4); Duan, Ji-An(2); He, Jun(1)Source: Colloids and Surfaces A: Physicochemical and Engineering Aspects Volume: 601 Issue: DOI: 10.1016/j.colsurfa.2020.125030 Published: 20 September 2020Abstract:The oil containing a small amount of water droplets have induced serious operation malfunctions for precision industrial equipment and even brought fatal disasters, which have aroused widespread concern. However, developing an effective strategy for removal of water from oil is still an enormous challenge. Here, we present a rapid and facile method for fabricating underoil superhydrophilic surface by one-step femtosecond laser direct writing technology. Interestingly, two extreme underoil wettability statuses can be achieved through tuning the scanning velocity (V). Concretely, the pristine underoil hydrophobic titanium sheet will become underoil superhydrophilicity when V is 0.1 m/s, while it will exhibit underoil superhydrophobicity when V increases to 3 m/s. Moreover, the underoil superhydrophilic surface shows excellent water absorption, which could realize the purification of oil contains water droplets regardless of the oil types, and the corresponding mechanism is propounded. We believe that femtosecond laser micromachining has tremendous superiority in solving the problem of oil containing water droplets. ? 2020 Elsevier B.V.Accession Number: 20202208773273 -
Record 464 of
Title:Compact catadioptric optical system with long focal length large relative aperture and large field of view
Author(s):Shen, Yang(1); Wang, Hu(1); Xue, Yaoke(1); Xie, Yongjie(1); Lin, Shangmin(1); Liu, Jie(1); Liu, Meiying(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11570 Issue: DOI: 10.1117/12.2580275 Published: 2020Abstract:Nanosatellites usually refer to satellites with mass less than 10 kg and practical functions. With the development of high and new technology and the promotion of demand, nanosatellites play an important role in scientific research, national defense, commercial and other fields with the advantages of small size, low power consumption, short development cycle, formation networking and low cost to complete many complex space tasks. High resolution remote sensing is one of the important applications of microsatellites, because of its small size, it requires more for optical payload. According to the structural form of RC system, this paper presents a compact coaxial four reflection catadioptric system based on the structural form of RC system. The final optical system design results are as follows: The focal length is 192.2mm, the pupil diameter is 136mm (the effective pupil diameter is 105mm), the working band is 500-900nm, the imaging field of view is 4.5 °, and the total optical length is 58mm. The analysis shows that the transfer function of the optical system is higher than 0.45 at 100lp/mm, the distortion of the whole market is less than 0.12%, and the relative illuminance of the whole field of view is higher than 96%. It is proved that the optical system has good imaging quality in the full field of view, and the system has good compactness to meet the load requirements of micro nanosatellite. ? 2020 SPIE. All rights reserved.Accession Number: 20204909580487 -
Record 465 of
Title:Versatile multipartite Einstein-Podolsky-Rosen steering via a quantum frequency comb
Author(s):Cai, Yin(1,2); Xiang, Yu(3,4,5); Liu, Yang(1,6,7); He, Qiongyi(3,4,5); Treps, Nicolas(2)Source: Physical Review Research Volume: 2 Issue: 3 DOI: 10.1103/PhysRevResearch.2.032046 Published: August 2020Abstract:Multipartite Einstein-Podolsky-Rosen steering is an essential resource for quantum communication networks where the reliability of the equipment at all of the nodes cannot be fully trusted. Here, we present the experimental generation of a highly versatile and flexible repository of multipartite steering using an optical frequency comb and ultrafast pulse shaping. Simply modulating the optical spectral resolution of the detection system using the pulse shaper, this scheme is able to produce on-demand four-, eight-, and 16-mode Gaussian steering without changing the photonics architecture. We find that the steerability increases with a higher spectral resolution. For the 16-mode state, we identify as many as 65 534 possible steering bipartitions existing in this intrinsic multimode quantum resource, and demonstrate that the prepared state steerability is robust to mode losses. Moreover, we verify four types of monogamy relations of Gaussian steering and demonstrate the constraint imposed by one of them to be strongly lifted. Our method offers a powerful foundation for constructing quantum networks in real-world scenarios. ? 2020 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.Accession Number: 20204309384392 -
Record 466 of
Title:Highly sensitive label-free biosensor based on graphene-oxide functionalized micro-tapered long period fiber grating
Author(s):Wang, Ruiduo(1,2); Ren, Zhaoyu(3); Kong, Depeng(1); Hu, Baowen(1); He, Zhengquan(1)Source: Optical Materials Volume: 109 Issue: DOI: 10.1016/j.optmat.2020.110253 Published: November 2020Abstract:An accurate and highly sensitive label-free biosensing platform for human hemoglobin detection was demonstrated. The biosensor was derived from a micro-tapered long period fiber grating (MTLPG) functionalized by graphene oxide (GO) nanosheets. When the hemoglobin molecules are absorbed onto the fiber surface, the resonance wavelength shift, and thus the hemoglobin concentration can be detected. With hemoglobin concentration from 0.0 mg/mL to 2.0 mg/mL in deionized water, urea solution as well as glucose solution, the GO-MTLPG was implemented as a biosensor and achieved sensitivity of ?2 nm/(mg/mL), ?1.03 nm/(mg/mL) and ?0.73 nm/(mg/mL), respectively. Moreover, the minimum limit of detection is 0.02 mg/mL, which is far below the hemoglobin threshold value of anemia that recommended by World Health Organization. In addition, the reusability of GO-MTLPG for hemoglobin detection in various interfering compounds were validated. The proposed GO-MTLPG can be developed as an optical sensor applied in biomedical and biochemical fields. ? 2020 Elsevier B.V.Accession Number: 20203209011640 -
Record 467 of
Title:Supervised Dimensionality Reduction Methods via Recursive Regression
Author(s):Liu, Yun(1); Zhang, Rui(2); Nie, Feiping(3); Li, Xuelong(3); Ding, Chris(1)Source: IEEE Transactions on Neural Networks and Learning Systems Volume: 31 Issue: 9 DOI: 10.1109/TNNLS.2019.2940088 Published: September 2020Abstract:In this article, the recursive problems of both orthogonal linear discriminant analysis (OLDA) and orthogonal least squares regression (OLSR) are investigated. Different from other works, the associated recursive problems are addressed via a novel recursive regression method, which achieves the dimensionality reduction in the orthogonal complement space heuristically. As for the OLDA, an efficient method is developed to obtain the associated optimal subspace, which is closely related to the orthonormal basis of the optimal solution to the ridge regression. As for the OLSR, the scalable subspace is introduced to build up an original OLSR with optimal scaling (OS). Through further relaxing the proposed problem into a convex parameterized orthogonal quadratic problem, an effective approach is derived, such that not only the optimal subspace can be achieved but also the OS could be obtained automatically. Accordingly, two supervised dimensionality reduction methods are proposed via obtaining the heuristic solutions to the recursive problems of the OLDA and the OLSR. ? 2012 IEEE.Accession Number: 20203809203003 -
Record 468 of
Title:Modeling and Rotating Speed Control of the Sun-Tracking System with Flexible Solar Arrays
Author(s):Wang, Meng(1); Li, Xin(1); Wang, Chen(1)Source: Chinese Control Conference, CCC Volume: 2020-July Issue: DOI: 10.23919/CCC50068.2020.9188879 Published: July 2020Abstract:The rotating speed fluctuation of the flexible solar array in the process of tracking the sun will affect the accuracy of the solar array pointing to the sun and the safety of the spacecraft in orbit. In this paper, the flexible solar array and its drive mechanism are modeled as a whole. According to the characteristics of the dynamic model, this paper proposes a sliding mode control method (SMC) to control the rotating speed of the sun-tracking system with flexible solar arrays. The simulation results show that the SMC method can effectively reduce the rotating speed fluctuation of the system. ? 2020 Technical Committee on Control Theory, Chinese Association of Automation.Accession Number: 20203909242622