Vacuum Ultraviolet and Ultraviolet Spectroscopy of Tb³⁺- and Eu³⁺-Doped Na(Sr,Ba)PO₄Phosphate

Huang, Yanlin,Cao, Yonggang,Jiang, Chuanfang,Shi, Liang,Tao, Ye,Seo, Hyo Jin IOP Publishing 2008 Japanese journal of applied physics Vol.47 No.r8

Genomic Sequence Analysis and Organization of BmKαTx11 and BmKαTx15 from Buthus martensii Karsch: Molecular Evolution of α-toxin genes

Xu, Xiuling,Cao, Zhijian,Sheng, Jiqun,Wu, Wenlan,Luo, Feng,Sha, Yonggang,Mao, Xin,Liu, Hui,Jiang, Dahe,Li, Wenxin Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.4

Based on the reported cDNA sequences of $BmK{\alpha}Txs$, the genes encoding toxin $BmK{\alpha}Tx11$ and $BmK{\alpha}Tx15$ were amplified by PCR from the Chinese scorpion Buthus martensii Karsch genomic DNA employing synthetic oligonucleotides. Sequences analysis of nucleotide showed that an intron about 500 bp length interrupts signal peptide coding regions of $BmK{\alpha}Tx11$ and $BmK{\alpha}Tx15$. Using cDNA sequence of $BmK{\alpha}Tx11$ as probe, southern hybridization of BmK genome total DNA was performed. The result indicates that $BmK{\alpha}Tx11$ is multicopy genes or belongs to multiple gene family with high homology genes. The similarity of $BmK{\alpha}$-toxin gene sequences and southern hybridization revealed the evolution trace of $BmK{\alpha}$-toxins: $BmK{\alpha}$-toxin genes evolve from a common progenitor, and the genes diversity is associated with a process of locus duplication and gene divergence.

Visual Tracking with Online Incremental Deep Learning and Particle Filter

Shuai Cheng,Yonggang Cao,Junxi Sun,Guangwen Liu 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.12

To solve the problem of tracking the trajectory of a moving object and learning a deep compact image representation in the complex environment, a novel robust incremental deep learning tracker is presented under the particle filter framework. The incremental deep classification neural network was composed of stacked denoising autoencoder, incremental feature learning and support vector machine to achieve the feature-extracting and classification of particle set. Deep learning is successfully taken to express the image representations obtained effectively. Unsupervised feature learning is used to learn generic image features and transfer learning transforms knowledge from offline training to the online tracking process. The incremental feature learning was consisted of adding features and merging features to online learn compact feature set. Linear support vector machine increases the discretion for target with similar appearance and is further tuned to adapt to appearance changes of the moving object. Compared with the state-of-the-art trackers in the complex environment, the results of experiments on variant challenging image sequences show that incremental deep learning tracker solves the problem of existent trackers more efficiently, it has better robust and more accurate, especially for occlusions, background clutter, illumination changes and appearance changes.

Genomic Sequence Analysis and Organization of BmKαTx11 and BmKαTx15from Buthus martensii Karsch: Molecular Evolution of α-toxin genes

XiuLing Xu,Feng Luo,WenXin Li,ZhiJian Cao,JiQun Sheng,WenLan Wu,YongGang Sha,Xin Mao,Hui Liu,DaHe Jiang 한국생화학분자생물학회 2005 BMB Reports Vol.38 No.4

압전고분자 초음파 트랜스듀서와 생의학적 응용

하강렬(Kang-Lyeol Ha),曹永剛(Yonggang Cao) 한국비파괴검사학회 2012 한국비파괴검사학회지 Vol.32 No.5

PVDF와 P(VDF-TrFE)로 대별되는 압전고분자는 종래의 대표적인 압전재료인 PZT에 비해 전기음향변환효율이 떨어지며 내부손실이 큰 단점은 있으나, 음향임피던스가 물 또는 생체와 비슷하고 수신효율이 우수하며 광대역 특성을 나타내는 등의 장점을 가진 재료이다. 또한 다른 압전재료에 비해 얇은 막으로의 제작이 쉽고, 그 막은 유연하므로 복잡한 곡면을 갖는 고주파 초음파 트랜스듀서 재료로 유용하다. 그러한 특성은 생의학적 응용에 적합한바, 다양한 형태의 초음파 트랜스듀서가 연구 개발되어져 왔다. 본 논문에서는 먼저, 압전고분자막을 이용하여 초음파 트랜스듀서를 설계 제작하는데 있어서 고려해야할 몇 가지 주요사항을 기술하고, KLM 모델을 사용한 해석을 통하여 그 고려사항들이 트랜스듀서의 동작에 미치는 영향을 파악하였다. 다음으로, 의학적 또는 생물학적 응용을 목적으로 초음파 영상을 얻고 있는 몇몇 주요 응용분야에서 사용되는 압전고분자 트랜스듀서의 구조와 그것을 이용하여 얻은 영상의 특징에 대하여 간략히 해설하였다. PVDF(poly vinylidene fluoride) and P(VDF-TrFE)(poly vinylidene fluoride-tetrafluoroethylene) are the typical piezoelectric polymers with unique properties. Even they are inferior to conventional piezoelectric ceramics PZT in electromechanical conversion efficiency and interior loss, though they are superior in receiving sensitivity and frequency bandwidth. Their acoustic impedances are relatively close to water or biological tissue and it is easier to make thin film than other piezoelectric materials. Futhermore, the film is so flexible that it is easy to attach on a complex surface. Those properties are suitable for the ultrasound transducers which are useful for medical and biological application, so that various types of polymer transducers have been developed. In this paper, several important considerations for design and fabrication of piezoelectric polymer transducers were described and their effect on the transducer performance were demonstrated through the KLM model analysis. Then, it was briefly reviewed about the structures of the polymer transducers developed for obtaining images as well as the characteristics of the images in several important medical and biological application fields.

Effect of Iliac Vein Stent with Crown on Flow Field of Bifurcation

WenYing,Haiquan Feng,Xiaoqiang Li,Xiaotian Wang,Ping Cao,Yonggang Wang 한국유체기계학회 2020 International journal of fluid machinery and syste Vol.13 No.2

Interference in blood flow at bifurcation after stent implantation is one of the important causes of thrombosis. Therefore, it is necessary to research the effects of stent structure and implantation position on hemodynamics. Computational fluid dynamics and experimental comparative research methods were used to analyze the influence of stent structure and position of stent on exit velocity, pressure difference between inlet and outlet, higher and lower wall shear stress areas and contralateral flow field. It is indicated in the research that the effect of iliac vein stent implantation on the flow velocity and pressure distribution at the outlet is not obvious, but stent implantation has an influence on the proportion of low wall shear stress and high wall shear stress area in the iliac vein. The low wall shear stress area is inversely proportional to the height of the stent. After stent is implanted, proportion of the high wall shear stress area will decrease, but the degree of decline is not obvious. As the height of stent is increased, the disturbing effect of stent on contralateral blood flow becomes more pronounced. In addition, it is confirmed by the experiments in vitro and in vivo that stent with crown would effectively reduce the interference to the contralateral flow field and the risk of thrombosis and restenosis. Finite element analysis provides effective theoretical support for studying the influence of iliac vein stent implantation on blood flow field.

초음파에 의한 온도상승 가시화용 생체 모의매질

정지희,김정순,하강렬,김무준,Jung, Ji-Hee,Kim, Jung-Soon,Ha, Kang-Lyeol,Kim, Moo-Joon,Cao, Yonggang 한국음향학회 2014 韓國音響學會誌 Vol.33 No.5

초음파에 의한 온도상승효과를 조사하기 위한 생체 모의매질을 제안하였다. 생체와 유사한 음향특성을 가지며 내부온도분포의 관찰이 가능한 투명도를 확보하기 위하여 카라기난(carrageenan) 젤을 선택하였다. 매질 내부의 온도상승효과를 가시화 하기 위하여 온도에 따라 변색되는 시온필름을 사용하였으며 카라기난의 농도 및 첨가제로 사용한 수크로스(sucrose)의 농도에 따른 생체 모의매질의 음향특성을 조사하였다. 그 결과, 카라기난 및 수크로스의 농도를 조절함으로써 음향감쇠계수를 0.44~0.49 dB/cm/MHz의 범위에서 제어할 수 있었으며 음향임피던스의 경우 1.52~1.77 Mrayls의 범위에서 제어가능함을 확인했다. 제안된 생체 모의매질은 첨가제 및 카라기난의 농도에 따라 생체조직에 대응되는 음향특성을 갖도록 제어할 수 있었으며 초음파에 의한 매질내부의 온도상승 관찰이 가능하였다. 제안된 모의매질을 이용하여 평면 및 집속 초음파에 의한 온도상승효과를 비침습적으로 가시화하여 확인함으로써 본 제안법의 유효성을 검증하였다. To probe the temperature elevation effect caused by ultrasound, a tissue mimicking phantom was newly suggested. A carrageenan gel was adopted to realize not only the required transparency for visualization but also acoustic characteristics similar to human tissue. To visualize the temperature elevation inside phantom, thermochromic film with a critical temperature of discoloration was introduced. Acoustic characteristics of the tissue mimicking phantom were examined when the concentrations of carrageenan and sucrose changed. As the results, the attenuation coefficient of the phantom could be controlled in the range of 0.44~0.49 dB/cm/MHz, and the acoustic impedance in the range of 1.52~1.77 Mrayls. We could control the acoustic characteristics of the phantom by different concentration of carrageenan and sucrose, and it was possible to examine the temperature elevation caused by ultrasound in the phantom. The suggested method was verified by noninvasively visualizing the temperature elevation due to planar and focused ultrasound using the fabricated phantom.