Simulation Platform of Multi-Pulse Photoacoustic Microscopy Based on K-Space Pseudospectral Method

Photoacoustic imaging has emerged in the past decades. Compared with the traditional medical imaging mode, it has better imaging performance and has great development potential in the field of biological imaging. In traditional photoacoustic microscopy, a single laser pulse is generally used to irradiate the sample to produce photoacoustic signal. And sig-nal-to-noise ratio (SNR) is a very important indicator for photoacoustic im-aging. In order to obtain the image with high SNR, multiple acquisition or increasing laser pulse energy is usually adopted. The former will lead to slower imaging speed, and the latter will lead to photobleaching or pho-totoxicity. Here, we propose multi-pulse photoacoustic microscopy, the photoacoustic signals were stimulated sequentially using multiple laser pulses in each A line data acquisition. In order to verify the feasibility of this method, a multi-pulse photoacoustic imaging simulation platform is established using k-Wave toolbox. The performance of multi-pulse photo-acoustic imaging is verified through the three scanning modes of photoa-coustic microscopy A-scan, B-scan, and C-scan. The results indicate that the SNR is proportion to the number of laser pulses used, high SNR can be achieved by low-energy laser pulse. This work will help to expand the ap-plication of photoacoustic imaging.

Bessel-Beam Photoacoustic Microscopical Simulation Platform Based on k-Wave

We developed a Bessel-beam photoacoustic microscopical simulation platform by using the k-Wave: MATLAB toolbox. The simulation platform uses the ring slit method to generate Bessel beam. By controlling the inner and outer radius of the ring slit, the depth-of-field (DoF) of Bessel beam can be controlled. And the large volumetric image is obtained by point scanning. The simulation experiments on blood vessels were carried out to demonstrate the feasibility of the simulation platform. This simulation work can be used as an auxiliary tool for the research of Bessel-beam photoacoustic microscopy.

Globalization, Women, and Poverty： A Transcultural Reading of Sheng Keyi＇s Northern Girls

China＇s rise within a global economy has had diverse consequences for Chinese women. For the super rich and the rising middle class, it has offered opportunities for vast wealth. For the newly emergent underclass of migrant workers who have flooded to the cities, it has engendered exploitative states of vulnerability, especially for rural women. In this paper we locate our inquiry in the context of globalization and its impact on rural women＇s lives as witnessed through the medium of a unique and distinctive women＇s life narrative, Sheng Keyi＇s Bei mei （Northern Girls）. The text testifies to the underside of women＇s lives within the new market economy, documenting the cruelty of global capitalism. It presents an alternative version of the history of China＇s rise in the global economy and maps a trajectory of increasing inequality from a previously silenced female perspective. Sheng Keyi＇s world speaks to the sordid world of women, the world of yin. It coexists with the dizzying ascent of the yang--as the powerful nation grapples with social inequality and fragmentation. In its international circulation, Northern Girls opens readers to the contradictions and ambivalent aspects of China＇s economic rise and its consequences specifically for migrant women.

澳大利亚焦虑症话语下的中国

中国对于当今澳大利亚的贸易关系、资本流动、教育以及全球秩序等方面都具有重要的意义。然而,澳大利亚关于中国的公共话语却陷入两种舆论的相互冲突之中:一种舆论是关于两国经济互补性的,另一种就是关于"恐惧"和"焦虑"。中国的发展导致澳大利亚社会出现了两种不同的反应:一种认为中国的经济壮大"标志着其加入资本主义的世界体系"而应受到鼓励,而另一种则认为中国的发展是一种"威胁",需要加以防控。本文探讨的就是这样一个矛盾的话题,可称之为"中国焦虑症"(Changst)。作者们认为正是由于按照发展主义的逻辑(Chakrabarty,2000)和运用西方资本主义和欧洲中心主义历史的同质化而误读了中国。这种误读认为中国发展只能复制西方的资本主义模式,但是中国独特的资本流动形式打乱了西方的发展逻辑,因而导致焦虑。同样,这种话语认为中国社会及其教育体系处在准现代化时代,大批中国学生留学海外又让人"恐惧"其文化受到"污染"。本文通过六个澳大利亚的案例分析来探讨这种焦虑情绪,揭示中国与澳大利亚的交往如何产生了强烈而毫无根据的焦虑。