• Journal of Ecology and Environment
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• v.31 no.2
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• pp.89-95
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• 2008

Sensing the approach of a predator is critical to the survival of prey, especially when the prey has no choice but to escape at a precisely timed moment. Escape behavior has been approached from both proximate and ultimate perspectives. On the proximate level, empirical research about electrophysiological mechanisms for detecting predators has focused on vision, an important modality that helps prey to sense approaching danger. Studies of looming-sensitive neurons in locusts are a good example of how the selective sensitivity of nervous systems towards specific targets, especially approaching objects, has been understood and realistically modeled in software and robotic systems. On the ultimate level, general optimality models have provided an evolutionary framework by considering costs and benefits of visually elicited escape responses. A recent paper showed how neural network models can be used to understand the evolution of visually mediated antipredatory behaviors. We discuss this new trend towards integration of these relatively disparate approaches, the proximate and the ultimate perspectives, for understanding of the evolution of behavior of predators and prey. Focusing on one of the best-studied escape pathway models, the Orthopteran LGMD/DCMD pathway, we discuss how ultimate-level optimality modeling can be integrated with proximate-level studies of escape behaviors in animals.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1324-1327
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• 2001

Radiation is a common treatment modality for central nervous system neoplasms. However, secondary tumor development must be considered in the differential diagnosis in patients with new or recurring symptoms after treatment with conventional radiotherapy. A 28-year-old woman developed a cavernous hemangioma about 9 years after brain irradiation for astrocytoma. Clinical and histopathological details are presented, and previous reports of radiation-induced intracranial cavernous hemangioma are reviewed.

• Journal of Biomedical Engineering Research
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• v.33 no.1
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• pp.32-38
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• 2012

Recently, several ultrasound imaging techniques for tissue characterization have been developed. Among them, ultrasound elastography is regarded as the most promising modality and has been rapidly developed. One of ultrasound elastography techniques is shear modulus imaging. Normal and cancerous tissues show big difference of shear moduli and they have good image contrast. However shear wave elastography requires more complicated hardware and more computations for image reconstruction algorithm. Therefore new efficient techniques are being developed. In this paper, we have developed a very flexible ultrasound system for elastography experiments. The developed system has capabilities to acquire ultrasound RF data of all channels and generate arbitrary ultrasound pulse sequences. It has a huge amount of memories for RF data acquisition and a simple and flexible pulse generator. We have verified the performance of the system showing conventional B-mode images and preliminary results of elastography. The developed system will be used to verify our own reconstruction algorithm and to develop more efficient elastography techniques.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.2051-2054
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• 2015

Background: Radiation therapy is a key part of the combined modality treatment for Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL), which can achieve locoregional control of disease. The 3D-conformal radiation oncology can be extended-field (EFRT), involved-field (IFRT) and involved node (INRT). New techniques have resulted in a smaller radiation field and lower dose for critical organs such as lung heart and breast. Materials and Methods: In our research, we made a virtual simulation for one patient who was treated in four different radiotherapeutic techniques: mantle field (MFRT), EFRT, IFRT and INRT. After delineatiion we compared dose-volume histograms for each technique. The fusion of CT for planning radiotherapy with the initial PET/CT was made using Softver Xio 4.6 in the Focal program. The dose for all four techniques was 36Gy. Results: Our results support the use of PET/CT in radiation therapy planning. With IFRT and INRT, the burden on the organs at risk is less than with MFRT and EFRT. On the other hand, the dose distribution in the target volume is much better with the latter. Conclusions: The aim of modern radiotherapy of HL and NHL is to reduce the intensity of treatment and therefore PET/CT should be used to reduce and not increase the amount of tissue receiving radiation.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.4
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• pp.83-90
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• 2017

Electrical impedance tomography is a relatively new nondestructive imaging modality in which the internal conductivity distribution is reconstructed based on the injected currents and measured voltages through electrodes placed on the surface of a domain. In this paper, a fast iterative Gauss-Newton method is proposed to increase the spatial resolution as well as reduce the inverse computational time in the inverse problem, which could be applied to online binary mixture flow applications. To evaluate the reconstruction performance of the proposed method, numerical experiments have been carried out and the results are analyzed.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2535-2537
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• 2016

Background: Most of the cervical cancer patients, including those with cervical adenocarcinomas, come at advanced stage in the developing world so its mortality is high. Radiotherapy is one of the treatment modality for advanced stage cervical adenocarcinomas, but its efficacy depends on several prognostic factors such as the stage, histopathology, presence of organ dysfunction and expression of cellular biology markers mainly involve in cell proliferation such as the epidermal growth factor receptor (EGFR). Some research indicates that activation of EGFR in malignancy (including cervical cancer) correlates with aggressive behavior, a poor prognosis and decreasing sensitivity of radiotherapy. However, the combination between targeted therapies and radiotherapy are innovative approaches which may provide a good result. This study aimed to assess any correlation between expression of EGFR and response to radiotherapy in cervical adenocarcinoma cases. Materials and Methods: A total of 32 women were registered in a retrospective study period January 2007 and May 2014. Paraffin blocks from these patients were processed by classical histological techniques and for immunohistochemical staining of EGFR, scoring being accomplished according to the immunoreactive scoring (IRS) of Remmele and Stegner. Results: Among the studied molecular factors, there was significant correlation expression of EGFR with poor response to radiotherapy (p=0.0001). Conclusions: The result of this study showed a significant correlation between expression of EGFR and sensitivity of radiation in cervical adenocarcinoma cases. Further research is necessary to obtain information about new therapeutic management.

• Imaging Science in Dentistry
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• v.50 no.1
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• pp.73-79
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• 2020

Computed tomography (CT) and magnetic resonance imaging (MRI) can be useful for the evaluation of palatal lesions, and strain elastography (performed together with intraoral ultrasonography) is a relatively new sonographic imaging modality. This report describes 2 clinical cases in which strain elastography was used to assess palatal tumors in conjunction with intraoral ultrasonography, CT, and MRI. In the first case, diagnosed as a myoepithelioma, the strain was determined to be 0.000% (strain of normal tissue, 0.556%). In the second case, diagnosed as an adenoid cystic carcinoma, the determined strain was 0.000% (strain of normal tissue, 1.077%). Therefore, we conclude that intraoral strain elastography can be useful for evaluating palatal lesions.

• East Asian Economic Review
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• v.20 no.2
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• pp.129-168
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• 2016

The Asia-Pacific region is not typically seen as one geographic or socio-economic space. Yet, 58 regional economies occupying the space of 28 million square kilometers from Turkey in the West, Russian Federation in the North, French Polynesia in the East and New Zealand in the South belong to the Economic and Social Commission of Asia and the Pacific (ESCAP). This commission provides a forum for member states that "promotes regional cooperation and collective action, assisting countries in building and sustaining shared economic growth and social equity". In 2013, ESCAP's members adopted the Bangkok Declaration to enhance efforts towards deeper regional economic integration. Yet this document neither proposes a concrete modality or modalities of achieving deeper integration, nor provides a sense of distance of individual countries to a "perceived" integrated Asia-Pacific.This paper aims to comprehensively quantify recent integration efforts of economies in the Asia-Pacific region. We provide an "index of integration effort" based on twelve metrics that measure the relative distance of a given economy to the region as an economic entity. Generally, we find that while the region has trended towards becoming integrated in general, both the level of integration and integration effort are inconsistent among Asia-Pacific economies. We discuss potential applications and extensions of the index in developing our perspective of the region's economic and social dynamics.

• The Korean Journal of Pain
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• v.19 no.1
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• pp.51-55
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• 2006

Background: A cervical transforaminal steroid injection is an effective therapeutic modality for radiculopathy of a herniated cervical disc or a cervical foraminal stenosis. However, there is some debate regarding the safety of the transforaminal approach under C-arm guidance compared with the posterior interlaminar approach. We report a new technique for cervical transforaminal steroid injection guided by MDCT. Methods: Patients presenting with radiating pain on their shoulder or arm were diagnosed using CT or MRI of a cervical herniated disc or a foraminal stenosis. Each patient whose symptoms were compatible with the image scan was enrolled in this study. They received a cervical transforaminal steroid injection under CT guidance, and the effectiveness and complications of this technique were evaluated over a 2-month period. Results: According to the CT scan, none of the participants had an internal jugular vein or a carotid artery invasion during the procedure. No vertebral artery injection was noted, and no patient developed a hematoma after the injection. The VAS score had improved significantly by 2, 4 and 8 weeks after the injection. Conclusions: While a conventional C-arm guided cervical transforaminal steroid injection does not appear to differentiate between the major vessels and structures in images, a CT guided approach is a more useful and safer technique for the precise placement of a needle.

• Journal of Biomedical Engineering Research
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• v.30 no.4
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• pp.279-287
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• 2009

Magnetic resonance electrical impedance tomography (MREIT) is a new medical imaging modality providing cross-sectional images of a conductivity distribution inside an electrically conducting object. MREIT has rapidly progressed in its theory, algorithm and experimental technique and now reached the stage of in vivo animal and human experiments. Conductivity image reconstructions in MREIT require various steps of carefully implemented numerical computations. To facilitate MREIT research, there is a pressing need for an MREIT software package with an efficient user interface. In this paper, we present an example of such a software, called CoReHA which stands for conductivity reconstructor using harmonic algorithms. It offers various computational tools including preprocessing of MREIT data, identification of boundary geometry, electrode modeling, meshing and implementation of the finite element method. Conductivity image reconstruction methods based on the harmonic $B_z$ algorithm are used to produce cross-sectional conductivity images. After summarizing basics of MREIT theory and experimental method, we describe technical details of each data processing task for conductivity image reconstructions. We pay attention to pitfalls and cautions in their numerical implementations. The presented software will be useful to researchers in the field of MREIT for simulation as well as experimental studies.