SiGe-based broadband and high suppression frequency doubler ICs for wireless communications

制度:新 ; 報告番号:甲3419号 ; 学位の種類:博士(工学) ; 授与年月日:2011/9/15 ; 早大学位記番号:新574

Radionuclide-Based Cancer Imaging Targeting the Carcinoembryonic Antigen

Carcinoembryonic antigen (CEA), highly expressed in many cancer types, is an important target for cancer diagnosis and therapy. Radionuclide-based imaging techniques (gamma camera, single photon emission computed tomography [SPECT] and positron emission tomography [PET]) have been extensively explored for CEA-targeted cancer imaging both preclinically and clinically. Briefly, these studies can be divided into three major categories: antibody-based, antibody fragment-based and pretargeted imaging. Radiolabeled anti-CEA antibodies, reported the earliest among the three categories, typically gave suboptimal tumor contrast due to the prolonged circulation life time of intact antibodies. Subsequently, a number of engineered anti-CEA antibody fragments (e.g. Fab’, scFv, minibody, diabody and scFv-Fc) have been labeled with a variety of radioisotopes for CEA imaging, many of which have entered clinical investigation. CEA-Scan (a 99mTc-labeled anti-CEA Fab’ fragment) has already been approved by the United States Food and Drug Administration for cancer imaging. Meanwhile, pretargeting strategies have also been developed for CEA imaging which can give much better tumor contrast than the other two methods, if the system is designed properly. In this review article, we will summarize the current state-of-the-art of radionuclide-based cancer imaging targeting CEA. Generally, isotopes with short half-lives (e.g. 18F and 99mTc) are more suitable for labeling small engineered antibody fragments while the isotopes with longer half-lives (e.g. 123I and 111In) are needed for antibody labeling to match its relatively long circulation half-life. With further improvement in tumor targeting efficacy and radiolabeling strategies, novel CEA-targeted agents may play an important role in cancer patient management, paving the way to “personalized medicine”

Anatomical and molecular imaging of skin cancer

Skin cancer is the most common form of cancer types. It is generally divided into two categories: melanoma (∼ 5%) and nonmelanoma (∼ 95%), which can be further categorized into basal cell carcinoma, squamous cell carcinoma, and some rare skin cancer types. Biopsy is still the gold standard for skin cancer evaluation in the clinic. Various anatomical imaging techniques have been used to evaluate different types of skin cancer lesions, including laser scanning confocal microscopy, optical coherence tomography, high-frequency ultrasound, terahertz pulsed imaging, magnetic resonance imaging, and some other recently developed techniques such as photoacoustic microscopy. However, anatomical imaging alone may not be sufficient in guiding skin cancer diagnosis and therapy. Over the last decade, various molecular imaging techniques (in particular single photon emission computed tomography and positron emission tomography) have been investigated for skin cancer imaging. The pathways or molecular targets that have been studied include glucose metabolism, integrin αvβ3, melanocortin-1 receptor, high molecular weight melanoma-associated antigen, and several other molecular markers. Preclinical molecular imaging is thriving all over the world, while clinical molecular imaging has not lived up to the expectations because of slow bench-to-bedside translation. It is likely that this situation will change in the near future and molecular imaging will truly play an important role in personalized medicine of melanoma patients

Investigation of relaxation factor in landweber iterative algorithm for electrical capacitance tomography

It is crucial to select a suitable relaxation factor in iterative image reconstruction algorithms (e.g. Landweber iterative algorithm) for electrical capacitance tomography (ECT) because it affects the convergence. By simulation, it is found notably that the relaxation factor should be selected adaptively according to the sensor structure (e.g. the number of electrodes) and the permittivity distribution in capacitance measurements. With different number of electrodes and four typical permittivity distributions, the relaxation factor and the related convergence are investigated in consideration of the change in relative image error. It is shown that the relaxation factor can be chosen based on the upper boundary of all relaxation factors. The conclusions in this paper can be used for practical industrial processes, regarding the adaptive selection of relaxation factor and the number of iterations needed

Research on Effects of Incidence to Turbine Guide Cascade Aerodynamic Performance

When steam turbine set runs, the changes of incidence angle could cause the change of the flow loss in the cascade passages. It was necessary to research the flow performance in steam turbine passages by changing incidence angle. With the help of hydrodynamic software CFX, we could conduct numerical simulations at three incidence angles of 20°, 0°, and -20°, respectively. The computation results indicated that the blades with aft-loading profile had a good adaptation to the incidence angle. After changing incidence angle, the incidence angle affected the distribution of static surface pressure less within most of the scope of pressure surface and suction surface than other location. However, incidence angle −20° would decrease pressure loss within a narrow range, and incidence angle 20° would increase pressure loss