PORTABLE SYNCHROTRON LIGHT SOURCES AND ADVANCED APPLICATIONS: 2nd International Symposium on Portable Synchrotron Light Sources and Advanced Applications
902(2007); http://dx.doi.org/10.1063/1.2723610View Description Hide Description
SSLS offers facilities for micro/nanofabrication and the analytical characterization of devices, materials and processes. Selected applications are presented including the manufacturing of electromagnetic metamaterials for the THz spectral range up to the near infrared, core‐hole clock spectroscopy of the charge transfer from BBB and BFF molecules to an Au electrode, and the characterization of Co and ITO thin films.
902(2007); http://dx.doi.org/10.1063/1.2723611View Description Hide Description
The SR center has been actively used in Ritsumeikan University for synchrotron radiation basic researches, education and training of graduate students and industrial applications for more than ten years. Present status of the storage ring and some recent activities are introduced. Future prospects are also addressed.
902(2007); http://dx.doi.org/10.1063/1.2723612View Description Hide Description
MIRRORCLE is a tabletop/portable synchrotron light source. It generates 10 mW order far infrared, watt order EUV/soft X‐ray, and brilliant hard X‐rays in 10 to 1000 keV range. MIRRORCLE is also a synchrotron that can generate directly monochromatic X‐ray beam. MIRRORCLE is a medical diagnostics system similar to a X‐ray tube radiology, but is very different in its fine spatial resolution and coherence of X‐ray. A difference in the material density instead of in the atomic number is distinguished by the phase contrast method, due to its highly coherent beam. MIRRORCLE is a non‐destructive testing system for more than 10cm thick heavy constructions with 10‐μm order fine spatial resolution. MIRRORCLE is an EUV lithography source, a laboratory size protein crystallography system, as well as a X‐ray microscope. We discuss advanced features of this multi‐functional light source MIRRORCLE.
902(2007); http://dx.doi.org/10.1063/1.2723613View Description Hide Description
We are developing the portable synchrotron MIRRORCLE‐CV series, which provides a high quality x‐ray beam for high precision non‐destructive testing (NDT). Computer simulations for the magnetic field design and electron dynamics reveal that the outer diameter of the synchrotron magnet can be as small as 30 cm. This synchrotron size approaches that of a conventional x‐ray tube.
902(2007); http://dx.doi.org/10.1063/1.2723614View Description Hide Description
The tabletop synchrotron MIRRORCLE‐20 has been optimized as an FIR beam source for the life science research. To collect the radiation from whole arc of the orbit, there is a magic mirror and a circular mirror installed within MIRRORCLE‐20. There is an FT‐IR and a cooled silicon bolometer for FIR. According to the specification of MIRRORCLE‐20, the e‐beam current is 100mA, the pulse width is 0.1msec, the peak storage current is 3A and the repetition is 100Hz. The power of MIR (wavelength shorter than 50μm) measured by thermopile is about 59mW and that of FIR (wavelength longer than 50μm) estimated by theoretical spectrum is about 8.5mW.
902(2007); http://dx.doi.org/10.1063/1.2723615View Description Hide Description
We are developing a laboratory‐scale protein structure analysis beamline based on our portable synchrotron MIRRORCLE‐20SX, which is a 20 MeV machine. Using the crystal as a target in the central orbit of the synchrotron, we will obtain parametric X‐ray, the spatially resolved monochromatic X‐ray. Our final goal is a development of protein crystallography basis cooperated with the protein group of the Nagahama Institute of Bio‐science and Technology, which performs screening, crystallization, and protein structure analysis. The METI Kansai funded this program.
Hard X‐Ray Phase‐Contrast Imaging for Medical Applications — Physicist’s Dream or Radiologist’s Mainstream?902(2007); http://dx.doi.org/10.1063/1.2723616View Description Hide Description
We briefly review currently practiced methods of X‐ray phase contrast imaging and consider some of their relative features, especially in regard to applicability to clinical medical studies. Various related technological issues and promising future areas of development are also briefly discussed.
902(2007); http://dx.doi.org/10.1063/1.2723617View Description Hide Description
Increasing rate of breast cancer in Japan is enormous in these years. Nevertheless only 2–3 % of female may receive mammography. In order to improve this number for early detection of breast cancer we have started development of a refraction‐based visualization of breast cancer. This system comprises two types of imaging: one is for a regular annual or biyearly check of the breast cancer. This is a 2‐D mode x‐ray dark‐field imaging where a Laue transmission type of angle analyzer with thickness of 2.124 mm is used for the FOV of 90 mm × 90 mm that can provide the spatial resolution better than 50 microns; the other a 3‐D reconstruction for further detailed check to specify type and location of breast cancer.
902(2007); http://dx.doi.org/10.1063/1.2723618View Description Hide Description
The portable synchrotron “MIRRORCLE‐6X” provides hard x‐rays with high brightness and wide energy spectrum ranging from 10–300 keV, emitted from a micron‐sized source, with wide divergence of ± 85 mrad. Correspondingly, images obtained using the “MIRRORCLE‐6X” showed significantly improved characteristics compared to conventional x‐ray tube images, namely, improved refraction contrast, high resolution, and high magnification. Thus, the “MIRRORCLE‐6X” is considered to be a novel medical imaging source.
A magnified image of a chest phantom, wherein a urethane ball of 8 mm diameter was implanted as an imitation of a cancer, was obtained. The detector used was an imaging‐plate (Fujifilm imaging plate, FCR ST‐IV) with 150 μm pixel size. The phantom and the detector were respectively set at 50 cm and 540 cm from the x‐ray source, so that the magnification was 10.8x. The x‐ray source was a Cu 25 μm rod. The resolution was about 25 μm. Images with such high resolution and magnification cannot be obtained by conventional x‐ray tubes with a source size of mm order. We can see the edges of costae and of the urethane ball at the back of the costae by the refraction contrast effect. Furthermore, we also see blood vessels surrounding the urethane ball. White spots, which are cross sections of blood vessels, were also observed. Therefore, observations of the shape of a cancer without surgical resection should be possible, and accurate diagnosis can be given using the “MIRRORCLE‐6X”.
902(2007); http://dx.doi.org/10.1063/1.2723619View Description Hide Description
As the first step on utilization of X‐ray microscope to tumor diagnosis at sub‐cellular level, we have started investigating intracellular localization of heavy metal marker in cancer cells. We calculated the image contrast and photon density for platinum and gold of 100 nm thickness in the protein at various X‐ray energies. At hard X‐ray region, phase contrast gave effective contrast to image heavy metal marker localization in the cancer cell of 10μm thickness. Minimum incident photons on the specimen were calculated as about 1011 photons/mm2. Combined with a suitable tumor marker and a high brilliant X‐ray compact source. X‐ray microscopy has capability to be in use as a tumor diagnosis tool with high special resolution.
902(2007); http://dx.doi.org/10.1063/1.2723620View Description Hide Description
The technique of computed tomography (CT) has been used in various fields, such as medical, non‐destructive testing (NDT), baggage checking, etc. A 3D‐CT system based on the portable synchrotron “MIRRORCLE”‐series will be a novel instrument for these fields. The hard x‐rays generated from the “MIRRORCLE” have a wide energy spectrum. Light and thin materials create absorption and refraction contrast in x‐ray images by the lower energy component (< 60 keV), and heavy and thick materials create absorption contrast by the higher energy component. In addition, images with higher resolutions can be obtained using “MIRRORCLE” with a small source size of micron order. Thus, high resolution 3D‐CT images of specimens containing both light and heavy materials can be obtained using “MIRRORCLE” and a 2D‐detector with a wide dynamic range. In this paper, the development and output of a 3D‐CT system using the “MIRRORCLE‐6X” and a flat panel detector are reported.
A 3D image of a piece of concrete was obtained. The detector was a flat panel detector (VARIAN, PAXSCAN2520) with 254 μm pixel size. The object and the detector were set at 50 cm and 250 cm respectively from the x‐ray source, so that the magnification was 5x. The x‐ray source was a 50 μm Pt rod. The rotation stage and the detector were remote‐controlled using a computer, which was originally created using LabView and Visual Basic software. The exposure time was about 20 minutes. The reconstruction calculation was based on the Feldkamp algorithm, and the pixel size was 50 μm. We could observe sub‐mm holes and density differences in the object. Thus, the “MIRRORCLE‐CV” with 1MeV electron energy, which has same x‐ray generation principles, will be an excellent x‐ray source for medical diagnostics and NDT.
902(2007); http://dx.doi.org/10.1063/1.2723621View Description Hide Description
Owing to its continuous energy distribution and strong output, synchrotron radiation is a powerful tool to study spectroscopic nature and photochemical reaction of biomolecules. Here we report recent achievement in our trial to examine the chemical evolution of amino acids induced by ultraviolet light and soft X‐ray in universe.
Using Far‐Infrared Spectroscopy as a Means of Probing Collective Fluctuations in Biological Molecules902(2007); http://dx.doi.org/10.1063/1.2723622View Description Hide Description
Far infrared Spectroscopy is a useful tool for probing the low frequency (picosecond) collective fluctuations in biological systems. If one considers that a chemical reaction in a cell takes place on a time scale of several hundred femtoseconds to a few picoseconds, it becomes clear that an understanding of the motion and relaxation mechanisms of the various biological molecules in the intracellular matrix on a similar time scale (corresponding to a frequency range of ∼10 – 200 cm−1) is essential in fully comprehending the underlying mechanisms defining cellular activity.
Both experimental and theoretical studies have indicated that both secondary structural changes and environmental conditions play an important role in determining reaction rates in both proteins and DNA. Therefore, the main focus of the talk will be to contrast the (intermolecular) collective fluctuations detected in the far‐infrared spectra of both protein and DNA systems, which are correlated with intermediate conformational states along the reaction pathway, with (intramolecular) changes observed in the secondary structure of the individual residues in these same systems with mid‐infrared spectroscopy.
Thermo‐Sensitive Receptor Protein: Role of TRPVs in Control of Body Temperature under Heat Radiation902(2007); http://dx.doi.org/10.1063/1.2723623View Description Hide Description
In vertebrate peripheral nervous system, skin heating and cooling are detected by thermo‐sensitive neurons tuned to respond over distinct temperature ranges. TRP‐family is thermo‐sensitive receptor protein which is Ca2+‐permeable ion channels expressing in cellular membrane. TRPV1 is activated by noxious heat above 42 °C, whereas TRPV3 and TRPV4 are sensitive to moderate temperatures (<34 °C). Although the amino acid sequence and the channel properties have been characterized, the molecular mechanism of temperature sensation remains poorly understood. In environment, mid and far infrared radiation act as physical stimuli. Here we examined the role of TRPV1 and TRPV4 in regulation of body temperature (BT) by using infrared laser as mild heat stimuli. In wild type mouse, the laser irradiation which caused the increase in skin temperature up to 55 °C did not induce the change in BT without any treatment of TRPVs. However, desensitization of TRPV1 with capsaicin resulted in the increase in BT by laser irradiation. On the other hand, in TRPV4‐knockout mouse, moderate thermal stimulus (skin surface temperature <43 °C) caused the increase in the BT. These results suggest that the processing of noxious and moderate thermal radiation stimuli may depend on the TRPV1 and TRPV4, respectively.
902(2007); http://dx.doi.org/10.1063/1.2723624View Description Hide Description
The infrared‐terahertz beamline at UVSOR‐II has been upgraded in 2004 for covering very low energy region below 0.3 THz (= 10 cm−). At the beamline, several characteristic experiments in the terahertz region are performed. Two examples of such experiments, reflectivity measurements at low temperatures and at high pressures are reported.
902(2007); http://dx.doi.org/10.1063/1.2723625View Description Hide Description
Recent electrical resistivity measurements under high pressure revealed that materials with strongly correlated electrons exhibit many interesting physical properties such as a stabilization of insulating phase, generation of unconventional superconductivity, and so on. However, there seems to be no attempt by optical measurements to study directly the change in the electronic states from metallic phase to insulating one under high pressure in GPa range because of the difficulty in experiments in the far‐infrared region. The difficulty is mainly caused by the insufficiency in the brightness of conventional black body sources. SPring‐8 supplies a more collimated and brilliant infrared beam to the end station than conventional thermal sources, and then make possible a spectromicroscopic measurement under high pressures above 10 GPa in the far‐infrared region. In this paper, we report recent results of the optical study on several kinds of solids which exhibit a cross‐over change in the electronic states under high pressure.
902(2007); http://dx.doi.org/10.1063/1.2723626View Description Hide Description
Far infrared vibrational Spectroscopy for distilled water was performed by Fourier Transform Infrared Spectroscopy (FT‐IR) in the FTIR beam line of MIRRORCLE 20. Synchrotron radiation was utilized as a light source for the absorption Spectroscopy in the frequency range from 100cm−1 to 20cm−1. Off‐line measurements by black body radiation of ceramic heater were also examined in the range from 400cm−1 to 50cm−1. Wide range spectrum was obtained after the SR data merged the off‐line data. We report the recent development in the beam line and the examples of spectra related to the water structure.
902(2007); http://dx.doi.org/10.1063/1.2723627View Description Hide Description
902(2007); http://dx.doi.org/10.1063/1.2723628View Description Hide Description
Terahertz region one‐dimensional photonic crystal (THz 1D‐PC) structures made of organic polymer were fabricated by simple stacking of thin films of different materials alternatively and investigated their optical properties by THz time‐domain spectroscopy. By this stacking method, one can fabricate hybrid structure made of organic and inorganic materials, which are not usually compatible.