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This letter develops a novel algorithm for lip motion analysis arising as a result of feeling amused after watching television comedy programs as emotion-eliciting stimuli. The analysis is based on measuring the variance of new lip motion features extracted from pronouncing some sentences after watching the stimuli. The results of the conducted experiment show that these features can serve as efficient indices for determining the occurrence of amusement feelings. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

The phase shift of forward-diffracted X-rays by a perfect crystal is discussed on the basis of the dynamical theory of X-ray diffraction. By means of a triple Laue-case X-ray interferometer, the phase shift of forward-diffracted X-rays by a silicon crystal in the Bragg geometry was investigated.

Biological soft tissues are almost transparent to hard X rays and therefore cannot be investigated without enhancement with a contrast medium, such as iodine. On the other hand, phase-contrast X-ray imaging is sensitive to light elements (1-8). This is because the X-ray phase shift cross section is almost thousand times larger than the X-ray absorption cross section for light elements such as hydrogen, carbon, nitrogen and oxygen (4,5). Hence, phase-contrast X-ray imaging is a promising technique for observing the structure inside biological soft tissues without the need for staining and without serious radiation exposure. We have devised a means of observing biological tissues in three dimensions using a novel X-ray computed tomography (CT) by modifying the phase-contrast technique. To generate appropriate CT input data, we used phase-mapping images obtained using an X-ray interferometer (6) and computer analysis of interference patterns (9). Now, we present a three-dimensional observation result of a nonstained sample of a cancerous rabbit liver, using a synchrotron X-ray source. Phase-contrast X-ray CT was able to clearly differentiate the cancer lesion from the normal tissue. Moreover, fine structures corresponding to cancerous degeneration and fibrous tissues were clearly depicted.

X-ray phase tomography with X-ray Talbot interferometry (XTI) is reported. XTI employs two transmission gratings and generates a contrast corresponding to the differential phase shift caused by a sample. Quantitative phase measurement and tomographic image reconstruction with XTI are demonstrated for biological samples. Finally, the possibility of medical applications of XTI is discussed, based on the advantage of XTI that divergent and polychromatic X-rays are available.

Micro-phase-contrast X-ray computed tomography with an X-ray interferometer (micro-phase-contrast CT) is in operation to obtain high spatial resolution images of less than 0.01 mm at the undulator beam-line 20XU of SPring-8, Japan, and we applied micro-phase-contrast CT to observe the organs of rats and hamsters. The excised kidney and spleen fixed by formalin were imaged. The fine inner-structures such as vessels, glomeruli of kidney and white and red pulps of spleen were visualized clearly about 0.01-mm spatial resolutions without using contrast agent or staining procedure. The results were very similar to those by optical microscopic images with 20-fold magnification. These results suggest that the micro-phase tomography might be a useful tool for various biomedical researches.

Phase‐contrast X‐ray imaging, including phase tomography, was performed at the medium‐length beamline BL20XU of SPring‐8, where undulator X rays were available at 245 m from the source point. A crystal X‐ray interferometer and an X‐ray Talbot interferometer with transmission gratings were used to perform different kinds of phase‐contrast imaging. The crystal X‐ray interferometer was devised in that a crystal lamella for beam recombination was thinned down to 40 μm to achieve high‐resolution imaging. A quick fringe‐scanning mechanism was also constructed enabling the phase measurement with a few second and therefore phase tomography with several minutes. The X‐ray Talbot interferometer was studied as a novel and simple method that generated a contrast corresponding to differential phase. Phase tomography was also attained with the X‐ray Talbot interferometer.

Phase tomography using diffraction‐enhanced imaging (DEI) is presented with the observation of a phantom consisting of polyvinyl‐chloride tubes and water. The boundary between the tube and water was successfully differentiated in a resultant tomographic image obtained with 0.06‐nm synchrotron X rays. The sensitivity of this method is discussed in comparison with an image obtained by conventional X‐ray tomography. The spatial and density resolutions achieved by the phase tomography are also discussed.

X‐ray Talbot Interferometry (XTI) is demonstrated as a novel and simple X‐ray phase‐sensitive imaging method. Differential phase contrast is generated with XTI and quantitative determination of the differential phase is attained in combination with a phase‐shifting technique, further enabling phase tomography. Because XTI does not use crystals but transmission gratings, divergent X‐rays with a broad energy band are available. This is an advantage for medical applications especially using a compact X‐ray source.

A novel three‐dimensional x‐ray imaging method has been developed by combining a phase‐contrast x‐ray imaging technique with x‐ray computed tomography. This phase‐contrast x‐ray computed tomography (PCX‐CT) provides sectional images of organic specimens that would produce absorption‐contrast x‐ray CT images with little contrast. Comparing PCX‐CT images of rat cerebellum and cancerous rabbit liver specimens with corresponding absorption‐contrast CT images shows that PCX‐CT is much more sensitive to the internal structure of organic specimens.

The effects of exercise on the metabolism of caffeine (CA) were studied 3 h after administration of the drug to race horses which then underwent exercise sets (1000-m gallop). Analysis was made of pharmacokinetics of CA, changes in its plasma concentrations, its metabolites, i.e., theophylline (TP), theobromine (TB) and paraxanthine (PX), and the molar concentration ratios of CA to these metabolites. After exercise, AUC and t1/2 tended to decrease, and the concentration of CA decreased, while the concentrations of TP and TB significantly increased. The TP/CA ratio and TB/CA ratio significantly increased from 6 to 74h and from 25 to 50h after drug administration, respectively. This indicated promotion of metabolism of CA into TP and TB. The effects on PX were minimal.

Background— Phase-contrast x-ray imaging using an x-ray interferometer has great potential to reveal the structures inside soft tissues, because the sensitivity of this method to hydrogen, carbon, nitrogen, and oxygen is ≈1000 times higher than that of the absorption-contrast x-ray method. Imaging of vessels is very important to understand the vascular distribution of organs and tumors, so the possibility of selective angiography based on phase contrast is examined with a physiological material composed of low-atomic-number elements. Methods and Results— Phase-contrast x-ray imaging was performed with a synchrotron x-ray source. Differences in refractive index, dδ, of physiological saline, lactated Ringer’s solution, 5% glucose, artificial blood such as pyridoxylated hemoglobin–polyoxyethylene conjugate, and perfluorotributylamine were measured. Because the dδ of physiological saline has highest contrast, it was used for the phase-contrast x-ray imaging of vessel, and this was compared with absorption-contrast x-ray images. Vessels >0.03 mm in diameter of excised liver from rats and a rabbit were revealed clearly in phase-contrast x-ray imaging, whereas the vessel could not be revealed at all by the absorption-contrast x-ray image. Absorption-contrast x-ray images with iodine microspheres depicted only portal veins >0.1 mm in diameter with nearly the same x-ray dose as the present phase-contrast x-ray imaging. Conclusions— Phase-contrast x-ray imaging explored clear depiction of the vessels using physiological saline with small doses of x-rays.

Phase-contrast x-ray imaging with x-ray interferometer can depict the minute difference within the biological object, and its sensitivity is about 1000 times higher than that of absorption-contrast method. For biomedical use of this technique, a large monolithic x-ray interferometer and 2 crystal interferometer having a field of view with 25 mm x 25 mm is being developed. Phase-contrast x-ray CT could reveal detail structures within tumor and surrounded tissue, and the vessel imaging of rat liver is also possible using physiological saline at 17.7 keV x-ray energy. Recently, human breast tissues were imaged at 35 keV and the contrast of image was much better than usual absorption contrast x-ray image obtained at 17.7 keV energy.

Image quality of phase-contrast x-ray computed tomogram was evaluated by comparing tomograms obtained by using triple Laue-case x-ray interferometers with a thin or a thick crystal wafer. It was confirmed that the spatial resolution was improved when the wafer is thinned. A simulation study by means of the Takagi-Taupin equation was also carried out for theoretical understanding. According to the wavefront modulation transfer function calculated for Laue-case diffraction, it is suggested that using an interferometer with al thin wafer tends to improve image quality. However, a new problem is pointed out that the accuracy in quantitative measurement of high-frequency phase modulation is not secured even when the wafer is thinned.

X-ray grating interferometry has been spotlighted in the last decade as a technique for X-ray phase imaging and tomography. In this paper, we report that this interferometry can also be applied to the real-space mapping of weak diffuse scattering (ultrasmall-angle X-ray scattering) in grazing incidence geometry. A preliminary experiment using a laboratory X-ray source demonstrated that image contrast is successfully generated by the diffuse scattering from a micrometer-sized structure fabricated on a silicon wafer. This technique works with a large beam with a wide angular spread from a low-brilliance X-ray source, and has potential to become a powerful tool for mapping structures in real space from which ultrasmall-angle X-ray scattering arises.

With the aim of clinical applications of X-ray phase imaging based on Talbot–Lau-type grating interferometry to joint diseases and breast cancer, machines employing a conventional X-ray generator have been developed and installed in hospitals. The machine operation especially for diagnosing rheumatoid arthritis is described, which relies on the fact that cartilage in finger joints can be depicted with a dose of several milligray. The palm of a volunteer observed with 19 s exposure (total scan time: 32 s) is reported with a depicted cartilage feature in joints. This machine is now dedicated for clinical research with patients.

In X-ray grating interferometry, the fabrication of thick transmission gratings with pitches of several micrometers has been a key subject. We report on a metallic glass imprinting technique for fabricating an interferometer grating. We successfully fabricated an 8-µm-pitch, 10-µm-thick grating (26 mm2) made of Pd42.5Ni7.5Cu30P20 metallic glass by using the technique, and as a demonstration we also performed X-ray phase imaging with the grating. The technique can be applied to fabricate not only X-ray but also neutron gratings potentially at high production rates and low costs and is expected to be widely used in the near future.

The ability of phase-contrast x-ray imaging to depict blood vessels without contrast agents was tested by observing livers of a mouse and a rat with synchrotron x rays. Livers were excised by tying arteries and veins to prevent blood from flowing out of the liver. An x-ray interferometer was used to obtain x-ray phase contrast. With the technique of phase-shifting x-ray interferometry, the image mapping x-ray phase shift caused by a liver was measured. The x-ray phase shift caused by blood was substantially different from that caused by other soft tissues; consequently, trees of blood vessels were revealed on the image. Vessels with diameter smaller than 0.1 mm were recognized. This result allows new possibilities for investigation of the vascular system.

Phase-contrast x-ray computed tomography (CT) indicates the distribution of the refractive index and has potential to reveal the structures inside soft tissues without a contrast agent. With a synchrotron x-ray source, phase-contrast x-ray CT with a triple Laue-case x-ray interferometer clearly differentiated various human pathologic tissues in the cases of hepatocellular carcinoma with cirrhosis and metastatic colon carcinoma to the liver, and the images closely corresponded to those obtained with low-magnification optical microscopy.

We tested an X-ray interferometer fabricated to improve the spatial resolution of phase-contrast X-ray computed tomography (CT). The main factor limiting the spatial resolution is the diffraction phenomenon in the crystal wafer of the interferometer. Improvement of the spatial resolution was attempted by thinning the wafer. A preliminary test was performed by checking interference patterns. Thinning the wafer from 1 to 0.24 mm showed clear improvement in the image quality.

A 54-year-old woman was treated for bronchial asthma for 14 yr. In March of 1989, chest roentgenography and computed tomography (CT) revealed development of bilateral pulmonary hilar lymph node enlargement. Positive 67Ga uptake was observed in bilateral pulmonary hili. Although levels of serum angiotensin converting enzyme (ACE) and lysozyme were within normal range, biopsy specimen of scalene lymph nodes showed noncaseating epitheloid-cell granuloma, leading to the diagnosis of sarcoidosis. Steroid therapy ameliorated both sarcoidosis and bronchial asthma. Although the association of sarcoidosis and bronchial asthma is uncommon, there may be an etiological relationship between them.

Recent development in phase-contrast X-ray computed tomography using an X-ray interferometer is reported. To observe larger samples than is possible with our previous X-ray interferometer, a large monolithic X-ray interferometer and a separated-type X-ray interferometer were studied. At the present time, 2.5 cm X 1.5 cm interference patterns have been generated with the X-ray interferometers using synchrotron X-rays. The large monolithic X-ray interferometer has produced interference fringes with 80% visibility, and has been used to measure various tissues. To produce images with higher spatial resolution, we fabricated another X-ray interferometer whose wafer was partially thinned by chemical etching. A preliminary test suggested that the spatial resolution has been improved.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Human tissues obtained from cancerous kidneys fixed in formalin were observed with phase-contrast X-ray computed tomography (CT) using 17.7-keV synchrotron X-rays. By measuring the distributions of the X-ray phase shift caused by samples using an X-ray interferometer, sectional images that map the distribution of the refractive index were reconstructed. Because of the high sensitivity of phase- contrast X-ray CT, a cancerous lesion was differentiated from normal tissue and a variety of other structures were revealed without the need for staining.

Interferometric phase-contrast X-ray imaging is experimentally proved to be sensitive to biological soft-tissue features without the need for staining. Radiographic and tomographic applications of this method are attractive from a diagnostic point of view. In this paper, we have presented the principle of phase-contrast X-ray computed tomography and observation results of human soft tissues. We have shown that the structures of soft structures, such as cancer, are clearly revealed. The good image quality motivated us to study the feasibility of the technique for medical applications. An important technical aim is to make an interferometer having large observation area. A two-crystal X-ray interferometer is a candidate as a device for that purpose. We expect that phase-contrast mammography might be possible with such an interferometer.

We have shown so far that 3D structures in biological sot tissues such as cancer can be revealed by phase-contrast x- ray computed tomography using an x-ray interferometer. As a next step, we aim at applications of this technique to in vivo observation, including radiographic applications. For this purpose, the size of view field is desired to be more than a few centimeters. Therefore, a larger x-ray interferometer should be used with x-rays of higher energy. We have evaluated the optimal x-ray energy from an aspect of does as a function of sample size. Moreover, desired spatial resolution to an image sensor is discussed as functions of x-ray energy and sample size, basing on a requirement in the analysis of interference fringes.

Beryllium windows and graphite heat absorbers used in coherent X-ray beamlines must be optically flat. If the optical path through the window varies by more than λ/4, the X-ray wave front will be distorted after passing through the window, and the divergence of the X-ray beam may be increased. This reduces the beam coherence. Beryllium, graphite and Kapton films have been tested using ultra-small-angle X-ray scattering. Wave-front distortion was also directly observed by means of phase-contrast X-ray microradiography. The measured increase of angular divergence is about 4 µrad. The wave-front distortion is larger than 2π (optical path difference of λ). These are serious problems for utilizing coherent X-ray beams.

Apparatus for phase-contrast X-ray computed tomography using a monolithic X-ray interferometer is presented with some observational results for human breast tissues. Structures characteristic of the tissues were revealed in the phase-contrast tomograms. The procedure of image analysis consists of phase retrieval from X-ray interference patterns and tomographic image reconstruction from the retrieved phase shift. Next, feasibility of phase-contrast imaging using a two-crystal X-ray interferometer was studied aiming at in vivo observation in the future. In a preliminary study, the two-crystal X-ray interferometer was capable of generating fringes of 70% visibility using synchrotron X-rays.

It is difficult to inspect packaged devices such as IC packages and power modules because the devices contain various components, such as semiconductors, metals, ceramics, and resin. In this paper, we demonstrated the effectiveness of X-ray grating interferometry (XGI) using a laboratory X-ray tube for the industrial inspection of packaged devices. The obtained conventional absorption image showed heavy-elemental components such as metal wires and electrodes, but the image did not reveal the defects in the light-elemental components. On the other hand, the differential phase-contrast image obtained by XGI revealed microvoids and scars in the encapsulant of the samples. The visibility contrast image also obtained by XGI showed some cracks in the ceramic insulator of power module sample. In addition, the image showed the silicon plate surrounded by the encapsulant having the same X-ray absorption coefficient. While these defects and components are invisible in the conventional industrial X-ray imaging, XGI thus has an attractive potential for the industrial inspection of the packaged devices.

Stroboscopic X-ray Talbot interferometry that is applicable to time-resolved quantitative X-ray phase imaging of periodic processes in soft materials is demonstrated. The constraint in photon flux was overcome by employing the stroboscopic technique of repeatedly capturing an image of the object at a specific phase of motion and by using polychromatic X-ray sources. By utilizing white synchrotron radiation in conjunction with a high-speed CMOS camera, stroboscopic X-ray Talbot interferometry with a 3 µs temporal resolution was achieved. By incorporating a chopper into a laboratory X-ray Talbot–Lau interferometer, a 5 ms temporal resolution was achieved.

The three-dimensional network of lacunae and canaliculi that regulates metabolism in bone contains osteocytes and their dendritic processes. We constructed a synchrotron radiation X-ray microscope for sequential tomography of mouse tibia first by using a Talbot interferometer to detect the degree of bone mineralization and then by using absorption contrast under a slightly defocused setting to enhance outline contrast thereby visualizing structures of the osteocyte lacuno-canalicular network. The resultant pair of tomograms was precisely aligned with each other, allowing evaluation of mineral density in the vicinity of each osteocyte lacuna and canaliculus over the entire thickness of the cortical bone. Thus, multiscan microscopic X-ray tomography is a powerful tool for analyzing bone mineralization in relation to the lacuno-canalicular network at the submicron resolution level.

High-resolution X-ray computed tomography reveals the three-dimensional structure of microscopic biological tissue and has great clinical potential if the X-ray dose can be reduced (pages 933−935).

We have been developing phase-contrast x-ray computed tomography (CT) to make possible the observation of biological soft tissues without contrast enhancement. Phase-contrast x-ray CT requires for its input data the x-ray phase-shift distributions or phase-mapping images caused by an object. These were measured with newly developed fringe-scanning x-ray interferometry. Phase-mapping images at different projection directions were obtained by rotating the object in an x-ray interferometer, and were processed with a standard CT algorithm. A phase-contrast x-ray CT image of a nonstained cancerous tissue was obtained using 17.7 keV synchrotron x rays with 12 micrometer voxel size, although the size of the observation area was at most 5 mm. The cancerous lesions were readily distinguishable from normal tissues. Moreover, fine structures corresponding to cancerous degeneration and fibrous tissues were clearly depicted. It is estimated that the present system is sensitive down to a density deviation of 4 mg/cm3.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Rationale and Objectives. As a preliminary study for application of phase-contrast X-ray imaging to medicine, we measured the X-ray refractive index of human blood and its influence on image contrast. Methods. Using an X-ray interferometer, the X-ray phase shifts caused by human blood and its ingredients were measured from the interval of interference fringes. Results. The X-ray phase shift caused by blood was 3% larger than that caused by serum. Conclusion. The large phase shift caused by blood is due to red blood cells, which contain hemoglobin molecules with iron atoms. It is possible that blood produces a structure in a phase-contrast X-ray image.

Phase‐contrast radiography using an x‐ray interferometer is presented for observing organic matter. High sensitivity of phase‐contrast radiography is demonstrated with a rat cerebellar specimen without staining it with a contrast medium. The layer structure of the cerebellum can be observed in the obtained image while there is no clear structure in the corresponding absorption‐contrast image. Quantitative image analysis is made possible by converting an x‐ray interference pattern to an x‐ray phase shift distribution. The lipid distribution in the cerebellum is discussed by evaluating x‐ray phase shifts before and after lipid removal.

Wavefront measurement for a hard-X-ray nanobeam using single-grating interferometry based on the Talbot effect and the Fourier transform method was demonstrated in the 1-km-long beamline of SPring-8. 10 keV X-rays were one-dimensionally focused down to 32 nm using a total-reflection elliptical mirror. An intentionally distorted wavefront was generated using a deformable mirror placed just upstream of the focusing mirror. The wavefront measured by interferometry was cross-checked with the phase retrieval method using intensity profiles around the beam waist. Comparison of the obtained wavefront errors revealed that they are in good agreement with each other and with the wavefront error estimated from the shape of the deformable mirror at a ~0.5 rad level.

The neutron interference imaging experiment with two absorption gratings has been done. We develop new way to fabricate absorption gratings for neutron with the pitch of 150 μ m, 180 μ m, and 200 μ m. Compact imaging detector system is developed, whose weight is 2kg. Small break in an acrylic plate, the welded place of Nb plate were observed, it reveals that the neutron interference imaging method can become new method of a nondestructive inspection for reinforced plastics and composite material such as CFRP and so on.

We have developed a hard-X-ray phase-imaging microscopy method using a low-brilliance X-ray source. The microscope consists of a sample, a Fresnel zone plate, a transmission grating, and a source grating creating an array of mutually incoherent X-ray sources. The microscope generates an image exhibiting twin features of the sample with opposite signs separated by a distance, which is processed to generate a phase image. The method is quantitative even for non-weak-phase objects that are difficult to be quantitatively examined by the widely used Zernike phase-contrast microscopy, and it has potentially broad applications in the material and biological science fields.

X-ray phase imaging based on the Lau effect is demonstrated with an incoherent laboratory X-ray source. Its optical configuration resembles the inverse geometry of the X-ray Talbot–Lau interferometer, which employs a large-area amplitude grating. However, the proposed approach avoids the use and hence fabrication difficulty of such a grating, which is advantageous when constructing an X-ray phase imaging apparatus. With a Mo-target source, differential phase images of polymer spheres were successfully obtained and a design concept for downsizing the system is also described.

Intestinal pseudoobstruction and pneumatosis cystoides intestinalis are uncommon complications of progressive systemic sclerosis. We report a 26-year-old woman with this disorder who responded poorly to conventional treatment. Subcutaneous administration of octreotide, a long-acting somatostatin analogue, at a dose of 50 micrograms/day for 3 weeks, relieved symptoms such as nausea and bloating. There was also a marked decrease of intestinal gas accumulation, as documented on X-ray films.

To determine whether left ventricular (LV) filling abnormalities in diabetes are associated with diabetic microangiopathy, and to evaluate the effect of a short-term glycemic control on the filling abnormalities, diastolic filling dynamics were assessed by pulsed Doppler echocardiography in 246 patients with non-insulin-dependent diabetics. Isovolumic relaxation time and the ratio of peak flow velocity of atrial filling wave to peak flow velocity of early filling wave (A/E) were significantly greater in diabetic patients than in age- and sex-matched control subjects. Diabetic patients with retinopathy had significantly greater isovolumic relaxation time and A/E values than those without retinopathy. A/E was significantly decreased 1 month after insulin treatment in those without, but not with retinopathy. It is concluded that LV diastolic filling is impaired in mildly hyperglycemic patients with non-insulin-dependent diabetes mellitus without severe complications, the abnormality being more intense in patients with retinopathy. A short-term glycemic control results in a marked decrease in abnormalities in patients without, but not with retinopathy.

Patients with diabetes were compared with nondiabetic control subjects, with respect to the prevalence of silent myocardial ischemia, by means of treadmill exercise testing and coronary angiography. Results of treadmill exercise testing showed ischemic ST depression in 41 of the 132 diabetic patients (mean age 61 +/- 4 years) and in 42 of the 140 nondiabetic control subjects (mean age 60 +/- 8 years) (31% vs 30%, p = NS). Coronary angiography was performed in 36 of 41 diabetic patients and 34 of 42 nondiabetic control subjects with positive results of treadmill exercise tests, who gave their consent. Among "treadmill-positive" subjects, diabetic patients had a prevalence of silent myocardial ischemia that was 2.2 times higher than that in nondiabetic control subjects (p less than 0.05). Diabetic patients who received insulin had a 2.6 times higher prevalence of silent myocardial ischemia than those who did not (p less than 0.05). Similarly diabetic patients with retinopathy has a 2.5 times higher prevalence of silent myocardial ischemia than those without it (p less than 0.05).

Neural circuits in the central nervous system build our various higher brain functions. However, little is known about mechanisms underlying neuronal information processing in the brain. Anatomical graph structures of real neural networks will provide us with fundamental views to elucidate them. We aim at developing a three-dimensional atlas of neural circuits using high resolution hard X-ray microscopy by synchrotron radiation. We stained neurons of a complete brain from a mouse by the Golgi-Cox method. The heavy metals used in our procedure enhanced X-ray absorption and phase contrast. 3D images of fibriform axons and dendrites of various neurons were reconstructed by back projection. X-ray microscopy with a Talbot interferometer demonstrated finer histological structures of pyramidal neurons in the hippocampus and the cerebral cortex. This observation probably serves as a foundation for achieving a mammalian Connectome Project (identifying complete wiring diagrams of the brain) with X-ray nano-tomography in the near future.

An X-ray Talbot interferometer was combined with an X-ray imaging microscope to generate differential phase contrast. X-ray phase tomography was attained based on the measurement of the differential phase shift using the fringe scanning method. Polymer blend samples were observed and phase separation structures were depicted. The spatial resolution was 1.3 μm in this test experiment, which will be easily improved by increasing the magnification.

Differential phase-contrast X-ray imaging has been performed in a Talbot–Lau configuration, where a multiline X-ray source was used instead of a combination of a hard-X-ray multiple slit and a normal focus X-ray generator. When the multiple slit is used, a high aspect ratio structure is needed and slit width should be below 10 µm for its function. The fabrication and use of such a multislit can be omitted using the presented configuration. The multiline X-ray source was developed by making grooves on a tungsten rotating anode, which was irradiated by an electron beam to generate X-rays. An array of 10 µm line sources with a pitch of 30 µm was formed and combined with a 4.5 µm pitch phase grating and a 5.3 µm pitch amplitude grating to generate differential phase contrast. With a total exposure time of 40 s, a differential phase image depicting cartilages was obtained.

The pharmacokinetics of caffeine (CAF) and its metabolites, dimethylxanthines, were examined in horses administered 2.5 mg/kg of CAF intravenously (i.v.), intramusculary (i.m.), or orally (p.o.). The plasma samples were extracted by Extrelut[○!R] and the concentrations of CAF and metabolites were determined by high performance liquid chromatography (HPLC) with a short column. The pharmacokinetics of CAF after bolus i.v. injection were described by the assumption of a two-compartment model, and those of CAF after i.m. or p.o. administration were done by the assumption of a one-compartment model. The biologic half lives of CAF were 15.5, 18.6, and 16.4 h after administering i.v., i.m. and p.o., respectively. The extent of the bioavailability of the p.o. administration was determined as 1.04 times the dose. The differences in pharmacokinetic parameters were not statistically significant among administration routes. A straight correlation existed between the logarithms of body weights of different species of animals and those of their biologic half lives of CAF. Therefore, the biologic half life of CAF in an animal might be predictable as a function of its body weight.

We report here a case of Meneetrier's disease (MD) that required a prolonged period for remission after eradication therapy of Helicobacter pylori (HP). The appropriate time needed to judge the efficacy of the eradication therapy for HP infection in an MD case is discussed.

A new type of differential phase X-ray imaging microscopy attained by combination of an X-ray imaging microscope and an X-ray Talbot interferometer is described. An X-ray Talbot interferometer was set up so that a moire-fringe pattern appeared on the image plane of an X-ray imaging microscope. The wavefront inclination (differential phase shift) caused by a weakly absorbing polymer sample was measured from the fringes using the fringe-scanning method and with a spatial resolution of 1 µm. Phase tomography was also performed and the internal structures of a piece of polymer blend were depicted.

We assesses the efficiency of x-ray Talbot interferometry (XTI), a technique based on the Talbot effect for measuring a wavefront gradient, in terms of how quickly it can capture a high-quality phase image with a large signal-to-noise ratio for a given incident photon number. Photon statistics cause errors in the phase of the moiré fringes and impose a detection limit on the wavefront gradient. The relation between the incident photon number and the detection limit is determined, and a figure of merit of XTI for a monochromatic cone beam is then defined. The dependence of the figure of merit on optical system parameters, such as grating pitch and position, is then discussed. The effects of varying the pattern height and linewidth of the second grating are shown for rectangular and trapezoidal teeth. Finally, we show how to design a practical cone-beam Talbot interferometer for certain boundary conditions.