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We investigated the effects of poisoning and restoration of PdCuSi-metallic glass (MG), which is a sensing material that offers low power consumption and fast response times when used in capacitive MEMS hydrogen sensors. Four poisoning gases were used: hexamethyldisilazane (HMDS), H2S, SO2, and NO2. Exposure to H2S resulted in metal sulfide forming at the surface of the PdCuSi-MG, although the sulfur did not diffuse into the PdCuSi-MG. Exposure to NO2 only resulted in the nitrogen being adsorbed without bonding to metals. The poisoning elements were desorbed by heating. Exposure to H2S and SO2 degraded the hydrogen sensitivity in terms of resistance of the PdCuSi-MG, although exposure to HMDS and NO2 only slowed down the response time. These degradations were recovered by heating. We next examined forming a refresher layer under PdCuSi-MG in a hydrogen sensor. The hydrogen sensitivity of the H2S-exposed hydrogen sensor was restored by performing a refresh operation for a few minutes.

Currently, researchers are actively conducting studies and experiments on soft robots due to their increasing abilities to cooperate with humans. Particular attention is being paid to pneumatic artificial muscles because of their flexibility and relatively light weight as actuators. Among the multiple types of pneumatic artificial muscles, the straight-fiber-type has a structure, which is typically configured in a cylindrical rubber tube reinforced by fibers in the axial direction. The application of an internal pressure expands the tube in the radial direction, while it contracts in the axial direction. In this study, the deformation of such tubes was theoretically analyzed. First, the differential equation for the cylinder profile was derived, and the solution then obtained in the closed form, when the rubber is relatively soft enough compared to the fiber. Finally, for a large enough inner pressure, the profile of the reinforced rubber cylinder was derived from the incomplete elliptic integral. Moreover, the spring constant, the contraction ratio, and the maximum stress were obtained regarding the cylinder length. The spring constant linearly increased with the initial length of the cylinder. The contraction ratio also increased with the initial cylinder length up to 54.3%. The maximum stress was found to be related to the elastic modulus of the rubber but not to the inner pressure; when the cylinder length was three to five times larger than the initial diameter of the cylinder, the rubber exhibited small a maximum stress and large contraction ratio.

In this paper, we demonstrate detection of a smoldering fire by using a low-power hydrogen sensor. To detect the low levels of hydrogen gas generated by smoldering fires, a capacitive MEMS hydrogen sensor with a microheater was proposed. The microheater improved hydrogen sensitivity on the order of ppm by accelerating the oxide desorption at the sensing film surface. Low thermal capacity and high thermal resistance structure enabled localized heating of the sensitive film at a highspeed of 1 ms, thereby achieving sub-mW low power consumption by intermittent sensing operation. The fabricated hydrogen sensor was installed in a small wireless module and placed on the ceiling 3 meters from the cotton fire source. Our hydrogen sensor successfully detected 66 ppm hydrogen generated by the smoldering fire, and also detected the elimination of hydrogen by exhaust.

In recent years, soft robots, such as those with high human affinity and those that excellently imitate the movements of natural creatures, have gained considerable attention. In soft robots, structurally flexible soft actuators need to be used, not conventional motors or hydraulic/pneumatic cylinders. Various types of soft actuators have been developed depending on the driving principle. A pneumatic rubber artificial muscle is a kind of soft actuator that acquires power through injection of a working fluid, such as air, into an elastic structure, such as rubber. In this study, the authors developed an actuator, namely, the straight-fiber-type artificial muscle, which exhibits excellent contraction characteristics. This artificial muscle consists of a rubber tube that contains reinforcing fibers arranged in the axial direction. When air pressure is applied to the rubber tube, the artificial muscle expands only in the radial direction and contracts in the axial direction due to the restraining effect of the reinforcing fiber. While this artificial muscle exhibits excellent contraction properties, it has some drawbacks. One is the difficulty in enclosing the reinforced fibers that have accumulated in the rubber tube, making this artificial muscle difficult to manufacture. In this study, we investigated short-fiber-reinforced artificial muscles that can be easily manufactured. First, a short-fiber-reinforced rubber was prepared, and anisotropy was evaluated via a tensile test. Then, the short-fiber-reinforced artificial muscles were prepared, and their contractions rates were evaluated. The results confirmed that a short-fiber-reinforced rubber can be useful for the manufacture of artificial muscles.

It is not always easy to establish specific antibodies against receptors. Most receptors are hydrophobic and have complicated three-dimensional structures, making them difficult to use as immunogens. Thus, we developed receptor detection methods with a fluorescein-labeled ligand as an antibody alternative, which we referred to as a western ligand blot (WLB) and ligand derivative stain (LDS). Kisspeptin receptor (Kiss1R) was detected by its ligand. Kiss1R expression was confirmed in eight human cell lines by the WLB and in four pathological tissues by the LDS. Next, Kiss1R was stained by LDS in organs, revealing Kiss1R expression by [

This paper reports the first demonstration of Ultra-Low-Power (ULP) operation below 1 µW and noise reduction realized by a monolithic 3-axis accelerometer using a SiGe-MEMS-on-CMOS technique. In this work, the ULP operation is attributed to incorporating high-sensitivity SiGe-MEMS and low-power CMOS circuit with a monolithic configuration. The power consumption is confirmed to be 273 nW in an active mode and 160 nW in a standby mode. Furthermore, this work first evaluates the quantitative benefit of the monolithic configuration in view of noise reduction, and the result is a 30% lower noise density compared to a two-chip configuration using wire bonding, stemming from a 53% reduction of the parasitic capacitance. This work's approach enabling ULP operation and the noise reduction will contribute to the long battery life of sensors desired for IoT applications.

We investigated the effects of N 2 plasma treatment on Mn-Mn bonding strength and the electrical properties of a Mn layer between SiO 2 layers. Si atoms introduced into the Mn layer by N 2 plasma play an important role in improving bonding strength. Moreover, we confirmed that the Mn layer treated with N 2 plasma has the desired leakage property.

It is not always easy to establish specific antibodies against receptors. Most receptors are hydrophobic and have complicated three-dimensional structures, making them difficult to use as immunogens. Thus, we developed receptor detection methods with a fluorescein-labeled ligand as an antibody alternative, which we referred to as a western ligand blot (WLB) and ligand derivative stain (LDS). Kisspeptin receptor (Kiss1R) was detected by its ligand. Kiss1R expression was confirmed in eight human cell lines by the WLB and in four pathological tissues by the LDS. Next, Kiss1R was stained by LDS in organs, revealing Kiss1R expression by [67 Ga]Ga-DOTA-kisspeptin 10 accumulation. As a result, Kiss1R-expressing cells in each organ could be stained with fluorescein-labeled kisspeptin 14 instead of an antibody and observed by light microscopy. The combination of the WLB and LDS allows identification of receptors in tissues, which can be readily applied to target receptor detection by a synthetic ligand derivative.

In this paper, for the first time we demonstrate the material benefits of SiGe for MEMS applications based on the results of fabricated devices. To achieve SiGe inertial MEMS, we develop the deposition process for thick, low-temperature poly-SiGe film with which film stress is controlled precisely, and fabricate SiGe accelerometers having 20µm thickness. We clarify that the SiGe accelerometer shows higher sensor sensitivity and lower power consumption compared to Si one and is thus suitable for future ultra-low-power sensors.

A pneumatic artificial muscle is an air pressure-activated rubber actuator. It is lightweight and high in power density compared to motorized actuators and fluid-powered cylinders. In addition, it shows high compatibility with the human body because it has good flexibility. The authors have developed a straight-fiber-type pneumatic artificial muscle (SF-ARM) with high output and contraction amounts compared to those of the widely used McKibben-type artificial muscle. Although the fatigue life of the McKibben type has been examined, similar studies have not yet been performed for SF-ARM. In this study, the extension of the lifetime of SF-ARM, development of high-deformation rubber material, and examination of the SF-ARM aspect ratio were performed. First, from deformation analysis by the finite element method, the target elongation value of the rubber material was determined and a suitable material was developed. Next, the fatigue life and contraction characteristics were measured by reducing the strain of the rubber material by changing the aspect ratio. The results showed a relationship between the lifetime and the shape of the artificial muscle. We demonstrate that the relationship between the lifetime and contraction force and ratio, according to the application, can be selected by manipulating the shape and the size of the SF-ARM.

To compare Si and poly-SiGe as MEMS structural materials having 20 pm-thick, we fabricated a capacitive accelerometer on an 8-inch Si substrate using CMOS standard process and measured capacitance sensitivities of an identical sensor design. As a result, we found that the sensitivity of the SiGe sensor is 2.1 times larger than that of the Si sensor. We also confirmed that the SiGe sensor can attain lower noise level as well as lower power consumption, thanks to the higher mass density of SiGe and availability of CMOS-embedded SiGe MEMS structure. The results indicate that the poly-SiGe film is promising candidates for future CMOS-embedded sensor technology applications.

Flattened cross-linked hollow poly(divinylbenzene) (PDVB) particles with encapsulated n-hexadecane (HD) were successfully prepared through suspension polymerization using the self-assembling of phase-separated polymer (SaPSeP) method, in which the solid dispersion medium was gelled by gellan gum and compressed. The solid phase induced by gellan gum can be easily changed to a liquid state by heating, allowing the obtained particles to be easily recovered after polymerization. When the polymerization was conducted in the solid dispersion medium without compression, spherical hollow PDVB/HD composite particles were obtained. In contrast, when the polymerization was conducted with the compression of the solid dispersion medium, flattened hollow PDVB/HD composite particles were obtained. The shape of the flattened hollow polymer particles was controlled by changing the compression ratio of the solid phase, and the size could also be controlled by changing the DVB/HD droplet size using the Shirasu porous glass membrane-emulsification technique. Furthermore, flattened hollow particles larger than 20 μm in size were obtained, but it was difficult to obtain spherical hollow particles of such large size using the SaPSeP method.

An ethanol-utilizing Fe(III)-reducing bacterial strain, OSK2A(T), was isolated from a lotus field in Aichi, Japan. Phylogenetic analysis of the 16S rRNA gene sequences of OSK2A(T) and related strains placed it within Geobacter sulfurreducens PCA(T). Strain OSK2A(T) was shown to be a Gram-negative, motile, rod-shaped bacterium, strictly anaerobic, 0.76-1.65 µm long and 0.28-0.45 μm wide. Its growth occurred at 20-40℃, pH 6.0-8.1, and it tolerated up to 1% NaCl. The G+C content of the genomic DNA was 61.2 mol% and DNA-DNA hybridization value with Geobacter sulfurreducens PCA(T) was 60.7%. The major respiratory quinone was MK-8. The major fatty acids were 16：1 ω7c, 16：0, 14：0, 15：0 iso, 16：1 ω5c, and 18：1 ω7c. Strain OSK2A(T) could utilize H2, ethanol, acetate, lactate, pyruvate, and formate as substrates with Fe(III)-citrate as electron acceptor. Amorphous Fe(III) hydroxide, Fe(III)-NTA, fumarate, malate, and elemental sulfur were utilized as electron acceptors with either acetate or ethanol as substrates. Results obtained from physiological, DNA-DNA hybridization, and chemotaxonomic tests support genotypic and phenotypic differentiation of strain OSK2A(T) from its closest relative. The isolate is assigned as a novel subspecies with the name Geobacter sulfurreducens subsp. ethanolicus, subsp. nov. (type strain OSK2A(T)=DSMZ 26126(T)=JCM 18752(T)).

To disclose the neuropathological progression course of Machado-Joseph disease (MJD), magnetic resonance imaging (MRI) findings of six genetically confirmed MJD cases (four males and two females, including an autopsied female, all unrelated to one another) were further investigated on neurodegeneration. Brain MRI studies were repeated in all cases at different stages of the disease. Ages at the first MRI study ranged from 47 to 65 years (55.2 ± 7.1), with observation periods from 4.5 to 10.6 years (6.95 ± 2.48). We paid particular attention to two types of previously reported MRI findings detectable using T2-weighted images. One is located just outside the internal capsules, and another in the pons. A linear high-intensity change along the internal capsules was detected in all cases, and showed progression during the observation period. A comparison between MRI and autopsy findings suggested that the lesion might reflect degeneration with neuronal loss, astrocytosis, and gliosis in the internal segment of the globus pallidus. A cross-shaped high-intensity change in the pons was well advanced but still incomplete in all cases. In this region, pontine transverse fibers were atrophic, while longitudinal fibers remained intact. Pontine nuclei showed apparent nerve cell loss, and the remaining cells had many 1C2-positive intranuclear inclusions. Since these findings were detected both by lifetime images and by postmortem examination, MRI intensity changes could track the progression of neurodegeneration. Based on a comparison between MRI findings and neuropathology, the degeneration of an internal segment of the globus pallidus (one of the pathological features of MJD) had progressed following the initial symptoms.

Background Interleukin-19 (IL-19), a member of the IL-10 family, is characterized as the cytokine suppressing the release and function of several proinflammatory cytokines. For regulation of local reaction in allergic rhinitis (AR), IL-19 might play an especially important role. Methods We examined effects of IL-19 on IL-4-induced eotaxin production by human nasal fibroblasts. Early receptor-mediated events (expression of the suppressors of cytokine signaling (SOCS) and phosphorylation of signal transducer and activator of transcription 6 [STAT6]) by IL-19 was examined. Knockdown methods by RNAi were administered to investigate the involvement of those signal transductions. Results Pretreatment with IL-19 downregulates IL-4-induced eotaxin production, but not interferon-γ (IFN-γ)-induced RANTES. Pretreatment with IL-19 suppressed the IL-4-induced STAT6 phosphorylation. The IL-19 induced SOCS-1, but not SOCS-3 or SOCS-5. The SOCS-1 knockdown by RNAi diminished pretreatment with IL-19-induced down-regulation of eotaxin production. Conclusions These results suggest that IL-19 down-regulates IL-4-induced eotaxin production via SOCS-1 in human nasal fibroblasts. In non-hematopoietic cells in AR, IL-19 might be an immunosuppressive factor.

We conclude that the capsaicin inhalation test is useful to directly assess cough reflex and sensation around the larynx, while it indirectly reflects central nervous system function.To understand the state of the cough reflex before patients with dysphagia start eating.We studied the cough reflex by the capsaicin inhalation test in 21 patients with dysphagia and 12 healthy persons without dysphagia.The control group showed a cough reflex at a capsaicin concentration of 2.61 μM (0.98-7.80), while patients with mild dysphagia did so at 7.28 μM (1.95-15.6), those with moderate dysphagia at 22.07 μM (15.6-62.5), and those with severe dysphagia at 71.75 μM (31.2-250). Control vs mild p0.01, control vs moderate p0.01, control vs severe p0.01, mild vs moderate p0.01, mild vs severe p0.01, moderate vs severe p0.05. There was a significant correlation between the grade of dysphagia and the threshold capsaicin concentration that provoked a cough reflex (ρ = -0.796, p0.001).

Fungal sinusitis is fairly common and often incidentally diagnosed in X-ray or computed tomography imaging (CT). Most cases are largely asymptomatic and noninvasive. In invasive cases, subjects are frequently immunocompromised hosts suffering from diabetes mellitus, using steroids or immunosuppressive drugs, or aged. The invasive fungus destroys tissues, muscles, and bones, occasionally even causing cranial and orbital complications. Such fatal fungal sinusitis requires intensive, appropriative treatment if subjects are to survive. Antifungal drugs have recently been reported to be effective against invasive fungal sinusitis. We present two cases of invasive aspergillus sinusitis showing orbital apex syndrome, both of which were improved using antifungal drugs.

Background: Allergic rhinitis (AR) is recognized as a major health problem worldwide, and its prevalence depends on the age range of the subjects. The aims of this study were to determine the current prevalence of AR, effects of age on the prevalence of IgE sensitization to inhalant allergens, and serum total IgE levels in Japanese subjects. Methods: We conducted a survey of 1,540 subjects between 20 and 49 years of age in 2006 and 2007 and examined the prevalence of AR and sensitization to 7 common aeroallergens. We measured serum total IgE and specific IgE to 7 aeroallergens. AR was determined based on symptoms, predominantly in the nose and eyes, caused by aeroallergens as mentioned in a questionnaire and sensitization to any of the 7 aeroallergens as assessed by measurement of serum specific IgE. Results: The prevalence of AR was 44.2% (681 of the 1,540 subjects) and there was no difference among age decades. Of the 1,540 subjects, 1,073 (69.7%) were sensitized to at least 1 of the 7 aeroallergens. The most common allergen in AR was Japanese cedar pollen (89.6%, 610 of the 681 with AR) in all the age decades examined. The sensitization rate to mites was significantly higher in the younger subjects. Conclusion: Our data suggest that the prevalence of AR between 20 and 49 years of age has increased by nearly 10% during the last 10 years. Cedar pollen and mites were predominant allergen sources among the 7 aeroallergens in the Japanese population.

Gene therapy has become a focus not only in the study of cancer but also lifestyle-related diseases. In case of chronic rhinosinusitis with nasal polyps and aspirin-induced asthma, nasal polyps poorly respond to a local administration of steroid. The Bax and Bcl-2 proteins play important roles in the regulation of apoptosis. The treatment of steroid (prednisone) induced apoptosis in the fibroblast. The Bax accelerates apoptosis. Apoptosis is very important in the anti-inflammatory mechanism. In this study, we investigated whether the overexpression of Bax in human fibroblasts influences apoptosis by treatment with a steroid (prednisolone) in vitro. Human nasal fibroblasts were isolated from small pieces of nasal polyp and were transfected with a bax gene-bearing mammalian expression vector. Human nasal fibroblasts were transiently transfected with the expression vector hBaxpcDNA3 (Bax-NF) or native pcDNA3 (Neo-NF). Both transfectants (Bax-NF, Neo-NF) and wild-type-nasal fibroblast (wt-NF) were cultured in conditioning medium and treated with each concentration of prednisolone for 72 h. Prednisolone at a concentration of 10 ng/ml decreased the viability of Bax-NF compared to that of Bax-NF in the absence of prednisolone. The cytotoxicity of prednisolone to Bax-NF was significantly higher than that to Neo-NF or wt-NF (p < 0.01) and the susceptibility of Bax-NF to prednisolone was about 1,000 times that of Neo-NF or wt-NF. We found that the transfer of the exogenous bax gene enhanced the induction of apoptosis by steroid-treatment in human nasal fibroblasts. Therefore, we suggest that exogenous Bax protein expression by gene transfer might be useful for the treatment of nasal polyps. We will further the preclinical study in improving steroids dose and in adopting to transfer bax gene to the nasal polyps by intranasal injection, thus providing a more effective and safer way for the nasal polyps that poorly respond to a local administration of steroids.

General data acquisition for single photon emission computed tomography (SPECT) is performed in 90 or 60 directions, with a coarse pitch of approximately 4-6 degrees for a rotation of 360 degrees or 180 degrees , using a gamma camera. No data between adjacent projections will be sampled under these circumstances. The aim of the study was to develop a method to improve SPECT image quality by generating lacking projection data through interpolation of data obtained with a coarse pitch such as 6 degrees .The projection data set at each individual degree in 360 directions was generated by a weighted average interpolation method from the projection data acquired with a coarse sampling angle (interpolated projection data estimation processing method, IPDE method). The IPDE method was applied to the numerical digital phantom data, actual phantom data and clinical brain data with Tc-99m ECD. All SPECT images were reconstructed by the filtered back-projection method and compared with the original SPECT images.The results confirmed that streak artifacts decreased by apparently increasing a sampling number in SPECT after interpolation and also improved S/N ratio of the root mean square uncertainty value. Furthermore, the normalized mean square error values, compared with standard images, had similar ones after interpolation. Moreover, the contrast and concentration ratios increased their effects after interpolation.These results indicate that effective improvement of image quality can be expected with interpolation. Thus, image quality and the ability to depict images can be improved while maintaining the present acquisition time and image quality. In addition, this can be achieved more effectively than at present even if the acquisition time is reduced.

Background Mature cystic teratomas of the major salivary glands are rare. This report describes a case of a mature cystic teratoma of the left parotid gland, including the cytologic and bistopatbologic findings. Case A 17-year-old young woman presented with a slow-growing left parotid mass that had been present for 4 years. Preoperative fine needle aspiration cytology showed the presence of acinar and ductal cells, foamy cells and multinucleated giant cells. Imprint cytology of the surgical material showed the presence ofsome squamous cells and sebaceous gland-like cells with bair shafts. Cellular atypia was inconspicuous. Grossly, the 3-cm lesion was unicystic and embedded within the parotid gland parenchyma. Microscopically, the inner surface of the cyst was lined with keratinized squamous epithelium. The cyst wall contained skin adnexa such as sebaceous, eccrine and apocrine glands, as well as hair follicles. Some mature cartilage tissue was also detected. Foreign body granulomatous change was seen focally. No immature tissue or malignant transformation was found. Conclusion There is no previous report describing the cytologic findings of a mature cystic teratoma of the parotid gland. Mature cystic teratomas should therefore be considered in the differential diagnosis of a cystic lesion of the parotid gland.

By using a stacked mask process (S-MAP) with spun-on-carbon (SOC) film, 38 nm line patterns were successfully etched by controlling the ion energy using high-bias-frequency dual-frequency-superimposed (DFS) rf capacitively coupled plasma in combination with the low hydrogen content SOC film. It was found that ions with higher energy enhance the fluorination of SOC and induce pattern wiggling under fluorine exposure. By using a higher bias frequency to control the ion energy distribution and reduce the maximum ion energy, the SOC pattern wiggling was effectively suppressed.

(123)I is a radionuclide frequently used in nuclear medicine imaging. The image formed by the 159 keV photopeak includes a considerable scatter component due to high energy gamma-ray emission. In order to evaluate the fraction of scattered photons, a Monte Carlo simulation of a scintillation camera used for (123)I imaging was undertaken. The Monte Carlo code consists of two modules, the HEXAGON code modelled the collimator with a complex hexagonal geometry and the NAI code modelled the NaI detector system including the back compartment. The simulation was carried out for various types of collimators under two separate conditions of the source locations in air and in water. Energy spectra of (123)I for every pixel (matrix size = 256 x 256) were obtained by separating the unscattered from the scattered and the penetrated photons. The calculated energy spectra (cps MBq(-1) keV(-1)) agreed with the measured spectra with approximately 20% deviations for three different collimators. The difference of the sensitivities (cps MBq(-1)) for the window of 143-175 keV was less than 10% between the simulation and the experiment. The partial sensitivities for the scattered and the unscattered components were obtained. The simulated fraction of the unscattered photons to the total photons were 0.46 for LEHR, 0.54 for LEGP and 0.90 for MEGP for the 'in air' set-up, and 0.35, 0.40 and 0.68 for the 'in water' set-up, respectively. The Monte Carlo simulation presented in this work enabled us to investigate the design of a new collimator optimum for (123)I scintigraphy.

Iodine-131 is widely used for radionuclide therapy because of its β-particle and for diagnostic imaging employing its principal gamma ray. Since that principal gamma ray has the relatively high energy of 364 keV, small animal single-photon emission computed tomography (SPECT) imaging systems may be required to possess the ability to image such higher energy photons. The aim of this study was to investigate the possibility of imaging I-131 using its 284 keV photons instead of its 364 keV photons in a small animal SPECT imaging system dedicated to the detection of low-medium-energy photons (below 300 keV). The imaging system used was a commercially available preclinical SPECT instrument with CZT detectors that was equipped with multi-pinhole collimators and was accompanied by a CT imager. An energy window for I-131 imaging was set to a photopeak of 284 keV with a low abundance compared with 364 keV photons. Small line sources and two mice, one of each of two types, that were injected with NaI-131 were scanned. Although higher counts occurred at the peripheral region of the reconstructed images due to the collimator penetration by the 364 keV photons, the shape of the small line sources could be well visualized. The measured spatial resolution was relatively poor (~1.9 mm for full width at half maximum and ~3.9 mm for full width at tenth maximum). However, a good linear correlation between SPECT values and the level of I-131 radioactivity was observed. Furthermore, the uptake of NaI-131 to the thyroid gland for the two mice was clearly identified in the 3D-SPECT image fused with the X-ray CT image. We conclude that the use of an energy window set on the photopeak of 284 keV and the multi-pinhole collimator may permit I-131 imaging for a preclinical CZT-SPECT system that does not have the ability to acquire images using the 364 keV photons.

The tensile shear adhesive-free adhesion properties induced by electrostatic interactions between poly(acrylic acid) (PAA) and poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) chains grafted onto polyethylene (PE) with low-density (LDPE) or high-density (HDPE) plates were studied. PAA- or PDMAEMA-grafted PE plates were immersed in a HCl or NaOH solution or water for 24 h, and their electrostatic properties were changed before they were overlapped with each other and heat-pressed. The breaking of the substrate between the two plates with water-swollen grafted layers was observed in the low range of grafted amounts in comparison with immersion in the acidic and basic solutions. The ability of the two plates with grafted polymer chains swollen in water to strongly bond with each other was a result of electrostatic interactions formed by positively charged PDMAEMA and negatively charged PAA chains. The breaking of the substrate in the case of adhesive-free adhesion between quaternized PDMAEMA-grafted and PAA-grafted PE plates immersed in the basic solution occurred with lower grafted amounts of PAA. This came from the strong attractive force between dissociated anionic PAA chains and quaternized cationic PDMAEMA chains in the basic solution. In addition, the adhesive-free adhesion strength of HDPE plates with the same grafted polymer chains encountered the breaking of the substrate with lower grafted amounts than that of LDPE plates. It was concluded that the grafting of polymer chains onto HDPE plates with high crystallinity was considerably restricted to the outer surface regions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2632–2638, 2006

For more effective Tl-201 imaging, the location and width of the energy window set on the Hg-201 x-rays photopeak was investigated using Monte Carlo simulation and phantom experiments. We calculated energy spectra and investigated the amount of primary and scattered photons within various energy windows set on the x-rays photopeak. The energy resolution (ER) at 71 keV (the peak of the x-rays photopeak) was changed to 10%, 12%, 14% and 16%. The relationships between the energy window and the primary counts rate or the scatter fraction (= scattered counts/primary counts, SF) were obtained. By compromise between the primary counts rate and the SF for ER = 12%, the optimum energy window was determined as a wider off-peak window, 77 keV +/- 14.3% (66-88 keV). This off-peak window increased the primary counts rate by 12.5% and decreased the SF by -17% as compared with the conventional on-peak energy window (71 keV +/- 10%, 64-78 keV). When this off-peak widow acquisition was compared with the conventional on-peak window one on a gamma camera, planar and SPECT images using the off-peak widow clearly showed superior results qualitatively and quantitatively.

Objective: Attenuation artifacts adversely affect the diagnostic accuracy of myocardial perfusion imaging. We assessed the clinical usefulness of X-ray CT based attenuation correction (AC) in patients undergoing myocardial perfusion imaging by comparing their myocardial AC- and non-corrected (NC) SPECT images with the coronary angiography (CAG).Methods: We retrospectively reviewed the myocardial SPECT images of 30 patients (18 men, 12 women; mean age 68 years). Thirteen of 30 patients with coronary artery disease (CAD) and 17 without CAD were confirmed by CAG. They underwent sequential CT and myocardial SPECT imaging with thallium-201 (111 MBq) under an exercise or pharmacological stress protocol using our combined SPECT/ CT system. Two readers reviewed the myocardial SPECT images for the presence of CAD on a 4-point scale where 1 = normal, 2 = probably normal, 3 = probably abnormal, and 4 = abnormal. Two reading sessions were held. First, non-corrected (NC)-SPECT and second, AC-SPECT images using X-ray CT images were interpreted. Interobserver variability was assessed with kappa statistics. Diagnostic performance (accuracy) of coronary arterial stenosis was compared between AC- and NC-images.Results: Interobserver agreement for visual assessment was substantial or almost perfect. For AC-images, the observer consensus for analysis was 0.84 for the LAD-, 0.87 for the LCX-, and 0.71 for the RCA-territory. For NC-images, it was 0.91, 0.71, and 0.78. AC resulted in statistically significant improvements in overall diagnostic accuracy (sensitivity/ specificity/accuracy = 76%/93%/89%, 67%/86%/81%, respectively, for AC- and NC-images).Conclusions: Because of an increase in the specificity, diagnostic accuracy was significantly increased on AC-images. These preliminary data suggest that X-ray CT based AC in myocardial SPECT imaging has the potential to develop into a reliable clinical technique.