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In this article, an approach used for the inspection tasks in the WRS2020 Plant Disaster Prevention Challenge is explained. The tasks were categorized into three categories: reading pressure gauges, inspecting rust on a tank, and inspecting cracks in a tank. For reading pressure gauges, the “you only look once” algorithm was used to focus on a specific pressure gauge and check the pressure gauge range strings on the gauge using optical character recognition algorithm. Finally, a previously learned classifier was used to read the values shown in the gauge. For rust inspection, image processes were used to focus on a target plate that may be rusted for rust detection. In particular, it was necessary to report the rust area and distribution type. Thus, the pixel ratio and grouping of rust were used to count the rust. The approach for crack inspection was similar to that for rust. The target plate was focused on first, and then the length of the crack was measured using image processing. Its width was not measured but was calculated using the crack area and length. For each system developed to approach each task, the results of the preliminary experiment and those of WRS2020 are shown. Finally, the approaches are summarized, and planned future work is discussed.

Pleural empyema often requires surgical intervention; however, surgical invasiveness should be minimized. We utilized the modified Claget procedure as an alternative to thoracoplasty for acute pleural empyema with a dead space. The procedure was performed as follows: first, 500 mg of kanamycin and 500,000 units of polymyxin sulfate dissolved in 10-100 ml saline was instilled intrapleurally via tube thoracostomy. The chest tube was clamped overnight and then removed. The modified Clagett procedure might be effective for acute pleural empyema with a dead space without pulmonary or bronchopleural fistula. We report our successful experience of performing modified Clagett procedure for pleural empyema with a dead space, through a detailed case presentation.

To evaluate the correlation of ADC and IVIM-diffusion kurtosis (DK) model parameters with quantitative histological parameters of whole-slide imaging (WSI).This retrospective study (September 2015-July 2016) included 37 consecutive patients (all females; median age: 64 years, range, 41-82 years), each with a single invasive breast ductal carcinoma lesion with a mass appearance on preoperative MRI. DWI with b-values of 0, 50, 100, 300, 550, 850, and 1000 s/mmThe ADC was significantly correlated with the area ratio of interstitium (r = 0.53, p = 0.00082) and entropy (r = -0.58, p = 0.00019). k was significantly correlated with the area ratio of cancer cell nuclei (r = 0.53, p = 0.00079).Since the ADC reflected the area ratio of interstitium and entropy, and diffusion kurtosis reflected the area ratio of cancer cell nuclei, these parameters may be effective in distinguishing between benign and malignant breast tumours and in grading breast cancer.

Background During endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), the sonographic findings of B-mode imaging, as well as endobronchial elastography, can be obtained noninvasively and used for the prediction of nodal metastasis. Methods Patients with lung cancer or suspected lung cancer who underwent EBUS-TBNA were recorded prospectively and reviewed retrospectively. Both the B-mode sonographic and elastographic findings were independently evaluated for each lymph node. The sonographic features were classified according to previously published criteria. If oval shape, indistinct margins, homogenous echogenicity, and the absence of coagulation necrosis sign were all observed by B-mode imaging, then the lymph node was judged to be benign by sonographic imaging. In addition, if the stiffer area comprised more than 31% of the entire lymph node area, then the lymph node was judged to be malignant by elastography. We compared the results of these imaging-based predictions with the pathological diagnoses. Results The prevalence of nodal metastasis was 78/228 (34.2%). B-mode sonography predicted 95.8% of benign lymph nodes, and elastography predicted 72.1% of malignant lymph nodes. By combining the two modalities, 59 of 71 (83.1%) lymph nodes judged as malignant by both analyses were pathologically proven to be malignant, and 101 of 105 (96.2%) lymph nodes judged as benign by both analyses were pathologically proven to be benign. Conclusion The combination of elastography and sonographic findings showed good sensitivity and a high negative predictive value, which may facilitate selecting the most suspicious lymph nodes for biopsy. Key points Significant findings of the study. The combination of endobronchial elastography and sonography resulted in a higher diagnostic yield than either modality alone for predicting benign and malignant lymph nodes in patients with lung cancer. What this study adds The combination of endobronchial elastography and sonography will help clinicians identify the most suspicious lymph nodes for puncturing during EBUS-TBNA, which may improve the efficiency of EBUS-TBNA.

Conventional volumetric analysis could not detect ipsilateral atrophy of the mammillary body in patients with unilateral hippocampal sclerosis. By using thin-slice-reconstructed volumetric analysis, we investigated whether the mammillary body volume is smaller on the hippocampal sclerosis side than in healthy subjects or the non-hippocampal sclerosis side. This retrospective study included 45 patients with unilateral hippocampal sclerosis and 30 healthy subjects. Three-dimensional T1WI of 1 mm thicknesses were oversampled to a thickness of 0.2 mm (thin-slice-reconstructed images), and the mammillary bodies were segmented manually to determine mammillary body volume on each side. Mammillary body volumes on the hippocampal sclerosis side were compared with those in healthy subjects or the non-hippocampal sclerosis side. In patients with right hippocampal sclerosis, right mammillary body volume was both significantly smaller than that in healthy subjects (30.3 ± 10.3 vs. 43.3 ± 8.07 mm3, P

The degradation and mineralization of 2-propanol (IPA) in an aqueous solution were investigated using a TiO2 photocatalyst immobilized on a nonwoven fabric, both in the presence and absence of O3 microbubbles and H2O2. The influence of parameters like the H2O2/O3 molar ratio and the type of ultraviolet (UV) lamp used on the IPA degradation reaction was investigated. The main active species in IPA degradation and mineralization are thought to be hydroxyl radicals, generated as a consequence of the H2O2–O3 (peroxone) reaction, the photolysis of H2O2 and O3, and the TiO2-based photocatalytic reaction. The fastest IPA degradation rate was obtained under UV irradiation in the presence of H2O2, O3, and TiO2 immobilized on a nonwoven fabric. Because under these conditions sufficient UV light is irradiated on the catalyst surface, we found that the optimum ratio for the peroxone reaction between O3 and H2O2 did not change in our reaction system, even in the presence of the TiO2 immobilized nonwoven fabric. This means that the UV light contributes effectively to the photocatalytic reaction without interfering with the peroxone process, and that the photocatalyst does not only promote the decomposition of IPA but also the mineralization of the degradation products. We explored the influence of the base material used to manufacture the nonwoven fabric on the mineralization rate and found that the use of polyethylene terephthalate (instead of polyolefin fibers) to prepare the nonwoven fabric substantially accelerated the rates of the IPA, acetone, and total organic carbon decomposition reactions.

BACKGROUND There is limited evidence of parametric MR mapping to characterize carotid plaques associated with cerebral ischemic events. PURPOSE To explore the apparent diffusion coefficients (ADCs) and longitudinal relaxation rates (R1 ) of carotid plaques, including areas of hemorrhage, lipid-rich/necrotic core (LR/NC) without hemorrhage, and fibrous tissue (Fbr) STUDY TYPE: Prospective. SUBJECTS Twelve patients who underwent carotid endarterectomy. FIELD STRENGTH/SEQUENCE R1 was measured using double angle Look-Locker acquisition on 3T systems. Single-shot spin-echo echo-planar imaging with fat suppression and outer-volume suppression (OVS-DWEPI) with b values of 10 and 500 s/mm2 was used for diffusion-weighted imaging. ASSESSMENT A phantom study using diluted gadolinium solutions and polyvinyl alcohol solutions was used to validate the two protocols. Regions of interest (ROIs) were manually outlined on MR images for areas of LR/NC, hemorrhage, and Fbr based on histological cross-sections. Pixel-based R1 and ADC values in the ROIs were plotted for each component. The probability density function of the plots determined the optimum contours to separate the three components in the ADC-R1 plane. The LR/NC, hemorrhage, and Fbr regions were mapped on MR images based on the above results and compared to histological results. STATISTICAL TESTS The R1 values of the phantom measurements were tested using Bland-Altman analysis. The accuracies of the MRI classification were calculated. RESULTS R1 values

Background Sclerosing pneumocytoma is a rare lung tumor that is usually recognized as a solitary nodule in the lung. Surgical removal is recommended; however, its clinical diagnosis is still an issue because it is difficult to differentiate from lung adenocarcinomas using a tiny sample obtained from biopsy. Case presentation We report a case of pulmonary sclerosing pneumocytoma located in the upper lobe of the right lung of a 34-year-old woman, which was diagnosed before surgery by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). A 3-cm irregular mass was detected by chest X-ray without any symptoms. She was referred to our hospital after being followed for 10 years in her previous clinic. During this follow-up period, the tumor had grown to 5 cm. We performed the EBUS-TBNA for the diagnosis. The histological findings obtained by EBUS-TBNA consisted of alveolar type 2-like cells that were positive for napsin A and round cells that were positive for vimentin. Based on these immunostaining results, we successfully diagnosed sclerosing pneumocytoma before surgery. Right upper lobectomy was performed, and the pathological diagnosis of the surgical specimen was also confirmed as sclerosing pneumocytoma. Conclusions We herein report a case of sclerosing pneumocytoma, which was clinically diagnosed by EBUS-TBNA and resected surgically.

Degradation of toluene gas by ozone catalytic oxidation (OZCO) by using a MnO2-based ozone decomposition catalyst (ODC) was investigated to clarify the reactive site of ODC material with O3. An optimum structure for the ODC to remove O3 and toluene were proposed. For honeycomb ODC, toluene degradation by OZCO occurred only around the entrance of the honeycomb ODC, and we expected that a thinner ODC would increase the toluene degradation efficiency. A nonwoven fabric on which ODC was immobilized was developed to decompose O3 and volatile organic compounds simultaneously. The toluene degradation ratio and the mineralization of toluene to CO2 were determined to evaluate the performance of the fabric. Furthermore, the effects of relative humidity and O3 concentration on the decomposition and mineralization ratios were also investigated with or without 254 nm UV irradiation (UV254). The fabric decomposed and mineralized toluene to CO2, even at low O3 concentrations. Although high humidity reduced the degradation ratio of toluene, UV254 irradiation improved the recovery of the degradation ratio and increased the mineralization ratio.

Tritium (T) distributions in yttrium (Y) and cobalt (Co) doped barium-zirconates (BaZrO3) were visualized by imaging plate (IP) technique using HT gas (T/H = 10−4, ∼1.3 kPa) under various exposure temperatures (623 to 1273 K) and exposure times (5 min to 16 h). Two types of specimens, BaZr0.9Y0.1O3-α (BZY) and BaZr0.955Y0.03Co0.015O3-α (BZYC), were prepared with conventional powder metallurgy: disk-shaped specimens were obtained with more than 97% of the theoretical densities. With IP method, uniform tritium distribution was found on the surface of both T-exposed specimens. The T distributions of the cross sections of the cut-in-half specimens were also examined with IP, which showed that more T was diffused into BZYC compared to BZY. The diffusivities of T and hydrogen solubility were determined by the T concentration profiles for the BZY and BZYC samples at different exposure conditions. Almost one order higher solubility and diffusivity for BZYC than BZY was found. It suggests that only a small amount sintering-aid cobalt doping along with yttrium may play a vital role of enhancement of electrochemical activity of the proton conducting BaZrO3 under HT exposure condition.

Background Obliterative bronchiolitis (OB) is a known issue during minor histocompatibility antigen (mHA) disparity during lung transplantation. This study evaluated gene expression in a murine orthotropic lung transplantation model using microarray analysis. Methods Left lungs from C57BL/10(H-2b) donor mice were transplanted into mHA-mismatched C57BL/6(H-2b) recipient mice. Three groups (OB, non-OB, and sham controls) were confirmed pathologically and analyzed. Gene expression changes in the lung grafts were determined by microarray and immunohistochemical staining, and genes were verified by quantitative PCR in the lungs and mediastinal lymph nodes (LNs). Results A total of 1343 genes were upregulated in the OB lungs compared to the sham group. Significant upregulation was observed for genes related to innate, e.g. Tlr2 and CCL3 and adaptive immunity, e.g. H2-ab1 and Il-21. Positive labeling for MHC class II antigen was observed in the bronchial epithelium of OB accompanied with B cells. We found increased Tlr2, Ccl3, H2-ab1, Il-21, Ighg3, Ifng, and Pdcd1 mRNA expression in the OB lung, and increased Il-21, Ighg3, and Pdcd1 expression in the OB LNs. Conclusions Adaptive and innate immune reactions were involved in OB after lung transplantation, and genetic examination of related genes could be used for detection of OB.

RATIONALE AND OBJECTIVES: To evaluate whether parameters from empirical mathematical model (EMM) for ultrafast dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) correlate with histological microvessel density (MVD) in invasive breast cancer. MATERIALS AND METHODS: Ninety-eight consecutive patients with invasive breast cancer underwent an institutional review board-approved ultrafast DCE-MRI including a pre- and 18 postcontrast whole breast ultrafast scans (3 seconds) followed by four standard scans (60 seconds) using a 3T system. Region of interest was placed within each lesion where the highest signal increase was observed on ultrafast DCE-MRI, and the increase rate of enhancement was calculated as follows: ΔS = (Slpost – SIpre)/SIpre. The kinetic curve obtained from ultrafast DCE-MRI was analyzed using a truncated EMM: ΔS(t)=A(1 – e(−αt)), where A is the upper limit of the signal intensity, α (min(−1)) is the rate of signal increase. The initial slope of the kinetic curve is given by Aα. Initial area under curve (AUC30) and time of initial enhancement was calculated. From the standard DCE-MRI, the initial enhancement rate (IER) and the signal enhancement ratio (SER) were calculated as follows: IER = (SIearly – SIpre)/SIpre, SER = (SIearly – SIpre)/(SIdelayed – SIpre). The parameters were compared to MVD obtained from surgical specimens. RESULTS: A, α, Aα, AUC30, and time of initial enhancement significantly correlated with MVD (r =0.29, 0.40, 0.51, 0.43, and −0.32 with p = 0.0027, p < 0.0001, p < 0.0001, p < 0.0001, and p = 0.0012, respectively), whereas IER and SER from standard DCE-MRI did not. CONCLUSION: The parameters of the EMM, especially the initial slope or Aα, for ultrafast DCE-MRI correlated with MVD in invasive breast cancer.

Extended sleeve lobectomy (ESL), which is defined as the atypical sleeve resection of more than one lobe, has been widely accepted to preserve the pulmonary function (1-3). Double-barrel anastomosis has been reported as a method of bronchial reconstruction after carinal resection; however, it is rarely applied in the reconstruction of segmental bronchi. We herein report a case in which ESL with double-barrel anastomosis of the middle lobar bronchus (MLB) and basilar bronchus (BB) was successfully applied in the treatment of a patient with centrally located lung adenocarcinoma.

There is limited evidence of parametric MR mapping to characterize carotid plaques associated with cerebral ischemic events.To explore the apparent diffusion coefficients (ADCs) and longitudinal relaxation rates (RTwelve patients who underwent carotid endarterectomy.RA phantom study using diluted gadolinium solutions and polyvinyl alcohol solutions was used to validate the two protocols. Regions of interest (ROIs) were manually outlined on MR images for areas of LR/NC, hemorrhage, and Fbr based on histological cross-sections. Pixel-based RThe RRThe combination of ADC and R1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:1657-1667.

In this paper, we introduce our solution to the Challenge-1 of the MS-Celeb-lM challenges which aims to recognize one million celebrities. To solve this large scale face recognition problem, a Multi-Cognition Softmax Model (MCSM) is proposed to distribute training data to several cognition units by a data shuffling strategy. Here we introduce one cognition unit as a group of independent softmax models, which is designed to increase the diversity of the one softmax model to boost the performance for models ensemble. Meanwhile, a template-based Feature Retrieval (FR) module is adopted to improve the performance of MCSM by a specific voting scheme. Moreover, a one-shot learning method is applied on collected extra 600K identities due to each identity has one image only. Finally, testing images with lower score from MCSM and FR are assigned new labels with higher score by merging one-shot learning results. Extensive experiments on the MS-Celeb-1M testing set demonstrate the superiority of the proposed method. Our solution ranks the first place in both two settings of the final evaluation and outperforms other teams by a large margin.

The brain is a frequent site of metastases from non-small-cell lung cancer (NSCLC). We analyzed the frequency of brain metastases (BMs) from NSCLC in the era of magnetic resonance images, and evaluated the correlation between epidermal growth factor receptor (EGFR) mutations and BMs among East Asian patients. Frequency, number, and size of BMs, and survival of 1,127 NSCLC patients were retrospectively reviewed. Mutation status of EGFR was evaluated in all cases, and its association with BMs was statistically evaluated. EGFR mutations were found for 331 cases (29.4 %). BM was the cause of primary symptoms for 52 patients (4.6 %), and found before initiation of treatment for 102 other patients (9.1 %); In addition to these 154 patients, 107 patients (9.5 %) developed BMs, giving a total of 261 patients (23.2 %) who developed BMs from 1,127 with NSCLC. BM frequency was higher among EGFR-mutated cases (31.4 %) than EGFR-wild cases (19.7 %; odds ratio: 1.86; 95 % confidence interval (CI) 1.39–2.49; P

We have developed a TiO2-assisted reactor that improved the UV light penetration into the solution during the photocatalytic decomposition of isopropyl alcohol (IPA). Increasing the UV penetration enhanced the decrease in the concentration of acetone, which is the main IPA decomposition product, and the total organic carbon. However, it did not affect the decrease in IPA concentration. Charging the solution with O3 microbubbles significantly increased mineralization for the first 5 h of the reaction. Our results can be used to improve the efficiency of UV sources and develop an ecologically friendly, practical wastewater treatment for IPA.

A 68-year-old woman who presented with a left axillary mass was admitted. A computed tomography scan showed swelling ofthe left axillary and supraclavicular lymph nodes, but magnetic resonance imaging(MRI)and fluorodeoxyglucose positron emission tomography(FDG-PET)did not reveal these primary sites. Histological findings of the axillary mass revealed a HER2-positive adenocarcinoma. We diagnosed the patient with axillary nodal metastasis ofadenocarcinoma ofan unknown primary site and treated her with neoadjuvant chemotherapy including paclitaxel and trastuzumab followed by doxorubicin and cyclophosphamide. The lesions almost disappeared after 3 courses of chemotherapy and she showed a pathologically complete response(CR)after surgery. The patient has been recurrence-free since the operation owing to treatment with adjuvant trastuzumab.

The objective of this study was to evaluate a resolution recovery (RR) method using a variety of simulated human brain [11C]raclopride positron emission tomography (PET) images. Simulated datasets of 15 numerical human phantoms were processed by a wavelet-based RR method using an anatomical prior. The anatomical prior was in the form of a hybrid segmented atlas, which combined an atlas for anatomical labelling and a PET image for functional labelling of each anatomical structure. We applied RR to both 60 min static and dynamic PET images. Recovery was quantified in 84 regions, comparing the typical 'true' value for the simulation, as obtained in normal subjects, simulated and RR PET images. The radioactivity concentration in the white matter, striatum and other cortical regions was successfully recovered for the 60 min static image of all 15 human phantoms; the dependence of the solution on accurate anatomical information was demonstrated by the difficulty of the technique to retrieve the subthalamic nuclei due to mismatch between the two atlases used for data simulation and recovery. Structural and functional synergy for resolution recovery (SFS-RR) improved quantification in the caudate and putamen, the main regions of interest, from −30.1% and −26.2% to −17.6% and −15.1%, respectively, for the 60 min static image and from −51.4% and −38.3% to −27.6% and −20.3% for the binding potential (BPND) image, respectively. The proposed methodology proved effective in the RR of small structures from brain [11C]raclopride PET images. The improvement is consistent across the anatomical variability of a simulated population as long as accurate anatomical segmentations are provided.

Segregation in granular materials has been studied by means of Monte Carlo simulation. The mechanism of segregation in a binary mixture of particles with different sizes and densities has been investigated for shaking and rotating processes in two-dimensional space. From the simulations we have obtained the segregation diagrams for shaking and rotating. These diagrams show what type of segregation occurs in a binary mixture with given values of the size ratio and the density ratio. From the diagrams we can also know what conditions are required to avoid segregation and mix uniformly a mixture of particles with different sizes and densities by the shaking and fast rotating processes. It is also shown that in the shaking process there is a critical size-ratio above which large-sized particles always segregate upward irrespective of the density ratio. Some implications of the segregation diagrams for shaking and rotating obtained by our simulations are discussed with consideration for real granular materials.

Purpose Accurate longitudinal relaxation time (T₁) of arterial blood is important in evaluating blood flow in tissue by arterial spin labeling magnetic resonance (MR) imaging. Few studies have reported the T₁ of human arterial blood in vivo, especially using 3-tesla MR imaging. T₁ values of human venous blood in vivo have been reported, but they differ from those measured in vitro. We aimed to evaluate the accurate T₁ of human arterial blood in vivo. Methods We measured T₁ values of blood in 10 healthy volunteers in vivo using an inversion-recovery fast gradient-echo sequence and 3-tesla MR imaging unit. We also measured hematocrit (Hct) values of venous blood samples. After nonselective application of the inversion pulse using a body coil, we obtained MR imaging signals of arterial blood in the abdominal aorta. Similarly, we measured the signals of venous blood in the internal jugular vein. Inversion times varied between 200 and 5000 ms for imaging of the abdominal aorta and 200 and 2500 ms for imaging of the jugular vein. We also acquired signals without the inversion pulse. We estimated T₁ values from the data by nonlinear least squares fitting of a 3-parameter model. Results The T value (mean±standard deviation) of arterial blood was 1779±80 ms and of venous blood, 1694±77 ms. The average Hct value was 0.47. The R₁ (=1/T₁) of arterial blood was related to the Hct value as: R₁=(0.59±0.16)Hct+(0.29±0.07) (mean±standard error) s⁻¹. For the venous blood, R₁=(0.70±0.11)Hct+(0.27±0.05) s⁻¹. Conclusion We observed a T₁ of human arterial blood in vivo of 1779±80 ms at a mean hematocrit value of 0.47 as determined by 3T MR imaging; an even longer T₁ value is expected with a hematocrit value less than 0.47.

Objective: The purpose of this study was to evaluate the usefulness of z-score mapping method on neuroradiologists' performance in quantification of the extent of hypoattenuation regions of hyperacute stroke on unenhanced computed tomographic (CT) images by using the Alberta Stroke Programme Early CT Score system. Methods: Twenty-one patients with infarction (

Photocatalytic reactions in the gas phase have a number of disadvantages including the adverse effects of relative humidity, the emission of decomposition intermediates at the reactor exit and the deactivation of the photocatalyst surface by decomposition intermediates. In this study, these disadvantages can be overcome using a novel photocatalytic reaction system. Volatile organic compound (VOC) gases were decomposed at the bubble interface in a TiO 2 suspension by using TiO 2 photocatalysis in the heterogeneous liquid-bubble (LB) phase since the intermediates dissolve into water and then are continuously decomposed regardless of humidity. Toluene, p -xylene, styrene and formaldehyde were chosen as model VOC gases to investigate photocatalytic reactivity in the LB phase. The removal ratio of VOC gases in the LB phase was equal to or greater than that in the gas phase, although the reactivity in the LB phase depended on the reaction rate of OH radicals and the hydrophobicity of the VOC gases. The reaction in the LB phase also depended on the wavelength and intensity of UV light. Specifically, the removal and mineralization ratios were improved by using shorter wavelengths of UV irradiation. Finally, as a trial experiment, we applied the microbubble technique to this system. When VOC gases were introduced into the system as microbubbles, VOC gas was effectively removed and high removal ratios were obtained regardless of the wavelength and intensity UV light.

Chemical reactions on the surface of building materials can lead to secondary emissions from these materials that influence indoor air quality. Many studies have been made on the physical processes that influence material emissions. However, there are only a few studies on secondary emissions resulting from exposure of building material surfaces to ozone or ultraviolet (UV) irradiation. Therefore, this study was aimed at elaborating on the emission of chemicals resulting from chemical reactions initiated by the exposure of the surface of flooring materials to ozone or UV irradiation. The laboratory tests were conducted to estimate gas-phase emissions from the flooring materials when they were exposed to ozone or various kinds of light irradiation (infrared, sunlight, UV-A and UV-B lamps). The infrared and sunlight lamps significantly increased the temperature of the test specimens and, in turn, increased the emission rate for various organic compounds. The flooring materials used in this study had been treated with UV-cured surface coatings during their manufacturing. As a result, when exposed to UV irradiation, chemical transformations occurred resulting in the emission of a number of secondary products, including formaldehyde, acetaldehyde, cyclohexanone and benzaldehyde. Ozone reacted with chemicals present in the flooring materials to increase the emission rates of formaldehyde and acetaldehyde. Hence, the exposure of ozone and UV irradiation increased the secondary emissions of formaldehyde, even though the low formaldehyde emission type of flooring material was employed.

BACKGROUND AND PURPOSE: Early accurate diagnosis of brain metastases is crucial for a patient's prognosis. This study aimed to compare the conspicuity and detectability of small brain metastases between contrast-enhanced 3D fast spin-echo (sampling perfection with application-optimized contrasts by using different flip angle evolutions [SPACE]) and 3D gradient-echo (GE) T1-weighted (magnetization-prepared rapid acquisition of GE [MPRAGE]) images at 3T. MATERIALS AND METHODS: Sixty-nine consecutive patients with suspected brain metastases were evaluated prospectively by using SPACE and MPRAGE on a 3T MR imaging system. After careful evaluation by 2 experienced neuroradiologists, 92 lesions from 16 patients were selected as brain metastases. We compared the shorter diameter, contrast rate (CR), and contrast-to-noise ratio (CNR) of each lesion. Diagnostic ability was compared by using receiver operating characteristic (ROC) analysis. Ten radiologists (5 neuroradiologists and 5 residents) participated in the reading. RESULTS: The mean diameter was significantly larger by using SPACE than MPRAGE (mean, 4.5 ± 3.7 versus 4.3 ± 3.7 mm, P = .0014). The CR and CNR of SPACE (mean, 57.3 ± 47.4%, 3.0 ± 1.9, respectively) were significantly higher than those of MPRAGE (mean, 37.9 ± 41.2%, 2.6 ± 2.2; P < .0001, P = .04). The mean area under the ROC curve was significantly larger with SPACE than with MPRAGE (neuroradiologists, 0.99 versus 0.88, P = .013; residents, 0.99 versus 0.78, P = .0001). CONCLUSIONS: Lesion detectability was significantly higher on SPACE than on MPRAGE, irrespective of the experience of the reader in neuroradiology. SPACE should be a promising diagnostic technique for assessing brain metastases.

The use of an adaptive filter for CT images is becoming a common procedure and is said to reduce image noise while preserving sharpness and helping to reduce the required X-ray dose. Although many reports support this view, the validity of such evaluations is arguable. When the linearity of a system is in question, physical performance indexes should be measured under conditions similar to those of clinical use. Evaluations of diagnosis using clinical images may be fallible because the non-filtered image used as the reference might not have been optimally reconstructed. We have chosen simple, but commonly used, adaptive filters for our evaluation. As a reference for comparing performance, we designed linear filters that best approximate the noise characteristics of the adaptive filters. MTF is measured through observation of the edge-spread function. Clinical abdominal images are used to compare the performance of adaptive filters and linear filters. We conclude that the performance of the type of adaptive filter we have chosen is virtually the same as that of the linear filter, as long as the image quality of soft tissues is our interest. Both the noise SD and MTF are virtually the same if the contrast of the object is not substantially higher than 150 HU. Images of soft tissues obtained with the use of adaptive filters are also virtually the same as those obtained by linear filters. The edge-preservation characteristic of this adaptive filter is not observable for soft tissues.

Temporal evolution of the water apparent diffusion coefficients (ADC) parallel (ADC parallel) and perpendicular (ADC perpendicular) to the human white matter tract following ischemia has not been investigated systematically. We attempted to quantify the evolution of ADC parallel and ADC perpendicular and examine whether it can be interpreted by a model of ischemic edema.We retrospectively selected 53 patients with ischemic lesions involving the posterior limb of the internal capsule (PLIC) and placed regions of interest in the right and left PLIC on ADC maps. We performed regression analysis of lesion-to-contralateral ratios of ADC parallel and ADC perpendicular against the time (t = 1-1600 h) from onset. We then fitted the estimated time courses of ADC parallel and ADC perpendicular obtained from the analysis to a model of nerve tissue composed of cylinders (axons) and spheres corresponding to isotropic structures, particularly focal cytoplasmic swellings of glial cells and axons seen in ischemic white matter.The evolution of ADC perpendicular and ADC parallel differed. The estimated time course of ADC parallel in microm(2)*ms(-1) was 0.64 + 0.88 exp (-0.24t) for 1t54 h and 0.00059t + 0.61 for tor= 54 h (contralateral normal value, 1.52). That of ADC perpendicular was 0.19-0.063 exp (-0.24t) for 1t54 h and 0.00040t + 0.17 for tor=54 h (normal value 0.22). The model fitted to these values showed that the volume of the cylinders decreased, that of the spheres increased, and extracellular volume changed little from one hour to approximately one day after stroke onset.In the human PLIC, ADC parallel continued to decrease from one hour to a few days after stroke onset, and ADC perpendicular tended to increase. The temporal evolution could be interpreted by progression of the focal cytoplasmic swelling of glial cells and axons previously observed in animal studies.

This study aims at discussing the methods which could measure effectively the ionic compounds using Si surface on the condition of electric field. Due to the difficulty of measuring the ionic and non-ionic compounds separately, the chemical and physical characteristics are still unknown. As the first step of the study, the authors carried out experiments to analyze the airborne compounds under an electric field with various field strengths. For the experimental apparatus, the clean chamber was set up with the corona discharge type ionizer, discharger of chemical component, witness plate for testing and tool for setting electric field. The exposure experiment was performed to select the test compounds and the adsorbent. As the test chemicals for exposure experiments, toluene and LMCS (Low-molecular-weight cyclo-dimethyl-siloxane) were used. Shattered or cut silicon wafer was mainly used for adsorbent of chemical components. GC/MS (Gas Chromatograph Mass Spectrometer) was used to analyze ionic compounds. The experiments were conducted using the conditions of ionizer (+, -, off), and electric field (+, -, off) as the basis. For the results of the exposure experiment, which was required in order to select the correct test compounds and the test surface, comminuted silicon wafer maintain a higher possibility of adsorption compared to the cut silicon wafer in regards to processed silicon product. Results of the measurement using comminuted Si-wafer surface which was charged with same polarity of ionic compounds, the increase in LMCS'adsorption was confirmed in comparison with the results of the measurement within the non charged condition.

There are various emission sources of chemical contaminants, such as volatile organic compounds (VOCs) and ozone and particulate matter. This report is a study into the indoor air of a room containing either a laser printer/ink-jet printer, and the air contaminations were monitored for VOCs, ozone and ultrafine particle. The result confirmed an increase in the concentration of ozone and ultrafine particle numbers in the printing processes of the printer. The emission of VOCs and ozone were measured by the use of a test chamber. The chamber concentrations of styrene, xylenes and ozone were increased in printing process of the laser printer, and pentanol was detected from the ink-jet printer. The results suggest that an office or residential printer may be a source of indoor air contamination. It is necessary for emission from printers to monitor not only VOCs and particle but also ultrafine particles and other contaminants in indoor air.

背景．自然気胸を初発とする肺癌は稀であり，自然気胸を契機に発見された微小肺癌症例を経験したので報告する．症例．53歳，男性．2006年5月，呼吸困難感を自覚し，前医を受診した．左自然気胸と診断され，当院紹介となり，胸腔ドレナージが施行された．自然気胸は改善したが，胸部CTにて左S1＋2胸膜直下に胸膜陥入を認め，周囲にGGOを伴った径10 mmの結節影を認めた．2ヶ月の経過観察にて結節影は消退せず，充実部分の増大および胸膜陥入の増悪傾向がみられたため，同年7月胸腔鏡下肺生検を施行し，肺腺癌と診断した．左肺上大区域切除およびリンパ節郭清術を引き続き行い，病理組織学的には腫瘍径7×7×5 mmの，高分化型腺癌pT1N0M0 stage IAと診断した．結論．近年，CT画像の向上とともに微小肺癌が発見される機会が増えつつあり，自然気胸症例といえどもCTの画像評価は，腫瘍性病変を見落とさないように慎重に行うべきである．周囲にGGOを伴う結節性小型病変は，悪性である可能性があり，経過観察にて消退しない場合，肺癌の可能性を念頭において精検すべきである．

Primary intrapulmonary thymomas (PITs), which are intrapulmonary tumors without an associated mediastinal component, are very rare. The diagnosis of a PIT can be difficult. Here, we report two cases of resected PITs that were difficult to differentiate from other lung tumors. The patients, of a 62-year-old man and a 64-year-old woman, had no significant symptoms and were both referred to our hospital due to the presence of an abnormal shadow on chest computed tomography (CT). The patients underwent (18)F-fluorodeoxyglucose positron emission tomography-CT (FDG-PET/CT) and subsequently tumor excision. A PIT was confirmed histopathologically in the surgical specimens from both patients. In one case, the tumor consisted of a type A thymoma without abnormal FDG uptake. In the other case, the tumor consisted of a type B2 thymoma presenting with weak FDG uptake. This report thus documents two cases of PITs with different histopathologic and FDG-PET/CT findings. Thoracoscopic surgery is essential in the differential diagnosis between PITs and other lung tumors.

The noise power spectrum (NPS), an index for noise evaluation, represents the frequency characteristics of image noise. We measured the NPS in PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) magnetic resonance (MR) imaging, a nonuniform data sampling technique, as an initial study for practical MR image evaluation using the NPS. The 2-dimensional (2D) NPS reflected the k-space sampling density and showed agreement with the shape of the k-space trajectory as expected theoretically. Additionally, the 2D NPS allowed visualization of a part of the image reconstruction process, such as filtering and motion correction.