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We developed a new exposure system to irradiate microwaves locally on a rabbit eye using a small coaxial-to-waveguide adapter filled with low-loss dielectric material as an antenna. A numerical rabbit model was also developed using X-ray computer tomography images, and the specific absorption rates (SARs) in the rabbit, especially in the eye, were analyzed with the finite-difference time-domain method. The temperature elevation in the exposed eye was also evaluated by solving a bioheat equation. Our exposure system can generate incident power density of 15 mW/cm2 at the surface of a rabbit eye with input power of 1 W. When the incident power density on the rabbit eye is 300 mW/cm2 , average SAR over the exposed eye and the whole body were approximately 108 and 1.8 W/kg, respectively. The exposure system can realize localized exposure to the eye with the ratio of exposed-eye averaged SAR to the whole-body averaged SAR was 60. The developed exposure system can achieve high-intensity exposure such as the threshold of cataracts, i.e., the eye-averaged SAR over 100 W/kg or the lens temperature over 41 degC with the incident power density of 300mW/cm2 without significant whole-body thermal stresses

The assessment of impacts of pastoral herds to the fringing wetlands of Lake Victoria in Magu district in Mwanza region was carried out in 1999/2000. Lamadi village located along Speke Gulf of Lake Victoria was chosen. The main farming systems in the area are agriculture, agro-pastoralism, and pastoralism. The wetlands are heavily used for livestock grazing during the dry season. Since 1990s the area has been experiencing a high influx of immigrant pastoral herds from drought prone districts. The increasing livestock numbers have led into serious degradation of wetlands. The type of damages includes: soil erosion, loss of vegetation cover and deforestation. This lead to pollution of Lake Victoria along the Speke gulf in particular as the wetlands was buffering a lot of pollutants from the catchments. The range condition at Lamadi was rated fair. The carrying capacity of rangelands was estimated at 3.57–6.75 ha/LU and the wetlands were seriously degraded causing heavy soil erosion and environmental pollution during rainy season. It was recommended to raise people’s awareness on conservation of environment and mobilise communities to take responsibility on management of the environmental resources.

Purpose: There have been few reports for independent dose verification for Tomotherapy. We evaluated the accuracy and the effectiveness of an independent dose verification system for the Tomotherapy. Methods: Simple MU Analysis (SMU, Triangle Product, Ishikawa, Japan) was used as the independent verification system and the system implemented a Clarkson-based dose calculation algorithm using CT image dataset. For dose calculation in the SMU, the Tomotherapy machine-specific dosimetric parameters (TMR, Scp, OAR and MLC transmission factor) were registered as the machine beam data. Dose calculation was performed after Tomotherapy sinogram from DICOM-RT plan information was converted to the information for MU and MLC location at more segmented control points. The performance of the SMU was assessed by a point dose measurement in non-IMRT and IMRT plans (simple target and mock prostate plans). Subsequently, 30 patients’ treatment plans for prostate were compared. Results: From the comparison, dose differences between the SMU and the measurement were within 3% for all cases in non-IMRT plans. In the IMRT plan for the simple target, the differences (Average±1SD) were −0.70±1.10% (SMU vs. TPS), −0.40±0.10% (measurement vs. TPS) and −1.20±1.00% (measurement vs. SMU), respectively. For the mock prostate, the differences were −0.40±0.60% (SMU vs. TPS), −0.50±0.90% (measurement vs. TPS) and −0.90±0.60% (measurement vs. SMU), respectively. For patients’ plans, the difference was −0.50±2.10% (SMU vs. TPS). Conclusion: A Clarkson-based independent dose verification for the Tomotherapy can be clinically available as a secondary check with the similar tolerance level of AAPM Task group 114. This research is partially supported by Japan Agency for Medical Research and Development (AMED)

Several clinical trials and in vivo animal experiments have suggested that blockade of angiotensin receptor type 1 (AT(1)) improves ischaemic outcomes. However, the mechanism(s) underlying these effects has not been elucidated. Here, we have investigated the protective effects of pretreatment with AT(1) receptor antagonists, losartan or telmisartan, against ischaemic insult to neurons in vitro.Primary rat neuron-astrocyte co-cultures and astrocyte-defined medium (ADM)-cultured pure astrocyte cultures were prepared. Ischaemic injury was modelled by oxygen-glucose depletion (OGD) and lactate dehydrogenase release after OGD was measured with or without AT(1) receptor antagonists or agonists (L162313), AT(2) receptor antagonist (PD123319) or agonist (CGP-42112A) pretreatment, for 48 h. Activity of glutamate transporter 1 (GLT-1) was evaluated by [(3)H]-glutamate uptake assays, after AT(1) receptor agonists or antagonists. Immunoblot and real-time PCR were used for analysis of protein and mRNA levels of GLT-1.AT(1) receptor agonists augmented OGD-induced cellular damage, which was attenuated by AT(1) receptor antagonists. AT(1) receptor antagonists also suppressed OGD-induced extracellular glutamate release, reactive oxygen species production and nitric oxide generation. GLT-1 expression and glutamate uptake activity were significantly enhanced by AT(1) receptor antagonists and impaired by AT(1) receptor agonists. AT(1) receptor stimulation suppressed both ADM-induced GLT-1 protein expression and mRNA levels. AT(1)b receptor knock-down with siRNA enhanced GLT-1 expression. In postnatal (P1-P21) rat brains, protein levels of GLT-1 and AT(1) receptors were inversely correlated.Suppression of AT(1) receptor stimulation induced GLT-1 up-regulation, which ameliorated effects of ischaemic injury.

Glutamate excitotoxicity may be involved in ischaemic injury to the CNS and some neurodegenerative diseases, such as Alzheimer's disease. Donepezil, an acetylcholinesterase (AChE) inhibitor, exerts neuroprotective effects. Here we demonstrated a novel mechanism underlying the neuroprotection induced by donepezil.Cell damage in primary rat neuron cultures was quantified by lactate dehydrogenase release. Morphological changes associated with neuroprotective effects of nicotine and AChE inhibitors were assessed by immunostaining. Cell surface levels of the glutamate receptor sub-units, NR1 and NR2A, were analyzed using biotinylation. Immunoblot was used to measure protein levels of cleaved caspase-3, total NR1, total NR2A and phosphorylated NR1. Immunoprecipitation was used to measure association of NR1 with the post-synaptic protein, PSD-95. Intracellular Ca(2+) concentrations were measured with fura 2-acetoxymethylester. Caspase 3-like activity was measured using enzyme substrate, 7-amino-4-methylcoumarin (AMC)-DEVD.Levels of NR1, a core subunit of the NMDA receptor, on the cell surface were significantly reduced by donepezil. In addition, glutamate-mediated Ca(2+) entry was significantly attenuated by donepezil. Methyllycaconitine, an inhibitor of alpha7 nicotinic acetylcholine receptors (nAChR), inhibited the donepezil-induced attenuation of glutamate-mediated Ca(2+) entry. LY294002, a phosphatidyl inositol 3-kinase (PI3K) inhibitor, had no effect on attenuation of glutamate-mediated Ca(2+) entry induced by donepezil.Decreased glutamate toxicity through down-regulation of NMDA receptors, following stimulation of alpha7 nAChRs, could be another mechanism underlying neuroprotection by donepezil, in addition to up-regulating the PI3K-Akt cascade or defensive system.

The purpose of this paper is to propose a new approach to detecting obstacles using a single camera mounted on a vehicle when the vehicle is backing or turning round at an intersection at a low speed. Using restrictions among feature point locations and their optical flows in geometrically converted top-view images, ground-movement information can be estimated. Our approach compensates for the ground movement between consecutive top-view images using the estimated ground-movement information and computes the difference image between the previous compensated top-view image and the current top-view image. Finally, a new angle histogram-based algorithm is processed to extract obstacle regions using the difference image. The actual in-vehicle experimental results show that our proposed approach has tolerance for various changing illumination conditions and different road textures.

The aim of this study was to determine how the fimbriae of Porphyromonas gingivalis function in plaque formation.We used scanning electron microscopy to examine aggregates and hemaggregates of fimbria-rich ATCC33277 (parent) and fimbra-poor OZ6301C (pgmA-knockout, mutant) strains of P. gingivalis. We also assessed the hemagglutination activity of the two strains as an indicator of P. gingivalis adhesiveness.Aggregates of P. gingivalis were composed of bacterial chains and clusters. Rich fimbriae projecting from cells of the parent strain tended to bunch and form a dense meshwork among bacterial cells. In contrast, cells of the mutant strain projected fewer fimbriae and the meshwork was looser. Hemaggregates including cells of the parent strain contained a detached, dense fimbrial meshwork that adhered to erythrocytes. Hemaggregates comprising cells of the mutant strain included bacterial chains and clusters that adhered to erythrocytes by shorter fimbriae than those of the parent strain. The hemagglutination titer of the parent strain was 10-fold higher than that of the mutant strain, although the number of fimbriae per cell of the parent strain was only double that of the mutant strain.The results indicate that P. gingivalis adhesiveness is prominently enhanced by the dense fimbrial meshwork. Thus, the virulence of P. gingivalis is increased by the presence of rich fimbriae.

This article discusses face and hand sign recognition and its applications. We have already proposed a method that can recognize faces and hand signs using hierarchical discriminant analysis. Here, we implement this method on a laptop computer and develop a real-time system that can control home appliances by recognizing faces and hand signs. Our system can control various appliances in the home by remote control. Moreover, since our system can recognize the user, it can assign distinct commands to the hand signs of each user and limit the appliances and functions that users can control.

Our purpose is to clarify the significance of viewing time while fixating on a certain point of an image. A new sight-line displacement analyzer has been developed that limits the subject's viewing time by inserting a masking pattern in his focusing area. Eye movement was analyzed while the subject counted circles in a pattern filled with distractors. The mean fixation duration during this counting, which corresponds to the counting processing time, was about 350 msec. Counting was executed fairly accurately when a mask was presented at 66 msec after fixation was detected. Results indicate that visual information can be acquired in less than 66 msec.

Real-time human detection is an important part in a surveillance system using computer vision. In this paper, a real-time face and head detection method is proposed for such human detection. The method has an advantage of detecting peoples who are not facing a camera, by detecting their heads. It employs four directional features (FDF) and linear discriminant analysis in order to save computation cost for scanning and classification. Since FDF represents edge directional information in low resolution, it is resistive to changes in lighting conditions and scales. The proposed method was evaluated through an experiment using 26 video scenes. The results of experiment were 83.6% (46/55) for human detection rate, and 84.6% (1048/1239) for reliability of detection. The human detection system implemented with the proposed method runs on a PC at approximately over 10 fps for VGA input with motion detection.

For most of the existing pointing systems proposed in the past, the pointing target was limited to a specific surface in the space, usually an object on a 2-D screen. This paper presents a new solution for estimating the pointing target inside a 3-D space, such as a room. A special set of stereo cameras acquires images and depth maps from the entire environment. Using a background subtraction method, our system detects the foreground pixels, analyzes them and extracts the user's face and hand regions. Considering that the pointing direction is the straight line connecting the face and the hand, the pointing target can be seen as the intersection of that line with the 3-D model of the environment, allowing the calculation and the display of the person's viewpoint.

In this paper, we propose a novel method using an adaptive discriminant space to identify people's faces from various directions. The adaptive discriminant space that is constructed from the candidates' facial images optimally distinguishes between faces among certain candidate.. A principle method of our research gradually limits the classification of categories by using face direction estimation and recognition. Both the face direction estimation method and the face recognition method are appearance-based methods that employ linear discriminant analysis (LDA) on the four-directional features (FDF). First, our method chooses the candidates using a hierarchical combination of face direction estimation and recognition. Next, face direction is estimated exactly by each candidate's discriminant space of face direction estimation. Finally, our method creates a new discriminant space from the candidates' facial images selected from the results of the face direction estimation procedure. Limiting variations of a face direction can strengthen a face recognition discriminant space Using the adaptive discriminant space, the candidates can be selected optimally. Experiments showed that our method improved our accuracy rate 1.2 % to 98.8 %, achieved by hierarchical face recognition of 105, 000 images from 150 subjects facing 35 different directions.

For marketing research, it is important to know what customers are interested in, and to evaluate the effectiveness of advertisements. Nowadays, marketing information regarding the evaluation of advertisements is mainly obtained from researchers' activities, which are difficult and time consuming. The research activities can be improved by use of surveillance systems with computer vision technologies. In this paper, a marketing information system that detects customers' attention behavior with computer vision is proposed. Cameras are attached to the display that presents advertisements in the system. Thus, the proposed method mainly consists of frontal face detection with "Four-Directional Features (FDF)" and calculating the spatial position of a face by stereovision. It is supposed that this system enables long time surveillance and uniform evaluation of presented advertisements. In addition, it is easy to distinguish which advertisements attract the most attention. Experimental results show that this system can detect attention behavior.

This paper describes a system that detects the gaze points of customers looking at advertisements that have been presented on a monitor for marketing research. The proposed system detects the gaze points without restriction of customers using multiple cameras attached with each target. Using our system, the target that the customers were gazing at could be estimated, and the ratio of gaze points is countable for each advertisement.

In this paper we propose a TV control system for aged and bedridden people. We have been constructing the interface, which changes TV channels and operates volume controls using pose recognition. However, users were required to wear a short-sleeved shirt for recognition of poses using skin color regions as arms. To allow the wearing of long sleeves, we improve our system to introduce the relation of the position of higher local auto correlation features to identify the pose. First, face and hand regions of the user are detected using skin color from the input image. Since it assumed that the width of a face region should be larger than arms, the face region is decided from the detected skin color regions using an erosion operation. After detecting the face region, a pose recognition area that is decided on the basis of face position is divided into 9 (3 /spl times/ 3) regions. Features are extracted from the 6 areas because the arms appear within the 6 areas. Using our algorithm, our system can recognize poses even if the user wears a long-sleeved or short-sleeved shirt.

This paper describes the measurement system of head and eye movement for analyzing brain function. This system is able to measure the movement of the gaze in space in real time by converting the degree of head movement to that of eye movement. It superimposes this calculation result onto the image seen by the subject. For analysis of brain function, such us a comparative study of the gaze movements of Alzheimer's disease patients and healthy people, this system provides two methods. One is for movement data of the head and eyes while the subject is tracking changes in targets, and the other is for minute eye movement data while the subject stares at a fixed point.

In this paper, we propose an estimate of face orientation by detecting the eyes and mouth on a facial image. Our purpose is to develop a new vision-based human interface technology that uses face orientation to interact with humans. Our algorithm samples a range of skin colors and dynamically updates feature templates from the current input image. In addition, we estimate face orientation from the relationship between the detected facial features' positions. As a result, our system determined the correct location of both the eyes and the mouth for all four subjects more than 94% of the time.

We propose a multi-camera system that can focus on faces and hand gestures for recognition. The system consists of four cameras. Two fixed cameras are used as a stereo system to estimate face and hand (F&H) positions. F&H regions are detected by a standard skin color method. The distances of the targets are then estimated. The positions and sizes of targets are evaluated for tracking between consecutive frames. The other two cameras perform tracking of such targets as faces and hands. If a target is not the appropriate size for recognition, the tracking cameras acquire its zoomed image. We propose a hierarchy linear discriminant analysis that distinguishes between faces and hands on the first step, and then recognizes face and hand gestures in each discriminant space by using four directional features. The experimental results show that our system could distinguish between faces and hands, as well as recognize face and hand gestures by using the four directional features.

This paper proposes a hierarchical method of face direction estimation and face recognition based on the "four directional features" with linear discriminant analysis. We expand this method to an approach with multiple cameras. Experiments show that our proposed method can achieve a recognition rate 92.6% for the faces that took in the extent of about 300/spl deg/ and the co-operation of multiple cameras can recognize occluded face images.

We propose a multi-camera system that can track multiple human faces and hands as well as focus on face and hand gestures for recognition. Our current system consists of four cameras. Two fixed cameras are used as a stereo system to estimate face and hand positions. The stereo camera detects faces and hands by a standard skin color method we propose. The distances of the targets are then estimated. Next to track multiple targets, we estimate the positions and sizes of targets between consecutive frames. The other two cameras perform tracking of such targets as faces and hands. If a target is not the appropriate size for recognition, the tracking cameras acquire its zoomed image. Since our system has two tracking cameras, it can track two targets at the same time. To recognize faces and hand gestures, we propose four directional features by using linear discriminant analysis. Using our system, we experimented on human position estimation, multiple face tracking, and face and hand gesture recognition. These experiments showed that our system could estimate human position with the stereo camera and track multiple targets by using target positions and sizes even if the persons overlapped with each other. In addition, our system could recognize faces and hand gestures by using the four directional features.

The treatment of sidebranch ostial lesions jailed after stent implantation is challenging. We report a case of successful Cutting Balloon angioplasty through stent struts of a severe, elastic sidebranch ostial lesion. Three-day follow-up angiography showed no recurrent stenosis. The patient was discharged with complete resolution of chest discomfort and the post-hospitalization course was uneventful. Cutting Balloon angioplasty may be an optimal strategy for the treatment of elastic ostial lesions in smaller vessels that are suboptimal for stenting. The long-term benefits of using a Cutting Balloon for the treatment of sidebranch ostial lesions are still to be determined.

We studied a 29-year-old Japanese male patient with factor XI deficiency; we also studied his parents and one sibling. Factor XI coagulation activity and antigen levels were extremely low (less than 1% of normal level) in both the patient and his brother, and they were half the normal levels in both parents. Sequence analysis of all 15 exons and the exon-intron boundaries of the factor XI gene amplified by polymerase chain reaction revealed a nonsense mutation in exon 8 (Gln263--Stop). Although the parents are first cousins, the mutation was unexpectedly heterozygous in all the family members except the father, who showed the homozygous wild type, indicating that this mutation alone was not sufficient to account for the factor XI deficiency. To explore the genetic abnormality in the father, we analyzed allele-specific expression of the platelet factor XI gene using reverse transcription-polymerase chain reaction and subsequent restriction enzyme digestion. As a result, gene expression from only one allele was severely impaired in the father. This result implies an additional mutation in some regulatory element of the factor XI gene from paternal inheritance. We concluded that the factor XI deficiency of the patient was caused by compound heterozygous genetic abnormalities.

A 71-year-old woman underwent radical resection in May 1994 for a mediastinal mass invading the anterior chest wall. Histopathological examination revealed adenosquamous cell carcinoma. She was treated with postoperative chemotherapy including 5-fluorouracil (5-FU) and 4'-D-tetrahydropyrayl-doxorubicin (THP), based on in vitro chemosensitivity testing (CST), by MTT assay, using a surgical specimen. In December 1994, a recurrent tumor was detected on the left anterior chest wall and the patient received two courses of 5-FU, THP and methotrexate (MTX). The size of the chest-wall tumor decreased 25%. In July 1995, the patient had involvement of the left axillary lymph node and brain metastases in addition to the mass on the chest wall. Therefore, cisplatin, 5-FU and MTX were selected as treatment agents, based on CST using a metastatic axillary lymph node. After two courses of these agents, chest computed tomography showed a 91% reduction in the size of the chest wall tumor. Radiation was administered for the brain metastasis. In March 1997, the patient died of thymic carcinoma.

A weld metal zone composed of two or more weld metals with different creep properties is proposed as an approach to produce welded joints with well balanced performance in terms of creep lifetime and ductility. Type 304 steel was welded by depositing a 308L and/or a 308 wire. The resulting weld metal zones are composed of a ’soft’ weld metal with high ductility and 0-to-100 vol. % of a ’hard’ one with an extended creep lifetime but low ductility. The creep tests suggest that the creep behavior of a welded joint may be controlled to obtain an optimum balance between its time-to-rupture and elongation.

A study has been made of the effect of repeated annealing on the micro-fracture processes and on the characteristics of low cycle fatigue life of low carbon steel having fine- and coarse-grained microstructures. It was found that repeated annealing has a beneficial effect of suppressing the progress of the fatigue damage inside the material for coarse-grained steel in the extremely low cycle regime. In this case, a remarkable extension of fatigue life is observed with a change of internal to surface fracture mode. Extended fatigue lives are located on the fatigue life curve which was obtained by the extrapolation of the fatigue life curve for a surface fracture mode at low plastic strain range. This finding can be explained using the concept of “the competition of two failure limit lines.”

To achieve a fine periodic semiconductor structure by electron beam (EB) lithography, calixarene was used as an EB resist. A 25 nm pitch InP pattern was formed successfully and 40 nm pitch InP structures were achieved with good reproducibility. A shorter developing time, precise stage motion, accurate control of the widths of lines and spaces, and slight O2 ashing were important to obtain a fine InP pattern by a two-step wet chemical etching process. Furthermore, the fabricated periodic InP pattern was buried in a GaInAs structure by organometallic vapor phase epitaxy. The introduction of tertiarybutylphosphine as the phosphorus source prevented the fine structure from deforming when the temperature was raised and a 25 nm pitch periodic structure was buried successfully.