Low Frequency Ultrasonic Array Imaging using Signal Post-processing for Concrete Material

The use of ultrasonic arrays for conducting non-destructive evaluation has been drastically increased in recent years. As one of the array imaging, a post-processing beam-forming technique has been proposed that utilizes a complete set of signals of all combinations of transmission and reception elements. This approach is referred to as full matrix capture (FMC) [1]. In FMC, each array element is sequentially used as an emitter and all other array elements are used as receivers. By changing the emitting element, we obtained a set of flaw signals that was used to form the focal beam. The delay-and-sum beam reconstruction based on the post-processing was applied to imaging of internal voids and reinforced steel bars in concrete material. The reconstruction of voids and steels in concrete specimen (400mm x 400mm x 400 mm) was demonstrated using a phased array transducer in the low frequency range. In this study, the array transducer with total 16 elements and center frequency of 50 kHz was developed. The volume fraction of aggregates in concrete was 70 %, and the maximum size of the coarse aggregate was 20 mm. Figure 1 shows the reconstruction result of a slit. For on-site inspection, we introduced a graphics processing unit (GPU) computation to accelerate the post-processing of beam-forming [2]. The flaw detection time was approximately 0.15 s using Geforce GTX880M (NVIDIA)

Difficulties and Coping Strategies Experienced by Employed People with HIV in Japan: A Qualitative Study Comparing High and Low Sense of Coherence Groups

People with HIV experience anxiety about discrimination in the workplace and disclosing their disease. Effective coping ability toward HIV-related challenges may be associated with a person’s sense of coherence (SOC). This study describes the range of difficulties HIV-positive individuals experience and their coping strategies, especially in the workplace. The experiences of those with high and low SOC are compared. Data were collected in Japan from 2007 to 2009 using a qualitative approach. Semistructured interviews were conducted with 40 participants with HIV with work experience. Interviews focused on individual’s perspectives, including self-perceptions of physical and mental functioning, work conditions, and perceived changes in their circumstances. Participants were divided into high and low SOC groups based on SOC-13 scores. A number of categories and subcategories of experiences were extracted, including “acute feeling of the severe social positioning of HIV,” with some categories specific to those with low SOC. Those with high SOC appeared to have a unique perspective that supported more successful coping, for example, “Awareness of death is linked to valuing living in the present,” “Do not be discouraged by uncertainties and difficulties,” and so on. It suggests that development of coping skills may help people with HIV

External Pancreatic Juice Drainage Through a Percutaneous Endoscopic Drainage Tube for the Patient With a Postoperative Pancreatic Juice Leakage

Percutaneous endoscopic gastrostomy (PEG) has been widely accepted for patients who have no swallowing ability but have an intact gut. Its clinical application is mainly for nutritional support and decompression of the intestine in patients with bowel obstruction. In this paper, we report external pancreatic juice drainage through a percutaneous endoscopic drainage tube in a patient with postoperative pancreatic juice leakage. Soon after this procedure, pancreatic juice leakage subsided. This procedure was minimally invasive for the patient and may be a new application of PEG to maintain the good quality of life (QOL) in a patient with pancreatic juice leakage

Effects of HLA-DRB1 alleles on susceptibility and clinical manifestations in Japanese patients with adult onset Still’s disease

BackgroundHLA-DRB1 alleles are major determinants of genetic predisposition to rheumatic diseases. We assessed whether DRB1 alleles are associated with susceptibility to particular clinical features of adult onset Still’s disease (AOSD) in a Japanese population by determining the DRB1 allele distributions.MethodsDRB1 genotyping of 96 patients with AOSD and 1,026 healthy controls was performed. Genomic DNA samples from the AOSD patients were also genotyped for MEFV exons 1, 2, 3, and 10 by direct sequencing.ResultsIn Japanese patients with AOSD, we observed a predisposing association of DRB1*15:01 (p = 8.60 × 10−6, corrected p (Pc) = 0.0002, odds ratio (OR) = 3.04, 95% confidence interval (95% CI) = 1.91–4.84) and DR5 serological group (p = 0.0006, OR = 2.39, 95% CI = 1.49–3.83) and a protective association of DRB1*09:01 (p = 0.0004, Pc = 0.0110, OR = 0.34, 95% CI = 0.18–0.66) with AOSD, and amino acid residues 86 and 98 of the DRβ chain were protectively associated with AOSD. MEFV variants were identified in 49 patients with AOSD (56.3%). The predisposing effect of DR5 was confirmed only in patients with AOSD who had MEFV variants and not in those without MEFV variants. Additionally, DR5 in patients with AOSD are associated with macrophage activation syndrome (MAS) and steroid pulse therapy.ConclusionThe DRB1*15:01 and DR5 are both associated with AOSD susceptibility in Japanese subjects. A protective association between the DRB1*09:01 allele and AOSD was also observed in these patients. Our data also highlight the effects of DRB1 alleles in susceptibility to AOSD

Real-time 3D Photoacoustic Visualization System with a Wide Field of View for Imaging Human Limbs [version 2; referees: 2 approved]

Background: A breast-specific photoacoustic imaging (PAI) system prototype equipped with a hemispherical detector array (HDA) has been reported as a promising system configuration for providing high morphological reproducibility for vascular structures in living bodies. Methods: To image the vasculature of human limbs, a newly designed PAI system prototype (PAI-05) with an HDA with a higher density sensor arrangement was developed. The basic device configuration mimicked that of a previously reported breast-specific PAI system. A new imaging table and a holding tray for imaging a subject's limb were adopted. Results: The device’s performance was verified using a phantom. Contrast of 8.5 was obtained at a depth of 2 cm, and the viewing angle reached up to 70 degrees, showing sufficient performance for limb imaging. An arbitrary wavelength was set, and a reasonable PA signal intensity dependent on the wavelength was obtained. To prove the concept of imaging human limbs, various parts of the subject were scanned. High-quality still images of a living human with a wider size than that previously reported were obtained by scanning within the horizontal plane and averaging the images. The maximum field of view (FOV) was 270 mm × 180 mm. Even in movie mode, one-shot 3D volumetric data were obtained in an FOV range of 20 mm in diameter, which is larger than values in previous reports. By continuously acquiring these images, we were able to produce motion pictures. Conclusion: We developed a PAI prototype system equipped with an HDA suitable for imaging limbs. As a result, the subject could be scanned over a wide range while in a more comfortable position, and high-quality still images and motion pictures could be obtained

Applicability of Preoperative Nuclear Morphometry to Evaluating Risk for Cervical Lymph Node Metastasis in Oral Squamous Cell Carcinoma

Background: We previously reported the utility of preoperative nuclear morphometry for evaluating risk for cervical lymph node metastases in tongue squamous cell carcinoma. The risk for lymph node metastasis in oral squamous cell carcinoma, however, is known to differ depending on the anatomical site of the primary tumor, such as the tongue, gingiva, mouth floor, and buccal mucosa. In this study, we evaluated the applicability of this morphometric technique to evaluating the risk for cervical lymph node metastasis in oral squamous cell carcinoma. Methods: A digital image system was used to measure the mean nuclear area, mean nuclear perimeter, nuclear circular rate, ratio of nuclear length to width (aspect ratio), and nuclear area coefficient of variation (NACV). Relationships between these parameters and nodal status were evaluated by t-test and logistic regression analysis. Results: Eighty-eight cases of squamous cell carcinoma (52 of the tongue, 25 of the gingiva, 4 of the buccal mucosa, and 7 of the mouth floor) were included: 46 with positive node classification and 42 with negative node classification. Nuclear area and perimeter were significantly larger in node-positive cases than in nodenegative cases; however, there were no significant differences in circular rate, aspect ratio, or NACV. We derived two risk models based on the results of multivariate analysis: Model 1, which identified age and mean nuclear area and Model 2, which identified age and mean nuclear perimeter. It should be noted that primary tumor site was not associated the pN-positive status. There were no significant differences in pathological nodal status by aspect ratio, NACV, or primary tumor site. Conclusion: Our method of preoperative nuclear morphometry may contribute valuable information to evaluations of the risk for lymph node metastasis in oral squamous cell carcinoma

The development of an acoustic probe to measure the thickness of ferro-manganese crusts

This paper describes the development of an acoustic probe designed to perform in-situ measurements of ferro-manganese crust thickness at depths of up to 3000m. It is planned that this device will operate at low altitudes off the seafloor, mounted onboard an underwater vehicle, and continuously map the crust thickness of regions extending over several kilometres. A prototype probe has been developed together with an algorithm that automatically detects the reflections from the top and bottom surfaces of a layer of crust and measures its thickness. The performance of the system is demonstrated through a series of laboratory experiments carried out using crust samples obtained during the NT09-02 Leg2 of the R/V Natsushima. First, the ability of the system to measure crust thickness at various ranges to the target is assessed. Next, the effects of pressure are investigated in an experiment where the thicknesses of several crust samples are measured at pressures between 0.1 and 30MPa. Finally, the sub-bottom profiles of a number of crust samples, with and without substrates attached are measured.</p

Low Frequency Ultrasonic Array Imaging using Signal Post-processing for Concrete Material

The use of ultrasonic arrays for conducting non-destructive evaluation has been drastically increased in recent years. As one of the array imaging, a post-processing beam-forming technique has been proposed that utilizes a complete set of signals of all combinations of transmission and reception elements. This approach is referred to as full matrix capture (FMC) [1]. In FMC, each array element is sequentially used as an emitter and all other array elements are used as receivers. By changing the emitting element, we obtained a set of flaw signals that was used to form the focal beam. The delay-and-sum beam reconstruction based on the post-processing was applied to imaging of internal voids and reinforced steel bars in concrete material. The reconstruction of voids and steels in concrete specimen (400mm x 400mm x 400 mm) was demonstrated using a phased array transducer in the low frequency range. In this study, the array transducer with total 16 elements and center frequency of 50 kHz was developed. The volume fraction of aggregates in concrete was 70 %, and the maximum size of the coarse aggregate was 20 mm. Figure 1 shows the reconstruction result of a slit. For on-site inspection, we introduced a graphics processing unit (GPU) computation to accelerate the post-processing of beam-forming [2]. The flaw detection time was approximately 0.15 s using Geforce GTX880M (NVIDIA).</p