ALMA ACA detection of submillimeter emission associated with the west hot spot of the radio galaxy Pictor A

In order to investigate the far-infrared excess detected from the west hot spot of the radio galaxy Pictor A with the Herschel observatory, a submillimeter photometry is performed with the Atacama Compact Array (ACA) of the Atacama Large Millimeter/submillimeter Array at Band 8 with the reference frequency of 405 GHz. A submillimeter source is discovered at the radio peak of the hot spot. Because the 405 GHz flux density of the source, $80.7\pm3.1$ mJy, agrees with the extrapolation of the synchrotron radio spectrum, the far-infrared excess is suggested to exhibit no major contribution at the ACA band. In contrast, by subtracting the power-law spectrum tightly constrained by the radio and ACA data, the significance of the excess in the Herschel band is well confirmed. No diffuse submillimeter emission is detected within the ACA field of view, and thus, the excess is ascribed to the west hot spot itself. In comparison to the previous estimate based on the Herschel data, the relative contribution of the far-infrared excess is reduced by a factor of $\sim 1.5$. The spectrum of the excess below the far-infrared band is determined to be harder than that of the diffusive shock acceleration. This strengthens the previous interpretation that the excess originates via the magnetic turbulence in the substructures within the hot spot. The ACA data are utilized to evaluate the magnetic field strength of the excess and of diffuse radio structure associated to the hot spot.Comment: 10 pages,4 figures, 3 tables, accepted for Ap

The Construction Of A Business Model For Intellectually Disabled Workers

The Japanese welfare system has undergone rapid change. A law has been enacted that requires the handicapped to work in order to be independent from government assistance. However, it is difficult for the intellectually disabled (ID) to earn a living wage because of a lack of understanding with respect to their ability and communication skills. Our organization conducts business with ID individuals such as those with autism. The business model for the income of our organization and the ID individuals concerned was successfully constructed through an understanding and application of the characteristics of ID individuals. This paper shows the current environment affecting the ID and presents our strategic and successful business model that is designed to enable them to achieve a realistic livelihood

Practical Approaches to Four-dimensional Heavy-Charged-Particle Lung Therapy

We have developed new design algorithms for compensating boli to facilitate the implementation of four-dimensional charged-particle lung therapy in clinical applications. Four-dimensional CT (4DCT) data for eight lung cancer patients were acquired with a 16-slice CT under free breathing. Six compensating boli were developed that may be categorized into three classes, i) boli-based on contoured gross tumor volumes (GTV) from a 4DCT data set during each respiratory phase, subsequently combined into one (GTV-4DCT bolus); ii) boli-based on contoured internal target volume (ITV) from image-processed 3DCT data only [temporal-maximum-intensity-projection (TMIP)/ temporal-average-intensity-projection (TAIP)] with calculated boli (ITV-TMIP and ITV-TAIP boli); and iii) boli-based on contoured ITV utilizing image-processed 3DCT data, applied to 4DCT for design of boli for each phase, which were then combined. The carbon beam dose distribution within each bolus was calculated as a function of time and compared to plans in which respiratory-ungated/gated strategies were used. The GTV-4DCT treatment plan required a prohibitively long time for contouring the GTV manually for each respiratory phase, but it delivered more than 95% of the prescribed dose to the target volume. The TMIP and TAIP treatments, although more time-efficient, resulted in an unacceptable excess dose to normal tissues and underdosing of the target volume. The dose distribution for the ITV-4DCT bolus was similar to that for the GTV-4DCT bolus and required significantly less practitioner time. The ITV-4DCT bolus treatment plan is time-efficient and provides a high-quality dose distribution, making it a practical alternative to the GTV-4DCT bolus treatment plan

Dosimetric Variation Due to CT Inter-Slice Spacing in Four-Dimensional Carbon Beam Lung Therapy

Purpose: When CT data with a thick slice thickness are used in treatment planning, geometrical uncertainty may induce dosimetric errors. We evaluated carbon ion dose variations due to different CT slice thicknesses using a four-dimensional (4D) carbon ion beam dose calculation, and compared results between ungated and gated respiratory strategies.Material and Methods: Seven lung patients were scanned in 4D mode with a 0.5-mm slice thickness using a 256-multi-slice CT scanner. CT images were averaged with various numbers of images to simulate reconstructed images with various slice thicknesses (0.5 mm-5.0 mm). Two scenarios were studied (respiratory-ungated and -gated strategies). Range compensators were designed for each of the CT volumes with coarse inter-slice spacing to cover the internal target volume (ITV), as defined from 4DCT. Carbon ion dose distribution was computed for each resulting ITV on the 0.5-mm slice 4DCT data. The accumulated dose distribution was then calculated using deformable registration for 4D dose assessment.Results: The magnitude of over- and under-dosage was found to be larger with the use of range compensators designed with a coarser inter-slice spacing than those obtained with a 0.5-mm slice thickness. Although no under dosage was observed within the clinical target volume (CTV) region, D95 remained at over 97% of the prescribed dose for the ungated strategy and 95% for the gated strategy for all slice thickness. Inter-slice spacing of less than 3 mm may be able minimize dose variation between the ungated and gated strategies.Conclusions: Although volumes with increased inter-slice spacing may reduce geometrical accuracy at a certain respiratory phase, this does not significantly affect delivery of the accumulated dose to the target during the treatment course

Design of a Compensating Bolus by Use of Exhalation CT Data for Covering Residual Motion in Respiratory-Gated Charged-Particle Lung Therapy: Four-Dimensional Carbon Beam Dose Calculation

We developed an algorithm which we used to design a compensating bolus by using respiratory-gated CT data for respiratory-gated carbon beam lung therapy and evaluated it by calculating dose distributions as a function of time. Four-dimensional CT (4DCT) images were obtained for seven lung cancer patients under free breathing conditions. The internal target volume (ITV) was calculated by maximum intensity projection processing which use of three types of gross tumor volumes (GTVs): at peak exhalation and with a 5 mm shift of the GTV to both superior and inferior sides. Then a compensating bolus was designed which use of the ITV and applied to 4DCT data at the gating window (around exhalation phase). The carbon beam distribution was calculated by a pencil-beam algorithm as a function of time. The compensating bolus provides a sufficient prescribed dose to the target in the gating window and minimizes any excessive dose to the normal tissues. The metric of dosimetric assessment metrics of D95 in all patients is greater than 96% of the prescribed dose in the gating window. Our results will be beneficial for improving the accuracy of charged-particle radiotherapy for hospitals where 4DCT cannot be used

Intrafractional Respiratory Motion for Charged Particle Lung Therapy with Immobilization Assessed by Four-Dimensional Computed Tomography

The aim of this study was to quantify the magnitude of intrafractional lung tumor motion under free-breathing conditions with an immobilization device using four-dimensional computed tomography (4DCT). 4DCT data sets were acquired for 17 patients with lung tumors receiving carbon ion beam therapy. A single respiratory cycle was subdivided into 10 phases, and intrafractional tumor motion was calculated by identifying the gross tumor volume (GTV) center of mass (COM) in two scenarios; respiratory-ungated and -gated treatments, which were based on a whole respiratory cycle and a 30% duty cycle around peak exhalation, respectively. For the respiratory-ungated case, the mean (± standard deviation) GTV-COM dis-placements from the peak exhalation position over the 17 patients were 0.6 (± 0.8) / 0.9 (± 1.2) mm, 2.0 (± 1.4) / 0.4 (± 0.7) mm, and 0.2 (± 0.5) / 7.8 (± 6.9) mm in left/right, anterior/posterior and superior/infe-rior directions, respectively, while these were reduced for the respiratory-gated case to 0.3 (± 0.4) / 0.4 (±0.6) mm (left/right), 0.8 (± 0.7) / 0.3 (± 0.5) mm (anterior/posterior), and 0.1 (± 0.2) / 2.8 (± 2.9) mm (superior/inferior). Quantitative analysis of tumor motion with immobilization is valuable not only for par-ticle beam therapy but also for photon beam therapy