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The Telescope Array (TA) is an international experiment studying ultra-high energy cosmic rays. TA uses the fluorescence detection technique to observe cosmic rays. In order to estimate the energy of cosmic rays with a fluorescence detector (FD), it is necessary to measure the condition of the observation area. Clouds affect the accuracy of the energy estimation. It is necessary to measure the existence of clouds and their direction in the Field Of View (FOV) of the FD. We developed a cloud monitoring system to measure the night sky weather using a CCD camera. In this report, we present our progress on our CCD cloud monitoring system.

In the future, ultra-high energy cosmic ray (UHECR) observatory will be expanded due to the small flux. Then, cost reduction is useful strategy to realize a huge scale observatory. For this purpose, we are developing a simple structure cosmic ray detector named as Cosmic Ray Air Fluorescence Fresnel-lens Telescope (CRAFFT). We deployed CRAFFT detectors at the Telescope Array site and performed a test observation. We have successfully observed UHECR air showers. We will report the status and the result of the test observation.

We developed a compact but versatile laser-induced fluorescence spectrum (LIFS) lidar that has potential use for material or aerosol identification outside experimental rooms. The compactness and mobility of the LIFS lidar means observations can be more freely conducted at any place and any time. Its performance characteristics were validated by threedimensional fluorescence imaging of targets and remote detection of quasi bio/organic aerosols.

• We devised a new dose metric (f(0)CB w) for cone-beam CT dosimetry. • The f(0)CB w method adopted new measurement positions of a cylindrical phantom. • The f(0)CB w method can estimate the average phantom dose within 4.1% error. • The f(0)CB w method is more suitable than the conventional CTDI w method. • The results of this study would be useful for the future of CBCT dosimetry. The conventional weighted computed tomography dose index (CTDI w) may not be suitable for cone-beam computed tomography (CBCT) dosimetry because a cross-sectional dose distribution is angularly inhomogeneous owing to partial angle irradiations. This study was conducted to develop a new dose metric (f(0)CB w) for CBCT dosimetry to determine a more accurate average dose in the central cross-sectional plane of a cylindrical phantom using Monte Carlo simulations. First, cross-sectional dose distributions of cylindrical polymethyl methacrylate phantoms over a wide range of phantom diameters (8–40 cm) were calculated for various CBCT scan protocols. Then, by obtaining linear least-squares fits of the full datasets of the cross-sectional dose distributions, the optimal radial positions, which represented measurement positions for the average phantom dose, were determined. Finally, the f(0)CB w method was developed by averaging point doses at the optimal radial positions of the phantoms. To demonstrate its validity, the relative differences between the average doses and each dose index value were estimated for the devised f(0)CB w , conventional CTDI w , and Haba's CTDI w methods, respectively. The relative differences between the average doses and each dose index value were within 4.1%, 16.7%, and 11.9% for the devised, conventional CTDI w , and Haba's CTDI w methods, respectively. The devised f(0)CB w value was calculated by averaging four "point doses" at 90° intervals and the optimal radial positions of the cylindrical phantom. The devised method can estimate the average dose more accurately than the previously developed CTDI w methods for CBCT dosimetry. [ABSTRACT FROM AUTHOR]

Purpose: The beam model in radiation treatment planning systems (RTPSs) plays a crucial role in determining the accuracy of calculated dose distributions. The purpose of this study was to ascertain differences in beam models and their dosimetric influences when a golden beam dataset (GBD) and multi‐institution measured beam datasets (MBDs) are used for beam modeling in RTPSs. Methods: The MBDs collected from 15 institutions, and the MBDs' beam models, were compared with a GBD, and the GBD's beam model, for Varian TrueBeam linear accelerator. The calculated dose distributions of the MBDs' beam models were compared with those of the GBD's beam model for simple geometries in a water phantom. Calculated dose distributions were similarly evaluated in volumetric modulated arc therapy (VMAT) plans for TG‐119 C‐shape and TG‐244 head and neck, at several dose constraints of the planning target volumes (PTVs), and organs at risk. Results: The agreements of the MBDs with the GBD were almost all within ±1%. The calculated dose distributions for simple geometries in a water phantom also closely corresponded between the beam models of GBD and MBDs. Nevertheless, there were considerable differences between the beam models. The maximum differences between the mean energy of the energy spectra of GBD and MBDs were −0.12 MeV (−10.5%) in AcurosXB (AXB, Eclipse) and 0.11 MeV (7.7%) in collapsed cone convolution (CCC, RayStation). The differences in the VMAT calculated dose distributions varied for each dose region, plan, X‐ray energy, and dose calculation algorithm. The ranges of the differences in the dose constraints were −5.6% to 3.0% for AXB and −24.1% to 2.8% for CCC. In several VMAT plans, the calculated dose distributions of GBD's beam model tended to be lower in high‐dose regions and higher in low‐dose regions than those of the MBDs' beam models. Conclusions: We found that small differences in beam data have large impacts on the beam models, and on calculated dose distributions in clinical VMAT plan, even if beam data correspond within ±1%. GBD's beam model was not a representative beam model. The beam models of GBD and MBDs and their calculated dose distributions under clinical conditions were significantly different. These differences are most likely due to the extensive variation in the beam models, reflecting the characteristics of beam data. The energy spectrum and radial energy in the beam model varied in a wide range, even if the differences in the beam data were <±1%. To minimize the uncertainty of the calculated dose distributions in clinical plans, it was best to use the institutional MBD for beam modeling, or the beam model that ensures the accuracy of calculated dose distributions. [ABSTRACT FROM AUTHOR]

We make a 2-D transient analysis of field-plate AlGaN/GaN HEMTs with a semi-insulating buffer layer, where only a deep acceptor above the midgap is considered. The deep-acceptor density is varied between 1017 cm−3and 8 \times 10^17 cm−3. It is studied how the deep-acceptor density and the field plate affect the buffer-related drain lag and gate lag, and current collapse. It is shown that the lags and current collapse are reduced by introducing a field plate. This reduction occurs because electron trapping by the deep acceptors is weakened by the field plate. It is also shown that without a field plate, the drain lag and current collapse increase with increasing the deep-acceptor density as expected, although the gate lag decreases when the deep-acceptor density becomes high in the region between 2\times 10^17 cm−3and 8 \times 10^17 cm−3. On the other hand, with a field plate, surprisingly, the lags and current collapse decrease when the deep-acceptor density becomes high. This is attributed to the fact that the reduction in drain lag and current collapse by introducing a field plate becomes more significant when the deep-acceptor density becomes higher. [ABSTRACT FROM PUBLISHER]

Background: Radiation pneumonitis (RP) and organizing pneumonia (OP) are the two main types of lung damage that can occur after lung irradiation. The goal of this study was to evaluate the relationship between RP and OP after irradiation for breast cancer. Methods: Four hundred and twenty-eight patients who underwent radiotherapy for breast cancer were identified. The whole breast was irradiated with two tangential photon beams. Chest computed tomography (CT) scan were performed when patients showed any symptoms that were suspicious for pneumonitis. Results: Five patients (1.2%) were diagnosed with OP. All five patients showed ground glass opacities and consolidation of the border of the lesion of RP in the radiation fields. Infiltration of OP spread from the site of RP to the hilum of the ipsilateral lung. Between RP and OP, a free region space (FRS) could be detected. Conclusions: OP is closely related to RP. All OP lesions developed near the site of RP. [ABSTRACT FROM AUTHOR]

Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ecological advantage from reduced genetic diversity because of the associated reduction in inter-colony conflict. Here we report population genetic analyses, along with colony fusion experiments, for a highly invasive colonial ascidian, Didemnum vexillum. Analyses based on mitochondrial cytochrome oxidase I (COI) partial coding sequences revealed two distinct D. vexillum clades. One COI clade appears to be restricted to the probable native region (i.e., north-west Pacific Ocean), while the other clade is present in widely dispersed temperate coastal waters around the world. This clade structure was supported by 18S ribosomal DNA (rDNA) sequence data, which revealed a one base-pair difference between the two clades. Recently established populations of D. vexillum in New Zealand displayed greatly reduced COI genetic diversity when compared with D. vexillum in Japan. In association with this reduction in genetic diversity was a significantly higher inter-colony fusion rate between randomly paired New Zealand D. vexillum colonies (80%, standard deviation ±18%) when compared with colonies found in Japan (27%, standard deviation ±15%). The results of this study add to growing evidence that for colonial organisms reductions in population level genetic diversity may alter colony interaction dynamics and enhance the invasive potential of newly colonizing species. [ABSTRACT FROM AUTHOR]

To examine the evolutionary origin of the chordate nervous system, an outgroup comparison with hemichordates is needed. When the nervous systems of chordates and hemichordates are compared, two possibilities have been proposed, one of which is that the chordate nervous system has evolved from the nervous system of hemichordate-like larva and the other that it is comparable to the adult nervous system of hemichordates. To address this issue, we investigated the entire developmental process of the nervous system in the acorn worm Balanoglossus simodensis. In tornaria larvae, the nervous system developed along the longitudinal ciliary band and the telotroch, but no neurons were observed in the ventral band or the perianal ciliary ring throughout the developmental stages. The adult nervous system began to develop at the dorsal midline at the Krohn stage, considerably earlier than metamorphosis. During metamorphosis, the larval nervous system was not incorporated into the adult nervous system. These observations strongly suggest that the hemichordate larval nervous system contributes little to the newly formed adult nervous system. [ABSTRACT FROM AUTHOR]

The Hox genes and its evolutionary sister, the ParaHox genes, are widely distributed among animals. Although it has been expected that hemichordates and echinoderms have a single set of Hox genes and most likely a single set of ParaHox genes, it is not known whether the ortholog of Hox8 is absent in hemichordates, and in turn, consensus view about Hox/ParaHox gene complements in hemichordates has not been established. In this study, we isolated either complete or nearly complete coding sequences of 12 Hox genes, including the ortholog of the Hox8 that has not been reported in the previous studies, and three ParaHox genes from the recently discovered indirect-developing acorn worm, Balanoglossus simodensis. Our data suggest that the ancestral hemichordate had intact complements of ambulacrarian prototypical Hox and ParaHox genes, consisting of 12 and three members, respectively. [ABSTRACT FROM AUTHOR]

The article discusses the effects of electronic information and Internet on library and a user. It focuses on the impacts of Web 2.0 on library services and user access to information. It also examines the reference service of libraries and its functions on the users. In addition, it explains the levels of mediation of C. C. Kuhlthau. According to the author, the promotion and use of electronic information changes the way users learn and solve their problems. Moreover, digital environment uplifts the expectation of users to learn more fastly.

Two target sites in Japan Sea, Toyama Bay and Shiribeshi Seamount, were studied using deep-sea submersibles to 'dowse' or imply seafloor methane seepage by analysis of ester-linked phospholipid fatty acids in sediments. No methane seeps in the studied sites had been reported before. The sediments associated with yellow to red patches showed a relatively high abundance of phospholipid fatty acids with biomarkers for sulfate-reducing bacteria and methane-oxidizing bacteria. Similar phospholipid fatty acid compositions were found in the sediments near the dense colonies of the deep-sea tunicate Megalodicopia hians . The tunicate colonies were first discovered in the coastal Japan area by this study, and their association with possible methane seepage was suspected. These results suggest that microflora with sulfate-reducing and methane-oxidizing bacteria may have developed in adaptation to methane seepage in the bathyal Japan Sea floor, where gas hydrate is likely formed beneath. In addition, supplement 16S rDNA data from the yellow patch sediment in Toyama Bay suggested that sulfur-oxidizing bacteria occur in response to sulfide supplied by sulfate-reducing bacteria. As methane is a more effective greenhouse gas than carbon dioxide and thus has more impact on global biosphere from aquatic systems, these observations call for the survey of the distribution of methane seeps associated with faults and subsurface gas hydrate in the coastal Japan Sea. [ABSTRACT FROM AUTHOR]

Ascidians inhabit both shallow water and the deep sea. The phylogenetic position of deep-sea ascidians has not been sufficiently investigated because of their unusual habitats. The family Octac-nemidae is one such enigmatic deep-sea ascidian. In this report, we determined the sequences of the 18SrDNA and a mitochondrial protein gene of Megalodicopia hians belonging to the family Octacnemidae and we analyzed its phylogenetic relationship with other ascidians. A phylogenetic relationship of this family with the families Cionidae and/or Corellidae has been suspected based on a small number of morpho-logical characteristics. However, our results suggested that M. hians has a close relationship to the family Corellidae and might originate from them. This is the first report of the molecular phylogenetic analysis of a deep-sea ascidian. [ABSTRACT FROM AUTHOR]

The morphology and life history of a strange and unidentified botryllid ascidian were investigated. This ascidian was first collected from the stony shore of Ebisu Island in Shimoda. a city on Izu peninsula in central Japan. Unlike other botryllid ascidians. whose colonies are flat and smooth, this ascidian's colonies are rugged. In each colony, zooids are arranged into several oval systems, each of which has a thick part containing zooids and very thin parts that do not. The arrangement of ovary and testis in this species is the same as in other species of the genus Botryllus; the ovary is situated anterior to the testis, The embryo of this ascidian develops in the peribranchial cavity of its mother zooid without any brooding organs, as is the case with Botryllus scalaris and Botryllus puniceus. Meanwhile, the results of cut colony assay experiments did not show the existence of colony specificity in this ascidian, Even when two syngeneic colonies were brought into contact a! their growing edges, none fused together. On the other hand, when two colonies were brought into contact with each other at their cut surfaces, they always fused into a single colony, regardless of their origin. Therefore, this species may be the only species that lacks colony specificity among the botryllids studied so far. [ABSTRACT FROM AUTHOR]

The morphology and life history of a new species of the genus Botryllus belonging to the family Botryllidae are described in detail This ascidian was collected from the stony shore in the cove near Shimoda Marine Research Center, University of Tsukuba (Shimoda, Shizuoka Prefecture, Japan). The ascidian colony was easily distinguished from colonies of other botryllids because it was very thin and bright pink in color. The arrangement of ovary and testis in this ascidian was the same as that in other species of the genus Botryllus. This ascidian was prolific, with 1-5 embryos on each side of a zooid. and the embryos of this ascidian developed in the peribranchial cavity without any brooding organs as in Botryllus scalaris. We observed the processes and features of the allorecognition reaction in colony specificity and found that allorejection occurred after fusion of the vascular system between two incompatible colonies. This manner of allorejection is also shown in B. scalaris and Botryllus delicatus; however, the reaction speed of allorejection is faster than that of B. delicatus and similar to that of B. scalaris. These results indicate that this ascidian might be closely related to B. scalaris. [ABSTRACT FROM AUTHOR]

Xenogeneic rejection was observed among colonies of three botryllids, Botryllus scalaris, Botryllus primigenus, and Botrylloides simodensis. Allogeneic recognition occurs in each of these species, but the manner of allogeneic rejection differs among them. We studied xenogeneic rejection reactions among these species under the following conditions: colony contact at natural growing edges, colony contact at artificially cut surfaces, and injection of xenogeneic blood plasma into a vascular vessel. In the first two cases, xenogeneic rejection occurred only in Botryllus primigenus and Botrylloides simodensis. The features of that xenogeneic rejection were similar to those of allogeneic rejection in each of these two botryllids. Injection of xenogeneic blood plasma induced responses similar to those of allogeneic rejection in all three botryllids. It is interesting to note that colonies of Botryllus scalaris never showed any response against injected blood plasma from allogeneic incompatible colonies, unlike the responses seen in colonies of the other two botryllids under the same conditions. On the basis of these results, the relationship between allogeneic and xenogeneic rejection in botryllids is discussed. [ABSTRACT FROM AUTHOR]

Ultrastructures of circulating hemocytes were studied in 9 botryllid ascidians. The hemocytes are classified into five types: hemoblasts, phagocytes, granulocytes, morula cells, and pigment cells. These five types are always found in the 9 species. They should represent the major hemocyte types of the circulating cells in the blood. Hemoblasts are small hemocytes having a high nucleus/cytoplasm ratio, There are few granular or vacuolar inclusions in the cytoplasm. Phagocytes have phagocytic activity and their shape is variable depending on the amount of engulfed materials. In granulocytes, shape and size of granules are different among the species. Morula cells are characterized by several vacuoles filled with electron dense materials. In pigment cells, the bulk of the cytoplasm is occupied by one or a few vacuoles containing pigment granules. We also described some other hemocyte types found in particular species. Furthermore, we encountered free oocytes circulating in the blood in two species, Botryllus primigenus and Botrylloides lentus. [ABSTRACT FROM AUTHOR]

Focuses on a study which described the morphology and life history of an ascidian found at Noroshi Point in Shimoda, Japan. Observations on morphology; Colony specificity.

Focuses on a study which examined the xenogeneic rejection reactions among four compound ascidians of the genus Botrylloides to compare with the allogeneic rejections of these species. Xenogeneic reactions induced by growing edge contact; Xenogeneic reactions induced by cut surface contact; Phenoloxidase activity of hemocytes.

Presents information on a study which observed the formative processes of the brooding organs of the botryllid ascidians, Botryllus delicatus and Botryllus sexiens. Materials and methods; Results; Discussion.

Presents information on a study which investigated the morphology and life history of an unidentified botryllid ascidian that was first collected from the stony shore of Shikine Island of the Izu Islands in Japan. Materials; Methodology; Results and discussion.

The colony specificity of colonial animais involves alIorejection reactions, which are the defense reactions for allogeneic tissues that occur naturally. In colonial botryllid ascidians, all of the species already studied have colony specificity, and their allorejection modes differ from one another. However, in most of these botryllids, morula cells (MCs) always participate in the allorejection reactions, and the prophenoloxidase (proPO) system of MCs is considered to contribute to the allorejection reaction. The present study was performed using five botryllids and Symplegma reptans, which is closely related to botryllids, in an effort to clarify the relationship between the modes of allorejection and the characteristics of MCs, such as the ratio of MCs to total hemocytes and the phenoloxidase (PO) activity levels in the MCs. The MCs of these six ascidians resembled one another morphologically and the MCs of all species showed PO activity. In Botryllus scalaris, PO activity was also found in granular leukocytes, but the level of activity was much Iower than that in MCs. The PO of these species resembles one another, at least in terms of their sensitivity to inhibition by common inhibitors of the proPO system. The PO activity per fixed number of hemocytes varied among these ascidians. This variation was due to a difference in the ratio of MCs to total hemocytes and/or a difference in PO activity per MC. In most ascidians, except for B. scalaris, the rejection reaction area showed a higher level of PO activity than the fusion area of the syngeneic colonies. These results suggest that the characteristics of MCs including their PO activity are closely correlated with the mode of the allorejection reaction. [ABSTRACT FROM AUTHOR]