On SNS (Social Networking Services), detecting Sybils is an urgent demand. The most famous approach is called “SybilRank” scheme where each node evenly distributes its trust value starting from honest seeds and detects Sybils based on the trust value. Furthermore, Zhang et al. propose to avoid trust values from being distributed into Sybils by pruning suspicious relationships before performing SybilRank. However, we point out that the above two schemes have shortcomings that must be remedied. In the former scheme, seeds are concentrated on the specific communities because they are selected from nodes that have largest number of friends, and thus the trust value is not evenly distributed. In the latter one, a sophisticated attacker can avoid graph pruning by making relationships between Sybil nodes. In this paper, we propose a robust seed selection and graph pruning scheme to detect Sybil nodes more accurately. To more evenly distribute trust value into honest nodes, we first detect communities in the SNS and select honest seeds from each detected community. And then, by leveraging the fact that Sybils cannot make dense relationships with honest nodes, we also propose a graph pruning scheme based on the density of relationships between trusted nodes. We prune the relationships which have sparse relationships with trusted nodes and this enables robust pruning malicious relationships even if the attackers make a large number of common friends. By the computer simulation with real dataset, we show that our scheme improves the detection accuracy of both Sybil and honest nodes.

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9日令のヒナ280羽を無感染対照, Eimeria tenella 胞子形成オーシスト1万個感染(Et-5), 5万個感染(Et-5), および E. acervulina 50万個感染(Ea)の4群に分けた. 感染後の経過に伴い各群5～8羽ずつ抽出して剖検し, 体重, 臓器重量, 血液所見, 消化管病変を測定ならびに観察した. Et の各群では, 感染4日後に血便の排泄が始まり, それにひきつづき種々の症状が現われた. おもな所見は死亡(Et-5), 摂食量の減退, 体重減少, 脾臓と肝臓の肥大, 盲腸の萎縮病変, 赤血球数・血色素濃度・ヘマトクリット値および血漿総蛋白濃度の低下であった. これらの症状の多くは, 感染10～l5日後までに回復したが, 盲腸病変は30日後でも回復しなかった. しかし, 耐過生存したものの成長は, 無感染対照群とほとんど変わらないほどに回復した. Ea 群では, 感染3日後より顕著な症状が現われ, とくに摂食量の減退, 成長抑制, 心臓の縮少が著しく, 粘着性に富む糞便を排泄した. 血液では赤血球の変化は小さかったが, 血漿蛋白濃度は著しく低下した. これらの症状の多くは, 感染10日後までには回復し, これはオーシストの排泄が終わるのに一致した. 血液成分にみられた変化は Et 群に比べて小さかったが, 期間がやや長かった. Ea の群で最も注目すべき所見は, 発病期にみられた成長抑制が慢性的経過をたどり, 感染30日後でも回復しなかったばかりか, 無感染対照群との成長の差がさらに大きくなる傾向を示していることであった.

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The effect of spermidine, a type of polyamine present in exudates from inflamed tissues and bacteria-infected sites in humans, on calcium mobilization of leukotriene B₄ (LTB₄)-stimulated chicken abdominal macrophages and heterophils was examined in vitro. The intracellular calcium ion concentration [Ca²⁺]_i was elevated immediately and reached a maximum a few seconds after the addition of LTB₄. The elevated [Ca²⁺]_i returned to the basal (resting) level approximately 2min after LTB₄ addition. Pretreatment of cells with spermidine significantly prolonged the duration of [Ca²⁺]_i elevation in LTB₄-treated chicken phagocytes. However, no change was induced in the level of [Ca²⁺]_i elevation by pretreating the LTB₄-treated cells with spermidine. These results suggest that polyamines would enhance the activities of chicken macrophages and heterophils in inflammation sites and bacteria-infected sites through delaying the return to resting levels of stimulated cells, as in the case of human polymorphonuclear leukocytes.

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An automatic counting method was developed for fish blood cells using a fluorescent dye, 3, 3-dihexyloxacarbocyanine (DiOC ₆(3)), that selectively stain lipid bilayers in living cells. In the present study, the DiOC₆(3) method was applied to quail (Cotumix cotumix japonica) blood cells. After quail blood cells were stained with DiOC₆(3), absolute counts and relative proportions of erythrocytes, granulocytes, monocytes, and lymphocytes plus thrombocytes in whole blood were obtained by means of flow cytometry (FC). The number of each cell types by the FC was in good agreement with those counted microscopically. This method will offer new possibilities for routine blood cell counting for avian medicine.

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Cytoplasmic calcium ion concentrations [Ca²⁺]_i were measured for the first time in chicken heterophils and macrophages stimulated with Leukotriene B₄ (LTB₄), phorbol myristate acetate (PMA), formyl-methionyl-leucyl-phenylalanine (fMLP) and lipopolysaccharide (LPS) which are known to be activating factors of phagocyte functions. [Ca²⁺]_i in rat neutrophils and macrophages was also measured after stimulation with these activating factors. [Ca²⁺]_i was measured by the Fura-2-AM-loading method using an intracellular ion analyzer. Resting levels of [Ca²⁺]_i in chicken phagocytes were similar to those reported previously in rats. [Ca²⁺]_i of chicken phagocytes was elevated by treatment with LTB₄, PMA and LPS, and the patterns and duration times of the elevation of [Ca²⁺]_i by these factors resembled those in rat phagocytes. However, fMLP did not elevate [Ca²⁺]_i in chicken phagocytes, although the agent elevated [Ca²⁺]_i of rat phagocytes. The degree of elevation of [Ca²⁺]_i in chicken heterophils and macrophages stimulated by LTB₄, PMA and LPS was significantly higher than that in the same kinds of rat phagocytes (neutrophils and macrophages) stimulated with the corresponding factors. The degree of elevation of [Ca²⁺]_i in granulocytes treated with these factors was significantly higher than that in macrophages in chickens and rats. The reasons for these differences are unclear at the present time. It is valuable to examine the reason for these differences.

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This special issue includes works related to the ongoing project “Regional Resilience Enhancement through Establishment of Area-BCM at Industry Complexes in Thailand.” This special issue can be considered evidence that the research and development of this project follows and supports the sustainable development goals (SDGs). Let’s imagine we are taking a tour of Area-Business Continuity Management (Area-BCM) and SDGs together.

As a starter, the baseline concept of our Area-BCM is discussed (Kodaka et al.) followed by the papers focusing on the specific SDGs.

Toward SDG Goal 11 Sustainable Cities and Communities

We can start the tour with this goal, as it is the project’s primary focus. In order to have sustainable cities and communities, the concept of Area-BCM can be considered. Related to it, there is a study that reviews and suggests the critical success factors (Meechang and Watanabe). Moreover, we can see the possibility of extending the concept of business continuity to other service sectors, such as tourism during COVID-19 (Yudha et al.).

Toward SDG Goal 8 Decent Work and Economic Growth

Let’s move to the next goal. There is a study exploring the well-being of working people and its likelihood among the local people in the community (Duangkaew et al.). People can be considered human resources in the Area-BCM. Accordingly, learning how people fared during a disaster allows us to design the suitable Area-BCM strategies for organizations. With sustainable employment aspects, inundation model for industrial park-scale is proposed for decision making regarding business continuity (Kakinuma et al.). And a practical model for shared risk assessment within multi-stakeholder is discussed for decision as a community (Ono).

Toward SDG Goal 13 Climate Action

Regarding the third goal, it is necessary to know the outcome of hazard analysis for us to understand the risks. Thus, an approach to flood hazard mapping using the Rainfall-Runoff-Inundation model is presented (Sriariyawat et al.). Through various techniques, flood inundation models are developed. Furthermore, detailed flood inundation model with different return period is proposed for more flexible and feasible decision making (P. C. et al.).

There is still on a way to go. Nevertheless, we hope that these current findings will guide the future research and development of Area-BCM.

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A 57-year-old man presented with a posterior fossa hemangioblastoma associated with primary hyperparathyroidism. The hemangioblastoma was completely removed. Further imaging found parathyroid and thyroid tumors which were resected. Hyperparathyroidism might be a manifestation of von Hippel-Lindau (VHL) disease, but sequencing of the VHL gene of the constitutional deoxyribonucleic acid of the hemangioblastoma was negative. The present association is rare, but the hemangioblastoma and the parathyroid adenoma may have some germ-line mutation in common.

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This paper aims to present a study of a shrinkage potential of cement and/or fly ash treated soft clay. The soft clay specimens used in this study were prepared from reconstituted Bangkok clay. The soil-cement mix specimens were prepared with cement/clay-water ratio (C/wc) of 0.2, 0.3 and 0.4 and the liquidity index (LI) of 1.0, 1.3 and 1.6. The fly ashes as wastes from the electricity generating industries were used in this study. The replacement ratios of fly ash to cement were varied from 15 to 60% by weight. The experiments were performed to determine the strength, stiffness and shrinkage potential. The strength and stiffness were determined by the unconfined compressive strength (UCS) and the secant Young’s modulus at 50% of strength (E50). The shrinkage potential was loosely defined based on an image processing technique. Finally, the results of the study could be used to draw a conclusion of optimised fly ash and cement contents for the soft soil improvement.

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Effect of heat treatment (solution treatment and aging treatment at 443K) on the tensile strength between room temperature and 773K was investigated of the aluminum-borate whisker reinforced (V_f=0.16 and 0.29) 6061 aluminum alloys. Tensile strength of the as-cast 0.29 V_f composite is in the measured temperature range about twice higher than that of the matrix alloy. No whiskers are observed on the fracture surfaces of the composites up to 573K. Both tensile strengths of the matrix alloy and of the 0.29 V_f composite are increased by aging treatment. The degree of the increase is, however, smaller for the composite than the matrix alloy. In the heat-treated composites, whiskers are observed on the fracture surfaces. This result shows that the strength of matrix alloy/whisker interface is decreased by the heat treatment.

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A compact mouse MRI has been developed using a 1.0T yokeless permanent magnet and portable MRI console. The entire system was installed in a space measuring 2 m×1 m. The imaging region was the cylindrical volume (35 mm diameter, 50 mm length) at the center of the magnet and was used for whole-brain or body imaging of mice. Whole-brain imaging took less than 90 min for T₁- and T₂-weighted 3D images with 2-mm slice thickness and 200-μm in-plane resolution. Body imaging took less than 30 min for T₁-weighted spin-echo and FLASH 3D images with 0.5- to 1.0-mm slice thickness and 250- to 300-μm in-plane resolution. In addition to the compactness of the system, the mouse MRI has several advantages over high-field superconducting animal MRI systems in its accessibility to the specimen, similarity to clinical MRI in image contrast, capacity for biological isolation, and maintenance. The results obtained demonstrate the potential of this new system for routine imaging in biomedical laboratories.

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「かいこう7000 II」は, 深度7000mまで潜航可能なRemotely Operated Vehicle (ROV) である. 「かいこう7000 II」はランチャーとビークルの2つで構成され, 母船とランチャーは1次ケーブル, ランチャーとビークルは2次ケーブルで繋がれている. 従来の構成では, 1次ケーブルにはシングルモード (SM : Single Mode) 光ファイバが採用され, 2次ケーブルにはマルチモード (GI : Graded Index) 光ファイバが採用されていた. このGIの伝送量は, ハイビジョン映像等の大容量データを伝送するには不十分で, 大容量通信に適したSMへの換装が求められていた. そこで, 海洋研究開発機構では2009年よりSMを採用した2次ケーブルへの換装を進め, 2011年2月の海域試験での通信試験において「かいこう7000 II」の光伝送経路のSM化を達成した. SM化により, 伝送容量が飛躍的に向上し, ハイビジョン映像等の大容量の通信が可能となった. 本報告では, 「かいこう7000 II」の光伝送経路の概要と, 2011年2月に行われた海域試験の結果について報告する.

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Although computing technology has made inroads into home environments, it has yet to instigate a major shift in the design of homes or home activities. We posit that the next revolution of technology in the home will arise from technologies aimed at helping older adults maintain their independence and quality of life while helping avoid a transition to a more expensive, institutional setting. In this article, we describe three of our research projects that each tackle a different dimension to “aging in place.” In our work with the “Digital Family Portrait,” we examine the need for awareness between extended family members especially when family members are separated by great physical distance. In the “Cook's Collage,” we investigate the use of activity snapshots to aid a person in resuming an interrupted task. And finally in “Dude's Magic Box,” we explore ways to help grandchildren and grandparents communicate when face-to-face visits are rare.

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タカアミラーゼAは水溶液の状態で紫外線によって強く不活性化される.これは主としてシスチンの開裂酸化に伴う活性に必要な酵素蛋白の立体構造の破壊によるものであり,トリプトファン,チロシン,ヒスチジンなどの酸化も共役している.これらのことは光不活性化とこれに伴うアミノ酸の酸化量を定量することにより示される.光照射に伴う酸素吸収量はアミラーゼの場合と構成アミノ酸混合物とであまり差異がない.これは高分子形成およびconformation形成にあまり依存しないことを示すものである.アミノ酸の光酸化反応は励起1重項→3重項→溶媒捕捉準位の無輻動遷移によって作られる光電子による水の還元,これに溶存酸素がカップルして生じたHO₂と母体ラジカルとの酸化反応と考えられる.
このため常磁性イオンの共存により, 3重項←→1重項の遷移確率をコントロールすることにより光酸化反応をコントロ一ルできる.基質の存在は光不活性化反応を保護するが,これは光電子ないしHO₂に対し基質や分解産物が受容体として働くためであろうと考えられる.

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In April 2016, the Kumamoto earthquakes in Japan killed 50 people and injured more than 3,000. Because Japan is a primary tourist destination for Thai citizens, due in part to the current visa relaxation policy, many Thai people were visiting Japan when these earthquakes occurred. However, while a variety of public information related to the imminent danger and disaster response was broadcast and published, foreigners sometimes had little access to or understanding of local notices or instructions because of language barriers.

This study researches the evacuation process for Thai citizens – including tourists, students, and residents from Thailand – in the disaster-affected areas during the 2016 Kumamoto earthquakes. Through prompt collaboration among the relevant organizations, particularly the Royal Thai Embassy in Tokyo, the evacuation of Thai citizens was successfully completed within a few days. Moreover, some other foreigners were also assisted by the Thai embassy. This paper presents an overview of the evacuation process, including the critical role of information and communication technology (ICT) in disseminating information, transmitting rescue requests, and providing emergency communications. The lessons learned from these efforts can be applied in future natural disasters, especially for foreign organizations working in similar capacities overseas. In addition, this study suggests disaster preparedness and response guidelines for tourists when traveling overseas.

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ヒナの異なる部位から採取した食細胞(好異球とマクロファージ系細胞)の貧食活性と殺菌活性の程度を測定して,それらの細胞間における相違を明らかにしようとした。両食細胞では,採取された存在部位によって細胞の両活性の程度が異なることが明らかにされた。マクロファージ系列では,両活性は肺胞マクロファージにおいて他の細胞種(腹腔マクロファージと単球)に比較して有意に低かった。これらの結果は,ニワトリではマクロファージ系列における成熟度はそれらの貧食ならびに殺菌活性に必ずしも比例しないことを示唆した。このことは貧食活性が単球で最も高いことによって支持された。好異球では,腹腔の細胞の両活性は末梢血の細胞の活性よりも有意に高かった。現時点では,これら細胞間における活性の違いの意義あるいは相違が発生する機構は不明であるが,それらの可能性について考察した。

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