An extrusion method of tube with spiral inner fins by utilizing generation of spiral outer fins/grooves

This paper presents a new extrusion method for fabrication of a tube with spiral inner fins. The spiral fins are formed by utilizing the generation of spiral outer fins or grooves, which drive the metal to circumferentially move with twist deformation. The effect of the outer fins/grooves is examined for realizing the circumferential metal flow. The position of the mandrel has an ability to flexibly control the spiral angle. This method would drastically enhance the productivity and reduce the manufacturing cost, as the tube would be manufactured directly from a billet through only one process

骨形成細胞シートは血管柄付き人工骨内での骨形成および血管形成を促進させる

BACKGROUND: The regeneration of large, poorly vascularized bone defects remains a significant challenge. Although vascularized bone grafts promote osteogenesis, the required tissue harvesting causes problematic donor-site morbidity. Artificial bone substitutes are promising alternatives for regenerative medicine applications, but the incorporation of suitable cells and/or growth factors is necessary for their successful clinical application. The inclusion of vascular bundles can further enhance the bone-forming capability of bone substitutes by promoting tissue neovascularization. Little is known about how neovascularization occurs and how new bone extends within vascularized tissue-engineered bone, because no previous studies have used tissue-engineered bone to treat large, poorly vascularized defects. METHODS: In this study, the authors developed a novel vascularized tissue-engineered bone scaffold composed of osteogenic matrix cell sheets wrapped around vascular bundles within β-tricalcium phosphate ceramics. RESULTS: Four weeks after subcutaneous transplantation in rats, making use of the femoral vascular bundle, vascularized tissue-engineered bone demonstrated more angiogenesis and higher osteogenic potential than the controls. After vascularized tissue-engineered bone implantation, abundant vascularization and new bone formation were observed radially from the vascular bundle, with increased mRNA expression of alkaline phosphatase, bone morphogenetic protein-2, osteocalcin, and vascular endothelial growth factor-A. CONCLUSION: This novel method for preparing vascularized tissue-engineered bone scaffolds may promote the regeneration of large bone defects, particularly where vascularization has been compromised.博士（医学）・甲第652号・平成28年3月15日Copyright © 2016 American Society of Plastic Surgeons All rights reserved.This is a non-final version of an article published in final form in "http://dx.doi.org/10.1097/PRS.0000000000002079

冷凍保存骨芽細胞シートの骨形成能評価

Cryopreservation of tissue engineered bone (TEB), whilst maintaining its osteogenic ability, is imperative for large-scale clinical application. We previously reported a novel cell transplantation method, in which bone-marrow-derived mesenchymal stem cells (BMSCs) were cultured to confluence and differentiated down the osteogenic lineage to form osteogenic matrix cell sheets (OMCS). OMCS have high alkaline phosphatase (ALP) activity and osteocalcin (OC) contents and can be easily used for producing TEB. The aim of the present study was to investigate whether TEB produced by cryopreserved OMCS maintains sufficient osteogenic potential in vivo. OMCS were prepared and divided into three groups according to storage period of cryopreservation (fresh (no cryopreservation), 4 week and 12 week cryopreservation groups). OMCS were cryopreserved by storage in freezing medium (Cell Banker 1®) at -80 °C. Cryopreserved OMCSs were rapidly thawed at room temperature and wrapped around Hydroxyapatite (HA) scaffolds prior to implantation into subcutaneous sites in rats, to determine their in vivo bone-forming capability. The constructs were harvested 4 weeks after transplantation and examined histologically and biochemically. Histological analysis of the constructs showed extensive bone formation in the HA pores with high ALP activity and OC content detected in the cryopreservation groups. The present study clearly indicates that cryopreserved/thawed OMCS are still capable of producing mineralized matrix on scaffolds, resulting in bone formation. This cryopreservation technique could be applied for hard tissue reconstruction to ease the cell preparation method prior to time of use.博士（医学）・甲第607号・平成25年11月27

Control and visualization system for managed self-organization network.

Abstract-We propose the managed self-organizing network concept considering the unexpected network changes caused by the future applications, and implement the control and visualization system for it. In the managed self-organizing network, multiple virtual networks are accommodated on a single optical infrastructure. Each virtual network is controlled based on self-organizing mechanism by attractor selection algorithm that models behavior where living organisms adapt to unknown changes in their surrounding environments. On the other hand, the physical resource management server dynamically manages the resource allocation for each virtual network to optimize the utilization of total network resources. Our implemented system efficiently visualizes the behavior of managed self-organizing network with time variability, and network filtering and clustering functions are implemented for visualization of large and multiple virtual networks. Index Terms-managed self-organizing network, network virtualizatio

How did Japanese teachers deal with COVID-19 in their lessons?: The case studies of two teachers

This article illustrates how two Japanese teachers design and implement a unit related to COVID-19 for promoting teaching controversial issues in Japan. We discovered the following two implications for achieving the aim: (a) improving teachers’ abilities of explaining how the issues are necessary and important in school education and (b) enhancing the ability of gatekeeping of teachers. Particularly, the ability of curriculum management is significant for teaching controversial issues.本研究は，JSPS科研費19K14239の助成，および令和二年度教育学部共同研究プロジェクト「ポストコロナの学校教育」の提起する学術知共創の可能性と課題」の支援を受けたものである

D-dimer trends predict recurrent stroke in patients with cancer-related hypercoagulability

Abstract Introduction: In patients with cancer-associated hypercoagulability (CAH)-related stroke, D-dimer trends after anticoagulant therapy may offer a biomarker of treatment efficacy. The purpose of this study was to clarify the association between D-dimer trends and recurrent stroke after anticoagulant therapy in patients with CAH-related stroke. Methods: We performed retrospective cohort study of consecutive patients with CAH-related stroke at two stroke centers from 2011 through 2020. The ratio of post-treatment to pre-treatment D-dimer levels (post/pre ratio) was used as an indicator of D-dimer trends after anticoagulant therapy. Fine–Gray models were used to evaluate the association between post/pre ratio and recurrent stroke. Results: Among 360 acute ischemic stroke patients with active cancer, 73 patients with CAH-related stroke were included in this study. Recurrent stroke occurred in 13 patients (18%) during a median follow-up time of 28 days (interquartile range, 11–65 days). Multivariate analysis revealed that high post/pre ratio was independently associated with recurrent stroke (per 0.1 increase: hazard ratio 2.20, 95% confidence interval 1.61–3.01, p=0.012). Discussion and Conclusion: D-dimer levels after anticoagulant therapy were associated with recurrent stroke in CAH-related stroke patients. Patients with neutral trends in high D-dimer levels after anticoagulant therapy were at high risk of recurrent stroke

広島大学考古学研究室所蔵の西アジア青銅柄鉄剣をめぐって

いわゆる「鉄芯」入り青銅剣（バイメタル青銅剣）とされてきた広島大学考古学研究室所蔵資料についての再調査を行う。バイメタル青銅剣は、紀元前800～1200ごろ年にカスピ海南部の山岳地帯において出現する金属器で、鉄利用の初期の様相を明らかにするうえで重要である。西アジア北部地域における鉄製利器の祖型として、鉄製棒状部品を内蔵する青銅剣（「鉄芯」入り青銅剣）の存在が指摘され、編年・機能研究が行われてきた。しかし、当該資料はおそらく現代において改変された青銅柄鉄剣であったことが判明した。他機関所蔵品の知見も加味すると、研究対象の多くに同様の可能性があり、「鉄芯入り」青銅剣を前提に導かれたこれまでの知見や議論は根本的な見直しを迫られることになる。紀元前2000年紀の終わりにカスピ海周辺に出現する「鉄芯入り」青銅剣が実は青銅柄鉄剣であったわけであり、それ以前に鉄製利器の導入期といった、より原初的な初期鉄器の実態がある可能性が高くなる。今回の再調査はそうした研究の脆弱性を露呈し、西アジアにおける初期鉄器時代の議論を転換する結果となった

Mesospheric CO2 ice clouds on Mars observed by Planetary Fourier Spectrometer onboard Mars Express

We investigate mesospheric CO2 ice clouds on Mars detected by the Planetary Fourier Spectrometer (PFS) onboard Mars Express (MEx). The relatively high spectral resolution of PFS allows firm identification of the clouds' reflection spike. A total of 279 occurrences of the CO2 ice clouds features has been detected at the bottom of 4.3 μm CO2 band from the MEx/PFS data during the period from MY27 to MY32. 115 occurrences out of them are also confirmed by simultaneous observations by MEx/OMEGA imaging spectrometer. The spatial and seasonal distributions of the CO2 ice clouds observed by PFS are consistent with the previous studies: the CO2 ice clouds are only observed between Ls=0° and 140° at distinct longitudinal corridors around the equatorial region (±20°N). The CO2 ice clouds are preferentially detected at local time between 15-17h. The relatively high spectral resolution of PFS allows us to investigate the spectral shape of the CO2 ice clouds features. The CO2 ice clouds reflection spike is peaked between 4.24 and 4.29 μm, with no evidence of the secondary peak at 4.32-4.34 μm observed by MEx/OMEGA (Määttänen et al., 2010). In most of the cases (about 75%), the peak is present between 4.245 and 4.255 μm. Moreover, small secondary peaks are found around 4.28 μm (about 15 occurrences). These spectral features cannot be reproduced by the synthetic spectra with the assumption of a spherical particle shape in our radiative transfer model (DISORT). This can be due to the fact that the available CO2 ice reflective indexes are either inaccurate or inappropriate for the mesospheric temperatures, or that the particle shape is not spherical. Accurate measurements of the reflective index depending on temperature and detailed comparison with the model taking into account non-spherical shapes will give a clue to solve this issue

Host Prostaglandin E2-EP3 Signaling Regulates Tumor-Associated Angiogenesis and Tumor Growth

Nonsteroidal antiinflammatories are known to suppress incidence and progression of malignancies including colorectal cancers. However, the precise mechanism of this action remains unknown. Using prostaglandin (PG) receptor knockout mice, we have evaluated a role of PGs in tumor-associated angiogenesis and tumor growth, and identified PG receptors involved. Sarcoma-180 cells implanted in wild-type (WT) mice formed a tumor with extensive angiogenesis, which was greatly suppressed by specific inhibitors for cyclooxygenase (COX)-2 but not for COX-1. Angiogenesis in sponge implantation model, which can mimic tumor-stromal angiogenesis, was markedly suppressed in mice lacking EP3 (EP3−/−) with reduced expression of vascular endothelial growth factor (VEGF) around the sponge implants. Further, implanted tumor growth (sarcoma-180, Lewis lung carcinoma) was markedly suppressed in EP3−/−, in which tumor-associated angiogenesis was also reduced. Immunohistochemical analysis revealed that major VEGF-expressing cells in the stroma were CD3/Mac-1 double-negative fibroblasts, and that VEGF-expression in the stroma was markedly reduced in EP3−/−, compared with WT. Application of an EP3 receptor antagonist inhibited tumor growth and angiogenesis in WT, but not in EP3−/−. These results demonstrate significance of host stromal PGE2-EP3 receptor signaling in tumor development and angiogenesis. An EP3 receptor antagonist may be a candidate of chemopreventive agents effective for malignant tumors