Virtualized Network Graph Design and Embedding Model to Minimize Provisioning Cost

The provisioning cost of a virtualized network (VN) depends on several factors, including the numbers of virtual routers (VRs) and virtual links (VLs), mapping of them on a substrate infrastructure, and routing of data traffic. An existing model, known as the virtual network embedding (VNE) model, determines the embedding of given VN graphs into the substrate infrastructure. When the resource allocation model of the VNE problem is adopted to a single-entity scenario, where a single entity fulfills the roles of both a service provider and an infrastructure provider, an issue of increased costs of VNs and access paths arise. This paper proposes a model for virtualized network graph design and embedding (VNDE) for the single-entity scenario. The VNDE model determines the number of VRs and a VN graph for each request in conjunction with embedding. The VNDE model also determines access paths that connect customer premises and VRs. We formulate the VNDE model as an integer linear programming (ILP) problem. We develop heuristic algorithms for the cases where the ILP problem cannot be solved in practical time. We evaluate the performance of the VNDE model on several networks, including an actual Japanese academic backbone network. Numerical results show that the proposed model designs suitable VN graphs and embeds them according to the volume of traffic demands and access path cost. Compared with the benchmark model, which is based on a classic VNE approach, the proposed model reduces the provisioning cost at most 28.7% in our examined scenarios

Flows Reduction Scheme Using Two MPLS Tags in Software-Defined Network

This paper proposes a scheme to reduce the number of flow entries permanently stored in an OpenFlow switch and the number of configuration messages from a controller in a software-defined network (SDN). In an SDN, a flow table in an OpenFlow switch is used to instruct packets. The flow table consists of flow entries decided by the controller. A flow request is sent from the OpenFlow switch to the controller if the incoming packet does not match any flow entry in the flow table. The controller\u27s central processing unit may be overloaded to handle user requests, since the user requests for different data types have been rapidly increasing. As a result, flow configuration in switches is delayed. Moreover, the control plane may be flooded by configuration messages of those requests. A scheme to permanently keep the flow entries in the switch can reduce the number of requests. However, a large number of permanent flow entries is required. Other switch features may be degraded, since there is not enough memory in the flow table to implement those features. In the proposed scheme, switches in the network are divided into multiple regions. In order to guide packets from sources to destinations, the flow table incorporating the concept of two multiprotocol label switching tags is re-designed. One tag directs a packet from a source switch to an edge switch in the destination region. The other tag directs the packet from that edge switch to another switch in the same region. A mathematical model for the proposed scheme is formulated as an integer linear programming to determine a set of switches in each region so that the total number of permanent flow entries in the network can be minimized. The performance of the proposed scheme is analyzed. Moreover, the proposed scheme is implemented and demonstrated via Japanese Science Information Network 5

X-ray Emission and Discharge Behavior on Three Kinds of Stacked Pyroelectric Single Crystal Units

タンタル酸リチウム単結晶を積層させたユニットの焦電特性に基づく放電およびX 線発生挙動について，結晶形状および真空度による相違を検討した．大気下での室温～400Kの温度変化サイクルに伴う放電現象はいずれも積層型結晶ユニット側面で観察された．放電回数は同一形状の板状単結晶を使用したユニットの方が形状不揃いの結晶を同一枚数積層させたときより5 倍多く，側面に絶縁グリースを塗布すると大幅に抑制された．放電は積層した板状結晶の間隙で起こり，加熱時には数秒から1 分間の短時間のスパイク状のX線が繰り返し発生した．X線の最高エネルギーは1Paと10-4Paでは相違なかったが，やや1Paの方がスパイク状X線の発生頻度が高かった．スパイク状のX 線発生および放電挙動の要因について議論した．Three types of stacked LiTaO3 single crystal units were assembled to investigate effects of shape of the single crystal and degree of ambient pressure on X-ray emission and discharge behavior based on the pyro electricity. Every instantaneous emission of visible light due to discharge occurred at the side of stacked crystals during heating and cooling cycle between room temperature and 400 K under atmospheric pressure. Discharge frequency on a stacked unit made of equal-sized four pieces (type-A) was five times more than that on a unit made of irregularlysized pieces (type-C). Discharge occurred possibly at narrow gap between two pieces of platelike single crystal. During heating process up to ca. 400 K under 1 or 10 - 4 Pa, spike-like X-ray emission for a few seconds through one minute occurred repeatedly on both type-A and -C units. The maximum energy of emitted X-ray was independent on both degree of vacuum and shape of stacked plate-like LiTaO3 single crystal. Discharge on type-A unit was suppressed by coating of stacked crystals with dielectric grease whereas high voltage generated on the coated unit. Origin of spike-like X-ray emission and discharge on stacked LiTaO3 units was discussed

Single tag scheme for segment routing in software-defined network

This paper proposes a scheme to reduce a size of a packet header for a segment routing (SR) scheme in a software-defined network (SDN). The SR scheme inserts a segment identification (SID) list into the packet header to indicate a path for the source–destination pair of the packet. The path can be split into different segments to suit the service requirement and the segments are carried by the SID-list whose length increases with the number of segments. This also increases the packet overhead, and an additional packet is needed if the packet length exceeds the maximum transmission unit (MTU). Moreover, it may not be possible to implement SR in SDN due to the limited number of stacked labels provided by the switch vendor. In the proposed scheme, the SID-list is replaced by a single tag to indicate a node edge, called a swapping node. The tag is replaced by a new tag at the swapping node. With this scheme, the size of SID-list is fixed and does not vary with the number of segments, and no additional packets are required. A mathematic model to balance the number of flow entries in each swapping node is introduced by minimizing the maximum number of flow entries in each swapping node over the network. We implement the proposed scheme on the transmission-Japan science information network (SINET5) and demonstrate confirms its functionality

Proteomic Study of Retinal Proteins Associated with Transcorneal Electric Stimulation in Rats

Background. To investigate how transcorneal electric stimulation (TES) affects the retina, by identifying those proteins up- and downregulated by transcorneal electric stimulation (TES) in the retina of rats. Methods. Adult Wistar rats received TES on the left eyes at different electrical currents while the right eyes received no treatment and served as controls. After TES, the eye was enucleated and the retina was isolated. The retinas were analyzed by proteomics. Results. Proteomics showed that twenty-five proteins were upregulated by TES. The identified proteins included cellular signaling proteins, proteins associated with neuronal transmission, metabolic proteins, immunological factors, and structural proteins. Conclusions. TES induced changes in expression of various functional proteins in the retina

Generation of four induced pluripotent stem cell lines (FHUi003-A, FHUi003-B, FHUi004-A and FHUi004-B) from two affected individuals of a familial neurohypophyseal diabetes insipidus family

Four disease-specific induced pluripotent stem cell (iPSC) lines were respectively derived from peripheral blood mononuclear cells of two affected individuals in a family affected by familial neurohypophyseal diabetes insipidus carrying the c.314G>C mutation. The expression of pluripotency markers (NANOG, OCT4, and SOX2), maintenance of a normal karyotype, absence of episomal vectors used for iPSC generation, and presence of the original pathogenic mutation were confirmed for each iPSC line. The ability to differentiate into three germ layers was confirmed by a teratoma formation assay. These iPSC lines can help in disease recapitulation in vitro using organoids and elucidation of disease mechanisms

Degradation of Mutant Protein Aggregates within the Endoplasmic Reticulum of Vasopressin Neurons

Misfolded or unfolded proteins in the ER are said to be degraded only after translocation or isolation from the ER. Here, we describe a mechanism by which mutant proteins are degraded within the ER. Aggregates of mutant arginine vasopressin (AVP) precursor were confined to ER-associated compartments (ERACs) connected to the ER in AVP neurons of a mouse model of familial neurohypophysial diabetes insipidus. The ERACs were enclosed by membranes, an ER chaperone and marker protein of phagophores and autophagosomes were expressed around the aggregates, and lysosomes fused with the ERACs. Moreover, lysosome-related molecules were present within the ERACs, and aggregate degradation within the ERACs was dependent on autophagic-lysosomal activity. Thus, we demonstrate that protein aggregates can be degraded by autophagic-lysosomal machinery within specialized compartments of the ER

合併症を有するB型大動脈解離に対するステントグラフト内挿術における腎動脈に対する治療戦略 : 多施設共同研究

Background: Management of abdominal branches associated with Stanford type B aortic dissection is controversial without definite criteria for therapy after thoracic endovascular aortic repair (TEVAR). This is in part due to lack of data on natural history related to branch vessels and their relationship with the dissection flap, true lumen, and false lumen. Purpose: To investigate the natural history of abdominal branches after TEVAR for type B aortic dissection and the relationship between renal artery anatomy and renal volume as a surrogate measure of perfusion. Materials and Methods: This study included patients who underwent TEVAR for complicated type B dissection from January 2012 to March 2017 at 20 centers. Abdominal aortic branches were classified with following features: patency, branch vessel origin, and presence of extension of the aortic dissection into a branch (pattern 1, supplied by the true lumen without branch dissection; pattern 2, supplied by the true lumen with branch dissection, etc). The branch artery patterns before TEVAR were compared with those of the last follow-up CT (mean interval, 19.7 months) for spontaneous healing. Patients with one kidney supplied by pattern 1 and the other kidney by a different pattern were identified, and kidney volumes over the course were compared by using a simple linear regression model. Results: Two hundred nine patients (mean age ± standard deviation, 66 years ± 13; 165 men and 44 women; median follow-up, 18 months) were included. Four hundred fifty-nine abdominal branches at the last follow-up were evaluable. Spontaneous healing of the dissected branch occurred in 63% (64 of 102) of pattern 2 branches. Regarding the other patterns, 6.5% (six of 93) of branches achieved spontaneous healing. In 79 patients, renal volumes decreased in kidneys with pattern 2 branches with more than 50% stenosis and branches supplied by the aortic false lumen (patterns 3 and 4) compared with contralateral kidneys supplied by pattern 1 (pattern 2 vs pattern 1: −16% ± 16 vs 0.10% ± 11, P = .002; patterns 3 and 4 vs pattern 1: −13% ± 14 vs 8.5% ± 14, P = .004). Conclusion: Spontaneous healing occurs more frequently in dissected branches arising from the true lumen than in other branch patterns. Renal artery branches supplied by the aortic false lumen or a persistently dissected artery with greater than 50% stenosis are associated with significantly greater kidney volume loss.博士（医学）・乙第1461号・令和2年6月30日Copyright © 2019 by authors and RSNA. This work is licensed under the Creative Commons Attribution International License (CC BY-NC-ND 4.0). https://creativecommons.org/licenses/by-nc-nd/4.0/