TMTTF系の電荷秩序転移及び超伝導転移の理論的調査

京都大学新制・課程博士博士(理学)甲第24176号理博第4867号京都大学大学院理学研究科化学専攻(主査)准教授 倉重 佑輝, 教授 谷村 吉隆, 教授 吉村 一良学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDGA

Low-Congestion Shortcut and Graph Parameters

Distributed graph algorithms in the standard CONGEST model often exhibit the time-complexity lower bound of Omega~(sqrt{n} + D) rounds for many global problems, where n is the number of nodes and D is the diameter of the input graph. Since such a lower bound is derived from special "hard-core" instances, it does not necessarily apply to specific popular graph classes such as planar graphs. The concept of low-congestion shortcuts is initiated by Ghaffari and Haeupler [SODA2016] for addressing the design of CONGEST algorithms running fast in restricted network topologies. Specifically, given a specific graph class X, an f-round algorithm of constructing shortcuts of quality q for any instance in X results in O~(q + f)-round algorithms of solving several fundamental graph problems such as minimum spanning tree and minimum cut, for X. The main interest on this line is to identify the graph classes allowing the shortcuts which are efficient in the sense of breaking O~(sqrt{n}+D)-round general lower bounds. In this paper, we consider the relationship between the quality of low-congestion shortcuts and three major graph parameters, chordality, diameter, and clique-width. The main contribution of the paper is threefold: (1) We show an O(1)-round algorithm which constructs a low-congestion shortcut with quality O(kD) for any k-chordal graph, and prove that the quality and running time of this construction is nearly optimal up to polylogarithmic factors. (2) We present two algorithms, each of which constructs a low-congestion shortcut with quality O~(n^{1/4}) in O~(n^{1/4}) rounds for graphs of D=3, and that with quality O~(n^{1/3}) in O~(n^{1/3}) rounds for graphs of D=4 respectively. These results obviously deduce two MST algorithms running in O~(n^{1/4}) and O~(n^{1/3}) rounds for D=3 and 4 respectively, which almost close the long-standing complexity gap of the MST construction in small-diameter graphs originally posed by Lotker et al. [Distributed Computing 2006]. (3) We show that bounding clique-width does not help the construction of good shortcuts by presenting a network topology of clique-width six where the construction of MST is as expensive as the general case

Gene transfer of metalloproteinase transin induces aberrant behavior of cultured mesangial cells

Gene transfer of metalloproteinase transin induces aberrant behavior of cultured mesangial cells. The aim of the present study is to clarify whether the cellular expression of a matrix-degrading metalloproteinase, transin, alters the behavior of cultured mesangial cells (MCs). The cDNA encoding rat transin was introduced into rat MCs and transcribed under the control of a Rous sarcoma virus promoter. The resulting transfectants were then investigated for cell shape, migration, proliferation, and expression of genes associated with matrix metabolism. Northern blot analysis routinely detected the transin transcript in two separate transfectants, MeTRN2 and MeTRN5. Transin expression was strong in MeTRN2, moderate in MeTRN5, but absent in mock transfectants. Immunoblot analysis revealed that these transin transfectants synthesized 59 and 62kDa molecules, which correspond to transin gene products. Casein digestion assay detected enhanced proteolytic activity in MeTRN2 and MeTRN5. Microscopically, the transfected cells were somewhat elongated with accentuated margins compared with mock transfectants. [3H]-thymidine uptake studies revealed accelerated growth of the transfectants on a plastic substratum as well as within gel matrix. The migration of the transfectants into gel matrix was also significantly enhanced compared with that of mock transfectants. No obvious alteration, however, was found in transcripts of procollagen α1(IV), laminin B2, or the metalloproteinase inhibitor TIMP. We hypothesize that the metalloproteinase transin has a potential for affecting the behavior of MCs and contributing to the pathogenesis of glomerular injury

Uniform Distribution On Pachinko

Pachinko is a japanese mechanical gambling game similar to pinball. Recently, Akitaya et al. proposed several mathematical models of Pachinko. A number of pins are spiked in a field. A ball drops from the top-side end of the playfield, and falls down. In the 50-50 model, if the ball hits a pin, it moves to the left or right of the pin with equal probability. An arrangement of pins generates a distribution of the drop probability over all columns. We consider the problem of generating uniform distributions. Akitaya et al. show that (1/2^{{a}})-uniform distribution is possible for {a} in {0,1,2,3,4} and conjectured that it is possible for any positive integer a. In this paper, we show that the conjecture is true by a constructive way

2,3-Dimeth­oxy-5,12-tetra­cenequinone

The mol­ecule of the title compound, C20H14O4, is approximately planar [maximum deviation 0.168 (2) Å]. The two meth­oxy groups are slightly twisted relative to the plane of the 5,12-tetra­cenequinone system, with twist angles of 3.3 (3) and 5.6 (2)°. All O atoms are involved in intermolecular C—H⋯O inter­actions and the mol­ecules are arranged into slipped face-to-face stacks along the b axis via π–π inter­actions with an inter­planar distance of 3.407 (2) Å

Endoscopy in Nonvariceal UGI Bleeding

Nonvariceal upper gastrointestinal (GI) bleeding is one of the most common reasons for hospitalization and a major cause of morbidity and mortality worldwide. Recently developed endoscopic devices and supporting apparatuses can achieve endoscopic hemostasis with greater safety and efficiency. With these advancements in technology and technique, gastroenterologists should have no concerns regarding the management of acute upper GI bleeding, provided that they are well prepared and trained. However, when endoscopic hemostasis fails, endoscopy should not be continued. Rather, endoscopists should refer patients to radiologists and surgeons without any delay for evaluation regarding the appropriateness of emergency interventional radiology or surgery