Cold Positions of the Restricted Wythoff\u27s Game

Wythoff\u27s game is a kind of 2-pile Nim game, which admits taking the same number of stones from both piles. It differs only a little from the 2-pile Nim game, but their winning strategies are quite different from each other. Amazingly the winning strategy of Wythoff\u27s game is directly related to a real number, specifically the golden ratio. In this paper we add two restrictions to this game, and investigate the winning strategy of the revised game

Factors Affecting Postoperative Hearing Results in Type IV Tympanoplasty: Preliminary Study of the Influence of External Auditory Canal Packing Material

[Background] Postoperative hearing results of type IV tympanoplasty have been shown to have poorer results than other reconstruction techniques. There are numerous reports evaluating the factors for hearing improvement. This preliminary study aimed to analyze and determine the factors that affect hearing results. [Methods] A total of 80 patients who underwent type IV tympanoplasty were evaluated to participate in this study. The medical records of the candidate patients were collected retrospectively. Fifty out of the 80 recruited patients were excluded due to the following reasons: they could not be followed-up for more than a year after the final operation, their initial surgery was not performed in our department, or they needed a revision surgery. The pre-, intra-, and postoperative factors were evaluated and analyzed using EZR software. Cases were divided into two groups according to postoperative hearing results, and each factor was analyzed univariately. The explanatory variables included in the multivariate analysis were the variables that satisfied P < 0.1 in the univariate analysis. Furthermore, all cases were divided into two groups according to the qualitative variables that showed significant difference in the multivariate analysis, and the background factors were evaluated. [Results] The results of univariate analysis showed P < 0.1 for ‘Age’ and ‘Material of external auditory canal (EAC) packing’. Multivariate analysis showed P < 0.05 for both. The comparison between the two packing material groups showed that the gauze group was more likely to have improved hearing than Spongel? group, and the ossicular chain condition of the gauze group was maintained better. [Conclusion] ‘Age’ and ‘Material of EAC packing’ were considered to be significant factors affecting the postoperative hearing results. The selection and use of packing materials that provide stability should be considered to obtain better postoperative hearing results in type IV tympanoplasty

A Case of Gorham-Stout Disease Treated with Fistula Closure by Transmeatal Approach

Gorham-Stout disease, a rare and intractable disease of unknown etiology, causes systemic bone lysis and replacement with lymphoid tissue. Here, we report a case of Gorham-Stout disease with cerebrospinal fluid leakage in a 16-year-old boy. The patient complained of nasal discharge, right ear obstruction, fever, and headache. A computed tomography scan of the head showed osteolysis around the right internal carotid artery, vestibule, and cochlea and osteolytic changes in the left parietal bone. It was suggested that the patient had bacterial meningitis owing to the leakage of cerebrospinal fluid from the fistula caused by the temporal bone osteolysis. He was treated with meropenem, and a transmeatal fistula closure and a bone biopsy of the left parietal bone were performed. Intraoperatively, osteolysis was observed on the promontory and around the internal carotid artery. The fistula was closed by dense filling and compression around the fistula, in the middle ear cavity, and in the external auditory canal. The symptoms disappeared after the surgery. Bone biopsy showed the presence of a lymphangioma, and Gorham-Stout disease was diagnosed. Prophylactic bisphosphonate therapy was initiated. A 4-year follow-up revealed no progression of the disease

Hemostatic Control with Gelatin Sponge and Quantum Molecular Resonance Coagulation in a Case of Glomus Tympanicum

Surgical removal of tumor is the primary treatment of choice for glomus tympanicum (GT). However, because the tumor has abundant blood flow, bleeding control is crucial, and preoperative embolization may be performed. Here, we report the case of a 46-year-old female who visited our hospital with a complaint of right pulsatile tinnitus. A red pulsatile mass was found in the right tympanic cavity, and she was diagnosed with class B1 GT and subsequently underwent surgical treatment. We judged that bleeding could be controlled by intratympanic cavity manipulation alone and decided to perform transmeatal tumor resection without preoperative arterial embolization. After creating a tympanomeatal flap and performing an atticotomy, some pieces of Spongel® were inserted between the tumor and the tympanic wall. The Spongel® absorbed the blood and created a space between the tumor and tympanic wall, which allowed for the insertion of the tip of the Vesalius® handpiece to coagulate the tumor. The coagulation caused the tumor to shrink, thereby widening the space and allowing for further resection. Although the surgical manipulation caused bleeding, complete resection was achieved by the application of Spongel® and coagulation with Vesalius®. Since the tip of the Vesalius® was not burned, hemostasis was successfully achieved, and the operation proceeded while maintaining a clear field of view. There was little bleeding and no postoperative complications. The patient was discharged on the sixth postoperative day. One year after surgery, pure tone audiometry showed no change in the level of bone conduction. Spongel® and Vesalius® are useful tools that allow to safely perform surgeries even in narrow spaces such as the tympanic cavity

A Case of Cochlear Implantation in a Patient with Superficial Siderosis

Superficial siderosis is a disease in which iron from hemoglobin is deposited in the central nervous system, resulting in conditions such as progressive sensorineural hearing loss, cerebellar ataxia, dementia, and pyramidal signs. A 30-year-old man with superficial siderosis received a cochlear implant in the left ear, which had shown complete hearing loss. Good auditory responses were obtained at 14 days after implantation. The postoperative average hearing level with the cochlear implant was 56.7 dB at 3 months and 55.0 dB at 6 months. However, the patient showed gradual hearing loss, and the dynamic range changed each time the electrode parameters were adjusted. To assess residual hearing ability, single-photon emission computed tomography was performed together with an assessment of electrical auditory brainstem response, which showed a good response and increased blood flow in both the temporal lobes. Based on this result, we asked the patient to continue using the cochlear implant to see whether a perception of speech response would be obtained. However, the patient discontinued using the cochlear implant because he could not hear satisfactorily. Hearing outcomes after cochlear implant surgery for patients with superficial siderosis are not necessarily good. Therefore, the possibility of unsatisfactory Results should be fully explained before recommending this surgery to patients

Targeting cancer cell-specific RNA interference by siRNA delivery using a complex carrier of affibody-displaying bio-nanocapsules and liposomes

BACKGROUND: Small interfering RNA (siRNA) has attracted attention in the field of nucleic acid medicine as a RNA interference (RNAi) application that leads to gene silencing due to specific messenger RNA (mRNA) destruction. However, since siRNA is unstable in blood and unable to cross the cell membrane, encapsulation of siRNA into a carrier is required. RESULTS: In this study, we used a carrier that combined Z(HER2)-displaying bio-nanocapsule (derived from hepatitis B virus surface antigen) and liposomes in a complex in order to investigate the feasibility of effective and target-cell-specific RNAi applications. As a result, by observing RNAi only in HER2-expressing breast cancer cells, using our proposed methodology, we successfully demonstrated target-cell-specific delivery and effective function expression of siRNA. CONCLUSIONS: These findings show that, in the field of nucleic acid medicine, Z(HER2)-BNC/LP can be a useful carrier for siRNA delivery, and could also become a useful tool for gene silencing and to accomplish protein knock-down

Dynamic Programming for the Subset Sum Problem

The subset sum problem is a basic problem in the field of theoretical computer science, especially in the complexity theory [3]. The input is a sequence of positive integers and a target positive integer. The task is to determine if there exists a subsequence of the input sequence with sum equal to the target integer. It is known that the problem is NP-hard [2] and can be solved by dynamic programming in pseudo-polynomial time [1]. In this article we formalize the recurrence relation of the dynamic programming.This work was supported by JSPS KAKENHI Grant Numbers JP16K00033, JP17K00013 and JP17K00183.Hiroshi Fujiwara - Shinshu University, Nagano, JapanHokuto Watari - Nagano Electronics Industrial Co., Ltd., Chikuma, JapanHiroaki Yamamoto - Shinshu University, Nagano, JapanMichael R. Garey and David S. Johnson. Computers and Intractability: A Guide to the Theory of NP-Completeness. W. H. Freeman & Co., New York, NY, USA, 1979. ISBN 0716710447.Richard M. Karp. Reducibility among combinatorial problems. In Miller et al. [3], pages 85–103. ISBN 978-1-4684-2001-2. doi:10.1007/978-1-4684-2001-2_9.Raymond E. Miller, James W. Thatcher, and Jean D. Bohlinger, editors. Complexity of Computer Computations, 1972. Springer US. ISBN 978-1-4684-2001-2. doi:10.1007/978-1-4684-2001-2_9.Wojciech A. Trybulec. Non-contiguous substrings and one-to-one finite sequences. Formalized Mathematics, 1(3):569–573, 1990.899

分子動力学法を用いた生体高分子のトリチウム誘起壊変 シミュレーションと精度評価のための実験系の構築

トリチウムの生体への影響は，トリチウム由来の線の飛程が水中や細胞中で数ミクロン程度と短いため，外部被ばくが問題となることはなく，内部被ばくに対する防護が重要となってくる．国内外の研究者によりマウスなどを用いての研究など同分野の研究は広く行われてきている．一方，我々は現実の生体そのものの階層ではなく，原子分子レベルの階層に絞り，トリチウムが生体分子（DNA）へ与える影響を分子動力学シミュレーションで解き明かすと共に，それにより生体分子の損傷機構解明をめざしてきた．さらに，シミュレーションと相補的に，蛍光顕微鏡を用いたDNA 一分子観察法によりトリチウム水中でのDNA の二本鎖切断メカニズムの測定も行ってきている．このような研究の試みは，複雑な生命体そのものに短絡的に結びつけるには，いまだ隔たりがあるが，生体分子そのもののトリチウム影響の必要な基礎情報の蓄積をめざすものである．このように核融合研究で培ってきたシミュレーション技法・測定技法を用いた「トリチウムの影響評価」の試みを紹介する

肝内胆管癌におけるIDH変異の意義

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 國土 典宏, 東京大学教授 黒川 峰夫, 東京大学准教授 森川 鉄平, 東京大学准教授 池上 恒雄, 東京大学講師 赤澤 宏University of Tokyo(東京大学