MARTENS' DIMENSION THEOREM FOR CURVES OF EVEN GONALITY

Kato, Takao Korean Mathematical Society 2002 대한수학회지 Vol.39 No.5

For a smooth projective irreducible algebraic curve C of odd gonality, the maximal possible dimension of the variety of special linear systems ${W^r}_d$(C) is d-3r by a result of M. Coppens et at. [4]. This bound also holds if C does not admit an involution. Furthermore it is known that if dim ${W^r}_d(C)qeq$ d-3r-1 for a curve C of odd gonality, then C is of very special type of curves by a recent progress made by G. Martens [11] and Kato-Keem [9]. The purpose of this paper is to pursue similar results for curves of even gonality which does not admit an involution.

ANALYTIC SMOOTHING EFFECT AND SINGLE POINT SINGULARITY FOR THE NONLINEAR SCHRODINGER EQUATIONS

Kato, Keiichi,Ogawa, Takayoshi Korean Mathematical Society 2000 대한수학회지 Vol.37 No.6

We show that a weak solution of the Cauchy problem for he nonlinear Schrodinger equation, {i∂(sub)t u + ∂$^2$(sub)x u = f(u,u), t∈(-T,T), x∈R, u(0,x) = ø(x).} in the negative solbolev space H(sup)s has a smoothing effect up to real analyticity if the initial data only have a single point singularity such as the Dirac delta measure. It is shown that for H(sup)s (R)(s>-3/4) data satisfying the condition (※Equations, See Full-text) the solution is analytic in both space and time variable. The argument is based on the recent progress on the well-posedness result by Bourgain [2] and Kenig-Ponce-Vega [18] and previous work by Kato-Ogawa [12]. We give an improved new argument in the regularity argument.

Martens' dimension theorem for curves of even gonality

Takao Kato 대한수학회 2002 대한수학회지 Vol.39 No.5

For a smooth projective irreducible algebraic curve C of oddgonality, the maximal possible dimension of the variety ofspecial linear systems W^r_d(C) is d-3r by a result of M.Coppens et al. cite{CKM}. This bound also holds if C does notadmit an involution. Furthermore it is known that if dimW^r_d(C)ge d-3r-1 for a curve C of odd gonality, then C isof very special type of curves by a recent progress made by G.Martens cite{Ma} and Kato-Keem cite{KK}. The purpose of thispaper is to pursue similar results for curves of even gonalitywhich does not admit an involution.

First Trial of Cervical Cytology in Healthy Women of Urban Laos using by Self-sampling Instrument

Nabandith, Viengvansay,Pholsena, Vatsana,Mounthisone, Phouthasone,Shimoe, Kyoko,Kato, Saiko,Aoki, Kunio,Noda, Sadamu,Takamatsu, Reika,Saio, Masanao,Yoshimi, Naoki Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9

Cervical cancer is the most common cancer in Laos women and a screening programme, even with the PAP smear test (PAP test), has yet to be established for routine use. The Pap test is accepted as the most appropriate for cervical cancer screening in some settings but it is not commonly available in Laos hospitals, because there are few cytopathologists and gynecologists have little experience. As a pilot program, seminars for the PAP test were given in 2007 and 2008, and then PAP tests were carried out using self-sampling instrument (Kato's device) with 200 healthy volunteers in Setthathirath hospital, Laos, in 2008. The actual examination number was 196, divided into class I 104 (53.1%), class II 85 (43.3%), class IIIa 4 (2.0%), class IIIb 1 (0.5%), and class V 1 (0.5%) by modified Papanicolau classification. Four cases had menstruation. There were 6 cases with epithelial cell abnormalities including malignancy. There were 7 cases with fungus and 2 cases with trichomonas in Class II. More than 70% volunteers felt comfortable with the Kato's device and wanted to use it next time, because of the avoidance of the embarrassment and a low cost as compared with pelvic examination by gynecologists. This first trial for PAP test for healthy Laos women related to a hospital found three percent to have abnormal cervical epithelial cells. Therefore, this appraoch using a self-sampling device suggests that it should be planned for cervical cancer prevention in Laos.

日本에서의 채권법개정 10년사

加藤雅信(Kato, Masanobu),김상수(Kim, Sang Soo) 서강대학교 법학연구소 2018 서강법률논총 Vol.7 No.1

일본에서는 최근 채권법개정이 국회를 통과하였다. 이번 개정은 10년 정도의 시간이 걸리며 이루어진 것인데, 그 개정과정에서는 많은 비판이 제기되고, 입법을 추진한 법무성의 의도와는 다른 개정이 되었다. 그러한 비판의 선두에 선건 이 논문의 저자이기도 한 일본의 저명 민법학자인 가또 마사노부(加藤雅信)교수이다. 가또 교수는 처음에는 법무성과 협력하면서 후반에는 법무성과 대립하면서 채권법개정 문제에 관여하였다. 그 채권법개정 과정을 이면에서 벌어진 일도 가미하며 리뷰하는 것이 이 연구의 주된 목적이기도 하다. 일본의 민법개정과정을 보면서 민법의 개정은 어떻게 하는 것이 좋은지 타산지석이 될 수 있을 것이다. 이번 일본의 민법개정은 결국 당초 의도되었던 법무성의 개정목적인 대목표에 한정하면 거의 완전히 사라져 버렸다. 법률의 성립이라는 최종국면은 추진파에게 있어 달성감에 젖어 있어야 할 장면인데 누구와 얘기하여도 그 달성감을 느낀 일이 없다. 물론 법안불성립으로 끝나지 않았음을 다행이라고 여기는 입장도 있다고 보는데, 그래도 해피하다고 하기 보다는 당초의 목표를 달성하지 못하고 겨우 체면을 지켰다는 의미라고 추측된다. 실로 쓸쓸한 법의 성립이었다. 국민에게 있어서도 상실만이었던 10년이 되었지만, 이 불행한 경험이 무엇보다도 앞으로의 행정과 정치를 담당하는 분들에게 타산지석으로서의 의미를 가짐을 지금은 바랄 뿐이다. 민법 제정 후 오랜 시간이 경과된 후의 민법대개정은 민법제정에 버금가는 매우 어려운 작업이 될 것이다. 일본에서의 민법대개정은 결국 시작단계와는 달리 많은 시간과 노력이 투입되었음에도 소개정으로 끝났다. 어떻게 개정하는 것이 좋은지, 이것은 모든 법개정에 적용되는 일이지만, 시민생활의 기본인 민법의 개정은 그만큼 어려운 일이 아닐 수 없다. 이 글을 통해 민법(특히 재산관계)을 어떻게 개정해야 할지, 외국법을 어떻게 받아들여야 할지, 일본의 민법개정 과정을 보며 우리에게 좋은 방법은 무엇인지 생각할 수 있게 되었다면 다행이다. Recently an amendment of civil code passed the Diet in Japan. This amendment spent time of 10 years, and much criticism was raised by its process. An aim of the Ministry of Justice which promoted legislation consequently was a different amendment. It"s Kato of a famous civil law scholar that it was in the van of such criticism. Prof. Kato concerned a civil code amendment while opposing oneself to the Ministry of Justice later while cooperating with the Ministry of Justice at the beginning. There is a purpose in the case that this study reviews this civil code amendment. How to do the change by touching the process of the civil code amendment would be reference. An amendment in this civil code couldn`t achieve the goal the Ministry of Justice intended first. The amendment which couldn"t achieve the first goal is the deserted one no one can meet. Only loss is also the amendment left for the Japanese country. This unfortunate experience has to be reference valuable for the person who will take charge of administration and politics now. That a large scale amendment in a civil code is very difficult work like establishing a civil code. A Japanese civil code amendment didn"t succeed though it spent long time. Everyone would find out that it`s very difficult to revise a civil code. I expect that this study becomes reference in a problem of how whether to revise like the civil code throat should refer to that case`s foreign law.

Pseudomonas aeruginosa as a model microorganism for investigation of chemotactic behaviors in ecosystem

Kato, J.,Kim, H.E.,Takiguchi, N.,Kuroda, A.,Ohtake, H. Society for Bioscience and Bioengineering, Japan ; 2008 Journal of bioscience and bioengineering Vol.106 No.1

Motile bacteria sense changes in the concentration of chemicals in environments and respond in a behavioral manner. This behavioral response is called chemotaxis. Bacterial chemotaxis can be viewed as an important prelude to metabolism, prey-predator relationships, symbiosis, infections, and other ecological interactions in biological communities. Genome analysis reveals that a large number of environmental motile bacteria possess a number of genes involved in chemosensing and chemotatic signal transduction. Pseudomonas aeruginosa has a very complex chemosensory system with more than 20 chemotaxis (che) genes in five distinct clusters and 26 chemoreceptor (methyl-accepting chemotaxis protein [mcp]) genes. Among the 26 MCPs of P. aeruginosa, nine have been identified as MCPs for amino acids, inorganic phosphate, oxygen, ethylene, and volatile chlorinated aliphatic hydrocarbons, whereas 3 MCPs were demonstrated to be involved in biofilm formation and biosynthesis of type IV pilus. Six che genes are essential for chemotactic responses, while genes in Pil-Chp cluster and Wsp cluster are involved in type IV pilus synthesis and twitching motility and biofilm formation, respectively. P. aeruginosa, with its complex chemotaxis system, is a better model microorganism for investigating ecological aspects of chemotaxis in environmental bacteria than Escherichia coli and Salmonella enterica serovar Typhimurium, which possess a relatively simpler chemotaxis system.

Transcriptional Control by A-Factor of Two Trypsin Genes in Streptomyces griseus

Kato, Jun-ya,Chi, Won-Jae,Ohnishi, Yasuo,Hong, Soon-Kwang,Horinouchi, Sueharu American Society for Microbiology 2005 Journal of Bacteriology Vol.187 No.1

<B>ABSTRACT</B><P>AdpA is the key transcriptional activator for a number of genes of various functions in the A-factor regulatory cascade in <I>Streptomyces griseus</I>, forming an AdpA regulon. Trypsin-like activity was detected at a late stage of growth in the wild-type strain but not in an A-factor-deficient mutant. Consistent with these observations, two trypsin genes, <I>sprT</I> and <I>sprU</I>, in <I>S. griseus</I> were found to be members of the AdpA regulon; AdpA activated the transcription of both genes by binding to the operators located at about −50 nucleotide positions with respect to the transcriptional start point. The transcription of <I>sprT</I> and <I>sprU,</I> induced by AdpA, was most active at the onset of sporulation. Most trypsin activity exerted by <I>S. griseus</I> was attributed to SprT, because trypsin activity in an <I>sprT</I>-disrupted mutant was greatly reduced but that in an <I>sprU</I>-disrupted mutant was only slightly reduced. This was consistent with the observation that the amount of the <I>sprT</I> mRNA was much greater than that of the <I>sprU</I> transcript. Disruption of both <I>sprT</I> and <I>sprU</I> (mutant Δ<I>sprTU</I>) reduced trypsin activity to almost zero, indicating that no trypsin genes other than these two were present in <I>S. griseus</I>. Even the double mutant Δ<I>sprTU</I> grew normally and developed aerial hyphae and spores over the same time course as the wild-type strain.</P>

Risk Factors Affecting Cage Retropulsion into the Spinal Canal Following Posterior Lumbar Interbody Fusion: Association with Diffuse Idiopathic Skeletal Hyperostosis

Kato Shinichi,Terada Nobuki,Niwa Osamu,Yamada Mitsuko 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.6

Study Design: This was a retrospective observational study. Purpose: We identify risk factors, including physical and surgical factors, and comorbidities affecting cage retropulsion following posterior lumbar interbody fusion (PLIF). Overview of Literature: Diffuse idiopathic skeletal hyperostosis (DISH) is considered a risk factor for reoperation after PLIF. We evaluated the effect of DISH on cage retropulsion into the spinal canal, which may require surgical revision for severe neurological disorders. Methods: A total of 400 patients (175 men, 225 women) who underwent PLIF were observed for >1 year. Factors investigated included the frequency of cage retropulsion and surgical revision. In addition, physical (age, sex, disease), surgical (fusion and PLIF levels, cage number, grade 2 osteotomy), and comorbid (DISH, existing vertebral fracture) factors were compared between patients with and without cage retropulsion. Factors related to surgical revision during the observation period were also considered. Results: Cage retropulsion occurred in 15 patients and surgical revision was performed in 11. Revisions included the replacement of pedicle screws (PSs) with larger screws in all patients and supplementary implants in 10. Among the patients with cage retropulsion, the average PLIF level was 2.7, with DISH present in nine patients and existing vertebral fractures in six. Factors affecting cage retropulsion were diagnoses of osteoporotic vertebral fracture, multilevel fusion, single-cage insertion, grade 2 osteotomy, presence of DISH, and existing vertebral fracture. Multivariable analysis indicated that retropulsion of a fusion cage occurred significantly more frequently in patients with DISH and multilevel PLIF. Conclusions: DISH and multilevel PLIF were significant risk factors affecting cage retropulsion. Revision surgery for cage retropulsion revealed PS loosening, suggesting that implant replacement was necessary to prevent repeat cage retropulsion after revision.

In Vitro Growth and Maturation of Mammalian Oocytes

Kato. S.,T. Miyano,H. Hirao,K. Miyake 한국동물생명공학회(구 한국동물번식학회) 1996 Reproductive & developmental biology Vol.19 No.4

Analysis of effects of burning in grasslands with quantifying succession stages by life-history traits in Kirigamine, central Japan

Kato, Jun,Kawakami, Mihoko The Ecological Society of Korea 2013 Journal of Ecology and Environment Vol.36 No.1

To quantitatively analyze the effects of burning, we conducted a vegetation survey in the grasslands in Kirigamine, central Japan. We classified each species into stages of succession based on the life-history traits of the species and defined the score of the species in each stand based on the classification. We weighted the scores with a v-value, the product of coverage and height in the quadrat, and summed them to calculate the index of dynamic status. With these indices, we were able to quantitatively compare the stands in the study area and discern minute differences between the stands with different lengths of restoration periods since the disturbance of burning. These indices correlated with the v-value of trees, suggesting that the disturbance of burning seemed to affect the trees in the stand. We then calculated the growth of the tree species Pinus densiflora to evaluate its contribution to the index of dynamic status.