# Seminar Report

## Report of iTHEMS colloquium - Tropical Rain Forest

2019-03-01

iTHEMS Colloquium was held on February 21st, inviting Dr. Akiko Satake, Professor of Kyushu University. Her lecture was entitled “Tropical Rain Forest.” In forests, flowering and fruit production are synchronized between different trees with irregular intervals of several years. Dr. Satake integrated long-term data and mathematical modeling, and found the triggers for mass flowering are temperature and drought. In fact, by using her model and the data of temperature and precipitation, she accurately predicted the mass flowering timing. This study will reveal the link between macroscopic (ecosystem) and microscopic (gene regulatory system) phenomena. Because the research topic is interesting and her presentation was easy for non-specialist to understand, we enjoyed active discussion.

Tropical Rain Forest

February 21 at 15:30 - 17:00, 2019

# Hot Topic

## iTHEMS NOW and NEXT

2019-02-28

The in-house gathering entitled iTHEMS NOW and NEXT was held on February 26th. This is the occasion we share current status and future perspectives on our research and organization. In the morning, keynote overview talks were given by Kubota, Fawcett, Kurosawa, Yokokura and Taki. Despite her busy schedule, one of our science advisors, Prof. Kotani managed to attend some talks. Another science advisor Prof. Mori also took time to connect through Skype from Kyoto and gave us some important advice. The afternoon session started with the panel discussion facilitated by Warren, and paneled by Chacha, Fawcett, Furusawa, Miyazaki and Y. Inoue. Both at the morning talks and the afternoon discussion, candid opinions were enthusiastically exchanged. After the panel discussion, three presentations on inter-organizational cooperation by Hatsuda, Nagataki, and Prof. Uchiyama from Rikkyo University.

Everybody in attendance seemed happy to have the opportunity to express her/his opinion on iTHEMS organization. If you could not attend, you can still click the link shown below for your input.

# Upcoming Events

## Math Lecture

### Theory of Operator Algebras (8th)

March 5 at 14:00 - 15:00, 2019

Dr. Yosuke Kubota (Research Scientist, iTHEMS)

Title: An introduction to operator algebras

Abstract: Operators are linear maps from a (usually an infinite dimensional) linear space (most frequently the Hilbert space) to itself, which is like matrices of infinite degree. Operators form an algebra by obvious addition and multiplication. Operators appear in most of the fields in mathematics, in algebra, in geometry, in analysis, ... Some of the key words at the beginning of these lectures are "spectral theory" "operator algebras" "Tomita-Takesaki theory". These lectures are for non-professional people.

Venue: Seminar Room #160, 1F Main Research Building, RIKEN

Event Official Language: Japanese

## Math Lecture

### Theory of Operator Algebras (9th)

March 5 at 15:30 - 16:30, 2019

Dr. Yosuke Kubota (Research Scientist, iTHEMS)

Title: An introduction to operator algebras

Abstract: Operators are linear maps from a (usually an infinite dimensional) linear space (most frequently the Hilbert space) to itself, which is like matrices of infinite degree. Operators form an algebra by obvious addition and multiplication. Operators appear in most of the fields in mathematics, in algebra, in geometry, in analysis, ... Some of the key words at the beginning of these lectures are "spectral theory" "operator algebras" "Tomita-Takesaki theory". These lectures are for non-professional people.

Venue: Seminar Room #160, 1F Main Research Building, RIKEN

Event Official Language: Japanese

## Workshop

### Workshop of Nuclear-Astrophysics by UKAKUREN/Japan Forum of Nuclear Astrophysics (JaFNA): Nuclear data & Heavy Element Nucleosynthesis

March 6 - 8, 2019

We are pleased to announce that we will have a meeting on Nuclear-Astrophysics at Hokkaido Univ. Especially this time we will focus on the impact of nuclear data & nucleosynthesis of heavy elements. Gravitational wave is another keyword.

This workshop is held by UKAKUREN (JaFNA), together with Nuclear Reaction Data Centre, Hokkaido University (JCPRG). This workshop is supported by iTHEMS, CNS, RCNP, NAOJ, KEK, and WNSC.

You are welcomed to join us. For registration, please fill in the attached form (in Japanese) and send it to: sec-ukakuren18@kek.jp by 30th November 2018.

We are looking forward to seeing you at Hokkaido U.

Organizers

T. Kajino (Chair), T. Kawabata (Osaka), H. Utsunomiya (Konan), S. Nishimura (RIKEN), H. Yamaguchi (CNS), T.Hayakawa (QST), T.Motobayashi (RIKEN),

K.Terada(Osaka), S.Nagataki(RIKEN), S.Chiba(TIT), T.Tamagawa(RIKEN), W.Aoki(NAOJ), S.Wanajo(AEI), S.Kubono(RIKEN), T.Shima(RCNP)

Venue: Hokkaido University Conference Hall

Event Official Language: Japanese

## Math Lecture

### Introduction to Public-Key Cryptography (9th)

March 6 at 13:30 - 15:00, 2019

Dr. Eren Mehmet Kıral (Visiting Scientist, iTHEMS / Visiting Scientist, Faculty of Science and Technology, Sophia University)

Venue: Seminar Room #160, 1F Main Research Building, RIKEN

Event Official Language: English

## Colloquium

### ZetaValue2019-iTHEMS Special Mathematics Colloquium

March 21 at 14:00 - 17:30, 2019

Prof. Kohji Matsumoto (Nagoya University)

Prof. Jörn Steuding (University of Würzburg, Germany)

Venue: Okochi Hall, 1F Laser Science Laboratory, RIKEN

Event Official Language: English

## Workshop

### Value distribution of zeta and L-functions and related topics

March 22 - 27, 2019

March 22–26, 2019

Main Conference (invited talks, posters and a limited number of short contributed talks)

Welcome Reception: March 22, 2019 (18:00~20:00)

Conference Dinner: March 25, 2019 (18:30~21:00)

March 27, 2019 (9:30~17:00)

One-day Workshop (a series of short contributed talks by young researchers to facilitate active discussions)

ORGANIZING COMMITTEE

Ade Irma Suriajaya (RIKEN)

Yoshinosuke Hirakawa (Keio University)

Masataka Ono (Kyushu University)

Shin-ichiro Seki (Tohoku University)

Keiju Sono (Ehime University)

Shingo Sugiyama (Nihon University)

Yuta Suzuki (Nagoya University)

ADVISORY COMMITTEE

Tetsuo Hatsuda (RIKEN iTHEMS)

Kenichi Bannai (Keio University, RIKEN AIP Center)

Venue: Okochi Hall, 1F Laser Science Laboratory, RIKEN / Large Meeting Room, 2F Welfare and Conference Building (Cafeteria), RIKEN

Event Official Language: English

## Lecture

### AI Smart Robot Network

March 22 at 15:00 - 17:00, 2019

Prof. Yoshihiro Ohta (Arithmer Inc. / The University of Tokyo)

Venue: Large Meeting Room, 2F Welfare and Conference Building (Cafeteria), RIKEN

Broadcast: R311, Computational Science Research Building, R-CCS, Kobe Campus, RIKEN

Event Official Language: Japanese

## Workshop

### iTHEMS-AIMR Joint Workshop "Medicine meets Mathematics"

March 29 at 10:00 - 17:00, 2019

Speakers:

Takuya Ueda (Tohoku Univ. Hospital)

Noriaki Ogawa (RIKEN iTHEMS)

Takayuki Sakajo (Math. Dep., Kyoto Univ.)

Yoshiki Sugitani (AIMR, Tohoku Univ.)

Jun Seita (RIKEN MIH)

Tetsuro Sekine (Nippon Medical School Hospital)

Masato Taki (RIKEN iTHEMS)

Kenji Takizawa (Faculty of Sci. and Eng., Waseda U.)

Hosted by SUURI-COOL Sendai（iTHEMS-AIMR Mathematical Science Cooperative Lab.）

Co-hosted by iTHEMS, AIMR

Sponsored by CREST "New Challenges for Mathematical Modeling in Clinical Medicine"

Organizers: Hiroshi Suito (AIMR), Tetsuo Hatsuda (iTHEMS)

Venue: 3rd floor Lecture Theater, Katahira Campus, Tohoku University

Event Official Language: Japanese

## School

### g-RIPS Sendai 2019

June 17 - August 9, 2019

GRIPS (Graduate-level Research in Industrial Projects for Students)-Sendai program was held last summer (June 18 - Aug. 10, 2018) with the support of iTHEMS as well as other institutions and companies. Two industrial projects were launched under the suggestion of TOYOTA and NEC, and two teams composed of US and Japanese students have worked intensively to find solutions of these problems. See for the details of the GRIPS program and the summary of activities at GRIPS-Sendai 2018.

This year, GRIPS-Sendai program will be held from June 17 through Aug. 9, 2019 with a larger scale under the support of iTHEMS. Stay tuned for further information.

Event Official Language: English

# Person of the Week

## Self-introduction: Yuki Koyanagi

2019-02-28

Hi everyone. My name is Yuki Koyanagi and I am a visiting student at iTHEMS. My research interest is the study of protein structures, specifically how we can predict local structures of a protein from its sequence of amino acid residues. Knowing the structure of protein is important, because we know that a protein's function is highly dependent on its structure. A protein is made up of lots of amino acids connected like a chain, which then folds itself to a three-dimensional structure. One of the important factors that determine the folding is hydrogen bonds, that form at different places along the chain. I am looking into how we can predict the structure around each hydrogen bond. Another related question is finding out how many different hydrogen bond structures are possible for a given sequence of amino acids.

I am a mathematician and work at a mathematics research centre, the interdisciplinary environment at iTHEMS is something new to me. I am very excited about the opportunity of meeting people from different fields with different backgrounds.

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