演講公告-日本數學生態學家 Dr. Iwasa
Yuyun
清大許世壁老師邀請了日本一位生態學家，Dr. Iwasa，訪台。Dr. Iwasa是日本著名的生態數學家，他的學生Dr. Satake曾經兩度
參加台日生態交流研討會，應該有些人還有印象。Dr. Iwasa將在清大給兩場演講，另外會在台大再給一場演講。以下是在清大理論中心演講的訊息，等
台大的公告出來後我再通知大家。有興趣的請踴躍參加，也請多多告訴你的朋友同學們。
毓昀
Speaker: Prof. Yoh Iwasa (Dept. of Biology, Kyushu University)
Time: Jan. 06 (Wed.), 2010
Place: NCTS Lecture Room A, 4F, 3rd General Building,
National Tsing Hua University
<< Talk 1 11:00AM - 12:00PM >>
Title: Evolution of Masting-
Synchronized and Intermittent Reproduction of Trees
Abstract:
Trees in mature forests often show synchronized and intermittent
reproduction, named masting. The dynamics of the resource reserves of
individuals demonstrate that, even in a constant environment, trees
may
show a large between-year fluctuation in seed crops, being
synchronized
over the whole forest if the fruit production is limited by the
availability of outcross pollen (pollen coupling). We studied the
conditions for masting to evolve. Assumptions are: the forest is
composed
of a number of sites, each occupied by a canopy tree. After a tree
dies,
the vacant site becomes available for recruitment from seeds. We
found
that the regeneration dynamics of trees are very important for
masting
evolution: masting will never evolve if the vacant sites (gaps)
created in
a year are all filled by individuals from seeds produced in the same
year,
even if seed production is improved in mast years (via enhanced
pollination efficiency and satiating seed predators). This is because
the
intense competition among seeds for acquiring the vacant site cancels
out
the benefit of seed production success. Masting can evolve if
seedlings
can survive over several years waiting for gap openings.
<< Talk 2 3:00PM - 4:00PM >>
Title: Cancer as A Mini-Evolutionary Process
Abstract:
Cancers result from the accumulation of inherited and somatic
mutations in
oncogenes and tumor suppressor genes. Those mutations increase the
net
reproductive rate of cells. Many aspect of carcinogenesis can be
handled
as evolutionary processes.
[1] Chromosomal instability (CIN) is a feature of most human
cancers.
>From the mathematical analysis of situations where inactivation of one or
two tumor suppressor genes is required for tumorigenesis, we conclude
that
CIN is likely to emerge first and then enhance the risk of cancer.
[2] Most epithelial tissues have common architecture -- a tissue is
organized into numerous small compartments, and within each
compartment
includes a few stem cells and numerous differentiated cells. This
design
can slow down delay the onset of cancer.
[3] The ABL tyrosine kinase inhibitor imatinib in chronic myeloid
leukemia
(CML) serves as a model for molecularly targeted therapy of cancer. We
show
that a four-compartment model can explain the kinetics of the
molecular
response to imatinib in a 169-patient data set.
We also calculate the probability of developing imatinib resistance
mutations.
seven
Prof. Iwasa 在台大的TALK 應該是---
Paradox of nutrient removal: coupled socio-economic and ecological
dynamics to control lake water pollution.
時間應該是 1/8 (Friday) 上午11點左右吧!
地點: Room 101, New Mathematics Building, National Taiwan University.
詳情請見 http://math.cts.ntu.edu.tw/ 的微分方程研討會議程內容
看來台大這一場應該就很棒了!
清大那兩場因為剛好同時中研院有另一個SEMINAR
只好忍痛割愛了!
Cheers,
SEVEN
Yuyun
第一場跟我現在做的研究有點關係，是大開花的題目。基本上，最後的結果竟然是：大開花的演化跟小苗存活率有關（有點跟storage effect的預
測背道而馳的感覺，很酷。），不過呢，模型的一些假設還有帶商榷，總之很有趣。
第二場也很棒，是講癌細胞的形成（因為時間不夠，只能講形成的部分，沒辦法提到增生和擴散）。光是前面的原理就讓我獲益良多，後半段的數學模型和結果更
是精彩，錯過的人，唉，可惜可惜。這個部分雖然是用癌細胞當作模型，但本質上還是牽涉了演化，對小族群和大族群（我們的細胞，即使是在同一組織，也分不
同族群喔）的癌化有很清楚的交代。
這兩場演講的PPT已在清大理論中心網站貼出，供大家下載，有興趣的請自取。
Dr. Iwasa雖然是作生物數學的，但是他很注重對系統的明確設定，也就是說，他會把要模擬的主題交代的很清楚，他的演講對學生物的人來說，並沒有
那麼困難。數學部分他只帶出必要的式子，沒有一堆證明，所以難度也不高（當然啦，我們這裡的數學家們就有點意猶未盡啦，總希望多看一點式子，哈哈。）
Dr. Iwasa是個學識很淵博的教授，出過很多著作（超過兩百篇喔），錯過清大演講的人盡量參加台大的部分吧。
以上與大家分享。
毓昀
seven
果然很精彩! 不愧是大師
聽完我覺得生態學家
未來一定有機會拿下諾貝爾經濟學獎!
SEVEN
Yuyun
係。SEVEN，我們應該找個課題好好合作一下！！
毓昀