Limitations and Noise in Optical Metrology

另外，CLEO部份在星期四的晚上有postdeadline papers的報告，這裡面是一些近期內有相當重要的近期研究成果的報告。其中，就有本實驗室最近在Phys. Rev. Lett.上發表的“Full Control of the Carrier-Envelope Phase of Raman Generated Single-Waveforms”，這是由Andy報告，這一篇的重要性在於我們實驗室應用了單一光源、經由倍頻產生了一系列的Raman Sidebands，解決了phase的問題，產生Single-Cycle Pulse, 且能夠完全任意的調節及控制光脈衝中的Carrier-Envelope Phase，這在對於實驗上有重要的向前推進與其它領域的應用。

另外一篇我覺得不錯的成果是JILA 團隊中Jun Ye所研究的成果 “Phase-stabilized, 1.5W mid-infrared frequency comb”。過去在mid-Infrared 範圍內的frequency comb，一直沒有辦法有很好的結果，主要是受限於Ti:sapphire 、Er:fiber laser的限制，所以frequency comb的波長範圍一直只能局限在2um以下，且功率不高。但JILA團隊將波長範圍推至mid-IR 2.8~4.8 um，這剛好能和一般分子的轉動振動光譜(3~12um)能有部份重疊，在科學上能有重要的應用，且其平均功率有最大有1.5W，在應用上也很有幫助。

其它領域的發展也是很快速的，但礙於篇幅，就不其仔細說明我在上列幾個議題內容的重要性。

這一次能夠有這個榮幸參加CLEO這個國際會議，內心感到非常榮幸，雖然之前在實驗時所遇的困難歷歷在現；之前準備報告忙的沒日沒夜的，但我覺得這是值得的，CLEO回來之後，讓我的視野開闊了不少。在過去的幾年裡，就是透過網路、文獻，默默地在實驗室做實驗，有時候其實會搞不清楚自己所做的這些研究，到底對科學上有沒有一點貢獻、價值在何處；有時候會覺得自己是不是隻井底之蛙般地窺看這個世界。但這次參加了CLEO會議之後，和世界各領域的人有了面對面直接的接觸，對自己所做的實驗感到更有信心、心中也產生更大使命感，要繼續在這個領域上耕耘。

最後，我要感謝孔慶昌研究員，及所上、院內在經費上提供的補助，讓我去參加這一次的CLEO會議，開闊了我的視野，見識了當前各領域尖端的研究成果，謝謝!!

二、基因體研究中心 董璐博士後研究學者

會議名稱: RNA 2009: Fourteenth Annual Meeting of the RNA Society

地        點: USA, Wisconsin Madison

會議日期: 98/05/26~98/05/31

First of all, I wish to acknowledge the travel fund from the Genomics Research Center providing the great opportunity allowing me to attend the 14th annual meeting of the RNA Society, which was held at University of Wisconsin (Madison, Wisconsin, United States) from May 26 to May 31, 2009. RNA Society is a multi-discipline society, and the annual meeting is for all scientists whose work is related to RNA. More than 1500 scientists from 23 countries (i.e., Taiwan, China, Japan, Korea, Singapore, India, Australia, United States, Canada, Mexico, Argentina, United Kingdom, France, Germany, Poland, Italy, Switzerland, Spain, Sweden, Portugal, Austria, Denmark and Israel) attended this meeting. The research topics ranged from basic research of splicing mechanisms, RNA turnover, non-coding and regulatory RNAs, all the way to the roles of RNA in disease. Reports of novel findings were organized into 163 oral presentations and 425 poster presentations.

The meeting began with keynote lectures given by two eminent scientists Shiv Grewal (National Cancer Institute) and Robert Darnell (Rockefeller University) about “RNAi-mediated Epigenetic Control of the Genome” and “Decoding protein-RNA regulation with HITS-CLIP maps”, respectively, on the first evening. On the following days, oral presentations of interest to general audience were arranged in the morning then three or four more specialized sessions were held concurrently in the afternoon, and poster sessions were in the evening. In addition to these sessions, workshops such as “Mentoring Graduate Students”, “Non-academic Careers”, and “Scientific Communication” were also designed for scientists of interest. For postdoctoral fellows and graduate students, a “Mentor-Mentee Lunch” was held to discuss important issues, such as “teaching”, “grant writing”, “balance of work life and family life” with senior PIs. Below, I will briefly review sessions that I have attended.

Oral presentations

About 11 oral presentations (10-minute each) were pre-selected on the basis of their significance and timeliness by the organizers and session chairs within each subject area. Roughly half of the presenters were postdoctoral fellows and half graduate students. I rarely found PIs gave the talk, suggesting that graduate students and postdocs were not only encouraged (and supported) to attend international meetings, but also to give talks in front of experts of the field. My work was chosen for an oral presentation few years ago, and that was quite an experience. Also, it never ceased to amaze me that many graduate students, particularly in the top institutions, could achieve substantial amount of work in their graduate tenures. I strongly believe that graduate students should attend this kind of meeting at least once, to face the real world in competitive research. There were, of course, talks that were not particularly exciting, perhaps selected on the basis of the fame of the PIs. As to the session chair, I was most impressed by Kathleen Hall (Washington University, who first gave a crystal clear introduction of the field of RNA structure and folding and pointed out where each talk fit in. Later, she often helped to clarify questions raised from the audience, so the speaker could catch the key point and answer properly. In addition, she managed the time very well with a great sense of humor to avoid unnecessarily delay of her session.

From the platform presentations, one gained a sense what are hot out there. For example, genome-wide approach by deep sequencing of RNA-protein interactions is clearly a powerful approach. And, in the session of coupling of post-transcriptional RNA processing, histone modification emerged as a new territory for exploration. It is probably worth attempting to take advantage the excellent facilities and supports within Academia Sinica to approach some of the same issues in these new lights for charting the unknown water.

Poster presentations

Although it is noteworthy to be selected for an oral presentation, considering gathering the advantage of gaining lots of feedbacks and ideas from a wide audience, a poster presentation may be preferable. In the RNA meeting this year, posters were set up in the morning to let people have chance to glance them before the bustling evening. There were about 140 posters per day, and among them, fewer than 10 are directly related to our work. Another 10 posters would be of general interest to our lab, and the other 10 were probably from labs we acquainted. So, it was possible to talk to every poster presenter I was interested in during the three-hours session. I had a poster entitled “Scores of Transcriptional Perturbations Bypass Sub2p DExD/H-Box Protein: Implications for a Linkage between Transcription and Splicing at the Intron Branch-Site Recognition” on the last day. It was about our finding that several specific mutations of transcription factors, as well as perturbation of transcription elongation, could make an essential splicing factor Sub2p non-essential. Biochemical analyses suggest that the bypass of Sub2p is due to the reduction of association of the Branch-site Binding Protein (BBP) to the transcript. I also found that mutation of a transcription initiation factor altered the recruitment pattern of U1 and U2 snRNPs. My findings therefore indicate a functional linkage between transcription and splicing in budding yeast. There were more than 10 scientists stopped by my poster and gave me quite a few suggestions. Tracy Johnson (University of California, San Diego) and her student Felizza Gunderson suggested me to examine if U4, U5 and U6 snRNP were also impacted by the same mutations of transcription initiation factor I identified and to distinguish the chromatin-immunoprecipitation patterns of two RNA polymerase mutations, which is in progress. Richard Grainger (Edinburgh University) was quite nervous about my finding because I found that deletion of CWC21, which encodes a protein of unknown function, could make Sub2p dispensable, indicating a role of Cwc21p in either transcription or splicing. Cwc21p happens to be the subject Richard is currently working with, and he just gave a talk about his research about Cwc21p the other day.

Cameron Mackereth (Institut Européen de Chimie et Biologie, Bordeaux, France) came to tell me that he worked in the lab that published the structure of mammalian BBP-RNA interaction I adapted in my poster. He was very amazed by my genetic finding in the yeast counter parts. Brian Rymond (University of Kentucky), who just published a paper about Sub2p and BBP not too long ago, also came to see my poster. He told me that he already published the first quarter of my work, and I could only reply that it was a very nice paper. Brian was actually the one who understands most of the detail about my work, though he now turned his attention to telomere regulation by Sub2p and BBP. David Brow (University of Wisconsin-Madison), Martine Collart (University of Geneva), and Raymond O’Keefe (University of Manchester) asked me to walk them through the poster. Jo Ann Wise (Case Western Reserve University) and Manuel Ares, Jr. (University of California, Santa Cruz) swung by and I was too busy to have a chat with them. Graduate students from Eckhard Jankowsky lab (Case Western Reserve University), Melissa Jurica lab (University of California, Santa Cruz), and Anita Hopper lab (Ohio State University) also came to asked for a presentation. At the end of the poster session, I only wished I could have a microphone so I could speak louder.

Workshop: Scientific Communication

At the beginning of this session, we were taught how to write a paper and what the process of a paper from submission to publication is. The guide line is very much similar to what Dr. Tien-Hsien Chang has told us repeatedly: (1) ask an important question, (2) work with smart people, (3) work in a productive environment, (4) make clear and logic approach, (5) integrate writing with research, and (6) turn results into figures. In the second half of the workshop, Tim Nilsen (Case Western Reserve University), the Editor-in Chief of the RNA journal, introduced the review process and behaviors that may antagonize the reviewers and editors. I felt Tim fit nicely with the assigned topic, to which he is a great speaker. Finally, two young editors (both females) from Cell and Nature introduced the policies of their respective journals and sister journals.

Mentor-Mentee Lunch: Balance of Work Life and Family Life

More than 400 graduate students and post-doc members attended this lunch. We were arranged to sit with two mentors and eight mentee per table. The two mentors in my table were Anita Corbett (Emory University) and Nils Walter (University of Michigan). Anita was the first female faculty member in her department when she was recruited by Emory University. I asked Anita when is the best time for female scientist to have kids. Anita gave quite a bit of comparison between herself, who had kids three years after her becoming a PI, and a colleague who had kid in a rather early stage of her career. The bottom line, according to Anita, is that it really does not matter. As long as you know the trick and work hard, female scientists can have kids any time. Anita also shared her experience in how she survived as the only female faculty in her department. Joseph Whipple from Eric Phizicky’s lab (University of Rochester) worried about where he should go for a postdoc. Nils’s wife stays at home taking care of everything, so he was quite lucky. Anita’s husband is an engineer, so it was relatively easier for him to find a job. I was very impressed by what Anita told us: work for as tough (“as in her own words) a guy as you can tolerate for post-doc may actually benefit yourself, because such a tough personality often was able to provide an excellent training environment to fire up one’s competitive edge.

Overall, I feel that attending the RNA meeting really helps me a lot. This is the fourth time I attended the RNA meeting, and I learned different things every time. I really appreciate the support from my mentor Dr. Tien-Hsien Chang and the Genomics Research Center.