2015年5月30日 星期六

Scientists just brought back memories that mice had 'forgotten'


1987年,MIT免疫學教授,出身日本的利根川進
(Susumu Tonegawa)因發現漿細胞能產生多種抗體之機轉,榮獲諾貝爾生理(醫學)奬。其後他轉進最神秘,人類了解最少的腦科學,希望能得第二個諾貝爾獎。2009起,他回日本理研Riken擔任腦科學研究所所長,研究人類的「記憶」與「失憶」。他是另一種天才研究者的典型。
如果「失憶」有一天真的可以reactivate 或 recall 喚回。那真是老年人的一大福音,那麼利根川先生真的有可能破紀錄得到兩次諾貝爾醫學獎。

Researchers have found that memories that have been 'lost' as a result of amnesia can be recalled by activating brain cells with light. They reactivated memories that could not otherwise be retrieved, using a technology known...
SCIENCEDAILY.COM


Scientists say they've restored lost memories in mice. Read more:u.afp.com/ZkCd

2015年5月24日 星期日

a paper describing a technology that cocaine and heroin could be produced locally

If cocaine and heroin could be produced locally, the cartels that now smuggle them might find themselves out of business. Astute drug barons will therefore be reading their copies of Nature Chemical Biology with particular interest—for the current edition of the journal contains a paper describing a technology that could completely disrupt their business http://econ.st/1ekwAYS

SHORTENING an industry’s supply chain is bound to affect the activities of its suppliers. That is as true of the recreational-drugs business as it is of any other....
ECON.ST

2015年5月22日 星期五

「台灣光子源」

預算被刪 全球最亮「台灣光子源」面臨斷電



台灣光子源發射出的亮光,是太陽光的百萬倍。(資料照,記者湯佳玲攝)
2015-05-22  07:48
〔即時新聞/綜合報導〕台灣有史以來最大的科學設施「台灣光子源」,去年底成功發出第一道光芒,即將點亮全世界最亮光源,這道光的亮度是太陽光亮的百萬倍,立刻吸引國際科學界重視,榮登《科學》(Science)等多本國際知名期刊封面,5月份更獲「自然」期刊集團發行的「自然光子學」專文報導,「台灣之光」升級為「世界之光」。但現在預算被刪減,面臨斷電的危機。
國家同步輻射中心主任果尚志表示,台灣光子源是台灣史上規模最大的科學實驗,是一盞「科學神燈」。台灣光子源是透過同步加速器射出的光源為一連續波段的電磁波,涵蓋紅外光、可見光、紫外光、X光等波段,是一種以電子高速繞行軌道的方式,來產生高亮度的光束。
《聯合報》報導,光子源總計畫主持人、中研院院士陳建德表示,2004年他發願挑戰台灣自建加速器,期間歷經政黨輪替、金融海嘯和通膨難關,都挺過順利完工,如今卻面臨預算被刪減、明年運轉預算短缺1億多元,不僅難以建置光束線實驗站,也付不出後半年的運轉電費。陳建德感嘆,現在光子源好不容易被國際看見了,「但我們是否能再次感到驕傲?」
「我們一輩子就等這個機會讓台灣閃耀。」科技部同步輻射中心主任果尚志難過地說,「你不自己點火,沒人會替你發亮。」科技部次長林一平說,已盡力奔走替光子源挪出1億元預算,但各單位都缺錢,實在無法再挪出1億元,希望同步輻射中心共體時艱。
鳥瞰位在國家同步輻射中心的台灣光子源加速器(大環),與舊有的小型加速器(小環)。 (資料照,國家同步輻射中心提供)
台灣光子源團隊的7位主持人齊聚一堂,試車出光後終展笑顏。由左而右分別是計畫總主持人陳建德、共同主持人羅國輝、各分項主持人王昭平、許國棟、郭錦城、王兆恩、陳俊榮。(資料照,記者湯佳玲攝)

2015年5月21日 星期四

Fourier Transformation 簡說

Fourier Transformation 簡說
http://blog.xuite.net/lapuda.chen/PaulBlog/221866406

2015年5月20日 星期三

戴明博士的小故事;公制公約、『世界計量日』

戴明博士的小故事;公制公約、『世界計量日』
http://demingcircle.blogspot.tw/2010/11/blog-post.html

Changing the size of vaccine vials can significantly decrease the cost of vaccine distribution

vial 是裝疫苗的小玻璃管。

How Computational Modeling Can Improve Health: Vial size changes can decrease the cost of vaccine distribution: http://cmu.li/NbBox

Changing the size of vaccine vials can significantly decrease the cost of vaccine distribution, helping to leverage limited funding in low-income...
CMU.LI|由 CARNEGIE MELLON UNIVERSITY 上傳

2015年5月18日 星期一

Dr. Alexander Rich 1924~2015















The Greatest Generation of Scientists
By JOE NOCERA May 19, 2015

專欄作者
亞歷山大·里奇和那個時代偉大的科學家
喬·諾切拉2015年05月19日


A great man died late last month, one of the last of the pioneering biologists who essentially created the modern science of molecular biology. His name was Alexander Rich; he was 90 years old; and he had spent the past 57 years as a professor ​​at the Massachusetts Institute of Technology, where he was still going to work right up until the last two months of his life.


上個月,一個偉大的人物去世了。他名叫亞歷​​山大·里奇(Alexander Rich),是當世僅存的幾位締造了現代分子生物科學的生物學先驅之一。他享年90歲,過去57年裡一直是麻省理工學院(Massachusetts Institute of Technology)教授,直到去世前兩個月,他還在繼續工作。


In her obituary of Rich in The Times last week , Denise Gellene recounted some of his scientific achievements: In 1973, some 20 years after James Watson and Francis Crick worked out the structure of DNA — theoretically at least — Rich proved them right, using “ X-rays to produce a distinct image of the famous double helix.” He then went on to make important discoveries about the structure of ribonucleic acid, or RNA, and the way RNA translated genetic information in DNA. His work on RNA and DNA is one of the foundations of biotechnology and the biotech industry.


《紐約時報》上周刊登的訃告中,作者德妮絲·傑林(Denise Gellene)講述了里奇生前取得的科學成就:1973年,在詹姆斯·沃森(James Watson)和弗朗西斯·克里克(Francis Crick)(至少在理論上)得出DNA的結構20幾年之後,里奇證實他們的論斷是正確的,使用“X射線產生出了著名的雙螺旋結構的清晰圖像”。之後,他又繼續發現了核糖核酸(RNA)的結構,以及RNA將遺傳信息翻譯到DNA當中的方式,這些發現都十分重要。他在RNA和DNA方面開展的工作是生物技術及生物技術產業的一個基石。


Rich was a scientist with a wide-ranging curiosity. In a video that was put together when he won an important award in 2008, Rich talked about “the excitement associated with a discovery. You see something new,” he said. “When somebody else makes a discovery and I read about it, I get that same boost of awe and wonder about nature.”


里奇是一個興趣廣泛的科學家。在2008年獲得一個重要獎項後製作的視頻中,里奇談道了“得出發現時的興奮。你看到了新東西,”他說。“我讀到別人的發現時,也會促使我對大自然產生相同的敬畏和驚奇。”



In his lifetime, he met Albert Einstein, worked under Linus Pauling, and knew everyone from Crick and Watson to the great physicists Leo Szilard and Richard Feynman. Rich co-founded several companies. He mentored scientists who would go on to make their own important discoveries. He helped establish Israel's Weizmann Institute of Science, which is today one of that country's leading scientific institutions. He was a member of the Pugwash Conferences on Science and World Affairs , whose founding mission was to eliminate nuclear weapons. “Alex lived a rich and important life,” wrote Phillip Sharp , a scientist at MIT who was close to him. That he did.


在里奇的一生中,遇到過阿爾伯特·愛因斯坦(Albert Einstein),曾在萊納斯·鮑林(Linus Pauling)手下工作,認識克里克、沃森以及利奧·西拉德(Leo Szilard)和理查德·費曼(Richard Feynman)等等偉大的物理學家。里奇參與創立了數家公司,他指導過的科學家接下來又相繼做出了重要的發現。他幫助建立了以色列的魏茨曼科學研究學院(Weizmann Institute of Science),如今它成了該國領先的科研機構之一。他是帕格沃什科學和世界事務會議( Pugwash Conferences on Science and World Affairs)的成員,這個組織創始使命是銷毀核武器。與里奇關係緊密的麻省理工科學家菲利普·夏普( Phillip Sharp )寫道,“亞歷山大度過了豐富而重要的一生。”的確如此。


But as I l​​ooked into his life this week, three things struck me, all of which could be said not only of Rich, but of most members of that remarkable generation.


然而本週我回顧他的一生時,有三件事讓我印象深刻。這三件事不僅體現在里奇身上,而且在那一代的大多數傑出人物身上也都有體現。


The first was how maddeningly difficult — and painstaking — it was to create the building blocks of molecular biology. In the early 1950s, recalled Jack Strominger , a scientist at Harvard who was Rich's roommate in college, the federal government did not hand out grants to scientists the way it does today; so just getting the money to do science was hard.


首先,打下分子生物學的基礎,異常艱難,而且需要付出辛勤的努力。曾是里奇大學室友的哈佛大學(Harvard)科學家傑克·施特羅明格(Jack Strominger)回憶道,在上世紀50年代初期,聯邦政府並不像今天這樣向科學家發放撥款,所以單單是拿到科研經費就相當困難。


“You walk into a lab today and you see the rows of equipment,” Strominger said. Equipment was much harder to come by, and not as precise. “As late as the 1980s,” he says, “X-ray crystallography was a difficult field. Now a young person can do it quickly.” It took many years — of trial and error — before Rich proved, through X-ray crystallography, that the Crick and Watson double helix structure was correct. “Persistence is luck,” Rich was known to say. That certainly was true of his generation of biologists.


“你今天走進實驗室裡,能看到成排的儀器,”施特羅明格說。但當時得到實驗設備要難得多,而且也沒那麼精密。他說,“遲至1980年代,X射線晶體學都還是一個很難的領域,現在一個年輕人就可以很快做好。”里奇經過了很多年——很多年的試錯——才終於通過X射線晶體學的手段,證實了克里克和沃森研究發現的雙螺旋結構是正確的。“堅持不懈就是幸運,”里奇曾這樣說。這對於他那一代生物學家來說,無疑是成立的。

http://en.wikipedia.org/wiki/RNA_Tie_Club
The second insight was how collaborative the scientists were. One good example was something called the RNA Tie Club , of which Rich was a member. Founded by the physicist George Gamow, it was a collaborative effort to figure out the structure of RNA. (Each member was given a tie with a green-and-yellow RNA helix; hence the name of the group.) Although the members met infrequently, they circulated papers among each other and talked freely about their ideas, not fearing that their ideas would be stolen or misused.


第二個洞見在於,當時的科學家多麼樂於協作。一個例子是被稱為“RNA領帶俱樂部”( RNA Tie Club )的組織,里奇就是其中的成員。由物理學家喬治·伽莫夫(George Gamow)建立的這個組織,目的是通過協作研究出RNA的結構。(每一位成員都得到了一條印有黃綠相間的RNA螺旋圖案的領帶,俱樂部因此而得名。)儘管成員間聚會並不頻繁,但是他們相互之間會傳閱論文,自由地交流觀點,不用擔心自己的觀點被人偷走 ​​或誤用。


That kind of collaboration is something that has been largely lost in the scientific world. “Everything is so much more competitive now,” says Strominger. Scientists today are more likely to look for niches they can dominate. They compete to get their discoveries published ahead of rivals. Or to start a biotech company and make millions. “It would be pretty hard to capture the flavor of that period again,” says Strominger.


這種程度的合作,如今在科學界基本上已經不復存在。“所有領域的競爭現在都更激烈了,”施特羅明格說。今天的科學家更傾向於找一些能夠主導的細分領域,他們爭先恐後地要搶在對手前面發表論文介紹自己的發現,要么就是搶著開一家生物科技公司,賺到數百萬美元。施特羅明格說,“很難再找到那個時代的氣息了。”


Finally, one gets the sense — and this is especially true of Rich — that they didn't get into science to get rich or become famous. They loved science for its own sake. Rich would call other scientists, often in the evening, just to talk shop. “I never saw Alex bad-mouth another scientist, even when he had reason to,” said Robert Gallo , the director of the Institute of Human Virology at the University of Maryland School of Medicine. “I don't know anybody who was more interested in science for its own sake than that man. He lived it and loved it.”


最後,我們還能感覺到,他們投身科學事業不是為了發財或成名,這一點在里奇身上尤為突出。他們熱愛科學只是為了科學本身。里奇會給其他科學家打電話,常常是在傍晚,只是談工作。“我從來沒有見過亞歷山大說其他科學家的壞話,即使他有理由那樣做時也不會,”馬里蘭大學醫學院人類病毒學研究所主任羅伯特·加洛( Robert Gallo )這樣說。“他對科學感興趣是出於科學本身,我不知道誰在這一點上還能超過他。科學就是他的生活,他熱愛科學。”


In the course of talking to Strominger, I discovered that, at 89, he is also still going to work every day. ​​Why didn't scientists like him and Rich retire? I asked.


在與施特羅明格交談的過程中,我發現他在89歲高齡仍然每天去工作。我問道,為什麼像他和里奇這樣的科學家,不退休呢?


“Why should we?” he replied. “It's too much fun.”


“為什麼要退休?”他回答道。“工作太有趣了。”


Copyright © 2013 The New York Times Company. All rights reserved.

翻譯:王童鶴



Alexander Rich Dies at 90; Confirmed DNA’s Double Helix


James Watson and Francis Crickworked out the spiral structure of DNA in 1953, but they were not proved right until Dr. Alexander Rich used X-rays to produce a distinct image of the famous double helix in 1973. After he saw it, Dr. Watson phoned Dr. Rich to thank him; it was the first good night’s sleep Dr. Watson had enjoyed in 20 years.

For nearly six decades, Dr. Rich, who died at 90 on April 27 in Boston, doggedly investigated DNA and RNA, the fundamental molecules of life.

He helped puzzle out the structure of collagen, a protein that is abundant in ligaments and skin, and he discovered that DNA can exist in an odd zigzag form, which he called Z-DNA.

His work provided insights into how cells manufacture proteins, and laid the groundwork for techniques that scientists use to identify, manipulate and replace bits of genetic material. Diagnostics for H.I.V. infection and tests for genes that cause breast cancer are among the technologies built on his discoveries.

“I can think of no one else who has made as many major contributions to all facets of modern molecular biology,” said Dr. Robert C. Gallo, a co-discoverer of the AIDS virus and the director of the Institute of Human Virology at the University of Maryland School of Medicine.

In 1995, President Bill Clinton awarded Dr. Rich the National Medal of Science, the highest scientific honor bestowed by the federal government.

His death was announced by the Massachusetts Institute of Technology, where he had been a professor since 1958.

Alexander Rich was born on Nov. 15, 1924, in Hartford, the son of immigrants from Russia who never finished high school. He grew up in Springfield, Mass. His father, Max, ran a dry cleaning business that faltered during the Depression, causing the family to move several times. His mother, the former Bella Shub, died when he was around 14; he went to live with an aunt and uncle.

Dr. Rich attended a technical high school, where his education largely focused on how to operate machine lathes and other industrial equipment, preparing him for a manufacturing job. But an English teacher, noticing his curiosity and drive — Dr. Rich was working the graveyard shift at a military firearms factory in Springfield — encouraged him to join an after-school science club and later urged him to apply to Harvard. It awarded him a scholarship, and he enrolled in 1942.

He interrupted his studies when, during World War II, he enlisted in a Navy officer training program, which sent him to a hospital on a submarine base and then to Syracuse University Medical School. He was discharged in 1946 and, after returning to Harvard, received a bachelor’s degree in biochemical sciences in 1947 and a medical degree in 1949.

Dr. Rich moved to the California Institute of Technology as a research fellow in the lab of Linus Pauling, who would receive the Nobel Prize in Chemistry in 1954 for his work on chemical bonds. Dr. Pauling was locked in the race to figure out the structure of DNA, a competition he would lose.

For nearly six decades, Dr. Rich, who died at 90 on April 27 in Boston, doggedly investigated DNA and RNA, the fundamental molecules of life.

He helped puzzle out the structure of collagen膠原蛋白, a protein that is abundant in ligaments韌帶 and skin, and he discovered that DNA can exist in an odd zigzag form, which he called Z-DNA.

His work provided insights into how cells manufacture proteins, and laid the groundwork for techniques that scientists use to identify, manipulate and replace bits of genetic material. Diagnostics for H.I.V. infection and tests for genes that cause breast cancer are among the technologies built on his discoveries.

“I can think of no one else who has made as many major contributions to all facets of modern molecular biology,” said Dr. Robert C. Gallo, a co-discoverer of the AIDS virus and the director of the Institute of Human Virology at the University of Maryland School of Medicine.

In 1995, President Bill Clinton awarded Dr. Rich the National Medal of Science, the highest scientific honor bestowed by the federal government.

His death was announced by the Massachusetts Institute of Technology, where he had been a professor since 1958.

Alexander Rich was born on Nov. 15, 1924, in Hartford, the son of immigrants from Russia who never finished high school. He grew up in Springfield, Mass. His father, Max, ran a dry cleaning business that faltered during the Depression, causing the family to move several times. His mother, the former Bella Shub, died when he was around 14; he went to live with an aunt and uncle.

Dr. Rich attended a technical high school, where his education largely focused on how to operate machine lathes and other industrial equipment, preparing him for a manufacturing job. But an English teacher, noticing his curiosity and drive — Dr. Rich was working the graveyard shift at a military firearms factory in Springfield — encouraged him to join an after-school science club and later urged him to apply to Harvard. It awarded him a scholarship, and he enrolled in 1942.

He interrupted his studies when, during World War II, he enlisted in a Navy officer training program, which sent him to a hospital on a submarine base and then to Syracuse University Medical School. He was discharged in 1946 and, after returning to Harvard, received a bachelor’s degree in biochemical sciences in 1947 and a medical degree in 1949.

Dr. Rich moved to the California Institute of Technology as a research fellow in the lab of Linus Pauling, who would receive the Nobel Prize in Chemistry in 1954 for his work on chemical bonds. Dr. Pauling was locked in the race to figure out the structure of DNA, a competition he would lose.


In his search for clues about the configuration of DNA, Dr. Rich turned to an analytical tool called X-ray crystallography, which uses X-ray beams to determine the location of atoms in a molecule. Dr. Pauling had used the method in his groundbreaking work on chemical bonds.

But the equipment at Caltech was not well suited to analyzing long, fibrous molecules like DNA, and, as Dr. Rich soon learned, he was late to the race. Five months after Dr. Rich started his work, Dr. Watson and Dr. Crick announced that they had completed their cardboard model of DNA. Although theoretical, the model was accepted because it fit with everything that was known about DNA at the time.

Dr. Rich shifted his focus to the structure of RNA, the next big challenge in molecular biology. Scientists at the time understood that RNA translated genetic information in DNA into codes for proteins, but how this occurred was still a mystery.

Dr. Rich worked for a time with Dr. Watson, who briefly moved to Caltech after his DNA discovery, but the pair made little headway. After a while, Dr. Rich’s confidence wavered. “I had serious doubts whether I could, in fact, make important discoveries,” he wrote in a 2004 accountof his research career.

In 1954 he moved to the newly formed National Institute of Mental Health as section chief in physical chemistry and continued to work on the structure of RNA. Realizing he needed better equipment for an experiment, he traveled to England to work with Dr. Crick and use the more powerful X-ray machine at the University of Cambridge.

Not long after Dr. Rich’s arrival, however, the scientists realized that they shared a curiosity about the structure of collagen and shifted their research. Using everything known about collagen at the time, they built a six-foot-tall wire model of the molecule and painstakingly calculated the approximate location of its atoms. At the end of the monthslong project, Dr. Rich felt his confidence return.

“I began to develop some self-assurance in my ability to carry out research and make discoveries,” he wrote.

More discoveries soon followed.

In 1956 he showed that two strands of RNA could spontaneously join together to form a double helix, and in 1960, two years after he moved to M.I.T., he showed that strands of RNA and DNA could join to form a double helix. These discoveries led to a method for comparing similarities between pools of DNA, laying the groundwork for diagnostic tests and many of the scientific tools used to detect genes in tissues.

After these discoveries, Dr. Rich took advantage of improvements in X-ray crystallography to produce the first image of the RNA double helix at atomic resolution. Because RNA and DNA are complementary molecules, the 1973 image confirmed the structure of DNA. “The uncertainty about the organization of the double helix was resolved,” Dr. Rich wrote.

A year later, he used X-ray analysis to solve the three-dimensional structure of one of three forms of RNA, all of which are critical to the manufacture of proteins.

Toward the end of his life he worked to unravel the mystery of Z-DNA, which, in addition to having a zigzag backbone, spirals to the left instead of to the right. Although its function is unknown, Dr. Rich and others found hints that Z-DNA has a role in some autoimmune diseases and certain viral infections, like small pox.

Dr. Rich was a member of the National Academy of Sciences, the French Academy of Sciences, the Russian Academy of Sciences and the Pontifical Academy of Sciences. He co-founded several biotechnology companies, including Repligen in 1981 and Alkermes in 1987.

Dr. Rich’s survivors include his wife of 62 years, the former Jane King; two sons, Josiah and Benjamin; two daughters, Jessica Rich Sturley and Rebecca Rich; and seven grandchildren.

Dr. Rich liked to recall the time he presented his collagen research at a scientific conference and ran into his old mentor. Dr. Pauling, he said, remarked that Dr. Rich had spent a long time in his lab without accomplishing much, but that he must have learned quite a bit.

“I felt that it was probably a fair assessment,” Dr. Rich said.

2015年5月17日 星期日

perovskite 鈣鈦礦


Many firms, both small and large, see promise in perovskites. These are compounds that share a crystal structure and are named, collectively, after the mineral that was the first substance found to have this structure. Often, they are semiconductors. This means that, like the most famous semiconductor of all, silicon, they can be used in solar cells http://econ.st/1JLrtuF

ON THE desk of Chris Case, chief technology officer of Oxford Photovoltaics, there sits a small but heavy vial filled with a canary-yellow liquid. “That’s enough...
ECON.ST



鈣鈦礦是指一類陶瓷氧化物,其分子通式為ABO3;此類氧化物最早被發現者,是存在於鈣鈦礦石中的鈦酸鈣(CaTiO3)化合物,因此而得名。由於此類化合物結構上有許多特性,在凝聚體物理學方面應用及研究甚廣,所以物理學家與化學家常以其分子公式中各化合物的比例(1:1:3)來簡稱之,因此又名「113結構」。

2015年5月14日 星期四

電磁軌砲(英語:Railgun)

Speed kills, cheaply. America’s navy is trading explosives for electricity and arming its ships with railguns. A railgun can hurl shells at seven times the speed of sound—three times the muzzle velocity of a conventional naval gun. The fiery plume, visible in the video, is not the result of propellant exploding but of the air itself being ionised by the electric current in the barrel. The first firing tests on board ship will take place next year. If they're succesful, the centuries-long monopoly of gunpowder will have come to an end http://econ.st/1HfUs9y

電磁軌砲英語Railgun),是一種將電能轉換成被投射物的動能的加速裝置,屬於電磁砲其中一種。
電磁軌砲是利用電磁產生的洛倫茲力(Lorentz force)來投射物品,所以被投射物的其中一部份必須要是導體。當電流通過軌道時產生磁場。磁場穿過被投射物並與其內電流形成約90°角,這會在被投射物上產生推力並以高速推出被投射物。另還有以線圈或電熱方式發射。
鑑於電磁磁軌砲沒有推進燃料,所以嚴格來說,電磁磁軌砲是冷兵器的一種。

理論和建造[編輯]

磁軌砲的運作概要圖。
當一個帶電流的電線在一個磁場中,會受到與電流和磁場垂直的洛倫茲力。當充電時,軌道的電流先會在電線周圍產生磁場(右圖藍色),被拋射物上有一個可以自由移動的電線(右圖橘色部分)。當被拋射物的電線有電流時,會和磁場產生洛倫茲力(右圖綠色部分);這推力作用在被拋射物的電線上,會使得被拋射物沿著軌道射出。
除了作為武器外還把其大型化用來發射太空船的設計,即質量投射器,又分為在地上或太空基地把太空船射出的電磁彈射器類型和直接裝在太空船上以反作用力向後拋出推進劑的火箭類型方案。
2012年2月28日,美國宣布成功試射第一部由軍工企業製造的具有超遠射程的電磁軌道炮原型。美國海軍表示電磁軌道炮原型已試射6次,炮彈時速高達8000公里。該電磁軌道炮原型由英國航太系統公司(BAE Systems)製造,1月30日運抵位於維吉尼亞州達格倫海軍水面武器中心達格倫分部(Naval Surface Warfare Center Dahlgren Division, NSWCDD)。按照設計理論,電磁炮炮彈最高速度將達每小時9010公里,是音速的7倍以上[1]

應用[編輯]

  • 美國海軍亞里·伯克級驅逐艦的後繼實驗艦朱瓦特號(USS Zumwalt DDG-1000),2013年10月28日晚間在緬因州下水,從巴斯造船廠乾船塢移到肯納貝克河,將會在2014年春完成最後階段建造工程,並計畫在2015年移交給美國海軍。這隻配備電磁軌炮的驅逐艦,也是美國海軍歷來最大型隱形驅逐艦。

Quest for a Superbee超級蜜蜂。

As bees labor to make honey, they are unaware that their greatest role in nature is to distribute pollen. But this vital process has been threatened for decades by mites 蟎蟲 and diseases, causing experts to wonder: is it possible to engineer a more resilient bee?

Can the world's most important pollinators be saved? How scientists and breeders are trying to create a hardier honeybee.
NGM.NATIONALGEOGRAPHIC.COM|由 CHARLES C. MANN 上傳

如何從恐龍的口鼻部演化到鳥喙 How Bird Beaks Got Their Start As Dinosaur Snouts

如何從恐龍的口鼻部演化到鳥喙......
How Bird Beaks Got Their Start As Dinosaur Snouts
MAY 12, 2015 7:32 PM ET

NELL GREENFIELDBOYCE

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The skull of a chicken embryo (left) has a recognizable beak. But when scientists block the expression of two particular genes, the embryo develops a rounded "snout" (center) that looks something like an alligator's skull (right).Bhart-Anjan S. Bhullar

Scientists say they have reversed a bit of bird evolution in the lab and re-created a dinosaurlike snout in developing chickens.

"In this work, we can clearly see a comeback of the characteristics which we see in some of the first birds," says Arhat Abzhanov, an evolutionary biologist at Harvard University.

The ancestors of birds are a group of dinosaurs that includes the famous velociraptor, Abzhanov says. This group of meat-eaters had long snouts, small brains and eyes, and lots of teeth. Somehow they transformed into birds, which have none of those things.

Bhart-Anjan Bhullar, another member of the research team at Yale University, says the goal is to understand exactly how birds became birds. "What's the deep history of birdiness?" wonders Bhullar. "How did the different parts of their body plan form?"
i
An artist's rendition of anchiornis, a non-avian dinosaur(top), and a modern tinamou, with key bones highlighted in each face.John Conway一個藝術家的演繹,anchiornis,一個非鳥類恐龍(頂部),以及一個現代化的tinamou,與主要的骨頭中的每個face.   John康威強調

In particular, he and his colleagues are interested in birds' distinctive beak, which Bhullar calls "this insane sort of snout that they have."

To hunt for clues about the origin of the beak, the researchers have been studying various kinds of animal embryos, from birds like emus and chickens to nonbird reptiles like alligators, which are birds' closest living relatives.

Their work led them to two specific genes. These genes are active in the middle of the face-forming region of bird embryos, but not in the middle of that region in the embryos of other animals.


SCIENCE
Big Flightless Birds Come From High-Flying Ancestors

The team did an experiment to see what would happen if they blocked the effect of that localized gene activity in chicken embryos.


SHOTS - HEALTH NEWS
Birds Of A Feather Aren't Necessarily Related

Bhullar says he remembers the night he put the altered, developing chicks under a microscope, and saw that they had unusual, broad snouts.

"That was a pretty remarkable moment," he recalls. "That's a moment that will stay with me, I think."

Instead of the normal bone structure that would form a beak, he says, these protochickens had a pair of small, rounded bones that looked "like those in a dinosaur, like archaeopteryx or velociraptor, or in any other reptile — like an alligator."而不是正常的骨骼結構,將形成喙,他說,這些protochickens有一對小而圓的骨頭,看起來“像一個恐龍,始祖鳥一樣迅猛或,或以任何其他爬行動物 - 鱷魚般的”

A report on the study appears this week in the journal Evolution. But don't expect the scientists to create lab-grown dinosaurs — that would be a whole lot harder than just trying to restore some of the traits that existed in the first birds.

2015年5月12日 星期二

On planes, savory tomato becomes favored flavor


May 12, 2015

On planes, savory tomato becomes favored flavor
ByBlaine Friedlander


Dando


Yan

Airline passengers who eat meals vary in their ability to taste sweet, sour, bitter and salty flavors. In studying how airplane noise affects the palate, Cornell food scientists have found sweetness suppressed and a tasty, tender tomato surprise: umami.

A Japanese scientific term, umami describes the sweet, savory taste of amino acids such as glutamate in foods like tomato juice, and according to the new study, in noisy situations – like the 85 decibels aboard a jetliner – umami-rich foods become your taste bud’s best buds.

“Our study confirmed that in an environment of loud noise, our sense of taste is compromised. Interestingly, this was specific to sweet and umami tastes, with sweet taste inhibited and umami taste significantly enhanced,” said Robin Dando, assistant professor of food science. “The multisensory properties of the environment where we consume our food can alter our perception of the foods we eat.”

With Dando, Kimberly Yan, MPS ’14, co-authored the study, “A Crossmodal Role for Audition in Taste Perception,” published online in March in the Journal of Experimental Psychology: Human Perception and Performance. The research will appear in a forthcoming print edition of the journal.

The study may guide reconfiguration of airline food menus to match these loud environments – in other words, make airline food taste better. Auditory conditions in air travel actually may enhance this sought-after taste, the researchers found. In contrast, in sweet taste ratings, exposure to the loud noise condition resulted in a pronounced suppression of taste intensity – the sweet sense was dulled.

Airlines acknowledge the phenomenon. German airline Lufthansa had noticed that passengers were consuming as much tomato juice as beer. The airline commissioned a private study released last fall that showed cabin pressure enhanced tomato juice taste.

Taste perception depends not only on the integration of several sensory inputs associated with the food or drink itself, but also on the sensory attributes of the environment in which the food is consumed, the scientists say.

Said Dando: “The multisensory nature of what we consider ‘flavor’ is undoubtedly underpinned by complex central and peripheral interactions. Our results characterize a novel sensory interaction, with intriguing implications for the effect of the environment in which we consume food.”

Upsetting the Apple car

Google has been working for years on driverless cars, and reveals only eleven minor accidents in six years of trials. But it will be tough to overturn the incumbents in a business where clever technology is only part of the equation. It is the established carmakers, not tech firms, that will win the race to build the vehicles of the future  http://econ.st/1zWrrjn

APPLE’S ability to make desirable iGadgets designed for easy portability is beyond question. Reports emerged this week that it is planning to make a mobile device...
ECON.ST

RESEARCHERS MAKE KEY DISCOVERY TO IMPROVE PHARMACEUTICALS PRODUCTION

Wednesday, May 6, 2015

CMU RESEARCHERS MAKE KEY DISCOVERY TO IMPROVE PHARMACEUTICALS PRODUCTION

amino acids
A pair of Carnegie Mellon researchers have made a key discovery about amino acids, the most basic building blocks of life. For centuries, scientists have been perplexed by the fact that amino acids in living organisms exist exclusively in only one of two possible forms, or “enantiomers.” The researchers’ findings on how this may have come about in nature could also lead to the production of better pharmaceuticals, and were published in this week’s edition of Nature Chemistry.
“Pharmaceuticals are a 300 billion dollar industry, and rely on the ability to make one enantiomer in a drug, not a mixture of both,” said Andrew Gellman, the principle investigator of the study from the Department of Chemical Engineering at Carnegie Mellon. “If you make a drug that has both enantiomers and ingest it, one of them might be therapeutic, but the other probably isn’t. In fact it could be highly toxic.”
Enantiomers, commonly termed “left-” or “right-handed,” are molecules that are mirror images of each other, but they are not exact replicas and thus take on different properties when ingested by people or living organisms. When amino acids or pharmaceuticals are synthesized in laboratories, both enantiomers are produced and it is exceedingly difficult to separate the two.
But in this study, researchers were able to successfully produce a highly-purified mixture of “left-handed” enantiomers by reacting a gas consisting of slightly more “left-handed” enantiomers than “right-handed” ones with the surface of a piece of copper. This small initial imbalance was amplified after interacting with the copper surface, in spite of the fact that this copper surface is not “handed.”
“You could do this in a distillation-like process to make a substance more and more exclusively one-handed,” Gellman said. “This could be very useful for the pharmaceutical industry. But it also helps explain how the ‘primordial soup’ in which life began went in the direction of one-handedness.”
Gellman co-authored the study with Yongju Yun, who earned a Ph.D. in Chemical Engineering at Carnegie Mellon and is now a postdoctoral researcher at the University of California, Berkeley. 

2015年5月9日 星期六

Audi Just Invented Fuel Made From CO2 and Water

A research facility has managed to create the first batches of diesel fuel with net-zero carbon footprint.
The next step for the project will be industrial scale production.
TI.ME

2015年5月7日 星期四

Science,College Walk, Columbia University


Science is looking happier now that he's not standing in the snow outside the gates on College Walk. Photo by @migayesa.

2015年5月6日 星期三

鍍金洋蔥細胞所製造出來的人工肌肉,可以同時進行彎曲與擴張


「洛杉磯時報」報導,由台灣大學應用力學所教授張培仁和台灣大學機械系教授施文彬所帶領的研究顯示,透過鍍金洋蔥細胞所製造出來的人工肌肉,可以同時進行彎曲與擴張。(取自www.latimes.com)

「洛杉磯時報」報導,由台灣大學應用力學所教授張培仁和台灣大學機械系教授施文彬所帶領的研究顯示,透過鍍金洋蔥細胞所製造出來的人工肌肉,可以同時進行彎曲與擴張。(取自www.latimes.com)

(中央社記者吳協昌洛杉磯6日專電)一項由台灣大學進行的研究,今天在美國掀起浪潮,並且在美國的「應用物理學快報」中刊登。這項研究顯示,使用鍍金洋蔥細胞,可以製造人造肌肉。

「洛杉磯時報」今天報導,過去的人造肌肉,無法同時進行彎曲以及擴張的動作,但透過鍍金洋蔥細胞所製造出來的人工肌肉,可以同時進行彎曲與擴張。

這項研究是由台灣大學應用力學所教授張培仁和台灣大學機械系教授施文彬所帶領的團隊所進行,施文彬對洛杉磯時報說,總的來說,鍍金洋蔥細胞能夠伸張收縮與彎曲,就像人類肌肉一樣。

報導中指出,目前的人造肌肉主要是透過各種的聚合物來製造,但代價昂貴,也無法運作得很好,因此施文彬團隊決定尋找更方便、便宜的方式製作。

施文彬說,小學時都曾經在顯微鏡下觀察洋蔥細胞,因此在選擇新的製作方式時,就想到使用洋蔥細胞。

這項研究已經刊登在應用物理學快報( Applied Physics Letters)上,這是由美國物理協會出版發行的期刊。

施文彬團隊在這項研究中,先去除洋蔥細胞的半纖維素,然後在洋蔥表皮的兩面鍍金,再透過電流操作,讓洋蔥細胞可以跟肌肉一樣伸縮與彎曲;也以兩面不同厚度的鍍金,讓兩面的細胞硬度不同,讓他們能夠控制肌肉的反應。

施文彬也對洛時說,電鍍金與洋蔥肌肉都具有生物相容性,因此未來可以朝向生物醫藥方面運用,也許可以用在機器人身上。1040506
刊登在「應用物理學快報」的研究原文報導:Onion artificial muscles

2015年5月1日 星期五

the neuroscience of bat flight


A Columbia University study examined the neuroscience of bat flight and showed sensory receptors in wings provide tactile feedback that optimizes flight control.
12,218 次觀看
Can bats teach aircraft designers a thing or two? Learn how understanding the neuroscience of bat flight could help us design better planes. Read more:http://newsroom.cumc.columbia.edu/…/flying-with-brains-how…/