Watch the video above to see a very recent advance in molecular science — the kind that would take months or years to reach classrooms before the edge of human knowledge moved online.
The researchers placed a thin film of water containing single stranded DNA molecules between a glass surface and a metal-coated base. By heating a spot on the base with an infrared laser a thermal gradient is created in the fluid layer, with cooler fluid at the top. This pushes the DNA molecules towards the top of the film. The laser is then scanned in a radial pattern from the centre; as the laser spot moves it heats up the fluid locally causing changes in viscosity which result in contraction and expansion of the fluid either side of the moving spot, which causes the fluid to flow outwards, away from the centre. The layer of fluid above this moving ‘belt’ moves in the opposite direction to conserve mass. In this way, the molecules, which have been drawn to the upper layer of the fluid by the initial heating, are pulled towards the central spot, where they accumulate.
Weinert and Braun showed that high concentrations of DNA can be accumulated within a few seconds when carried on the conveyor. ‘The mechanism does not require microfluidics, electrodes, or surface modifications,’ the researchers say. ‘As a result, the trap can be dynamically relocated. The optical conveyor can be used to enhance diffusion-limited surface reactions, redirect cellular signalling, observe individual biomolecules over a prolonged time, or approach single-molecule chemistry in bulk water.’
It is stunning that this first of its kind image and description of how it was taken can be studied by anyone with an internet browser — almost immediately upon its discovery. It will be many months at least before this new insight into and picture of molecules will be delivered to students in a printed textbook.
The machine in the illustration is an Atomic Force Microscope (AFM) explained by physicist Ethan Siegel at his StartsWithABang blog. Siegel describes how the AFM works: “Basically, you make a tiny, sharp, atomic needle that you move over the top of a molecule. When you approach different atoms in a molecule, the electric forces either attract or repel the needle. As the needle moves up and down, the handle that it’s attached to feels forces and torque. So, all you have to do is measure these tiny changes in force and torque, and you can image the molecule beneath it.”
The gray inset image is what the AFM let’s us see. Siegel comments that: “You can even see that the electrons like to live on the outside edges of the carbon rings, and that there are fourteen tiny hydrogen atoms bonded to the carbon atoms at various points. What an amazing picture; the entire molecule is only 1.4 nanometers across!”
The inset image is from BBC’s report of 8/28/09 titled “Single molecule’s stunning image.” Several developing concepts are highlighted in the BBC report, each of them offering potential for nano technologies where work will be done at the molecular level. A post at Gizmodo by Jack Loftus explains why what is displayed in the inset images is a stunning breakthrough: “That B&W structure is an actual image of a molecule and its atomic bonds. The first of its kind, in fact, and a breakthrough for the crazy IBM scientists in Zurich who spent 20 straight hours staring at the ’specimen’—which in this case was a 1.4 nanometer-long pentacene molecule comprised of 22 carbon atoms and 14 hydrogen atoms.”
Near the top of the left sidebar of this page is the entrance to the expanding GoldenSwamp Study Subjects section. I am now spending a couple of weeks building that section from my EdClicks study links that I have been collecting since 2002. The links I have and will continue to collect are samples of the superior learning links available online. You are welcome to click into the collection as it is being built now. Hopefully it will be a useful source into the future for those of us dedicated to showing the high quality of online study subject materials.
It has been fascinating for me to go through the links I have collected in the past. Almost all of them are still active, and I would say most of them have been well kept up over the years. Many were at the cutting edge when they were first created years ago — and remain so. Clearly their keepers are individuals or teams of expert Web developers and content devotees.
New Mobile Learning Content Community Resource Available mLearnopedia.com partners with TechEmpower to provide information source for mobile learning
Greenville, WI February 16, 2009: With an increasingly mobile society and the need for instant information for employees and students everywhere all the time, mobile learning and mobile performance support are growing at a rapid pace. Ambient Insight recently reported that the US market for Mobile Learning product and services is growing at a five-year compound annual growth rate (CAGR) of 21.7%.
To provide access to the latest news and best practices a new content community has been created at http://cc.mlearnopedia.com. Content is aggregated from sites such as Cell Phones in Learning, GoldenSwamp, mLearning is Good, mLearning World, mLearnopedia, moblearn, Mobile Commons, and MobileDot. “The mlearnopedia project is a terrific idea at the right time! I look forward to being part of it,” states Judy Breck from Golden Swamp. Ben Bonnet from mLearning is Good commented “The cc.mlearnopedia.com community has already benefited me by providing exposure to content I normally would have missed.” The aggregation technology, called BrowseMyStuff, comes from Tony Karrer of TechEmpower with the support of Judy Brown from mLearnopedia.com.
For essentially anything about mathematics, you can find a precise, concise node about it, a node enhanced by hyperlinks to related equally crisp and accurate nodes, at WolframMathWorld. With justifiable pride, this marvelous mathematical network calls itself the web’s most extensive mathematics resource.
The Connected Graph detail image enters the WolframMathWorld through a cluster of Small World Network subjects, which are part of graph theory, in discrete mathematics. The Small World cluster provides the math behind six degrees of separation, the Kevin Bacon Game, and hyperlinking patterns in the internet.
Honest, I didn’t make up that word: I found it this morning on my RSS feed from Merriam-Webster’s Word of the Day. The experts there tell us that frigorific is an adjective meaning : causing cold : chilling. This morning it is 14 degrees here in New York City — definitely frigorific.
A half century ago when I was a student at El Paso, Texas’ Austin High School, Mrs. Emma Burtis taught a class called 7B English. Mrs. Burtis was also sponsor of the school’s club for student writers. Mrs. Burtis had her own word-of-the-day, on steroids! We rushed to get seated in her classroom as early as we could, because each class session (more…)
A little tour narrated by quarking ducks introduces CERN with an interactive show: “Particle Physics – A Keyhole to the Birth of Time.” The duck show is part of CERN’s website which describes Europe’s collaborative work in particle physics. CERN is the home of the Large Hadron Collider (LHC), which is expected to make fundamental physics discoveries possible in 2009. The quick tour by the ducks is a good way to get started in following LHC in the new year.
Quarked Adventures in the Subatomic Universe teaches particle physics in simple terms. There are games and other activities for small children, but the Subatomic Universe Roadmap and the Glossary integrated with the map are an excellent introductory primer for anyone on the subatomic structure of the world around us and the cosmos.
In his powerful heads-up book Jump Point, Tom Hayes writes (p. 11) that experts forecast that Web-enabled mobile phone adoption can “easily reach the three billion mark by the Jump Point year 2011, attaining an astounding five billion worldwide users by 2015.” [italics Hayes']. He further tells us that the “third billion” people who will come online within the next 1,000 days will have “never been in a classroom, owned a book, or read more than a few signpost words.” (p. 22) This learning deficit will be even more true of the fourth and fifth billion. These billions will include most of the children of the new generations.
Obviously, there is no way to build schools by 2011 or 2015 for these billions of people who do not have an education. They will essentially all, however, have a mobile phone. At the least, the mobiles the new internet participants have can provide the literacy input Abe Lincoln (born 1809) was limited to as a boy in the rugged pioneer settlements of Kentucky and Indiana. In his biography Lincoln, David Herbert Donald describes the poverty of education available to the youngster:
. . . his teachers, transient and untrained as they were, helped him master the basic tools so that in the future he could educate himself. Dilworth’s Spelling Book, which he and [his older sister] Sarah had begun to use in Kentucky, provided his introduction to grammar and spelling. Beginning with the alphabet and Arabic and Roman numerals, it proceeded to words of two letters, then three, and finally four letters. From these the student began to construct sentences like: “No man may put off the law of God.” Dilworth’s then went on to more advanced subjects, and the final sections included prose and verse selections, some accompanied by crude woodcuts — which may have been the first pictures Abraham Lincoln had ever seen. Other readers, like The Columbian Class Book and The Kentucky Preceptor, expanded and reinforced what he learned from Dilworth’s.
As Lincoln grew through his childhood and adolescent years he had very little schooling. He read books when he could get them, but they were rare in the rough farming environment where he remain until he was in his twenties.
Today, 200 years later, many of the third, fourth, and fifth billion who will come online in the next six years are strikingly similar in their experience with education to young Lincoln. The huge difference is that today’s billions will have mobile phones that will provide them with everything Dilworth’s gave Lincoln, all the books they could possibly read, and much, much more.
On Bill Thayers Web Site he explains that LacusCurtius: Into the Roman World which is his creation is: a major site on Roman antiquity, including a photogazetteer of Roman and Etruscan cities and monuments (with a very large site on the city of Rome of course); a site for teaching yourself to read Latin inscriptions; the complete Latin texts of [major authors, and much more].
One way people find LacusCurtius is through MIT Open Courseware (OCR) where the collection is recommended on the Ancient World: Rome course for: More ancient sources in translation; useful collections of photos of Latin inscriptions and theatres inter alia; a few old secondary works on ancient Rome.
Visit the page here at MIT Open Courseware for digital tools like the one illustrated above. There are more than two dozen tools for topics ranging such as precalculus, algebra and vectors, curves, surfaces and differential equations. Math
The Smithsonian American Art Museum hosts the website here where you can: “Take a virtual journey to meet American Indians of the 1830s with artist, ethnologist, and showman George Catlin. This site compiles paintings, historical documents, and commentary from contemporary experts so you can explore the intersections of two cultures, both in Catlin’s time and today.” History
Continuing its good habit of putting superior open science learning materials online, Cold Spring Harbor Laboratory’s Silencing Genomes sets out new principles of genetic science. The tutorial focuses on RNAi, discovered in the roundworm C. elegans. via Scout Report, Molecules and cells
Tufts University offers Opencourseware for a variety of scientific and other subjects. One of the courses, which you can click to is Rodent and Small Mammal Medicine. The webpage that a click will lead you to has valuable information on the diseases and treatment of the smallest animals we humans keep as pets. It also has this quotation from from David L. Graham, D.V.M. PhD.:
“Now, ponder, please that thought of the Bard’s ‘what’s in a name?’ Like, for example, ‘Pocket Pets’? In my humble opinion all veterinarians should abjure use of the term ‘pocket pets.’it is (at least to me and few colleagues) offensive and denigrating to the inherent uniqueness and dignity of those creatures that happen to be of such small size that they can fit into a pocket. The term suggests that such pets can be maintained in a more casual and less careful, less caring, and less thoughtful manner than is required for maintenance of other, more traditional companion animal species. Such creatures are of no lesser biological and moral consequence than are larger, more traditional pets. I’m sure that the cute alliteration of the term is a major reason for its acceptance, but I urge that some other rubric(s) be coined under which to group these relatively diminutive companion animals. Please, they are sugar gliders, gerbils, hedgehogs, mice (‘wee sleekit beasties’ – R. Burns), small pets, little small animals (to differentiate them from dogs and cats which are merely ’small animals’), minipets …but please…not ‘pocket pets.’”
Weinert and Braun showed that high concentrations of DNA can be accumulated within a few seconds when carried on the conveyor. ‘The mechanism does not require microfluidics, electrodes, or surface modifications,’ the researchers say. ‘As a result, the trap can be dynamically relocated. The optical conveyor can be used to enhance diffusion-limited surface reactions, redirect cellular signalling, observe individual biomolecules over a prolonged time, or approach single-molecule chemistry in bulk water.’
