Science-Videos

Time is real, the laws of physics can change and our universe could be involved in a cosmic natural selection process in which new universes are born from black holes, renowned physicist and author Lee Smolin said.

His views are contrary to the widely-accepted model of the universe in which time is an illusion and the laws of physics are fixed, as held by Einstein and many contemporary physicists as well as some ancient philosophers, Prof. Smolin said. Acknowledging that his statements were provocative, he explained how he had come to change his mind about the nature of reality and had moved away from the idea that the assumptions that apply to observations in a laboratory can be extrapolated to the whole universe.

The debate had sometimes taken a metaphysical turn, he said, in which the idea that time is not real had led some to conclude that everything that humans value – such as free will, imagination and agency – is also an illusion. "Is it any wonder that so many people don't buy science? This is what is at stake," he said.

Robert Green, Division of Genetics, Brigham and Women's Hospital and Harvard Medical School; Associate Director for Research, Partners HealthCare Center for Personal Medicine

Scientists have built and tested robotic ants, which they say behave just like a real ant colony.

The robots do not resemble their insect counterparts; they are tiny cubes equipped with two watch motors to power the wheels that enable them to move. But their collective behaviour is remarkably ant-like.

In this clip, lead researcher Dr Simon Garnier from the New Jersey Institute of Technology explains how the robots were designed to mimic the way in which an ant colony navigates.

Just like ants, he explains, the robots "work together" to find their way from A to B - each one leaving a light trail that others follow.

Viruses are biological pirates, invading cells and hijacking their machinery to reproduce and infect again. Research at Harvard Medical School is shedding new light on the battle line where viral and cell membranes meet, and the key role of a protein grappling hook with which the influenza virus commandeers its prize—your cells.

An influenza virus is a collection of eight RNA strands enclosed in a lipid-bilayer membrane. When the virus encounters a cell—in your lung, for example—that cell may engulf the virus inside an internal membrane called an endosome. To escape that bubble, the virus fuses its membrane with the endosome's, opening a window into the cell's interior. Once free, the viral RNA is copied, and the hijacked cell begins to manufacture copies of the virus. To fuse the two membranes, the virus carries a protein called hemagglutinin (the "H" in H1N1). Triggered by the acidic environment of an endosome, that protein will extend from the viral membrane and attach, like a grappling hook, to the endosome's membrane. When enough hooks are set, they draw the membranes together until they fuse The flu virus carries about 300 to 400 of these hooks, and virologists had known that several are needed to fuse the membranes.

In their latest study, reported last month in the new journal eLife, the HMS team show why. Using a microscope developed by first author Tijana Ivanovic, a research fellow in the HMS Department of Biological Chemistry and Molecular Pharmacology, the team looked closely at changes in the protein throughout its assault on the endosome. They observed that three or four hemagluttinin hooks must attach in close proximity to fuse the membranes. Without the help of neighbors, an individual hook is too weak to pull the membranes together. Instead, they observed, the protein remains stretched between the two membranes, like a bridge. And that's an intriguing target, said Stephen Harrison, the study's senior author and the Giovanni Armenise-Harvard Professor of Basic Biomedical Science in the department of Biological Chemistry and Molecular Pharmacology at HMS. "That bridge can hang out there for as long as a minute," Harrison said. "That makes it an interesting target for an inhibitor, in principle, at least, because it's there for long enough to be targetable." The study also appears to settle a question about the nature of the hemagglutinin protein, and viral fusion: Are multiple hooks needed because they interact directly with each other to fuse the membranes, or because that's the number required to pull the somewhat elastic membranes together by brute force? The researchers' answer: brute force. "That observation helps us distinguish between classes of models for a stage of the fusion process," Harrison said. "That notion is probably fundamental to all viral fusion proteins—or for that matter to most cellular membrane fusion events facilitated by proteins."

Dr. Hearn give an overview of his program - Optimization and Discrete Mathematics at the AFOSR (Air Force) Spring Review 2012. 

• Discusses the cutting edge of optimization
• 25% of all scientific programming is spent on linear programming problems
• metamaterial design
• Describes the value of the travelling salesman problem and how they can take two local optima and make the move the next local optima using non-quantum systems
• Cracking or making a dent on travelling salesman problems means progress on all NP-complete problems.
• Band gap optimization
• photonic materials and crystalline structures
• circuit design
• improve drugs and manufacturing

Free biology talks by the world's leading scientists. Our mission is to produce a library of outstanding science lectures. We will add 15-20 seminars per year in a wide-range of biology topics. Access, through web streaming or download, is completely free-of-charge. Also check out our iBioMagazine channel, where you can watch ~10 minute talks about the human-side of science.

What made Einstein Einstein? With access to rare medical slides and photographs of the great scientist’s brain, researchers seek out the biological roots of genius in Einstein’s brain. What might Einstein’s brain have in common with young math whizzes today? How does the anatomy of David Pogue’s brain measure up to one of the greatest brains of all time? And can we discern whether peculiarities in Einstein’s brain are gifts of nature, fruits of nurture, or both?

4 lectures entitled "An Introduction to BioMEMS and Bionanotechnology". These lectures serve as an introduction to some of the key concepts of bio-chips, biosensors, bioMEMs, and bionanotechnology.

"The USC-Lockheed Martin Quantum Computing Center has taken delivery of a D-Wave One adiabatic quantum computer. In this talk, we will report on our experience assessing the quantum mechanical behavior of the device and benchmarking its performance. We will present experimental results that strongly indicate that quantum annealing is indeed being performed by D-Wave One, and show how the device performs when compared to classical computers on a particular optimization problem. We will also discuss a proposal to experimentally show the presence of entanglement that is being developed in collaboration with D-Wave. We will also report briefly on early work to find applications for the D-Wave One, and other challenges to broad use of this new technology."

Thea Tlsty, UCSF Professor of Pathology, explains the biology of cancer; that cancer arises primarily through damage to the genetic program of our cells, how this leads to uncontrolled growth and invasion, how cancer intrudes upon and destroys adjacent or distant tissues, and how the inner workings of the cancer cell function. Series: "UCSF Osher Mini Medical School for the Public" [1/2012]

Professor Jim Al-Khalili explores how the mysteries of quantum theory might be observable at the biological level. 

Although many examples can be found in the scientific literature dating back half a century, there is still no widespread acceptance that quantum mechanics -- that baffling yet powerful theory of the subatomic world -- might play an important role in biological processes. Biology is, at its most basic, chemistry, and chemistry is built on the rules of quantum mechanics in the way atoms and molecules behave and fit together. 

As Jim explains, biologists have until recently been dismissive of counter-intuitive aspects of the theory and feel it to be unnecessary, preferring their traditional ball-and-stick models of the molecular structures of life. Likewise, physicists have been reluctant to venture into the messy and complex world of the living cell - why should they when they can test their theories far more cleanly in the controlled environment of the physics lab?

But now, experimental techniques in biology have become so sophisticated that the time is ripe for testing ideas familiar to quantum physicists. Can quantum phenomena in the subatomic world impact the biological level and be present in living cells or processes - from the way proteins fold or genes mutate and the way plants harness light in photosynthesis to the way some birds navigate using the Earth's magnetic field? All appear to utilise what Jim terms "the weirdness of the quantum world".

The discourse explores multiple theories of quantum mechanics, from superposition to quantum tunnelling, and reveals why "the most powerful theory in the whole of science" remains incredibly mysterious. Plus, watch out for a fantastic explanation of the famous double slit experiment. 

Watch this video on the Ri Channel with additional learning materials:
http://bit.ly/X826sE

Columbia University undergraduate virology course from 2012. In this lecture we define viruses, explore their origins, and summarize their functions and components.