Sally Ride, America’s First Female Astronaut in Space, Dies

Sally Ride, the first American female astronaut in space passed away today after a 17 month battle with pancreatic cancer. According to her website, Sally Ride Science:

Sally Ride died peacefully on July 23rd, 2012 after a courageous 17-month battle with pancreatic cancer. Sally lived her life to the fullest, with boundless energy, curiosity, intelligence, passion, joy, and love. Her integrity was absolute; her spirit was immeasurable; her approach to life was fearless. 

Sally Ride
Sally Ride (Courtesy Wikimedia Commons)

Ride was a “trailblazer” in so many ways. In 1983 she joined the crew of the Space Shuttle Challenger at the age of 32. At that time she was not only the first woman in space, but also the youngest person to do so. The influence she had on her colleagues is so evident in the many quotes posted on NASA’s website.

Sally Ride broke barriers with grace and professionalism – and literally changed the face of America’s space program,” said NASA Administrator Charles Bolden. “The nation has lost one of its finest leaders, teachers and explorers. Our thoughts and prayers are with Sally’s family and the many she inspired. She will be missed, but her star will always shine brightly.

Sally was a personal and professional role model to me and thousands of women around the world,” said NASA Deputy Administrator Lori Garver. “Her spirit and determination will continue to be an inspiration for women everywhere.

The selection of the 1978 Astronaut Class that included Sally and several other women, had a huge impact on my dream to become an astronaut. The success of those woman, with Sally paving the way, made my dream seem one step closer to becoming a reality,” said Peggy Whitson, Chief of the NASA Astronaut Office.

Ride’s influence on the world did not end with NASA. She went on to join the faculty at the University of California, San Diego, as a professor of physics and director of the University of California’s California Space Institute. She later founded her own company Sally Ride Science, which encouraged girls and young women to pursue careers in science and math. She lived a very private life, but what she gave of herself was for the good of people and our world. Her dedication to education and teaching is truly exemplary.

As most of us know, pancreatic cancer is a particularly difficult cancer and so much more work needs to be done to beat this horrible disease. Sally Ride Science has set up a fund in honor of Sally Ride, which can be found at https://www.sallyridescience.com/sallyride/memory.

Scientists Create Silicone Jellyfish From A Rat’s Heart Muscle

Yes, there might be protests as scientists are ‘playing God’ again, but the news is too exciting to stoop to such petty protests. Scientists have mimicked the movement of a mammalian heart and made an artificial jellyfish, which can swim using the exact movements that the heart undergoes when it pumps blood. The body of the jellyfish is made up of silicone with cardiac tissue from a rat mounted on this scaffolding.

The Medusoid

Heart and the Jellyfish

The researchers from Harvard University and California Institute of Technology (Caltech) noticed the similarities between the pumping motion of a heart and the pumping motion that helps a jellyfish swim. This is the latest in the emerging field of synthetic biology. Says Kevin Kit Parker, one of the people involved in the study:

I started looking at marine organisms that pump to survive. Then I saw a jellyfish at the New England Aquarium and I immediately noted both similarities and differences between how the jellyfish and the human heart pump.

And thus was born ‘Medusoid’. The main challenge was the lack of understanding of how the heart muscles actually co-ordinate themselves via electrical signals. Then they performed something called ‘reverse engineering’. To understand how a medusa jellyfish really swims and how the muscles are all co-ordinated, the team used techniques from biometrics and crystallography. They were also able to understand the exact biomechanics of the propelling muscle contractions.

Mimicking as much as possible (Taken from the paper)

Getting everything to work together

It turns out that the mammalian heart muscles move in much the same way when they pump blood. Thus, the plan was to make the jellyfish out of cultured cardiac tissue taken from a rat. Silicone would provide the scaffolding that the structure needed. Then they matched the Medusoid with a real medusa jellyfish, part by part. They made sure that the Medusoid was a copy as long as cellular architecture went.

Cellular architecture has to match – and they do!
(Taken from the paper)

Less tricky was the design of the silicone structure. They had to ensure that the structure pushed water efficiently, like the jellyfish has evolved to do. Too much gap between the ‘legs’ and water would just ‘leak’ through. Too little and you’d just be wasting precious power for thrusting. The cardiac muscles were stimulated by electrical signals.

The work has been reported in Nature Biotechnology in this paper. Lead author of the paper is Janna Nowroth, a research student. His PhD advisor John Dabiri, an expert of biopropulsion is also an author of the paper. Kevin Kit Parker, another coauthor, is an expert in the field of tissue engineering. He had created artificial ‘organisms’ that can grip and pump. The jellyfish was really ambitious!

So what’s the next step? Endowing the jellyfish with something that even it doesn’t have – a brain. The team wants to put a small control center for the nerves so that it can decide where it wants to go.

Additional infohttp://www.nature.com/news/artificial-jellyfish-built-from-rat-cells-1.11046

Researchers Build First Complete Computer Model of an Organism

Researchers at Stanford University have completed the world’s first complete computer model of an organism. Using research from 900 publications and accounting for over 1900 parameters, they were able to completely simulate the human pathogen, Mycoplasma genitalium. This pathogen is often found in the urinary or respiratory tracts of humans and is known to have the simplest genome of any free-living organism.

Phenotype Model
This image represents the many processes it takes to build a complex phenotype as was done in this study. (Courtesy Science Direct Journal Cell)

The study was partly funded by the NIH Director’s Pioneer Award. “This achievement demonstrates a transforming approach to answering questions about fundamental biological processes,” said James M. Anderson, director of the National Institutes of Health Division of Program Coordination, Planning and Strategic Initiatives. “Comprehensive computer models of entire cells have the potential to advance our understanding of cellular function and, ultimately, to inform new approaches for the diagnosis and treatment of disease.”

The study consisted of vast amounts of data and took a lot of computing power to pull off. But you may ask, “Why are we so interested in simulating an organism?” That is a good question. In the simplest of terms, what these scientists are building is called a phenotype, which basically means they are building a model based on observed behaviors or expressions in this organism. Using data from more than 900 scientific papers to account for every molecular interaction that takes place in the life cycle of Mycoplasma genitalium, the scientists were able to observe things in the computer model that would be hard to see in the real thing. They were also able to reexamine experimental data.

This study opens wide the possibilities of computer aided bio-engineering. If you’ve been around any construction or architectural firms, you know the impact that computer aided design (think AutoCAD) has contributed to the process of planning and engineering a building. In the same way, being able to simulate entire organisms and be able to predict what certain genes will do under certain conditions has so much potential for future applications such as pharmaceuticals and even personalized medicine. However, the study authors are cautious to note that it will be a while before this is possible.

This study was published in the journal Cell. For more information, see Stanford University’s website.

NASA Reveals Stunning Photos of Sun’s Corona

NASA captured stunning images of the sun’s corona, the million degree atmosphere surrounding the sun, from a 16 megapixel telescope called the HI-C. The telescope was launched on a sub-orbital rocket from White Sands Missile Range in New Mexico. The mission only lasted 620 seconds, but the results were pretty impressive. NASA was able to capture the highest ever resolution images of the sun’s corona using the extreme ultraviolet wavelength. This wavelength of light is optimal for viewing the hot solar corona.

Corona
NASA captured the highest resolution images of the sun’s corona ever captured. (Courtesy NASA.GOV)

The mission’s purpose was to capture the images of the sun’s corona to determine how coronal activity affects the earth’s atmosphere. According to a NASA press release, Jonathan Cirtain, senior heliophysicist at NASA’s Marshall Space Flight Center in Huntsville, Ala said,”we have an exceptional instrument and launched at the right time…because of the intense solar activity we’re seeing right now, we were able to clearly focus on a sizeable, active sunspot and achieve our imaging goals.”

The High Resolution Coronal Imager (HI-C) was able to capture images that were 5 times more detailed than any previously taken. The mirrors used in the telescope’s optics array are being credited for the incredible footage. Initially developed at NASA’s Marshall Space Flight Center, the final mirror configuration was a joint effort between Smithsonian’s Astrophysical Observatory (SAO) in Cambridge, Mass, Marshall Space Flight Center, and the University of Alabama in Huntsville.

Below, you can see a very short video released by NASA showing the detailed images of the solar corona.

NASA’s suborbital sounding rockets are proving to be a lower cost, yet effective means for exploring space. It will be interesting to see what other new information can be gathered using the HI-C telescope. For more information on NASA’s solar missions, visit http://www.nasa.gov/sdo.

Our Skin Can Tell Time

That our body has ‘clocks’ is known. The best known is the circadian ‘day-night’ clock that regulates our sleep patterns and allows to anticipate environmental changes between day and night. Scientists have now found that skin cells also have an internal ‘clock’.

Skin as a Protective Barrier

Because the skin is the outermost layer of the body, it is most affected by environmental variations in conditions such as temperature, UV and sunlight. In fact, one of its main functions is to protect the body by forming a barrier to harsh environmental conditions. Wouldn’t it thus make sense for the skin to ‘sense’ changes in the environment and respond accordingly?

Some Skin Genes are Time-Dependent

Researchers in Hamburg measured the expressions of various genes in skin cells at different times of the day, and found a whole bunch of genes that were expressed differently depending on the time of the day. This means that the skin adapts to the current environment and regulates itself on the current need. Just as our clothes very with the weather, the suite of proteins and fats expressed by the skin vary according to the time of day.

[Image Credit: Getty Images]

They also found that many of these daytime-regulated genes were regulated by one other gene. This gene is a transcription factor, which means it doesn’t directly produce a protein, but regulates the expression of other proteins, either by inhibiting them or activating them. That is, the gene called Klf9 is a parent regulator—it is affected by the environment, and in turn, it affects the expression of other genes. However, we don’t yet know how these changes lead to differences in the activity of the skin at different times and that remains to be studied.

The job of the biological clock is to control the exact timing of various processes like cell division and DNA repair in skin. Prof. Achim Kramer, who headed this research, is already looking to the future: “If we understand these processes better, we could target the use of medication to the time of day in which they work best and have the fewest side effects.”

Of Mice and Men: Studying Infections by Making Mice More Human

How do disease-causing pathogens act inside our bodies? How do we study mechanisms of infection and immunity in various human diseases? Using human patients as lab rats is not possible, and thus researchers have come up with a better way of using actual lab rats to study infectious diseases.

Implanting Human Immune Responses in Mice

The efficacy of a vaccine on humans could be better studied if tested on an organism that resembled humans closely. It was in 2006 that mice were first ‘humanized’. Mice were implanted with human liver and thymus tissue, and hematopoietic stem cells. These mice were called BLT mice — Bone marrow, Liver and Thymus. The thymus and the liver are the centers of the immune system response; the thymus serves as the ‘training ground’ for immune T-cells. The implanted stem cells recognize the human immune tissues in the mice and lead to formation of human-like immune cells (called T-cells).

BLT ‘humanized’ mice may play an important part in biomedical research. [Image Credit: University of North Carolina, Chapel Hill]

How Do Human Cells Respond to a Virus in a Mouse Body?

Though these mice contained human immune system cells, it was not known if the response of these cells inside a mouse body would mimic human responses. This would be essential to study human diseases. To study this, Boston researchers infected these mice with the  virus HIV-1 and characterized the responses of these mice. They found that the immune system of these mice behaved in a way very similar to that of humans upon HIV infection. In addition, humans with a certain type of immune cells can recognize the virus better and live longer on infection. Now, mice with these cells also showed the same behaviour compared to other mice.

A large percentage of failures in human trials arise because of vaccines behave differently in the human body compared to other organisms. Using BLT mouse models that accurately reflect human immune system responses could weed out many of these false positives and speed up biomedical research.

NASA May Be Blind When The Mars Rover Curiosity Lands On Mars

NASA’s craft might be in for a crash landing, but NASA won’t know about it till quite later! Yes, the landing of the new Mars Rover, Curiosity, on the Gale crater might be blind. NASA will lose real-time system coverage owing to a maneuvering glitch last month, which has put the craft onto a different orbit.

The face of Curiosity

Those seven minutes

The entry into Mars’ atmosphere, descent onto the surface and the final landing procedure will all take place in seven minutes. The duration that NASA has dubbed ‘seven minutes of terror’.

What about the other eyes on Mars? Well, the two spacecraft orbiting Mars, as part of the Mars Reconnaissance Orbiter or MRO, won’t be able to send in real time data. One will just be able to record the descent but not transmit in real time, and the other won’t be able to align itself till the last minute.

The descent is due on the 6th of August at 0131 EST or 0531 GMT. The place of descent will be a deep crater called the Gale Crater.

The Gale Crater is one of the lowest spots on Mars. If there is water underneath the surface, this is where the water will be closest to the surface.

Mission Aim

One of the most important aims of this mission is the search for water. There have been tell-tale signs of the existence of water, even if it was in prehistoric times. One of the best clues is the existence of clay and gypsum.

Now, the big question: Is there or was there life? Curiosity hopes to find out. Remember, water first, life later. And the search in the mission will also be conducted in the same way.

Why is NASA so worried about the landing?

NASA has reasons to be concerned about the landing. Curiosity tips the scales for spacecraft sent to foreign worlds at a massive one ton. It cannot be descended using landing bags which can cushion the fall. The plan is to deploy a parachute and also fire rockets in the opposite direction. This ‘descent platform’ will ensure smooth landing.

Best of luck NASA!

Curious about Curiosity? Keep following this blog.

Genetic Blueprint of Sperm Revealed

For the first time, scientists at Stanford University have sequenced single sperm cells.

But wait a minute, hasn’t human genome sequencing been going on for quite a while, now? And since all cells in our body have the same genome, what is the point of sperm cell sequencing?

Sperm Cells Are Half of a Normal Cell

Well, the answer is that almost all cells in our body have the same genome. All, except the reproductive cells. All non-reproductive cells in our body (called somatic cells) contain two copies of each chromosome, one from the father and one from the mother. Sperms (and egg cells from women) contain just one copy- the one that will be transmitted to the child. This halving of chromosomes in the reproductive cells is necessary to ensure that the child receives the right amount of genetic material.

Sons Have a Mosaic of Their Fathers’ DNA

During cell division in reproductive cells, the two chromosomes in a chromosome pair first interchange parts of each other in a process called recombination to produce two chromosomes that are a mosaic of the two parents. One of each mosaic pair then goes to the daughter sperm.

Here are shown two chromosomes of a chromosome pair (top). They undergo recombination to produce two mosaic chromosomes (middle). Each of these now go into one sperm (bottom). [Image Credit: regentsprep.org]
Sequencing will help shed light on this recombination process. Are there parts of the genome that are more susceptible to be recombined? What are the rates of mutation during this process? Mutation rates in humans are usually studied at a population level, this breakthrough will allow a closer look at the level of individual sperms by comparing the sperm DNA with the father’s.

Sequencing Single Cells on a Chip

To investigate these properties, researchers isolated sperm cells from a single semen sample. Individual cells are very hard to sequence because they have extremely small amounts of DNA. This experiment used a microfluidics chip to isolate 91 sperm cells from this sample and amplify each of their DNA (so they could generate enough DNA for the sequencing step). Each ‘sperm genome’ was then sequenced separately for a comparative analysis of their DNA.

Error in the recombination process has previously been linked to infertility and it is hoped that this could be a way to determine if the link is true, and if so, how. Adam Auton from the Albert Einstein College of Medicine in New York reckons the new technique could also be useful in studying cancer cells. “Every cancer is slightly different,” he says. If researchers can study single cells from a tumour, they may be able to get a better idea of which genes have been disrupted by mutations, and develop treatments to target them, he says.

Learning Mathematics From Dolphins

Dolphins might just be better than humans at mathematics. Researchers have found that these animals might process signals non-linearly to detect target prey.

Bottlenose dolphins use a unique strategy to capture fish, by making what are called ‘bubble nets’. They go around schools of fish in a wide circle in the sea, causing bubbles to spurt at the circumference of this circle. This alarms the fish, who all cluster together at the surface, right into the mouths of the waiting dolphin pack. What we don’t know is- how do these dolphins see their prey in these nets? Man-made SONAR systems cannot work in bubbly regions because the bubbles create a ‘fog’ that confound signals.

dolphins blowing bubbles
a) Dolphins herd sardines using bubble nets. b) A dolphin releases a cloud of bubbles using its blowhole. c) The bubble cloud expands, as the dolphin swims on and other dolphins join in d) The sardines are trapped in a wall of bubbles

[captioning via Leighton et al, 2012. Image Credit: The Blue Planet (BBC)]

 

 

Dolphins Have Inbuilt SONAR

Dolphins use echolocation by SONAR (Sound Navigation and Ranging) to detect their prey. They emit sound signals of a certain amplitude and frequency into the water, and use the reflected signals to detect the location of their surroundings, including prey. However, in the vicinity of these bubble nets, the bubbles create too much noise, leading scientists to wonder if the SONAR of dolphins can actually operate in bubble clouds or if dolphins actually ‘blind’ themselves in the process of creating these nets. Man-made SONAR systems which use linear signal processing have been unable to distinguish between bubbles and fish in these conditions.

Mathematicians at the University of Southampton have now used SONAR with non-linear signal processing to see if it can distinguish between fish and bubbles, and it can. Professor Leighton, who headed this research, said, “We know that dolphins emit sequences of clicks and the amplitude of each click can vary from one to the next, so that not all the clicks are the same loudness. We asked, what if this variation in amplitude was not coincidental, but instead was key to distinguishing fish from bubbles. ”

These clicks were shown to identify targets when processed using non-linear mathematics, raising the question of whether dolphins also benefit from such mathematics. The variation in amplitude of these clicks is the key: it produces changes in the echoes which can identify the target (fish) in the bubble net, where man-made sonar does not work. ”

However, in no way does this confirm that dolphins do use the same mechanism. This is simply a way by which they could process signals. In order to detect frequencies in bubble nets, dolphins would have to emit suitably low frequency signals in bubbly waters, and testing this would give an indication of whether non-linear processing is, in fact, how dolphins view their prey. This research could pave the way for new systems in detecting targets like sea mines in bubbly water. For now, it looks like dolphins as master mathematicians might just be the latest addition to the already rich tapestry of dolphin folklore.

More information about this research can be found here.

Stephen Hawking Trials Device Which Can Read His Mind

One of the greatest minds of the world is now lending his brain towards research. It will help him and, hopefully, many others. Stephen Hawking has agreed to undergo trials involving the development of new technology that literally can read your thoughts.

Reason to smile?

The new device, developed by Philip Low from Stanford University who is the founder of the healthcare company NeuroVigil, aims to monitor brain activity and then map it onto actual actions or speech. For example, if one is thinking of moving his paralysed right hand and grasp a cup kept to his side, the device can read that thought and attempt the action of grabbing at the cup.

Stephen Hawking, incapable of any sort of speech, now communicates with his cheek muscles. Specific movements of his cheek muscles signify certain words and these are then communicated to a speech device. Now, it seems that Hawking is losing control of even his cheek muscles and this is where this new portable device comes in handy.

Called the iBrain, it has to be ‘calibrated’, i.e. told what to do when a certain part of the brain is activated. The information is collected from one particular point on the scalp.

In a series of initial trials that Hawking has been involved in, he has been asked to imagine moving his hands or legs. He has also been asked to think specific thoughts and these have been recorded. It turns out that more than the specific brain activity, changes in brain activity is more important. The team is now working towards ‘converting’ these thoughts into action.

The device will also help Hawking think of words that can be written down after being fed to the system. The current process of constructing sentences, using a word one at a time, is painfully slow. This will be a much faster process.

Survivor, genius, and now, guinea pig – Stephen Hawking has been all of them. And is still living and telling us tales.