Category Archives: Science

Popular Curious Cat Science and Engineering Blog Posts

Here I include a list of some of the most popular posts from my blog in the last year. I hope you enjoy them. Only one post was written in 2011. Many of my older posts are consistently popular, while some have huge spikes for a day or two when they are popular on some social site (Reddit, Facebook, Twitter, Google+…). For posts that get huge spikes it isn’t uncommon for that pattern to repeat occasionally. I must have been doing something right in 2008 (based on how many of my popular post are from 2008). I’ll try to repeat that in 2012.

Photo of kids intently studying on a Malaysian beach

My mom with a group of Malaysia kids apparently intent on learning something. I am there, but not visible in this photo. Photo by my father.

Memory is Stored by Turning on Genes in Neurons (to Alter Connection Between Neurons)

I find these kind of stories so interesting. I really have so little understanding of genes. I knew memory had something to do with altering connections between neurons. I had no idea that required turning on many genes in those neurons. Life really is amazing.

Neuroscientists identify a master controller of memory

When you experience a new event, your brain encodes a memory of it by altering the connections between neurons. This requires turning on many genes in those neurons.

Lin and her colleagues found that Npas4 turns on a series of other genes that modify the brain’s internal wiring by adjusting the strength of synapses, or connections between neurons. “This is a gene that can connect from experience to the eventual changing of the circuit,” says [Yingxi] Lin

So far, the researchers have identified only a few of the genes regulated by Npas4, but they suspect there could be hundreds more. Npas4 is a transcription factor, meaning it controls the copying of other genes into messenger RNA — the genetic material that carries protein-building instructions from the nucleus to the rest of the cell. The MIT experiments showed that Npas4 binds to the activation sites of specific genes and directs an enzyme called RNA polymerase II to start copying them.

“Npas4 is providing this instructive signal,” Ramamoorthi says. “It’s telling the polymerase to land at certain genes, and without it, the polymerase doesn’t know where to go. It’s just floating around in the nucleus.”

When the researchers knocked out the gene for Npas4, they found that mice could not remember their fearful conditioning. They also found that this effect could be produced by knocking out the gene just in the CA3 region of the hippocampus. Knocking it out in other parts of the hippocampus, however, had no effect.

One of the things I aim to do in 2012 is read a few more books on biology and genes. I find it incredible what are genes actually are doing to allow us to live our lives. And I am also very ignorant on the whole area. So hopefully I can have some fun next year learning about it.

Related: Epigenetic Effects on DNA from Living Conditions in Childhood Persist Well Into Middle AgeAntigen Shift in Influenza Viruses8 Percent of the Human Genome is Old Virus GenesBrain Reorganizes As It Learns Math

Brian Cox – Lecture on Science and Quantum Mechanics

Brian Cox gave a wonderful lecture at the Royal Institution of Great Britain. This is one more great thing the internet makes possible: have great fun while you learn. Enjoy.

With the help of Jonathan Ross, Simon Pegg, Sarah Millican and James May, Brian shows how diamonds – the hardest material in nature – are made up of nothingness; how things can be in an infinite number of places at once; why everything we see or touch in the universe exists; and how a diamond in the heart of London is in communication with the largest diamond in the cosmos.

Related: Quantum Mechanics Made Relatively Simple Podcasts by Hana BetheBrian Cox Particle Physics WebcastPhysicists Observe New Property of Matter

Christian Science Monitor Scientific Literacy Quiz

This is a nice science quiz that you should learn from while taking it (unless you are extremely knowledgeable already and know every answer).

It is multiple choice, and even on some I got right, I wasn’t completely sure between two choices for example (What is the heaviest noble gas?). I managed to guess pretty well but also missed a couple.

It has one hugely annoying usability failure: after answering the question it loads a new page with the right answer and you have to click again to get the next question. Doing this for 50 questions is extremely tiresome and pointless. They correct answer could be shown at the top and also show the next question.

Some questions in the quiz:

  1. Newton’s First Law of Motion describes what phenomenon?
  2. What word, which comes from a Greek term meaning “good kernel,” describes an organism whose cells contain chromosomes inside a nucleus bounded by a membrane, as distinguished from bacterial forms of life?
  3. DNA contains adenine, cytosine, guanine, and what other nucleotide base, which is not found in RNA? (I had no idea on this one)
  4. What term describes the single initial cell of a new organism that has been produced by means of sexual reproduction?
  5. What term for an elementary particle and a fundamental constituent of matter gets its name from a line in James Joyce’s 1939 novel “Finnegans Wake”?

I managed to get 39 right, which honestly include lots of educated guesses and lucky guesses. It almost seemed the test was 30% on your ability to translate Greek or Latin. Overall I think it was difficult and I was lucky to get 39 right. It would be nice to show participant results like an earlier Science Knowledge Quiz did. Percentage getting each question would be interesting too, along with the distribution of answers.

They do provide all your answers (and the correct answers) on one page once you finish (with is a nice usability touch).

Related: Nearly Half of Adults in the USA Don’t Know How Long it Takes the Earth to Circle the SunTen Things Everyone Should Know About ScienceUnderstanding the Evolution of Human Beings by Country

Can Just A Few Minute of Exercise a Day Prevent Diabetes?

That just 1 minute of exercise a day could help prevent diabetes seems to good to be true. But research at the University of Bath indicates it might be true. I am a bit of a soft touch for seeing the benefits of exercise. And I also love health care that focuses on achieving healthy lives instead of what most of the spending focuses on: treating illness.

Performing short cycle sprints three times a week could be enough to prevent and possibly treat Type 2 diabetes researchers at the University of Bath believe.

Volunteers were asked to perform two 20-second cycle sprints, three times per week (but really this works out to under 10 minutes of total time including warm up). After six weeks researchers saw a 28% improvement in their insulin function. Type 2 diabetes occurs when blood sugar levels build up to dangerously high levels due to reduced insulin function, often caused by a sedentary lifestyle. The condition can cause life-threatening complications to the heart, kidneys, eyes and limbs, and has huge costs (monetarily and to people’s lives).

Regular exercise can help keep blood sugar levels low but busy lifestyles and lack of motivation mean 66% of the population is not getting the recommended five 30-minute sessions of moderate exercise a week.

Dr Niels Vollaard who is leading the study, said: “Our muscles have sugar stores, called glycogen, for use during exercise. To restock these after exercise the muscle needs to take up sugar from the blood. In inactive people there is less need for the muscles to do this, which can lead to poor sensitivity to insulin, high blood sugar levels, and eventually type 2 diabetes… We already knew that very intense sprint training can improve insulin sensitivity but we wanted to see if the exercise sessions could be made easier and shorter.”

In the study the resistance on the exercise bikes could be rapidly increased so volunteers were able to briefly exercise at much higher intensities than they would otherwise be able to achieve. With an undemanding warm-up and cool-down the total time of each session was only 10 minutes.

This type of study is very helpful in identifying solutions that will allow more people to lead healthy lives and save our economies large amount of money. Medical studies can’t be accepted on face value. They are often not confirmed by future studies and therefore it is unwise to rely on the results of 1 study. The results provide interesting information but need to be confirmed (and in the area of studies on human health this has been shown to be problematic – are health is quite a tricky area to study).

Related: Aerobic Exercise Plus Resistance Training Helps Control Type 2 DiabetesRegular Exercise Reduces FatigueFood Rules: An Eater’s Manual

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Using a Virus to Improve Solar-cell Efficiency Over 30%

Solar and wind energy are making great strides, and are already contributing significantly to providing relatively clean energy.

Researchers at MIT have found a way to make significant improvements to the power-conversion efficiency of solar cells by enlisting the services of tiny viruses to perform detailed assembly work at the microscopic level.

In a solar cell, sunlight hits a light-harvesting material, causing it to release electrons that can be harnessed to produce an electric current. The research, is based on findings that carbon nanotubes — microscopic, hollow cylinders of pure carbon — can enhance the efficiency of electron collection from a solar cell’s surface.

Previous attempts to use the nanotubes, however, had been thwarted by two problems. First, the making of carbon nanotubes generally produces a mix of two types, some of which act as semiconductors (sometimes allowing an electric current to flow, sometimes not) or metals (which act like wires, allowing current to flow easily). The new research, for the first time, showed that the effects of these two types tend to be different, because the semiconducting nanotubes can enhance the performance of solar cells, but the metallic ones have the opposite effect. Second, nanotubes tend to clump together, which reduces their effectiveness.

And that’s where viruses come to the rescue. Graduate students Xiangnan Dang and Hyunjung Yi — working with Angela Belcher, the W. M. Keck Professor of Energy, and several other researchers — found that a genetically engineered version of a virus called M13, which normally infects bacteria, can be used to control the arrangement of the nanotubes on a surface, keeping the tubes separate so they can’t short out the circuits, and keeping the tubes apart so they don’t clump.

The system the researchers tested used a type of solar cell known as dye-sensitized solar cells, a lightweight and inexpensive type where the active layer is composed of titanium dioxide, rather than the silicon used in conventional solar cells. But the same technique could be applied to other types as well, including quantum-dot and organic solar cells, the researchers say. In their tests, adding the virus-built structures enhanced the power conversion efficiency to 10.6% from 8% — almost a one-third improvement.

Read the full press release

Related: Using Virus to Build BatteriesUsing Viruses to Construct ElectrodesUsing Bacteria to Carry Nanoparticles Into Cells

Rats Show Empathy-driven Behavior

Rats free trapped companions, even when given choice of chocolate instead

The experiments, designed by psychology graduate student and first author Inbal Ben-Ami Bartal with co-authors Decety and Peggy Mason, placed two rats that normally share a cage into a special test arena. One rat was held in a restrainer device — a closed tube with a door that can be nudged open from the outside. The second rat roamed free in the cage around the restrainer, able to see and hear the trapped cagemate but not required to take action.

The researchers observed that the free rat acted more agitated when its cagemate was restrained, compared to its activity when the rat was placed in a cage with an empty restrainer. This response offered evidence of an “emotional contagion,” a frequently observed phenomenon in humans and animals in which a subject shares in the fear, distress or even pain suffered by another subject.

While emotional contagion is the simplest form of empathy, the rats’ subsequent actions clearly comprised active helping behavior, a far more complex expression of empathy. After several daily restraint sessions, the free rat learned how to open the restrainer door and free its cagemate. Though slow to act at first, once the rat discovered the ability to free its companion, it would take action almost immediately upon placement in the test arena.

“We are not training these rats in any way,” Bartal said. “These rats are learning because they are motivated by something internal. We’re not showing them how to open the door, they don’t get any previous exposure on opening the door, and it’s hard to open the door. But they keep trying and trying, and it eventually works.”

To control for motivations other than empathy that would lead the rat to free its companion, the researchers conducted further experiments. When a stuffed toy rat was placed in the restrainer, the free rat did not open the door. When opening the restrainer door released his companion into a separate compartment, the free rat continued to nudge open the door, ruling out the reward of social interaction as motivation. The experiments left behavior motivated by empathy as the simplest explanation for the rats’ behavior.

“There was no other reason to take this action, except to terminate the distress of the trapped rats,” Bartal said. “In the rat model world, seeing the same behavior repeated over and over basically means that this action is rewarding to the rat.”

As a test of the power of this reward, another experiment was designed to give the free rats a choice: free their companion or feast on chocolate. Two restrainers were placed in the cage with the rat, one containing the cagemate, another containing a pile of chocolate chips. Though the free rat had the option of eating all the chocolate before freeing its companion, the rat was equally likely to open the restrainer containing the cagemate before opening the chocolate container.

“That was very compelling,” said Mason, Professor in Neurobiology. “It said to us that essentially helping their cagemate is on a par with chocolate. He can hog the entire chocolate stash if he wanted to, and he does not. We were shocked.”

Now that this model of empathic behavior has been established, the researchers are carrying out additional experiments. Because not every rat learned to open the door and free its companion, studies can compare these individuals to look for the biological source of these behavioral differences. Early results suggested that females were more likely to become door openers than males, perhaps reflecting the important role of empathy in motherhood and providing another avenue for study…

Interesting study. My guess is this is the kind of thing those that don’t like science would deride. I believe in the value of science. I believe in the value of learning. I believe that such experiments are what drives science forward. I believe if you want your economy to benefit from investing in science you should be encouraging hundreds and thousands of such experiments. Funding for this study was provided by The National Science Foundation (NSF), and others.

I am thankful that more and more countries are willing to invest in science, especially since the USA is showing an increasing anti-science attitude. I would rather the USA continue to believe in the value of science and other countries looked to increase investments. But, it is much better that other countries increase their interest in science, and willingness to invest in science, to more than make up for the USA’s decisions to reduce the appreciation for science than for the world to just lose do to a decrease in investments in science.

Related: Insightful Problem Solving in an Asian ElephantPigeon Solves Box and Banana ProblemStand with ScienceEliminating NSF Program to Aid K-12 Science EducationThe Importance of Science Education

Stand with Science – Late is Better than Never

The USA public has made very bad decisions in who to send to Washington DC to spend our money (and the money of our children and grandchildren). We have wasted hundreds of billions that could have been spent more wisely. I happen to think investing in science and engineering is important for a societies economic health. The problem the USA has is we have chosen to waste lots of money for decades, at some point you run out of money (yes the USA government doesn’t really, as they can print it, but essentially they do – in practical terms).

I would certainly eliminate tax breaks for trust fund babies and trust fund grandchildren (while your grandchildren are going to be left holding the bag for the spending those elected by us, the grandchildren of the rich often get huge trust funds with no taxes being paid at all). But most of the people we have elected want to give trust fund babies huge payoffs. I would cut much spending in government – spending 5% less in 2020 than we did this year would be fine with me. But we don’t elect people that support that. I would support not adding new extensions to tax cuts sold with false claims and again supported by those we continue to elect. I wouldn’t allow the financial industry subverting of markets. But again we elect people that do allow that. And when the bill comes due for letting them take tens and hundreds of millions in individual profits in the good years, we can either let the economy go into a depression (maybe) or spend hundreds of billions to trillions bailing out those institutions our politicians let threaten the economy.

It might not seem fair, but there are consequences to allowing our political system to waste huge amounts of money paying of special interests for decades. And investing in science and engineering has been a casualty and will likely continue to be. Eventually you run out of money, even for the stuff that matters. Trying to fight for politicians that will put the interests of the country ahead of their donors is not something you can do effectively only when your interests are directly threatened. At that point things may already be too bad to be saved.

I have been writing about the failed political system for quite awhile now. I wrote awhile back that Hillary Clinton’s idea to tripple the number of GRFP awards was something I thought was very smart economically. But even then I questioned if we could afford it, if we refused to do anything else different (just adding new spending isn’t what the country needed).

Even in the state the politicians we continue to elect (we elect the same people election after election – there is no confusion about what they will do) we can debate what to cut and for something we spend so little on as investing science and engineering we can even easily increase that spending and not have any real impact on cutting overall spending. But those we have elected don’t show much interest in investing in science and engineering overall.

The USA continues to invest a good deal in science and engineering. But the difference in focus today versus the 1960’s is dramatic. The USA will continue to do well in the realm of science. The advantages gained over decades leave us in a hugely beneficial position – and one that takes other countries decades to catch up to. Now some countries have been working on that for decades now, and are doing very well. China, hasn’t been at it quite as long but has been making amazingly fast progress (similar to the amazing economic story).

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Friday Fun: Octopus Walks on Land

Just a fun video for your Friday. Octopuses are really very cool. Not quite as cool as cats but way up there in the realm of cool animals. Octopuses, octopi and octopodes are all acceptable words for plural of octopus?

A few year ago (2008) I posted about another very cool octopus, who liked to juggling fellow aquarium occupants.

I think I will devote more time to learning about octopuses and posting more about them.

Related: Hydromedusae, Siphonophora, Cnidarians, CtenophoresCritter Cam: Sea Lion versus OctopusRed octopus at a brine lake beneath the sea

YouTube SpaceLab Experiment Competition

YouTube SpaceLab is an open competition inviting 14 – 18 year olds (anywhere in the world) to create an idea for a science experiment in space. You don’t have to actually do the experiment, you just have to record yourself explaining it.

Entries must have be submitted on YouTube by 07:59 GMT on December 8th.

The winning experiments will be conducted on the International Space Station (ISS) and beamed live on YouTube for the whole planet to see.

Winners get the choice to either watch the rocket blast off with your idea on it in Japan or take a specially tailored astronaut training course in Russia when you turn 18. There are other amazing prizes for the runners-up too.

Here is an example entry from 3 students in UK on an experiment to learn about quorum sensing by bacteria in the micro gravity of space.

Related: Google Science Fair 2011 ProjectsBacteria Communicate Using a Chemical Language (quorum sensing)11 Year Old Using Design of ExperimentsResearch by group of 8 to 10 Year Olds Published in Royal Society Journal