Category Archives: Science

MicroRNAs Emerged Early in Evolution

New Research Shows MicroRNAs Emerged Early in Evolution

“MicroRNAs have been available to regulate and shape gene expression as far back as we can go in animal evolution—they might even predate animals,” says Bartel, a leader in the discovery and functional study of microRNAs. “They might have helped to usher in the era of multi-cellular animal life.”

First discovered in 1993, microRNAs are strands of RNA that are 21-24 nucleotides in length. They dampen gene expression by intercepting messenger RNA before it can turn the cellular crank that translates a gene into a protein. Earlier, Bartel’s research team showed that each microRNA can regulate the expression of hundreds of genes.

The ability of microRNAs to silence gene expression likely evolved from a more ancient defense against viruses, bacteria, and other mobile genetic elements that can mutate host DNA.
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The scientists determined that the starlet sea anemone has both microRNAs and piRNAs. In addition, the anemone makes proteins resembling those that interact with these small RNAs in humans. Both types of small RNA were also found in the sponge. The third target of their search, Trichoplax, did not contain any microRNAs, though Bartel suspects they may have existed in ancestral forms and later disappeared.

New Neurons are Needed for New Memories

New neurons are needed for new memories

Around 15 years ago, researchers discovered that the adult rodent brain contains discrete populations of stem cells which continue to divide and produce new cells throughout life. This discovery was an important one, as it overturned a persistent dogma in neuroscience which held that the adult mammalian brain cannot regenerate.
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This study shows that inhibiting neurogenesis has strikingly different consequences in two distinct regions of the brain. In the olfactory bulb, it leads to significant shrinkage but apparently does not alter smell-related behaviour. In the hippocampus, the effect on structure is not so marked, but it is clear that newly-generated neurons are necessary for the processes of learning and memory. Exactly how the new cells contribute to memory formation is still unknown.

More interesting stuff. Related: How The Brain Rewires Itself – Scientists Witness the Birth of a Brain Cell – New Neurons in Old Brains – No Sleep, No New Brain Cells

Foreign Cells Outnumber Human Cells in Our Bodies

This is one of those area I find very interesting: People Have More Bacterial Cells than Human Cells. Colin Nickerson has written an interesting article on the topic: Of microbes and men

Scientists estimate that 90 percent of the cells contained in the human body belong to nonhuman organisms – mostly bacteria, but also a smattering of fungi and other eensy entities. Some 100 trillion microbes nestle in niches from our teeth to our toes.

But what’s setting science on its heels these days is not the boggling numbers of bugs so much as the budding recognition that they are much more than casual hitchhikers capable of causing disease. They may be so essential to well-being that humans couldn’t live without them.

In this emerging view, humans and their microbes – or, as some biologists playfully put it, microbes and their attached humans – have evolved together to form an extraordinarily complex ecosystem.

The understanding of the complex interaction is something I came to through reading on the overuse of antibiotics. And the more I read the more interesting it gets.

“We can’t take nutrition properly without bacteria. We can’t fight bad germs without good germs,” he said. “It may turn out that secretions from bacteria affect not only long-term health, but hour-by-hour moods – could a person’s happiness depend on his or her bugs? It’s possible. Our existences are so incredibly intertwined.”

However, in the opinion of some researchers, this strange union may be headed for trouble because of profligate use of antibiotics and antiseptic lifestyles that deter the transfer of vital strains of bacteria that have swarmed in our systems at least since early humans ventured out of Africa.

More Mysterious Space Phenomenon

One of the things I really hope this blog helps accomplish is to show how science progresses (which explains why I use that tag so often, 3rd most, other popular tags: animals (most used), engineers 2nd, fun and webcasts tied for 4th).

Science is a process of continual learning as curiosity leads us to seek better understanding. On a small scale this can mean a person learning more about knowledge already understood by others. But it also means the scientific community facing new questions and coming up with new explanations for the new questions raised by observations (and testing those new explanations…). Mysterious New ‘Dark Flow’ Discovered in Space

Patches of matter in the universe seem to be moving at very high speeds and in a uniform direction that can’t be explained by any of the known gravitational forces in the observable universe. Astronomers are calling the phenomenon “dark flow.” The stuff that’s pulling this matter must be outside the observable universe, researchers conclude.
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They discovered that the clusters were moving nearly 2 million mph (3.2 million kph) toward a region in the sky between the constellations of Centaurus and Vela. This motion is different from the outward expansion of the universe (which is accelerated by the force called dark energy).

“We found a very significant velocity, and furthermore, this velocity does not decrease with distance, as far as we can measure,” Kashlinsky told SPACE.com. “The matter in the observable universe just cannot produce the flow we measure.”

Incident in LHC Sector 34

Incident in LHC sector 34

During commissioning (without beam) of the final LHC sector (sector 34) at high current for operation at 5 TeV, an incident occurred at mid-day on Friday 19 September resulting in a large helium leak into the tunnel. Preliminary investigations indicate that the most likely cause of the problem was a faulty electrical connection between two magnets, which probably melted at high current leading to mechanical failure. CERN ’s strict safety regulations ensured that at no time was there any risk to people.

A full investigation is underway, but it is already clear that the sector will have to be warmed up for repairs to take place. This implies a minimum of two months down time for LHC operation. For the same fault, not uncommon in a normally conducting machine, the repair time would be a matter of days.

Mars Rover Continues Exploration

Mars Rover

Ageing Mars rover to embark on epic two-year journey

The ageing but intrepid Mars rover Opportunity is set to embark on a two-year mission it may never complete – a seven-mile journey to a crater far bigger than one it has called home for two years, NASA have revealed.

The golf-cart-sized robot with a wobbly front wheel climbed out of Victoria crater earlier this month and scientists at NASA’s Jet Propulsion Laboratory in California are steering the probe toward a crater more than 20 times larger, dubbed Endeavor.
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There are also small rocks strewn about the surface on the route, which appear to have been dug up by meteor impacts farther away. This will give scientists the chance to examine material that otherwise would be too deep to reach. Opportunity still has the use of all six of its wheels, though the right front wheel can no longer be steered.

15 Photovoltaics Solar Power Innovations

15 Photovoltaics Solar Power Innovations You Must See

Researchers at McMaster University (coolest name ever) have succeeded in ‘growing’ light-absorbing nanowires made of high-performance photovoltaic materials on carbon-nanotube fabric. In other words, hairy solar panels.

The aim is to produce flexible, affordable solar cells that, within five years, will achieve a conversion efficiency of 20%. Longer term, it’s theoretically possible to achieve 40% efficiency!
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while looking for a solution, researchers noticed that moths have very non-reflective eyes (“most likely an evolutionary defense against nocturnal predators”). The moth-eye process creates panels that reflect less than 2% of light. That’s a vast improvement over the 35 to 40% reflection rate seen without the anti-reflection coating layers.
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Some experts are speculating that First Solar might beat over 80 competitors to achieve manufacturing costs low enough to market solar panels at less than $1 per Watt, the target considered necessary for solar to compete with coal-burning electricity on the grid.

Asymmetrical Brains Aid Multi-tasking

Asymmetrical brains help fish (and us) to multi-task:

In the animal world, the ability to multi-task is a matter of life and death. Many species must be ever-watchful for food, while simultaneously looking out for predators who would view them in the same way Like too many open applications that slow down a computer, these multiple tasks compete for the brain’s finite resources. Those who survive life’s challenges are those with an edge at efficiently dealing with multiple demands.

One way of doing this is to use parallel processing – to delegate different parts of a problem to different pieces of hardware. This is exactly the situation found in the human brain, with two asymmetric hemispheres associated with different mental abilities. And this ‘lateralisation’ is not unique to us, but seems to be present in all back-boned animals, from fish to apes. An explanation for this asymmetry now becomes obvious – it may allow animals to multi-task, acting as a sort of cerebral division of labour.
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In these cases, regardless of parallel processing power, an asymmetric brain is clearly a disadvantage. The two scientists believe that the tipping point between these pros and cons comes when an animal has to perform difficult mental tasks.

Other studies have shown that asymmetrical brains endow wild chimpanzees with superior termite-fishing skills, and (equally wild) human children with better mathematical and verbal abilities than their classmates. It may be that over the course of evolution, our brain’s halves started to work together more effectively as they became more different and specialised. It is ironic and sad then, that the opposite seems to hold true for the divergence of human cultures.

Church of England Sees Wisdom in Understanding Evolution

Good religion needs good science by Rev Dr Malcolm Brown, Director of Mission and Public Affairs

When a big new idea emerges which changes the way people look at the world, it’s easy to feel that every old idea, every certainty, is under attack and then to do battle against the new insights. The church made that mistake with Galileo’s astronomy, and has since realised its error. Some church people did it again in the 1860s with Charles Darwin’s theory of natural selection.
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Subsequent generations have built on Darwin’s work but have not significantly undermined his fundamental theory of natural selection. There is nothing here that contradicts Christian teaching. Jesus himself invited people to observe the world around them and to reason from what they saw to an understanding of the nature of God (Matthew 6: 25–33). Christian theologians throughout the centuries have sought knowledge of the world and knowledge of God. For Thomas Aquinas there was no such thing as science versus religion; both existed in the same sphere and to the same end, the glory of God.
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Charles Darwin: 200 years from your birth, the Church of England owes you an apology for misunderstanding you and, by getting our first reaction wrong, encouraging others to misunderstand you still. We try to practice the old virtues of ‘faith seeking understanding’ and hope that makes some amends. But the struggle for your reputation is not over yet, and the problem is not just your religious opponents but those who falsely claim you in support of their own interests. Good religion needs to work constructively with good science – and I dare to suggest that the opposite may be true as well.

Tardigrades In Space (TARDIS)

Research showing that Tardigrades (Water Bears) can survive in space without protection has been in the news lately. There is a blog with a few posts from the research team (only from last year unfortunately): Tardigrades In Space (TARDIS). They chose not to publish the research in an open access fashion, unfortunately.

Tiny Critters Survive Space

These small, segmented animals not only survived a 12-day orbital expedition, some members of the community felled by solar radiation actually recovered upon their return to Earth.

“How these animals were capable of reviving their body … remains a mystery,” said lead researcher Ingemar JÃ¶nsson, with Sweden’s Kristianstad University, who writes about the discovery in this week’s issue of Current Biology.
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Most of the 3,000 creatures not only survived, but they went on to reproduce once they came back to Earth. About 12 percent of the animals exposed to ultraviolet radiation revived after being put back in water, a puzzling find since researchers presume the sterilizing rays broke down the tardigrades’ DNA. “This type of radiation cuts the DNA strand effectively in most organisms”