Tag Archives: science explained

At the Heart of All Matter

Large Hadron Collider at CERN

The hunt for the God particle by Joel Achenbach

Physics underwent one revolution after another. Einstein’s special theory of relativity (1905) begat the general theory of relativity (1915), and suddenly even such reliable concepts as absolute space and absolute time had been discarded in favor of a mind-boggling space-time fabric in which two events can never be said to be simultaneous. Matter bends space; space directs how matter moves. Light is both a particle and a wave. Energy and mass are inter- changeable. Reality is probabilistic and not deterministic: Einstein didn’t believe that God plays dice with the universe, but that became the scientific orthodoxy.

Most physicists believe that there must be a Higgs field that pervades all space; the Higgs particle would be the carrier of the field and would interact with other particles, sort of the way a Jedi knight in Star Wars is the carrier of the “force.” The Higgs is a crucial part of the standard model of particle physics—but no one’s ever found it.

The Higgs boson is presumed to be massive compared with most subatomic particles. It might have 100 to 200 times the mass of a proton. That’s why you need a huge collider to produce a Higgs—the more energy in the collision, the more massive the particles in the debris. But a jumbo particle like the Higgs would also be, like all oversize particles, unstable. It’s not the kind of particle that sticks around in a manner that we can detect—in a fraction of a fraction of a fraction of a second it will decay into other particles. What the LHC can do is create a tiny, compact wad of energy from which a Higgs might spark into existence long enough and vivaciously enough to be recognized.

Previous posts on CERN and the Higgs boson: The god of small thingsCERN Prepares for LHC OperationsCERN Pressure Test FailureThe New Yorker on CERN’s Large Hadron Collider

Your Inner Fish

photo of Neil Shubin

Your Inner Fish: A Journey into the 3.5-Billion-Year History of the Human Body by Neil Shubin. A great piece from the University of Chicago, Fish out of Water, provides a good preview to the book:

What are the leading causes of death in humans? Four of the top ten causes—heart disease, diabetes, obesity, and stroke – have some sort of genetic basis and, likely, a historical one. Much of the difficulty is almost certainly due to our having a body built for an active animal but the lifestyle of a spud.

The problem is that the brain stem originally controlled breathing in fish; it has been jerry-rigged to work in mammals… This works well in fish, but it is a lousy arrangement for mammals.

The example from microbes is not unique. Judging by the Nobel Prizes awarded in medicine and physiology in the past 13 years, I should have called this book Your Inner Fly, Your Inner Worm, or Your Inner Yeast. Pioneering research on flies won the 1995 Nobel Prize in medicine for uncovering a set of genes that builds bodies in humans and other animals. Nobels in medicine in 2002 and 2006 went to people who made significant advances in human genetics and health by studying an insignificant-looking little worm (C. elegans). Similarly, in 2001, elegant analyses of yeast (including baker’s yeast) and sea urchins won the Nobel in medicine for increasing our understanding of some of the basic biology of all cells. These are not esoteric discoveries made on obscure and unimportant creatures. These discoveries on yeast, flies, worms, and, yes, fish tell us about how our own bodies work, the causes of many of the diseases we suffer, and ways we can develop tools to make our lives longer and healthier.

Two of my more controversial posts have been: Evolution is Fundamental to Science and Understanding the Evolution of Human Beings by Country. Evolution is not controversial scientifically. Just as gravity is not. Obviously this understanding is far from universal however.

But it is just a matter of time: similar to Galileo Galilei and heliocentric cosmology. See: Galileo’s Battle for the HeavensCopernican SystemGalileo). We now sit maybe 100 years after Galileo’s death (based on the evidence available in support of each scientific theory). At some point the evidence is accepted and life continues. Though I must admit it, I find it a bit disappointing how long it is taking for some people to accept the evidence of evolution. But I probably need to learn to be more patient – I have been told that more than once. All I can do is try to help present some small amount of the great work so many scientists have done to advance our knowledge. And here I am talking about evolution – for the 28% of those in the USA that couldn’t provide the answer that earth revolves around the sun, in 1998, well, they need much more help than I can provide.

Science Explains: Flame Color

Have you ever wondered why some flames are yellow, while others are blue? Growing up, I was always told that it was a matter of temperature, that hot flames were blue and cooler flames were yellow. While there is a temperature difference, that difference is a “symptom” of what is going on, not the cause of the color difference.

Does that mean that there is solid stuff inside the candle flame? Let’s find out. Light the candle and be sure it is steady and won’t fall over. Hold the bottom of the plate in the candle flame for a few seconds. When you remove the plate, it has turned black!!! Don’t worry. You have not ruined it. Let it cool for a minute. Remember, it is HOT! Once it has cooled, rub your finger over the black spot. The black rubs off.

Related: Science Explained: What The Heck is a Virus?Why is the Sky Blue?Frozen Images

Really Old Coral – Over 2,000 Years Old

photo of sea coral (leiopathes_glaberrima)

Worlds oldest animal aged to 4000 years

deep-sea gold corals (Geradia sp.) and black corals (Leiopathes glaberrima, pictured left) indicate these animals live between two and four millennia

The new findings break all records previously claimed for marine invertebrates like the cold seep tubeworms (estimated 200 years old), quahog clams (estimated 400 years old), as well as the deep-sea wannabees Primnoa spp. and bamboo corals (45 – 300 years old). Given the new results, deep-sea animals can finally measure up to the longevity of the “Methuselah tree”, the Bristlecone Pine, estimated to be near 5000 years old.

perhaps the most important thing to mention is that gold and black corals are colonial zoantharians. No single polyp is thought to be this old, just the skeletal axis.

How is Coral an animal?

Coral is an animal that belongs to the phylum cnidaria…
During the mating season coral polyp release eggs and sperm into the water (picture below) and when an egg and a sperm meet they form a larva known as a planula…
The baby coral looks like a little tiny jellyfish and it floats around in the water until it finds a hard place to attach to, usually a coral reef. Then it lands and starts to build itself a shell. It builds it by combining carbon dioxide (CO2) and calcium (Ca) in the water to make calcium carbonate (CaCO3) also known as limestone. This shell is shaped like a round vase and the coral polyp lives inside…

Related: South Pacific to Stop Bottom-trawlingBatfish Key to Keeping Reefs CleanBdelloid Rotifers Abandoned Sex 100 Million Years Ago

The World’s Hottest Chili

The World’s Hottest Chili:

The standard measure for such things is the Scoville Heat Unit, or SHU, named after Wilbur Lincoln Scoville, a chemist who in 1912 developed a method of assessing the heat given off by capsaicin, the active ingredient in chili peppers. Jalapeño peppers measure about 5,000 SHUs. The bhut jolokia tops a million.

Food scientists speculate that hot chilies have an unexpected side effect that boosts their popularity. A publication of the Brooklyn Botanical Garden in New York described it this way: “When capsaicin comes into contact with the nerve endings in the tongue and mouth, pain messengers, called neurotransmitters, are sent to the brain in a panic. The brain, mistakenly perceiving that the body is in big trouble, responds by turning on the waterworks to douse the flames. The mouth salivates, the nose runs and the upper body breaks into a sweat. The heart beats faster and the natural painkiller endorphin is secreted. In other words, you get a buzz.”

Related: Frozen ImagesEat food. Not too much. Mostly plants.

20 Things You Didn’t Know About Snow

20 Things You Didn’t Know About Snow by Susan Kruglinski

1 Snow is a mineral, just like diamonds and salt
5 At the center of almost every snow crystal is a tiny mote of dust, which can be anything from volcanic ash to a particle from outer space.
7 Freshly fallen snow is typically 90 to 95 percent air, which is what makes it such a good thermal insulator.

Related: National Snow and Ice Data Center FAQWhat Are Viruses?Science Explains How10 Science Facts You Should Know

DNA Seen Through the Eyes of a Coder

Great paper looking at DNA from the perspective of a computer programmer. DNA seen through the eyes of a coder by Bert Hubert:

The language of DNA is digital, but not binary. Where binary encoding has 0 and 1 to work with (2 – hence the ‘bi’nary), DNA has 4 positions, T, C, G and A. Whereas a digital byte is mostly 8 binary digits, a DNA ‘byte’ (called a ‘codon’) has three digits. Because each digit can have 4 values instead of 2, an DNA codon has 64 possible values, compared to a binary byte which has 256.

A typical example of a DNA codon is ‘GCC’, which encodes the amino acid Alanine. A larger number of these amino acids combined are called a ‘polypeptide’ or ‘protein’, and these are chemically active in making a living being.

Furthermore, 97% of your DNA is commented out. DNA is linear and read from start to end. The parts that should not be decoded are marked very clearly, much like C comments. The 3% that is used directly form the so called ‘exons’. The comments, that come ‘inbetween’ are called ‘introns’.

Related: RNA Interference WebcastHiring Software DevelopersDonald Knuth, Computer Scientist

Science Explained: What The Heck is a Virus?

What The Heck is a Virus? [removed broken link]

A virus is not strictly alive.. nor is it strictly dead… A virus has some fundamental information (genes made of DNA or RNA) which allows it to make copies of itself. However, the virus must be inside a living cell of some kind before the information can be used. In fact, the information won’t be made available unless the virus enters a living cell. It is this entrance of a virus into a cell which is called a viral infection. Too, the virus is very, very small relative to the size of a living cell. Therefore, the information the virus can carry is actually not enough to allow it to make copies (replicate). The virus uses the cell’s machinery and some of the cell’s enzymes to generate virus parts which are later assembled into thousands of new, mature, infectious virus which can leave the cell to infect other cells.

Related: What Are Viruses?Science Summary: PhotosynthesisAmazing Science: RetrovirusesUsing Bacteria to Carry Nanoparticles Into Cells

Amazing Science: Retroviruses

One of the great things about writing this blog is I find myself more focused on reading about interesting science. Retroviruses are very interesting and frankly amazing. Darwin’s Surprise by Michael Specter, The New Yorker:

A retrovirus stores its genetic information in a single-stranded molecule of RNA, instead of the more common double-stranded DNA. When it infects a cell, the virus deploys a special enzyme, called reverse transcriptase, that enables it to copy itself and then paste its own genes into the new cell’s DNA. It then becomes part of that cell forever; when the cell divides, the virus goes with it. Scientists have long suspected that if a retrovirus happens to infect a human sperm cell or egg, which is rare, and if that embryo survives – which is rarer still – the retrovirus could take its place in the blueprint of our species, passed from mother to child, and from one generation to the next, much like a gene for eye color or asthma.

When the sequence of the human genome was fully mapped, in 2003, researchers also discovered something they had not anticipated: our bodies are littered with the shards of such retroviruses, fragments of the chemical code from which all genetic material is made. It takes less than two per cent of our genome to create all the proteins necessary for us to live. Eight per cent, however, is composed of broken and disabled retroviruses, which, millions of years ago, managed to embed themselves in the DNA of our ancestors. They are called endogenous retroviruses, because once they infect the DNA of a species they become part of that species. One by one, though, after molecular battles that raged for thousands of generations, they have been defeated by evolution. Like dinosaur bones, these viral fragments are fossils. Instead of having been buried in sand, they reside within each of us, carrying a record that goes back millions of years. Because they no longer seem to serve a purpose or cause harm, these remnants have often been referred to as “junk DNA.” Many still manage to generate proteins, but scientists have never found one that functions properly in humans or that could make us sick.

How amazing is that? I mean really think about it: it is incredible. The whole article is great. Related: Old Viruses Resurrected Through DNADNA for once species found in another species’ GenesNew Understanding of Human DNARetrovirus overview (Tulane)Cancer-Killing Virus
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Why is the Sky Blue?

Here is a a nice post explaining why we see blue when we look at the sky, Why Is The Sky Blue?:

Most of the atmospheric gases are transparent to visible light. They don’t filter the Sun’s light and make it yellow, as a yellow filter would. Besides, if colored gases made the Sun appear yellow, where does the blue come from? The part of the atmosphere that changes the Sun’s light is the molecules and tiny particles that are floating in it.

There are particles of water–tiny droplets too small to be seen as clouds. There are particles of organic material–smog or haze, condensed from volatile organic chemicals that have gotten into the air. There are particles of sulfuric acid from volcanoes and power plants. There are molecules of gases in the atmosphere.

These tiny particles, much smaller than the wavelengths of sunlight, scatter the sunlight as photons from the Sun interact with the particles. This is called Rayleigh scattering after the British physicist who described how it works. (Larger particles, like the water droplets in clouds, are closer to the wavelengths of sunlight, and they scatter it differently. This is why clouds are not blue.)

Science explained – quick overviews of scientific concepts: How Does That Happen? Science Provides the AnswerIncredible Insects10 Science Facts You Should KnowWhat Everyone Should LearnScience Summary: PhotosynthesisString Theory in 1 pageHow do antibiotics kill bacteria?