Tag Archives: science explained

Photosynthesis: Science Explained

Another very good webcast on a science topic from Crash Course. It is packed with info, thankfully you can pause and rewind as much as you need. Well normally you can, YouTube decided to not let me do that just now 🙁

Star Stuff: The Universe is In Us

Great statement from Neil DeGrasse Tyson on “what is the most astounding fact you can share with us about the universe.”

“The atoms that comprise life on earth, the atoms that make up the human body, are traceable to the crucibles that cooked light elements into heavy elements in their core under extreme temperatures and pressures. These stars, the high mass ones among them, went unstable in their later years. They collapsed and then exploded scattering their enriched guts across the galaxy. Guts made of carbon, nitrogen, oxygen, and all the fundamental ingredients of life itself. These ingredients become part of gas clouds that condense, collapse, form the next generation of solar systems: stars with orbiting planets. And those planets now have the ingredients for life itself. So when I look up at the night sky and I know that, yes we are part of this universe, we are in this universe, but perhaps more important than both of those facts, is that the universe is in us… my atoms came from those stars….”

I think this might well be my thought on the most astounding fact also. Ever since I learned the atoms we are made of were created inside stars it has never ceased to amaze me.

Neil DeGrasse Tyson is amazing. I would edit his statement a bit myself, though, to make it:

“The most astounding fact is that the atoms that comprise life on earth, the atoms that make up the human body, were created in the crucible of stars that cooked light elements into heavy elements. Those stars went unstable, in their later years: they collapsed and then explored scattering their enriched cores across the galaxy. Those stars made the carbon, nitrogen, oxygen, and all the fundamental ingredients of life itself. Those ingredients became part of gas clouds that condensed to form the next generation of solar systems: stars with orbiting planets. And those planets have the ingredients for life. So when I look up at the night sky, I know that my atoms came from the predecessors of the stars I see.”

Exploring Eukaryotic Cells

This webcast is packed with information on the makeup and function of eukaryotic cells, which are the type of cells found in animals. It is part of a interesting series of science webcasts by Crash Course. The webcast style might be a bit too hyperactive and flippant for some but the content is quite interesting and the videos they are are of similar style and quality so if you like this one you can subscribe to their channel. They offer quite a few webcasts on science but they also offer webcasts on history.

Cool Animation of a Virus Invading a Person’s Body

Flu Attack! How A Virus Invades Your Body

First, some new viruses get caught in mucus and other fluids inside your body and are destroyed. Other viruses get expelled in coughs and sneezes. Second, lots of those new viruses are lemons. They don’t work that well. Some don’t have the right “keys” to invade healthy cells so they can’t spread the infection. And third, as the animation shows, your immune system is busy attacking the viruses whenever and wherever possible.

That is why most of the time, after a struggle (when you get a fever and need to lie down), your immune system rebounds, and, in time, so do you.

A health body with a strong immune system is able to fight off viruses, and other health issues more easily. Also when you body has run across a specific virus before it is ready to fight it. It has cataloged that virus and is on the look out for it and is prepared to produce specialized cells to attack it. The flu vaccinations you get are priming your body to be ready to attack if that virus is found. Those antibodies take about 2 weeks to build up in sufficient numbers to offer protection against the flu. Viruses are constantly mutating which helps them evade your detectors. This stuff is so amazing. And your body is just doing this stuff every day while you watch youtube or play basketball or…

How Lysozyme Protein in Our Tear-Drops Kill Bacteria

A disease-fighting protein in our teardrops has been tethered to a tiny transistor, enabling UC Irvine scientists to discover exactly how it destroys dangerous bacteria. The research could prove critical to long-term work aimed at diagnosing cancers and other illnesses in their very early stages.

Ever since Nobel laureate Alexander Fleming found that human tears contain antiseptic proteins called lysozymes about a century ago, scientists have tried to solve the mystery of how they could relentlessly wipe out far larger bacteria. It turns out that lysozymes have jaws that latch on and chomp through rows of cell walls like someone hungrily devouring an ear of corn.

“Those jaws chew apart the walls of the bacteria that are trying to get into your eyes and infect them,” said molecular biologist and chemistry professor Gregory Weiss, who co-led the project with associate professor of physics & astronomy Philip Collins.

The researchers decoded the protein’s behavior by building one of the world’s smallest transistors – 25 times smaller than similar circuitry in laptop computers or smartphones. Individual lysozymes were glued to the live wire, and their eating activities were monitored.

“Our circuits are molecule-sized microphones,” Collins said. “It’s just like a stethoscope listening to your heart, except we’re listening to a single molecule of protein.”

It took years for the UCI scientists to assemble the transistor and attach single-molecule teardrop proteins. The scientists hope the same novel technology can be used to detect cancerous molecules. It could take a decade to figure out but would be well worth it, said Weiss, who lost his father to lung cancer.

“If we can detect single molecules associated with cancer, then that means we’d be able to detect it very, very early,” Weiss said. “That would be very exciting, because we know that if we treat cancer early, it will be much more successful, patients will be cured much faster, and costs will be much less.”

The project was sponsored by the National Cancer Institute and the National Science Foundation. Co-authors of the Science paper are Yongki Choi, Issa Moody, Patrick Sims, Steven Hunt, Brad Corso and Israel Perez.

Encouraging Curiosity in Kids

How do you help make your children scientifically literate? I think the biggest thing you can do is encourage curiosity.

One way to encourage curiosity it is by answering their questions (and not saying: I am too busy, don’t bother me, don’t ask me?, stop asking why…). I know adults are busy and have all sorts of stuff we are trying to get done; and the question about why I need to wash my hands doesn’t seem worth answering. But I think anytime a kid is asking why is an opportunity to teach and encourage them to keep being curious.

It is very easy to shut off this curiosity, in our society anyway (we do it to the vast majority of people). The biggest difference I see between adults and kids is not maturity or responsibility but curiosity (or lack thereof in adults) and joy (versus adults who seem to be on valium all the time – maybe they are).

As they grow up kids will have lots of science and technology questions that you don’t know the answers to. If you want them to be curious and knowledgeable, put in the effort to find answers with them. You have to help them find the answers in a way that doesn’t turn them off. If you just say – go look it up yourself (which really they can do), maybe the 2% that are going to become scientists will. But most kids will just give up and turn off their curiosity a little bit more (until eventually it is almost gone and they are ready to fit into the adult world). Which is very sad.

Once you get them used to thinking and looking things up they will start to do this on their own. A lot of this just requires thinking (no need to look things up – once a certain base knowledge is achieved). But you need to set that pattern. And it would help if you were curious, thought and learned yourself.

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.

While walking in the park, see one of those things you are curious about and ask why does…? It is good to ask kids why and let them think about it and try and answer. Get them in the habit of asking why themselves. And in those cases when no-one knows, take some time and figure it out. Ask some questions (both for yourself – to guide your thinking – and to illustrate how to think about the question and figure things out). If you all can’t find an explanation yourselves, take some time to look it up. Then at dinner, tell everyone what you learned. This will be much more interesting to the kids than forcing them to elaborate on what they did today and help set the idea that curiosity is good and finding explanations is interesting.

It is fun as a kid if your parent is a scientist or engineer (my father was an engineering professor).

You often don’t notice traits about yourself. In the same what I know what red looks like to me, I figure we both see this red shirt you see the red that I do. But maybe you don’t. I tend to constantly be asking myself why. If I see something new (which is many, many times a day – unless I am trapped in some sad treadmill of sameness) I ask why is it that way and then try and answer. I think most of this goes on subconsciously or some barely conscious way. I actually had an example a few months ago when I was visiting home with my brother (who is pretty similar to me).

As we were driving, I had noticed some fairly tall poles that seemed to have really small solar panels on top. I then noticed they were space maybe 20 meters apart. Then saw that there seemed to be a asphalt path along the same line. I then decided, ok, they are probably solar panels to power a light for the path at night. Then my brother asked why are there those small solar panel on top of that pole?

Continue reading →

MIT Scientists Find New Drug That Could Cure Nearly Any Viral Infection

New drug could cure nearly any viral infection

The drug works by targeting a type of RNA produced only in cells that have been infected by viruses. “In theory, it should work against all viruses,” says Todd Rider, a senior staff scientist in Lincoln Laboratory‘s Chemical, Biological, and Nanoscale Technologies Group who invented the new technology.
…
There are a handful of drugs that combat specific viruses, such as the protease inhibitors used to control HIV infection, but these are relatively few in number and susceptible to viral resistance.

Rider drew inspiration for his therapeutic agents, dubbed DRACOs (Double-stranded RNA Activated Caspase Oligomerizers), from living cells’ own defense systems. When viruses infect a cell, they take over its cellular machinery for their own purpose — that is, creating more copies of the virus. During this process, the viruses create long strings of double-stranded RNA (dsRNA), which is not found in human or other animal cells.

As part of their natural defenses against viral infection, human cells have proteins that latch onto dsRNA, setting off a cascade of reactions that prevents the virus from replicating itself. However, many viruses can outsmart that system by blocking one of the steps further down the cascade.

Rider had the idea to combine a dsRNA-binding protein with another protein that induces cells to undergo apoptosis (programmed cell suicide) — launched, for example, when a cell determines it is en route to becoming cancerous. Therefore, when one end of the DRACO binds to dsRNA, it signals the other end of the DRACO to initiate cell suicide.

Combining those two elements is a “great idea” and a very novel approach, says Karla Kirkegaard, professor of microbiology and immunology at Stanford University. “Viruses are pretty good at developing resistance to things we try against them, but in this case, it’s hard to think of a simple path pathway to drug resistance,” she says.

Each DRACO also includes a “delivery tag,” taken from naturally occurring proteins, that allows it to cross cell membranes and enter any human or animal cell. However, if no dsRNA is present, DRACO leaves the cell unharmed.

Very cool stuff and potentially hugely beneficial. Just a reminder: this works against viruses – not bacteria (just as antibiotics do not work against viruses).

The Sun is a Miasma of Incandescent Plasma

They Might be Giants once again provide an enjoyable view into the wonders of science. Previously they published the video, The Sun is a Mass of Incandescent Gas. They published an updated video, a couple years ago, which captures the best current understanding based on the scientific inquiry process: Why Does the Sun Really Shine? (The Sun is a Miasma of Incandescent Plasma).

I really do love, They Might be Giants. Even before their focus on science I enjoyed their music. But they have done wonders with all their recent work. Go Giants. Get their DVD: Here Comes Science.

Their previous video, The Sun is a Mass of Incandescent Gas, Continue reading →

5% of the Universe is Normal Matter, What About the Other 95%?

Dark Matters from PHD Comics on Vimeo.

Great discussion and illustration of the state of our understanding of physics, matter, dark matter and the rest of the stuff our universe has from PhD comics. What is the universe made of? 5% of it is normal matter (the stardust we are made of), 20% dark matter and the other 75% – we have no idea!

Dark Cosmos is a nice book on some of these ideas. It is 5 years old so missing some of the latest discoveries.

Cancer Vaccines

A reader commented on a previous post (MIT Engineers Design New Type of Nanoparticle for Vacines) asking about how vaccines can fight cancer. Preventative vaccines can build up immune response to viruses which cause cancer. So the vaccine actually works against the virus which prevents the virus from causing cancer.

The U.S. Food and Drug Administration (FDA) has approved two vaccines, GardasilÂ® and CervarixÂ®, that protect against infection by the two types of human papillomavirus (HPV) – types 16 and 18 – that cause approximately 70% of all cases of cervical cancer worldwide. At least 17 other types of HPV are responsible for the remaining 30% of cervical cancer cases. HPV types 16 and/or 18 also cause some vaginal, vulvar, anal, penile, and oropharyngeal cancers.

Many scientists believe that microbes cause or contribute to between 15% and 25% of all cancers diagnosed worldwide each year, with the percentages being lower in developed than developing countries.

Vaccines can also help stimulate the immune system to fight cancers.

B cells make antibodies, which are large secreted proteins that bind to, inactivate, and help destroy foreign invaders or abnormal cells. Most preventive vaccines, including those aimed at hepatitis B virus (HBV) and human papillomavirus (HPV), stimulate the production of antibodies that bind to specific, targeted microbes and block their ability to cause infection. Cytotoxic T cells, which are also known as killer T cells, kill infected or abnormal cells by releasing toxic chemicals or by prompting the cells to self-destruct (a process known as apoptosis).

Other types of lymphocytes and leukocytes play supporting roles to ensure that B cells and killer T cells do their jobs effectively. These supporting cells include helper T cells and dendritic cells, which help activate killer T cells and enable them to recognize specific threats.

Cancer treatment vaccines are designed to work by activating B cells and killer T cells and directing them to recognize and act against specific types of cancer. They do this by introducing one or more molecules known as antigens into the body, usually by injection. An antigen is a substance that stimulates a specific immune response. An antigen can be a protein or another type of molecule found on the surface of or inside a cell.