Education is expensive

A used textbook should not cost nearly $200!

The most expensive textbook in the college bookstore my freshman year of college was the Calculus textbook. The brand new, thick tome cost a shocking $118! I used it for two semesters, and then I lent it to a roommate for a semester. So the distributed cost was not so terrible.

But I just cannot get over the sticker shock for this relatively petite stats textbook.

Oy vey! I just found Huffington Post this article on the rate of increasing textbook prices.

Best job title EVER

"Purpose: Find problems. Fix them. Make a better factory. Make a difference."

A vision for better science policy...

6.02 x 10^23

Just another...

HPLC chromatograph 

OR

 a day in the lab

Glow-in-the-dark transgenic cats

I haven't had a chance to read this article yet, but these FIV-resistant (Feline Immunodeficiency Virus, the feline equivalent of HIV) kittens are so cute. Expression of the green fluorescent protein (GFP) in this five month old transgenic cat indicates that it has acquired the protective gene.

Unless it's a bananaphone...

Handy chart that explains radiation levels in comparison to the doses we receive daily/annually, from one of my favorite web-comics:Click on the image to see the full-sized (readable) version.

Chemical Analysis

MATERIALS SAFETY DATA SHEET for WOMAN

ELEMENT: Woman

SYMBOL: Wo

DISCOVERER: Adam

ATOMIC MASS: Accepted at 51.6 kg, but known to vary from 40-200 kg

OCCURRENCES: Copious quantities in all urban areas.

PHYSICAL PROPERTIES:

1. Surface usually covered in painted film.
2. Boils at nothing; freezes without know reason.
3. Melts if given special treatment.
4. Bitter if incorrectly used.
5. Found in various states from virgin metal to common ore.
6. Yields if pressure applied in correct places.

CHEMICAL PROPERTIES:

1. Has great affinity for gold, silver, and a range of precious stones.
2. Absorbs great quantities of expensive substances.
3. May explode spontaneously without prior warning and for no known reason.
4. Insoluble in liquids, but activity increases greatly by saturation in alcohol.
5. Most powerful money reducing agent known to man.

COMMON USES:

1. Highly ornamental, especially in sports cars.
2. Can be a great aid to relaxation.
3. Very effective cleaning agent.

TESTS:

1. Pure specimen turns rosy pink when discovered in the natural state.
2. Turns green when placed beside a better specimen.

HAZARDS:

1. Highly dangerous except in experienced hands.
2. Illegal to possess more than one, although several can be maintained at different locations as long as specimens do not come into direct contact with each other.

Happy Mole Day!

For those of you confused by the concept of a mole, the mole represents a number. Just as the term dozen refers to the number twelve, the mole represents the number 6.02 x 10²³.


I baked "Mole'asses Cookies" to take to work. I found the cutest recipe to use as an experiment/activity for students using chemical nomenclature and measurements.


In my mole day searching I also stumbled upon a cute post about mole day disambiguation at Porch Pondering by Rae.

(A few links in case you want to learn more about Mole Day and/or Avogadro's number....)

I wish you all a Happy Mole Day!

Weird Science

This YouTube video is something that I'll have to remember for a future science demo. (I think I may show it to my little cousins this weekend.) It shows that cellophane tape makes 1-side frosted glass appear to be transparent. Quite striking!

The reason this works is pretty straightforward from the physics perspective. Frosted glass looks whitish because its surface has been covered (by sandblasting or something analogous) with little irregularities that have a typical size scale comparable to the wavelengths of visible light. Because of the difference in index of refraction between glass and air, these little irregularities diffusely scatter light; and they do a pretty equitable job across the visible spectrum. (This is why clouds are white, too.) By coating the glass intimately with a polymer layer (with an index of refraction closer to the glass than that of the air), one is effectively smoothing out the irregularities to a large degree.
This is essentially the same physics behind why wet fabrics often appear darker than dry fabrics. Some of the apparent lightness of the dry material is due to diffuse scattering by approximately wavelength-sized stray threads and fibers. A wetting liquid acts as an index-matching medium, effectively smoothing out those inhomogeneities and reducing that diffuse scattering.

Pretty cool, huh?!?

Dipolar

I have a few favorite chemistry t-shirts. One has a Texas Ranger badge with the five sub-disciplines listed one each arm of the star. Another has a classic joke: “Protons have mass? I didn’t know they were Catholic.” The one that seems to describe the way I have felt this past week is also the one least clear to non-chemists, eliciting the most odd looks and questions when worn. It simply says “I’m having a δipole moment.”

A brief chemistry lesson is necessary to explain this statement.

You know that molecules are surrounded by a cloud of electrons, just as a single atoms are. These electrons don't just stay in the same place and evenly separated all the time; they move around... a lot. Therefore, at any one time there could be more electrons over one side of the cloud than the other. This would give that side of the cloud a slightly negative charge and the other side a slightly positive charge (but only for a very short time). This change in charges is due to the dispersion of electrons. The slightly negatively charged side of the cloud will cause the electrons in a neighboring molecule's cloud to move away from it because like charges repel. This gives the neighboring molecule a slight positive charge on the side that is next to the original molecule's slightly negative charge; thus inducing a dipole. A permanent magnet (like the one’s one your fridge) owes its magnetism (“north” and “south” poles) to the intrinsic magnetic dipole moment of the electron.
A neutrally charged molecule, with no dipole develops a dipole moment when a charge particle or molecule with a dipole comes close enough. And dipole moments are represented by the Greek symbol delta δ (i.e. δ+ and δ-) (the fraction of a unit charge on each atom in a molecule).
Any questions class?

This week felt like a molecule of water, wich has a positive induced dipole on the Oxygen flanked by Hydrogens each bearing a partial positive charge. The week started off well, fairly typical happenings. Then Wednesday struck and I felt oppressed by the world. Nothing seemed to go right for the rest of the work week—the boss was in a tizzy over something for which I cannot provide a perfect solution; apathetic students; late for a workshop. Friday evening things started looking brighter again. Some of my favorite Sisters were visiting for the weekend--visiting parishes to promote vocations, speaking on the Feminine genius at the university, and witnessing a Jesuit priest’s final vows. The days were brighter and warmer, and I could see the positive more easily.

Hydrogen: Talking the long-way home by walking around the lake in the park and still getting home before sunset
Oxygen: Trying to communicate effectively (and calmly) with some collaborators on a long-overdue project with which I never wanted to become involved; Feeling pulled in several directions and unable to concentrate
Hydrogen: Witnessing my favorite SJ’s profession of final vows while he knelt in front of the Most Holy Sacrament of the Altar (Beautiful!)

Sweet dreams.

Blonde Goes Green?

Today at the American Chemical Society meeting, scientists from Japan reported development of what could be the world's first "green" hair bleach, an environmentally friendly preparation for lightening the color of hair on the head and other parts of the body without the unwanted effects of the bleaches used by millions of people each year. Kenzo Koike, Ph.D., pointed out that traditional hair bleaches rely on hydrogen peroxide. He described isolation of an enzyme from a type of "white-rot" fungus that has also shown potential to degrade and clean up pollutants in soil and which naturally degrades melanin. Koike proposes that it could be added to traditional hair bleaches to prevent hair damage, leading to hair care products that use less hydrogen peroxide (a "greeener" product overall). Laboratory tests show that the enzyme is effective in bleaching synthetic melanin and melanin in human hair.

Image: The color changes from conventional bleach are apparent as is the corresponding damage caused to hair fibers (bottom image). (Credit: Kenzo Koike)

Glow in the Dark

One of Cate’s top ten good things about living in Indiana is the fireflies. While I am not a biologist and know very little about the critter itself, I am well versed in the reaction that occurs to produce the glowing abodomen and it's biomedical applications. In response to my comment, Cate has invited me to teach her chemistry (and by extension anyone else who stops by here). I am never one to turn down an opportunity to teach, so here goes.

Bioluminescence (from the Greek bios meaning living and Latin lumen meaning light) is the production and emission of light by a living organism as the result of a chemical reaction in which chemical energy is converted to light energy. For a firefly the reaction is the oxidation of luciferin. The basic component sof the reaction are as follows:

Oxygen (O2) + Luciferin --> Oxyluciferin + Energy (Light)

This reaction occurs very slowly independently, but in the presence of luciferase (an enzyme) the reaction rate increases.

Luciferase can be used as a reporter system for biomedical imaging research. Cells can have DNA added to them that includes the luciferase gene linked to a gene of interest. When the gene of interest is expressed by the cells, so is the luciferase. When the substrate, luciferin, is added, if luciferase is being expressed, the luciferin will be oxidized and the cells will glow. If luciferase, and hence the gene of interest, are not being expressed, then any bioluminescence will be minimal to non-existent. Thus, the luciferase reports on the activation status of one’s gene of interest.
This image overlays a bioluminescent image over a photo of a mouse who has been implanted with breast cancer cells labeled with a luciferese reporter gene. Serial bioluminescent imaging of a tumor such as this one will allow the researchers to monitor tumor growth, or possibly metastasis, non-invasively. While such a method would not be possible for human patients, it is helpful in the drug design and testing.

Any questions?

Exception to the Definition

Every chemistry student knows that a compound consists of two or more different elements bonded together in a fixed mass ratio, with different physical and chemical properties from the constituent elements. But as always, someone has found an exception to the rule.
An international group of scientists have discovered a new chemical compound that consists of a single element, boron. They report that at a high pressure and temperature pure boron can assume two distinct forms that bond together to create a novel 'compound' called boron boride. (Nature, doi:10.1038/nature07736)

"High pressure causes otherwise identical boron atoms to become chemically distinct by spontaneously polarizing and either losing or gaining electrons. The resulting ions can form different structures which bind together as a single element compound."

I'll spare you from the gory details here. But please read it yourself if you're curious.

Whenever I teach the definition of a chemical compound from now on, I'll know that it's just another lie we tell our students.