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Finally, it lacks a section of advanced technology.

http://www.phy.davidson.edu/in...

I HIGHLY recommend these.

It's not just humans. You may find this interesting to read, as well as this. Male fish are definitely not supposed to have female characteristics.

Oh really?

forgot a couple:
http://www.phy.davidson.edu/instrumentation/NEETS.htm
http://aggregate.org/hankd/piaee12.pdf

I found a nice little illustration of the effect temperature has on the equilibrium of this reaction here. The calculation is actually for the related reaction using carbon (as coke) instead of methane, but the equilibrium constants are about equal for the temperatures discussed here. At atmospheric conditions on Earth, the equilibrium can be considered as shifted completely to the left. Virtually no carbon monoxide is produced from this reaction at temperatures less than about 600K. At a temperature of 956.7K, the levels of carbon and carbon monoxide are equal, and at higher temperatures, carbon monoxide is On GJ 436b, with a temperature of 800K, the equilibrium should still strongly disfavor CO production, and the calculation suggests that there should be around 13.6 times as much carbon (or methane in the case of GJ 436b) as there is carbon monoxide.

However, the researchers determined that "GJ 436b's atmosphere is abundant in CO and deficient in methane (CH4) by a factor of ~7,000." The only way the planet could have gotten an atmosphere like that through this reaction equilibrium alone is if its temperature is really around 2000K instead of 800K. The researchers therefore argue that it's far more likely that some other mechanism is disrupting this equilibrium, like polymerization of methane that pulls it out of the system. In their Nature paper, they include a a chart of the atmospheric ratios of gas giants, both in our solar system and exoplanets; nothing else known has a CH4/CO ratio like that seen for GJ 436b.

Here are two sources to give you a start.
The Art of Electronics
Neets

Are you, by any chance, secretly a lion?

Can they get blue as well as green and red?

yes yes yes

Can they be injected into skin cells?

Yes, but you may not want to... and it may not last long

Can the glow be controlled by the nervous system?

I'll say 'not yet' rather than a flat out 'no'.

Which tattoo parlour can give me my glow in the dark thought controlled, full color tattoo?

The tools arent that hard to make but getting your hands on the (G)/(R)/(B)/FP is slightly harder... I have them in my lab ;-)

Just give me...
1) these (check),
2) a template mask -one for each colour (easy enough)
3) And the GFP in the appropriate DNA vector,
4) ???
5) profit
6) and i can paint with 1" dots a tattoo...

I am ***SO*** doing this on the next plant I shoot (not my pic), I only use G(reen)FP on tobacco mainly, so they will have to be monochrome. oh well. just have to put up with green glowing smiley faces on some leaf! No i wont be doing myself (a. I dont have a human vector and b. im not *that* stupid)

p.s. Yes, doing a PhD does make you look for entertainment in odd places.

I looked high and low for GFP tattooed mice (just green dots), which i know i've seen, but google is not my friend.

The entire US Navy Electricity & Electronics Training Series (NEETS) is online in PDF book format here:

http://www.phy.davidson.edu/instrumentation/NEETS.htm

This explains virtually every part of electronics you could possibly want.

(Bonus: as it was produced by the US government, there is no copyright; download, read, print, copy, etc. as much as you'd like.)

As a former Electronics Technician in the Navy, I have to agree with the parent. The Navy Electricity & Electronics Training Series (NEETS) is a great series of books that teach the basic of electronics. After studying these manuals, I successfully built a Superheterodyne receiver, also known as your basic radio receiver. You can find all of the NEETS modules online here in PDF format. I still have them on CD from when I went through the training in 1998.

As for your link to electricity misconceptions, all I can say is that I find the information there disagrees with what I was taught by the US Navy. It reminds me of the old electron flow vs hole flow arguments. The important part is that electric circuits work the same regardless of what you're philosophy is concerning the movement of electrons.

Best of luck with your search. Just remember that soldering irons are HOT. I've heard good things about the Art of Electronics as well.

Aero

http://webphysics.davidson.edu/Applets/Applets.htm l

This page (in German, scroll down for English version) has more about it, including citations from the original works by Chladni, more pictures of the famous figures on metal plates, and a link to http://www.wfu.edu/physics/demolabs/demos/avimov/w aves/chladni_plates/resonance_square.MPG/ (21MB) from Wake Forest University. This is the longer version of the experiments that can be seen in the video linked in the summary. There's also a link to http://www.phy.davidson.edu/StuHome/jimn/Java/mode s.html/ which has an interactive java applet to plot Chladni figures.

That's true. I wonder if, like some other fish, it can change its sex whenever it wants to, as well. ALMOST makes me want to be a fish.

The discovery of a 'universal' nucleant (close to the one suggested by the authors of this study) and the development of a matrix to encourage crystallization would greatly speed the screening process, and ultimately, crystallization of proteins.

Ok, so I don't know a ton about nuclear medicine, I know just enough to be dangerous. Protein crystallization allows us to see it's structure whereby we better understand its function.

The reason this bit of news is so big is that it will (hopefully) allow researchers a way to quickly look at the structures of proteins in such as (in the second link) infectious diseases transmitted by prions, or protein particles. Prions seem to be pure protein; they contain neither DNA nor RNA.

If we can understand the shape and formation of proteins, we can understand how viruses and cells work because proteins are the building blocks. Viruses are obviously first on the chopping block as they are the smallest and infect millions of people world wide (AIDS, influenza, the common cold, etc.).

You posted information from a known corporate shill as your rebuttal. I was hoping you didn't know that, but it seems like you do and just don't care.

Actually your definition of corporate shill does not agree with mine. Unlike you, I don't automatically consider anyone who argues that the government made an error to be a shill, I don't consider a professor engaging in intellectual debate to be equivalent to a testing lab fudging a test for a client. Anyway, please continue with your failed attacks on the messenger and mislabel anyone who disagrees with your pet government ruling.

From the link you posted: Richard McKenzie is a professor in the Graduate School of Management at the University of California, Irvine; author of Trust on Trial: How the Microsoft Case Is Reframing the Rules of Competition (Boston: Perseus, 2000); and an adjunct scholar of the Cato Institute...

The professors stated the book grew out of a graduate economics class. "McKenzie first became interested in Microsoft's legal troubles three years ago while planning a course on "network economics" for MBA students at The University of California, Irvine, where he is a professor of economics in the Graduate School of Management."
http://www2.davidson.edu/news/news_archives/archiv es00/00.09mckenziereport.html
As for being an "adjunct scholar", you realize that probably means they publised a paper or something? That does not mean he is on staff. Anyway, please continue with your failed attacks on the messenger and cite away on articles that the professor did not write like the cigarette one.

... and also from the PDF: Published by the Cato Institute So obviously this has nothing to do with the Cato Institute (sarcasm).

Uh, "published by" refers to the "Policy Analysis" journal, the PDF, not the book.

I'll admit that I was incorrect here but not about the spirt of the discussion. Arguing the exactness of the 70,000 number is not the same as rebutting the judge's point.

Actually he seemed to be arguing that the number and it's important/unimportance demonstrated the judge's fuzzy logic, and that findings based on such fuzzy logic cannot support a conclusion of law, that the judge seems to have erred. The judge's Apple example and failure to consider that something other than only have 12,000 apps may be limiting Apple's marketshare was a good rebuttal.

"That is simply rebut by the fact that the majority of home users do very simple things. They could do those things with a Mac, they could do those things with Linux, but they choose not too."

This is not a simple rebut as it's a complex issue. In a similar vein I can say that consumers "choose" not to write all their own operating systems and applications."

Please do so, please equate using Mac/AppleWorks/etc and Linux/OpenOffice/etc with writing your own OS and apps.

"Consumers can, and will, replace MS whenever they feel like it."

In the same way that we can go to Mars any time we want. In absolutist terms, both statements are true, but functionally they aren't. There is a HUGE cost assosciated.

Yet millions use Mac and Linux for their personal needs. I suppose you believe that is faked on some Hollywood backlot lot like the Apollo landings? :-)

Sorry to reply to my own post, but what follows is a link to the full text of the article referred to in the parent. PDF WARNING.

Hybrid speciation in experimental populations of yeast.

And also, the requisite CoralCache mirror:

http://www.bio.davidson.edu.nyud.net:8090/Courses/ Bio343/papers/Greig.pdf

We're trying to figure out if it's even possible without unbelievable costs here at Davidson College, and the (some of) faculty is resisting like there's no tomorrow. We're trying to get the word out to students, but there's no voice for civil liberties yet. We already do next to nothing when we get C&Ds.
I know for a fact we're not CALEA-compliant today. And I'm trying to spread the word to create resistance.
(Oh, and The Davidsonian's front page headlines this week: "Student pulls knife at Warner," "Students robbed in satellite parking lot," and "Town makes plans for transit rail to Charlotte.")

And second opinions here and here

That's true when the helicopter is sitting still, but not when it is moving.

Think of a wheel rolling on the ground. The center of the rotation is actually the point where the wheel touches the ground, NOT the center of the wheel. This is only true when the wheel does not slip of course.

Here's a link with some information about rolling.

Brett

1. air resistance
2. rolling resistance

1. air resistance
2. GRAVITY (w=mg)

It isn't really sad, I suppose. :-) I meant it in a self-deprecating-humorous way.

As for why the family of proteins and genes is named "hedgehog," it has nothing to do with the shape of the protein. Rather, according to this page, "The original hedgehog gene was found in Drosophila and was named for the appearance of the mutant phenotype which causes an embryo to be covered with pointy denticles resembling a hedgehog."

Naked Mole Rat?

Spurred on by your additional info, I poked around to find out more about shh. I took a look at a Sonic Hedgehog page at Davidson College. I was surprised to find out that shh gets its name from the video game character. "The first two homologues of hedgehog were named after species of hedgehog and the third was named after the video game character (Gilbert, 2000)."

A press release over at the University of Chicago Hospitals site elaborated: "Researchers found three different versions of the "hedgehog" gene but only two kinds of real hedgehogs, so they named the third gene after the cartoon character."

I know you said they named them after things in the hedgehog family, so I assumed there must be an actual "sonic hedgehog" to go along with the Indian and desert hedgehog. No less likely that the animal would have a crazy name than the protein, I figured. My ignorance shows once again...

And Halo-, looks like you had a point about biologists, physicists, and computer geeks assigning crazy names to things.

Sorry, link for parent post is here

Don't forget the inspiration of the name of the morphogenetic protein.

...without the means to forge swords, much less spaceships

, much less hemoglobin.

<a href="http://webphysics.davidson.edu/Applets/Poiss on/Faraday.html">Faraday Cages</a>

<URL:http://webphysics.davidson.edu/Applets/Poisso n/Faraday.html>

<a href="http://webphysics.davidson.edu/Applets/Poiss on/Faraday.html">Faraday Cages</a>

<URL:http://webphysics.davidson.edu/Applets/Poisso n/Faraday.html>

The really interesting information is a reverse-engineered interpreter. Who cracks the ribosome code will harness the lathe of heaven.

I think you're talking about a DNA Microarray.

It allows you to get the expression profile of the cell. More info here.

Flash tutorial here.

Interestingly enough, it's the reverse transcriptases that are used by viruses like HIV to embed themselves in our genome that allowed cDNA technology and therefore Microarray technology to become a reality. We could have made the complimentary DNA strands that the messenger RNA binds to using other methods, but it would have been much harder.

Airbus was conducting trials many years ago with a covering that was striated like shark skin. They measured small drag reductions, but I haven't read anything about the concept in recent years. I suspect Airbus found that it was hard to keep the surface maintained properly.

http://www.spc.org.nc/coastfish/News/Fish_News/84/ Shark-skin-planes.htm
http://www.bio.davidson.edu/Courses/anphys/2000/Tu scano/Applications.htm

What is a Faraday Cage?

A Faraday Cage is the phenomenon that occurs when you surround an object with a conductor (read: metal), basically stopping all charge from entering/exiting conductor.

Here is a simple decution of why:
Gauss's Law states when a conductor is charged the charge resides on the surface of the object--with a solid metal sphere, all the charge would be sitting on the outside surface.
Now imagine a hallow sphere: The charge can only be on the surface of an object, therefore this allows no charge 'inside' the sphere.

Examples in everyday life:
->Lightning strikes your car
-> Lightning strikes a plane. (Studies say by average, every plane in the US is hit by lightning once a year)
-> Your Cell phone gets poor reception in basements and lower floors of buildings because of the rebar in the concrete.

I found a cool app. of Faraday's Cage where you control the charge--really helpful if you still don't get it.

Most Europeans (except the British) have first hand experience of war and real lack of freedom.

That's not true. Most europeans have no concept of war. Most of those that have experienced the privations of war are dead (except in those countries that can't resist a good civil war).

Countries like the US and Britain think it is a good idea to invade a defenceless country and even worse, try to make out that those that do not want to kill defenceless people are cowards

Oh please, get off your high horse. France didn't get involved because it was still owed a lot of money from arms sales in the 1980's and illegal sales in the 1990's.(the war referred to in the following quote is the Iran/Iraq war)

In 1987 the Paris-based Le Monde estimated that, between 1981 and 1985, the value of French arms transfers to Iraq was US$5.1 billion, which represented 40 percent of total French arms exports. Paris, however, was forced to reschedule payment on most of its loans to Iraq because of Iraq's hard-pressed wartime economy and did so willingly because of its longer range strategic interests...French military sales to Iraq were important for at least two reasons. First, they represented high-performance items. Iraq received attack helicopters, missiles, military vehicles, and artillery pieces from France. Iraq also bought more than 400 Exocet AM39 air-to-surface missiles and at least 200 AS30 laserguided missiles between 1983 and 1986. Second, unlike most other suppliers, France adopted an independent and unambiguous arms sales policy towards Iraq. France did not tie French arms commitments to Baghdad's politico-military actions...(source)

More recently, France helped move missile material from China: "The French connection - brokering the deal among the Chinese producer, the Syrian land transporter and the Iraqi buyer - is no great secret to the world's arms merchants. French intelligence has long been aware of it. The need for a French export license as well as UN sanctions approval may have been averted by disguising it as a direct offshore sale from China to Syria." (source)

France didn't get involved because it was owed money and knew once the deals were exposed wouldn't receive a franc.

That is why countries like France and Germany do not want to go to war for oil.

Really? So by implication the US and GB went to war for oil. Can you support this? I'm not aware of any "oil dividend" either nation has received...no spoils of war. You shouldn't spout rhetoric unless you can support it.

The real reason france and germany didn't go to war is because going to war would interfere with vacation time.

Germany has the shortest work week of any industrialized nation in the world. Depending upon the source, the average German work week ranges between 35 and 38.5 hours. In addition, Germany has a number of national holidays, which decrease the calendar work year that already includes between four and six weeks vacation. (source)

Of course, the french have that 35 hour work week with a similar amount of vacation time. See, that's why all the useful things like the Internet and computer you are using and the airplane you take on vacation were invented in the US.

I work with femto-second lasers. I have used them in living cells for a variety of applications. Two of which involve destroying structures inside of living cells. Of course, these structures are placed into the cells by us (injection, knock-in, electroporation, etc). It's not an extremely new technique, it's just being used in a slightly new way. Some of the similar techniques are known as uncaging, FRAP, and more.

Personally, I rarely find anything that groundbreakingly new in Nature. Well, that's not exactly true. There is plenty of new data, and new applications and/or refinements of old techniques. There generally aren't wholly original techniques or completely new instruments discussed in that journal. My personal preference for that sort of thing are some physics journals.

One other thing, that may be of interest to /., semiconductor nanocrystals are starting to pop up in similar research. They are quite useful, if still hard to work with (they don't behave like most biological molecules). I got interested in quantum dots about a year ago, and have done a bit of work with them, but would like to do some more (when I find the time).

See this page about octopus circulatory systems. The oxygen carrying chemical is called hemocyanin, not cyanoglobin, and does contain copper.

Blue copper-based horseshoe crab blood also contains hemocyanin.

Artificial neural nets are one way to do this, but statistical methods are more or less analogous and have the advantage of being highly optimizable. Personally I don't understand the details, but Very Smart Mathematicians have found ways to optimize models like Singular Value Decompositions (SVDs) so that they can be calculated orders of magnitude faster than models that cannot be represent as formally using mathematics.

The bottom line is that statistical methods are probably the way that we will end up producing brain-like behavior on computers, and the fact that there are promising results already is heartening. Yes, for truly intelligent behavior a lot of domain knowledge will also be needed, as you point out. But I don't see any reason why the extraction and mapping of this knowledge couldn't also be achieved with large training corpora and statistical methods, rather than hand-crafting.

You forgot the Faraday Cage

Well, that depends on how long you want to hold the gases. At any given temperature, the molecules of a gas at thermal equilibrium (or practically speaking, anywhere close to it) will have some distribution of speeds. Some molecules will travel faster, some slower. The mathematical expression characterizing this range of speeds is the Maxwell distribution. Here's a mathematical treatment of the Maxwell distribution; this page presents a nifty Java applet showing how this equilibrium takes place.

Note that a plot of population vs. speed, the Maxwell distribution tails off at higher velocities, but never actually goes to zero. In an atmosphere, this means that a small number of molecules will periodically get kicked up to above escape velocity through collisions with other molecules in the gas. If they happen to be heading the right direction, then they will escape into space.

Each molecule in a gas (on average) has roughly the same amount of kinetic energy. Earth's atmosphere contains very little hydrogen and helium because these light elements travel faster for a given amount of kinetic energy and escape more readily. A good part of the velocity distribution for these species is above escape velocity. Oxygen and nitrogen (not to mention water vapour and carbon dioxide) are significantly heavier, and bleed off at a much lower rate.

Moving to Mars. The surface gravity is only about forty percent that on Earth, if I remember correctly. It's a much shallower gravity well, and escape velocity is much lower (5 km/s on Mars vs. 11 km/s for Earth). Since kinetic energy is a function of the square of velocity, it takes a significantly smaller push to move a molecule out of Mars' hold. Nevertheless, there actually is still only a very small tail of the Maxwell distribution that sits above Mars' escape velocity.

I should also mention that there are sputtering processes that remove gas from the Martian atmosphere. Lacking a strong magnetic field to deflect the solar wind, a significant amount of gas is lost to sputtering, as well.

Nevertheless, even the most pessimistic estimates suggest that an atmosphere similar to Earth's would last tens of thousands on years on Mars. A short lifespan in terms of planetary evolution--a long time for human beings. Even the Moon would take from one to ten thousand years (depending upon who you ask) to bleed off an Earth-like atmosphere. Recall that Mars has surface features strongly suggestive of flowing surface water. (Liquid water requires an appreciable atmosphere, otherwise it just boils off.) That sort of erosion takes a long time to happen, which further supports the notion that Mars can hold on to an atmosphere, at least for a few million years at a time.

Without having a PhD, Jimmy Eng ( Eng bio 1, Eng bio 2) has done a helluva lot for the field of proteomics devoloping the groundbreaking software SEQUEST and related utilities.

Even if it is/were possible (has anyone actually gone to the trouble to email the scientist who supposedly did the experiments?), there would be some severe expected problems.

They're talking about interfering waves. That means pulsating DC, if not straight AC. Get this up to a frequency to even be useful (ala GHz to compete with CPU or networking technology), and suddenly you're broadcasting your signal. (Though coax's construction does cause some muting of this, IIRC) And putting it on silicon is a thing for Intel to do.

And just for proof that it's not possible: "superposition."

It says that waves will pass through each other and come out the same on the other side. Easiest to see in a ripple tank, or maybe in a physlet.

Even if it is/were possible (has anyone actually gone to the trouble to email the scientist who supposedly did the experiments?), there would be some severe expected problems.

They're talking about interfering waves. That means pulsating DC, if not straight AC. Get this up to a frequency to even be useful (ala GHz to compete with CPU or networking technology), and suddenly you're broadcasting your signal. (Though coax's construction does cause some muting of this, IIRC) And putting it on silicon is a thing for Intel to do.

And just for proof that it's not possible: "superposition."

It says that waves will pass through each other and come out the same on the other side. Easiest to see in a ripple tank, or maybe in a physlet.

In case you want to write software to help with the "online lab" part of courses or perhaps simply illustrate certain ideas in a graphical fashion, take a look at Physlets. These are open-source Java libraries for writing physics-related Java programs/applets. Award winning, no less.

-Rahul

Surrounding something with a conductor (ie copper wiring cage) to mask out EM transmissions is called a Faraday Cage.

(quick definition here
Nifty stuff here too.
Anything more, just use Google.


POpe