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Readers who have some knowledge of electrical engineering could probably solve this exercise with ease (?!).

For those who do not have any idea about electrical engineering, here are the basic laws that would help (?!) in completing this exercise.

Kirchoff’s Current Law (KCL, also known as Kirchhoff’s first law, Kirchhoff’s point rule, Kirchhoff’s junction rule (or nodal rule), and Kirchhoff’s first rule), states…

At any point in an electrical circuit that does not represent a capacitor plate, the sum of currents flowing towards that point is equal to the sum of currents flowing away from that point.

Simplified, it reads thus…

At every node, the sum of all currents entering a node must equal zero.

and

Kirchoff’s Voltage Law (KVL, also known as Kirchhoff’s second law, Kirchhoff’s loop (or mesh) rule, and Kirchhoff’s second rule), which states…

The directed sum of the electrical potential differences around any closed circuit must be zero.

Here is the exercise….

Please apply Kirchoff’s Current and Voltage laws to the following figures….

Figure 1

Figure 2

[click the links to open the figures in new windows]

If you come up with the correct solution, I promise to make you the Power Minister when I become Prime Minister of India.

[Many thanks to my friend Shankar who sent this to me via email].

This is not a post about the utility (or not) of doing a CT scan to diagnose acute appendicitis.

I came across this at Shadowfax’s blog. It’s a great story, which just happens to be about appendicitis & CT scan.

I recently cared for a young boy with abdominal pain. He was about six years old, and had pain in his lower abdomen for about 12 hours prior to coming to the ER. His parents, Ukranian immigrants, were really nice people. Their English could have been a little better, but we could understand one another perfectly with a little effort and we got along fine. They were among the nicest people I have had the pleasure of interacting with in the ER in a long time. They were reserved, polite, and deeply respectful towards me in a manner that struck me as almost old-fashioned, and they were very concerned about their son, their only child, who was in a lot of pain and had never been ill like this before.

I was almost certain that he had appendicitis, and after explaining this to the parents, I called the surgeon to see if we could just take him to the OR for a laparotomy. You may recall I’ve run into trouble with this sort of thing before, and the surgeon, the same surgeon as before, wouldn’t bite this time. In fairness, the story wasn’t quite perfect — the pain didn’t localize quite right, the white count wasn’t really high enough, etc — so she asked me to image the child to verify the diagnosis, which is reasonable.

Read the rest of the story at Movin’ Meat: Triggers.

Blog friend GruntDoc hosts the 200^th edition of Grand Rounds, the medical blog carnival:

I’m Honored to be the first Sixth Time Host, but more importantly to be the host of the 200th Edition of MedBlogs Grand Rounds.  Dr. Nick Genes deserves all the credit for starting (and maintaining) this wandering collection of links to the best of the MedBlogosphere (thanks, Nick!).

There were more than 40 submissions this week, and here they are in the order they were received, (with my ER Doc attention span review in parenthesis at the end of the link):

GruntDoc » MedBlogs Grand Rounds 4:44 The 200th Edition!.

H/T: The Happy Hospitalist

[H/T]

bookofjoe: British Army Challenger 2 Tank v Range Rover Sport: ‘Top Gear’ Throwdown.

As Joe, the ‘world’s most popular blogging anesthesiologist‘ says, “That’s one impressive off-road car”.

Mandela Celebrates His 90th Birthday - NYTimes.com

Many thanks to David for finding the fix for the problem and posting a detailed ‘how-to’ it in his blog. I followed the instructions and got my missing categories back.

David Cumps » Wordpress 2.6 Upgrade - Fix Missing Categories.

He has indeed given something back to the WP community.

Thanks also to my blog friend Lekhni for tipping me off about David’s post.

PS: I changed the permalink structure for my posts. Made them ‘pretty‘ from the default ‘ugly‘. If any of you have linked to my older posts, the links probably will not work now.

After hesitating for months out of fear that I would screw up somehow and lose my entire blog, I finally took the plunge and upgraded to the latest version of WordPress.

It was a giant leap from version 2.0.2 to 2.6 and thankfully the upgrade process was smooth. It took a very long time for me to backup my database. My blog files were only 60 MB, but my WP database was 156 MB. Don’t ask me how. I have no idea how it got so big. I did purge all spam from Akismet. I suspect that the Firestats Plugin was hoarding a lot of data. Anyway, that is something that I will have to worry about when I next backup my database.

I must say I love the Dashboard in the new WP. Lots of new options to explore. Quite a few of the Plugins that I used are not compatible with the new version. Not surprising, as the version was released only this week.

I found a major glitch just now. All my categories have disappeared. Eaten by the WP Gremlins, perhaps?!

There is a list of categories which shows blank spaces or empty quotes - “” - in place of the category names. The list shows the number of posts in each of those blank categories though. That reassures me. Whatever is wrong ought to be correctable. I have explore the support forums to see if there are any solutions. Any ideas for recovering the category names are welcome. Please leave a comment if you know how to get them back.