2024-04-19 09:00
In Chapter 10 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss negative feedback loops. Feedback is often used to maintain an important variable nearly constant. T… Read More
Blog Directory > Arts & Entertainment Blogs > Intermediate Physics for Medicine and Biology arts-and-entertainment Blog >
Intermediate Physics For Medicine And Biology Blog
hobbieroth.blogspot.com
A blog about physics applied to medicine and biology
2024-04-12 09:00
Are Electromagnetic Fields Making Me Ill?,by Brad RothEvery year the Kresge Library at Oakland University hosts an event called “Authors at Oakland” where they honor publications… Read More
2024-04-05 09:00
Recently I was reading an article by Ramsay Lewis and Yuhong Dong in The Epoch Times titled Invisible Electromagnetic Fields: Do They Harm Your Health? My friend and colleague David Garfinkl… Read More
2024-03-29 09:00
William Catterall, known as “the father of ion channels,” died on February 28 at the age of 77. Russ Hobbie and I cite Catterall’s article on the structure of sodium ion ch… Read More
2024-03-22 09:00
German biophysicist Erwin Neher turned 80 last week. Neher and Bert Sakmann received the 1991 Nobel Prize in Physiology or Medicine for their development of patch clamping: a method to recor… Read More
2024-03-15 10:31
Gene Surdotovich and I are hard at work preparing the 6th edition of Intermediate Physics for Medicine and Biology. One change compared to the 5th edition is that we are redrawing most of th… Read More
2024-03-08 10:00
I've always been fascinated by Stirling’s approximation,ln(n!) = n ln(n) − n,where n! is the factorial. Russ Hobbie and I mention Stirling’s approximation in Appendix… Read More
2024-03-01 10:39
Intermediate Physics for Medicine and Biology provides, for the first time, a textbook about the role that physics plays in medicine.
Well… no.
I recently found a textbook that prec… Read More
2024-02-23 10:00
Allan was born in Johannesburg, the youngest of three children. He spent his teenage years in Cape Town, and was interested in debating, tennis, and acting. He also loved astronomy, which tr… Read More
2024-02-16 10:00
Numerical Methods That Work,by Forman Acton.The American computer scientist Forman Acton died ten years ago this Sunday. In Intermediate Physics for Medicine and Biology, Russ Hobbie and I c… Read More
2024-02-09 10:00
Robert Adair.Photo credit: Michael Marsland/Yale University.I try to write obituaries of scientists who appear in Intermediate Physics for Medicine and Biology, but for some reason I didn&rs&hell…Read More
2024-02-02 10:00
“Havana Syndrome”: A Post Mortem,by Bartholomew and Baloh.Remember the Havana Syndrome? You don’t hear much about it anymore. Recently I read an article titled “&lsqu&hell…Read More
2024-01-26 10:00
I just learned that my friend Craig Henriquez passed away last summer. Craig earned his PhD at Duke University in their Department of Biomedical Engineering under the guidance of the renowne… Read More
2024-01-19 10:00
Last week, the plug door panel on an Alaska Airlines Boeing 737 Max airplane detached during flight, leaving a gaping hole in the side of the fuselage. Fortunately, the plane was able to lan… Read More
2024-01-12 10:00
In Chapter 2 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss log-log plots. Have you ever wondered who made the first log-log plot? The honor goes to French mathe… Read More
2024-01-05 10:00
Cell Mechanics.In Chapter 1 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss ideal solids and ideal liquids. Ideal solids are covered in Section 1.10, which introd… Read More
2023-12-29 10:00
Electricity and Magnetism,by Edward Purcell.In Intermediate Physics for Medicine and Biology, Russ Hobbie and I rarely discuss special relativity. We briefly mention that magnetism is a con… Read More
2023-12-22 10:00
A few weeks ago, I published a blog post about the television show Meeting of Minds. That show from the late 1970s was created and hosted by Steve Allen and featured historical figures as gu… Read More
2023-12-15 10:00
Thermodynamics is often summarized in three laws. Do Russ Hobbie and I discuss the three laws of thermodynamics in Intermediate Physics for Medicine and Biology? Yes!
The First Law
We state… Read More
2023-12-08 10:00
One Hot Summer,by Rosemary Ashton.I recently finished Rosemary Ashton’s book One Hot Summer: Dickens, Darwin, Disraeli, and the Great Stink of 1858. Her prologue begins
What was it lik… Read More
2023-12-01 10:00
Louis Pasteur (1822–1895)One recurring theme in this blog is how scientists make the transition from working in the physical sciences to studying the biological sciences. Indeed, this… Read More
2023-11-24 10:00
The Deadly Rise of Anti-Science,by Peter Hotez.This week I read The Deadly Rise of Anti-Science: A Scientist’s Warning, by Peter Hotez. Every American should read this book. In his int… Read More
2023-11-17 10:00
An antiscatter grid.Episcophagus, CC BY-SA 4.0, via Wikimedia Commons.In Chapter 16 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss the antiscatter grid used in r… Read More
2023-11-10 10:00
When my wife and I were in Paris several years ago we visited the Musée de l’Orangerie, where Claude Monet’s beautiful water lily murals are displayed. Monet (1840–1… Read More
2023-11-03 09:00
Last week I introduced the Helmholtz coil and the Maxwell coil. The Maxwell coil is useful for creating the magnetic field gradient needed for magnetic resonance imaging. At the end of the p… Read More
2023-10-27 09:00
To do magnetic resonance imaging, you need a static magnetic field that is uniform and a switchable magnetic field that has a uniform gradient. How do you produce such fields? In this post… Read More
2023-10-20 09:00
A teacher affects eternity; he can never tell where his influence stops. Henry Adams
Stephen Clough, from the 1975Homestead Jr.-Sr. High School Yearbook.How does someone end up being… Read More
2023-10-13 09:00
J. Robert Oppenheimer.Did you watch Oppenheimer in the theater this summer? I did. The movie told how J. Robert Oppenheimer led the Manhattan Project that built the first atomic bomb during… Read More
2023-10-06 09:00
In Chapter 14 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss the risk of DNA damage—and therefore cancer—caused by ultraviolet light from the sun. Fi… Read More
2023-09-29 09:00
In Chapter 2 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss the problem of decay plus input at a constant rate.
Suppose that in addition to the removal of y fro… Read More
2023-09-22 09:00
In Chapter 2 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss semilog plots, where the vertical axis is marked using a logarithmic scale. In this case, a constant… Read More
2023-09-15 09:00
An episode of Meeting of Minds, with (l-r) Atilla the Hun, Emily Dickinson, host Steve Allen, Charles Darwin, and Galileo Galilei. When I was a teenager, one of my favorite shows was Me… Read More
2023-09-08 09:00
Ten years ago yesterday, on September 7, 2013, Physicist Albert Bartlett died at the age of 90. Russ Hobbie and I mentioned Bartlett in Chapter 2 of Intermediate Physics for Medicine and Bio… Read More
2023-09-01 09:00
When listening to NBC Nightly News on August 24, I heard Lester Holt discuss Japan’s plan to release into the Pacific Ocean treated wastewater from the Fukushima nuclear power plant, t… Read More
2023-08-25 09:00
In Intermediate Physics for Medicine and Biology, Russ Hobbie and I don’t talk about homeopathy (thank goodness!). A homeopathic medicine is one that has been diluted with water multip… Read More
2023-08-18 09:00
Paul Maccabee (1944–2023).Photo used with permission from theDownstate Health Sciences University website.My friend and collaborator Paul Maccabee died on April 24. Paul was a pioneer… Read More
2023-08-11 09:00
Congress is currently considering the “Connect Our Parks Act.” It is
a bill to require the Secretary of the Interior to conduct an assessment to identify locations in National Pa… Read More
2023-08-04 09:00
This Sunday is the 120th anniversary of the birth of American physicist Philip Morse (1903–1985). Russ Hobbie and I mention Morse in Chapter 13 of our book Intermediate Physics for Med… Read More
2023-07-28 09:00
John Moulder, from Khurana et al. (2008) Med. Phys., 35:5203, with permission from Wiley.John Moulder, a leading expert in radiation biology, died about a year ago (on July 17, 2022; I wasn… Read More
2023-07-21 09:00
Today I want to talk to high school students who, when they attend college, might be majoring in biological physics. What does a biological physics major look like? Below I present my vision… Read More
2023-07-14 09:15
Want a short course in vector calculus? You can find one in Intermediate Physics for Medicine and Biology.
Divergence
The divergence is defined in Section 4.1 in IPMB, when discussing the… Read More
2023-07-07 09:00
Have you ever been reading a book, making good progress with everything making sense, and then you suddenly stop at say “wait… what?”. That happened to me recently as I wa… Read More
2023-06-30 09:00
The Age of Napoleon, by Will and Ariel Durant,Volume 11 of The Story of Civilization.Regular readers of this blog may recall that over the last few years I’ve been reading Will and Ari… Read More
2023-06-23 09:00
Any good undergrad statistical mechanics class analyzes the partition function. However, Russ Hobbie and I don’t introduce the partition function in Intermediate Physics for Medicine a… Read More
2023-06-16 09:00
Gene Surdutovich and I are hard at work on the 6th edition of Intermediate Physics for Medicine and Biology. So far, the main thrust of our work involves LaTeX and Mathematica.Russ Hobbie an… Read More
2023-06-09 09:05
Hanson, L., “Is Quantum Mechanics Necessary for Understanding Magnetic Resonance?”Concepts Magn.Reson., 32:329–340, 2008In Chapter 18 of Intermediate Physics for Medicine a… Read More
2023-06-02 09:00
Intermediate Physics for Medicine and Biology assumes the reader knows calculus. Most medical doctors and biologists have studied some calculus, but I’m not sure they remember much of… Read More
2023-05-26 09:00
A Paramecium aurelia seen through an optical microscope. Source: Wikipedia (http://en.wikipedia.org/wiki/Image:Paramecium.jpg)Homework Problem 28 at the end of Chapter 2 in Intermediate Phys… Read More
2023-05-19 09:00
Breathless, by David Quammen.Whenever David Quammen has a new book, I put it on my “to read” list. Recently I finished his latest: Breathless: The Scientific Race to Defeat a Dea… Read More
2023-05-12 09:00
King Charles III of England was
crowned this week. What’s that got to do with Intermediate Physics for Medicine and Biology? Well, the king is a big supporter of alternative medicine… Read More
2023-05-05 09:09
Thank you for your interest in the 5th edition of Intermediate Physics for Medicine and Biology. We’re considering a 6th edition and we would like to get your opinions and input. Some… Read More
2023-04-28 09:00
Roth, B. J., 2023, Biomagnetism: The first sixty years. Sensors, 23:4218.
The last two blog posts have dealt with biomagnetism: the magnetic fields produced by our bodies. Some of you might… Read More
2023-04-21 09:00
When I was on the faculty at Vanderbilt University, my student Marcella Woods and I examined the magnetic field produced by electrical activity in a sheet of cardiac muscle. I really like th… Read More
2023-04-14 09:00
One of the key limitations of the magnetoencephalogram (MEG) is that it’s not sensitive to a radial dipole. What does this mean? The MEG is the magnetic field outside the head produced… Read More
2023-04-07 09:00
For three years I’ve dodged the bullet, but no more; I have covid. I’m doing fine, thank you. For me the symptoms were similar to a moderate cold. My doctor put me on a five-day… Read More
2023-03-31 09:00
Exclamation points are rare in scientific writing, but I like them. Occasionally Russ Hobbie and I use them in Intermediate Physics for Medicine and Biology. They’re fine as long as yo… Read More
2023-03-24 09:00
Over the last couple years, I’ve been writing lots of review articles. In the last few weeks three have been published. All of them are open access, so you can read them without a subs… Read More
2023-03-17 13:22
Why Should We Abolish Daylight Saving Time? J. Biol. Rhythms, 34:227–230, 2019. Last Sunday, we all switched from standard time to daylight saving time, losing an hour of sl… Read More
2023-03-10 10:00
I’m a fan of Dianna Cowern, better known as Physics Girl, who makes Youtube videos about physics that would be helpful for readers of Intermediate Physics for Medicine and Biology. Thr… Read More
2023-03-03 10:00
Cobalt Blues,by Peter Almond.I recently read Cobalt Blues: The Story of Leonard Grimmett, the Man Behind the First Cobalt-60 Unit in the United States (Springer, 2013), written by Peter Almo… Read More
2023-02-24 13:51
To understand biological physics, you must know the properties of water. In Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss water’s density, compressibility, v… Read More
2023-02-24 10:08
In Problem 14 of Chapter 7 in Intermediate Physics for Medicine and Biology, Russ Hobbie and I chose a strange-looking function to represent the intracellular potential along a nerve axon, v… Read More
2023-02-17 10:00
Abe Liboff, in hisoffice at Oakland UniversityOakland University physicist Abe Liboff died recently. A notice from President Ora Hirsch Pescovitz, published on the OU website, stated: It is… Read More
2023-02-10 11:33
Fifty Outstanding Medical Physicists. In 2014, to mark its 50th anniversary, the International Organization for Medical Physics published a list of 50 medical physicists who have made an out… Read More
2023-02-03 10:00
Bust of Félix Savartin the Institut de France.From Wikipedia. I’m fascinated by scientists who make the transition from medicine to physics, which is the opposite of… Read More
2023-01-27 10:00
Alexander PopeI mentioned before in this blog that I’m reading Will and Ariel Durant’s eleven-volume masterpiece The Story of Civilization. Recently, in Volume Nine about The Age… Read More
2023-01-20 10:00
The Invisible Rainbow,by Arthur Firstenberg.Over Christmas break, I read The Invisible Rainbow: A History of Electricity and Life, by Arthur Firstenberg. What can I say about such a book? Fi… Read More
2023-01-13 10:00
Physics,by Halliday and Resnick.Robert Resnick, physics textbook author extraordinaire, was born 100 years ago last Wednesday (January 11, 1923). A Rensselaer Polytechnic Institute website s… Read More
2023-01-06 10:00
Edith Anne StoneyToday is Edith Anne Stoney’s birthday; she was born on January 6, 1869. In an article that appeared in the December, 2013 issue of Scope (the quarterly magazine of the… Read More
2022-12-30 10:00
When I worked at the National Institutes of Health, I studied transcranial magnetic stimulation. In Chapter 8 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I describe thi… Read More
2022-12-23 10:00
I encourage students to build their qualitative problem solving skills by recasting equations in dimensionless variables, analyzing the limiting behavior of mathematical expressions, and ske… Read More
2022-12-16 10:00
Mark HallettLast Monday I attended (over the internet) a Festschrift to honor the retirement of Mark Hallett from the intramural program at the National Institutes of Health. Russ Hobbie and… Read More
2022-12-09 10:00
Air and Water,by Mark Denny.In Intermediate Physics for Medicine and Biology, Russ Hobbie and I don’t talk much about surface tension. However, in Air and Water, Mark Denny devotes sev… Read More
2022-12-02 10:00
When discussing the attenuation of sound in Intermediate Physics for Medicine and Biology, Russ Hobbie and I write In acoustics, the attenuation is usually expressed in decibels per meter. A… Read More
2022-11-25 10:00
In Section 14.4 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss molecular energy levels. In particular, we examine translational, rotational, and vibrational leve… Read More
2022-11-18 10:00
Forever and Ever, Amen,by Randy Travis.I’m a big fan of country music. After all, I was a graduate student in Music City: Nashville. I used to ride my bike down to 16th Avenue by the o… Read More
2022-11-11 10:00
The Eighth Day of Creation, by Horace Freeland Judson.In Intermediate Physics for Medicine and Biology, Russ Hobbie and I analyze the role physics plays in the biological sciences. What is t… Read More
2022-11-04 09:00
The poster for the 2022 International Day of Medical PhysicsMonday, November 7, is the International Day of Medical Physics. The purpose of this annual event, organized by the International… Read More
2022-10-28 09:00
In Chapter 1 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I introduce a concept from fluid dynamics called the boundary layer. The behavior of a sphere moving through a… Read More
2022-10-21 09:00
If you shine x-rays through a material and measure the number absorbed by it, you create an x-ray absorption spectrum. The absorption is related to the cross section; the bigger the cross se… Read More
2022-10-14 09:00
The Art of Electronics,by Horowitz and Hill.Nine years ago I wrote in this blog about the second edition of Horowtiz and Hill’s textbook The Art of Electronics. At the end of that post… Read More
2022-10-07 09:00
The Last Man Who Knew Everything,by Andrew Robinson.Almost ten years ago in this blog, I speculated about who was the greatest biological physicist of all time, and suggested that it was the… Read More
2022-09-30 09:00
Grimes DR (2021) Radiofrequency Radiation and Cancer, JAMA Oncology, 8:456–461.In my book Are Electromagnetic Fields Making Me Ill? I discussed the danger of cell phone radiation. Rece… Read More
2022-09-23 09:00
This week I belatedly learned that Mike Joy died. This was sad news indeed. Joy was a Canadian electrical engineer who measured current density in the body using magnetic resonance imaging… Read More
2022-09-16 09:00
Drawdown,Edited by Paul Hawken.This blog is about physics applied to medicine and biology, but if we don’t solve the climate crisis there’s no use developing fancier ways to do m… Read More
2022-09-09 09:00
“Earth teems with sights and textures, sounds and vibrations, smells and tastes, electric and magnetic fields. But every animal can only tap into a small fraction of reality’s fu… Read More
2022-09-02 09:00
A homework problem in Chapter 14 of Intermediate Physics for Medicine and Biology states Problem 28. Integrate Eq. 14.33 over all wavelengths to obtain the Stefan-Boltzmann law, Eq. 14.34. Y… Read More
2022-08-26 09:00
When I was at the National Institutes of Health in the early 1990s, I worked on transcranial magnetic stimulation of the brain. In Chapter 8 of Intermediate Physics for Medicine and Biology… Read More
2022-08-19 09:00
In Table 13.1 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I list the approximate intensity levels of various sounds, in decibels. The minimum perceptible sound is 0 dB… Read More
2022-08-12 09:00
Scientist: E. O. Wilson: A Life in Nature,by Richard Rhodes.I often become interested in the writing of a particular author and read several of that author’s books consecutively. Recen… Read More
2022-08-05 09:00
In Chapter 2 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I have an end-of-chapter homework problem about consuming a finite resource. Section 2.10 Problem 37. The… Read More
2022-07-29 09:00
Essential Concepts in MRI,by Yang Xia.Suppose you’ve read Chapter 18 of Intermediate Physics for Medicine and Biology covering magnetic resonance imaging and you want to learn more. Wh… Read More
2022-07-22 09:00
In radiotherapy, a dose of radiation is usually not given all at once, but instead is applied in fractions. In Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss fracti… Read More
2022-07-15 09:00
Screenshot of the websiteMedical Physics for World Benefit,www.mpwb.org.In the last two blog posts (here and here), I discussed the book True Tales of Medical Physics, edited by Jacob Van Dy… Read More
2022-07-08 12:07
The Physics of Radiology,by Johns and Cunningham.In last week’s blog post, I reviewed the recently published book True Tales of Medical Physics. A point I didn’t mention in my re… Read More
2022-07-01 09:00
True Tales of Medical Physics:Insights into a Live-Saving Specialty,by Jacob Van Dyk.I’ve found the perfect book for readers of Intermediate Physics for Medicine and Biology who are fa… Read More
2022-06-24 09:00
One of the most important parameters in thermodynamics is the specific heat capacity. In Chapter 3 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I define the specific hea… Read More
2022-06-17 09:00
In Chapter 1 of Intermediate Physics for Medicine and Biology, Russ Hobbie and I discuss biomechanics. One of our most important examples is the force on the hip. The forces in the hip joint… Read More
2022-06-10 09:00
In Appendix H of Intermediate Physics for Medicine and Biology, Russ Hobbie and I briefly mention the severe lung disease cystic fibrosis. Analyzing this disease provides an opportunity to e… Read More
2022-06-03 09:00
The Story of Civilization,by Will and Ariel Durant.About a year ago I began reading the eleven-volume series The Story of Civilization by Will and Ariel Durant. I just finished Volume 4, The… Read More
Subscribe to Intermediate Physics For Medicine And Biology
Get updates delivered right to your inbox!