The Eighth Day of Creation by Ciro Santilli 37 Created 2025-01-27 Updated 2025-07-16
The author Horace Freeland Judson was a MacArthur fellow, no wonder he found the time to write this bible!
Max Delbrück is quoted as saying:
So in retrospect what the denouement was, was that both the principle of replication and the principle of readout are DNA very simple, and the actual machinery for doing it is immensely complex. That's the way it has turned out."
Nice way to put it.
When Thomas F. Anderson had started taking and publishing the first phage electron microscope images:
Now, Anderson later wrote, "We could really see the phage as tadpole­ shaped particles, whose heads ranged from 600 to 800 A [...] Anderson wrote. "I remember particularly the reaction of Alfred Hershey's teacher, kindly old Professor J. J. Bronfenbrenner, who had worked on bacteriophages for many years at Washington University in St. Louis. ... When he first saw our pictures ... he clapped the palm of his hand to his forehead and exclaimed, 'Mein Gott! They've got tails!'"
Nice quote from Pauling's Nobel Prize speech highlighting the power and required accuracy of chemical ball and stick models:
The requirements are stringent ones. [...]. In order that the principles of modem structural chemistry may be applied with the power that their reliability justifies, molecular models must be constructed with great accuracy. For example, molecular models on the scale of 2.5 cm 1 angstrom unit, have to be made with a precision better than 0.01 cm.
Image software by Ciro Santilli 37 Created 2025-01-27 Updated 2025-07-16
Home by Anthony Morphy 0 Created 2025-01-25 Updated 2025-04-18
Welcome to my home page!
Ion Selective Electrodes / Response of the Glass Electrode by pioyi 6 Created 2025-01-25 Updated 2025-04-18
The hydrated glass interface is conductive due to the presence of hydrogen cations.
In each interface of the membrane an equilibrium is established:
A potential difference is again caused due to the difference in ionization.
The equilibrium's position depends on the concentration of in each interface.
Ion Selective Electrodes / Hydration of Glass by pioyi 6 Created 2025-01-25 Updated 2025-04-18
Before using the glass electrode, one must assure that it is hydrated. During hydration, single charged cations that are loosely placed in the glass lattice are overwhelmingly exchanged by hydrogen cations.
Electrochemical Methods: Fundamentals and Applications, 2nd Edition Allen J. Bard, Larry R. Faulkner.
Principles of Instrumental Analysis 6th Edition by Douglas A. Skoog
Ion Selective Electrodes / Glass Electrode by pioyi 6 Created 2025-01-25 Updated 2025-04-18
Glass Electrodes make use of the ion-selective properties of glass and are used today in pH measurements.
The indicator electrode consists of a thin glass membrane that is contained inside a thick-walled glass or plastic tube. Inside the tube, there exists a solution of HCl (0.1M) satured with AgCl together with a silver wire. This is an internal Ag/AgCl reference electrode. The indicator electrode is connect with another refenrece electrode (the external one) and thus the cell is complete.
Ion Selective Electrodes / General Characterization by pioyi 6 Created 2025-01-25 Updated 2025-04-18
There are many types of ion-selective electrodes (often abbreviated as ISEs) whose design greatly varies. Nevertheless they are all based on the same principle: The membrane potential.
A membrane is any continuous layer made of a semi-permeable material, that separates two solutions. The membrane's characteristics cause the appearance of a membrane potential across the two solutions.
The membrane potential exists, due to the concentration difference (more accurately, activity difference) of the two solutions. Compounds from the denser mixture will diffuse through the membrane to the dilute solution, thus giving rise to a potential difference adjacent to the membrane. The present potential field opposes the movement caused by the diffusion, and a dynamic equilibrium is eventually established.
The membrane potential that is established due to this equilibrium can be calculated via the Nernst equation:
, where and refer respectively to the activity of the compound of interest in the sample solution and in a standard/reference solution.
The role of the standard/reference solution is to contain a constant activity of the compound to be measured, therefore making it possible to solve the Nernst equation for the unknown .
The membrane is just a component of the two electrode cell, and we obtain useful data by measuring the potential difference across the whole cell.
Ion Selective Electrodes by pioyi 6 Created 2025-01-25 Updated 2025-04-18
An ion-selective electrode is an electrochemical sensor based on thin films or selective membranes as recognition elements.
They are the most commonly used types of indicator electrodes (electrodes in which the analyte is being studied/measured) in potentiometric measurements due to their accuracy, selectivity and fast response time compared to metallic ones.
Hackathon by Ciro Santilli 37 Created 2025-01-22 Updated 2025-07-16
Hackathons are useless.
If you have a useful project, why would you ever restrict its development to a specific timeframe and with a specific set of contributors?
Just put your project on GitHub and promote it to try and get users and contributors instead!
Instead of announcing organizing hackathons, people should just curate forums where people with similar interests can talk to one another instead, to find new projects that might interest one another.
Restricting intensive development to a few days tends to produce crappy code and not reach real goals.
Ciro Santilli's hardware / Child bicycle trailer by Ciro Santilli 37 Created 2025-01-22 Updated 2025-07-16
First we got a Thule Chariot Cab two seater in our hands: www.thule.com/en-bg/bike-trailers/bike-trailers-for-kids/thule-chariot-cab-_-10204021 It's humongous, double seater only. Folded: 110 x 80 x 46 cm folded, 16.5 kg.
Thule Chariot Courier: www.thule.com/en-si/bike-trailers/bike-trailers-for-dog-and-cargo/thule-courier-_-10102001. This seems like an older version of the Cab. Folded: 99 x 74 x 32 cm. 16kg.
Thule Chariot Lite single: Folded: 87 x 65 x 37.5 cm. 11.7 kg.
Burley Honey Bee burley.com/en-in/products/honey-bee. Double only: folded: 96.3 x 74.2 x 22.6 cm. 13 kg. 500 pounds new on Amazon www.amazon.co.uk/Burley-Honey-Seat-Trailer-Stroller/dp/B0BW21V26L, a used one for sale at: www.facebook.com/marketplace/item/575427528791792/ for 125. Got my hands on a new one. Felt good. Definitely much cheaper build than the Thule Chariot Cab, but way smaller. Still a bit large for the shed, but at least it stands a chance!
Burley Bee: burley.com/en-in/products/bee. Single: folded 95.25 x 65.7 x 25.4 cm 9.8 kg. Double: folded: 10.2 kg. 95.2 x 74.6 x 26.4
Burley D'Lite X: burley.com/en-in/products/dlite-x Single: folded 91.4 x 69.9 x 38.1 cm 12.5 kg. Double: folded 94 x 79.4 x 36.2 cm 13.8 kg.
Hamax Outback: www.hamax.com/kid/bike-trailer/outback-bike-trailer-2-seats Double: 20 kg folded size: does not say.
Software Guard Extensions by Ciro Santilli 37 Created 2025-01-21 Updated 2025-07-16
The hole point of Intel SGX is to allow users to be certain that a certain code was executed in a remove server that they rent but don't own, like AWS. Even if AWS wanted to be malicious, they would still not be able to modify your read your input, output nor modify the program.
The way this seems to work is as follows.
Each chip has its own unique private key embedded in the chip. There is no way for software to read that private key, only the hardware can read it, and Intel does not know that private key, only the corrsponding public one. The entire safety of the system relies on this key never ever leaking to anybody, even if they have the CPU in their hands. A big question is if there are physical forensic methods, e.g. using electron microscopes, that would allow this key to be identified.
Then, using that private key, you can create enclaves.
Once you have an enclave, you can load a certain code to run into the enclave.
Then, non-secure users can give inputs to that enclave, and as an output, they get not only the output result, but also a public key certificate based on the internal private key.
This certificates states:
  • given input X
  • program Y
  • produced output Z
and that can then be verified online on Intel's website, since they keep a list of public keys. This service is called attestation.
So, if the certificate is verified, you can be certain that a your input was ran by a specific code.
Additionally:
  • you can public key encrypt your input to the enclave with the public key, and then ask the enclave to send output back encrypted to your key. This way the hardware owner cannot read neither the input not the output
  • all data stored on RAM is encrypted by the enclave, to prevent attacks that rely on using a modified RAM that logs data
CPU feature by Ciro Santilli 37 Created 2025-01-21 Updated 2025-07-16
ChatGPT is killing Stack Overflow by Ciro Santilli 37 Created 2025-01-21 Updated 2025-07-16
ChatGPT and other LLMs have significantly reduced Stack Overflow usage.
Ciro Santilli believes that these tools basically solve all the brain-dead problems which newbies would ask, and easy rep seekers would reply to.
Also, because Ciro Santilli only goes for long term reputation, which often means hard questions, this shot his yearly reputation rankings up without him doing anything, because all the guys who answered easy questions were decimated.
This was followed by Stack Overflow attempting to immorally and likely illegally trying to restrict free access to its previously commendable data dumps:which people were using to train LLMs.
This can be very clearly seen by several metrics on Stack Exchange Data Explorer, e.g. Ciro Santilli noticed that very clearly at: Total reputation in Stack Overflow over time how activity has been steadily falling since 2020.
Related posts:
Video 1.
ChatGPT Vs. Stack Overflow Be Like by Mr. P Solver
. Source.
Number of unknown rationality by Ciro Santilli 37 Created 2025-01-21 Updated 2025-07-16
This section is about numbers that we don't know if they are rational or not.
Bibliography:
Irrational number by Ciro Santilli 37 Created 2025-01-21 Updated 2025-07-16

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 5. . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact