The book is a bit slow until Charles K. Kao comes along, then it gets exciting.
Very low frequency by Ciro Santilli 40 Updated 2025-07-16
Notably used for communication with submarines, so in particular crucial as part of sending an attack signal to that branch of the nuclear triad.
María del Pilar Díaz could refer to various individuals or contexts, as it is a relatively common name in Spanish-speaking countries. Without additional context, it's difficult to provide a specific answer. The name could refer to a public figure, academic, artist, or someone else in a specific field.
Microwave oven by Ciro Santilli 40 Updated 2025-07-16
Video 1.
How Microwaves Work by National MagLab (2017)
Source. A bit meh. Does not mention the word cavity magnetron!
Video 2. . Source. Cool demonstration of the standing waves in the cavity with cheese!
This is an extremely widely used technique as of 2020 and much earlier.
If allows you to amplify "any" sequence of choice (TODO length limitations) between a start and end sequences of interest which you synthesize.
If the sequence of interest is present, it gets amplified exponentially, and you end up with a bunch of DNA at the end.
You can then measure the DNA concentration based on simple light refraction methods to see if there is a lot of DNA or not in the post-processed sample.
One common problem that happens with PCR if you don't design your primers right is: en.wikipedia.org/wiki/Primer_dimer
Sometime it fails: www.reddit.com/r/molecularbiology/comments/1kouomw/when_your_pcr_fails_again_and_you_start/
Nothing humbles you faster than a bandless gel. One minute you’re a scientist, the next you’re just a pipette-wielding wizard casting spells that don’t work. Meanwhile, physicists are out there acting like gravity always behaves. Smash that upvote if your reagents have ever gaslit you.
and a comment:
PCR = Pray, Cry, Repeat
Hybrid mail is a service that combines traditional postal mail and digital communication technologies. It allows users to prepare and send mail through digital means that are then printed, processed, and delivered by a postal service. Here's how it typically works: 1. **Digital Document Creation**: Users create a document, letter, or mail item using digital tools, such as word processors or specific hybrid mail software.
IMail is an email server software developed by IMail Communications (now a part of the team at Cypoint). It provides email hosting capabilities and features for businesses and organizations. IMail offers functionalities such as: 1. **Email Hosting**: It can host email for domains and provide services like sending, receiving, and managing emails.
The London Action Plan is a strategic framework aimed at addressing issues related to international crime, particularly in the context of online fraud and scams. While there are different initiatives and frameworks with similar names, the term is most commonly associated with efforts to enhance cooperation among law enforcement agencies, industry stakeholders, and governments to combat the growing threat of cybercrime through coordinated action.
A suppression list is a compilation of contacts or identifiers that should be excluded from certain communications or marketing efforts. These lists are typically used in email marketing, advertising, and other forms of outreach to prevent messages from being sent to recipients who have opted out, unsubscribed, or should not be included for various reasons.
RelayOne is a platform designed to enhance communication and workflow efficiency, particularly in business settings. It focuses on integrating various communication channels, such as messaging, emails, and calls, into a single interface. By doing so, RelayOne aims to streamline operations and improve collaboration among teams. The platform often includes features like task management, real-time collaboration tools, and analytics to help organizations monitor performance and communication effectiveness.
SpamBayes is an open-source statistical email classifier that is designed to filter out unwanted email, commonly known as spam. Developed using the Python programming language, SpamBayes employs a Bayesian filtering algorithm to analyze the content of incoming emails and determine the likelihood that a message is spam based on statistical probabilities derived from previously classified emails.
A virus hoax is a false or misleading claim about a computer virus, worm, or other types of malware that spreads through communication channels like email or social media. These hoaxes typically warn users about an imminent threat, often exaggerating the dangers or claiming that simply reading a message could infect their computer. Common elements of virus hoaxes include: 1. **False Claims**: They often provide alarming details about a virus that does not actually exist or has been exaggerated.
Empirical sociology is a branch of sociology that focuses on the collection and analysis of data derived from direct observation or experimentation to understand social phenomena. This approach is grounded in the belief that sociological theories and concepts should be tested and validated through empirical evidence, rather than solely relying on theoretical constructs. Key characteristics of empirical sociology include: 1. **Data Collection**: Empirical sociology uses various research methods to gather data, including surveys, interviews, observations, and experiments.
Molyneux's problem is a philosophical thought experiment concerning the nature of perception and the distinction between different senses, particularly vision and touch. It was first posed by the Irish philosopher William Molyneux in a letter to John Locke in the late 17th century. The problem can be summarized as follows: Imagine a person who has been blind from birth and who has developed the ability to touch and differentiate shapes through their sense of touch.

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 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . 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.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  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