How to use an Oxford Nanopore MinION to extract DNA from river water and determine which bacteria live in it External links to this page Updated 2025-07-16
- 2021-03-25: Oxford Nanopore Technologies retweeted this article, that's awesome!
- 2021: hackaday.com/author/wd5gnr1/ "SEQUENCING DNA FOR METAGENOMICS" by Al Williams (2021). This came after Ciro Santilli self promoted at: stackoverflow.blog/2021/02/03/sequencing-your-dna-with-a-usb-dongle-and-open-source-code/#comment-1411921
sqlite3 Node.js package Updated 2025-07-16Includes its own copy of sqlite3, you don't use the system one, which is good to ensure compatibility. The version is shown at: github.com/mapbox/node-sqlite3/blob/918052b538b0effe6c4a44c74a16b2749c08a0d2/deps/common-sqlite.gypi#L3 SQLite source is tracked compressed in-tree: github.com/mapbox/node-sqlite3/blob/918052b538b0effe6c4a44c74a16b2749c08a0d2/deps/sqlite-autoconf-3360000.tar.gz horrendous. This explains why it takes forever to clone that repository. People who don't believe in git submodules, there's even an official Git mirror at: github.com/sqlite/sqlite
It appears to spawn its own threads via its C extension (since JavaScript is single threaded and and SQLite is not server-based), which allows for parallel queries using multiple threads: github.com/mapbox/node-sqlite3/blob/v5.0.2/src/threading.h
Hello world example: nodejs/node-sqlite3/index.js.
As of 2021, this had slumped back a bit, as maintainers got tired. Unmerged pull requests started piling more, and
better-sqlite3 Node.js package started pulling ahead a little.- github.com/mapbox/node-sqlite3/issues/1381
FATAL ERROR: Error::ThrowAsJavaScriptException napi_throwwith Node.jsworker_threadsvsbetter-sqlite3Node.js package github.com/JoshuaWise/better-sqlite3/issues/237
better-sqlite3 Node.js package Updated 2025-07-16 Nick Leeson and the Fall of the House of Barings by Adam Curtis (1996) Updated 2025-07-16
Oxford Master Course in Mathematical and Theoretical Physics Updated 2025-07-16
Giant-impact hypothesis Updated 2025-07-16
Isomer Updated 2025-07-16
Isomers were quite confusing for early chemists, before atomic theory was widely accepted, and people where thinking mostly in terms of proportions of equations, related: Section "Isomers suggest that atoms exist".
Ultra High Frequency Updated 2025-07-16
Microwave source Updated 2025-07-16
Microwave only found applications into the 1940s and 1950s, much later than radio, because good enough sources were harder to develop.
One notable development was the cavity magnetron in 1940, which was the basis for the original radar systems of World War II.
Microwave transmission Updated 2025-07-16
Microwave oven Updated 2025-07-16
How Microwaves Work by National MagLab (2017)
Source. A bit meh. Does not mention the word cavity magnetron! Mars sample-return mission Updated 2025-07-16
Human mission to Mars Updated 2025-07-16
Exception to the Madelung energy ordering rule Updated 2025-07-16
lujakob/nestjs-realworld-example-app SQLite port Updated 2025-07-16
Tried a quick port to SQLite to get rid of annoying local databases for development, but failed, at c1c2cc4e448b279ff083272df1ac50d20c3304faandthen:fails with:Attempt to hack it:and after that it seems to run.
npm install sqlite3 --save-dev{
"type": "sqlite",
"database": "db.sqlite3",
"entities": ["src/**/**.entity{.ts,.js}"],
"synchronize": true
}npm startDataTypeNotSupportedError: Data type "timestamp" in "ArticleEntity.created" is not supported by "sqlite" database.--- a/src/article/article.entity.ts
+++ b/src/article/article.entity.ts
@@ -20,10 +20,10 @@ export class ArticleEntity {
@Column({default: ''})
body: string;
- @Column({ type: 'timestamp', default: () => "CURRENT_TIMESTAMP"})
+ @Column({ default: () => "CURRENT_TIMESTAMP"})
created: Date;
- @Column({ type: 'timestamp', default: () => "CURRENT_TIMESTAMP"})
+ @Column({ default: () => "CURRENT_TIMESTAMP"})
updated: Date;I can signup and login, terrible error reporting as usual, make sure to use long enough usernames/passwords.
However, article creation fails with:
Unhandled Rejection (TypeError): Cannot read property 'slug' of undefined Essential metabolism for a minimal cell (2019) Updated 2025-07-16
Fabry-Pérot interferometer Updated 2025-07-16
Fabry Perot Interferometer by JFC UCL (2016)
Source. Description only, reasonable animations. Considers the case of two nearby beam splitters.Fabry-Perot Introduction by Williams College Physics (2020)
Source. Shows a working device. Confocal optical cavity, one of the mirrors scans back and forward moved by a piezoelectric motor, this is called a "scanning Fabry-Perot interferometer".
Does not produce an interference pattern, only an on/off blob, which is then fed into an oscilloscope for analysis. The oscilloscope shows both the mirror displacement (which is given by a voltage) and the light detector output.
Mach-Zehnder interferometer Updated 2025-07-16
Faraday effect Updated 2025-07-16
Fluorescent lamp Updated 2025-07-16
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