Ciro Santilli @cirosantilli 37

This section is about telecommunication systems that are based on top of telephone lines.

Telephone lines were ubiquitous from early on, and many technologies used them to send data, including much after regular phone calls became obsolete with VoIP.

These market forces tended to eventually crush non-telephone-based systems such as telex. Maybe in that case it was just that the name sounded like a thing of the 50's. But still. Dead.

The first working one in 1947 by John Bardeen and walter Brattain in Bell Labs Murray Hill.

People had already patented a lot of stuff before without being able to make them work. Nonsense.

As the name suggests, this is not very sturdy, and was quickly replaced by bipolar junction transistor.

The perfect Middle Way between command-line interfaces and GUIs. A thing of great beauty.

Basically mean that parallel evolution happened. Some cool ones:

TODO understand this stuff:

2023 full connectome published on Science by Marta Zlatic's lab at the MRC:

The hard part then is how to make any predictions from it:

2024: www.nature.com/articles/d41586-024-03190-y Largest brain map ever reveals fruit fly's neurons in exquisite detail

As of 2022, it had been almost fully decoded by post mortem connectome extraction with microtome!!! 135k neurons.

That article mentions the humongous paper elifesciences.org/articles/66039 elifesciences.org/articles/66039 "A connectome of the Drosophila central complex reveals network motifs suitable for flexible navigation and context-dependent action selection" by a group from Janelia Research Campus. THe paper is so large that it makes eLife hang.

The exact format of table entries is fixed by the hardware.

Each page entry can be seen as a struct with many fields.

The page table is then an array of struct.

On this simplified example, the page table entries contain only two fields:so in this example the hardware designers could have chosen the size of the page table to b 21 instead of 32 as we've used so far.

All real page table entries have other fields, notably fields to set pages to read-only for Copy-on-write. This will be explained elsewhere.

It would be impractical to align things at 21 bits since memory is addressable by bytes and not bits. Therefore, even in only 21 bits are needed in this case, hardware designers would probably choose 32 to make access faster, and just reserve bits the remaining bits for later usage. The actual value on x86 is 32 bits.

Here is a screenshot from the Intel manual image "Formats of CR3 and Paging-Structure Entries with 32-Bit Paging" showing the structure of a page table in all its glory: Figure 1. "x86 page entry format".

The fields are explained in the manual just after.

Ciro Santilli supports full legalization of all drugs, because he feels that it would be better overall for the world to have cheaper drugs and more drug addicts, but way, way less organized crime.

These should be extremely controlled of course, with extremely high taxes that puts their price just below the current illegal market, and a complete ban on any positive advertising.

Ciro believes that maybe the government could even go as far as giving free drugs to drug addicts so they don't have to rob to get a fix.

This is notably considering that drug-led organized crime completely dominates and corrupts the politics of many production and trafficking zones, which are already generally poor fucked up places to start with:Ciro's experiences in Brazil such as mentioned at São Remo, the favela next to USP, although much less extreme than the above, also come to mind.

Drug traffic corrupts everything. It prevents development of honest people. It is a cancer, which we have failed time and time a gain to cure. The only cure is to accept the other less insidious of addiction.

Bibliography:

Dual vectors are the members of a dual space.

In the context of tensors , we use raised indices to refer to members of the dual basis vs the underlying basis:The dual basis vectors $e^i$ are defined to "pick the corresponding coordinate" out of elements of V. E.g.:By expanding into the basis, we can put this more succinctly with the Kronecker delta as:

Note that in Einstein notation, the components of a dual vector have lower indices. This works well with the upper case indices of the dual vectors, allowing us to write a dual vector $f$ as:

In the context of quantum mechanics, the bra notation is also used for dual vectors.

Bibliography:

ChatGPT produces:Omid Kordestani - Joined in 1999 as Google’s first business hire, focusing on sales and revenue generation.

The conventional starting point is not at the E. Coli K-12 MG1655 origin of replication.

biocyc.org/ECOLI/NEW-IMAGE?type=EXTRAGENIC-SITE&object=G0-10506 explains:If it is a bit hard to understand what they mean by "origin of transfer" though, as that term is usually associated with the origin of transfer of bacterial conjugation.

NCBI taxonomy entry: www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=511145 This links to:

KEGG entry: www.genome.jp/pathway/eco01100+M00022

BioCyc promoter database query URL: biocyc.org/group?id=:ALL-PROMOTERS&orgid=ECOLI

All gene names that start with an Y such as:appear to be proteins of unknown function.

UniProt for example describes YaaX as "Uncharacterized protein YaaX".

As function is discovered, they then change it to a better name, e.g. to names such as the E. Coli K-12 MG1655 transcription unit thrLABC proteins all of which have a clear name due to threonine.

There are many other y??? as of 2021! Though they do tend to be smaller molecules.

20 minutes in optimal conditions, with a crazy multiple start sites mechanism: E. Coli starts DNA replication before the previous one finished.

Otherwise, naively, would take 60-90 minutes just to replicate and segregate the full DNA otherwise. So it starts copying multiple times.

Given a function $f$:we want to find the points $x$ of the domain of $f$ where the value of $f$ is smaller (for minima, or larger for maxima) than all other points in some neighbourhood of $x$.

In the case of Functionals, this problem is treated under the theory of the calculus of variations.