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Cake day: August 4th, 2023

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  • This is true for only red and green loght detecting proteins (opsins) - the blue opsin gene is on chromosome 7.

    The red and green detecting proteins have an interesting history in humans.

    Fish, amphibians, lizards and birds have 4 different opsins: for red, green, yellow and blue colours. And the blue opsin sees up into the ultra-violet. Most animals can see waaaay more colours in the world than we (or any mammal) can. So what happened that makes mammal vision so poor?

    It’s thought that all mammals descend from one or a few species of nocturnal mammal that survived the catastrophe that wiped out the dinosaurs at the end of the Cretaceous. The colour detecting cells (the cones) need a lot of light compared to ones that see in black-and-white (the rods) and therefore nocturnal animals frequently lose cones in favour of the more sensitive rods for better night vision. The mammals that survived the Cretaceous extinction had also lost the green and yellow opsins while keeping red and blue - basically the two different ends of the light spectrum.

    Consequently today most mammals still have only 2 opsins so your cat or dog is red-green colourblind.

    Why do humans see green? Probably because our monkey forebears, who lived in trees and ate leaves, needed to distinguish red leaves and red fruit (visible to birds) from the green background.

    But how did we bring back the green opsin? A whole section of the X chromosome (where the red opsin is coded) got duplicated in a dna copying mistake and then there were two genes for red opsins. As there are different alleles (versions), they could be selected for independently and so one red opsin drifted up the spectrum to be specific for green. So our green opsin is a completely different gene to the green opsin in fish, birds, etc. This kind of evolution happens a lot which is why, for example, there are many families of similar hormones like testosterone and estrogen. And steroids too.



  • All junior devs should read OCs comment and really think about this.

    The issue is whether is_number() is performing a semantic language matter or checking whether the text input can be converted by the program to a number type.

    The former case - the semantic language test - is useful for chat based interactions, analysis of text (and ancient text - I love the cuneiform btw) and similar. In this mode, some applications don’t even have to be able to convert the text into eg binary (a ‘gazillion’ of something is quantifying it, but vaguely)

    The latter case (validating input) is useful where the input is controlled and users are supposed to enter numbers using a limited part of a standard keyboard. Clay tablets and triangular sticks are strictly excluded from this interface.

    Another example might be is_address(). Which of these are addresses? ‘10 Downing Street, London’, ‘193.168.1.1’, ‘Gettysberg’, ‘Sir/Madam’.

    To me this highlights that code is a lot less reusable between different projects/apps than it at first appears.



  • It is terribly sad - they must live in a world of hurt.

    However so many of these people actively try to hurt LGBTQ+ and trans people by inciting hate and changing laws to harm the non-straight. In particular they have been preaching that being gay/trans equates to being a child molester. This is horrific and needs to stop. Exposing the hypocrisy is essential to reducing the harm they are inflicting to real people right now




  • You need at least two copies in two different places - places that will not burn down/explode/flood/collapse/be locked down by the police at the same time.

    An enterprise is going to be commissioning new computers or reformatting existing ones at least once per day. This means the bitlocker key list would need printouts at least every day in two places.

    Given the above, it’s easy to see that this process will fail from time to time, in ways like accicentally leaking a document with all these keys.





  • That was one of the original proposed mechanisms to explain how the (obviously false) autism was caused.

    But since then, since thiomersal was removed, other ‘causes’ and moral issues have been invented, including cells from abortions.

    The one that makes me laugh the most is that it’s terrible that the poor poor baby is exposed to so many illnesses (measles, mumps, rubella, polio, tetanus, notovirus, rotovirus and more) in such a short space of time, it’s no wonder the poor dear’s immune system is compromised. And then the same mother drops the kid off at daycare and exposes the poor dear to all those viruses and more - and live viruses at that.

    There is no bleeding logic, just feels. And they get so angry at the fake harm that medicine is causing, and simultaneously actually causing real harms to real people.


  • I don’t think that the anti-oop collective is attacking polymorphism or overloading - both are important in functional programming. And let’s add encapsulation and implementation hiding to this list.

    The argument is that OOP makes the wrong abstractions. Inheritance (as OOP models it) is quite rare on business entities. The other major example cited is that an algorithm written in the OOP style ends up distributing its code across the different classes, and therefore

    1. It is difficult to understand: the developer has to open two, three or more different classes to view the whole algorithm
    2. It is inefficient: because the algorithm is distributed over many classes and instances, as the algorithm runs, there are a lot of unnecessary calls (eg one method on one instance has to iterate over many instances of its children, and each child has to iterate over its children) and data has to pass through these function calls.

    Instead of this, the functional programmer says, you should write the algorithm as a function (or several functions) in one place, so it’s the function that walks the object structure. The navigation is done using tools like apply or map rather than a loop in a method on the parent instance.

    A key insight in this approach is that the way an algorithm walks the data structure is the responsibility of the algorithm rather than a responsibility that is shared across many classes and subclasses.

    In general, I think this is a valid point - when you are writing algorithms over the whole dataset. OOP does have some counterpoints encapsulating behaviour on just that object for example validating the object’s private members, or data processing for that object and its immediate children or peers.





  • Sorry for taking a long time to reply.

    with plain old binary fission cell division, how do you get both to divide at the same time, and give each cell one of the new organelles?

    An excellent question! Luckily it was answered in the paper. The researchers actually had a high resolution soft x-ray movie of cell division (ok, an exaggeration, they had a few micrographs showing the sequence). In the sequence, it showed how the organelles (including the novel N2 fixation one) undergoing division and each ‘child’ organelle ending up in different halves.

    Cell division is controlled in the cell by an amazing process:

    • 2 centres are created on opposite sides of the cell
    • Structures like tethers are built that connect each centre to each of the organelles (the nucleus, mitochondria and the N2 fixators). These are called microtubules
    • The microtubules then start shortening, pulling the organelles in two directions, separating them.

    The x-ray micrographs show that the N2 fixators are already integrated into this mitosis mechanism - my guess is that the N2 fixators already ‘understand’ the parent cell’s mitosis signaling.

    The authors also say that the organelles have lost a number of genes for essential cellular functions, relying on the parent cell to provide those capabilities. By comparison, mitochondria have only 37 genes left, and chloroplasts weren’t known for having any DNA when I was at school, but are now known to have about 110 genes.

    In other words, a lot of evolution has already occurred and they are well on the way to being ‘proper’ organelles.