cross-posted from: https://lemmy.blahaj.zone/post/46294831

Gender identity among adolescents initiating hormone therapy is "highly stable," the authors write.

A few facts:

1. Yes, there is a male brain and a female brain. Examples:

-Men have 8-10% larger brains on average -Women have a higher percentage of grey matter -During emotional memory processing, men have greater activation in the right amygdala, while women have greater activation in the left amygdala -Women have greater cortical thickness -Men have a higher serotonin synthesis rate -Women have higher neuronal density in language-processing regions -Women have higher orbitalfrontal to amygdala ratio -During resting states, men show stronger functional connectivity within motor and sensory networks while women show stronger functional connectivity within social and emotional networks -INAH-3 is 2-3x larger in men than women -BNST is 50% larger in men

These are also there before puberty, it’s built in due to prenatal hormones

2. No, the fact the brain is a mosaic does not matter when discussing the fact that there is a male and female brain. People like to talk about the fact that individually these structures are really just group averages and the brain is a mosaic of masculinised and feminised structures, which is true, but when you look at the brain as a whole it really does cleanly fall into male and female brains. We know this because a stanford study trained an AI on resting-state fMRI scans of roughly 1,500 young adults, and it maintained over 90% accuracy in predicting sex across multiple independent datasets from different research centers. Now some may think that 10% inaccuracy means they're not their sex 10% of the time, which is absolutely not true, in reality it just shows the limits of AI and it could have been pushed further with different methods, more training data, less measurement noise, scanner effects etc.

3. These structures are definitely built by prenatal hormones. Not by x or y chromosomes (with some exceptions) or anything else. We know this because when looking at structural MRI, functional MRI and DTI of people with complete androgen insensitivity syndrome (CAIS), their brains are completely female typical in all the areas you’d expect. CAIS is a condition where the androgen receptor has a loss of function mutation and therefore cannot actually read the testosterone in the body, which makes the fetus develop along a female-typical pathway despite having xy chromosomes. The reason x and y chromosomes are talked about in sex is just because the y chromosome contains the SRY gene which starts the production of testosterone and turns the fetus into a male, that’s literally it. And the absence of that would make the fetus just develop along the female-typical pathway. But whichever pathway it develops on is entirely contingent on actual prenatal hormones and sensitivity to the hormones. Those with CAIS exhibit completely female-typical interests, social behaviour, sexual preferences, and a female identity. No, this stuff is not caused by socialisation, all the DSD and endocrinology literature strongly supports that socialisation actually does not play a major role in these sex differences and the vast majority of it is attributable to prenatal sex hormones. Of course this is just an N=1 but take david reimer for example, he was born male but was reassigned female with surgery at 22 months old following a botched circumcision, no one ever told him and everyone raised him as a girl named brenda, his hair was grown out, he was made to wear traditional female clothing, given hormone treatments at puberty etc, and he never knew he was born male until the age of 14 and he transitioned back to male. Long before he ever knew, he rejected his female identity, having male typical play preferences, saying he felt like a boy despite being told otherwise, was attracted to girls, etc.

4. No, unless you have an extremely rare genetic disease, prenatal hormones cannot be changed sufficiently enough to make a sex switch in the brain. There’s a pretty narrow range for variation within sex when it comes to prenatal hormones. Yes, some differences in testosterone or changes in timing of testosterone may change the brain slightly, but overall it’s still fairly sex-typical. The absolute difference in male vs female androgen signalling is massive, especially when talking about the crucial first trimester.

5. No, trans people actually do not sufficiently differ in their brain structure compared to their sex at birth, which is exactly what we would expect given all the other information. Sure, a few papers with a small sample size and ideologically driven funding may show small local changes compared to their assigned sex, but these papers are more focused on finding the differences between their assigned sex rather than looking at the big picture, which would be that the vast majority of them, if not all of them, would still have an overall brain that looks typical for their sex assigned at birth

As you can clearly see, in people without some rare genetic deformity, they simply would not have a sex inverted brain. Whether the validity of trans people is based on them having a sex-inverted brain is another discussion, but the actual claim that they have any major differences neurologically from their assigned sex itself is false.

cross-posted from: https://piefed.world/c/scientificarticles/p/1309821/workers-pesticide-exposure-linked-to-60-70-heightened-motor-neuron-disease-risk

In conclusion, the dark tetrad is mostly unrelated to political orientation.

(The dark tetrad being: psychopathy, narcissism, sadism, Machiavellianism)

I thought this was interesting because the previous theories made sense to me as explanations of political orientation for certain cohorts, and I'd like to understand what creates such attitudes.

NASA’s Curiosity rover has entered a Martian valley covered by an astonishing “sea” of tiny polygon-shaped fractures. The honeycomb patterns, each only a few inches wide, stretch across the landscape and even wrap around a nearby 20-foot-tall butte.

Understanding the narratives and learning from the valid critiques that draw people into feeling hesitant about vaccines offers a more nuanced way to understand these views—and may open the way for a more inclusive and respectful approach to healthcare.

cross-posted from: https://piefed.world/c/scientificarticles/p/1289720/accepting-free-will-doesnt-exist-could-make-us-less-hateful-and-ashamed

Sorry to bother you with this again. I have posted about this 2 times in the last 6 months already, because it is a fascinating topic and i want to talk about it. The issue is, whether there is renewable energy in the universe (truly renewable). Solar energy is called "renewable" but ultimately the sun will burn out. What then?

I have last time gotten the answers that "it's a stupid question because we have more urgent problems, such as corrupt politics etc.". Frankly, i disagree. This question is of existential importance, because it gives us an outlook into the far future. These perspectives are more valuable than playing 15 minutes of a computer game, which you could do instead of reading this article.

I uploaded a neat PDF here: https://files.catbox.moe/p8tg6i.pdf

Additionally i will copy-paste the article text here.

Spider Web Cosmology

From: https://feddit.org/u/gandalf_der_12te
Date: 2026-07-26
Subject: Renewable energy in a cosmological context

Abstract

In this paper i present a simple and clear approach to extract useful energy out of the cosmic expansion using mithril material wires, i.e. wires with very high Young's modulus and ultimate tensile strength. This energy is renewable, such that it represents a continuous and probably eternal power source.

Introduction and Motivation

The industrial revolution has allowed for a significant growth of humanity. While global population numbers were around 300 million around 1000 CE, it scaled to almost 8 billion by 2000 CE. That is an almost 30-fold increase. This was made possible largely by two inventions: the combustion-engine driven tractor and the natural-gas-based ammonia synthesis. Both consume massive amounts of energy, which mostly came from fossil fuels, which are not renewable. This naturally raises the question of whether humanity will ever run out of energy, which would induce a reversal of this massive growth, i.e. a significant population shrinkage. Related to this is the problem of climate change, i.e. whether there exists a long-lasting energy source that does not poison our own living conditions that we rely on.

Ever since solar energy started around 2020 to become economically competitive, many people have felt deep relief from the anxiety around climate change and the threat that humanity would eventually run out of fuel. However, the sun is predicted to burn out in approximately 10 billion years, and then humanity will have to find a new source of energy. While other stars do exist, those too will eventually run out of energy, with the slowest- burning stars (red dwarf stars) predicted to last for approximately 1000 billion years. Slower-burning stars do not practically exist as they would not be massive enough to ignite nuclear fusion in the first place.

What other sources of energy are there in cosmology? Especially, do sources exist that do not run out after a while, i.e. that are truly renewable?

Scope and Context

This paper uses the insights from general relativity, especially cosmic expansion, and simple mechanics to present a mechanism for renewable power in cosmology. While quantum aspects, such as vacuum energy, are highly interesting and might slightly change the reality, they’re left out of this analysis and regarded as an extra feature of nature that will have to be stacked on top of this one.

Mechanism

The term „spider web cosmology“ is justified if one visualizes the core concepts of this proposal:

An array of wires made from a very thin (lightweight) material called „Mithril“ are laid out throughout the universe, which have extremely high elasticity (Young's modulus), which means they exert force when stretched without significantly changing length.

Living organisms reside at the intersection points. As the intersection points are pulled away from each other over time, the wires between them will be stretched. The force that each wire exerts can then be calculated from Hooke’s law: F=σ⋅A=E⋅ε⋅A , with F being force, σ being stress, E being Young's modulus, ε being axial strain, A being cross-section area.

The mithril wires are chains of small link elements. As the living organisms at the intersection point let the wires contract from time to time, while generating power from that contraction, new link elements are produced and attached to the wire.

The mithril wires have to be produced from new matter that gets produced from a matter-anti-matter pair, that gets produced from the energy harvested from the chain relaxation. In other words, the chain has to release more energy when it relaxes than the rest mass of the mithril chain links.

This is why this mithril material has to be extremely lightweight while still having high Young’s modulus and high ultimate tensile strength. Practically speaking, I’m not entirely sure whether such a material could exist. Using simplifications and a linear model of elasticity, common steel does not have good enough properties for this application.

I will proof this in the following calculation. For this, we have to look at the rest mass of a steel chain link and the energy that can be released when the chain is relaxed by the length of one link element. Let x be the length of one link element.

The work W1 released by the chain is W 1=F⋅x=E⋅ε⋅A⋅x , while the rest mass (rest energy W2) of one chain link is W 2= ρ⋅A⋅x with density ρ, therefore for W1 to be larger than W2 one gets the relation E⋅ε > ρ. Comparing this to the actual values for steel:

• E is around 200 GPa (2·10¹¹ J/m³)
• ρ is around 8 000 kg/m³, equivalent to a rest energy of around 8·10²⁰ J/m³

Therefore, ε would have to be larger than 4·10⁹, i.e. the steel wire would have to stretch to 4 billion times its usual length. However, commercially available steel used in construction typically breaks apart for ε > 3·10⁻³ (Source: Wikipedia). These steel wires would have to have a factor 10¹² higher ultimate tensile strength!!

The judgement is still out on whether a good enough mithril material could hypothetically exist.

Pioneering study linking noise pollution to Parkinson’s finds 3% increase in risk for every 11.5dB rise in noise levels

Existing research has found potential biological pathways that link noise exposure to Parkinson’s disease, largely due to stress responses and disrupted sleep.

The study, published in Jama Neurology, included 3.1 million Danish participants aged 40 and over, and followed them for 18 years.

This is an exclusive report from Science News', jointly organized with Retraction Watch, on a gene editing tragedy.

The tragedy involved two parents paying $860,000 to partially fund an unapproved clinical trial of 1 to save their daughter from a rare neurodevelopmental disease, the work being done by a superstar researcher in China working at a highly prestigious research hospital, the girl subsequently dying because the research behind the trial was shoddy, and the death of the girl being buried. The research behind this was subsequently published in Nature, but the human trial component was completely erased.

This might shape up to be one of the largest gene editing scandals for a while

Try this Wayback Machine link if you are paywalled

There's also a brief follow-up article by Science News

This rule also applies to photons reflecting from mirrors. The photon is reflecting from the mirror, and the electromagnetic field is varying regularly and smoothly changing from the incoming to the reflected wave. The transmitted wave doesn’t exist, so the amplitude is a happy zero.

Then the mirror is yanked away. The reflected wave’s amplitude abruptly drops to zero, and the transmitted wave suddenly jumps from zero. Those are two sharp transitions that require a lot more bandwidth than the original photon had. Our photon that has been cut off is still in a superposition of reflected and transmitted. But it also has a sharp edge, which requires a multitude of photons at different frequencies.

Cutting a photon in half generates a rainbow. And as far as I can tell, the generated photons are in a superposition of both reflected and transmitted light. But since there are potentially many photons, both transmitted and reflected light could be measured simultaneously.

For the first time, scientists have found a rocky planet with an atmosphere orbiting in a star’s habitable zone. Researchers from Harvard University say the Earth-like world has conditions similar to those on Earth.

The exoplanet, LHS 1140 b, is 48 light-years from Earth. It orbits a red dwarf star at a distance close enough for water to remain liquid, but far enough away that it would not boil.

and the paper https://www.science.org/doi/10.1126/science.adu4373