1
 
 

One of my favorite programming books.

Filled with gems like this:

Numbers that fool the Fermat test are called Carmichael numbers, and little is known about them other than that they are extremely rare. There are 255 Carmichael numbers below 100,000,000. the smallest few are 561, 1105, 1729, 2465, 2821, and 6601. In testing primality of very large numbers chosen at random, the chance of stumbling upon a value that fools the Fermat test is less than the chance that cosmic radiation will cause the computer to make an error in carrying out a “correct” algorithm. Considering an algorithm to be inadequate for the first reason but not for the second illustrates the difference between mathematics and engineering.

Full Text - https://web.mit.edu/6.001/6.037/sicp.pdf

2
 
 

Star Trek and Star Wars are both dying. Star Trek turns 60 in 2026 with nothing in production. Star Wars just posted its lowest box office opening ever. So. Who killed Star Trek Wars? HINT: it's not JJ Abrams, "woke" or Rey!

generated summary

Origins: Star Trek, Star Wars, and U.S. power

  • The USS Enterprise CVN-65, the first nuclear-powered aircraft carrier, inspired the USS Enterprise NCC-1701; Roddenberry originally called his starship Yorktown, and Star Trek's naval structure became an idealized image of the U.S. Navy.
  • NBC rejected the first pilot as too cerebral but commissioned Star Trek because its command structure felt relatable to the U.S. Navy; the earlier video "Star Trek is propaganda" supplies the full case for reading the Federation as an idealized U.S. naval superpower. [1]
  • Vietnam shattered that ideal. George Lucas directly tied Star Wars to Vietnam and the Viet Cong: the advanced technological empire loses to low-tech rebels, while Enterprise launching combat sorties is the real-world counterpart to a Star Destroyer projecting force without permission. [2]

The American mythos

  • Every era has a mythos: stories such as the Olympians, the Ramayana, and Romulus and Remus tell a civilization where it comes from and shape what it becomes.
  • The U.S. has spent its short history manufacturing such stories through the Old West, the Founding Fathers, advertising, schools, and mass culture.
  • Francis Bellamy's 1892 Pledge of Allegiance grew out of a campaign to sell flags to schools; its original straight-arm salute was replaced by the hand-over-heart practice in 1942.
  • Hollywood's capitalist competition produced the conjoined mythos of "Star Trek Wars," built around postwar America's central question: how should a superpower use its power?
  • Star Trek is America's highest self-image: liberal democratic power making alliances, rebuilding enemies into friends, and using science and technology to raise up the wider world without domination.
  • Star Wars is the dark image of the same power: America as an empire with superweapons, vassals, coercion, and overwhelming force.
  • Together they form an American culture divided over whether America is the Federation or the Empire.

Why the mythos died

  • By 2026, with Star Trek at 60 and Star Wars approaching 50, "Star Trek Wars" is a dead mythos because the American power it was built to interpret is itself dying.
  • Feral Historian's 60th-anniversary reflection prompted this essay; despite coming from opposing political directions, both channels now sit outside the liberal center and critique the same exhausted myths.
  • The dissident right and radical left are gaining traction for the same reason: the liberal-center myths no longer correspond to the material order they were built around.
  • The Next Generation and Deep Space Nine embodied the institutional confidence of Pax Americana, while the Star Wars prequels explored a decadent republic rotting into dictatorship through emergency powers in the War on Terror and Patriot Act era.
  • The death began in the 2000s, but J.J. Abrams did not personally kill it, and neither did "woke": Star Trek and Star Wars were always diverse, political, and full of empowered women.
  • Corporate capitalism is the more attractive culprit: Disney bought Star Wars as exploitable franchise property, while Star Trek passed through Viacom and then into the Paramount-Skydance empire controlled by David Ellison and backed by Larry Ellison.
  • That ownership now places Star Trek under billionaires who will not permit the franchise to attack certain U.S.-supported political travesties with the freedom it once used to attack Vietnam or Afghanistan.
  • Andor does not save Star Wars; it shows why Disney's factory model is failing. The earlier "Andor : a Marxist story" identified the politics, and Tony Gilroy demonstrates that art is made by artists without corporate content systems. [3]
  • Capitalism alone cannot be the killer because both franchises were born from corporate profit-seeking in the first place.

The collapse of U.S. power

  • America itself is the killer: "Star Trek Wars" was America working through what to do with overwhelming power, and it was not equipped to handle the collapse of that power.
  • The military symptoms are aircraft carriers becoming obsolete and Patriot interceptors costing roughly 200 times the drones they destroy; the deeper reality is that America is about 4% of world population and 15% of global GDP, with that share falling.
  • America is neither Federation nor Empire. Its power was never destined; it was contingent on geography, historical fortune, and ruthless choices, and those contingencies are fading.
  • Faced with decline, America has chosen the darker myth and is making a last attempt to become the evil empire: MAGA embraces imperial aesthetics, domestic stormtroopers, and the possibility of catastrophic nuclear escalation.

The choice that remains

  • All national myths are lies and propaganda to some degree, but they are also visions that orient decisions toward futures that do not yet exist.
  • The Empire leads only to the dark side; the Federation's strength was never its starships but the Prime Directive, restraint from imposing itself by force, and cooperation.
  • The Federation was always America's best destiny: not a guaranteed destiny, but one that can still be chosen and built.

References

  1. [00:59] Star Trek is propaganda — :contentReference[oaicite:0]{index=0}
  2. [01:45] George Lucas Reveals How Star Wars Was Influenced By the Vietnam War — :contentReference[oaicite:1]{index=1}
  3. [11:38] Andor : a Marxist story — :contentReference[oaicite:2]{index=2}

3
 
 

I bought a switched PDU from aliexpress, and i broke the rule of buying from ali... I tested it! The Live and Neutral wires on the PDU are crossed over.

I've attempted to return it, but aliexpress keeps denying me saying its a grounding problem with my test setup... hence why i stuck the fluke in directly for a direct illustration.

4
 
 

USCSB drops another banger on after action analysis and engineering failure modes!

A CSB safety video on its investigation into the deadly January 28, 2021, liquid nitrogen release at the Foundation Food Group (FFG) poult

5
 
 

motivationI got some new sfp modules today, and i wanted to validate them... I was feeling lazy to drag two machines together to plug in the sfp modules for a point to point link (plus many machines don't even have sfp slots), I was feeling lazy to daisy chain two switches together to use the sfp modules.....

I do have iperf3 testing already setup on a stable host server pair in my network... so

Setup two vlans A, B. These vlans have no dhcp, no routes, nothing - Attach a interface to each vlan, assign as static ip address on the same subnet, run iperf3 in server mode. The test comes from how you bridge the vlans: A switch with vlan A on port A, and vlan B on port B, now if you plug in SFP.A and SFP.B and bridge with a cable... iperf3 can connect.

This extends your in place network path from interface A to interface B by forcing it to go over SW.PortA->SFP.A->Test Cable->SFP.B->->SW.PortB

Host interface A
  │
  │ VLAN A
  ▼
switch.portA ── Test SFP.A
            │
            │ test-cable
            │
switch.portB ── Test SFP.B
  ▲
  │ VLAN B
  │
Host interface B

Run iperf3 in a loop, and now you can swap modules/cables and get the full benefit of a point to point cable test without having to move any machines around. This will even work with a single machine for testing, with a interface on A and B (different namespaces), you just have to double your iperf results mentally.

I realize this is fairly niche, and probably obvious to many people, but I just stumbled upon it today and thought it was pretty neat.

FWIW my SFP modules ran at 9.6gbps, so I'm happy with them!

6
 
 

but he did manage to make a realistic face eventually

7
 
 

i just found out that firefox finally made profiles easy to use - a first class feature like chrome.

I found out from this techlore video https://youtu.be/dwFSytu_JUw

and even better then chrome, in macos dock bar, each active profile has its own icon

Chrome has had profiles for a long long time, easy to segment accounts/jobs for better isolation (extensions, etc).

Firefox has always had profiles hidden, they were just a super pain in the butt to the point where it wasn't really usable.

Better isolation is great!

8
 
 

This is a fun way to kill a few days learning nixos and setting up a home media stack.

I have done a tremendous amount of bikeshedding playing with this project. great fun

Finally justifying my home network over-building - all I had to do was try to move around 100gib objects constantly!

this module wraps a VPN namespace around (Seerr, Prowlarr, Sonarr/Radarr, (torrent/nzb), jellyfin), it's pretty declarative, there are some things that still manually need to be setup by hand (not the fault of nixos).

For extra complexity - My nixos is a thin os backed by NFS over 10g fibre, on a isolated vlan that can only egress the network to known wireguard ports.

I spent so much time trying to optimize bandwidth I ran out of things to download!

9
 
 

Wilhelm Röntgen's accidental discovery of X-rays in 1895 revolutionized science and medicine. While repeating an experiment on cathode rays, he observed a mysterious fluorescence emanating from his equipment, far beyond the reach of the known rays. This led him to investigate a new, penetrating form of radiation, which he termed X-rays. His initial experiments revealed their ability to pass through solid objects, famously producing the first radiograph of his wife's hand. The medical community quickly recognized the diagnostic power of X-rays, leading to their widespread adoption in surgery and treatment. Further research by scientists like Laue and the Braggs established X-rays as electromagnetic waves with wavelengths shorter than ultraviolet light, and their diffraction by crystals opened up the field of X-ray crystallography, providing insights into atomic structure and the composition of matter. Today, X-rays are a crucial tool in non-destructive testing, industrial quality control, and advanced medical imaging.

10
 
 

The mechanisms underlying impaired temperature regulation in older age, and the ability of older adults to physiologically adapt to heat exposure remain understudied. This study determined the effects of older age on the neural control of body temperature during heat stress and its plasticity in response to passive heat acclimation. The neural control of body temperature during heat stress was quantified with measurements of skin sympathetic nerve activity (SSNA), local sweat rate (LSR) and cutaneous vascular conductance (CVC) performed on older (n = 15, 60–78 years) and younger (n = 16, 21–40 years) adults before and after seven consecutive days of hot water immersion. Pre-acclimation, the onset threshold of SSNA (mean difference [95% CI]: −0.12°C [−0.38, 0.15], P = 0.518), LSR (−0.14°C [−0.37, 0.08], P = 0.265) and CVC (−0.09°C [−0.33, 0.14], P = 0.600) did not differ between older and younger adults. Heat acclimation reduced resting core temperature and increased sweating in both groups. Post-acclimation, the onset threshold of SSNA (−0.19°C [−0.36, −0.02], P = 0.024), LSR (−0.15°C [−0.29, 0.00], P = 0.036), and CVC (−0.23°C [−0.41, −0.06], P = 0.009) was reduced in older adults and these reductions did not differ from those observed in younger adults (P ≥ 0.703). These results show that older age does not alter the neural control of body temperature during heat stress, nor its plasticity to heat acclimation. The implications of these results are that passive heat acclimation may be a practical strategy to improve the physiological resilience of older adults to extreme heat events.

Full Paper - https://doi.org/10.1113/JP290417

11
 
 

When you combine a bouncy surface with a bouncy ball, you might kill the bounce! You have to tune their vibrations!

12
 
 

Ben turns over a new leaf in Arc Raiders to finally join friendlier servers.

13
 
 

Most men think erectile dysfunction is a bedroom problem. It's actually one of the earliest warning signs of cardiovascular disease, capable of showing up three to five years before a heart attack.

In this episode, Dr. Gabrielle Lyon sits down with Dr. Amy Pearlman, a urologist trained in men's sexual health, to discuss:

  • Why ED is a symptom of vascular health, not a standalone disease and how the artery feeding the heart is roughly double the size of the one feeding the penis, so problems show up "down there" first
  • Why "normal" testosterone can be meaningless, and the questions to ask before accepting a lab result that didn't flag
  • How daily erections preserve penile tissue the way water keeps a sponge supple and why disuse can cost noticeable size over just a few months
  • That cardiovascular exercise can rival ED medication for improving erectile function, making your heart health the real fix
  • How to track erectile fitness before there's a problem, instead of waiting until something breaks

By the end, you'll understand the single signal your body uses to flag heart and metabolic risk early and the simple, mostly drug-free steps that protect both your cardiovascular health and your sexual function for life.

summerizerErectile function is cardiovascular data

  • Erectile dysfunction is a vascular-system symptom, not a standalone disease.
  • The penis can reveal cardiovascular dysfunction before the heart because penile arteries are smaller.
  • A man can have erectile dysfunction years before a heart attack, stroke, or other cardiovascular event.
  • The erection is a practical health signal because men often seek care for sex before metabolism.
  • Sexual function gives clinicians a direct path into blood pressure, insulin resistance, obesity, sleep, drugs, alcohol, and exercise.
  • Cardiovascular exercise can improve erectile function enough to land more strongly than abstract heart-health advice.
  • Young men need to learn that erections are tissue-health events, not only performance events.
  • Daily blood flow keeps erectile tissue oxygenated, elastic, and usable.

The men's-health education gap

  • Men can fall out of medical care after pediatrics because adult medicine gives them few clear entry points.
  • College-aged men may go decades without care when early adult health visits feel irrelevant, embarrassing, or dismissive.
  • Medical training includes required women's-health exposure, yet male-specific sexual and reproductive health often receives little structure.
  • Many male patients know very little about erections, ejaculation, fertility, penis anatomy, testosterone, or prostate symptoms.
  • Young men ask legitimate questions that health systems often fail to answer plainly.
  • Better men's-health education starts with normal anatomy and function, not fear or pathology.
  • Men need a health conversation that feels practical, private, and useful before crisis.

The five S's for men's health

  • Young men's questions fit into sex, streams, steroids, sperm, and size.
  • Sex includes erections, libido, orgasm, ejaculation, porn, relationship concerns, and practical sexual function.
  • Streams includes urinary flow, prostate concerns, testicular concerns, and the basic mechanics of peeing.
  • Steroids includes testosterone, anabolic agents, gym culture, online clinics, fertility suppression, and monitoring.
  • Sperm includes semen analysis, sperm banking, fertility goals, and how lifestyle changes may show up months later.
  • Size includes normal ranges, anxiety, restoration after loss, safe devices, and enhancement requests.
  • This structure gives men permission to ask the questions they already have.

Clinical intake and lifestyle triage

  • Clinical intake starts where the patient is comfortable and then widens the conversation.
  • Erection quality opens a pathway into cardiovascular fitness, metabolic health, sleep, medication use, and substance use.
  • Obesity, insulin resistance, poor sleep, vaping, cocaine, marijuana, and alcohol can all matter for erections and hormones.
  • Patient willingness should guide change before a long list shuts him down.
  • A man may need cardiology, primary care, sleep medicine, fertility care, mental-health care, or sexual-medicine care.
  • Good triage does not overwhelm the patient with every possible referral at once.
  • The goal is keeping the man engaged in care long enough to improve the underlying system.

Testosterone, steroids, and harm reduction

  • Testosterone belongs in the workup for men with sexual-function concerns.
  • A lab range is not enough; a 25-year-old with testosterone around 300 can be symptomatic even when the number is marked normal.
  • Safety comes first: possible harm must be known, and monitoring must prevent harm.
  • Testosterone therapy can suppress sperm production, so fertility goals must be handled before starting.
  • Testosterone is not reliable contraception, but it can dramatically reduce spermatogenesis in some men.
  • Baseline semen analysis matters when a man wants children later or is unsure about future fertility.
  • Monitoring includes symptoms, testosterone level timing, hematocrit, lipids, estrogen, and side effects.
  • AUA guidance is helpful, but real-world dosing requires knowledge of formulations, timing, peaks, troughs, and patient response.
  • Testosterone injections, topicals, pellets, oral formulations, peptides, and anabolic agents are not interchangeable.
  • A high testosterone number alone does not answer the clinical question; symptoms and safety markers matter.
  • Young men using or thinking about anabolic agents need harm-reduction care, not expulsion from the clinic.
  • Baseline hormones, estrogen, hematocrit, and sperm data help men make safer decisions.
  • Clinicians should learn from guidance, experienced specialists, and patient experience when formal training is thin.

Fertility and semen testing

  • Men who may want children should know their semen status before starting hormones or other fertility-risking interventions.
  • Semen analysis is the only way to know whether sperm exist, how many there are, and how they move.
  • At-home semen testing can lower the barrier for young men who are curious or hesitant.
  • A clinic-based semen analysis is still needed when fertility is active, results are abnormal, or sperm freezing is being weighed.
  • Sperm development takes about three months, so lifestyle or medication changes need time before the next measurement.
  • Marijuana, alcohol, sleep, diet, exercise, and hormones can be tested through repeated semen and hormone measures.
  • The point is not moral judgment; the point is measurable cause and effect in one man's body.

Erectile-dysfunction testing and Peyronie's disease

  • Penile Doppler ultrasound uses a strong injection to test blood inflow and outflow.
  • A test only helps when it matches the real-world problem the patient is having.
  • When Cialis or Trimix produces a strong erection, that result can be more useful than an artificial test that fails to recreate the complaint.
  • Ultrasound is especially useful when a man has Peyronie's disease, scar tissue, a lump, curvature, shortening, or deformity.
  • Peyronie's disease is not just curvature; pain, indentation, narrowing, buckling, intercourse difficulty, and distress can all matter.
  • Congenital curvature can be normal when it is stable and not interfering with sex.
  • Men should know that penile trauma during sex can contribute to Peyronie's disease.
  • Safer sex mechanics and full rigidity reduce the risk of bending injury.

Blood-flow tools and medication

  • The penis can be handled like any body part: structure, blood flow, function, maintenance, and restoration.
  • Tadalafil can support blood-flow signaling by preserving nitric-oxide effects through PDE5 inhibition.
  • Daily Cialis can be useful beyond on-demand erections when the goal is genital blood-flow support.
  • Nitric-oxide supplements may help some men, but tadalafil is often the direct tool when blood flow is the target.
  • Medication decisions still depend on the person, side effects, contraindications, and clinical context.
  • Men do not need to wait for severe decline before learning how to preserve function.
  • Stronger erections can make sex safer by reducing partial-rigidity bending and trauma.

Daily erections and erectile fitness

  • Research on normal male physiology points to multiple nocturnal erections per night.
  • Many men never learn that nighttime erections are a normal sign of erectile tissue health.
  • When daily or nightly erections disappear, tissue can lose length, girth, elasticity, and responsiveness over time.
  • A wearable erection tracker can separate libido from erectile mechanics.
  • Firmness, duration, and number of erections can be tracked like other fitness measures.
  • Tracking can show how alcohol, marijuana, sleep, exercise, stress, and medication affect erectile function.
  • This data can motivate behavior change because it is personal and immediate.
  • Venous leak means blood enters the penis but does not stay there well enough for a durable erection.
  • An erection ring can function like a compression stocking by helping trap blood in the erectile chambers.
  • Rings are simple, inexpensive, and available without a prescription, but they must be used safely.

Vacuum pumps and restoration

  • Vacuum erection devices are underused for penile restoration and maintenance.
  • A pump can pull blood into erectile tissue, stretch the tissue, and remind a man that engorgement is still possible.
  • The goal is light pressure, good lubrication, a good seal, and patience, not aggressive overpumping.
  • Pubic hair may need trimming so the cylinder seals against the body.
  • Men should use water-based lubricant on the base, the cylinder, and the penis.
  • The technique is a few pumps, relaxation, more gentle pumping, and attention to comfort.
  • Pulling a testicle into the cylinder is a sign that the seal or setup needs adjustment.
  • After erection loss or size loss, a daily pump program for about three months can be reasonable restoration work.
  • A pump is not proven to enlarge an already healthy normal penis for enhancement.
  • Urology has more data for restoring loss than for enlarging normal anatomy.

Size, normal ranges, and enhancement requests

  • The largest pooled measurement data show average erect length and girth are far below what many men think is normal.
  • Most men are not six inches erect, and average erect girth is around four and a half inches.
  • A size conversation should reduce shame when reassurance is enough.
  • Some men seeking enhancement are not broken, dysmorphic, or sexually dysfunctional.
  • They may already have good sex and still want to know what is possible.
  • Saying there is no help can push men toward unsafe pills, oils, injections, or online procedures.
  • Enhancement should be handled from abundance when appropriate, not only from deficiency.

Traction therapy and RestoreX

  • Penile traction is most established for Peyronie's disease and length restoration.
  • RestoreX clamps the flaccid penis and stretches it in a controlled way.
  • The device was developed so men could get benefit with far less daily time than older traction devices.
  • Peyronie's scar tissue does not stretch like normal tissue, so traction can help remodel curve and length.
  • RestoreX can stretch and counter-bend the penis, which matters when curvature is the target.
  • Traction can be used alone or with Xiaflex collagenase injections in selected Peyronie's patients.
  • Combination care can produce better outcomes than either traction or injection alone.
  • For motivated men with length loss, a practical program may use RestoreX about thirty minutes daily for several months.
  • Evidence is stronger for restoring lost length than for adding length to a healthy penis.
  • Penile lengthening surgery by cutting the suspensory ligament can create stability problems and is not the preferred path.

Girth enhancement and functional goals

  • Hyaluronic-acid filler can be injected between the erectile chambers and penile skin to increase girth.
  • There is no FDA-approved injectable product specifically for penile girth enhancement.
  • Hyaluronic acid is attractive because it can be dissolved with hyaluronidase if needed.
  • A half-inch to one-inch girth increase is a common realistic goal, and some men want more.
  • The glans does not enlarge with shaft filler, so aesthetics require attention to the transition from head to shaft.
  • Girth can matter functionally when sensation or partner sensation is the issue.
  • Aging, erectile dysfunction, tissue loss, and childbirth can change how bodies fit together during sex.
  • Enhancement work should include sexual function, safety, aesthetics, expectations, and reversibility.

Female erectile tissue and sexual tools

  • Women have extensive erectile tissue, but much of it is internal and hidden behind the labia.
  • The clitoris is larger than the visible tip and has a wishbone-like internal structure.
  • Many women need clitoral stimulation for orgasm and do not climax from penetration alone.
  • Sex with an unengorged clitoris is comparable to sex with a flaccid penis.
  • Full-area stimulation can matter more than precise stimulation of only the visible tip.
  • Wand vibrators can cover the broader clitoral region better than tiny bullets for some women.
  • Suction or pressure-wave devices work differently from vibration and may reduce the problem of temporary desensitization.
  • Toys are not a sign of failure; they are tools for pleasure, training, and better partnered sex.
  • When a person wants orgasm with and without a toy, practice should include both pathways.
  • The best sex uses the available tools and does not protect a fragile idea of what sex is supposed to be.

Closing principle

  • Penis health is health: blood flow, hormones, nerves, tissue, fertility, psychology, relationships, and education all connect.
  • Men should receive clear information early, before erectile loss, fertility panic, unsafe enhancement, or avoidable cardiovascular risk.
  • Sexual health care works best when it replaces shame with normal anatomy, measurable data, and practical tools.

References

14
Book haul to read (hackertalks.com)
submitted 5 months ago by to c/interesting@hackertalks.com
 
 

I'm a bit of a book addict, I am currently reading 3 books right now but might pause one for book 2 of dungeon crawler carl

15
 
 

Yes, its generative, but it illustrates the idea

I was going to post on !fedimemes@feddit.uk but that instance has a no generative content policy.

I think a major limiter on lemmy growth are the instances that encourage talk of violence, crime, being abusive to others, and are just generally super combative...bad neighbors - maybe not written into the instance rules, but as demonstrated by what instance admins don't enforce on their own users.

I know a schism is scary for a small society like lemmy, but I'm starting to think its necessary

if not a defederation, some protocol level whitelisting of users or comms that demonstrate the bare minimum of being able to play nicely with others (realizing this would take some novel work - like adding a user level whitelist to federation rather then the current banlist, and while were at it some eventual consistency in meta-state in bans)

Basically, the toxicity needs to be partitioned off, gated, or some level of meta-moderation for instances that wont police themselves to minimum levels of behavior. It's embarrassing to share lemmy with people I know now, given how off the wall it quickly gets.

16
 
 

Photos of a week's worth of food for a family from selections around the globe. Very interesting.

https://www.menzelphoto.com/gallery/Hungry-Planet-Family-Food-Portraits/G0000zmgWvU6SiKM/C0000k7JgEHhEq0w

17
 
 

Just fun to browse whats going on globally.

18
 
 

It's nice to see a maker get into the zone.

The failures, relentless cursing, but overcoming it is what makes this feel so real.

19
 
 

Although the vast majority of patients in forensic psychiatry are treated using pharmacological agents, clinical and ethical concerns about their use have led to the consideration of alternative strategies to reduce aggression that is common in forensic psychiatric settings. One non-invasive and benign biologically-based treatment approach involves nutrition. This article provides a mini-review of the recent evidence on four salient nutritional factors associated with aggressive behavior, namely omega-3 fatty acids, vitamin D, magnesium, and zinc. The current evidence base indicates that lower omega-3 levels are associated with increased aggression. Although research on vitamin D and zinc in relation to aggressive behavior is more limited, there is initial evidence that they are negatively associated with aggression in healthy participants and in psychiatric samples. The relationship between magnesium and aggression varies depending on how magnesium is assessed. Findings from experimental trials reveal that nutritional intervention in the form of omega-3 supplementation has the potential to serve as an effective mode of treatment, with effects that can last beyond the intervention period. There is also support for the utility of nutrition to improve our understanding of how social processes are linked to aggression. In light of the nascent, but promising findings on the role of nutritional factors on aggressive behavior, directions for future research are discussed.

https://doi.org/10.3389/fpsyt.2023.1176061

20
More Power! (hackertalks.com)
submitted 6 months ago by to c/interesting@hackertalks.com
 
 
21
 
 

I have a few extra days in Tokyo after a business trip, what fun geeky things can you recommend?

22
 
 

Lecture presentation at deep river library on new book acquisition April 17, 2026

summerizerPurpose and learning stance

  • A 16-chapter, 640-page book on nuclear reactor core materials is the basis of this mostly non-technical talk.
  • The book comes from enough years in the field to connect ideas that were not obvious earlier.
  • Writing the book forced a return to old physics lessons and later understanding of what earlier lecturers had meant.
  • The book is for a younger engineer and for young engineers and scientists of ordinary ability who are willing to learn.
  • Learning begins with accepting that there is still something to learn. Confidence, humility, and engineering culture
  • Dunning-Kruger is a competence-confidence pattern tied here to much older observations by Machiavelli and Schopenhauer.
  • More learning brings a clearer view of the limits of knowledge.
  • The PhD viva left Malcolm feeling tiny, and his supervisor saw that feeling as proof that the process had done its job.
  • Research and management kept dividing people into two groups: receptive people who listened and unreceptive people who stayed willfully ignorant.
  • A little knowledge around reactor materials is dangerous because people can mistake shallow familiarity for understanding.
  • At Chalk River a supposedly surprising pressure-tube result fit the sample location, yet others reached the same answer only two years later.
  • At Queen's a DFT paper had omitted earlier work that cut against both the data interpretation and the theoretical assumptions.
  • Receptive people also stood out: a summer student and an Idaho project officer absorbed in hours what formal settings had not taught in much longer spans.

Atomic structure and deformation

  • Metal atoms behave like hard spheres whose bonding and packing drive crystal structure.
  • Close packing gives two main structures for common reactor metals: ABA stacking for hexagonal close-packed crystals and ABC stacking for face-centered cubic crystals.
  • FCC and HCP cover many reactor-core materials, but they are only two of the 14 crystallographic arrangements.
  • Crystal structure mattered enough to supply a joke about Bristol buildings looking orthorhombic rather than monolithic.
  • Plastic deformation in crystals proceeds through slip, twinning, and martensitic change, and engineering alloys add grain boundaries to that picture.
  • Grain boundaries are stronger than the grains because the regular atomic arrangement inside grains makes deformation easier there.
  • Dislocations are line defects where bonds have been broken locally, and they let metals deform by sequential bond breaking and reforming instead of one huge shear event.
  • A caterpillar ripple, moving a carpet, and tearing a telephone book a few pages at a time capture how dislocations lower the needed force.

Radiation damage and microscopy

  • Neutron bombardment creates point defects when enough energy is transferred to knock atoms out of lattice sites.
  • A fast neutron can launch a displacement cascade, and even thermal neutrons can create a few displacements through recoil from emitted gamma radiation.
  • Nickel is especially important because nickel-58 can transmute to nickel-59, and nickel-59 then drives extra damage while producing hydrogen and helium.
  • The displaced atoms and the vacancies they leave behind can migrate, cluster, and change microstructure and material properties.
  • Transmission electron microscopy lets these defects and diffraction effects be seen directly, including vacancy loops and interstitial loops.
  • High-voltage microscopy allows thicker samples and in-situ irradiation, so defect motion can be watched while damage is being created.
  • In Stuttgart a vacancy loop grew during irradiation at 300 C, which showed that vacancies were mobile under those conditions.
  • Radiation can also drive phase change, including an amorphous transformation in a zirconium precipitate first seen at Chalk River by Ross Gilbert.
  • A zoom from that precipitate out to the M13 globular cluster made the point that structure can look surprisingly similar across radically different length scales.

Practical reactor materials and components

  • Calandria tubes and pressure tubes have distinct microstructures, and pressure tubes matter because they are the pressure boundary inside the core.
  • Cold-worked pressure tubes contain an enormous dislocation density, enough that a cubic centimetre would stretch from Earth to the Moon and a full tube would reach Pluto and back twice if the lines were joined end to end.
  • Heavy-water CANDU reactors run on natural uranium, use heavy water for coolant and moderator service, and rely heavily on zirconium alloys because zirconium absorbs few neutrons.
  • Some internal parts still need nickel alloys, and the garter spring is a critical nickel-alloy spacer that keeps the hot pressure tube away from the colder calandria tube.
  • Contact between those tubes creates a cold spot, blister formation, and possible tube failure, which is why earlier failures in 1983 and 1986 mattered so much. Spacer failures, helium, and irreversibility
  • A spacer removed after about 15 years in service arrived broken into many pieces, and truck transport did not cause that damage.
  • Transit simulation showed that an unirradiated spacer could be deformed but was hard to break, while gentle cyclic bending could break it by fatigue like a paper clip.
  • The irradiated spacer fractured differently, with faceted grain-boundary fracture rather than the fatigue surface of unirradiated material.
  • Malcolm recognized that brittle intergranular behavior as helium embrittlement and had a hard time convincing others that CANDU conditions generate that much helium.
  • The helium level was put at roughly a hundredfold above comparable U.S. reactor conditions for this kind of material.
  • In a heavily damaged sample without helium, grain boundaries stayed comparatively clean even after about 500 displacements per atom.
  • With helium in the material, vacancies were stabilized at grain boundaries and perforated the boundary instead of being absorbed.
  • Annealing does not solve that problem because helium stays in the material.
  • Helium is forever.

References

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Ever wonder why Task Manager shows a CPU value that doesn't "feel" right? Dave explains why Task Manager shows you the values it does and how they are determined.

summerizerWhat the CPU percentage is

  • Task Manager does not read a single instantaneous "CPU busy" value from Windows.
  • The percentage is a periodic summary of activity that happened between refreshes.
  • The display timer controls when the UI updates, but it does not supply the CPU denominator.
  • CPU usage is an accounting result built from choices about cores, modes, idle time, interrupts, DPCs, and averaging windows.

How the percentage is computed

  • Task Manager asks the kernel for cumulative per-process execution time, split across user time and kernel time.
  • Each process behaves like an odometer: the code reads the running total, subtracts the last sample, and gets that process's CPU delta for the interval.
  • The code also does a full pass across the process table, sums all current cumulative times, subtracts the previously remembered total, and gets the system-wide total delta.
  • The per-process CPU percentage is that process delta divided by the total delta across all processes during the same sample window.
  • This keeps the result meaningful even when the UI timer fires late or unevenly.
  • The old code uses integer arithmetic and rounding to produce a fast, stable percentage without floating-point work in a hot UI path.

Why the number can feel wrong on modern hardware

  • The meter answers how long a process was scheduled, not how many cycles or how much work the hardware delivered during that time.
  • Dynamic frequency scaling, turbo behavior, thermal limits, deep sleep modes, and parked cores break the old assumption that a second of scheduled CPU time maps cleanly to a fixed amount of work.
  • A process can show about 50% CPU for half of a sample window even though the actual work done in that half-window can vary widely with clock speed.
  • The percentage is closer to occupancy than productivity.

Why totals, cores, and idle time confuse people

  • On a multicore system, the process column answers what share of total machine CPU capacity a process consumed during the sample window.
  • One process fully saturating one core on an 8-core machine lands near 12% to 13% of total machine capacity, not 100%.
  • The System Idle Process is the bucket for unclaimed cycles, so busy time plus idle time adds up to the full machine total for the interval.
  • The number is an average over the recent refresh window, so a short burst can be diluted into a small value or rounded to zero.
  • Watching total CPU can hide a single saturated core, especially on machines with many cores or threads.

Why the code contains clamps, assertions, and edge cases

  • The code clamps computed CPU above 99 back to 99 because early builds sometimes produced totals above 100% from a rare kernel-side accounting anomaly.
  • The bug was trapped with assertions and eventually confirmed and fixed on the kernel side.
  • The code invalidates old process records when cumulative CPU time moves backward, because PID reuse can make one dead process and one new process share the same identifier across samples.
  • The code also marks an idle-process time of exactly zero as bogus and invalidates it.
  • WOW tasks add another accounting wrinkle: child 16-bit task times are capped so they do not exceed the parent NTVDM total.

What the tool is for

  • CPU usage is a ratio assembled from accounting decisions, not a substance that exists on its own.
  • Task Manager favors a cheap, robust, human-readable approximation over a more forensic display.
  • A 0% reading can still mean less than 1% average activity in the sample window, and a bouncing 0%, 6%, or 12% can match a bursty worker thread behaving normally.
  • Catching microstutters, scheduler hiccups, or DPC storms needs a more specialized view than a one-second UI average.
  • The old Windows NT4 Task Manager still runs on Windows 11, groups CPUs in sets of 16, and shows how much of the original design still survives.
  • The final number is a fast, useful summary of a complicated reality, as long as it is read as an accounting ledger instead of a thermometer.

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Learn the types of naval mines which Iran has, and why some are harder to sweep than others. Unscripted and unedited, just a real person sharing knowledge.

summerizerRegional context and strategic effect

  • Iran can threaten shipping through the Strait of Hormuz with naval mines, and even a small number of laid mines can function like a toll booth by forcing ships to accept Iranian control over safe passage.
  • No mine strikes are confirmed in the transcript at this point, but the mine threat alone is enough to deter commercial traffic because ships do not need proof of a live minefield to avoid the route.
  • Mine clearance is slow, dangerous, and difficult, so reopening the strait after even limited mining is much harder than preventing the mining in the first place.

How mines are laid

  • Naval mines can be laid from almost any vessel, including small boats, landing craft, merchant ships, helicopters, submarines, and in some cases rockets.
  • A vessel does not need to be a purpose-built minelayer, because simple rails or improvised handling arrangements are enough to roll mines into the water.
  • The large volume of Iranian-linked small craft and commercial traffic in and around the strait creates many opportunities to sow mines without relying on a specialized platform.

Moored contact and influence mines

  • The Maham-1 is a traditional moored contact mine with horns that detonate on impact, and most variants carry about 120 kg of explosive while a smaller shallow-water version carries about 20 kg.
  • These moored mines sink an anchor to the seabed and then float the charge body a few meters below the surface, where they are harder to see and well placed to strike deep-draft tankers.
  • The Maham-3 keeps the same general moored arrangement but uses acoustic and magnetic influence fusing, so it can detonate without direct contact and can sit deeper beneath a ship.
  • Influence fusing also allows delayed arming, long persistence, and ship counters that let a mine ignore earlier vessels and wait for a later target.

Bottom and specialty mines

  • The Maham-2 is a bottom influence mine with a much larger warhead of roughly 350 kg, better concealment on the seabed, and greater resistance to old-style cable-cutting sweeps.
  • Bottom influence mines are harder to certify as cleared because a live mine can remain on the bottom after multiple ships pass overhead if its counter has not yet reached its programmed number.
  • Iran also has a self-propelled bottom-mine concept in which a torpedo-like propulsion unit carries the weapon 10 to 20 km before it settles on the seabed.
  • A fiberglass-cased conical bottom mine copied from the Italian Manta adds another concealment problem because its nonmetallic body is harder to detect and it is suited to shallow water.
  • Rocket-laid mines using a Fajr-5 type launcher trade warhead size and depth effectiveness for very long standoff placement, making them more useful for anchorages, coastal approaches, and gap-filling than for the deepest main channel.
  • A Chinese EM-52 type rising mine would be the most dangerous system mentioned because it can sit deep on the seabed, sense a target, launch upward, and attack laterally from significant distance.

Clearance and operational impact

  • Traditional wire sweeps can still cut the mooring cables of older floating mines, but they do not solve the problem posed by bottom influence mines.
  • Counters, arming delays, mixed mine types, and uncertainty about where mines were laid all expand the time needed to reopen shipping lanes.
  • A handful of mines is enough to almost paralyze traffic because every transit becomes a gamble and every clearance declaration remains open to doubt.

Other Iranian anti-shipping threats

  • Mines are only one layer of the threat, alongside anti-ship ballistic missiles, USVs, drones, artillery, small-boat attacks, and anti-ship missiles.
  • USVs are identified as the main immediate threat to ships, while mines are identified as the hardest threat to clear once they are in the water.
  • Anti-ship missiles, drones, and small boats can damage or harass shipping, but mines have the strongest ability to keep sea lanes closed over time.

Strategic escalation beyond Hormuz

  • Control pressure in the Strait of Hormuz changes the waterway from open international transit into a passage shaped by Iranian coercion over who sails and on what terms.
  • The pressure can spread beyond Hormuz because Iran can encourage Houthi attacks in the Red Sea and thereby threaten both ends of the wider regional tanker route.
  • Combined disruption in Hormuz, Bab el-Mandeb, and the approaches to Suez creates a broader maritime dilemma than a single chokepoint crisis.

References

https://www.youtube.com/watch?v=TMXSDUj-dms

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