Tag: science

Parthogenesis

Can’t wait until MRA losers figure this out

Remember Dolly, the cloned sheep? Back in Glory Season, I speculated that it would be difficult to clone mammals and that hence there might still be some (slight) need for males, even in a hyper feminist world. Well, we’ve seen some ups and downs since. Dolly seemed to suggest that tech empowered female humans will be able to dispense with us hairy-inseminators in the future – and at times I admit, I wouldn’t blame em.

Only then Dolly died young, sickened with many diseases of aging and with shortened chromosomes, suggesting that a cloned mammal inherits some of the aging clock of the parent and does not reset its embryonic timer back to zero! Baaaah! So much for parthenogenesis and eliminating males.

Only now … another reversal! It seems 12 more Dolly clones are doing just fine, with no sign of premature senescence. So maybe it just took a better process. Sorry guys. Your services are no longer needed. (Except maybe for amusement and moving some furniture, now and then.) Try to tidy up a bit on your way out, hm?

2023-07-31:

For the first time, scientists have used genetic engineering to trigger ‘virgin birth’ in female animals that normally need a male partner to reproduce.

Previously, scientists have generated young mice and frogs with no genetic input from a male parent. But those offspring were made by tinkering with egg cells in laboratory dishes rather than by giving female animals the capacity for virgin birth, also known as parthenogenesis.
To identify the genes that underlie parthenogenesis, Sperling and her colleagues sequenced the genomes of two strains of the fly Drosophila mercatorum: one that reproduces sexually and another that reproduces through parthenogenesis. The researchers then compared gene activity in eggs from flies capable of parthenogenesis with that in eggs from flies capable of only sexual reproduction to identify the genes at work during one process but not the other.

The comparison allowed the authors to identify 44 genes that were potentially involved in parthenogenesis. The researchers altered the equivalent genes in the fruit fly Drosophila melanogaster, which usually cannot reproduce asexually.

After altering various combinations of genes, the scientists hit on a combination that induced parthenogenesis in 11% of female fruit flies. Some of the offspring of these genetically engineered flies were also capable of parthenogenesis.

Although the parthenogenetic flies received genes only from their mothers, they weren’t always clones of their parent. Some had 3 sets of chromosomes, whereas eggs laid by mothers reproducing through parthenogenesis usually have only 2.

Model Organisms

Biology needs a taste of Morgan’s pre-fly days, when scientists studied a panoply of organisms. By focusing on 7 animals out of 9m species on Earth, we are missing a huge chunk of interesting biology. “We are due for a renaissance. We have narrowed our focus to a handful of organisms that statistically are highly unlikely to encompass the gamut of biological activity on the planet.”

1D transistor

With silicon transistors, the entire device is either turned on or off. With 2-D transistors, by contrast, Lai and the team found that electric currents move in a more phased (or wave-like) way, beginning first at the edges before appearing in the interior. This suggests the same current could be sent with less power and in an even tinier space — using a 1-dimensional edge instead of the 2-dimensional plane.

The Lazarus File

In 1986, a young nurse named Sherri Rasmussen was murdered in Los Angeles. Police pinned down no suspects, and the case gradually went cold. It took 23 years—and revolutionary breakthroughs in forensic science—before LAPD detectives could finally assemble the pieces of the puzzle. When they did, they found themselves facing one of the unlikeliest murder suspects in the city’s history. When Lazarus arrived in the interrogation room, Stearns and Jaramillo abandoned the story of a suspect talking about stolen art, and explained that her name had come up in a case involving an ex-boyfriend of hers, John Ruetten. Knowing she was married to someone else, they’d selected a place where they could speak privately, away from gossiping colleagues. Stearns and Jaramillo interviewed Lazarus for more than 1 hour, coming at her in an oblique manner that left it unclear whether they were speaking with her as a possible witness or a criminal suspect. The conversation meandered, but every digression led back, inevitably, to the murder of Sherri Rasmussen. It was only after Jaramillo asked Lazarus if she’d be willing to give them a DNA swab and noted, “It’s possible we may have some DNA at the location,” that she wanted to contact a lawyer. Declaring herself “shocked,” the veteran detective stood and walked out, 68 minutes after she’d sat down. Lazarus got only as far as the jail’s hallway, where she was stopped by other RHD detectives and placed in handcuffs.

Is Infinity Real?

If the physical universe cannot contain infinity (which is a wise default position to have in the absence of extraordinary evidence), there will be limits at which our infinity-laden mathematical models will fail. Our simple problems were meant to explore these limits. We may find that the infinity-based predicted outcome can still hold, but for different reasons (as in the first problem); or that the infinity-based predicted outcome is wrong, and we have to reason differently to reach qualitatively different conclusions (second and third problems).

CPU Neuroscience

But then the biologists tried it out. This paper details an attempt to study the 6502 chip using the tools we have available to study nematode brains and the like, and it’s titled “Could a Neuroscientist Understand a Microprocessor”. I’ll let the abstract speak for itself: There is a popular belief in neuroscience that we are primarily data limited, that producing large, multimodal, and complex datasets will, enabled by data analysis algorithms, lead to fundamental insights into the way the brain processes information. Microprocessors are among those artificial information processing systems that are both complex and that we understand at all levels, from the overall logical flow, via logical gates, to the dynamics of transistors. Here we take a simulated classical microprocessor as a model organism, and use our ability to perform arbitrary experiments on it to see if popular data analysis methods from neuroscience can elucidate the way it processes information. We show that the approaches reveal interesting structure in the data but do not meaningfully describe the hierarchy of information processing in the processor. This suggests that current approaches in neuroscience may fall short of producing meaningful models of the brain.

Gene drives

knowing what gene drives are is crucial to understand the most important and powerful biotechnology yet.

Gene drives work in mice:

In a paper in Nature, biologists demonstrate that gene drive technology also works — at least up to a point — in a mammal: the mouse. Their findings highlight the potential, but also the significant limitations, of putting gene drives to work in the real world. For at least some time to come, these kinds of “active genetics” technologies may be more useful as laboratory tools than as instruments for remaking nature.