September 23, 2024: We're covering uterus transplants, tiling chaos and claims that life on Earth was inevitable. —Robin Lloyd, Contributing Editor | | | Experts in obstetrics and gynecology have succeeded in transplanting more than 100 human uteruses in the past decade or so, which have led to dozens of births, reports Scientific American editor Tanya Lewis. These advances may give new hope for pregnancy to people with a damaged or abnormal uterus, as well as people without any such organ. In an evaluation of 20 people with uterine infertility who then received a transplanted uterus, 14 surgeries were successful and all 14 resulted in a live birth.
How it works: Such transplants involve two surgeries: one to remove the donor's uterus and supporting blood vessels, and another to implant them in the recipient. Some months later, pregnancy can be achieved through in-vitro fertilization and babies are delivered by cesarean section. Recipients have to take organ-rejection drugs. To reduce the long-term risk posed by those medications, "the transplanted uterus is surgically removed after one or two pregnancies," Lewis writes.
What the experts say: Infertility related to uterine conditions afflicts about one in 500 women of reproductive age. And thousands of people assigned female at birth are born without a uterus. Cancer, damage during childbirth and abnormalities in the uterus also can prevent successful pregnancy. Many of these people, nonetheless, have functional ovaries and eggs.
| | | Fields Medal-winning mathematician Terence Tao and a colleague have disproved a long-standing geometric conjecture related to tiling. An example in two dimensions would be installing tiles on a never-ending bathroom floor, and one in three dimensions would be tightly packing an infinitely large car trunk. The conjecture held that, in any dimension, fully covering a space without gaps and without rotating or flipping a tile—such properties are called constraints—would involve the use of repeating tile patterns, known as periodic tiling. By translating the problem from a geometric one into an algebraic one, the team up-ended the conjecture and showed that sufficiently high-dimensional spaces can be fully tiled without relying on a regular pattern, that is, aperiodically, reports applied mathematician Max Springer.
How they did it: The team's finding involved adding constraints, in the form of dimensions, to the space to be tiled, Springer reports. Additional constraints worked to shrink the number of solutions for each tile placement, much like entering each subsequent number in a Sudoku puzzle further constrains the possible numbers to fill in remaining empty squares. The team's counterexample functioned in very high-dimensional space. Rather than operating in three- or four-dimensions, it operated in a space with a dimensional number made of 100,000 digits.
What the experts say: "High-dimensional tilings are enormously complex. The situation seems much better behaved in low-dimensional [space], with three dimensions being the current frontier of research," says Tao. | | | Christoph Hetzmannseder/Getty Images | | | An imagined exoplanet surface may contain the ingredients for a spark of life. gremlin/Getty Images | | | • Assertions and claims related to the question of life elsewhere in the universe often depend on unproven theories for how life arose on Earth and unknown probabilities for life emerging on exoplanets, write astrophysicist Mario Livio and chemist Jack Szostak. So the best answers to extraterrestrial life questions likely involve astrophysical searches for it in the Milky Way, the authors assert. | 4 min read | | | A cat that was separated from its California-based humans this summer in Yellowstone National Park somehow traveled some 800 miles to a town within 200 miles of its home. Authorities returned the cat to the Roseville couple by relying on the microchip implanted in the seal point mitted siamese cat. Dog journeys and intelligence tend to draw more attention than those of cats. But cats' minds and abilities are fascinating unto themselves, as Scientific American editor Kate Wong explores in this interview with John Bradshaw, author of Cat Sense (Bradshaw also wrote the book Dog Sense). For those of us who don't bring our cats on vacations and generally keep cats indoors, I also recommend Mikel Maria Delgado's recent book Play with Your Cat!. | —Robin Lloyd, Contributing Editor | | Subscribe to this and all of our newsletters . | | | | Scientific American
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