Oxytocin drives childbirth through a feedback loop where each contraction triggers the next

the gist

Oxytocin is a peptide hormone and neuropeptide made in the hypothalamus and released by the posterior pituitary. In humans it is involved in social bonding, romantic attachment, sexual activity, childbirth and breastfeeding. Its most dramatic action is in labour: it stimulates uterine contractions, and the process runs on positive feedback. Each contraction releases oxytocin, which prompts the body to make and release more, which strengthens and speeds up the next contraction. The loop continues until the triggering activity stops, meaning the baby has been delivered or the stimulus has ended. A similar loop operates during breastfeeding and sexual activity, which is why oxytocin is so closely associated with bonding.

how it works

Stretching of the cervix and uterine contractions trigger oxytocin release from the posterior pituitary. The hormone then acts on the uterine muscle to contract it more strongly, and it also stimulates further oxytocin production in the hypothalamus. This self-reinforcing cycle intensifies labour until it stops.

so what

Oxytocin is one of the few hormones that works through positive feedback, which explains how labour can accelerate so quickly. Doctors use synthetic oxytocin to speed up delivery or control bleeding after birth.

fun fact

Oxytocin is often nicknamed the 'love hormone', although the name captures only part of its roles.

From Wikipedia, the free encyclopedia · text CC BY-SA 4.0

Image: Wikimedia Commons

source: Wikipedia ↗

historyWikipediaclassic1336–1565 · Karnataka, India

Hampi was once one of the world's largest cities, until its Vijayanagara capital was destroyed in 1565

the gist

Hampi is a UNESCO World Heritage Site in Karnataka, India, with more than 1,600 surviving remains spread over 4,100 hectares. It was the capital of the Vijayanagara Empire from 1336 to 1565. Travellers from Persia and Portugal described it as a prosperous, wealthy and grand city with temples, markets and farms along the Tungabhadra River. By 1500 it was estimated to be the world's second-largest city after Beijing, and probably India's richest at the time. In 1565 a coalition of Muslim sultanates defeated the Vijayanagara Empire, its capital was conquered and destroyed, and the city was left in ruins. Hampi remains a religious centre, with the active Virupaksha Temple at its heart.

how it works

The city was built around a fortified core with temples, markets and water structures along the river, supplied by an extensive network of roads and waterworks. When the empire fell, the city was not rebuilt, so its stone monuments were left standing.

so what

Hampi shows how quickly a great city can vanish after a military defeat, and how a ruined capital can remain sacred. Its ruins give historians a view of medieval South Asia that few other sites can match.

fun fact

The name Hampi comes from Pampa, an old name for the Tungabhadra River.

From Wikipedia, the free encyclopedia · text CC BY-SA 4.0

Image: Wikimedia Commons

source: Wikipedia ↗

2 min

politicsshortCNA2:01

False allegations about Singapore’s hand in Indonesia’s markets and a made-up meeting

from CNA

CNA Verify has found close to 400 posts pushing falsehoods tying Singapore to Indonesia’s stock market rout and to a secret meeting that never took place. Together, they drew nearly 12 million views, and some were circulated by accounts that appeared to be working in concert, across multiple social media platforms.

Here’s how the disinformation campaign targeting Singapore was uncovered.

on YouTube: CNA ↗