Advanced light microscopy techniques have come into their own — and are giving scientists a new understanding of human biology and what goes wrong in disease
Using a tiny, spherical glass lens sandwiched between two brass plates, the 17th century Dutch microscopist Antonie van Leeuwenhoek was the first to officially describe red blood cells and sperm cells in human tissues, and observe “animalcules” — bacteria and protists — in the water of a lake.
The strait lies between Iran and its Gulf Arab neighbours and is used to transport about 20 million barrels per day of oil – the equivalent of 20% of global daily oil consumption.
Since 2020, this critical route has been used to transport an average of 14.8 million barrels a day of crude oil and natural gas liquids, 5.5 million barrels a day of petroleum products and 10.8 billion cubic feet per day of LNG.
When we read about the Greco-Roman world, we often hear the stories of famous and wealthy men and women. But the letters of ordinary people, preserved on papyri in Egypt, show us what they were thinking and doing. Human nature, their contents suggest, hasn’t changed much.
Sometime in the 3rd century AD, in Egypt, a man called Zoilus wrote a letter to his mother Theodora about family news. He had just visited his sister Techosous, who was sick:
Zoilus to my mother Theodora, greetings. When I arrived in Thallou today, I found everyone at my brother’s house in good health. But my sister Techosous is fearfully ill, and I expect that she will give birth today to a seven months’ baby. If then she comes through it successfully, I will let you know what happened…
- Detalii
- de: Konstantine Panegyres
- Ştiri ştiinţă - engleză
It’s not a new concept, but it’s a powerful one.
So, how do we go about this? If we consider Earth’s age as 4.54 billion years and divide it by 365 days, each day of the Gregorian calendar represents about 12.438 million years.
To understand the origins of multicelled life, researchers are studying a motley assortment of simpler animal relatives. The commonalities they’re unearthing offer a trove of clues about our mutual past.
Your cells are dying. All the time. Some go gently into the night. Others die less prettily in freak accidents or deadly invasions, or after a showy display.
They can die by accident if they’re injured or infected. Alternatively, should they outlive their natural lifespan or start to fail, they can carefully arrange for a desirable demise, with their remains neatly tidied away.
We hear a lot about women’s biological clock and how age affects the chance of pregnancy.
New research shows men’s fertility is also affected by age. When dads are over 50, the risk of pregnancy complications increases.
Data from more than 46 million births in the United States between 2011 and 2022 compared fathers in their 30s with fathers in their 50s.
While taking into account the age of the mother and other factors known to affect pregnancy outcomes, the researchers found every ten-year increase in paternal age was linked to more complications.
To pee or not to pee? That is a question for the bladder — and the brain. How do we sense the need to urinate? The basic urge is surprisingly complex and can go awry as we age.
A simplified representation of some of the nerve pathways and brain regions that allow most healthy people to detect when the bladder is filling or full, predict how long they can wait to urinate, and successfully carry out a plan to “hold it” or “go.” Disruptions at any level of this complex, two-way system of neuronal communication can lead to bladder disorders, as millions of people worldwide know firsthand.
You’re driving somewhere, eyes on the road, when you start to feel a tingling sensation in your lower abdomen. That extra-large Coke you drank an hour ago has made its way through your kidneys into your bladder. “Time to pull over,” you think, scanning for an exit ramp.
To most people, pulling into a highway rest stop is a profoundly mundane experience. But not to neuroscientist Rita Valentino, who has studied how the brain senses, interprets and acts on the bladder’s signals. She’s fascinated by the brain’s ability to take in sensations from the bladder, combine them with signals from outside of the body, like the sights and sounds of the road, then use that information to act — in this scenario, to find a safe, socially appropriate place to pee. “To me, it’s really an example of one of the beautiful things that the brain does,” she says.
Researchers are figuring out the features of these foods that harm our health — and proposing ways ahead.
From breakfast cereals and protein bars to flavored yogurt and frozen pizzas, ultraprocessed foods are everywhere, filling aisle upon aisle at the supermarket. Fully 58 percent of the calories consumed by adults and 67 percent of those consumed by children in the United States are made up of these highly palatable foodstuffs with their highly manipulated ingredients.
And ultraprocessed foods are not just filling our plates; they’re also taking up more and more space in global conversations about public health and nutrition. In the last decade or so, researchers have ramped up efforts to define ultraprocessed foods and to probe how their consumption correlates to health: A wave of recent studies have linked the foods to heightened risk for conditions ranging from cardiovascular disease and cancer to obesity and depression.
In a recent Instagram post, the actor Jameela Jamil revealed she has poor bone density, despite only being in her 30s. Jamil blamed this finding on 20 years of dieting – urging her followers to be aware of the harms diet culture can do to your health.
Typically, this soilless cultivation happens in huge greenhouses or warehouses, with plants stacked high on rows and rows of shelves. Parameters such as lighting, temperature and humidity can be controlled by computer systems, so vertical farming is sometimes called controlled environment agriculture.
There are three types of vertical farming. In hydroponics, plant roots are held in a liquid nutrient solution. In aeroponics, roots are exposed to the air and a nutrient-rich mist or spray is applied to the roots. In aquaponics, nutrients from fish farm waste replace some or all of the chemical fertilisers being delivered to plants through hydroponics.
There’s huge scope to produce a lot of food using these methods of cultivation but there are four key myths about vertical farming that need to be dispelled:
Hundreds of thousands of people worldwide are taking drugs like Ozempic to lose weight. But what do we actually know about them?
Drugs like Ozempic are very effective at helping most people who take them lose weight. Semaglutide (sold as Wegovy and Ozempic) and tirzepatide (sold as Zepbound and Mounjaro) are the most well known in the class of drugs that mimic hormones to reduce feelings of hunger.
Diabetes, weight loss and now heart health: A new family of drugs is changing the way scientists are thinking about obesity — and more uses are on the horizon
Few drugs have achieved the stardom that semaglutide, marketed in the United States as Ozempic or Wegovy, has today. A synthetic, injectable version of an intestinal hormone, it is the flagship of a new category of drugs initially developed for diabetes that rose to fame in the medical and public arena as an effective weapon against obesity. Semaglutide has proved so successful that its manufacturer, the Danish company Novo Nordisk, is unable to keep up with demand.
Certain groups of people are at greater risk of not getting enough vitamin D. Here are some of them.
Nutritional science is supposed to chart a course to our healthier selves. But contradictory scientific results and interpretations can muddy the waters — and few nutrients have recently demonstrated that more clearly than vitamin D.
At one point, it seemed that everyone should be taking vitamin D supplements, and that doing so would protect against a whole host of maladies, from bone problems to heart disease and cancer. More recently, new studies appear to have debunked many of those claims.
But a closer look at the research reveals a more nuanced message around vitamin D supplements: They can be key to correcting deficiencies, though people who already have enough — which is most of the American public — are generally unlikely to see benefits from taking large doses. Experts have come to worry about supplement enthusiasts overdosing in the belief that more is better or, at the other extreme, some nutrient-deprived people shunning them altogether.
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