Night owls don’t die earlier
Researchers investigating the impact of chronotype – the body’s natural inclination to sleep at a certain time – have found that staying up late at night has little impact on how long ‘night owls’ live.
They did this by analysing health data from a 37-year follow-up study in Finnish adults. In 1981, 22,976 twins completed a questionnaire in which they indicated to what extent they were a morning person or an evening person. The researchers followed-up the participants in 2018.
The chance of dying from any cause was 9% higher among definite night owls compared to early birds, when education, daily alcohol consumption, smoking status and quantity, BMI, and sleep duration were taken into account, but the researchers found that smoking and alcohol largely caused these deaths, not chronotype.
“The increased risk of mortality associated with being a clearly ‘evening’ person appears to be mainly accounted for by a larger consumption of tobacco and alcohol. This is compared to those who are clearly ‘morning’ persons,” says Dr Christer Hublin, from the Finnish Institute of Occupational Health, and co-author of the new paper in the journal Chronobiology International.
Creating engineered human tissue to study mosquito bites
Biomedical engineers have invented a new way to study how mozzies bite and feed, with the ultimate goal of helping to fight deadly mosquito-borne diseases.
They created engineered tissue by lining a 3-dimensional capillary gel biomaterial with human cells, and then infused it with blood.
Mosquitoes feed on UCF-engineered tissue. Credit: University of Central Florida
Tests showed that mosquitoes readily bite and feed on blood from the constructs. Currently, researchers largely rely on animal models and cells cultured in petri dishes for their experiments.
The new system is also promising for feeding mosquito species that have proven difficult to rear and maintain as colonies in the laboratory. The researchers aim to incorporate addition types of cells to move the system closer to human skin in the future. The research was published in the journal Insects.
Slightly lost bumblebees use scent to find their way home
Researchers studying the buﬀ-tailed bumblebee (Bombus terrestris) have found they use their sense of smell (as well as vision) to find their way home. In nature these bumblebees nest in abandoned mouseholes, hidden under grass or leaves.
The new study is in Frontiers in Behavioral Neuroscience.
“Here we show that bumblebees rely on their own scent marks, which they deposit at their nest entrance while leaving for a foraging trip, to find [their way] back home when the visual cues are not sufficiently reliable,” says first author Sonja Eckel, a PhD student at the Department of Neurobiology of Bielefeld University in Germany.
In an enclosed flight arena within the lab, the researchers changed the location of visual landmarks used by the bees to locate their nest. They found that, while bumblebees were confused by the changing visual landmarks, introducing a glass ring carrying bumblebee scent marks allowed the bees to focus on the nest location again.
“Our chemical analysis showed that this scent is a bouquet of hydrocarbons, fatty acids, and other substances, such as esters and alcohols. Many of these substances are known to be used by bumblebees in other behavioural contexts, also by other insect species,” says Eckel.
Scientists discover new spiral-shaped brain signals
Published in Nature Human Behaviour, the findings indicate that these ubiquitous spirals help organise brain activity and cognitive processing.
Visual re-creation of brain spirals travelling across the cortex. Credit: Gong et al.
“Our study suggests that gaining insights into how the spirals are related to cognitive processing could significantly enhance our understanding of the dynamics and functions of the brain,” says Associate Professor Pulin Gong, senior author of the paper from the School of Physics, the University of Sydney, Australia.
“These spiral patterns exhibit intricate and complex dynamics, moving across the brain’s surface while rotating around central points known as phase singularities.
“Much like vortices act in turbulence, the spirals engage in intricate interactions, playing a crucial role in organising the brain’s complex activities.
“The intricate interactions among multiple co-existing spirals could allow neural computations to be conducted in a distributed and parallel manner, leading to remarkable computational efficiency.”