The Japanese government wants to sharply increase the number of launches despite struggles with both current and new launch vehicles.
The post Japan seeks to ramp up launch activity appeared first on SpaceNews.
As the United States of America celebrated its 250th birthday on terra firma with fireworks displays this weekend, two Asian countries made some splashes of their own farther from Earth.
On Sunday, an aging Japanese spacecraft named Hayabusa2, which completed its initial sample-return objective more than half a decade ago, found success with an extended mission that saw the vehicle fly by a peanut-shaped asteroid named Torifune.
Hours later, the Chinese space agency released images from a spacecraft, Tianwen-2, arriving at its target asteroid following a journey of 1 billion km. At this small asteroid, the Chinese spacecraft will attempt to retrieve samples and return them to Earth late next year.
© JAXA
Before the prefrontal cortex evolved, another system in the brain may already have been directing attention, scientists have now revealed.
In a recent study published in Nature Communications, researchers at Johns Hopkins University have identified a small group of brainstem neurons that act as an internal attention filter.
When these neurons were deactivated in mice, the animals became highly distractible, mirroring one of the hallmark features of ADHD. Restoring activity in these neurons allowed the mice to regain normal focus.
Selective spatial attention is the brain’s ability to focus on relevant information while ignoring distractions. This process allows a person to follow a conversation in a noisy environment or recognize a familiar face in a crowd. Conditions such as ADHD and autism also often involve disruptions in selective attention. For many years, scientists believed the prefrontal cortex was primarily responsible for this function.
However, this view does not fully explain how attention works across different species. Primates have a well-developed prefrontal cortex, while other vertebrates have a less pronounced version, yet birds, fish, and turtles still effectively focus their attention.
“If we really go back in evolution, for hundreds of millions of years, birds have had this ability, fish have had this ability. And they do not typically have a highly developed prefrontal cortex, so how does the brain solve this problem?” said lead author Ninad Kothari, a postdoctoral fellow in Johns Hopkins’ Department of Psychological and Brain Sciences. “We were able to identify an evolutionarily old region in the brainstem which affords this ability.”
The researchers traced this behavior to a network of inhibitory neurons located deep within the brainstem, a region found in all vertebrates. Mysore’s laboratory had previously studied this area in birds, frogs, and turtles before examining it in mice.
The team created an attention task, similar to those used in human studies, to test the role of these neurons. Mice viewed visual cues on a screen and earned rewards for responding to a target in front of them while ignoring a distracting signal off to the side. This test measured how well the mice could pick out important information and ignore distractions. The mice successfully performed the task until researchers deactivated the brainstem neurons, at which point they became easily distracted.
Before concluding that these neurons controlled attention, the researchers tested for other possible explanations, such as vision or motor problems, that might account for the mice’s behavior. However, the researchers ruled out these alternative explanations.
“The only thing impaired was their ability to take the competing pieces of information, compare them, and pay attention to the location with the most important information,” said senior author Shreesh Mysore, a neuroscientist who studies neural circuits tied to behavior. “This part of the brain is like an attentional selection engine. It helps solve the question: ‘What is most important information I should pay attention to right now?'”
The attention deficit was not permanent. When the neurons were reactivated, the same mice that had previously been unable to ignore faint distractions were once again able to ignore even strong distractors.
“A hallmark of ADHD is that even faint distractors draw attention away — and that’s exactly what we see here when these neurons are silenced,” Mysore said. “But the very next day, when the neurons are turned back on, the same animal can ignore distractors again, even very strong ones.”
“All the evidence to date suggests that these neurons exist in humans too,” Mysore said. “But are they responsible for selective spatial attention in humans? An exciting hypothesis is that they play a crucial role.”
If researchers find that these neurons function differently in people with attention disorders, the circuit could become a target for future therapies.
Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds an MBA, a Bachelor of Science in Business Administration, and a data analytics certification. His work focuses on breaking scientific developments, with an emphasis on emerging biology, cognitive neuroscience, and archaeological discoveries.
A butterfly that survives for nearly a year, while its closest relatives live only two weeks, offers a potential model for studying how aging and lifespan can evolve in nature.
A University of Bristol-led study published in Nature Communications reports that some Heliconius butterflies have evolved both longer lifespans and slower physical decline, distinguishing them from most other butterfly species studied to date.
Heliconius butterflies inhabit the rainforests of Central and South America, where most adult butterflies live only a few weeks. In the study, Heliconius hewitsoni reached a maximum lifespan of 348 days, while a related species, Dione juno, only survived about 14 days under observed conditions. This represents a 25-fold difference in maximum lifespan between two closely related species.
Heliconius butterflies not only live longer than their relatives, but also show slower physical decline with age. The team, in collaboration with the Smithsonian Tropical Research Institute in Panama, measured grip strength in aging butterflies to assess physical decline. Older Heliconius hecale performed as well as the younger individuals tested, showing no detectable age-related decline in grip strength.
The team combined butterfly house data, mark–recapture field studies, and controlled lab experiments. In these cases, Heliconius butterflies consistently showed longer lifespans, lower mortality rates, and slower rates of aging than closely related species that do not feed on pollen.
One hypothesis for their extended lifespan focuses on their unusual adult diet. While most butterflies feed only on nectar, Heliconius also consumes pollen, which was thought to provide the nutritional basis for its extended lifespan.
To test this idea, researchers compared pollen-feeding Heliconius hecale with its non-pollen-feeding relative, Dryas iulia. H. hecale maintained body mass and muscle performance longer than D. iulia. Even without pollen in its diet, H. hecale still outlived its relative by a wide margin. This suggests that diet alone does not explain Heliconius’s extended lifespan.
Dr. Jessica Foley, the study’s lead author from the University of Bristol’s School of Biological Sciences, explained that insects already show a huge range of lifespans. Some, like mayflies, live only a few days, while ant and termite queens can survive for decades. “This represents a roughly 5,000-fold difference within the class, compared with around a 100-fold difference in lifespan observed in mammals.”
Heliconius butterflies are notable because they have evolved both longer lifespans and slower rates of aging, allowing them to outlive close relatives from which they diverged only recently in evolutionary history.
Most aging research uses a limited set of laboratory organisms, such as mice, worms, and fruit flies, to study biological aging mechanisms. The heliconius butterfly provides a unique opportunity to study a long-lived species closely related to short-lived species, allowing for direct comparison in a natural context. Foley noted that comparing these two groups “can help reveal how lifespan is extended, making them a highly promising new model for research into the biology of aging and longevity.”
If pollen feeding and longevity evolved together but are not entirely dependent on each other, the next step is to identify the genetic and physiological changes responsible for both traits. Understanding these mechanisms in Heliconius butterflies could provide insight into how aging evolves across species.
Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds an MBA, a Bachelor of Science in Business Administration, and a data analytics certification. His work focuses on breaking scientific developments, with an emphasis on emerging biology, cognitive neuroscience, and archaeological discoveries.
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