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Jellyfish

Jellyfish are marine invertebrates belonging to the Scyphozoa class, and in turn the phylum Cnidaria. The body of an adult jellyfish is composed of a bell-shaped, jellylike substance enclosing its internal structure, from which the creature's tentacles suspend. Each tentacle is covered with stinging cells (cnidocytes) that can stun or kill other animals: most jellyfish use them to secure prey or as a defense mechanism. Others, such as Rhizostomae, do not have tentacles at all.

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Health & Medicine News

April 28, 2026

Scientists at MIT discovered that chaotic laser light can spontaneously form a highly focused beam instead of scattering—if the conditions are just right. This “pencil beam” enabled them to image the blood-brain barrier in 3D at speeds 25 ...
A daily vitamin D supplement may quietly supercharge chemotherapy. In a small study, women who took low doses alongside treatment were far more likely to see their cancer vanish than those who didn’t. Since vitamin D also supports immune ...
Researchers have found an enzyme that can turn fragile drug molecules into durable ring shapes. This could help medications like Ozempic last longer and work more effectively. The process is simpler and more precise than traditional methods, even ...
A new study reveals that internalizing stress—especially feelings of hopelessness—may significantly speed up memory decline in older Chinese Americans. Surprisingly, factors like community support didn’t show the same impact. Researchers say ...
Scientists are making a major leap toward freezing organs for future use without damaging them. A new study reveals that one of the biggest obstacles—cracking during ultra-cold preservation—can be reduced by carefully tuning the temperature at ...
Deep within the brain, scientists have uncovered a hidden “switch” that may decide whether pain fades away—or lingers for months or even years. Researchers found that a small, little-known region called the caudal granular insular cortex ...
A major new study finds that living in pesticide-heavy environments could raise cancer risk by up to 150%, even when the chemicals are considered “safe” on their own. The research suggests these mixtures may silently damage cells years before ...
Mixing up your workouts might be the real secret to a longer life. Long-term research tracking over 100,000 people for more than three decades suggests that doing a variety of physical activities—rather than just more of the same—can ...
Fish oil has long been praised as brain-boosting, but new research suggests the story may be more complicated. Scientists found that in people with repeated mild head injuries, a key omega-3 fatty acid in fish oil—EPA—may actually interfere with ...
Scientists have uncovered how graphene oxide pulls off a remarkable trick: it hunts down and destroys harmful bacteria while leaving human cells completely unharmed. By targeting a molecule found only in bacterial membranes, this ultra-thin ...
A gut bacterium may be quietly fueling depression through an unexpected chemical twist. Researchers found that when Morganella morganii interacts with a common pollutant, it produces a molecule that ...
A newly confirmed mass grave in ancient Jordan offers chilling insight into one of history’s first pandemics. Hundreds of plague victims were buried within days, revealing how the Plague of Justinian devastated entire communities. The findings ...

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