Researchers have designed a liquid hydrogen storage and delivery system that could help make zero-emission aviation a reality. Their work outlines a scalable, integrated system that addresses several engineering challenges at once by enabling hydrogen to be used as a clean fuel and also as a built-in cooling medium for critical power systems aboard electric-powered aircraft.

Researchers find that iron powder, an inexpensive alternative to activated carbon, does a better job at filtering PFOS from water -- it's 26 times more effective.

Researchers found that digestion in hawks and owls can alter the results of isotopic analysis in pellets and droppings.

A pioneering method to simulate how microscopic particles move through the air could boost efforts to combat air pollution, a study suggests.

Most people have witnessed -- or rather smelled -- when a protein enzyme called sulfite reductase works its magic. This enzyme catalyzes the chemical reduction of sulfite to hydrogen sulfide. Hydrogen sulfide is the rotten egg smell that can occur when organic matter decays and is frequently associated with sewage treatment facilities and landfills. But scientists have not been able to capture a visual image of the enzyme's structure until now, thus limiting their full understanding of how it works.

A new study has found that a smartphone app that tracks household water use and alerts users to leaks or excessive consumption offers a promising tool for helping California water agencies meet state-mandated conservation goals. The study found that use of the app -- called Dropcountr -- reduced average household water use by 6%, with even greater savings among the highest water users.

Researchers conducted a systematic review of 99 scientific publications that compared the flora or fauna of old-growth forests, managed forests and clearcut sites in boreal Europe. The reviewed studies showed large differences in the species communities inhabiting these forest types. The species richness of full-canopy forests increases as the forest gets older. Clearcut sites are also species-rich, but they are inhabited by a distinct set of species in comparison to full-canopy forests.

When formulating climate policy, too little attention is paid to social factors and too much to technological breakthroughs and economic reasons. Because citizens are hardly heard in this process, European governments risk losing public support at a crucial moment in the climate debate.

Scientists, who have spent more than a decade examining the impact of artificial light at night on the world's coasts and oceans, have shown that more than one-fifth of the global ocean -- an area spanning more than 75 million sq km -- has been the subject of ocean darkening over the past two decades. Ocean darkening occurs when changes in the optical properties of the ocean reduce the depth of its photic zones, home to 90% of all marine life and places where sunlight and moonlight drive ecological interactions.

Alterations to the diet of pests could impact how quickly they can adapt to biopesticides.

Scientists have discovered cells in the skin of Atlantic salmon that offer new insights into how wounds heal, tissues regenerate, and cellular transitions support long-term skin health.

In the long battle to create an effective HIV vaccine, scientists have made a major leap forward. A new study shows that a series of vaccines can coax the immune system to produce powerful antibodies capable of blocking a wide range of HIV strains -- including those that are typically the hardest to stop.

Humans were making tools from whale bones as far back as 20,000 years ago, according to a new study. This discovery broadens our understanding of early human use of whale remains and offers valuable insight into the marine ecology of the time.

Contrary to widespread assumptions, the largest shark that ever lived -- Otodus megalodon -- fed on marine creatures at various levels of the food pyramid and not just the top. Scientists analyzed the zinc content of a large sample of fossilized megalodon teeth, which had been unearthed above all in Sigmaringen and Passau, and compared them with fossil teeth found elsewhere and the teeth of animals that inhabit our planet today.

Flowers grow stems, leaves and petals in a perfect pattern again and again. A new study shows that even in this precise, patterned formation in plants, gene activity inside individual cells is far more chaotic than it appears.

A gene that regulates the development of roots in vascular plants is also involved in the organ development of liverworts -- land plants so old they don't even have proper roots. The discovery highlights the fundamental evolutionary dynamic of co-opting, evolving a mechanism first and adopting it for a different purpose later.

In biology, enzymes have evolved over millions of years to drive chemical reactions. Scientists have now derived universal rules to enable the de novo design of optimal enzymes. As an example, they considered the enzymatic reaction of breaking a dimer into two monomer molecules. Considering the geometry of such an enzyme-substrate-complex, they identified three golden rules that should be considered to build a functional enzyme.

Daylight can boost the immune system's ability to fight infections.

Plankton may be tiny, but they play an important role in the ocean. As the foundation of marine ecosystems, they support ocean food webs and help regulate Earth's climate by storing carbon. While lab studies have shown plankton can adjust their chemistry in response to environmental changes, a new global study reveals how these adaptations occur in the real ocean.

A group of fossils of elasmosaurs -- some of the most famous in North America -- have just been formally identified as belonging to a 'very odd' new genus of the sea monster, unlike any previously known. This primitive 85-million-year-old, 12 meter-long, fiercely predatory marine reptile is unlike any elasmosaur known to-date and hunted its prey from above.