The chemical dynamics of marine dissolved organic nitrogen (DON), a reservoir featuring surface accumulations even in areas where nitrogen limits productivity, have yet to be resolved. We exploited differences in the acid lability of amide bonds within high-molecular-weight (HMW) DON to show that vertical DON profiles result in part from the presence of two chemically distinct pools of amide. Half of HMWDON in surface waters is present as N-acetyl amino polysaccharides. In contrast, nearly all deep-sea HMWDON, and therefore, most HMWDON, is present in amides that resist both chemical hydrolysis and biological degradation.
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http://dx.doi.org/10.1126/science.1108925 | DOI Listing |
ACS Nano
January 2025
Institute of Photonics and of Nanotechnologies- National Researcher Council (IFN-CNR), LNESS Laboratory, Piazza Leonardo Da Vinci 32, 20133 Milano, Italy.
Manipulating the optical landscape of single quantum dots (QDs) is essential to increase the emitted photon output, enhancing their performance as chemical sensors and single-photon sources. Micro-optical structures are typically used for this task, with the drawback of a large size compared to the embedded single emitters. Nanophotonic architectures hold the promise to modify dramatically the emission properties of QDs, boosting light-matter interactions at the nanoscale, in ultracompact devices.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Research Center of Resource Chemistry and Energy Materials, Key Laboratory of Clay Mineral of Gansu, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, P.R. China.
Clay minerals show significant potential as fillers in polymer composite solid electrolytes (CSEs), whereas the influence of their microstructures on lithium-ion (Li) transport properties remains insufficiently understood. Herein, we design advanced poly(ethylene oxide) (PEO)-based CSEs incorporating clay minerals with diverse microstructures including 1D halloysite nanotubes, 2D Laponite (Lap) nanosheets, and 3D porous diatomite. These minerals form distinct Li transport pathways at the clay-PEO interfaces due to their varied structural configurations.
View Article and Find Full Text PDFPest Manag Sci
January 2025
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
Background: Bactrocera cucurbitae (Coquillett) is a distructive quarantine insect pest that causes significant economic losses on cucurbit crops. To explore a green control approach, we investigated the behavioral responses of B. cucurbitae larvae and adults to bacterial suspensions, sediments, and supernatants derived from eight gut microbial strains across four distinct genera.
View Article and Find Full Text PDFAdv Mater
January 2025
Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, China.
Cancer immunotherapy, which leverages immune system components to treat malignancies, has emerged as a cornerstone of contemporary therapeutic strategies. Yet, critical concerns about the efficacy and safety of cancer immunotherapies remain formidable. Nanotechnology, especially polymeric nanoparticles (PNPs), offers unparalleled flexibility in manipulation-from the chemical composition and physical properties to the precision control of nanoassemblies.
View Article and Find Full Text PDFFoods
January 2025
Institute of Food and Beverage Innovation, Zurich University of Applied Sciences, Einsiedlerstrasse 35, 8820 Wädenswil, Switzerland.
Palm and palm kernel oils are preferred ingredients in industrial food processing for baked goods and chocolate-based desserts due to their unique properties, such as their distinctive melting behaviors. However, ongoing concerns about the social and environmental sustainability of palm oil production, coupled with consumer demands for palm oil-free products, have prompted the industry to seek alternatives which avoid the use of other tropical or hydrogenated fats. This project investigated replacing palm oils with chemically unhardened Swiss sunflower or rapeseed oils.
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