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The long-standing hypothesis that the isotopic composition of plant stem water reflects that of source water is being challenged by studies reporting bulk water from woody stems with an isotopic composition that cannot be attributed to any potential water source. The mechanism behind such source-stem water isotopic offsets is still poorly understood. Using a novel technique to extract selectively sap water from xylem conduits, we show that, in cut stems and potted plants, the isotopic composition of sap water reflects that of irrigation water, demonstrating unambiguously that no isotopic fractionation occurs during root water uptake or sap water extraction. By contrast, water in nonconductive xylem tissues is always depleted in deuterium compared with sap water, irrespective of wood anatomy. Previous studies have shown that isotopic heterogeneity also exists in soils at the pore scale in which water adsorbed onto soil particles is more depleted in deuterium than unbound water. Data collected at a riparian forest indicated that sap water matches best unbound soil water from depth below -70 cm, while bulk stem and soil water differ markedly. We conclude that source-stem isotopic offsets can be explained by micrometre-scale heterogeneity in the isotope ratios of water within woody stems and soil micro-pores.
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http://dx.doi.org/10.1111/nph.17857 | DOI Listing |
Mult Scler Relat Disord
September 2025
Department of Psychology, Wayne State University, Detroit, MI, 48202, USA; Institute of Gerontology, Wayne State University, Detroit, MI, 48202, USA; Translational Neuroscience Program, Wayne State University, Detroit, MI, 48201, USA. Electronic address:
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View Article and Find Full Text PDFFood Chem
September 2025
Nantong Food and Drug Supervision and Inspection Center, Nantong 226001, PR China.
Different starch crystal structures significantly influence meat product quality, though their specific impacts on myofibrillar protein (MP) functionality remain unclear despite industry demand for optimized ingredients. This study compared how potato, corn, mung bean, and pea starches affect MP properties in minced pork. Our findings reveal that starch-protein interactions fundamentally regulate MP gel and emulsion properties through the following mechanisms: First, starch promotes protein aggregation by enhancing hydrophobic interactions and disulfide bond formation, affecting gel network crosslinking.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
College of Chemistry and Chemical Engineering, Instrumental Analysis Center of Qingdao University, Qingdao Application Technology Innovation Center of Photoelectric Biosensing for Clinical Diagnosis and Treatment, Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, Qing
Silk fibroin (SF)-based flexible electronic/photonic materials have gained great attention in wearable devices and soft sensors. However, it remains challenging to understand the molecular interaction mechanisms and subsequently fabricate SF-based flexible materials that exhibit fluorescence, humidity sensitivity, and conductivity properties. In this study, by incorporating lanthanide europium ion (Eu), the design and fabrication of a flexible, fluorescent, and conductive SF membrane was proposed.
View Article and Find Full Text PDFJ Chem Inf Model
September 2025
United States Environmental Protection Agency, Center for Computational Toxicology and Exposure, 109 TW Alexander Dr., Research Triangle Park, North Carolina 27711, United States.
To assess environmental fate, transport, and exposure for PFAS (per- and polyfluoroalkyl substances), predictive models are needed to fill experimental data gaps for physicochemical properties. In this work, quantitative structure-property relationship (QSPR) models for octanol-water partition coefficient, water solubility, vapor pressure, boiling point, melting point, and Henry's law constant are presented. Over 200,000 experimental property value records were extracted from publicly available data sources.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Department of Chemistry, Northwestern University Evanston, Illinois 60208, United States.
Per- and polyfluoroalkyl substances (PFASs) are environmentally persistent, bioaccumulative, and toxic chemicals that contaminate global drinking water resources. Their ubiquity and potential impact on human health motivate large-scale remediation. Conventional materials used to remove PFASs during drinking water production are functionally inefficient or energetically expensive, motivating the discovery of new materials and technologies.
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