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Abstract Microbes are the drivers of soil phosphorus (P) cycling in terrestrial ecosystems; however, the role of soil microbes in mediating P cycling in P‐rich soils during primary succession remains uncertain. This study examined the impacts of bacterial community structure (diversity and composition) and its functional potential (absolute abundances of P‐cycling functional genes) on soil P cycling along a 130‐year glacial chronosequence on the eastern Tibetan Plateau. Bacterial community structure was a better predictor of soil P fractions than P‐cycling genes along the chronosequence. After glacier retreat, the solubilization of inorganic P and the mineralization of organic P were significantly enhanced by increased bacterial diversity, changed interspecific interactions, and abundant species involved in soil P mineralization, thereby increasing P availability. Although 84% of P‐cycling genes were associated with organic P mineralization, these genes were more closely associated with soil organic carbon than with organic P. Bacterial carbon demand probably determined soil P turnover, indicating the dominant role of organic matter decomposition processes in P‐rich alpine soils. Moreover, the significant decrease in the complexity of the bacterial co‐occurrence network and the taxa‐gene‐P network at the later stage indicates a declining dominance of the bacterial community in driving soil P cycling with succession. Our results reveal that bacteria with a complex community structure have a prominent potential for biogeochemical P cycling in P‐rich soils during the early stages of primary succession.
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Photonic Indistinguishability of the Tin-Vacancy Center in Diamond
Tin-vacancy centres in diamond are spin-photon interfaces with intrinsic environmental noise insensitivity. We reveal their high optical coherence in a nanostructured environment and generate single photons with a 99.7% purity and an indistinguishability of 63(9)%. [1]
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- Award ID(s):
- 1747426
- PAR ID:
- 10479851
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- ISBN:
- 978-1-957171-25-8
- Page Range / eLocation ID:
- SM1K.2
- Format(s):
- Medium: X
- Location:
- San Jose, CA
- Sponsoring Org:
- National Science Foundation
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Choosing your own adventure: Engaging the new learning society through integrative curriculum designIn our increasingly data-driven society, it is critical for high school students to learn to integrate computational thinking with other disciplines in solving real world problems. To address this need for the life sciences in particular, we have developed the Bio-CS Bridge, a modular computational system coupled with curriculum integrating biology and computer science. Our transdisciplinary team comprises university and high school faculty and students with expertise in biology, computer science, and education. Our approach engages students and teachers in scientific practices using biological data that they can collect themselves, and computational tools that they help to design and implement, to address the real-world problem of pollinator decline. Our modular approach to high school curriculum design provides teachers with the educational flexibility to address national and statewide biology and computer science standards for a wide range of learner types. We are using a teacher- leader model to disseminate the Bio-CS Bridge, whose components will be freely available online.more » « less
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BackgroundIncreasingly, college science courses are transitioning from a traditional lecture format to active learning because students learn more and fail less frequently when they engage in their learning through activities and discussions in class. Fear of negative evaluation (FNE), defined as a student’s sense of dread associated with being unfavorably evaluated while participating in a social situation, discourages undergraduates from participating in small group discussions, whole class discussions, and conversing one-on-one with instructors. ObjectiveThis study aims to evaluate the acceptability of a novel digital single-session intervention and to assess the feasibility of implementing it in a large enrollment college science course taught in an active learning way. MethodsTo equip undergraduates with skills to cope with FNE and bolster their confidence, clinical psychologists and biology education researchers developed Project Engage, a digital, self-guided single-session intervention for college students. It teaches students strategies for coping with FNE to bolster their confidence. Project Engage provides biologically informed psychoeducation, uses interactive elements for engagement, and helps generate a personalized action plan. We conducted a 2-armed randomized controlled trial to evaluate the acceptability and the preliminary effectiveness of Project Engage compared with an active control condition that provides information on available resources on the college campus. ResultsIn a study of 282 upper-level physiology students, participants randomized to complete Project Engage reported a greater increase in overall confidence in engaging in small group discussions (P=.01) and whole class discussions (P<.001), but not in one-on-one interactions with instructors (P=.05), from baseline to immediately after intervention outcomes, compared with participants in an active control condition. Project Engage received a good acceptability rating (1.22 on a scale of –2 to +2) and had a high completion rate (>97%). ConclusionsThis study provides a foundation for a freely available, easily accessible intervention to bolster student confidence for contributing in class. Trial RegistrationOSF Registries osf.io/4ca68 http://osf.io/4ca68more » « less
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Phosphorus (P) is critical for crop production but has a high nutrient use inefficiency. Tomato was grown in soil amended with five P-sources, used as-is, or embedded within a biodegradable polymer, polyhydroxyalkanoate (PHA). Correlation analysis identified treatments that maintain plant growth, improve bioavailable soil P, and reduce P loss. Three performance classes were identified: (i) micro- and nanohydroxyapatite, which did not increase bioavailable P, plant P-uptake, or change P in runoff/leaching compared to controls; (ii) monocalcium phosphate (MCP), dicalcium phosphate (DCP), calcium pyrophosphate nanoparticles (CAP), and PHA-MCP that increased P-uptake and/or bioavailable P but also increased P loss in runoff/leaching; and (iii) PHA-DCP and PHA-CAP, where increased bioavailable P and plant P-uptake were achieved with minimal P loss in runoff/leaching. In addition to identifying treatments that maintain plant growth, increase bioavailable P, and minimize nutrient loss, correlation plots also revealed that (i) bioavailable P was a good indicator of plant P-uptake; (ii) leached P could be predicted from water solubility; and (iii) P loss through runoff versus leaching showed similar trends. This study highlights that biopolymers can promote plant P-uptake and improve bioavailable soil P, with implications for mitigating the negative environmental impacts of P loss from agricultural systems.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/CLEO_SI.2023.SM1K.2
