The significance of the transport of nutrient-rich hypolimnetic water via the benthic boundary layer (BBL) to the productivity of Mono Lake was studied using a coupled hydrodynamic and ecological model validated against field data. The coupled model enabled us to differentiate between the role of biotic components and hydrodynamic forcing on the internal recycling of nutrients necessary to sustain primary productivity. A 4-year period (1991-1994) was simulated in which recycled nutrients from zooplankton excretion and bacterially-mediated mineralization exceeded sediment fluxes as the dominant source for primary productivity. Model outputs indicated that BBL transport was responsible for a 53% increase in the flux of hypolimnetic ammonium to the photic zone during stratification with an increase in primary production of 6% and secondary production of 5%. Although the estimated impact of BBL transport on the productivity of Mono Lake was not large, significant nutrient fluxes were simulated during periods when BBL transport was most active.
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http://dx.doi.org/10.1186/1746-1448-4-11 | DOI Listing |
Org Biomol Chem
January 2025
Catalysis Laboratory, School of Chemistry, University of Hyderabad, Hyderabad-500 046, India.
Simple and sustainable three- and four-step sequences of di-OH-protection/mono-OMe-deprotection/OrgRC and di-OH-protection/mono-OMe-deprotection/OrgRC/OMe-deprotection protocols were developed to construct biologically active natural products of irisoquin, irisoquin A, irisoquin D, irisoquin F, sorgoleone-364, embelin, rapanone, 5--methylembelin, 5--methylrapanone and their analogues from the commercially available 2,5-dihydroxy-1,4-benzoquinone, aliphatic aldehydes and Hantzsch ester (1,4-DHP) in very good to excellent yields by using organocatalytic reductive coupling (OrgRC) as key reaction. Many of these natural compounds exhibited a broad spectrum of biological activities including antioxidant, anti-inflammatory, anticonvulsant, anxiolytic, analgesic, anthelmintic, antitumor, antibacterial, and antifertility properties. At the same time, simple and readily available 2,5-dihydroxy-1,4-benzoquinone was transformed into a functionally rich library of 2,5-dihydroxy-3,6-dialkyl-1,4-benzoquinones in very good yields by using sequential OrgRC followed by deprotection reactions and resulting natural/unnatural products would be excellent targets for investigation to show their biological activities compared to known natural products.
View Article and Find Full Text PDFJ Opt Soc Am A Opt Image Sci Vis
August 2024
A topology optimization method is presented and applied to a blazed diffraction grating in reflection under conical incidence. This type of grating is meant to disperse the incident light on one particular diffraction order, and this property is fundamental in spectroscopy. Conventionally, a blazed metallic grating is made of a sawtooth profile designed to work with the ±1st diffraction order in reflection.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah, 84112, USA.
Fiber-reinforced composites (FRCs) possess a remarkable strength-to-weight ratio, making them ideal light-weighing alternative materials of metals used in automotive, aerospace, and outdoor equipment applications, but their recycling is challenging. Chemically recyclable thermoset polymers can enable fiber recovery and reuse; however, challenges remain in the separation and purification of depolymerized small molecules for efficient polymer recycling. To this end, a series of liquid resins for chemically recyclable polymer networks is designed based on phthalic anhydride, a widely produced and inexpensive chemical.
View Article and Find Full Text PDFSci Rep
January 2025
College of Engineering, Applied Science University (ASU), Manama, Kingdom of Bahrain.
This paper presents an in-depth analytical investigation into the time-dependent flow of a Casson hybrid nanofluid over a radially stretching sheet. The study introduces the effects of magnetic fields and thermal radiation, along with velocity and thermal slip, to model real-world systems for enhancing heat transfer in critical industrial applications. The hybrid nanofluid consists of three nanoparticles-Copper and Graphene Oxide-suspended in Kerosene Oil, selected for their stable and superior thermal properties.
View Article and Find Full Text PDFChembiochem
January 2025
Vilnius University: Vilniaus Universitetas, Life Sciences Center Institute of Biotechnology, Vilnius, LITHUANIA.
Enzyme functional analysis is a multifaceted process that can be used for various purposes, such as screening for specific activities, as well as developing, optimising, and validating processes or final products. Functional analysis methods are crucial for assessing enzyme performance and catalytic properties. Laccase, a well-known blue multi-copper oxidase, holds immense potential in diverse industries such as pharmaceuticals, paper and pulp, food and beverages, textiles, and biorefineries due to its clean oxidation process and versatility in handling a wide range of substrates.
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