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On the use of consistent bias corrections to enhance the impact of Aeolus Level-2B Rayleigh winds on National Oceanic and Atmospheric Administration global forecast skill
(Wiley, 2023-10-14) Liu, Hui; Garrett, Kevin; Ide, Kayo; Hoffman, Ross N.
The operational Aeolus Level-2B (L2B) horizontal line-of-sight (HLOS) retrieved Rayleigh winds, produced by the European Space Agency (ESA), utilize European Centre for Medium-Range Weather Forecasts (ECMWF) short-term forecasts of temperature, pressure, and horizontal winds in the Rayleigh–Brillouin and M1 correction procedures. These model fields or backgrounds can contain ECMWF model-specific errors, which may propagate to the retrieved Rayleigh winds. This study examines the sensitivity of the retrieved Rayleigh winds to the changes in the model backgrounds, and the potential benefit of using the same system, in this case the National Oceanic and Atmospheric Administration's Finite-Volume Cubed Sphere Global Forecast System (FV3GFS), for both the corrections and the data assimilation and forecast procedures. It is shown that the differences in the model backgrounds (FV3GFS minus ECMWF) can propagate through the Level-2B horizontal line-of-sight Rayleigh wind retrieval process, mainly the M1 correction, resulting in differences in the retrieved Rayleigh winds with mean and standard deviation of magnitude as large as 0.2 m·s−1. The differences reach up to 0.4, 0.6, and 0.7 m·s−1 for the 95th, 99th, and 99.5th percentiles of the sample distribution with maxima of ∼1.4 m·s−1. The numbers of the large differences for the combined lower and upper 5th, 1st, and 0.5th percentile pairs are ∼6,100, 1,220, and 610 between 2.5 and 25 km height globally per day respectively. The ESA-disseminated Rayleigh wind product (based on the ECMWF corrections) already shows a significant positive impact on the FV3GFS global forecasts. In the observing system experiments performed, compared with the ESA Rayleigh winds, the use of the FV3GFS-corrected Rayleigh winds lead to ∼0.5% more Rayleigh winds assimilated in the lower troposphere and show enhanced positive impact on FV3GFS forecasts at the day 1–10 range but limited to the Southern Hemisphere.
Fermenting kale (Brassica oleracea L.) enhances its functional food properties by increasing accessibility of key phytochemicals and reducing antinutritional factors
(Wiley, 2024-05-06) Subedi, Ujjwol; Raychaudhuri, Samnhita; Fan, Si; Ogedengbe, Opeyemi; Obanda, Diana N.
The properties of kale as a functional food are well established. We sought to determine how fermentation further enhances these properties. We tested different fermentation conditions: (i) spontaneous fermentation with naturally occurring bacteria, (ii) spontaneous fermentation with 2% salt, (iii) Lactococcus lactis, (iv) Lactobacillus acidophilus, (v) mixture of L. lactis and L. acidophilus, (vi) mixture of L. lactis, L. acidophilus, and Clostridium butyricum. We quantified selected bioactive components using high-performance liquid chromatography (HPLC) and antinutritional factors using a gravimetric method and spectrophotometry. We then determined (i) the antioxidant capacity of the vegetable, (ii) anti-inflammation capacity, and (iii) the surface microbiota composition by 16S sequencing. All fermentation methods imparted some benefits. However, fermentation with mixed culture of L. lactis and L. acidophilus was most effective in increasing polyphenols and sulforaphane accessibility, increasing antioxidant activity, and reducing antinutritional factors. Specifically, fermentation with L. lactis and L. acidophilus increased total polyphenols from 8.5 to 10.7 mgGAE/g (milligrams of gallium acid equivalent per gram) and sulforaphane from 960.8 to 1777 μg/g (microgram per gram) but decreased the antinutritional factors oxalate and tannin. Total oxalate was reduced by 49%, while tannin was reduced by 55%–65%. The antioxidant capacity was enhanced but not the anti-inflammation potential. Both unfermented and fermented kale protected equally against lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages and prevented increases in inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 messenger RNA (IL-6 mRNA) expression by 84.3%, 62%, 68%, and 85.5%, respectively. Unfermented and naturally fermented kale had high proportions of sulfur reducing Desulfubrio and Proteobacteria usually associated with inflammation. Fermenting with L. lactis and/or L. acidophilus changed the bacterial proportions, reducing the Proteobacteria while increasing the genera Lactobacilli and Lactococcus. In summary, fermentation enhances the well-known beneficial impacts of kale. Fermentation with mixed cultures of L. lactis and L. acidophilus imparts higher benefits compared to the single cultures or fermentation with native bacteria present in the vegetable.
Computational fluid dynamics-based design and in vitro characterization of a novel pediatric pump-lung
(Wiley, 2023-10-05) Han, Dong; Zhang, Jiafeng; He, Ge; Griffith, Bradley P.; Wu, Zhongjun J.
Background
Although extracorporeal membrane oxygenation (ECMO) has been used to provide temporary support for pediatric patients suffering severe respiratory or cardiac failure since 1970, ECMO systems specifically designed for pediatric patients, particularly for long-term use, remain an unmet clinical need. We sought to develop a new pediatric ECMO system, that is, pediatric pump-lung (PPL), consisting of a unique cylinder oxygenator with an outside-in radial flow path and a centrifugal pump.
Methods
Computational fluid dynamics was used to analyze the blood fluid field for optimized biocompatible and gas exchange performances in terms of flow characteristics, hemolysis, and gas transfer efficiency. Ovine blood was used for in vitro hemolysis and gas transfer testing.
Results
Both the computational and experimental data showed that the pressure drop through the PPL's oxygenator is significantly low, even at a flow rate of more than 3.5 L/min. The PPL showed better hemolysis performance than a commercial ECMO circuit consisting of the Quadrox-iD pediatric oxygenator and the Rotaflow pump at a 3.5 L/min flow rate and 250 mm Hg afterload pressure. The oxygen transfer rate of the PPL can reach over 200 mL/min at a flow rate of 3.5 L/min.
Conclusions
The PPL has the potential to provide adequate blood pumping and excellent respiratory support with minimal risk of hemolysis for a wide range of pediatric patients.
Design and Assembly of Block Copolymer-Modified Nanoparticles into Supracolloidal, Molecular Mimics
(2023) Webb, Kyle; Fourkas, John T; Nie, Zhihong; Chemistry; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
Large strides have been achieved in nanoparticle self-assembly, using various strategies to achieve ordered, supracolloidal structures, ranging from dimers to chains and vesicles to 3-D lattices. However, these methods, while expanding the scope and accessibility of design, face inherent limitations in targeting complex structures with high yields, particularly when using isotropic building blocks (e.g. gold nanoparticles and polystyrene nanoparticles). Additionally, research studying the reversibility of nanoparticle assemblies is mostly limited to small-ligand-modified particles rather than polymer-modified nanoparticles. Polymers are particularly advantageous as they provide a higher degree of functionality to the nanoparticle surface and allow for increased control in directing particle interactions. This control is necessary to continue furthering the advancement of gold nanoparticles in plasmonics, sensors, and catalysts. Here, we introduce two strategies to assemble gold nanoparticles into supracolloidal nanostructures. Gold nanoparticles are modified with complementary, functionalized-block-copolymers that drive the assembly of the nanoparticles. The first strategy uses a diblock copolymer composed of a hydrophilic outer block and an acid or base-functionalized inner block. Upon mixing, particles are assembled due to the acid–base neutralization between the complementary block copolymers. The resultant supracolloids consist of nanoparticles precisely arranged in space, which mimic the geometries of small molecules. The particle interactions are fine tuned by varying the size and feeding ratio of the nanoparticles, along with the length and composition of the block copolymers. Careful tuning of these parameters yields nanostructures with different valences that were produced in high yield. Additionally, the implementation of a long outer, hydrophilic polymer block provided the assembled nanostructures stability when transferred from THF to water. Colloidal stability in an aqueous medium could allow for expanded use of these nanostructures in cellular uptake studies and biomedical applications.
The second strategy uses a diblock copolymer composed of a hydrophilic outer block and an inner block containing either complementary host or guest moieties. Particularly, we take advantage of the well-established interactions between β-cyclodextrin and adamantane as the host and guest molecules. Upon the slow addition of water, particles assemble due to the host–guest interactions between the complementary block copolymers, as the hydrophobic adamantane moieties are driven within the β-cyclodextrin macrocycles. Fine tuning of the nanoparticle sizes and feeding ratios and the block copolymer lengths and compositions results in high yields of targeted supracolloids that also mimic the geometries of molecules. Interestingly, the size difference between the host and guest-modified particles led to different types of nanostructures.
In addition, due to the reversibility of the host–guest interactions, we demonstrate the ability of our system to reorder in response to competitive host moieties. Upon addition of free β-cyclodextrin, the host–guest interactions are disrupted, resulting in disassembly of the nanostructures, which we could reassemble upon removal of the free cyclodextrin. Finally, due to the strength of the nanoparticle interactions, we also tested the selectivity of the nanoparticle interactions by assembling the host building block with different guest building blocks. We showed that when assembled with competing guest building blocks, the β-cyclodextrin building blocks preferentially interact the adamantane building blocks due to the stronger particle interactions. This reversibility and selectivity make our system a potential candidate for use in biosensors.
Testing the Limits: A DC Ecoblock Creates Community for Everyone
(2019) Rowedder, Patricia; Gabrielli, Julie; Architecture; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
Loneliness is an emotional feeling that represents disconnection. With one in
five people suffering from loneliness, it has become a public health crisis. Ranked
second in the nation for loneliness, Washington DC is three times the national
average. The transient nature of the greater DC population has created a negative
perception on the city, causing people to either move on or move out. Such a
progressive and influential city seems stuck in a stagnant pattern, not reacting to the
constantly changing density, mobility, and needs of the built and non-built
environment.
This thesis aims to explore the connections of ecology and psychology of
architecture through a superblock typology in an effort to battle loneliness in the
nation’s capital. A superblock is a large-scale entity both extroverted and permeable
composed of business, community, and other institutional programs, each different
but overlapping in a common elements and connections.
The superblock throughout time has been given a negative connotation
because of exploited failed attempts. When using the principles correctly, however,
the superblock typology provides endless possibilities and solutions to connect,
engage, and ignite community interaction through strategically placed nodes of space
and diverse program.
If one were to take create new principle site, culture, and health specific,
could a meaningful interaction and connection through a ecoblock in DC be created?