Publications by authors named "James Weston"

Purpose: To describe a new surgical technique that combines four-point, flanged polypropylene scleral fixation with a hydrophobic intraocular lens (IOL).

Methods: Using the Envista MX60 and 6.0 polypropylene, scleral four-point fixation was achieved using a flanged-suture technique five times in a model eye and in a case series of eight patients, retrospectively reviewed.

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The reverse osmosis water treatment process is prone to fouling issues, prompting the exploration of various membrane modification techniques to address this challenge. The primary objective of this study was to develop a precise method for modifying the surface of reverse osmosis membranes to enhance their antifouling properties. The Langmuir-Blodgett technique was employed to transfer aminated graphene oxide films assembled at the air-liquid interface, under specific surface pressure conditions, to the polyamide surface with pre-activated carboxylic groups.

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Membrane technology plays a central role in advancing separation processes, particularly in water treatment. Covalent organic frameworks (COFs) have transformative potential in this field due to their adjustable structures and robustness. However, conventional COF membrane synthesis methods are often associated with challenges, such as time-consuming processes and limited control over surface properties.

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Wound healing is facilitated by neoangiogenesis, a complex process that is essential to tissue repair in response to injury. MicroRNAs are small, noncoding RNAs that can regulate the wound healing process including stimulation of impaired angiogenesis that is associated with type-2 diabetes (T2D). Expression of miR-409-3p was significantly increased in the nonhealing skin wounds of patients with T2D compared to the non-wounded normal skin, and in the skin of a murine model with T2D.

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A diatom-associated bacterium, designated as strain F10, was isolated from a pure culture of the pennate diatom A3 and has since been used to characterize molecular mechanisms of symbiosis between phytoplankton and bacteria, including interactions using diatom-derived azelaic acid. Its origin from a hypersaline environment, combined with its capacity for quorum sensing, biofilm formation, and potential for dimethylsulfoniopropionate methylation/cleavage, suggest it is within the family . Initial phylogenetic analysis of the 16S rRNA gene sequence placed this isolate within the genus, but recent genomic and phylogenomic analyses show strain F10 is a separate lineage diverging from the genus .

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Angiogenesis is critical for tissue repair following myocardial infarction (MI), which is exacerbated under insulin resistance or diabetes. MicroRNAs are regulators of angiogenesis. We examined the metabolic regulation of miR-409-3p in post-infarct angiogenesis.

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We report, for the first time, a technique to synthesize free-standing, one-atom thick 2D gold crystals (namely, goldene) and self-assembled 2D periodic arrays of goldene. High-resolution transmission electron microscopy (HRTEM) imaging of goldene revealed herringbone and honeycomb lattices, which are primarily gold surface features due to its reconstruction. Imaging of these surface-only features by a nonsurface characterization technique such as HRTEM is an unequivocal proof of the absence of three-dimensionality in goldene.

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Diatoms are a major group of microalgae that initiate biofouling by surface colonization of human-made underwater structures; however, the involved regulatory pathways remain uncharacterized. Here, we describe a protocol for identifying and validating regulatory genes involved in the morphology shift of the model diatom species during surface colonization. We also provide a workflow for characterizing biofouling transformants.

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Article Synopsis
  • Diatoms, a major group of ocean phytoplankton, can adapt to tough marine conditions through surface colonization, which also affects human-built underwater structures.
  • The study identifies 61 signaling genes in the diatom Phaeodactylum tricornutum that are crucial for this process, focusing on G-protein-coupled receptors (GPCRs).
  • Transforming P. tricornutum with specific GPCR genes enhances its resistance to UV light and promotes a protective morphology, providing insight into how these organisms colonize surfaces and potential targets for developing eco-friendly anti-biofouling solutions.
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Being capable of rapid and complete structure switching, the martensitic phase transitions in molecular crystals are thought to hold a tremendous potential as thermally driven organic actuators. However, the mechanical engineering parlance in the assessment of their performance is not immediately legible to the chemistry research community that starts to explore these materials, and the unavailability of performance indices has precluded molecular crystals from being considered in the device design process. Here, we demonstrate that an organic martensite, hexamethylbenzene, can be used to perform work that is comparable to that of most actuator classes.

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Chemiluminescence, a process of transduction of energy stored within chemical bonds of ground-state reactants into light via high-energy excited intermediates, is known in solution, but has remained undetected in macroscopic crystalline solids. By detecting thermally induced chemiluminescence from centimeter-size crystals of an organic peroxide here we demonstrate direct transduction of heat into light by thermochemiluminescence of bulk crystals. Heating of crystals of lophine hydroperoxide to ~115 °C results in detectable emission of blue-green light with maximum at 530 nm with low chemiluminescent quantum yield [(2.

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The thermosalient crystals of terephthalic acid are extraordinarily mechanically compliant and reversibly shape-shift between two forms with different crystal habits. While the transition of form II to form I is spontaneous, the transition of form I to form II is latent and can be triggered by applying local mechanical stress, whereby crystals leap several centimeters in air. This mechanosalient effect (mechanically stimulated motility) is due to sudden release of strain that has accrued in the crystal of form I, which is a metastable structure at ambient conditions.

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We report a fast and cost-effective strategy towards the preparation of superhydrophobic composites where a double-sided adhesive tape is paved with charcoal particles. The composites are mechanically robust, and resistant to strong chemical agents.

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Among scholarly researchers, the Utrecht Work Engagement Scale (UWES) is a popular scale for assessing employee or work engagement. However, challenges to the scale's validity have raised major concerns about the measurement and conceptualization of engagement as a construct. Across 4 field samples, we examined 2 measures of engagement, the UWES and the Job Engagement Scale (JES), in both factor structure and patterns of relationships with theoretically hypothesized antecedents and consequences.

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The Neural Crest, a transient epithelium in vertebrate embryos, is the source of putative stem cells known to give rise to neuronal, glial and endocrine components of the peripheral (sensory, autonomic and enteric) nervous system (PNS) and pigment cells in the skin. The Neural Crest is also widely believed to be the source of mesectodermal derivatives (skeletogenic, odontogenic, connective tissue and smooth muscle mesenchyme) in the vertebrate head [see (Bronner and LeDouarin, 2012; Le Douarin, 2012; Le Douarin and Kalcheim, 1999); see also (Hörstadius, 1950; Weston, 1970)]. This conventional understanding of the broad developmental potential of the Neural Crest has been challenged over the past few years (Breau et al.

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We report a versatile method for the fabrication of nanowires and hierarchical porous materials from a wide variety of ceramic materials such as CaCO3, ZnO, CuO, Co3O4, Co-doped ZnO, and Ag2O. The method consists of evaporation of CO2-enriched water microdroplets (diameter ∼3 μm) deposited from an aerosol onto heated substrates (T = 120 °C). A variety of porous scaffolds with 1-3 μm sized pores can be generated by tuning the process conditions.

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The neural crest is a transient structure unique to vertebrate embryos that gives rise to multiple lineages along the rostrocaudal axis. In cranial regions, neural crest cells are thought to differentiate into chondrocytes, osteocytes, pericytes and stromal cells, which are collectively termed ectomesenchyme derivatives, as well as pigment and neuronal derivatives. There is still no consensus as to whether the neural crest can be classified as a homogenous multipotent population of cells.

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Hurricanes are relatively frequent ecological disturbances that may cause potentially long-term impacts to the coastal environment. Hurricane Katrina hit the Mississippi Gulf Coast in August 2005, and caused a storm surge with the potential to change the trace element content of coastal surface sediments. In this study, surface estuarine and marine sediments were collected monthly following the storm from ten sites along the Mississippi Gulf Coast (Mobile Bay, Grand Bay Bayous Heron and Cumbest, Pascagoula, Ocean Springs, Biloxi Gulf, Back Biloxi Bay, Gulfport Gulf, Gulfport Courthouse Rd, and Gulfport Marina).

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The goal of the present study was twofold: to rapidly assess the potential environmental toxicological response following the storm surge and flooding caused by Hurricane Katrina along the Gulf Coast of Mississippi, USA, in August 2005, and to establish post-Katrina baseline toxicological profiles for three environmental matrices (water, suspended sediments, and sediments) within the intertidal zone. Sediment and water samples were collected monthly from September 2005 to 2006 from 10 sites along the Gulf Coast from Gulfport, Mississippi, to Mobile Bay, Alabama. Water samples and suspended sediment matrices were extracted, assayed, and toxic equivalent values calculated for compounds with estrogenic potential, using the yeast estrogen screen, and CYP1A induction potential, using the H4IIE rat hepatoma ethoxyresorufin-O-deethylase assay.

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For the first time, the existence of a substrate adduct of a nickel superoxide dismutase (NiSOD) model, based on the first nine residues from the N terminus of the active form of Streptomyces coelicolor NiSOD, has been proven and the adduct has been isolated. This adduct is based on the cyanide anion (CN(-)), as a substrate analogue of the superoxide anion (O(2)(*-)), and the nickel metallopeptide H-HCDLPCGVY-NH(2)-Ni. Spectroscopic studies, including IR, UV/Vis, and liquid- and solid-state NMR spectroscopy, show a single nickel-bound cyanide anion, which is embedded in the metallopeptide structure.

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The nickel complex of a synthetic nonapeptide (HCDLPCFVY-NH2) is capable of catalytically disproportionating O2(.-) and is thus a functional biomimetic for nickel superoxide dismutases. This represents a simplification as compared to a NiSOD "maquette" that is based on a dodecapeptide that was recently reported [Inorg.

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The neural crest is generally believed to be the embryonic source of skeletogenic mesenchyme (ectomesenchyme) in the vertebrate head and other derivatives, including pigment cells and neurons and glia of the peripheral nervous system. Although classical transplantation experiments leading to this conclusion assumed that embryonic neural folds were homogeneous epithelia, we reported that embryonic cranial neural folds contain spatially and phenotypically distinct domains, including a lateral nonneural domain with cells that coexpress E-cadherin and PDGFRalpha and a thickened mediodorsal neuroepithelial domain where these proteins are reduced or absent. We now show that Wnt1-Cre is expressed in the lateral nonneural epithelium of rostral neural folds and that cells coexpressing Cre-recombinase and PDGFRalpha delaminate precociously from some of this nonneural epithelium.

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Amchitka Island (51degrees N lat, 179 degrees E long) was the site of three underground nuclear tests from 1965-1971. There have been no substantive studies of radionuclides in marine fishes and birds in the area since the mid-1970's. In this study, levels of 60Co, 52Eu, 90Sr, 99Tc, 129I, 137Cs, and the actinides (241Am, 238Pu, 239,240Pu, 234U, 235U, 236U, and 238U) were studied in ten marine fish species (including Pacific Cod Gadus macrocephalus and Pacific Halibut Hippoglossus stenolepis) and five marine bird species (including Glaucous-winged Gulls Larus glaucescens, Tufted Puffins Fratercula cirrhata, and Common Eider Ducks Somateria mollissima) from Amchitka.

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Recreational and subsistence fishing plays a major role in the lives of many people, although most Americans obtain their fish from supermarkets or other commercial sources. Fish consumption has generally increased in recent years, largely because of the nutritional benefits. Recent concerns about contaminants in fish have prompted federal and state agencies to analyze fish (especially freshwater fish targeted by recreational anglers) for contaminants, such as mercury and polychlorinated biphenyls (PCBs), and to issue fish consumption advisories to help reduce the public health risks, where warranted.

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The occurrence of environmental pharmaceutical products has recently received considerable attention, but impacts on the aquatic environment are largely unknown. Fluoxetine is a widely prescribed antidepressant and acts physiologically as a selective serotonin reuptake inhibitor (SSRI). To determine its potential to disrupt teleost reproductive function, Japanese medaka (Oryzias latipes) were exposed to fluoxetine at aqueous nominal concentrations of 0, 0.

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