Szego coordinates, quadrature domains, and double quadrature domains

We define Szego coordinates on a finitely connected smoothly bounded planar domain which effect a holomorphic change of coordinates on the domain that can be as close to the identity as desired and which convert the domain to a quadrature domain with respect to boundary arc length. When these Szego coordinates coincide with Bergman coordinates, the result is a double quadrature domain with respect to both area and arc length. We enumerate a host of interesting and useful properties that such double quadrature domains possess, and we show that such domains are in fact dense in the realm of bounded finitely connected domains with smooth boundaries.Comment: 19 page

Municipal Capacity to Respond to COVID-19: Implications for Improving Community Resilience in Maine

The authors of this article explore how 50 Maine municipalities communicated their response to COVID-19 in the earliest stages of the pandemic. The study answers two questions: (1) What information and resources did Maine municipalities communicate about COVID-19? and (2) What characterizes a more robust communication response? Analyzing digital communications from March through July 2020, the authors found almost all municipalities in our sample communicated basic information about altered town operations. Some towns provided more robust responses that evolved over time and included nuanced messages about COVID-19, a sense of community, and collaborations with partners. While smaller, more rural municipalities may have fewer residents and resources, many showed a larger-than-expected capacity to pivot quickly and rally together to respond to COVID-19 and communicate about that response

The histochemical assessment of sulpho-, sialo-, and neutral-mucosubstances in fetal gastric mucosa

Background: Mucins are complex composition of carbohydrates and may be present as a mixture of different types. Normal distribution of mucin and its alteration in various inflammatory, benign and malignant lesions of gastrointestinal tract has aroused interest in the field of histochemistry. The main purpose of present work is to study the staining pattern and distribution of cells in different parts of fetal gastric mucosa and to correlate the nature of gastric mucins and its functional significance.  Methods: A total of 25 fetus stomach specimens (total 75 samples) one sample each from different parts of the stomach like fundus, body and pylorus, from fresh specimens. The samples were washed in normal saline, fixed in 2% calcium acetate in 10% formalin. These tissues were routinely processed and paraffin blocks were prepared. 6 m sections of these blocks were taken for histological and different histochemical staining.Results: Fetal fundic part of stomach shows increased neutral mucin in surface epithelium and foveolar cells. With combined AB pH 2.5 - PAS technique increased neutral mucin and small amount of acid mucins are observed. With AB pH 1, surface epithelium and deep glands show negative staining. Moderate alcinophilia is observed in deep foveolar cells and glandular cells. AB pH 2.5 shows alcinophilia in surface epithelium, foveolar cells and mucous neck cells indicating presence of sialomucin. Fetal pyloric part of stomach shows increased acid and neutral mucins. With pH 2.5 - PAS staining, purple staining is observed in surface epithelium, deep foveolar and pyloric glands.  Conclusion: All types of mucosubstances - neutral, sialo and sulpho-mucins, are secreted in relatively increased amounts by the surface epithelium and the glands of the stomach of the human fetus and neonate. Sulphomucin is seen mainly in the cells of the surface epithelium.  

Time-series analysis of two hydrothermal plumes at 9°50′N East Pacific Rise reveals distinct, heterogeneous bacterial populations

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Geobiology 10 (2012): 178-192, doi:10.1111/j.1472-4669.2011.00315.xWe deployed sediment traps adjacent to two active hydrothermal vents at 9°50’N on the East Pacific Rise (EPR) to assess variability in bacterial community structure associated with plume particles on the time scale of weeks to months, to determine if an endemic population of plume microbes exists, and to establish ecological relationships between bacterial populations and vent chemistry. Automated rRNA intergenic spacer analysis (ARISA) indicated there are separate communities at the two different vents and temporal community variations between each vent. Correlation analysis between chemistry and microbiology indicated that shifts in the coarse particulate (>1 mm) Fe/(Fe+Mn+Al), Cu, V, Ca, Al, 232Th, and Ti as well as fine-grained particulate (<1 mm) Fe/(Fe+Mn+Al), Fe, Ca and Co are reflected in shifts in microbial populations. 16S rRNA clone libraries from each trap at three time points revealed a high percentage of Epsilonproteobacteria clones and hyperthermophilic Aquificae. There is a shift towards the end of the experiment to more Gammaproteobacteria and Alphaproteobacteria, many of whom likely participate in Fe and S cycling. The particle attached plume environment is genetically distinct from the surrounding seawater. While work to date in hydrothermal environments has focused on determining the microbial communities on hydrothermal chimneys and the basaltic lavas that form the surrounding seafloor, little comparable data exists on the plume environment that physically and chemically connects them. By employing sediment traps for a time series approach to sampling, we show that bacterial community composition on plume particles changes on time scales much shorter than previously known.This work was supported by the NSF Marine Geology and Geophysics program, the Science and Technology program, and the Gordon and Betty Moore Foundation

Distribution of extracellular flavins in a coastal marine basin and their relationship to redox gradients and microbial community members

The flavins (including flavin mononucleotide (FMN) and riboflavin (RF)) are a class of organic compounds synthesized by organisms to assist in critical redox reactions. While known to be secreted extracellularly by some species in laboratory-based cultures, flavin concentrations are largely unreported in the natural environment. Here, we present pore water and water column profiles of extracellular flavins (FMN and RF) and two degradation products (lumiflavin and lumichrome) from a coastal marine basin in the Southern California Bight alongside ancillary geochemical and 16S rRNA microbial community data. Flavins were detectable at picomolar concentrations in the water column (93–300 pM FMN, 14–40 pM RF) and low nanomolar concentrations in pore waters (250–2070 pM FMN, 11–210 pM RF). Elevated pore water flavin concentrations displayed an increasing trend with sediment depth and were significantly correlated with the total dissolved Fe (negative) and Mn (positive) concentrations. Network analysis revealed a positive relationship between flavins and the relative abundance of Dehalococcoidia and the MSBL9 clade of Planctomycetes, indicating possible secretion by members of these lineages. These results suggest that flavins are a common component of the so-called shared extracellular metabolite pool, especially in anoxic marine sediments where they exist at physiologically relevant concentrations for metal oxide reduction

Forest-core partitioning algorithm for speeding up analysis of water distribution systems

Abstract not availableAngus R. Simpson, Sylvan Elhay, Bradley Alexande