Examining the Effects of pH and Macrophyte Diversity on Benthic Macroinvertebrate Assemblages in Adirondack Lakes

Acidification in ecosystems, such as water bodies of the northeastern United States, causes significant changes in their biological communities. Changes in lower trophic levels significantly affect the structure and function of higher trophic levels. Benthic macroinvertebrates are useful when examining the effects of acidification because different species are tolerant or sensitive to particular conditions and can act as indicators of water quality. Macrophyte diversity is another explanatory variable influencing macroinvertebrates. Many studies have examined macroinvertebrate assemblages in streams related to water quality, but macroinvertebrates in lakes are less well studied. We compared the benthic macroinvertebrate assemblages in four Adirondack lakes with differing pH. We predicted that as pH decreased, the abundance and diversity of the macroinvertebrates would decline. To test this, we measured pH and collected 40 benthic samples from four Adirondack lakes using a PONAR samler. Macroinvertebrates were sorted, identified to the lowest possible taxon (generally family or genus) and tallied. Macrophytes were identified and diversity was estimated with the Shannon Diversity Index. Benthic macroinvertebrate richness decreased with lower pH (p = 0.03) and increased with greater macrophyte diversity (p =0.02). However, total macroinvertebrate abundance was not statistically correlated with pH (p = 0.08) or macrophyte diversity (p = 0.07). Diversity is often considered a strong indicator of ecosystem health, thus our results suggest that further reduction of acidification may restore diversity of lower trophic levels in Adirondack lakes and improve their ecological conditions

Electrical challenges of heteroepitaxial 3C-SiC on silicon

© 2018 Trans Tech Publications, Switzerland. We have investigated the electrical conduction in epitaxial cubic silicon carbide films on low-doped and high-resistive silicon substrates. The electrical properties of the film/substrate system such as the carrier concentration, carrier mobility, and sheet resistance were evaluated by performing Hall measurements in a van der Pauw configuration at room temperature. For the SiC on low-doped p-Si, we found that the charge carriers in the substrate always dominate the electrical conduction indicating an electrical shorting of the film to the substrate and the absence of a p/n junction. Meanwhile, for the SiC films grown on high-resistive silicon, we found an evidence of current leakage through a silicon region right below the SiC/Si interface, generated upon SiC growth. Leakage resistances in the kΩ range obtained from TLM structures made of isolated SiC pillars on high-resistive silicon confirmed the presence of a conductive region below the SiC/Si interface. This work also shows that this electrical leakage can be supressed using a high-resistive silicon as the substrate and etching away the conductive region below the interface

Improving the Synthesis of an Unnatural Fluorescent Amino Acid

The long-term goal of this project is to more efficiently synthesize an unnatural fluorescent amino acid, 3-[7-nitro-2,1,3-benzoxadiazol-4-yl]-L-alanine, diazole for short. This fluorescent amino acid can be incorporated into a transparent protein, thus creating a “glow-in-the-dark” protein. Two parallel pathways are being explored to synthesize this diazole amino acid: traditional organic synthesis and biocatalysis. 1H-NMR and LC-MS are being used to analyze the organic route by monitoring the reaction kinetics of the key coupling reaction. The goal of these kinetics experiments is to identify optimal reaction conditions (solvent, temperature, etc.). For the biocatalytic route, the enzyme glutathione S-transferase from the cyanobacterium T. elongatus is being used to catalyze the key coupling reaction. Enzyme kinetics are monitored using LC-MS

New light on the ‘Drummer of Tedworth’: conflicting narratives of witchcraft in Restoration England

This paper presents a definitive text of hitherto little-known early documents concerning ‘The Drummer of Tedworth’, a poltergeist case that occurred in 1662-3 and became famous not least due to its promotion by Joseph Glanvill in his demonological work, Saducismus Triumphatus. On the basis of these and other sources, it is shown how responses to the events at Tedworth evolved from anxious piety on the part of their victim, John Mompesson, to confident apologetic by Glanvill, before they were further affected by the emergence of articulate scepticism about the case

Who is a compatible partner for a male mouse?

The complex issue of social housing of laboratory mice was addressed by studying the housing compatibility of male mice with castrated males, or with ovariectomized females, for a period of up to seven weeks. Sexually mature males were shown to be socially incompatible with castrated males of the same age but to be more compatible with same age or older ovariectomized females (results varied according to the mouse strains used). These ovariectomized females could also be repeatedly housed with different sets of younger male mice, even after being briefly separated and again re-paired. Our data suggest that ovariectomized females could be used to establish a long-term companion group fully compatible for male mice group housing

Electrical leakage phenomenon in heteroepitaxial cubic silicon carbide on silicon

© 2018 Author(s). Heteroepitaxial 3C-SiC films on silicon substrates are of technological interest as enablers to integrate the excellent electrical, electronic, mechanical, thermal, and epitaxial properties of bulk silicon carbide into well-established silicon technologies. One critical bottleneck of this integration is the establishment of a stable and reliable electronic junction at the heteroepitaxial interface of the n-type SiC with the silicon substrate. We have thus investigated in detail the electrical and transport properties of heteroepitaxial cubic silicon carbide films grown via different methods on low-doped and high-resistivity silicon substrates by using van der Pauw Hall and transfer length measurements as test vehicles. We have found that Si and C intermixing upon or after growth, particularly by the diffusion of carbon into the silicon matrix, creates extensive interstitial carbon traps and hampers the formation of a stable rectifying or insulating junction at the SiC/Si interface. Although a reliable p-n junction may not be realistic in the SiC/Si system, we can achieve, from a point of view of the electrical isolation of in-plane SiC structures, leakage suppression through the substrate by using a high-resistivity silicon substrate coupled with deep recess etching in between the SiC structures

A Networks-Science Investigation into the Epic Poems of Ossian

In 1760 James Macpherson published the first volume of a series of epic poems which he claimed to have translated into English from ancient Scottish-Gaelic sources. The poems, which purported to have been composed by a third-century bard named Ossian, quickly achieved wide international acclaim. They invited comparisons with major works of the epic tradition, including Homer's Iliad and Odyssey, and effected a profound influence on the emergent Romantic period in literature and the arts. However, the work also provoked one of the most famous literary controversies of all time, colouring the reception of the poetry to this day. The authenticity of the poems was questioned by some scholars, while others protested that they misappropriated material from Irish mythological sources. Recent years have seen a growing critical interest in Ossian, initiated by revisionist and counter-revisionist scholarship and by the two-hundred-and-fiftieth anniversary of the first collected edition of the poems in 1765. Here we investigate Ossian from a networks-science point of view. We compare the connectivity structures underlying the societies described in the Ossianic narratives with those of ancient Greek and Irish sources. Despite attempts, from the outset, to position Ossian alongside the Homeric epics and to distance it from Irish sources, our results indicate significant network-structural differences between Macpherson's text and those of Homer. They also show a strong similarity between Ossianic networks and those of the narratives known as Acallam na Sen\'orach (Colloquy of the Ancients) from the Fenian Cycle of Irish mythology.Comment: Accepted for publication in Advances in Complex system