Broadband choke for antenna structure

Broadband chokes and absorbers to reduce spurious radiation patterns of antenna array caused by support structure

Of Wilderness, Forest, and Garden: An Eco-Theory of Genre in Middle English Literature

“Of Wilderness, Forest, and Garden: An Eco-Theory of Genre in Middle English Literature” proposes a new theory of genre that considers the material elements of the natural environment in Middle English literature composed between 1300-1450 CE. Instead of treating the setting as just a backdrop for human activity, I posit that the components of the environment play a role in the deployment of the narrative by shaping the characters and influencing the action. More than an acknowledgement of the particular natural features, this study explores the role that these components play and how they give us a deeper understanding of the text. This project presents a view of the text that both engages and augments the traditional genre classification, offering a way to study a lesser considered subject in medieval literature—the material world of the setting—by reassessing the genre classification of the texts. By teasing out the material details of the setting, an eco-theory of genre cuts across conventional genres and offers another way to connect medieval texts. I argue that, instead of romance, Breton Lai, ballad, and fabliau, the texts examined in this dissertation are wilderness, forest, or garden poems. The eco-theory of the genre wilderness sees the adversarial elements in an untamed environment. The forest genre is a space of rules and regulations that circumscribe the environment and, in turn, manage the resources found there. The genre of the garden focuses on the conflict between what is manmade and what is natural and considers which of these is more real. By thoroughly investigating the representations of material nature within certain Middle English texts, such as Sir Gawain and the Green Knight, The Geste of Robyn Hode, and “The Franklin’s Tale” from The Canterbury Tales, it is the aim of this dissertation to demonstrate that medieval people negotiated the divide between the philosophy of nature and the lived experience of nature through literature

True to oneself? Broad and narrow ideas on authenticity in the enhancement debate

Our knowledge of the human brain and the influence of pharmacological substances on human mental functioning is expanding. This creates new possibilities to enhance personality and character traits. Psychopharmacological enhancers, as well as other enhancement technologies, raise moral questions concerning the boundary between clinical therapy and enhancement, risks and safety, coercion and justice. Other moral questions include the meaning and value of identity and authenticity, the role of happiness for a good life, or the perceived threats to humanity. Identity and authenticity are central in the debate on psychopharmacological enhancers. In this paper, I first describe the concerns at issue here as extensively propounded by Carl Elliott. Next, I address David DeGrazia’s theory, which holds that there are no fundamental identity-related and authenticity-related arguments against enhancement technologies. I argue, however, that DeGrazia’s line of reasoning does not succeed in settling these concerns. His conception of identity does not seem able to account for the importance we attach to personal identity in␣cases where personal identity is changed through enhancement technology. Moreover, his conception of authenticity does not explain the reason why we find inauthentic values objectionable. A broader approach to authenticity can make sense of concerns about changes in personal identity by means of enhancement technologies

Verifying timestamps of occultation observation systems

We describe an image timestamp verification system to determine the exposure timing characteristics and continuity of images made by an imaging camera and recorder, with reference to Coordinated Universal Time (UTC). The original use was to verify the timestamps of stellar occultation recording systems, but the system is applicable to lunar flashes, planetary transits, sprite recording, or any area where reliable timestamps are required. The system offers good temporal resolution (down to 2 msec, referred to UTC) and provides exposure duration and interframe dead time information. The system uses inexpensive, off-the- shelf components, requires minimal assembly and requires no high-voltage components or connections. We also describe an application to load FITS (and other format) image files, which can decode the verification image timestamp. Source code, wiring diagrams and built applications are provided to aid the construction and use of the device.Comment: 10 pages, 7 figures, accepted to Publications of the Astronomical Society of Australia (PASA

Archaeal Hel308 helicase targets replication forks in vivo and in vitro and unwinds lagging strands

Mutations in mammalian and Drosophila Hel308 and PolQ paralogues cause genome instability but their helicase functions are mysterious. By in vivo and in vitro analysis, we show that Hel308 from archaea (Hel308a) may act at stalled replication forks. Introducing hel308a into Escherichia coli dnaE strains that conditionally accumulate stalled forks caused synthetic lethality, an effect indistinguishable from E.coli RecQ. Further analysis in vivo indicated that the effect of hel308a is exerted independently of homologous recombination. The minimal biochemical properties of Hel308a protein were the same as human Hel308. We describe how helicase actions of Hel308a at fork structures lead specifically to displacement of lagging strands. The invading strand of D-loops is also targeted. Using archaeal Hel308, we propose models of action for the helicase domain of PolQ, promoting loading of the translesion polymerase domain. We speculate that removal of lagging strands at stalled forks by Hel308 promotes the formation of initiation zones, priming restart of lagging strand synthesis

The Lehmann discontinuity

Recent reflections by Inge Lehmann on her discovery of the inner core (Eos, January 20, 1987, p. 33; see also Bolt [1987, 1982]) remind us that this outstanding Earth scientist is now in her 100th year. The inner core boundary (ICB) is one of the three great seismic-compositional discontinuities that divide Earth into crust, mantle, core, and inner core. The other two discontinuities are well known by names honoring their discoverers, Andrija Mohorovicic and Beno Gutenberg. In this tradition, it is fitting that the ICB be called the Lehmann Discontinuity in honor of its discoverer

The Associations Between Self-Reported Exposure to the Chernobyl Nuclear Disaster Zone and Mental Health Disorders in Ukraine

In 1986, Reactor 4 of the Chernobyl nuclear power plant near Pripyat, Ukraine exploded, releasing highly-radioactive materials into the surrounding environment. Although the physical effects of the disaster have been well-documented, a limited amount of research has been conducted on association of the disaster with long-term, clinically-diagnosable mental health disorders. According to the diathesis–stress model, the stress of potential and unknown exposure to radioactive materials and the ensuing changes to ones life or environment due to the disaster might lead those with previous vulnerabilities to fall into a poor state of mental health. Previous studies of this disaster have found elevated symptoms of stress, substance abuse, anxiety, and depression in exposed populations, though often at a subclinical level.Materials and methodsWith data from The World Mental Health Composite International Diagnostic Interview, a cross-sectional large mental health survey conducted in Ukraine by the World Health Organization, the mental health of Ukrainians was modeled with multivariable logistic regression techniques to determine if any long-term mental health disorders were association with reporting having lived in the zone affected by the Chernobyl nuclear disaster. Common classes of psychiatric disorders were examined as well as self-report ratings of physical and mental health.ResultsReporting that one lived in the Chernobyl-affected disaster zone was associated with a higher rate of alcohol disorders among men and higher rates of intermittent explosive disorders among women in a prevalence model. Subjects who lived in the disaster zone also had lower ratings of personal physical and mental health when compared to controls. DiscussionStress resulting from disaster exposure, whether or not such exposure actually occurred or was merely feared, and ensuing changes in life circumstances is associated with increased rates of mental health disorders. Professionals assisting populations that are coping with the consequences of disaster should be aware of possible increases in psychiatric disorders as well as poorer perceptions regarding personal physical and mental health

VIGILANCE OF NESTING WHOOPING CRANES IN JUNEAU COUNTY, WISCONSIN

Vigilance plays an important role in the detection of possible threats and reducing the risk of predation, including during the incubation period. We examined the visual vigilance of incubating whooping cranes (Grus americana) in Juneau County, Wisconsin, during the 2019 nesting season. We deployed 9 trail cameras and tagged crane presence and behavior in 32,801 photos which were used in our analysis. We assessed individual nest and environmental variables and their effects on vigilant behavior of incubating cranes using linear mixed-models. Vigilant behavior was defined by a posture in which the crane’s head was up, neck was erect, and bill was horizontal to the ground. Nesting whooping cranes were less vigilant during the night (x̄ = 14.3 ± 1.4% [SE]) than during the day (25.0 ± 0.7%), and cranes were less vigilant during precipitation events. Cranes nesting closer to closed forest were 11-12% less vigilant than those nesting at medium or far distances from forest. Lastly, cranes nesting in medium-sized wetlands were 4-5% more vigilant than cranes in small or large wetlands. Further research to determine if levels of vigilance affect nest success could help increase productivity for this population

Multilocus sequence types of invasive Corynebacterium diphtheriae isolated in the Rio de Janeiro urban area, Brazil

Invasive infections caused by Corynebacterium diphtheriae in vaccinated and non-vaccinated individuals have been reported increasingly. In this study we used multilocus sequence typing (MLST) to study genetic relationships between six invasive strains of this bacterium isolated solely in the urban area of Rio de Janeiro, Brazil, during a 10-year period. Of note, all the strains rendered negative results in PCR reactions for the tox gene, and four strains presented an atypical sucrose-fermenting ability. Five strains represented new sequence types. MLST results did not support the hypothesis that invasive (sucrose-positive) strains of C. diphtheriae are part of a single clonal complex. Instead, one of the main findings of the study was that such strains can be normally found in clonal complexes with strains related to non-invasive disease. Comparative analyses with C. diphtheriae isolated in different countries provided further information on the geographical circulation of some sequence types

Ions modulate stress-induced nano-texture in supported fluid lipid bilayers

Most plasma membranes comprise a large number of different molecules including lipids and proteins. In the standard fluid mosaic model, the membrane function is effected by proteins whereas lipids are largely passive and serve solely in the membrane cohesion. Here we show, using supported 1,2-dioleoyl-sn-glycero-3-phosphocholine lipid bilayers in different saline solutions, that ions can locally induce ordering of the lipid molecules within the otherwise fluid bilayer when the latter is supported. This nanoordering exhibits a characteristic length scale of ∼20 nm, and manifests itself clearly when mechanical stress is applied to the membrane. Atomic force microscopy (AFM) measurements in aqueous solutions containing NaCl, KCl, CaCl2, and Tris buffer show that the magnitude of the effect is strongly ion-specific, with Ca2+ and Tris, respectively, promoting and reducing stress-induced nanotexturing of the membrane. The AFM results are complemented by fluorescence recovery after photobleaching experiments, which reveal an inverse correlation between the tendency for molecular nanoordering and the diffusion coefficient within the bilayer. Control AFM experiments on other lipids and at different temperatures support the hypothesis that the nanotexturing is induced by reversible, localized gel-like solidification of the membrane. These results suggest that supported fluid phospholipid bilayers are not homogenous at the nanoscale, but specific ions are able to locally alter molecular organization and mobility, and spatially modulate the membrane’s properties on a length scale of ∼20 nm. To illustrate this point, AFM was used to follow the adsorption of the membrane-penetrating antimicrobial peptide Temporin L in different solutions. The results confirm that the peptides do not absorb randomly, but follow the ion-induced spatial modulation of the membrane. Our results suggest that ionic effects have a significant impact for passively modulating the local properties of biological membranes, when in contact with a support such as the cytoskeleton