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Тоонто Нютаг Homeland
No full textThis digital project explores and examines the declining language and culture of the Buryat people of Siberia, Russia.
For hundreds of years, the Buryat people were made up of independent tribes that lived nomadically in the Eastern Steppe. The colonialism of the Russian Empire and establishment of the Soviet Union introduced a century of cultural and linguistic oppression in Buryatia.
Utilizing interactive maps, timelines, and galleries, this project aims to answer the following questions: Who are the Buryat people, what has caused their language and culture to decline, and what action is being taken to preserve it
Synthesis of Dimeric Pyridinium Phenolate Dyes and Investigation of their Photophysical Properties
No full textSolvatochromic dyes have advanced the field of organic materials chemistry with their intriguing photophysical properties. They have applications as solvent polarity sensors as well as probes for studying solvent effects in supramolecular chemistry, chemical sensing, and examining biological processes. This study focuses on synthesising a range of bridged pyridinium based chromophores and investigating their photophysical behavior. This work aims to explore how solvatochromism and exciton coupling enhances the optical and electronic properties of these dyes. To do this, dimer 4,4\u27-((1,3-phenylenebis(methylene))bis(pyridine-1-ium-1,4-diyl))diphenolate (19), 4,4\u27-((1,2-phenylenebis(methylene))bis(pyridine-1-ium-1,4-diyl))diphenolate (21) and reference compound, 4-(1-benzylpyridin-1-ium-4-yl)phenolate (23) were synthesised in good yields using simple SN2 reaction. UV-vis spectroscopic analysis of these dyes was performed and compared against each other.
The absorption spectrum profiles revealed that dimer 19 and 21 exhibited an enhanced negative solvatochromism compared to monomer 23. It was also observed that bichromophoric 19 and 21 exhibited intense absorption with two peaks as a result of exciton coupling. The two chromophores interact intramolecularly, resulting in the splitting and an intense absorption band. This new findings will expand the applications of these dimeric phenolate dyes in the field of material organic chemistry
Single Amino Acid Changes Impact the Ability of Drosophila melanogaster Cecropins to Inhibit Growth of Providencia Pathogens
Full text linkAs antibiotic-resistant bacteria spread worldwide, the need to develop novel antimicrobial agents is urgent. One rich source of potential antimicrobials is the insect immune system, as insects produce a wide range of antimicrobial peptides (AMPs) with diverse sequences and structures. Insects also encounter many bacterial pathogens, some of which are closely related to pathogens of clinical relevance. However, despite interest in AMPs as therapeutics, the relationships between the amino acid sequence, biophysical properties, antimicrobial activity, and specificity are still not generalizable. To improve our understanding of these relationships, we assessed how single amino acid changes in cecropin AMPs produced by the fruit fly, Drosophila melanogaster, impact both their structure and their ability to inhibit the growth of Providencia species isolated from wild-caught D. melanogaster. These pathogens are of particular interest as they have a range of virulence in fruit flies, and work in vivo suggests that differences in virulence could be partially attributable to differential susceptibility to AMPs. D. melanogaster cecropins are 40 amino acids long but vary at only 5 residues with largely conservative changes. We found that these changes could impact inhibitory concentrations by up to 8-fold against Providencia species. Our investigation focused on a single amino acid position due to the importance of a flexible “hinge” in cecropin function. We found that altering the identity of this amino acid alone greatly impacted antimicrobial activity, changing bacterial susceptibility up to 16-fold. Generally, Providencia species that are less virulent in vivo are more susceptible to cecropin AMPs in vitro. We also observed differences in the kinetics of permeabilization and bacterial killing between species, suggesting that peptide-membrane interactions were differently affected by single amino acid changes and that bacteria in this genus may vary in their membrane composition
Integral But Forgotten: Metics in Ancient Athens
No full textEvery civilization has contained foreign residents, and Ancient Athens was no exception. In Classical Athens (489-323 BCE), these foreign residents and freed slaves were known as metics. The “metic” label came from the tax they had to pay: the metoikion, or metic tax. While foreign resident status most likely existed throughout city-states across Greece, Athens is the location best documented. Many of these documents come from wills and court cases, giving glimpses of the daily life of Athens’ non-citizen residents. Metics commonly worked as craftsmen, bankers, and people of commerce. Those working class metics helped supplement the Athenian labor force, as many Athenian citizens became soldiers during war. A large number of philosophers also lived as metics, including Aristotle. Yet, although Athenians allowed metics to live and work in their city-state, metics faced numerous legal restrictions, limiting their rights and reinforcing their status as outsiders.
However, while the Athenians treated metics differently from their citizen counterparts, some metics were able to grow great wealth. Although these wealthy banking metics lived more luxurious lives than many Athenian citizens, they always knew that anything they did could lead them to slavery due to the rules against metics. The restrictions all metics faced led to an othering process in the city-state. Metics became excluded from political processes which in-turn separated them from a large social sphere of Athenian Society. Furthermore, all metics continued to be faced with doubt and exploitation by the citizen class, which remains mirrored in today’s society
A General Completeness Theorem for Skip-free Star Algebras
No full textWe consider process algebras with branching parametrized by an equational theory T, and show that it is possible to axiomatize bisimilarity under certain conditions on T. Our proof abstracts an earlier argument due to Grabmayer and Fokkink (LICS\u2720), and yields new completeness theorems for skip-free process algebras with probabilistic (guarded) branching, while also covering existing completeness results
2024 Presidential Election Results
No full textThe data contained in this dataset cover the 2024 Presidential election results. Also included in this dataset are the winner results for the 2016 and 2020 election. Data were sourced from finalized (certified) state election board results wherever possible. All data is reported at the county level. Refer to the Presidential Election General Election 2024 Data Dictionary for a full list of data sources. To view a list of all variables included in this dataset, please see the Presidential Election General Election 2024 Codebook.
This dataset is already prepared for GIS mapping. Data for Alaska and Connecticut is not included in this dataset, because election results are not reported at the county level for these states.
This project was completed by students Ryan Carson \u2728 and Noah Thomas \u2728 as part of The JoAnn Patrick-Ezzell ’75 & Andrew Ezzell Data Science Student Fellows Program through the Dominguez Center for Data Science at Bucknell University
Understanding Resistance to a Secondary Infection in Chronically-Infected Drosophila melanogaster
No full textOur bodies interact with millions of microbes daily, with trillions more already inhabiting our bodies assisting in processes that help us function as humans. However, on some occasions our bodies face invasions from disease-causing microbes and become infected. In some instances the infection cannot be cleared from the body and persists over time as a chronic infection. While chronic infections are energetically costly, they can also prime the immune system to better fight and eliminate a subsequent infection. The goal of this study is to explore the extent that a bacterial infection has on protecting against a second infection and the underlying mechanisms behind this phenomenon. Therefore, three different wild-type Drosophila strains – Canton S, OR, and w1118 – and three different chronic infection lengths – 3, 7, and 14 days – were tested to determine if genetic variation or timing of chronic infection play a significant role in the immune priming phenomenon. To do this, flies were chronically infected, then 3, 7, or14 days later were infected again with a different bacteria or a sterile solution. Survival was tracked, bacterial load analyzed, and antimicrobial peptide expression measured to determine if resistance to an infection differs between wildtype fly lines and across different infection lengths. Overall, w1118 flies had the most robust protection from a second infection at all three infection lengths in part due to bacterial resistance. This work shows the importance of the impact of genetic background in wild type flies while timing between infections did not play a significant role
Theoretical Study of Phase-Ordering Kinetics with an Anisotropic Surface Tension
No full textCoarsening describes the phase-separation dynamics that follows after a temperature quench from a stable to unstable region of the phase diagram in binary systems. Whereas binary systems with an isotropic surface tension have been thoroughly examined and modeled, the case of an anisotropic surface tension lacks the same degree of analysis and development. In this thesis, we demonstrate the self-consistency of the scaling hypothesis with an anisotropic surface tension in the dilute limit. We begin by assuming weak anisotropy in the surface tension and working only to first order in perturbation theory. Following a similar approach laid out in the isotropic theory, we derive an equation of motion in terms of a scaled parameter x ≡ R0/L(t) , where R0 is the isotropic radius of the droplet and L(t) is the characteristic length scale of the system, and t is time. We then solve this equation of motion to observe how the anisotropy in the surface tension influences the drop shape and drop size distribution. We find that the drop size distribution, though different from the isotropic case, may be consistently expressed in terms of the scaled parameter x, thus achieving a self-consistent theory of scaling in the anisotropic case. Furthermore, we find that the characteristic length scale of the system remains the same as the isotropic theory L ∼ t^{1/3}, but we also find that the domain structures are governed by the scaled parameter x rather than assuming their equilibrium shapes (Wulff shapes), in direct opposition to previous expectations