Alien Registration- Racila, Clementina (Dover-Foxcroft, Piscataquis County)

https://digitalmaine.com/alien_docs/10369/thumbnail.jp

Synthesis of donor-acceptor benzobis(oxazole) small molecules

A variety of symmetric, π-conjugated organic chromophores were synthesized using trans-benzobis(oxazole) as an acceptor and the core of dye, changing the donating moieties in the 2- and 6-positions. The optical and electrical properties of these compounds were investigated for potential use in organic electronic devices, and these compounds exhibited relatively narrow band-gaps, which were tuned by changing the donating group present. Additionally, a significant solvatochromatic effect was noted for some of the dyes. Synthetic routes towards asymmetric chromophores using benzobis(oxazole)s as a π-spacer between an electron-acceptor and donor were also developed, using the orthoester condensation and an intramolecular Beckmann rearrangement as orthogonal oxazole ring-closing methods. To broaden the availability of conjugated compounds for use in the orthoester condensation, significant progress was also made on the synthesis of previously unknown orthoesters

Alien Registration- Klimavicz, Stafania U. (Dover-Foxcroft, Piscataquis County)

https://digitalmaine.com/alien_docs/10382/thumbnail.jp

A dual-target molecular mechanism of pyrethrum repellency against mosquitoes

Pyrethrum extracts from flower heads of Chrysanthemum spp. have been used worldwide in insecticides and repellents. While the molecular mechanisms of its insecticidal action are known, the molecular basis of pyrethrum repellency remains a mystery. In this study, we find that the principal components of pyrethrum, pyrethrins, and a minor component, (E)-β-farnesene (EBF), each activate a specific type of olfactory receptor neurons in Aedes aegypti mosquitoes. We identify Ae. aegypti odorant receptor 31 (AaOr31) as a cognate Or for EBF and find that Or31-mediated repellency is significantly synergized by pyrethrin-induced activation of voltage-gated sodium channels. Thus, pyrethrum exerts spatial repellency through a novel, dual-target mechanism. Elucidation of this two-target mechanism may have potential implications in the design and development of a new generation of synthetic repellents against major mosquito vectors of infectious diseases

Synthesis of donor-acceptor benzobis(oxazole) small molecules

A variety of symmetric, π-conjugated organic chromophores were synthesized using trans-benzobis(oxazole) as an acceptor and the core of dye, changing the donating moieties in the 2- and 6-positions. The optical and electrical properties of these compounds were investigated for potential use in organic electronic devices, and these compounds exhibited relatively narrow band-gaps, which were tuned by changing the donating group present. Additionally, a significant solvatochromatic effect was noted for some of the dyes. Synthetic routes towards asymmetric chromophores using benzobis(oxazole)s as a π-spacer between an electron-acceptor and donor were also developed, using the orthoester condensation and an intramolecular Beckmann rearrangement as orthogonal oxazole ring-closing methods. To broaden the availability of conjugated compounds for use in the orthoester condensation, significant progress was also made on the synthesis of previously unknown orthoesters.</p

Biorational pesticides: Pest control inspired by natural compounds

Over the last several hundred million years, plants have evolved to produce an incredible variety of secondary metabolites. Many of these compounds are repellent or insecticidal and are generated by the plant to reduce herbivory. However, these compounds frequently lack the ideal chemical and physical properties that would make them suitable for larger-scale use as insect repellents or agricultural insecticides. Using a biorational approach, it is possible to chemically modify these natural metabolites to produce new compounds that are more ideal for commercialization. Plant essential oils often contain a variety of monoterpenoids in high abundance, and these components of the oil are usually very fragrant. Although some of these compounds may be highly repellent or toxic to insects, the high volatility of these chemicals typically makes them unsuitable for use as long-lasting spatial insect repellents. The first part of this dissertation explores the chemical modification of monoterpenoid alcohols by esterification, which leads to compounds with higher molecular weight, and a concomitant drop in volatility, while maintaining satisfactory repellency characteristics against Culex pipiens, the northern house mosquito. Slight changes in the structure of the parent monoterpenoid or the esterifying group can often lead to substantial differences in potency of the repellency, and several of the synthesized compounds were repellent for more than seven hours against C. pipiens. Plant-parasitic nematodes are a tremendous economic burden throughout the world, and although several terpenoids and phenylpropanoids have been shown to be somewhat toxic to some of these nematodes, treatment of infected soil is still often cost-prohibitive. A biorational approach was used to develop analogs of cinnamaldehyde, a compound previously shown to be effective against multiple species of nematodes in in vitro assays. Many of these compounds were significantly more potent against the soybean cyst nematode (Heterodera glycines) than the parent compound. The synthesis of analogs of a natural compound is an integral part of the biorational design of pesticides. The last portion of this dissertation focuses on two new synthetic methods, one for producing ketene dithioacetals, and one on the synthesis of 1,2,4-thiadiazoles. Both of these classes of compounds have been underexplored in agricultural chemistry, and the existing methods of creating these chemicals are limited. The new methods make these compounds in acceptable-to-good yields from readily-available starting materials.</p

Alien Registration- Racila, Clementina (Dover-Foxcroft, Piscataquis County)

https://digitalmaine.com/alien_docs/10369/thumbnail.jp

Alien Registration- Klimavicz, Stafania U. (Dover-Foxcroft, Piscataquis County)

https://digitalmaine.com/alien_docs/10382/thumbnail.jp

Energy Landscapes of Mini-Dumbbell DNA Octanucleotides.

Single-stranded DNA structures play a significant role in biological systems, in particular during replication, translation, and DNA repair. Tracts of simple repetitive DNA are associated with slipped-strand mispairing, which can lead to genetic diseases. Recent NMR studies of TTTA and CCTG repeats have shown that these sequences form mini-dumbbells (MDBs), leading to frameshift mutations. Here we explore the energy landscapes of (CCTG)2 and (TTTA)2, which are currently the smallest known molecules to form MDBs. While (CCTG)2 MDBs are stable, (TTTA)2 exhibits numerous other structures with lower energies. A key factor identified in the stabilization of MDB structures is the bonding strength between residues 1 and 4, and 5 and 8.PhD studentship EPSR

Antibody Profiling by Luciferase Immunoprecipitation Systems (LIPS)

Technologies for comprehensively understanding and quantifying antibody profiles to autoantigens and infectious agents may yield new insights into disease mechanisms and may elucidate new markers to substratify disease with different clinical features and better understand pathogenesis. We have developed a highly quantitative method called Luciferase Immunoprecipitation Systems (LIPS) for profiling patient sera antibody responses to autoantigens and pathogen antigens associated with infection. Unlike ELISAs, the highly sensitive LIPS is easily implemented to survey humoral serological response profiles to different antigens in a universal format and produces dynamic antibody titer ranges up to 6 log10 for some antigens. In these studies, quantitative profiling by LIPS of patient humoral responses against panels of antigens or even the entire proteome of some pathogens (i.e. HIV), is typically more informative than testing a single antigen by ELISA. In addition, LIPS also eliminates time and effort needed to produce highly purified antigens as well as the labor-intensive assay optimization steps needed for standard ELISAs. Here we provide a detailed protocol describing the technical aspects of performing LIPS assays for readily profiling antibody responses to single or multiple antigens