Markierungsverfahren zur Synthese 4-[18F]Fluorprolyl-haltiger Peptide

The requirement of selective radiopharmaceuticals for PET-diagnostics necessitates the development of new labelling methods taking into account the substantial and structural diversity of the compounds to be labelled . Therefore different concepts for $^{18}$F-fluorination of peptides, which are increasingly important as pharmaceuticals, via proline moieties were explored and evaluated in this work. The direct nucleophilic kryptate based $^{18}$F-fluorination of the model peptide Z-Pro-Leu-Gly-4- (4R)-(TsO)Pro-OMe showed, that the peptide is not stable under the basic labelling conditions, and as a result the $^{18}$F-fluorination is not possible. Perfluorbutane-l-sulfonyl[ $^{18}$F]fluoride is a possible reagent for $^{18}$F-fluorination of sensitive hydroxy groups containing biomolecules due to the mild reaction conditions at which aliphatic alcohols are fluorinated by this reagent. By kryptate catalysed, nucleophilic $^{18}$F-fluorination of N,N-bis(perfluorobutane-l-sulfonyl)aniline and evaporation of the active product no-carrier-added perfluorobutane-l-sulfonyl[ $^{18}$F]fluoride can be achieved either dissolved in toluene (RCY: 83 ± 3 %) or adsorbed an a polystyrole-matrix (LiChrolut$^{®}$ EN) with a total yield of 75 ± 6 %. In the presence of an equimolar amount of perfluorobutane-1-sulfonylfluoride as carrier N-Boc-Hyp- OMe can be $^{18}$F-fluorinated with a radiochemical yield of > 90 % and the two model peptides Z-Pro- Leu-Gly-Hyp-OMe and Z-Gly-Leu-Hyp-Gly-Leu-OMe with 40 - 45 % and 30 - 35 %, while in the case of no-carrier-added synthesis only ca. 1 % of the $^{18}$F-fluoroproduct is obtained . The necessary addition of perfluorobutane-l-sulfonylfluoride carrier allows naturally only the synthesis of radiotracers with low molar activity. For performance of the $^{18}$F-fluorination via perfluorobutane-l-sulfonyl[ $^{18}$F]fluoride of the model peptide N-Boc-Hyp-Leu-OH, which is covalently bound to a Wang resin via the C-terminus, the $^{18}$F-fluorination reagent is prepared in absence of a solvent and adsorbed an the Wang resin with a yield of 31 ± 3 %, based on [$^{18}$F]fluoride. The subsequent $^{18}$F-fluorination of the peptide, which was done in the presence of an equimolar amount of perfluorobutane-1-sulfonylfluoride, proceeds with a radiochemical yield of merely 4 ± 1 %. Altematively, the condensation of 4-[$^{18}$F]fluoroproline-methylester via TBTU at the C-terminus of Z-Pro-Leu-Gly-OH could be carried out under no-carrrier-added conditions with a radiochemical yield of 70 - 80 %. The required 4-[$^{18}$F]fluoroproline-methylester could be achieved with a radiochemical yield of 30 - 40 % by $^{18}$F-substitution of N-Boc-trans-4-(ptoluenesulfonyloxy)- proline-methylester, by which the trans-product is also formed in addition to the cis-product, and the cleavage of the Boc group. As a result of these studies another prosthetic group is available for no-carrier-added labelling of peptides

SO(10)SO(10) inspired extended GMSB models

Influence of messenger-matter superpotential interactions on the renormalization of Yukawa couplings in the context of extended GMSB models is analysed. We present a convenient method for treating decoupling of messengers and related redefinition of MSSM fields. Discussed approach is used to study top-bottom-tau Yukawa unification within specific $SO(10)$ inspired GUT model.Comment: 10 pages, 2 figures; submitted to the Proceedings of the Corfu Summer Institute 2014 "School and Workshops on Elementary Particle Physics and Gravity", 3-21 September 2014 Corfu, Greec

On messengers couplings in extended GMSB models

We discuss, for the first time, the role of the superpotential couplings of three messenger fields in a GMSB-type unification model in which messenger sector consists of both 5+5bar and 10+10bar of SU(5). It turns out that these interactions are relevant when coexist with appropriate messenger-MSSM couplings. Then they induce extra contributions to 2-loop soft masses. In the present model, we derive all such soft terms and discuss constraints which have to be satisfied to avoid rapid proton decay and mu/B_mu problem. As an example, it is shown how superpotential couplings of three messengers influence mass spectra when the model is restricted by additional global U(1)_q symmetry. We find that masses of the lightest sleptons are the most sensitive to those new interactions, what in some cases results in the NLSP/NNLSP pattern in which stau or selectron is lighter than the lightest neutralino.Comment: 20 pages, 3 figures, 16 table

Heavy neutrinos and the pp→lljjpp\to lljj CMS data

We show that the excess in the $pp \to ee jj$ CMS data can be naturally interpreted within the Minimal Left Right Symmetric model (MLRSM), keeping $g_L = g_R$, if CP phases and non-degenerate masses of heavy neutrinos are taken into account. As an additional benefit, a natural interpretation of the reported ratio (14:1) of the opposite-sign (OS) $pp\to l^\pm l^\mp jj$ to the same-sign (SS) $pp\to l^\pm l^\pm jj$ lepton signals is possible. Finally, a suppression of muon pairs with respect to electron pairs in the $pp \to lljj$ data is obtained, in accordance with experimental data. If the excess in the CMS data survives in the future, it would be a first clear hint towards presence of heavy neutrinos in right-handed charged currents with specific CP phases, mixing angles and masses, which will have far reaching consequences for particle physics directions.Comment: 8 pages, 7 figures. v2: minor changes, refs added, typos corrected, version accepted for publication in PL

Analytical two-loop soft mass terms of sfermions in Extended GMSB models

Analytical two-loop contributions to soft masses of sfermions are derived in the Extended GMSB (EGMSB) model with one superpotential coupling between matter and messenger superfields. Analytical results allows to study in detail the whole range of the ratio $F/M^2$ of the spurion $F$-term, $F$, to the messenger scale $M$. It is shown that if $F/M^2$ is of the order of $1$, then one- and two-loop contributions to soft masses are of the same magnitude and their interplay leads to novel sfermion mass patterns.Comment: 8 pages, 5 figures. v2: typos corrected, figures added, discussion in the Sec. 5 extende

Investigating techniques in the generation of support software

The performance of the Meta assembler processor software package previously provided for the Space Ultrareliable Modular Computer (SUMC) at the Marshall Space Flight Center (MSFC) was verified. A number of adjustments were made to the processor following the rehosting of the SUMC software development facility (S4) on a newly acquired IBM 360/65. The assembler was configured to provide cross assembly capability for various target computers

Theoretical constraints on masses of heavy particles in Left-Right Symmetric Models

Left-Right symmetric models with general $g_L \neq g_R$ gauge couplings which include bidoublet and triplet scalar multiplets are studied. Possible scalar mass spectra are outlined by imposing Tree-Unitarity, and Vacuum Stability criteria and also using the bounds on neutral scalar masses $M_{\rm H^{ FCNC}}$ which assure the absence of Flavour Changing Neutral Currents (FCNC). We are focusing on mass spectra relevant for the LHC analysis, i.e., the scalar masses are around TeV scale. As all non-standard heavy particle masses are related to the vacuum expectation value (VEV) of the right-handed triplet ($v_R$), the combined effects of relevant Higgs potential parameters and $M_{\rm H^{ FCNC}}$ regulate the lower limits of heavy gauge boson masses. The complete set of Renormalization Group Evolutions for all couplings are provided at the 1-loop level, including the mixing effects in the Yukawa sector. Most of the scalar couplings suffer from the Landau poles at the intermediate scale $Q \sim 10^{6.5}$ GeV, which in general coincides with violation of the Tree-Unitarity bounds.Comment: 9 pages, 5 figures, pdflatex, Matches published versio

Aisling Jelinski Senior Art Exhibition Portfolio

Aisling Jelinski\u27s Senior Art Exhibition Portfolio, completed in Spring 2018 as a part of the Senior Art Capstone. These five pieces are a part of the series What Was True Is False, inspired by Hellenistic and Classical sculpture, the stories behind them, and the relationship between history and knowledge.https://digitalcommons.snc.edu/artportfolios/1016/thumbnail.jp