Lepton Flavor Violation and Collider Searches in a Type I + II Seesaw Model

Neutrino are massless in the Standard Model. The most popular mechanism to generate neutrino masses are the type I and type II seesaw, where right-handed neutrinos and a scalar triplet are augmented to the Standard Model, respectively. In this work, we discuss a model where a type I + II seesaw mechanism naturally arises via spontaneous symmetry breaking of an enlarged gauge group. Lepton flavor violation is a common feature in such setup and for this reason, we compute the model contribution to the $\mu \rightarrow e\gamma$ and $\mu \rightarrow 3e$ decays. Moreover, we explore the connection between the neutrino mass ordering and lepton flavor violation in perspective with the LHC, HL-LHC and HE-LHC sensitivities to the doubly charged scalar stemming from the Higgs triplet. Our results explicitly show the importance of searching for signs of lepton flavor violation in collider and muon decays. The conclusion about which probe yields stronger bounds depends strongly on the mass ordering adopted, the absolute neutrino masses and which much decay one considers. In the 1-5 TeV mass region of the doubly charged scalar, lepton flavor violation experiments and colliders offer orthogonal and complementary probes. Thus if a signal is observed in one of the two new physics searches, the other will be able to assess whether it stems from a seesaw framework.Comment: 41 pages, 1 figure, 2 table

Finite-size investigation of scaling corrections in the square-lattice three-state Potts antiferromagnet square-lattice three-state Potts antiferromagnet

We investigate the finite-temperature corrections to scaling in the three-state square-lattice Potts antiferromagnet, close to the critical point at T=0. Numerical diagonalization of the transfer matrix on semi-infinite strips of width $L$ sites, $4 \leq L \leq 14$, yields finite-size estimates of the corresponding scaled gaps, which are extrapolated to $L\to\infty$. Owing to the characteristics of the quantities under study, we argue that the natural variable to consider is $x \equiv L e^{-2\beta}For the extrapolated scaled gaps we show that square-root corrections, in the variable$x$, are present, and provide estimates for the numerical values of the amplitudes of the first-- and second--order correction terms, for both the first and second scaled gaps. We also calculate the third scaled gap of the transfer matrix spectrum at T=0, and find an extrapolated value of the decay-of-correlations exponent,$\eta_3=2.00(1)$. This is at odds with earlier predictions, to the effect that the third relevant operator in the problem would give$\eta_{{\bf P}_{\rm stagg}}=3$, corresponding to the staggered polarization.Comment: RevTex4, 5 pages, 2 .eps figures include

Nanoliposomes for encapsulation and delivery of the potential antitumoral methyl 6-methoxy-3-(4-methoxyphenyl)-1H-indole-2-carboxylate

[Excerpt] Nanoliposomes are new technological developments for the encapsulation and delivery of bioactive agents. Because of their biocompatibility and biodegradability, along with their size, nanoliposomes have potential applications in a vast range of fields, including nanotherapy. Nanoliposomes are able to enhance the performance of bioactive agents by improving their bioavailability, in vitro and in vivo stability, as well as preventing their unwanted interactions with other molecules [1]. Nanoliposomes may contain, in addition to phospholipids, other molecules such as cholesterol (Ch) which is an important component of most natural membranes. The incorporation of Ch can increase stability by modulating the fluidity of the lipid bilayer preventing crystallization of the phospholipid acyl chains and providing steric hindrance to their movement. Further advances in liposome research found that polyethylene glycol (PEG), which is inert in the body, allows longer circulatory life of the drug delivery system [2]. [...]This work was funded by FCT-Portugal and FEDER through CFUM, CQ-UM, Project PTDC/QUI/81238/2006 (cofinanced by FCT and by program FEDER/COMPETE, ref. FCOMP-01-0124-FEDER-007467) and Post-doc. grant of A.S. Abreu (SFRH/BPD/24548/2005)

Studies of encapsulation of new antitumoral fluorescent compounds in nanoliposomes for drug delivery purposes

This work was funded by Foundation for Science and Technology (FCT-Portugal) through CFUM, CQ-UM, Project PTDC/QUI/81238/2006 and Post-doc. grant of A.S. Abreu (SFRH/BPD/24548/2005)

Studies of encapsulation of a new potential antitumoral indole derivative in nanoliposomes for drug delivery applications

This work was funded by FCT-Portugal and FEDER through CFUM, CQ-UM, Project PTDC/QUI/81238/2006 and Post-doc. grant of A.S. Abreu (SFRH/BPD/ /24548/2005)

Synthesis of bis-amino acid derivatives by Suzuki cross-coupling, Michael addition and substitution reactions

Several bis-amino acids were prepared using a bis-Suzuki coupling (compounds 4-8, 10), a sequential Michael addition and bis-Suzuki coupling (compounds 12, 13) and a Michael addition followed by a substitution reaction (compounds 18, 19). Thus, the pure stereoisomer of the methyl esters of N-(tert-butoxycarbonyl)-beta-bromodehydroaminobutyric acid and dehydrophenylalanine and of N-benzyloxycarbonyl-beta-bromodehydroaminobutyric acid were reacted with 1,4-phenylene-bis-boronic acid or 9,9-dioctyl-9H-fluorene-2,7-bis-boronic acid using modified Suzuki coupling conditions. The corresponding bis-dehydroamino acid derivatives were obtained in good to high yields maintaining the stereochemistry of the starting materials. This reaction was also applied successfully to a brominated dehydrodipeptide and 1,4-phenylene-bis-boronic acid showing that it could be used to create cross-links in peptide chains. An N,N-diacyldehydroalanine derivative was used in a sequential Michael addition and bis-Suzuki coupling giving a p-terphenyl bis-amino acid and a fluorenyl bis-amino acid in good yields. Two bis-alpha,beta-diamino acids were obtained by a Michael addition of 1,2,4-triazole to the methyl esters of N-(4-toluenesulfonyl), N-(tert-butoxycarbonyl) dehydroamino acids followed by treatment with ethylenediamine.We acknowledge the Foundation for Science and Technology (FCT), Portugal and the Fundo Europeu de Desenvolvimento Regional (FEDER) for financial support through the Centro de Quimica of University of Minho and through the project POCI/QUI/59407/2004

Fluorescence studies of 2-quinolinones and coumarins including peptide derivatives in solution and in lipid membranes

Photophysical properties of 2-quinolinones and coumarins, including peptide derivatives, were determined. Fluorescence emission and anisotropy measurements of compounds incorporated in lipid vesicles were performed. Our studies indicate that these compounds may be used as fluorescent probes for peptides and lipid membranes.Fundação para a Ciência e a Tecnologia (FCT) and FEDER for financial support to the Research Centres, CFUM [PEst-C/FIS/UI0607/2011 (F-COMP-01-0124-FEDER022711)] and CQ/UM [PEst-C/QUI/UI0686/2011 (FCOMP-01-0124-FEDER-022716)] and to the research project PTDC/QUI/81238/2006 (FCOMP01-0124-FEDER-007467). A.S. Abreu also thanks her post-doctoral grant (SFRH/BPD/24548/2005) to FCT, POPH-QREN, FSE

Palladium-catalyzed borylation and Suzuki coupling (BSC) to obtain beta-substituted dehydroamino acid derivatives

Several benzo[b]thienyldehydroamino acids were prepared by one pot palladium-catalyzed borylation and Suzuki coupling (BSC) from bromobenzo[b]thiophenes containing EDG (OMe or Me), as the component to be borylated with pinacolborane, and pure stereoisomers of beta-bromodehydroamino acid derivatives. To our knowledge it is the first time that the BSC reaction involves a non aromatic system.Fundação para a Ciência e Tecnologia - POCTI/1999/QUI/32689, SFRH/BD/4709/2001

Sonogashira cross-couplings of dehydroamino acid derivatives and phenylacetylenes

Several phenylacetylenes were coupled under Sonogashira cross coupling conditions with the methyl esters of N-(tert-butoxycarbonyl)-(E)-beta-bromo or beta, beta-dibromodehydroalanine to give respectively beta-substituted or beta,beta-bis-substituted dehydroalanines. The beta-substituted dehydroalanines were obtained in good to high yields (60-90%) under the usual Sonogashira conditions (1 equiv. of the phenylacetylene, 1 mol% Pd(PPh3)4, 2 mol% CuI 18 equiv. NEt3 in acetonitrile, 24h at rt) with maintenance of the stereochemistry. The beta,beta-bis-substituted dehydroalanines were in turn obtained in moderate to good yields (44-63%) requiring modified Sonogashira conditions (4 equiv. of the phenylacetylene,10 mol% PdCl2(PPh3)2, 20 mol% CuI, 1.4 equiv. Cs2CO3, 2h at reflux of acetonitrile). In the latter reactions some phenylacetylene dimer and the (E)-isomer of the mono substituted coupled products were also isolated in some extent. The Sonogashira products which were obtained from the 4-bromophenylacetylene were reacted with functionalized benzo[b]thiophenes under C-C or C-N palladium-catalyzed cross-coupling conditions. Preliminary fluorescence studies were performed for mono and disubstituted 4-aminophenylacetylenic dehydroamino acids and for the benzo[b]thiophene derivatives. The results showed that some of the dehydroalanines prepared can be used as fluorescent probes.Fundação para a Ciência e Tecnologia - POCTI/99/QUI/32689, SFRH/BD/4709/2001