Neutrino CP violating parameters from nontrivial quark-lepton correlation: a S3xGUT model

We investigate the prediction on the lepton phases in theories with a non trivial correlation between quark (CKM) and lepton (PMNS) mixing matrices. We show that the actual evidence, under the only assumption that the correlation matrix $V^M$ product of $CKM$ and $PMNS$ has a zero in the entry $(1,3)$, gives us a prediction for the three CP-violating invariants $J$, $S_1$, and $S_2$. A better determination of the lepton mixing angles will give a strong prediction of the CP-violating invariants in the lepton sector. These will be tested in the next generation experiments. To clarify how our prediction works, we show how a model based on a Grand Unified Theory and the permutation flavor symmetry $S_3$ predicts $V^M_{13}=0$.Comment: 7 pages, 3 figures. V2: new figure adde

Low energy n-\nuc{3}{H} scattering : a novel testground for nuclear interaction

The low energy n-\nuc{3}{H} elastic cross sections near the resonance peak are calculated by solving the 4-nucleon problem with realistic NN interactions. Three different methods -- Alt, Grassberger and Shandas (AGS), Hyperspherical Harmonics and Faddeev-Yakubovsky -- have been used and their respective results are compared. We conclude on a failure of the existing NN forces to reproduce the n-\nuc{3}{H} total cross section.Comment: To be published in Phys. Rev.

Market segments based on the dominant movement patterns of tourists

This paper presents an innovative method for tourist market segmentation-based on dominant movement patterns of tourists; that is, the travel sequences or patterns used by tourists most frequently. There were three steps to achieve this goal. In the first step, general log-linear models were adopted to identify the dominant movement patterns, while the second step was to discover the characteristics of the groups of tourists who travelled with these patterns. The Expectation–Maximisation algorithm was then used to partition tourist segments in terms of socio-demographic and travel behavioural variables. The third step was to select target markets based upon the earlier analysis. These methods were applied to a sample of tourists, over the period of a week, on Phillip Island, Victoria, Australia. A significant outcome of this research is that it will assist tourism organisations to identify tourism market segments and develop better tour packages and more efficient marketing strategies aligned to the characteristics of the tourists

Recognition of Membrane Sterols by Polyene Antifungals Amphotericin B and Natamycin, A 13C MAS NMR Study

The molecular action of polyene macrolides with antifungal activity, amphotericin B and natamycin, involves recognition of sterols in membranes. Physicochemical and functional studies have contributed details to understanding the interactions between amphotericin B and ergosterol and, to a lesser extent, with cholesterol. Fewer molecular details are available on interactions between natamycin with sterols. We use solid state 13C MAS NMR to characterize the impact of amphotericin B and natamycin on mixed lipid membranes of DOPC/cholesterol or DOPC/ergosterol. In cholesterol-containing membranes, amphotericin B addition resulted in marked increase in both DOPC and cholesterol 13C MAS NMR linewidth, reflecting membrane insertion and cooperative perturbation of the bilayer. By contrast, natamycin affects little either DOPC or cholesterol linewidth but attenuates cholesterol resonance intensity preferentially for sterol core with lesser impact on the chain. Ergosterol resonances, attenuated by amphotericin B, reveal specific interactions in the sterol core and chain base. Natamycin addition selectively augmented ergosterol resonances from sterol core ring one and, at the same time, from the end of the chain. This puts forward an interaction model similar to the head-to-tail model for amphotericin B/ergosterol pairing but with docking on opposite sterol faces. Low toxicity of natamycin is attributed to selective, non-cooperative sterol engagement compared to cooperative membrane perturbation by amphotericin B

Conducting research with individuals at risk for suicide: protocol for assessment and risk management

Published in final edited form as: Suicide Life Threat Behav. 2020 April ; 50(2): 461–471. doi:10.1111/sltb.12602.OBJECTIVE: Suicide prediction, prevention, and intervention are urgent research areas. One barrier for research with high‐risk populations is limited resources to manage risk in a research setting. We describe using the University of Washington Risk Assessment Protocol (UWRAP) to assess and manage suicide risk during phone‐administered eligibility assessments in two clinical trials. METHOD: Study 1 (N = 151) recruited suicidal adults who were not engaged in mental health treatment and Study 2 (N = 135) recruited suicidal adults who used alcohol to regulate emotions. Pre‐ and postassessment ratings of stress, urge to harm self, urge to use drugs/alcohol, and intent to harm self were compared and strategies to manage increased suicide risk following screening interviews were implemented, as indicated. RESULTS: In both studies, average postassessment ratings were significantly lower than pre‐assessment. A minority of participants reported higher ratings on one or more domains; however, following more thorough suicide risk assessment, risk was appropriately managed by providing low‐level interventions (e.g., validation). CONCLUSIONS: Suicide risk in research involving community participants can be managed by using appropriate risk protocols.Published versio

Solutions of the Faddeev-Yakubovsky equations for the four nucleons scattering states

The Faddeev-Yakubowsky equations in configuration space have been solved for the four nucleon system. The results with an S-wave interaction model in the isospin approximation are presented. They concern the bound and scattering states below the first three-body threshold. The elastic phase-shifts for the N+NNN reaction in different ($S,T$) channels are given and the corresponding low energy expansions are discussed. Particular attention is payed to the n+t elastic cross section. Its resonant structure is well described in terms of a simple NN interaction. First results concerning the S-matrix for the coupled N+NNN-NN+NN channels and the strong deuteron-deuteron scattering length are obtained.Comment: latex.tar.gz, 36 pages, 10 figures, 11 tables. To be published in Physical Review

Few-nucleon systems in translationally invariant harmonic oscillator basis

We present a translationally invariant formulation of the no-core shell model approach for few-nucleon systems. We discuss a general method of antisymmetrization of the harmonic-oscillator basis depending on Jacobi coordinates. The use of a translationally invariant basis allows us to employ larger model spaces than in traditional shell-model calculations. Moreover, in addition to two-body effective interactions, three- or higher-body effective interactions as well as real three-body interactions can be utilized. In the present study we apply the formalism to solve three and four nucleon systems interacting by the CD-Bonn nucleon-nucleon potential. Results of ground-state as well as excited-state energies, rms radii and magnetic moments are discussed. In addition, we compare charge form factor results obtained using the CD-Bonn and Argonne V8' NN potentials.Comment: 25 pages. RevTex. 13 Postscript figure

DNA synthesis determines the binding mode of the human mitochondrial single-stranded DNA-binding protein

[EN] Single-stranded DNA-binding proteins (SSBs) play a key role in genome maintenance, binding and organizing single-stranded DNA (ssDNA) intermediates. Multimeric SSBs, such as the human mitochondrial SSB (HmtSSB), present multiple sites to interact with ssDNA, which has been shown in vitro to enable them to bind a variable number of single-stranded nucleotides depending on the salt and protein concentration. It has long been suggested that different binding modes might be used selectively for different functions. To study this possibility, we used optical tweezers to determine and compare the structure and energetics of long, individual HmtSSB¿DNA complexes assembled on preformed ssDNA and on ssDNA generated gradually during `in situ¿ DNA synthesis. We show that HmtSSB binds to preformed ss-DNA in two major modes, depending on salt and protein concentration. However, when protein binding was coupled to strand-displacement DNA synthesis, only one of the two binding modes was observed under all experimental conditions. Our results reveal a key role for the gradual generation of ssDNA in modulating the binding mode of a multimeric SSB protein and consequently, in generating the appropriate nucleoprotein structure for DNA synthetic reactions required for genome maintenance.We are grateful to Prof. M. Salas laboratory (CBMSO-CSIC) for generously providing the Phi29 DNA polymerase and to Juan P. García Villaluenga (UCM) for useful discussions. Spanish Ministry of Economy and Competitiveness [MAT2015-71806-R to J.R.A-G, FIS2010-17440, FIS2015-67765-R to F.J.C., BFU2012-31825, BFU2015-63714-R to B.I.]; Spanish Ministry of Education, Culture and Sport [FPU13/02934 to J.J., FPU13/02826 to E.B-H.]; National Institutes of Health [GM45925 to L.S.K.]; University of Tampere (to G.L.C.); Programa de Financiacion Universidad Complutense de Madrid-Santander Universidades [CT45/15-CT46/15 to F.C.]. Funding for open access charge: Spanish Ministry of Economy and Competitiveness [BFU2015-63714-R].Morin, J.; Cerrón, F.; Jarillo, J.; Beltran-Heredia, E.; Ciesielski, G.; Arias-Gonzalez, JR.; Kaguni, L.... (2017). DNA synthesis determines the binding mode of the human mitochondrial single-stranded DNA-binding protein. Nucleic Acids Research. 45(12):7237-7248. https://doi.org/10.1093/nar/gkx395S723772484512Shereda, R. D., Kozlov, A. G., Lohman, T. M., Cox, M. M., & Keck, J. L. (2008). 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Four-nucleon shell-model calculations in a Faddeev-like approach

We use equations for Faddeev amplitudes to solve the shell-model problem for four nucleons in the model space that includes up to 14 hbar Omega harmonic-oscillator excitations above the unperturbed ground state. Two- and three-body effective interactions derived from the Reid93 and Argonne V8' nucleon-nucleon potentials are used in the calculations. Binding energies, excitations energies, point-nucleon radii and electromagnetic and strangeness charge form factors for 4He are studied. The structure of the Faddeev-like equations is discussed and a formula for matrix elements of the permutation operators in a harmonic-oscillator basis is given. The dependence on harmonic-oscillator excitations allowed in the model space and on the harmonic-oscillator frequency is investigated. It is demonstrated that the use of the three-body effective interactions improves the convergence of the results.Comment: 22 pages, 13 figures, REVTe

Total 4He Photoabsorption Cross Section Revisited: Correlated HH versus Effective Interaction HH

Two conceptually different hyperspherical harmonics expansions are used for the calculation of the total 4He photoabsorption cross section. Besides the well known method of CHH the recently introduced effective interaction approach for the hyperspherical formalism is applied. Semi-realistic NN potentials are employed and final state interaction is fully taken into account via the Lorentz integral transform method. The results show that the effective interaction leads to a very good convergence, while the correlation method exhibits a less rapid convergence in the giant dipole resonance region. The rather strong discrepancy with the experimental photodisintegration cross sections is confirmed by the present calculations.Comment: LaTeX, 7 pages, 3 ps figure