Rare Top-quark Decays to Higgs boson in MSSM

In full one-loop generality and in next-to-leading order in QCD, we study rare top to Higgs boson flavour changing decay processes $t\to q h$ with $q=u,c$ quarks, in the general MSSM with R-parity conservation. Our primary goal is to search for enhanced effects on $Br(t\to q h)$ that could be visible at current and high luminosity LHC running. To this end, we perform an analytical expansion of the amplitude in terms of flavour changing squark mass insertions that treats both cases of hierarchical and degenerate squark masses in a unified way. We identify two enhanced effects allowed by various constraints: one from holomorphic trilinear soft SUSY breaking terms and/or right handed up squark mass insertions and another from non-holomorphic trilinear soft SUSY breaking terms and light Higgs boson masses. Interestingly, even with $\mathcal{O}(1)$ flavour violating effects in the, presently unconstrained, up-squark sector, SUSY effects on $Br(t\to q h)$ come out to be unobservable at LHC mainly due to leading order cancellations between penguin and self energy diagrams and the constraints from charge- and colour-breaking minima (CCB) of the MSSM vacuum. An exception to this conclusion may be effects arising from non-holomorphic soft SUSY breaking terms in the region where the CP-odd Higgs mass is smaller than the top-quark mass but this scenario is disfavoured by recent LHC searches. Our calculations for $t\to q h$ decay are made available in SUSY_FLAVOR numerical library.Comment: 32 pages, 6 figures; version accepted for publication in JHEP: additional comparison with literature added, minor misprints correcte

Mass Insertions vs. Mass Eigenstates calculations in Flavour Physics

We present and prove a theorem of matrix analysis, the Flavour Expansion Theorem (or FET), according to which, an analytic function of a Hermitian matrix can be expanded polynomially in terms of its off-diagonal elements with coefficients being the divided differences of the analytic function and arguments the diagonal elements of the Hermitian matrix. The theorem is applicable in case of flavour changing amplitudes. At one-loop level this procedure is particularly natural due to the observation that every loop function in the Passarino-Veltman basis can be recursively expressed in terms of divided differences. FET helps to algebraically translate an amplitude written in mass eigenbasis into flavour mass insertions, without performing diagrammatic calculations in flavour basis. As a non-trivial application of FET up to a third order, we demonstrate its use in calculating strong bounds on the real parts of flavour changing mass insertions in the up- squark sector of the MSSM from neutron Electric Dipole Moment (nEDM) measurements, assuming that CP-violation arises only from the CKM matrix.Comment: 23 page

Bilateral pectoral musculature malformations with concomitant vascular anomaly

We report on a unique combination of multiple variations concerning the pectoral muscles and the left external jugular vein. Specifically, a bilateral hypoplasia of the medial clavicular portion of the pectoralis major muscle was noticed along with the coexistence of total right pectoralis minor aplasia, substituted by loose connective and fatty tissue. Simultaneously, a supernumerary anterior-placed external jugular vein was found, which, after its supraclavicular course, pierced the interval between the left clavicular and the sternocostal head, and drained into the left jugular junction. The combination of the above anomalies constitutes an atypical pattern of Poland syndrome. We discuss the related embryological development and the relative literature. Attention was paid to the clinical importance for plastic surgeons, general surgeons, and radiologists, facilitating them with accurate interpretation of anterior thoracic wall findings. (Folia Morphol 2010; 69, 3: 187-191

The density of virialized clusters as a probe of dark energy

We use the spherical collapse model to demonstrate that the observable average density of virialized clusters depends on the properties of dark energy along with the properties of gravity on cluster scales and can therefore be used as a probe of these properties. As an application of this approach we derive the predicted virialized densities and radii of cluster mass structures for a wide range of values of the cosmological constant (including negative values) as a function of the turnaround redshift. For the value of $\Omega_{\Lambda,0}=-0.7$ (with $\Omega_{m,0}=0.3$) preferred by $\Lambda$ sign-switching models ($\Lambda_s\text{CDM}$) proposed for the resolution of the Hubble and $S_8$ tensions, we find an amplification of the density of virialized clusters which can be as large as $80\%$ compared to \plcdm for a turnaround redshift $z_{\text{max}} \gtrsim 2$. Such an amplification may lead to more efficient early galaxy formation in this class of models in accordance with the recent findings of JWST.Comment: 12 pages, 8 figure

Aligning strategy to threat: a baseline anti-terrorism strategy for hotels

Purpose – Although the threat of terrorist attacks is not a new phenomenon for hotels, limited literature exists on measures that hotels can take to prevent them or limit their damage. The purpose of this paper is to propose a baseline strategy to address this threat. Design/methodology/approach – Using the terrorist attack cycle and the security function models introduced in this paper, 19 hotel security experts, members of an international working group on terrorism, were tasked to reach consensus on a baseline anti-terrorist strategy for a hotel. To reach this consensus, the study employed the Nominal Group Technique. Findings – The study presents a six-step baseline anti-terrorism strategy and a series of measures and actions under each step. In the centre of this strategy lies the disruption of the terrorist attack cycle. Research limitations/implications – There are limitations inherent to the Nominal Group Technique which may not allow the generalizability of the findings. However, every effort was made to ensure the reliability and validity of the study. Practical implications – The study suggests a shift from physical protection alone to a more intelligence-led approach. Counter-surveillance, terrorist behavioral analysis, higher visibility of security measures, stronger relationships with local community leaders, collaborative relationships with emergency response agencies and strategic use of risk intelligence providers will have to take a higher place in the agendas of hotel security departments. Originality/value – The paper presents, for the first time, two models that industry practitioners will find useful when designing security policies: the terrorist attack cycle and the security function model. Each component of the proposed strategy provides a starting point for the design of security strategies tailored on the security needs and budget of any hotel property