Hint of Lepton Flavour Non-Universality in BB Meson Decays

The LHCb collaboration has recently presented their result on R_K = BR(B+ -> K+ mu+ mu-)/ BR(B+ -> K+ e+ e-) for the dilepton invariant mass bin m_{ll}^2 = 1-6 GeV^2 (l = mu, e). The measurement shows an intriguing 2.6 sigma deviation from the Standard Model (SM) prediction. In view of this, we study model independent New Physics (NP) explanations of R_K consistent with other measurements involving b -> s l l transition, relaxing the assumption of lepton universality. We perform a Bayesian statistical fit to the NP Wilson Coefficients and compare the Bayes Factors of the different hypotheses in order to quantify their goodness-of-fit. We show that the data slightly favours NP in the muon sector over NP in the electron sector.Comment: Final version, to appear in JHE

Linear flavour violation and anomalies in B physics

We propose renormalizable models of new physics that can explain various anomalies observed in decays of B-mesons to electron and muon pairs. The new physics states couple to linear combinations of Standard Model fermions, yielding a pattern of flavour violation that gives a consistent fit to the gamut of flavour data. Accidental symmetries prevent contributions to baryon- and lepton-number-violating processes, as well as enforcing a loop suppression of new physics contributions to flavour violating processes. Data require that the new flavour-breaking couplings are largely aligned with the Yukawa couplings of the SM and so we also explore patterns of flavour symmetry breaking giving rise to this structure.Comment: v2: 28 pages, 10 figures. Added two appendices to make the SU(2) structure of the model clearer, and to discuss Z/photon penguin contributions. Updated a bound on Bs mixing, and added references. Conclusions unchanged. Version to appear in JHE

Renewable sources urban cells microgrid. A case study

Nowadays, microgrid technologies play a relevant role in the research field as well as in the commercial market. The opportunity to provide electricity in wide areas without using centralized electrical infrastructure networks is a reliable key for achieving the European Union sustainability goals. In this regard, the proposed research aims at describing an electric microgrid configuration powered by a photovoltaic system, supplying three school buildings located in the center of Italy. Additionally, the resilience theme is deeply investigated, analyzing the use of an emergency generator system (EGS) in case of electric grid blackouts. MATLAB/Simulink was chosen to simulate the users’ energy demand as well as to calculate the microgrid performance. Results show that almost the total consumption of the microgrid is covered by the photovoltaic system, and the use of an EGS allows energy resilience and moderate economic savings for the communit

longitudinal assessment of neutrophil to lymphocyte ratio nlr from diagnosis until death reveals a biphasic trend in metastatic pancreatic adenocarcinoma patients

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Gravitino Dark Matter in Tree Level Gauge Mediation with and without R-parity

We investigate the cosmological aspects of Tree Level Gauge Mediation, a recently proposed mechanism in which the breaking of supersymmetry is communicated to the soft scalar masses by extra gauge interactions at the tree level. Embedding the mechanism in a Grand Unified Theory and requiring the observability of sfermion masses at the Large Hadron Collider, it follows that the Lightest Supersymmetric Particle is a gravitino with a mass of the order of 10 GeV. The analysis in the presence of R-parity shows that a typical Tree Level Gauge Mediation spectrum leads to an overabundance of the Dark Matter relic density and a tension with the constraints from Big Bang Nucleosynthesis. This suggests to relax the exact conservation of the R-parity. The underlying SO(10) Grand Unified Theory together with the bounds from proton decay provide a rationale for considering only bilinear R-parity violating operators. We finally analyze the cosmological implications of this setup by identifying the phenomenologically viable regions of the parameter space.Comment: 28 pages, 5 figures. References added. To appear in JHE

General Aspects of Tree Level Gauge Mediation

Tree level gauge mediation (TGM) may be considered as the simplest way to communicate supersymmetry breaking: through the tree level renormalizable exchange of heavy gauge messengers. We study its general structure, in particular the general form of tree level sfermion masses and of one loop, but enhanced, gaugino masses. This allows us to set up general guidelines for model building and to identify the hypotheses underlying the phenomenological predictions. In the context of models based on the "minimal" gauge group SO(10), we show that only two "pure" embeddings of the MSSM fields are possible using $d< 120$ representations, each of them leading to specific predictions for the ratios of family universal sfermion masses at the GUT scale, $m^2_{\bar{5}} = 2 m^2_{10}$ or $m^2_{\bar{5}} = (3/4) m^2_{10}$ (in SU(5) notation). These ratios are determined by group factors and are peculiar enough to make this scheme testable at the LHC. We also discuss three possible approaches to the $\mu$-problem, one of them distinctive of TGM.Comment: 37 pages, 2 figure

Comparison of multiple techniques for endobronchial ultrasound-transbronchial needle aspiration specimen preparation in a single institution experience.

The optimal method for specimen preparation of endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) is still controversial. This study aims to compare several techniques available for EBUS-TBNA specimen acquisition and processing, in order to identify the best performing technique. We retrospectively reviewed the data of 199 consecutive patients [male, 73%; median age, 64 years (IQR: 52-74 years)] undergoing EBUS-TBNA at our institution from 2012 through 2014 for diagnosis of hilar-mediastinal lymph node enlargement suspect of neoplastic (n=139) or granulomatous (n=60) disease. All procedures were performed by two experienced bronchoscopists, under conscious sedation and local anaesthesia, using 21/22-Gauge (G) needle, without rapid on-site evaluation (ROSE). Five specimen-processing techniques were used: cytology slides in 42 cases (21%); cell-block in 25 (13%); core-tissue in 60 (30%); combination of cytology slides and core-tissue in 51 (26%); combination of cytology slides and cell-block in 21 (10%). To assess the diagnostic accuracy of each tissue-processing technique we compared the EBUS-TBNA results to those obtained with surgical lymphadenectomy, or 1-year follow-up in non-operated patients. Diagnostic yield, accuracy and area under the curve (AUC) were as follows. Cytology slides: 81%, 80%, 0.90; cell-block: 48%, 33%, 0.67; core-tissue: 87%, 99%, 0.96; cytology slides + core-tissue: 80%, 100%, 1.00; cytology slides + cell-block: 86%, 100%, 1.00. Cytology slides and core-tissue method showed non-significantly different diagnostic yield (P=0.435) and AUC (P=0.152). In our single-institution experience, cytology slides and core-tissue preparations demonstrated high and similar diagnostic performance. Cytology slides combination with core-tissue or cell-block showed the highest performance, however these combination methods were more resource-consuming

Loss of function and reduced levels of sphingolipid desaturase DEGS1 variants are both relevant in disease mechanism

The last step of ex novo ceramide biosynthesis consists of the conversion of dihydroceramide into ceramide catalyzed by sphingolipid Δ4-desaturase DEGS1. DEGS1 variants were found to be responsible for heterogeneous clinical pictures belonging to the family of hypomyelinating leukodystrophies. To investigate the mechanisms making such variants pathogenic, we designed a procedure for the efficient detection of desaturase activity in&nbsp;vitro using LC-MS/MS and prepared a suitable cell model knocking out DEGS1 in HEK-293T cells through CRISPR-Cas9 genome editing (KO-DES-HEK). Transfecting KO-DES-HEK cells with DEGS1 variants, we found that their transcripts were all overexpressed as much as the WT transcripts, while the levels of cognate protein were 40%-80% lower. In&nbsp;vitro desaturase activity was lost by many variants except L175Q and N255S, which maintain a catalytic efficiency close to 12% of the WT enzyme. Metabolic labeling of KO-DES-HEK with deuterated palmitate followed by LC-MS/MS analysis of the formed sphingolipids revealed that the ceramide/dihydroceramide and sphingomyelin/dihydrosphingomyelin ratios were low and could be reverted by the overexpression of WT DEGS1 as well as of L175Q and N255S variants, but not by the overexpression of all other variants. Similar analyses performed on fibroblasts from a patient heterozygous for the N255S variant showed very low variant DEGS1 levels and a low ratio between the same unsaturated and saturated sphingolipids formed upon metabolic labeling, notwithstanding the residual activity measured at high substrate and homogenate protein concentrations. We conclude that loss of function and reduced protein levels are both relevant in disease pathogenesis

Higgs decay with monophoton + MET signature from low scale supersymmetry breaking

We study the decay of a standard model-like Higgs boson into a gravitino and a neutralino, which subsequently decays promptly into another gravitino and a photon. Such a decay can be important in scenarios where the supersymmetry breaking scale is of the order of a few TeV, and in the region of low transverse momenta of the photon, it may provide the dominant contribution to the final state with a photon and two gravitinos. We estimate the relevant standard model backgrounds and the prospects for discovering this Higgs decay through a photon and missing transverse energy signal at the LHC in terms of a simplified model. We also give an explicit model with manifest, but spontaneously broken, supersymmetry in which the usual MSSM soft terms are promoted to supersymmetric operators involving a dynamical goldstino supermultiplet. This model can give rise to a SM-like CP-even neutral Higgs particle with a mass of 125 GeV, without requiring substantial radiative corrections, and with couplings sufficiently large for a signal discovery through the above mentioned Higgs decay channel with the upcoming data from the LHC.Comment: 28 pages, 5 figures, 4 tables; v2: updated to JHEP version, references adde

Les Houches 2015: Physics at TeV colliders - new physics working group report

We present the activities of the 'New Physics' working group for the 'Physics at TeV Colliders' workshop (Les Houches, France, 1-19 June, 2015). Our report includes new physics studies connected with the Higgs boson and its properties, direct search strategies, reinterpretation of the LHC results in the building of viable models and new computational tool developments. Important signatures for searches for natural new physics at the LHC and new assessments of the interplay between direct dark matter searches and the LHC are also considered.Comment: Proceedings of the New Physics Working Group of the 2015 Les Houches Workshop, Physics at TeV Colliders, Les Houches 1-19 June 2015. 197 page