Post cardiac surgery sternal wound sepsis burden, risk factors and outcomes at Red Cross War Memorial Children’s Hospital, Cape Town, South Africa: A five-year experience

Purpose: Sternal wound infection (SWI) is associated with significant morbidity and mortality in post-operative cardiac patients. We aimed to describe the burden, risk factors and outcomes of SWI in post-operative paediatric cardiac patients at a tertiary children’s hospital.Methods: We conducted a retrospective record review of cardiac surgeries via median sternotomy over a 5-year period to identify cases of SWI.Results: Between 2011 and 2016, 1 319 patients underwent median sternotomy. Thirty four (2.6%) patients developed SWI; 18 (13%) patients developed deep sternal wound infection (DSWI), and 16 (12%) developed superficial sternal wound infections (SSWI). Twenty two (16%) of SWIs were apparent within a week postsurgery before discharge, and the remaining were readmitted post-discharge. Seven (0.5%) patients died from complications.Conclusion: Significant morbidity was associated with SWI. Furthermore, with a mortality rate of 20% in the case of DSWI, we strongly support quality improvement procedures such as the Sternal Wound Prevention Bundle (SWPB) that was introduced in late 2014. However, the rate of SWI implies that ongoing monitoring and evaluation of the SWPB is necessary and more stringent adherence to the protocol may result in better outcomes

A Complete Theory of Grand Unification in Five Dimensions

A fully realistic unified theory is constructed, with SU(5) gauge symmetry and supersymmetry both broken by boundary conditions in a fifth dimension. Despite the local explicit breaking of SU(5) at a boundary of the dimension, the large size of the extra dimension allows precise predictions for gauge coupling unification, alpha_s(M_Z) = 0.118 \pm 0.003, and for Yukawa coupling unification, m_b(M_Z) = 3.3 \pm 0.2 GeV. A complete understanding of the MSSM Higgs sector is given; with explanations for why the Higgs triplets are heavy, why the Higgs doublets are protected from a large tree-level mass, and why the mu and B parameters are naturally generated to be of order the SUSY breaking scale. All sources of d=4,5 proton decay are forbidden, while a new origin for d=6 proton decay is found to be important. Several aspects of flavor follow from an essentially unique choice of matter location in the fifth dimension: only the third generation has an SU(5) mass relation, and the lighter two generations have small mixings with the heaviest generation. The entire superpartner spectrum is predicted in terms of only two free parameters. The squark and slepton masses are determined by their location in the fifth dimension, allowing a significant experimental test of the detailed structure of the extra dimension. Lepton flavor violation is found to be generically large in higher dimensional unified theories with high mediation scales of SUSY breaking. In our theory this forces a common location for all three neutrinos, predicting large neutrino mixing angles. Rates for mu -> e gamma, mu -> e e e, mu -> e conversion and tau -> mu gamma are larger in our theory than in conventional 4D supersymmetric GUTs. Proposed experiments probing mu -> e transitions will probe the entire interesting parameter space of our theory.Comment: 51 pages, late

Application of the pMHC array to characterise tumour antigen specific T cell populations in leukaemia patients at disease diagnosis

Immunotherapy treatments for cancer are becoming increasingly successful, however to further improve our understanding of the T-cell recognition involved in effective responses and to encourage moves towards the development of personalised treatments for leukaemia immunotherapy, precise antigenic targets in individual patients have been identified. Cellular arrays using peptide-MHC (pMHC) tetramers allow the simultaneous detection of different antigen specific T-cell populations naturally circulating in patients and normal donors. We have developed the pMHC array to detect CD8+ T-cell populations in leukaemia patients that recognise epitopes within viral antigens (cytomegalovirus (CMV) and influenza (Flu)) and leukaemia antigens (including Per Arnt Sim domain 1 (PASD1), MelanA, Wilms’ Tumour (WT1) and tyrosinase). We show that the pMHC array is at least as sensitive as flow cytometry and has the potential to rapidly identify more than 40 specific T-cell populations in a small sample of T-cells (0.8–1.4 x 106). Fourteen of the twenty-six acute myeloid leukaemia (AML) patients analysed had T cells that recognised tumour antigen epitopes, and eight of these recognised PASD1 epitopes. Other tumour epitopes recognised were MelanA (n = 3), tyrosinase (n = 3) and WT1126-134 (n = 1). One of the seven acute lymphocytic leukaemia (ALL) patients analysed had T cells that recognised the MUC1950-958 epitope. In the future the pMHC array may be used provide point of care T-cell analyses, predict patient response to conventional therapy and direct personalised immunotherapy for patients

Charge and Isospin Fluctuations in High Energy pp-Collisions

Charge and isospin event-by-event fluctuations in high-energy pp-collisions are predicted within the Unitary Eikonal Model, in particular the fluctuation patterns of the ratios of charged-to-charged and neutral-to-charged pions. These fluctuations are found to be sensitive to the presence of unstable resonances, such as $\rho$ and $\omega$ mesons. We predict that the charge-fluctuation observable $D_{UEM}$ should be restricted to the interval $8/3\le D_{UEM}\le 4$ depending on the $\rho /\pi$ production ratio. Also, the isospin fluctuations of the DCC-type of the ratio of neutral-to-charged pions are suppressed if pions are produced together with $\rho$ mesons.Comment: Latex, 5 pages, no figures. To appear in the proceedings of 9th Adriatic Meeting, Dubrovnik, Croatia, 4 - 14 September 2003. Added reference into reference no.

Democratic (S)fermions and Lepton Flavor Violation

The democratic approach to account for fermion masses and mixing is known to be successful not only in the quark sector but also in the lepton sector. Here we extend this ansatz to supersymmetric standard models, in which the K\"ahler potential obeys underlying S_3 flavor symmetries. The requirement of neutrino bi-large mixing angles constrains the form of the K\"ahler potential for left-handed lepton multiplets. We find that right-handed sleptons can have non-degenerate masses and flavor mixing, while left-handed sleptons are argued to have universal and hence flavor-blind masses. This mass pattern is testable in future collider experiments when superparticle masses will be measured precisely. Lepton flavor violation arises in this scenario. In particular, \mu \to e \gamma is expected to be observed in a planning future experiment if supersymmetry breaking scale is close to the weak scale.Comment: 22 pages, 2 figure

Slepton Oscillation at Large Hadron Collider

Measurement of Lepton-Flavor Violation (LFV) in the minimal SUSY Standard Model (MSSM) at Large Hadron Collider (LHC) is studied based on a realistic simulation. We consider the LFV decay of the second-lightest neutralino, $\tilde{\chi}^0_2 \to \tilde{l} l' \to l l' \tilde{\chi}^0_1$, in the case where the flavor mixing exists in the right-handed sleptons. We scan the parameter space of the minimal supergravity model (MSUGRA) and a more generic model in which we take the Higgsino mass $\mu$ as a free parameter. We find that the possibility of observing LFV at LHC is higher if $\mu$ is smaller than the MSUGRA prediction; the LFV search at LHC can cover the parameter range where the $\mu \to e \gamma$ decay can be suppressed by the cancellation among the diagrams for this case.Comment: 29 pages, 10 figure

The influence of life history traits on the phenological response of British butterflies to climate variability since the late-19th century

Many species of plants and animals have advanced their phenology in response to climate warming in recent decades. Most of the evidence available for these shifts is based on data from the last few decades, a period coinciding with rapid climate warming. Baseline data is required to put these recent phenological changes in a long-term context. We analysed the phenological response of 51 resident British butterfly species using data from 83 500 specimens in the collections of the Natural History Museum, London, covering the period 1880–1970. Our analysis shows that only three species significantly advanced their phenology between 1880 and 1970, probably reflecting the relatively small increase in spring temperature over this period. However, the phenology of all but one of the species we analysed showed phenological sensitivity to inter-annual climate variability and a significant advancement in phenology in years in which spring or summer temperatures were warm and dry. The phenologies of butterfly species were more sensitive to weather if the butterfly species was early flying, southerly distributed, and a generalist in terms of larval diet. This observation is consistent with the hypothesis that species with greater niche breadth may be more phenologically sensitive than species with important niche constraints. Comparison of our results with post-1976 data from the UK Butterfly Monitoring Scheme show that species flying early in the year had a greater rate of phenological advancement prior to the mid-1970s. Additionally, prior to the mid-1970s, phenology was influenced by temperatures in March or April, whereas since 1976, February temperature had a stronger influence on the phenology. These results suggest that early flying species may be approaching the limits of phenological advancement in response to recent climate warming

Muon anomalous magnetic moment, lepton flavor violation, and flavor changing neutral current processes in SUSY GUT with right-handed neutrino

Motivated by the large mixing angle solutions for the atmospheric and solar neutrino anomalies, flavor changing neutral current processes and lepton flavor violating processes as well as the muon anomalous magnetic moment are analyzed in the framework of SU(5) SUSY GUT with right-handed neutrino. In order to explain realistic mass relations for quarks and leptons, we take into account effects of higher dimensional operators above the GUT scale. It is shown that the supersymmetric (SUSY) contributions to the CP violation parameter in $K^0-\bar{K}^0$ mixing, $\epsilon_K$, the $\mu \to e \gamma$ branching ratio, and the muon anomalous magnetic moment become large in a wide range of parameter space. We also investigate correlations among these quantities. Within the current experimental bound of $\text{B}(\mu \to e \gamma)$, large SUSY contributions are possible either in the muon anomalous magnetic moment or in $\epsilon_K$. In the former case, the favorable value of the recent muon anomalous magnetic moment measurement at the BNL E821 experiment can be accommodated. In the latter case, the allowed region of the Kobayashi-Maskawa phase can be different from the prediction within the Standard Model (SM) and therefore the measurements of the CP asymmetry of $B\to J/\psi K_S$ mode and $\Delta m_{B_s}$ could discriminate this case from the SM. We also show that the $\tau \to \mu \gamma$ branching ratio can be close to the current experimental upperbound and the mixing induced CP asymmetry of the radiative B decay can be enhanced in the case where the neutrino parameters correspond to the Mikheyev-Smirnov-Wolfenstein small mixing angle solution.Comment: 70 pages, 14 figure