Dark Matter Abundance and Electroweak Baryogenesis in the CMSSM

The Minimal Supersymmetric Standard Model has a candidate dark matter particle in its spectrum and may be able to generate the baryon asymmetry of the Universe (BAU) at the electroweak phase transition. In the Constrained MSSM, we find the area of parameter space which is allowed by accelerator and precision tests, which produces a relic dark matter abundance in the observationally favored window 0.1<Omega h^2<0.3, and where baryon plus lepton number violating processes are out of equilibrium after the electroweak phase transition.Comment: 14 pages in LaTeX, including 7 encapsulated postscript figure

Flavour Matters in Leptogenesis

We give analytic approximations to the baryon asymmetry produced by thermal leptogenesis with hierarchical right-handed neutrinos. Our calculation includes flavour-dependent washout processes and CP violation in scattering, and neglects gauge interactions and finite temperature corrections. Our approximate formulae depend upon the three CP asymmetries in the individual lepton flavours as well as on three flavour-dependent efficiency factors. We show that the commonly used expressions for the lepton asymmetry, which depend on the total CP asymmetry and one single efficiency factor, may fail to reproduce the correct lepton asymmetry in a number of cases. We illustrate the importance of using the flavour-dependent formulae in the context of a two right-handed neutrino model.Comment: Additional typos corrected (in particular, the plots and captions now agree

Leptogenesis with four gauge singlets

We consider a generic type of leptogenesis model which can successfully produce the correct value of the observed baryon number to entropy ratio. The main feature of this model is that it is a simple TeV scale model, a scale accessible in near future machines, with a minimal particle content. Both supersymmetric and non-supersymmetric versions of the model are feasible. This model also gives left-handed neutrino masses compatible with all current data from direct and indirect neutrino experiments.Comment: 13 pages, 9 PS figures, REVTe

Neutral Higgs Sector of the MSSM without RpR_p

We analyse the neutral scalar sector of the MSSM without R-parity. Our analysis is performed for a one-generation model in terms of ``basis-independent'' parameters, and includes one-loop corrections due to large yukawa couplings. We concentrate on the consequences of large $R_p$ violating masses in the soft sector, which mix the Higgses with the sleptons, because these are only constrained by their one-loop contributions to neutrino masses. We focus on the effect of $R_p$-violation on the Higgs mass and branching ratios. We find that the experimental lower bound on the lightest CP-even Higgs in this model can be lower than in the MSSM.Comment: minor changes, version to appear in journa

Integrating existing climate adaptation planning into future visions: A strategic scenario for the central Arizona–Phoenix region

Cities face a number of challenges to ensure that people’s well-being and ecosystem integrity are not only maintained but improved for current and future generations. Urban planning must account for the diverse and changing interactions among the social, ecological, and technological systems (SETS) of a city. Cities struggle with long-range approaches to explore, anticipate, and plan for sustainability and resilience—and scenario development is one way to address this need. In this paper, we present the framework for developing what we call ‘strategic’ scenarios, which are scenarios or future visions created from governance documents expressing unrealized municipal priorities and goals. While scenario approaches vary based on diverse planning and decision-making objectives, only some offer tangible, systemic representations of existing plans and goals for the future that can be explored as an assessment and planning tool for sustainability and resilience. Indeed, the strategic scenarios approach presented here (1) emphasizes multi-sectoral and interdisciplinary interventions; (2) identifies systemic conflicts, tradeoffs, and synergies among existing planning goals; and (3) incorporates as yet unrealized goals and strategies representative of urban short-term planning initiatives. We present an example strategic scenario for the Central Arizona–Phoenix metropolitan region, and discuss the utility of the strategic scenario in long-term thinking for future sustainability and resilience in urban research and practice. This approach brings together diverse—sometimes competing—strategies and offers the opportunity to explore outcomes by comparing and contrasting their implications and tradeoffs, and evaluating the resulting strategic scenario against scenarios developed through alternative, participatory approaches

FAK promotes stromal PD-L2 expression associated with poor survival in pancreatic cancer

BACKGROUND: Pancreatic Cancer is one of the most lethal cancers, with less than 8% of patients surviving 5 years following diagnosis. The last 40 years have seen only small incremental improvements in treatment options, highlighting the continued need to better define the cellular and molecular pathways contributing to therapy response and patient prognosis. METHODS: We combined CRISPR, shRNA and flow cytometry with mechanistic experiments using a Kras(G12D)p53(R172H) mouse model of pancreatic cancer and analysis of publicly available human PDAC transcriptomic datasets. RESULTS: Here, we identify that expression of the immune checkpoint, Programmed Death Ligand 2 (PD-L2), is associated with poor prognosis, tumour grade, clinical stage and molecular subtype in patients with Pancreatic Ductal Adenocarcinoma (PDAC). We further show that PD-L2 is predominantly expressed in the stroma and, using an orthotopic murine model of PDAC, identify cancer cell-intrinsic Focal Adhesion Kinase (FAK) signalling as a regulator of PD-L2 stromal expression. Mechanistically, we find that FAK regulates interleukin-6, which can act in concert with interleukin-4 secreted by CD4 T-cells to drive elevated expression of PD-L2 on tumour-associated macrophages, dendritic cells and endothelial cells. CONCLUSIONS: These findings identify further complex heterocellular signalling networks contributing to FAK-mediated immune suppression in pancreatic cancer

Flavour Issues in Leptogenesis

We study the impact of flavour in thermal leptogenesis, including the quantum oscillations of the asymmetries in lepton flavour space. In the Boltzmann equations we find different numerical factors and additional terms which can affect the results significantly. The upper bound on the CP asymmetry in a specific flavour is weaker than the bound on the sum. This suggests that -- when flavour dynamics is included -- there is no model-independent limit on the light neutrino mass scale,and that the lower bound on the reheat temperature is relaxed by a factor ~ (3 - 10).Comment: 19 pages, corrected equations for flavour oscillation

Near-wall modeling of forests for atmosphere boundary layers using lattice Boltzmann method on GPU

In this paper, the simulation and modeling of the turbulent atmospheric boundary layers (ABLs) in the presence of forests are studied using a lattice Boltzmann method with large eddy simulation, which was implemented in the open-source program GASCANS with the use of Graphic Processing Units (GPU). A method of modeling forests in the form of body forces injected near the wall is revisited, while the effects of leaf area density (LAD) on the model accuracy is further addressed. Since a uniform cell size is applied throughout the computational domain, the wall-normal height of the near-wall cells is very large, theoretically requiring a wall function to model the boundary layer. However, the wall function is disregarded here when the forest is modeled. This approximation is validated based on the comparison with previous experimental and numerical data. It concludes that for the ABL conditions specified in this study as well as a large body of literature, the forest forces overwhelm the wall friction so that the modeling of the latter effect is trivial. Constant and varying LAD profiles across the forest zone are defined with the same total leaf area despite the varying one being studied previously. It is found that the two LAD profiles provide consistent predictions. The present forest modeling can therefore be simplified with the use of the constant LAD without degrading the model accuracy remarkably