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The presence of the 125-GeV Higgs boson in the particle spectrum of the minimal supersymmetric (SUSY) standard model (MSSM) implies that the SUSY breaking scale has to be larger than . In this case some fine-tuning of the MSSM parameters is needed to get so light Higgs state. In a certain part of the parameter space of the simplest extension of the MSSM—next-to-minimal supersymmetric Standard Model (NMSSM) the restrictions on are weaker than in the MSSM. This part of the NMSSM parameter space leads to some predictions for the spectrum of the Higgs bosons which are considered in this paper. The possible manifestations of new Higgs states at the LHC experiments are also discussed. The analysis performed in this article indicates that light exotic states in the extensions of the MSSM may result in the nonstandard decays of the 125-GeV Higgs boson. [ABSTRACT FROM AUTHOR]

Background Elderly adults are more vulnerable to heat-induced illness because of dysfunctional thermoregulatory mechanisms, chronic dehydration, medications, and diseases involving the systems that regulate body temperature. We hypothesized that extensive loss of fluids in a hot and dry climate in the summer months may lead to impaired renal function in elderly patients. The aim of the study was to determine the impact of the season of admission on renal function and the development of acute kidney injury in elderly patients. Methods A retrospective observational cohort study on all patients older than 65 with creatinine level ≤ 2.0 mg/dL who were hospitalized twice (in the summer and in winter) in 2010–2011. The outcome was incidence of acute kidney injury. Results The study cohort included 1107 consecutive patients hospitalized in the summer and in the winter months. The biochemical parameters of impaired renal function were more prominent in the summer as compared to the winter months in the whole cohort of patients and especially in patients with hypertension, diabetes mellitus and heart failure, and in patients treated with thiazide diuretics, ACE-inhibitors and ARBs. The most common reason for hospitalization in patients developing AKI in the summer was febrile disease and sepsis and in the winter heart, failure. Conclusions Extensive fluids loss in a hot and dry climate in the summer months leads to mild impaired renal function in elderly patients. However, this influence is not clinically significant probably due to compensatory mechanisms for the preservation of renal function. [ABSTRACT FROM AUTHOR]

An attempt is made to explain the tiny order of magnitude of the cosmological constant in a model involving the following ingredients: supersymmetry breaking in N=1 supergravity and the multiple-point principle. We demonstrate the viability of this scenario in the minimal SUGRA model. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Nowadays, in the MSSM, the moderate values of tan β are almost excluded by the LEP II lower bound on the mass of the lightest Higgs boson. In the next-to-minimal supersymmetric standard model (NMSSM), the theoretical upper bound on it increases and reaches a maximal value in the limit of strong Yukawa coupling, where all solutions to renormalization-group equations are concentrated near the quasifixed point. For a calculation of the Higgs boson spectrum, the perturbation-theory method can be applied. We investigate the particle spectrum within the modified NMSSM, which leads to the selfconsistent solution in the limit of strong Yukawa coupling. This model allows one to get m[sub h] ∼ 125 GeV at tan β ≥ 1.9. In the model under investigation, the mass of the lightest Higgs boson does not exceed 130.5 ± 3.5 GeV. The upper bound on the mass of the lightest CP-even Higgs boson in more complicated supersymmetric models is also discussed. [ABSTRACT FROM AUTHOR]

The modified next-to-minimal supersymmetric standard model is the simplest model that is obtained as an extension of the minimal supersymmetric standard model and which is compatible with the LEP II experimental constraint on the mass of the lightest Higgs boson at tan β ∼ 1. The renormalization of Yukawa coupling constants and of the parameters of a soft breakdown of supersymmetry is investigated within this model. The possibility of unifying the Yukawa coupling constants for the b quark and the τ lepton at the Grand Unification scale M[sub X] is studied. The spectrum of particles is analyzed in the vicinity of a quasifixed point where solutions to the renormalization-group equations are concentrated at the electroweak scale. [ABSTRACT FROM AUTHOR]

Within a nonminimal supersymmetric (SuSy) model, the renormalization of trilinear coupling constants A[sub i](t) for scalar fields and of specific combinations M²[sub i](t) of the scalar-particle masses is investigated in the regime of strong Yukawa coupling. The dependence of these parameters on their initial values at the Grand Unification scale disappears as solutions to the renormalization-group equations approach infrared quasifixed points with increasing Y[sub i](0). In the vicinities of quasifixed points for &αtilde;[sub GUT] « Y[sub i](0) « 1, all solutions A[sub i](t) and M²[sub i](t) are concentrated near some straight lines or planes in the space of parameters of a soft breakdown of supersymmetry. This behavior of the solutions in question is explained by a sufficiently slow disappearance of the A[sub i] (0) and M²[sub i](0) dependence of the trilinear coupling constants and combinations of the scalar-particle masses. A method is proposed for deriving equations describing the aforementioned straight lines and planes, and the process of their formation is discussed by considering the example of exact and approximate solutions to the renormalization-group equations within a nonminimal supersymmetric standard model. [ABSTRACT FROM AUTHOR]

The constraints from LEPII on the mass of the lightest Higgs boson are such that, in the parameter space of the minimal supersymmetric standard model (MSSM), a considerable part of the region that corresponds to the scenario of an infrared fixed point is virtually ruled out by available experimental data. In a nonminimal supersymmetric standard model (NMSSM), the mass of the lightest Higgs boson takes its maximum value in the regime of strong Yukawa coupling, in which case the Yukawa coupling constants are much greater than the gauge coupling constants at the Grand Unification scale (Y[sub i](0) » &αtilde;[sub i](0)). In this limiting case, solutions to the renormalization-group equations are attracted to Hill and infrared fixed lines or surfaces in the space of Yukawa coupling constants; for Y[sub i](0) → ∞, they are concentrated in the vicinities of quasifixed points. However, this attraction is quite weak. For this reason, solutions to the renormalization-group equations are grouped near some line on the Hill surface when all Y[sub i](0) are close to unity. Approximate solutions for the Yukawa coupling constants within the NMSSM are presented. In addition, the possibility of unifying the Yukawa coupling constants for the b quark and the T lepton at the scale M[sub x] is discussed. [ABSTRACT FROM AUTHOR]

A theoretical analysis of solutions of renormalization group equations in the minimal supersymmetric standard model, which lead to a quasi-fixed point has shown that the mass of the lightest Higgs boson in these models does not exceed 94±5 GeV. This implies that a considerable part of the parameter space in the minimal supersymmetric model is in fact eliminated by existing LEPII experimental data. In the nonminimal supersymmetric standard model the upper bound on the mass of the lightest Higgs boson reaches its maximum in the strong Yukawa coupling regime when the Yukawa constants are substantially greater than the gauge constants on the grand unification scale. In the present paper the particle spectrum is studied using the simplest modification of the nonminimal supersymmetric standard model which gives a self-consistent solution in this region of parameter space. This model can give m[sub h]∼125 GeV even for comparatively low values of tan β≥1.9. The spectrum of Higgs bosons and neutralinos is analyzed using the method of diagonalizing mass matrices proposed earlier. In this model the mass of the lightest Higgs boson does not exceed 130.5±3.5 GeV. © 2000 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]