Strange particles have been a very important observable in the search for a deconfined state of strongly interacting matter, the quark–gluon plasma (QGP), which is expected to be formed in ...ultra-relativistic heavy ion collisions. We review the main experimental observations made at the Super Proton Synchrotron (SPS) at CERN, Geneva, and at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). The large amount of recently collected data allows for a comprehensive study of strangeness production as a function of energy and system size. We review results on yields, transverse mass and rapidity spectra, as well as elliptic flow. The measurements are interpreted in the context of various theoretical concepts and their implications are discussed. Of particular interest is the question whether strange particles are in any way sensitive to a partonic phase. Finally, a compilation of experimental data is provided.
Objective Stress and sexuality are relevant factors in everyday life that affect health and well-being. Associations between stress and sexuality, however, have not yet been sufficiently investigated ...in daily life. This ecological momentary assessment study examined the bidirectional interaction between psychobiological stress markers and sexual desire/arousal in everyday life. Methods Heterosexual healthy women (n = 32) and men (n = 31) (M = 24.51 years old, SD = 2.99, range: 19–32 years old) in a romantic relationship entered data on subjective stress and sexual desire and arousal using an iPod seven times a day and collected saliva samples six times per day for 14 consecutive days. Saliva samples were analyzed for cortisol. Due to the nested data structure, multilevel models were calculated. Results Higher subjective stress was associated with lower sexual desire (UC = −0.09, p < 0.001, Pseudo R2 = 0.015) and sexual arousal (UC = −0.07, p < 0.001, Pseudo R2 = 0.011) at the same time point. Higher cortisol levels in women were associated with lower sexual desire than in men (UC = −0.122, p = 0.016, Pseudo R2 = 0.005). Higher sexual desire was associated with lower subjective stress (UC = −0.06, p = 0.011, Pseudo R2 = 0.014). No significant effects were found from one time point to the next. Conclusion Our findings suggest that individuals with low sexual desire and arousal may benefit from interventions with a stress reducing effect. Future studies should investigate possible beneficial effects of such interventions in healthy samples as well as in a clinical context.
We established a new limited sampling strategy to assess CYP3A activity and evaluated the time course of reversible (voriconazole) and irreversible (ritonavir) CYP3A inhibition. In this randomized ...trial, two groups, each with eight healthy participants, received CYP3A inhibitors voriconazole or ritonavir orally for 9 days, with 3 mg midazolam (MDZ) administered before the inhibitor treatment, on days 1, 2, 3, 5, 8, and 9 during inhibitor treatment, and on days 10, 11, and 12 (3 days) after discontinuation. Plasma MDZ area under the curve (AUC) between 2 and 4 h after oral administration in the form of a solution strongly correlated with MDZ clearance. Using this parameter, maximum inhibition of voriconazole and ritonavir was calculated to have occurred only 48 h after starting of the inhibitor (percentage of baseline MDZ clearance, voriconazole: 10.6%; ritonavir: 8.4%). Recovery of CYP3A activity occurred with a half‐life of 24 h after voriconazole, whereas ritonavir inhibition was still strong 3 days after discontinuation. These findings underscore the substantial and gradual alterations in dose requirements in the first days of and after such combination therapies.
Clinical Pharmacology & Therapeutics (2011); 90 5, 666–673. doi:10.1038/clpt.2011.164
We study the mechanism and probability of in-medium hadronization in the deconfined medium produced in heavy-ion collisions at RHIC and LHC. We show the likelihood of color-neutral objects to be ...formed inside the partonic fireball and the probability of these states to escape the medium with reduced interaction strength and energy loss. We will suggest specific measurements that are sensitive to the early degrees of freedom and show predictions for these measurements at RHIC and the LHC.
Hadronic resonances can play a pivotal role in providing experimental evidence for partial chiral symmetry restoration in the deconfined quark–gluon phase produced at RHIC and the LHC. Their ...lifetimes, which are comparable to the lifetime of the partonic plasma phase, make them an invaluable tool to study medium modifications to the resonant state due to the chiral transition. In this Letter we show that the heavier, but still abundant, light and strange quark resonances K∗, ϕ, Δ and Λ∗ have large probability to be produced well within the plasma phase due to their short formation times. We demonstrate that, under particular kinematic conditions, these resonances can be formed and will decay inside the partonic state, but still carry sufficient momentum to not interact strongly with the hadronic medium after the QCD phase transition. Thus, K∗, ϕ, Δ and Λ∗ should exhibit the characteristic property modifications which can be attributed to chiral symmetry restoration, such as mass shifts, width broadening or branching ratio modifications.
We present studies that show how multi-parton interaction and color reconnection affect the hadro-chemistry in proton-proton (pp) collisions with special focus on the production of resonances using ...the pythia8 event generator. We find that color reconnection suppresses the relative production of meson resonances such as ρ0 and K*, providing an alternative explanation for the K*/K decrease observed in proton-proton collisions as a function of multiplicity by the ALICE collaboration. Detailed studies of the underlying mechanism causing meson resonance suppression indicate that color reconnection leads to shorter, less energetic strings whose fragmentation is less likely to produce more massive hadrons for a given quark content, therefore reducing ratios such as K*/K and ρ0/π in high-multiplicity pp collisions. In addition, we have also studied the effects of allowing string junctions to form and found that these may also contribute to resonance suppression.
The aim of this paper is to understand resonance production (and more generally particle production) for different collision systems, namely proton-proton (pp), proton-nucleus (pA), and ...nucleus-nucleus (AA) scattering at the LHC. We will investigate in particular particle yields and ratios versus multiplicity, using the same multiplicity definition for the three different systems, in order to analyse in a compact way the evolution of particle production with the system size and the origin of a very different system size dependence of the different particles.
Autosomal recessive limb-girdle muscular dystrophy type 2G (LGMD2G) is an adult-onset myopathy characterized by distal lower limb weakness, calf hypertrophy and progressive decline in ambulation. The ...disease is caused by mutations in Tcap, a z-disc protein of skeletal muscle, although the precise mechanisms resulting in clinical symptoms are unknown. To provide a model for preclinical trials and for mechanistic studies, we generated knockout (KO) mice carrying a null mutation in the Tcap gene. Here we present the first report of a Tcap KO mouse model for LGMD2G and the results of an investigation into the effects of Tcap deficiency on skeletal muscle function in 4- and 12-month-old mice. Muscle histology of Tcap-null mice revealed abnormal myofiber size variation with central nucleation, similar to findings in the muscles of LGMD2G patients. An analysis of a Tcap binding protein, myostatin, showed that deletion of Tcap was accompanied by increased protein levels of myostatin. Our Tcap-null mice exhibited a decline in the ability to maintain balance on a rotating rod, relative to wild-type controls. No differences were detected in force or fatigue assays of isolated extensor digitorum longus (EDL) and soleus (SOL) muscles. Finally, a mechanical investigation of EDL and SOL indicated an increase in muscle stiffness in KO animals. We are the first to establish a viable KO mouse model of Tcap deficiency and our model mice demonstrate a dystrophic phenotype comparable to humans with LGMD2G.
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