An approach to metal fatigue

Cumulative fatigue damage based on investigation of fatigue limit associated with crack, crack propagation rate, and stress interaction cycle in metal

Nonhypnotic low-dose etomidate for rapid correction of hypercortisolaemia in cushing's syndrome

We determined the adrenostatic potential of low-dose nonhypnotic etomidate in six patients with Cushing's syndrome (ectopic Cushing's syndrome,n=2; Cushing's disease,n=3; bilateral adrenal adenoma,n=1). Etomidate was given as a continuous infusion for 32 h in a dose of 2.5 mg/h (n=5) or 0.3 mg/kg/h (n=3), respectively. Saline was given during a control period. The responsiveness to exogenous ACTH was studied during placebo and 7 and 31 h after commencing etomidate by administration of 250 µg 1–24 ACTH i.v. Etomidate (2.5 mg/h) led to a consistent decrease in serum cortisol in all patients from a mean of 39.4±13.3 to 21.1±5.7 µg/dl after 7 h (P<0.05 compared with placebo). After 24 h cortisol was reduced further to a mean steady state concentration of 12.3±5.7 µg/dl (P<0.05). At the end of the infusion period the cortisol increase in response to ACTH was reduced but not abolished. In contrast, a dose of 0.3 mg/kg/h etomidate induced unresponsiveness of serum cortisol to exogenous ACTH within 7 h. However, sedation was observed in two out of three patients at this dose, while during etomidate in a dose of 2.5 mg/h no side effects were seen. We conclude that low-dose non-hypnotic etomidate reduces serum cortisol to within the normal range in patients with Cushing's syndrome. The possibility to dissociate the adrenostatic effect of etomidate from its hypnotic action, the absence of side effects, and the i.v. route suggest that etomidate in a dose of 0.04–0.05 mg/kg/h may become the drug of choice for rapid initial control of hypercortisolism

Optimum Frequency and Gradient for the CLIC main linac accelerating structure

Recently the CLIC study has changed the operating frequency and accelerating gradient of the main linac from 30 GHz and 150 MV/m to 12 GHz and 100 MV/m, respectively. This major change of parameters has been driven by the results from a novel main linac optimization procedure. The procedure allows the simultaneous optimization of operating frequency, accelerating gradient, and many other parameters of CLIC main linac. It takes into account both beam dynamics (BD) and high power RF constraints. BD constraints are related to ermittance growth due to short- and long-range transverse wakefields. RF constraints are related to RF breakdown and pulsed surface heating of the accelerating structure. The optimization figure of merit includes the power efficiency, measured as a ratio of luminosity to the input power, as well as a quantity proportional to total cost

Advanced flight control system study

A fly by wire flight control system architecture designed for high reliability includes spare sensor and computer elements to permit safe dispatch with failed elements, thereby reducing unscheduled maintenance. A methodology capable of demonstrating that the architecture does achieve the predicted performance characteristics consists of a hierarchy of activities ranging from analytical calculations of system reliability and formal methods of software verification to iron bird testing followed by flight evaluation. Interfacing this architecture to the Lockheed S-3A aircraft for flight test is discussed. This testbed vehicle can be expanded to support flight experiments in advanced aerodynamics, electromechanical actuators, secondary power systems, flight management, new displays, and air traffic control concepts

Instrumentation for measurement of cosmic noise at 0.75, 1.225 and 2.0 mc/s from a rocket final technical report

Amplitudes and phases of first harmonics of magnetic storm annual variation dependence on storm intensity and 11 year cycl

Characterization and control of phase fluctuations in elongated Bose-Einstein condensates

Quasi one dimensional Bose-Einstein condensates (BECs) in elongated traps exhibit significant phase fluctuations even at very low temperatures. We present recent experimental results on the dynamic transformation of phase fluctuations into density modulations during time-of-flight and show the excellent quantitative agreement with the theoretical prediction. In addition we confirm that under our experimental conditions, in the magnetic trap density modulations are strongly suppressed even when the phase fluctuates. The paper also discusses our theoretical results on control of the condensate phase by employing a time-dependent perturbation. Our results set important limitations on future applications of BEC in precision atom interferometry and atom optics, but at the same time suggest pathways to overcome these limitations.Comment: 9 pages, 7 figure

Testing the Higgs Mechanism in the Lepton Sector with multi-TeV e+e- Collisions

Multi-TeV e+e- collisions provide with a large enough sample of Higgs bosons to enable measurements of its suppressed decays. Results of a detailed study of the determination of the muon Yukawa coupling at 3 TeV, based on full detector simulation and event reconstruction, are presented. The muon Yukawa coupling can be determined with a relative accuracy of 0.04 to 0.08 for Higgs bosons masses from 120 GeV to 150 GeV, with an integrated luminosity of 5 inverse-ab. The result is not affected by overlapping two-photon background.Comment: 6 pages, 2 figures, submitted to J Phys G.: Nucl. Phy

Changing physical appearance preferences in the United Arab Emirates

Rapid economic growth in the United Arab Emirates (UAE) has impacted traditional ways of life rooted in Bedouin traditions and Islamic values. Research undertaken within the UAE suggests that a thin body-image ideal is widespread, as are abnormal eating attitudes and extreme dietary behaviours. However, this regional research has been exclusively cross-sectional, precluding conclusions about the temporal dynamics or nascence of these phenomena. This study explores changes in physical appearance preferences in the UAE over the past two decades. Interviews were undertaken with five khatabaat (marriage brokers), who were asked to report the attributes typically requested by those seeking wives, both now, and in the past. Thematic analysis of these data highlighted differences between the attributes currently deemed desirable, and those deemed desirable in the recent past. These findings are discussed in the context of the nation\u27s rapid socio-economic change, and their implications for body-image and eating-related problems. © 2014 © 2014 Taylor & Francis

High-Pressure Specific-Heat Spectroscopy At The Glass-Transition In O-Terphenyl

Measurements of the enthalpy relaxations in liquid orthoterphenyl in the supercooled state have been carried out using specific-heat spectroscopy over the frequency range from 2 Hz to 6.3 kHz, as a function of temperature and as a function of pressure. The observed α-relaxation peaks in the phase of the complex specific heat show increasing relaxation times τ with increasing pressure at constant temperature, similar to the divergence of τ when the calorimetric glass temperature Tg is approached by lowering the temperature at constant pressure. The temperature and pressure dependence of the measured mean relaxation times τ¯ near Tg are in remarkable agreement with those found by other spectroscopic methods and have been compared with an extended Vogel-Fulcher-Tammann law. However, we find different scaling when the glass transition is approached by cooling or by increasing pressure. This suggests that the assumption of a simple volume-activated process is not adequate

Microscopic theory for the light-induced anomalous Hall effect in graphene

We employ a quantum Liouville equation with relaxation to model the recently observed anomalous Hall effect in graphene irradiated by an ultrafast pulse of circularly polarized light. In the weak-field regime, we demonstrate that the Hall effect originates from an asymmetric population of photocarriers in the Dirac bands. By contrast, in the strong-field regime, the system is driven into a non-equilibrium steady state that is well-described by topologically non-trivial Floquet-Bloch bands. Here, the anomalous Hall current originates from the combination of a population imbalance in these dressed bands together with a smaller anomalous velocity contribution arising from their Berry curvature. This robust and general finding enables the simulation of electrical transport from light-induced Floquet-Bloch bands in an experimentally relevant parameter regime and creates a pathway to designing ultrafast quantum devices with Floquet-engineered transport properties