ALICE is a general-purpose heavy-ion experiment designed to study the physics of strongly interacting matter and the quark–gluon plasma in nucleus–nucleus collisions at the LHC. It currently involves more than 900 physicists and senior engineers, from both the nuclear and high-energy physics sectors, from over 90 institutions in about 30 countries.The ALICE detector is designed to cope with the highest particle multiplicities above those anticipated for Pb–Pb collisions (dNch/dy up to 8000) and it will be operational at the start-up of the LHC. In addition to heavy systems, the ALICE Collaboration will study collisions of lower-mass ions, which are a means of varying the energy density, and protons (both pp and pA), which primarily provide reference data for the nucleus–nucleus collisions. In addition, the pp data will allow for a number of genuine pp physics studies.The detailed design of the different detector systems has been laid down in a number of Technical Design Reports issued between mid-1998 and the end of 2004. The experiment is currently under construction and will be ready for data taking with both proton and heavy-ion beams at the start-up of the LHC.Since the comprehensive information on detector and physics performance was last published in the ALICE Technical Proposal in 1996, the detector, as well as simulation, reconstruction and analysis software have undergone significant development. The Physics Performance Report (PPR) provides an updated and comprehensive summary of the performance of the various ALICE subsystems, including updates to the Technical Design Reports, as appropriate.The PPR is divided into two volumes. Volume I, published in 2004 (CERN/LHCC 2003-049, ALICE Collaboration 2004 J. Phys. G: Nucl. Part. Phys. 30 1517–1763), contains in four chapters a short theoretical overview and an extensive reference list concerning the physics topics of interest to ALICE, the experimental conditions at the LHC, a short summary and update of the subsystem designs, and a description of the offline framework and Monte Carlo event generators.The present volume, Volume II, contains the majority of the information relevant to the physics performance in proton–proton, proton–nucleus, and nucleus–nucleus collisions. Following an introductory overview, Chapter 5 describes the combined detector performance and the event reconstruction procedures, based on detailed simulations of the individual subsystems. Chapter 6 describes the analysis and physics reach for a representative sample of physics observables, from global event characteristics to hard processes.
The electroencephalographic effects of two intravenous sedative/hypnotic drugs, propofol and thiopental, were studied at three stable blood concentrations in 52 normal healthy volunteers. The higher concentration resulted in unresponsiveness (lack of response to auditory/tactile stimuli) in all subjects. This report describes the strong frontal-central rhythms apparent in this state using a quantitative description of oscillatory systems underlying the rhythm. These rhythms occur when sedative drug concentrations are greater than those producing the well-described increase in broadband β-power associated with many sedative drugs. Propofol induces rhythms in the α-range, while thiopental produces rhythms in the β-range. Quasistationary for a period of about 1 h, these rhythms exceed the baseline α-rhythm in power. By their resonant nature, these propofol-induced rhythms are analogous to ‘the classic α-rhythm’, but quantitative characteristics of the underlying oscillatory systems are different. Baseline properties of the oscillatory system underlying the initial resting α-rhythm recover completely as drug concentration decays to negligible values.
At equal sedation, propofol produces the same degree of memory impairment as midazolam. Thiopental has mild memory effects whereas fentanyl has none. Ondansetron alone has no sedative or amnesic effects.
Midazolam causes dose-related changes in rCBF in brain regions associated with the normal functioning of arousal, attention, and memory.
Propofol has a greater amnesic effect than thiopental. In this study we tested whether different brain regions were affected by propofol and thiopental at similar drug effects. Changes in regional cerebral blood flow (rCBF) were identified by using SPM99 analysis of images obtained with positron emission tomography with (15)O water. Ten right-handed male volunteers (age, 35 +/- 10 yr; weight, 74.1 +/- 7.5 kg; mean +/- sd) were randomized to receive thiopental (n = 4) or propofol (n = 6) to target sedative and hypnotic concentrations with bispectral index (BIS) monitoring. Four positron emission tomography images were obtained during various tasks at baseline and with sedative and hypnotic effects. Two participants receiving propofol were unresponsive at sedative concentrations and were not included in the final analyses. Median serum concentrations were 1.2 and 2.7 microg/mL for sedative and hypnotic propofol effects, respectively. Similarly, thiopental concentrations were 4.8 and 10.6 microg/mL. BIS decreased similarly in both groups. The pattern of rCBF change was markedly different for propofol and thiopental. Propofol decreased rCBF in the anterior (right-sided during sedation) brain regions, whereas thiopental decreased rCBF primarily in the cerebellar and posterior brain regions. At similar levels of drug effect, propofol and thiopental affect different regions of the brain. These differences may help to identify the loci of action for the nonsedative effects of propofol, such as amnesia.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.