Using A Nameserver to Enhance Control System Efficiency

The Thomas Jefferson National Accelerator Facility (Jefferson Lab) control system uses a nameserver to reduce system response time and to minimize the impact of client name resolution on front-end computers. The control system is based on the Experimental Physics and Industrial Control System (EPICS), which uses name-based broadcasts to initiate data communication. By default, when EPICS process variables (PV) are requested by client applications, all front-end computers receive the broadcasts and perform name resolution processing against local channel name lists. The nameserver is used to offload the name resolution task to a single node. This processing, formerly done on all front-end computers, is now done only by the nameserver. In a control system with heavily loaded front-end computers and high peak client connection loads, a significant performance improvement is seen. This paper describes the name server in more detail, and discusses the strengths and weaknesses of making name resolution a centralized service.Comment: ICALEPCS 200

Staffing National Health Care Reform: A Role for Advanced Practice Nurses

Expanding access and coverage while containing costs can only be accomplished by getting more health care value for our money. Two facts about our current system make this seem possible. First, the currently uninsured are not costless. Providing stop-gap health care to those who lack health insurance is extremely expensive -- people without formal coverage cannot afford preventive services, delay treatment of illness and face substantial barriers to reaching appropriate providers. When they receive care, it is often degrading, usually complicated and costly, and more than occasionally too late. The cost of this uncompensated care is borne by all of us in higher prices for our own health insurance, in taxes and in the federal deficit. Moreover, this cost is not distributed evenly, and reduces our ability to determine whether the price of our own health care is fair. In addition, the need for last resort care for the uninsured locks us into continued support of aging public health facilities that are often underequipped and inefficient. The second characteristic of our current system is that the utilization of health care services is tremendously wasteful. Gaps in our knowledge as to what works and what doesn\u27t, fee-for-service payment that creates incentives to do more rather than less, lack of coordination between providers, high patient expectations and fear of malpractice litigation all predispose to overutilization. We are fascinated by expensive technology, and use it uncritically. Moreover, these influences have elevated the illness-based model of care over the health-based model. As a result, a disproportionate amount of our health care budget is devoted to the treatment of acute illness, often in institutional settings, rather than to primary, preventive and long-term community and home-based care. These observations suggest a prescription for change. Improving the cost effectiveness of health care delivery -- in particular by emphasizing preventive and primary care and adopting a more discriminating approach to the use of expensive, referral services -- can free up the resources needed to include all Americans in the health care system. This effort must be undertaken by health care providers, by communities and by government

Production and state-selective detection of ultracold, ground state RbCs molecules

Using resonance-enhanced two-photon ionization, we detect ultracold, ground-state RbCs molecules formed via photoassociation in a laser-cooled mixture of 85Rb and 133Cs atoms. We obtain extensive bound-bound excitation spectra of these molecules, which provide detailed information about their vibrational distribution, as well as spectroscopic data on the RbCs ground a^3\Sigma^+ and excited (2)^3\Sigma^+, (1)^1\Pi states. Analysis of this data allows us to predict strong transitions from observed excited levels to the absolute vibronic ground state of RbCs, potentially allowing the production of stable, ultracold polar molecules at rates as large as 10^7 s^{-1}

Staffing National Health Care Reform: A Role for Advanced Practice Nurses

Expanding access and coverage while containing costs can only be accomplished by getting more health care value for our money. Two facts about our current system make this seem possible. First, the currently uninsured are not costless. Providing stop-gap health care to those who lack health insurance is extremely expensive -- people without formal coverage cannot afford preventive services, delay treatment of illness and face substantial barriers to reaching appropriate providers. When they receive care, it is often degrading, usually complicated and costly, and more than occasionally too late. The cost of this uncompensated care is borne by all of us in higher prices for our own health insurance, in taxes and in the federal deficit. Moreover, this cost is not distributed evenly, and reduces our ability to determine whether the price of our own health care is fair. In addition, the need for last resort care for the uninsured locks us into continued support of aging public health facilities that are often underequipped and inefficient. The second characteristic of our current system is that the utilization of health care services is tremendously wasteful. Gaps in our knowledge as to what works and what doesn\u27t, fee-for-service payment that creates incentives to do more rather than less, lack of coordination between providers, high patient expectations and fear of malpractice litigation all predispose to overutilization. We are fascinated by expensive technology, and use it uncritically. Moreover, these influences have elevated the illness-based model of care over the health-based model. As a result, a disproportionate amount of our health care budget is devoted to the treatment of acute illness, often in institutional settings, rather than to primary, preventive and long-term community and home-based care. These observations suggest a prescription for change. Improving the cost effectiveness of health care delivery -- in particular by emphasizing preventive and primary care and adopting a more discriminating approach to the use of expensive, referral services -- can free up the resources needed to include all Americans in the health care system. This effort must be undertaken by health care providers, by communities and by government

Note and Comment

A Spurious Law Course; Railroad Taxation in Michigan and Wisconsin; Surgical Operation on Minor Without Consent of Parent; The Power of Municipal Corporations to Grant Exclusive Privileges; Inheritance Taxes and the Right to Transfer and Inherit Property; The Sovereign Power of a State to Prevent Election Frauds; Original Jurisdiction of Supreme Court in Election Cases

Triviality and the (Supersymmetric) See-Saw

For the D=5 Majorana neutrino mass operator to have a see-saw ultraviolet completion that is viable up to the Planck scale, the see-saw scale is bounded above due to triviality limits on the see-saw couplings. For supersymmetric see-saw models, with realistic neutrino mass textures, we compare constraints on the see-saw scale from triviality bounds, with those arising from experimental limits on induced charged-lepton flavour violation, for both the CMSSM and for models with split supersymmetry.Comment: 27 pages, 7 figures, references adde

Evidence for multiple mechanisms underlying surface electric-field noise in ion traps

Electric-field noise from ion-trap electrode surfaces can limit the fidelity of multiqubit entangling operations in trapped-ion quantum information processors and can give rise to systematic errors in trapped-ion optical clocks. The underlying mechanism for this noise is unknown, but it has been shown that the noise amplitude can be reduced by energetic ion bombardment, or “ion milling,” of the trap electrode surfaces. Using a single trapped ⁸⁸Sr⁺ ion as a sensor, we investigate the temperature dependence of this noise both before and after ex situ ion milling of the trap electrodes. Making measurements over a trap electrode temperature range of 4 K to 295 K in both sputtered niobium and electroplated gold traps, we see a marked change in the temperature scaling of the electric-field noise after ion milling: power-law behavior in untreated surfaces is transformed to Arrhenius behavior after treatment. The temperature scaling becomes material-dependent after treatment as well, strongly suggesting that different noise mechanisms are at work before and after ion milling. To constrain potential noise mechanisms, we measure the frequency dependence of the electric-field noise, as well as its dependence on ion-electrode distance, for niobium traps at room temperature both before and after ion milling. These scalings are unchanged by ion milling.National Science Foundation (U.S.) (Award DMR-14-19807)United States. Air Force Office of Scientific Research (Contract FA8721-05-C-0002

The Cool ISM in S0 Galaxies. I. A Survey of Molecular Gas

Lenticular galaxies remain remarkably mysterious as a class. Observations to date have not led to any broad consensus about their origins, properties and evolution, though they are often thought to have formed in one big burst of star formation early in the history of the Universe, and to have evolved relatively passively since then. In that picture, current theory predicts that stellar evolution returns substantial quantities of gas to the interstellar medium; most is ejected from the galaxy, but significant amounts of cool gas might be retained. Past searches for that material, though, have provided unclear results. We present results from a survey of molecular gas in a volume-limited sample of field S0 galaxies, selected from the Nearby Galaxies Catalog. CO emission is detected from 78 percent of the sample galaxies. We find that the molecular gas is almost always located inside the central few kiloparses of a lenticular galaxy, meaning that in general it is more centrally concentrated than in spirals. We combine our data with HI observations from the literature to determine the total masses of cool and cold gas. Curiously, we find that, across a wide range of luminosity, the most gas rich galaxies have about 10 percent of the total amount of gas ever returned by their stars. That result is difficult to understand within the context of either monolithic or hierarchical models of evolution of the interstellar medium.Comment: 26 pages of text, 15 pages of tables, 10 figures. Accepted for publication in the Astrophysical Journa

Molecular regimes in ultracold Fermi gases

The use of Feshbach resonances for tuning the interparticle interaction in ultracold Fermi gases has led to remarkable developments, in particular to the creation and Bose-Einstein condensation of weakly bound diatomic molecules of fermionic atoms. These are the largest diatomic molecules obtained so far, with a size of the order of thousands of angstroms. They represent novel composite bosons, which exhibit features of Fermi statistics at short intermolecular distances. Being highly excited, these molecules are remarkably stable with respect to collisional relaxation, which is a consequence of the Pauli exclusion principle for identical fermionic atoms. The purpose of this review is to introduce theoretical approaches and describe the physics of molecular regimes in two-component Fermi gases and Fermi-Fermi mixtures, focusing attention on quantum statistical effects.Comment: Chapter of the book: "Cold Molecules: Theory, Experiment, Applications" edited by R. V. Krems, B. Friedrich and W. C. Stwalley (publication expected in March 2009