No abstract

Existing data on the ionization of neutral atoms and molecules by proton impact are reviewed, and electron production cross-section data are collected. The three major experimental methods are discussed and possible sources of error identified. Some theoretical cross sections are discussed, and well-established methods of relating them to measured cross sections are reviewed. A mathematical equation is fitted to the weighted experimental data for each target, and these fits are adjusted to be consistent with appropriate theoretical calculations and with electron impact and photoionization data. Recommended values of total cross sections for proton-impact ionization are given.

Economists have long been interested in understanding how individuals form beliefs over the likelihood of random events such as natural disasters. One reason why natural disasters have garnered attention is the finding that economic agents appear to overreact to the occurrence of a new disaster (e.g., Slovic, Kunreuther, and White 1974;Kunreuther 1976;Kunreuther et al. 1978).1 Kahneman (2011) points to the research on natural disasters as among the earliest evidence of the judgment heuristic known as availability bias.2 Nevertheless, a large and immediate change in beliefs after a disaster could be consistent with the common Bayesian learning model (DeGroot 1970;Viscusi 1991;Davis 2004).Flooding is an example of a type of rare stochastic event where detailed information regarding the likelihood of the event is accessible, but personal experience is infrequent. In most communities in the United States, decades of historical flood 1 This finding is sometimes described as an underreaction in terms of preparedness and expectations before a disaster rather than an overreaction afterward. 2 Availability bias is described as "situations in which people assess the frequency of a class or the probability of an event by the ease with which instances or occurrences can be brought to mind" (Tversky and Kahneman 1982, 11).

Spectroscopic data and reaction rate coefficients pertinent to ozone in the mesosphere and thermosphere (altitude> 50 km) are critically surveyed. These data should be of use in modeling atmospheric infrared luminescence, measuring atmospheric ozone concentrations by remote sensing, and designing and interpreting laboratory measurements. There is a clear need for additional data on metastable ozone electronic states, additional atmospheric ozone formation channels, collision processes involving electrons and Ions, and vibrational state dependence of reaction rate coefficients.

Approximately $30 billion (2000$) has been spent on Superfund clean-ups of hazardous waste sites, and remediation efforts are incomplete at roughly half of the 1,500 Superfund sites. This study estimates the effect of Superfund clean-ups on local housing price appreciation. We compare housing price growth in the areas surrounding the first 400 hazardous waste sites to be cleaned up through the Superfund program to the areas surrounding the 290 sites that narrowly missed qualifying for these clean-ups. We cannot reject that the clean-ups had no effect on local housing price growth, nearly two decades after these sites became eligible for them. This finding is robust to a series of specification checks, including the application of a quasi-experimental regression discontinuity design based on knowledge of the selection rule. Overall, the preferred estimates suggest that the benefits of Superfund clean-ups as measured through the housing market are substantially lower than the $43 million mean cost of Superfund clean-ups.

BackgroundHome-based robotic technologies may offer the possibility of self-directed upper limb exercise after stroke as a means of increasing the intensity of rehabilitation treatment. The current literature has a paucity of robotic devices that have been tested in a home environment. The aim of this research project was to evaluate a robotic device Home-based Computer Assisted Arm Rehabilitation (hCAAR) that can be used independently at home by stroke survivors with upper limb weakness.MethodshCAAR device comprises of a joystick handle moved by the weak upper limb to perform tasks on the computer screen. The device provides assistance to the movements depending on users ability. Nineteen participants (stroke survivors with upper limb weakness) were recruited. Outcome measures performed at baseline (A0), at end of 8-weeks of hCAAR use (A1) and 1 month after end of hCAAR use (A2) were: Optotrak kinematic variables, Fugl Meyer Upper Extremity motor subscale (FM-UE), Action Research Arm Test (ARAT), Medical Research Council (MRC) and Modified Ashworth Scale (MAS), Chedoke Arm and Hand Activity Inventory (CAHAI) and ABILHAND.ResultsTwo participants were unable to use hCAAR: one due to severe paresis and the other due to personal problems. The remaining 17 participants were able to use the device independently in their home setting. No serious adverse events were reported. The median usage time was 433 minutes (IQR 250 – 791 min). A statistically significant improvement was observed in the kinematic and clinical outcomes at A1. The median gain in the scores at A1 were by: movement time 19%, path length 15% and jerk 19%, FM-UE 1 point, total MAS 1.5 point, total MRC 2 points, ARAT 3 points, CAHAI 5.5 points and ABILHAND 3 points. Three participants showed clinically significant improvement in all the clinical outcomes.ConclusionsThe hCAAR feasibility study is the first clinical study of its kind reported in the current literature; in this study, 17 participants used the robotic device independently for eight weeks in their own homes with minimal supervision from healthcare professionals. Statistically significant improvements were observed in the kinematic and clinical outcomes in the study.Electronic supplementary materialThe online version of this article (doi:10.1186/1743-0003-11-163) contains supplementary material, which is available to authorized users.

A compilation is provided of absolute total photoabsorption and partial-channel photoionization cross sections for the valence shells of selected molecules, including diatomics (H 2 , N 2 , O 2 , CO, NO) and triatomics (C0 2 , N 2 0), simple hydrides (H 2 0, NH 3 , CH 4), hydrogen halides (HF, HCI, HBr, HI), sulfur compounds (H 2 S, CS 2 , OCS, S02' SF 6), and chlorine compounds (CI 2 , CCI 4). The partial-channel cross sections presented refer to production of the individual electronic states of molecular ions and also to production of parent and specific fragment ions, as functions of incident photon energy, typically from ,...,20 to 100 eV. Total photoabsorption cross sections above the first ionization threshold are reported from conventional optical measurements obtained using line and continuum sources and from "equivalent-photon" dipole (e,e) electron scattering experiments. Partial photoionization cross sections for production of electronic states of molecular ions are obtained from photoelectron spectroscopy and from dipole (e,2e) coincidence measurements. Photoionization mass spectrometry and dipole (e, e + ion) coincidence studies provide measurements of partial cross sections for ionic photofragmentation (i.e., dissociative photoionization). Photoelectron anisotropy factors, which together with electronic partial cross sections provide cross sections differential in photon energy and in ejection angle, are also reported. There is generally good agreement between cross sections measured by the physically distinct optical and dipole electron-impact methods. The cross sections and anisotropy factors also compare favorably with selected ab initio and model potential (X-alpha) calculations which provide a basis for interpretation of the measurements.

Approximately $30 billion (2000$) has been spent on Superfund clean-ups of hazardous waste sites, and remediation efforts are incomplete at roughly half of the 1,500 Superfund sites. This study estimates the effect of Superfund clean-ups on local housing price appreciation. We compare housing price growth in the areas surrounding the first 400 hazardous waste sites to be cleaned up through the Superfiind program to the areas surrounding the 290 sites that narrowly missed qualifying for these clean-ups. We cannot reject that the clean-ups had no effect on local housing price growth, nearly two decades after these sites became eligible for them. This finding is robust to a series of specification checks, including the application of a quasi-experimental regression discontinuity design based on knowledge of the selection rule.Overall, the preferred estimates suggest that the benefits of Superfund clean-ups as measured through the housing market are substantially lower than the $43 million mean cost of Superfund cleanups.