Simultaneous Determination of Neutron-Induced Fission and Radiative Capture Cross Sections from Decay Probabilities Obtained with a Surrogate Reaction.

Reliable neutron-induced-reaction cross sections of unstable nuclei are essential for nuclear astrophysics and applications but their direct measurement is often impossible. The surrogate-reaction method is one of the most promising alternatives to access these cross sections. In this work, we successfully applied the surrogate-reaction method to infer for the first time both the neutron-induced fission and radiative capture cross sections of ^{239}Pu in a consistent manner from a single measurement. This was achieved by combining simultaneously measured fission and γ-emission probabilities for the ^{240}Pu(^{4}He,^{4}He^{'}) surrogate reaction with a calculation of the angular-momentum and parity distributions populated in this reaction. While other experiments measure the probabilities for some selected γ-ray transitions, we measure the γ-emission probability. This enlarges the applicability of the surrogate-reaction method.

The Neutrons for Science Facility at SPIRAL-2.

The neutrons for science (NFS) facility is a component of SPIRAL-2, the new superconducting linear accelerator built at GANIL in Caen (France). The proton and deuteron beams delivered by the accelerator will allow producing intense neutron fields in the 100 keV-40 MeV energy range. Continuous and quasi-mono-kinetic energy spectra, respectively, will be available at NFS, produced by the interaction of a deuteron beam on a thick Be converter and by the 7Li(p,n) reaction on thin converter. The pulsed neutron beam, with a flux up to two orders of magnitude higher than those of other existing time-of-flight facilities, will open new opportunities of experiments in fundamental research as well as in nuclear data measurements. In addition to the neutron beam, irradiation stations for neutron-, proton- and deuteron-induced reactions will be available for cross-sections measurements and for the irradiation of electronic devices or biological cells. NFS, whose first experiment is foreseen in 2018, will be a very powerful tool for physics, fundamental research as well as applications like the transmutation of nuclear waste, design of future fission and fusion reactors, nuclear medicine or test and development of new detectors.

Measurement of a complete set of nuclides, cross sections, and kinetic energies in spallation of 238U 1A GeV with protons.

Spallation residues and fission fragments from 1A GeV 238U projectiles irradiating a liquid hydrogen target were investigated by using the fragment separator at GSI for magnetic selection of reaction products including ray-tracing, energy-loss and time-of-flight techniques. The longitudinal-momentum spectra of identified fragments were analyzed, and evaporation residues and fission fragments could be separated. For 1385 nuclides, production cross sections down to values of 10 microb with a mean accuracy of 15%, velocities in the uranium rest frame and kinetic energies were determined. In the reaction all elements from uranium to nitrogen were found, each with a large number of isotopes.

Two-proton radioactivity of 45Fe.

In an experiment at the SISSI-LISE3 facility of GANIL, the decay of the proton drip line nucleus 45Fe has been studied. Fragment-implantation events have been correlated with radioactive decay events in a 16x16 pixel silicon-strip detector. The decay-energy spectrum of 45Fe implants shows a distinct peak at (1.14+/-0.04) MeV with a half-life of T(1/2)=(4.7(+3.4)(-1.4)) ms. None of the events in this peak is in coincidence with beta particles. For a longer correlation interval, daughter decays of the two-proton daughter 43Cr can be observed after 45Fe implantation. The decay energy for 45Fe agrees nicely with several theoretical predictions for two-proton radioactivity.

Depression, heart rate variability, and acute myocardial infarction.

BACKGROUND: Clinical depression is associated with an increased risk for mortality in patients with a recent myocardial infarction (MI). Reduced heart rate variability (HRV) has been suggested as a possible explanation for this association. The purpose of this study was to determine if depression is associated with reduced HRV in patients with a recent MI. METHODS AND RESULTS: Three hundred eighty acute MI patients with depression and 424 acute MI patients without depression were recruited. All underwent 24-hour ambulatory electrocardiographic monitoring after hospital discharge. In univariate analyses, 4 indices of HRV were significantly lower in patients with depression than in patients without depression. Variables associated with HRV were then compared between patients with and without depression, and potential confounds were identified. These variables (age, sex, diabetes, and present cigarette smoking) were entered into an analysis of covariance model, followed by depression status. In the final model, all but one HRV index (high-frequency power) remained significantly lower in patients with depression than in patients without depression. CONCLUSIONS: We conclude that greater autonomic dysfunction, as reflected by decreased HRV, is a plausible mechanism linking depression to increased cardiac mortality in post-MI patients.

Psychosocial characteristics after acute myocardial infarction: the ENRICHD pilot study. Enhancing Recovery in Coronary Heart Disease.

PURPOSE: Psychosocial factors, such as emotional distress and social isolation, have been increasingly recognized as important risk factors for patients' recovery from acute myocardial infarction (AMI). This study examined age, gender, and ethnic differences in depression and general distress, social support, and health-related quality of life after AMI. METHODS: Data came from a series of 88 patients aged 62.1 +/- 14.2 years (46% female) who were hospitalized for AMI at eight different US clinical centers participating in the Enhancing Recovery in Coronary Heart Disease (ENRICHD) Pilot Study. Standardized psychometric measures were administered to assess three psychosocial domains: (1) depression and general distress (mental health functioning), (2) social support, and (3) health-related quality of life. Multivariate analysis of variance was used to examine the effects of age, gender, and ethnic differences in each of the three psychosocial domains. RESULTS: Female patients reported higher levels of depression and distress compared with male patients (P = .040). Gender differences in mental health functioning differed by age (P = .046), with the greatest differences observed among younger female patients. Older patients (P = .014) and female patients (P = .025) reported lower levels of social support compared with younger and male patients, respectively. Minority patients did not differ from nonminority patients in mental health functioning or social support, and there were no significant differences in post-AMI quality of life on the basis of age, gender, or ethnicity. CONCLUSIONS: The psychosocial risk profile after AMI may be different for male and female patients, and interventions may need to take account of each gender's specific needs.

Discovery of doubly magic 48Ni

In an experiment at the SISSI/LISE3 facility of GANIL, we used the projectile fragmentation of a primary 58Ni26+ beam at 74.5 MeV/nucleon with an average current of 3 &mgr;A on a natural nickel target to produce very neutron-deficient isotopes. In a 10-day experiment, 287 42Cr isotopes, 53 45Fe isotopes, 106 49Ni isotopes, and 4 48Ni isotopes were unambiguously identified. The doubly magic nucleus 48Ni, observed for the first time, is the most proton-rich isotope ever identified with an isospin projection T(z) = -4. It is probably the last doubly magic nucleus with "classical" shell closures accessible for present-day facilities. Its observation allows us to deduce a lower limit for the half-life of 48Ni of 0.5 &mgr;s.

Cross sections of spallation residues produced in 1A GeV 208Pb on proton reactions.

Spallation residues produced in 1 GeV per nucleon 208Pb on proton reactions have been studied using the Fragment Separator facility at GSI. Isotopic production cross sections of elements from 61Pm to 82Pb have been measured down to 0.1 mb with a high accuracy. The recoil kinetic energies of the produced fragments were also determined. The obtained cross sections agree with most of the few existing gamma-spectroscopic data. The data are compared with different intranuclear-cascade and evaporation-fission models. Drastic deviations were found for a standard code used in technical applications.

Maintenance of dietary behavior change.

Reducing dietary fat, saturated fat, and sodium and increasing intakes of dietary fiber and fruits and vegetables are important for cardiopulmonary risk reduction. Behaviorally, these dietary changes are very challenging, and in different ways. Fewer than half of U.S. adults have diets meeting recommended intakes of these constituents, and many do not see a need to align their diets with recommendations. Various nutrition education and behavioral counseling approaches have been shown to facilitate changes in fat, fiber, sodium, and fruits and vegetables, but primarily in research settings and among the highly motivated. Practice-based and interdisciplinary studies are needed to refine strategies to effect long-term dietary changes, to differentiate behavioral issues for changes involving additions versus deletions from the diet, and to elucidate the roles of sensory, psychosocial, and contextual factors in adoption and maintenance.

Comparison of preoperative characteristics of men and women undergoing coronary artery bypass grafting (the Post Coronary Artery Bypass Graft [CABG] Biobehavioral Study).

A cohort of 759 coronary artery bypass grafting (CABG) patients (269 women and 490 men) was enrolled in the prospective POST CABG Biobehavioral Study at 5 clinical centers in the United States and Canada. Sociodemographic and medical data were obtained by interview and from medical charts. Health-related quality of life and psychosocial data were ascertained preoperatively by interview and questionnaire for those patients whose condition allowed preoperative assessment and was compared among patients from hospitals enrolling both male and female patients (143 women and 267 men). Women enrolled in the Biobehavioral Study were older than men (65.4 +/- 9.0 vs 61.8 +/- 9.7 years, p < 0.001) and more likely to have a preoperative medical condition which precluded biobehavioral evaluation (47% vs 34%, p < 0.001). Women were less likely to be high school graduates (59% vs 74%, p < 0.001), were less likely to be earning > or = $25,000 per year (39% vs 69%, p < 0.001), and were married less often at the time of surgery (59% vs 85%, p < 0.001). Fewer women than men were able to perform basic self-care activities (p < 0.001) and social activities (p < 0.001). Women were also less able to perform the more demanding activities required for independent living, recreation, and maintaining a household (p < 0.001). Women were also more anxious (p = 0.01) and reported more depressive symptoms (p < 0.001) than men. These data suggest that plans for perioperative and convalescent care for women undergoing CABG should take into account their less favorable medical and psychosocial status relative to men.

Evaluation of an implantable ventricular assist system for humans with chronic refractory heart failure. Measuring quality of life.

The development of a multidimensional quality of life protocol to be used in a clinical trial of an LVAS was presented. The complexity of the new LVAS technology being evaluated added a unique dimension for HQL assessment. The rationale and procedures used in developing this protocol were described. Although we have elucidated the development of a protocol for a specific clinical trial, the principles and procedures employed are widely applicable. To summarize, these procedures are as follows: 1. Determine what quality of life domains are important to measure. This decision should be based upon the domains expected to be affected by treatment, those expected to change as a result of the natural course of the disease or condition, and those that may be affected by changes in the primary domains. 2. Once the domains are selected, identify specific measures for these domains. Where possible, the measures chosen should be standardized, well validated, and appropriate to the study population. Instrument length and mode of administration are additional considerations. 3. Consider any unique aspects of the study population or intervention and develop specific questions to address them. 4. Identify and measure important variables that may moderate or influence quality of life. 5. Test the protocol on an appropriate population for length, flow, and ease of administration. Copies of the complete HQL protocol are available by writing to: Dr. Nancy Avis, New England Research Institute, 9 Galen Street, Watertown, MA 02172.

A Veterans Administration Cooperative Study of biphasic calcium phosphate ceramic in periodontal osseous defects.

One hundred thirty-seven V.A. patients were randomized to one of three treatment groups to evaluate the efficacy of biphasic calcium phosphate (BCP) ceramic in the treatment of periodontal osseous defects. This material was tested against both autogenous bone implant and open flap curettage procedures. Baseline probing attachment level, Navy plaque index, and gingival index were recorded for all patients. These parameters were monitored for 3 years. At the end of this period, 101 patients had completed the study. Although the plaque and gingival indices steadily increased with time, there were no statistically significant differences among the treatment groups. Patients in the ceramic group had a gain in attachment level of 1.0 mm; those in the curettage group, 0.9 mm; and 0.4 mm for those in the bone implant group. Although the BCP patients had a greater gain, the difference was not statistically significant. In this veteran population, not only did BCP patients fail to outperform those in the control groups, all three treatment groups were similarly ineffective.