Positron-molecule bound states and positive ion production

The interaction was studied of low energy positrons with large molecules such as alkanes. These data provide evidencce for the existence of long lived resonances and bound states of positrons with neutral molecules. The formation process and the nature of these resonances are discussed. The positive ions produced when a positron annihilates with an electron in one of these resonances were observed and this positive ion formation process is discussed. A review is presented of the current state of the understanding of these positron-molecule resonances and the resulting positive ion formation. A number of outstanding issues in this area is also discussed

Will Churches Respond to the Call? Religion, Civic Responsibility, and Social Service

Despite national calls for churches to become more involved in social service, many churches may not be willing or able to respond. Drawing on sociological theory, previous research, and interviews with pastors and parish social ministers from Catholic congregations in a large, urban city in Texas, we examine key factors linked to church-based social service efforts. Particulara ttention is given to church leadership,r ace/ethnicity,o rganizational characteristics, social and political networks, and the intersection of these factors in affecting service provision and advocacy. We then discuss the likely impacts of policies calling for religious organizations to increase their social service activities

Spectroscopy from 2 to 200 keV

The astrophysical processes responsible for line and continuum emission in the spectra range 2 keV to 200 keV are examined from the viewpoint of designing a spectrometer which would operate in this regime. Phenomena considered include fluorescent line radiation in X-ray binaries, magnetically shifted iron lines and cyclotron emission from neutron star surfaces, line emission from cosmically abundant elements in thermal plasmas, and nuclear deexcitation lines in fresh nucleosynthetically produced matter. An instrument consisting of a approximately 10 sq cm array of planar germanium detectors surrounded by a large sodium-iodide anticoincidence shield is described and projected background rates and sensitivities are considered. A sample observing program for a two-day shuttle-based mission is included as an example of the wide range of scientific questions which could be addressed by such an instrument

Inequality and Procedural Justice in Social Dilemmas

This study investigates the influence of resource inequality and the fairness of the allocation procedure of unequal resources on cooperative behavior in social dilemmas. We propose a simple formal behavioral model that incorporates conflicting selfish and social motivations. This model allows us to predict how inequality influences cooperative behavior. Allocation of resources is manipulated by three treatments that vary in terms of procedural justice: allocating resources randomly, based on merit, and based on ascription. As predicted, procedural justice influences cooperation significantly. Moreover, gender is found to be an important factor interacting with the association between procedural justice and cooperative behavior.

INTEGRAL/IBIS search for e-e+ annihilation radiation from the Galactic Center Region

Electron-positron annihilation radiation from the Galactic Center region has been detected since the seventies, but its astrophysical origin is still a topic of a scientific debate. We have analyzed data of the gamma-ray imager IBIS/ISGRI onboard of ESA's INTEGRAL platform in the e$^{-}$e$^{+}$ line. During the first year of the missions Galactic Center Deep Exposure no evidence for point sources at 511 keV has been found in the ISGRI data; the $2 \sigma$ upper limit for resolved single point sources is estimated to be $1.6\times 10^{-4} ph cm^{-2} s^{-1}$.Comment: 6 pages, 3 figures; Cospar 2004. To be published in: Advances in Space Researc

The Role of Canids in Ritual and Domestic Contexts: New Ancient DNA Insights from Complex Hunter-Gatherer Sites in Prehistoric Central California

This study explores the interrelationship between the genus Canis and hunter–gatherers through a case study of prehistoric Native Americans in the San Francisco Bay-Sacramento Delta area. A distinctive aspect of the region\u27s prehistoric record is the interment of canids, variously classified as coyotes, dogs, and wolves. Since these species are difficult to distinguish based solely on morphology, ancient DNA analysis was employed to distinguish species. The DNA study results, the first on canids from archaeological sites in California, are entirely represented by domesticated dogs (including both interments and disarticulated samples from midden deposits). These results, buttressed by stable isotope analyses, provide new insight into the complex interrelationship between humans and canids in both ritual and prosaic contexts, and reveal a more prominent role for dogs than previously envisioned

A comparison of the illness beliefs of people with angina and their peers: a questionnaire study

BACKGROUND: What people believe about their illness may affect how they cope with it. It has been suggested that such beliefs stem from those commonly held within society . This study compared the beliefs held by people with angina, regarding causation and coping in angina, with the beliefs of their friends who do not suffer from angina. METHODS: Postal survey using the York Angina Beliefs Questionnaire (version 1), which elicits stress attributions and misconceived beliefs about causation and coping. This was administered to 164 people with angina and their non-cohabiting friends matched for age and sex. 132 people with angina and 94 friends completed the questionnaire. RESULTS: Peers are more likely than people with angina to believe that angina is caused by a worn out heart (p <0.01), angina is a small heart attack (p = 0.02), and that it causes permanent damage to the heart (p <0.001). Peers were also more likely to believe that people with angina should take life easy (p <0.01) and avoid exercise (p = 0.04) and excitement (p <0.01). CONCLUSIONS: The beliefs of the peer group about causation and coping in angina run counter to professional advice. Over time this may contribute to a reduction in patient concordance with risk factor reduction, and may help to create cardiac invalids

Spectral analysis of the Galactic e+e- annihilation emission

We present a spectral analysis of the e+e- annihilation emission from the Galactic Centre region based on the first year of measurements made with the spectrometer SPI of the INTEGRAL mission. We have found that the annihilation spectrum can be modelled by the sum of a narrow and a broad 511 keV line plus an ortho-Ps continuum. The broad line is detected with a flux of (0.35+/-0.11)e-3 s-1 cm-2. The measured width of 5.4+/-1.2 keV FWHM is in agreement with the expected broadening of 511 keV photons emitted in the annihilation of Ps that are formed by the charge exchange process of slowing down positrons with H atoms. The flux of the narrow line is (0.72+/-0.12)e-3 s-1 cm-2 and its width is 1.3+/-0.4 keV FWHM. The measured ortho-Ps continuum flux yields a fraction of Ps of (96.7+/-2.2)%. To derive in what phase of the interstellar medium positrons annihilate, we have fitted annihilation models calculated for each phase to the data. We have found that 49(+2,-23)% of the annihilation emission comes from the warm neutral phase and 51(+3,-2)% from the warm ionized phase. While we may not exclude that less than 23% of the emission might come from cold gas, we have constrained the fraction of annihilation emission from molecular clouds and hot gas to be less than 8% and 0.5%, respectively. We have compared our knowledge of the interstellar medium in the bulge and the propagation of positrons with our results and found that they are in good agreement if the sources are diffusively distributed and if the initial kinetic energy of positrons is lower than a few MeV. Despite its large filling factor, the lack of annihilation emission from the hot gas is due to its low density, which allows positrons to escape this phase.Comment: 12 pages, 6 figures, accepted in A&

Can illness beliefs, from the common-sense model, prospectively predict adherence to self-management behaviours?: a systematic review and meta-analysis

Objective: To determine whether people’s beliefs about their illness, conceptualised by the common sense model (CSM), can prospectively predict adherence to self-management behaviours (including, attendance, medication, diet and exercise) in adults with acute and chronic physical illnesses. Design and Main Outcome Measures: Electronic databases were searched in September 2014, for papers specifying the use of the ‘CSM’ in relation to ‘self-management’, ‘rehabilitation’ and ‘adherence’ in the context of physical illness. Six hundred abstracts emerged. Data from 52 relevant studies were extracted. Twenty-one studies were meta-analysed, using correlation coefficients in random effects models. The remainder were descriptively synthesised. Results: The effect sizes for individual illness belief domains and adherence to self-management behaviours ranged from .04 to .13, indicating very weak, predictive relationships. Further analysis revealed that predictive relationships did not differ by the: type of self-management behaviour; acute or chronic illness; or duration of follow-up. Conclusion: Individual illness belief domains, outlined by the CSM, did not predict adherence to self-management behaviours in adults with physical illnesses. Prospective relationships, controlling for past behaviour, also did not emerge. Other factors, including patients’ treatment beliefs and inter-relationships between individual illness beliefs domains, may have influenced potential associations with adherence to self-management behaviours