Quenching of Cross Sections in Nucleon Transfer Reactions

Cross sections for proton knockout observed in (e,e'p) reactions are apparently quenched by a factor of ~0.5, an effect attributed to short-range correlations between nucleons. Here we demonstrate that such quenching is not restricted to proton knockout, but a more general phenomenon associated with any nucleon transfer. Measurements of absolute cross sections on a number of targets between 16O and 208Pb were analyzed in a consistent way, with the cross sections reduced to spectroscopic factors through the distorted-wave Born approximation with global optical potentials. Across the 124 cases analyzed here, induced by various proton- and neutron-transfer reactions and with angular momentum transfer l=0-7, the results are consistent with a quenching factor of 0.55. This is an apparently uniform quenching of single-particle motion in the nuclear medium. The effect is seen not only in (d,p) reactions but also in reactions with A=3 and 4 projectiles, when realistic wave functions are used for the projectiles.Comment: 5 pages, 3 figures, accepted to Physical Review Letter

Project for the analysis of technology transfer Quarterly report, 1 Apr. 1970 - 30 Jun. 1970

Operations summary for NASA technology transfer progra

Magnetization of La(2-x)Sr(x)NiO(4+ delta) (0 < x < 0.5) and observation of novel memory effects

We have studied the magnetization of a series of spin-charge ordered La(2-x)Sr(x)NiO(4+delta) single crystals with 0 < x < 0.5. For fields applied parallel to the ab plane there is a large irreversibility below a temperature T(F1) ~ 50 K and a smaller irreversibility that persists up to near the charge ordering temperature. We observed a novel memory effect in the thermo-remnant magnetization across the entire doping range. We found that these materials retain a memory of the temperature at which an external field was removed, and that there is a pronounced increase in the thermo-remnant magnetization when the system is warmed through a spin reorientation transition.Comment: 11 pages, 12 figure

Mind-reading versus neuromarketing: how does a product make an impact on the consumer?

Purpose – This research study aims to illustrate the mapping of each consumer’s mental processes in a market-relevant context. This paper shows how such maps deliver operational insights that cannot be gained by physical methods such as brain imaging. Design/methodology/approach – A marketed conceptual attribute and a sensed material characteristic of a popular product were varied across presentations in a common use. The relative acceptability of each proposition was rated together with analytical descriptors. The mental interaction that determined each consumer’s preferences was calculated from the individual’s performance at discriminating each viewed sample from a personal norm. These personal cognitive characteristics were aggregated into maps of demand in the market for subpanels who bought these for the senses or for the attribute. Findings – Each of 18 hypothesized mental processes dominated acceptance in at least a few individuals among both sensory and conceptual purchasers. Consumers using their own descriptive vocabulary processed the factors in appeal of the product more centrally. The sensory and conceptual factors tested were most often processed separately, but a minority of consumers treated them as identical. The personal ideal points used in the integration of information showed that consumers wished for extremes of the marketed concept that are technologically challenging or even impossible. None of this evidence could be obtained from brain imaging, casting in question its usefulness in marketing. Research limitations/implications – Panel mapping of multiple discriminations from a personal norm fills three major gaps in consumer marketing research. First, preference scores are related to major influences on choices and their cognitive interactions in the mind. Second, the calculations are completed on the individual’s data and the cognitive parameters of each consumer’s behavior are aggregated – never the raw scores. Third, discrimination scaling puts marketed symbolic attributes and sensed material characteristics on the same footing, hence measuring their causal interactions for the first time. Practical implications – Neuromarketing is an unworkable proposition because brain imaging does not distinguish qualitative differences in behavior. Preference tests are operationally effective when designed and analyzed to relate behavioral scores to major influences from market concepts and sensory qualities in interaction. The particular interactions measured in the reported study relate to the major market for healthy eating. Originality/value – This is the first study to measure mental interactions among determinants of preference, as well as including both a marketed concept and a sensed characteristic. Such an approach could be of great value to consumer marketing, both defensively and creatively

fMRI correlates of subjective reversals in ambiguous structure-from-motion

We used fMRI to examine the neural correlates of subjective reversals for bistable structure-from-motion. We compared transparent random-dot kinematograms depicting either a cylinder rotating in depth or two flat surfaces translating in opposite directions at apparently different depths. For both such stimuli, the motion of dots on the different apparent depth planes typically appears to reverse direction periodically on prolonged viewing. Yet for cylindrical but not flat stimuli, such subjective reversals also coincide with apparent reversal of 3D rotation direction. We hypothesized that the lateral occipital complex (region LOC), sensitive to 3D form, might show greater event-related activity for subjective reversals of cylindrical than flat stimuli; conversely, motion-sensitive hMT+/V5 should respond in common to subjective reversals for either type of stimuli, as both are perceived as changes in planar motion. We obtained an event-related measure of neural activity associated with subjective reversals after first factoring out block-related differences between cylindrical versus flat stimuli (and thereby the associated low-level blocked stimulus differences). In support of our hypothesis, only the cylindrical stimuli produced reversal-related activity in contralateral human LOC. In contrast, the hMT+/V5 complex was activated alike by subjective reversals for both cylindrical and flat stimuli. Intriguingly, V1 also showed (contralateral) specificity for rotational reversals, suggesting a possible feedback influence from LOC. These results reveal specific neural correlates for subjective switches of 3D rotation versus translation, as distinct from subjective reversals in general

Offshore rectenna feasbility

A preliminary study of the feasibility and cost of an offshore rectenna to serve the upper metropolitan east coast was performed. A candidate site at which to build a 5 GW rectenna was selected on the basis of proximity to load centers, avoidance of shipping lanes, sea floor terrain, and relocated conditions. Several types of support structures were selected for study based initially on the reference system rectenna concept of a wire mesh ground screen and dipoles each with its own rectifier and filter circuits. Possible secondary uses of an offshore rectenna were examined and are evaluated

The NASA role in major areas of human concern: Health care

Benefits derived from the civilian aeronautics and space effort are discussed in a statement whose focus is on the developments in health care which can be traced to specific NASA program elements. A summary is provided for each case where NASA has been involved in expanding the biomedical technical base, as well as where NASA has been directly instrumental in providing solutions in maintaining adequate health, and correcting health problems when they occur

Power law burst and inter-burst interval distributions in the solar wind: turbulence or dissipative SOC ?

We calculate for the first time the probability density functions (PDFs) P of burst energy e, duration T and inter-burst interval tau for a known turbulent system in nature. Bursts in the earth-sun component of the Poynting flux at 1 AU in the solar wind were measured using the MFI and SWE experiments on the NASA WIND spacecraft. We find P(e) and P(T) to be power laws, consistent with self-organised criticality (SOC). We find also a power law form for P(tau) that distinguishes this turbulent cascade from the exponential P(tau) of ideal SOC, but not from some other SOC-like sandpile models. We discuss the implications for the relation between SOC and turbulence.Comment: 3 pages, 1 figure. Submitted to PRL on 25th February 2000. Revised version re-submitted on 9th May 2000. Second revised version submitted Phys. Rev. E on 26th June, 200

Sensitivity of the creep-rupture properties of nickel-base superalloy sheet to sharp edge-notches in the temperature range of 1000 deg F - 1400 deg F

Edge notch sensitivity in thin sheet nickel alloys under stress at high temperature

Project for the analysis of technology transfer

The special task of preparing technology transfer profiles during the first six months of 1971 produced two major results: refining a new method for identifying and describing technology transfer activities, and generating practical insights into a number of issues associated with transfer programs