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Among all transition metals, Palladium (Pd) has the highest density of states at the Fermi energy yet does not fulfill the Stoner criterion for ferromagnetism. However, its close vicinity to magnetism renders it a nearly ferromagnetic metal, which hosts paramagnons, strongly damped spin fluctuations. In this letter we compare the total and the differential conductance of mono-atomic Pd and Cobalt (Co) contacts between Pd electrodes. Transport measurements reveal a conductance for Co of 1 $G_0$ , while for Pd we obtain 2 $G_0$. The differential conductance of mono-atomic Pd contacts shows a drop with increasing bias, which gives rise to a peculiar {$\Lambda$}-shaped spectrum. Supported by theoretical calculations we correlate this finding with the life time of hot quasi-particles in Pd which is strongly influenced by paramagnon scattering. In contrast to this, Co adatoms locally induce magnetic order and transport through single cobalt atoms remains unaffected by paramagnon scattering, consistent with theory., Comment: 5 pages, 4 figures

The $\Omega$-phase of the liquid sodium $\alpha$-$\Omega$ dynamo experiment at NMIMT in cooperation with LANL has successfully demonstrated the production of a high toroidal field, $B_{\phi} \simeq 8\times B_r$ from the radial component of an applied poloidal magnetic field, $B_r$. This enhanced toroidal field is produced by rotational shear in stable Couette flow within liquid sodium at $Rm \simeq 120$. The small turbulence in stable Taylor-Couette flow is caused by Ekman flow where $ (\delta v/v)^2 \sim 10^{-3} $. This high $\Omega$-gain in low turbulence flow contrasts with a smaller $\Omega$-gain in higher turbulence, Helmholtz-unstable shear flows. This result supports the ansatz that large scale astrophysical magnetic fields are created within semi-coherent large scale motions in which turbulence plays only a smaller diffusive role that enables magnetic flux linkage., Comment: 5 pages, 5 figures, submitted PRL revised version: add one author, minor typo's

Piezoelectric quartz tuning forks have been employed as the force sensor in a dynamic mode scanning force microscope operating at temperatures down to 1.7 K at He-gas pressures of typically 5 mbar. An electrochemically etched tungsten tip glued to one of the tuning fork prongs acts as the local force sensor. Its oscillation amplitude can be tuned between a few angstroms and tens of nanometers. Quality factors of up to 120000 allow a very accurate measurement of small frequency shifts. Three calibration procedures are compared which allow the determination of the proportionality constant between frequency shift and local force gradient based on the harmonic oscillator model and on electrostatic forces. The calibrated sensor is then used for a study of the interaction between the tip and a HOPG substrate. Force gradient and dissipated power can be recorded simultane-ously. It is found that during approaching the tip to the sample considerable power starts to be dissipated although the force gradient is still negative, i.e. the tip is still in the attractive regime. This observation concurs with experiments with true atomic resolution which seem to require the same tip-sample separation.

Piezoelectric quartz tuning forks are investigated in view of their use as force sensors in dynamic mode scanning probe microscopy at temperatures down to 1.5 K and in magnetic fields up to 8 T. The mechanical properties of the forks are extracted from the frequency dependent admittance and simultaneous interferometric measurements. The performance of the forks in a cryogenic environment is investigated. Force-distance studies performed with these sensors at low temperatures are presented.

Two groups of 15 Administrative Specialists, 7lL Military Occupational Speciality (MOS), participated in four job-task refresher training sessions designed to enhance the typewriting of military correspondence. One group performed under a study training method which allowed use of a Correspondence Manual while arranging materials into the correct format, the second under a recall training method which required reliance on memory. Under both methods, participants received knowledge of results concerning both typewriting speed and accuracy. Straight-copy typewriting performance also was measured at each training session. Both training methods produced approximately a 36% increase in format arrangement speed without an associated increase in error. These benefits occurred regardless of a soldier's time in MOS or on-the-job typewriting experience. Straight-copy typewriting performance remained at an average level of twenty-three words per minute across sessions and did not reflect job-tasks typewriting proficiency. Timely and consistent use of knowledge of results was suggested to be the reason for the typewriting improvements obtained under both training methods. Similar use of knowledge of results in an on-the-job environment also should improve job-task typewriting performance, and thereby reduce the need for a formal refresher training program. (Author/YLB)

Results obtained from five techniques for measuring gas-phase ammonia at low concentration in the atmosphere are compared. These methods are: (1) a photofragmentation/laser-induced fluorescence (PF/LIF) instrument; (2) a molybdenum oxide annular denuder sampling/chemiluminescence detection technique; (3) a tungsten oxide denuder sampling/chemiluminescence detection system; (4) a citric-acid-coated denuder sampling/ion chromatographic analysis (CAD/IC) method; and (5) an oxalic-acid-coated filter pack sampling/colorimetric analysis method. It was found that two of the techniques, the PF/LIF and the CAD/IC methods, measured approximately 90 percent of the calculated ammonia added in the spiking tests and agreed very well with each other in the ambient measurements.

The relationship of traditional and nontraditional variables to grades achieved by University of Portland (Oregon) students in five different majors (business, liberal arts, education, nursing, and engineering) was studied. Traditional variables were: the college major; freshman writing class grade; California Aptitude Test (CAT) scores in reading, language arts, and reference; gender; and race. Nontraditional variables were: high school attended, employment, community/church activities, athletics, citizenship, preferred language, parent education, and high school activities. Eighty-nine freshmen completed the CAT, Form D, and the Student Descriptive Surveys. The criterion was the fall 1986 grade point average (GPA). Multiple regression analysis indicated that traditional variables are better than nontraditional variables as predictors of academic achievement among the study group, at least for GPA, a short term measure. Nontraditional variables may prove more effective for academic achievement in long-term prediction of academic achievement and/or persistence. The best predictor of GPA was the grade received in the freshman writing class. Basic skills did not differ significantly among students in five different majors. (Author/SW)

This study examined the criterion validity of curriculum-based measurement (CBM) reading measures in three ways: the relationship between CBM performance and teacher perceptions of student academic functioning; relationship between CBM scores and reading performance on a group achievement test; and the ability of CBM to differentiate between regular education, Chapter 1, and mildly handicapped students. Iowa students (N=1,223) in grades one through eight were used as a testing sample. Results found several non-traditional assessment tools to be effective predictors of current reading group instruction. Reading scores on the Iowa Test of Basic Skills, CBM reading probes, and a teacher rating scale were able to stratify the sample into Chapter 1, resource room, or regular education reading groups with 76% accuracy. These techniques are seen as less time-consuming for special education support personnel and readily applicable for use in program planning and implementation. Includes 24 references. (PB)

Various universities were polled to ascertain expectations, levels and courses of support, management strategies, and perceived trends in requirements for physical education programs in higher education institutions. Scarce resources and declines in student enrollment present difficulties for educators. Suggestions for adapting programs are offered. (DF)