Photoemission Electron Microscopy as a tool for the investigation of optical near fields

Photoemission electron microscopy was used to image the electrons photoemitted from specially tailored Ag nanoparticles deposited on a Si substrate (with its native oxide SiO$_{x}$). Photoemission was induced by illumination with a Hg UV-lamp (photon energy cutoff $\hbar\omega_{UV}=5.0$ eV, wavelength $\lambda_{UV}=250$ nm) and with a Ti:Sapphire femtosecond laser ($\hbar\omega_{l}=3.1$ eV, $\lambda_{l}=400$ nm, pulse width below 200 fs), respectively. While homogeneous photoelectron emission from the metal is observed upon illumination at energies above the silver plasmon frequency, at lower photon energies the emission is localized at tips of the structure. This is interpreted as a signature of the local electrical field therefore providing a tool to map the optical near field with the resolution of emission electron microscopy.Comment: 10 pages, 4 figures; submitted to Physical Review Letter

Age, Sex, and Socioeconomic Status: Related Factors in Motivations for Exercise

The purposes of this study were (a) to determine if age, sex, and socioeconomic status were related factors in motivations for exercise in adults who participated in planned regular physical activity/exercise (b) to ascertain the differences in motivations/reasons given for participating in planned regular physical activity/exercise, during leisure time, between the regular exerciser and the non-regular exerciser, and (c) to gather demographic data pertinent to adult males and adult females who engage in planned regular physical activity/exercise, during their leisure time, and those who do not. A sample of 692 adults who identified themselves as regular exercisers (87.4%) or nonregular exercisers (12.6%) completed the Exercise Motivation Inventory-2 developed by Markland and Ingledew (1997). Resulting data were analyzed utilizing descriptive statistics, t-tests with a Boneferoni adjustment, Levene’s Test for Equality of Variances, One-way ANOVA, MANOVA, and Tukey Post Hoc Analysis. All populations ranked the subscale of “positive health” as the primary motivation to participate in regular exercise. Other subscale rankings varied upon the population responding. The most common other high ranking subscales identified, regardless of age, sex, or socioeconomic status were strength and endurance, weight management, ill-health avoidance, enjoyment, nimbleness, and appearance. Resulting data indicated significant findings between males and females for five subscales (enjoyment, challenge, social recognition, competition, and weight management), between males and females in three of the four age groups for four subscales (social recognition, competition, weight management, and strength and endurance), and between different levels of socioeconomic status for 10 of the subscales (enjoyment, challenge, social recognition, affiliation, competition, ill health avoidance, positive health, appearance, strength and endurance, and nimbleness). Significant findings were found between the regular exerciser and the non-regular exerciser in 12 of the 14 subscales

Sanierputz. Aenderung der Hydrophobie durch Salzloesungen Schlussbericht

SIGLEAvailable from TIB Hannover: F95B1790 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDeutsche Forschungsgemeinschaft (DFG), Bonn (Germany)DEGerman

Quality assurance in age estimation based on aspartic acid racemisation

Estimates of the age of living and dead individuals, obtained in order to answer legal or social questions, require minimum quality standards in order to guarantee data quality. We present an outline strategy (with recommendations) for the attainment of quality assurance in age estimation based on aspartic acid racemisation. The strategy is based on a definition of minimum standards for laboratories, including documentation of procedures, methodology and levels of expertise, and the formulation of guidelines for intralaboratory and interlaboratory quality control