"Through the digits, through the fingers": Variations on the string figure as imaginary digital medium.

This article considers artistic engagements with string figure performance and collection as 'imaginary' articulations of digital media. As an object of anthropological inquiry, the string figure emerges in 1888 with a short paper by Franz Boas. Encouraged by more mainstream publications by Caroline Furness Jansen (2008) and Kathleen Haddon (1930), over the course of the 20th century the string figure would become a model through which largely western writers and artists have explored both the anxieties and dreams of ideal, embodied and networked communication technologies.

Familiarity, proximity and self-injurious behaviors.

This paper introduces familiarity and proximity of direct-care staff as possible contributors to the etiology of self-injurious behaviors. Analysis suggests that research workers consider these two variables when evaluating the etiology of such behaviors with specific reference to positive and negative reinforcement paradigms.

Anorexia nervosa: a misdiagnosis of the adolescent male.

The rarity of anorexia nervosa among the male population is discussed with primary reference to differences from female symptomology. A case is presented which implies that anorexia nervosa in the male may be a marker for other more severe pathology. These findings suggest a diagnostic strategy based on familial, behavioral, environmental, educational, and psychological factors.

School discrimination and the high school dropout: a case for adolescent advocacy.

The literature supports the theory that high school dropouts are unable to find employment when they leave school, and that girls who dropout are more likely than boys to return. It was hypothesized that schools may not want to take back students who had once dropped out of school. To investigate the schools' response to dropouts trying to return, three actors were used to portray a male dropout, a female dropout and a parent of a dropout.

Coupled-column system for quantitating low levels of aflatoxins.

The combination of Styragel and Florisil columns allows recovery of aflatoxins at low levels. Two switching valves between the columns reduce the analysis time and exposure to solvents. Florisil is modified with oxalic acid, allowing recovery of aflatoxins at levels below 500 pg.

Degradation of aromatic compounds in ground-water, and methods of sample preservation.

The degradation of acenaphthylene, acenaphthene, 2-methylnaphthalene, 2-methylindene, 3-methylindene and indene in water solutions was studied. These compounds at the 25-150 mug/l. level were almost totally degraded at ambient temperature within three days.

Analysis of various Iowa waters for selected pesticides: atrazine, DDE, and dieldrin-1974.

Atrazine, DDE, and dieldrin were extracted and concentrated from various surface, subsurface, and finished waters using the macroreticular resin method. Organic components in the concentrates from these waters were separated by gas chromatography; the amounts of the three pesticides in the waters ranged from 0.5 to 42,000 parts per trillion by weight.

Relative sensitivity coefficients for rare earths in spark-source mass spectrometry.

Relative sensitivity coefficients have been computed for rare earth elements according to empirical models which have been proposed in the literature. Explanations concerning differences between the computed and observed values are based upon possible instrumental discrimination effects which negate some processes occurring in the ion source. Computations relating elemental physical constants to observed results in a semi-random manner are shown which support this contention.

Automatic control of the ion-illumination angle in a spark-source mass spectrometer.

Automatic adjustment of only the spark-gap width in a spark-source mass spectrometer does not ensure that optimum conditions of electrode geometry are maintained with respect to the ion-optics system. A device has been developed which simultaneously maintains a constant gap width and also a more constant z-axis ion-illumination angle. This is the first development to utilize ion-optics parameters to adjust the sparking electrodes automatically.

A semi-automatic system for operation of electrical detection for a spark-source mass-spectrometer.

A semi-automatic control system has been developed for a spark-source mass-spectrometer, which permits close interaction between the operator, the instrument via electrical ion-detection and a computer via time-sharing (remote terminal) facilities.

Determination of rare earths in selected rare earth matrices by spark source mass spectrometry.

Three methods of preparing rare earth samples for mass spectrographic analysis are presented. Techniques for adding appropriate internal standards are described and relative sensitivity factors for rare earth impurities in rare earths, lanthanum, yttrium and scandium matrices are presented. Although indium has some value as an internal standard in rare earth samples, best analytical results are obtained when selected rare earths are used as internal standards.

Application of low-cost operational amplifiers to electrical detection in spark-source mass spectrometry.

An electrical detection system for spark-source mass spectrometry has recently been developed. This brief addendum describes an improvement in the signal amplification and its conversion to digital output which has important implications in the future development of electrical detection.

An electrical detection system for a spark-source mass spectrograph.

An electrical detection system has been developed which can be used with the high-frequency spark-source mass spectrograph. Details of the system are discussed and examples are given illustrating its advantages (rapidity and precision). One distinct advantage of electrical detection is that a constant volume of sample material is used for each impurity determination.

Thermochemical Properties of Xenon Difluoride and Xenon Tetrafluoride from Mass Spectra.

The standard heats of formation for gaseous xenon tetrafluoride and xenon difluoride and the average strength of the bonds in these molecules have been determined from appearance-potential data obtained with a mass spectrometer. The experimental values are compatible with theoretical estimates of these quantities.