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The influence of variations in the boundary air layer thickness on transpirtion due to changes in leaf dimension or wind speed was evaluated at a given stomatal resistance (rs) for various combinations of air temperature (Ta) and total absorbed solar energy expressed as a fraction of full sunlight (Sffs). Predicted transpiration was found to either increase or decrease for increases in leaf size depending on specific combinations of Ta, Sffs, and rs. Major reductions in simulated transpiration with increasing leaf size occurred for shaded, highly reflective, or specially oriented leaves (Sffs=0.1) at relatively high Ta when rs was below a critical value of near 500 s m-1. Increases in Sffs and decreases in Ta lowered this critical resistance to below 50 s m-1 for Sffs=0.7 and Ta=20°C. In contrast, when rs was above this critical value, an increase in leaf dimension (or less wind) resulted in increases in transpiration, especially at high Ta and Sffs. For several combinations of Ta, Sffs, and rs, transpiration was minimal for a specific leaf size. These theoretical results were compared to field measurements on common desert, alpine, and subalpine plants to evaluate the possible interactions of leaf and environmental parameters that may serve to reduce transpiration in xeric habitats.

The temperature and water relations of the largleafed, high-elevation species Frasera speciosa, Balsamorhiza sagittata, and Rumex densiflorus were evaluated in the Medicine Bow Mountains of southeast Wyoming (USA) to determine the influence of leaf size, orientation, and arrangement on transpiration. These species characteristically have low minimum stomatal resistances (<60 s m-1) and high maximum transpiration rates (>260 mg m-2s-1 for F. speciosa). Field measurements of leaf and microclimatic parameters were incorporated into a computer simulation using standard energy balance equations which predicted leaf temperature (Tleaf) and transpiration for various leaf sizes. Whole-plant transpiration during a day was simulated using field measurements for plants with natural leaf sizes and compared to transpiration rates simulated for plants having identical, but hypothetically smaller (0.5 cm) leaves during a clear day and a typically cloudy day. Although clear-day transpiration for F. speciosa plants with natural size leaves was only 2.0% less per unit leaf area than that predicted for plants with much smaller leaves, daily transpiration of B. sagittata and R. densiflorus plants with natural leaf sizes was 16.1% and 21.1% less, respectively. The predicted influence of a larger leaf size on transpiration for the cloudy day was similar to clear-day results except that F. speciosa had much greater decreases in transpiration (12.7%). The different influences of leaf size on transpiration between the three species was primarily due to major differences in leaf absorptance to solar radiation, orientation, and arrangement which caused large differences in Tleaf. Also, simulated increases in leaf size above natural sizes measured in the field resulted in only small additional decreases in predicted transpiration, indicating a leaf size that was nearly optimal for reducing transpiration. These results are discussed in terms of the possible evolution of a larger leaf size in combination with specific leaf absorptances, orientations and arrangements which could act to reduce transpiration for species growing in short-season habitats where the requirement for rapid carbon fixation might necessitate low stomatal resistances.

The influence of elevational changes on plant transpiration was evaluated using leaf energy balance equations and well-known elevational changes in the physical parameters that influence water vapor diffusion. Simulated transpirational fluxes for large leaves with low and high stomatal resistances to water vapor diffusion were compared to small leaves with identical stomatal resistances at elevations ranging from sea level to 4 km. The specific influence of various air temperature lapse rates was also tested. Validation of the simulated results was accomplished by comparing actual field measurements taken at a low elevation (300 m) desert site with similar measurements for a high elevation (2,560 m) mountain research site. Close agreement was observed between predicted and measured values of transpiration for the environmental and leaf parameters tested.

Several studies are reported which examine the critical stimuli and responses as well as personality factors important in genital exhibitionism. Using penile volume measurement, sex history questionnaires, personality tests, and behavioral observations, it was found that (1) exhibitionists responded most to mature females and were comparable to normals in reactions to children and men; (2) while exhibitionists indicated narcissistic desires in exposing, in a laboratory study they did not differ from controls in reactions to exposing with various reactions of the female, from sexual arousal and admiration to fear and anger; (3) the only strong features distinguishing exhibitionists from controls and other sexually anomalous subjects were peeping associated with orgasm and outdoor solitary masturbation; (4) exhibitionists seemed to be less assertive and less feminine than controls, but results were weak and inconsistent; (5) exhibitionists and controls did not differ in separation and divorce or marital satisfaction; (6) blood testosterone and penile reactivity of exhibitionists were within normal limits. Overall, the results suggest that most major theories of genital exhibitionism are wanting. It is suggested that narcissism and pedophilia be examined further in connection with exhibitionism.

The interaction of bis-(N-maleimidomethyl) ether with oxyhemoglobin results in covalent linkages of both maleimide groups, converting them to succinyl derivatives of beta93 Cys and beta97 His at their sulfhydryl and imidazolyl side chains, respectively. The resultant hemoglobin is stable, and reveals a left-shifted oxyhemoglobin equilibrium curve in which cooperativity is abolished. This reagent readily traverses the red cell membrane and prevents the sickling reaction upon deoxygenation. It appears to affect none of the activities of the red cell enzymes adversely, nor does it appear to affect the red cell membrane. Since there are several defined effects on the stereochemical status of the molecule conferred by interaction with bis-(N-maleimidomethyl) ether, the precise mechanism of the anitsickling effect remains to be elucidated. A more subtle perturberant will be required to specify a precise antisickling effect. By use of bis-(N-maleimidomethyl) ether a precise locus on the beta chain of human hemoglobin S can be perturbed to produce the desired effect.