An enabling technology for long duration, deep space missions is the availability of a high power, long-lived power supply. The goal of this work is the design of a self-regulating deep space nuclear reactor. The design objectives are to produce 250 kWth for a 25-year period using the presence of...
A hierarchical classification system of Iceland's
watersheds and rivers is presented. The classification
is based on Iceland's substrate, climate, water, biota,
and human cultural influences. The geological formations
of Iceland are very different in character depending on
their age and formation history. Three major types of
formations occur: Tertiary, Plio-Pleistocene,...
Prolactin (PRL) is a peptide hormone that is involved in a number of diverse physiologic roles, particularly with respect to reproduction, including: influencing sexual and parental behaviors, onset of puberty, regulation of seasonal reproduction, follicular maturation, ovulation, luteinization and corpus luteum (CL) function, steroidogenesis, mammary gland development and lactation, testicular...
The purpose of this study is to identify factors that support the likelihood of persistence of academically underprepared community college students to 45 college level credits. Factors considered in this research include: (a) race/ethnicity, (b) age, (c) enrollment status, (d) socio-economic status (SES), (e) first quarter GPA, (f) developmental need,...
As a key factor contributing to slope stability, in-stream habitat for aquatic species (e.g., salmonids), nutrient cycling, and corridors for upland species, riparian vegetation and its maintenance is of critical conservation importance. Subsequently, the chronic degradation of aquatic and riparian ecosystems in the semi-arid and arid landscapes of the western...
A declining population of ring-necked pheasants (Phasianus colchicus) was
studied at Tule Lake National Wildlife Refuge (TLNWR) from the summer of 1990
through the spring of 1993. Pheasant densities/50 ha at TLNWR in 1989, 1991, and
1992 were considerably lower (16.86, 8.49, and 6.81) than the >62 density seen in...
This study involved the determination of the structural layer properties of
aggregate and asphalt surfaced pavements for use in the evaluation of pavement load
carrying capacity and the seasonal effects of moisture. This was achieved by the use
of Nondestructive Testing Methods (NDT) and backcalculation techniques. Pavement
surface deflection measurements...
The loss of all deuterium labels from previous feedings of [2-²H]-,
[3,3-²H₂]-, and [2,3,3-²H₃]arginines had indicated the possible intermediacy
of β-hydroxy- and β-ketoarginine (30 and 31, respectively) in the
biosynthesis of the streptolidine portion of streptothricin F (la).
In order to confirm or refute this evidence, D,L-[2,3,3,5,5-²H₅]-
arginine (32) was...