No description available.

A limnological study of the Dundas Marsh region, involving the main physical, chemical and biological factors, and their interrelationships, as investigated during the summer seasons of 1946 to 1948, inclusive. The account includes a review of pertinent historical and descriptive material on the entire region. / Thesis / Master of Arts (MA)

When crested wheatgrass (Agropyron desertorum) grows in mixture with sagebrush (Artemisia tridentata), its production declines. Its production increases when grown in mixture with fourwing saltbush (Atriplex canescens), according to previous reports. This study investigated soil water extraction and potassium (K) nutrition of the two shrubs to identify possible causes of the differential responses of crested wheatgrass. Crested wheatgrass had reduced, rather than increased, nitrogen (N) and K yield in mixture with fourwing saltbush. No differences in N and phosphorous (P) concentrations were observed between sagebrush and fourwing saltbush, but fourwing saltbush had a much higher K concentration and returned nearly twice as much K to the soil as sagebrush by throughfall and litterfall. Throughfall additions were much greater than those from litterfall. AK-fertilization/water-stress, two-factor greenhouse experiment was conducted with crested wheatgrass. High- and medium-K-fertilization treatments had highest tissue K concentration, but biomass yield was reduced in waterstressed plants with high K-fertilization. A difference of 1.56 MPa in osmotic adjustment was observed between waterstressed plants with high K-fertilization and irrigated, low-K-fertilization plants. These results suggest that K accumulation in fourwing saltbush may be a factor for enhanced crested wheatgrass productivity. Crested wheatgrass grown in mixture with fourwing saltbush had lowered predawn and mid-day xylem water potentials compared with monoculture and sagebrush mixture plots, but no other treatment differences were observed for any species. Fourwing saltbush monoculture plots had the most uniform water extraction rates and may compete less for water than sagebrush when crested wheatgrass extraction rates are highest.

The relationships of estradiol-17-beta, progesterone, and LH in the early postpartum St. Croix ewe were monitored during the breeding season in 1988. A second group of non-postpartum, ovariectomized St. Croix ewes were used to determine non-ovarian levels of progesterone for comparison. Results of this study indicate that: 1. The short duration rise in progesterone exhibited by some ewes is indicative of an ovulation. 2. Ewes that do exhibit a short luteal phase prior to the first "normal" luteal phase have a longer period from parturition to the first "normal" luteal phase. 3. Serum levels of LH increase beginning 3 days postpartum. 4. There is a strong relationship between the concentration of estradiol and the exhibition of behavioral estrus in the postpartum ewe. 5. There appears to be a definite but somewhat irregular pulsatile release pattern of estradiol from the follicle of the postpartum ewe. The ability of the endocrine system of the St. Croix to return to functional levels of production and release during the first 15 days postpartum is likely related to their relatively short postpartum intervals and subsequent pregnancies.

Yes / This research critically analyzes the Interpretive Ranking Process (IRP) using an illustrative empirically derived IS project failure related case study to articulate a deeper understanding of the method. The findings emphasize the suitability of the method for a number of practical applications, but also highlight the limitations for larger matrix sized problems. The IRP process to derive the dominance between IS project failure factors is judged to be methodical and systematic, enabling the development of clear dominating interactions.

<p>Businesses carrying out related diversification moves with the objective to gain synergy effects have been a frequently occurring phenomenon since the midst of the past century. Plenty of models have been constructed, mainly using external data, in order to predict the outcome of these moves, but a high degree of contradictory results in empiric testing shows that current models are insufficient. Our objective is to present a model which also takes into account the internal data presented by the line of research called horizontal strategies, with the aim of moving towards a more accurate explanatory model for related diversification. This is a study of literature which resulted in a model which may be used for approximations as a strategic planning device. Our main conclusions are that further empirical testing, mainly regarding the behaviour of costs for implementing interrelationships, is necessary in order to create an accurate, explanatory model for predicting the outcome of related diversification.</p>

No description available.

A study to determine habitat differences of benthic macroinvertebrates was conducted on the upper Strawberry River, Utah. The investigation was part of a large scale project to determine minimum stream flow requirements for trout. The effects of time, habitat, depth and velocity on the distribution of benthic fauna were evaluated. Samples of benthic invertebrates (146 total) were collected every 2 months at 8 stations on the river from November, 1975 through August, 1976. Representatives of 59 taxa were collected. Eight taxa comprised 90 percent of the mean annual community standing crop in numbers. Biomass was not dominated by any group of taxa. Community standing crop decreased from late Fall 1975 until early Summer 1976. The largest increase in standing crop occurred during August. Prediction of benthic distribution through the use of depth and velocity categories was unsuccessful. Three-dimensional plots of the relative density of a taxon versus depth and velocity indicated the contagious nature of the animals' distributions but their preference for specific categories could not be demonstrated. The results suggested that macroinvertebrates could tolerate large variations in current and depth and that these physical factors are only indirectly related to faunal distribution. Results of analysis of variance and covariance showed time to be the factor which influenced the distribution of most taxa (85%), followed by the time x habitat interaction (20%), velocity (18%), habitat (11%), and depth (9%). Comparisons in animal abundance were made between 4 riffles and 4 ''pools". These two habitats did not differ significantly in substrate type or velocity, however depth did show significant differences. Results of nonparametric tests suggested that the majority of taxa migrated into "pools" during periods of snow, ice, and low flows, an indication that "pools" may provide refuge to macroinvertebrates during periods of stream dewatering and diversion.

Fasting and ketogenic diet prevent seizures in epileptic children, magnesium-deficient rats and other animal models of seizure disorders. This effect has been attributed to increased levels of circulating ketone bodies. The purpose of this study was to determine the role of serum ketone bodies, measured as beta-hydroxybutyrate (BHB), in preventing audiogenically-induced seizures in weanling rats fed a magnesium-deficient diet for 17 days. The effect on seizure susceptibility was investigated by feeding a magnesium-deficient diet to weanling rats for 17 days. Fasting and ketogenic diet (dietary medium chain triglycerides, MCT) markedly decreased seizure incidence that was associated with increased serum BHB level. Also, rats fasted for 24h or fed 28 percent dietary MCT had decreased seizure incidence as compared with rats fed 3 percent dietary MCT or rats fasted for 6h. These effects were not caused by differences in caloric density or percentage of calories from fat in the diets. Gavaging 2 mmoles of BHB resulted in lower seizure incidence; as compared with rats gavaged with 0.5 mmoles BHB when measured 30 min after dosing. In contrast, gavaging 5.6 mmoles of glucose resulted in increased seizure incidence in 24-h-fasted rats. Gavaging 5.6 mmoles of glucose with 0.5 mmole of BHB simultaneously resulted in higher seizure incidence than gavaging with 2.0 mmole BHB and 1.4 mmole glucose simultaneuosly. In addition, gavaging 5.6 mmoles of glucose with 2 mmoles of BHB resulted in higher seizure incidence than gavaging 2 mmoles of BHB alone, which markedly reduced seizure incidence in fasted animals. Fasting, ketogenic diet (MCT) and gavaging BHB increase serum BHB and decrease serum glucose concentrations . Gavaging glucose reduced serum BHB and increased serum glucose concentration. There was an inverse relationship between serum BHB and glucose in all treatments of this study. Although some treatments affected serum minerals, these effects were not consistent among experiments. Therefore, fasting, ketogenic diet (MCT) and gavaging BHB or glucose does not affect serum minerals markedly or consistently; and modifications in serum minerals caused by these treatments do not account for this effect on seizure incidence and severity. Finally, increases in serum BHB and decreases in serum glucose were consistently associated with dose-dependent reductions in seizure susceptibility of rats fed a magnesium-deficient diet for 17 days.

The statement by the Director of the Australian Institute of Family Studies - that Australia needs a Family Policy in order to make Australians more aware of the crucial role of the family in the development of human competence - provides the benchmark for this study, A content analysis of Australian and overseas family policy documents reveals that present approaches are ad hoc and fragmented - although there is a definite move towards a developmental and integrated approach. In this study it is argued that family policy has a valid role in providing the context of education throughout the life cycle of individuals, simply because, together with education (in its widest sense of human development) it provides the construction of social reality for members of Australian society. Three metaphorical models of reality promoted by different education approaches are delineated: (i) The Clockwork world of the megamachine and the image of education as a means of production, (ii) the Secular Humanistic world of dichotomies and the image of education as a means of intellectual growth, and (iii) The World of Interrelationships and Wholeness and the image of education as a life long journey A review of the literature on the relationship between family and education reveals an historial development from separation, through collaboration to integration of these two important influences in human development. The central issue identified for policy is that of the twin horns of a dilemma. Either the terms of policy are so strictly defined that it becomes a self-limiting selffulfiling prophecy, or there is no basis at all for constructive discussion because of the present mass of unorganised detailed material. A way out of this dilemma is proposed with the design of an integrated perspective on the family for use by policy makers, educators and families themselves. Six interrelated models of the family (Cultural, Functional, Survival, Developmental, Legal and Structural) are defined and their links to the dynamics of an actual family are described. The implications of this new conceptual tool are briefly discussed and it is argued that any approach in policy or practice that ignores the mutlifaceted dimensions of this integrated perspective on the family is incomplete. Attached to this Field Study are: (A) A content analysis of twenty years of family policy with an emphasis on Australian material; (5) A comprehensive bibliography cf Australian and overseas material. Each of these attachments could act as source documents in themselves for further research in this area.