384 research outputs found
Contracts - The Parol Evidence Rule - Exceptions; The Partial Integration and Collateral Contracts Doctrines Durham v. National Pool Equipment Co. of Va., 205 Va. 441 (1964)
An Attitudinal Survey of Forty-Four Juvenile Court Counselors Regarding Due Process Standards in Juvenile Cases
In late 19th century America, new schools of criminological thinking asserted that crime had its origins in a complex blend of environmental and social factors rather than in the moral deficiencies of the offender. Partly as a result of this new attitude the handling of offenses by juveniles became differentiated from adult cases, first through the construction of separate penal institutions and, beginning in 1899, through the establishment of courts specializing in juvenile cases.
This study was undertaken to examine the attitudes of juvenile probation officers toward the Supreme Court’s Kent, Gault and Winship decisions which made a number of due process procedures mandatory in juvenile cases. Hypotheses were examined which asserted that (1) juvenile probation officers have a generally negative attitude toward due process, (2) probation officers with backgrounds in social work have more negative attitudes toward due process than do their colleagues with other types of backgrounds, and (3) within juvenile probation departments supervisors have more positive attitudes toward due process than do their subordinates
Effect of Powdery Mildew, Erysiphe Graminis F. Sp. Tritici on Plant Growth and Grain Yield of Winter Wheat
Plant Patholog
Ecological and Evolutionary Significance of Locomotor Performance in Collared Lizards (Crotaphytus Collaris)
The purpose of this study was to test hypotheses concerning the evolution of locomotor performance in collared lizards. I investigated the roles of natural and sexual selection on locomotor performance in collared lizards by measuring maximal sprint speed in the laboratory, in addition to field-realized sprint speed for the same individuals in three different contexts: foraging, escaping a predator, and responding to a rival intruder. In addition I examined how well performance, morphology, and steroid hormone levels predicted survival and mating success in different age and sex classes. Sprint speed predicted survival only in hatchlings, not adults. Of the three contexts, females used closer to maximal speed while escaping predators than in the other contexts. Adult males, on the other hand, used closer to maximal speed while responding to an unknown intruder tethered within their territory. Sprint speeds during foraging attempts were far below maximal capacity for all lizards. Collared lizards appeared to choose microhabitats near refugia such that maximal speed was not necessary to escape predators. Although natural selection for predator avoidance cannot be ruled out as a strong selective force acting on locomotor performance in collared lizards, especially in females and hatchlings, intra-sexual selection for territory maintenance may be a stronger selective agent on males. To further support the latter hypothesis, I found that only maximal sprint speed predicted mating success. These results represent the first connection of morphology, performance, behavior, and fitness for a population of animals, and suggest that sexual selection may act on whole-animal performance traits.Department of Zoolog
Temporal Integration of Seismic Traveltime Tomography
Time-lapse geophysical measurements and seismic imaging methods in particular are powerful techniques
for monitoring changes in reservoir properties. Traditional time-lapse processing methods treat
each dataset as an independent unit and estimate changes in reservoir state through differencing these
separate inversions. We present a general least-squares approach to jointly inverting time-varying property
models through use of spatio-temporal coupling operators. Originally developed within the medical
imaging community, this extension of traditional Tikhonov regularization allows us to constrain the way
in which models vary in time, thereby reducing artifacts observed in traditional time-lapse imaging formulations.
The same methodology can also accommodate changes in experiment geometry as a function
of time thus allowing inversion of incremental or incomplete surveys. In this case, temporal resolution is
traded for improved spatial coverage at individual timesteps. We use seismic traveltime tomography as a
model problem although almost any geophysical inversion task can be posed within this formalism. We
apply the developed time-lapse inversion algorithm to a synthetic crosswell dataset designed to replicate
a CO2 sequestration monitoring experiment
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Regeneration patterns on some modified staggered-setting clearcuts on the H.J. Andrews experimental forest
A survey of natural regeneration of Doug1as-fir and associated species was made on 15 staggered-setting cuttings four and five years after logging. These areas were on the H. J. Andrews Experimental Forest which is located in the McKenzie River area of western Oregon. Five types of cuttings were represented: (1) four north-south oriented strip clear cuts varying from 50 to 330 feet in width; (2) three east-west orientated strip clear-cut varying from 100 to 300 feet in width; (3) six patch or group clear-cuts varying from one fourth to four acres in size; (4) a shade-seed-tree cutting on which residual trees were left to provide shade and seed; and (5) a typical staggered-setting clear-cut. The modified cuttings were designed to utilize shade from the residual stand to favor regeneration by reducing high surface, soil temperatures, a major deterrent to the establishment of tree seedlings in this area. Results of the survey showed that all of the modified cutting units were better stocked than the typical staggered-setting clearcut and with two exceptions had at least 500 we11-spaced trees per acre. The east-west orientated strips regenerated best with 69 to 89 percent of milacre plots stocked. The small group clearcuts also regenerated well; stocking varied from 8 to 72 percent of milacre plots stocked. The north-south orientated strips were the most poorly stocked group of small cuttings with from 35 to 61 percent of milacre plots stocked. The shade-seed-tree cutting had 61 percent of plots stocked and the staggered-setting clearcut 28 percent of plots stocked. The statistical analysis indicated that the parameter of shade hours per plot was consistently related to regeneration of all species together and of Douglas-fir alone. The degree of this relationship varied considerably between types of units and to a lesser extent among units of a particular type. In addition there was some evidence that intermittent shading was more effective in favoring regeneration than a similar amount of shade received in a single period of time. Distance from seed source was not found to be related to stocking on the small cutting units studied. This author concludes that consideration should be given to the use of special cutting methods such as east-west orientated strip clearcuts, small patch clearcuts, and shade-seed-tree cuttings, to aid in natural regeneration of Douglas fir, especially on severe sites. These cuttings should be laid out primarily to provide shade rather than from the standpoint of seed dispersal
Characterising the interactions between unicast and broadcast in IEEE 802.11 ad hoc networks
This paper investigates the relative performance of unicast and broadcast traffic traversing a one-hop ad hoc network utilising the 802.11 DCF. An extended Markov model has been developed and validated through computer simulation, which successfully predicts the respective performance of unicast and broadcast in a variety of mixed traffic scenarios. Under heavy network traffic conditions, a significant divergence is seen to develop between the performance of the two traffic classes - in particular, when network becomes saturated, unicast traffic is effectively given higher precedence over broadcast. As a result, the network becomes dominated by unicast frames, leading to poor rates of broadcast frame delivery
Managing fire-prone forests in the western United States
The management of fire-prone forests is one of the most controversial natural resource issues in the US today, particularly in the west of the country. Although vegetation and wildlife in these forests are adapted to fire, the historical range of fire frequency and severity was huge. When fire regimes are altered by human activity, major effects on biodiversity and ecosystem function are unavoidable. We review the ecological science relevant to developing and implementing fire and fuel management policies for forests before, during, and after wildfires. Fire exclusion led to major deviations from historical variability in many dry, low-elevation forests, but not in other forests, such as those characterized by high severity fires recurring at intervals longer than the period of active fire exclusion. Restoration and management of fire-prone forests should be precautionary, allow or mimic natural fire regimes as much as possible, and generally avoid intensive practices such as post-fire logging and planting
Normothermia is protective during infrarenal aortic surgery
AbstractPurpose: Mild hypothermia has been suggested to be protective against tissue ischemia during aortic operations. However, recent studies have documented detrimental cardiac effects of hypothermia during a variety of operative procedures. The influence of different warming methods and the impact of hypothermia during standard aortic procedures was assessed. Methods: One hundred patients who underwent repair of infrarenal aortic aneurysms or aortoiliac occlusive disease were prospectively randomized into 2 groups, receiving either a circulating water mattress or a forced air warming blanket. Adjuvant warming methods were standardized. The day before surgery, 48-hour Holter monitors were applied and interpreted by a cardiologist blinded to the treatment. Randomization resulted in equivalent groups with regard to patient history, indications for surgery, body mass index, length of surgery, and fluid requirements. Results: Core temperatures were significantly warmer during surgery (36.3°C ± 0.7°C vs 35.4 ± 0.8°C) and after surgery (36.4°C ± 0.7°C vs 35.6°C ± 0.9°C) in patients with forced air warming (P < .001). The circulating water mattress group had significantly more metabolic acidosis perioperatively (P = .03). Postoperative length of stay, cardiac complications, and death rates were not significantly different. Subgroup analysis of 83 aneurysm patients comparing normothermia with hypothermia (temperature less than 36°C) on arrival to the recovery room identified decreased cardiac output (P = .02), thrombocytopenia (P = .02), elevated prothrombin time (P = .04), and inferior Acute Physiology and Chronic Health Evaluation (APACHE) II scores (P < .001) in the hypothermic group. Holter analysis revealed more sinus tachycardia (ST) segment changes and ventricular tachycardia in hypothermic aneurysm patients (P = .05). Conclusion: Patients treated with forced air blankets had significantly less metabolic acidosis and were kept significantly warmer than those treated with circulating water mattresses. Patients with aneurysms that were kept normothermic had a significantly improved clinical profile, with fewer cardiac events on the Holter recordings. We therefore conclude that (1) normothermia is protective for infrarenal aortic surgical patients; and (2) forced air warming blankets provide improved temperature maintenance compared with circulating water mattresses. (J Vasc Surg 1998;28:984-94.
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