Dropping the Hot Potato: Rescusitating the Permissive Withdrawal Rules in the Model Rules of Professional Conduct

Critical analysis of the Hot Potato Rule in attorney ethics through pragmatic, textual, and philosophical approaches

The effects of meso-scale topography on the performance of engineered soil covers

Understanding the hydrological controls on subsurface flow and transport is of considerable importance in the study of reclaimed landscapes in the oil sands region of Canada. A significant portion of the reclaimed landscape will be comprised of a thin veneer (~ 1 m) of clay-rich reclamation soil overlying saline-sodic shale overburden, which is a waste by-product from the mining process. The global objective of this study was to investigate the first-order controls on soil moisture and salt transport dynamics within clay-rich reclamation covers overlying low permeability waste substrates. The study site is located in a cold, semi-arid climate in the oil sands region of northern Alberta. Preferential flow was the dominant mechanism responsible for the development of perched water table conditions on the cover-waste interface during the spring snow melt. Hydrological and geochemical data indicated that snowmelt infiltration occurs via the macroporosity while the ground is still frozen. An isotope hydrograph separation conducted on water collected in a weeping tile confirmed the presence of fresh snowmelt water at the onset of subsurface flow. This water transitions to a chemical signature that is comprised of approximately 80% connate pore water as a result of chemical equilibration between pore water in the soil matrix and fresh water in the macropores.Detailed mapping of the spatial distribution of soil moisture and salts within a reclamation cover indicated the lower-slope positions are wetter due to the accumulation surface run-off and frozen ground infiltration in spring. Increased soil moisture conditions in lower-slope positions accelerate salt ingress, while drier conditions in middle and upper-slope positions attenuate salt ingress. The data indicated that fresh snowmelt water is bypassing the soil matrix higher in the cover profile. Subsurface flow and deep percolation are key mechanisms mitigating vertical salt ingress in lower and upper slope positions. The mesotopography of the cover-waste interface imposes a direct control on the depth of perched water and the downslope routing of water. Undulations in the cover-waste interface cause the depth of perched water to vary considerably (± 20 – 60 cm) over short distances (< 5 m), while saturated subsurface flow is routed through the lowest elevations in the cover profile. A numerical analysis of subsurface flow was able to simulate both the discharge rate and cumulative volume of flow to a weeping tile. Composite hydraulic functions were used in the simulations to account for the increased hydraulic conductivity and drainable porosity created by the macroporosity at near-saturated conditions. The transient Na+ concentration of discharge water was modelled using the concept of an equivalent porous medium. The good match between measured and modelled data verified the conceptual model, which contends that saturated subsurface flow is dominated by the fracture network and that the concentration of discharge water is function of the depth of perched water. Finally, the results from this study suggest the mesotopography of the cover-waste interface could be used to manage ‘excess’ water and salts within the landscape

The effects of winter feeding systems on beef cow performance, soil nutrients, crop yield and system economics

A study was conducted on an annual cropped field near Lanigan, Saskatchewan over two years (2005-2006, 2006-2007) to evaluate the effects of three extensive winter feeding systems (bale grazing (BG), swath grazing (SG) and straw-chaff grazing (ST-CH)) and one intensive winter feeding system (drylot (DL)) on cow performance, soil nutrients, crop yield and system cost of production. Differences in BW (

Evaluation of required splice lengths for reinforcing bars in masonry wall construction

Relatively few research efforts have focused on splice length requirements for reinforced masonry, despite the significant impact of these requirements on the safety, economy, and constructability of masonry walls. The Canadian masonry provisions for splice lengths in CSA S304.1-04 are taken directly from the Canadian concrete design standard, CSA A23.3-04, and thus do not necessarily reflect factors unique to masonry construction. Provisions in American masonry standard TMS 402-13/ACI 530-13/ASCE 5-13 are based on test results of double pullout specimens, but may be overly conservative due to shortcomings of the specimen type chosen. The purpose of this study is to examine the splice lengths needed for flexural masonry elements reinforced with bar sizes typically used in Canadian masonry construction. In this study, 27 wall splice specimens and 12 double pullout specimens were constructed. The wall splice specimens were tested horizontally in four point loading, while the double pullout specimens were tested in direct tension. Results from the double pullout specimen testing suggest that the techniques used at the University of Saskatchewan (U of S) are reasonably similar to those of the National Concrete Masonry Association (NCMA), and are thus adequate to assess current provisions in the American and Canadian standards. A predictive equation for the tensile resistance of spliced reinforcement was developed from the results of the wall splice specimen testing. This predictive equation was then adjusted to incorporate an adequate margin of safety for calculating splice length requirements for design purposes, using a five percent quantile approach. The adjusted predictive equation was then extrapolated to determine the splice lengths corresponding to the nominal yield strength of the reinforcement. These splice lengths were compared to current code provisions. It was found that the current CSA S304.1-04 Class B provisions, used almost exclusively in construction, are conservative for No. 15, 20, and 25 bars. In contrast, the TMS 402-13 provisions were overly conservative for all three bar sizes. Changes to the bar size factors of the current provisions for both codes were recommended to bring better consistency to the requirements of the two codes, and thus ensure the safety, economy, and constructability of masonry walls

Effect of winter feeding systems on soil nutrients

Non-Peer Reviewe

Storm-Dominated Diatomite: Transport and Deposition From Micro-Texture

Unusually thick accumulations of diatomite and diatomaceous mud- and siltstones occur throughout the Mio-Pliocene along the Pacific margin. These extensive micro-fossil assemblages represent an important biostratigraphic resource, record of environmental conditions, and are economically relevant as unconventional reservoirs, sources and seals. Most depositional models for diatomaceous sediments tend to emphasize diatom productivity sufficient to overcome siliciclastic dilution and reflect a low-energy depositional regime with passive settling of diatoms through the water column. However, the diatomaceous sediments of the Pisco Basin, Peru, have been observed in longitudinally bedded, wavy, non-parallel laminated deposits, interpreted as hummocky-swaley cross-stratification. Other outcrop observations include tempestite-like sequence stacking, normal grading, and syndepositional soft-sediment deformation, suggesting a bedload orgin for the Pisco diatomite under a combined-flow regime and storm-like conditions. Such diatomite can also be found associated with fossil marine vertebrate burial. This study sought to investigate these findings at the level of micro-texture though thin section imaging, SEMs of freshly parted rock surfaces, and micro-CT modeling. Notable textures observed include graded micro-couplets containing a normally graded xii silt component and reverse graded diatomaceous component, predominantly observed in hummocky-swaley cross-stratified diatomite and swale drapings. In a stacked channel complex of interlaminated diatomite-siltstone, wave-enhanced sediment gravity flows were found as a graded triplet capped in purest diatomite. These suggest a bedload origin for much of the Pisco’s diatomaceous sediments, and mirror textures previously derived in mudstone flume experiments, further suggesting that diatoms may entrain, flocculate, and accumulate in a manner effectively similar to clays. These findings also call into question the diatomite necessarily reflects a low-energy to passive depositional regime. Likewise, with respect to the Pisco Basin, it remains probable that much of its fossil content encased in diatomaceous sediments met their fate under a tractional regime rather than due to the slow-settling of diatoms and their components

Improving Grazing Capacity Through Introduction of Bloat Free Legumes in Existing Pasture Stands

Three experiments were conducted over 5 yr to evaluate the inclusion of bloat-free legumes through sod-seeding in existing pasture stands, with respect to plant persistence under grazing pressure, animal performance, rumen fermentation, enteric methane production and economic impact. Experiment 1 was separated into two parts, the first which assessed 2 legumes (CMV; cicer milkvetch [Astragalus cicer L] and sainfoin [SAIN; Onobrychis viciifolia Scop.]) at 2 stages (vegetative and late flower) incubated with alfalfa (ALF; Medicago sativa) at 5 inclusion rates 0:100; 25:75, 50:50, 75:25 and 100:0 (as DM) incubated in batch culture. The second part of experiment 1 assessed CMV and ALF at the vegetative physiological stage (16-30 cm stem length, no buds, flowers or seed pods) were incubated in ratios of 25:75, 50:50, 75:25 and 100:0 (as DM) in RUSITEC. In batch culture, dry matter disappearance (DMD) increased linearly (P ≤ 0.01), propionate concentration (mol 100mol-1) increased linearly (P = 0.02), and methane (mg g-1 DMD) decreased linearly (P ≤ 0.01) with vegetative CMV inclusion. In RUSITEC, DMD, ADF and NDF digestibility were increased quadratically (P ≤ 0.01) with increased vegetative CMV inclusion. Total ruminal SCFA production (mmol d-1) did not change (P=0.59); however, acetate to propionate ratio and NH3-N (mmol d-1) were linearly decreased (P<0.01), and total microbial protein synthesis and efficiency of microbial protein synthesis were linearly increased (P<0.05) with increased vegetative CMV inclusion. In experiment 2, a two-year (2017, 2018) replicated (n=6) experiment was conducted to evaluate the effect of bloat-free legumes on grazing animal ruminal fermentation, ruminal microbial populations, and enteric methane production. Each yr, 15 ruminally cannulated cows (average 739 kg ± 40kg) were randomly allocated to 1 of 3 replicated (n=6) treatments: grazing sod-seeded SAIN; grazing sod-seeded CMV; or grazing non-sod-seeded control (CONT). Total short chain fatty acid production (mmol d-1; P = 0.59) and acetate (mol 100mol-1; P = 0.26) did not differ between treatments. Propionate increased linearly (P ≤ 0.01) and butyrate decreased linearly (P ≤ 0.01) with increased CMV inclusion. Acetate to propionate ratio decreased linearly (P=0.01) in cattle grazing CMV paddocks compared CONT or SAIN. Ruminal ammonia (NH3-N) concentration and plasma urea nitrogen were linearly increased (P ≤ 0.01) in cattle grazing CMV paddocks compared to SAIN and CONT. Enteric methane (g kg-1 DMI) and ruminal microbial populations were not impacted by treatment. In experiment 3, a five-year experiment evaluated the effects of sod-seeding SAIN and CMV into mixed alfalfa-meadow bromegrass (Lanigan, SK) (CONT) or monoculture alfalfa (Lethbridge, AB) (CONT) stands on pasture productivity, steer performance, and economics. At Lanigan, SAIN decreased (treatment × year, P = 0.01) from 13% in yr 1 to 2% in yr 2 (% plant population) and did not differ thereafter, while CMV, maintained a proportion of 16% in the stand. Forage yield was greater (treatment × year; P < 0.01) in yr 1 in the SAIN and CMV milkvetch treatments compared to CONT. Dry matter intake (DMI) of steers was greater only in yr 5 and ADG was greater (P < 0.01) in SAIN and CMV treatments compared to CONT. At Lethbridge, SAIN decreased (treatment × year; P = 0.01) from 46 to 17% (% DM yield), while CMV maintained its proportion at 11% over 5 yr. Forage yield increased (treatment × year; P < 0.01) only in yr 2 and 3 of SAIN, compared to CMV or CONT. Average daily gain (kg d-1) was not affected by treatment (treatment × year; P = 0.12). At Lanigan, SAIN and CMV generated greater gross returns compared to control; however, once establishment costs were applied there were no differences in present value of net returns. Throughout the three experiments outlined in this thesis, the data suggests possible increases in energetic efficiency and microbial protein synthesis may be observed in cattle grazing mixed CMV pasture compared to ALF when grazed at equal maturity. Results also suggests CMV may be more persistent in mixed pasture under variable environmental conditions, when compared to SAIN; however, risk associated with increased undesirable species in sod-seeded paddocks were observed and cannot be overlooked. Costs associated with sod-seeding CMV and SAIN, such as fertilizer and seed price, combined with variable forage yield and animal performance, reduced the economic feasibility of sod-seeding these species which may limit producer uptake of this type of pasture rejuvenation. The results of these experiments highlight the dynamic environment of mixed species pastures, as results varied depending on level of legume inclusion in pasture, species sod-seeded, and existing pasture species. More research is required to determine the agronomic best management practices for pasture rejuvenation, the impact of pre-existing pasture species on newly introduced species, and the impact of non-tanniferous legumes, such as CMV, on livestock production

The Effects of Levamisole, CORYNEBACTERIUM PARVUM, and Unblocked Lymphocytes on Mice Injected with Herpes Virus Type 2-transformed Cells

The association between herpes simplex virus type-2 and carcinoma of the cervix is becoming increasingly strong (Rawls, et al., 1976 ; Rapp and Duff, 1974; Hollingshead, et al-, 1973). This study demonstrates the ability of certain known immunostimulators to beneficially· alter the immune status of mice injected with HSV-2 transformed cells. Balb/c mice were randomly divided into 6 groups. Group 1 mice were used as negative controls and received no tumor cell injection. All other groups received subcutaneous injections of 1 x 106 cells/ mouse. Tumor therapy by means of irrmunostimulation was started for each group of mice 1 day after the initial tumor cell injection and proceeded on a weekly basis for a total of 7 weeks before sacrifice. Group 1 non-injected mice received no tumor therapy. Group 2 mice were used as positive controls and also received no immuno stimulatory therapy. Mice in group 3 received 200 μgm of levamisole, a non-specific immune stimulator. Group 4 mice were given 300 μgm of heat and formalin killed Corynebacterium parvum which is known to non specifically stimulate macrophage populations. Mice in group 5 received unblocked lymphocytes at a concentration of 4 x 106 cells/ mouse. Group 6 mice received a combination therapy of levamisole, C. parvum and unblocked lymphocytes. Weekly measurements of tumor volume were made using vernier calipers. At the time of sacrifice specific cytotoxicity tests were performed. These included the antibody-dependent cell-mediated cytotoxicity (ADCC) test, the blocking factor (BF) assay and the cytolytic T-lymphocyte (CTL) test. The lymphocyte transformation test using phytohemagglutinin, a T-cell mitogen, was also performed at the time of sacrifice, using mouse spleen cells. Levamisole was unable to significantly stimulate the immune status of group 3 animals and showed no apparent benefit in reducing tumor volume. Unblocked lymphocytes administered to group 5 mice may have had some stimulatory effect upon the immune status of the tumor mice, but it was not significant. Tumor volume was the greatest for group 5 mice and significantly higher than for those mice treated only with C. parvum (group 4) or the combination therapy (group 6). ADCC and BF cytotoxicity results did tend to indicate that C. parvum alone and in combination with levamisole and unblocked lymphoctyes was able to stimulate the immune responses, of group 4 and 6 animals. Tumor volumes were the lowest for these 2 groups. Combination group 6 mice had the lowest tumor incidence also. It was concluded from this study that the combination of levamisole, C. parvum and unblocked lymphocytes did have an enhancing effect upon the immune status of tumor hosts, which may actually aid in lowering tumor incidence and progression

Mean Sea Level Changes in the Southwestern Baltic Sea Over the Last 190 Years

(First paragraph) Over the 20th century a global mean sea level (GMSL) rise of about 1.3 to 2 mm/yr could be observed and it is projected to further accelerate throughout the 21st century (Church and White 2006, Hay et al., 2015; Dangendorf et al., 2017). However, GMSL rise is neither temporally nor spatially uniform. Because of a number of different factors (e.g. mass changes and gravitational effects due to melting ice sheets/glaciers, expanding/contracting volume due to temperature and salinity fluctuations, ocean circulation changes, atmospheric forcing), regional mean sea level (MSL) trends can vary significantly from the global average. In order to develop sustainable coastal protection strategies, local/regional sea level studies are necessary