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Search Results: 1 - 10 of 192741 matches for " Craig G. Cogger "
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Dryland Winter Wheat Yield, Grain Protein, and Soil Nitrogen Responses to Fertilizer and Biosolids Applications
Richard T. Koenig,Craig G. Cogger,Andy I. Bary
Applied and Environmental Soil Science , 2011, DOI: 10.1155/2011/925462
Abstract: Applications of biosolids were compared to inorganic nitrogen (N) fertilizer for two years at three locations in eastern Washington State, USA, with diverse rainfall and soft white, hard red, and hard white winter wheat (Triticum aestivum L.) cultivars. High rates of inorganic N tended to reduce yields, while grain protein responses to N rate were positive and linear for all wheat market classes. Biosolids produced 0 to 1400?kg?ha?1 (0 to 47%) higher grain yields than inorganic N. Wheat may have responded positively to nutrients other than N in the biosolids or to a metered N supply that limited vegetative growth and the potential for moisture stress-induced reductions in grain yield in these dryland production systems. Grain protein content with biosolids was either equal to or below grain protein with inorganic N, likely due to dilution of grain N from the higher yields achieved with biosolids. Results indicate the potential to improve dryland winter wheat yields with biosolids compared to inorganic N alone, but perhaps not to increase grain protein concentration of hard wheat when biosolids are applied immediately before planting. 1. Introduction Biosolids are an effective and relatively safe source of nitrogen (N) for dryland wheat production [1–3]. Applied at agronomic rates, biosolids can supply sufficient N to maximize yield, as well as a host of other nutrients that can benefit crops in a rotational sequence [4, 5]. Determining appropriate agronomic application rates is paramount in balancing nutrient (mainly N) needs of wheat without increasing the risk of nitrate (NO3?) leaching. Considerable research has been devoted to this subject [3, 5]. In the inland Pacific Northwest (PNW) USA, soft white winter wheat is the predominant crop grown on over 2.75 million ha of mainly dryland (rainfed) cropland [6]. The majority of this wheat is exported and used to make unleavened products such as flat breads, noodles, and cakes [7]. Low-grain protein concentration (<10%) is desirable when producing unleavened products. High-grain protein concentration in soft white winter wheat has been a problem in the PNW due, in part, to high soil N levels [7]. Previous biosolids research in this area has shown that agronomic applications at or above rates required to maximize yield may produce undesirably high grain protein concentrations in soft white winter wheat [3, 5]. While high grain protein concentration is detrimental for soft wheat end uses, high protein is desirable in hard red and white winter wheats, with optimum targets of approximately 11.5 and 12.5%,
Estimating Nitrogen Availability of Heat-Dried Biosolids
Craig G. Cogger,Andy I. Bary,Elizabeth A. Myhre
Applied and Environmental Soil Science , 2011, DOI: 10.1155/2011/190731
Abstract: As heat-dried biosolids become more widely produced and marketed, it is important to improve estimates of N availability from these materials. Objectives were to compare plant-available N among three different heat-dried biosolids and determine if current guidelines were adequate for estimating application rates. Heat-dried biosolids were surface applied to tall fescue (Festuca arundinacea Schreb.) in Washington State, USA, and forage yield and N uptake measured for two growing seasons following application. Three rates of urea and a zero-N control were used to calculate N fertilizer efficiency regressions. Application year plant-available N (estimated as urea N equivalent) for two biosolids exceeded 60% of total N applied, while urea N equivalent for the third biosolids was 45%. Residual (second-year) urea N equivalent ranged from 5 to 10%. Guidelines for the Pacific Northwest USA recommend mineralization estimates of 35 to 40% for heat-dried biosolids, but this research shows that some heat-dried materials fall well above that range. 1. Introduction Heat-dried biosolids are convenient to use in a variety of applications. The Class A heat-dried product is suitable as a fertilizer on lawns and gardens as well as for agricultural crops. Heat-dried biosolids are easy to transport and handle and are applied like inorganic fertilizers, except at higher rates. Because a large proportion of the nitrogen (N) in biosolids is in organic form, biosolids act as a slow-release N source, dependent on biological transformation of the organic N into available forms. Accurate estimates of the mineralization rate of biosolids N are critical to developing application rate recommendations that meet plant needs without compromising environmental quality. Smith and Durham [1] used laboratory incubation to compare five different biosolids sources with and without heat drying, and found that the mineralization rates of the heat-dried biosolids were more than double the undried (dewatered only) materials. This rapid mineralization more than compensated for the lower initial ammonium N in the heat-dried biosolids. Rigby et al. [2] observed similar results in a field incubation, estimating mineralizable N from heat-dried biosolids at twice that for dewatered biosolids. Matsuoka et al. [3] and Moritsuka et al. [4] produced heat-dried biosolids in an experimental scale vessel reaching final temperatures of 120 and 180°C. They found increased available N in the 120°C heat-dried biosolids compared with undried biosolids in laboratory incubation and pot studies. Heat drying to a
Comparison of Raw Dairy Manure Slurry and Anaerobically Digested Slurry as N Sources for Grass Forage Production
Olivia E. Saunders,Ann-Marie Fortuna,Joe H. Harrison,Elizabeth Whitefield,Craig G. Cogger,Ann C. Kennedy,Andy I. Bary
International Journal of Agronomy , 2012, DOI: 10.1155/2012/101074
Abstract: We conducted a 3-year field study to determine how raw dairy slurry and anaerobically digested slurry (dairy slurry and food waste) applied via broadcast and subsurface deposition to reed canarygrass (Phalaris arundinacea) affected forage biomass, N uptake, apparent nitrogen recovery (ANR), and soil nitrate concentrations relative to urea. Annual N applications ranged from 600?kg?N?ha?1 in 2009 to 300?kg?N?ha?1 in 2011. Forage yield and N uptake were similar across slurry treatments. Soil nitrate concentrations were greatest at the beginning of the fall leaching season, and did not differ among slurry treatments or application methods. Urea-fertilized plots had the highest soil nitrate concentrations but did not consistently have greatest forage biomass. ANR for the slurry treatments ranged from 35 to 70% when calculations were based on ammonium-N concentration, compared with 31 to 65% for urea. Slurry ANR calculated on a total N basis was lower (15 to 40%) due to lower availability of the organic N in the slurries. No consistent differences in soil microbial biomass or other biological indicators were observed. Anaerobically digested slurry supported equal forage production and similar N use efficiency when compared to raw dairy slurry. 1. Introduction There is a need for a set of best management practices that addresses how to utilize the growing quantity of reactive nitrogen (N) produced by livestock operations. Animal agriculture in the United States has become more specialized with farms consolidating and growing in size [1]. The number of dairy farms has decreased by 94% since 1960, but the number of animals has remained constant [2]. Animal consolidation has created challenges with respect to on-farm N surplus, waste management and nutrient loading in the environment [3, 4]. Annually in the United States, more than 5800?Mg of manure N is produced [5]. One approach to ameliorate negative environmental impacts associated with animal manures is through adoption of anaerobic digestion technologies to treat farm-generated manures and food processing wastes [6–9]. Digestion of wastes can provide a stable and consistent source of nutrients comparable to inorganic fertilizers such as urea. Anaerobic digestion converts organic carbon into methane used to generate electricity, and it also converts organic N to plant available ammonium ( ), increasing the ratio of /total N in the effluent [10]. Carbon is removed during both the methane production and fiber removal processes, resulting in a smaller C?:?N ratio of the effluent [11]. Therefore, digested
The Effects of Old Age on Hepatic Stellate Cells
Alessandra Warren,Victoria C. Cogger,Robin Fraser,Laurie D. DeLeve,Robert S. McCuskey,David G. Le Couteur
Current Gerontology and Geriatrics Research , 2011, DOI: 10.1155/2011/439835
Abstract: Aging is associated with marked changes in the hepatic sinusoid, yet the effect of old age on hepatic stellate cells (HSC) has not been well described. Transmission electron microscopy and immunohistochemistry were used to study the effects of aging on HSC in livers from rats (3-4 mths versus 24–27 mths) and mice (2-3 mths versus 20–22 mths). Desmin-positive HSC doubled in old age in both mice and rats. Alpha-smooth muscle actin- (αSMA-) positive cells did not increase significantly and remained only a small percentage of desmin-positive cells. Electron microscopy revealed that old age is associated with HSC that have a substantial increase in the number of lipid droplets which are larger in diameter. There was also a marked increase of HSC that protruded into the sinusoidal lumen in old mice. In conclusion, old age is associated with hyperplasia of HSC that are not activated and are engorged with lipid droplets.
Critical issues in recent developments in Reformational philosophy: a perspective1
Craig G. Bartholomew
Koers : Bulletin for Christian Scholarship , 1995, DOI: 10.4102/koers.v60i2.628
Abstract: Although the present is a time of great opportunity for Reformational thinking and activity, some Reformational philosophers are proposing a reconstruction of the tradition at the foundational level. Consequently, the present can also he seen as a time of crisis for the tradition as a whole. Proposed shifts are examined in the foundational areas of creation order, the antithesis and the authority of Scripture. These shifts are related to understandings of our context and thus the nature of modernity/postmodernity and its connection to these shifts also receives attention.
Ensemble forecasting with a stochastic convective parametrization based on equilibrium statistics
P. Groenemeijer,G. C. Craig
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2012, DOI: 10.5194/acp-12-4555-2012
Abstract: The stochastic Plant-Craig scheme for deep convection was implemented in the COSMO mesoscale model and used for ensemble forecasting. Ensembles consisting of 100 48-h forecasts at 7 km horizontal resolution were generated for a 2000×2000 km domain covering central Europe. Forecasts were made for seven case studies characterized by different large-scale meteorological environments. Each 100 member ensemble consisted of 10 groups of 10 members, with each group driven by boundary and initial conditions from a selected member from the global ECMWF Ensemble Prediction System. The precipitation variability within and among these groups of members was computed, and it was found that the relative contribution to the ensemble variance introduced by the stochastic convection scheme was substantial, amounting to as much as 76% of the total variance in the ensemble in one of the studied cases. The impact of the scheme was not confined to the grid scale, and typically contributed 25–50% of the total variance even after the precipitation fields had been smoothed to a resolution of 35 km. The variability of precipitation introduced by the scheme was approximately proportional to the total amount of convection that occurred, while the variability due to large-scale conditions changed from case to case, being highest in cases exhibiting strong mid-tropospheric flow and pronounced meso- to synoptic scale vorticity extrema. The stochastic scheme was thus found to be an important source of variability in precipitation cases of weak large-scale flow lacking strong vorticity extrema, but high convective activity.
The Effect of the Small Indian Mongoose (Urva auropunctatus), Island Quality and Habitat on the Distribution of Native and Endemic Birds on Small Islands within Fiji
Craig G. Morley, Linton Winder
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0053842
Abstract: This study investigated the effect of the presence of introduced mongoose, environmental quality and habitat on the distribution of native and endemic birds on 16 small islands within Fiji. In total, 9055 birds representing 45 species were observed within four key habitats (forest, villages, crop land and coastal vegetation) on the 16 islands, half of which had mongoose present. Previous studies attribute bird declines and extirpation anecdotally to the mongoose. The presence of mongoose, environmental quality and habitat type had a measurable influence on observed extant native and endemic bird communities. We conclude that three ground birds; Gallirallus phillipensis, Anas supericiliosa and Porphyrio porhyrio were negatively influenced by the presence of mongoose and that Ptilinopus perousii, Phigys solitarius, Chrysoenas victor, Ducula latrans, Clytorhyrchus vitiensis, Pachycephala pectoralis, Prospeia tabunesis, and Foulehaio carunculata were particularly dependent on good quality forest habitat. Conservation priorities in relation to protecting Fiji's endemic birds from the effect of mongoose are discussed and preventative measures suggested.
Pathogenesis of cerebral malaria—inflammation and cytoadherence
Janet Storm,Alister G. Craig
Frontiers in Cellular and Infection Microbiology , 2014, DOI: 10.3389/fcimb.2014.00100
Abstract: Despite decades of research on cerebral malaria (CM) there is still a paucity of knowledge about what actual causes CM and why certain people develop it. Although sequestration of P. falciparum infected red blood cells has been linked to pathology, it is still not clear if this is directly or solely responsible for this clinical syndrome. Recent data have suggested that a combination of parasite variant types, mainly defined by the variant surface antigen, P. falciparum erythrocyte membrane protein 1 (PfEMP1), its receptors, coagulation and host endothelial cell activation (or inflammation) are equally important. This makes CM a multi-factorial disease and a challenge to unravel its causes to decrease its detrimental impact.
Review of Scott Thumma & Edward R. Gray (Eds.), Gay Religion
Craig This
Journal of Men, Masculinities and Spirituality , 2007,
Abstract: Review of Scott Thumma & Edward R. Gray (Eds.), Gay Religion (Walnut Creek, CA: AltaMira Press, 2004), xvi + 376 pp.
The Relationship between Fenestrations, Sieve Plates and Rafts in Liver Sinusoidal Endothelial Cells
Dmitri Svistounov, Alessandra Warren, Gregory P. McNerney, Dylan M. Owen, Dusan Zencak, Svetlana N. Zykova, Harry Crane, Thomas Huser, Ronald J. Quinn, B?rd Smedsr?d, David G. Le Couteur, Victoria C. Cogger
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046134
Abstract: Fenestrations are transcellular pores in endothelial cells that facilitate transfer of substrates between blood and the extravascular compartment. In order to understand the regulation and formation of fenestrations, the relationship between membrane rafts and fenestrations was investigated in liver sinusoidal endothelial cells where fenestrations are grouped into sieve plates. Three dimensional structured illumination microscopy, scanning electron microscopy, internal reflectance fluorescence microscopy and two-photon fluorescence microscopy were used to study liver sinusoidal endothelial cells isolated from mice. There was an inverse distribution between sieve plates and membrane rafts visualized by structured illumination microscopy and the fluorescent raft stain, Bodipy FL C5 ganglioside GM1. 7-ketocholesterol and/or cytochalasin D increased both fenestrations and lipid-disordered membrane, while Triton X-100 decreased both fenestrations and lipid-disordered membrane. The effects of cytochalasin D on fenestrations were abrogated by co-administration of Triton X-100, suggesting that actin disruption increases fenestrations by its effects on membrane rafts. Vascular endothelial growth factor (VEGF) depleted lipid-ordered membrane and increased fenestrations. The results are consistent with a sieve-raft interaction, where fenestrations form in non-raft lipid-disordered regions of endothelial cells once the membrane-stabilizing effects of actin cytoskeleton and membrane rafts are diminished.
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