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Ammonia control best management practices
Full text link"There is growing interest in odor and gaseous emissions from livestock operations because of concern about global warming and enforcement of the Clean Air Act. This bulletin provides and evaluates best management practices for the control of ammonia lost to the air on dairy farms. Benefits are based on an approximation of ammonia emissions using currently available information. There are likely to be significant variations with region of the country, climate, and management of the dairy cattle housing system."--P. 1.Reviewed August 2009. Reviewed December 2013. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalogKeywords: livestock dairy operations, ammonia contro
Oregon State Forester ; Vol. 12, No. 1 (January 1959)
No full textMagazine of the OSC Oregon Forestry Alumni Association.Keywords: High School Contact Program, UW Pack Forest, Enrollment Statistics, H.I. Nettleton, European Forestry Tour, With The Classes, McDonald-Adair Report, Forestry Research, OSC UW Branch, 1958 European Industrial Forestry Repor
The Davey-Stewartson equations : a numerical study
Full text linkIn 1974 Davey and Stewartson used a multi-scale analysis to derive a coupled
system of nonlinear partial differential equations which describes the evolution of a
three dimensional wave packet in water of a finite depth. This system of equations
is the closest integrable two dimensional analog of the well-known one dimensional
nonlinear Schrodinger equation. The method of inverse scattering can thus be used
to solve the Davey-Stewartson equations in theory, but in practice this method is
not feasible with arbitrary initial conditions. In this thesis we present a numerical
method for solving the Davey-Stewartson equations. It is an extension of the split-step
Fourier method that proved to be so successful for the nonlinear Schrodinger
equation. This method is tested on some known soliton and dromion solutions and
then used to study modulational instability and solutions which become singular in
finite time
High Pressure Effects on Proteolytic and Glycolytic Enzymes Involved in Cheese Manufacturing
Full text linkThe activity of chymosin, plasmin, and Lactococcus
lactis enzymes (cell envelope proteinase, intracellular
peptidases, and glycolytic enzymes) were determined
after 5-min exposures to pressures up to 800 MPa.
Plasmin was unaffected by any pressure treatment.
Chymosin activity was unaffected up to 400 MPa and
decreased at 500 to 800 MPa. Fifty percent of control
chymosin activity remained after the 800 MPa treatment.
The lactococcal cell envelope proteinase (CEP)
and intracellular peptidase activities were monitored
in cell extracts of pressure-treated cells. A pressure
of 100 MPa increased the CEP activity, whereas 200
MPa had no effect. At 300 MPa, CEP activity was
reduced, and 400 to 800 MPa inactivated the enzyme.
X-Prolyl-dipeptidyl aminopeptidase was insensitive
to 5-min pressure treatments of 100 to 300 MPa, but
was inactivated at 400 to 800 MPa. Aminopeptidase
N was unaffected by 100 and 200 MPa. However, 300
MPa significantly reduced its activity, and 400 to 800
MPa inactivated it. Aminopeptidase C activity increased
with increasing pressures up to 700 MPa.
High pressure did not affect aminopeptidase A activity
at any level. Hydrolysis of Lys-Ala-ρ-NA doubled
after 300-MPa exposure, and was eliminated at 400
to 800 MPa. Glycolytic enzyme activities of pressure-treated
cells were evaluated collectively by determining
the titratable acidity as lactic acid produced by
cell extracts in the presence of glucose. The titratable
acidities produced by the 100 and 200 MPa samples
were slightly increased compared to the control. At
300 to 800 MPa, no significant acid production was
observed. These data demonstrate that high pressure
causes no effect, activation, or inactivation of proteolytic
and glycolytic enzymes depending on the pressure
level and enzyme. Pressure treatment of cheese may alter enzymes involved in ripening, and pressure-treating
L. lactis may provide a means to generate
attenuated starters with altered enzyme profiles.Keywords: protease, cheese ripening, Lactococcus, peptidaseKeywords: protease, cheese ripening, Lactococcus, peptidas
Fresh Fish Attributes and Consumers’ Preference Ranking in Rural and Urban Households in Ondo State, Nigeria
Full text linkThe study investigated fresh fish characteristics that determine consumers' preference for fresh fish in rural and urban households. Primary data were collected from a total of 192 fresh fish consumers using multi-stage sampling procedure. The data were analyzed using descriptive statistics, regression analysis and Relative Attribute Model (RAM). The results showed that an average sampled respondent was literate with mean household size of 5. The average age of respondents was 35years, while the average monthly income of household was N34,240 (urban) and N26,880 (rural). Empirical result revealed that urban households consumed more catfish than other fish species owing to possession of certain attributes, availability and price. Also, rural households consumed more fresh fish than urban households because of cheaper price occasioned by proximity to riverine areas where fishing is the predominant occupation. Regression results revealed that sweetness, extent of boniness and cheapness were more significant than other attributes in influencing preference ranking. Also, the preference for fresh fish was found to be more significant in determining consumers' monthly expenditure on fresh fish. The relative importance of the individual fresh fish attributes revealed that boniness and sweetness took leading positions in consumer preference ranking in both rural and urban households. It is concluded that consumers of fresh fish look out for certain characteristics which differ in their ability to influence consumers' motivation to make purchase decisions. It is recommended that fresh fish sellers watch out for these attributes for rapid turnover and profitable fish marketing business.Keywords: Markets and Trade, Fisheries Economics, Markets: Preferences and PricesKeywords: Markets and Trade, Fisheries Economics, Markets: Preferences and Price
Associations between Mycobacterium avium subsp. paratuberculosis antibodies in bulk tank milk, season of sampling and protocols for managing infected cows
Full text linkBACKGROUND: The objective of this study was to identify associations between the concentration of Mycobacterium avium subsp. paratuberculosis (MAP) antibodies in bulk milk and potential risk factors in herd management and herd characteristics, explaining high MAP antibody titers in milk. An extensive questionnaire was administered to 292 organic and conventional dairy farms from New York, Wisconsin and Oregon. Bulk milk samples were taken from each farm for MAP enzyme-linked immunosorbent assay (ELISA). A general linear model was constructed with MAP ELISA value as the outcome variable and the management factors and herd characteristics as independent variables, while at the same time controlling for the study design variables of state, herd size, and production system (organic or conventional). High bulk tank MAP ELISA value may be due to either a high prevalence of MAP in a herd with many cows contributing to the antibody titer or due to a few infected cows that produce large quantities of antibodies. RESULTS: Results of the regression models indicated that bulk milk ELISA value was associated with season of sampling and the presence or absence of protocols for managing MAP-positive cows. The concentration of MAP antibodies in bulk milk varied seasonally with a peak in the summer and low concentrations in the winter months. When compared to farms that had never observed clinical Johne’s disease, keeping MAP-positive cows or only culling them after a period of delay was associated with an increase in optical density. CONCLUSIONS: The seasonal variation in MAP antibody titers, with a peak in the summer, may be due to a seasonal increase in MAP-bacterial load. Additionally, seasonal calving practices may contribute to seasonal fluctuations in MAP antibody titers in bulk tank milk. Keeping MAP-positive cows increases the antibody titer in bulk milk, likely due to direct antibody production in the infected cow and indirect triggering of antibody production in herdmates.Keywords: Antibodies, ELISA, Cattle, Mycobacteirum avium subsp. paratuberculosis, Bulk-tank milkKeywords: Antibodies, ELISA, Cattle, Mycobacteirum avium subsp. paratuberculosis, Bulk-tank mil
Short-Term Butterfly Response to Sagebrush Steppe Restoration Treatments
Full text linkAs part of the Sagebrush Steppe Treatment Evaluation Project (SageSTEP), butterflies were surveyed pre-treatment and up to four years post-treatment at 16 widely distributed sagebrush steppe sites in the interior West. Butterfly populations and communities were analyzed in response to treatments (prescribed fire, mechanical, herbicide) designed to restore sagebrush steppe lands encroached by pinyon-juniper woodlands (Pinus, Juniperus spp.) and invaded by cheatgrass (Bromus tectorum). Butterflies exhibited distinct regional patterns of species composition, with communities showing marked variability among sites. Some variation was explained by the plant community, with Mantel's test indicating that ordinations of butterfly and plant communities were closely similar for both woodland sites and for lower elevation treeless (sage-cheat) sites. At woodland sites, responses to stand replacement prescribed fire, clear-cutting, and tree mastication treatments applied to 10–20-ha plots were subtle: 1) no changes were observed in community structure; 2) Melissa blues (Plebejus melissa) and sulfurs (Colias spp.) increased in abundance after either burning or mechanical treatments, possibly due to increase in larval and nectar food resource, respectively; and 3) the juniper hairstreak (Callophrys gryneus) declined at sites at which it was initially present, probably due to removal of its larval food source. At sage-cheat sites, after prescribed fire was applied to 25–75-ha plots, we observed 1) an increase in species richness and abundance at most sites, possibly due to increased nectar resources for adults, and 2) an increase in the abundance of skippers (Hesperiidae) and small white butterflies. Linkages between woody species removal, the release of herbaceous vegetation, and butterfly response to treatments demonstrate the importance of monitoring an array of ecosystem components in order to document the extent to which management practices cause unintended consequences.Keywords: prescribed fire, cheatgrass, mowing, pinyon-juniper, mastication, cut and leave, insect–plant relationsKeywords: prescribed fire, cheatgrass, mowing, pinyon-juniper, mastication, cut and leave, insect–plant relation
Community based fishery management in Hyogo Prefecture, Seto Inland Sea
Full text linkSeto Inland Sea plays a significant role in Japanese coastal fisheries. The successful development coastal community based fishery management contributes in sustainable fisheries. Hyogo Prefecture has a long history of coastal fisheries and has been selected as the study site. Community based fishery management in Japan reduce monitoring and enforcement cost. Fishermen comply rule and regulation settled by them, bottom up not top down. Participation from fishermen in adopting fishery management plan is the key factor. There can be transaction costs involve in adopting the Fisheries Coordination Scheme. Nevertheless this can be paid off by the long run benefit from the greater resource abundance and the optimum utilization of the available fishery resources. Fishermen can equally participate in community fishery management through being member of corresponding fishery cooperative. They have the common goal of optimum utilization fishery resource. The fishing right granted to fishery cooperative is fairly distributed among the members, transparently. System of election at each step supports this factor of equity. Coastal fisheries in Seto Inland Sea - Hyogo Prefecture is sustainable. Fishermen collaborate in maintaining the ecological system (example is the management in Sika-no-Se Area) and sustainable fishery development. This is mainly due to the granted fishing right, equity in right sharing system, and effective coordination among stakeholders.Keywords: coastal fisheries, community based fishery management, Fisheries Management for Coastal Fisheries, Seto Inland Sea, Fisheries EconomicsKeywords: coastal fisheries, community based fishery management, Fisheries Management for Coastal Fisheries, Seto Inland Sea, Fisheries Economic
BartholomewJerriMicrobiologyEffectsWaterVelocity.pdf
No full textCeratomyxa shasta is a myxozoan parasite identified as a contributor to salmon mortality in the Klamath River, USA. The parasite has a complex life cycle involving a freshwater polychaete, Manayunkia speciosa and a salmonid. As part of ongoing research on how environmental parameters influence parasite establishment and replication, we designed a laboratory experiment to examine the effect of water flow (velocity) on completion of the C. shasta infectious cycle. The experiment tested the effect of two water velocities, 0.05 and 0.01 m/s, on survival and infection of M. speciosa as well as transmission to susceptible rainbow trout and comparatively resistant Klamath River Chinook salmon. The faster water velocity facilitated the greatest polychaete densities, but the lowest polychaete infection prevalence. Rainbow trout became infected in all treatments, but at the slower velocity had a shorter mean day to death, indicating a higher infectious dose. Infection was not detected in Chinook salmon even at a dose estimated to be as high as 80,000 actinospores per fish. The higher water velocity resulted in lower C. shasta infection prevalence in M. speciosa and decreased infection severity in fish. Another outcome of our experiment is the description of a system for maintaining and infecting M. speciosa in the laboratory
Retrieval of cloud droplet size from visible and microwave radiometric measurements during INDOEX: Implication to aerosols’ indirect radiative effect
Full text linkThe effective radius of water cloud droplets is retrieved using remotely sensed passive microwave and visible data collected by aircraft during the Indian Ocean Experiment. The purpose of this study is to assess the aerosols’ effect on cloud microphysical and radiative properties. To study this effect, we investigate the relationships among effective radius, liquid water path and number concentration of cloud droplets. The effective radius retrieval uses imager observations of reflected sunlight at 0.64 mm and liquid water path derived frommicrowave measurements. Results of an error analysis show that retrieval error is the largest for thin clouds having small visible reflectances and small liquid water path. For this reason, only pixels with visible reflectances greater than 0.2 are used in our data analysis, so that the maximum RMS error in effective radius is limited to about 4 mm. The relation between liquid water path and effective radius is examined for four different latitudinal regions. Results show that for the same liquid water path, effective radii are significantly smaller in the north than in the south, in correspondence to the north-south gradient of aerosol concentration in this region. In situ aircraft observations reveal larger cloud droplet number concentrations in the north than in the south. The north-south gradient of these variables are consistent with the aerosols’ effect on cloud microphysics, that is, higher aerosol concentration increases the number concentration of cloud droplets, which, in turn, reduces droplet sizes given the same liquid water path and cloud thickness. Results based on comparison between data collected from northern and southern hemispheres suggest that the increase in aerosol number concentration alters cloud droplet numbers and sizes while leaving liquid water contents approximately the same.Keywords: aerosol indirect effect, liquid water path, Indian Ocean Experiment, cloud effective radiusKeywords: aerosol indirect effect, liquid water path, Indian Ocean Experiment, cloud effective radiu