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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Model Theory Of Derivation Spaces

Kasal, Ozcan 01 February 2010 (has links) (PDF)
In this thesis, the notion of the derivation spaces is introduced. In a suitable two-sorted language, the first order theory of these structures is studied. In particular, it is shown that the theory is not companionable. In the last section, the language is expanded by predicate symbols for a dependence relation. In this language it is shown that the extension of the corresponding theory has a model companion. It is shown that the model companion is a complete, unstable theory which does not eliminate quantifiers.
42

The physical and emotional benefits of companion animals

Tietjen, Holli Marie 30 October 2006 (has links)
Elderly people are at high risk for conditions associated with inactivity, and lack of motivation is an important factor contributing to this inactivity. It is believed that a dog can provide the necessary motivation to get a senior citizen up and moving because it needs attention as well as someone to feed it and take it for walks. The objective of this five-week prospective cohort study was to determine if registered therapy dogs made available for informal visits to a cohort of retirement community elderly would motivate the subjects to increase their activity levels by comparing the number of steps taken in the presence of the exposure (opportunity to visit with dog) versus steps taken when unexposed (no opportunity to visit with dog). A secondary objective was to measure possible improvements in mental and physical health scores over the course of the study. The steps were measured each week with a pedometer and the happiness and depression scores were obtained through a questionnaire given at the beginning and at the end of the study. Twenty subjects agreed to participate, and there was an increasing trend in the number of steps over calendar weeks, but not an increase with exposure level (number of dog-visits). Happiness (p = .53) and depression (p = .083) scores did not significantly change during the study. Increased step counts each week may have been associated with other motivating factors such as competition among residents and individual desire to achieve higher counts each week.
43

Äldre och teknologiska hjälpmedel : interaktionsmönster som metod för att studera hur teknik i framtiden kan användas inom äldreomsorgen.

Ahlén, Björn January 2005 (has links)
<p>Ny teknologi har skapat nya möjligheter inom utvecklingen av teknologi för äldre. Kunskap behövs om de äldres behov och vilka situationer i vardagen som skulle kunna underlättas av teknik för att minska de äldres beroende av andra människor. I utvecklingen av ett interaktivt teknologiskt hjälpmedel en så kallad virtual companion har en etnografisk studie gjorts för att kartlägga vardagen på ett äldreboende och interaktionen mellan vårdgivare och vårdtagare. Dessa har strukturerats upp i interaktionsmönster för att bli ett underlag till funktioner som skall implementeras i hjälpmedlet.</p>
44

Yield, pest density, and tomato flavor effects of companion planting in garden-scale studies incorporating tomato, basil, and brussels sprout

Bomford, Michael K. January 2004 (has links)
Thesis (Ph. D.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xiii, 108 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 93-99).
45

Intercropping in corn : soil physical quality and soil inorganic nitrogen levels

Melkamu, Teshome. January 1996 (has links)
Monoculture corn (Zea mays L.) production may result in increased soil degradation through intensive cultivation and N fertilizer use. Intercropping may reduce these negative effects. The objectives of the study were to examine at two sites the effects of monocropping and intercropping corn on soft physical and chemical properties. A sandy loam soil of the Chateaugay series and a sandy loam soft of St Dainase series were used in a field experiment for 1993 and 1994 growing seasons. Soil with corn monoculture planted at 60 and 90 cm row width had lower soil, organic matter than that under intercrops. Soil aggregate stability treatment effects varied with soil. Corn intercropped with perennial rye grass (Lolium perenne L.) showed the highest of aggregate stability. Similar trends were noted with wet-sieved aggregate diameters. Monoculture corn tended to produce higher soil bulk density than intercrops. There was some evidence of compaction after late seeding of intercrops. Monoculture corn resulted in more acidity and lower pH than corn with intercrops. Extractable P and K by Mehlich III were lower in monoculture corn than corn-soybean intercrops. Intercropping tended to reduce residual soil NO3 -- levels but this effect varied with depth. Single and broadcast N application resulted in higher N residues with corn planted at 75 cm row width than split and banded application. Intercropping tended to reduce soil degradation and pollution as measured by aggregate stability and NO3 -- residues.
46

Intercropping corn (Zea mays L.) with forage legumes to suppress yellow nutsedge (Cyperus esculentus L.)

Armour, Ian January 1989 (has links)
A two year study was conducted to investigate the effect of intercropping corn with alfalfa or red clover with or without an initial application of the herbicide EPTC$ sp+$ (S-ethyl dipropylthiocarbamate + R-25788 antidote) on the weed yellow nutsedge (Cyperus esculentus L.). EPTC$ sp+$ applied prior to crop seeding in 1984 significantly reduced yellow nutsedge shoot growth in the first year but did not significantly reduce tuber populations. EPTC$ sp+$ significantly improved corn silage and grain yield and alfalfa establishment in the first year but did not significantly improve red clover establishment. In the second year, a trend of superior forage legume establishment and lower yellow nutsedge shoot production was observed in those treatments established the previous year with EPTC$ sp+$. Over the two year period, yellow nutsedge tuber populations in treatments established with EPTC$ sp+$ were significantly greater in the monocropped corn treatment than in any other treatment. In treatments established without a herbicide, yellow nutsedge tuber populations were also greatest in the monocropped corn treatment.
47

Effets des cultures intercalaires dans le maïs-grain, sur le rendement en grain, la qualité édaphique, et la teneur en azote inorganique des sols

Claude, Pierre-Phillippe January 1990 (has links)
The objectives of the study were to determine whether intercropped alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.) or rye grass (Lolium multiflorum Lmk.) could simultaneously contribute to the nitrogen regime of grain-corn (ie: increased yield), improve edaphic quality, and decrease the level of inorganic nitrogen present in the soil after corn harvest. To achieve these objectives the seeding of the intercrops was delayed, the corn population was increased, and the red clover was spring-ploughed. / Fall-ploughed red clover maintained the mean weight diameter (MWD) of aggregates on the Ste-Rosalie clay. Spring-ploughed red clover on the other hand caused a decrease in bulk density in the top 10 cm of the Chicot loam. / The nitrogen-response of corn indicated that the intercrops did not contribute to the nitrogen regime of grain-corn. There were also indications that intercrops competed with corn for available inorganic nitrogen and water. The intercrops, however, did reduce the levels of soil inorganic nitrogen in the fall allowing for a possible decrease in the nitrogen load of soil percolates. / Despite the beneficial effect of nitrogen fertilisation on the organic nitrogen content of the soil, the presence of leguminous intercrops did not prevent the increase of the soil CN ratio.
48

Use of perennial leguminous living mulches for the fertilization of broccoli in an organic agriculture system

Thériault, Frédéric. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Plant Science. Title from title page of PDF (viewed 2008/12/09). Includes bibliographical references.
49

Next-generation distillers dried grain as a potential dietary ingredient in dog and cat diets

Smith, Spencer C. January 1900 (has links)
Master of Science / Department of Grain Science and Industry / C.G. Aldrich / Novel ingredients have been a source of innovation and growth in the pet food market. Further, with rising trends in the humanization of pet food, there has been increased competition between the human food systems and pet food industry for high quality ingredients. Next-generation distillers dried grains (NG-DDG) are a sustainable alternative protein source that show a strong potential for use in companion animal diets. The objectives of this work were to determine the effect of NG-DDG on the extrusion of dry kibbles, the utilization of diets by dogs, the palatability of diets by dogs and cats, and to evaluate the amino acid profile and protein quality through a chick growth assay. Corn gluten meal (CGM) and soybean meal (SBM) were used as standards for comparison. Diets were extruded over 3 days in a complete block design. During extrusion, the NG-DDG kibbles had less radial expansion (P<0.05) compared to the CGM and SBM kibbles (2.62 vs. average 3.10 mm²/mm², respectively). The NG-DDG kibble also required a smaller (P<0.05) mass restriction-valve opening to increase die back-pressure. No other differences in extrusion parameters or kibble texture were observed. Twelve beagle dogs were arranged in a 3x3 replicated Latin Square and were each fed the 3 experimental diets to evaluate digestibility by use of titanium dioxide. Diet produced with CGM was more digestible (P<0.05) in terms of dry matter, organic matter, crude protein, crude fat, and gross energy. Additionally, dogs fed NG-DDG diets had larger (P<0.05) fecal mass than both CGM and SBM (55.65 vs 35.91 and 43.25 g/d, respectively), and a higher (P<0.05) fecal score than dogs fed the CGM diet (3.63 vs. 3.27). Diets were fed to both dogs and cats to assess palatability via a two-bowl test. Dogs had a preference (P<0.05) for CGM over SBM and NG-DDG, but cats showed a preference (P<0.05) for SBM and NG-DDG over CGM. To assess protein quality, one-day old chicks (CobbxCobb; n=120) were fed semi-purified diets containing test ingredients at a 10% crude protein inclusion level, as well as spray dried granulated egg (SDG) and a nitrogen-free basal diet (NEG) to serve as positive and negative controls, respectively. Chicks were arranged in a randomized block design with 6 chicks per pen, 1 pen per battery, and 4 pens per treatment. The protein efficiency ratio (PER) of each treatment was calculated as weight gain (g) per protein intake (g). All experimental treatments had a lower (P<0.05) PER value than the positive control. The PER for NG-DDG and CGM did not differ from each other and had the lowest value of all treatments (P<0.05; average 1.17). In summary, next-generation distillers dried grains can be used to make a similar kibble to CGM and SBM, are similar to SBM in terms of digestibility, and would be an acceptable source of protein in companion animal diets when paired with a supplemental protein source.
50

The effects of natural antioxidants on the stability of omega-3 fatty acids in dog food

Glodde, Florentina 01 May 2017 (has links)
The efficiency of five natural antioxidants (curcumin, cranberry, pomegranate, grape seed extract (GSE) and açai berry) in reducing lipid oxidation in dog food was tested in comparison to the synthetic antioxidant butylated hydroxyanisole (BHA). Lipid oxidation was evaluated after 12 days of storage at 55C and thiobarbituric acid-reactive substances (TBARS) was measured as an indicator of lipid oxidation. In project one, the natural antioxidants were added at 0.2% and BHA at 0.02% of the food (DM basis) and samples were collected on day 12 and analyzed for TBARS. Compared with the control treatment, TBARS values were lower (p<0.01) for four antioxidant treatments (curcumin, cranberry, pomegranate and GSE) but not for the açai berry treatment (p<0.39). The four antioxidants showed similar efficacy at lowering lipid oxidation as BHA and therefore may have the potential to substitute BHA in dog food. In project two, we evaluated the effects of GSE and curcumin at two inclusion rates (0.1 and 0.2% of food DM) on TBARS and omega-3 fatty acid (FA) content over 12 days of storage at 55C. By day 12, our results showed no significant differences in TBARS values between the BHA and the 0.1% GSE treatment, however BHA was still more effective than the 0.1% GSE as the differences in fold increase in TBARS were lower for BHA (19.4%) than for the 0.1% GSE (75.5%) treatment. Omega-3 FA loss tended (P>0.11) to be greater at the lower inclusion rate which correlated with the increased TBARS values at the 0.1% when compared to the 0.2% inclusion rate. Curcumin and GSE were most effective at maintaining omega-3 FA content at the 0.2% inclusion rate and showed no significant differences from the BHA treatment. In conclusion, BHA in dog food can be effectively substituted by GSE, cranberry, curcumin and pomegranate at the inclusion rate of 0.2% of food DM.

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