• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 6231
  • 1792
  • 1667
  • 750
  • 371
  • 362
  • 336
  • 336
  • 336
  • 336
  • 336
  • 333
  • 240
  • 228
  • 201
  • Tagged with
  • 15028
  • 2049
  • 1443
  • 1199
  • 960
  • 873
  • 770
  • 654
  • 631
  • 546
  • 529
  • 518
  • 512
  • 510
  • 481
  • 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.
71

The actions and interactions of noradrenaline, dopamine and L-dopa

Lazner, Margaret Ann January 1975 (has links)
1 v. (various paging) : ill. ; 26 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1976) from the Dept. of Human Physiology and Pharmacology, University of Adelaide
72

Thermal characterization of a Hall Effect thruster /

Bohnert, Alex M. January 2008 (has links) (PDF)
Thesis (M.S. in in Aeronautical Engineering)--Air Force Institute of Technology, March 2008. / "Presented to the Faculty, Department of Aeronautics and Astronautics Graduate School of Engineering and Management, Air Force Institute of Technology Air University, Air Education and Training Command in partial fulfillment of the requirements for the Degree of Master of Science in Aeronautical Engineering, March 2008."--P. [ii]. Thesis advisor: Dr. William Hargus. "March 2008." "AFIT/GA/ENY/08-M01." Includes bibliographical references. Also available online in PDF from the DTIC Online Web site.
73

Sensitivity analysis of blast loading parameters and their trends as uncertainty increases

Borenstein, Elan. January 2007 (has links)
Thesis (M.S.)--Rutgers University, 2007. / "Graduate Program in Mechanical and Aerospace Engineering." Includes bibliographical references (p. 103-105).
74

Chronic Ethanol Modulated Photic and Non-photic Phase Responses in Syrian Hamster and C57BL/6J Inbred Mouse

Seggio, Joseph A. January 2009 (has links) (PDF)
No description available.
75

Photoperiod and temperature effects on the growth and development of rice (Oryza sativa L.)

Azmi, Abdul Razzaque January 1969 (has links)
The objective of this study was to determine how the rice plant responds to combinations of temperature and photoperiod. Both temperature and photoperiod are important for normal completion of the life cycle, but there has been little study of their combined effects in rice. Controlled temperature and photoperiod experiments were conducted in growth cabinets using 4 temperatures; 35/18, 35/26.5, 35/35 and 40.5/18°C day/night. There were 4 photoperiods of 8, 10, 12 and 14 hours. Light was provided by cool white fluorescent tubes. The day temperature periods corresponded to the photoperiods. Four varieties were selected: Kangni-27 and Dokribasmati from Dokri, Pakistan; Caloro from California, U.S.A.; and Bluebonnet-50 from Texas, U.S.A. Growth characteristics, net photosynthesis rates, and flowering were measured and chlorophyll a and b, carotenoid, carbohydrate and ash concentrations were determined. The effect of photoperiod on flowering was most pronounced at 35/26.5. The delays in flowering at 14 hours for this temperature were 30, 30, 21 and 63 days in Kangni, Caloro, Dokri and Bluebonnet compared to the optimum, photoperiod which varied among varieties. The delays observed at 35/18 were 23, 14, 6 and 2 days. At 35/26.5 all varieties showed a significant photoperiodic effect on flowering, but at 35/18, Dokri and Bluebonnet did not show a significant photoperiodic effect. 35/35 was most unsatisfactory for flowering. A similar but less serious effect was found at 40.5/18. Final dry matter production was high at 35/35 and 40.5/18; an increase of 3 to 8 g per pot was noted at these temperatures compared with 35/26.5 and 35/18. There was an increase of about 5 g per pot at maturity for each increase of 2 hours in photoperiod. Panicle characteristics were generally unaffected by temperature, but there were some photoperiod effects. At the 12-hour photoperiod panicles of all varieties were 2 to 4 cm longer than at other photoperiods and at 10-and 12-hour photoperiods there were 10 to 32 more spikelets per panicle than at 8 and 14 hours. Sterility was very high at 35/35 (95%) and 40.5/18 (69%). Average sterility at 35/18 and 35/26.5 was about 36%. There was 8 to 24% less sterility at 10- and 12-hour photoperiod compared with 8 or 14 hours. Hundred-grain weight was unaffected by photoperiod or temperature. High numbers of tillers were consistently observed at 40.5/18 and 35/18 and low numbers at 35/35. The differences varied with the stage of growth. Plants at 14-hour photoperiod had consistently more tillers than those at other photoperiods. Kangni and Dokri had higher numbers of tillers than Caloro and Bluebonnet. Leaf development was fastest at 40.5/18 and the 12-hour photoperiod. This was especially so at 6 and 8 weeks. Kangni and Dokri had faster development than Caloro and Bluebonnet. Plant height was 2 to 5 cm greater at 2 weeks at 35/26.5 and 35/35 but at 4, 6 and 8 weeks, plant height was greater at 35/18. The shortest plants were observed at 40.5/18. The rate of net photosynthesis on a leaf blade weight basis was highest at 2 weeks in all varieties at all photoperiods and temperatures. The rate generally declined with the aging of plants. The greatest decline at 8 weeks, compared to 2 weeks, was 71% in Dokri and least was 65% in Bluebonnet. Except at 2 weeks, the highest rate of photosynthesis was at 40.5/18 but at 6 and 8 weeks there were also high rates at 35/35. The rate was consistently higher in plants growing in the 8-hour photoperiod. The rate was higher in the 8-hour photoperiod compared to the 14-hour by 28 and 25% at 6 and 8 weeks respectively. Both Caloro and Bluebonnet had higher net photosynthetic rates than Kangni and Dokri. In all varieties chlorophyll and carotenoid content declined with age. Both chlorophyll and carotenoid were high at 40.5/18 at all stages. Chlorophyll concentration was also high at 35/18 at 2, 4 and 6 weeks. A definite correlation between chlorophyll content and photosynthesis was not shown, but there was a significant correlation between chlorophyll and fresh weight at all temperatures and photoperiods except at 2 weeks. Total water soluble carbohydrate and total ash content did not show definite trends according to stages of growth. No relationship could be shown between floral initiation and combined carbohydrate and ash content. / Land and Food Systems, Faculty of / Graduate
76

Temperature effects on the response to sulphur of barley (Hordeum vulgare L.), peas (Pisum sativum L.) and rape (Brassica campestris L.)

Herath, Herath Mudiyanselage Walter January 1970 (has links)
The effects of temperature and sulphur nutrition on the growth, yield and mineral composition (N, NO₃-N, S and SO₄-S) of Hordeum vulgare L. cv Olli, Pisum sativum L. cv Dark Skin Perfection and Brassica campestris L. cv Arlo, were investigated in controlled environments. The net CO₂ exchange rates and compensation points were also determined at two S levels (0 and 64 ppm) under various temperature regimes. When barley and rape plants were grown at 0 ppm S, deficiency symptoms developed in about two weeks, whereas pea plants at the same level developed deficiency symptoms in about three weeks. Plants at the lowest S level and the highest temperature took the shortest time to develop S deficiency symptoms. Fresh and dry weights, shoot length, number of nodes and number of fertile fruit increased with increasing S levels. Shoot growth in all three species was more depressed by S deficiency than root growth. Optimum growing temperature regimes for barley and peas were found to be 24/16 at the vegetative stage and 18/10°C at the mature stage as evident from increased weights, maximum fruit set and mineral uptake. Optimum temperature for rape plants was 29/21°C at both stages of growth. Detrimental effects of cotyledon or endosperm removal tended to mask the effects of temperature and S levels. This method was thus found to be unsatisfactory for the study of S nutrition in plants. Higher mineral concentration was observed at the vegetative stage than at the mature stage in peas and rape plants, while in barley the mineral concentration remained constant at both stages of growth. With increase in S supply there was an increase in uptake of both total S and SO₄-S. Uptake also increased with increasing temperatures. This increase was largely due to "concentration effects". Hence the use of SO₄-S level as a criterion for diagnosis of S deficiency may be unsatisfactory, unless plants are grown at optimum temperatures. S deficient plants had increased total N and NO₃-N concentrations in all three species. NO₃-N concentration also increased with an increase in temperature. The total N concentration did not increase appreciably with temperature. Consequently, at low S level (0 and 8 ppm) total N:total S ratios (N:S) tended to increase or decrease depending on low or high growing temperatures respectively. These changes in ratios were independent of actual size of the plants. Furthermore the ratios for all S levels at the vegetative stage were lower than those at the mature stage. Therefore both temperature and stage of growth are important factors to be considered in interpreting S deficiency from N:S ratios in plants. The net C0₂ exchange rates were generally higher at 20 days than at 30 days. At 0 ppm S level and at high temperature, the decline in net C0₂ exchange rate with age was greater. Maximum CO₂ exchange rates were observed at the optimum growing temperatures for both S levels. Increasing the measuring temperature above the growing temperature caused no further stimulation in CO₂ uptake, and at high temperatures there was a decrease in uptake. When CO₂ exchange rates were measured at two 5.5°C intervals above and below the growing temperatures the maximum rates were recorded at or below growing temperatures in all the species at both S levels. The CO₂ compensation values were higher with lower S level in the leaf tissue than at higher S levels. Increase in growing temperatures also caused larger CO₂ compensation values than at lower temperatures. Negative correlations between CO₂ compensation point and leaf tissue S level and positive correlations between CO₂ compensation point and temperature were observed in barley and peas. / Land and Food Systems, Faculty of / Graduate
77

Die sintese en analise van diuloses en deoksidiuloses met spesiale verwysing na die radiolise produkte van fruktose

Den Drijver, Laetitia 23 September 2014 (has links)
M.Sc. (Chemistry) / Please refer to full text to view abstract
78

Pre-Harvest Glyphosate Effects on Properties of Beta-Glucan from Oat Groats

Alahmed, Abdulrahman January 2019 (has links)
Pre-harvest glyphosate is applied to cereal grains to remove weeds. However, it has been claimed that oat compositions are affected by pre-harvest glyphosate. Research was conducted to evaluate differences in properties of β-glucan in the treated versus untreated oat groats. Two oat cultivars (Rockford and Souris) were grown at Minot and Prosper, North Dakota in 2015, and glyphosate was sprayed during the soft dough stage, physiological maturity stage, or not applied. β-Glucan viscosity was not significantly (p > 0:05) affected by treatment at soft dough or physiological maturity stages. Use of glyphosate at the soft dough stage significantly (p < 0:05) reduced the percentages of β-glucan content and solubility versus untreated samples. Treatment at soft dough and physiological maturity stages significantly (p < 0:05) increased β-glucan molecular weights compared to untreated controls. Therefore, glyphosate can be applied at the physiologically mature stage of grain development because β glucan properties from the groats were not negatively affected.
79

Amphetamine drugs potentiate morphine analgesia in the formalin test

Dalal, Suntanu January 1994 (has links)
No description available.
80

The C.S.I. Effect: Exploration of its Influence on Perception of Criminal Behavior

McConnell, Alexandra 01 December 2014 (has links)
This study explores the C.S.I. effect in relation to its influence on criminal activity. Expansive research exists concerning the C.S.I. Effect, but very little pertains to the influence it has on individuals' perception of crime and their ability to get away with it. The study explores whether heavy viewers of crime show dramas such as Law & Order and C.S.I. display increased confidence in their ability to commit and get away with a crime. Essentially, this study explores whether these crime television shows are not only entertainment, but also may serve as guides on how to commit crimes. Participants in the study were University of Central Florida students. Participants read a description of a crime scene, and provided judgments from the criminal's point of view. They also completed the Crime Drama Viewing Questionnaire and the Levenson Psychopathy Scale in order to explore the possible correlation between reported confidence in "getting away" with criminal activity, type of television viewing, and psychopathy in participants. Using a correlational design, the relation between heavy and light crime drama viewing and criminal activity decision making was examined. The results of this study add to knowledge about how television crime drama potentially increases criminal confidence and competency in criminal behavior.

Page generated in 0.0429 seconds