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Implementation of marker-assisted selection for lodging resistance in pea breedingZhang, Chunzhen 30 August 2004 (has links)
Pea populations derived from ten crosses were scored by coupling phase linked sequence characterized amplified region (SCAR) markers A001 and A002, and repulsion phase linked SCAR marker A004 for lodging resistance during the F2 generation. The objective of this project was to test the efficiency of implementation of these three SCAR markers in marker-assisted selection (MAS) for lodging resistance in pea breeding.
Chi-square tests showed that A001 and A004 followed a two independent gene segregation model in all of the eight populations that segregated for these two markers. In the F3 field trial, the differences between mean lodging score of A001 (DNA band present) and a001 (DNA band absent) classes varied from -0.5 to -0.9 with an average of -0.6, based on a 1 to 9 lodging scale, across the eight populations surveyed. The differences between mean lodging score of a004 (DNA band absent) and A004 (DNA band present) classes varied from -0.4 to -1.1 with an average of -0.7, across the eight populations surveyed. In comparison, when the combination of two markers (A001; a004 vs. a001; A004) was used, lodging score differences varied from -0.7 to -1.5, with an average of -1.0 across the eight populations. T-test results showed that significant differences (P<0.05) in lodging score were observed between A001 and a001 classes in seven out of eight populations, and between A004 and a004 classes in six out of eight populations. Further T-tests showed that significant lodging differences were observed among the four classes of the A001 and A004 marker combination in seven out of eight populations assessed, including differences at P<0.01 level in six populations. The greater differences among marker combination classes than between individual marker classes showed that combining two markers was more effective than use of each marker alone in MAS. The marker combination explained (R2) 19-57% of lodging and 4-43% of plant height variation in the eight populations surveyed. The high temperature and potential nitrogen leaching in the summer of 2003, reduced plant growth and lodging. Under optimal growth conditions, differences in lodging between resistant and susceptible cultivars could have been greater.
Five new markers generated by simple sequence repeat (SSR) primers SAD134, SAB81 and SAD141 were identified in the recombinant inbred line (RIL) population derived from MP1401 × Carneval. The markers generated from primers SAD134 and SAB81 explained 12% and 13% of lodging variation in the RILs, respectively. Primer SAD141 produced three markers which explained 19%, 11% and 25% of lodging variation in the RILs, respectively. Linkage analysis showed that none of the three markers derived from primer SAD141 were allelic. The combination of the three markers from primer SAD141 explained 28% of lodging variation. However, utilization of any of these new markers with A001 and A004 did not substantially increase the proportion of lodging variation being explained. Thus, the new markers have limited potential to improve the efficiency of MAS for lodging resistance in pea breeding.
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Developing conventional and intelligent job aids : a case studyRuyle, Kim E. 30 November 1990 (has links)
Job aids are instruments used on the job to improve
human performance by enhancing the knowledge and/or skills
of performers. Conventional job aids are usually printed
on paper; examples include checklists, recipes, and decision
tables.
Expert systems are computerized job aids which interact
with novices to help solve problems normally reserved for
human experts. Because expert systems emulate human
intelligence, they are sometimes called intelligent job
aids.
The purpose of this study was to extend the body of
knowledge concerning conventional and intelligent job aids.
The intent was to learn what major differences and
similarities exist in the design, development, and
application of conventional and intelligent job aids. If
meaningful differences in the application were found, an
additional aim was to determine why they existed.
Job aids were developed to assist technicians in
diagnosing problems with Robert Bosch electronic fuel
injection systems found on certain John Deere diesel
engines. The job aids were validated and then field tested
by 42 John Deere technicians. Subjects used both job aids
to solve problems with a mock fuel system. The diagnoses
were video-taped for later evaluation, and subjects
proffered their opinions about the job aids through
questionnaires and in interviews.
For this project, the intelligent job aid contained more
textual and graphical content and required significantly
more time and resources to develop. In terms of accuracy
and efficiency, the job aids were comparable. Most users
preferred the intelligent job aid though it required more
time to learn to use than the conventional job aid. The
age, education, or experience of the users did not influence
their opinions of the job aids. However, the order in which
the job aids were used did affect opinions; subjects that
used the conventional job aid prior to the intelligent job
aid were more likely to prefer the intelligent job aid.
Implications for job aid project selection, design, and
application are provided. / Graduation date: 1991
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Exploring the Influence of Functional Status on Older Adults' Social Relationships in Assisted Living CommunitiesSandhu, Navtej K 07 August 2012 (has links)
Social relationships can have considerable influence on physical and mental well-being. AL research suggests that other residents are among the most available social contacts and that co-resident relationships can affect life satisfaction, quality of life, and well-being. Although functional status influences social relationships, research has yet to provide an in-depth understanding of how cognitive and physical function affects co-resident relationships in AL. In this thesis, I present an analysis of qualitative data collected over a one-year period in two diverse settings. The thesis addressed: 1) How does functional status influence co-resident relationships? ; and 2) What factors shape its influence? Analysis was guided by principles of Grounded Theory Method. Coming together and pulling apart signifies the key finding that functional status is multi-directional, fluid, and operates in different ways in various situations and across time. Facility and resident –level factors further affect the influence of functional status on co-resident relationships.
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Mobility with Dignity : - Hästens betydelse för livskvalitén hos skadade brittiska soldater och veteraner / Mobility with Dignity : - Hästens betydelse för livskvalitén hos skadade brittiska soldater och veteranerBarvestad, Kinka, Nilsson, Petra January 2012 (has links)
Syftet med studien var att explorativt undersöka vilken betydelse hästen har för brittiska soldater och veteraner som varit ute i krig och återvänt med någon form av ohälsa. Studiens frågeställningar var: Hur används hästen på Horseback UK som en del i tillfrisknandet för brittiska soldater och veteraner som varit ute i krig? Hur beskriver brittiska soldater och veteraner som varit ute i krig hästens betydelse för livskvalitén? För att besvara frågeställningarna tillämpades en metod som bestod av kvalitativa intervjuer. Intervjuerna utfördes på Horseback UK i Skottland som är en välgörenhetsorganisation, skapad för att ge en trygg och säker miljö. De arbetar med hjälp av hästar för att hjälpa de som tjänstgör eller tjänstgjort i den brittiska armén och kommit tillbaka med någon form fysisk eller psykisk ohälsa. Undersökningsgruppen bestod av sju individer, fem var soldater eller veteraner och två var grundarna till organisationen. Resultatet av denna studie visar att samtliga soldater och veteraner var överens om att deras livskvalité har förbättrats efter att hästen kom in i deras liv och att den har haft en viktig betydelse för dem. Exakt hur hästen påverkar just livskvalitén går dock inte att förklara.
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Investigation of Metal-assisted Si Etching for Fabrication of Nanoimprint Lithography StampsAnokhina, Ksenia January 2010 (has links)
This diploma thesis deals with the investigation of the metal-assisted catalytic etching (MaCE) of Si. One of the main goals is to study fabrication of stamps for nanoimprint lithography using MaCE. Formation of nanoporous silicon (PSi), Si nanowires (SiNWs) and three-dimensional nanostructures in Si by MaCE is demonstrated. For this purpose optical lithography, electron beam lithography (EBL), shadow mask evaporation and aerosol nanoparticles deposition techniques have been utilized. The etching rate and surface morphology of Si (with Au lift-off films as a catalyst) as functions of time and concentrations of chemicals are measured in the current diploma work using optical microscope and scanning electron microscopy (SEM). In the current thesis it is shown that Si structures with sub-150 nm lateral sizes, high aspect ratio (up to 1:21), well-defined shapes, and various complexity can easily be fabricated by means of MaCE process.
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Effect of Machining Parameters in Vibration-Assisted Micro GrindingHu, Yung-ming 07 September 2010 (has links)
Cutting fluids have some drawbacks, like health hazards, extra manufacturing cost and environmental contamination. To decrease the disadvantages of using cutting fluids, conventional cutting is a better choice. However, conventional cutting has no advantages of using cutting fluids, such as lubrication. Therefore, vibration assisted cutting (VAC) is a new technology to achieve both purposes of the above machining techniques. Hence, the goal of this study focuses on the mechanical performance of vibration assisted grinding (VAG) for micro grinding of SKD61 steel based on tool life and surface finish.
In this study, it is observed that chatter happens under VAG in the condition of feed 5.76 £gm/rev. Surface roughness (Ra) for the condition of feed 1.92 £gm/rev is better than that of 5.76 £gm/rev. The best surface finish is 0.05 £gm in this study when the feed is 1.92 £gm/rev. Spindle speed does not have significant effect on surface roughness in this study. However, the tool life is short under high spindle speed (35000rpm). Experimental results show that tool life will be prolonged two-thirds for VAG combined with MQL. As changing the amplitude of vibration (for a fixed frequency of 9 kHz) , the larger the amplitude, the better the surface roughness.
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Effect of Machining Parameters in Vibration-Assisted Micro MillingWang, Sheng-Lan 08 September 2010 (has links)
Vibration assisted cutting (VAC) is a new metal machining technique in recent years, where high-frequency and low-amplitude vibrations are imposed to the cutting tool or the workpiece. It has many advantages than conventional cutting (CC), especially improvements in surface finish and tool life. Nowadays, the use of VAC is a good strategy for micro-machining due to long tool life and high product dimension accuracy.
This study presents an experimental investigation of the VAC in micro milling. The tool wear, surface roughness, and burr formation are investigated for different cutting parameters under conventional and vibration assisted cutting. When the vibration speed is higher than 3 times of the cutting speed, the tool life can be prolonged in this study. The experimental results show that VAC process has better surface finish (43.51% reduction in value) compared to that in CC, when the cutting conditions are feed of 4 £gm/rev and cutting speed of 3.39 m/min. It is also found that VAC can diminish the formation of burr formation. By introducing MQL to VAC, the tool life is extended because the MQL could reduce the friction between the tool and workpiece.
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Computer-Assisted Instruction in an Urban School Setting: Fifth-Grade Teachers’ Perceptions and Students' Attitudes Toward ScienceHowell, Leanne 2010 December 1900 (has links)
The purpose of this dissertation study was to investigate a specific computer-assisted instructional software, Study Hall 101, in fifth-grade science. The study was conducted on an urban, elementary school campus in a northeastern school district in Texas. A mixed-methods approach was utilized in an attempt to understand two teachers’ perceptions about its use in fifth-grade science and evaluate its impact on fifth-grade students’ attitudes toward science.
The first inquiry employed a qualitative research design in an attempt to understand teachers’ perceptions towards the use of Study Hall 101. Data collection methods used in this study included interviews, focus groups, and electronic-mail (e-mail) responses to open-ended sentence stems. Four favorable themes emerged from teachers’ responses: (1) students' attitudes toward science, (2) students’ participation in science class discussions, (3) content individualization, and (4) students’ engagement. Teachers’ frustrations also emerged into themes: (1) time constraints, (2) technology glitches, and (3) specific design elements.
The second inquiry employed a quantitative research design in an attempt to investigate the impact of Study Hall 101 on seventy fifth-grade students’ attitudes toward science after an eight-week period. The Modified Attitudes Toward Science Inventory (mATSI) was used for data collection and was administered to students on two occasions, before and after treatment. Results indicated no statistically significant change in fifth-grade students’ overall attitudes toward science as a result of its use; however, two statistically significant findings did occur when data were analyzed across attribute variables of gender, ethnicity, and economic status, as well as specific domains within the mATSI. First, the use of Study Hall 101 was associated with males’ and females’ attitudes in opposite ways in regard to one domain of the mATSI: self-concept toward science. Second, students in the control group experienced a decline in another attitude domain of the mATSI: desire to do science.
The results of this study contribute to the field of K-12 education as we search for effective educational tools to reach diverse student populations. This study concludes that teachers’ perceptions of this software are favorable and that its use in fifth-grade science should be considered as a tool to engage students in their own learning process.
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Low-loss thin film by ion-assisted E-beam depositionLu, Meng-Jen 13 July 2006 (has links)
Due to the fast expansion and development in the optical communication industry, the demand for the film quality has correspondingly increased. Ion beam sputter deposition (IBSD) achieves the lowest loss, but low throughput. In our Lab., E-beam system was used for CaO, MgO and Cr2O3 evaporation on the circumference of the Cr:YAG crystal fiber. Although the substrate was heated to around 275oC, the thin film didn¡¦t achieve low loss and high laser-induced damage threshold film. Adding ion-beam assisted deposition (IAD) system to enhance the thin film energy and packing density is the main theme of this thesis.
The thesis mainly focuses on the characteristics of TiO2 and SiO2 thin film based on E-beam with IAD system. Spectrometer analyzer and Macleod software were used to calculate the refractive index and extinction coefficient. ESCA (electron spectroscopy for chemical analyzer) was adopt to measure the thin film composition of Ti, Si, O. SEM (scanning electron microscope) was used to observe the thin film quality. Low loss and high laser-induced damage threshold thin film are the goal of the present research. With optimized parameters, the refractive index of TiO2 film was achieved to be 2.51 at 500 nm, and the extinction coefficient was less than 2x10-4. The refractive index of SiO2 film can be achieved to be 1.466 at 500 nm, and the extinction coefficient was less than 1x10-4. An HR (R>99.83%) coating at 1233 nm was successfully demonstrated by the IAD deposition system.
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The systematic use of sound in multimedia instruction to enhance learning /Bishop, Mary Jean, January 2000 (has links)
Thesis (Ed. D.)--Lehigh University, 2000. / Includes vita. Includes bibliographical references (leaves 120-152).
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