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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.
91

Effect of Varenicline vs. Placebo on Reactivity to Tobacco and Alcohol Cues in Smokers who are Light Drinkers

Staios, Gregory 11 January 2011 (has links)
Varenicline is used to treat tobacco dependence. While varenicline decreases craving during a quit attempt, no studies have investigated its effect on cue-induced craving. Varenicline has also been shown to decrease alcohol consumption in animal and humans. This double-blind, randomized, placebo-controlled trial investigated the effect of varenicline on tobacco and alcohol cue-induced craving and alcohol consumption in dependent smokers/light drinkers. Tobacco and alcohol craving were assessed at baseline and after 2-weeks of drug administration using the QSU and ACQ. Significant decreases in cigarette and alcohol craving were observed between the pre- and post-drug session in the varenicline group on QSU Factor 1(87.5811.66 vs.70.5820.79, p=0.008) and ACQ Total (3.371.16 vs. 2.661.15, p=0.004) scores. This effect remained significant after correction for craving during neutral cues in the alcohol but not tobacco condition. No significant decreases in alcohol consumption were seen. These results suggest varenicline decreases overall craving, but not cue-induced craving specifically.
92

Failures to Replicate Hyper-Retrieval-Induced Forgetting in Arithmetic Memory

2013 June 1900 (has links)
Campbell and Phenix (2009) observed retrieval-induced forgetting (RIF) (slower response time) for simple addition facts (e.g., 3 + 4) immediately following 40 retrieval-practice blocks of their multiplication counterparts (3 × 4 = ?). A subsequent single retrieval of the previously unpracticed multiplication problems, however, produced an RIF effect about twice as large for their addition counterparts. Thus, a single retrieval of a multiplication fact appeared to produce much larger RIF of the addition counterpart than did many multiplication retrieval-practice trials. In subsequent similar studies, however, this hyper-RIF effect was not observed (e.g., Campbell & Thompson, 2012). The current studies further investigated hyper-RIF in arithmetic. In Chapter 2 (Experiment 1), composition of operands (unique vs. common) and amount of multiplication practice (6 vs. 20 repetitions of each problem) were manipulated. Participants solved multiplication problems (4 × 7 = ?) and then were tested on their memory for the addition counterparts (4 + 7 = ?) and control additions. Chapter 3 (Experiment 2) attempted an exact replication of Campbell and Phenix. In both studies, hyper-RIF was not observed. The results confirm the basic RIF effect of multiplication retrieval practice on addition counterparts, but cast doubt on the on the reality of the hyper-RIF effect observed by Campbell and Phenix. It is concluded that the hyper-RIF effect reported by Campbell and Phenix is an elusive or non-existent phenomenon; consequently, it cannot at this time be considered an important result in the RIF literature.
93

Experimental and Numerical Analysis of Combined In-line and Cross-flow Vortex Induced Vibration

Yin, Decao January 2013 (has links)
This thesis presents results from experimental and numerical investigations of the hydrodynamic forces on a rigid cylinder moving with prescribed orbits in uniform flow. The hydrodynamic forces are measured in both in-line (IL) and cross- ow (CF) directions. The measurements are processed to nd excitation and added mass coeffcients at discrete frequencies. The numerical simulations are used to illustrate the vortex shedding modes and are compared with the experimental results. The hydrodynamic coeffcients obtained from the harmonic forced motion experiments of a rigid cylinder do not always represent forces on a cross section of a exible beam. The orbits used in the forced motion experiments are therefore extracted from the measured motions of cross sections of a exible pipe under uniform and shear flows. Both periodic and observed orbits within a time window are applied as prescribed motions. Higher order displacement components are present in such orbits. IL response amplitudes from combined IL and CF response are larger than pure IL response amplitudes. The hydrodynamic coefficients obtained from the periodic experiments are often larger than those obtained from the pure IL tests. Higher order displacement components are more common in the IL direction than in the CF direction, and higher order IL displacement components will cause larger hydrodynamic forces in both directions. The hydrodynamic coefficients obtained from periodic motion tests are adequate for representing quasi-periodic observed motions. For chaotic observed motions, periodic orbits will yield hydrodynamic coefficients with larger uncertainties. Results from numerical analyses using large eddy simulation (LES) indicate that this method can be used to identify vortex shedding patterns and predict hydrodynamic forces under certain Re numbers and orbits.
94

Study of Radiation Induced Effects in Semicondutor Devices

Kulkarni, Shrinivasarao R 09 1900 (has links)
Radiation Induced effects
95

A Study on the Coherent Atomic Effects and Their Applications

Sun, Qingqing 2010 May 1900 (has links)
Coherent atomic states prepared by laser field can have quantum interference between the different transition amplitudes. Therefore, the medium susceptibility and optical response can be engineered, leading to many interesting phenomena, such as coherent population trapping (CPT), electromagnetically induced transparency (EIT), and lasing without inversion (LWI). We studied the coherence effects in various prototype atomic systems, and found many interesting applications. We solved the slow light bandwidth problem by decomposing the pulse and matching each frequency to its EIT window using a magnetic field gradient. We also considered the probe field deflection induced by the driving field distribution in EIT, and showed that even a broadband pulse can be deflected without serious spreading. In the fast light area, we examined the effects of noise and parameter deviations in a bichromatic Raman type white light cavity. Taking advantage of the adjustable absorption of EIT, we showed that EIT in a laser cavity can have either first-order or second-order phase transitions. Last but not least, we show that the adiabatic population transfer can be used to reverse the weak measurement of an arbitrary field with finite photon number.
96

Ethanol-induced liver injury preventing apoptosis /

Cohen, Jessica I. January 2010 (has links)
Thesis (Ph. D.)--Case Western Reserve University, 2010. / [School of Medicine] Department of Nutrition. Includes bibliographical references.
97

The use of warmed intravenous fluid in reducing hypothermia in patients after major surgery

Kwok, Ka-wai., 郭嘉慧. January 2010 (has links)
published_or_final_version / Nursing Studies / Master / Master of Nursing
98

Effect of earplug use and factors associated with noise induced hearing loss among occupational workers in Guangzhou, China

Huang, Yuzhang, 黄羽张 January 2012 (has links)
Background: Noise is one of the most important forms of environmental pollution among developed and developing countries. A report from UK National Study of Hearing estimated that around 440 million people suffer from noise induced hearing loss in EU countries with 1–1.6 million disability-adjusted life year lost. In China, the Second China National Sample Survey on disability in 2007 revealed that about 27.8 million people suffered from hearing impairment, and 73.4% of which (about 20 million) were diagnosed with disability. The prevalence of hearing impairment was estimated to be 2.1% in the general population, and increased to 11.0% among those aged greater than 65 years. Objective: To find out the effect of earplug on noise induced hearing loss (NIHL), as well as understanding the source and exposure of noise in the industry, to estimate the prevalence of NIHL in factories with noise exposure, to analyze relationships between NIHL and age, sex, dose and duration of occupational noise exposure, type of work, use of hearing protection products, education level and other factors. Significant risk factors identified were used to provide evidence-based recommendations in prevention and control of NIHL. Study Design: Retrospective, cross-sectional study Method: A total of 1874 workers exposed to noise in a compressor factory in Guangzhou, China were included. Between September 2011 and January 2012, physical examination including a screening program of hearing loss, pure tone audiometry test were carried out among workers including information on age, sex, work types, noise exposure level, exposure time, as well as the questionnaire about earplug using status, status of using ear products report by company, smoking status, education level, discharge of ear, history of herpes zoster, history of using ototoxic drugs, history of ear surgery, family history of NIHL, systolic blood pressure, diastolic blood pressure. The outcome variable is the audiometric mean value which reflects hearing status of the subjects. Subgroup differences in mean value of audiometry were compared by independent sample t-test. Multiple linear regression and logistic regression models were used to evaluate associations between earplug use and NIHL, adjusted for other potential confounders. Factors associated with earplug use were also identified. Result: 1873 workers took part in the study (both physical examination and questionnaire) The prevalence of NIHL is 381 (20.3%) from study, and an average noise level of 83.5 dB was detected in the factory across different types of working place. The pure tone audiometric mean value (PTA) is 26.7 dB with a standard deviation of 4.8. The mean PTA value for those using earplug is 25.81 dB, which was significantly lower than those not using earplug with a mean PTA value of 1.54 dB (p < 0.001). A 0.962 mean difference is detected between noncontinuous earplug usage group and continuous usage group. Multiple linear regression model showed a dose response effect in use of earplug on NIHL, with an estimated mean PTA 1.49 dB (p-value <0.001) and 0.96 dB (p-value = 0.001) lower than those not using earplug at all. Hearing protective effect with part of dose response relationship is found in education level groups as well. Workers from technical school have a 5.974 dB lower of mean PTA, where the decrease is 3.909 dB in high school group, reference of primary level. Moreover, ever smokers show 1.557 dB higher on reference as nonsmoker. Other significant results can be found in family history of NIHL, ototoxic drug using, with statistical significant, respectively, with the direction of positive to NIHL, which shows harmful effect on workers’ hearing. Multivariable logistic regression model is used to find out factors associated with earplug usage. In the model, higher education level is found to be associated with higher earplug usage, especially among participants from technical schools, with an adjusted odds ratio (AOR) of 34.07, whereas those from high school group have an AOR of 12.35.(With Primary school group being the reference group.) Workers whose daily tasks involve phosphorus board, punching press, compressor are found to have a relatively low percentage on earplug usage compliance, with AOR of 0.55, 0.41, 0.23 respectively. (Those from machine shops are used as the reference group.) The result is in accordance with their positive correlation on NIHL. Conclusion: Use of earplug was found to be protective to NIHL. Factors such as education level, smoking status, discharge of ear, family history of NIHL and certain types of work were found to be associated with lower risk of NIHL. To protect hearing of the workers and reduce NIHL prevalence, provision of and education on hearing protection products and supervision of continuous use of earplug in noise exposed industry should be implemented. Occupational health monitoring to the enterprises should be enhanced by health sectors of Chinese government. Due to the limitation of retrospective design of this dissertation, further cohort studies are called for to provide stronger evidence of factors’ effect on NIHL. / published_or_final_version / Public Health / Master / Master of Public Health
99

The Influences of Stress and Structure on Mining-induced seismicity in Creighton Mine, Sudbury, Canada

SNELLING, PAIGE 15 September 2009 (has links)
The Creighton Mine is a structurally complex and seismically active mining environment. Microseismic activity occurs daily and increases with depth, complicating downward mine expansion. Larger magnitude events occur less frequently but can damage mine infrastructure, interrupt operations and threaten worker safety. This thesis explores the relationships between geological structure and mining-induced seismicity through geological, seismological and numerical modelling investigations in an area known as the Creighton Deep, with concentration on the 7400 Level (2255 m). Geological features within the Creighton Deep have a reported association with seismic activity. Four families of shear zones were identified during field investigations, the most prominent striking SW and steeply dipping NW. Seismicity from 2006-2007 is analyzed. Spatial and temporal trends and seismic event parameters show little correlation to shear zone geometry. Instead, seismic event parameters correlate to spatial clusters of events. A remote cluster of events to the southwest of the excavation exhibits anomalously high seismic parameter values. This area of the mine continues to be a source of elevated seismicity. Fault plane solutions are utilized to compare shear zone geometry with active slip surfaces. Solutions for macroseismic events are inconsistent, while microseismic event focal mechanisms have similar pressure, tension and null axes. The resulting solutions do not align with shear-zone orientations. A stress inversion using microseismic focal mechanism information yields a stress tensor that is comparable to the regional stress tensor. Universal Distinct Element Code numerical models demonstrate that a yield zone exists immediately surrounding the excavation. SW-striking shear zones modify the stress field, resulting in increased stress to the southeast of the excavation. These high-stress zones are areas of preferred seismic activity. Slip is induced on select SW-striking shear zones to the south of the excavation as well as localized yielding. The characteristics of mining-induced seismicity do not correlate to shear zones. Seismicity does compare to modelled stress: the yielded rock mass adjacent to the excavation has little seismicity; areas of high stress are areas of rock mass damage and dense seismic activity. It is thus proposed that seismicity in the Creighton Deep results from stress-induced rock mass degradation rather than fault-slip. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2009-09-11 10:35:17.525
100

Pregnancy interruption using mifepristone (RU486) a new choice for women : [a report sumitted [sic] in partial fullfillment [sic] of a Master of Science [degree in] (Parent-Child Nursing)] /

Mackenzie, Susan J. Yeo, Seonae. January 1996 (has links)
Thesis (M.S.)--University of Michigan, 1996.

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