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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.
281

影響證交所跨國上市比率因素之探討:門檻模型之應用 / A discussion on contributors of cross-listing ratio of stock exchanges: An application of panel threshold model.

陳貫宇, Chen, Kuan-Yu Unknown Date (has links)
本研究之模型乃採用Hansen於1999年提出之Panel Threshold Model,並針對全球23個不同國家中之23間證交所於1995~2006年間的資料,探討各類影響企業選擇跨國上市之因素,是否會因模型的門檻變數─經濟成長率的變動而對被解釋變數─跨國上市率出現結構改變的影響。實證的結果發現:各變數中唯有市場集中度此一變數具顯著的門檻效果,且在其兩個門檻值的分類中都和跨國上市率呈顯著正相關;這樣的結果除了符合Heiko (2001) 的研究之外,更近一步的我們還發現低於門檻值部分的樣本其對跨國上市率的影響大於高於門檻值部分的樣本。此外,本文的實證結果也指出:對跨國上市率有顯著正相關的因素分別為:本益比、通貨膨脹率及經濟成長率。而對跨國上市率有顯著負相關的因素則為:週轉率、利率和新上市籌資率。 / This paper adopts the Panel Threshold Model suggested by Hansen in 1999 as our main idea to make a study of contributors of cross-listing ratio of stock exchanges. In order to find out whether the explanatory variables will make cross-listing ratio occur structure change, we use GDP growth rate as our threshold variable and take 23 stock exchanges of 23 different countries as research samples. The results are as follows, we found that the only one variable that has threshold effect is the degree of market concentration, and in both regimes it has positive relations to the cross-listing ratio. The result not only supports the research of Heiko (2001), but also points out that the higher regime part has more powerful influence to the cross-listing ratio than the lower regime part. Besides, we still found that variables have positive relations to the cross-listing ratio are PE ratio, inflation rate and GDP growth rate. Furthermore, variables like turnover ratio, interest and capital raised by new shares ratio have negative relations to the cross-listing.
282

Effects of Magnesium on Temporary Threshold Shift

Casey, Sarah 01 July 2003 (has links)
Previous literature has demonstrated that supplemental magnesium may have a prophylactic effect on noise induced hearing loss (NIHL). The purpose of this study was to replicate the findings of a previous investigation concerning the beneficial effects of supplemental magnesium on TTS in humans. Forty participants with normal hearing were divided into two groups, experimental and control. The experimental group received a single, 150 mg dose of supplemental magnesium and the control group received a placebo. After an hour in a quiet environment, all participants were exposed to a narrowband noise centered at 2000 Hz and presented at 105 dB SPL. Audiometric thresholds were measured for the frequency range 250 Hz - 8000 Hz prior to the noise exposure, and then immediately, 30 minutes, and 60 minutes post-noise exposure. Both groups experienced TTS at and above 2000 Hz. The largest TTS was observed immediately following the noise exposure in both groups. There was no significant difference in TTS between the experimental group and the control group. It was concluded that a single dose of 150 mg of supplemental magnesium was not effective in reducing or preventing TTS.
283

Preventing Vocal Fold Dehydration Using Aerosolized Salinein an Excised Porcine Model

Hansen, Mallory Lynn 01 December 2016 (has links)
Vocal fold hydration is important for efficient oscillation during voice production. Dehydration of the vocal fold surface is believed to produce adverse effects on the voice. Specifically, low environmental humidity, mouth breathing, and certain medical conditions may contribute to laryngeal and vocal fold dehydration. This dehydration effect may be quantified using the observed pressure and flow at the onset of phonation, operationally defined as phonation threshold pressure (PTP) and phonation threshold flow (PTF), respectively. Previous research has documented that nebulized isotonic saline (0.9% Na+Cl-) can reduce PTP. Additionally, the topical application of liquid saline increases vocal fold hydration in excised larynx studies. However, no studies have examined the prevention of vocal fold dehydration using aerosolized saline in an excised larynx mechanical model. The purpose of the current investigation was to determine the preventive effects of aerosolized isotonic saline in a physiologically realistic excised larynx model. Using a prospective, mixed experimental design with a control group, five bench-mounted, excised porcine larynges received 4-min doses of aerosolized saline delivered supraglottally for a total of 24 min. Subsequently, larynges received 1-min doses of desiccated air (<1% relative humidity) delivered supraglottally. A control group of five porcine larynges received only desiccated air. Phonation was attempted following each dose of aerosolized saline or desiccated air. The desiccation doses were repeated for both groups until the larynges were no longer able to phonate. The PTP and PTF were measured at baseline and following each dose of aerosolized saline or desiccated air. Analysis of the results indicated that aerosolized saline significantly delayed the adverse effects of vocal fold dehydration based on the total number of desiccation doses required to cease phonation for experimental versus control groups (p = .002). Trends demonstrated that PTP decreased after aerosolized saline and increased during desiccation trials. The PTF trends were similar during desiccation. The results from this study indicate that aerosolized saline may be used prophylactically to prevent vocal fold dehydration. These findings offer important advances in vocal fold hydration theory and dehydration prevention in a physiologically realistic excised mechanical model.
284

A Comparative Study For Nonlinear Structure Of The Interest Rate Pass-through

Deger, Osman 01 September 2012 (has links) (PDF)
This study investigates the interest rate pass through from the money market rate to the lending rate by utilizing monthly data of fifteen countries, grouped as high income, upper middle income and lower middle income, over the period 1999:01-2011:09. Taking the linear cointegration test of Engle-Granger as benchmark, we employ threshold cointegration tests of Enders and Siklos (2001) in order to account for the possible nonlinearities in the pass-through process. Empirical results reveal that the pass through process is complete in three countries / Republic of Korea, Latvia and Malaysia and the adjustment of the lending rate is symmetric in two countries / Armenia and Republic of Korea. Moreover, it is observed that the adjustment of the lending rate is upward sticky in six countries / Bolivia, Philippines, Malaysia, Dominican Republic, Thailand and Croatia, whereas it is downward sticky in seven countries / Ukraine, Sri Lanka, Latvia, Peru, Kuwait, Hong Kong and Czech Republic. Furthermore, our estimation results suggest that heterogeneities in the pass-through mechanism across countries can be mainly explained by income level, inflation, market power, financial sector development and market volatility.
285

Effekter av habitatstorlek, konnektivitet och områdesskydd på förekomst av revlummer Lycopodium annotinum och mattlummer Lycopodium clavatum i Södermanland

Båverman, Evelina January 2015 (has links)
Studien syftar till att testa teorier om effekter av habitatstorlek, konnektivitet, områdesskydd, habitatmängd och fragmentering på enskilda arters förekomstmönster, samt undersöka existensen av fragmenteringströskel och utdöendetröskel. Förekomstdata för revlummer Lycopodium annotinum och mattlummer Lycopodium clavatum har insamlats i 61 skogsfragment utspridda i 10 kartrutor à 2,5×2,5 km i landskapet Södermanland. I vardera skogsfragment undersöktes en yta om 500m2. Revlummer förekom i 13 och mattlummer i 10 av de undersökta skogsfragmenten. I 7 kartrutor förekom revlummer i minst 1 skogsfragment, för mattlummer var motsvarande siffra 8 kartrutor. Resultaten visar att habitatstorlek har en signifikant positiv effekt på förekomst av revlummer och mattlummer samt att konnektivitet har en signifikant positiv effekt på förekomst av mattlummer. Områdesskydd, habitatmängd och fragmentering i landskapet har ingen påvisad effekt på förekomst av dessa arter och ingen fragmenteringströskel eller utdöendetröskel har hittats. Dessa resultat indikerar att ett bevarande av skogsfragment med stor storlek och hög konnektivitet är viktigt för de undersökta arternas fortsatta livskraft. / The aim of this study is to test theories of the effects of habitat size, connectivity, area protection, habitat amount and fragmentation on the occurrence of single species, plus examining the existence of a fragmentation threshold and an extinction threshold. Occurrence of stiff clubmoss Lycopodium annotinum and stag’s-horn clubmoss Lycopodium clavatum was examined in 61 forest fragments scattered over 10 large 2,5×2,5 km plots, located in the county of Stockholm in Sweden. In each forest an area covering 500m2 was searched for the two species. Lycopodium annotinum occured in 13 and L. clavatum in 10 of the investigated fragments. Lycopodium annotinum occurred in at least 1 fragment in 7 large plots, 8 large plots was the corresponding number for L. clavatum. The results showed a significant positive effect of habitat size on the occurrence of both species and a significant positive effect of connectivity on the occurrence of Lycopodium clavatum. Area protection, habitat amount and fragmentation had no observed effect on the occurrence of these species, and no fragmentation threshold or extinction threshold was found. These results indicate the importance of preserving large forest fragments with high connectivity, to assure continued viability of the examined species.
286

The effects of threshold nonlinearities on the transformation of rainfall to runoff to floods in a lake dominated catchment system

Kusumastuti, Dyah Indriana January 2007 (has links)
[Truncated abstract] Runoff generation behaviour and flooding in a lake dominated catchment are nonlinear, threshold-driven processes that result from the interactions between climate and various catchment characteristics. A complicating feature of the rainfall to runoff transformation, which may have implications for the flood frequency, is that the various surface and subsurface flow pathways are dynamic, heterogeneous and highly nonlinear, consisting of distinct thresholds. To understand the impact of threshold nonlinearities on the rainfall-runoff transformation in such catchments, a systematic examination was carried out to investigate runoff generation behaviour of the catchment itself, the overflow behaviour of a lake in combination with the catchment draining into it, as well as the lake organisation within a lake chain network. Three storage based thresholds were considered: the catchment field capacity storage governing catchment subsurface stormflow, total storage capacity governing catchment surface runoff, and lake storage capacity governing lake-overflow. ... Through these investigations, this thesis has provided valuable insights into the process controls of lake-overflow events and the associated flood frequency behaviour in lake dominated catchments. In particular, the relative roles of climate, soil depth, the soil?s drainage capacity, as well as the relative geometry of the lake vis a vis the contributing catchment, in the determination of the dynamic characteristics of lake-overflow events and associated flood frequency behaviour have been highlighted. In addition, the importance of lake organization, as expressed in terms of the average ratio of catchment area to lake area and the spatial variability of this ratio from upstream to downstream, and their impact upon connectivity and flood frequency have also been explored. The outcomes of this study highlight the importance of thresholds governing flood frequency, and provide insights into the complex interactions between rainfall variability and the various threshold nonlinearities in the rainfall-runoff process, which are shown to have a significant impact on the resulting flood frequency curves. The improved understanding of these process controls will be useful in assisting the 1 management of the catchment-lake system in the study region, and in regions elsewhere. In particular, the outcome of this study can provide guidance towards the adoption of various management strategies for lake chain systems by illustrating the effects of potential flow interruption and retardation as ways to assist in flood prevention and mitigation, whether it is aimed at decreasing the frequency of occurrence of lake overflows, or merely decreasing the flow magnitude for a given return period.
287

Avalia??o gen?tica da probabilidade de prenhez em novilhas da ra?a Sindi via modelos de limiar em regress?o aleat?ria

Oliveira, Lorena Tavares de 19 August 2016 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-03-07T17:37:49Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lorena_tavares_oliveira.pdf: 1039032 bytes, checksum: 99b6c1aac4a55a13ac7523067c7e14af (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-03-30T14:58:02Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lorena_tavares_oliveira.pdf: 1039032 bytes, checksum: 99b6c1aac4a55a13ac7523067c7e14af (MD5) / Made available in DSpace on 2017-03-30T14:58:02Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) lorena_tavares_oliveira.pdf: 1039032 bytes, checksum: 99b6c1aac4a55a13ac7523067c7e14af (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Objetivou-se com este estudo estimar par?metros gen?ticos e fenot?picos para probabilidade de prenhez nas idades 15, 19, 23, 27, 31, 35, 39 e 43 meses (PP_15, PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 e PP_43), em novilhas da ra?a Sindi, via modelo de limiar em regress?o aleat?ria utilizando os polin?mios ortogonais de Legendre de segunda, terceira e quarta ordem, considerando a homogeneidade e heterogeneidade de vari?ncia residual. Os componentes de covari?ncia foram estimados por abordagem Bayesiana, utilizando o programa THRGIBBS3F90. Foram inclu?dos os efeitos fixos de criador, fazenda do criador, ano de nascimento, esta??o de nascimento e como covari?vel (de efeito linear) foi considerado o peso da vaca na idade em que ela concebeu. Al?m desses efeitos para todas as idades estudadas, foram considerados os efeitos aleat?rios gen?ticos aditivos, de ambiente permanente e residual. O melhor modelo para a an?lise RRTM foi o LEG_4441 que obteve as seguintes estimativas de herdabilidade 0,34; 0,41; 0,45; 0,41; 0,37; 0,32; 0,32; 0,33 para PP_15, PP_19, PP_23, PP_27, PP_31, PP_35, PP_39, PP_43, respectivamente. As estimativas das correla??es gen?ticas obtidas entre PP_15 com PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 e PP_43 foram 0,1; -0,39; -0,65; -0,83; -0,93; -0,81; -0,71, respectivamente. As estimativas das correla??es fenot?picas para PP_15 com PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 e PP_43 foram respectivamente 0,12; -0,09; -0,17; -0,22; -0,26; -0,25; 0,40. A an?lise que utilizou modelo LEG_4441 foi a mais indicada para estimar os par?metros gen?ticos para a probabilidade de prenhez em diferentes idades em novilhas da ra?a Sindi, indicando que a prenhez precoce possui variabilidade gen?tica para ser inclu?da como caracter?stica alvo de sele??o em programas de melhoramento, com potencial para se obter ganhos gen?ticos satisfat?rios. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / Our aim with this study was estimating genetic and phenotypic parameters for pregnancy probability at 15, 19, 23, 27, 31, 35, 39 and 43 month old (PP_15, PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 and PP_43) in Sindhi heifers, by using threshold model in a random regression framework, adopting Legendre orthogonal polynomials of second, third and fourth order, considering homogeneity and heterogeneity of residual variance. Covariance components were estimated by Bayesian approach using THRGIBBS3F90 program. The model included the fixed effects of herd, herd of the farm, year of birth, birth season and as a covariate (with linear effect) was considered the weight of the cow at the age when she calved. In addition to these effects for all ages studied, additive genetic, permanent environmental and residual random effects were considered. The best model for the analysis was the RRTM LEG_4441 which obtained the following heritability estimates: 0.34; 0.41; 0.45; 0.41; 0.37; 0.32; 0.32; 0.33 to PP_15, PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 and PP_43, respectively. Genetic correlation estimates between PP_15 with PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 and PP_43 were 0.1; -0.39; -0.65; -0.83; -0.93; -0.81; -0.71, respectively. Phenotypic correlation estimates for PP_15 with PP_19, PP_23, PP_27, PP_31, PP_35, PP_39 and PP_43 were respectively 0.12; -0.09; -0.17; -0.22; -0.26; -0.25; 0.40. The analysis by using LEG_4441 model was the most appropriate to estimate genetic parameters for pregnancy probability at different ages in Sindhi heifers, indicating that early pregnancy has genetic variability to be included as a goal trait selection in breeding programs, with the potential to achieve satisfactory genetic gains.
288

Uma anÃlise do processo de convergÃncia dos municÃpios brasileiros no perÃodo de 1980 A 2000. / An analysis of the convergence process of the Brazilian municipalities from 1980 to 2000.

Herson Lee Carvalho 29 April 2010 (has links)
nÃo hà / O papel das condiÃÃes iniciais sobre a determinaÃÃo dos nÃveis de renda de longo prazo das economias e, consequentemente, sobre a desigualdade à um tema que ainda permanece em ativo debate. O objetivo do trabalho à realizar uma anÃlise empÃrica, atravÃs do modelo threshold, do processo de convergÃncia de renda entre os municÃpios brasileiros no perÃodo de 1980 a 2000, com o intuito de verificar a existÃncia de clubes de convergÃncia. De maneira geral, o capital humano mostra-se estatisticamente significante para explicar o processo de crescimento econÃmico de todos os grupos de municÃpios. Com relaÃÃo ao capital fÃsico, este se mostrou significantemente negativo, o que demonstra um papel negativo para o investimento pÃblico realizado nos municÃpios brasileiros. / The role of initial conditions on the determination of levels of long-term income economies and, consequently, on the inequality is a theme that still remains in active debate. The goal of the work is to perform an empirical analysis, model threshold, the process of convergence of income between the Brazilian municipalities in the period from 1980 to 2000, in order to verify the existence of clubs of convergence. Generally speaking, human capital is statistically significant to explain the process of economic growth for all groups of municipalities. With respect to physical capital, this proved significantly negative, which shows a negative role for public investment in Brazilian municipalities.
289

Using distortion product otoacoustic emissions to investigate the efficacy of personal hearing protection

Newland-Nell, Annette Caroline 03 March 2004 (has links)
This study aimed to investigate the effectiveness of the Quiet earplug noise protectors worn by a group of South African industrial workers exposed to excessive noise in the workplace. This was achieved by investigating the prevalence and amplitudes of distortion product otoacoustic emissions (DPOAEs), as they have been found to be sensitive to the effects of noise on the cochlea (Vinck, Van Cauwenberge, Leroy,&Corthals, 1999, p. 52). DPOAEs were recorded before and after noise exposure and were compared in order to determine whether the earplugs are providing sufficient protection against cochlear damage. DPOAEs were recorded using a test protocol where the primaries are fixed at L1 = 60dB SPL and L2 = 35dB SPL (L1 - L2 = 25dB) with an f2/f1 ratio of 1.18. The f2 frequencies were selected to correspond closely to the audiometric test frequencies of 2000Hz, 3000Hz, 4000Hz, 6000Hz and 8000Hz. The study found the prevalence of DPOAEs to be statistically stable and repeatable. This was true for DPOAEs measured successively during the same test sitting, as well as comparing prevalence determined before and after exposure to eight hours of noise. DPOAE prevalence alone was therefore not found to be a good indication of the temporary threshold shift (TTS) associated with the effects of noise on the cochlea. However, a significant finding of the study was that normal DPOAEs were recorded in only six right ears (24%) and seven left ears (28%) before noise exposure, even though all the subjects presented with hearing thresholds better than 25dB SPL. This may mean that cochlear pathology is already evident in some of the subjects tested. Further results of the study showed DPOAE amplitudes to be sensitive to the negative effects of excessive noise, as there was a significant difference between DPOAE amplitudes measured before and after the noise exposure. DPOAE amplitudes, specifically in the frequencies that are known to be affected by noise such as 4000Hz and 6000Hz, measured after the work-shift were significantly smaller than those measured before exposure to noise. Although correct usage of the earplugs could not be controlled for the duration of the noise exposure, each subject was instructed on the correct usage of the hearing protection before entering the noise zone. Bearing this limitation of the study in mind, because DPOAE amplitudes were reduced the implication is that the Quiet earplugs are not providing sufficient protection against the harmful effects of noise. / Dissertation (M (Communication Pathology))--University of Pretoria, 2005. / Speech-Language Pathology and Audiology / Unrestricted
290

Alterations in human visceral sensation induced by non-invasive cortical and lumbosacral magnetic stimulation in health and disease

Algladi, Tarig January 2012 (has links)
Background: Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder (FGID) which can be defined as chronic, relapsing visceral pain with bloating associated with change in bowel habit. It affects up to 10-15% of the adult population in the UK and is more common in females. The cost of IBS in terms of health care utilisation is substantial, exceeding £45.6 million per year in the UK alone, yet its pathophysiology is incompletely understood. Visceral pain is the main and most difficult symptom to manage in IBS and many IBS female sufferers compare it to labour pain in its severity. Modulating visceral pain in healthy volunteers and IBS patients is therefore an important research area. Non-invasive magnetic stimulation may play a crucial role in this respect. Aim:The aim of this study is to ascertain whether non-invasive repetitive magnetic stimulation applied to the motor cortex and/or lumbosacrum can modulate gastrointestinal pain originating from the anorectum. Methods:Participants: 16 healthy volunteers and 10 IBS patients aged 18 and above were included in the study.Questionnaires: Healthy volunteers and IBS patients were asked to complete anxiety and depression questionnaire and IBS patients were requested to fill in an IBS severity questionnaire.Motor measurements in healthy subjects: Single-pulse lumbosacral magnetic stimulation (LSMS) was applied to the lumbosacral area for the anal sphincter where the largest motor evoked potential (MEP) amplitude response was detected. Single-pulse transcranial magnetic stimulation (TMS) was then performed at the pre-determined resting motor thresholds (RMT) for the anal sphincter and the hand.Sensory measurements in healthy subjects and IBS patients: Electrical stimulation was used to assess the changes in sensory and pain thresholds in the anorectal area. The subjects were asked to score the pain intensity using five-point categorical rating scales. In addition they were asked to describe the pain experienced using a shortened form of the McGill Pain Questionnaire. Intervention: Healthy volunteers received 6 paradigms of magnetic stimulation in a randomised order i.e. 3 repetitive LSMSs (1 Hz, 10 Hz and sham) and 3 repetitive TMSs (1 Hz, 10 Hz and sham) to investigate their modulatory effects on visceral sensitivity and to determine which of these interventions is most effective. The most effective active interventions (1 Hz rLSMS and 10 Hz rTMS) together with one sham were then trialled in a randomised fashion on IBS patients.Post intervention: Motor excitabilities were repeated at 30 min after each intervention. The assessment of sensory and pain thresholds at anal sphincter and rectum were done immediately, 30 and 60 min after each intervention. Results:Application of 1 Hz rLSMS led to alterations of anal sphincter motor excitabilities and resulted in a significant increase in the amplitude of lumbosacal-anal motor evoked potentials (MEPs) in healthy volunteers recorded at 30 min post intervention. In healthy volunteers, 1 Hz rLSMS and 10 Hz rTMS caused a significant increase in the rectal pain thresholds experienced immediately, 30 and 60 min after each intervention. 10 Hz rLSMS and 1 Hz rTMS only led to a significant rise in rectal pain thresholds immediately after their application. Furthermore, there was a significant increase in the rectal pain thresholds immediately, 30 and 60 min following 1 Hz rLSMS and 10 Hz rTMS in IBS patients. Conclusion:The application of magnetic stimulation to the cortical and lumbosacral areas to modulate visceral pain is a new concept, which reduced rectal sensitivity to painful stimuli and offers a much needed new approach in the management of abdominal pain in patients with IBS.

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