• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 253
  • 152
  • 69
  • 33
  • 29
  • 14
  • 8
  • 6
  • 4
  • 4
  • 3
  • 2
  • 2
  • 2
  • 2
  • Tagged with
  • 660
  • 54
  • 53
  • 53
  • 41
  • 40
  • 40
  • 39
  • 39
  • 38
  • 35
  • 34
  • 32
  • 32
  • 28
  • 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.
21

Psychological morbidity after miscarriage. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Chapter 2 evaluates the effectiveness of two simple and widely applied self-report psychometric questionnaires: the 12-item General Health Questionnaire (GHQ-12) and Beck Depression Inventory (BDI) in detecting psychological morbidity after miscarriage. Both GHQ-12 and BDI demonstrated satisfactory psychometric properties and both questionnaires were found to be effective in detecting general psychiatric disorders and depression respectively. / Chapter 3 reports the application of GHQ-12 and BDI in assessing the psychological well-being of 280 miscarrying women over a one-year longitudinal course after the loss. The psychometric outcomes were also compared with a community cohort unexposed to pregnancy loss. The study confirmed that although psychological distress reduces over time, the psychological impact following miscarriage is significant and could be enduring. Patients who were more distressed immediately after miscarriage continued to be at a higher risk of psychological morbidity at a later stage. / Chapter 4 assesses the possible underlying risk factors associated with psychological morbidity following miscarriage over a one-year longitudinal course. It has demonstrated that while a poor marital dyad and psychological distress experienced immediately after miscarriage are consistent predisposing factors, some obstetric variables such as the type of medical management, a history of abortion and prior ultrasound evidence of fetal viability contribute to the development of psychological morbidity at various time points along its evolutionary course. / Chapter 5 reports a randomised controlled trial involving 280 miscarrying women in assessing the effectiveness of a psychological counselling programme in reduction of psychological morbidity. A 30% reduction in the proportion of patients with psychological morbidity was found three months after miscarriage in the counselling group, suggesting a potential clinical beneficial effect, albeit not statistically significant. This potential effect was more profound for selected patients who were initially more distressed after miscarriage. / Chapter 6 reports our exploratory findings of the psychological reaction of 83 male partners after miscarriage and it reports the gender differences over a one-year longitudinal course. A significant proportion of men were found to report psychological distress and depressive symptoms immediately after miscarriage. When compared with their female partners, the psychological impact was less intense and less enduring. / Chapter 7 concludes the thesis and proposes directions for future research. / Miscarriage (spontaneous abortion) is the most common complication of pregnancy with 15-20% of clinically recognised pregnancies aborting spontaneously. It is also one of the commonest gynaecological conditions leading to hospitalisation, accounting for more than 10% of gynaecological admissions in Hong Kong. The common occurrence and the procedural simplicity involved in the medical management, however, may tend to obscure its psychological impact. While emerging evidence has suggested that miscarriage could be associated with significant and possibly enduring psychological consequences, many questions remain unanswered, such as how to detect and screen for psychological morbidity after miscarriage; how long the symptoms last or when do they resolve; what are the underlying risk factors throughout its longitudinal course; what is the psychological impact on the male partner; and whether psychological intervention is helpful. In addition, nearly all studies have been conducted in Caucasian societies with the effect on other ethnic groups remaining largely unexplored. / This thesis specifically addresses the following aspects in assessing and managing psychological morbidity following miscarriage: Chapter 1 firstly introduces the clinical aspects of miscarriage, including the definition, incidence, risk factors, clinical manifestations and the current management options. It then discusses the current evidence available on the psychological aspects of miscarriage and outlines the deficiency in current knowledge. Finally, the hypotheses for this thesis are proposed. / Lok Hung Ingrid. / "May 2006." / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1567. / Thesis (M.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 248-276). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / School code: 1307.
22

Development and 6-month validation of a typology of Chinese women experiencing miscarriage based on pregnancy, peraonality and cultural factors. / CUHK electronic theses & dissertations collection

January 2007 (has links)
In the first phase of this study, the cluster analysis results of 208 WEM provided initial empirical support for this typology. Three subtypes of WEM were identified. They were "Adjusted Women" (AW, N = 54, 26%), "Dysphoric/Mixed Type Women" (DW, N = 57, 27%), and "Gender-Bound Women" (GW, N = 97, 47%). Partially supporting the hypothesis, GW experienced the worst adjustment as reflected in their high level of perinatal grief symptoms compared to AW and DW. Further examination of the demographic characteristics of each WEM subtype showed that while DW reported relatively stronger personality (i.e., trait anxiety, trait depression, and neurotic personality) and cultural vulnerabilities (i.e., traditional ideal personhood and self-sacrifice) compared to AW, GW's reports of personality and cultural vulnerabilities faked the worst among the 3 WEM subtypes. Cluster-constrained hierarchical regression analyses revealed a distinct set of predictors for immediate postloss adjustment of AW, DW, and GW. Instead of a complete nested model, the present data fitted a partially nested model where AW were nested within GW, and DW represented a mixed type of WEM. Specifically, AW's perinatal grief was affected by pregnancy factors whereas GW's was affected by pregnancy, personality, and cultural factors. DW's perinatal grief was not affected by pregnancy factors but by personality and cultural factors. / In the fourth phase of this study, pregnancy, personality, and cultural factors as well as spousal emotional social support were reexamined for their possible implications for WEM's and the pregnant controls' psychological distress, state anxiety symptoms, and state depressive symptoms at 6 months following the initial assessment. The results showed that spousal emotional support at a 6-month follow up was a salient predictor of psychological distress state anxiety symptoms, and state depressive symptoms at 6 months after the initial assessment for both WEM and the pregnant controls While spousal emotional support at the initial assessment did not have the same effect, this result suggested that to mitigate the longer term poor psychological adjustment of WEM and pregnant women, sustained spousal emotional support is needed. Trait anxiety at the initial assessment was also a strong predictor of WEM's psychological distress, state anxiety symptoms, and state depressive symptoms at 6 months post miscarriage. Pregnancy factors at the initial assessment were only moderately related to the psychological adjustment of WEM and the pregnant controls, and cultural factors at the initial assessment were not related to any of the adjustment indicators at the 6-month follow up. (Abstract shortened by UMI.) / In the second phase of this study, comparisons were made between the 3 WEM subtypes and women with healthy uncomplicated pregnancy (pregnant controls, N = 258). The results showed that the 3 WEM subtypes experienced varying levels of adjustment problems---that is, psychological distress, state anxiety symptoms, and depressive symptoms---compared to the pregnant controls. GW, in particular, were 8 times more likely to be classified as psychological distress caseness and 4 times more likely to be classified as state anxiety caseness and state depression caseness, even after controlling for pregnancy factors and spousal emotional social support. / In the third phase of this study, the author attempted to establish predictive validity of the proposed WEM typology using 6-month 2-wave longitudinal data A subsample from Phase One and Phase Two of this study, including 103 WEM (AW = 33, 32%; DW = 27, 26%; GW = 43, 42%) and 139 pregnant controls, provided information on their psychological distress, state anxiety symptoms and depressive symptoms, as well as on their motivation to reproduce at 6 months after the initial interview. Although GW were significantly more likely than AW and DW to report being pregnant or having the intention to conceive at 6 months post miscarriage, no significant differences were observed between the 3 WEM subtypes in their psychological distress, state anxiety symptoms, and state depressive symptoms. / The present 4-phase study was an attempt to propose an integrated conceptual model to advance understanding of Chinese women's adjustment to miscarriage; that is the perinatal grief symptoms, psychological distress, state anxiety symptoms, and depressive symptoms they experience in response to miscarriage. Through a comprehensive review of sociobiological theory, attachment theory, psychoanalytic theory and the feminist perspective, the author proposes a conceptual model involving 3 major pathways, namely pregnancy, cultural, and personality factors. It was hypothesized that 3 subtypes of women who experienced miscarriage (WEM) (Adjusted Women, AW; Dysphoric Women, DW; Gender Bound Women, GW) could be identified with each subtype being affected by a combination of different factors. Specifically, it was hypothesized that AW would be affected by pregnancy factors, DW by pregnancy and personality factors, and GW by pregnancy, personality, and cultural factors. / Yan Chau Wai Elsie. / "June 2007." / Adviser: Catherine So-Kum Tang. / Source: Dissertation Abstracts International, Volume: 69-01, Section: B, page: 0705. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 104-120). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.
23

Factors governing spontaneous ignition of combustible dusts

Joshi, Kulbhushan Arvind 09 April 2012 (has links)
The problem of self-heating of combustible dusts accumulated on hot surfaces has caused several fires and dust explosions. The current test standards (ASTM E 2021, EN50281-2-1) used to ensure safe environment for a given dust, define a safe temperature of the flat hot surface for certain dust layer thickness. Since in these standards, measurement of temperature is taken along the centerline, they mainly represent a simplified scenario of one-dimensional heat transfer. A need to investigate behavior of spontaneous ignition in dust deposits in complex geometries forms the motivation of this work. The effect of hot surface geometry is experimentally studied by devising wedge-shaped configurations having angles of 60o and 90o. Results show that ignition always occurred around the top region in the case of 60o wedge, and in the top and middle regions in the case of 90o wedge. These trends are explained by investigating three parameters affecting the ignition behavior, namely, the heat transfer from the hot plate to the dust, the rate of heat transfer between different regions within the dust and the minimum volume of dust required to produce sufficient heat release. A mathematical method has been proposed to predict the ignition behavior of dust deposit subjected to any boundary conditions arising due to geometrical confinement. Further, numerical simulations have been carried out to simulate the conjugate heat transfer in the interface of dust surface and air. Both analyses, mathematical and numerical, compare well with the experimental data. Furthermore, in the standard test method, ASTM E- 2021, a metal ring is used to contain the sample dusts. It is observed from experimental and numerical simulations that the resultant temperature field is not one-dimensional as desired since the corner part ignites first due to heat transfer from both the bottom plate and the metal ring, which is at almost same temperature as that of bottom plate. Theories those describe the thermal ignition in these standard tests, use the assumption that the heat flow is unidirectional. Therefore, a better substitute to the metal ring has been proposed as a ring made out of an insulating material (having low thermal conductivity). This makes the heat transfer to the dust layer phenomenally one-dimensional. Another leg of the experiments have been carried out to investigate the effect of weathering of combustible dusts on their spontaneous ignition process. Two types of weathering methods, heat- and moisture-weathering are used. Sample preparation and weathering quantification methods follow the standard test procedure. Thermogravimetric analysis has been employed to understand the variation in weight loss of fresh, heat-weathered and moisture-weathered samples of coal and organic dusts. Preliminary results show that heat weathering increases the hazard level for organic (wheat) dust. In summary, the current research work mainly involves modification of the standard test method such as ASTM E-2021 to include an insulated ring instead of a metal ring to ensure one-dimensional heat transfer and extending the test method to include wedge-shaped geometries. The spontaneous ignition of combustible dust in the new setups is investigated thoroughly. Furthermore, mathematical and numerical models have been proposed to simulate the experimental tests. Finally, the effect of two types of weathering processes on the characteristics of spontaneous ignition has been studied. In all the cases, results are thoroughly discussed with the explanation of the physics involved.
24

Electronic correlations in few layer graphene

Zhang, Fan, 1983- 06 February 2012 (has links)
In this thesis we investigate the electronic band structures and the correlations in chirally (ABC) stacked N-layer graphene with N ≥ 2. We use ab initio density-functional theory and k · p theory to fit the parameters of a p-band tightbinding model. External potential differences between top and bottom layers are strongly screened by charge transfer but still open an energy gap at overall neutrality. Perpendicular magnetic field drives the system into the quantum Hall region with 4N-fold zero energy Landau levels. We predict that Coulomb interactions spontaneously break the SU(4N) symmetry and drive quantum Hall effects at all integer fillings n from −2N to 2N with exotic spin and pseudospin polarizations. Based on mean-field theory and perturbative renormalization group analysis, we predict that the ground state of bilayer graphene spontaneously breaks inversion symmetry for arbitrarily weak electron-electron interactions and conclude that this instability is not suppressed by quantum fluctuations but that, because of trigonal warping, it may occur only in high quality suspended bilayers. Remarkably flat conduction and valence bands that touch at charge neutrality point and Bloch states with large pseudospin chirality combine to make the bilayer graphene gapless band state strongly susceptible to a family of broken symmetry states in which each spinvalley flavor spontaneously transfers charge between layers. We explain how these states are distinguished by their charge, spin, and valley Hall conductivities, by their orbital magnetizations, and by their edge state properties. We further analyze how these competing states are influenced by Zeeman fields that couple to spin and by interlayer electric fields that couple to layer pseudospin, and comment on the possibility of using response and edge state signatures to identify the character of the bilayer ground state experimentally. We demonstrate that similar insulating broken symmetry states and spontaneous topological orders also occur in bilayer’s thicker cousins, chirally stacked multilayer graphene systems. / text
25

Tactical urbanism : from civil disobedience to civic improvement

Benner, Sophia Michelle 14 April 2014 (has links)
For the first time in the history of the Architecture Biennale the American Pavilion earned special recognition in 2012 for Spontaneous Interventions. The exhibition portrays an emerging phenomenon where citizen-led movements address urban problems with small-scale, low cost interventions. Sometimes sanctioned, sometimes not, the concept behind this movement has become known as tactical urbanism. This report examines the rise of tactical urbanism as an opportunity for the field of urban planning and describes how tactics can fit into the formal planning process. Currently, there exists a lack of understanding and research on the concept. This report contributes to the limited research by analyzing existing theory which discusses and supports the concept of tactical urbanism. After providing a theoretical foundation, four interventions displayed at the Biennale are reviewed to demonstrate the potential of this emerging approach. By evaluating the theoretical support behind tactical urbanism, the lacunae in planning literature, and the potential of this emerging approach as demonstrated by the four case studies, this report attempts to legitimize the discussion on tactical urbanism and identify how this emerging approach can fit into the formal planning process. / text
26

Norm evolution without the state : an examination of the unique nature of commercial law

Druzin, Bryan Howard 11 1900 (has links)
The discussion examines the idea that because of its relatively unique nature, commercial law has the distinct ability to evolve and function in the absence of a central coercive authority. While law of a non-commercial nature generally requires the backing of a state through which to derive its efficacy, a great deal of commercial law as it exists today evolves often in the absence of a single coercive authority, shaped largely by market forces outside the purview of any one state power. To this end, we look primarily at transnational commercial law, specifically at what is commonly understood as the new law merchant. It is the central contention of this paper that commercial law stands apart from other forms of law in that it is uniquely equipped to generate norms in situations where a single legislative power is notably not present, as it is largely impacted by the choices and behaviour of individual economic actors. We examine the notion that the manner of interaction implied by commercial intercourse involves a higher degree of overall engagement. This we term ‘high engagement’, which we divide into two elements: repetition and game creation, which with reciprocity, works in tandem to produce identifiable legal norms and the subsequent compliance with them. In Part I, after presenting a brief overview of the idea of reciprocity and spontaneous law theory, a more detailed explanation of the notion of engagement is offered. In Part II, we set out exactly how high engagement facilitates the development of and compliance with legal norms. Finally, the conclusion this paper reaches is that this element of high engagement, a salient characteristic of commercial interaction, plays a decisive role in the ability of commercial law to evolve and function in the vacuum of a central legislative authority.
27

Norm evolution without the state : an examination of the unique nature of commercial law

Druzin, Bryan Howard 11 1900 (has links)
The discussion examines the idea that because of its relatively unique nature, commercial law has the distinct ability to evolve and function in the absence of a central coercive authority. While law of a non-commercial nature generally requires the backing of a state through which to derive its efficacy, a great deal of commercial law as it exists today evolves often in the absence of a single coercive authority, shaped largely by market forces outside the purview of any one state power. To this end, we look primarily at transnational commercial law, specifically at what is commonly understood as the new law merchant. It is the central contention of this paper that commercial law stands apart from other forms of law in that it is uniquely equipped to generate norms in situations where a single legislative power is notably not present, as it is largely impacted by the choices and behaviour of individual economic actors. We examine the notion that the manner of interaction implied by commercial intercourse involves a higher degree of overall engagement. This we term ‘high engagement’, which we divide into two elements: repetition and game creation, which with reciprocity, works in tandem to produce identifiable legal norms and the subsequent compliance with them. In Part I, after presenting a brief overview of the idea of reciprocity and spontaneous law theory, a more detailed explanation of the notion of engagement is offered. In Part II, we set out exactly how high engagement facilitates the development of and compliance with legal norms. Finally, the conclusion this paper reaches is that this element of high engagement, a salient characteristic of commercial interaction, plays a decisive role in the ability of commercial law to evolve and function in the vacuum of a central legislative authority.
28

Spontaneous recovery in Pavlovian fear extinction and latent inhibition

Leung, Hiu Tin, Psychology, Faculty of Science, UNSW January 2009 (has links)
The experiments reported in the present thesis examined the behavioural processes of Pavlovian fear extinction and latent inhibition. The first series of experiments studied the reacquisition of extinguished fear responses following different amounts of extinction training. Rapid reacquisition occurred when rats were reconditioned after moderate extinction, showing that the original learning remained intact across this extinction. In contrast, when reconditioning was given after massive extinction, reconditioned responding was first depressed but then spontaneously recovered over time. This suggests that massive extinction produces a relatively permanent loss of the originally learned responding, while additionally imposes on the extinguished CS a transient latent inhibitory process that prevented the immediate but not the delayed expression of reconditioning. The second series of experiments studied the impact of spontaneous recovery of extinguished fear responses on their additional extinction. These experiments demonstrated that a CS that had time to show spontaneous recovery underwent greater response loss across additional extinction than one lacking recovery. They also showed that an excitor extinguished in compound with a CS showing recovery suffered greater response loss than an excitor extinguished in compound with a CS lacking recovery. Further, extinction of a compound composed of two CSs, one showing recovery and a second lacking recovery, produced greater extinction to the CS that showed recovery. These results show that spontaneous recovery of extinguished responses deepens their extinction through an error-correction mechanism regulated by both common and individual error terms. The third series of experiments studied the spontaneous recovery of latently inhibited and extinguished fear responses in within-subject designs. Using a compound test procedure, a CS that had received extensive preexposure or extensive extinction was found to have undergone greater spontaneous recovery relative to a CS just moderately preexposed or moderately extinguished. A CS given a mixed history of preexposure and extinction also underwent greater recovery relative to a CS just preexposed or just extinguished. These results suggest that both latent inhibition and extinction share a transient depressive process, and that the resulting recovery of responding is proportional to the amount of this depression.
29

Spontaneous recovery in Pavlovian fear extinction and latent inhibition

Leung, Hiu Tin, Psychology, Faculty of Science, UNSW January 2009 (has links)
The experiments reported in the present thesis examined the behavioural processes of Pavlovian fear extinction and latent inhibition. The first series of experiments studied the reacquisition of extinguished fear responses following different amounts of extinction training. Rapid reacquisition occurred when rats were reconditioned after moderate extinction, showing that the original learning remained intact across this extinction. In contrast, when reconditioning was given after massive extinction, reconditioned responding was first depressed but then spontaneously recovered over time. This suggests that massive extinction produces a relatively permanent loss of the originally learned responding, while additionally imposes on the extinguished CS a transient latent inhibitory process that prevented the immediate but not the delayed expression of reconditioning. The second series of experiments studied the impact of spontaneous recovery of extinguished fear responses on their additional extinction. These experiments demonstrated that a CS that had time to show spontaneous recovery underwent greater response loss across additional extinction than one lacking recovery. They also showed that an excitor extinguished in compound with a CS showing recovery suffered greater response loss than an excitor extinguished in compound with a CS lacking recovery. Further, extinction of a compound composed of two CSs, one showing recovery and a second lacking recovery, produced greater extinction to the CS that showed recovery. These results show that spontaneous recovery of extinguished responses deepens their extinction through an error-correction mechanism regulated by both common and individual error terms. The third series of experiments studied the spontaneous recovery of latently inhibited and extinguished fear responses in within-subject designs. Using a compound test procedure, a CS that had received extensive preexposure or extensive extinction was found to have undergone greater spontaneous recovery relative to a CS just moderately preexposed or moderately extinguished. A CS given a mixed history of preexposure and extinction also underwent greater recovery relative to a CS just preexposed or just extinguished. These results suggest that both latent inhibition and extinction share a transient depressive process, and that the resulting recovery of responding is proportional to the amount of this depression.
30

Spontaneous recovery in Pavlovian fear extinction and latent inhibition

Leung, Hiu Tin, Psychology, Faculty of Science, UNSW January 2009 (has links)
The experiments reported in the present thesis examined the behavioural processes of Pavlovian fear extinction and latent inhibition. The first series of experiments studied the reacquisition of extinguished fear responses following different amounts of extinction training. Rapid reacquisition occurred when rats were reconditioned after moderate extinction, showing that the original learning remained intact across this extinction. In contrast, when reconditioning was given after massive extinction, reconditioned responding was first depressed but then spontaneously recovered over time. This suggests that massive extinction produces a relatively permanent loss of the originally learned responding, while additionally imposes on the extinguished CS a transient latent inhibitory process that prevented the immediate but not the delayed expression of reconditioning. The second series of experiments studied the impact of spontaneous recovery of extinguished fear responses on their additional extinction. These experiments demonstrated that a CS that had time to show spontaneous recovery underwent greater response loss across additional extinction than one lacking recovery. They also showed that an excitor extinguished in compound with a CS showing recovery suffered greater response loss than an excitor extinguished in compound with a CS lacking recovery. Further, extinction of a compound composed of two CSs, one showing recovery and a second lacking recovery, produced greater extinction to the CS that showed recovery. These results show that spontaneous recovery of extinguished responses deepens their extinction through an error-correction mechanism regulated by both common and individual error terms. The third series of experiments studied the spontaneous recovery of latently inhibited and extinguished fear responses in within-subject designs. Using a compound test procedure, a CS that had received extensive preexposure or extensive extinction was found to have undergone greater spontaneous recovery relative to a CS just moderately preexposed or moderately extinguished. A CS given a mixed history of preexposure and extinction also underwent greater recovery relative to a CS just preexposed or just extinguished. These results suggest that both latent inhibition and extinction share a transient depressive process, and that the resulting recovery of responding is proportional to the amount of this depression.

Page generated in 0.0503 seconds