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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.
551

Smoking and Nicotine Dependence

Nelson, Christopher B., Wittchen, Hans-Ulrich 03 December 2012 (has links) (PDF)
This paper describes the distribution of dependence criteria and diagnoses in a sample of 14- to 24-year-olds from Munich, Germany (n = 3,021; 71% response rate), evaluates differences between nondependent and dependent smokers and examines associations of smoking with other substances, affective and anxiety disorders. Assessment was made using the M-CIDI. The lifetime prevalence of DSM-IV nicotine dependence in the total sample is 19%, rising to 52% among regular smokers. No gender differences were seen in the progression from regular smoking to nicotine dependence, although men were more likely than women to initiate regular use. Analysis of daily cigarette use identified a significant dose-response relationship with the number of endorsed DSM-IV dependence criteria with unsuccessful cut-backs being the most prevalent criterion. As compared to nondependent smokers, dependent smokers were more likely to associate negative health effects with smoking and to have a desire to change and attempt a change in their pattern of use. Regular use of nicotine was found to be significantly associated with other substance and nonsubstance disorders, although dependent regular use was more strongly associated with these disorders than nondependent regular use. These results indicate that daily smoking is a behavior which is resistant to change despite an expressed desire and repeated cut-back attempts. Although initiation of regular smoking among nonsmokers does not occur frequently after the early twenties, the risk for dependent smoking among regular users persists into adulthood and is associated with a range of mental disorders.
552

Patterns of Use and Their Relationship to DSM-IV Abuse and Dependence of Alcohol among Adolescents and Young Adults

Holly, Alexandra, Wittchen, Hans-Ulrich 22 November 2012 (has links) (PDF)
First use and initiation of regular alcohol use has been frequently found to start in adolescence. However, only few studies have also investigated how many adolescents proceed during ages 14–24 to harmful drinking or even develop alcohol use disorders. This paper – using the EDSP baseline sample of 3,021 community respondents from the Munich area – examines the prevalence of use, abuse and dependence and investigates the dose/disorder relationship. Alcohol abuse was reported by 9.7% of respondents and alcohol dependence by 6.2%. Men were more likely to report an alcohol disorder than women, prevalence also increased in the older age cohorts. However, even among 14- to 17-year-olds a substantial proportion of respondents report high and regular consumption rates, the occurrence of abuse and dependence criteria and even a full dependence syndrome. There is however only a moderate association between average number of standard drinks consumed with the risk of developing abuse and dependence. In light of the substantial rates among adolescents and young adults the validity of DSM-IV alcohol disorder criteria is discussed.
553

Politisk integration och gränsöverskridande regionbildning i Europa / Political integration and cross-border region-building in Europe

Östhol, Anders January 1996 (has links)
This study starts out with the hypothesis that the integration process in Europe is connected to cross-border régionalisation, a process which supports the institutionalization of subnational cross-border cooperation - region-building. Cross-border régionalisation is characterized by the decentralisation of vertical links and enhanced opportunities for horizontal links across state borders. In addition, political integration is expected to have some impact on the cross-border institutional forms that emerge at the subnational level. Three different approaches are utilized in order to establish the empirical connection between political integration and region-building. These are: an analysis of the factors which determine the general pattern of cross-border cooperation in Europe, an analysis of the policy network related to the regional and structural policies of the European Union (EU), and case studies of cooperation in the heartland of Europe, the Regio Basiliensis along the external border of the EU, and the EUREGIO along one of the internal borders. Two institutional factors are found to have a significant impact on the number of subnational cross-border cooperations, EU-membership and centrality. Federal constitution was shown not to be significant. It is suggested that the interaction between actors at different politico- administrative levels creates network relations, which typically bring both private and public actors together. More precisely, region-building is described as the outcome of the interaction which takes place between actors. A closer examination of the emerging policy network shows that community initiatives, the Interreg-programme in particular, improve the prospects for multi­level interaction. The EU plays a crucial role in providing the incentives for cooperation by increasing resource dependency and by establishing direct ties between the European Commission and a large number of subnational actors through partnerships. It appears as if the Commission wishes to demonstrate its capacity to deal with problems relevant to individual citizens. By, in part, bypassing central governments, it seems to increase its own importance vis- à-vis member states. The modus vivendi of cross-border region-building and régionalisation is the degree to which institutional actors at different levels share the same objectives. As shown by the case studies, there is a common interest in cross-border cooperation up to the point were public statues are introduced. Interests seem to coincide as long as the structures and contents of cross-border cooperation do not ultimately challenge the authority of state institutions. Therefore, it is not surprising that it seems impossible to give cross-border regions any rights under international law. Functional cooperation, rather than regionalist manifestations of cultural or political unity across borders, constitutes the backbone of region-building. Activities transcending borders are less controversial than those that may contribute to the establishment of new borders. It is concluded that region-building is a process which is embedded in the institutionalization of a multi-level interaction pattern. More favourable multilevel relations have been achieved through the transfer of some authority to the supranational level. This is the main reason why traditional integration theory fails to explain why there is a connection between political integration and cross-border cooperation. / digitalisering@umu
554

Prävalenz von Alkoholkonsum, Alkoholmißbrauch und -abhängigkeit bei Jugendlichen und jungen Erwachsenen / Prevalence of alcohol use, abuse and dependence in adolescents and young adults

Holly, Alexandra, Türk, Dilek, Nelson, Christopher B., Pfister, Hildegard, Wittchen, Hans-Ulrich 23 October 2012 (has links) (PDF)
Alkoholkonsum beginnt häufig bereits im Jugendalter. Allerdings fehlen bisher Erkenntnisse darüber, ob, wie häufig und aufgrund welcher Merkmale Jugendlichen und junge Erwachsene auch bereits klinisch definierte Mißbrauchs- und Abhängigkeitsdiagnosen entwickeln. In der vorliegenden Arbeit werden Ergebnisse einer repräsentativen Untersuchung an 3021 Jugendlichen im Alter von 14-24 Jahren vorgestellt. Neben der Prävalenz von Alkoholmißbrauch und -abhängigkeit nach DSM-IV werden Daten zur Häufigkeit und Menge des Alkoholkonsums berichtet sowie erste Symptome beschrieben. 9,7% der befragten Jugendlichen erhielten aufgrund von DSM-IV-Kriterien eine Mißbrauchsdiagnose, 6,2% eine Abhängigkeitsdiagnose. Bei männlichen Jugendlichen war die Prävalenz wesentlich höher als bei weiblichen. Die Prävalenz war in den älteren Geburtskohorten höher. Als erstes Missbrauchssymptom trat am häufigsten "Gebrauch mit körperlicher Gefährdung" (91,9%), als erstes Abhängigkeitssymptom "Toleranzentwicklung" (34,3%) auf. Erste diagnostische Kriterien einer Alkoholstörung traten zumeist deutlich vor dem 18. Lebensjahr auf. Diese Daten unterstreichen, daß Alkoholmißbrauch und -abhängigkeit bereits im Jugend- und frühen Erwachsenenalter häufig sind. / Alcohol use frequently begins in adolescence. However, only few studies have reported the prevalence of alcohol abuse disorders in adolescents. This paper reports results from a representative study in a sample of 3021 adolescents, aged 14-24 years. The Prevalence of alcohol abuse and dependence according to DSM-IV criteria, as well as the prevalence, frequency and quantity of alcohol abuse and a description of the first occuring symptoms, are presented here. Alcohol abuse was reported by 9.7% of respondents and alcohol dependence by 6.2%. Males were more likely to report an alcohol disorder than females, and the prevalence also increased in the older age cohorts. The most frequent initial symptoms were "hazardous use" (91.9%) for abuse and "tolerance" (34.3%) for dependence. First symptoms have been shown to occur long before the age of 18. These results show that even in adolescents and young adults alcohol abuse and dependence are frequent disorders.
555

Field sensitivity of Native American students at Oregon State University, as determined by the group embedded figures test

Pelto, Joan McAlmond 08 February 1991 (has links)
Historically, Native American students have not achieved academic success; ethnic and racial stereotypes are common explanations for the problem. Many perceive the Native American student to be lacking either academic preparation or socio-cultural support for success. A review of the literature showed emerging research which indicates that significant differences can be shown between the learning styles of Native American students and their non-Native counterparts. It has been claimed that these differences may account for some of the differences in academic achievement. The purpose of this study was an attempt to document more thoroughly the differences between the learning styles of Native American and non-Native university students, employing the Group Embedded Figures Test (GEFT). The GEFT measures degree of field sensitivity, a measure of the degree to which an individual is affected by the surrounding environment or situation within which learning is to take place. It has been postulated that Native American children tend to be reared in a culture which promotes field dependent learning styles. Conversely, children reared in families promoting strong individual identity tend to be more field independent. The results of administering the GEFT to a group of Native American university students and to a comparison group of non-Native students supported the theory. A numerical difference of 2.1, on a scale of 1 to 18, was found between the mean scores of the two study groups with the Native American students scoring in the more field dependent domain. The mean score for the Native American student study group was 9.7, while that for the comparison group was 11.8. In addition to ethnic differences, the data from this study showed differences from previously established norms both by age and gender. Based on the results of this study, educators may be urged to consider the style in which a student learns before categorizing him or her as academically deficient. Further study of learning styles of Native American students and concommitantly of teaching styles which are best suited to Native American students is recommended. / Graduation date: 1991
556

A New Theory Of Content

Aytekin, Tevfik 01 September 2003 (has links) (PDF)
Naturalistic philosophers of meaning try to define the recalcitrant concept of reference in terms respected by the empirical science, such as causality or teleology. In this thesis, after a brief introduction to these trials is given, Fodors theory of content in terms of asymmetric dependence is examined in some depth. I claim that although this theory involves an important insight, it is an unsatisfactory attempt at reduction of the notion of reference. I develop a new theory of content, which does not have the defects of the analyses in terms of asymmetric dependence, and more successfully deals with notorious cases, such as pansemanticism and the possibility of misrepresentation.
557

Simulation models for estimating productivity and trade-offs in the data-limited fisheries of New South Wales, Australia

Forrest, Robyn Elizabeth 05 1900 (has links)
Recent shifts towards ecosystem based fisheries management (EBFM) around the world have necessitated consideration of effects of fishing on a larger range of species than previously. Non-selective multispecies fisheries are particularly problematic for EBFM, as they can contribute to erosion of ecosystem structure. The trade-off between catch of productive commercial species and abundance of low-productivity species is unavoidable in most multispecies fisheries. A first step in evaluation of this trade-off is estimation of productivity of different species but this is often hampered by poor data. This thesis develops techniques for estimating productivity for data-limited species and aims to help clarify EBFM policy objectives for the fisheries of New South Wales (NSW), Australia. It begins with development of an age-structured model parameterised in terms of optimal harvest rate, UMSY. UMSY is a measure of productivity, comparable among species and easily communicated to managers. It also represents a valid threshold for prevention of overfishing. The model is used to derive UMSY for 54 Atlantic fish stocks for which recruitment parameters had previously been estimated. In most cases, UMSY was strongly limited by the age at which fish were first caught. However, for some species, UMSY was more strongly constrained by life history attributes. The model was then applied to twelve species of Australian deepwater dogshark (Order Squaliformes), known to have been severely depleted by fishing. Results showed that the range of possible values of UMSY for these species is very low indeed. These findings enabled a preliminary stock assessment for three dogsharks (Centrophorus spp.) currently being considered for threatened species listing. Preliminary results suggest they have been overfished and that overfishing continues. Finally, an Ecopath with Ecosim ecosystem model, representing the 1976 NSW continental slope, is used to illustrate trade-offs in implementation of fishing policies under alternative policy objectives. Results are compared with those of a biogeochemical ecosystem model (Atlantis) of the same system, built by scientists from CSIRO. While there were large differences in model predictions for individual species, they gave similar results when ranking alternative fishing policies, suggesting that ecosystem models may be useful for exploring broad-scale strategic management options.
558

Notions of Dependence with Applications in Insurance and Finance

Wei, Wei January 2013 (has links)
Many insurance and finance activities involve multiple risks. Dependence structures between different risks play an important role in both theoretical models and practical applications. However, stochastic and actuarial models with dependence are very challenging research topics. In most literature, only special dependence structures have been considered. However, most existing special dependence structures can be integrated into more-general contexts. This thesis is motivated by the desire to develop more-general dependence structures and to consider their applications. This thesis systematically studies different dependence notions and explores their applications in the fields of insurance and finance. It contributes to the current literature in the following three main respects. First, it introduces some dependence notions to actuarial science and initiates a new approach to studying optimal reinsurance problems. Second, it proposes new notions of dependence and provides a general context for the studies of optimal allocation problems in insurance and finance. Third, it builds the connections between copulas and the proposed dependence notions, thus enabling the constructions of the proposed dependence structures and enhancing their applicability in practice. The results derived in the thesis not only unify and generalize the existing studies of optimization problems in insurance and finance, but also admit promising applications in other fields, such as operations research and risk management.
559

Die unzureichende Beteiligung von Psychiatern an der Subsitutionsbehandlung / Insufficient involvement of psychiatrists in substitution treatment

Soyka, Michael, Apelt, Sabine M., Wittchen, Hans-Ulrich 20 February 2013 (has links) (PDF)
Ergebnisse einer breit angelegten Repräsentativerhebung zur Substitutionstherapie in Deutschland an 2694 Patienten zeigen, dass trotz hoher und komplexer Ko- und Multimorbidität mit psychischen Erkrankungen nur selten Psychiater an der Therapie beteiligt sind. Nur 16% der Substitutionsärzte (n=223) sind Psychiater oder Psychotherapeuten und nur 21% der substituierten Drogenabhängigen werden von Psychiatern behandelt. Die meisten substituierenden Psychiater sind in Institutsambulanzen psychiatrischer Kliniken tätig (51,3%), kaum in eigener Praxis (7,2%). Der Großteil der Substitutionsversorgung wird von Allgemein- und Hausärzten geleistet. Die relative Abstinenz psychiatrischer Kollegen bei der Substitution drogenabhängiger Patienten wird kritisch diskutiert. / Results of a nationally representative study in 2,694 patients reveal that most physicians (n=223) involved in substitution treatment of opioid-dependent patients are general practitioners, while only 16% have a psychiatric/psychotherapeutic background and only 21% of the addictive patients are treated by psychiatrists. This contrasts with the remarkably complex pattern of co- and multimorbidity with other mental disorders in such patients. Most psychiatrists engaged in substitution treatment work in specialized outpatient wards (51.3%), and few were operative in their own or private practice (7.2%). Implications of these critical findings are discussed.
560

Metoder för aktivitetstest av anammox och ammoniakoxiderande bakterier på bärarmaterial / Methods for Activity Tests of Anammox and Ammonia Oxidizing Bacteria on Carrier Material

Gustafsson, Ida January 2013 (has links)
I och med övergödningsproblematiken i Östersjön och Sveriges åtaganden i samband med Baltic Sea Action Plan kommer det i framtiden ställas högre krav på rening av kväve från de större avloppsreningsverken i Sverige. Anammox är processen där ammonium oxideras till kvävgas med nitrit som elektonacceptor. Anammox har under den senare tiden implementerats för rejektvattenbehandling i avloppsreningsverk runt om i världen.  När anammox används för att rena ammonium krävs att ca hälften av inkommande ammonium oxideras till nitrit genom nitritation. Detta steg utförs av ammoniakoxiderande bakterier (AOB) vilka kräver en aerob miljö. Den kombinerade processen med anammox och nitritation kallas deammonifikation. På Sjölunda avloppsreningsverk i Malmö har en pilotstudie, i sammarbete med VA-teknik på Lunds Tekniska Högskola, startats för att undersöka potentialen i att implementera deammonifikation i huvudströmmen på reningsverket. Detta examensarbete har syftat till att utarbeta metoder för aktivitetstest av anammox och AOB på bärarmaterial från pilotanläggningen. Med de utarbetade metoderna studerades sedan anammoxbakteriernas aktivitet vid förändrad temperatur. Eftersom anammox producerar kvävgas kunde en metod som baseras på tryckmätning utarbetas för att bestämma anammoxaktiviteten. Metoden visade sig vara tidseffektiv och enkel att utföra. I examensarbetet framkom resultat som visar på att anammox­aktiviteten är beroende av startkoncentrationen av nitrit vid startkoncentrationer under 75 milligram kväve per liter (mg N/l). Beroendet följer av diffusionsbegränsningar i biofilmen vid lägre koncentrationer. Vid startkoncentrationer i intervallet 75-150 mg N/l var aktiviteten oberoende av startkoncentrationen. Vid koncentrationer över 150 mg N/l konstaterades en aktivitetsminskning som troligtvis beror på nitritinhibering. Metoden som arbetades fram för aktivitetstest av AOB baserades på att mäta syrerespirationen innan och efter tillsats av ammonium i en alternerande syresatt reaktor. I metoden skulle en inhibitor för nitritoxiderande bakterier, NaClO3, tillsättas vid slutet av försöket för att säkerställa att dessa bakterier inte konsumerar syre och därmed påverkar resultatet. Vid tillsats av inhibitorn uppstod en orimligt stor aktivitetsförlust som tyder på att denna även inhiberar AOB.  Anammoxaktivitetens temperaturberoende analyserades genom aktivitetsmätning vid fyra temperaturer, i intervallet 11,1-24,9 °C. Försöken visade att förhållandet var exponentiellt och att vid en temperatursänkning från 24,9 °C till 11,1 °C förloras 93 % av aktiviteten. / Given the problem with eutrophication in the Baltic Sea and Sweden's obligations in the Baltic Sea Action Plan, a higher requirement on the removal of nitrogen from the major wastewater treatment plants is expected to be set in the future. Anammox is the process where ammonium is oxidized to nitrogen gas with nitrite as electron acceptor. Anammox has been implemented for treatment of the sludge liquor in wastewater treatment plants around the world. When anammox is used to reduce ammonium, the process requires about half the incoming ammonium to be oxidized into nitrite. This is conducted by ammonia oxidizing bacteria (AOB) that require an aerobic environment. The combined process with anammox and nitritation is called deammonification. A pilot study is taking place at Sjölunda Wastewater Treatment Plant in Malmö in collaboration with Water and Environmental Engineering, Department of Chemical Engineering, Lund University. The aim of the pilot study is to explore the potential of implementing deammonification in the main stream at the wastewater treatment plant. The aim of this Master Theisis is to develop methods for activity tests of Anammox and AOB on carrier material. The elaborated methods were then supposed to be used to study the change in activity with decreasing temperature.  Since anammox produces nitrogen gas a method based on pressure measurements was developed to determine the anammox activity. The results in this thesis showed that the anammox activity was dependent of the initial concentration of nitrite at concentrations below 75 mg N / L. This dependence is a result of the limitations of the diffusion in the biofilm at low concentrations. When the initial concentration of nitrite was within the range of 75 to 150 mg N / L the activity was independent of the initial concentration. At concentrations above 150 mg N / L there was a decrease in activity which probably occurred as a result of nitrite inhibition. To determine the activity of AOB a method based on the oxygen consumption rate was developed. The aeration switched between being turned on and off every five minutes and after some rounds of aereation, ammonium was added. The AOB activity was determined by calculating the difference between the oxygen consumption before and after the addition of ammonium. To ensure that nitrite-oxidizing bacteria (NOB) were not consuming any oxygen, NaClO3 was added at the end of the experiment. The resulting decrease in activity was too excessive to only represent the activity loss from only NOB which may suggest that NaClO3 also inhibits AOB. The temperature dependence of anammox activity was analyzed in activity tests at four temperatures in the range of 11.1 to 24.0°C. The experiments concluded that the relationship was exponential and by a drop in temperature from 24.9 ° C to 11.1 °C 93% of the activity was lost.

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