733 resultados para pneumatic dilatation


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OBJECTIVE: To evaluate the association between tourniquet and total operative time during total knee arthroplasty and the occurrence of deep vein thrombosis. METHODS: Seventy-eight consecutive patients from our institution underwent cemented total knee arthroplasty for degenerative knee disorders. The pneumatic tourniquet time and total operative time were recorded in minutes. Four categories were established for total tourniquet time: <60, 61 to 90, 91 to 120, and >120 minutes. Three categories were defined for operative time: <120, 121 to 150, and >150 minutes. Between 7 and 12 days after surgery, the patients underwent ascending venography to evaluate the presence of distal or proximal deep vein thrombosis. We evaluated the association between the tourniquet time and total operative time and the occurrence of deep vein thrombosis after total knee arthroplasty. RESULTS: In total, 33 cases (42.3%) were positive for deep vein thrombosis; 13 (16.7%) cases involved the proximal type. We found no statistically significant difference in tourniquet time or operative time between patients with or without deep vein thrombosis. We did observe a higher frequency of proximal deep vein thrombosis in patients who underwent surgery lasting longer than 120 minutes. The mean total operative time was also higher in patients with proximal deep vein thrombosis. The tourniquet time did not significantly differ in these patients. CONCLUSION: We concluded that surgery lasting longer than 120 minutes increases the risk of proximal deep vein thrombosis.

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Objective: Enhanced sodium intake increases volume overload, oxidative stress and production of proinflammatory cytokines. In animal models, increased sodium intake favours ventricular dysfunction after myocardial infarction (MI). The aim of this study was to investigate, in human subjects presenting with ST-segment elevation MI (STEMI), the impact of sodium intake prior the coronary event. Methods: Consecutive patients (n = 372) admitted within the first 24 h of STEMI were classified by a food intake questionnaire as having a chronic daily intake of sodium higher (HS) or lower (LS) than 1.2 g in the last 90 days before MI. Plasma levels of 8-isoprostane, interleucin-2 (IL-2), tumour necrosis factor type alpha (TNF-alpha), C-reactive protein (CRP) and brain natriuretic peptide (BNP) were measured at admission and at the fifth day. Magnetic resonance imaging was performed immediately after discharge. Total mortality and recurrence of acute coronary events were investigated over 4 years of follow-up. Results: The decrease of 8-isoprostane was more prominent and the increase of IL-2, TNF-alpha and CRP less intense during the first 5 days in LS than in HS patients (p < 0.05). Sodium intake correlated with change in plasma BNP between admission and fifth day (r = 0.46; p < 0.0001). End-diastolic volumes of left atrium and left ventricle were greater in HS than in LS patients (p < 0.05). In the first 30 days after MI and up to 4 years afterwards, total mortality was higher in HS than in LS patients (p < 0.05). Conclusion: Excessive sodium intake increases oxidative stress, inflammatory response, myocardial stretching and dilatation, and short and long-term mortality after STEMI. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

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Abstract Background Forearm blood flow responses during mental stress are greater in individuals homozygous for the Glu27 allele. A high-fat meal is associated with impaired endothelium-dependent dilatation. We investigated the impact of high-fat ingestion on the muscle vasodilatory responses during mental stress in individuals with the Glu27 allele and those with the Gln27 allele of the β2-adrenoceptor gene. Methods A total of 162 preselected individuals were genotyped for the Glu27Gln β2-adrenoceptor polymorphism. Twenty-four individuals participated in the study. Fourteen were homozygous for the Gln27 allele (Gln27Gln, 40 ± 2 years; 64 ± 2 kg), and 10 were homozygous for the Glu27 allele (Glu27Glu, 40 ± 3 years; 65 ± 3 kg). Forearm blood flow was evaluated by venous occlusion plethysmography before and after ingestion of 62 g of fat. Results The high-fat meal caused no changes in baseline forearm vascular conductance (FVC, 2.2 ± 0.1 vs. 2.4 ± 0.2; P = 0.27, respectively), but reduced FVC responses to mental stress (1.5 ± 0.2 vs. 0.8 ± 0.2 units; P = 0.04). When volunteers were divided according to their genotypes, baseline FVC was not different between groups (Glu27Glu = 2.4 ± 0.1 vs. Gln27Gln = 2.1 ± 0.1 units; P = 0.08), but it was significantly greater in Glu27Glu individuals during mental stress (1.9 ± 0.4 vs. 1.0 ± 0.3 units; P = 0.04). High-fat intake eliminated the difference in FVC responses between Glu27Glu and Gln27Gln individuals (FVC, 1.3 ± 0.4 vs. 1.2 ± 0.4; P = 0.66, respectively). Conclusion These findings demonstrate that a high-fat meal impairs muscle vasodilatation responses to mental stress in humans. However, this reduction can be attributed to the presence of the homozygous Glu27 allele of the β2-adrenoceptor gene.

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Abstract Introduction Endometrial ossification is an uncommon disease related to secondary infertility and its etiology and pathogenesis are controversial. More than 80% of reported cases occur after pregnancy. Case presentation A 33-year-old Caucasian woman was admitted with a history of secondary infertility and with a regular menstrual cycle. She reported a miscarriage at 12 weeks of gestation 7 years previously and subsequent dilatation and curettage in another medical facility. Vaginal ultrasound was performed and showed an intrauterine structure described as a hyperechogenic image suggesting calcification related to chronic endometritis. Office hysteroscopy revealed a wide endometrial cavity and proliferative endometrium, with a coral-like white plaque 1.5 cm in length on the right horn and posterior wall of the uterus. The lesion was treated by hysteroscopy without complications. Microscopic examination showed endometrial tissue with osseous metaplasia in the stroma. Nine months after the procedure, the patient became pregnant spontaneously. Conclusion In our patient, hysteroscopy was effective in the diagnosis and treatment of osseous metaplasia of the endometrium associated with infertility.

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O objetivo do presente trabalho foi comparar duas sequências diferentes na rapidez e segurança no preparo de canais curvos simulados. Foram empregados 30 blocos de acrílico com canais simulados que foram divididos em Grupo 1 – La Axxess 20 e 35/.06 25/.06, 20/.06, 25/.04 e 20/.04 e Grupo 2 – K3 Universal (VTVT) – 25/.10, 25/.08, 35/.06, 30/.04, 25/.06 e 20/.04. No preparo de todos os blocos empregou-se a velocidade de 250 rpm e torque de 1.4N/cm. Foram confeccionados dois pontos externos de amálgama para mensuração do desvio e adotou-se 17 mm como comprimento de trabalho. No Grupo 1, dilatou-se até o instrumento 25/.04, enquanto que no Grupo 2 até o 25/.06, e cronometrou-se o tempo de preparo de cada bloco. Na análise do desvio, radiografias com lima k 15 (antes) e K 25 (depois) foram realizadas e digitalizadas, medindo-se o ângulo antes e depois no programa Digora for Windows 1.51. Os dados foram comparados pelo teste T-Student e Mann-Whitney. Os resultados mostraram que em ambas as técnicas não ocorreram diferenças significantes entre o ângulo antes e depois e que não ocorreu diferença significante entre os desvios médios do Grupo 1 (0,130) e do Grupo 2 (1,330). No tempo de preparo, o Grupo 1 foi significantemente mais rápido que o Grupo 2. No Grupo 1, ocorreu a fratura de 1 instrumento, enquanto que no Grupo 2 ocorrerem duas fraturas. Concluiu-se que ambas as técnicas são seguras para o preparo de canais simulados curvos, sendo que no Grupo 1 o tempo de preparo é menor.

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JUSTIFICATIVA E OBJETIVOS: Durante o processo de parturição, diversos fatores alteram a intensidade da dor, tais como a paridade, a rotura de membranas corioamnióticas, a dilatação cervical, bem como influências culturais e ambientais. Assim, os objetivos deste estudo foram verificar o número de requisições de analgesia regional e o grau de dilatação cervical no momento da solicitação da analgesia pelas parturientes com membranas corioamnióticas íntegras e aquelas com corioamniorrexe. MÉTODO: Trata-se de um estudo descritivo e retrospectivo, com análise de 208 prontuários de parturientes primigestas, 129 com membranas corioamnióticas íntegras e 79 com corioamniorrexe, assistidas no Centro da Saúde da Mulher de Ribeirão Preto, SP, no período de novembro de 2008 a maio de 2009. Para análise estatística dos dados foram utilizados os testes de Mann-Whitney e o Qui-quadrado, com nível de significância p < 0,05 e intervalo de confiança de 95%. RESULTADOS: Foi solicitada analgesia regional por 87,9% das parturientes selecionadas para esta pesquisa. A média da dilatação cervical para as pacientes com membranas íntegras foi de 6,26 ± 1,67 cm e para aquelas com corioamniorrexe foi com dilatação de 6,11 ± 1,75 cm, não havendo diferença significativa entre esses dois grupos de parturientes (p = 0,12). Em relação ao tipo de analgesia, houve predomínio do duplo bloqueio, sem diferenças significativas entre os dois grupos avaliados (p = 0,84). CONCLUSÃO: A maioria das parturientes deste estudo solicitou analgesia regional tipo duplo bloqueio com em média 6 cm, de acordo com a dilatação cervical, não havendo diferença entre primigestas com membranas corioamnióticas rotas e íntegras.

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Although it is known that obesity, diabetes, and Kawasaki's disease play important roles in systemic inflammation and in the development of both endothelial dysfunction and cardiomyopathy, there is a lack of data regarding the endothelial function of pre-pubertal children suffering from cardiomyopathy. In this study, we performed a systematic review of the literature on pre-pubertal children at risk of developing cardiomyopathy to assess the endothelial function of pre-pubertal children at risk of developing cardiomyopathy. We searched the published literature indexed in PubMed, Bireme and SciELO using the keywords 'endothelial', 'children', 'pediatric' and 'infant' and then compiled a systematic review. The end points were age, the pubertal stage, sex differences, the method used for the endothelial evaluation and the endothelial values themselves. No studies on children with cardiomyopathy were found. Only 11 papers were selected for our complete analysis, where these included reports on the flow-mediated percentage dilatation, the values of which were 9.80±1.80, 5.90±1.29, 4.50±0.70, and 7.10±1.27 for healthy, obese, diabetic and pre-pubertal children with Kawasaki's disease, respectively. There was no significant difference in the dilatation, independent of the endothelium, either among the groups or between the genders for both of the measurements in children; similar results have been found in adolescents and adults. The endothelial function in cardiomyopathic children remains unclear because of the lack of data; nevertheless, the known dysfunctions in children with obesity, type 1 diabetes and Kawasaki's disease may influence the severity of the cardiovascular symptoms, the prognosis, and the mortality rate. The results of this study encourage future research into the consequences of endothelial dysfunction in pre-pubertal children.

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Background/objectives: Therapy using bone marrow (BM) cells has been tested experimentally and clinically due to the potential ability to restore cardiac function by regenerating lost myocytes or increasing the survival of tissues at risk after myocardial infarction (MI). In this study we aimed to evaluate whether BM-derived mononuclear cell (MNC) implantation can positively influence the post-MI structural remodeling, contractility and Ca(2 +)-handling proteins of the remote non-infarcted tissue in rats. Methods and results: After 48 h of MI induction, saline or BM-MNC were injected. Six weeks later, MI scars were slightly smaller and thicker, and cardiac dilatation was just partially prevented by cell therapy. However, the cardiac performance under hemodynamic stress was totally preserved in the BM-MNC treated group if compared to the untreated group, associated with normal contractility of remote myocardium as analyzed in vitro. The impaired post-rest potentiation of contractile force, associated with decreased protein expression of the sarcoplasmic reticulum Ca2 +-ATPase and phosphorylated-phospholamban and overexpression of Na(+)/Ca(2 +) exchanger, were prevented by BM-MNC, indicating preservation of the Ca(2 +) handling. Finally, pathological changes on remodeled remote tissue such as myocyte hypertrophy, interstitial fibrosis and capillary rarefaction were also mitigated by cell therapy. Conclusions: BM-MNC therapy was able to prevent cardiac structural and molecular remodeling after MI, avoiding pathological changes on Ca(2 +)-handling proteins and preserving contractile behavior of the viable myocardium, which could be the major contributor to the improvements of global cardiac performance after cell transplantation despite that scar tissue still exists.

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Introdução: Trombose Venosa Profunda (TVP) é o resultado de inúmeros fatores, incluindo estase venosa, injuria endotelial e hipercoagulação do sangue. O embolismo pulmonar é a maior complicação da TVP e ocorre quando um trombo ou um coágulo sangüíneo desloca-se em direção aos pulmões. O tromboembolismo é um sério problema de saúde e é responsável por um considerável número de mortes súbitas e por significantes custos de hospitalizações em todo o mundo. Entre os métodos profiláticos usados na prevenção da TVP, há os classificados como mecânicos e os farmacológicos. Ambos são efetivos e podem ser usados sempre que necessário, tendo sido recomendados por consenso internacional. Objetivos: Avaliar a incidência da TVP em pacientes cirúrgicos através da Compressão pneumática Intermitente CPI (coxa/perna ou perna/pé) contra nenhuma forma de profilaxia ou contra fármacos. Métodos: Revisão sistemática de ensaios clínicos randomizados, utilizando a metodologia Cochrane, através de buscas eletrônica e manual. Foram incluídos pacientes cirúrgicos, de ambos os sexos, cuja intervenção foi o uso de aparelhos de compressão pneumática intermitente. Resultados: 4269 pacientes cirúrgicos investigados por 31 ensaios submetidos a um número de intervenções cirúrgicas, incluindo cirurgia ortopédica (joelho e quadris), geral, ginecológica, urológica e neurológica. Dados combinados demonstraram efeitos de tratamento virtualmente iguais entre CPI e abordagens farmacológicas [0.95 (95%CI 0.82, 1.10)], em relação à incidência de TVP. Entretanto, o risco de hemorragia foi maior e estatisticamente significante em pacientes tratados com intervenções farmacológicas [0.37(95%CI 0.20, 0.69)]. Conclusão: Comparações entre as estratégias farmacológicas e mecânicas indicam que ambas são similares na prevenção de trombose venosa profunda. Entretantio, a evidência atual suportaria a escolha das abordagens mecâncias, uma vez que o risco de eventos hemorrágicos favorece os métodos mecânicos.

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Extensive literature outlined that the quality of the mother-foetus relationship is considered the main feature with regard to the quality of postnatal mother-infant interaction and also to the child’s psychical development. Nowadays the relationship between the pregnant woman and her foetus is viewed as the central factor of the somatic dialogue between the functioning of the maternal and the foetal organisms. This dialogue is responsible for the physic development of the child, as well as of its psychosomatic structure. Therefore the research area has necessarily had to extend to the analysis of psychological processes concerning: the pregnancy, the couple that is bound by parenthood, the influence of intergenerational dynamics. In fact, the formation of maternal identity, as well as that of the relationship between the woman and the foetus, refers to the pregnant woman’s relationship with her parents, especially with her mother. The same pregnancy, considered as a psychosomatic event, is directly influenced by relational, affective and social factors, particularly by the quality of the interiorized parental relations and the quality of the current relationships (such as that with her partner and with her family of origin). Some studies have begun to investigate the relationship between the pregnant woman and the foetus in term of “prenatal attachment” and its relationship with socio-demographic, psychological e psychopathological aspects (such as pre and post partum depression), but the research area is still largely unexplored. The present longitudinal research aimed to investigate the quality of the pregnant womanfoetus relationship by the prenatal attachment index, the quality of the interiorized relationship with woman’s parents, the level of alexithymic features and maternity social support, in relation with the modulation of the physiology of delivery and of postpartum, as well as of the physical development of the child. A consecutive sample of 62 Italian primipara women without any kind of pathologies, participated in the longitudinal study. In the first phase of this study (third trimester of the pregnancy), it has investigated the psychological processes connected to the affective investment of the pregnant women towards the unborn baby (by Prenatal Attachment Inventory), the mothers’ interiorized relationship with their own parents (by Parental Bonding Instrument), the social and affective support from their partner and their family of origin are able to supply (by Maternity Social Support Scale), and the level of alexithymia (by 20-Toronto Alexithymia Scale). In the second phase of this study, some data concerning the childbirth course carried out from a “deliverygram” (such as labour, induction durations and modalities of delivery) and data relative to the newborns state of well-being (such as Apgar and pH indexes). Finally, in the third phase of the study women have been telephoned a month after the childbirth. The semistructured interview investigated the following areas: the memory concerning the delivery, the return to home, the first interactions between the mother and the newborn, the breastfeeding, the biological rhythms achieved from newborns. From the data analysis a sample with a good level of prenatal attachment and of support social and a good capability to mental functioning emerged. An interesting result is that the most of the women have a great percentage of “affectionless control style” with both parents, but data is not sufficient to interpret this result. Moreover, considering the data relative to the delivery, medical and welfare procedures, that have been necessary, are coherent with the Italian mean, while the percentage of the caesarean section (12.9%) is inferior to the national percentage (30%). The 29% of vaginal partum has got epidural analgesia, which explains the high number (37%) of obstetrician operations (such as Kristeller). The data relative to the newborn (22 male, 40 female) indicates a good state of well-being because Apgar and pH indexes are superior to 7 at first and fifth minutes. Concerning the prenatal phase, correlation analysis showed that: the prenatal attachment scores positively correlated with the expected social support and negatively correlated with the “externally oriented thinking” dimension of alexithymia; the maternity social support negatively correlated with total alexithymia score, particularly with the “externally oriented thinking” dimension, and negatively correlated with maternal control of parental bonding. Concerning the delivery data, there are many correlations (after all obvious) among themselves. The most important are that the labour duration negatively correlated with the newborn’s index state of well-being. Finally, concerning the data from the postpartum phase the women’ assessments relative to the partum negatively correlated with the duration of the delivery and positively correlated with the assessment relative to the return to home and the interaction with the newborn. Moreover the length of permanence in the hospital negatively correlated with women’s assessments relative to the return to home that, in turn, positively correlated with the quality of breastfeeding, the interaction between the mother and the newborn and the biological regulation of the child. Finally, the women’ assessments relative to breastfeeding positively correlated with the mother-child interactions and the biological rhythms of children. From the correlation analysis between the variables of the prenatal phase and the data relative to the delivery, emerged that the prenatal attachment scores positively correlated with the dilatation stage scores and with the newborn’s Apgar index at first minute, the paternal care dimension of parental bonding positively correlated with the lengths of the various periods of childbirth like so the paternal control dimension with placental stage. Moreover, emerged that the expected social support positively correlated with the lengths of the various periods of childbirth and that the global alexithymia scores, particularly “difficulty to describe emotions” dimension, negatively correlated with total childbirth scores. From the correlation analysis between the variables of the prenatal phase and variable of the postpartum phase emerged that the total alexithymia scores positively correlated with the time elapsed from the childbirth to the breastfeeding of the child, the difficulty to describe emotions dimension of the alexithymia negatively correlated with the quality of the breastfeeding, the “externally oriented thinking” dimension of the alexithymia negatively correlated with mother-child interactions, and finally the paternal control dimension of the parental bonding negatively correlated with the time elapsed from the child to the breastfeeding of the child. Finally, from the analysis of the correlation between the data of the partum and the women’s assessments of the postpartum phase, emerged the negative correlation between the woman’s assessment relative to the delivery and the quantitative of obstetrician operations and the lengths of the various periods of childbirth, the positive correlation between the women’s assessment about the length of delivery periods and the real lengths of the same ones, the positive relation between woman’s assessment relative to the delivery and the Apgar index of children. In conclusion, there is a remarkable relation between the quality of the relationship the woman establishes with the foetus that influences the course of the pregnancy and the delivery that, in turn, influences the postpartum outcome, particularly relative to the mother-children relationship. Such data should be confirmed by heterogeneous populations in order to identify vulnerable women and to project focused intervention.

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Hybrid vehicles represent the future for automakers, since they allow to improve the fuel economy and to reduce the pollutant emissions. A key component of the hybrid powertrain is the Energy Storage System, that determines the ability of the vehicle to store and reuse energy. Though electrified Energy Storage Systems (ESS), based on batteries and ultracapacitors, are a proven technology, Alternative Energy Storage Systems (AESS), based on mechanical, hydraulic and pneumatic devices, are gaining interest because they give the possibility of realizing low-cost mild-hybrid vehicles. Currently, most literature of design methodologies focuses on electric ESS, which are not suitable for AESS design. In this contest, The Ohio State University has developed an Alternative Energy Storage System design methodology. This work focuses on the development of driving cycle analysis methodology that is a key component of Alternative Energy Storage System design procedure. The proposed methodology is based on a statistical approach to analyzing driving schedules that represent the vehicle typical use. Driving data are broken up into power events sequence, namely traction and braking events, and for each of them, energy-related and dynamic metrics are calculated. By means of a clustering process and statistical synthesis methods, statistically-relevant metrics are determined. These metrics define cycle representative braking events. By using these events as inputs for the Alternative Energy Storage System design methodology, different system designs are obtained. Each of them is characterized by attributes, namely system volume and weight. In the last part the work, the designs are evaluated in simulation by introducing and calculating a metric related to the energy conversion efficiency. Finally, the designs are compared accounting for attributes and efficiency values. In order to automate the driving data extraction and synthesis process, a specific script Matlab based has been developed. Results show that the driving cycle analysis methodology, based on the statistical approach, allows to extract and synthesize cycle representative data. The designs based on cycle statistically-relevant metrics are properly sized and have satisfying efficiency values with respect to the expectations. An exception is the design based on the cycle worst-case scenario, corresponding to same approach adopted by the conventional electric ESS design methodologies. In this case, a heavy system with poor efficiency is produced. The proposed new methodology seems to be a valid and consistent support for Alternative Energy Storage System design.

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In this thesis, we present our work about some generalisations of ideas, techniques and physical interpretations typical for integrable models to one of the most outstanding advances in theoretical physics of nowadays: the AdS/CFT correspondences. We have undertaken the problem of testing this conjectured duality under various points of view, but with a clear starting point - the integrability - and with a clear ambitious task in mind: to study the finite-size effects in the energy spectrum of certain string solutions on a side and in the anomalous dimensions of the gauge theory on the other. Of course, the final desire woul be the exact comparison between these two faces of the gauge/string duality. In few words, the original part of this work consists in application of well known integrability technologies, in large parte borrowed by the study of relativistic (1+1)-dimensional integrable quantum field theories, to the highly non-relativisic and much complicated case of the thoeries involved in the recent conjectures of AdS5/CFT4 and AdS4/CFT3 corrspondences. In details, exploiting the spin chain nature of the dilatation operator of N = 4 Super-Yang-Mills theory, we concentrated our attention on one of the most important sector, namely the SL(2) sector - which is also very intersting for the QCD understanding - by formulating a new type of nonlinear integral equation (NLIE) based on a previously guessed asymptotic Bethe Ansatz. The solutions of this Bethe Ansatz are characterised by the length L of the correspondent spin chain and by the number s of its excitations. A NLIE allows one, at least in principle, to make analytical and numerical calculations for arbitrary values of these parameters. The results have been rather exciting. In the important regime of high Lorentz spin, the NLIE clarifies how it reduces to a linear integral equations which governs the subleading order in s, o(s0). This also holds in the regime with L ! 1, L/ ln s finite (long operators case). This region of parameters has been particularly investigated in literature especially because of an intriguing limit into the O(6) sigma model defined on the string side. One of the most powerful methods to keep under control the finite-size spectrum of an integrable relativistic theory is the so called thermodynamic Bethe Ansatz (TBA). We proposed a highly non-trivial generalisation of this technique to the non-relativistic case of AdS5/CFT4 and made the first steps in order to determine its full spectrum - of energies for the AdS side, of anomalous dimensions for the CFT one - at any values of the coupling constant and of the size. At the leading order in the size parameter, the calculation of the finite-size corrections is much simpler and does not necessitate the TBA. It consists in deriving for a nonrelativistc case a method, invented for the first time by L¨uscher to compute the finite-size effects on the mass spectrum of relativisic theories. So, we have formulated a new version of this approach to adapt it to the case of recently found classical string solutions on AdS4 × CP3, inside the new conjecture of an AdS4/CFT3 correspondence. Our results in part confirm the string and algebraic curve calculations, in part are completely new and then could be better understood by the rapidly evolving developments of this extremely exciting research field.

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Diese Doktorarbeit untersucht das Verhalten von komplexenFluidenunter Scherung, insbesondere den Einfluss von Scherflüssenauf dieStrukturbildung.Dazu wird ein Modell dieser entworfen, welches imRahmen von Molekulardynamiksimulationen verwendet wird.Zunächst werden Gleichgewichtseigenschaften dieses Modellsuntersucht.Hierbei wird unter anderem die Lage desOrdnungs--Unordnungsübergangs von derisotropen zur lamellaren Phase der Dimere bestimmt.Der Einfluss von Scherflüssen auf diese lamellare Phase wirdnununtersucht und mit analytischen Theorien verglichen. Die Scherung einer parallelen lamellaren Phase ruft eineNeuausrichtung des Direktors in Flussrichtung hervor.Das verursacht eine Verminderung der Schichtdicke mitsteigender Scherrateund führt oberhalb eines Schwellwertes zu Ondulationen.Ein vergleichbares Verhalten wird auch in lamellarenSystemengefunden, an denen in Richtung des Direktors gezogen wird.Allerdings wird festgestellt, dass die Art der Bifurkationenin beidenFällen unterschiedlich ist.Unter Scherung wird ein Übergang von Lamellen parallelerAusrichtung zu senkrechter gefunden.Dabei wird beoachtet, dass die Scherspannung in senkrechterOrientierungniedriger als in der parallelen ist.Dies führt unter bestimmten Bedingungen zum Auftreten vonScherbändern, was auch in Simulationen beobachtet wird. Es ist gelungen mit einem einfachen Modell viele Apsekte desVerhalten vonkomplexen Fluiden wiederzugeben. Die Strukturbildung hängt offensichtlich nurbedingt von lokalen Eigenschaften der Moleküle ab.

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The main objective of this work was to investigate the impact of different hybridization concepts and levels of hybridization on fuel economy of a standard road vehicle where both conventional and non-conventional hybrid architectures are treated exactly in the same way from the point of view of overall energy flow optimization. Hybrid component models were developed and presented in detail as well as the simulations results mainly for NEDC cycle. The analysis was performed on four different parallel hybrid powertrain concepts: Hybrid Electric Vehicle (HEV), High Speed Flywheel Hybrid Vehicle (HSF-HV), Hydraulic Hybrid Vehicle (HHV) and Pneumatic Hybrid Vehicle (PHV). In order to perform equitable analysis of different hybrid systems, comparison was performed also on the basis of the same usable system energy storage capacity (i.e. 625kJ for HEV, HSF and the HHV) but in the case of pneumatic hybrid systems maximal storage capacity was limited by the size of the systems in order to comply with the packaging requirements of the vehicle. The simulations were performed within the IAV Gmbh - VeLoDyn software simulator based on Matlab / Simulink software package. Advanced cycle independent control strategy (ECMS) was implemented into the hybrid supervisory control unit in order to solve power management problem for all hybrid powertrain solutions. In order to maintain State of Charge within desired boundaries during different cycles and to facilitate easy implementation and recalibration of the control strategy for very different hybrid systems, Charge Sustaining Algorithm was added into the ECMS framework. Also, a Variable Shift Pattern VSP-ECMS algorithm was proposed as an extension of ECMS capabilities so as to include gear selection into the determination of minimal (energy) cost function of the hybrid system. Further, cycle-based energetic analysis was performed in all the simulated cases, and the results have been reported in the corresponding chapters.

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Das Auftreten von Psychostimulantien im Straßenverkehr und eine Beeinträchtigung der Fahrtüchtigkeit durch diese spielt in Deutschland zunehmend eine wichtige Rolle. Das Ziel der hier vorliegenden Arbeit war es retrospektiv die dokumentierten Ausfallserscheinungen von Personen unter Einfluss von Amphetaminderivaten anhand von ärztlichen Untersuchungsbögen, die bei polizeilich angeordneten Blutentnahmen ausgefüllt werden, des Zeitraums 2001 bis 2005 in Rheinland-Pfalz zu untersuchen. Aufgrund der hohen Fallzahlen konnten sehr strenge Auswahlkriterien angewandt werden, sodass lediglich reine Amphetaminderivat-Intoxikationen (Amphetamin, Methamphetamin, MDA, MDMA, MDE, MBDB) bei 923 Personen untersucht werden konnten. Es zeigten sich als verkehrsrelevante Beeinflussung die Erweiterung der Pupille mit einer geringeren Lichtreagibilität, eine Verlängerung des Drehnachnystagmus sowie eine Unsicherheit beim Rombergtest. Eine Dosis-Wirkungs-Beziehung konnte lediglich bei der Pupillenweite ansatzweise gefunden werden. Bei MDMA zeigte sich ein deutlich stärkerer Einfluss auf die Pupillenweitenregulation als bei Amphetamin. Die zur Detektion von alkoholbedingten Ausfallserscheinungen sinnvollen Gleichgewichts- und Koordinationstests waren im Falle der hier betrachteten Psychstimulantien nicht aussagekräftig. Es erscheint empfehlenswert die durchgeführten Untersuchungen mit Hilfe von einheitlichen Lichtverhältnissen und festgelegten Untersuchungsprozedere zu standardisieren ggf. auch durch die Einführung der Videookulographie. Die Einführung eines Reaktionstests sollte in Erwägung gezogen werden.