931 resultados para comparative analysis
A Comparative Analysis between Ultrasonometry and Computer-Aided Tomography to Evaluate Bone Healing
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An ultrasonometric and computed-tomographic study of bone healing was undertaken using a model of a transverse mid-shaft osteotomy of sheep tibiae fixed with a semi-flexible external fixator. Fourteen sheep were operated and divided into two groups of seven according to osteotomy type, either regular or by segmental resection. The animals were killed on the 90th postoperative day and the tibiae resected for the in vitro direct contact transverse and axial measurement of ultrasound propagation velocity (UV) followed by quantitative computer-aided tomography (callus density and volume) through the osteotomy site. The intact left tibiae were used for control, being examined in a symmetrical diaphyseal segment. Regular osteotomies healed with a smaller and more mature callus than resection osteotomies. Axial UV was consistently and significantly higher (p?=?0.01) than transverse UV and both transverse and axial UV were significantly higher for the regular than for the segmental resection osteotomy. Transverse UV did not differ significantly between the intact and operated tibiae (p?=?0.20 for regular osteotomy; p?=?0.02 for resection osteotomy), but axial UV was significantly higher for the intact tibiae. Tomographic callus density was significantly higher for the regular than for the resection osteotomy and higher than both for the intact tibiae, presenting a strong positive correlation with UV. Callus volume presented an opposite behavior, with a negative correlation with UV. We conclude that UV is at least as precise as quantitative tomography for providing information about the healing state of both regular and resection osteotomy. (C) 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:10761082, 2012
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Biasi C., Borelli V., Benedicto H.G., Pereira M.R., Favaron P.O. & Bombonato P.P. 2012. [Comparative analysis between ventricular and sinoatrial node vascularization in cats.] Analise comparativa entre a vascularizacao ventricular e do no sinoatrial em gatos. Pesquisa Veterinaria Brasileira 31(1): 78-82. Setor de Anatomia dos Animais Domesticos e Silvestres, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitaria, Sao Paulo, SP 05508-000, Brazil. E-mail: caiobiasi@usp.br The possible existence of interdependence in the blood nutrition of both atrial and ventricular territories has been a subject of concern to cardiologists, mainly related to vascularization of the sinoatrial node and its dependence on just one coronary artery or both, and its relation with the predominance of these vessels in the ventricular vascularization. Therefore, this research aimed evaluated the relation of blood irrigation of the sinoatrial node in relation to the coronary artery predominance in the ventricle vascularization. In doing so, we analyzed 30 hearts of cats without pedigree, males and females, adults of several ages. They were not carrying any heart problems. The hearts were injected by the thoracic aorta with Neoprene Latex 450, stained with red pigment, and then they were dissected. It was found that when there was a prevalence of ventricular vascularization of the left type (63.34%) the sinoatrial node irrigation was predominantly in the dependency of the Ramus proximalis atrii dextri (78.9%) or with less frequency by Ramus proximalis atrii sinister (21.1%). In the ventricular vascularization of the balanced type (33.34%), the pacemaker irrigation was in dependence more often of Ramus proximalis atrii dextri (80%) or with less frequency the nutrition of the sinoatrial node occurred by Ramus proximalis atril sinister (20%). In a single-case, we observed the ventricular vascularization of the right type (3.34%), the pacemaker nutrition was in an exclusive dependence of the Ramus intermedius atril dextri. These results suggest in this species there is no relationship between both the sinoatrial node irrigation and the type of ventricular vascularization, regardless of gender.
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This study reports the isolation and biochemical characterization of two different serine proteases from Bothrops pirajai snake venom, thus providing a comparative analysis of the enzymes. The isolation process consisted of three consecutive chromatographic steps (Sephacryl S-200, Benzamidine Sepharose and C2/C18), resulting in two serine proteases, named BpirSP27 and BpirSP41 after their molecular masses by mass spectrometry (27,121 and 40,639 Da, respectively). Estimation by SDS-PAGE under denaturing conditions showed that, when deglycosylated with PNGase F, BpirSP27 and BpirSP41 had their molecular masses reduced by approximately 15 and 42%, respectively. Both are acidic enzymes, with pI of approximately 4.7 for BpirSP27 and 3.7 for BpirSP41, and their N-terminal amino acid sequences showed 57% identity to each other, with high similarity to the sequences of other snake venom serine proteases (SVSPs). The enzymes showed different actions on bovine fibrinogen, with BpirSP27 acting preferentially on the B beta chain and BpirSP41 on both A alpha and B beta chains. The two serine proteases were also able to degrade fibrin and blood clots in vitro depending on the doses and incubation periods, with higher results for BpirSP41. Both enzymes coagulated the human plasma in a dose-dependent manner, and BpirSP41 showed a higher coagulant potential, with minimum coagulant dose (MCD) of similar to 3.5 mu g versus 20 mu g for BpirSP27. The enzymes were capable of hydrolyzing different chromogenic substrates, including S-2238 for thrombin-like enzymes, but only BpirSP27 acted on the substrate S-2251 for plasmin. They also showed high stability against variations of temperature and pH, but their activities were significantly reduced after preincubation with Cu2+ ion and specific serine protease inhibitors. In addition. BpirSP27 induced aggregation of washed platelets to a greater extent than BpirSP41. The results showed significant structural and functional differences between B. pirajai serine proteases, providing interesting insights into the structure-function relationship of SVSPs. (C) 2012 Elsevier Masson SAS. All rights reserved.
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Introduction: The aim of this study was to compare Enterococcus faecalis biofilm formation on different substrates. Methods: Cell culture plates containing growth medium and E. faecalis (ATCC 29212) were used to grow biofilm on bovine dentin, gutta-percha, hydroxyapatite, or bovine bone. Substrates were incubated at 37 C for 14 or 21 days, and the medium was changed every 48 hours. After the growth induction periods, specimens (n = 5 per group and per induction period) were stained by using Live/Dead, and the images were analyzed under a confocal microscope. The total biovolume (mm3), live bacteria biovolume (mm3), and substrate coverage (%) were quantified by using the BioImage_L software. Results obtained were analyzed by nonparametric tests (P = .05). Results: Biofilm formation was observed in all groups. Gutta-percha had the lowest total biovolume at 14 days (P < .05) and hydroxyapatite the highest at 21 days (P < .05). No significant difference was observed in green biovolume at 14 days. At 21 days, however, hydroxyapatite had the highest volume (P < .05). The percentages of coverage were similar among all substrates at 21 days (P > .05), but at 14 days, bovine bone presented the highest coverage (P < .05). Conclusions: E. faecalis was capable of forming biofilm on all substrates during both growth periods; hydroxyapatite presented the highest rates of biofilm formation. The type of substrate influenced the biofilm characteristics, according to the parameters evaluated
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Objective: This study evaluated the variations in the anterior cranial base (S-N), posterior cranial base (S-Ba) and deflection of the cranial base (SNBa) among three different facial patterns (Pattern I, II and III). Method: A sample of 60 lateral cephalometric radiographs of Brazilian Caucasian patients, both genders, between 8 and 17 years of age was selected. The sample was divided into 3 groups (Pattern I, II and III) of 20 individuals each. The inclusion criteria for each group were the ANB angle, Wits appraisal and the facial profile angle (G’.Sn.Pg’). To compare the mean values obtained from (SNBa, S-N, S-Ba) each group measures, the ANOVA test and Scheffé’s Post-Hoc test were applied. Results and Conclusions: There was no statistically significant difference for the deflection angle of the cranial base among the different facial patterns (Patterns I, II and III). There was no significant difference for the measures of the anterior and posterior cranial base between the facial Patterns I and II. The mean values for S-Ba were lower in facial Pattern III with statistically significant difference. The mean values of S-N in the facial Pattern III were also reduced, but without showing statistically significant difference. This trend of lower values in the cranial base measurements would explain the maxillary deficiency and/or mandibular prognathism features that characterize the facial Pattern III.
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Different species of Laurencia have proven to be a rich source of natural products yielding interesting bioactive halogenated secondary metabolites, such as terpenoids and acetogenins. It is shown that such compounds are accumulated in the spherical, reniform to claviform refractive inclusions called corps en cerise (CC), which are intensively osmiophilic and located mainly in the cortical cells of the thalli and also in trichoblast cells. Up to now, it was believed that CC were present only in these two kinds of cells. Recently, however, a species of Laurencia, L. marilzae, with CC in all cells of the thallus, i.e., cortical, medullary, including the pericentral and axial cells, as well as in the trichoblasts, was described from the Canary Islands, and subsequently also reported to Brazil and Mexico. Within the Laurencia complex, only Laurencia species produce CC. Since the species of Laurencia are targets of interest for the prospection of bioactive substances due to their potential antibacterial, antifungal, anticholinesterasic, antileishmanial, cytotoxic, and antioxidant activities, the present paper carries out a comparative analysis of the corps en cerise in several species of Laurencia from the Atlantic Ocean to obtain basic information that can support natural product bioprospection projects. Our results show that the number and size of the CC are constant within a species, independent of the geographical distribution, corroborating their use for taxonomical purposes to differentiate groups of species that present a lower number from those that have a higher number. In this regard, there was a tendency for the number of CC to be higher in some species of Laurencia from the Canary Islands. The presence of CC can also be used to distinguish species in which these organelles are present in all cells of the thallus from those in which CC are restricted to the cortical cells. Among the species analyzed, L. viridis displayed the most varied secondary metabolites composition, such as sesquiterpenes, diterpenes, triterpenes, all of which showed potent antiviral, cytotoxic, and antitumoral activities, including protein phosphatase type 2A (PP2A) inhibitory effects.
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OBJECTIVE: To analyze the costs of human immunodeficiency virus (HIV) outpatient treatment for individuals with different CD4 cell counts in the Brazilian public health system, and to compare to costs in other national health systems. METHODS: A retrospective survey was conducted in five public outpatient clinics of the Brazilian national HIV program in the city of São Paulo. Data on healthcare services provided for a period of one year of HIV outpatient treatment were gathered from randomly selected medical records. Prices of inputs used were obtained through market research and public sector databases. Information on costs of HIV outpatient treatment in other national health systems were gathered from the literature. Annual costs of HIV outpatient treatment from each country were converted into 2010 U.S. dollars. RESULTS: Annual cost of HIV outpatient treatment for the Brazilian national public program was US$ 2,572.92 in 2006 in São Paulo, ranging from US$ 1,726.19 for patients with CD4 cell count > 500 to US$ 3,693.28 for patients with 51 < CD4 cell count < 200. Antiretrovirals (ARVs) represented approximately 62.0% of annual HIV outpatient costs. Comparing among different health systems during the same period, HIV outpatient treatment presented higher costs in countries where HIV treatment is provided by the private sector. CONCLUSION: The main cost drivers of HIV outpatient treatment in different health systems were: ARVs, other medications, health professional services, and diagnostic exams. Nevertheless, the magnitude of cost drivers varied among HIV outpatient treatment programs due to health system efficiency. The data presented may be a valuable tool for public policy evaluation of HIV treatment programs worldwide.
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OBJECTIVE: To assess the results of palmar and axillary hyperhidrosis treatment in males and females using low doses of oxybutynin. METHODS: A retrospective analysis was conducted in 395 women and 170 men followed up in our service with complaint of palmar and axillary hyperhidrosis. RESULTS: A total of 70% of patients in both groups presented partial or great improvement in the level of hyperhidrosis after treatment. The best results were obtained in the female group, in which 40% classified their improvement as "great". Approximately 70% of the patients in both groups improved their quality of life after medical therapy and 30% presented no change in condition. CONCLUSION: Gender is not a factor that significantly interferes in oxybutynin treatment results. Quality of life indices and clinical improvement level were similar in men and women.
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The present study aimed to comparatively verify the relation between the hermit crabs and the shells they use in two populations of Loxopagurus loxochelis. Samples were collected monthly from July 2002 to June 2003, at Caraguatatuba and Ubatuba Bay, São Paulo, Brazil. The animals sampled had their sex identified, were weighed and measured; their shells were identified, measured and weighed, and their internal volume determined. To relate the hermit crab's characteristics and the shells' variables, principal component analysis (PCA) and a regression tree were used. According to the PCA analysis, the three gastropod shells most frequently used by L. loxochelis varied in size. The regression tree successfully explained the relationship between the hermit crab's characteristics and the internal volume of the inhabited shell. It can be inferred that the relationship between the morphometry of an individual hermit crab and its shell is not straightforward and it is impossible to explain only on the basis of direct correlations between the body's and the shell's attributes. Several factors (such as the morphometry and the availability of the shell, environmental conditions and inter- and intraspecific competition) interact and seem to be taken into consideration by the hermit crabs when they choose a shell, resulting in the diversified pattern of shell occupancy shown here and elsewhere.
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Ticks are classified into three families: Argasidae, Ixodidae, and Nutalliellidae. The taxonomy and phylogeny within Ixodidae are still discussed by the specialists, thus requiring further studies. Amblyomma cajennese and Amblyomma aureolatum (Brazil) belong to two species complexes known as “cajennese” and “ovale”, respectively, and are directly related to the transmission of the Brazilian spotted fever. This confirms the medical and veterinary significance of these species, as well as the need for further morphological studies that will bring a better understanding of their taxonomy, phylogeny, and control. In this context, the present study aimed to characterize the morphology of the male reproductive system of A. cajennese and A. aureolatum when unfed and after 4 days of feeding, thereby seeking to: (a) distinguish the two species or “complexes”, and (b) study an internal system which has the potential to be targeted by acaricides. Therefore, males from both species (unfed and after 4 days of feeding) were cold-anesthetized, dissected, and had their reproductive systems removed for histological analysis. The results showed that the morphology of the male reproductive system is generally similar between both species, like in other Ixodidae ticks, exhibiting a multilobed accessory gland complex related to seminal fluid secretion, a pair of vasa deferentia and a pair of testes housing germ cells (spermatocytes) in different stages. The main differences were found in the development of the accessory gland complex cells and germ cells, showing that the maturation of the male reproductive system starts later in A. aureolatum, when compared to A. cajennese. However, during the blood meal, A. aureolatum development is increased, thus making germ cell maturation and gland complex activity higher than in A. cajennese. This study shows the differences in the development of the male reproductive systems of both species, while providing information that can assist in the establishment of new control methods.
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Dengue is considered one of the most important vector-borne infection, affecting almost half of the world population with 50 to 100 million cases every year. In this paper, we present one of the simplest models that can encapsulate all the important variables related to vector control of dengue fever. The model considers the human population, the adult mosquito population and the population of immature stages, which includes eggs, larvae and pupae. The model also considers the vertical transmission of dengue in the mosquitoes and the seasonal variation in the mosquito population. From this basic model describing the dynamics of dengue infection, we deduce thresholds for avoiding the introduction of the disease and for the elimination of the disease. In particular, we deduce a Basic Reproduction Number for dengue that includes parameters related to the immature stages of the mosquito. By neglecting seasonal variation, we calculate the equilibrium values of the model’s variables. We also present a sensitivity analysis of the impact of four vector-control strategies on the Basic Reproduction Number, on the Force of Infection and on the human prevalence of dengue. Each of the strategies was studied separately from the others. The analysis presented allows us to conclude that of the available vector control strategies, adulticide application is the most effective, followed by the reduction of the exposure to mosquito bites, locating and destroying breeding places and, finally, larvicides. Current vector-control methods are concentrated on mechanical destruction of mosquitoes’ breeding places. Our results suggest that reducing the contact between vector and hosts (biting rates) is as efficient as the logistically difficult but very efficient adult mosquito’s control.
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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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Modern food systems are characterized by a high energy intensity as well as by the production of large amounts of waste, residuals and food losses. This inefficiency presents major consequences, in terms of GHG emissions, waste disposal, and natural resource depletion. The research hypothesis is that residual biomass material could contribute to the energetic needs of food systems, if recovered as an integrated renewable energy source (RES), leading to a sensitive reduction of the impacts of food systems, primarily in terms of fossil fuel consumption and GHG emissions. In order to assess these effects, a comparative life cycle assessment (LCA) has been conducted to compare two different food systems: a fossil fuel-based system and an integrated system with the use of residual as RES for self-consumption. The food product under analysis has been the peach nectar, from cultivation to end-of-life. The aim of this LCA is twofold. On one hand, it allows an evaluation of the energy inefficiencies related to agro-food waste. On the other hand, it illustrates how the integration of bioenergy into food systems could effectively contribute to reduce this inefficiency. Data about inputs and waste generated has been collected mainly through literature review and databases. Energy balance, GHG emissions (Global Warming Potential) and waste generation have been analyzed in order to identify the relative requirements and contribution of the different segments. An evaluation of the energy “loss” through the different categories of waste allowed to provide details about the consequences associated with its management and/or disposal. Results should provide an insight of the impacts associated with inefficiencies within food systems. The comparison provides a measure of the potential reuse of wasted biomass and the amount of energy recoverable, that could represent a first step for the formulation of specific policies on the integration of bioenergies for self-consumption.
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Die Neurogenese und axonale Wegfindung sind in den vergangenen Jahrzehnten Thema einer Vielzahl wissenschaftlicher Untersuchungen in den verschiedensten Organismen gewesen. Die zusammengetragenen Daten in Insekten und Crustaceen geben eine gute Übersicht darüber, wie das Nervensystem in Arthropoden aufgebaut wird. Die entwicklungsbiologischen Prozesse, die daran beteiligt sind, sind in den beiden genannten Gruppen sehr gut verstanden. In den Gruppen der Cheliceraten und Myriapoden jedoch wurden ähnliche Analysen bisher kaum durchgeführt. Das Hauptanliegen dieser Arbeit war es daher, Mechanismen in den Spinnen Achaearanea tepidariorum und Cupiennius salei, zwei Vertretern der Cheliceraten, zu untersuchen, die eine Rolle im Leitsystem der ventralen Mittellinie und bei der axonalen Wegfindung spielen. Eine Vorraussetzung hierfür sind Kenntnisse über die Architektur des Zentralnervensystems. In einem ersten Schritt beschrieb ich daher grundlegend die Morphologie des Nervensystems im Verlauf der gesamten Embryoalentwicklung. Ich konnte zeigen, dass in Spinnen ein für Arthropoden typisches Strickleiternervensystem gebildet wird. Dieses wird von segmental angelegten Neuronen geformt, wobei sowohl Gruppen von Zellen als auch einzelne Neurone daran beteiligt sind, die primären axonalen Trakte zu etablieren. Im Besonderen konnte ich eine Zelle identifizieren, die in Position, Projektionsmuster und der Expression des Markergens even-skipped vergleichbar zum PR2 Neuron in Drosophila ist, welches die posteriore Wurzel des Segmentalnervs anlegt.rnrnIn einem zweiten Ansatz untersuchte ich die ventrale Mittellinie in Spinnen im Bezug auf ihre mögliche Funktion in der axonalen Wegfindung. Es konnte gezeigt werden, dass es sich beim Epithel der Mittellinie, das die Lücke zwischen beiden Keimstreifhälften während des gesamten Prozesses der Inversion überspannt, um eine transiente Struktur handelt, die keine neuralen Zellen hervorbringt. Es ist daher vergleichbar mit der so genannten Floor plate in Vertebraten, die ebenfalls nur vorübergehend existiert. Die Untersuchung von single minded (sim) zeigte, dass es, anders als in Drosophila, wo sim ein wichtiges regulatorisches Gen für die korrekte Spezifizierung von Mittellinienzellen ist, nicht in den Zellen der Mittellinie, sondern in diesen benachbarten Zellen, exprimiert wird. Das ist vergleichbar mit Vertebraten. Zusätzlich konnte ich Expression von sim an den Basen der Gliedmassen und im Kopf nachweisen. Wie in Vertebraten könnte sim an der Musterbildung dieser Gewebe beteiligt sein. Dennoch spielt die Mittellinie in Spinnen eine wichtige Rolle als Organisator für auswachsende, kommissurale Axone. Diese Funktion teilt sie mit anderen Invertebraten und Vertebraten.rnrnDie Signaltransduktionskaskade, die an der axonalen Wegfindung an der Mittellinie beteiligt ist, ist in den verschiedensten Organismen hoch konserviert. In der vorliegenden Arbeit konnte ich sowohl in Achaearanea als auch in Cupiennius ein netrin Homolog identifizieren und eine konservierte Funktion des Wegfindungsmoleküls während der Bildung der Kommissuren aufzeigen. RNAi Experimente belegen, dass, wird die Funktion von netrin herunterreguliert, das Strickleiternervensystem nicht korrekt gebildet wird, ins Besondere die kommissuralen Faszikel. Des Weiteren konnte ich eine neue Funktion von netrin, die bisher in anderen Organsimen noch nicht beschrieben wurde, identifizieren. Neben seiner Rolle in der axonalen Wegfindung, scheint netrin auch an der epithelialen Morphogenese im zentralen Nervensystem beteiligt zu sein. In dieser Funktion scheint netrin in Gliazellen, die die epithelialen Vesikel der Invaginationsgruppen umhüllen, wichtig zu sein, um neurale Vorläuferzellen in einem undifferenzierten Zustand zu halten. Der Abbau von netrin Transkript durch RNA Interferenz führt zu einer verfrühten Segregation neuraler Vorläuferzellen aus dem epithelialen Verband der Invaginationsgruppen und zu einer Zunahme an Zellen, die den frühen Differenzierungsmarker islet exprimieren.
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The inter-American human rights system has been conceived following the example of the European system under the European Convention on Human Rights (ECHR) before it was modified by Protocol No 11. However, two important differences exist. First, the authority of the European Court of Human Rights (ECtHR) to order reparation has been strictly limited by the principle of subsidiarity. Thus, the ECtHR's main function is to determine whether the ECHR has been violated. Beyond the declaratory effect of its judgments, according to Article 41 ECHR, it may only "afford just satisfaction to the injured party". The powers of the Inter-American Court of Human Rights (IACtHR) were conceived in a much broader fashion in Article 63 of the American Convention on Human Rights (ACHR), giving the Court the authority to order a variety of individual and general measures aimed at obtaining restitutio in integrum. The first main part of this thesis shows how both Courts have developed their reparation practice and examines the advantages and disadvantages of each approach. Secondly, the ECtHR's rather limited reparation powers have, interestingly, been combined with an elaborate implementation system that includes several of the Council of Europe's organs, principally the Committee of Ministers. In the Inter-American System, no dedicated mechanism was implemented to oversee compliance with the IACtHR's judgments. The ACHR limits itself to inviting the Court to point out in its annual reports the cases that have not been complied with and to propose measures to be adopted by the General Assembly of the Organization of American States. The General Assembly, however, hardly ever took action. The IACtHR has therefore filled this gap by developing a proper procedure to oversee compliance with its judgments. Both the European and the American solutions to ensure compliance are presented and compared in the second main part of this thesis. Finally, based on the results of both main parts, a comparative analysis of the reparation practice and the execution results in both human rights systems is being provided, aimed at developing proposals for the improvement of the functioning of either human rights protection system.