924 resultados para Freedom to offend


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We consider the Schrödinger equation for a relativistic point particle in an external one-dimensional δ-function potential. Using dimensional regularization, we investigate both bound and scattering states, and we obtain results that are consistent with the abstract mathematical theory of self-adjoint extensions of the pseudodifferential operator H=p2+m2−−−−−−−√. Interestingly, this relatively simple system is asymptotically free. In the massless limit, it undergoes dimensional transmutation and it possesses an infrared conformal fixed point. Thus it can be used to illustrate nontrivial concepts of quantum field theory in the simpler framework of relativistic quantum mechanics.

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PURPOSE The range of patient setup errors in six dimensions detected in clinical routine for cranial as well as for extracranial treatments, were analyzed while performing linear accelerator based stereotactic treatments with frameless patient setup systems. Additionally, the need for re-verification of the patient setup for situations where couch rotations are involved was analyzed for patients treated in the cranial region. METHODS AND MATERIALS A total of 2185 initial (i.e. after pre-positioning the patient with the infrared system but before image guidance) patient setup errors (1705 in the cranial and 480 in the extracranial region) obtained by using ExacTrac (BrainLAB AG, Feldkirchen, Germany) were analyzed. Additionally, the patient setup errors as a function of the couch rotation angle were obtained by analyzing 242 setup errors in the cranial region. Before the couch was rotated, the patient setup error was corrected at couch rotation angle 0° with the aid of image guidance and the six degrees of freedom (6DoF) couch. For both situations attainment rates for two different tolerances (tolerance A: ± 0.5mm, ± 0.5°; tolerance B: ± 1.0 mm, ± 1.0°) were calculated. RESULTS The mean (± one standard deviation) initial patient setup errors for the cranial cases were -0.24 ± 1.21°, -0.23 ± 0.91° and -0.03 ± 1.07° for the pitch, roll and couch rotation axes and 0.10 ± 1.17 mm, 0.10 ± 1.62 mm and 0.11 ± 1.29 mm for the lateral, longitudinal and vertical axes, respectively. Attainment rate (all six axes simultaneously) for tolerance A was 0.6% and 13.1% for tolerance B, respectively. For the extracranial cases the corresponding values were -0.21 ± 0.95°, -0.05 ± 1.08° and -0.14 ± 1.02° for the pitch, roll and couch rotation axes and 0.15 ± 1.77 mm, 0.62 ± 1.94 mm and -0.40 ± 2.15 mm for the lateral, longitudinal and vertical axes. Attainment rate (all six axes simultaneously) for tolerance A was 0.0% and 3.1% for tolerance B, respectively. After initial setup correction and rotation of the couch to treatment position a re-correction has to be performed in 77.4% of all cases to fulfill tolerance A and in 15.6% of all cases to fulfill tolerance B. CONCLUSION The analysis of the data shows that all six axes of a 6DoF couch are used extensively for patient setup in clinical routine. In order to fulfill high patient setup accuracies (e.g. for stereotactic treatments), a 6DoF couch is recommended. Moreover, re-verification of the patient setup after rotating the couch is required in clinical routine.

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BACKGROUND Rapid pulmonary vein (PV) activity has been shown to maintain paroxysmal atrial fibrillation (AF). We evaluated in persistent AF the cycle length (CL) gradient between PVs and the left atrium (LA) in an attempt to identify the subset of patients where PVs play an important role. METHODS AND RESULTS Ninety-seven consecutive patients undergoing first ablation for persistent AF were studied. For each PV, the CL of the fastest activation was assessed over 1 minute (PVfast) using Lasso recordings. The PV to LA CL gradient was quantified by the ratio of PVfast to LA appendage (LAA) AF CL. Stepwise ablation terminated AF in 73 patients (75%). In the AF termination group, the PVfast CL was much shorter than the LAA CL resulting in lower PVfast/LAA ratios compared with the nontermination group (71±10% versus 92±7%; P<0.001). Within the termination group, PVfast/LAA ratios were notably lower if AF terminated after PV isolation or limited adjunctive substrate ablation compared with patients who required moderate or extensive ablation (63±6% versus 75±8%; P<0.001). PVfast/LAA ratio <69% predicted AF termination after PV isolation or limited substrate ablation with 74% positive predictive value and 95% negative predictive value. After a mean follow-up of 29±17 months, freedom from arrhythmia recurrence off-antiarrhythmic drugs was achieved in most patients with PVfast/LAA ratios <69% as opposed to the remaining population (80% versus 43%; P<0.001). CONCLUSIONS The PV to LA CL gradient may identify the subset of patients in whom persistent AF is likely to terminate after PV isolation or limited substrate ablation and better long-term outcomes are achieved.

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OBJECTIVES This study reports a series of pitfalls, premature failures and explantations of the third-generation Freedom SOLO (FS) bovine pericardial stentless valve. METHODS A total of 149 patients underwent aortic valve replacement using the FS. Follow-up was 100% complete with an average observation time of 5.5 ± 2.3 years (maximum 8.7 years) and a total of 825 patient-years. Following intraoperative documentation, all explanted valve prostheses underwent histological examination. RESULTS Freedom from structural valve deterioration (SVD) at 5, 6, 7, 8 and 9 years was 92, 88, 80, 70 and 62%, respectively. Fourteen prostheses required explantation due to valve-independent dysfunction (n = 5; i.e. thrombus formation, oversizing, aortic dilatation, endocarditis and suture dehiscence) or valve-dependent failure (acute leaflet tears, n = 4 and severe stenosis, n = 5). Thus, freedom from explantation at 5, 6, 7, 8 and 9 years was 95, 94, 91, 81 and 72%, respectively. An acute vertical tear along the non-coronary/right coronary commissure to the base occurred at a mean of 6.0 years (range 4.3-7.3 years) and affected size 25 and 27 prostheses exclusively. Four FS required explantation after a mean of 7.5 years (range 7.0-8.3 years) due to severe functional stenosis and gross calcification that included the entire aortic root. CONCLUSIONS The FS stentless valve is safe to implant and shows satisfying mid-term results in our single institution experience. Freedom from SVD and explantation decreased markedly after only 6-7 years, so that patients with FS require close observation and follow-up. Exact sizing, symmetric positioning and observing patient limitations are crucial for optimal outcome.

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Abstract: The third-generation bovine pericardium Freedom SOLO (FS) stentless valve emerged in 2004 as a modified version of the Pericarbon Freedom stentless valve and as a very attractive alternative to stented bioprostheses. The design, choice of tissue, and anticalcification treatment fulfill most, if not all, requirements for an ideal valve substitute. The FS combines the single-suture, subcoronary implantation technique with the latest-generation bovine pericardial tissue and novel anticalcification treatment. The design allows imitation of the native healthy valve through unrestricted adaption to the patient's anatomy, reproducing a normal valve/root complex. However, despite hemodynamic performance superior to stented valves, we are approaching a critical observation period as superior durability, freedom from structural valve deterioration, and nonstructural failure has not been proven as expected. However, optimal performance and freedom from structural valve deterioration depend on correct sizing and perfect symmetric implantation, to ensure low leaflet stress. Any malpositioning can lead to tissue fatigue over time. Furthermore, the potential for better outcomes depends on optimal patient selection and observance of the limitations for the use of stentless valves, particularly for the FS. Clearly, stentless valve implantation techniques are less reproducible and standardized, and require surgeon-dependent experience and skill. Regardless of whether or not stentless valve durability surpasses third-generation stented bioprostheses, they will continue to play a role in the surgical repertoire. This review intends to help practitioners avoid pitfalls, observe limitations, and improve patient selection for optimal long-term outcome with the attractive FS stentless valve.

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Abstract Objectives We report our institutional experience and long-term results with the Sorin Freedom SOLO bovine pericardial stentless bioprosthesis. Methods Between January 2005 and November 2009, 149 patients (mean age 73.6±8.7 years, 68 [45.6%] female) underwent isolated (n=75) or combined (n=74) aortic valve replacement (AVR) using the SOLO in our institution. Follow-up was 100% complete with an average follow-up time of 5.9±2.6 years (maximum 9.6 years) and a total of 885.3 patient years. Results Operative (30-day) mortality was 2.7% (1.3% for isolated AVR [n=1] and 4.0% for combined procedures [n=3]). All causes of death were not valve-related. Preoperative peak (mean) gradients of 74.2±23.0 mmHg (48.6 ± 16.3 mmHg) decreased to 15.6±5.4 (8.8±3.0) after AVR, and remained low for up to 9 years. The postoperative effective orifice area (EOA) was 1.6 ±0.57 cm2, 1.90±0.45 cm2, 2.12±0.48 cm2 and 2.20±0.66 cm2 for the valve sizes 21, 23, 25 and 27, respectively; with absence of severe prosthesis-patient-mismatch (PPM) and 0.7% (n=1) moderate PPM. During follow-up, Twenty-six patients experienced structural valve deterioration (SVD) and 14 patients underwent explantation. Kaplan-Meier estimates for freedom from death, explantation and SVD at 9 years averaged 0.57 [0.47‒0.66], 0.82 [0.69‒0.90] and 0.70 [0.57‒0.79], respectively. Conclusions The Freedom SOLO stentless aortic valve is safe to implant and shows excellent early and mid-term hemodynamic performance. However, SVD was observed in a substantial number of patients after only 5 ̶ 6 years and the need for explantation increased markedly, suggesting low durability.

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BACKGROUND The Sorin Freedom SOLO (FS) bovine pericardial stentless valve prosthesis is designed for supraannular, subcoronary implantation. We report our experience and results with 277 consecutively implanted FS bioprostheses. METHODS 277 patients (mean age, 74.2 ± 7.3 years; 139 (50.2%) female) underwent aortic valve replacement (AVR) with the FS stentless bioprosthesis. The hemodynamic performance was investigated with transthoracic echocardiography at discharge, 6 months later, and yearly thereafter. Follow-up was 100% complete, with an average observation time of 2.6 ± 1.7 years and a total of 697.3 patient-years. RESULTS The overall 30-day mortality was 4.3%. The mortalities for isolated AVR and combined procedures were 1.9% and 7.3%, respectively. No causes of death were valve-related. Preoperative peak (74.2 ± 23.0 mm Hg) and mean (48.6 ± 16.3 mm Hg) gradients decreased to 15.6 ± 5.4 mm Hg and 8.8 ± 3.0 mm Hg postoperatively and remained unchanged for as long as 5 years. The postoperative mean effective orifice area (EOA) for valve sizes 19, 21, 23, 25, and 27 were 1.49 ± 0.32 cm(2), 1.67 ± 0.40 cm(2), 1.92 ± 0.38 cm(2), 2.01 ± 0.42 cm(2), and 2.13 ± 0.36 cm(2), respectively. Severe prosthesis-patient mismach (PPM) was completely absent, and moderate PPM occurred in 17 patients (6.1%). In isolated AVR, 0.8% of patients with preoperative sinus rhythm required a permanent pacemaker before hospital discharge. There was 100% freedom from structural valve deterioration, 99.6 % freedom from endocarditis and reoperation, and 97.3% freedom from thromboembolism at 5 years. CONCLUSIONS The FS stentless aortic valve is safe to implant, and it shows excellent hemodynamic performance and early and midterm results. Owing to the favorable EOA, the valve appears particularly attractive for patients at risk for PPM.

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Bovine viral diarrhea- and Border disease viruses of sheep belong to the highly diverse genus pestivirus of the Flaviviridae. Ruminant pestiviruses may infect a wide range of domestic and wild cloven-hooved mammals (artiodactyla). Due to its economic importance, programs to eradicate bovine viral diarrhea are a high priority in the cattle industry. By contrast, Border disease is not a target of eradication, although the Border disease virus is known to be capable of also infecting cattle. In this work, we compared single dose experimental inoculation of calves with Border disease virus with co-mingling of calves with sheep persistently infected with this virus. As indicated by seroconversion, infection was achieved only in one out of seven calves with a dose of Border disease virus that was previously shown to be successful in calves inoculated with BVD virus. By contrast, all calves kept together with persistently infected sheep readily became infected with Border disease virus. The ease of viral transmission from sheep to cattle and the antigenic similarity of bovine and ovine pestiviruses may become a problem for demonstrating freedom of BVD by serology in the cattle population.

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We developed a model to calculate a quantitative risk score for individual aquaculture sites. The score indicates the risk of the site being infected with a specific fish pathogen (viral haemorrhagic septicaemia virus (VHSV); infectious haematopoietic necrosis virus, Koi herpes virus), and is intended to be used for risk ranking sites to support surveillance for demonstration of zone or member state freedom from these pathogens. The inputs to the model include a range of quantitative and qualitative estimates of risk factors organised into five risk themes (1) Live fish and egg movements; (2) Exposure via water; (3) On-site processing; (4) Short-distance mechanical transmission; (5) Distance-independent mechanical transmission. The calculated risk score for an individual aquaculture site is a value between zero and one and is intended to indicate the risk of a site relative to the risk of other sites (thereby allowing ranking). The model was applied to evaluate 76 rainbow trout farms in 3 countries (42 from England, 32 from Italy and 2 from Switzerland) with the aim to establish their risk of being infected with VHSV. Risk scores for farms in England and Italy showed great variation, clearly enabling ranking. Scores ranged from 0.002 to 0.254 (mean score 0.080) in England and 0.011 to 0.778 (mean of 0.130) for Italy, reflecting the diversity of infection status of farms in these countries. Requirements for broader application of the model are discussed. Cost efficient farm data collection is important to realise the benefits from a risk-based approach.

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Simulating surface wind over complex terrain is a challenge in regional climate modelling. Therefore, this study aims at identifying a set-up of the Weather Research and Forecasting Model (WRF) model that minimises system- atic errors of surface winds in hindcast simulations. Major factors of the model configuration are tested to find a suitable set-up: the horizontal resolution, the planetary boundary layer (PBL) parameterisation scheme and the way the WRF is nested to the driving data set. Hence, a number of sensitivity simulations at a spatial resolution of 2 km are carried out and compared to observations. Given the importance of wind storms, the analysis is based on case studies of 24 historical wind storms that caused great economic damage in Switzerland. Each of these events is downscaled using eight different model set-ups, but sharing the same driving data set. The results show that the lack of representation of the unresolved topography leads to a general overestimation of wind speed in WRF. However, this bias can be substantially reduced by using a PBL scheme that explicitly considers the effects of non-resolved topography, which also improves the spatial structure of wind speed over Switzerland. The wind direction, although generally well reproduced, is not very sensitive to the PBL scheme. Further sensitivity tests include four types of nesting methods: nesting only at the boundaries of the outermost domain, analysis nudging, spectral nudging, and the so-called re-forecast method, where the simulation is frequently restarted. These simulations show that restricting the freedom of the model to develop large-scale disturbances slightly increases the temporal agreement with the observations, at the same time that it further reduces the overestimation of wind speed, especially for maximum wind peaks. The model performance is also evaluated in the outermost domains, where the resolution is coarser. The results demonstrate the important role of horizontal resolution, where the step from 6 to 2 km significantly improves model performance. In summary, the combination of a grid size of 2 km, the non-local PBL scheme modified to explicitly account for non-resolved orography, as well as analysis or spectral nudging, is a superior combination when dynamical downscaling is aimed at reproducing real wind fields.

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Denosumab reduced the incidence of new fractures in postmenopausal women with osteoporosis by 68% at the spine and 40% at the hip over 36 months compared with placebo in the FREEDOM study. This efficacy was supported by improvements from baseline in vertebral (18.2%) strength in axial compression and femoral (8.6%) strength in sideways fall configuration at 36 months, estimated in Newtons by an established voxel-based finite element (FE) methodology. Since FE analyses rely on the choice of meshes, material properties, and boundary conditions, the aim of this study was to independently confirm and compare the effects of denosumab on vertebral and femoral strength during the FREEDOM trial using an alternative smooth FE methodology. Unlike the previous FE study, effects on femoral strength in physiological stance configuration were also examined. QCT data for the proximal femur and two lumbar vertebrae were analyzed by smooth FE methodology at baseline, 12, 24, and 36 months for 51 treated (denosumab) and 47 control (placebo) subjects. QCT images were segmented and converted into smooth FE models to compute bone strength. L1 and L2 vertebral bodies were virtually loaded in axial compression and the proximal femora in both fall and stance configurations. Denosumab increased vertebral body strength by 10.8%, 14.0%, and 17.4% from baseline at 12, 24, and 36 months, respectively (p < 0.0001). Denosumab also increased femoral strength in the fall configuration by 4.3%, 5.1%, and 7.2% from baseline at 12, 24, and 36 months, respectively (p < 0.0001). Similar improvements were observed in the stance configuration with increases of 4.2%, 5.2%, and 5.2% from baseline (p ≤ 0.0007). Differences between the increasing strengths with denosumab and the decreasing strengths with placebo were significant starting at 12 months (vertebral and femoral fall) or 24 months (femoral stance). Using an alternative smooth FE methodology, we confirmed the significant improvements in vertebral body and proximal femur strength previously observed with denosumab. Estimated increases in strength with denosumab and decreases with placebo were highly consistent between both FE techniques.

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Gebiet: Chirurgie Abstract: Objectives This study reports a series of pitfalls, premature failures and explantations of the third generation Freedom SOLO bovine pericardial stentless valve. – – Methods 149 patients underwent aortic valve replacement (AVR) using the FS. Follow-up was 100% complete with an average observation time of 5.5±2.3 years (max. 8.7 years) and a total of 825 patient years. Following intraoperative documentation, all explanted valve prostheses underwent histological examination. – – Results Freedom from structural valve deterioration (SVD) at 5, 6, 7, 8 and 9 years was 92%, 88%, 80% and 70% and 62%, respectively. 14 prostheses required explantation due to valve-independent dysfunction (n=5, i.e. thrombus formation, oversizing, aortic dilatation, endocarditis and suture dehiscence) or valve-dependent failure (acute leaflet tears, n=4, severe stenosis, n=5). Thus freedom from explantation at 5, 6, 7, 8 and 9 years was 95%, 94%, 91% and 81% and 72%, respectively. An acute vertical tear along the non-coronary/right-coronary commissure to the base occurred at a mean of 6.0 years [range 4.3?7.3 years] and affected size 25 and 27 prostheses exclusively. Four FS required explantation after a mean of 7.5 years [range 7.0?8.3 years] due to severe functional stenosis and gross calcification that included the entire aortic root. – – Conclusions The Freedom SOLO stentless valve is safe to implant and shows satisfying mid-term results in our single institution experience. Freedom from SVD and explantation decreased markedly after only 6 ? 7 years, so that patients with FS require close observation and follow-up. Exact sizing, symmetric positioning and observing patient limitations are crucial for optimal outcome.

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Limited data exist on the efficacy of long-term therapies for osteoporosis. In osteoporotic postmenopausal women receiving denosumab for 7 years, nonvertebral fracture rates significantly decreased in years 4-7 versus years 1-3. This is the first demonstration of a further benefit on fracture outcomes with long-term therapy for osteoporosis. INTRODUCTION This study aimed to evaluate whether denosumab treatment continued beyond 3 years is associated with a further reduction in nonvertebral fracture rates. METHODS Participants who completed the 3-year placebo-controlled Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months (FREEDOM) study were invited to participate in an open-label extension. The present analysis includes 4,074 postmenopausal women with osteoporosis (n = 2,343 long-term; n = 1,731 cross-over) who enrolled in the extension, missed ≤1 dose during their first 3 years of denosumab treatment, and continued into the fourth year of treatment. Comparison of nonvertebral fracture rates during years 1-3 of denosumab with that of the fourth year and with the rate during years 4-7 was evaluated. RESULTS For the combined group, the nonvertebral fracture rate per 100 participant-years was 2.15 for the first 3 years of denosumab treatment (referent) and 1.36 in the fourth year (rate ratio [RR] = 0.64; 95 % confidence interval (CI) = 0.48 to 0.85, p = 0.003). Comparable findings were observed in the groups separately and when nonvertebral fracture rates during years 1-3 were compared to years 4-7 in the long-term group (RR = 0.79; 95 % CI = 0.62 to 1.00, p = 0.046). Fracture rate reductions in year 4 were most prominent in subjects with persisting low hip bone mineral density (BMD). CONCLUSIONS Denosumab treatment beyond 3 years was associated with a further reduction in nonvertebral fracture rate that persisted through 7 years of continuous denosumab administration. The degree to which denosumab further reduces nonvertebral fracture risk appears influenced by the hip bone density achieved with initial therapy.

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UNLABELLED The FREEDOM study and its Extension provide long-term information about the effects of denosumab for the treatment of postmenopausal osteoporosis. Treatment for up to 8 years was associated with persistent reduction of bone turnover, continued increases in bone mineral density, low fracture incidence, and a favorable benefit/risk profile. INTRODUCTION This study aims to report the results through year 5 of the FREEDOM Extension study, representing up to 8 years of continued denosumab treatment in postmenopausal women with osteoporosis. METHODS Women who completed the 3-year FREEDOM study were eligible to enter the 7-year open-label FREEDOM Extension in which all participants are scheduled to receive denosumab, since placebo assignment was discontinued for ethical reasons. A total of 4550 women enrolled in the Extension (2343 long-term; 2207 cross-over). In this analysis, women in the long-term and cross-over groups received denosumab for up to 8 and 5 years, respectively. RESULTS Throughout the Extension, sustained reduction of bone turnover markers (BTMs) was observed in both groups. In the long-term group, mean bone mineral density (BMD) continued to increase significantly at each time point measured, for cumulative 8-year gains of 18.4 and 8.3 % at the lumbar spine and total hip, respectively. In the cross-over group, mean BMD increased significantly from the Extension baseline for 5-year cumulative gains of 13.1 and 6.2 % at the lumbar spine and total hip, respectively. The yearly incidence of new vertebral and nonvertebral fractures remained low in both groups. The incidence of adverse and serious adverse events did not increase over time. Through Extension year 5, eight events of osteonecrosis of the jaw and two events of atypical femoral fracture were confirmed. CONCLUSIONS Denosumab treatment for up to 8 years was associated with persistent reductions of BTMs, continued BMD gains, low fracture incidence, and a consistent safety profile.

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When on 26 May 1662 the founding first stone was laid for a new church on the island Nordstrand at the coast of Schleswig, relics of Teresa of Avila (1515-1582) and of the Dutch Carmelite abbess Maria Margaretha ab Angelis (1605-1658) were inserted. This church was built for Dutch dyke builders who were called to reconstruct the island after its destruction by flood in 1634; coming from a Catholic background and from the Dutch Republic which was at war with Spain at that time, the dyke builders and their families were guaranteed religious freedom in the Lutheran duchy of Holstein. In this paper, the reasons for the choice for the Spanish mystic Teresa of Avila and for the Dutch Carmelite abbess Maria Margaretha are discussed. The latter patroness was never beatified but had died in the smell of holiness; after her death several miracles were ascribed to her. It is understandable that migrants brought relics of their appreciated holy persons who would remind them of their homeland. The paper will first shortly introduce the two patronesses of the church. In the second part, the reasons for this choice will be discussed. Behind this translation of relics not only spiritual reasons played a role. The function of the translation of the saints was first to keep up geographical and political connections with the old country (both Spain and the Netherlands), secondly to perpetuate personal-familial relationships (esp. with Maria Margaretha), thirdly to strengthen the confessional identity in a non-Catholic environment. Fourthly the transfer brought a certain model of Christian life and reform to the new place of living, which in the second part of the 17th century became marked as “Jansenist”. The paper shows the transformation of the island into an enclave of Dutch Catholic culture.