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We investigate the emergence of halos and Efimov states in nuclei by use of a newly designed model that combines self-consistent mean-field and three-body descriptions. Recent interest in neutron heavy calcium isotopes makes ^{72}Ca (^{70}Ca+n+n) an ideal realistic candidate on the neutron dripline, and we use it as a representative example that illustrates our broadly applicable conclusions. By smooth variation of the interactions we simulate the crossover from well-bound systems to structures beyond the threshold of binding, and find that halo configurations emerge from the mean-field structure for three-body binding energy less than â¼100 keV. Strong evidence is provided that Efimov states cannot exist in nuclei. The structure that bears the most resemblance to an Efimov state is a giant halo extending beyond the neutron-core scattering length. We show that the observable large-distance decay properties of the wave function can differ substantially from the bulk part at short distances, and that this evolution can be traced with our combination of few- and many-body formalisms. This connection is vital for interpretation of measurements such as those where an initial state is populated in a reaction or by a beta decay.
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Bittersweet nightshade (Solanum dulcamara L.) is a key noncrop host of the potato psyllid (Bactericera cockerelli Sulc), proposed to be a source of the psyllids that colonize potato (Solanum tuberosum L.) fields in the northwestern United States. Here, we describe the broader community of arthropod potato pests, and also predatory arthropods, found in bittersweet nightshade patches. Over 2 yr, we sampled arthropods in patches of this weed spanning the potato-growing region of eastern Washington State. The potato psyllid was the most abundant potato pest that we found, with reproduction of these herbivores recorded throughout much of the growing season where this was measured. Aphid, beetle, and thrips pests of potato also were collected on bittersweet nightshade. In addition to these herbivores, we found a diverse community of >40 predatory arthropod taxa. Spiders, primarily in the Families Dictynidae and Philodromidae, made up 70% of all generalist predator individuals collected. Other generalist predators included multiple species of predatory mites, bugs, and beetles. The coccinellid beetle Stethorus punctillum (Weise) was observed eating psyllid eggs, while the parasitoid wasp Tamarixia triozae (Burks) was observed parasitizing potato psyllid nymphs. Overall, our survey verified the role of bittersweet nightshade as a potato psyllid host, while suggesting that other potato pests also use these plants. At the same time, we found that bittersweet nightshade patches were associated with species-rich communities of natural enemies. Additional work is needed to directly demonstrate movement of pests, and perhaps also predators, from bittersweet nightshade to potato fields.
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Cadeia Alimentar , Hemípteros/fisiologia , Herbivoria , Solanum , Animais , Artrópodes , Hemípteros/crescimento & desenvolvimento , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Comportamento Predatório , Solanum/crescimento & desenvolvimento , WashingtonRESUMO
BACKGROUND: Patients with cyanotic congenital heart disease (CCHD) have a high prevalence of thrombosis, the most frequently described locations being the cerebral and pulmonary vessels. The reported prevalence of both cerebral infarction and pulmonary thrombosis has been highly variable. The aim of this study was to examine the prevalence of both cerebral and pulmonary thrombosis in CCHD according to medical history and imaging. In addition, the role of known erythrocytosis and haemostatic abnormalities as risk factors was evaluated. METHODS AND RESULTS: A cross-sectional descriptive study examining 98 stable adult patients with CCHD with a medical questionnaire, blood samples, MRI of the cerebrum (n=72), multidetector CT imaging (MDCT) of the thorax (n=76) and pulmonary scintigraphy (ventilation/perfusion/single-photon emission computerised tomography/CT) (n=66). The prevalence of cerebral infarction and pulmonary thrombosis according to imaging were 47% and 31%, respectively. Comparing the findings with previous medical history revealed a large under-reporting of thrombosis with only 22% of the patients having a clinical history of stroke and 25% of pulmonary thrombosis. There was no association between the degree of erythrocytosis or haemostatic abnormalities and the prevalence of thrombosis. CONCLUSIONS: Patients with CCHD have a prevalence of both cerebral and pulmonary thrombosis of around 30%-40%, which is much higher than that reported previously. Furthermore, there is a large discrepancy between clinical history and imaging findings, suggesting a high prevalence of silent thrombotic events. Neither erythrocytosis nor haemostatic abnormalities were associated with the prevalence of thrombosis in patients with CCHD. TRIAL REGISTRATION NUMBER: http://www.cvk.sum.dk/CVK/Home/English.aspx (H-KF-2006-4068).
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Cianose/epidemiologia , Cardiopatias Congênitas/epidemiologia , Trombose Intracraniana/epidemiologia , Pulmão/irrigação sanguínea , Trombose/epidemiologia , Adulto , Estudos Transversais , Cianose/diagnóstico , Dinamarca/epidemiologia , Feminino , Cardiopatias Congênitas/diagnóstico , Humanos , Trombose Intracraniana/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Imagem de Perfusão , Valor Preditivo dos Testes , Prevalência , Fatores de Risco , Inquéritos e Questionários , Trombose/diagnóstico , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
Adults with congenital heart disease are a growing population. One of the major challenges in the care of these patients is to prevent thromboembolic episodes. Despite relative young age and no typical cardiovascular risk factors, this cohort has a high prevalence of thrombotic events. It is difficult to use treatment algorithms from the general adult population with acquired heart disease in this heterogeneous population due to special conditions such as myocardial scarring after previous surgery, atypical atrial flutter, prothrombotic conditions and the presence of interatrial shunts. Furthermore, there is a lack of scientific evidence regarding how to prevent thromboembolic events with anticoagulation in adults with congenital heart disease. The aim of this paper is to review the current literature pertaining to anticoagulation in adults with congenital heart disease and hence enable recommendations for which patients are likely to benefit from which anticoagulation treatments, when they should be considered and how these would be carried out.
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Anticoagulantes/uso terapêutico , Cardiopatias Congênitas/complicações , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Adulto , Humanos , Guias de Prática Clínica como AssuntoRESUMO
In one dimension, the study of magnetism dates back to the dawn of quantum mechanics when Bethe solved the famous Heisenberg model that describes quantum behaviour in magnetic systems. In the last decade, one-dimensional (1D) systems have become a forefront area of research driven by the realization of the Tonks-Girardeau gas using cold atomic gases. Here we prove that 1D fermionic and bosonic systems with strong short-range interactions are solvable in arbitrary confining geometries by introducing a new energy-functional technique and obtaining the full spectrum of energies and eigenstates. As a first application, we calculate spatial correlations and show how both ferro- and antiferromagnetic states are present already for small system sizes that are prepared and studied in current experiments. Our work demonstrates the enormous potential for quantum manipulation of magnetic correlations at the microscopic scale.
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BACKGROUND: Long-term survival after the Fontan procedure shows excellent results but is associated with a persistent risk of arrhythmias and exercise intolerance. We aimed to analyze the current burden of clinically relevant arrhythmia and severe exercise intolerance in Danish Fontan patients and furthermore, to estimate the future burden from analysis of mortality and the current burden related to age. METHODS: All Danish citizens with Fontan completion from 1981 to 2009 were identified (n=235). Surviving patients performed exercise test, Holter monitoring, echocardiography, pulmonary function test, and blood sampling and medical history was retrieved from medical records. RESULTS: Twenty-six (11%) patients died or had heart transplantation (HTx) after a mean (± SD) post-Fontan follow-up of 8.3 ± 5.7 years. Excluding perioperative deaths (n=8), a linear probability of HTx-free survival was observed and estimated to 99.1% per year. Prevalence of clinically relevant arrhythmia and severe exercise intolerance increased significantly with age and was found in 32% and 85% of patients ≥ 20 years, respectively. Thus, from survival data and logistic regression models the future prevalence of patients, clinically relevant arrhythmia and severe exercise intolerance were estimated, revealing a considerable augmentation. Furthermore, resting and maximum cardiac index, resting stroke volume index and pulmonary diffusing capacity decreased significantly with age while diastolic and systolic ventricular function was unchanged. CONCLUSIONS: The prevalence of clinically relevant arrhythmia and severe exercise intolerance increased significantly with age in Danish Fontan patients. The future Fontan burden was estimated showing an increase in the prevalence of older patients, clinically relevant arrhythmia, and severe exercise intolerance.
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Arritmias Cardíacas/fisiopatologia , Teste de Esforço/tendências , Tolerância ao Exercício/fisiologia , Técnica de Fontan/tendências , Vigilância da População , Adolescente , Adulto , Fatores Etários , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/epidemiologia , Criança , Estudos Transversais , Dinamarca/epidemiologia , Feminino , Seguimentos , Previsões , Humanos , Masculino , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Patients with cyanotic congenital heart disease (CCHD) have haemostatic abnormities associated with bleeding and thrombo-embolic events. The haemostatic abnormalities are not fully understood, but recent studies indicate that elevated haematocrit and fibrinogen function may be of importance. The aim of this study was to characterise the haemostatic profile and examine the potential role of haematocrit on clot formation and strength in CCHD patients. Furthermore to examine whether CCHD patients with history of haemoptysis have diminished fibrinogen function compared to those without haemoptysis. METHODS: In a prospective study 75 adult CCHD patients had haematocrit, platelet count, and plasma fibrinogen concentration examined. Furthermore thrombelastography(TEG) as well as TEG Functional Fibrinogen(TEG FF) assay evaluating fibrinogen function(FLEV) was performed. Data were compared with historical data regarding previous haemoptysis in CCHD patients. RESULTS: Haematocrit was 57 ± 8% and platelet counts in the lower normal range. TEG revealed a hypocoagulable condition with impaired clot formation. TEG values were correlated to haematocrit, indicating that elevated haematocrit causes impaired clot formation and strength. Despite high levels of plasma fibrinogen, TEG FF demonstrated that FLEV was diminished and negatively correlated to haematocrit. Furthermore CCHD patients with previous history of haemoptysis had significantly lower FLEV compared to CCHD patients without haemoptysis. CONCLUSION: Patients with CCHD are hypocoagulable mainly due to impaired fibrinogen function. Despite a low platelet count, platelet function does not seem to be severely affected in CCHD patients. Haemostasis, and especially fibrinogen function, is negatively affected by elevated haematocrit, and fibrinogen function is diminished in CCHD patients with haemoptysis.
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Fibrinogênio/fisiologia , Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/diagnóstico , Hemostasia/fisiologia , Adulto , Cianose , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas/métodos , Estudos Prospectivos , Tromboelastografia/métodos , Tempo de Coagulação do Sangue Total/métodosRESUMO
BACKGROUND: Patients with cyanotic congenital heart disease(CCHD) have haemostatic abnormalities, which result in an increased risk of bleeding. The cause is unknown, but recent studies have indicated that an elevated haematocrit, which is present in cyanotic patients, could be an important factor. The aim of this study was to characterize the haemostatic profile, examine how changes in haematocrit affect the haemostatic profile, and whether a haematocrit reduction could terminate bleeding in CCHD patients. METHODS: This was a prospective, multicenter study. The haemostatic profile consisting of haematocrit, platelet count and thrombelastography(TEG) was characterized in ninety-eight CCHD patients. To evaluate the influence of haematocrit on the haemostatic profile, 21 of the patients underwent phlebotomy and 16 patients received treatment with an iron supplement. Furthermore ten patients with haemoptysis underwent phlebotomy. The haemostatic profile was reevaluated after interventions. RESULTS: TEG revealed that patients with CCHD and elevated haematocrit were hypocoagulable due to reduced clot formation and strength. Furthermore a positive correlation between elevated haematocrit and hypocoagulability was present. Interventions such as phlebotomy and treatment with supplemental iron causing significant haematocrit changes confirmed the correlation between haematocrit and the haemostatic profile. Finally a haematocrit reduction by phlebotomy successfully terminated haemoptysis in ten CCHD patients. CONCLUSION: Patients with CCHD and elevated haematocrit are hypocoagulable. The hypocoagulable haemostatic profile is positively correlated to increasing haematocrit. An intervention, which increases or decreases haematocrit, changes the haemostatic profile. A haematocrit reduction seems to improve the haemostatic profile, and may thereby terminate bleeding. However, these results warrant further studies.
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Cianose/sangue , Cianose/diagnóstico , Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/diagnóstico , Hemostasia/fisiologia , Adulto , Cianose/epidemiologia , Feminino , Cardiopatias Congênitas/epidemiologia , Hematócrito/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tromboelastografia/métodosRESUMO
After the Fontan procedure, patients face an increased risk for thromboembolic events (TE). The etiology for this increased thrombogenecity is incompletely understood. This study aimed to determine the prevalence of TE in Danish Fontan patients and to bring new insights into the etiology of TE. Using a population-based design, we retrospectively identified all TEs in 210 Fontan patients. Whole blood assays (thromboelastography, thromboelastography functional fibrinogen and Multiplate) reflecting global hemostasis, clot strength and platelet aggregation were analyzed prospectively in 112 patients and plasma was analyzed in 76 patients for biomarkers reflecting endothelial-, glycocalyx-, platelet-, and fibrinolysis function (histone-complexed DNA fragments, Protein C, soluble CD40 ligand, soluble thrombomodulin, syndecan-1, tissue-type plasminogen activator). The results were compared in groups stratified according to age, antithrombotic therapy, TE, and glycocalyx degradation (syndecan-1 < or ≥ median). Correlation between biomarkers and demographic-, anatomical-, clinical- and biochemical parameters was investigated. The prevalence of TE was 8.1 % after a mean follow-up of 8.4 years. None of the stratified groups demonstrated evidence of hypercoagulability in the whole blood assays and no unexpected significant differences were found between the groups. All biomarkers, except protein C, correlated with one another and after stratification of glycocalyx degradation only syndecan-1 levels ≥ median correlated with other biomarkers. The prevalence of TEs was 8.1 % after mean follow-up of 8.4 years. Overall, the hemostatic profile appeared normal, however, in a subset of patients, evidence of some endothelial activation/damage including glycocalyx degradation and fibrinolysis was found, identifying a potentially more thrombogenic group.
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Técnica de Fontan/efeitos adversos , Vigilância da População , Complicações Pós-Operatórias , Tromboembolia/epidemiologia , Adolescente , Biomarcadores/sangue , Coagulação Sanguínea , Estudos Transversais , Dinamarca/epidemiologia , Impedância Elétrica , Feminino , Seguimentos , Cardiopatias Congênitas/cirurgia , Humanos , Masculino , Agregação Plaquetária , Prevalência , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Tromboelastografia , Tromboembolia/sangue , Tromboembolia/etiologia , Fatores de TempoRESUMO
BACKGROUND: The incidence of children born with functional univentricular heart (UVH) and their prognosis presumably changed substantially in recent years. This is due to introduction of fetal echocardiography and potential termination of pregnancy (TOP) when UVH is diagnosed (UVH TOP), and to improvements in treatment. We aimed to explore changes in incidence, to estimate changes in survival, and to describe predictors of mortality in UVH patients. METHODS: Using a population-based design we identified all UVH cases in Denmark from 1977 to 2009. RESULTS: 703 UVH live births and 106 UVH TOP were identified. A dramatic decrease in birth incidence of UVH patients and a corresponding increase in UVH TOP was observed in recent years. Mean incidence rate of UVH (live births and UVH TOP) was 0.39 per 1000 births. In adjusted analysis survival improved significantly from birth era 1977-1989 to 1990-1999 (HR 2.65, 95% confidence interval (CI), 2.06-3.42) but not significantly from 1990-1999 to 2000-2009 (HR 0.77, 95% CI, 0.57-1.05). In the birth era 2000-2009, the lowest five-year survival was seen with hypoplastic left heart syndrome (HLHS) (18.8%), whereas the best survival was seen with tricuspid atresia (79.8%). Adjusted risk of death was 7.3 times higher in the HLHS group compared to the tricuspid atresia group (95% CI, 3.94-13.47). CONCLUSIONS: This study demonstrates a dramatic decrease in birth incidence of UVH patients most probably due to a corresponding increase in UVH TOP. Despite survival improved after introduction of Fontan surgery, survival has not improved significantly during the last 20years.
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Síndrome do Coração Esquerdo Hipoplásico/diagnóstico , Síndrome do Coração Esquerdo Hipoplásico/mortalidade , Vigilância da População/métodos , Atresia Tricúspide/diagnóstico , Atresia Tricúspide/mortalidade , Adolescente , Adulto , Criança , Pré-Escolar , Dinamarca/epidemiologia , Feminino , Técnica de Fontan/mortalidade , Técnica de Fontan/tendências , Humanos , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Incidência , Masculino , Pessoa de Meia-Idade , Gravidez , Sistema de Registros , Taxa de Sobrevida/tendências , Atresia Tricúspide/cirurgia , Adulto JovemRESUMO
The virial expansion method is applied within a harmonic approximation to an interacting N-body system of identical fermions. We compute the canonical partition functions for two and three particles to get the two lowest orders in the expansion. The energy spectrum is carefully interpolated to reproduce ground-state properties at low temperature and the noninteracting high-temperature limit of constant virial coefficients. This resembles the smearing of shell effects in finite systems with increasing temperature. Numerical results are discussed for the second and third virial coefficients as functions of dimension, temperature, interaction, and transition temperature between low- and high-energy limits.
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We describe a method to compute thermodynamic quantities in the harmonic approximation for identical bosons and fermions in an external confining field. We use the canonical partition function where only energies and their degeneracies enter. The number of states of given energy and symmetry is found by separating the center-of-mass motion, and by counting the remaining states of given symmetry and excitation energy of the relative motion. The oscillator frequencies that enter the harmonic Hamiltonian can be derived from realistic model parameters, and the method corresponds to an effective interaction approach based on harmonic interactions. To demonstrate the method, we apply it to systems in two dimensions. Numerical calculations are compared to a brute force method, which is considerably more computationally intensive.
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Algoritmos , Modelos Teóricos , Teoria Quântica , Termodinâmica , Simulação por ComputadorRESUMO
We calculate the energy and wave functions of two particles confined to two spatial dimensions interacting via arbitrary anisotropic potentials with negative or zero net volume. The general rigorous analytic expressions are given in the weak coupling limit where universality or model independence are approached. The monopole part of anisotropic potentials is crucial in the universal limit. We illustrate the universality with a system of two arbitrarily polarized cold dipolar molecules in a bilayer. We discuss the transition to universality as a function of polarization and binding energy and compare analytic and numerical results obtained by the stochastic variational method. The universal limit is essentially reached for experimentally accessible strengths.
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We discuss the three-body decay mechanisms of many-body resonances. Sequential decays proceed via two-body configurations after emission of the third particle. In direct decay all three particles leave their interaction regions simultaneously. The intermediate paths within the interaction regions are not observables and are only accessible through models. The momentum distributions carry, apart from polarization, all possible information about decay modes and resonance structure. In this context we discuss detailed results for the decay of the (9)Be(5/2(-)) resonance.
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We compute energy distributions of three particles emerging from decaying many-body resonances. We reproduce the measured energy distributions from decays of two archetypal states chosen as the lowest 0+ and 1+ resonances in 12C populated in beta decays. These states are dominated by sequential, through the 8Be ground state, and direct decays, respectively. These decay mechanisms are reflected in the "dynamic" evolution from small, cluster or shell-model states, to large distances, where the coordinate or momentum space continuum wave functions are accurately computed.
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OBJECTIVE: The aim of the present study was to quantify the effects on skin in post-menopausal women of a novel dietary supplement (Imedeen Prime Renewal) that contained soy extract, fish protein polysaccharides, extracts from white tea, grape seed and tomato, vitamins C and E as well as zinc and chamomile extract. DESIGN: The study was a 6-month double blind, placebo controlled, randomized study on healthy post-menopausal females. SETTING: The study was performed at a commercial Contract Research Organisation (TJ Stephens & Associates Inc., TX, USA). INTERVENTIONS: Two tablets of Imedeen Prime Renewal or placebo were given twice daily for 6 months. SUBJECTS: Thirty-eight (active group) and 42 (placebo group) subjects completed the study out of 100. RESULTS: Clinical grading showed that the active group had a significantly greater improvement (P < 0.05) compared to placebo for the face after 6 months treatment for: forehead, periocular and perioral wrinkles, mottled pigmentation, laxity, sagging, under eye dark circles and overall apperance; skin on the décolletage after 2, 3 and 6 months treatment and skin on the hand after 3 and 6 months treatment. Photo evaluation showed that the active group had a significantly greater improvement (P < 0.05) on the face after 3 and 6 months for several parameters. Ultrasound measurements showed that the active group had a significantly greater improvement (P < 0.0001) for density measurements after 6 months treatment. CONCLUSION: In summary, this novel dietary supplement, Imedeen Prime Renewal, provides improved condition, structure and firmness of the skin in post-menopausal women after 6 months.
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Envelhecimento/fisiologia , Extratos Vegetais/farmacologia , Fenômenos Fisiológicos da Pele , Pele/efeitos dos fármacos , Idoso , Envelhecimento/efeitos dos fármacos , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Pele/diagnóstico por imagem , Pele/patologia , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Resultado do Tratamento , UltrassonografiaRESUMO
We investigate the effects of the nearly fulfilled Efimov conditions on the properties of three-body resonances. Using the hyper-spheric adiabatic expansion method we compute energy distributions of fragments in a three-body decay of a nuclear resonance. As a realistic example we investigate the 1- state in the halo nucleus 11Li within a three-body model 9Li + n +n model. Characteristic features appear as sharp peaks in the energy distributions. Their origin, as in the Efimov effect, is in the large two-body s-wave scattering lengths between the pairs of fragments.
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We study two-body correlations in systems of identical bosons. We use a Faddeev type of decomposition of the wave function where all pairs of particles are treated equally. At large scattering length appears a series of Efimov-like states, i.e., spatially extended, model-independent many-body bound states inside the trap. They may play a role in the decay of Bose-Einstein condensates.