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1.
Phys Rev Lett ; 127(24): 242501, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34951807

RESUMO

The microscopic structure of the low-energy electric dipole response, commonly denoted as pygmy dipole resonance (PDR), was studied for ^{120}Sn in a ^{119}Sn(d,pγ)^{120}Sn experiment. Unprecedented access to the single-particle structure of excited 1^{-} states below and around the neutron-separation threshold was obtained by comparing experimental data to predictions from a novel theoretical approach. The novel approach combines detailed structure input from energy-density functional plus quasiparticle-phonon model theory with reaction theory to obtain a consistent description of both the structure and reaction aspects of the process. The presented results show that the understanding of one-particle-one-hole structures of the 1^{-} states in the PDR region is crucial to reliably predict properties of the PDR and its contribution to nucleosynthesis processes.

2.
Phys Rev Lett ; 125(23): 232501, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33337204

RESUMO

The neutron-rich nuclei in the N=28 island of inversion have attracted considerable experimental and theoretical attention, providing great insight into the evolution of shell structure and nuclear shape in exotic nuclei. In this work, for the first time, quadrupole collectivity is assessed simultaneously on top of the 3/2^{-} ground state and the 7/2^{-} shape-coexisting isomer of ^{43}S, putting the unique interpretation of shape and configuration coexistence at N=27 and 28 in the sulfur isotopic chain to the test. From an analysis of the electromagnetic transition strengths and quadrupole moments predicted within the shell model, it is shown that the onset of shape coexistence and the emergence of a simple collective structure appear suddenly in ^{43}S with no indication of such patterns in the N=27 isotone ^{45}Ar.

3.
Phys Rev Lett ; 125(10): 102503, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32955313

RESUMO

New experimental data on the neutron single-particle character of the Pygmy Dipole Resonance (PDR) in ^{208}Pb are presented. They were obtained from (d,p) and resonant proton scattering experiments performed at the Q3D spectrograph of the Maier-Leibnitz Laboratory in Garching, Germany. The new data are compared to the large suite of complementary, experimental data available for ^{208}Pb and establish (d,p) as an additional, valuable, experimental probe to study the PDR and its collectivity. Besides the single-particle character of the states, different features of the strength distributions are discussed and compared to large-scale shell model (LSSM) and energy-density functional plus quasiparticle-phonon model theoretical approaches to elucidate the microscopic structure of the PDR in ^{208}Pb.

4.
Phys Rev Lett ; 121(8): 082502, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30192612

RESUMO

Neutron-deficient selenium isotopes are thought to undergo a rapid shape change from a prolate deformation near the line of beta stability towards oblate deformation around the line of N=Z. The point at which this shape change occurs is unknown, with inconsistent predictions from available theoretical models. A common feature in the models is the delicate nature of the point of transition, with the introduction of even a modest spin to the system sufficient to change the ordering of the prolate and oblate configurations. We present a measurement of the quadrupole moment of the first-excited state in radioactive ^{72}Se-a potential point of transition-by safe Coulomb excitation. This is the first low-energy Coulomb excitation to be performed with a rare-isotope beam at the reaccelerated beam facility at the National Superconducting Cyclotron Laboratory. By demonstrating a negative spectroscopic quadrupole moment for the first-excited 2^{+} state, it is found that any low-spin shape change in neutron-deficient selenium does not occur until ^{70}Se.

5.
Phys Rev Lett ; 114(19): 192504, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26024168

RESUMO

The experimental E1 strength distribution below 4 MeV in rare-earth nuclei suggests a local breaking of isospin symmetry. In addition to the octupole states, additional J^{π}=1^{-} states with enhanced E1 strength have been observed in rare-earth nuclei by means of (γ,γ') experiments. By reproducing the experimental results, the spdf interacting boson model calculations provide further evidence for the formation of an α cluster in medium-mass nuclei and might provide a new understanding of the origin of low-lying E1 strength.

6.
Eur Heart J Cardiovasc Imaging ; 19(5): 574-582, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29136120

RESUMO

Aims: The aim of this study was to determine the value of T2 mapping for the non-invasive assessment of myocardial inflammation in different stages of systolic left ventricular dysfunction in dilated cardiomyopathy (DCM) in comparison with endomyocardial biopsy (EMB). Methods and results: A total of 132 subjects were enrolled between 2013 and 2016 (62 controls and 70 patients with DCM). All patients underwent CMR at 1.5 T and received coronary angiogram and EMB. CMR applied standard protocols including T2 mapping with Gradient And SpinEcho sequence (GRASE). Global T2 relaxation time was significantly increased in patients with DCM compared to the healthy controls (T2 time DCM vs. controls: 65.9 ± 6.2 vs. 60.0 ± 4.2 ms; P < 0.001). Of note, patients with the presence of inflammatory cells in EMB exhibited further elevation of T2 values (T2 time in patients with the presence of inflammatory cells vs. T2 time in patients without: 68.8 ± 5.8 vs. 64.7 ± 5.9 ms; P = 0.02). Receiver operating characteristic analysis of our data deciphered a global myocardial T2 time >65.3 ms as the best cut-off for distinction between the healthy controls and patients with myocardial inflammation [sensitivity 93%, specificity 90%, P < 0.01, area under the curve (AUC) 0.95]. In patients with DCM, this threshold identified patients with biopsy-proven inflammation with a sensitivity of 79% and specificity 58% (AUC 0.72). Conclusion: In patients with DCM and presence of inflammatory cells in the myocardium, myocardial T2 relaxation times may help to non-invasively detect myocardial inflammation. Although there is an overlap of T2 values between patients and healthy controls, T2 mapping may facilitate the identification of patients who may benefit from EMB for therapeutic decision-making.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/patologia , Imagem Cinética por Ressonância Magnética/métodos , Miocardite/diagnóstico por imagem , Miocardite/patologia , Adulto , Idoso , Área Sob a Curva , Biópsia por Agulha , Estudos de Casos e Controles , Feminino , Seguimentos , Alemanha , Hospitais Universitários , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Medição de Risco
7.
Biol Open ; 6(7): 956-966, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28522431

RESUMO

Ionocytes of euryhaline teleost fish secrete NaCl, under regulation by serine and threonine kinases, including with-no-lysine kinase (WNK1) and p38 mitogen-activated protein kinase (MAPK). Mummichogs (Fundulus heteroclitus L.) were acclimated to freshwater (FW), full strength seawater (SW) and hypersaline conditions (2SW). Immunocytochemistry of ionocytes in opercular epithelia of fish acclimated to SW and 2SW revealed that WNK1-anti-pT58 phosphoantibody localized strongly to accessory cells and was present in the cytosol of ionocytes, close to cystic fibrosis transmembrane conductance regulator (CFTR) in the apical membrane and the sodium potassium 2 chloride cotransporter (NKCC) in the basolateral membrane. In FW acclimated fish, WNK1 localized to a sub-apical zone, did not colocalize with apical membrane-located sodium chloride cotransporter (NCC), and typically was present in one cell of paired ionocytes and in some single ionocytes. Forskolin treatment (10 µM, 30 min) increased WNK1 immunofluorescence in SW ionocytes only, while hypertonicity had little effect, compared to controls. Anti-p38-MAPK antibody localized to the cytosolic compartment. The distribution of WNK1 and p38MAPK is consistent with a proximal position in regulatory cascades, rather than directly affecting transporters. The strong staining of accessory cells by WNK1 phosphoantibody infers an osmoregulatory function for WNK.

8.
Mil Med ; 164(7): 471-4, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10414060

RESUMO

OBJECTIVE: This study assesses the sensitivity of self-collected rectovaginal culture specimens for group B Streptococcus by pregnant patients. METHODS: A volunteer sample of 240 pregnant women at 28 weeks gestation self-collected rectovaginal culture swabs to screen for the presence of group B Streptococcus. The patients' physicians collected second specimens for comparison. RESULTS: Twenty-four of 240 women grew group B Streptococcus on at least one culture (incidence, 10%). Twenty physician-collected specimens and 19 patient-collected specimens were positive (83 and 79% sensitivity, respectively). Fifteen patients (62.5%) had both physician-collected and patient-collected cultures grow group B Streptococcus. Cohen's kappa (kappa = 0.75) indicates a high degree of agreement between patient-collected and physician-collected cultures. CONCLUSIONS: Pregnant women are as likely as their attending physicians to obtain positive cultures for group B Streptococcus by self-collection of rectovaginal swabs.


Assuntos
Programas de Rastreamento/métodos , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/microbiologia , Autocuidado/métodos , Manejo de Espécimes/métodos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae , Adulto , Feminino , Florida , Humanos , Medicina Naval , Gravidez , Reto/microbiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Vagina/microbiologia
10.
Am Fam Physician ; 61(12): 3639-48, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10892635

RESUMO

Dysphagia is a problem that commonly affects patients cared for by family physicians in the office, as hospital inpatients and as nursing home residents. Familiar medical problems, including cerebrovascular accidents, gastroesophageal reflux disease and medication-related side effects, often lead to complaints of dysphagia. Stroke patients are at particular risk of aspiration because of dysphagia. Classifying dysphagia as oropharyngeal, esophageal and obstructive, or neuromuscular symptom complexes leads to a successful diagnosis in 80 to 85 percent of patients. Based on the patient history and physical examination, barium esophagram and/or gastroesophageal endoscopy can confirm the diagnosis. Special studies and consultation with subspecialists can confirm difficult diagnoses and help guide treatment strategies.


Assuntos
Transtornos de Deglutição/etiologia , Esôfago/patologia , Esôfago/fisiopatologia , Orofaringe/patologia , Orofaringe/fisiopatologia , Algoritmos , Constrição Patológica/complicações , Constrição Patológica/diagnóstico , Deglutição/fisiologia , Transtornos de Deglutição/induzido quimicamente , Transtornos de Deglutição/fisiopatologia , Diagnóstico Diferencial , Humanos , Doenças Neuromusculares/complicações , Doenças Neuromusculares/diagnóstico
11.
J Am Board Fam Pract ; 9(5): 319-23, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8884669

RESUMO

BACKGROUND: Sudden infant death syndrome (SIDS) kills more than 6000 infants annually in the United States. Researchers have described prone sleep position as a risk factor for SIDS. A greater than 50 percent reduction in SIDS has been reported in countries where the predominant sleep position changed from prone to supine. In 1992 the American Academy of Pediatrics (AAP) recommended that healthy infants be placed in a supine position at bedtime. Previous studies of pediatric practices reported a 60 percent compliance with the recommendation. This study describes the self-reported compliance with the AAP recommendation by a cohort of family physicians. METHODS: Three hundred members of the Uniformed Services Academy of Family Physicians were mailed a questionnaire about their recommendations regarding infant sleep position. RESULTS: The response rate was 77 percent. Sixty-two percent of the respondents usually or always encourage supine sleep position. Twenty-one percent usually or always discourage the supine sleep position. CONCLUSIONS: This cohort of family physicians encourages the supine sleep position at rates similar to reported cohorts of pediatricians. Reasons for the limited endorsement of the AAP recommendation were not explained by the results of this study.


Assuntos
Atitude do Pessoal de Saúde , Medicina de Família e Comunidade/normas , Cuidado do Lactente/normas , Sono , Morte Súbita do Lactente/prevenção & controle , Decúbito Dorsal , Adulto , Idoso , Estudos de Coortes , Medicina de Família e Comunidade/educação , Feminino , Humanos , Lactente , Cuidado do Lactente/métodos , Recém-Nascido , Internato e Residência , Masculino , Pessoa de Meia-Idade , Medicina Militar , Pediatria/normas , Médicos de Família/educação , Médicos de Família/psicologia , Sociedades Médicas/normas , Estados Unidos
12.
J Immunol ; 166(6): 4042-8, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11238652

RESUMO

The early response cytokines, TNF and IL-1, have overlapping biologic effects that may function to propagate, amplify, and coordinate host responses to microbial challenges. To determine whether signaling from these early response cytokines is essential to orchestrating innate immune responses to intrapulmonary bacteria, the early inflammatory events induced by instillation of Escherichia coli into the lungs were compared in wild-type (WT) mice and mice deficient in both TNF receptor 1 (TNFR1) and the type I IL-1 receptor (IL1R1). Neutrophil emigration and edema accumulation induced by E. coli were significantly compromised by TNFR1/IL1R1 deficiency. Neutrophil numbers in the circulation and within alveolar septae did not differ between WT and TNFR1/IL1R1 mice, suggesting that decreased neutrophil emigration did not result from decreased sequestration or delivery of intravascular neutrophils. The nuclear translocation of NF-kappa B and the expression of the chemokine macrophage inflammatory protein-2 did not differ between WT and TNFR1/IL1R1 lungs. However, the concentration of the chemokine KC was significantly decreased in the bronchoalveolar lavage fluids of TNFR1/IL1R1 mice compared with that in WT mice. Thus, while many of the molecular and cellular responses to E. coli in the lungs did not require signaling by either TNFR1 or IL1R1, early response cytokine signaling was critical to KC expression in the pulmonary air spaces and neutrophil emigration from the alveolar septae.


Assuntos
Antígenos CD/fisiologia , Infecções por Escherichia coli/imunologia , Pneumonia Bacteriana/imunologia , Receptores de Interleucina-1/fisiologia , Receptores do Fator de Necrose Tumoral/fisiologia , Transporte Ativo do Núcleo Celular/genética , Transporte Ativo do Núcleo Celular/imunologia , Animais , Antígenos CD/genética , Núcleo Celular/genética , Núcleo Celular/imunologia , Núcleo Celular/metabolismo , Quimiocina CXCL1 , Quimiocina CXCL2 , Quimiocinas/biossíntese , Quimiocinas CXC , Citocinas/biossíntese , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/patologia , Imunidade Inata/genética , Inflamação/genética , Inflamação/imunologia , Contagem de Leucócitos , Pulmão/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Infiltração de Neutrófilos/genética , Infiltração de Neutrófilos/imunologia , Pneumonia Bacteriana/genética , Pneumonia Bacteriana/patologia , Receptores de Interleucina-1/deficiência , Receptores de Interleucina-1/genética , Receptores do Fator de Necrose Tumoral/deficiência , Receptores do Fator de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral , Fatores de Tempo
13.
J Clin Psychopharmacol ; 21(3): 268-72, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11386489

RESUMO

The purpose of this investigation was to describe the pharmacokinetics of sublingual triazolam in children. Nine healthy children (64-98 months old) received 0.25 or 0.375 mg of sublingual triazolam before dental treatment. Plasma triazolam concentrations were measured by gas chromatography/mass spectrometry and analyzed by noncompartmental methods. The peak concentration was 4.9 +/- 2.0 ng/mL (mean +/- SD), time to peak was 75 +/- 32 minutes, the elimination half-life was 91 +/- 32 minutes, and apparent clearance was 17.6 +/- 8.8 mL x kg(-1) x min(-1). Children were tested for gait ataxia, amnesia, and diplopia during a screening session and again after triazolam. Ninety minutes after drug administration, seven of nine children demonstrated ataxia, and three of nine demonstrated amnesia. Peak triazolam concentrations were similar in children with or without ataxia, but they were significantly higher in children with amnesia compared with those without amnesia. Six children demonstrated diplopia 30 and 120 minutes after triazolam; however, peak triazolam concentrations were similar in both groups. Sublingual administration was an acceptable alternative route of triazolam delivery in children.


Assuntos
Ansiolíticos/farmacocinética , Assistência Odontológica para Crianças , Triazolam/farmacocinética , Administração Sublingual , Amnésia/induzido quimicamente , Ansiolíticos/administração & dosagem , Ansiolíticos/sangue , Área Sob a Curva , Ataxia/induzido quimicamente , Criança , Pré-Escolar , Assistência Odontológica para Crianças/métodos , Diplopia/induzido quimicamente , Feminino , Humanos , Modelos Lineares , Masculino , Triazolam/administração & dosagem , Triazolam/sangue
14.
Anesthesiology ; 84(5): 1060-7, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8623999

RESUMO

BACKGROUND: To determine whether parental presence during induction of anesthesia is an effective preoperative behavioral intervention, a randomized controlled trial with children undergoing outpatient surgery was conducted. METHODS: Eighty-four children were randomly assigned to a parent-present or parent-absent group. Using multiple behavioral and physiologic measures of anxiety, the effect of the intervention on the children and their parents was assessed. Predictors for the response to the intervention were examined using multivariate linear regression analysis. RESULTS: When the intervention group (parent-present) was compared to the control group (parent-absent), overall there were no significant differences in any of the behavioral or physiologic measures of anxiety tested during induction of anesthesia. Using the child's serum cortisol concentration as the outcome, parental presence, the child's age and baseline temperament, and trait anxiety of the parent, were identified as predictors of the child's anxiety during induction. Analysis of variance demonstrated that three groups showed diminished cortisol concentrations with parental presence: children older than 4 yr (P = 0.001), children whose parent had a low trait anxiety (P = 0.02), and children who had a low baseline level of activity as assessed by temperament (P = 0.05). CONCLUSIONS: Children who were older than 4 yr or those with a parent with a low trait anxiety or who had a low baseline level of activity/temperament benefited from parental presence during induction.


Assuntos
Anestesia , Comportamento Infantil , Pais , Ansiedade/prevenção & controle , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
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