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Muonic atom spectroscopy-the measurement of the x rays emitted during the formation process of a muonic atom-has a long standing history in probing the shape and size of nuclei. In fact, almost all stable elements have been subject to muonic atom spectroscopy measurements and the absolute charge radii extracted from these measurements typically offer the highest accuracy available. However, so far only targets of at least a few hundred milligram could be used as it required to stop a muon beam directly in the target to form the muonic atom. We have developed a new method relying on repeated transfer reactions taking place inside a 100 bar hydrogen gas cell with an admixture of 0.25% deuterium that allows us to drastically reduce the amount of target material needed while still offering an adequate efficiency. Detailed simulations of the transfer reactions match the measured data, suggesting good understanding of the processes taking place inside the gas mixture. As a proof of principle we demonstrate the method with a measurement of the 2p-1s muonic x rays from a 5 µ g gold target.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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There is sparse direct experimental evidence that atomic nuclei can exhibit stable "pear" shapes arising from strong octupole correlations. In order to investigate the nature of octupole collectivity in radium isotopes, electric octupole (E3) matrix elements have been determined for transitions in ^{222,228}Ra nuclei using the method of sub-barrier, multistep Coulomb excitation. Beams of the radioactive radium isotopes were provided by the HIE-ISOLDE facility at CERN. The observed pattern of E3 matrix elements for different nuclear transitions is explained by describing ^{222}Ra as pear shaped with stable octupole deformation, while ^{228}Ra behaves like an octupole vibrator.
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There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate CP violation and hence probe physics beyond the Standard Model of particle physics. Isotopes of both radon and radium have been identified as candidates for such measurements. Here, we observed the low-lying quantum states in 224Rn and 226Rn by accelerating beams of these radioactive nuclei. We show that radon isotopes undergo octupole vibrations but do not possess static pear-shapes in their ground states. We conclude that radon atoms provide less favourable conditions for the enhancement of a measurable atomic electric-dipole moment.
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BACKGROUND: Bakuchiol is a phytochemical that has demonstrated cutaneous antiageing effects when applied topically. Early studies have suggested that bakuchiol is a functional analogue of topical retinoids, as both compounds have been shown to induce similar gene expression in the skin and lead to improvement of cutaneous photodamage. No in vivo studies have compared the two compounds for efficacy and side-effects. OBJECTIVES: To compare the clinical efficacy and side-effect profiles of bakuchiol and retinol in improving common signs of cutaneous facial ageing. METHODS: This was a randomized, double-blind, 12-week study in which 44 patients were asked to apply either bakuchiol 0·5% cream twice daily or retinol 0·5% cream daily. A facial photograph and analytical system was used to obtain and analyse high-resolution photographs of patients at 0, 4, 8 and 12 weeks. Patients also completed tolerability assessment questions to review side-effects. During study visits, a board-certified dermatologist, blinded to study group assignments, graded pigmentation and redness. RESULTS: Bakuchiol and retinol both significantly decreased wrinkle surface area and hyperpigmentation, with no statistical difference between the compounds. The retinol users reported more facial skin scaling and stinging. CONCLUSIONS: Our study demonstrates that bakuchiol is comparable with retinol in its ability to improve photoageing and is better tolerated than retinol. Bakuchiol is promising as a more tolerable alternative to retinol.
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Fenóis/administração & dosagem , Envelhecimento da Pele/efeitos dos fármacos , Luz Solar/efeitos adversos , Vitamina A/administração & dosagem , Adulto , Método Duplo-Cego , Face , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/induzido quimicamente , Dor/epidemiologia , Medição da Dor , Fenóis/efeitos adversos , Estudos Prospectivos , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos da radiação , Creme para a Pele/administração & dosagem , Creme para a Pele/efeitos adversos , Pigmentação da Pele/efeitos dos fármacos , Pigmentação da Pele/efeitos da radiação , Resultado do Tratamento , Vitamina A/efeitos adversosRESUMO
The first 2^{+} and 3^{-} states of the doubly magic nucleus ^{132}Sn are populated via safe Coulomb excitation employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the highly efficient MINIBALL array. The ^{132}Sn ions are accelerated to an energy of 5.49 MeV/nucleon and impinged on a ^{206}Pb target. Deexciting γ rays from the low-lying excited states of the target and the projectile are recorded in coincidence with scattered particles. The reduced transition strengths are determined for the transitions 0_{g.s.}^{+}â2_{1}^{+}, 0_{g.s.}^{+}â3_{1}^{-}, and 2_{1}^{+}â3_{1}^{-} in ^{132}Sn. The results on these states provide crucial information on cross-shell configurations which are determined within large-scale shell-model and Monte Carlo shell-model calculations as well as from random-phase approximation and relativistic random-phase approximation. The locally enhanced B(E2;0_{g.s.}^{+}â2_{1}^{+}) strength is consistent with the microscopic description of the structure of the respective states within all theoretical approaches. The presented results of experiment and theory can be considered to be the first direct verification of the sphericity and double magicity of ^{132}Sn.
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Fast-neutron-induced fission of ^{238}U at an energy just above the fission threshold is studied with a novel technique which involves the coupling of a high-efficiency γ-ray spectrometer (MINIBALL) to an inverse-kinematics neutron source (LICORNE) to extract charge yields of fission fragments via γ-γ coincidence spectroscopy. Experimental data and fission models are compared and found to be in reasonable agreement for many nuclei; however, significant discrepancies of up to 600% are observed, particularly for isotopes of Sn and Mo. This indicates that these models significantly overestimate the standard 1 fission mode and suggests that spherical shell effects in the nascent fission fragments are less important for low-energy fast-neutron-induced fission than for thermal neutron-induced fission. This has consequences for understanding and modeling the fission process, for experimental nuclear structure studies of the most neutron-rich nuclei, for future energy applications (e.g., Generation IV reactors which use fast-neutron spectra), and for the reactor antineutrino anomaly.
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This corrects the article DOI: 10.1103/PhysRevLett.116.022701.
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Neutron-rich {96,98}Sr isotopes have been investigated by safe Coulomb excitation of radioactive beams at the REX-ISOLDE facility. Reduced transition probabilities and spectroscopic quadrupole moments have been extracted from the differential Coulomb excitation cross sections. These results allow, for the first time, the drawing of definite conclusions about the shape coexistence of highly deformed prolate and spherical configurations. In particular, a very small mixing between the coexisting states is observed, contrary to other mass regions where strong mixing is present. Experimental results have been compared to beyond-mean-field calculations using the Gogny D1S interaction in a five-dimensional collective Hamiltonian formalism, which reproduce the shape change at N=60.
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The isospin mixing was deduced in the compound nucleus ^{80}Zr at an excitation energy of E^{*}=54 MeV from the γ decay of the giant dipole resonance. The reaction ^{40}Ca+^{40}Ca at E_{beam}=136 MeV was used to form the compound nucleus in the isospin I=0 channel, while the reaction ^{37}Cl+^{44}Ca at E_{beam}=95 MeV was used as the reference reaction. The γ rays were detected with the AGATA demonstrator array coupled with LaBr_{3}:Ce detectors. The temperature dependence of the isospin mixing was obtained and the zero-temperature value deduced. The isospin-symmetry-breaking correction δ_{C} used for the Fermi superallowed transitions was extracted and found to be consistent with ß-decay data.
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Excited states of the neutron-rich nuclei (97,99)Rb were populated for the first time using the multistep Coulomb excitation of radioactive beams. Comparisons of the results with particle-rotor model calculations provide clear identification for the ground-state rotational band of (97)Rb as being built on the πg(9/2) [431] 3/2(+) Nilsson-model configuration. The ground-state excitation spectra of the Rb isotopes show a marked distinction between single-particle-like structures below N=60 and rotational bands above. The present study defines the limits of the deformed region around Aâ¼100 and indicates that the deformation of (97)Rb is essentially the same as that observed well inside the deformed region. It further highlights the power of the Coulomb-excitation technique for obtaining spectroscopic information far from stability. The (99)Rb case demonstrates the challenges of studies with very short-lived postaccelerated radioactive beams.
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Lineage 2 West Nile virus (WNV), previously found only in sub-Saharan Africa and Madagascar, was identified in Hungary in 2004 and has rapidly expanded in Europe in the past decade. Following a significant outbreak of West Nile fever with neurological cases caused by lineage 1 WNV in Romania in 1996, scattered cases have been recorded in the south-east of the country in each transmission season. Another outbreak, affecting a larger area and caused by lineage 2 WNV, was recorded in 2010. We analysed human sera from neuroinvasive West Nile fever cases and mosquitoes, sampled in south-eastern Romania between 2011 and 2013, for the presence of WNV genome, and obtained partial NS5 and envelope glycoprotein sequences. Human- and mosquito-derived WNV sequences were highly similar (99%) to Volgograd 2007 lineage 2 WNV and differed from isolates previously detected in central and southern Europe. WNV was detected in one pool of Culex pipiens s.l. males, documenting vertical transmission. Lineage 4 WNV, of unknown pathogenicity to mammals, was found in the amphibian-feeding mosquito Uranotaenia unguiculata from the Danube Delta. Our results present molecular evidence for the maintenance of the same isolates of Volgograd 2007-like lineage 2 WNV in south-eastern Romania between 2011 and 2013.
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Culicidae/virologia , Surtos de Doenças , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Genoma , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral , Reação em Cadeia da Polimerase em Tempo Real , Romênia/epidemiologia , Febre do Nilo Ocidental/sangue , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/classificação , Vírus do Nilo Ocidental/genéticaRESUMO
AIMS: To confirm, in a 26-week extension study, the sustained efficacy and safety of a fixed combination of insulin degludec and liraglutide (IDegLira) compared with either insulin degludec or liraglutide alone, in patients with type 2 diabetes. METHODS: Insulin-naïve adults with type 2 diabetes randomized to once-daily IDegLira, insulin degludec or liraglutide, in addition to metformin ± pioglitazone, continued their allocated treatment in this preplanned 26-week extension of the DUAL I trial. RESULTS: A total of 78.8% of patients (1311/1663) continued into the extension phase. The mean glycated haemoglobin (HbA1c) concentration at 52 weeks was reduced from baseline by 1.84% (20.2 mmol/mol) for the IDegLira group, 1.40% (15.3 mmol/mol) for the insulin degludec group and 1.21% (13.2 mmol/mol) for the liraglutide group. Of the patients on IDegLira, 78% achieved an HbA1c of <7% (53 mmol/mol) versus 63% of the patients on insulin degludec and 57% of those on liraglutide. The mean fasting plasma glucose concentration at the end of the trial was similar for IDegLira (5.7 mmol/l) and insulin degludec (6.0 mmol/l), but higher for liraglutide (7.3 mmol/l). At 52 weeks, the daily insulin dose was 37% lower with IDegLira (39 units) than with insulin degludec (62 units). IDegLira was associated with a significantly greater decrease in body weight (estimated treatment difference, -2.80 kg, p < 0.0001) and a 37% lower rate of hypoglycaemia compared with insulin degludec. Overall, all treatments were well tolerated and no new adverse events or tolerability issues were observed for IDegLira. CONCLUSIONS: These 12-month data, derived from a 26-week extension of the DUAL I trial, confirm the initial 26-week main phase results and the sustainability of the benefits of IDegLira compared with its components in glycaemic efficacy, safety and tolerability.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina de Ação Prolongada/administração & dosagem , Liraglutida/administração & dosagem , Idoso , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Jejum/sangue , Feminino , Hemoglobinas Glicadas/efeitos dos fármacos , Humanos , Hipoglicemia/induzido quimicamente , Masculino , Metformina/administração & dosagem , Pessoa de Meia-Idade , Pioglitazona , Tiazolidinedionas/administração & dosagem , Redução de Peso/efeitos dos fármacosRESUMO
We report on the first measurement of the fission barrier height in a heavy shell-stabilized nucleus. The fission barrier height of 254No is measured to be Bf=6.0±0.5 MeV at spin 15â and, by extrapolation, Bf=6.6±0.9 MeV at spin 0â. This information is deduced from the measured distribution of entry points in the excitation energy versus spin plane. The same measurement is performed for 220Th and only a lower limit of the fission barrier height can be determined: Bf(I)>8 MeV. Comparisons with theoretical fission barriers test theories that predict properties of superheavy elements.
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There is strong circumstantial evidence that certain heavy, unstable atomic nuclei are 'octupole deformed', that is, distorted into a pear shape. This contrasts with the more prevalent rugby-ball shape of nuclei with reflection-symmetric, quadrupole deformations. The elusive octupole deformed nuclei are of importance for nuclear structure theory, and also in searches for physics beyond the standard model; any measurable electric-dipole moment (a signature of the latter) is expected to be amplified in such nuclei. Here we determine electric octupole transition strengths (a direct measure of octupole correlations) for short-lived isotopes of radon and radium. Coulomb excitation experiments were performed using accelerated beams of heavy, radioactive ions. Our data on (220)Rn and (224)Ra show clear evidence for stronger octupole deformation in the latter. The results enable discrimination between differing theoretical approaches to octupole correlations, and help to constrain suitable candidates for experimental studies of atomic electric-dipole moments that might reveal extensions to the standard model.
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INTRODUCTION: Residents of Appalachia may benefit from oral cancer screening given the region's higher oral and pharyngeal cancer mortality rates. The current study examined the oral cancer screening behaviors and recent dental care (since dentists perform most screening examinations) of women from Ohio Appalachia. METHODS: Women from Ohio Appalachia were surveyed for the Community Awareness Resources Education (CARE) study, which was completed in 2006. A secondary aim of the CARE baseline survey was to examine oral cancer screening and dental care use among women from this region. Outcomes included whether women (n=477; cooperation rate = 71%) had ever had an oral cancer screening examination and when their most recent dental visit had occurred. Various demographic characteristics, health behaviors and psychosocial factors were examined as potential correlates. Analyses used multivariate logistic regression. RESULTS: Most women identified tobacco-related products as risk factors for oral cancer, but 43% of women did not know an early sign of oral cancer. Only 15% of women reported ever having had an oral cancer screening examination, with approximately 80% of these women indicating that a dentist had performed their most recent examination. Women were less likely to have reported a previous examination if they were from urban areas (OR=0.33, 95% CI: 0.13-0.85) or perceived a lower locus of health control (OR=0.94, 95% CI: 0.89-0.98). Women were more likely to have reported a previous examination if they had had a dental visit within the last year (OR=2.24, 95% CI: 1.03-4.88). Only 65% of women, however, indicated a dental visit within the last year. Women were more likely to have reported a recent dental visit if they were of a high socioeconomic status (OR=2.83, 95% CI: 1.58-5.06), had private health insurance (OR=2.20, 95% CI: 1.21-3.97) or had consumed alcohol in the last month (OR=2.03, 95% CI: 1.20-3.42). CONCLUSION: Oral cancer screening was not common among women from Ohio Appalachia, with many missed opportunities having occurred at dental visits. Education programs targeting dentists and other healthcare providers (given dental providers are lacking in some areas of Ohio Appalachia) about opportunistic oral cancer screening may help to improve screening in Appalachia. These programs should include information about populations at high risk for oral cancer (eg smokers) and how screening may be especially beneficial for them. Future research is needed to examine the acceptability of such education programs to healthcare providers in the Appalachian region and to explore why screening was less common among women living in urban areas of Ohio Appalachia.
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Assistência Odontológica/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Programas de Rastreamento/estatística & dados numéricos , Neoplasias Bucais/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adolescente , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Região dos Apalaches , Depressão/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Comportamentos Relacionados com a Saúde/etnologia , Humanos , Seguro Saúde/estatística & dados numéricos , Modelos Logísticos , Pessoa de Meia-Idade , Neoplasias Bucais/terapia , Ohio/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Fumar/epidemiologia , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
The neutron-rich nuclei 94,96Kr were studied via projectile Coulomb excitation at the REX-ISOLDE facility at CERN. Level energies of the first excited 2(+) states and their absolute E2 transition strengths to the ground state are determined and discussed in the context of the E(2(1)(+)) and B(E2;2(1)(+)â0(1)(+)) systematics of the krypton chain. Contrary to previously published results no sudden onset of deformation is observed. This experimental result is supported by a new proton-neutron interacting boson model calculation based on the constrained Hartree-Fock-Bogoliubov approach using the microscopic Gogny-D1M energy density functional.
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WHAT IS KNOWN AND OBJECTIVE: Warfarin, an oral anticoagulant, which has been in clinical use for over sixty years, remains a challenge for clinicians to utilize, given the multiplicity of items which can limit its efficacy. Our objective is to review the evidence and comment on whether INR control can be better than has been currently reported in various studies. COMMENT: The duration of time a patient's international normalized ratio (INR) is maintained within the therapeutic range (time in the therapeutic range, TTR) for his or her particular indication for the drug impacts the effectiveness and safety of warfarin therapy. Maintaining a therapeutic INR while on warfarin is difficult, and numerous studies employing various strategies confirm the challenge, but not the impossibility of achieving a TTR above 70%. WHAT IS NEW AND CONCLUSION: Maintaining a therapeutic INR requires a dedicated multi-faceted approach. With diligence, skill and various therapeutic strategies, a TTR >70% can be achieved.