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1.
Nurse Educ Pract ; 77: 103954, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38613983

RESUMO

AIM: The aim of this study is to further develop a preliminary framework into a model that can translate mechanisms into output and impact, based on the views of those working in practice and the relations between the mechanisms: a model that can inform practitioners and organizations on what has to be in place to shape a learning and innovating environment in nursing. BACKGROUND: A Learning and Innovation Network (LIN) is a network of healthcare professionals, students and education representatives who come together to be part of a nursing community to integrate education, research and practice to contribute to quality of care. In a previous study a preliminary framework was developed through a concept analysis based on publications. The preliminary framework describes input, throughput and output factors in a linear model that does not explain what the components entail in practice and how the components work together. DESIGN: Focus groups. METHODS: We designed a Theory of Change (ToC) in four phases. This was based on a focus group interview with lecturer practitioners (Phase 1); a first concept ToC based on thematic analysis of the focus group interview (Phase 2); three paired interviews where the ToC was presented to other lecturer practitioners to complement and verify the ToC model (Phase 3); and adjustment of the model based on the feedback of phase 3 (Phase 4). RESULTS: The developed ToC model describes important preconditions that have to be in place to start a LIN: a shared vision, a facilitating support system and a diversity of participants who are open to change. It describes the mechanisms by which a wide range of activities can lead to an improvement of the quality of care through collaboration between practice, education and research by working, learning, performing practice based research and implementing new methods together. CONCLUSION: This study gives a comprehensive overview of the concept of the 'Learning and Innovation Network' (LIN); how the activities in the LIN can lead to impact; and under what conditions. Previously published findings supported elements of the ToC model. The overarching ToC model and the detailed appendix offer a theoretical and practice-based model for practitioners, managers and policy makers.


Assuntos
Grupos Focais , Aprendizagem , Pesquisa Qualitativa , Humanos , Inovação Organizacional , Modelos Educacionais
2.
Nurse Educ Today ; 104: 104988, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34246837

RESUMO

BACKGROUND: Approximately 4 years ago a new concept of learning in practice called the 'Learning and Innovation Network (LIN)' was introduced in The Netherlands. To develop a definition of the LIN, to identify working elements of the LIN in order to provide a preliminary framework for evaluation, a concept analysis was conducted. METHOD: For the concept analysis, we adopted the method of Walker and Avant. We searched for relevant publications in the EBSCO host portal, grey literature and snowball searches, as well as Google internet searches and dictionary consults. RESULTS: Compared to other forms of workplace learning, the LIN is in the centre of the research, education and practice triangle. The most important attributes of the LIN are social learning, innovation, daily practice, reflection and co-production. Often described antecedents are societal developments, such as increasing complexity of work, and time and space to learn. Frequently identified consequences are an attractive workplace, advancements of expertise of care professionals, innovations that endorse daily practice, improvement of quality of care and the integration of education and practice. CONCLUSIONS: Based on the results of the concept analysis, we describe the LIN as 'a group of care professionals, students and an education representatives who come together in clinical practice and are all part of a learning and innovation community in nursing. They work together on practice-based projects in which they combine best practices, research evidence and client perspectives in order to innovate and improve quality of care and in which an integration of education, research and practice takes place'. We transferred the outcomes of the concept analysis to an input-throughput-output model that can be used as a preliminary framework for future research.


Assuntos
Bacharelado em Enfermagem , Aprendizagem , Formação de Conceito , Humanos , Países Baixos , Estudantes
3.
Surg Today ; 50(8): 872-880, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32016613

RESUMO

PURPOSE: The present study aimed to compare robotic-assisted versus laparoscopic distal pancreatic resection and enucleation for potentially benign pancreatic neoplasms. METHODS: Patients were retrieved from a prospectively maintained database. Demographic data, tumor types, and the perioperative outcomes were retrospectively analyzed. RESULTS: In a 10-year period, 75 patients (female, n = 44; male, n = 31; median age, 53 years [range, 9-84 years]) were identified. The majority of patients had pancreatic neuroendocrine neoplasms (n = 39, 52%) and cystic neoplasms (n = 23, 31%) with a median tumor size of 17 (3-60) mm. Nineteen (25.3%) patients underwent enucleation (robotic, n = 11; laparoscopic, n = 8) and 56 (74.7%) patients underwent distal pancreatic resection (robotic, n = 24; laparoscopic, n = 32), of those 48 (85%) underwent spleen-preserving procedures. Eight (10.7%) procedures had to be converted to open surgery. The rate of vessel preservation in distal pancreatectomy was significantly higher in robotic-assisted procedures (62.5% vs. 12.5%, p = 0.01). Twenty-six (34.6%) patients experienced postoperative complications (Clavien-Dindo grade > 3). Twenty (26.7%) patients developed a pancreatic fistula type B. There was no mortality. After a median follow-up period of 58 months (range 2-120 months), one patient (1.3%) developed local recurrence (glucagonoma) after enucleation, which was treated with a Whipple procedure. CONCLUSION: The robotic approach is comparably safe, but increases the rate of splenic vessel preservation and reduces the risk of conversion to open surgery.


Assuntos
Carcinoma Neuroendócrino/cirurgia , Laparoscopia/métodos , Pancreatectomia/métodos , Neoplasias Pancreáticas/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Fístula Pancreática/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Segurança , Baço , Adulto Jovem
4.
Phys Rev Lett ; 123(10): 102501, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31573317

RESUMO

An extensive, model-independent analysis of the nature of triaxial deformation in ^{76}Ge, a candidate for neutrinoless double-beta (0νßß) decay, was carried out following multistep Coulomb excitation. Shape parameters deduced on the basis of a rotational-invariant sum-rule analysis provided considerable insight into the underlying collectivity of the ground-state and γ bands. Both sequences were determined to be characterized by the same ß and γ deformation parameter values. In addition, compelling evidence for low-spin, rigid triaxial deformation in ^{76}Ge was obtained for the first time from the analysis of the statistical fluctuations of the quadrupole asymmetry deduced from the measured E2 matrix elements. These newly determined shape parameters are important input and constraints for calculations aimed at providing, with suitable accuracy, the nuclear matrix elements relevant to 0νßß.

5.
Phys Rev Lett ; 121(18): 182501, 2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30444390

RESUMO

We report the first observation of the ^{108}Xe→^{104}Te→^{100}Sn α-decay chain. The α emitters, ^{108}Xe [E_{α}=4.4(2) MeV, T_{1/2}=58_{-23}^{+106} µs] and ^{104}Te [E_{α}=4.9(2) MeV, T_{1/2}<18 ns], decaying into doubly magic ^{100}Sn were produced using a fusion-evaporation reaction ^{54}Fe(^{58}Ni,4n)^{108}Xe, and identified with a recoil mass separator and an implantation-decay correlation technique. This is the first time α radioactivity has been observed to a heavy self-conjugate nucleus. A previous benchmark for study of this fundamental decay mode has been the decay of ^{212}Po into doubly magic ^{208}Pb. Enhanced proton-neutron interactions in the N=Z parent nuclei may result in superallowed α decays with reduced α-decay widths significantly greater than that for ^{212}Po. From the decay chain, we deduce that the α-reduced width for ^{108}Xe or ^{104}Te is more than a factor of 5 larger than that for ^{212}Po.

6.
World J Surg ; 42(5): 1440-1447, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29075857

RESUMO

BACKGROUND: Radiological tumor size of non-functioning pancreatic neuroendocrine neoplasms (Nf-pNENs) associated with multiple endocrine neoplasia type 1 (MEN1) is a crucial parameter to indicate surgery. The aim of this study was to compare radiological size (RS) and pathologic size (PS) of MEN1 associated with pNENs. METHODS: Prospectively collected data of MEN1 patients who underwent pancreatic resections for pNENs were retrospectively analyzed. RS was defined as the largest tumor diameter measured on endoscopic ultrasound (EUS), magnetic resonance imaging (MRI) or computed tomography (CT). PS was defined as the largest tumor diameter on pathological analysis. Student's t test and linear regression analysis were used to compare the median RS and PS. p < 0.05 was considered significant. RESULTS: Forty-four patients with a median age of 37 (range 10-68) years underwent primary pancreatic resections for pNENs. Overall, the median RS (20 mm, range 3-100 mm) was significantly larger than the PS (13 mm, range 4-110 mm) (p = 0.001). In patients with pNENs < 20 mm (n = 27), the size difference (median RS 15 mm vs PS 12 mm) was also significant (p = 0.003). However, the only modality that significantly overestimated the PS was EUS (median RS 14 mm vs 11 mm; p = 0.0002). RS overestimated the PS in 21 patients (21 of 27 patients, 78%). Five of 11 patients (12%) with a Nf-pNEN and a RS > 20 mm had in reality a PS < 20 mm. MRI was the imaging technique that best correlated with PS in the total cohort (r = 0.8; p < 0.0001), whereas EUS was the best correlating imaging tool in pNENs < 20 mm (r = 0.5; p = 0.0001). CONCLUSION: Preoperative imaging, especially EUS, frequently overestimates the size of MEN1-pNENs, especially those with a PS < 20 mm. This should be considered when indicating surgery in MEN1 patients with small Nf-pNENs.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1/diagnóstico por imagem , Tumores Neuroendócrinos/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Cuidados Pré-Operatórios , Adolescente , Adulto , Idoso , Criança , Endossonografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/patologia , Neoplasia Endócrina Múltipla Tipo 1/cirurgia , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
7.
J Dent Res ; 95(13): 1464-1471, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27655623

RESUMO

The authors evaluated the association of reduced bone stiffness of the calcaneus with clinical attachment loss (CAL) and tooth loss. The authors analyzed data from 4,678 subjects (2,384 women), aged 20 to 88 y, from the second follow-up of the population-based Study of Health in Pomerania (SHIP-2) and the baseline examination of the SHIP-Trend cohort. Bone stiffness, characterized by the stiffness index (SI) and the osteoporotic fracture risk (OFR), was assessed by quantitative ultrasound of the heel. SI and OFR were significantly associated with the mean CAL in women. While 1) the SI showed a significant association with the mean CAL and 2) the OFR with the median number of teeth in just the postmenopausal women, the OFR showed a significant association with mean CAL for both pre- and postmenopausal women. In postmenopausal women, a 10-unit increase in the SI was associated with a decrease in the mean CAL of 0.05 mm (95% confidence interval [CI]: -0.10 to 0.00; P = 0.046). Moreover, the adjusted median number of teeth was 21.4 (95% CI: 20.9 to 21.9) among the postmenopausal women with a low OFR, while it was 19.1 (95% CI: 17.8 to 20.3; P = 0.001) among the postmenopausal women with a high OFR. For the premenopausal women with a low OFR, the mean CAL was 1.60 mm (95% CI: 1.53 to 1.66), while for the premenopausal women with a high OFR, it was 2.24 mm (95% CI: 1.78 to 2.69; P = 0.006). Reduced bone stiffness was associated with clinical attachment and tooth loss in women but not in men.


Assuntos
Densidade Óssea , Calcâneo/diagnóstico por imagem , Calcâneo/patologia , Perda da Inserção Periodontal/epidemiologia , Perda de Dente/epidemiologia , Absorciometria de Fóton , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha/epidemiologia , Humanos , Pessoa de Meia-Idade , Fatores de Risco
8.
Phys Rev Lett ; 116(11): 112503, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-27035298

RESUMO

The neutron-rich nucleus ^{144}Ba (t_{1/2}=11.5 s) is expected to exhibit some of the strongest octupole correlations among nuclei with mass numbers A less than 200. Until now, indirect evidence for such strong correlations has been inferred from observations such as enhanced E1 transitions and interleaving positive- and negative-parity levels in the ground-state band. In this experiment, the octupole strength was measured directly by sub-barrier, multistep Coulomb excitation of a post-accelerated 650-MeV ^{144}Ba beam on a 1.0-mg/cm^{2} ^{208}Pb target. The measured value of the matrix element, ⟨3_{1}^{-}∥M(E3)∥0_{1}^{+}⟩=0.65(+17/-23) eb^{3/2}, corresponds to a reduced B(E3) transition probability of 48(+25/-34) W.u. This result represents an unambiguous determination of the octupole collectivity, is larger than any available theoretical prediction, and is consistent with octupole deformation.

11.
Phys Rev Lett ; 115(13): 132502, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26451549

RESUMO

Two isomers decaying by electromagnetic transitions with half-lives of 4.7(1.1) and 247(73) µs have been discovered in the heavy ^{254}Rf nucleus. The observation of the shorter-lived isomer was made possible by a novel application of a digital data acquisition system. The isomers were interpreted as the K^{π}=8^{-}, ν^{2}(7/2^{+}[624],9/2^{-}[734]) two-quasineutron and the K^{π}=16^{+}, 8^{-}ν^{2}(7/2^{+}[624],9/2^{-}[734])⊗8^{-}π^{2}(7/2^{-}[514],9/2^{+}[624]) four-quasiparticle configurations, respectively. Surprisingly, the lifetime of the two-quasiparticle isomer is more than 4 orders of magnitude shorter than what has been observed for analogous isomers in the lighter N=150 isotones. The four-quasiparticle isomer is longer lived than the ^{254}Rf ground state that decays exclusively by spontaneous fission with a half-life of 23.2(1.1) µs. The absence of sizable fission branches from either of the isomers implies unprecedented fission hindrance relative to the ground state.

12.
BMJ ; 350: h418, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25670715

RESUMO

OBJECTIVES: To evaluate the outcome of drowned children with cardiac arrest and hypothermia, and to determine distinct criteria for termination of cardiopulmonary resuscitation in drowned children with hypothermia and absence of spontaneous circulation. DESIGN: Nationwide retrospective cohort study. SETTING: Emergency departments and paediatric intensive care units of the eight university medical centres in the Netherlands. PARTICIPANTS: Children aged up to 16 with cardiac arrest and hypothermia after drowning, who presented at emergency departments and/or were admitted to intensive care. MAIN OUTCOME MEASURE: Survival and neurological outcome one year after the drowning incident. Poor outcome was defined as death or survival in a vegetative state or with severe neurological disability (paediatric cerebral performance category (PCPC) ≥ 4). RESULTS: From 1993 to 2012, 160 children presented with cardiac arrest and hypothermia after drowning. In 98 (61%) of these children resuscitation was performed for more than 30 minutes (98/160, median duration 60 minutes), of whom 87 (89%) died (95% confidence interval 83% to 95%; 87/98). Eleven of the 98 children survived (11%, 5% to 17%), but all had a PCPC score ≥ 4. In the 62 (39%) children who did not require prolonged resuscitation, 17 (27%, 16% to 38%) survived with a PCPC score ≤ 3 after one year: 10 (6%) had a good neurological outcome (score 1), five (3%) had mild neurological disability (score 2), and two (1%) had moderate neurological disability (score 3). From the original 160 children, only 44 were alive at one year with any outcome. CONCLUSIONS: Drowned children in whom return of spontaneous circulation is not achieved within 30 minutes of advanced life support have an extremely poor outcome. Good neurological outcome is more likely when spontaneous circulation returns within 30 minutes of advanced life support, especially when the drowning incident occurs in winter. These findings question the therapeutic value of resuscitation beyond 30 minutes in drowned children with cardiac arrest and hypothermia.


Assuntos
Reanimação Cardiopulmonar , Afogamento , Parada Cardíaca/terapia , Hipotermia/terapia , Afogamento Iminente/terapia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Parada Cardíaca/etiologia , Humanos , Hipotermia/etiologia , Lactente , Masculino , Países Baixos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Suspensão de Tratamento
13.
Phys Rev Lett ; 112(19): 192701, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24877935

RESUMO

The interaction between neutron-rich nuclei plays an important role for understanding the reaction mechanism of the fusion process as well as for the energy production through pycnonuclear reactions in the crust of neutron stars. We have performed the first measurements of the total fusion cross sections in the systems (10,14,15)C+(12)C using a new active target-detector system. In the energy region accessible with existing radioactive beams, a good agreement between the experimental and theoretical cross sections is observed. This gives confidence in our ability to calculate fusion cross sections for systems which are outside the range of today's radioactive beam facilities.

14.
Phys Rev Lett ; 112(15): 152701, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24785033

RESUMO

The 1809-keV γ ray from the decay of (26)Al(g) is an important target for γ-ray astronomy. In the convective C/Ne burning shell of massive presupernova stars, the (23)Na(α,p)(26)Mg reaction directly influences the production of (26)Al. We have performed a direct measurement of the (23)Na(α,p)(26)Mg reaction cross section at the appropriate astrophysically important energies. The stellar rate calculated in the present work is larger than the recommended rate by nearly a factor of 40 and could strongly affect the production of (26)Al in massive stars.

15.
Phys Rev Lett ; 112(15): 152702, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24785034

RESUMO

We have studied the fission-neutron emission competition in highly excited (274)Hs (Z=108) (where the fission barrier is due to shell effects) formed by a hot fusion reaction. Matching cross bombardments ((26)Mg+(248)Cm and (25)Mg+(248)Cm) were used to identify the properties of first chance fission of (274)Hs. A Harding-Farley analysis of the fission neutrons emitted in the (25)Mg,26+(248)Cm was performed to identify the prescission and postscission components of the neutron multiplicities in each system. (Γn/Γt) for the first chance fission of (274)Hs (E*=63 MeV) is 0.89±0.13; i.e., ∼90% of the highly excited nuclei survive. The high value of that survival probability is due to dissipative effects during deexcitation. A proper description of the survival probabilities of excited superheavy nuclei formed in hot fusion reactions requires consideration of both dynamic and static (shell-related) effects.

16.
Phys Rev Lett ; 112(11): 112503, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24702356

RESUMO

Excited states in the neutron-rich N = 38, 36 nuclei (60)Ti and (58)Ti were populated in nucleon-removal reactions from (61)V projectiles at 90 MeV/nucleon. The γ-ray transitions from such states in these Ti isotopes were detected with the advanced γ-ray tracking array GRETINA and were corrected event by event for large Doppler shifts (v/c ∼ 0.4) using the γ-ray interaction points deduced from online signal decomposition. The new data indicate that a steep decrease in quadrupole collectivity occurs when moving from neutron-rich N = 36, 38 Fe and Cr toward the Ti and Ca isotones. In fact, (58,60)Ti provide some of the most neutron-rich benchmarks accessible today for calculations attempting to determine the structure of the potentially doubly magic nucleus (60)Ca.

17.
Gesundheitswesen ; 76(4): 237-40, 2014 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-24671894

RESUMO

It is strongly recommended to establish mental health laws in every state. By these laws, outpatient services have to be dedicated to avoiding involuntary hospitalisations. Community mental health systems need to be enabled to supply low threshold, immediate care services, if necessary at home (home treatment resp. assertive community treatment). To this end, the role of sociopsychiatric services in service coordination has to be strengthened and comprehensive community mental health organisations have to be established in every city or county. At state level, Councils on Mental Health need to be implemented by state government, mental health reporting, especially on rates of involuntary hospitalisations (by federal as well as state law) has to be established and visiting committees need to extend their scope to all institutions and services that play a role in prevention or aftercare of involuntary hospitalisation.


Assuntos
Internação Compulsória de Doente Mental/legislação & jurisprudência , Internação Compulsória de Doente Mental/normas , Serviços Comunitários de Saúde Mental/legislação & jurisprudência , Serviços Comunitários de Saúde Mental/normas , Transtornos Mentais/terapia , Serviços de Saúde Mental/legislação & jurisprudência , Serviços de Saúde Mental/normas , Alemanha , Humanos
18.
Vet Microbiol ; 171(3-4): 364-7, 2014 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-24495740

RESUMO

In the Netherlands, livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) has been found in pigs, veal calves, horses and poultry. However, little is known about its prevalence in healthy dairy cattle. Recently, a new mec gene, called mecC, has been found in methicillin-resistant S. aureus (MRSA) isolates from humans and animals in several countries. The objective of our pilot study was to investigate the prevalence of MRSA (mecA and mecC) in dairy cows at a large slaughterhouse. Samples from the skin between the udder and hind leg were taken from 411 cows. The samples were incubated in Mueller-Hinton enrichment broth with 6.5% NaCl, followed by selective enrichment and plated onto Columbia agar with 5% sheep blood, Brilliance MRSA 2 agar and Baird-Parker agar. Suspected colonies were tested by PCR for a S. aureus specific DNA fragment, the mecA and mecC genes and the Panton-Valentine leucotoxin (PVL) genes. All MRSA isolates and methicillin-susceptible S. aureus (MSSA) isolates were typed by spa typing and MLVA typing. Sixteen of 411 (3.9%) cows, all originating from different farms, were found to be MRSA positive and this prevalence is lower than in Dutch pigs, veal calves and broilers. All MRSA isolates belonging to livestock-associated MLVA complex 398, were PVL-negative and spa type t011 predominated. MSSA isolates (n=39) were of many different MLVA types and spa type t543 was found most often. Four MSSA isolates belonging to MLVA clonal complex 398 and spa types t011 (n=2), t108 and t034 were isolated from different MRSA-negative animals. In conclusion, the prevalence of MRSA in dairy cows was low and isolates carrying the mecC gene were not found, indicating that it is absent or has a low prevalence (<0.73%) in Dutch dairy cows.


Assuntos
Proteínas de Bactérias/genética , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/veterinária , Matadouros , Animais , Técnicas de Tipagem Bacteriana/veterinária , Bovinos , Indústria de Laticínios/métodos , Feminino , Países Baixos/epidemiologia , Proteínas de Ligação às Penicilinas , Reação em Cadeia da Polimerase/veterinária , Prevalência , Pele/microbiologia , Infecções Estafilocócicas/epidemiologia
19.
Nature ; 497(7448): 199-204, 2013 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-23657348

RESUMO

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.

20.
Phys Rev Lett ; 108(6): 062701, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22401060

RESUMO

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)(+)→0(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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