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1.
Nature ; 569(7754): 53-58, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043730

RESUMO

Nuclear magic numbers correspond to fully occupied energy shells of protons or neutrons inside atomic nuclei. Doubly magic nuclei, with magic numbers for both protons and neutrons, are spherical and extremely rare across the nuclear landscape. Although the sequence of magic numbers is well established for stable nuclei, experimental evidence has revealed modifications for nuclei with a large asymmetry between proton and neutron numbers. Here we provide a spectroscopic study of the doubly magic nucleus 78Ni, which contains fourteen neutrons more than the heaviest stable nickel isotope. We provide direct evidence of its doubly magic nature, which is also predicted by ab initio calculations based on chiral effective-field theory interactions and the quasi-particle random-phase approximation. Our results also indicate the breakdown of the neutron magic number 50 and proton magic number 28 beyond this stronghold, caused by a competing deformed structure. State-of-the-art phenomenological shell-model calculations reproduce this shape coexistence, predicting a rapid transition from spherical to deformed ground states, with 78Ni as the turning point.

2.
Phys Rev Lett ; 130(17): 172501, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172241

RESUMO

We report on the first proton-induced single proton- and neutron-removal reactions from the neutron-deficient ^{14}O nucleus with large Fermi-surface asymmetry S_{n}-S_{p}=18.6 MeV at ∼100 MeV/nucleon, a widely used energy regime for rare-isotope studies. The measured inclusive cross sections and parallel momentum distributions of the ^{13}N and ^{13}O residues are compared to the state-of-the-art reaction models, with nuclear structure inputs from many-body shell-model calculations. Our results provide the first quantitative contributions of multiple reaction mechanisms including the quasifree knockout, inelastic scattering, and nucleon transfer processes. It is shown that the inelastic scattering and nucleon transfer, usually neglected at such energy regime, contribute about 50% and 30% to the loosely bound proton and deeply bound neutron removal, respectively. These multiple reaction mechanisms should be considered in analyses of inclusive one-nucleon removal cross sections measured at intermediate energies for quantitative investigation of single-particle strengths and correlations in atomic nuclei.

3.
Phys Rev Lett ; 131(21): 212501, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38072612

RESUMO

The cluster structure of the neutron-rich isotope ^{10}Be has been probed via the (p,pα) reaction at 150 MeV/nucleon in inverse kinematics and in quasifree conditions. The populated states of ^{6}He residues were investigated through missing mass spectroscopy. The triple differential cross section for the ground-state transition was extracted for quasifree angle pairs (θ_{p},θ_{α}) and compared to distorted-wave impulse approximation reaction calculations performed in a microscopic framework using successively the Tohsaki-Horiuchi-Schuck-Röpke product wave function and the wave function deduced from antisymmetrized molecular dynamics calculations. The remarkable agreement between calculated and measured cross sections in both shape and magnitude validates the molecular structure description of the ^{10}Be ground-state, configured as an α-α core with two valence neutrons occupying π-type molecular orbitals.

4.
Phys Rev Lett ; 129(26): 262501, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36608181

RESUMO

The one-neutron knockout from ^{52}Ca in inverse kinematics onto a proton target was performed at ∼230 MeV/nucleon combined with prompt γ spectroscopy. Exclusive quasifree scattering cross sections to bound states in ^{51}Ca and the momentum distributions corresponding to the removal of 1f_{7/2} and 2p_{3/2} neutrons were measured. The cross sections, interpreted within the distorted-wave impulse approximation reaction framework, are consistent with a shell closure at the neutron number N=32, found as strong as at N=28 and N=34 in Ca isotopes from the same observables. The analysis of the momentum distributions leads to a difference of the root-mean-square radii of the neutron 1f_{7/2} and 2p_{3/2} orbitals of 0.61(23) fm, in agreement with the modified-shell-model prediction of 0.7 fm suggesting that the large root-mean-square radius of the 2p_{3/2} orbital in neutron-rich Ca isotopes is responsible for the unexpected linear increase of the charge radius with the neutron number.

5.
Morphologie ; 106(352): 43-45, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33358105

RESUMO

The ansa cervicalis (AC) is part of the cervical plexus and is formed by the ventral rami of spinal nerves C1-C3. It is usually formed by two roots that run parallel to each other and then form a loop anterior to the internal jugular vein. Herein, we report a rare case where the AC was found deep to the internal carotid artery and common carotid artery and had sympathetic contributions.


Assuntos
Plexo Cervical , Nervos Espinhais , Artéria Carótida Interna , Veias Jugulares/diagnóstico por imagem
6.
Phys Rev Lett ; 126(25): 252501, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34241497

RESUMO

Direct proton-knockout reactions of ^{55}Sc at ∼220 MeV/nucleon were studied at the RIKEN Radioactive Isotope Beam Factory. Populated states of ^{54}Ca were investigated through γ-ray and invariant-mass spectroscopy. Level energies were calculated from the nuclear shell model employing a phenomenological internucleon interaction. Theoretical cross sections to states were calculated from distorted-wave impulse approximation estimates multiplied by the shell model spectroscopic factors, which describe the wave function overlap of the ^{55}Sc ground state with states in ^{54}Ca. Despite the calculations showing a significant amplitude of excited neutron configurations in the ground-state of ^{55}Sc, valence proton removals populated predominantly the ground state of ^{54}Ca. This counterintuitive result is attributed to pairing effects leading to a dominance of the ground-state spectroscopic factor. Owing to the ubiquity of the pairing interaction, this argument should be generally applicable to direct knockout reactions from odd-even to even-even nuclei.

7.
Phys Rev Lett ; 126(8): 082501, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33709737

RESUMO

A kinematically complete quasifree (p,pn) experiment in inverse kinematics was performed to study the structure of the Borromean nucleus ^{17}B, which had long been considered to have a neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for 1s_{1/2} and 0d_{5/2} orbitals, and a surprisingly small percentage of 9(2)% was determined for 1s_{1/2}. Our finding of such a small 1s_{1/2} component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in ^{17}B. The present work gives the smallest s- or p-orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of s or p orbitals is not a prerequisite for the occurrence of a neutron halo.

8.
Br J Surg ; 107(6): 632-635, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32246473

RESUMO

Probe electrospray ionization mass spectrometry (PESI-MS) is an ambient ionization-based mass spectrometry method that surpasses the original electrospray ionization technique in features such as the rapidity of analysis, simplicity of the equipment and procedure, and lower cost. This study found that the PESI-MS system with machine learning has the potential to establish a lipid-based diagnosis of breast cancer with higher accuracy, using a simpler approach. Rapid mass spectrometry for breast cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/diagnóstico , Mama/metabolismo , Metabolismo dos Lipídeos , Espectrometria de Massas por Ionização por Electrospray , Biópsia , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Sensibilidade e Especificidade
9.
Phys Rev Lett ; 125(25): 252501, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33416401

RESUMO

The formation of a dineutron in the ^{11}Li nucleus is found to be localized to the surface region. The experiment measured the intrinsic momentum of the struck neutron in ^{11}Li via the (p,pn) knockout reaction at 246 MeV/nucleon. The correlation angle between the two neutrons is, for the first time, measured as a function of the intrinsic neutron momentum. A comparison with reaction calculations reveals the localization of the dineutron at r∼3.6 fm. The results also support the density dependence of dineutron formation as deduced from Hartree-Fock-Bogoliubov calculations for nuclear matter.

10.
Phys Rev Lett ; 124(21): 212502, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32530645

RESUMO

The structure of a neutron-rich ^{25}F nucleus is investigated by a quasifree (p,2p) knockout reaction at 270A MeV in inverse kinematics. The sum of spectroscopic factors of π0d_{5/2} orbital is found to be 1.0±0.3. However, the spectroscopic factor with residual ^{24}O nucleus being in the ground state is found to be only 0.36±0.13, while those in the excited state is 0.65±0.25. The result shows that the ^{24}O core of ^{25}F nucleus significantly differs from a free ^{24}O nucleus, and the core consists of ∼35% ^{24}O_{g.s.}. and ∼65% excited ^{24}O. The result may infer that the addition of the 0d_{5/2} proton considerably changes neutron structure in ^{25}F from that in ^{24}O, which could be a possible mechanism responsible for the oxygen dripline anomaly.

11.
Phys Rev Lett ; 124(21): 212503, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32530691

RESUMO

The heaviest bound isotope of boron ^{19}B has been investigated using exclusive measurements of its Coulomb dissociation, into ^{17}B and two neutrons, in collisions with Pb at 220 MeV/nucleon. Enhanced electric dipole (E1) strength is observed just above the two-neutron decay threshold with an integrated E1 strength of B(E1)=1.64±0.06(stat)±0.12(sys) e^{2} fm^{2} for relative energies below 6 MeV. This feature, known as a soft E1 excitation, provides the first firm evidence that ^{19}B has a prominent two-neutron halo. Three-body calculations that reproduce the energy spectrum indicate that the valence neutrons have a significant s-wave configuration and exhibit a dineutronlike correlation.

12.
Phys Rev Lett ; 123(14): 142501, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31702209

RESUMO

Exclusive cross sections and momentum distributions have been measured for quasifree one-neutron knockout reactions from a ^{54}Ca beam striking on a liquid hydrogen target at ∼200 MeV/u. A significantly larger cross section to the p_{3/2} state compared to the f_{5/2} state observed in the excitation of ^{53}Ca provides direct evidence for the nature of the N=34 shell closure. This finding corroborates the arising of a new shell closure in neutron-rich calcium isotopes. The distorted-wave impulse approximation reaction formalism with shell model calculations using the effective GXPF1Bs interaction and ab initio calculations concur our experimental findings. Obtained transverse and parallel momentum distributions demonstrate the sensitivity of quasifree one-neutron knockout in inverse kinematics on a thick liquid hydrogen target with the reaction vertex reconstructed to final state spin-parity assignments.

15.
Int J Clin Oncol ; 22(4): 793-800, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28386794

RESUMO

BACKGROUND: Cancer chemotherapy is associated with a variety of side effects/adverse events. It is very important that patients adhere to the planned chemotherapy regimen, which necessitates a minimum of side effects and that these side effects be kept under control. We have investigated patients' concerns and symptoms during chemotherapy with the aim to seek solutions that will improve patients' quality of life during chemotherapy. METHODS: Forty-nine patients with malignant diseases on parenteral antineoplastic agents were sequentially enrolled in this study. These patients completed a questionnaire consisting of 42 items related to non-physical concerns and 52 items of physical symptoms related to chemotherapy. Each patient was also asked to select the three items among these 94 items which affected him/her the most. RESULTS: The median age of the cancer patients was 62 years and the male-to-female ratio was 18:31. Among the non-physical concerns, the most frequently chosen concern was 'affects my family or partner,' followed by anxiety related to treatment. Regarding the physical symptoms, the most frequent complaints were fatigue, alopecia and constipation, while the most troublesome symptoms were nausea, poor taste and paresthesia. Overall, the most frequently expressed concerns were 'affects my family or partner' and anxiety related to treatment. Male patients suffered most from fever, fatigue and nausea, and female patients complained more of poor taste and gastrointestinal problems. CONCLUSION: Patient perceptions of adverse events associated with cancer chemotherapy apparently have changed from physical symptoms to non-physical concerns. In our patient cohort 'affects my family or partner' was the most important concern. One important point to note is that female patients often complained of poor taste because this meant they were unable to cook well.


Assuntos
Antineoplásicos/efeitos adversos , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Alopecia/induzido quimicamente , Antineoplásicos/uso terapêutico , Ansiedade , Fadiga/induzido quimicamente , Feminino , Gastroenteropatias/induzido quimicamente , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Qualidade de Vida , Inquéritos e Questionários
16.
Epidemiol Infect ; 143(4): 864-72, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25703404

RESUMO

Streptococcal toxic shock syndrome (STSS) is a severe invasive infection characterized by the sudden onset of shock, multi-organ failure, and high mortality. In Japan, appropriate notification measures based on the Infectious Disease Control law are mandatory for cases of STSS caused by ß-haemolytic streptococcus. STSS is mainly caused by group A streptococcus (GAS). Although an average of 60-70 cases of GAS-induced STSS are reported annually, 143 cases were recorded in 2011. To determine the reason behind this marked increase, we characterized the emm genotype of 249 GAS isolates from STSS patients in Japan from 2010 to 2012 and performed antimicrobial susceptibility testing. The predominant genotype was found to be emm1, followed by emm89, emm12, emm28, emm3, and emm90. These six genotypes constituted more than 90% of the STSS isolates. The number of emm1, emm89, emm12, and emm28 isolates increased concomitantly with the increase in the total number of STSS cases. In particular, the number of mefA-positive emm1 isolates has escalated since 2011. Thus, the increase in the incidence of STSS can be attributed to an increase in the number of cases associated with specific genotypes.


Assuntos
Choque Séptico/epidemiologia , Infecções Estreptocócicas/epidemiologia , Streptococcus pyogenes , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Clindamicina/farmacologia , Farmacorresistência Bacteriana/genética , Eritromicina/farmacologia , Feminino , Genótipo , Humanos , Lactente , Japão/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Choque Séptico/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus pyogenes/genética , Streptococcus pyogenes/isolamento & purificação , Adulto Jovem
17.
Acta Ortop Mex ; 37(4): 227-323, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38373733

RESUMO

The study intended to evaluate the incidence and evolution of sacroiliac joint dysfunction (SIJD). To reach 50 patients with SIJD diagnosis, 192 patients with low back pain and failure in conservative approach were consecutively examined (26% incidence). Initially patients underwent intra-articular (IA) corticosteroid sacroiliac joint (SIJ) block followed, if necessary, by cooled SIJ radiofrequency or referred to surgical intervention, in order of complexity. From the 50 patients submitted to IA SI block, 41 (82%) referred pain and quality of life improvement and lesser rescue analgesics consumption for 25 weeks. The block induced a prompt onset of pain relief and there was a drop in mean pain score from 8 to 2 cm (p < 0.001) maintained up to 25 weeks. Rescue analgesic consumption also significantly dropped (p < 0.05). However, nine patients (18%) did not refer long lasting improvement in the third week evaluation and underwent cooled radiofrequency. From this population of nine, seven were successful (78%) while two were recommended surgery. In view of the 50 patients, 82% were comfortable after IA block, 18% were submitted to radiofrequency, with a success rate of 78%. The final incidence of surgery suggestion was 4%.


El estudio pretende evaluar la incidencia y evolución de la disfunción de la articulación sacroilíaca (DASI). Para llegar a 50 pacientes con diagnóstico de DASI, se examinaron consecutivamente 192 pacientes con dolor lumbar y fracaso en el abordaje conservador (26% de incidencia). Inicialmente, los pacientes se sometieron a un bloqueo de la articulación sacroilíaca (ASI) con corticosteroides intraarticulares (IA) seguido, si era necesario, de radiofrecuencia ASI enfriada o remitidos a una intervención quirúrgica, en orden de complejidad. De los 50 pacientes sometidos al bloqueo IA SI, 41 (82%) refirieron mejoría del dolor y de la calidad de vida y menor consumo de analgésicos de rescate durante 25 semanas. El bloqueo indujo un rápido inicio del alivio del dolor y hubo una caída en la puntuación media del dolor de 8 a 2 cm (p < 0.001) mantenida hasta 25 semanas. El consumo de analgésicos de rescate también disminuyó significativamente (p < 0.05). Sin embargo, nueve pacientes (18%) no refirieron una mejoría duradera en la evaluación de la tercera semana y se sometieron a radiofrecuencia fría. De esta población de nueve, siete tuvieron éxito (78%), mientras que a dos se les recomendó cirugía. De los 50 pacientes, 82% se sintió cómodo después del bloqueo IA, 18% fue sometido a radiofrecuencia, con una tasa de éxito de 78%. La incidencia final de sugerencia de cirugía fue de 4%.


Assuntos
Artropatias , Dor Lombar , Humanos , Dor Lombar/epidemiologia , Dor Lombar/etiologia , Dor Lombar/terapia , Articulação Sacroilíaca/cirurgia , Brasil , Qualidade de Vida
18.
Br J Cancer ; 107(1): 31-6, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22617130

RESUMO

BACKGROUND: A combination of S-1 and cisplatin has been shown to be effective with acceptable safety for the first-line treatment of far-advanced gastric cancer in Japan. This is the first randomised phase II trial to compare S-1+paclitaxel with S-1+cisplatin in this setting. METHODS: Patients with unresectable and/or recurrent advanced gastric cancer were randomly assigned to receive one of the two regimens: S-1 (40 mg m(-2) twice daily) on days 1-14 plus paclitaxel (60 mg m(-2)) on days 1, 8, and 15 of a 4-week cycle (S-1+paclitaxel) or S-1 (40 mg m(-2) twice daily) on days 1-21 plus cisplatin (60 mg m(-2)) on day 8 of a 5-week cycle (S-1+cisplatin). The primary end point was the response rate (RR). Secondary end points included progression-free survival (PFS), overall survival (OS), and safety. RESULTS: A total of 83 patients were eligible for safety and efficacy analyses. In the S-1+paclitaxel and S-1+cisplatin groups, RRs (52.3% vs 48.7%; P=0.74) and median PFS (9 vs 6 months; P=0.50) were similar. The median OS was similar in the S-1+paclitaxel and S-1+cisplatin groups (16 vs 17 months; P=0.84). The incidence of grade 3 or higher haematological toxicity was 19.0% with S-1+paclitaxel and 19.5% with S-1+cisplatin. The incidence of grade 3 or higher non-haematological toxicity was 14.2% with S-1+paclitaxel and 17.1% with S-1+cisplatin. CONCLUSION: S-1+paclitaxel was suggested to be a feasible and effective non-platinum-based regimen for chemotherapy in patients with advanced gastric cancer. Our results should be confirmed in multicenter, phase III-controlled clinical trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Ácido Oxônico/administração & dosagem , Paclitaxel/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Tegafur/administração & dosagem , Intervalo Livre de Doença , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/mortalidade
19.
Front Pharmacol ; 13: 744916, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222016

RESUMO

Background: Proper management of adverse events is crucial for the safe and effective implementation of anticancer drug treatment. Showa University Hospital uses our interview sheet (assessment and risk control [ARC] sheet) for the accurate evaluation of adverse events. On the day of anticancer drug treatment, a nurse conducts a face-to-face interview. As a feature of the ARC sheet, by separately describing the symptoms the day before treatment and the day of treatment and sharing the information on the medical record, it is possible to clearly determine the status of adverse events. In this study, we hypothesized that the usefulness and points for improvement of the ARC sheet would be clarified by using and evaluating a patient questionnaire. Methods: This study included 174 patients (144 at Showa University Hospital (Hatanodai Hospital) and 30 at Showa University Koto Toyosu Hospital (Toyosu Hospital) who underwent pre-examination interviews by nurses and received cancer chemotherapy at the outpatient center of Hatanodai and Toyosu Hospital. In the questionnaire survey, the ARC sheet's content and quality, respondents' satisfaction, structural strengths, and points for improvement were evaluated on a five-point scale. Results: The patient questionnaire received responses from 160 participants, including the ARC sheet use group (132 people) and the non-use group (28 people). Unlike the ARC sheet non-use group, the ARC sheet use group recognized that the sheet was useful to understand the adverse events of aphthous ulcers (p = 0.017) and dysgeusia (p = 0.006). In the satisfaction survey questionnaire, there was a high sense of security in the pre-examination interviews by nurses using the ARC sheet. Conclusions: The ARC sheet is considered an effective tool for comprehensively evaluating adverse events. Pre-examination interviews by nurses using ARC sheets accurately determined the adverse events experienced by patients with anxiety and tension due to confrontation with physicians.

20.
Nanotechnology ; 22(36): 365305, 2011 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-21841219

RESUMO

A systematic study of the kinetics of axial Ni silicidation of as-grown and oxidized Si nanowires (SiNWs) with different crystallographic orientations and core diameters ranging from ∼ 10 to 100 nm is presented. For temperatures between 300 and 440 °C the length of the total axial silicide intrusion varies with the square root of time, which provides clear evidence that the rate limiting step is diffusion of Ni through the growing silicide phase(s). A retardation of Ni-silicide formation for oxidized SiNWs is found, indicative of a stress induced lowering of the diffusion coefficients. Extrapolated growth constants indicate that the Ni flux through the silicided NW is dominated by surface diffusion, which is consistent with an inverse square root dependence of the silicide length on the NW diameter as observed for (111) orientated SiNWs. In situ TEM silicidation experiments show that NiSi(2) is the first forming phase for as-grown and oxidized SiNWs. The silicide-SiNW interface is thereby atomically abrupt and typically planar. Ni-rich silicide phases subsequently nucleate close to the Ni reservoir, which for as-grown SiNWs can lead to a complete channel break-off for prolonged silicidation due to significant volume expansion and morphological changes.

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