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2.
Nat Commun ; 12(1): 4805, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376669

RESUMO

Proton radioactivity was discovered exactly 50 years ago. First, this nuclear decay mode sets the limit of existence on the nuclear landscape on the neutron-deficient side. Second, it comprises fundamental aspects of both quantum tunnelling as well as the coupling of (quasi)bound quantum states with the continuum in mesoscopic systems such as the atomic nucleus. Theoretical approaches can start either from bound-state nuclear shell-model theory or from resonance scattering. Thus, proton-radioactivity guides merging these types of theoretical approaches, which is of broader relevance for any few-body quantum system. Here, we report experimental measurements of proton-emission branches from an isomeric state in 54mNi, which were visualized in four dimensions in a newly developed detector. We show that these decays, which carry an unusually high angular momentum, ℓ = 5 and ℓ = 7, respectively, can be approximated theoretically with a potential model for the proton barrier penetration and a shell-model calculation for the overlap of the initial and final wave functions.

3.
Phys Rev Lett ; 126(7): 072501, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666458

RESUMO

We studied the proton-rich T_{z}=-1 nucleus ^{70}Kr through inelastic scattering at intermediate energies in order to extract the reduced transition probability, B(E2;0^{+}→2^{+}). Comparison with the other members of the A=70 isospin triplet, ^{70}Br and ^{70}Se, studied in the same experiment, shows a 3σ deviation from the expected linearity of the electromagnetic matrix elements as a function of T_{z}. At present, no established nuclear structure theory can describe this observed deviation quantitatively. This is the first violation of isospin symmetry at this level observed in the transition matrix elements. A heuristic approach may explain the anomaly by a shape change between the mirror nuclei ^{70}Kr and ^{70}Se contrary to the model predictions.

4.
Phys Rev Lett ; 122(22): 222502, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31283269

RESUMO

A record number of ^{100}Sn nuclei was detected and new isotopic species toward the proton dripline were discovered at the RIKEN Nishina Center. Decay spectroscopy was performed with the high-efficiency detector arrays WAS3ABi and EURICA. Both the half-life and the ß-decay end point energy of ^{100}Sn were measured more precisely than the literature values. The value and the uncertainty of the resulting strength for the pure 0^{+}→1^{+} Gamow-Teller decay was improved to B_{GT}=4.4_{-0.7}^{+0.9}. A discrimination between different model calculations was possible for the first time, and the level scheme of ^{100}In is investigated further.

5.
Unfallchirurg ; 120(2): 167-170, 2017 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-27757484

RESUMO

One representative case of burns caused by the negligent use of bioethanol, which was treated at our burns centre is used to illustrate the severity and depth of the burn injuries as well as the complexity of the further long-term course of treatment including complex secondary-reconstructive techniques.


Assuntos
Queimaduras/etiologia , Queimaduras/cirurgia , Etanol , Procedimentos de Cirurgia Plástica/métodos , Pele/lesões , Retalhos Cirúrgicos , Acidentes Domésticos , Adulto , Queimaduras/diagnóstico , Terapia Combinada/métodos , Procedimentos Cirúrgicos Dermatológicos/métodos , Feminino , Humanos , Imperícia , Prevenção Secundária/métodos , Pele Artificial , Resultado do Tratamento
6.
Phys Rev Lett ; 117(16): 162501, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27792367

RESUMO

In an experiment with the BigRIPS separator at the RIKEN Nishina Center, we observed two-proton (2p) emission from ^{67}Kr. At the same time, no evidence for 2p emission of ^{59}Ge and ^{63}Se, two other potential candidates for this exotic radioactivity, could be observed. This observation is in line with Q value predictions which pointed to ^{67}Kr as being the best new candidate among the three for two-proton radioactivity. ^{67}Kr is only the fourth 2p ground-state emitter to be observed with a half-life of the order of a few milliseconds. The decay energy was determined to be 1690(17) keV, the 2p emission branching ratio is 37(14)%, and the half-life of ^{67}Kr is 7.4(30) ms.

7.
Phys Rev Lett ; 116(16): 162501, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27152796

RESUMO

Several new isotopes, ^{96}In, ^{94}Cd, ^{92}Ag, and ^{90}Pd, have been identified at the RIKEN Nishina Center. The study of proton drip-line nuclei in the vicinity of ^{100}Sn led to the discovery of new proton emitters ^{93}Ag and ^{89}Rh with half-lives in the submicrosecond range. The systematics of the half-lives of odd-Z nuclei with T_{z}=-1/2 toward ^{99}Sn shows a stabilizing effect of the Z=50 shell closure. Production cross sections for nuclei in the vicinity of ^{100}Sn measured at different energies and target thicknesses were compared to the cross sections calculated by epax taking into account contributions of secondary reactions in the primary target.

8.
Clin Hemorheol Microcirc ; 64(3): 333-344, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28128750

RESUMO

BACKGROUND: The reconstruction of metacarpal- and interphalangeal joints after severe hand injuries has been proven to be challenging. Commonly used procedures like arthrodesis, amputation or ray resection of the finger compromise the functionality of the injured finger. Especially for young patients, the restoration of all functions of the fingers is a priority. Local tissue transfers for finger joint reconstructions is not an option due to inacceptable donor site morbidity; microsurgical tissue transfers in terms of free toe joint transfers have proven to be a valuable method. METHODS: We present the case of a patient who suffered an excessive injury from a circular saw to his dominant hand. The MCP Joints of D2-D4 were fully destroyed, along with the PIP joint of a subtotally amputated D4. Arteries, nerves and tendons could be coapted directly, while primarily reconstructing of the finger joints was impossible. To ensure a possible regain of full functionality, two coherent joints, the MTP and the PIP of one toe, were transferred to the ring finger as a single transplant, reconstructing the MCP and the PIP joints of the injured finger in a one step procedure. Additionally the MCP joint of the D2 was reconstructed by the use of a free PIP-joint transfer, further the MCP joint of the D3 was replaced by an MCP endoprosthesis. RESULTS: After a follow up of 3 years the patient displayed full function of his dominant hand including sensitivity, and has gone back to manual work without limitations. The result was cosmetically acceptable and the donor site defect was easily being tolerated by the patient who is playing soccer in the regional soccer league. CONCLUSION: Free double toe joint transfer has been proven feasible in this patient. While transferring a single toe joint to reconstruct a finger joint is a well-established method, our review of the latest literature showed no case of a free transfer of two coherent joints and three transplanted joints in one hand. The applied microsurgical technique should be considered by microsurgically trained hand surgeons for the treatment of comparable severe hand injuries. In comparison to the most common procedures described for the repair and reconstruction of severely injured finger joints this method showed superior results.


Assuntos
Dedos/transplante , Articulação Metacarpofalângica/cirurgia , Articulação do Dedo do Pé/cirurgia , Adolescente , Humanos , Masculino , Articulação do Dedo do Pé/patologia
9.
Phys Rev Lett ; 112(22): 222501, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24949762

RESUMO

We report the observation of a very exotic decay mode at the proton drip line, the ß-delayed γ-proton decay, clearly seen in the ß decay of the T_{z}=-2 nucleus ^{56}Zn. Three γ-proton sequences have been observed after the ß decay. Here this decay mode, already observed in the sd shell, is seen for the first time in the fp shell. Both γ and proton decays have been taken into account in the estimation of the Fermi and Gamow-Teller strengths. Evidence for fragmentation of the Fermi strength due to strong isospin mixing is found.

10.
Phys Rev Lett ; 107(10): 102502, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21981498

RESUMO

The two protons emitted in the decay of 54Zn have been individually observed for the first time in a time projection chamber. The total decay energy and the half-life measured in this work agree with the results obtained in a previous experiment. Angular and energy correlations between the two protons are determined and compared to theoretical distributions of a three-body model. Within the shell model framework, the relative decay probabilities show a strong contribution of the p2 configuration for the two-proton emission. After 45Fe, the present result on 54Zn constitutes only the second case of a direct observation of the ground state two-proton decay of a long-lived isotope.

11.
Int J Otolaryngol ; 2009: 361427, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20130762

RESUMO

Primary hyperparathyroidism may cause fetal demise in pregnant patients if prompt diagnosis and treatment is not initiated. The paper describes a novel guide wire technique for a targeted parathyroidectomy, which may reduce the risk to mother and fetus and be useful in other related circumstances.

12.
Phys Rev Lett ; 99(10): 102501, 2007 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-17930383

RESUMO

The decay of the ground-state two-proton emitter 45Fe was studied with a time-projection chamber and the emission of two protons was unambiguously identified. The total decay energy and the half-life measured in this work agree with the results from previous experiments. The present result constitutes the first direct observation of the individual protons in the two-proton decay of a long-lived ground-state emitter. In parallel, we identified for the first time directly two-proton emission from 43Cr, a known beta-delayed two-proton emitter. The technique developed in the present work opens the way to a detailed study of the mechanism of ground state as well as beta-delayed two-proton radioactivity.

13.
Phys Rev Lett ; 99(8): 082502, 2007 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-17930944

RESUMO

Gamma rays deexciting states in the proton emitter 145Tm were observed using the recoil-decay tagging method. The 145Tm ground-state rotational band was found to exhibit the properties expected for an h{11/2} proton decoupled band. In addition, coincidences between protons feeding the 2{+} state in 144Er and the 2{+}-->0{+} gamma-ray transition were detected, the first measurement of this kind, leading to a more precise value for the 2{+} excitation energy of 329(1) keV. Calculations with the particle-rotor model and the core quasiparticle coupling model indicate that the properties of the pi{11/2} band and the proton-decay rates in 145Tm are consistent with the presence of triaxiality with an asymmetry parameter gamma approximately 20 degrees .


Assuntos
Raios gama , Prótons
14.
Zentralbl Chir ; 132(3): 220-5; discussion 225-6, 2007 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-17610193

RESUMO

INTRODUCTION: The indications for endovascular aortic aneurysm repair (EVAR) are mainly established in hostile abdomen, in patients with significant comorbidities which affect the general operability of the patient and, given the necessary infrastructure, also in ruptured aneurysm. Along to those, we present another possible indication in the presence of a kidney allograft in patients with aortic aneurysm. METHODS: Based on a case report of aorto-biiliac stent-graft repair of an infrarenal aortic aneurysm in a patient with renal allograft, a systematic review of the literature was performed of all similar cases concerning surgical therapy in this constellation. RESULTS: EVAR was performed using an aorto-biiliac system (Zenith) Trifab, COOK) in a 61-year-old male patient 11 years after heterotopic renal allotransplantation in the right iliac fossa. Preoperative renal function was normal. Because the donor renal artery was anastomosed to the recipient's external iliac artery the stent-graft was implanted from the left common femoral artery to minimize temporary allograft ischemia. The intra- and postoperative course was uneventful with a follow-up of presently 12 months. A primary type-II endoleak (retroleak from a lumbar artery) is being treated conservatively so far with embolization being a future option. At present there are 15 cases of EVAR in renal allograft patients that have been reported, all of them being successful. DISCUSSION: All data existing in the literature reported to date as well as our own experience justify the first choice of EVAR in morphologically suitable cases. One major advantage of EVAR in this constellation is the avoidance of aortic cross clamping which poses the graft at risk of ischemia. Long-term results will be most important for definite assessment of EVAR. However, contrast media application during the operation and for CT surveillance should be considered as a major disadvantage.


Assuntos
Angioplastia , Aneurisma da Aorta Abdominal/cirurgia , Prótese Vascular , Aneurisma Ilíaco/cirurgia , Transplante de Rim , Complicações Pós-Operatórias/cirurgia , Stents , Transplante Heterotópico , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aortografia , Comorbidade , Embolização Terapêutica , Seguimentos , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/cirurgia , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Artéria Renal/diagnóstico por imagem , Artéria Renal/cirurgia , Fatores de Risco , Tomografia Computadorizada por Raios X
15.
Phys Rev Lett ; 98(16): 162501, 2007 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-17501414

RESUMO

Ramsey's method of separated oscillatory fields is applied to the excitation of the cyclotron motion of short-lived ions in a Penning trap to improve the precision of their measured mass values. The theoretical description of the extracted ion-cyclotron-resonance line shape is derived and its correctness demonstrated experimentally by measuring the mass of the short-lived 38Ca nuclide with an uncertainty of 1.1 x 10(-8) using the Penning trap mass spectrometer ISOLTRAP at CERN. The mass of the superallowed beta emitter 38Ca contributes for testing the theoretical corrections of the conserved-vector-current hypothesis of the electroweak interaction. It is shown that the Ramsey method applied to Penning trap mass measurements yields a statistical uncertainty similar to that obtained by the conventional technique but 10 times faster. Thus the technique is a new powerful tool for high-precision mass measurements.

16.
Phys Rev Lett ; 94(23): 232501, 2005 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-16090464

RESUMO

The nucleus 54Zn has been observed for the first time in an experiment at the SISSI/LISE3 facility of GANIL in the quasifragmentation of a 58Ni beam at 74.5 MeV/nucleon in a (nat)Ni target. The fragments were analyzed by means of the ALPHA-LISE3 separator and implanted in a silicon-strip detector where correlations in space and time between implantation and subsequent decay events allowed us to generate almost background free decay spectra for about 25 different nuclei at the same time. Eight 54Zn implantation events were observed. From the correlated decay events, the half-life of 54Zn is determined to be 3.2(+1.8)(-0.8) ms. Seven of the eight implantations are followed by two-proton emission with a decay energy of 1.48(2) MeV. The decay energy and the partial half-life are compared to model predictions and allow for a test of these two-proton decay models.

17.
Phys Rev Lett ; 92(19): 192501, 2004 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-15169397

RESUMO

Mass measurements of 68Ge, 68As, and 68Se have been obtained with the Canadian Penning Trap mass spectrometer. The results determine the mass excess of 68Se as -54 232(19) keV, the first measurement with a precision and reliability sufficient to address the light-curve and energy output of x-ray bursts as well as the abundances of the elements synthesized. Under typical conditions used for modeling x-ray bursts, 68Se is found to cause a significant delay in the rp process nucleosynthesis.

18.
Phys Rev Lett ; 90(8): 082502, 2003 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-12633421

RESUMO

A new isomeric 0(+) state was identified as the first excited state in the self-conjugate (N=Z) nucleus 72Kr. By combining for the first time conversion-electron and gamma-ray spectroscopy with the production of metastable states in high-energy fragmentation, the electric-monopole decay of the new isomer to the ground state was established. The new 0(+) state is understood as the band head of the known prolate rotational structure, which strongly supports the interpretation that 72Kr is one of the rare nuclei having an oblate-deformed ground state. This observation gives in fact the first evidence for a shape isomer in a N=Z nucleus.

19.
Phys Rev Lett ; 89(10): 102501, 2002 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-12225187

RESUMO

In an experiment at the SISSI-LISE3 facility of GANIL, the decay of the proton drip line nucleus 45Fe has been studied. Fragment-implantation events have been correlated with radioactive decay events in a 16x16 pixel silicon-strip detector. The decay-energy spectrum of 45Fe implants shows a distinct peak at (1.14+/-0.04) MeV with a half-life of T(1/2)=(4.7(+3.4)(-1.4)) ms. None of the events in this peak is in coincidence with beta particles. For a longer correlation interval, daughter decays of the two-proton daughter 43Cr can be observed after 45Fe implantation. The decay energy for 45Fe agrees nicely with several theoretical predictions for two-proton radioactivity.

20.
J Clin Virol ; 25(1): 29-38, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12126719

RESUMO

OBJECTIVE: To evaluate the value of late-pp67-mRNA nucleic acid sequence-based amplification (NASBA) in comparison to DNA-PCR, blood culture and pp65-antigenemia assay for the detection of human cytomegalovirus (HCMV) disease in HIV-infected patients. METHODS: The results of pp67-mRNA NASBA, DNA-PCR, culture and pp65-antigenemia assay were compared in 402 whole blood specimens of 98 HIV-infected patients with a low CD4 lymphocyte count who had not yet received highly active antiretroviral therapy (HAART). Thirty-seven samples were obtained from 30 patients with a diagnosis of HCMV disease and 365 samples from 68 patients without HCMV disease. RESULTS: The highest agreement of test results was observed between pp67-mRNA NASBA and quantitative pp65-antigenemia, with a threshold of nine antigen-positive cells/10(5) leukocytes (kappa-value 0.70, 95% CI=0.58-0.82). The sensitivity of pp67-mRNA NASBA for the diagnosis of HCMV disease (59.3%) was identical to that of the quantitative pp65-antigenemia assay, higher than that of the blood culture (48.2%) but lower than that of the DNA-PCR (77.8%). Pp67-mRNA NASBA (92.3%), quantitative pp65-antigenemia assay (92.3%) and blood culture (93.9%) were highly specific for the diagnosis of HCMV disease and as a result, had a higher positive predictive value (76.2, 76.2 and 76.5%, respectively) than the qualitative DNA-PCR (58.3%) and the qualitative pp65-antigenemia assay (47.6%). CONCLUSION: pp67-mRNA NASBA, an easy and rapid to perform assay, well-standardised by virtue of co-amplified internal system control RNA, provides a high specificity and positive predictive value for the diagnosis of HCMV disease in HIV-infected patients, comparable to that of the quantitative pp65-antigenemia assay and blood culture.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/virologia , Antígenos Virais/genética , Infecções por Citomegalovirus/virologia , Fosfoproteínas/genética , RNA Mensageiro/sangue , RNA Viral/sangue , Proteínas da Matriz Viral/genética , Infecções Oportunistas Relacionadas com a AIDS/sangue , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Adulto , Antígenos Virais/sangue , Terapia Antirretroviral de Alta Atividade , Citomegalovirus/genética , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/diagnóstico , Feminino , Seguimentos , Amplificação de Genes/genética , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Fosfoproteínas/sangue , Estudos Prospectivos , Sensibilidade e Especificidade , Proteínas da Matriz Viral/sangue
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