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2.
Phys Rev Lett ; 125(17): 172501, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33156683

RESUMO

The ^{80}Ge structure was investigated in a high-statistics ß-decay experiment of ^{80}Ga using the GRIFFIN spectrometer at TRIUMF-ISAC through γ, ß-e, e-γ, and γ-γ spectroscopy. No evidence was found for the recently reported 0_{2}^{+} 639-keV level suggested as evidence for low-energy shape coexistence in ^{80}Ge. Large-scale shell model calculations performed in ^{78,80,82}Ge place the 0_{2}^{+} level in ^{80}Ge at 2 MeV. The new experimental evidence combined with shell model predictions indicate that low-energy shape coexistence is not present in ^{80}Ge.

3.
Phys Rev Lett ; 121(1): 012501, 2018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-30028163

RESUMO

Lifetime measurements of excited states in the neutron-rich nucleus ^{43}S were performed by applying the recoil-distance method on fast rare-isotope beams in conjunction with the Gamma-Ray Energy Tracking In-beam Nuclear Array. The new data based on γγ coincidences and lifetime measurements resolve a doublet of (3/2^{-}) and (5/2^{-}) states at low excitation energies. Results were compared to the π(sd)-ν(pf) shell model and antisymmetrized molecular dynamics calculations. The consistency with the theoretical calculations identifies a possible appearance of three coexisting bands near the ground state of ^{43}S: the K^{π}=1/2^{-} band built on a prolate-deformed ground state, a band built on an isomer with a 1f_{7/2}^{-1} character, and a suggested excited band built on a newly discovered doublet state. The latter further confirms the collapse of the N=28 shell closure in the neutron-rich region.

4.
Phys Rev Lett ; 121(26): 262501, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30636164

RESUMO

An enhanced low-energy electric dipole (E1) strength is identified for the weakly bound excited states of the neutron-rich isotope ^{27}Ne. The Doppler-shift lifetime measurements employing a combination of the γ-ray tracking array GRETINA, the plunger device, and the S800 spectrograph determine the lower limit of 0.030 e^{2} fm^{2} or 0.052 W.u. for the 1/2^{+}→3/2^{-} E1 transition in ^{27}Ne, representing one of the strongest E1 strengths observed among the bound discrete states in this mass region. This value is at least 30 times larger than that measured for the 3/2^{-} decay to the 3/2_{gs}^{+} ground state. A comparison of the present results to large-scale shell-model calculations points to an important role of core excitations and deformation in the observed E1 enhancement, suggesting a novel example of the electric dipole modes manifested in weakly bound deformed systems.

5.
Phys Rev Lett ; 118(5): 052501, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28211717

RESUMO

Previous experiments observed a 4^{+} state in the N=28 nucleus ^{44}S and suggested that this state may exhibit a hindered E2-decay rate, inconsistent with being a member of the collective ground state band. We populate this state via two-proton knockout from a beam of exotic ^{46}Ar projectiles and measure its lifetime using the recoil distance method with the GRETINA γ-ray spectrometer. The result, 76(14)_{stat}(20)_{syst} ps, implies a hindered transition of B(E2;4^{+}→2_{1}^{+})=0.61(19) single-particle or Weisskopf units strength and supports the interpretation of the 4^{+} state as a K=4 isomer, the first example of a high-K isomer in a nucleus of such low mass.

6.
Phys Rev Lett ; 116(12): 122502, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-27058074

RESUMO

The lifetimes of the first excited 2^{+} and 4^{+} states in ^{72}Ni were measured at the National Superconducting Cyclotron Laboratory with the recoil-distance Doppler-shift method, a model-independent probe to obtain the reduced transition probability. Excited states in ^{72}Ni were populated by the one-proton knockout reaction of an intermediate energy ^{73}Cu beam. γ-ray-recoil coincidences were detected with the γ-ray tracking array GRETINA and the S800 spectrograph. Our results provide evidence of enhanced transition probability B(E2;2^{+}→0^{+}) as compared to ^{68}Ni, but do not confirm the trend of large B(E2) values reported in the neighboring isotope ^{70}Ni obtained from Coulomb excitation measurement. The results are compared to shell model calculations. The lifetime obtained for the excited 4_{1}^{+} state is consistent with models showing decay of a seniority ν=4, 4^{+} state, which is consistent with the disappearance of the 8^{+} isomer in ^{72}Ni.

7.
Phys Rev Lett ; 112(14): 142502, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24765947

RESUMO

The transition rates from the yrast 2+ and 4+ states in the self-conjugate 72Kr nucleus were studied via lifetime measurements employing the GRETINA array with a novel application of the recoil-distance method. The large collectivity observed for the 4+→2+ transition suggests a prolate character of the excited states. The reduced collectivity previously reported for the 2+→0+ transition was confirmed. The irregular behavior of collectivity points to the occurrence of a rapid oblate-prolate shape transition in 72Kr, providing stringent tests for advanced theories to describe the shape coexistence and its evolution.

8.
Int Urogynecol J ; 21(12): 1553-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20972541

RESUMO

This study aims to review the use of sacral neuromodulation in the patient population with painful bladder syndrome/interstitial cystitis (PBS/IC), chronic pelvic pain (CPP), and sexual dysfunction. A literature review of the current research was carried out. This article highlights the current research findings and uses of sacral neuromodulation in patients with PBS/IC, CPP, vulvar vestibulitis, and erectile dysfunction. Current research on sacral neuromodulation on the abovementioned patient population has shown potential efficacy in pilot studies, though larger, multi-centered trials with long-term follow-up are needed.


Assuntos
Terapia por Estimulação Elétrica , Sacro/inervação , Raízes Nervosas Espinhais/fisiologia , Doença Crônica , Cistite Intersticial/terapia , Feminino , Humanos , Dor Pélvica/terapia , Disfunções Sexuais Fisiológicas/terapia , Resultado do Tratamento
9.
Urology ; 49(5A Suppl): 58-63, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9146003

RESUMO

OBJECTIVES: To develop 2 brief self-administered indices for measuring lower urinary tract symptoms and their impact in patients with interstitial cystitis (IC). METHODS: An initial set of questions was developed and evaluated in focus groups. The index was revised, shortened, and validated with patients diagnosed in 3 large urologic practices with experience in interstitial cystitis (N = 45). Controls were recruited from a group of healthy volunteers in a gynecology clinic (N = 67). Internal consistency, construct validity, and test-retest reliability were evaluated. RESULTS: The IC symptom index and the IC problem index measure urinary and pain symptoms and assesses how problematic symptoms are for patients with interstitial cystitis. Psychometric performance of both instruments is good, with the symptom index demonstrating excellent ability to discriminate characteristics between patients and controls. CONCLUSION: Both indices should be useful in the evaluation and management of patients with IC and should be particularly useful in clinical trials of new therapies for this condition, where reliable, validated, and reproducible outcome measures are critically important.


Assuntos
Cistite Intersticial/diagnóstico , Inquéritos e Questionários , Humanos , Índice de Gravidade de Doença
10.
Urology ; 42(6): 646-52, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8256398

RESUMO

One theory for the etiology of interstitial cystitis (IC) proposes toxic substances in the urine. This hypothesis was tested in our laboratory by infusing urine into the bladders of rabbits twice weekly for six weeks. For the first study rabbits were treated by one-hour biweekly intravesical exposure to urine from a symptomatic interstitial cystitis patient, a normal volunteer, or physiologic saline. For the second study, animals were exposed to both a high and a low molecular weight fraction of urine pooled from 7 interstitial cystitis patients, 7 normal female volunteers, and physiologic saline. At the end of six weeks the animals were cystoscoped and the bladder was removed the following day for histologic and contractile studies. Post-distention glomerulations were observed in 3 of the 4 whole IC urine-treated animals and an ulcer identical to the classic "Hunner's ulcer" was seen in one of these animals. Post-distention petechial hemorrhages were also noted in all 5 of the high molecular weight IC urine-treated animals but in none of the others, suggesting a difference between IC and normal urine. These IC urine-treated groups also showed the greatest degree of histologic changes including edema and plasma cell infiltrates in the lamina propria, submucosa and perivascular tissue. However, there was no statistically significant difference in bladder capacity, micturition patterns, or contractile response of bladder strips. These results indicate that there are substances with nominal molecular weight greater than 10 kD in interstitial cystitis urine that induce changes in the rabbit bladder that resemble bladders of interstitial cystitis patients.


Assuntos
Cistite , Bexiga Urinária/patologia , Urina/fisiologia , Administração Intravesical , Animais , Reações Antígeno-Anticorpo , Cistite/imunologia , Humanos , Peso Molecular , Músculo Liso/patologia , Músculo Liso/fisiologia , Coelhos , Bexiga Urinária/imunologia , Bexiga Urinária/fisiologia , Urina/química
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