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1.
Phys Rev Lett ; 126(4): 042701, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33576674

RESUMO

Proton capture on the excited isomeric state of ^{26}Al strongly influences the abundance of ^{26}Mg ejected in explosive astronomical events and, as such, plays a critical role in determining the initial content of radiogenic ^{26}Al in presolar grains. This reaction also affects the temperature range for thermal equilibrium between the ground and isomeric levels. We present a novel technique, which exploits the isospin symmetry of the nuclear force, to address the long-standing challenge of determining proton-capture rates on excited nuclear levels. Such a technique has in-built tests that strongly support its veracity and, for the first time, we have experimentally constrained the strengths of resonances that dominate the astrophysical ^{26m}Al(p,γ)^{27}Si reaction. These constraints demonstrate that the rate is at least a factor ∼8 lower than previously expected, indicating an increase in the stellar production of ^{26}Mg and a possible need to reinvestigate sensitivity studies involving the thermal equilibration of ^{26}Al.

2.
Phys Rev Lett ; 125(23): 232501, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33337204

RESUMO

The neutron-rich nuclei in the N=28 island of inversion have attracted considerable experimental and theoretical attention, providing great insight into the evolution of shell structure and nuclear shape in exotic nuclei. In this work, for the first time, quadrupole collectivity is assessed simultaneously on top of the 3/2^{-} ground state and the 7/2^{-} shape-coexisting isomer of ^{43}S, putting the unique interpretation of shape and configuration coexistence at N=27 and 28 in the sulfur isotopic chain to the test. From an analysis of the electromagnetic transition strengths and quadrupole moments predicted within the shell model, it is shown that the onset of shape coexistence and the emergence of a simple collective structure appear suddenly in ^{43}S with no indication of such patterns in the N=27 isotone ^{45}Ar.

3.
Phys Rev Lett ; 124(15): 152501, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32357059

RESUMO

The lifetimes of the first excited 2^{+} states in the N=Z nuclei ^{80}Zr, ^{78}Y, and ^{76}Sr have been measured using the γ-ray line shape method following population via nucleon-knockout reactions from intermediate-energy rare-isotope beams. The extracted reduced electromagnetic transition strengths yield new information on where the collectivity is maximized and provide evidence for a significant, and as yet unexplained, odd-odd vs even-even staggering in the observed values. The experimental results are analyzed in the context of state-of-the-art nuclear density-functional model calculations.

4.
Phys Rev Lett ; 122(22): 222501, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31283300

RESUMO

A more detailed test of the implementation of nuclear forces that drive shell evolution in the pivotal nucleus ^{42}Si-going beyond earlier comparisons of excited-state energies-is important. The two leading shell-model effective interactions, SDPF-MU and SDPF-U-Si, both of which reproduce the low-lying ^{42}Si(2_{1}^{+}) energy, but whose predictions for other observables differ significantly, are interrogated by the population of states in neutron-rich ^{42}Si with a one-proton removal reaction from ^{43}P projectiles at 81 MeV/nucleon. The measured cross sections to the individual ^{42}Si final states are compared to calculations that combine eikonal reaction dynamics with these shell-model nuclear structure overlaps. The differences in the two shell-model descriptions are examined and linked to predicted low-lying excited 0^{+} states and shape coexistence. Based on the present data, which are in better agreement with the SDPF-MU calculations, the state observed at 2150(13) keV in ^{42}Si is proposed to be the (0_{2}^{+}) level.

5.
Phys Rev Lett ; 122(23): 232701, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31298878

RESUMO

The ^{23}Al(p,γ)^{24}Si reaction is among the most important reactions driving the energy generation in type-I x-ray bursts. However, the present reaction-rate uncertainty limits constraints on neutron star properties that can be achieved with burst model-observation comparisons. Here, we present a novel technique for constraining this important reaction by combining the GRETINA array with the neutron detector LENDA coupled to the S800 spectrograph at the National Superconducting Cyclotron Laboratory. The ^{23}Al(d,n) reaction was used to populate the astrophysically important states in ^{24}Si. This enables a measurement in complete kinematics for extracting all relevant inputs necessary to calculate the reaction rate. For the first time, a predicted close-lying doublet of a 2_{2}^{+} and (4_{1}^{+},0_{2}^{+}) state in ^{24}Si was disentangled, finally resolving conflicting results from two previous measurements. Moreover, it was possible to extract spectroscopic factors using GRETINA and LENDA simultaneously. This new technique may be used to constrain other important reaction rates for various astrophysical scenarios.

6.
Phys Rev Lett ; 121(8): 082502, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30192612

RESUMO

Neutron-deficient selenium isotopes are thought to undergo a rapid shape change from a prolate deformation near the line of beta stability towards oblate deformation around the line of N=Z. The point at which this shape change occurs is unknown, with inconsistent predictions from available theoretical models. A common feature in the models is the delicate nature of the point of transition, with the introduction of even a modest spin to the system sufficient to change the ordering of the prolate and oblate configurations. We present a measurement of the quadrupole moment of the first-excited state in radioactive ^{72}Se-a potential point of transition-by safe Coulomb excitation. This is the first low-energy Coulomb excitation to be performed with a rare-isotope beam at the reaccelerated beam facility at the National Superconducting Cyclotron Laboratory. By demonstrating a negative spectroscopic quadrupole moment for the first-excited 2^{+} state, it is found that any low-spin shape change in neutron-deficient selenium does not occur until ^{70}Se.

7.
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.

8.
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.

9.
Prog Urol ; 23(10): 869-76, 2013 Sep.
Artigo em Francês | MEDLINE | ID: mdl-24034799

RESUMO

INTRODUCTION: The aim of this study was to analyze the XPS laser learning curve of one single surgeon with no previous experience of PVP and the impact of the use of reel time transrectal ultrasound (TRUS) monitoring. MATERIALS AND METHODS: Retrospective analysis of the first 100 patients: group 1 (1st-49th patient without TRUS) and group 2 (50th-100th with TRUS). The learning curve was analyzed through technical variables: vaporization time/intervention time (VT/IT) (%), energy delivered (J)/prostate volume (J/mL) and delivered energy (J/s or Watt), peroperative conversion into monopolar transurethral resection, postoperative complication, duration of catheterization and hospitalization and evolution of International Prostate Symptom Score (IPSS), PSA level, prostate residual volume and Qmax. Relationships between variables were evaluated by analysing the covariance (R 2 software. 14.2). RESULTS: A significant increase in VT/IT (P=0.0001) and the energy delivered per mL prostate (P=0.043) was reported in group 1. The average energy delivered per second was significantly higher in group 2 (P=0.0016). No difference was observed in terms of intra- or postoperative complication and catheterization time. The duration of hospitalization was significantly shorter in group 2 (P=0.03). The use of TRUS was associated with a gain of energy delivered by prostate volume at the end of learning curve (P=0.018). Prostate residual volume was significantly lower in the group 2 (P=0.0004). CONCLUSION: In our experience, 50 procedures are required to achieve the learning curve of PVP. The use of reel time TRUS would increase the energy delivered by prostate volume.


Assuntos
Fotocoagulação a Laser/métodos , Próstata/diagnóstico por imagem , Hiperplasia Prostática/cirurgia , Ultrassonografia de Intervenção , Idoso , Humanos , Curva de Aprendizado , Tempo de Internação , Masculino , Duração da Cirurgia , Próstata/cirurgia , Hiperplasia Prostática/diagnóstico por imagem , Estudos Retrospectivos
10.
Prog Urol ; 22(5): 273-8, 2012 May.
Artigo em Francês | MEDLINE | ID: mdl-22515923

RESUMO

OBJECTIVE: To examine the association between statin use and prostate cancer (PC) stratified with D'Amico risk groups and biochemical recurrence (BR) in patients undergoing radical prostatectomy (RP). PATIENTS AND METHODS: All medical charts of patients managed from 2004 to 2008 for PC with RP were reviewed retrospectively. The use and the type of statin were identified. Patients were split according to the use (S+) or not (S-) of statin. The two groups were compared using the Chi(2) test. A logistic regression was performed for multivariate analysis. RESULTS: Overall, 377 patients were included. Mean age was 64 (48-76) (median, range). Ninety-seven patients (27.5%) used statin for at least a year. Groups S- and S+ were comparable in terms of age, obesity, diabetes, preoperative PSA, biopsy Gleason score or clinical stage. The use of statin was statistically associated with D'Amico risk groups (P=0.003). The number of high-risk PC was higher in Group S+ (23.7% vs. 10.7%) with an odds ratio of 2.4 (P=0.009). With a mean follow up of 33±10 months, the overall 2-years-BR was 89%. The 2-years-BR was higher in the S+ (93% vs. 88%, P=0.16). After adjustment, this difference was statistically significant with a hazard ratio of 0.46 (P=0.036). CONCLUSION: The use of statin was associated with high risk PC in this study. Surprisingly, the statin use seem also to be associated with better disease-free survival, independently of other risk factors.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Idoso , Intervalo Livre de Doença , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Medição de Risco
11.
JCI Insight ; 7(24)2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36346670

RESUMO

Clinical outcomes after lung transplantation, a life-saving therapy for patients with end-stage lung diseases, are limited by primary graft dysfunction (PGD). PGD is an early form of acute lung injury with no specific pharmacologic therapies. Here, we present a large multicenter study of plasma and bronchoalveolar lavage (BAL) samples collected on the first posttransplant day, a critical time for investigations of immune pathways related to PGD. We demonstrated that ligands for NKG2D receptors were increased in the BAL from participants who developed severe PGD and were associated with increased time to extubation, prolonged intensive care unit length of stay, and poor peak lung function. Neutrophil extracellular traps (NETs) were increased in PGD and correlated with BAL TNF-α and IFN-γ cytokines. Mechanistically, we found that airway epithelial cell NKG2D ligands were increased following hypoxic challenge. NK cell killing of hypoxic airway epithelial cells was abrogated with NKG2D receptor blockade, and TNF-α and IFN-γ provoked neutrophils to release NETs in culture. These data support an aberrant NK cell/neutrophil axis in human PGD pathogenesis. Early measurement of stress ligands and blockade of the NKG2D receptor hold promise for risk stratification and management of PGD.


Assuntos
Transplante de Pulmão , Disfunção Primária do Enxerto , Humanos , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Disfunção Primária do Enxerto/etiologia , Fator de Necrose Tumoral alfa , Transplante de Pulmão/efeitos adversos , Pulmão/metabolismo
12.
Radiother Oncol ; 61(2): 135-41, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11690678

RESUMO

PURPOSE: To evaluate reliability of Trans-rectal ultra-sonography (TRUS) guidance with lipiodol injection for prostate localization before radiotherapy planning. MATERIAL AND METHODS: From October 1997 to March 2000, 31 patients with prostatic adenocarcinoma and six patients with anastomotic recurrence after radical prostatectomy had TRUS-guided injection of lipiodol. Two milliliters of lipiodol were injected into each side of the prostate and 1 ml into both seminal vesicles with a 22 Gauge CHIBA needle and US probe guide before radiotherapy planning. We had established a contrast quality index (0 for no prostate enhancement to 5 for efficient pacification without any diffusion). On simulation films, we had performed anatomic measurements for comparison with other anatomic studies. RESULTS: For all 37 patients, TRUS-guided injection was well tolerated. Among 31 patients with the prostate in situ, three had no apex opacification and 15 had no vesicle enhancement or peri-vesicle space diffusion. However, in 19 patients there was good contrast quality with an index score of > or =3. The majority of patients had prostatic apex between 1.5 and 3.5 cm from ischial tuberosities ligne (27 from 28 evaluable for apex). Among 19 evaluable patients, 15 had seminal vesicles 2-4 cm above the top of pubis. For six patients with anastomotic recurrence after radical prostatectomy, lipiodol was precious aid to locate it. We had only one failure because of a precocious bladder absorption relating to a delay which is too long between rectal probe locating and portal films. CONCLUSION: TRUS injection of lipiodol is a simple, inexpensive, relatively safe technique for localization of prostatic apex, but not appropriate for seminal vesicles enhancement. This is also an interesting method to locate anastomotic recurrence.


Assuntos
Meios de Contraste/administração & dosagem , Óleo Iodado/administração & dosagem , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional , Humanos , Injeções , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Radioterapia Conformacional/métodos , Radioterapia de Alta Energia , Reprodutibilidade dos Testes , Ultrassonografia
13.
J Mal Vasc ; 14(2): 130-2, 1989.
Artigo em Francês | MEDLINE | ID: mdl-2754348

RESUMO

In a recent experience we have studied 297 patients for impotence. 102 were considered psychogenic and 195 organic; 105 of the latter had isolated or associated arterial or venous lesions. The remaining 81 patients had preponderant organic pathology: Peyronie's disease, neurological disease, diabetes and pelvic trauma. All patients were explored by NPT (nocturnal penile tumescence), Doppler examination, intra-cavernous papaverine test, angiography and erectile flow associated with cavernography. We report our microvascular surgery results from the last seven years. 80 reconstructive vascular procedures were performed on a population of patients who averaged 50 years of age. 50 epigastric-cavernous by-passes were performed. Complete recovery has been observed in 14% with an average of 42 months follow-up. Erection improvement with possibility of vaginal intromission in 58%. Immediate or secondary thrombosis and priapism in 28%. 21 arterial epigastric-dorsal unilateral by-passes were performed with an average follow-up of 20 months. In 11 cases the arterial micro-revascularization was associated with deep dorsal vein ligature. Results are as follows: 10 excellent, 4 significant improvement, 3 failures and too short follow-up in three. 9 isolated venous ligature with a mean follow-up of 15 months. Complete recovery was observed in 3 patients, improvement in 3 and failure in 2. The author emphasizes the interest of a better selection of surgical indications, improvement of microsurgical techniques with epigastric-dorsal anastomosis associated with postoperative anticoagulant therapy whenever possible.


Assuntos
Disfunção Erétil/etiologia , Doenças Vasculares/complicações , Disfunção Erétil/fisiopatologia , Disfunção Erétil/cirurgia , Seguimentos , Humanos , Masculino , Microcirurgia , Pessoa de Meia-Idade , Doenças Vasculares/cirurgia
14.
J Radiol ; 85(12 Pt 1): 1999-2004, 2004 Dec.
Artigo em Francês | MEDLINE | ID: mdl-15692410

RESUMO

PURPOSE: Determine the feasibility of dynamic gadolinium enhanced MRI and spectroscopic imaging in routine clinical practice using standard equipment and its usefulness for patients with negative biopsies and high degree of suspicion of prostate cancer. PATIENTS AND METHODS: Fifty five patients underwent endorectal MRI using T2W spin echo (SE) imaging, dynamic gadolinium enhanced imaging and proton spectroscopic imaging before repeat US-guided transrectal biopsies. The statistical analysis consisted in the correlation of the results obtained with each of the two MRI techniques and the results of the biopsies in the corresponding prostate lobe. RESULTS: 32 patients were included in the analysis. Biopsies revealed cancer for 15 patients. The statistical analysis showed a lack of significant correlation between T2W-SE imaging and biopsy results. A correlation with statistical significance was found between dynamic gadolinium enhanced imaging and biopsies (p=0,0018) and between spectroscopic imaging results and biopsies in the corresponding lobe (p=0,0001). CONCLUSION: Endorectal MRI with a standard clinical equipment using dynamic gadolinium enhanced imaging and spectroscopic imaging may be used in clinical routine to improve detection and localization in prostate cancer compared to T2 weighted spin echo imaging.


Assuntos
Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Neoplasias da Próstata/diagnóstico , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
15.
Ann Urol (Paris) ; 21(1): 23-6, 1987.
Artigo em Francês | MEDLINE | ID: mdl-3566202

RESUMO

Since 1981, 12 cases of stress incontinence in elderly, multi-operated women have been treated by one or several endoscopic injections of teflon. The definitive results, with a mean follow-up of 28 months, were as follows: 58% cures, 25% improvements and 16% failures. The urodynamic survey and cysto-urethrography revealed: unchanged urethral compliance, increased urethral tone and urethral length, improved abdomino-urethral transmission, increased bladder capacity, reduction in the posterior vesico-urethral angle and lifting of the bladder neck.


Assuntos
Politetrafluoretileno/administração & dosagem , Incontinência Urinária por Estresse/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Injeções , Pessoa de Meia-Idade , Uretra
16.
Ann Urol (Paris) ; 20(5): 353-4, 1986.
Artigo em Francês | MEDLINE | ID: mdl-2430502

RESUMO

The authors report the case of an exceptionally large prostatic adenoma (800 g) with a misleading clinical presentation: haematuria, signs of vascular compression, raised acid phosphatase, with no signs of urinary obstruction. Only repeated biopsies were able to confirm the benign nature of this hyperplasia, which justified surgical treatment.


Assuntos
Hiperplasia Prostática/patologia , Idoso , Diagnóstico Diferencial , Hematúria/etiologia , Humanos , Masculino , Osteíte Deformante/complicações , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/cirurgia , Micção
17.
Ann Urol (Paris) ; 22(5): 329-32, 1988.
Artigo em Francês | MEDLINE | ID: mdl-3202606

RESUMO

The case of a 38-year-old man with renal colic due to compression by an abdominopelvic mass is reported. Histologic examination of the mass led to the diagnosis of giant lymph node hyperplasia or Castleman disease. Surgical removal of the lesion ensured complete recovery with no recurrence after 32 months follow up. Giant lymph node hyperplasia usually develops in the mediastinum, but superficial and abdominopelvic forms are seen occasionally. Pathogenic hypotheses are discussed. Outcome is usually favorable following surgical excision but rare multifocal forms with a potentially poor prognosis have been reported.


Assuntos
Hiperplasia do Linfonodo Gigante/complicações , Cólica/etiologia , Nefropatias/etiologia , Adulto , Humanos , Masculino
18.
Cah Anesthesiol ; 33(7): 583-7, 1985 Nov.
Artigo em Francês | MEDLINE | ID: mdl-3912032

RESUMO

We studied for one year 60 patients separated in 3 groups of 20: first reference group without treatment; second group receiving netilmicin in premedication; third group treated by netilmicin for 2 days postoperatively. This series clearly demonstrates the high urinary tract infection rate after transurethral surgery, the benefit of antibioprophylaxis with netilmicin and the efficiency of one dose of this aminosid given one hour preoperatively.


Assuntos
Netilmicina/uso terapêutico , Infecções Urinárias/prevenção & controle , Sistema Urinário/cirurgia , Idoso , Ensaios Clínicos como Assunto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Prostatectomia , Uretra/cirurgia , Neoplasias da Bexiga Urinária/cirurgia
19.
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