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INTRODUCTION: This study examines the efficacy of prophylactic mesh implantation during open radical cystectomy with ileal conduit diversion in preventing parastomal hernias (PH). Despite PH being a common complication, prophylactic methods have been underexplored. METHODS: A pilot, single-center, prospective cohort study was conducted involving five patients undergoing surgery with mesh implantation. Demographic and clinical characteristics were monitored, including the incidence of PH, operation time, blood loss, and hospitalization duration. RESULTS: During the mean follow-up period of 9.1±3.2 months post-operation, no occurrences of PH were observed in the patient group. Despite the risks associated with implanting foreign material in an area of surgery involving open small intestine, no infectious complications were noted. CONCLUSION: Prophylactic mesh implantation in radical cystectomy with ileal conduit diversion appears to be an effective preventive measure against PH. Further extensive studies are required to definitively confirm the efficacy and safety of mesh use in this context.
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Cistectomia , Telas Cirúrgicas , Derivação Urinária , Humanos , Cistectomia/efeitos adversos , Cistectomia/métodos , Derivação Urinária/efeitos adversos , Projetos Piloto , Masculino , Idoso , Estudos Prospectivos , Hérnia Incisional/prevenção & controle , Hérnia Incisional/etiologia , Feminino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Neoplasias da Bexiga Urinária/cirurgiaRESUMO
The magnetic dipole transition strength B(M1) of ^{48}Ca is dominated by a single resonant state at an excitation energy of 10.23 MeV. Experiments disagree about B(M1) and this impacts our understanding of spin flips in nuclei. We performed ab initio computations based on chiral effective field theory and found that B(M1: 0^{+}â1^{+}) lies in the range from 7.0 to 10.2 µ_{N}^{2}. This is consistent with a (γ,n) experiment but larger than results from (e,e^{'}) and (p,p^{'}) scattering. Two-body currents yield no quenching of the B(M1) strength and continuum effects reduce it by about 10%. For a validation of our approach, we computed magnetic moments in ^{47,49}Ca and performed benchmark calculations in light nuclei.
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INTRODUCTION: Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disease that leads to chronic renal failure in about half of patients. It is a multisystemic disease with a predominance of kidney involvement, which significantly worsens the patient's health. Controversial issues include the indication and the timing and technique of nephrectomy of native polycystic kidneys. METHODS: A retrospective observational study focused on the surgical aspects of patients with ADPKD who underwent native nephrectomy at our institution. The group included patients operated on in the period 1/1/2000-31/12/2020. A total of 115 patients with ADPKD were enrolled (14.7% of all transplant recipients). We evaluated the basic demographic data, type of surgery, indications and complications in this group. RESULTS: Native nephrectomy was performed in 68 out of a total of 115 (59%) patients. Unilateral nephrectomy was done in 22 (32%) patients and bilateral in 46 (68%). The most common indications were infections (42 patients, 36%), pain (31 patients, 27%), hematuria (14 patients, 12%), gastrointestinal reasons (1 patient, 1%), respiratory reasons (1 patient, 1%), obtaining a site for transplantation (17 patients, 15%) and suspected tumor (5 patients, 4%). CONCLUSION: Native nephrectomy is recommended in symptomatic kidneys, or in asymptomatic kidneys when it is necessary to obtain a place for kidney transplantation, and in kidneys where a tumor is suspected.
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Transplante de Rim , Rim Policístico Autossômico Dominante , Humanos , Transplante de Rim/métodos , Rim Policístico Autossômico Dominante/complicações , Rim Policístico Autossômico Dominante/patologia , Rim Policístico Autossômico Dominante/cirurgia , Estudos Retrospectivos , Rim/patologia , Nefrectomia/métodosRESUMO
The rate at which helium (^{4}He) and deuterium (d) fuse together to produce lithium-6 (^{6}Li) and a γ ray, ^{4}He(d,γ)^{6}Li, is a critical puzzle piece in resolving the discrepancy between big bang predictions and astronomical observations for the primordial abundance of ^{6}Li. The accurate determination of this radiative capture rate requires the quantitative and predictive description of the fusion probability across the big bang energy window (30 keVâ²Eâ²400 keV), where measurements are hindered by low counting rates. We present first-principle (or, ab initio) predictions of the ^{4}He(d,γ)^{6}Li astrophysical S factor using validated nucleon-nucleon and three-nucleon interactions derived within the framework of chiral effective field theory. By employing the ab initio no-core shell model with continuum to describe ^{4}He-d scattering dynamics and bound ^{6}Li product on an equal footing, we accurately and consistently determine the contributions of the main electromagnetic transitions driving the radiative capture process. Our results reveal an enhancement of the capture probability below 100 keV owing to previously neglected magnetic dipole (M1) transitions and reduce by an average factor of 7 the uncertainty of the thermonuclear capture rate between 0.002 and 2 GK.
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Collinear laser spectroscopy is performed on the nickel isotopes ^{58-68,70}Ni, using a time-resolved photon counting system. From the measured isotope shifts, nuclear charge radii R_{c} are extracted and compared to theoretical results. Three ab initio approaches all employ, among others, the chiral interaction NNLO_{sat}, which allows an assessment of their accuracy. We find agreement with experiment in differential radii δ⟨r_{c}^{2}⟩ for all employed ab initio methods and interactions, while the absolute radii are consistent with data only for NNLO_{sat}. Within nuclear density functional theory, the Skyrme functional SV-min matches experiment more closely than the Fayans functional Fy(Δr,HFB).
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We use coupled-cluster theory and nuclear interactions from chiral effective field theory to compute the nuclear matrix element for the neutrinoless double-ß decay of ^{48}Ca. Benchmarks with the no-core shell model in several light nuclei inform us about the accuracy of our approach. For ^{48}Ca we find a relatively small matrix element. We also compute the nuclear matrix element for the two-neutrino double-ß decay of ^{48}Ca with a quenching factor deduced from two-body currents in recent ab initio calculation of the Ikeda sum rule in ^{48}Ca [Gysbers et al., Nat. Phys. 15, 428 (2019)NPAHAX1745-247310.1038/s41567-019-0450-7].
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A recently modified method to enable low-energy nuclear scattering results to be extracted from the discrete energy levels of the target-projectile clusters confined by harmonic potential traps is tested. We report encouraging results for neutron-α and neutron-^{24}O elastic scattering from analyzing the trapped levels computed using two different ab initio nuclear structure methods. The n-α results have also been checked against a direct ab initio reaction calculation. The n-^{24}O results demonstrate the approach's applicability for a large range of systems provided their spectra in traps can be computed by ab initio methods. A key ingredient is a rigorous understanding of the errors in the calculated energy levels caused by inevitable Hilbert-space truncations in the ab initio methods.
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We compare for the first time the influence of different Yb:YAG gain media on the performance of a large-area, high average-power laser system with an output energy of up to 6 J. Monocrystalline slabs grown by a new technique without central growth defect are compared with ceramics. Small signal gain, maximum output energy and thermal lensing are compared for ceramic slabs with co-sintered amplified spontaneous emission (ASE) absorber cladding, monocrystalline slab with and without optically bonded ASE absorber cladding, and surface structured monocrystalline slabs. We show that these large monocrystals with optically bonded absorber cladding have similar performance to cladded ceramics, so far the only material for high-energy Yb:YAG lasers.
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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 â¼200 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.
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We derive ab initio optical potentials from self-consistent Green's function theory and compute the elastic scattering of neutrons off oxygen and calcium isotopes. The comparison with scattering data is satisfactory at low scattering energies. The method is benchmarked against the no-core shell model with continuum calculations, showing that virtual excitations of the target are crucial to predict proper fragmentation and absorption at higher energies. This is a significant step toward deriving optical potentials for medium mass nuclei and complex many-body systems in general.
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INTRODUCTION: Symptomatic lymphocele could impair the function of a graft kidney. The aim of our research was to conduct a five-year follow-up after symptomatic lymphocele therapy. METHODS: Overall 50 patients undergoing the therapy of symptomatic lymphocele were enrolled in the study cohort. Demographic data, renal failure causes, indication of therapy and lymphocele management were retrospectively evaluated. Laboratory tests were done to evaluate serum creatinine, total plasma protein and albumin levels. Survival rates of the patients and of the grafts were analysed using Kaplan-Meier curves. RESULTS: The mean age of the 50 patients (44% females, 56% males) was 51.5±11.8 years, and the time between kidney transplantation and symptomatic lymphocele diagnosis was 12.8±21.5 months. Average lymphocele diameter was 71±35 mm. Causes of the native kidney failure were: glomerulonephritis (34%), tubulointerstitial nephritis (30%), polycystosis (24%), diabetic nephropathy (10%) and nephrosclerosis (2%). The therapy indications were: serum creatinine elevation (44%), graft hydronephrosis (38%), serum creatinine elevation associated with hydronephrosis (8%), infection associated with hydronephrosis (6%) and infection (4%). The lymphocele was managed by: open surgical intraperitoneal drainage (40%), percutaneous aspiration (26%), percutaneous long-term drainage (18%) and laparoscopic intraperitoneal drainage (16%). Mean serum creatinine levels at the time of the therapy and 60 months later were 231 µmol/L and 172 µmol/L, respectively; total plasma protein levels were 59 g/L and 69 g/L, respectively; albumin plasma levels were 36 g/L and 43 g/L, respectively. The five-year patient survival rate was 86% and the graft survival rate was 66%. CONCLUSION: Adequate management of symptomatic lymphocele stabilizes the graft function. If the post-transplant lymphocele is indicated for therapy, the therapy should be applied as soon as possible to prevent fibrous changes in the surrounding tissues. No patient death or graft loss had any direct relationship with lymphocele management.
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Transplante de Rim , Linfocele , Adulto , Drenagem , Feminino , Seguimentos , Humanos , Linfocele/etiologia , Linfocele/terapia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The aim of the study was to evaluate the role of colloid osmotic pressure in post-transplant lymphocele pathogenesis. We have analyzed total plasmatic protein and albumin levels, and electrophoresis has been completed in blood samples before transplantation and in days 3 and 14 after transplantation in 50 patients with lymphocele (Lymphocele) and 198 patients without lymphocele (control), respectively. Colloid osmotic pressure (COP) was calculated according to the Hoefs formula. Statistically significant differences were confirmed in albumin levels (42.2 respectively 44.8 g/L) before transplantation (day 0); in total protein (52.5 resp. 55.5 g/L), in albumin (30.1 resp. 32.1 g/L), and COP (15.6 respectively 17.7 kPa) in day 3; and in total protein (52.8 resp. 58.9 g/L), in albumin (30.5 respectively 35.4 g/L), in COP (16.1 respectively 21.2 kPa) in day 14. A potentially critical albumin level was established in 44.1 g/L in the blood analyzed, but its sensitivity was only 62%. The main risk element for the lymphocele formation remains the surgeon's hand. We can proclaim the role of proteins and their COP in the post-transplant lymphocele formation as one of possible pathogenetic cofactors. It is responsible for the impaired mechanisms of the reabsorption the lymph back to the tissues. Better metabolic care could help to reduce incidence of this surgical complication.
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Transplante de Rim/efeitos adversos , Linfocele/sangue , Linfocele/etiologia , Complicações Pós-Operatórias/etiologia , Adulto , Proteínas Sanguíneas/metabolismo , Coloides/metabolismo , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pressão Osmótica , Complicações Pós-Operatórias/epidemiologia , Albumina Sérica/metabolismoRESUMO
A precision mass investigation of the neutron-rich titanium isotopes ^{51-55}Ti was performed at TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). The range of the measurements covers the N=32 shell closure, and the overall uncertainties of the ^{52-55}Ti mass values were significantly reduced. Our results conclusively establish the existence of the weak shell effect at N=32, narrowing down the abrupt onset of this shell closure. Our data were compared with state-of-the-art ab initio shell model calculations which, despite very successfully describing where the N=32 shell gap is strong, overpredict its strength and extent in titanium and heavier isotones. These measurements also represent the first scientific results of TITAN using the newly commissioned multiple-reflection time-of-flight mass spectrometer, substantiated by independent measurements from TITAN's Penning trap mass spectrometer.
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How does nature hold together protons and neutrons to form the wide variety of complex nuclei in the Universe? Describing many-nucleon systems from the fundamental theory of quantum chromodynamics has been the greatest challenge in answering this question. The chiral effective field theory description of the nuclear force now makes this possible but requires certain parameters that are not uniquely determined. Defining the nuclear force needs identification of observables sensitive to the different parametrizations. From a measurement of proton elastic scattering on ^{10}C at TRIUMF and ab initio nuclear reaction calculations, we show that the shape and magnitude of the measured differential cross section is strongly sensitive to the nuclear force prescription.
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Scientific data is continually increasing in complexity, variety and size, making efficient visualization and specifically rendering an ongoing challenge. Traditional rasterization-based visualization approaches encounter performance and quality limitations, particularly in HPC environments without dedicated rendering hardware. In this paper, we present OSPRay, a turn-key CPU ray tracing framework oriented towards production-use scientific visualization which can utilize varying SIMD widths and multiple device backends found across diverse HPC resources. This framework provides a high-quality, efficient CPU-based solution for typical visualization workloads, which has already been integrated into several prevalent visualization packages. We show that this system delivers the performance, high-level API simplicity, and modular device support needed to provide a compelling new rendering framework for implementing efficient scientific visualization workflows.
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Proton radii of ^{12-19}C densities derived from first accurate charge changing cross section measurements at 900A MeV with a carbon target are reported. A thick neutron surface evolves from â¼0.5 fm in ^{15}C to â¼1 fm in ^{19}C. The halo radius in ^{19}C is found to be 6.4±0.7 fm as large as ^{11}Li. Ab initio calculations based on chiral nucleon-nucleon and three-nucleon forces reproduce the radii well.
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Differential cross sections of isoscalar and isovector spin-M1 (0(+)â1(+)) transitions are measured using high-energy-resolution proton inelastic scattering at E(p)=295 MeV on (24)Mg, (28)Si, (32)S, and (36)Ar at 0°-14°. The squared spin-M1 nuclear transition matrix elements are deduced from the measured differential cross sections by applying empirically determined unit cross sections based on the assumption of isospin symmetry. The ratios of the squared nuclear matrix elements accumulated up to E(x)=16 MeV compared to a shell-model prediction are 1.01(9) for isoscalar and 0.61(6) for isovector spin-M1 transitions, respectively. Thus, no quenching is observed for isoscalar spin-M1 transitions, while the matrix elements for isovector spin-M1 transitions are quenched by an amount comparable with the analogous Gamow-Teller transitions on those target nuclei.
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The recently confirmed neutron-shell closure at N=32 has been investigated for the first time below the magic proton number Z=20 with mass measurements of the exotic isotopes (52,53)K, the latter being the shortest-lived nuclide investigated at the online mass spectrometer ISOLTRAP. The resulting two-neutron separation energies reveal a 3 MeV shell gap at N=32, slightly lower than for 52Ca, highlighting the doubly magic nature of this nuclide. Skyrme-Hartree-Fock-Bogoliubov and ab initio Gorkov-Green function calculations are challenged by the new measurements but reproduce qualitatively the observed shell effect.
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We derive and compute effective valence-space shell-model interactions from ab initio coupled-cluster theory and apply them to open-shell and neutron-rich oxygen and carbon isotopes. Our shell-model interactions are based on nucleon-nucleon and three-nucleon forces from chiral effective-field theory. We compute the energies of ground and low-lying states, and find good agreement with experiment. In particular, our computed 2(+) states are consistent with N = 14,16 shell closures in (22,24)O, and a weaker N=14 shell closure in (20)C. We find good agreement between our coupled-cluster effective-interaction results with those obtained from standard single-reference coupled-cluster calculations for up to eight valence neutrons.
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OBJECTIVE: To describe a case of uterovesical fistula after cesarean section with symptoms of vulvovaginal discomfort. DESIGN: Case report. SETTING: Department of Urology, Department of Obstetrics and Gynecology, University Hospital and Medical Faculty in Hradec Kralove, Charles University Prague. CONCLUSION: Uterovesical fistula is a rare and unusual complication of cesarean section. Uterovesical fistula is tough to diagnose because of unspecific symptoms. A multidisciplinary approach is necessary for its successful diagnosis and treatment.