Deformation versus Sphericity in the Ground States of the Lightest Gold Isotopes

The changes in mean-squared charge radii of neutron-deficient gold nuclei have been determined using the in-source, resonance-ionization laser spectroscopy technique, at the ISOLDE facility (CERN). From these new data, nuclear deformations are inferred, revealing a competition between deformed and spherical configurations. The isotopes ^{180,181,182}Au are observed to possess well-deformed ground states and, when moving to lighter masses, a sudden transition to near-spherical shapes is seen in the extremely neutron-deficient nuclides, ^{176,177,179}Au. A case of shape coexistence and shape staggering is identified in ^{178}Au which has a ground and isomeric state with different deformations. These new data reveal a pattern in ground-state deformation unique to the gold isotopes, whereby, when moving from the heavy to light masses, a plateau of well-deformed isotopes exists around the neutron midshell, flanked by near-spherical shapes in the heavier and lighter isotopes-a trend hitherto unseen elsewhere in the nuclear chart. The experimental charge radii are compared to those from Hartree-Fock-Bogoliubov calculations using the D1M Gogny interaction and configuration mixing between states of different deformation. The calculations are constrained by the known spins, parities, and magnetic moments of the ground states in gold nuclei and show a good agreement with the experimental results.

Isomeric Excitation Energy for ^{99}In^{m} from Mass Spectrometry Reveals Constant Trend Next to Doubly Magic ^{100}Sn

The excitation energy of the 1/2^{-} isomer in ^{99}In at N=50 is measured to be 671(37) keV and the mass uncertainty of the 9/2^{+} ground state is significantly reduced using the ISOLTRAP mass spectrometer at ISOLDE/CERN. The measurements exploit a major improvement in the resolution of the multireflection time-of-flight mass spectrometer. The results reveal an intriguing constancy of the 1/2^{-} isomer excitation energies in neutron-deficient indium that persists down to the N=50 shell closure, even when all neutrons are removed from the valence shell. This trend is used to test large-scale shell model, ab initio, and density functional theory calculations. The models have difficulties describing both the isomer excitation energies and ground-state electromagnetic moments along the indium chain.

Statistical modelling of COVID-19 pandemic development applying branching processes

In this paper, a statistical model for COVID-19 infection dynamics is described, using only the observed daily statistics of infected individuals. For this purpose, two special classes of branching processes without or with an immigration component are considered. These models are intended to estimate the main parameter of the infection and to give a prediction of the mean value of the non-observed population of the infected individuals. This is a serious advantage in comparison with other more complicated models where the officially reported data are not sufficient for estimation of the model parameters. The model is applied for different regions in the world and the corresponding parameters of the infection dynamics are estimated.

MULTIPLE INTERVAL DEBULKING SURGERY IN RECURRENT UTERINE SARCOMA (CASE REPORT)

We report a case of a 61-year-old woman, who had been suffering from multiple relapses of uterine sarcoma treated by multiple cytoreduction operations. During the observation period there were performed 13 surgical interventions. As a result of operations, together with the removal of more than 60 liters of tumor volume, the following were performed: extirpation of the uterus with ovaries, right colectomy, resection of the small intestine four times, resection of the sigmoid colon, resection of the duodenum, peritonectomy, cholecystectomy, appendectomy, 2 cycles of adjuvant chemotherapy and Hyperthermic intraperitoneal chemotherapy procedure. During this entire period, with interruptions for hospital treatment, the patient works as a teacher, quality of life remains satisfactory. Patient observation continues, according to the computed tomography control (last time 02.12.2021) there are no signs of tumor relapse. 64 months have passed since the first clinical relapse. The overall survival rate is 69 months and it has already exceeded the theoretically unattainable 5 years from the onset of the disease. Cytoreductive surgery in patients with chemo- and radioresistant tumors of the abdominal cavity is the only effective method of treatment of this group of patients in addition to symptomatic therapy. Repeated early optimal cytoreduction with the maximum possible removal of all detected tumor mass and restoration of anatomical or functional integrity of the affected organs can reduce the likelihood of tumor cachexia, intoxication, anemia, thrombosis and hemorrhage, edema and dysfunction of the digestive and urinary systems. This prolongs life expectancy and increases its quality in patients with second and more uterine sarcoma relapse.

Laser Spectroscopy of Neutron-Rich ^{207,208}Hg Isotopes: Illuminating the Kink and Odd-Even Staggering in Charge Radii across the N=126 Shell Closure

The mean-square charge radii of ^{207,208}Hg (Z=80, N=127, 128) have been studied for the first time and those of ^{202,203,206}Hg (N=122, 123, 126) remeasured by the application of in-source resonance-ionization laser spectroscopy at ISOLDE (CERN). The characteristic kink in the charge radii at the N=126 neutron shell closure has been revealed, providing the first information on its behavior below the Z=82 proton shell closure. A theoretical analysis has been performed within relativistic Hartree-Bogoliubov and nonrelativistic Hartree-Fock-Bogoliubov approaches, considering both the new mercury results and existing lead data. Contrary to previous interpretations, it is demonstrated that both the kink at N=126 and the odd-even staggering (OES) in its vicinity can be described predominately at the mean-field level and that pairing does not need to play a crucial role in their origin. A new OES mechanism is suggested, related to the staggering in the occupation of the different neutron orbitals in odd- and even-A nuclei, facilitated by particle-vibration coupling for odd-A nuclei.

First Glimpse of the N=82 Shell Closure below Z=50 from Masses of Neutron-Rich Cadmium Isotopes and Isomers

We probe the N=82 nuclear shell closure by mass measurements of neutron-rich cadmium isotopes with the ISOLTRAP spectrometer at ISOLDE-CERN. The new mass of ^{132}Cd offers the first value of the N=82, two-neutron shell gap below Z=50 and confirms the phenomenon of mutually enhanced magicity at ^{132}Sn. Using the recently implemented phase-imaging ion-cyclotron-resonance method, the ordering of the low-lying isomers in ^{129}Cd and their energies are determined. The new experimental findings are used to test large-scale shell-model, mean-field, and beyond-mean-field calculations, as well as the ab initio valence-space in-medium similarity renormalization group.

Precision Mass Measurements of ^{58-63}Cr: Nuclear Collectivity Towards the N=40 Island of Inversion

The neutron-rich isotopes ^{58-63}Cr were produced for the first time at the ISOLDE facility and their masses were measured with the ISOLTRAP spectrometer. The new values are up to 300 times more precise than those in the literature and indicate significantly different nuclear structure from the new mass-surface trend. A gradual onset of deformation is found in this proton and neutron midshell region, which is a gateway to the second island of inversion around N=40. In addition to comparisons with density-functional theory and large-scale shell-model calculations, we present predictions from the valence-space formulation of the ab initio in-medium similarity renormalization group, the first such results for open-shell chromium isotopes.

Binding Energy of ^{79}Cu: Probing the Structure of the Doubly Magic ^{78}Ni from Only One Proton Away

The masses of the neutron-rich copper isotopes ^{75-79}Cu are determined using the precision mass spectrometer ISOLTRAP at the CERN-ISOLDE facility. The trend from the new data differs significantly from that of previous results, offering a first accurate view of the mass surface adjacent to the Z=28, N=50 nuclide ^{78}Ni and supporting a doubly magic character. The new masses compare very well with large-scale shell-model calculations that predict shape coexistence in a doubly magic ^{78}Ni and a new island of inversion for Z<28. A coherent picture of this important exotic region begins to emerge where excitations across Z=28 and N=50 form a delicate equilibrium with a spherical mean field.

Precision Mass Measurements of ^{129-131}Cd and Their Impact on Stellar Nucleosynthesis via the Rapid Neutron Capture Process

Masses adjacent to the classical waiting-point nuclide ^{130}Cd have been measured by using the Penning-trap spectrometer ISOLTRAP at ISOLDE/CERN. We find a significant deviation of over 400 keV from earlier values evaluated by using nuclear beta-decay data. The new measurements show the reduction of the N=82 shell gap below the doubly magic ^{132}Sn. The nucleosynthesis associated with the ejected wind from type-II supernovae as well as from compact object binary mergers is studied, by using state-of-the-art hydrodynamic simulations. We find a consistent and direct impact of the newly measured masses on the calculated abundances in the A=128-132 region and a reduction of the uncertainties from the precision mass input data.

Probing the N=32 Shell Closure below the Magic Proton Number Z=20: Mass Measurements of the Exotic Isotopes ^{52,53}K

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.

[A modified method of hepaticocholedochojejunal anastomosis]

"Declive" latero-terminal and latero-lateral hepaticocholedocho-jejunoanastomosis with a loop of the small intestine isolated by the Roux method was carried out in 6 patients (5 females and 1 male) according to absolute indications. In this type of anastomosis, the longitudinal incision in the hepaticocholedochus is made not on the midline but latero-dorsally on its right supraduodenal circumference. The anastomosis is formed by means of a modified suture or a suture commonly used for bilio-digestive anastomoses; the needle is inserted through the wall of the bile duct 2-2.5 mm from the border of its opening and the sutures are placed at a similar distance from one another, the seromusculo-submucous sutures are applied 6-7 mm from the edge of the opening and at a distance of 3-3.5 mm from one another. Comparison with patients in whom heapticocholedochojejunoanastomosis was established by the routine method showed the results to be better in the modified method.

[Traumatic aneurysm of facial artery]

Traumatic aneurysms of the peripheral arteries are observed exceptionally rarely. With the localization in the maxillofacial region it presents a diagnostic and therapeutic problem. The authors report the successful treatment of a patient with traumatic aneurysm of facial artery, directing the attention to the necessity of a diagnostic puncture in case of traumatic swelling with pulsations.