On the adsorption and reactivity of element 114, flerovium.

Flerovium (Fl, element 114) is the heaviest element chemically studied so far. To date, its interaction with gold was investigated in two gas-solid chromatography experiments, which reported two different types of interaction, however, each based on the level of a few registered atoms only. Whereas noble-gas-like properties were suggested from the first experiment, the second one pointed at a volatile-metal-like character. Here, we present further experimental data on adsorption studies of Fl on silicon oxide and gold surfaces, accounting for the inhomogeneous nature of the surface, as it was used in the experiment and analyzed as part of the reported studies. We confirm that Fl is highly volatile and the least reactive member of group 14. Our experimental observations suggest that Fl exhibits lower reactivity towards Au than the volatile metal Hg, but higher reactivity than the noble gas Rn.

[Treatment of patients with metastatic lesions of the long bones]. / Lechenie patsientov s metastaticheskim porazheniem dlinnykh kostei.

OBJECTIVE: To optimize orthopedic care in patients with complicated course of metastatic lesions of the long bones. MATERIAL AND METHODS: There were 201 patients (72 men and 129 women) who underwent orthopedic care for metastatic lesions of the long bones for the period from 2006 to 2019. Breast cancer metastases were diagnosed in 71 (35%) cases, kidney cancer - 56 (28%) patients, prostate cancer - 19 (9%) cases, metastases without a primary identified focus - 15 (8%) patients. Other forms were observed in 40 (20%) patients. All patients were divided into two groups. The first group included 136 patients (68%) who underwent segmental resections with bone replacement. Of these, 100 (73%) patients had secondary lesions of the lower limb bones and 36 (27%) patients with metastatic lesions of the upper limb bones. A threat of pathologic fracture was in 63 (46%) cases, fracture - in 73 (54%) patients. The second group consisted of 65 (32%) patients who underwent immersion osteosynthesis. Of these, 47 (72%) patients had metastatic lesions of the lower limb bones and 18 (28%) patients had secondary lesions of the upper limb bones. A threat of pathologic fracture was in 24 (37%) patients, fracture - in 41 (63%) patients. RESULTS: In the first group, mean surgery time was 140 min, in the second group - 120 min. Mean blood loss in the first group was 600 ml, in the second group - 300 ml. Patients were activated on the 3rd postoperative day in both groups. We analyzed surgical, anatomical and functional results in both groups using MSTS, Watkins and Karnofsky's scales. CONCLUSION: Oncological replacement and osteosynthesis are the main methods of surgical treatment of secondary lesions of the long bones. However, our data emphasize advisability of bone replacement, since this method ensures the most adequate stabilization, pain syndrome relief and long-term improvement of the quality of life.

Spectroscopy along Flerovium Decay Chains: Discovery of

A nuclear spectroscopy experiment was conducted to study α-decay chains stemming from isotopes of flerovium (element Z=114). An upgraded TASISpec decay station was placed behind the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. The fusion-evaporation reactions ^{48}Ca+^{242}Pu and ^{48}Ca+^{244}Pu provided a total of 32 flerovium-candidate decay chains, of which two and eleven were firmly assigned to ^{286}Fl and ^{288}Fl, respectively. A prompt coincidence between a 9.60(1)-MeV α particle event and a 0.36(1)-MeV conversion electron marked the first observation of an excited state in an even-even isotope of the heaviest man-made elements, namely ^{282}Cn. Spectroscopy of ^{288}Fl decay chains fixed Q_{α}=10.06(1) MeV. In one case, a Q_{α}=9.46(1)-MeV decay from ^{284}Cn into ^{280}Ds was observed, with ^{280}Ds fissioning after only 518 µs. The impact of these findings, aggregated with existing data on decay chains of ^{286,288}Fl, on the size of an anticipated shell gap at proton number Z=114 is discussed in light of predictions from two beyond-mean-field calculations, which take into account triaxial deformation.

[Transurethral endopyelotomy using thulium fiber laser].

INTRODUCTION: Transurethral endopyelotomy is an alternative treatment method for short stricture of ureteropelvic junction (UPJ). AIM: to evaluate the efficiency of transurethral thulium laser endopyelotomy. MATERIALS AND METHODS: A total of 94 patients with UPJ obstruction during the period from December 2016 to December 2018 were prospectively enrolled in the study. Pelvic size did not exceed 3 cm in 31 patients, and it was in the range from 3 to 4 cm and more than 4 cm in 35 and 28 cases, respectively. Depending on the treatment, all patients were divided into 2 groups. The main group included 48 patients who underwent retrograde thulium fiber laser endopyelotomy. In the control group (n = 46), patients underwent Anderson-Hynes laparoscopic pyeloplasty. In the main group, there were significantly more patients with more preserved ipsilateral kidney function, with short (less than 1 cm) and recurrent UPJ strictures and less severe hydronephrosis compared to the control group. In addition, there were no patients with crossing vessel in the main group. Postoperatively, an internal stent of 6-8 Fr was put in all patients for a period of 6-8 weeks. After stent removal, all patients underwent a follow-up examination, including an ultrasound examination and, if pelvic size was more than 3 cm, contrast-enhanced CT-urography was performed. RESULTS: In all patients, after stent removal, a decrease in the pelvic size was noted. The operation time in the main and control group was 24+/-14 minutes and 82+/-26 minutes, respectively. In all cases, ureteropyeloscopy was performed prior to laparoscopy to determine the exact length of stricture and to exclude narrowing of other parts of the ureter. After follow-up of 24 months, an examination in 36 patients of the main group and 29 patients of the control group was performed. There was 1 recurrence after laparoscopic pyeloplasty and 1 recurrence after endopyelotomy. In other patients of both groups, there were neither stricture, nor impaired renal function. CONCLUSION: The first experience of using a thulium fiber laser for transurethral endoscopic treatment of UPJ obstruction is presented in the article. Indications for the transurethral thulium endopyelotomy are the presence of primary or secondary UPJ obstruction (with a decrease in kidney function by no more than 40%), length of up to 1 cm, absence of an additional vessel and pelvic dilatation of no more than 4 cm.

Strong Neutron Pairing in core+4n Nuclei.

The emission of neutron pairs from the neutron-rich N=12 isotones ^{18}C and ^{20}O has been studied by high-energy nucleon knockout from ^{19}N and ^{21}O secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay ^{19}N(-1p)^{18}C^{*}→^{16}C+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a ^{14}C core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay ^{21}O(-1n)^{20}O^{*}→^{18}O+n+n, attributed to its formation through the knockout of a deeply bound neutron that breaks the ^{16}O core and reduces the number of pairs.

Quasifree (p, 2p) Reactions on Oxygen Isotopes: Observation of Isospin Independence of the Reduced Single-Particle Strength.

Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the R^{3}B/LAND setup with incident beam energies in the range of 300-450 MeV/u. The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type ^{A}O(p,2p)^{A-1}N have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry.

Role of the Δ Resonance in the Population of a Four-Nucleon State in the

The ^{54}Fe nucleus was populated from a ^{56}Fe beam impinging on a Be target with an energy of E/A=500 MeV. The internal decay via γ-ray emission of the 10^{+} metastable state was observed. As the structure of this isomeric state has to involve at least four unpaired nucleons, it cannot be populated in a simple two-neutron removal reaction from the ^{56}Fe ground state. The isomeric state was produced in the low-momentum (-energy) tail of the parallel momentum (energy) distribution of ^{54}Fe, suggesting that it was populated via the decay of the Δ^{0} resonance into a proton. This process allows the population of four-nucleon states, such as the observed isomer. Therefore, it is concluded that the observation of this 10^{+} metastable state in ^{54}Fe is a consequence of the quark structure of the nucleons.

New Short-Lived Isotope

Two short-lived isotopes ^{221}U and ^{222}U were produced as evaporation residues in the fusion reaction ^{50}Ti+^{176}Yb at the gas-filled recoil separator TASCA. An α decay with an energy of E_{α}=9.31(5) MeV and half-life T_{1/2}=4.7(7) µs was attributed to ^{222}U. The new isotope ^{221}U was identified in α-decay chains starting with E_{α}=9.71(5) MeV and T_{1/2}=0.66(14) µs leading to known daughters. Synthesis and detection of these unstable heavy nuclei and their descendants were achieved thanks to a fast data readout system. The evolution of the N=126 shell closure and its influence on the stability of uranium isotopes are discussed within the framework of α-decay reduced width.

48Ca+249Bk fusion reaction leading to element Z = 117: long-lived α-decaying 270Db and discovery of 266Lr.

The superheavy element with atomic number Z=117 was produced as an evaporation residue in the (48)Ca+(249)Bk fusion reaction at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. The radioactive decay of evaporation residues and their α-decay products was studied using a detection setup that allowed measuring decays of single atomic nuclei with half-lives between sub-µs and a few days. Two decay chains comprising seven α decays and a spontaneous fission each were identified and are assigned to the isotope (294)117 and its decay products. A hitherto unknown α-decay branch in (270)Db (Z = 105) was observed, which populated the new isotope (266)Lr (Z = 103). The identification of the long-lived (T(1/2) = 1.0(-0.4)(+1.9) h) α-emitter (270)Db marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an "island of stability."

Spectroscopy of element 115 decay chains.

A high-resolution α, x-ray, and γ-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated α-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z=115. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z>112. Comprehensive Monte Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.

Coulomb excitation of 104Sn and the strength of the 100Sn shell closure.

A measurement of the reduced transition probability for the excitation of the ground state to the first 2+ state in 104Sn has been performed using relativistic Coulomb excitation at GSI. 104Sn is the lightest isotope in the Sn chain for which this quantity has been measured. The result is a key point in the discussion of the evolution of nuclear structure in the proximity of the doubly magic nucleus 100Sn. The value B(E2; 0+ → 2+) = 0.10(4) e2b2 is significantly lower than earlier results for 106Sn and heavier isotopes. The result is well reproduced by shell model predictions and therefore indicates a robust N = Z = 50 shell closure.

Chronology of particle emission from the E/A=61 MeV 36Ar+27Al reaction.

The emission time chronology of neutrons, protons, and deuterons from the E/A=61 MeV 36Ar+27Al reaction is deduced from two-particle correlation functions.