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Fachkräftemangel und Nachwuchssorgen, dazu die Corona-Pandemie, die die Arbeitswelt gehörig durcheinanderwirbelte – die Herausforderungen für die Entsorgungs- und Recyclingbranche sind enorm. Dabei gehört der Umweltsektor zur kritischen Infrastruktur, besitzt somit gesellschaftspolitisch höchste Bedeutung. Doch vor allem für die mittelständischen Unternehmen in der Umweltwirtschaft wird es schwer, sind Experten überzeugt.

A novel combination of advanced gas-chromatography and detection systems coupled to a buffer-gas cell was characterized on-line to allow gas-phase chemical studies of accelerator-produced short-lived α -decaying mercury, francium, and astatine isotopes. These were produced in 40Ar- and 48Ca-induced nuclear fusion–evaporation reactions, subsequently isolated in the recoil separators MARS at Texas A&M University, USA, and TASCA at GSI Darmstadt, Germany, before being thermalized in a buffer-gas-stopping cell. From the latter, the nuclear reaction products were extracted into gas-phase chromatographic systems, suitable for registering α -decaying short-lived radionuclides, such as isotopes of superheavy elements. Efficiencies of 21(3)% for 204-209Fr were reached for the extraction into the optimized miniCOMPACT gas-chromatography setup, indicating that this technique enables the identification of isotopes of volatile as well as non-volatile elements. These studies guide the path towards chemical investigations of superheavy elements beyond flerovium, which are out of reach with currently used setups.

Gas catchers are widely used to thermalize nuclear reaction products and subsequently extract them for precision measurements. However, impurities in the inert stopping gas can chemically react with the ions and thus influence the extraction efficiency. So far, chemical reactions in the gas-catcher have not been investigated in detail. Therefore, we are currently building a new setup to develop Chemical Isobaric SEparation (CISE) with the aim to understand the chemistry inside the gas-catcher and to explore its potential as a new technique for separation of isobars. In this paper, we give a short description of the setup together with the ion transportation studies performed via ion-optics simulations.

Physics letters / B 758, 407 - 411 (2016). doi:10.1016/j.physletb.2016.04.059, Published by North-Holland Publ., Amsterdam

Atoms 10(2), 48 (2022). doi:10.3390/atoms10020048, Published by MDPI, Basel

Horner’s syndrome is a clinical triad composed of ptosis, miosis, and facial anhidrosis. Overall, this complication is rare but well-documented in the obstetric population receiving labor epidural analgesia, which usually follows a relatively benign transient course. Less commonly, few cases of Horner’s syndrome have been reported in the pediatric population following surgical correction of scoliosis with epidural placement. We present a rare case of a pediatric patient that developed Horner’s syndrome secondary to epidural anesthesia following surgical correction of scoliosis.

Hyperkalemic periodic paralysis (HyperPP) is the rarer of two forms of potassium-associated familial paralysis characterized by episodic flaccid weakness secondary to an increase in serum potassium. The rarest of the dyskalemic paralyzes, the incidence of the hyperkalemic variety has been estimated to be 1:500,000. Known precipitating factors are potassium intake, fasting, hypothermia, infection, stress, rest after exercise, and anesthesia. The key to successful management is avoidance of triggering factors, vigilant monitoring of potassium, and aggressive treatment of hyperkalemia. We present a case of a 41-year-old male with HyperPP who underwent general anesthesia successfully.

11 pags., 10 figs., 2 tabs., The coherent coupling between a quartz electro-mechanical resonator at room temperature and trapped ions in a 7 T Penning trap has been demonstrated for the first time. The signals arising from the coupling remain for integration times in the orders of seconds. From the measurements carried out, we demonstrate that the coupling allows detecting the reduced-cyclotron frequency (ν +) within times in the order of the decay-time constant of the energized resonator (below 10 ms), regardless of the data-acquisition time-window in use, and providing an improved resolution compared to conventional electronic detection schemes. A resolving power ν +/Δν + = 2.4 107 has been reached in single measurements. In this publication we present the first results, emphasizing the novel features of the quartz resonator as fast non-destructive ion-trap detector together with different ways to analyze the data and considering aspects like precision, resolution and sensitivity., We acknowledge support from the Spanish MCINN through the projects FPA2015-67694-P, and PID2019-104093GB-I00/AEI/10.01339/501100011033, and contract number PTA2018-016573-I, from the Spanish Ministry of Education through PhD fellowship FPU17/02596, and from the University of Granada ‘Plan propio-Programa de Intensificacion de la Investigacion’, project PP2017-PRI.I-04 and ‘Laboratorios ´ Singulares 2020’. The construction of the facility was supported by the European Research Council (contract No. 278648-TRAPSENSOR), the above-mentioned project FPA2015-67694-P, project FPA2012-32076, and the infrastructure projects UNGR10-1E-501, UNGR13-1E-1830 and EQC2018- 005130-P (MICINN/FEDER/Universidad de Granada), and the infrastructure projects IE-5713 and IE2017-5513 (Junta de Andalucía-FEDER). MB and SL acknowledge financial support by the German BMBF in the project 05P18UMFN1. JJGR acknowledges support from CSIC Technology Platform PTI-001 and CAM PRICYT project QUITEMAD+CM S2013-ICE2801.

© 2019 Fusion-evaporation reactions with the doubly magic projectile 48 Ca were used to access neutron-deficient nuclei around neptunium at the velocity filter SHIP, and investigated using the COMPASS decay spectroscopy station. With the use of digital electronics, several isotopes produced via neutron, proton, and α evaporation channels were identified by establishing correlated α-decay chains with short-lived sub-μs members. Data are given on decay chains stemming from 225,226 Np, 225 U, and 222,223 Pa. New information on the isotopes 225,226 Np and 222 Pa was obtained. Production cross sections of nuclei in the region using a variety of projectiles are discussed. The measured production cross-sections indicate that the usual advantages of using 48 Ca as a beam projectile to produce nuclei Z>100 are absent in the production of these slightly lighter nuclei. ispartof: NUCLEAR PHYSICS A vol:987 pages:337-349 status: published

The precise determination of atomic and nuclear properties such as masses, differential charge radii, nuclear spins, electromagnetic moments and the ionization potential of the actinides has been extended to the late actinides in recent years. In particular, laser spectroscopy and mass spectrometry have reached the region of heavy actinides that can only be produced only at accelerator facilities. The new results provide deeper insight into the impact of relativistic effects on the atomic structure and the evolution of nuclear shell effects around the deformed neutron shell closure at N = 152. All these experimental activities have also opened the door to extend such measurements to the transactinide elements in the near future. This contribution summarizes recent achievements in Penning trap mass spectrometry and laser spectroscopy of the late actinides and addresses future perspectives.

The precise determination of atomic and nuclear properties such as masses, differential charge radii, nuclear spins and electromagnetic moments of exotic nuclides has recently been extended to the region of the heaviest elements. To this end, ion trap-based techniques and laser spectroscopy methods have been employed to provide information complementary to that obtained by nuclear spectroscopy. This enables more detailed studies of the atomic and nuclear structure of these exotic nuclides far from stability. This contribution summarizes some of the recent achievements and addresses future perspectives for measurements on even heavier elements.

The treatment for aortic stenosis is evolving rapidly with new developments in transcatheter aortic valve replacement (TAVR). While the procedure was initially performed under general anesthesia with invasive monitoring and transesophageal echocardiography, recent trends have shifted toward less invasive strategies. Transfemoral TAVRs are frequently performed under sedation; however, TAVRs using alternative access sites, such as the subclavian artery, are typically performed under general anesthesia. This case series describes 3 patients who underwent subclavian TAVR under combined pectoralis and interscalene blocks. All patients tolerated the procedure without complication, requiring no airway manipulation and minimal postoperative analgesia.

Online gas-solid adsorption studies with single atom quantities of Hg, Tl, and Pb on SiO$_{2}$ and Au surfaces were carried out using short-lived radioisotopes with half-lives in the range of 4-49 s. This is a model study to measure adsorption enthalpies of superheavy elements Cn, Nh, and Fl. The short-lived isotopes were produced and separated by the gas-filled recoil separator TASCA at GSI. The products were stopped in He gas, and flushed into gas chromatography columns made of Si detectors whose surfaces were covered by SiO$_{2}$ or Au. The short-lived Tl and Pb were successfully measured by the Si detectors with the SiO$_{2}$ surface at room temperature. On the other hand, the Hg did not adsorb on the SiO$_{2}$ surface, but adsorbed on the Au surface. The results demonstrated that the adsorption properties of short-lived Hg, Tl, and Pb could be studied with this setup, and that this method is applicable to the experiment for Cn, Nh, and Fl., 半減期4$\sim$49秒の短寿命同位体を用いて、水銀(Hg), タリウム(Tl), 鉛(Pb)の単一原子レベルでのSiO$_{2}$及びAu表面への固体吸着挙動をオンライン気相実験により調べた。超重元素Cn, Nh, Flの吸着エンタルピー測定のためのモデル実験として実施した。短寿命同位体はドイツ重イオン研究所の反跳核分離装置TASCAを用いて生成・分離した。生成核はヘリウムガス中に捕集された後、SiO$_{2}$あるいはAuで表面を覆われたSi検出器で作製されたガスクロマトグラフィーカラムへと導入した。短寿命Tl及びPb同位体は室温においてSiO$_{2}$表面に吸着し、Si検出器で測定することに成功した。一方、HgはSiO$_{2}$表面には吸着せず、Au表面に吸着した。この結果より、本実験のセットアップを用いることで短寿命Hg, Tl, Pb同位体の吸着特性を調べることができると証明され、この手法がCn, Nh, Flの実験にも適用できることが確認された。

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 fur 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.

The interest to perform laser spectroscopy in the heaviest elements arises from the strong impact of relativistic effects, electron correlations and quantum electrodynamics on their atomic structure. Once this atomic structure is well understood, laser spectroscopy also provides access to nuclear properties such as spins, mean square charge radii and electromagnetic moments in a nuclear-model independent way. This is of particular interest for the heaviest actinides around $N = 152$, a region of shell stabilized deformed nuclei. The experimental progress of laser spectroscopy in this region benefitted from continuous methodological and technical developments such as the introduction of buffer-gas-stopping techniques that enabled the access to ever more exotic nuclei far-off stability. The key challenges faced in this endeavor are small yields, nuclides with rather short half-lives and the need to search for atomic transitions in a wide spectral range guided by theoretical predictions. This paper describes the basics of the most common experimental methods and discusses selected recent results on the atomic and nuclear properties of the actinides up to nobelium where pioneering experiments were performed at the GSI Helmholtzzentrum f\"ur Schwerionenforschung in Darmstadt, Germany., Comment: https://www.sciencedirect.com/science/article/abs/pii/S0146641020300818

In two recent papers by Pore et al. and Khuyagbaatar et al., discovery of the new isotope $^{244}\mathrm{Md}$ was reported. The decay data, however, are conflicting. While Pore et al. report two isomeric states decaying by $\ensuremath{\alpha}$ emission with ${E}_{\ensuremath{\alpha}}(1)=8.66(2)\text{ }\text{ }\mathrm{MeV}$, ${T}_{1/2}(1)={0.4}_{\ensuremath{-}0.1}^{+0.4}\text{ }\text{ }\mathrm{s}$ and ${E}_{\ensuremath{\alpha}}(2)=8.31(2)\text{ }\text{ }\mathrm{MeV}$, ${T}_{1/2}(2)\ensuremath{\approx}6\text{ }\text{ }\text{ }\mathrm{s}$, Khuyagbaatar et al. [Phys. Rev. Lett. 125, 142504 (2020).] report only a single transition with a broad energy distribution of ${E}_{\ensuremath{\alpha}}=(8.73--8.86)\text{ }\text{ }\mathrm{MeV}$ and ${T}_{1/2}={0.30}_{\ensuremath{-}0.09}^{+0.19}\text{ }\text{ }\mathrm{s}$. The data published in Pore et al. are very similar to those published for $^{245m}\mathrm{Md}$ [${E}_{\ensuremath{\alpha}}=8.64(2)$, 8.68(2) MeV, ${T}_{1/2}={0.35}_{\ensuremath{-}0.16}^{+0.23}\text{ }\text{ }\mathrm{s}$ [V. Ninov, F. P. He\ss{}berger, S. Hofmann, H. Folger, G. M\"unzenberg, P. Armbruster, A. V. Yeremin, A. G. Popeko, M. Leino, and S. Saro, Z. Phys. A 356, 11 (1996).] ]. Therefore, we compare the data presented for $^{244}\mathrm{Md}$ in Pore et al. with those reported for $^{245}\mathrm{Md}$ in Ninov et al. and also in Khuyagbaatar et al. We conclude that the data presented in Pore et al. shall be attributed to $^{245}\mathrm{Md}$ with small contributions (one event each) from $^{245}\mathrm{Fm}$ and probably $^{246}\mathrm{Md}$.

Development and guidance of dosing schemes in children have been supported by physiology‐based pharmacokinetic (PBPK) modeling for many years. PBPK models are built on a generic basis, where compound‐ and system‐specific parameters are separated and can be exchanged, allowing the translation of these models from adults to children by accounting for physiological differences. Owing to these features, PBPK modeling is a valuable approach to support clinical decision making for dosing in children. In this analysis, we evaluate pediatric PBPK models for 10 small‐molecule compounds that were applied to support clinical decision processes at Bayer for their predictive power in different age groups. Ratios of PBPK‐predicted to observed PK parameters for the evaluated drugs in different pediatric age groups were estimated. Predictive performance was analyzed on the basis of a 2‐fold error range and the bioequivalence range (ie, 0.8 ≤ predicted/observed ≤ 1.25). For all 10 compounds, all predicted‐to‐observed PK ratios were within a 2‐fold error range (n = 27), with two‐thirds of the ratios within the bioequivalence range (n = 18). The findings demonstrate that the pharmacokinetics of these compounds was successfully and adequately predicted in different pediatric age groups. This illustrates the applicability of PBPK for guiding dosing schemes in the pediatric population.

A search for production of the superheavy elements with atomic numbers 119 and 120 was performed in the 50Ti+249Bk and 50Ti+249Cf fusion-evaporation reactions, respectively, at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. Over four months of irradiation, the 249Bk target partially decayed into 249Cf, which allowed for a simultaneous search for both elements. Neither was detected at cross-section sensitivity levels of 65 and 200 fb for the 50Ti+249Bk and 50Ti+249Cf reactions, respectively, at a midtarget beam energy of Elab=281.5 MeV. The nonobservation of elements 119 and 120 is discussed within the concept of fusion-evaporation reactions including various theoretical predictions on the fission-barrier heights of superheavy nuclei in the region of the island of stability. peerReviewed

Hyperfine interactions 241(1), 46 (2020). doi:10.1007/s10751-020-01708-0, Published by Springer Science + Business Media B.V, Dordrecht [u.a.]

The electron-capture decay followed by a prompt fission process was searched for in the hitherto unknown most neutron-deficient Md isotope with mass number 244. Alpha decay with $\ensuremath{\alpha}$-particle energies of 8.73--8.86 MeV and with a half-life of ${0.30}_{\ensuremath{-}0.09}^{+0.19}\text{ }\text{ }\mathrm{s}$ was assigned to $^{244}\mathrm{Md}$. No fission event with a similar half-life potentially originating from spontaneous fissioning of the short-lived electron-capture decay daughter $^{244}\mathrm{Fm}$ was observed, which results in an upper limit of 0.14 for the electron-capture branching of $^{244}\mathrm{Md}$. Two groups of fission events with half-lives of ${0.9}_{\ensuremath{-}0.3}^{+0.6}\text{ }\text{ }\mathrm{ms}$ and ${5}_{\ensuremath{-}2}^{+3}\text{ }\text{ }\mathrm{ms}$ were observed. The ${0.9}_{\ensuremath{-}0.3}^{+0.6}\text{ }\text{ }\mathrm{ms}$ activity was assigned to originate from the decay of $^{245}\mathrm{Md}$. The origin of eight fission events resulting in a half-life of ${5}_{\ensuremath{-}2}^{+3}\text{ }\text{ }\mathrm{ms}$ could not be unambiguously identified within the present data while the possible explanation has to invoke previously unseen physics cases.

Spontaneous fission properties of the isotopes $^{255}\mathrm{Rf}$, $^{256}\mathrm{Rf}$, and $^{258}\mathrm{Rf}$ produced in the reactions $^{50}\mathrm{Ti}+^{207}\mathrm{Pb}$, $^{50}\mathrm{Ti}+^{208}\mathrm{Pb}$, and $^{50}\mathrm{Ti}+^{209}\mathrm{Bi}$ were studied. The method of time and position correlations was used to identify spontaneous fission events. The correction to the energy deficit in measured total kinetic energy (TKE) determined on the basis of a study of $^{252}\mathrm{No}$ was applied to evaluate the $\overline{\mathrm{TKE}}$ of investigated rutherfordium isotopes. A signature which we assigned tentatively to bimodal fission was observed in TKE distributions of $^{255}\mathrm{Rf}$ and $^{256}\mathrm{Rf}$. Two new high-K isomeric states in $^{255}\mathrm{Rf}$ were identified by ER-CE-(CE)-$\ensuremath{\alpha}$/SF correlation search, with half-lives of ${38}_{\ensuremath{-}7}^{+12}$ and ${15}_{\ensuremath{-}4}^{+6}$ $\ensuremath{\mu}\mathrm{s}$ at excitation energies 1150--1450 and 900--1200 keV, respectively. Including those metastable states a tentative partial level scheme was proposed.

Hyperfine interactions 241(1), 49 (2020). doi:10.1007/s10751-019-1691-7, Published by Springer Science + Business Media B.V, Dordrecht [u.a.]

An upgraded TASISpec setup, with the addition of a veto DSSD and the new Compex detector-germanium array, has been employed with the gas-filled recoil separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt, to study flerovium (element 114) decay chains. The detector upgrades along with development of new analytical techniques have improved the sensitivity of the TASISpec setup for measuring α-photon coincidences. These improvements have been assessed with test reactions. The reaction 48Ca+206,207Pb was used for verification of experimental parameters such as transmission to implantation DSSD and target-segment to α-decay correlations. The reaction 48Ca+ nat Hf was used to produce several short-lived nuclei with multiple-α decay chains to investigate pile-up event deconvolution.

Hyperfine interactions 241(1), 35 (2020). doi:10.1007/s10751-019-1689-1, Published by Springer Science + Business Media B.V, Dordrecht [u.a.]

A compact silicon detector array with high spatial granularity and fast, fully digital data recording has been developed and commissioned for the investigation of heavy and superheavy nuclear species. The detector array can be combined in close geometry with large volume germanium detectors. It offers comprehensive particle and photon coincidence and correlation spectroscopy by highly efficient evaporation residue, α , γ , conversion electron and X-ray detection supported by the high granularity of the implantation chip. Access to fast decay events in the sub-microsecond region is made possible by the fast timing properties of the digital signal processing. A novel Si-chip support design allows direct cooling of the Si-chips and short signal transport. The compact and modular mechanical design equipped with a standard flange facilitates its transport and connection to different separators at different ion beam facilities. After initial tests, first α - γ coincidence spectroscopy experiments have been performed at the LISE separator of GANIL in Caen, France, in FULIS (velocity filter) mode and at the velocity filter SHIP of GSI in Darmstadt, Germany.

The isotopic distribution of nuclei produced in the 50Ti + 249Cf reaction has been studied at the gas-filled recoil separator TASCA at GSI Darmstadt, which separates ions according to differences in magnetic rigidity. The bombardment was performed at an energy around the Bass barrier and with the TASCA magnetic fields set for collecting fusion-evaporation reaction products. Fifty-three isotopes located “north-east” of 208Pb were identified as recoiling products formed in non-fusion channels of the reaction. These recoils were implanted with energies in two distinct ranges; besides one with higher energy, a significant low-energy contribution was identified. The latter observation was not expected to occur according to kinematics of the known types of reactions, namely quasi-elastic, multi-nucleon transfer, deep-inelastic collisions or quasifission. The present observations are discussed within the framework of two-body kinematics passing through the formation of a composite system.

The article focuses on the scientists' efforts in the past decade to find the world's heaviest element. It refers to the discovery of oganesson in 2006 by a Russian-American research team using a particle accelerator in Dubna, Russia. It also explores the island of stability describing special arrangements of protons and neutrons that makes an element stable.