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Introduction Docetaxel and erlotinib are registered second-line treatments for wild-type EGFR NSCLC. Previous studies suggested a predictive value of the VeriStrat test in second-line therapy of NSCLC, classifying patients as either VeriStrat good or VeriStrat poor. EMPHASIS-lung aimed at exploring this predictive effect in patients with squamous cell NSCLC. The trial closed prematurely because of low accrual and results from other trials. Our analysis includes an exploratory combined analysis with results from the PROSE trial. Methods EMPHASIS-lung was a randomized phase III multicenter trial exploring the differential effect of second-line erlotinib versus docetaxel on progression-free survival (PFS) in VeriStrat good versus VeriStrat poor patients with squamous cell NSCLC. Results A total of 80 patients were randomized, with 72.5% categorized as VeriStrat good. Patient characteristics were balanced between VeriStrat status and treatment groups. The median PFS times with docetaxel and erlotinib treatment in the VeriStrat good cohort were 4.1 and 1.6 months, respectively, versus 1.9 and 2.1 months, respectively, in the VeriStrat poor cohort. The median overall survival (OS) times with docetaxel and erlotinib treatment in the VeriStrat good cohort were 7.8 and 8.4 months, respectively, and 4.4 and 5.2 months, respectively, in the VeriStrat poor cohort. An additional exploratory analysis was performed; in it, 47 patients from the squamous cell subgroup of PROSE were included in a combined analysis, contributing with 45 PFS and 41 OS events. Conclusions The final analysis of EMPHASIS-lung did not show a differential effect on PFS for erlotinib versus docetaxel stratified by VeriStrat status. Similarly, in the combined analysis, no significant treatment by VeriStrat status interaction was observed (interaction p = 0.24 for PFS and 0.45 for OS, stratified by study). © 2017 International Association for the Study of Lung Cancer

Physical separation of short-lived isotopes produced in heavy-ion-induced fusion reactions is a powerful and well-known method and often applied in investigations of the heaviest elements, called the transactinides ( Z ⩾ 104 ). By extracting these isotopes from a recoil separator, they can be made available for transport to setups located outside the heavily shielded irradiation position such as chemistry setups. This physical preseparation technique overcomes many limitations currently faced in the chemical investigation of transactinides. Here we describe the basic principle using relatively short-lived isotopes of the lighter group 4 elements zirconium (Zr) and hafnium (Hf) used as analogs of the lightest transactinide element, rutherfordium (Rf, element 104). The Zr and Hf isotopes were produced at the LBNL 88-Inch Cyclotron using a cocktail of 18 O and 50 Ti beams and the appropriate targets. Subsequently, the isotopes were physically separated in the Berkeley Gas-filled Separator (BGS) and guided to a Recoil Transfer Chamber (RTC) to transfer them to chemistry setups. The magnetic rigidities of the reaction products in low-pressure helium gas were measured and their identities determined with γ-spectroscopy. Using preseparated isotopes has the advantages of low background and beam plasma free environment for chemistry experiments. The new possibilities that open up for chemical investigations of transactinide elements are described. The method can readily be applied to homologous elements within other groups in the periodic table.

In bombardments of 248Cm with 143.7-146.8 MeV 26Mg ions the nuclides 269Hs and presumably 270Hs were produced. After chemical isolation, Hs atoms were identified by observing genetically linked nuclear-decay chains. Three chains originating from 269Hs confirmed the decay properties observed previously in the decay of 277112. Two chains exhibited the characteristics expected for the new nuclide 270Hs, which was predicted to be a deformed ”doubly magic” nucleus. From the measured $E_\alpha =9.16^{+0.07}_{-0.03}$ MeV an $\alpha$ -decay half-life of 3.6+0.8 -1.4 s was estimated.

The Cryo-Thermochromatographic Separator (CTS) was designed and constructed for rapid, continuous on-line separation and simultaneous detection of highly volatile compounds of short-lived α-decaying isotopes of osmium and hassium (Hs, Z =108). A flowing carrier gas containing the volatile species is passed through a channel formed by two facing rows of 32 α-particle detectors, cooled to form a temperature gradient extending from 247 K at the channel entrance down to 176 K at the exit. The volatile species adsorb onto the SiO 2 -coated detector surfaces at a characteristic deposition temperature and are identified by their observed α-decay energies. The CTS was tested on-line with OsO 4 prepared from 169–173 Os isotopes produced in 118,120 Sn( 56 Fe, 3,4,5n) reactions. An adsorption enthalpy for OsO 4 of −40.2±1.5 kJ/mol on SiO 2 was deduced by comparing the measured deposition distribution with Monte Carlo simulations. This successful result demonstrates that such a system provides a viable means for the first chemical study of hassium—which is expected to be a homologue of osmium—by determining whether it forms a similarly volatile oxide.

The cryosorption method is useful for extracting hydrogen isotopes from a helium gas stream with a small amount of hydrogen isotopes. Therefore, in fusion reactors, this method is expected to be applied for the helium glow discharge exhaust gas processing system and the blanket tritium recovery system. To design these systems, adsorption isotherms for each hydrogen isotope are needed, making it possible to estimate the amount of adsorption in a wide pressure range. The amount of tritium adsorption on molecular sieve 5A, molecular sieve 4A, and activated carbon, which are potential adsorbents in the cryosorption bed, at liquid nitrogen temperature were quantified using the volumetric method, It was found that adsorption isotherms of tritium were also expressed with the two-site Langmuir model and that the obtained isotherms were close to the reported isotherms, the Langmuir coefficients for which were estimated using a reduced mass of hydrogen isotopes.

Author(s): Gregorich, K; Dullman, CE; Loveland, W; Folden, CM; Gates, Jacklyn; Garcia, MA; Sudowe, R; Stavestra, L; Dragojevic, I; Nelson, SL; Pang, GK; Zielinski, PM; Chung, YH; Eichler, R; Schaedel, M; Teurler, A; Yakushev, A; Dvorak, J; Hoffman, DC; Nitsche, H

Author(s): Folden III, C.M.; Nelson, S.L.; Dullmann, Ch.E.; Schwantes, J.M.; Sudowe, R.; Zielinski, P.M.; Gregorich, K.E.; Nitsche, H.; Hoffman, D.C. | Abstract: The excitation function for production of 262Bh in the odd-Z-projectile reaction 208Pb(55Mn,n) has been measured at three projectile energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, 33 decay chains originating from 262Bh and 2 decay chains originating from 261Bh were observed. The measured decay properties are in good agreement with previous reports. The maximum cross section of 540 +180 -150 pb is observed at a lab-frame center-of-target energy of 264.0 MeV and is more than fives times larger than that expected based on previously reported results for production of 262Bh in the analogous even-Z-projectile reaction 209Bi(54Cr,n). Our results indicate that the optimum beam energy in one-neutron-out heavy-ion fusion reactions can be estimated simply using the "Optimum Energy Rule" proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski.

An attempt to confirm production of superheavy elements in the reaction of 48Ca beams with actinide targets has been performed using the 238U(48Ca,3n)283112 reaction. Two 48Ca projectile energies were used, that spanned the energy range where the largest cross sections have been reported for this reaction. No spontaneous fission events were observed. No alpha decay chains consistent with either reported or theoretically predicted element 112 decay properties were observed. The cross section limits reached are significantly smaller than the recently reported cross sections.

Seven {sup 271}Ds decay chains were identified in the bombardment of {sup 208}Pb targets with 311.5- and 314.3-MeV {sup 64}Ni projectiles using the Berkeley Gas-filled Separator. These data, combined with previous results, provide an excitation function for this reaction. From these results, an optimum energy of 321 MeV was estimated for the production of {sup 272}111 in the reaction {sup 208}Pb({sup 65}Cu, n). One decay chain was observed, resulting in a cross section of 1.7{sub -1.4}{sup +3.9} pb. This experiment confirms the discovery of element 111 by the Darmstadt group who used the {sup 209}Bi({sup 64}Ni, n){sup 272}111 reaction.

We report the experimental confirmation of the production of element110. In the bombardment of a 208Pb target with a 309~MeV 64Ni beam, we have observed two chains of time- and position-correlated events. Each chain consisted of the implantation of an evaporation residue followed by the emission of alpha-particles. We attribute these two chains to the decay of 271-110 produced with a cross section of 8.3 (+11/-5.3)pb.

New levels in the neutron-rich ${}^{113}\mathrm{Ru}$ nucleus have been identified by analyzing $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence events following the spontaneous fission of ${}^{252}\mathrm{Cf}$ with the Gammasphere detector array. A rotational band going up to 3.6 MeV is identified and is proposed to be built on the intruder $\ensuremath{\nu}{\mathrm{h}}_{11/2}$ orbital going up to $(31/2)\ensuremath{\Elzxh}.$ A few states of a possible signature partner are also observed.

In April-May, 2001, the previously reported experiment to synthesize element 118 using the $^{208}$Pb($^{86}$Kr,n)$^{293}$118 reaction was repeated. No events corresponding to the synthesis of element 118 were observed with a total beam dose of 2.6 x 10$^{18}$ ions. The simple upper limit cross sections (1 event) were 0.9 and 0.6 pb for evaporation residue magnetic rigidities of 2.00 $T m$ and 2.12 $T m$, respectively. A more detailed cross section calculation, accounting for an assumed narrow excitation function, the energy loss of the beam in traversing the target and the uncertainty in the magnetic rigidity of the Z=118 recoils is also presented. Re-analysis of the primary data files from the 1999 experiment showed the reported element 118 events are not in the original data. The current results put constraints on the production cross section for synthesis of very heavy nuclei in cold fusion reactions., 7 pages, 2 figures. Submitted to EPJA

New level schemes of {sup 141}Ba and {sup 139}Xe are proposed from the analyses of spontaneous-fission gamma data from our {sup 252}Cf spontaneous fission Gammasphere runs of 1995 and 2000. By analogy with the N = 85 even-odd isotones {sup 149}Gd, {sup 147}Sm, and {sup 145}Nd, spins and parities were assigned to the observed excited states in {sup 141}Ba and {sup 139}Xe. It appears that spherical shell model neutron excitations plus octupolephonons are an appropriate basis at the lower end of the bands. Going to higher spins it is clear that the soft rotor involving valence protons as well as neutrons becomes increasingly important in the configurations. Level systematics in the N = 85 even-odd isotones from Gd(Z=64) through Te(Z=52), are discussed. The excitation systematics and smooth trends of the analogous levels support the spin and parity assignment for excited levels observed in {sup 141}Ba and {sup 139}Xe. The level systematics and the comparison with neighboring even-even isotopes indicate that quadrupole and octupole collectivity play roles in {sup 141}Ba and {sup 139}$Xe. From Gd(Z=64) through Te(Z=52), increasing excitation energies of the 13/2{sup +} states and lowering relative intensities of the positive parity bands in the N = 85 even-odd isotones may indicate that the octupole strength is becoming weaker for the isotones when approaching the Z = 50 closed shell.

We identified γ transitions in several neutron‐rich nuclei near 132Sn produced in the spontaneous fission of 252Cf. These are of interest because they can test shell model calculations. These nuclei are 139Ba, 133,135Te, and 121,123Cd. Excited states in neutron‐rich 133Te exhibit four types of particle‐hole bands built on the known 334.3 keV isomer in 133Te. The yrast and near yrast particle‐hole states observed up to 6.2 MeV in 133Te have characteristics quite similar to those in 134Te. The band starting at 5.214 MeV is assigned as a neutron particle‐hole excitation of the double magic core nucleus, 132Sn and is a candidate for a tilted rotor band. Theoretical shell model calculations show good agreement with the experimental states up to 4.3 MeV. The new level scheme of 139Ba includes 11 new transitions and 10 new levels and is compared with the 83‐neutron isotone 135Te. In 135Te, a tilted rotor band, also, is proposed. Excited states built on the 11/2− isomeric states in neutron‐rich 121,123Cd are iden...

Levels in the neutron-rich, odd-mass ${}^{107}\mathrm{Ru}$ nucleus have been reinvestigated with Gammasphere by measuring high-fold, prompt coincidence events following spontaneous fission of ${}^{252}\mathrm{Cf}.$ The ground state band has been extended up to $\frac{27}{2}\ensuremath{\Elzxh}.$ The structure associated with the ${h}_{11/2}$ excitation has been confirmed and extended to higher spin. The ${h}_{11/2}$ band head has been established to lie at 301.8 keV. These results clear up differences between our earlier work and results from another experiment published recently. A new collective band based on a ${9/2}^{\ensuremath{-}}$ level has been identified for the first time. Some distinct features of the level scheme are discussed.