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Abstract: It is still a matter of debate whether functional cerebral asymmetries (FCA) of many cognitive processes are more pronounced in men than in women. Some evidence suggests that the apparent reduction in women's FCA is a result of the fluctuating levels of gonadal steroid hormones over the course of the menstrual cycle, making their FCA less static than for men. The degree of lateralization has been suggested to depend on interhemispheric communication that may be modulated by gonadal steroid hormones. Here, we employed visual-evoked EEG potentials to obtain a direct measure of interhemispheric communication during different phases of the menstrual cycle. The interhemispheric transfer time (IHTT) was estimated from the interhemispheric latency difference of the N170 component of the visual-evoked potential from either left or right visual field presentation. Nineteen right-handed women with regular menstrual cycles were tested twice, once during the menstrual phase, when progesterone and estradiol levels are low, and once during the luteal phase when progesterone and estradiol levels are high. Plasma steroid levels were determined by blood-based immunoassay at each session. It was found that IHTT, in particular from right-to-left, was generally longer during the luteal phase relative to the menstrual phase. This effect occurred as a consequence of a slowed absolute N170 latency of the indirect pathway (i.e. left hemispheric response after LVF stimulation) and, in particular, a shortened latency of the direct pathway (i.e. right hemispheric response after LVF stimulation) during the luteal phase. These results show that cycle-related effects are not restricted to modulation of processes between hemispheres but also apply to cortical interactions, especially within the right hemisphere. The findings support the view that plastic changes in the female brain occur during relatively short-term periods across the menstrual cycle. [Copyright &y& Elsevier]

Abstract: Several studies have shown that fluctuating levels of sex hormones (estrogen and progesterone) can affect fundamental principles of brain organization, including functional cerebral asymmetries (FCAs) and interhemispheric interactions. The majority of findings come from studies investigating younger women tested during distinct hormonal phases of the menstrual cycle, an approach that does not necessarily allow for conclusions about the causal relationship between hormonal changes and functional brain organization. An alternative approach is to manipulate the hormonal status of participants directly. This research focuses on the effects of hormone therapy (HT) on FCAs and interhemispheric interactions in postmenopausal women. Functional brain organization was tested in postmenopausal women using either estrogen therapy or combined estrogen plus gestagen therapy. The results are then compared to age- and IQ-matched postmenopausal women not taking HT. The results indicate HT-related modulations in both FCAs and interhemispheric interaction. In contrast to normally cycling women, however, it seems that HT, and especially estrogen therapy, after menopause affects intrahemispheric processing rather than interhemispheric crosstalk. The findings indicate a faster and more pronounced age-related decline in intrahemispheric relative to interhemispheric processing which seems to be accompanied by a higher sensitivity to HT. Aging processes together with differences in the hormonal status (exogenous changes as a result of HT vs. endogenous changes during the menstrual cycle) may also explain divergent (cognitive) behavioral outcomes in postmenopausal women and younger women. Taken together, the findings suggest that the female brain retains its plasticity even after reproductive age and remains susceptible to the effects of sex hormones throughout the lifetime. This article is part of a Special Issue entitled: Neuroactive Steroids: Focus on Human Brain. [Copyright &y& Elsevier]

Abstract: Objective: To determine if there are steroid-dependent changes in transcallosal transfer during the menstrual cycle in normal women. Methods: We tested 13 normally cycling women during the menstrual, follicular and midluteal phases. Blood levels of estradiol (E) and progesterone (P) were determined by radioimmunoassay. Ipsilateral tonic voluntary muscle activity suppression, called ipsilateral silent period (iSP), was evoked by applying transcranial magnetic stimulation (TMS) over the left motor cortex and by measuring the EMG of the ipsilateral first dorsal interosseus (FDI) muscle. Both iSP-duration and transcallosal conduction times were measured and related to cycle phase and steroid levels. Results: Duration of iSPs varied over the cycle with largest differences between follicular and midluteal phases. During the midluteal phase high levels of P were significantly related to short iSPs. This relation also applied to E levels and iSPs during the follicular phase. Conclusions: Our study shows for the first time that the transcallosal transfer is modulated by E and P and changes over the menstrual cycle. Significance: It is suggested that gonadal steroid hormones affect the interhemispheric interaction and change the functional cerebral organization sex dependently via its neuromodulatory properties on GABAergic and glutamatergic neurons. [Copyright &y& Elsevier]

Atoms of 82Rb (t1/2 = 76 s) confined in a time-orbiting-potential (TOP) magnetic trap make a favorable source for β-asymmetry studies by providing an essentially massless source of highly polarized atoms. An offline mass separator is coupled to a double magneto-optical trap (MOT) and TOP trap system. Once in the TOP trap the magnetic trap''s rotating bias field defines the polarization axis and allows one to measure the correlation between the nuclear spin direction and the β emission direction using a single positron detector. A proof-of-principle experiment using this method has demonstrated that the parity violating correlation can be studied. Here we outline improvements to the experiment with the goal of a 1% measurement of the β-asymmetry correlation parameter A in the Gamow-Teller decay of 82Rb which in the semi-leptonic sector would pose a competitive test of the Standard Model. [Copyright &y& Elsevier]

The Rare Isotope Accelerator (RIA) is designed to deliver unprecedented intensities and a wide variety of radioactive beams. There is interest in collecting many of the highest intensity, long-lived ( day) mass- and recoil-separated beams for the production of radioactive targets or for applications where high specific activity sources are needed. Based on an intensity of , collection rates of ∼ 2 μg/day or more are possible. Herein, we consider the primary or parasitic collection of mass-separated beams on either the ISOL mass separator or the recoil separator. Once the desired activity is collected, it may be used directly as a target or will be moved to a hot cell for radiochemical purification and target preparation. A concept for the collection and preparation of radioactive samples is outlined. [Copyright &y& Elsevier]

We present direct mass measurements of the short-lived 44V, 48Mn, 41Ti and 45Cr nuclei. A novel experimental method has been used that is based on projectile fragmentation, in-flight separation of relativistic heavy ions with the fragment separator (FRS), and on isochronous operation of the experimental storage ring (ESR). A mass resolving power of 110 000 (FWHM) and an accuracy of about (100–500) keV has been achieved. The impact of the present results on the rp-process in X-ray burst models is discussed. [Copyright &y& Elsevier]

We present results from two methods of direct mass measurements of relativistic exotic nuclei stored in the storage ring ESR. Schottky Mass Spectrometry (SMS) with electron-cooled ions is well suited for long-lived nuclei (T1/2⩾10 s), and the Isochronous mass measurements (IMS) for hot fragments (T1/2⩾1 μs). In addition, SMS provides information on nuclear lifetime for bare and highly ionized atoms. [Copyright &y& Elsevier]

Highlights: [•] Lateralized reaction times in a go/no-go task vary across the menstrual cycle. [•] Anterior cingulate cortex is less activated during go/no-go task in the luteal phase. [•] Functional organization of selective attention network is modulated by cycle phases. [ABSTRACT FROM AUTHOR]

A 410 MeV/u 238 U projectile beam was used to create cadmium isotopes via abrasion-fission in a beryllium target placed at the entrance of the in-flight separator FRS at GSI. The fission fragments were separated by the FRS and injected into the isochronous storage ring ESR for mass measurements. Isochronous Mass Spectrometry (IMS) was performed under two different experimental conditions, with and without B ρ -tagging at the high-resolution central focal plane of the FRS. In the experiment with B ρ -tagging the magnetic rigidity of the injected fragments was determined with an accuracy of 2 ⋅ 10 − 4 . A new method of data analysis, which uses a correlation matrix for the combined data set from both experiments, has provided experimental mass values of 25 rare isotopes for the first time. The high sensitivity and selectivity of the method have given access to nuclides detected with a rate of a few atoms per week. In this letter we present for the 129,130,131 Cd isotopes mass values directly measured for the first time. The experimental mass values of cadmium as well as for tellurium and tin isotopes show a pronounced shell effect towards and at N = 82 . Shell quenching cannot be deduced from a single new mass value, nor by a better agreement with a theoretical model which explicitly takes into account a quenching feature. This is in agreement with the conclusion from γ -ray spectroscopy and confirms modern shell-model calculations. [ABSTRACT FROM AUTHOR]

Abstract: First experimental evidence for a high-spin isomer () in 97Cd, a waiting point in the astrophysical rapid proton capture process, is presented. The data were obtained in β-decay studies at NSCL using the new RF Fragment Separator system and detecting β-delayed protons and β-delayed γ rays. Decays from ground and isomeric states were disentangled, and proton emission branches were determined for the first time. We find half-lives of 1.10(8) s and 3.8(2) s, and β-delayed proton emission branches of 12(2)% and 25(4)% were deduced for the ground and isomeric states, respectively. With these results, the nuclear data needed to determine an rp-process contribution to the unknown origin of solar 96Ru are in place. When the new data are included in astrophysical rp-process calculations, one finds that an rp-process origin of 96Ru is unlikely. [Copyright &y& Elsevier]

Abstract: The core-excited isomer in fully-ionized 133Sb has been directly studied for the first time by applying the novel technique of isochronous mass spectrometry at GSI. The neutron-rich nuclides in high charge states were produced by projectile fission of 411 MeV A 238U ions, separated in flight by the fragment separator (FRS) and stored in the isochronous storage ring (ESR). The measured excitation energy is 4.56(10) MeV. The neutral-atom half-life is known to be 17 μs. This is the shortest-lived isomer measured directly with mass spectrometry techniques. The extended in-flight half-life of the bare ions in the ESR, which is due to the exclusion of the strong internal conversion, demonstrates that there should be another nuclear level above that identified from isomer-decay spectroscopy, in support of shell-model calculations. This measurement opens up a new half-life domain for storage-ring measurements. [Copyright &y& Elsevier]

Abstract: The previously pioneered Isochronous Mass Spectrometry (IMS) has been extended by an additional precise magnetic-rigidity determination to enable accurate large-scale measurements of stored short-lived relativistic nuclei with the FRS-ESR facility at 382 MeV/u. With this novel experimental tool the mass resolving power and accuracy have been improved by a factor of about 3. The recorded broad-band revolution time spectrum corresponds to the mass-over-charge range of about 6%. A mass resolving power of 200 000 (FWHM) and a typical accuracy of 120 keV have been achieved almost over the entire spectrum. The masses of 35 neutron-rich nuclides have been directly measured in the element range from aluminum to barium. The Masses of 8 nuclides (85,86As, 89Se, 123Ag, 138Te, 140,141I, 143Xe) have been measured for the first time. The results are compared with previous experimental data and theoretical predictions. The evolution of the shell closure towards doubly-magic 78Ni is discussed. [Copyright &y& Elsevier]

Schottky Mass Spectrometry (SMS) and Isochronous Mass Spectrometry (IMS) have been successfully applied for direct mass measurements of exotic nuclides at FRS-ESR facility at GSI. Both experimental methods are sensitive to single stored ions and can cover very efficiently a large number of nuclides in one run. Presently, more than 1100 masses of different nuclides have been covered by SMS and IMS in several FRS-ESR experiments whereby about 350 of them have been determined for the first time. In this paper, we present the status of our experimental program and use the experimental mass values to test the predictive power of modern mass models. [Copyright &y& Elsevier]

Abstract: Masses of 582 neutron-deficient nuclides were measured with time-resolved Schottky mass spectrometry at the FRS-ESR facility at GSI, 117 were used for calibration. The masses of 71 nuclides were obtained for the first time. A typical mass accuracy of 30 μu was achieved. These data have entered the latest atomic mass evaluation. The mass determination of about 140 additional nuclides was possible via known energies (Q-values) of α-, β-, or proton decays. The obtained results are compared with the results of other measurements. [Copyright &y& Elsevier]

Recently, much progress has been made with stored exotic nuclei at relativistic velocities . Fragments of 208Pb and 209Bi projectiles and fission products from 238U ions were produced, separated in flight with the fragment separator FRS, and injected into the storage-cooler ring ESR for precision measurements. 114 new masses of neutron-deficient isotopes in the lead region have been measured with time-resolved Schottky Mass Spectrometry (SMS). A new isospin dependence of the pairing energy was observed due to the improved mass accuracy of typically 1.5×10-7 (30 keV). New masses of short-lived neutron-rich fission fragments have been obtained with Isochronous Mass Spectrometry (IMS). An innovative field of spectroscopy has been opened up with lifetime measurements of stored bare and few-electron fragments after applying both stochastic and electron cooling. [Copyright &y& Elsevier]

A large area on the mass surface of neutron-deficient nuclides (36≤Z≤85) was measured with time-resolved Schottky mass spectrometry at the FRS-ESR facilities. The masses of 114 nuclides were obtained for the first time from which 43 were determined via known decay energies. The improved mass accuracy of 30 keV allowed to study the isospin dependence of nuclear pairing, to precisely locate the one-proton dripline for odd-Z isotopes from Tb to Pa and to make crucial tests of the predictive powers of modern mass models. [Copyright &y& Elsevier]

The half-lives of isomeric states of fully ionized 144Tb, 149Dy and 151Er have been measured. These nuclides were produced via fragmentation of about 900 MeV/u 209Bi projectiles, separated in flight with the fragment separator (FRS) and stored in the cooler ring (ESR). The decay times of the cooled fragments have been measured with time-resolved Schottky spectrometry. We observed for the first time drastic increases of the half-lives of bare isomers by factors of up to 30 compared to their neutral counterparts. This is due to the exclusion of the strong internal conversion and electron-capture channels in the radioactive decay of these bare nuclei. The experimental results are in good agreement with theoretical calculations. [Copyright &y& Elsevier]