Study of Quasielastic Barrier Distributions as a Step towards the Synthesis of Superheavy Elements with Hot Fusion Reactions.

The excitation functions for quasielastic scattering of ^{22}Ne+^{248}Cm, ^{26}Mg+^{248}Cm, and ^{48}Ca+^{238}U are measured using a gas-filled recoil ion separator. The quasielastic barrier distributions are extracted for these systems and are compared with coupled-channel calculations. The results indicate that the barrier distribution is affected dominantly by deformation of the actinide target nuclei, but also by vibrational or rotational excitations of the projectile nuclei, as well as neutron transfer processes before capture. From a comparison between the experimental barrier distributions and the evaporation residue cross sections for Sg (Z=106), Hs (108), Cn (112), and Lv (116), it is suggested that the hot fusion reactions take advantage of a compact collision, where the projectile approaches along the short axis of a prolately deformed nucleus. A new method is proposed to estimate the optimum incident energy to synthesize unknown superheavy nuclei using the barrier distribution.

Cloud Quantum Computing of an Atomic Nucleus.

We report a quantum simulation of the deuteron binding energy on quantum processors accessed via cloud servers. We use a Hamiltonian from pionless effective field theory at leading order. We design a low-depth version of the unitary coupled-cluster ansatz, use the variational quantum eigensolver algorithm, and compute the binding energy to within a few percent. Our work is the first step towards scalable nuclear structure computations on a quantum processor via the cloud, and it sheds light on how to map scientific computing applications onto nascent quantum devices.

Coupled-cluster computations of atomic nuclei.

In the past decade, coupled-cluster theory has seen a renaissance in nuclear physics, with computations of neutron-rich and medium-mass nuclei. The method is efficient for nuclei with product-state references, and it describes many aspects of weakly bound and unbound nuclei. This report reviews the technical and conceptual developments of this method in nuclear physics, and the results of coupled-cluster calculations for nucleonic matter, and for exotic isotopes of helium, oxygen, calcium, and some of their neighbors.

Dermatoglyphic asymmetries and fronto-striatal dysfunction in young adults reporting non-clinical psychosis.

OBJECTIVE: Growing evidence indicates that non-clinical psychotic-like experiences occur in otherwise healthy individuals, suggesting that psychosis may occur on a continuum. However, little is known about how the diathesis for formal psychosis maps on to individuals at the non-clinical side of this continuum. Our current understanding of the pathophysiology of schizophrenia implicates certain key factors such as early developmental abnormalities and fronto-striatal dysfunction. To date, no studies have examined these core factors in the context of non-clinical psychosis. METHOD: A total of 221 young adults were assessed for distressing attenuated positive symptoms (DAPS), dermatoglyphic asymmetries (a marker of early developmental insult), and procedural memory (a proxy for fronto-striatal function). RESULTS: Participants reporting DAPS (n = 16; 7.2%) and no-DAPS (n = 205; 92.7%) were split into two groups. The DAPS group showed significantly elevated depression, elevated dermatoglyphic asymmetries, and a pattern of procedural learning consistent with other studies with formally psychotic patients. CONCLUSION: The results indicate that the non-clinical side of the psychosis continuum also shares key vulnerability factors implicated in schizophrenia, suggesting that both early developmental disruption and abnormalities in fronto-striatal function are core aspects underlying the disorder.

Origin of the anomalous long lifetime of ¹4C.

We report the microscopic origins of the anomalously suppressed beta decay of ¹4C to ¹4N using the ab initio no-core shell model with the Hamiltonian from the chiral effective field theory including three-nucleon force terms. The three-nucleon force induces unexpectedly large cancellations within the p shell between contributions to beta decay, which reduce the traditionally large contributions from the nucleon-nucleon interactions by an order of magnitude, leading to the long lifetime of ¹4C.

Pairing reentrance phenomenon in heated rotating nuclei in the shell-model Monte Carlo approach.

Rotational motion of heated 72Ge is studied within the microscopic shell-model Monte Carlo approach. We investigate the angular momentum alignment and nuclear pairing correlations associated with J^{π} Cooper pairs as a function of the rotational frequency and temperature. The reentrance of pairing correlations with temperature is predicted at high rotational frequencies. It manifests itself through the anomalous behavior of specific heat and level density.

Observation of coherent elastic neutrino-nucleus scattering.

The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross section is by far the largest of all low-energy neutrino couplings. This mode of interaction offers new opportunities to study neutrino properties and leads to a miniaturization of detector size, with potential technological applications. We observed this process at a 6.7σ confidence level, using a low-background, 14.6-kilogram CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source at Oak Ridge National Laboratory. Characteristic signatures in energy and time, predicted by the standard model for this process, were observed in high signal-to-background conditions. Improved constraints on nonstandard neutrino interactions with quarks are derived from this initial data set.

De novo synthesis and secretion of heterogeneous forms of human chorionic gonadotropin and its free alpha-subunit in the human choriocarcinoma clonal cell line JEG-3.

The clonal human choriocarcinoma cell line JEG-3 secretes hCG and heterogeneous forms of its free alpha-subunit. We have studied the relationship of these forms in de novo biosynthesis experiments. Cells at near confluence were labeled with [35S]methionine by continuous (10-min to 24-h exposure) and by pulse-chase (5-min exposure, 10-min to 4-h chase) techniques. Media and cell lysates, chromatographed in Sephadex G-100 or, after reduction, electrophoresed on 12-20% gradient sodium dodecyl sulfate-polyacrylamide slab gels (SDS-PAG:), were analyzed by immunoprecipitation with antisera to hCT-alpha and hCG-beta. The intracellular labeled free alpha-subunit observed in lysates at all time points of either continuous or pulse-chase experiments was the same size or was slightly smaller on G-100 (apparent mol wt, 21,600 +/- 3,900) than urinary standard alpha-subunit (CR119 alpha; apparent mol wt, 22,700 +/- 1,500) and also somewhat smaller on SDS-PAGE (apparent mol wt, 19,400 +/- 600) than urinary standard alpha-subunit (apparent mol wt, 20,200 +/- 1,100). However, the predominant form of secreted free alpha-subunit, at chase times as early as 30 min, migrated with a higher apparent molecular weight in both systems (SDS-PAGE, 22,100 +/- 400; G-100, 29,300 +/- 2,700). We have not observed this secreted large free alpha-subunit in the cell lysate, and our data suggest that the small intracellular alpha-subunit is a precursor of the larger secreted alpha-subunit and not vice versa. The beta-subunit of secreted hCG was somewhat larger (apparent mol wt, 31,500 +/- 1,000) on SDS-PAGE than standard beta-subunit (CR119-2 beta and CR115 beta; apparent mol wt, 29,900 +/- 1,900). Secreted intact hCG migrated with urinary standard hCG (CR119) on G-100, but analysis of 35S-labeled intracellular hCG was complicated by co-precipitating large mol wt proteins. De novo synthesis and secretion of a large form of free alpha-subunit as well as a large beta-subunit in hCG may be due to posttranslational oligosaccharide addition during the secretory process.

Brief dietary restriction increases skeletal muscle glucose transport in old Fischer 344 rats.

The primary purpose of this study was to determine the impact of brief dietary restriction (DR; 5 or 20 days) on skeletal muscle glucose transport activity (GTA) of 24-month-old female Fischer 344 rats. Basal GTA of isolated epitrochlearis muscles was unaffected by DR. Insulin-stimulated GTA was significantly increased by DR only at 20 days (51%). We also assessed the influence of DR on energy sources (blood-borne and stored). An approximately 20% decline in glycemia occurred in each DR group, but plasma-free fatty acid and beta-hydroxybutyrate concentrations were unaffected. Plasma insulin was reduced by 50% after 20 days. Hepatic glycogen was rapidly mobilized (-69% at 5 days; -83% at 20 days). The depletions of visceral adipose stores was slower (no significant decline at 5 days; -30% at 20 days), but the eventual reduction accounts for a significant amount of energy. The results demonstrate that muscle from old rats can rapidly upregulate GTA in response to brief DR. The relative magnitude of this increase represents a substantial portion of the increases previously observed after prolonged DR.

Solution of the center-of-mass problem in nuclear structure calculations.

The coupled-cluster wave function factorizes to a very good approximation into a product of an intrinsic wave function and a Gaussian for the center-of-mass coordinate. The width of the Gaussian is in general not identical to the oscillator length of the underlying single-particle basis. The quality of the separation can be verified by a simple procedure.

Medium-mass nuclei from chiral nucleon-nucleon interactions.

We compute the binding energies, radii, and densities for selected medium-mass nuclei within coupled-cluster theory and employ a bare chiral nucleon-nucleon interaction at next-to-next-to-next-to-leading order. We find rather well-converged results in model spaces consisting of 15 oscillator shells, and the doubly magic nuclei 40Ca, 48Ca, and the exotic 48Ni are underbound by about 1 MeV per nucleon within the coupled-cluster singles-doubles approximation. The binding-energy difference between the mirror nuclei 48Ca and 48Ni is close to theoretical mass table evaluations. Our computation of the one-body density matrices and the corresponding natural orbitals and occupation numbers provides a first step to a microscopic foundation of the nuclear shell model.

Ab-initio coupled-cluster study of 16O.

We report converged results for the ground and excited states and matter density of 16O using realistic two-body nucleon-nucleon interactions and coupled-cluster methods and algorithms developed in quantum chemistry. Most of the binding is obtained with the coupled-cluster singles and doubles approach. Additional binding due to three-body clusters (triples) is minimal. The coupled-cluster method with singles and doubles provides a good description of the matter density, charge radius, charge form factor, and excited states of a one-particle, one-hole nature, but it cannot describe the first-excited 0(+) state. Incorporation of triples has no effect on the latter finding.

Quadrupole deformation of the self-conjugate nucleus 72Kr.

We report on the first determination of the absolute B(E2;0+(1)-->2+(1)) excitation strength in the N=Z nucleus 72Kr. 72Kr is the heaviest N=Z nucleus for which this quantity has been measured and provides a benchmark in a region of the nuclear chart dominated by rapidly changing deformations and shapes mediated by the interplay of strongly oblate and prolate-driving orbitals. The deduced quadrupole deformation strength is in agreement with a variety of self-consistent models that predict an oblate shape for the ground state of 72Kr. Large-scale shell-model Monte Carlo calculations reproduce the experimental B(E2) value and link the result to the occupation of the deformation-driving g9/2 orbit.

The development of professional and political awareness in nursing.

The fiduciary relationship between the client and the professional who has been hired to provide a service rarely exists today between nurses and patients, Nurses are employed by the State and operate in organizations where elements of both the bureaucratic and professional models are integrated. This paper discusses nursing's adaptation to the ever-changing health system in the United Kingdom and how this has resulted in the involvement of senior nurses in the political process. The mechanisms which result in policy output are discussed with reference to the power of nurses. It is argued that all nurses have a role in the decision-making process through the use of influence which will result from the development of political awareness.

Glucose transport with brief dietary restriction: heterogenous responses in muscles.

The time course (1, 5, or 20 days) for the effect of dietary restriction (DR; approximately 25% reduction below ad libitum intake) on epitrochlearis and flexor digitorum brevis (FDB) muscle glucose transport activity was studied in female Fischer 344 rats (8 mo old). Epitrochlearis glucose transport activity with 100 microU/ml insulin was increased by 38% after 5 days of DR (P < 0.05) despite no change in glucose transport activity with 0 or 20,000 microU/ml insulin. The increase with 100 microU/ml insulin was not further enhanced by 20 days of DR. DR did not result in a significant increase in the glucose transport activity of the FDB with 0, 100, or 20,000 microU/ml insulin. Abdominal fat content was significantly (P < 0.01) reduced below ad libitum levels only after 20 days of DR. These results demonstrate that DR-induced improvement in epitrochlearis glucose transport activity with a physiological insulin concentration can occur very rapidly, preceding detectable changes in basal or maximal insulin-stimulated glucose transport activity or abdominal fat pad mass, and the enhancement of insulin action does not occur simultaneously in all muscles.

Calorie restriction increases insulin-stimulated tyrosine phosphorylation of insulin receptor and insulin receptor substrate-1 in rat skeletal muscle.

A moderate reduction in calorie intake (calorie restriction, CR) improves insulin-stimulated glucose transport in skeletal muscle. Therefore, we studied muscle insulin signalling in ad libitum (AL) and CR ( approximately 60% AL intake for 20 days) fed rats, which received a control injection (sterile water) or an insulin injection (30 U kg-1 body weight). In control (not insulin-treated) rats, there was no detectable tyrosine phosphorylation of insulin receptor (IR), regardless of diet; no diet effect on tyrosine phosphorylation of insulin receptor substrate-1 (IRS1) or IRS1-associated phosphatidylinositol 3-kinase (PI3K) protein and 21% higher IRS1-associated PI3K activity in AL vs. CR. In insulin-treated rats, tyrosine-phosphorylated IR was 79% higher for CR vs. AL; tyrosine-phosphorylated IRS1 was 109% higher for CR vs. AL; IRS1-associated PI3K protein and IRS1-associated PI3K activity were unaffected by diet. Calorie restriction amplifies early insulin signalling steps without changing IRS1-associated PI3K, suggesting enhanced glucose transport is mediated by altering: IRS1-PI3K localization, PI3K associated with proteins other than IRS1 or post-PI3K events.