Disentangling unclear nuclear breakup channels of beryllium-9 using the three-axis Dalitz plot

The three-axis Dalitz plot has been applied to the breakup of a nucleus into unequal mass fragments for the first time. The Dalitz plot allows clear identification of the various breakup channels of 9Be → 2α + n process. The method has allowed the branching ratio for the 6.38 MeV level in9Be to be provisionally calculated when examining the 9Be(4He, α)ααn reaction. The effects of non-uniform angular distributions on the Dalitz plot must still be properly investigated along with the effects of contaminant reaction channels. It is proposed that this method could be used to determine the breakup branching ratio of a newly-measured level in this nucleus

Changing expression of vertebrate immunity genes in an anthropogenic environment: a controlled experiment

Background: The effect of anthropogenic environments on the function of the vertebrate immune system is a problem of general importance. For example, it relates to the increasing rates of immunologically-based disease in modern human populations and to the desirability of identifying optimal immune function in domesticated animals. Despite this importance, our present understanding is compromised by a deficit of experimental studies that make adequately matched comparisons between wild and captive vertebrates. Results: We transferred post-larval fishes (three-spined sticklebacks), collected in the wild, to an anthropogenic (captive) environment. We then monitored, over 11 months, how the systemic expression of immunity genes changed in comparison to cohort-matched wild individuals in the originator population (total n = 299). We found that a range of innate (lyz, defbl2, il1r-like, tbk1)and adaptive (cd8a, igmh) immunity genes were up-regulated in captivity, accompanied by an increase in expression of the antioxidant enzyme, gpx4a. For some genes previously known to show seasonality in the wild, this appeared to be reduced in captive fishes. Captive fishes tended to express immunity genes, including igzh, foxp3b, lyz, defbl2, and il1r-like, more variably. Furthermore, although gene co-expression patterns (analyzed through gene-by-gene correlations and mutual information theory based networks) shared common structure in wild and captive fishes, there was also significant divergence. For one gene in particular, defbl2, high expression was associated with adverse health outcomes in captive fishes. Conclusion: Taken together, these results demonstrate widespread regulatory changes in the immune system in captive populations, and that the expression of immunity genes is more constrained in the wild. An increase in constitutive systemic immune activity, such as we observed here, may alter the risk of immunopathology and contribute to variance in health in vertebrate populations exposed to anthropogenic environments

Economic analysis of empiric versus diagnostic-driven strategies for immunocompromised patients with suspected fungal infections in the People's Republic of China

Ningying Mao,1 Beth Lesher,2 Qifa Liu,3 Lei Qin,2 Yixi Chen,4 Xin Gao,2 Stephanie R Earnshaw,5 Cheryl L McDade,5 Claudie Charbonneau,61School of International Pharmaceutical Business, China Pharmaceutical University, Nanjing, People's Republic of China; 2Pharmerit International, Bethesda, MD, USA; 3Hematology Department, Nanfang Hospital, Southern Medical University, Guangzhou, 4Pfizer Investment Co. Ltd., Beijing, People's Republic of China; 5RTI Health Solutions, Research Triangle Park, NC, USA; 6Pfizer International Operations, Paris, France Abstract: Invasive fungal infections (IFIs) require rapid diagnosis and treatment. A decision-analytic model was used to estimate total costs and survival associated with a diagnostic-driven (DD) or an empiric treatment approach in neutropenic patients with hematological malignancies receiving chemotherapy or autologous/allogeneic stem cell transplants in Shanghai, Beijing, Chengdu, and Guangzhou, the People's Republic of China. Treatment initiation for the empiric approach occurred after clinical suspicion of an IFI; treatment initiation for the DD approach occurred after clinical suspicion and a positive IFI diagnostic test result. Model inputs were obtained from the literature; treatment patterns and resource use were based on clinical opinion. Total costs were lower for the DD versus the empiric approach in Shanghai (¥3,232 vs ¥4,331), Beijing (¥3,894 vs ¥4,864), Chengdu, (¥4,632 vs ¥5,795), and Guangzhou (¥8,489 vs ¥9,795). Antifungal administration was lower using the DD (5.7%) than empiric (9.8%) approach, with similar survival rates. Results from one-way and probabilistic sensitivity analyses were most sensitive to changes in diagnostic test sensitivity and IFI incidence; the DD approach dominated the empiric approach in 88% of scenarios. These results suggest that a DD compared to an empiric treatment approach in the People’s Republic of China may be cost saving, with similar overall survival in immunocompromised patients with suspected IFIs. Keywords: aspergillosis, cost-effectiveness analysis, voriconazole, caspofungin, itraconazol

β − decay of 65 Mn to65 Fe

The low-energy structure of 65Fe has been studied by means ofγand fast-timing spectroscopy at the ISOLDE facility, CERN. A level scheme of 65Fe populated following the β− decay of 65Mn was established for the first time. It includes 41 levels and 85 transitions. The excitation energy of the β-decaying isomer in 65Fe has been precisely determined at 393.7(2) keV. Theβ-delayed neutron emission branch was measured asPn=7.9(12)%, which cannot be reconciled with the previously reported value of 21.0(5)%. Fourγrays and four excited states in 64Fe were identified as being populated following theβ-ndecay. Four lifetimes and five lifetime limits in the subnanosecond range have been measured using the advanced time-delayedβγγ(t) method. The level scheme is compared with shell-model calculations. Tentative spin and parity assignments are proposed based on the observed transition rates, the calculations, and the systematics of the region.status: publishe

Search for shape-coexisting 0+ states in 66Ni from lifetime measurements

The lifetime of the 0+3 state in 66Ni, two neutrons below the N=40 subshell gap, has been measured. The transition B(E2;0+3→2+1) is one of the most hindered E2 transitions in the Ni isotopic chain and it implies that, unlike 68Ni, there is a spherical structure at low excitation energy. We have performed extensive shell-model calculations that correctly predict this result, obtaining a spherical 0+ state at the correct energy and with an extremely low B(E2;0+3→2+1) value.status: publishe

Particle- γ coincidence spectroscopy of the N = 90 nucleus 154Gd by (p, tγ)

A segmented Si-telescope and HPGe array, STARS-LIBERACE, was used to study the 156Gd(p, tγ)154Gd direct reaction by particle- γ coincidence spectroscopy. New cross sections with a 25MeV proton beam are reported and compared to previous (p,t) and (t,p) studies. Furthermore, additional evidence for coexisting Kπ=01+,21+ and 02+, 22+ configurations at N = 90 is presented. Direct and indirect population patterns of the low-lying states are also explored. Review of the new and existing evidence favors an interpretation based on a configuration-dependent pairing interaction. The weakening of monopole pairing strength and an increase in quadrupole pairing strength could bring 2p-2h 0 + states below 2 Δ. This may account for a large number of the low-lying 0 + states observed in two-nucleon transfer reactions. A hypothesis for the origin of the 02+ and 03+ states is provided

Properties of low-lying states in 65Co from lifetime measurements

© 2019 American Physical Society. The low-energy structure of Co65 was studied by means of γ-and fast-timing spectroscopy at the ISOLDE/CERN facility. The known level scheme of Co65 populated following the β-decay of Fe65 was expanded. The experimental results were compared with large-scale shell-model calculations. The measured long lifetime of the (1/21-) level confirms its nature as a highly collective state with proton excitations across the Z=28 gap and neutrons across the N=40 subshell.status: publishe

Signatures of the Z=82 Shell Closure in α-Decay Process

In recent experiments at the velocity filter Separator for Heavy Ion reaction Products (SHIP) (GSI, Darmstadt), an extended and improved set of α-decay data for more than 20 of the most neutron-deficient isotopes in the region from lead to thorium was obtained. The combined analysis of this newly available α-decay data, of which the 186Po decay is reported here, allowed us for the first time to clearly show that crossing the Z=82 shell to higher proton numbers strongly accelerates the α-decay. From the experimental data, the α-particle formation probabilities are deduced following the Universal Decay Law approach. The formation probabilities are discussed in the framework of the pairing force acting among the protons and the neutrons forming the α particle. A striking resemblance between the phenomenological pairing gap deduced from experimental binding energies and the formation proba- bilities is noted. These findings support the conjecture that both the N=126 and Z=82 shell closures strongly influence the α-formation probability.status: publishe

New results on fission cross sections in actinide nuclei using the surrogate ratio method and on conversion coefficients in triaxial strongly deformed bands in167Lu from ice ball and gammasphere

The surrogate ratio technique is described. New results for neutron induced fission cross sections on actinide nuclei, obtained using this technique are presented. The results benchmark the surrogate ratio technique and indicate that the method is accurate to within 5% over a wide energy range. New results for internal conversion coefficients in triaxial strongly deformed bands in 167Lu are also presented