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A direct measurement of the decay width of the excited $0^+_1$ state of $^6$Li using the relative self-absorption technique is reported. Our value of $\Gamma_{\gamma, 0^+_1 \to 1^+_1} = 8.17(14)_\mathrm{stat.}(11)_\mathrm{syst.} \mathrm{eV}$ provides sufficiently low experimental uncertainties to test modern theories of nuclear forces. The corresponding transition rate is compared to the results of ab initio calculations based on chiral effective field theory that take into account contributions to the magnetic dipole operator beyond leading order. This enables a precision test of the impact of two-body currents that enter at next-to-leading order., Comment: 7 pages, 3 figures

Preventing harm remains a persistent challenge in the ICU despite evidence-based practices known to reduce the prevalence of adverse events. This review seeks to describe the critical role of safety culture and patient and family engagement in successful quality improvement initiatives in the ICU. We review the evidence supporting the impact of safety culture and provide practical guidance for those wishing to implement initiatives aimed at improving safety culture and more effectively integrate patients and families in such efforts.Literature review using PubMed including evaluation of key studies assessing large-scale quality improvement efforts in the ICU, impact of safety culture on patient outcomes, methodologies for quality improvement commonly used in healthcare, and patient and family engagement. Print and web-based resources from leading patient safety organizations were also searched.Our group completed a review of original studies, review articles, book chapters, and recommendations from leading patient safety organizations.Our group determined by consensus which resources would best inform this review.A strong safety culture is associated with reduced adverse events, lower mortality rates, and lower costs. Quality improvement efforts have been shown to be more effective and sustainable when paired with a strong safety culture. Different methodologies exist for quality improvement in the ICU; a thoughtful approach to implementation that engages frontline providers and administrative leadership is essential for success. Efforts to substantively include patients and families in the processes of quality improvement work in the ICU should be expanded.Efforts to establish a culture of safety and meaningfully engage patients and families should form the foundation for all safety interventions in the ICU. This review describes an approach that integrates components of several proven quality improvement methodologies to enhance safety culture in the ICU and highlights opportunities to include patients and families.

The E2/M1 multipole mixing ratio δ_{1→2} of the 1_{sc}^{+}→2_{1}^{+} γ-ray decay in ^{156}Gd and hence the isovector E2 transition rate of the scissors mode of a well-deformed rotational nucleus has been measured for the first time. It has been obtained from the angular distribution of an artificial quasimonochromatic linearly polarized γ-ray beam of energy 3.07(6) MeV scattered inelastically off an isotopically highly enriched ^{156}Gd target. The data yield first direct support for the deformation dependence of effective proton and neutron quadrupole boson charges in the framework of algebraic nuclear models. First evidence for a low-lying J^{π}=2^{+} member of the rotational band of states on top of the 1^{+} band head is obtained, too, indicating a significant signature splitting in the K=1 scissors mode rotational band.

R. Reifarth et al: ; 12 págs.; 9 figs.; Open Access funded by Creative Commons Atribution Licence 3.0 ; Nuclear Physics in Astrophysics VI (NPA6), The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process ow and r-process -decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will oer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes., This project was supported by the HGF Young Investigators Project VH-NG-327, EMMI, H4F, HGS-HIRe, JINA, NAVI, DFG and ATHENA.

The Darmstadt High-Intensity Photon Setup (DHIPS) for photon-scattering and photodissociation experiments at the superconducting electron linear accelerator S–DALINAC has been improved. We report on its present performance. The developments include the installation of a segmented radiator for an online evaluation of the beam energy and the construction of a second photon-scattering setup with a Clover detector to deduce parity assignments. The enhancement of the existing photon-scattering setup with an additional 100% HPGe detector and some minor changes are described as well as the installation of two setups for photon-induced activation. In addition, we present a comparison of experimental data to Monte Carlo simulations using the codes Geant 3.21 and GEANT4.

The (J,T)=(1,1) parity doublet in 20Ne at 11.26 MeV is a good candidate to study parity violation in nuclei. However, its energy splitting is known with insufficient accuracy for quantitative estimates of parity violating effects. To improve on this unsatisfactory situation, nuclear resonance fluorescence experiments using linearly and circularly polarized γ-ray beams were used to determine the energy difference of the parity doublet ΔE=E(1−)−E(1+)=−3.2(±0.7)stat(−1.2+0.6)sys keV and the ratio of their integrated cross sections Is,0(+)/Is,0(−)=29(±3)stat(−7+14)sys. Shell-model calculations predict a parity-violating matrix element having a value in the range 0.46–0.83 eV for the parity doublet. The small energy difference of the parity doublet makes 20Ne an excellent candidate to study parity violation in nuclear excitations. Keywords: Parity doublet, Parity violation

Trying to remember something now typically improves your ability to remember it later. However, after watching a video of a simulated bank robbery, participants who verbally described the robber were 25% worse at identifying the robber in a lineup than were participants who instead listed U.S. states and capitals—this has been termed the “verbal overshadowing” effect (Schooler & Engstler-Schooler, 1990). More recent studies suggested that this effect might be substantially smaller than first reported. Given uncertainty about the effect size, the influence of this finding in the memory literature, and its practical importance for police procedures, we conducted two collections of preregistered direct replications (RRR1 and RRR2) that differed only in the order of the description task and a filler task. In RRR1, when the description task immediately followed the robbery, participants who provided a description were 4% less likely to select the robber than were those in the control condition. In RRR2, when the description was delayed by 20 min, they were 16% less likely to select the robber. These findings reveal a robust verbal overshadowing effect that is strongly influenced by the relative timing of the tasks. The discussion considers further implications of these replications for our understanding of verbal overshadowing.

The low-lying dipole strength of the open-shell nucleus ${}^{94}$Mo was studied via the nuclear resonance fluorescence technique up to 8.7 MeV excitation energy at the bremsstrahlung facility at the Superconducting Darmstadt Electron Linear Accelerator (S-DALINAC), and with Compton backscattered photons at the High Intensity $\ensuremath{\gamma}$-ray Source (HI$\ensuremath{\gamma}$S) facility. In total, 83 excited states were identified. Exploiting polarized quasi-monoenergetic photons at HI$\ensuremath{\gamma}$S, parity quantum numbers were assigned to 41 states excited by dipole transitions. The electric dipole-strength distribution was determined up to 8.7 MeV and compared to microscopic calculations within the quasiparticle phonon model. Calculations and experimental data are in good agreement for the fragmentation, as well as for the integrated strength. The average decay pattern of the excited states was investigated exploiting the HI$\ensuremath{\gamma}$S measurements at five energy settings. Mean branching ratios to the ground state and first excited ${2}_{1}^{+}$ state were extracted from the measurements with quasi-monoenergetic photons and compared to $\ensuremath{\gamma}$-cascade simulations within the statistical model. The experimentally deduced mean branching ratios exhibit a resonance-like maximum at 6.4 MeV which cannot be reproduced within the statistical model. This indicates a nonstatistical structure in the energy range between 5.5 and 7.5 MeV.

The nucleus $^{154}\mathrm{Gd}$ is located in a region of the nuclear chart where rapid changes of nuclear deformation occur as a function of particle number. It was investigated using a combination of $\ensuremath{\gamma}$-ray scattering experiments and a $\ensuremath{\gamma}\ensuremath{\gamma}$-coincidence study following electron capture decay of $^{154}\mathrm{Tb}^{m}$. A novel decay channel from the scissors mode to the first excited ${0}^{+}$ state was observed. Its transition strength was determined to $B(M1;{1}_{sc}^{+}\ensuremath{\rightarrow}{0}_{2}^{+})=0.031(4){\ensuremath{\mu}}_{N}^{2}$. The properties of the scissors mode of $^{154}\mathrm{Gd}$ imply a much larger matrix element than previously thought for the neutrinoless double-$\ensuremath{\beta}$ decay to the ${0}_{2}^{+}$ state in such a shape-transitional region. Theory indicates an even larger effect for $^{150}\mathrm{Nd}$.

The nucleus (154)Gd is located in a region of the nuclear chart where rapid changes of nuclear deformation occur as a function of particle number. It was investigated using a combination of γ-ray scattering experiments and a γγ-coincidence study following electron capture decay of (154)Tb(m). A novel decay channel from the scissors mode to the first excited 0(+) state was observed. Its transition strength was determined to B(M1;1(sc)(+)→0(2)(+))=0.031(4)μ(N)(2). The properties of the scissors mode of (154)Gd imply a much larger matrix element than previously thought for the neutrinoless double-β decay to the 0(2)(+) state in such a shape-transitional region. Theory indicates an even larger effect for (150)Nd.

This paper will discuss current work associated with the investigation of equipment damage induced by the application of fire suppressants. This discussion will be presented through an examination of several nuclear power plant incidents in which the spurious actuation of one or more fire suppression systems has occurred. The effects of these actuations on plant equipment, systems, and operation will be described. Also presented are the results of scoping calculations of the risk significance of spurious suppression system actuation. Finally, the paper will provide a description of efforts recommended to further investigate the impact of such incidents on plant operations and plant risk.

The Chinese citrus fruit fly, Bactrocera (Tetradacus) minax (Enderlein), is one of the major citrus pests in Bhutan and can cause50% mandarin (Citrus reticulata Blanco) fruit drop. As part of the development of a management strategy for the fly in mandarin orchards, population monitoring and experimental manipulations were carried out to determine: (i) adult emergence period; (ii) adult phenology patterns; (iii) period of crop susceptibility; and (iv) period from fruit drop to pupation. In western Bhutan, adult flies emerge from the overwintering pupal stage in late April/early May. Most flies are mature by the end of May and it is inferred that mating occurs at this time: from the beginning of June males rapidly disappear from the population and by mid- to late June are rare or absent from traps. Mature females are present in the mandarin crop at the beginning of June, but very little oviposition occurs until mid-June, while most damage has occurred by mid-July. Initiation of oviposition into mandarins is almost certainly linked to crop phenology. Adult flies disappear from the orchard system during August. After fruit drop, larvae were recorded leaving the fruit to pupate within 13 days. The use of early to mid-season protein bait sprays and/or targeted use of systemic insecticides during the one month oviposition period, plus the removal of fallen fruit once every 10 days, are recommended as control strategies.

In Book One of Clausewitz's "On War", he writes, "In war the result is never final. The defeated state often considers the outcome merely as a transitory evil, for which a remedy may be found in political conditions at some later date. The state of relations between the United States and North Korea, also known as the Democratic Peoples Republic of Korea (DPRK), embodies this truism today. An armistice agreement in 1953 provided for a cease-fire between North Korea and the United States, but the peace treaty to end the war has yet to be negotiated, leaving a large armed camp on either side of the 38th parallel warily eyeing each other for the past 49 years. Since the signing of the Armistice, the Republic of Korea (ROK or South Korea) has flourished into a stable democratic country with a healthy and powerful economy. At the same time, the DPRK, under a communist totalitarian regime, has grown evermore isolated and teeters on the edge of collapse. However, the DPRK's military, coupled with its development and export of missile technology and pursuit of a nuclear weapons capability, threatens the stability of the entire region. The United States has declared this region an area of national interest and, therefore, must counter North Korea's actions to provide for stability in the region. This paper will examine the nature of the relationship between the United States and the countries of the region to identify national objectives and formulate a national security and military strategy to achieve them.

Use of ethylenediamine (en) and the tripod ligand 1,3-diamino-2-(aminomethyl)propane (daap) results in cobalt(III)-pentamine complexes with obligate configuration. Optimization of the synthesis of [(en)(daap)Co] 2 O 2 4+ suggests that daap must undergo conformational change for complete coordination. Ultraviolet and visible spectra of [(en)(daap)Co] 2 O 2 4+ , [(en)(daap)Co] 2 O 2 5+ , [Co(daap)(enOH] 2+ , and Co-(daap)(en)H 2 O] 3+ are consistent with those of similar complexes. NMR spectra for [(en)(daap)Co] 2 O 2 4+ and for paramagnetic [(en)(daap)Co] 2 O 2 5+ were observed and assigned. The aqueous acidity of the cation [Co(daap)(en)H 2 O] 3+ was obtained at various ionic strengths.

It has often been believed that inH∞-optimal synthesis methods, the resulting controllers have order much greater than the order of the plant. Recently, Limebeer and Hung [9] have shown that inH∞-optimal synthesis problems of the “first kind” both optimal as well as suboptimal controllers have order which is no greater than the order of the plant. However, those authors do not provide any explicit algorithm for computing these controllers. In this paper we derive an explicit procedure for computing suboptimal controllers in problems of the first kind. These controllers have order no greater than the order of the plant and can be computed by solving only two Riccati and two Lyapunov equations.

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Excerpt Probably one of the greatest advances in internal medicine during the last half century has been the increasingly more common recognition of the fact that the important consideration in eva...