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Some pests may be present on plants for planting and cause an unacceptable economic impact on the intended use of these plants, even though they are already present in the area. By consequence, these pests may be regulated and then called ‘Regulated Non-Quarantine Pests’ (RNQPs) according to international standards. RNQPs, often not identified as such, are commonly regulated either together with quarantine pests in plant health regulations, or within programmes for the certification of plants for planting through specific requirements for pests and diseases that come in addition to non-phytosanitary requirements. In 2016, Union RNQPs have been introduced in the new EU plant health regulation which shall apply from December 2019. In this context, EPPO agreed to undertake a 2-year project on RNQPs, the EU Quality Pest Project. After having developed a methodology, data were collected through a rapid bibliography of scientific literature, questionnaire responses, exchanges on practical experience within six sector expert working groups, as well as a consultation of EPPO member countries, in order to perform a rapid evaluation of the RNQP status of about 1400 pest-host-intended use combinations. The resulting list of pests fulfilling the RNQP definition is presented in this paper, as well as the main issues discussed on thresholds and risk management measures.
The 12Cðα; γÞ16O reaction plays a central role in astrophysics, but its cross section at energies relevant for astrophysical applications is only poorly constrained by laboratory data. The reduced α width, γ11, of the bound 1− level in 16O is particularly important to determine the cross section. The magnitude of γ11 is determined via sub-Coulomb α-transfer reactions or the β-delayed α decay of 16N, but the latter approach is presently hampered by the lack of sufficiently precise data on the β-decay branching ratios. Here we report improved branching ratios for the bound 1− level [bβ;11 ¼ ð5.02 0.10Þ × 10−2] and for β-delayed α emission [bβα ¼ ð1.59 0.06Þ × 10−5]. Our value for bβα is 33% larger than previously held, leading to a substantial increase in γ11. Our revised value for γ11 is in good agreement with the value obtained in α-transfer studies and the weighted average of the two gives a robust and precise determination of γ11, which provides significantly improved constraints on the 12Cðα; γÞ cross section in the energy range relevant to hydrostatic He burning.
The β decays from both the ground state and a long-lived isomer of 133In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to β, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant β-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their β decays selectively populate only a few isolated neutron unbound states in 133Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark β-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the β decay of neutron-rich nuclei southeast of 132Sn and will serve as a guide for future theoretical development aiming to describe accurately the key β decays in the rapid-neutron capture (r-) process.
A Coulomb excitation campaign on 106,108,110Sn at 4.4–4.5 MeV/u was launched at the HIE-ISOLDE facility at CERN. Larger excitation cross sections and γ-ray statistics were achieved compared to previous experiments at ∼2.8 MeV/u. More precise B(E2;0+1→2+1) values, lifetimes of states via the Doppler shift attenuation method, and new B(E2;0+1→2+x), B(E2;2+1→4+1), and Q(2+1) values from the new Miniball data will be obtained and applied to test modern nuclear structure theories.