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The main use of black soldier fly larvae (Hermetia illucens) is currently as an animal feed ingredient. While the bacterial community of the larvae has been characterised repeatedly via sequencing, microbiological safety assessment based on culture-dependent techniques is still scarce. This study focused on the occurrence of the spore-forming foodborne pathogen Clostridium perfringens during rearing and consecutive processing of the larvae, based on observations in a single rearing facility. C. perfringens vegetative cells and spores were determined, in addition to total viable counts, total aerobic spore counts and intrinsic parameters including pH, water activity and moisture content. All samples were obtained from an industrial production plant. In a preliminary experiment, substrate ingredients and dried larvae were analysed, but the larvae were produced with a previous batch of the substrate mixture. A second, more detailed, experiment was performed where all samples were collected sequentially from the same production run (substrate ingredients, substrate mixture, starting larvae, harvested larvae, residue, dried larvae and stored dried larvae). In the two experiments, (presumptive) C. perfringens, as determined on tryptose sulphite cycloserine agar, was found at low numbers in the ingredients and in the second experiment it was also found in the substrate mixture. Over the two experiments, total C. perfringens counts (i.e. vegetative cells plus spores) ranged between 3.0±0.1 and

Zoophytophagous predators of the family Miridae (Heteroptera), which feed both on plant and prey, often maintain a close relationship with certain host plants. In this study, we aimed to select a suitable mirid predatory bug for aphid control in sweet pepper. Four species were compared: Macrolophus pygmaeus (Rambur), Dicyphus errans (Wolff), Dicyphus tamaninii Wagner and Deraeocoris pallens (Reuter). They were assessed on their establishment on sweet pepper plants with and without supplemental food (eggs of the flour moth Ephestia kuehniella Zeller and decapsulated cysts of the brine shrimp Artemia franciscana Kellogg) and on their effects on aphids with releases before and after aphid infestations. None of the predator species was able to control an established population of aphids on sweet pepper plants; however, the predators M. pygmaeus and D. tamaninii could successfully reduce aphid populations when released prior to an artificially introduced aphid infestation. The best results were achieved with M. pygmaeus in combination with a weekly application of supplemental food. Hence, our results demonstrate that the order and level of plant colonization by mirid predators and aphids determines how successful biological control is. Further studies are needed to evaluate the performance of mirid predatory bugs in sweet pepper crops in commercial greenhouses with multiple pests and natural enemies, in particular to understand how increased variation in food sources affects their feeding behaviour and preferences.

A new approach to β-delayed neutron spectroscopy has been demonstrated that circumvents the many limitations associated with neutron detection by instead inferring the decay branching ratios and energy spectra of the emitted neutrons by studying the nuclear recoil. Using the Beta-decay Paul Trap, fission-product ions were trapped and confined to within a 1 -mm 3 volume under vacuum using only electric fields. Results from recent measurements of 137 I + and plans for development of a dedicated ion trap for future experiments using the intense fission fragment beams from the Californium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne National Laboratory are summarized. The improved nuclear data that can be collected is needed in many fields of basic and applied science such as nuclear energy, nuclear astrophysics, and stockpile stewardship.

The β - decay Paul trap is a linear radiofrequency-quadrupole ion trap that has been developed for precision β - decay studies. The design of the trap electrodes allows a variety of radiation detectors to surround the cloud of trapped ions. The momentum of the low-energy recoiling daughter nuclei following β decay is negligibly perturbed by scattering and is available for study. This advantageous property of traps allows the kinematics of particles that are difficult or even impossible to directly detect to be precisely reconstructed using conservation of energy and momentum. An ion-trap system offers several advantages over atom traps, such as higher trapping efficiencies and element-independent capabilities. The first precision experiment using this system is a measurement of β - decay angular correlations in the decay of 8Li performed by inferring the momentum of the neutrino from the kinematic shifts imparted to the breakup α particles. Many other β - decay studies that would benefit from a determination of the nuclear recoil can be performed with this system.

In the standard model, the weak interaction is formulated with a purely vector-axial-vector (V-A) structure. Without restriction on the chirality of the neutrino, the most general limits on tensor currents from nuclear β decay are dominated by a single measurement of the β-ν[over ¯] correlation in ^{6}He β decay dating back over a half century. In the present work, the β-ν[over ¯]-α correlation in the β decay of ^{8}Li and subsequent α-particle breakup of the ^{8}Be^{*} daughter was measured. The results are consistent with a purely V-A interaction and in the case of couplings to right-handed neutrinos (C_{T}=-C_{T}^{'}) limits the tensor fraction to |C_{T}/C_{A}|^{2}

In the standard model, the weak interaction is formulated with a purely vector-axial-vector (V-A) structure. Without restriction on the chirality of the neutrino, the most general limits on tensor currents from nuclear β decay are dominated by a single measurement of the β-ν[over ¯] correlation in ^{6}He β decay dating back over a half century. In the present work, the β-ν[over ¯]-α correlation in the β decay of ^{8}Li and subsequent α-particle breakup of the ^{8}Be^{*} daughter was measured. The results are consistent with a purely V-A interaction and in the case of couplings to right-handed neutrinos (C_{T}=-C_{T}^{'}) limits the tensor fraction to |C_{T}/C_{A}|^{2}0.011 (95.5% C.L.). The measurement confirms the ^{6}He result using a different nuclear system and employing modern ion-trapping techniques subject to different systematic uncertainties.

A measurement of the $\ensuremath{\alpha}\mathrm{\text{\ensuremath{-}}}\ensuremath{\beta}\mathrm{\text{\ensuremath{-}}}\overline{\ensuremath{\nu}}$ angular correlation in the Gamow-Teller decay $^{8}\mathrm{Li}\ensuremath{\rightarrow}^{8}\mathrm{Be}^{*}+\overline{\ensuremath{\nu}}+\ensuremath{\beta}$, $^{8}\mathrm{Be}^{*}\ensuremath{\rightarrow}\ensuremath{\alpha}+\ensuremath{\alpha}$ has been performed using ions confined in a linear Paul trap surrounded by silicon detectors. The energy difference spectrum of the $\ensuremath{\alpha}$ particles emitted along and opposite the direction of the $\ensuremath{\beta}$ particle is consistent with the standard model prediction and places a limit of 3.1% (95.5% confidence level) on any tensor contribution to the decay. From this result, the amplitude of any tensor component ${C}_{T}$ relative to that of the dominant axial-vector component ${C}_{A}$ of the electroweak interaction is limited to $|{C}_{T}/{C}_{A}|l0.18$ (95.5% confidence level). This experimental approach is facilitated by several favorable features of the $^{8}\mathrm{Li}$ $\ensuremath{\beta}$ decay and has different systematic effects than the previous $\ensuremath{\beta}\mathrm{\text{\ensuremath{-}}}\overline{\ensuremath{\nu}}$ correlation results for a pure Gamow-Teller transition obtained from studying $^{6}\mathrm{He}$ $\ensuremath{\beta}$ decay.

The Canadian Penning Trap mass spectrometer has made mass measurements of 33 neutron-rich nuclides provided by the new Californium Rare Isotope Breeder Upgrade (CARIBU) facility at Argonne National Laboratory. The studied region includes the 132Sn double shell closure and ranges in Z from In to Cs, with Sn isotopes measured out to A = 135, and the typical measurement precision is at the 100 ppb level or better. The region encompasses a possible major waiting point of the astrophysical r process, and the impact of the masses on the r process is shown through a series of simulations. These first-ever simulations with direct mass information on this waiting point show significant increases in waiting time at Sn and Sb in comparison with commonly used mass models, demonstrating the inadequacy of existing models for accurate r-process calculations., Comment: 5 pages, 3 figures, accepted to Physical Review Letters

A measurement of the α-β-ν[over ¯] angular correlation in the Gamow-Teller decay (8)Li→(8)Be(*)+ν[over ¯]+β, (8)Be(*)→α+α has been performed using ions confined in a linear Paul trap surrounded by silicon detectors. The energy difference spectrum of the α particles emitted along and opposite the direction of the β particle is consistent with the standard model prediction and places a limit of 3.1% (95.5% confidence level) on any tensor contribution to the decay. From this result, the amplitude of any tensor component C(T) relative to that of the dominant axial-vector component C(A) of the electroweak interaction is limited to |C(T)/C(A)|0.18 (95.5% confidence level). This experimental approach is facilitated by several favorable features of the (8)Li β decay and has different systematic effects than the previous β-ν[over ¯] correlation results for a pure Gamow-Teller transition obtained from studying (6)He β decay.

A novel technique for beta-delayed neutron spectroscopy has been developed using trapped radioactive ions. The neutron energy spectrum was reconstructed by measuring the time of flight (TOF) of the nuclear recoil following neutron emission, thereby avoiding all the challenges associated with neutron detection such as backgrounds from scattered neutrons and gamma rays and complicated detector-response functions. A proof-of-principle measurement was conducted on 137I+ by delivering ions from a 252Cf source, confining them in a linear Paul trap surrounded by radiation detectors, and measuring the neutron energy spectrum and branching ratio by detecting the beta and recoil ions in coincidence. Systematic effects were explored by determining the branching ratio three ways. Improvements to achieve higher detection efficiency, better energy resolution, and a lower neutron energy threshold were implemented by upgrading the detectors and optimizing the trapping apparatus. These improvements were demonstrated in a campaign of measurements including 138I, which is a standard beta-delayed neutron precursor outlined by a recent IAEA report on delayed neutron measurements.

The masses of 40 neutron-rich nuclides from Z = 51 to 64 were measured at an average precision of $\delta m/m= 10^{-7}$ using the Canadian Penning Trap mass spectrometer at Argonne National Laboratory. The measurements, of fission fragments from a $^{252}$Cf spontaneous fission source in a helium gas catcher, approach the predicted path of the astrophysical $r$ process. Where overlap exists, this data set is largely consistent with previous measurements from Penning traps, storage rings, and reaction energetics, but large systematic deviations are apparent in $\beta$-endpoint measurements. Differences in mass excess from the 2003 Atomic Mass Evaluation of up to 400 keV are seen, as well as systematic disagreement with various mass models., Comment: 15 pages, 16 figures. v2 updated, published in Physical Review C

The reaction paths of two proposed nucleosynthetic processes on the proton-rich side of stability, the $rp$ and $\ensuremath{\nu}p$ processes, pass through a region of isotopes between Mo and Pd where masses had long gone unmeasured. Precise knowledge of the paths and final abundances of these two processes has been limited by the corresponding lack of precision in the proton-separation energies ${S}_{p}$ when derived from extrapolated masses. The masses of 18 neutron-deficient isotopes of Nb, Mo, Tc, Ru, and Rh have been measured using the Canadian Penning trap mass spectrometer. Three of the masses presented, ${}^{90}$Mo, ${}^{91}$Mo, and ${}^{93}$Tc, provide the first direct measurement of the masses of these nuclides, and the others provide confirmation of recent measurements using other Penning traps. Included in this work is a measurement of the mass of ${}^{87}$Mo, which differs by $3.7\ensuremath{\sigma}$ from the mass presented in the 2003 Atomic Mass Evaluation. This leads to a change in the ${S}_{p}$ value of ${}^{88}$Tc which reduces the suppression of flow of the $\ensuremath{\nu}p$-process path through ${}^{87}$Mo($p,\ensuremath{\gamma}$)${}^{88}$Tc reported following the mass measurement of ${}^{88}$Tc [C. Weber et al., Phys. Rev. C 78, 054310 (2008)]. This in turn affects the resulting $\ensuremath{\nu}p$-process abundances.

The double-{beta}-decay Q values of {sup 130}Te, {sup 128}Te, and {sup 120}Te have been determined from parent-daughter mass differences measured with the Canadian Penning Trap mass spectrometer. The {sup 132}Xe-{sup 129}Xe mass difference, which is precisely known, was also determined to confirm the accuracy of these results. The {sup 130}Te Q value was found to be 2527.01{+-}0.32 keV, which is 3.3 keV lower than the 2003 Atomic Mass Evaluation recommended value and is consistent with another recent Penning trap measurement. The {sup 128}Te and {sup 120}Te Q values were found to be 865.87{+-}1.31 and 1714.81{+-}1.25 keV, respectively. For {sup 120}Te, this reduction in uncertainty of nearly a factor of 8 opens up the possibility of using this isotope for sensitive searches for neutrinoless double-electron capture and electron capture with {beta}{sup +}emission.

The proposed {nu}p process, which occurs in the early time proton-rich neutrino winds of core-collapse supernovae, has the potential to resolve the long-standing uncertainty in the production of the light p-nuclei {sup 92}Mo and {sup 94}Mo. A recent study incorporating this {nu}p process has indicated that the proton separation energy S{sub p} of {sup 93}Rh is especially important in determining the relative production of these two isotopes. To reproduce the observed solar {sup 92}Mo/{sup 94}Mo abundance ratio of 1.57 a S{sub p} value for {sup 93}Rh of 1.64 {+-} 0.1 MeV is required. The previously unknown masses of {sup 92}Ru and {sup 93}Rh have been measured with the Canadian Penning Trap mass spectrometer resulting in an experimental value for S{sub p}({sup 93}Rh) of 2.007 {+-} 0.009 MeV. This implies that with our current understanding of the conditions in core-collapse supernova explosions the {nu}p process is not solely responsible for the observed solar {sup 92}Mo/{sup 94}Mo abundance ratio.

Lack of quality control procedures during the mass production of natural enemies may lead to failures in biological pest control. An example is presented of deteriorating efficiency of a natural enemy before quality control was applied and the measures that were taken to restore quality. Although some producers of beneficial insects and mites have applied quality control in one form or another for more than 30 years, it was only during the past 10 years that collaboration between researchers and the biocontrol industry resulted in the development of the 30 harmonized quality control guidelines that are presented in this chapter. Most guidelines have been ring-tested by commercial producers; some are still in development. For each natural enemy the test conditions and the quality control criteria are given. Finally, future developments in quality control are discussed, such as the need to develop flight and performance tests, and the wish of farmers to obtain a set of simple tests for quality control of natural enemies once they have arrived at the farm.