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Improved neutron inelastic scattering cross section data are needed to inform integral benchmark studies and advance applications in a wide variety of areas including nuclear energy, stockpile stewardship, nonproliferation, and space exploration. Neutron inelastic scattering also serves as a non-selective probe of low-lying nuclear structure. To help meet these needs, the Gamma Energy Neutron Energy Spectrometer for Inelastic Scattering (GENESIS) was constructed at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. This array couples high-resolution γ -ray detectors and fast neutron detectors to achieve single and coincident n/ γ detection over a broad energy range. The current configuration of the array includes 26 organic liquid scintillators and four high-purity germanium detectors (two single-crystal and two four-crystal CLOVER detectors with two-fold segmentation). The array was constructed with minimal supporting material and designed to cover a wide range of secondary particle angles and energies with limited inter-element scattering. Data acquisition is accomplished using Mesytec MDPP-16 multi-channel high-resolution digital pulse processing modules. The array characteristics, including γ -ray and neutron energy resolution, timing resolution, and detection efficiency were measured and used to validate a Geant4 model of the array. The primary sources of neutron background and the uncertainties in the determination of incident and secondary neutron energy were assessed. GENESIS provides a new capability to address nuclear data needs and facilitates the advancement of a wide range of nuclear applications. [ABSTRACT FROM AUTHOR]

The proton light yield of organic scintillators has been measured extensively in recent years using fast waveform digitizers and large discrepancies exist in the values reported by different authors. In this letter, we address principles of digital signal processing that must be considered when conducting scintillator light yield measurements. Digitized waveform pulse height values are only proportional to the amount of scintillation light if the temporal shape of the scintillation pulse is independent of the amount of energy deposited. This is not the case for scintillation pulses resulting from fast neutron interactions in organic scintillators. Authors measuring proton light yield should therefore report pulse integral values and ensure that the integration length is long enough to capture most of the scintillation light. [ABSTRACT FROM AUTHOR]

Compact neutron imagers using double-scatter kinematic reconstruction are being designed for localization and characterization of special nuclear material. These neutron imaging systems rely on scintillators with a rapid prompt temporal response as the detection medium. As n–p elastic scattering is the primary mechanism for light generation by fast neutron interactions in organic scintillators, proton light yield data are needed for accurate assessment of scintillator performance. The proton light yield of a series of commercial fast plastic organic scintillators – EJ-200, EJ-204, and EJ-208 – was measured via a double time-of-flight technique at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. Using a tunable deuteron breakup neutron source, target scintillators housed in a dual photomultiplier tube configuration, and an array of pulse-shape-discriminating observation scintillators, the fast plastic scintillator light yield was measured over a broad and continuous energy range down to proton recoil energies of approximately 50 keV. This work provides key input to event reconstruction algorithms required for utilization of these materials in emerging neutron imaging modalities. [ABSTRACT FROM AUTHOR]

Abstract An energy tuning assembly (ETA) was designed to be fielded at the National Ignition Facility (NIF) to modify the characteristic D-T fusion spectrum to include a prompt fission neutron spectral component. The ETA was characterized at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory to measure the shaped spectrum from an incident deuteron breakup neutron source, test the proposed neutron spectroscopy techniques used to inform the flux measurements at NIF, and validate the ability to predict ETA performance using a Monte Carlo Neutral Particle (MCNP) simulation. Activation foils (i.e., Ni, In, Au, Al) were exposed to a collimated 33-MeV deuteron-breakup beam originating from a tantalum breakup target. The source spectrum absent the ETA was characterized using a set of activation foils and the STAYSL unfolding code. Finally, the ETA-modified spectrum was obtained using activation foil unfolding with a χ 2 ν = 0. 92. The ETA-modified unfolded spectrum agreed with the MCNP-simulated prediction in the energy range of 0.1–14 MeV, but exhibited disagreements in the 10 eV–100 keV region. This work demonstrates shaping of the NIF neutron spectrum via the ETA to be a viable path forward for tailored neutron beams at NIF. [ABSTRACT FROM AUTHOR]

A new software package, the Fission Induced Electromagnetic Response (FIER) code, has been developed to analytically predict delayed γ -ray spectra following fission. FIER uses evaluated nuclear data and solutions to the Bateman equations to calculate the time-dependent populations of fission products and their decay daughters resulting from irradiation of a fissionable isotope. These populations are then used in the calculation of γ -ray emission rates to obtain the corresponding delayed γ -ray spectra. FIER output was compared to experimental data obtained by irradiation of a 235 U sample in the Godiva critical assembly. This investigation illuminated discrepancies in the input nuclear data libraries, showcasing the usefulness of FIER as a tool to address nuclear data deficiencies through comparison with experimental data. FIER provides traceability between γ -ray emissions and their contributing nuclear species, decay chains, and parent fission fragments, yielding a new capability for the nuclear science community. [ABSTRACT FROM AUTHOR]

While past neuroimaging methods have contributed greatly to our understanding of brain function after traumatic brain injury (TBI), resting state functional MRI (rsfMRI) connectivity methods have more recently provided a far more unbiased approach with which to monitor brain circuitry compared to task-based approaches. However, current knowledge on the physiologic underpinnings of the correlated blood oxygen level dependent signal, and how changes in functional connectivity relate to reorganizational processes that occur following injury is limited. The degree and extent of this relationship remain to be determined in order that rsfMRI methods can be fully adapted for determining the optimal timing and type of rehabilitative interventions that can be used post-TBI to achieve the best outcome. Very few rsfMRI studies exist after experimental TBI and therefore we chose to acquire rsfMRI data before and at 7, 14 and 28 days after experimental TBI using a well-known, clinically-relevant, unilateral controlled cortical impact injury (CCI) adult rat model of TBI. This model was chosen since it has widespread axonal injury, a well-defined time-course of reorganization including spine, dendrite, axonal and cortical map changes, as well as spontaneous recovery of sensorimotor function by 28 d post-injury from which to interpret alterations in functional connectivity. Data were co-registered to a parcellated rat template to generate adjacency matrices for network analysis by graph theory. Making no assumptions about direction of change, we used two-tailed statistical analysis over multiple brain regions in a data-driven approach to access global and regional changes in network topology in order to assess brain connectivity in an unbiased way. Our main hypothesis was that deficits in functional connectivity would become apparent in regions known to be structurally altered or deficient in axonal connectivity in this model. The data show the loss of functional connectivity predicted by the structural deficits, not only within the primary sensorimotor injury site and pericontused regions, but the normally connected homotopic cortex, as well as subcortical regions, all of which persisted chronically. Especially novel in this study is the unanticipated finding of widespread increases in connection strength that dwarf both the degree and extent of the functional disconnections, and which persist chronically in some sensorimotor and subcortically connected regions. Exploratory global network analysis showed changes in network parameters indicative of possible acutely increased random connectivity and temporary reductions in modularity that were matched by local increases in connectedness and increased efficiency among more weakly connected regions. The global network parameters: shortest path-length, clustering coefficient and modularity that were most affected by trauma also scaled with the severity of injury, so that the corresponding regional measures were correlated to the injury severity most notably at 7 and 14 days and especially within, but not limited to, the contralateral cortex. These changes in functional network parameters are discussed in relation to the known time-course of physiologic and anatomic data that underlie structural and functional reorganization in this experiment model of TBI. [ABSTRACT FROM AUTHOR]

To determine the safety of using argon as a deuteron beam stopping material, the 40Ar(d,p)41Ar cross section was measured at average deuteron energies of 3.6 MeV, 5.5 MeV, and 7.0 MeV using an activation method. A 16-MeV deuteron beam produced by Lawrence Berkeley National Laboratory's 88-Inch Cyclotron was degraded to each energy by nickel foils and the front wall of an aluminum gas chamber. The reduced-energy deuterons were used to activate a sample of n a t Ar gas. After each irradiation, the gas chamber's 41Ar activation was measured with a high-purity germanium detector. The cross sections measured were larger than a previous measurement by ∼ 40%. • We measured the 41Ar(d,p)40Ar cross section at 3.6, 5.5 and 7.0 MeV using an activation method. • Our measured cross section was significantly higher than both a previous measurement and TENDL. • Without significant shielding, argon is not recommended as a deuteron beam stopping medium. [ABSTRACT FROM AUTHOR]

Pigs are often transported to slaughter under conditions outside their thermo-neutral zones, which can lead to reduced welfare and increased losses. Water sprinkling in barns is used to control microclimate resulting in pig body temperature reduction and improved welfare; however there is no clear evidence of these effects during transport. The aim of this study was to observe the effect of sprinkling pigs in trailers on behaviour and body temperature during transport and lairage, as well as to observe the effects on trailer microclimate. In each of 12 weeks, 2 pot-belly trailers with 208 pigs each (n=4992) were transported from the same farm on the same day 2h to slaughter. One trailer was equipped with sprinklers that ran for 5min (~125L) before departure and before unloading, the other trailer served as the control. In each trailer, 4 compartments were outfitted with cameras, ammonia detectors and temperature/humidity data loggers. The gastrointestinal tract temperature (GTT; °C) of 4 randomly chosen pigs (n=384) in each test compartment was recorded using orally administered data loggers. Trailer and deck loading order were randomized. Behaviour during transport, unloading and lairage was recorded from video or live observations. Data were analysed through ANOVA with ambient temperature external to the trailer (AmbT) as a covariate. AmbT averaged 19.5°C±3.8°C (range: 13.6–25.8°C). Sprinkled trailers showed lower (P=0.002) increases in internal compartment temperature from loading to unloading, smaller (P<0.001) decreases in humidity and no difference in ammonia levels. At AmbT>23°C, there was no effect of sprinkling on behaviour on the trailer, but at AmbT<23°C, more pigs stood on sprinkled trailers (P<0.05). Sprinkling did not affect slips or falls during unloading. In lairage, latency to rest was reduced as AmbT increased for all compartments (P<0.05); sprinkled pigs spent more time lying (P<0.05) and had fewer drinking bouts than controls (P<0.001) regardless of AmbT. GTT increased between loading and departure and decreased during transit for all pigs (P<0.001); and sprinkling tended to further reduce GTT at arrival at AmbT>24°C (P=0.08). These data suggest that sprinkling pigs in a stationary vehicle when AmbT exceeds 23°C has the potential to prevent increases in body temperature during short duration transport without detrimental effects on ammonia levels or behaviour during unloading. [ABSTRACT FROM AUTHOR]

Abstract: A sequence of daily beach surveys acquired over one month covering an area larger than 100,000m2, was analyzed to study morphological changes resulting from a cluster of storms. The beach response was highly variable in both the cross- and alongshore. A cumulative storm effect was not observed, despite one storm being characterized by a 10-year return period that had significant wave height (Hs) of 8.1m and a peak wave period (Tp) of 17s. Instead, storms that can potentially cause significant erosion in terms of Hs had a limited effect on the morphology because the large wave height was coupled to either neap tides, normally-incident short-waves (f >0.04Hz), or low levels of infragravity (0.004< f <0.04Hz) energy. Multiple linear regression analysis shows that volumetric changes in the upper part of the beachface are explained by offshore wave characteristics (period, height and direction), tidal range or by infragravity energy in the inner surf zone (assessed using pressure and velocity measurements). The results indicate that it is not possible to scale-up single-storm erosion studies into predictions of cluster-storm erosion. [Copyright &y& Elsevier]

Throughout the world, the invasion of alien plants is an increasing threat to native biodiversity. Invasion is especially prevalent in areas affected by land transformation and anthropogenic disturbance. Surface mines are a major disturbance, and thus may promote the establishment and expansion of invasive plant communities. Environmental and habitat factors that may contribute to favourable conditions for heightened plant invasion were examined using the Shale Hills region (SHR) of Alabama as a case study. Overall the invasive community was predominantly associated with forest structure and composition. At an individual species level, forest structure and composition also dominated models; however, soil characteristics were also integrated. The influence of planting alien, invasive species in this area is likely the major driver of the high diversity of invasive plants, with three of the six dominant species being planted. Adjusting the reclamation plantings to native species would aid in reducing the number and diversity of invasive plants. Overall, it appears that the initial reclamation efforts, apart from the planting of alien species, are not the major driver impacting the invasive plant composition of the reclaimed, now forested mine sites. [ABSTRACT FROM PUBLISHER]

The objective of this review is to discuss the less common causes of rectal and perirectal disease with an emphasis on their differentiating radiological features and the importance of a multimodality imaging approach. Radiologists should be aware of the ultrasound, computed tomography, and magnetic resonance imaging appearances of the wide variety of uncommon lesions arising from the rectal and perirectal regions that may simulate adenocarcinoma in order to render an accurate diagnosis and facilitate appropriate management. [Copyright &y& Elsevier]

Abstract: Intermediate-energy projectile Coulomb excitation of the unstable nucleus 18Fg.s. and its short-lived E x=1.1MeV (J π=5+) isomeric state (t 1/2=162ns) 18Fm have been studied at 30MeV per nucleon. Radioactive beams of 18Fg.s. and 18Fm nuclei were produced by nucleon transfer on a carbon production target and delivered to a secondary 197Au target for Coulomb excitation. Photons emitted in the vicinity of the 197Au target were detected in a large-solid-angle position-sensitive NaI(Tl) array, which allowed for the identification of the beam and target excited states populated by intermediate-energy Coulomb excitation. Two possible 18F ground-state excitations were identified, and B(Eλ↑) values were deduced. Upper limits were established for reduced transition probabilities B(E1↑) and B(E2↑) of several predicted transitions from the 18Fm isomeric state, 5+→4+, 4−, 3+, and compared with values inferred from γ-decay lifetimes. An indication of an enhanced in-flight isomer decay, possibly due to the Coulomb interaction with the target is observed and discussed. The special detector configurations and analytical techniques needed for these types of measurements are described together with suggested improvements. [Copyright &y& Elsevier]

The discovery, synthesis and biological activity of a series of triarylethane phosphodiesterase 4 inhibitors is described. Structure–activity relationship studies are presented for CDP840 (29), a potent, chiral, selective inhibitor of PDE 4 (IC50 4 nM). CDP840 is non-emetic in the ferret at 30 mg kg−1 (po), active in models of inflammation and reverses ozone-induced bronchial hyperreactivity in the guinea pig. [Copyright &y& Elsevier]