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Abstract: Predicting the potential distribution of invasive plants within a specific region is pivotal to planning effective management but is challenged by attempting to model expanding populations that are rarely at equilibrium with their environment. We adopt an ensemble modelling approach to assess the potential distribution of Japanese honeysuckle (Lonicera japonica), a vine invasive to forests of the Cumberland Plateau and Mountain Region in the southeast of USA. The influence of disturbance, spatial and temporal heterogeneity and other landscape characteristics were assessed by creating regional level models based on occurrence records from the United States Department of Agriculture, Forest Service, Forest Inventory and Analysis (FIA) database. Logistic regression and maximum entropy (MaxEnt) models were assessed independently and evaluated as predictive tools to test the value of presence/absence and presence only data in predicting species distributions. Ensemble models were also developed that combined the predictions of the two modelling approaches to obtain a more robust prediction. While logistic and MaxEnt models were similar in their predictive ability and dominant input variables, the ensemble approach derived the best fitting model overall. The regional distribution of Japanese honeysuckle was influenced greatly by environmental conditions such as elevation, slope, and temperature with anthropogenic activity having significant, though lesser, influence. The ensemble models predict that Japanese honeysuckle has nearly reached its potential distribution. However, given the critical role of minimum temperature on Japanese honeysuckle distribution, future occupancy at higher elevations is likely to increase since January temperatures for this region are predicted to rise by 1–4°C over the next 100 years. The models also give some indication of the likely effect of land cover change on its distribution. Japanese honeysuckle tended to be associated with a high component of farming or low component of forest within the local neighbourhood. This suggests disturbed forest and/or high fragmentation has a higher invasion potential and given past trends and expected continued population growth this disturbance and fragmentation will only increase. The models can be integrated into forest management decision support systems and assist in the development of long term management plans, integrating the impact of potential climate and land cover change scenarios. [Copyright &y& Elsevier]

Abstract: Through computer simulations, we show that plasticity in twinned copper nanopillars can be either reversible or irreversible depending on the applied stress state. Copper nanopillars, containing twinned crystals, are subjected to both compression and tension, and the ratio of the resolved shear to the normal stress , R, is adjusted through variation of the orientation of the twin boundary plane with respect to the loading axis. It is found that the yield locus on the plane for twinned nanopillars is asymmetric with respect to the sign of R. For a 9nm diameter copper nanopillar under compression, plastic deformation can be totally reversed when is in the range , with a corresponding increase in the compressive normal stress, up to ≈2.5GPa. It is shown that these conditions are achieved for axial strains <3.3%, and that the transition to plastic irreversibility takes place at larger strains or normal stresses. The mechanism responsible for the plastic reversible–irreversible transition is shown to be a competition between the nucleation of Shockley partial dislocations at the nanopillar surface for irreversible plasticity vs. twinning dislocations for reversible plasticity. Furthermore, the speed of Shockley partials at twin boundaries is subsonic when there is either tension or compression acting on the twin boundary, and slightly supersonic when only shear is applied. [Copyright &y& Elsevier]

Abstract: The atomic mechanisms of twin boundary migration in copper under externally applied mechanical loads and during thermal annealing are investigated utilizing molecular dynamics computer simulations. The migration dynamics of the incoherent twin boundary (ITB), pinned between two twin boundaries, is determined. A three-dimensional structural model is described for the junction between intersecting coherent and incoherent twin boundaries, and migration velocities are calculated under thermal annealing conditions. It is shown that the coherent twin boundary (CTB)/ITB junction results in breaking the crystal symmetry by creation of either an edge dislocation or a mixed (edge/screw) at the intersection. These two types of defects can lead to pronounced differences in the observed migration (and hence annealing) rates of ICT/CTB junctions. The annealing rate resulting from the migration of ITBs with a mixed dislocation is found to be more than twice that of the edge dislocation. The mechanism of ITB motion is shown to be governed by successive kink-like motion of neighboring atomic columns, each of which is shifted by 1/4[110], followed by structural relaxation to accommodate boundary motion. [Copyright &y& Elsevier]

Abstract: We present the results of molecular dynamics computations based on the atomic resolution structure of tubulin. Values of net charge, charge distribution and dipole moment components are obtained for the tubulin heterodimer. Physical consequences of these results are discussed for microtubules in terms of the effects on test charges, test dipoles, and neighboring microtubules. [Copyright &y& Elsevier]

Abstract: Grain boundary structure and grain boundary segregation in stoichiometric and Ni-rich compositions of NiAl are studied by molecular statics and grand-canonical Monte-Carlo simulations in conjunction with an embedded-atom potential. Significant Ni segregation is found at the Σ =3(111) and Σ =3(211) grain boundaries, with segregation isotherms showing a saturation effect. The amount of Ni segregation increases and the excess free energy of the grain boundaries decreases with increased Ni bulk concentration. In strongly Ni-rich bulk compositions, both boundaries undergo transformations to new structures capable of accommodating more excess Ni atoms than the initial structures. The structural transformation is clearly manifested by a non-monotonic behavior of the segregation isotherm. In the Σ =3(211) grain boundary, the transformation is accompanied by a relative tangential translation of the grains. [Copyright &y& Elsevier]

We have applied a Hubbard model to a triangular lattice and found that this coordination yields surprising results relative to its rectangular lattice counterpart. A Drude peak arises when a third hopping direction is added and the degree of coordination increases. A similar effect is noted when periodic boundary conditions are applied in the lateral direction, creating a tube from the otherwise flat lattice. [Copyright &y& Elsevier]

Our understanding of the role of the parabrachial nucleus (PBN) has evolved as technology has advanced, in part due to cell-specific studies and complex behavioral assays. This is reflected in the heterogeneous neuronal populations within the PBN to the extended amygdala (EA) circuits which encompass the bed nucleus of the stria terminalis (BNST) and central amygdala (CeA) circuitry, as they differentially modulate aspects of behavior in response to diverse threat-like contexts necessary for survival. Here we review how the PBN→CeA and PBN→BNST pathways differentially modulate fear-like behavior, innate and conditioned, through unique changes in neurotransmission in response to stress-inducing contexts. Furthermore, we hypothesize how in specific instances the PBN→CeA and PBN→BNST circuits are redundant and in part intertwined with their respective reciprocal projections. By deconstructing the interoceptive and exteroceptive components of affect- and stress related behavioral paradigms, evidence suggests that the PBN→CeA circuit modulates innate response to physical stimuli and fear conditioning. Conversely, the PBN→BNST circuit modulates distress-like stress in unpredictable contexts. Thereby, the PBN provides a pathway for alarming interoceptive and exteroceptive stimuli to be processed and relayed to the EA to induce stress-relevant affect. Additionally, we provide a framework for future studies to detail the cell-type specific intricacies of PBN→EA circuits in mediating behavioral responses to threats, and the relevance of the PBN in drug-use as it relates to threat and negative reinforcement. This article is part of the special Issue on 'Neurocircuitry Modulating Drug and Alcohol Abuse'. • Parabrachial to extended amygdala circuit (PBN.→EA) modulates stress-related consumption. • PBN.→EA modulates innate and learned fear behavior. • PBN.→EA activity is dysregulated in visceral and somatosensory disorders. • PBN.→EA driven behavior and transmission is sensitive to chronic stress. • Stress-like behavior driven by PBN.→EA is relevant to drug-related negative-affect. [ABSTRACT FROM AUTHOR]

The influence of the central circadian clock on reproductive timing is well established. Much less is known about the role of peripheral oscillators such as those in the ovary. We investigated the influence of photoperiod and timing of the LH surge on expression of circadian clock genes and genes involved in steroidogenesis in ovine ovarian stroma. Seventy-two Suffolk cross ewes were divided into two groups, and their estrous cycles were synchronized. Progestagen sponge removal was staggered by 12 hours between the groups such that expected LH peak would occur midway through either the light or dark phase of the photoperiodic cycle. Four animals from each group were killed, and their ovaries were harvested beginning 36 hours after sponge removal, at 6-hour intervals for 48 hours. Blood was sampled every 3 hours for the period 24 to 48 hours after sponge removal to detect the LH surge. The interval to peak LH did not differ between the groups (36.2 ± 1.2 and 35.6 ± 1.1 hours, respectively). There was an interaction between group and the time of sponge removal on the expression of the core clock genes ARNTL , PER1 , CRY1 , CLOCK , and DBP (P < 0.01, P < 0.05, P < 0.01, P < 0.01, and P < 0.01, respectively). As no significant interaction between group and time of day was detected, the datasets were combined. Statistically significant rhythmic oscillation was observed for ARNTL , CLOCK , CRY1 (P < 0.01, respectively), PTGS2 , DBP , PTGER2 , and CYP17A1 (P < 0.05, respectively), confirming the existence of a time-sensitive functionality within the ovary, which may influence steroidogenesis and is independent of the ovulatory cycle. [ABSTRACT FROM AUTHOR]

Several studies have shown that food ration can affect the growth of cultured fish. Determining the optimal food ration would help to achieve better growth and also provide direct economic benefits due to reduced food wastage, which would lead to commercial success. Therefore, we studied the effects of ration levels on growth performance of 0+ juvenile yellowtail flounder to determine the optimal food ration. Two experiments were conducted; the first experiment as a preliminary using ration levels of 1%, 2%, 4%, 6% body weight per day (% bw day−1) held at 7.0 °C with a stocking density of 0.95 kg m−2 (∼45% bottom coverage). Results of this preliminary experiment indicated that fish fed with 1% bw day−1 had significantly lower growth (weight, length, body depth and specific growth rates (SGR)) than those fed with 2%, 4% and 6% ration. However, fish fed with rations of 1% and 2% showed significantly lower gross food conversion ratios (GFCR) than fish fed with 4% and 6% rations. Survival was not significantly affected by different ration levels. Based on these preliminary results, we used ration levels of 1%, 1.5%, 2% and 3% for the main experiment. Fish were held at 10 °C with a stocking density of 1.45 kg m−2 (∼34% bottom coverage). Results indicated that fish fed with 1%, 1.5% and 2% bw day−1 had significantly lower growth than fish fed with 3% bw day−1. GFCR was significantly different for all four rations. It was lower for 1% than 1.5%, 2% and 3% rations. Survival was not significantly different between any treatments. We discuss our results with emphasis on growth and economics (i.e., feed wastage) and stress the need to balance both components in a commercial operation. [Copyright &y& Elsevier]

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]

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]