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Discusses a theoretical calculation of the spectrum of the argon-methane complex based upon a previous ab initio potential energy surface. Proper rotation matrices used in the study; Body-fixed Hamiltonian describing the complex; Symmetry adaptation used in the study; Interaction of the complex with the laser; Bound states of AR-CH[sub 4].

Examines the characterization of nonadditive interactions in van der Waals molecules using symmetry-adapted perturbation theory of three-body surfaces. Multipole-expanded expressions for the induction, induction-dispersion and dispersion nonadditivities; Significance of exchange quadrupole electrostatic interaction.

Reports on density functional calculations of molecular g-tensors in the zero-order regular approximation for relativistic effects. Consideration of spin-orbit coupling using the zero-order regular approximation to the Dirac equation; Solution for the problem of gauge dependence.

We previously demonstrated that domestic hens, Gallus gallus domesticus, show behavioural and physiological responses when witnessing mild chick distress, and possess the underlying foundations of emotional empathy. However, no studies have determined how cognitive influences affect empathic processes in birds. A fundamental question is whether a mother hen's response to chick distress is mediated by her knowledge about the situation or by chick distress cues. We therefore investigated how manipulating hen and chick knowledge influences hens' responses to chick distress. Each hen's brood of chicks was split into three groups, based on whether they had the same, opposite or no knowledge about a potentially threatening situation (environmental cues signalling air puff administration). We compared hens' behavioural, vocal and physiological responses (heart rate, heart rate variability and surface body temperature) to actual and perceived threat to their chicks. Hens increased maternal vocalizations and walking, and decreased preening, when they perceived their chicks to be threatened, regardless of the chicks' reactions to the situation. Hens exhibited signs of stress-induced hyperthermia only when their perception of threat was in accordance with that of their chicks. Chick behaviour was influenced by the hens' expectations, with all chick groups spending more time distress vocalizing and less time preening when in the environment that the hen associated with threat. We conclude that the protective maternal response of domestic hens is not solely driven by chick distress cues; rather, hens integrate these with their own knowledge to produce a potentially adaptive, flexible and context-dependent response. [ABSTRACT FROM AUTHOR]

Abstract: One of the first fusion–evaporation experiments using radioactive ion beams was performed at GANIL in order to study proton-rich nuclei of the light rare-earth region. The low production cross-section of the exotic species of interest, in combination with the low intensity of the beam and its induced background, demanded the use of a highly efficient experimental setup. This consisted of the EXOGAM -ray spectrometer coupled for the first time with both the DIAMANT charged-particle array and the VAMOS recoil spectrometer. In this report the experimental challenges of such studies will be discussed and the experimental achievements of the in-beam spectroscopy of proton drip-line nuclei using EXOGAM will be presented. [Copyright &y& Elsevier]

Abstract: Three strongly coupled sequences have been established in 110,112Te up to high spins. They are interpreted in terms of deformed structures built on proton 1-particle–1-hole excitations that reach termination at . This is the first observation of smooth terminating dipole structures in this mass region. Lifetime measurements have allowed the extraction of experimental and reduced transition rates for one of the dipole bands in 110Te. The results support the deformed interpretation. [Copyright &y& Elsevier]

Deals with the relation between molecular potentials and the spectra of van der Waals molecules and hydrogen-bonded complexes. Calculation of spectra of van der Waals molecules; Rovibrational spectrum of argon-methane; Water pair potential and dimer spectrum.

An expression for the nonadditive first-order exchange contribution in terms of the one- and two-particle density matrices of the isolated monomers is given. This formula is used to derive the intramonomer correlation contribution to the first-order exchange nonadditivity with the density matrices of the isolated monomers computed at the second-order Møller-Plesset level. As an illustrative example of the theory the trimer Ar[sub 2]-HF is considered. It is shown that the correlation contribution is far from negligible, not only in relation to the corresponding first-order uncorrelated exchange, but also in comparison to the other three-body terms. Moreover, it is fairly anisotropic, so that it cannot be neglected in accurate calculations of nonadditive effects. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Calculates the intermolecular potential energy surface of the He-CO complex including the CO bond length dependence using symmetry-adapted perturbation theory. Potential minimum when the molecular bond length is fixed at an equilibrium value; Application of the potential in the calculation of bound state levels and the infrared spectrum for the complexes.

Studies the total differential cross sections and differential energy loss spectra for He-C[sub2]H[sub2] from an ab initio potential. Scattering obtained; Accuracy of the symmetry-adapted perturbation theory.

Intermediate energy single-neutron removal from 31 Mg has been employed to investigate the transition into the N = 20 island of inversion. Levels up to 5 MeV excitation energy in 30 Mg were populated and spin-parity assignments were inferred from the corresponding longitudinal momentum distributions and γ -ray decay scheme. Comparison with eikonal-model calculations also permitted spectroscopic factors to be deduced. Surprisingly, the 0 2 + level in 30 Mg was found to have a strength much weaker than expected in the conventional picture of a predominantly 2 p − 2 h intruder configuration having a large overlap with the deformed 31 Mg ground state. In addition, negative parity levels were identified for the first time in 30 Mg, one of which is located at low excitation energy. The results are discussed in the light of shell-model calculations employing two newly developed approaches with markedly different descriptions of the structure of 30 Mg. It is concluded that the cross-shell effects in the region of the island of inversion at Z = 12 are considerably more complex than previously thought and that n p − n h configurations play a major role in the structure of 30 Mg. [ABSTRACT FROM AUTHOR]

Two new negative-parity bands have been identified in the odd-odd 104Rh nucleus. According to their experimentally observed properties, they have the same π (1 g 9 / 2) − 1 ⊗ ν (1 h 11 / 2) 1 high- j configuration as the previously known negative-parity chiral doublet bands. This observation raises the possibility of the existence of multiple chiral doublet bands, M χ D, in this nucleus. Comparing the properties of the observed bands with results of detailed theoretical calculations, one can conclude that the lower energy parts of bands 1 and 2 are chiral partner bands with the π (1 g 9 / 2) − 1 ⊗ ν (1 h 11 / 2) 1 two-quasiparticle configuration, while bands 3 and 4 are chiral partner bands with the π (1 g 9 / 2) − 1 ⊗ ν (1 g 7 / 2) − 2 (1 h 11 / 2) 1 four-quasiparticle configuration. Thus, M χ D based on different configurations is observed in 104Rh. [ABSTRACT FROM AUTHOR]

A symmetry-adapted perturbation theory (SAPT) is formulated for interaction-induced electrical properties of weakly bound complexes. Asymptotic (large R) expressions are reported for the contributions to the collision-induced dipole moments and polarizabilities up to and including second order in the intermolecular potential. These long-range expressions require knowledge only of the multipole moments and (hyper)polarizabilities of the isolated monomers. Numerical results are given for the dipole moment of He-H2 and the polarizability of He2 and the accuracy of the SAPT approach is examined by comparison with full configuration interaction results. The role of various physical contributions to the dipole moment of He-H2 and the polarizability of He2 is investigated. The validity of the long-range approximation and the importance of charge penetration (damping) effects are discussed. [ABSTRACT FROM AUTHOR]

While research has started to contest traditional student-supervisor power asymmetries within work-integrated learning, substantial gaps remain about work-integrated learning feedback, power and resistance. This study explores how students and supervisors narrate student power and resistance within work-integrated learning feedback narratives. Ninety-four feedback narratives were collected from 26 higher education students and 25 supervisors from six disciplines participating in 45 interviews. Data were analysed using thematic and narrative analysis. Although the narratives often reproduced traditional power asymmetries, they also contested espoused power asymmetries. Participants reported students exercising power in feedback relationships, either of their own accord or through supervisor power-sharing. Students were also reported to enact resistance to supervisor power, sometimes resulting in supervisor undermining. Student enactment of power and resistance was also illustrated through participants' pronominal, metaphoric and identity talk. We encourage work-integrated learning students and supervisors to enhance their feedback literacy paying close attention to issues of power and resistance. Students should exercise power and resistance in productive rather than repressive ways during work-integrated learning feedback in order to avoid negative impacts for supervisor well-being and student learning. Further research is needed to explore researcher and participant identification of power and resistance across more diverse participants. [ABSTRACT FROM AUTHOR]

Abstract: Stress-induced hyperthermia (SIH) occurs in numerous species and is characterised by an increase in core body temperature, and a decrease in surface temperature, of between 0.5 and 1.5°C within 10 to 15min of the onset of “emotional stress”. The aim of the current study was to ascertain whether the husbandry-relevant procedure of handling resulted in measurable changes in surface body temperature in chickens, as measured using infrared thermography. Baseline temperatures for 19 domestic hens were compared to temperatures immediately, and up to 20min following handling (catching and brief restraint by a human). Surface head, eye and comb temperatures were plotted to investigate the pattern of temperature change. In response to handling, comb temperature decreased significantly, showing a rapid 2°C drop. Eye temperature showed an initial decrease then rose to levels significantly higher than handling. Head temperature increased over the 20min post-handling period, to reach levels significantly higher than baseline. It can be concluded that surface temperature changes assessed using infrared thermography, in particular of the hen's comb, are sensitive to husbandry procedures such as handling and represent a potentially useful method for assessing stress-induced hyperthermia in chickens. [Copyright &y& Elsevier]

Abstract: Domestic animals may be frequently exposed to situations in which they witness the distress or pain of conspecifics and the extent to which they are affected by this will depend on their capacity for empathy. Empathy encompasses two partially distinct sets of processes concerned with the emotional and cognitive systems. The term, empathy, is therefore used to describe both relatively simple processes, such as physiological and behavioural matching; and more complex interactions between emotional and cognitive perspective taking systems. Most previous attempts to measure empathic responsiveness in animals have not distinguished between responses primarily relevant to the situation of the observer and those primarily relevant to the situation of the conspecific. Only the latter can be considered empathic. However, even during well-controlled studies, behavioural or physiological responses to conspecific pain or distress may indicate nothing more than interest or arousal. To demonstrate a truly empathic response to the plight of another, experimenters must also show that a valenced (positive or negative), and therefore emotional, component is present. Such studies are vital to the fundamental question of the extent to which animals are capable of empathic responsiveness, and to determine how the welfare of domestic animals might be affected by the social environment. In this review we will consider evidence for the existence of the capacity for emotional empathy, in its broadest sense, in a variety of non-human species and offer direction on future work of relevance to the welfare implications of coping in large groups. [Copyright &y& Elsevier]

Abstract: The transition quadrupole moments, , of four weakly populated collective bands up to spin in 157,158Er have been measured to be demonstrating that these sequences are associated with large deformations. However, the data are inconsistent with calculated values from cranked Nilsson–Strutinsky calculations that predict the lowest energy triaxial shape to be associated with rotation about the short principal axis. The data appear to favor either a stable triaxial shape rotating about the intermediate axis or, alternatively, a triaxial shape with larger deformation rotating about the short axis. These new results challenge the present understanding of triaxiality in nuclei. [Copyright &y& Elsevier]

Abstract: Reducing lameness in dairy herds requires farmers to adapt or change existing practices or resources. Those who seek to improve animal welfare by influencing the actions of farmers need to understand farmers’ motivations. To investigate why farmers see lameness as a problem and what motivates their efforts to reduce lameness, a questionnaire was carried out with 222 UK dairy farmers. Farmers considered pain and suffering for the cows to be an important outcome of lameness, but reduced performance by lame cows was also seen as a considerable problem. The motivator most commonly given high importance was pride in a healthy herd. Factors incorporating accreditation issues, public image and costs of treatment were generally seen to be of some, but lesser importance. Advisors need to take all these areas into consideration when working to encourage farmers to act to reduce lameness and thereby improve animal welfare. [ABSTRACT FROM AUTHOR]

Abstract: On 222 dairy farms, the farmer’s perception of the scale of the herd lameness problem was compared with the prevalence detected by observation of the milking herd, and a questionnaire explored the barriers to lameness reduction. Ninety percent of farmers did not perceive lameness to be a major problem on their farm, although the average prevalence of lameness was 36%. For 62% of the sample, lameness was not the top priority for efforts made to improve herd health. Time and labour were important limiting factors for lameness control activities and financial constraints prevented farmers taking action on advice in 30% of cases. Farmers’ understanding the implications of lameness for the farm business was limited. Lameness reduction is restricted by farmers’ perception of lameness, but also by time, labour and finance; these issues need to be addressed at the industry level to support animal welfare improvement. [ABSTRACT FROM AUTHOR]

Abstract: Excited states have been identified in the very neutron-deficient 122Ce nucleus. This is the first observation of this nucleus and its excited states. The ground-state rotational band has been observed up to spin 14 ℏ. The band has been assigned to 122Ce by detecting gamma rays in coincidence with evaporated charged particles and neutrons. The value suggests a rather large ground-state deformation of , in good agreement with Hartree–Fock–Bogoliubov (HFB) mean-field calculations. The aligned angular momentum of the band has been studied and is compared with those of the neighboring even–even cerium isotopes, and to Woods–Saxon cranking calculations. The non-observation of the alignment until at least 0.4 MeV/ℏ is consistent with the extracted value of . [Copyright &y& Elsevier]

The collective structures of131Cs have been investigated by in-beam ?-ray spectroscopic techniques following the124Sn (^11B , 4n) reaction at a beam energyElab = 57MeV. The previously established rotational bands, built on pg7/2, pd5/2 and the unique-parity ph11/2 orbitals, have been extended and evolve into new bands involving rotationally aligned ?(h11/2)2 and p(h11/2)2 quasiparticles. In addition, a new multiquasiparticle band based on the pg7/2 ? ?g7/2 ? ?h11/2 configuration has also been observed. Theoretical interpretations for the assigned configurations are discussed in the framework of Total Routhian Surface (TRS) and Tilted Axis Cranking (TAC) model calculations. TAC model calculations predict a decrease in theB(M1) values with increasing rotational frequency for the pg7/2/pd5/2 ? ?(h11/2)2 and ph11/2 ? ?(h11/2)2 bands, thus indicating a magnetic rotation character for these bands. [ABSTRACT FROM AUTHOR]

Excited states in100Tc have been studied using the96Zr(7Li, 3n) reaction at a beam energy of 27 MeV. In the present work, evidence has been found for a second ?I= 1 band decaying via several stretched dipole transitions to the previously known ?I= 1 negative-parity band. Comparison of these data with those in neighbouring nuclei and also against recently reported criteria for chiral bands in nuclei, suggests that the two structures can be interpreted as chiral partners. Core quasi-particle coupling model calculations show reasonable agreement with the data and generally support the chiral interpretation of the states. [ABSTRACT FROM AUTHOR]

Abstract: High-spin states in 105Rh were populated by the 96Zr(13C, p3n) reaction at beam energies of 51 and 58 MeV, and studied using the EUROBALL IV γ-ray spectrometer and the DIAMANT charged particle array. A pair of nearly degenerate three-quasiparticle bands with the same spins and parity have been observed. Comparison of the experimental results with tilted axis cranking calculations confirms the chiral character of the two bands, while arguments based on the excitation of particles within the configuration of the yrast band and comparison with the previously observed γ band exclude the other possible interpretations. This is the first experimental evidence for three-quasiparticle chiral structure in the A ∼ 100 region, and the first simultaneous observation of a γ band and chiral partner bands in one nucleus. [Copyright &y& Elsevier]

The nucleus 106Rh was populated using the reaction 96Zr(13C, p2n) at a beam energy of 51 MeV. γ-ray transitions were identified using the EUROBALL-IV γ-ray spectrometer and the DIAMANT charged particle array. The yrast band, which is based upon a πg9/2-1⊗νh11/2 configuration, has been extended to Iπ=(22-). A new ΔI=1 band has been identified which resides ∼300 keV above the yrast band. Core–quasiparticle coupling model calculations show reasonably good agreement with the data. The properties of the two pairs of strongly coupled bands are consistent with a chiral interpretation for these states. [Copyright &y& Elsevier]

Abstract: The nuclides 168–170Pt were produced by bombarding isotopically enriched 92,94Mo targets with 336, 348MeV 78Kr ions. Prompt rays were detected at the target position and provided a selection criterion for the 168–170Pt nuclei. This technique enables the problem of the background from higher-energy decays in the spectrum to be circumvented. The Pt nuclei were separated in flight using the gas-filled separator RITU and implanted into the GREAT spectrometer, which was used to study subsequent decays. The -decay branching ratios of 164–166Os were deduced from the fraction of selected 168–170Pt nuclei correlated with decays of 164–166Os. The resulting branching ratios agree with the literature values but can have improved precision. [Copyright &y& Elsevier]

A new ab initio pair potential for water was generated by fitting 2510 interaction energies computed by the use of symmetry-adapted perturbation theory (SAPT). The new site-site functional form, named SAPT-5s, is simple enough to be applied in molecular simulations of condensed phases and at the same time reproduces the computed points with accuracy exceeding that of the elaborate SAPT-pp functional form used earlier [J. Chem. Phys. 107, 4207 (1997)]. SAPT-5s has been shown to quantitatively predict the water dimer spectra, see the following paper (paper II). It also gives the second virial coefficient in excellent agreement with experiment. Features of the water dimer potential energy surface have been analyzed using SAPT-5s. Average values of powers of the intermolecular separation--obtained from the ground-state rovibrational wave function computed in the SAPT-5s potential--have been combined with measured values to obtain a new empirical estimate of the equilibrium O-O separation equal to 5.50±0.01 bohr, significantly shorter than the previously accepted value. The residual errors in the SAPT-5s potential have been estimated by comparison to recent large-scale extrapolated ab initio calculations for water dimer. This estimate--together with the dissociation energy D[sub 0] computed from SAPT-5s--leads to a new prediction of the limit value of D[sub 0] equal to 1165±54 cm[sup -1], close to but significantly more accurate than the best empirical value. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]