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The article focuses on the changes in the attitude of women students during four years in college. No evaluation of educational outcomes is adequate without appraisal of attitudes and interests and other of the more subtle aspects of personality. Attitudes and interests are vital forces in life and in education. As such they are subject to enormous change and growth, depending upon the total environment and developmental history. Studies are appearing which trace attitude and interest changes in personality in the same students through their college years. These longitudinal studies are definitely superior to the cross-section studies if the purpose is to trace actual changes in individuals. The findings of various attitude studies are by no means conclusive or remarkable. Additional long-time investigations at the college level would appear desirable. Improvements in new studies might include the use of new measuring devices, covering wider areas of attitudes and tracing more specific and detailed changes.

We report angle resolved photoemission experiments on the electron doped Heisenberg antiferromagnet (Sr1-xLax)2IrO4. For a doping level of x=0.05, we find an unusual metallic state with coherent nodal excitations and an antinodal pseudogap bearing strong similarities with underdoped cuprates. This state emerges from a rapid collapse of the Mott gap with doping resulting in a large underlying Fermi surface that is backfolded by a (p,p) reciprocal lattice vector which we attribute to the intrinsic structural distortion of Sr2IrO4. [ABSTRACT FROM AUTHOR]

Nonresonant Raman spectroscopy in the hard x-ray regime has been used to explore the electronic structure of the first two members of the Ruddlesden-Popper series Srn+1IrnO3n+1 of iridates. By tuning the photon energy transfer around 530 eV, we have been able to explore the oxygen K-near-edge structure with bulk sensitivity. The angular dependence of the spectra has been exploited to assign features in the 528-535 eV energy range to specific transitions involving the Ir 5d orbitals. This has allowed us to extract reliable values for both the t2g-eg splitting arising from the cubic component of the crystal field (10Dq), in addition to the splitting of the eg orbitals due to tetragonal distortions. The values we obtain are (3.8, 1.6) eV and (3.55, 1.9) eV for Sr2IrO4and Sr3lr2O7, respectively. [ABSTRACT FROM AUTHOR]

Resonant inelastic x-ray scattering (RIXS) experiments performed at the oxygen K edge on the iridate perovskites Sr2 IrO4 and Sr3 Ir2 O7 reveal a sequence of well-defined dispersive modes over the energy range up to ~0.8 eV . The momentum dependence of these modes and their variation with the experimental geometry allows us to assign each of them to specific collective magnetic and/or electronic excitation processes, including single and bimagnons, and spin-orbit and electron-hole excitons. We thus demonstrate that dispersive magnetic and electronic excitations are observable at the O K edge in the presence of the strong spin-orbit coupling in the 5 d shell of iridium and strong hybridization between Ir 5 d and O 2 p orbitals, which confirm and expand theoretical expectations. More generally, our results establish the utility of O K-edge RIXS for studying the collective excitations in a range of 5 d materials that are attracting increasing attention due to their novel magnetic and electronic properties. Especially, the strong RIXS response at O K edge opens up the opportunity for investigating collective excitations in thin films and heterostructures fabricated from these materials. [ABSTRACT FROM AUTHOR]

High-pressure x-ray absorption spectroscopy was performed at the Ir L 3 and L 2 absorption edges of Sr 3 Ir 2 O 7 . The branching ratio of white-line intensities continuously decreases with pressure, reflecting a reduction in the angular part of the expectation value of the spin-orbit coupling operator, ( L . S ) . Up to the high-pressure structural transition at 53 GPa, this behavior can be explained within a single-ion model, where pressure increases the strength of the cubic crystal field, which suppresses the spin-orbit induced hybridization of Jeff = 3 / 2 and e g levels. We observe a further reduction of the branching ratio above the structural transition, which cannot be explained within a single-ion model of spin-orbit coupling and cubic crystal fields. This change in ( L . S ) in the high-pressure, metallic phase of Sr 3 Ir 2 O 7 could arise from noncubic crystal fields or a bandwidth-driven hybridization of Jeff = 1 / 2 , 3 / 2 states and suggests that the electronic ground state significantly deviates from the Jeff = 1 / 2 limit. [ABSTRACT FROM AUTHOR]

The collective magnetic excitations in the spin-orbit Mott insulator (Sr1-xLax)2 IrO4 (x = 0, 0.01, 0.04, 0.1) were investigated by means of resonant inelastic x-ray scattering. We report significant magnon energy gaps at both the crystallographic and antiferromagnetic zone centers at all doping levels, along with a remarkably pronounced momentum-dependent lifetime broadening. The spin-wave gap is accounted for by a significant anisotropy in the interactions between Jeff = 1/2 isospins, thus marking the departure of Sr2IrO4 from the essentially isotropic Heisenberg model appropriate for the superconducting cuprates. [ABSTRACT FROM AUTHOR]

We study the structural evolution of Sr3Ir2O7 as a function of pressure using x-ray diffraction. At a pressure of 54 GPa at room temperature, we observe a first-order structural phase transition, associated with a change from tetragonal to monoclinic symmetry and accompanied by a 4% volume collapse. Rietveld refinement of the high-pressure phase reveals a novel modification of the Ruddlesden-Popper structure, which adopts an altered stacking sequence of the perovskite bilayers. As the positions of the oxygen atoms could not be reliably refined from the data, we use density functional theory (local-density approximation+U+spin orbit) to optimize the crystal structure and to elucidate the electronic and magnetic properties of Sr3Ir2O7 at high pressure. In the low-pressure tetragonal phase, we find that the in-plane rotation of the IrO6 octahedra increases with pressure. The calculations further indicate that a bandwidth-driven insulator-metal transition occurs at ~20 GPa, along with a quenching of the magnetic moment. In the high-pressure monoclinic phase, structural optimization resulted in complex tilting and rotation of the oxygen octahedra and strongly overlapping t2g and eg bands. The t2g bandwidth renders both the spin-orbit coupling and electronic correlations ineffectual in opening an electronic gap, resulting in a robust metallic state for the high-pressure phase of Sr3Ir2O7. [ABSTRACT FROM AUTHOR]

The magnetic critical scattering in Sr2IrO4 has been characterized using x-ray resonant magnetic scattering (XRMS) both below and above the three-dimensional antiferromagnetic ordering temperature TN. The order parameter critical exponent below TN is found to be β=0.195(4), in the range of the two-dimensional (2D) XYh4 universality class. Over an extended temperature range above TN, the amplitude and correlation length of the intrinsic critical fluctuations are well described by the 2D Heisenberg model with XY anisotropy. This contrasts with an earlier study of the critical scattering over a more limited range of temperature, which found agreement with the theory of the isotropic 2D Heisenberg quantum antiferromagnet, developed to describe the critical fluctuations of the conventional Mott insulator La2CuO4 and related systems. Our study therefore establishes the importance of XY anisotropy in the low-energy effective Hamiltonian of Sr2IrO4, the prototypical spin-orbit Mott insulator. [ABSTRACT FROM AUTHOR]

The magnetic excitation spectrum in the bilayer iridate Sr3Ir2O7 has been investigated using high-resolution resonant inelastic x-ray scattering (RIXS) performed at the iridium L3 edge and theoretical techniques. A study of the systematic dependence of the RIXS spectrum on the orientation of the wave-vector transfer Q, with respect to the iridium-oxide bilayer, has revealed that the magnon dispersion is comprised of two branches well separated in energy and gapped across the entire Brillouin zone. Our results contrast with those of an earlier study which reported the existence of a single dominant branch. While these earlier results were interpreted as two overlapping modes within a spin-wave model of weakly coupled iridium-oxide planes, our results are more reminiscent of those expected for a system of weakly coupled dimers. In this latter approach, the lower- and higher-energy modes find a natural explanation as those corresponding to transverse and longitudinal fluctuations, respectively. We have therefore developed a bond-operator theory which describes the magnetic dispersion in Sr3Ir2O7 in terms of quantum dimer excitations. In our model, dimerization is produced by the leading Heisenberg exchange Jc, which couples iridium ions in adjacent planes of the bilayer. The Hamiltonian also includes in-plane exchange J, as well as further neighbor couplings and relevant anisotropies. The bond-operator theory provides an excellent account of the dispersion of both modes, while the measured Q dependence of the RIXS intensities is in reasonable qualitative accord with the spin-spin correlation function calculated from the theory. We discuss our results in the context of the quantum criticality of bilayer dimer systems in the presence of anisotropic interactions derived from strong spin-orbit coupling. [ABSTRACT FROM AUTHOR]

The hyperkagome antiferromagnet Na4Ir3O8 represents the first genuine candidate for the realization of a three-dimensional quantum spin liquid. It can also be doped towards a metallic state, thus offering a rare opportunity to explore the nature of the metal-insulator transition in correlated, frustrated magnets. Here, we report thermodynamic and transport measurements in both metallic and weakly insulating single crystals down to 150 mK. While in the metallic sample the phonon thermal conductivity (ph) is almost in the boundary scattering regime, in the insulating sample, we find a large reduction ph over a very wide temperature range. This result can be ascribed to the scattering of phonons off the gapless magnetic excitations that are seen in the low-temperature specific heat. This works highlights the peculiarity of the metal-insulator transition in Na3+xIr3O8 and demonstrates the importance of the coupling between lattice and spin degrees of freedom in the presence of strong spin-orbit coupling. [ABSTRACT FROM AUTHOR]

Depersonalisation (DP) and derealisation (DR) are subjective experiences of unreality in, respectively, one's sense of self and the outside world. These experiences occur on a continuum from transient episodes that are frequently reported in healthy individuals under certain situational conditions to a chronic psychiatric disorder that causes considerable distress (depersonalisation disorder, DPD). Despite the relatively high rates of reporting these symptoms, little research has been conducted into psychological treatments for this disorder. We suggest that there is compelling evidence to link DPD with the anxiety disorders, particularly panic. This paper proposes that it is the catastrophic appraisal of the normally transient symptoms of DP/DR that results in the development of a chronic disorder. We suggest that if DP/DR symptoms are misinterpreted as indicative of severe mental illness or brain dysfunction, a vicious cycle of increasing anxiety and consequently increased DP/DR symptoms will result. Moreover, cognitive and behavioural responses to symptoms such as specific avoidances, 'safety behaviours' and cognitive biases serve to maintain the disorder by increasing awareness of the symptoms, heightening the perceived threat and preventing disconfirmation of the catastrophic misinterpretations. A coherent model facilitates the development of potentially effective cognitive and behavioural interventions.