Relational and physical aggression in late childhood : links to social adjustment in group and dyadic relations

Relational aggression (RA), thought to be more typical of females, is a form of aggression in which relationships are used as vehicles of harm (Crick & Grotpeter, 1995). This study investigated sex-differences in the prevalence of RA and physical aggression (PA), as well as the group and friendship relations of relationally and physically aggressive children. It was predicted that (a) girls would be rated as more relationally aggressive than boys when extreme group scores of RA were examined; (b) boys would be rated as more relationally aggressive than girls when continuous measures of RA were used; (c) boys would be higher than girls in PA regardless of the assessment measure; and (d) girls would use more RA than PA, whereas boys would use more PA than RA. It was also predicted that (e) relationally aggressive boys and physically aggressive girls would be at heightened risk for peer rejection; (f) aggressive children would have mutual friendships in spite of their lack of popularity; (g) relationally and physically aggressive children would have similarly aggressive friends; and (h) RA and PA would predict lower-quality friendships

Approaching rejection sensitivity from a multidimensional perspective : predicting romantic maladjustment, targets of romantic attraction and depression in middle adolescence

The associations between rejection sensitivity and romantic maladjustment were examined along three lines of inquiry. The first addressed whether the various dimensions of rejection sensitivity (i.e., reactive anxiety, reactive anger, and harboring the expectation of rejection) were differentially associated with the use of physical coercion, verbal/emotional coercion, and compliance in romantic relationships. The second examined whether patterns of assortative romantic attraction were present among rejection-sensitive and other at-risk youth. Finally, the third line of inquiry explored whether the associations between rejection sensitivity and depression were mediated by adolescents' involvement in maladjusted romantic relationships. Three hundred and thirty-two senior high school students (188 girls, mean age = 16.7 years) completed questionnaires assessing (a) attachment style with parents and peers, (b) rejection sensitivity with parents and peers, (c) the use of coercion and compliance in romantic relationships, (d) targets of romantic attraction, and (e) depression. Results indicated that, above and beyond the effects of attachment, angry rejection sensitivity with peers positively predicted the use of physical and verbal/emotional coercion in romantic relationships. On the contrary, anxious rejection sensitivity with peers was found to negatively predict the use of physical and verbal/emotional coercion in romance. The use of compliance in romantic relationships was not associated with rejection sensitivity with either parents or peers. In examining the second series of questions, results revealed that adolescents who expected rejection within the peer domain were increasingly attracted to others who shared similar rejection concerns. Moreover, boys who employed physical coercion in romance were increasingly attracted to girls who employed physical as well as verbal/emotional coercion in romantic relationships. Girls, however, regardless of their own level of maladjustment, did not show a preference for maladjusted boys. Finally, regarding the third line of inquiry, results indicated that the associations between rejection sensitivity and depression were partially mediated by adolescents' involvement in maladjusted romantic relationships. Findings support approaching the construct of rejection sensitivity from a multidimensional perspective to fruitfully predict romantic maladjustment, assortative patterns of romantic attraction among at-risk youth, and the increased likelihood of depressive outcomes in middle adolescence. Results are discussed in terms of a unifying model of socialization across development

Mammalian behavior and physiology converge to confirm sharper cochlear tuning in humans

Frequency analysis of sound by the cochlea is the most fundamental property of the auditory system. Despite its importance, the resolution of this frequency analysis in humans remains controversial. The controversy persists because the methods used to estimate tuning in humans are indirect and have not all been independently validated in other species. Some data suggest that human cochlear tuning is considerably sharper than that of laboratory animals, while others suggest little or no difference between species. We show here in a single species (ferret) that behavioral estimates of tuning bandwidths obtained using perceptual masking methods, and objective estimates obtained using otoacoustic emissions, both also employed in humans, agree closely with direct physiological measurements from single auditory-nerve fibers. Combined with human behavioral data, this outcome indicates that the frequency analysis performed by the human cochlea is of significantly higher resolution than found in common laboratory animals. This finding raises important questions about the evolutionary origins of human cochlear tuning, its role in the emergence of speech communication, and the mechanisms underlying our ability to separate and process natural sounds in complex acoustic environments

Profile of the U 5f magnetization in U/Fe multilayers

Recent calculations, concerning the magnetism of uranium in the U/Fe multilayer system have described the spatial dependence of the 5f polarization that might be expected. We have used the x-ray resonant magnetic reflectivity technique to obtain the profile of the induced uranium magnetic moment for selected U/Fe multilayer samples. This study extends the use of x-ray magnetic scattering for induced moment systems to the 5f actinide metals. The spatial dependence of the U magnetization shows that the predominant fraction of the polarization is present at the interfacial boundaries, decaying rapidly towards the center of the uranium layer, in good agreement with predictions.Comment: 7 pages, 6 figure

Resonant X-Ray Magnetic Scattering from CoO

We analyze the recent experiment [W. Neubeck {\em et al.}, Phys. Rev. B \vol(60,1999,R9912)] for the resonant x-ray magnetic scattering (RXMS) around the K edge of Co in the antiferromagnet CoO. We propose a mechanism of the RXMS to make the $4p$ states couple to the magnetic order: the intraatomic exchange interaction between the $4p$ and the $3d$ states and the $p$-$d$ mixing to the $3d$ states of neighboring Co atoms. These couplings induce the orbital moment in the $4p$ states and make the scattering tensor antisymmetric. Using a cluster model, we demonstrate that this modification gives rise to a large RXMS intensity in the dipole process, in good agreement with the experiment. We also find that the pre-edge peak is generated by the transition to the $3d$ states in the quadrupole process, with negligible contribution of the dipole process. We also discuss the azimuthal angle dependence of the intensity.Comment: 15 pages, 8 figure

Circularly polarised X-rays as a probe of non-collinear magnetic order in multiferroic TbMnO3

Non-resonant X-ray magnetic scattering has been used to study the magnetic structure of multiferroic TbMnO3 in its ferroelectric phase. Circularly polarized X-rays were combined with a full polarization analysis of the scattered beam to reveal important new information on the magnetic structure of this canonical multiferroic. An applied electric field is shown to create a magnetic nearly mono-domain state in which the cylcoidal order on the Mn sublattice rotates either clockwise or counter-clockwise depending on the sign of the field. It is demonstrated how this technique provides sensitivity to the absolute sense of rotation of the Mn moments, and to components of the ordering on the Tb sublattice and phase shifts that earlier neutron diffraction experiments could not resolve.Comment: 4 pages, 3 figure

Femtoscale magnetically induced lattice distortions in multiferroic TbMnO3

Magneto-electric multiferroics exemplified by TbMnO3 possess both magnetic and ferroelectric long-range order. The magnetic order is mostly understood, whereas the nature of the ferroelectricity has remained more elusive. Competing models proposed to explain the ferroelectricity are associated respectively with charge transfer and ionic displacements. Exploiting the magneto-electric coupling, we use an electric field to produce a single magnetic domain state, and a magnetic field to induce ionic displacements. Under these conditions, interference charge-magnetic X-ray scattering arises, encoding the amplitude and phase of the displacements. When combined with a theoretical analysis, our data allow us to resolve the ionic displacements at the femtoscale, and show that such displacements make a significant contribution to the zero-field ferroelectric moment.Comment: This is the author's version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in Science VOL 333, (2011), doi:10.1126/science.120808