Effect of crystal field on the magnetization of dilute hcp alloys

Journal ArticleMagnetization measurements on very dilute single-crystal alloys of Mg-Mn, Zn-Mn, and Zn-Cr in the temperature range of 2-0.008 K show that the ground state of these systems is determined by fine-structure splitting. For Mg-Mn the fine-structure constant D is +0.006 K with an effective spin of f while for Zn-Mn D is -0.07 K and for Zn-Cr it is 4-0.08 K for an effective spin of 1 in both cases. Over our temperature range there is no evidence for a Kondo spin-compensated state. For all impurity concentrations, even the 1 ppm level, Ruder man-Kittel-Kasuya-Yosida interactions play an important role as determined from magnetization measurements of polycrystalline Zn-Mn alloys

Application of SQUID magnetometer to nuclear magnetic thermometry

Journal ArticleThis paper presents an application of a SQUID magnetometer for low temperature thermometry using the magnetic properties of a nuclear paramagnet. The static magnetization of a material which obeys Curie's law provides a very sensitive means of thermometry. Also included in the device is the capability to observe, also with a SQUID magnetometer, the nuclear spin-lattice relaxation time TJ using NMR methods. This allows a temperature self-calibration of the thermometer system. As an example of a suitable nuclear paramagnet, magnetization and relaxation time data are presented for aluminum

Magnetic anisotropy of Zn-Cr alloys at very low temperatures

Journal ArticleThe temperature dependent magnetization of Zn-Cr single crystals was measured from 2K down to 10 mK using a SQUID magnetometer. A large anisotropy is observed for the magnetization along the parallel and perpendicular axes of the crystal. For low concentrations impurity-impurity reactions do not dominate the behavior of the system, although they are still present even in the 10 ppm impurity concentration range. The anisotropy in the magnetization, Mn-Mj, is negative which is in contrast with the Mn in Zn system where the anisotropy is positive. The results are analyzed in terms of crystal field splittings and exchange. These results have important implications for the Kondo effect in this system

Parental depressive symptoms, children’s emotional and behavioural problems, and parents’ expressed emotion - critical and positive comments

This is the final version of the article. Available from Public Library of Science via the DOI in this record.This longitudinal study examined whether mothers’ and fathers’ depressive symptoms predict, independently and interactively, children’s emotional and behavioural problems. It also examined bi-directional associations between parents’ expressed emotion constituents (parents’ child-directed positive and critical comments) and children’s emotional and behavioural problems. At time 1, the sample consisted of 160 families in which 50 mothers and 40 fathers had depression according to the Structured Clinical Interview for DSM-IV. Children’s mean age at Time 1 was 3.9 years (SD = 0.8). Families (n = 106) were followed up approximately 16 months later (Time 2). Expressed emotion constituents were assessed using the Preschool Five Minute Speech Sample. In total, 144 mothers and 158 fathers at Time 1 and 93 mothers and 105 fathers at Time 2 provided speech samples. Fathers’ depressive symptoms were concurrently associated with more child emotional problems when mothers had higher levels of depressive symptoms. When controlling for important confounders (children’s gender, baseline problems, mothers’ depressive symptoms and parents’ education and age), fathers’ depressive symptoms independently predicted higher levels of emotional and behavioural problems in their children over time. There was limited evidence for a bi-directional relationship between fathers’ positive comments and change in children’s behavioural problems over time. Unexpectedly, there were no bi-directional associations between parents’ critical comments and children’s outcomes. We conclude that the study provides evidence to support a whole family approach to prevention and intervention strategies for children’s mental health and parental depression

Stochastic effects at ripple formation processes in anisotropic systems with multiplicative noise

We study pattern formation processes in anisotropic system governed by the Kuramoto-Sivashinsky equation with multiplicative noise as a generalization of the Bradley-Harper model for ripple formation induced by ion bombardment. For both linear and nonlinear systems we study noise induced effects at ripple formation and discuss scaling behavior of the surface growth and roughness characteristics. It was found that the secondary parameters of the ion beam (beam profile and variations of an incidence angle) can crucially change the topology of patterns and the corresponding dynamics

Working memory updating training reduces state repetitive negative thinking: proof-of-concept for a novel cognitive control training (article)

This is the final version. Available on open access from Elsevier via the DOI in this record.The research data supporting this publication are openly available from the University of Exeter's institutional repository at https://doi.org/10.24378/exe.3283Repetitive negative thinking (RNT) is a proximal risk factor implicated in the onset and maintenance of common mental health problems such as depression and anxiety. Adolescence may be a key developmental window in which to target RNT and prevent the emergence of such disorders. Impairments in updating the contents of working memory are hypothesised to causally contribute to RNT, and some theorists have suggested these difficulties may be specific to the manipulation of negative information. The present study compared the effects of computerised adaptive working memory updating training (in which the task becomes more difficult as performance improves) to a non-adaptive control task in reducing levels of RNT. 124 healthy young people were randomised to 20 sessions of (i) working memory updating training using neutral stimuli, (ii) working memory updating training using negative stimuli, or (iii) non-adaptive working memory updating training. Adaptive working memory updating training using neutral, but not negative, stimuli resulted in significant improvements to working memory updating for negative material, as assessed using an unpractised task, and significant reductions in susceptibility to state RNT. These findings demonstrate proof-of-concept that working memory updating training has the potential to reduce susceptibility to episodes of state RNT.Wellcome Trus

Negative affect and ruminative self-focus during everyday goal pursuit

Models of self-regulation propose that negative affect is generated when progress towards goals is perceived to be inadequate. Similarly, ruminative thinking is hypothesised to be triggered by unattained goals (Martin & Tesser, 1996). We conducted an experience-sampling study in which participants recorded their negative affect, ruminative self-focus, and goal appraisals eight times daily for one week. Negative affect and ruminative self-focus were each associated with low levels of goal success and (with the exception of sadness) high levels of goal importance. As predicted, the combination of low goal success and high goal importance was associated with the highest levels of negative affect, and this interaction was marginally significant for ruminative self-focus. Decomposition of the ruminative self-focus measure revealed that the success by importance interaction was significantly associated with focus on problems but not focus on feelings. Findings did not differ for individuals reporting high versus low levels of depressive symptoms or trait rumination. These results suggest that self-regulatory models of goal pursuit provide a useful explanatory framework for the study of affect and ruminative thinking in everyday life

Christian Higher Education in Europe: A Historical Overview

The history of Christian higher education in Europe may be analyzed in terms of seven eras. From their medieval origins in scholasticism and the practical needs of students and rulers, universities passed through Renaissance humanism to a period of decay, yet remained substantially Christian in intent. The Enlightenment exercised a partially secularizing influence, and the neohumanist reaction against it also tended to dilute the faith. The recent era of the late 20th and early 21st centuries has been associated with the rise of postmodernism and the involvement of the state in the quest for relevance. A Christian response to contemporary circumstances is to engage with the cultural currents of the present day and, in drawing on the thought of John Henry Newman and Sir Walter Moberly, to ensure the integration of Christianity into higher education so that discussion of ultimate questions is informed by the Christian faith

Quantity, composition, and source of sediment collected in sediment traps along the fringing coral reef off Molokai, Hawaii

This paper is not subject to U.S. copyright. The definitive version was published in Marine Pollution Bulletin 52 (2006): 1034-1047, doi:10.1016/j.marpolbul.2006.01.008.Sediment traps were used to evaluate the frequency, cause, and relative intensity of sediment mobility/resuspension along the fringing coral reef off southern Molokai (February 2000–May 2002). Two storms with high rainfall, floods, and exceptionally high waves resulted in sediment collection rates > 1000 times higher than during non-storm periods, primarily because of sediment resuspension by waves. Based on quantity and composition of trapped sediment, floods recharged the reef flat with land-derived sediment, but had a low potential for burying coral on the fore reef when accompanied by high waves. The trapped sediments have low concentrations of anthropogenic metals. The magnetic properties of trapped sediment may provide information about the sources of land-derived sediment reaching the fore reef. The high trapping rate and low sediment cover indicate that coral surfaces on the fore reef are exposed to transient resuspended sediment, and that the traps do not measure net sediment accumulation on the reef surface

Aerobic and anaerobic metabolism during activity in the lizard Dipsosaurus dorsalis

1. Oxygen consumption and lactate content of the lizard Dipsosaurus dorsalis were determined under standard conditions and for a bout of maximal activity induced by a 2-min period of electrical stimulation. Observations were made between 25 ° and 45 °C.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47109/1/359_2004_Article_BF00693633.pd