129 research outputs found
Local yield stress statistics in model amorphous solids
We develop and extend a method presented in [S. Patinet, D. Vandembroucq, and
M. L. Falk, Phys. Rev. Lett., 117, 045501 (2016)] to compute the local yield
stresses at the atomic scale in model two-dimensional Lennard-Jones glasses
produced via differing quench protocols. This technique allows us to sample the
plastic rearrangements in a non-perturbative manner for different loading
directions on a well-controlled length scale. Plastic activity upon shearing
correlates strongly with the locations of low yield stresses in the quenched
states. This correlation is higher in more structurally relaxed systems. The
distribution of local yield stresses is also shown to strongly depend on the
quench protocol: the more relaxed the glass, the higher the local plastic
thresholds. Analysis of the magnitude of local plastic relaxations reveals that
stress drops follow exponential distributions, justifying the hypothesis of an
average characteristic amplitude often conjectured in mesoscopic or continuum
models. The amplitude of the local plastic rearrangements increases on average
with the yield stress, regardless of the system preparation. The local yield
stress varies with the shear orientation tested and strongly correlates with
the plastic rearrangement locations when the system is sheared correspondingly.
It is thus argued that plastic rearrangements are the consequence of shear
transformation zones encoded in the glass structure that possess weak slip
planes along different orientations. Finally, we justify the length scale
employed in this work and extract the yield threshold statistics as a function
of the size of the probing zones. This method makes it possible to derive
physically grounded models of plasticity for amorphous materials by directly
revealing the relevant details of the shear transformation zones that mediate
this process
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The inner world of shyness : an exploration of object relations in shy college students.
The relationship between object relations (the internal basis for the capacity to relate) and shyness in college students was studied. In part one, 150 male and female subjects were administered the Social Reticence Scale (SRS), the Revised Cheek and Buss Shyness Scale (RCBS) and the Bell Object Relations Reality Testing Inventory (BORRTI). The association between scores on the shyness measures and scores on the subscales of the BORRTI were examined. The mean scores of 32 shy subjects and 55 not-shy subjects were compared on these same BORRTI subscales. Scores on the two shyness measures were significantly and positively correlated with the BORRTI dimensions Alienation, Insecure Attachment, and Social Incompetence, but were unrelated to Egocentricity. Significant differences on these same three dimensions were also found between shy and not-shy subjects. Although not predicted, scores on the shyness measures were found to be significantly and positively associated with the reality testing dimension Uncertainty of Perception. The mean scores of shy and not-shy subjects were significantly different on this dimension. In part two, 20 shy subjects were administered the Thematic Apperception Test (TAT) and interviewed using the Object Relations Interview from an Interview Guide for the Clinical Assessment of Ego Functions. These subjects were asked about early relationships and about the experience of shyness. Interview and TAT themes were presented in terms of their relationships to the quantitative findings. Overall, the quantitative and qualitative findings suggest that shy individuals have significantly greater difficulty with object relations functioning than not-shy individuals and that shy people experience a great deal of anxiety and pain in relationships. These findings were discussed in relation to object relations theories of narcissism, object constancy, and schizoid and borderline dynamics. These data point to the need for consideration of unconscious dynamics in shyness and the usefulness of further research on object relations in shy people
Rare Gene Copy Number Variations Are Associated with Specific Endophenotypes in Schizophrenia
Impact of natural disasters on income inequality in Sri Lanka
We explore the relationship between natural disasters and income inequality in Sri Lanka as the first study of this nature for the country. The analysis uses a unique panel data set constructed for the purpose of this paper. It contains district inequality measures based on household income reported in six waves of the Household Income and Expenditure Survey of Sri Lanka during the period between 1990 and 2013, data on disaster affected population and other economic and social indicators. Employing a panel fixed effects estimator, we find that contemporaneous natural disasters and their immediate lags significantly and substantially decrease inequality in per adult equivalent household income as measured by the Theil index. Findings are robust across various inequality metrics, sub-samples and alternative estimators such as Ordinary Least Squares and System GMM. However, natural disasters do not affect household expenditure inequality. Either households behave as if they have a permanent income or all households reduce their expenditure proportionately irrespective of their income level in responding to natural disasters. Natural disasters decrease non-seasonal agricultural and non-agricultural income inequality but increase seasonal agricultural income inequality. Income of richer households is mainly derived from non-agricultural sources such as manufacturing and business activities and non-seasonal agricultural activities. Poorer households have a higher share of agricultural income
The ends justifies the means: A global research agenda for political marketing and public affairs
This is the peer reviewed version of the following article: Harris, P., & Sun, H. (2017). The ends justify the means: A global research agenda for political marketing and public affairs. Journal of Public Affairs, 14(4), e1693 which has been published in final form at http://dx.doi.org/10.1002/pa.1693 This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Political marketing has developed into an increasingly mainstream discipline in universities globally over the last decade. There are many schools of political marketing with different approaches, such as the North American approach, the Western and Eastern European perspectives, and the Asian position. The study and application of political marketing has been categorised with different perspectives, such as electoral, governmental, and international aspects. It is becoming increasingly evident that political marketing needs further classification like any matured and established discipline. A close analysis of political marketing practices and academic research leads one to perceive two distinct areas of political exchanges in two different markets: the intranational market and the international market
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