Derivative moments for characteristic polynomials from the CUE

We calculate joint moments of the characteristic polynomial of a random unitary matrix from the circular unitary ensemble and its derivative in the case that the power in the moments is an odd positive integer. The calculations are carried out for finite matrix size and in the limit as the size of the matrices goes to infinity. The latter asymptotic calculation allows us to prove a long-standing conjecture from random matrix theory.Comment: 31 pages, 3 figure

Lithiated organophosphorus enamines : a new synthetic approach and the first crystal structures

Made by a nitrile insertion/hydrogen migration process via Ph2P(O)CH2Li and (BuCN)-C-t, the enamide Ph2P(O)CH=C(Bu-t)N(H)Li and its TMEDA hemisolvate exist as tetrameric and dinuclear arrangements respectively: the novel structure of the starting lithiated phosphane oxide, also in its TMEDA hemisolvated form, is shown to contain Li-C contacts of two distinct types

Dreading the boards: stress response to a competitive audition characterized by social-evaluative threat.

The capacity of psychosocial stressors to provoke the hypothalamic-pituitary-adrenal axis has been demonstrated to vary depending upon a number of psychological factors. Laboratory stressors characterized by social-evaluative threat are proposed to be the most efficacious in the elicitation of a cortisol stress response. Salivary cortisol, cardiovascular, and subjective responses of 16 healthy adults facing a naturalistic stressor characterized by social-evaluative threat (competitive performance auditions) were examined. Audition exposure was sufficient to provoke significant cortisol, arterial blood pressure (systolic and diastolic), and subjective stress responses. Cortisol response reactivity (area under the curve with respect to increase [AUCi]) also correlated with participants' subjective rating of social-evaluative threat. The competitive performance audition context is therefore considered a promising context in which to further explore cortisol responsivity to social-evaluative threat

Can nurses help identify patients with depression following stroke? A pilot study using two methods of detection

Aim. This paper reports a study to determine the accuracy of the Geriatric Mental State examination and the Montgomery-Asberg Depression Rating Scale, when administered by a nurse, in detecting depression in patients who have recently had a stroke. Background. After a stroke, survivors spend considerable amounts of time in the direct care of nurses. Many show signs of depression, and this has been associated with an adverse effect on recovery and rehabilitation. Identifying those with depression when they have communication and cognitive difficulties is especially difficult. Treatments are available to assist in the management of depression, and early detection and intervention may assist in this process. Method. A cross-sectional pilot study was conducted, comparing (a) clinical diagnosis of depression by a psychiatrist with (b) two clinical interviews, using the Geriatric Mental State examination and the Montgomery-Asberg Depression Rating Scale, conducted by a nurse. The data were collected in 2002. Findings. Twenty-eight patients, who were still in hospital in the second week poststroke, were included. The median age was 72 (interquartile range: 61-78). There were 14 males. The psychiatrist rated seven (25%) patients as depressed. The Geriatric Mental State examination had a sensitivity of 71%, a specificity of 67%, a positive predictive value of 42%, a negative predictive value of 88% in detecting depression and an overall efficiency of 68%. The Montgomery-Asberg Depression Rating Scale had a sensitivity of 100%, a specificity of 65%, a positive predictive value of 54%, a negative predictive value of 100% and an overall efficiency of 75%. Conclusion. In this study, the Geriatric Mental State examination and the Montgomery-Asberg Depression Rating Scale were at least as efficient at detecting the depression in patients who have had a stroke. However, as the Montgomery-Asberg Depression Rating Scale is quicker to administer, it may prove more useful to nurses clinically. © 2007 The Authors. Journal compilation 2007 Blackwell Publishing Ltd