Nanoscale spin reversal by non-local angular momentum transfer following ultrafast laser excitation in ferrimagnetic GdFeCo.

Ultrafast laser techniques have revealed extraordinary spin dynamics in magnetic materials that equilibrium descriptions of magnetism cannot explain. Particularly important for future applications is understanding non-equilibrium spin dynamics following laser excitation on the nanoscale, yet the limited spatial resolution of optical laser techniques has impeded such nanoscale studies. Here we present ultrafast diffraction experiments with an X-ray laser that probes the nanoscale spin dynamics following optical laser excitation in the ferrimagnetic alloy GdFeCo, which exhibits macroscopic all-optical switching. Our study reveals that GdFeCo displays nanoscale chemical and magnetic inhomogeneities that affect the spin dynamics. In particular, we observe Gd spin reversal in Gd-rich nanoregions within the first picosecond driven by the non-local transfer of angular momentum from larger adjacent Fe-rich nanoregions. These results suggest that a magnetic material's microstructure can be engineered to control transient laser-excited spins, potentially allowing faster (~ 1 ps) spin reversal than in present technologies.

Stroke volume equation for impedance cardiography.

The study's goal was to determine if cardiac output (CO), obtained by impedance cardiography (ICG), would be improved by a new equation N, implementing a square root transformation for dZ/dtmax/Z0, and a variable magnitude, mass-based volume conductor Vc. Pulmonary artery catheterisation was performed on 106 cardiac surgery patients pre-operatively. Post-operatively, thermodilution cardiac output (TDCO) was simultaneously compared with ICG CO. dZ/dtmax/Z0 and Z0 were obtained from a proprietary bioimpedance device. The impedance variables, in addition to left ventricular ejection time TLVE and patient height and weight, were input using four stroke volume (SV) equations: Kubicek (K), Sramek (S), Sramek-Bernstein (SB), and a new equation N. CO was calculated as SV x heart rate. Data are presented as mean +/- SD. One way repeated measures of ANOVA followed by the Tukey test were used for inter-group comparisons. Bland-Altman methods were used to assess bias, precision and limits of agreement. P< 0.05 was considered statistically significant. CO implementing N (6.06 +/- 1.48 l min(-1)) was not different from TDCO (5.97 +/- 1.41 l min(-1)). By contrast, CO calculated using K (3.70 +/- 1.53 l min(-1)), S (4.16 +/- 1.83 l min(-1)) and SB (4.37 +/- 1.82 l min(-1)) was significantly less than TDCO. Bland-Altman analysis showed poor agreement between TDCO and K, S and SB, but not between TDCO and N. Compared with TDCO, equation N, using a square-root transformation for dZ/dtmax/Z0, and a mass-based Vc, was superior to existing transthoracic impedance techniques for SV and CO determination.

Local jamming via penetration of a granular medium.

We present a series of measurements examining the penetration force required to push a flat plate vertically through a dense granular medium, focusing in particular on the effects of the bottom boundary of the vessel containing the medium. Our data demonstrate that the penetration force near the bottom is strongly affected by the surface properties of the bottom boundary, even many grain diameters above the bottom. Furthermore, the data indicate an intrinsic length scale for the interaction of the penetrating plate with the vessel bottom via the medium. This length scale, which corresponds to the extent of local jamming induced by the penetrating plate, has a square root dependence both upon the plate radius and the ambient granular stress near the bottom boundary, but it is independent of penetration velocity and grain diameter.

Gender differences in the prediction of problem alcohol use in adulthood: exploring the influence of family factors and childhood maltreatment.

OBJECTIVE: The purpose of this study was to contrast men and women in prospective relationships among family-oriented and alcohol-related variables obtained during adolescence, childhood physical, emotional and sexual abuse collected retrospectively, and later adult problem alcohol use. METHOD: In structural equation models, early family processes (support/bonding, parent drug-use problems, parental divorce and childhood maltreatment) and prior alcohol use simultaneously predicted adult problem alcohol use at two later time points in a longitudinal community sample of 426 (305 female) adults. RESULTS: Significant relationships were found among family processes, childhood maltreatment, and problem alcohol use within time and longitudinally for both men and women. Greater family support/bonding during adolescence predicted less problem alcohol use in adulthood. Men and women who experienced sexual abuse as a child reported more problem alcohol use in adulthood. Problem alcohol use was stable across time. Men reported more problem alcohol use in adolescence and adulthood, and women reported more early sexual abuse. These results contradict those that find no significant relationships between childhood abuse and subsequent alcohol-related problems. Parental drug use problems during the participant's adolescence did not directly predict problem alcohol use in adulthood. The relationship was more indirect in that parental drug use was associated with family-related concomitants that in turn were significant predictors of more problem alcohol use in adulthood. CONCLUSIONS: The strong stability for problem alcohol use across the three time periods is a signal that alcohol use in adolescence should not be ignored; furthermore, family dynamics need attention in addressing problem alcohol use.

Associations between four types of childhood neglect and personality disorder symptoms during adolescence and early adulthood: findings of a community-based longitudinal study.

Data from a community-based longitudinal study were used to investigate the association between childhood neglect and personality disorder (PD) symptom levels during adolescence and early adulthood. Psychosocial and psychiatric interviews were administered to a representative sample of 738 youths and their mothers from upstate New York in 1975, 1983, 1985-1986, and 1991-1993. Evidence of childhood cognitive, emotional, physical, and supervision neglect was obtained from the maternal interviews that were conducted in 1975, 1983, and 1985-1986, and from New York State records. PDs were assessed among the youths in 1985-1986, when they were adolescents, and in 1991-1993, when they were young adults. Findings indicated that childhood emotional, physical, and supervision neglect were associated with increased risk for PDs and with elevated PD symptom levels during adolescence and early adulthood, after age, sex, childhood physical or sexual abuse, other types of childhood neglect, and cooccurring PD symptoms were controlled statistically. Childhood emotional neglect was associated with increased risk for avoidant PD and with paranoid and Cluster A PD symptom levels during adolescence and early adulthood. Childhood physical neglect was associated with increased risk for schizotypal PD and with Cluster A PD symptom levels during adolescence and early adulthood. Childhood supervision neglect was associated with increased risk for passive-aggressive and Cluster B PDs and with borderline, paranoid, and passive-aggressive PD symptom levels during adolescence and early adulthood. The present findings suggest that childhood emotional, physical, and supervision neglect may play a role in the etiology of some PDs.

A latent variable analysis of coexisting emotional deficits in substance abusers: alexithymia, hostility, and PTSD.

The emotional disturbance of substance abusers is often described as an inability to identify and express feelings coupled with an excess vulnerability to experience negative affect. However, there is only limited empirical support for this perspective. To validate this description, we first defined components of alexithymia, hostility, and posttraumatic stress disorder (PTSD) derived from established measures of each by conducting confirmatory factor analyses based on a self-report data set from a clinical sample of 253 alcoholics and drug addicts. We then fashioned and tested overarching latent variables representing the three aspects of emotional dysfunction (i.e., alexithymia, hostility, and PTSD) and finally tested the correlations among these overarching variables. We found a strong association between a factor labeled Bottled-Up Emotions and another labeled Neurotic Hostility (r = .62) as well as an association between PTSD and Bottled-Up Emotions (r = .66). The structure, magnitude, and intercorrelation of the latent variables did not depend on the type of psychoactive substance abused. These results support the view that features of alexithymia and hostility coexist in substance abusers and that this joint deficit is part of a broad disturbance across multiple psychological domains including pathological response to traumatic stress.

Childhood maltreatment increases risk for personality disorders during early adulthood.

BACKGROUND: Data from a community-based longitudinal study were used to investigate whether childhood abuse and neglect increases risk for personality disorders (PDs) during early adulthood. METHODS: Psychosocial and psychiatric interviews were administered to a representative community sample of 639 youths and their mothers from 2 counties in the state of New York in 1975, 1983, 1985 to 1986, and 1991 to 1993. Evidence of childhood physical abuse, sexual abuse, and neglect was obtained from New York State records and from offspring self-reports in 1991 to 1993 when they were young adults. Offspring PDs were assessed in 1991 to 1993. RESULTS: Persons with documented childhood abuse or neglect were more than 4 times as likely as those who were not abused or neglected to be diagnosed with PDs during early adulthood after age, parental education, and parental psychiatric disorders were controlled statistically. Childhood physical abuse, sexual abuse, and neglect were each associated with elevated PD symptom levels during early adulthood after other types of childhood maltreatment were controlled statistically. Of the 12 categories of DSM-IV PD symptoms, 10 were associated with childhood abuse or neglect. Different types of childhood maltreatment were associated with symptoms of specific PDs during early adulthood. CONCLUSIONS: Persons in the community who have experienced childhood abuse or neglect are considerably more likely than those who were not abused or neglected to have PDs and elevated PD symptom levels during early adulthood. Childhood abuse and neglect may contribute to the onset of some PDs.

Hospitalized adolescents' reports of sexual and physical abuse: a comparison of two self-report measures.

This study assesses the consistency of adolescents' reports of sexual and physical abuse via two self-report questionnaires with different measurement approaches and examines demographic and psychopathological characteristics that influence abuse reporting. Seventy adolescent inpatients completed the Childhood Trauma Questionnaire (CTQ) (Likert-type items are summed to form dimensional scales, and cutoff scores determine abuse status), the Traumatic Events Questionnaire--Adolescents (multiple-choice items determine abuse status) and measures of depression, suicidal ideation, and dissociative symptoms. Consistent reports of physical and sexual abuse were given by 86% and 71% of youngsters, respectively. Discrepant reporters of sexual abuse were significantly more likely to be male, whereas consistent reporters were significantly more depressed and suicidal and reported higher levels of sexual abuse and emotional and physical neglect. Adolescents, for the most part, were consistent in their responses about sexual and physical abuse on both a Likert scale and a direct-answer-format questionnaire. The CTQ had a lower threshold for detection of sexual abuse, particularly for boys.

Electrophysiologic principles and theory of stroke volume determination by thoracic electrical bioimpedance.

Thoracic electrical bioimpedance (TEB) is a harmless, noninvasive, user-friendly technology with wide patient acceptance. Stroke volume (SV) determination is important because it helps to define oxygen transport. Measurement of SV by TEB is rooted in concrete, basic electrical theory, as well as in theoretical models of electrical behavior of the human thorax and great thoracic vessels. This article is concerned with basic electrical theory as applied to TEB, signal acquisition, and the origin of the thoracic cardiogenic impedance pulse (delta Z). The appendix of the chapter features a more extensive overview of alternating current theory as applied to electrical bioimpedance.

Predicting personality pathology among adult patients with substance use disorders: effects of childhood maltreatment.

The purpose of this study was to examine predictive relationships between types of childhood maltreatment and personality disorders in a substance-abusing population. Three hundred thirty-nine drug- or alcohol-dependent patients completed a reliable and valid retrospective measure of childhood trauma, the CTQ, and a self-report inventory that assesses the entire range of DSM-III-R personality disorders, the PDQ-R. As a preliminary step, factor analyses were used to group personality disorders into the three DSM-III-R Axis II clusters (Clusters A, B, and C), although some diagnostic subclusters were also found. Structural equation modeling analyses revealed several significant paths between types of maltreatment and personality disorder clusters (and subclusters). Physical abuse and physical neglect were related to a subcluster of "psychopathic" personality disorders consisting of childhood and adult antisocial personality traits and sadistic traits. Emotional abuse emerged as a broad risk factor for personality disorders in Clusters A, B, and C. Emotional neglect was related to the traits of schizoid personality disorder, which formed its own subcluster. Finally, sexual abuse, which had been expected to predict borderline personality disorder traits, was unrelated to any personality disorder cluster. These findings support the view that child maltreatment contributes to the high prevalence of co-morbid personality disorders in addicted populations.

Hostility is associated with a heightened prolactin response to meta-chlorophenylpiperazine in abstinent cocaine addicts.

The prolactin (PRL) response to the administration of serotonin (5HT) agonists is an index of central nervous system 5HT activity. This index is blunted in association with hostile aggression in personality and depressive disorder patients without substance abuse. We tested whether the PRL response to the oral administration of the partial 5HT agonist meta-chlorophenylpiperazine (MCPP), 0.35 mg/kg, was associated with a measure of trait hostility, the Buss Durkee Hostility Inventory (BDHI), in cocaine addicts who were completing a 3-week detoxification and rehabilitation program. We also tested whether the cocaine addicts differed from healthy volunteers on their PRL, cortisol (CORT) or temperature responses to MCPP. The PRL response to MCPP was positively associated with the total score on the BDHI. There were, however, no differences in the neuroendocrine or temperature responses to MCPP between the cocaine-dependent group and the healthy volunteers once age effects were controlled for.

Assessing axis II disorders by informant interview.

Although much of personality disorder research depends on diagnostic data obtained directly from patients, this approach has rarely been compared to interviews with knowledgeable informants. The purpose of this study was to determine the diagnostic agreement between these two assessment methods, as well as their relative contribution to the formulation of consensus diagnoses. Sixty-two psychiatric patients were assessed directly with the Structured Interview for DSM-III Personality Disorders (SIDP), and were asked to nominate an informant--either a family member or friend--to provide information about the patient in an interview with the same instrument. Informant interviews were conducted blind to patient-based information whenever feasible, and diagnostic consensus was achieved by an independent review of all available data by a senior clinician. Diagnostic agreement between patient-based and informant-based personality disorder interview was poor, confirming the findings of two previous studies. Information obtained from patients tended to be given greater weight in formulating consensus diagnoses than information provided by informants. However, about one quarter of diagnostic disagreements were resolved in favor of informant-based information. In contrast to a previous study, the inclusion of informant information did not appear to reveal greater psychopathology in patients. We conclude that supplementing direct patient interview with data provided by a knowledgeable informant appears to enhance the resolution of some personality disorder diagnoses. The utility of informant interviews may depend on an analysis of the costs and benefits of this additional degree of descriptive refinement.

Validity of the Childhood Trauma Questionnaire in an adolescent psychiatric population.

OBJECTIVE: To present initial findings on the validity of a recently developed maltreatment inventory, the Childhood Trauma Questionnaire (CTQ), in a sample of adolescent psychiatric patients. METHOD: Three hundred ninety-eight male and female adolescents (aged 12 to 17 years) admitted to the inpatient service of a private psychiatric hospital were given the CTQ as part of a larger test battery. Structured interviews were also conducted with the primary therapists of 190 of the patients to obtain ratings of abuse and neglect based on all available data, including clinical interviews with patients and their relatives and information from referring clinicians and agencies. RESULTS: Principal-components analysis of the CTQ items yielded five rotated factors-emotional abuse, emotional neglect, sexual abuse, physical abuse, and physical neglect-closely replicating the factor structure in an earlier study of adult patients. The internal consistency of the CTQ factors was extremely high both in the entire sample and in every subgroup examined. When CTQ factor scores were compared with therapists' ratings in a series of logistic regression analyses, relationships between the two sets of variables were highly specific, supporting the convergent and discriminant validity of the CTQ. Finally, when therapists' ratings were used as the validity criterion, the CTQ exhibited good sensitivity for all forms of maltreatment, and satisfactory or better levels of specificity. CONCLUSIONS: These initial findings suggest that the CTQ is a sensitive and valid screening questionnaire for childhood trauma in an adolescent psychiatric inpatient setting.

Hostility is associated with a low prolactin response to meta-chlorophenylpiperazine in abstinent alcoholics.

The prolactin response to the administration of serotonin agonists is an index of central nervous system serotonin (5HT) activity. This index is blunted in association with hostile aggression in personality-disordered individuals without substance abuse. We tested whether prolactin response to the partial 5HT agonist meta-chlorophenylpiperazine (MCPP) (0.35 mg/kg po) was associated with measures of trait hostility in alcoholics who were completing a 3-week rehabilitation program after medical detoxification. We also tested whether the same 5HT index differed in the group of alcoholics compared with the healthy volunteers. The prolactin response to MCPP was inversely associated with the main index of trait hostility and was similarly inversely associated with an index of depression. There was, however, no difference in neuroendocrine or temperature responses to MCPP between the alcohol-dependent group and the healthy volunteers.

Childhood antecedents of adolescent personality disorders.

OBJECTIVE: The purpose of this study was to investigate the childhood antecedents of personality disorders that are diagnosed in adolescence. METHOD: A randomly selected community sample of 641 youths was assessed initially in childhood and followed longitudinally over 10 years. Childhood behavior ratings were based on maternal report; diagnoses of adolescent personality disorders were based on data obtained from both maternal and youth informants. Four composite measures of childhood behavior problems were used: conduct problems, depressive symptoms, anxiety/fear, and immaturity. Adolescent personality disorders were considered present only if the disorders persisted over a 2-year period. For all analyses, personality disorders were grouped into the three clusters (A, B, and C) of DSM-III-R. RESULTS: Logistic regression analyses indicated that all four of the putative childhood antecedents were associated with greater odds of an adolescent personality disorder 10 years later. Childhood conduct problems remained an independent predictor of personality disorders in all three clusters, even when other childhood problems were included in the same regression model. Additionally, depressive symptoms emerged as an independent predictor of cluster A personality disorders in boys, while immaturity was an independent predictor of cluster B personality disorders in girls. No moderating effects of age at time of childhood assessment were found. CONCLUSIONS: These results support the view that personality disorders can be traced to childhood emotional and behavioral disturbances and suggest that these problems have both general and specific relationships to adolescent personality functioning.

Levels of dissociation in detoxified substance abusers and their relationship to chronicity of alcohol and drug use.

This study compared the frequency and types of dissociative experiences reported by detoxified alcoholics and drug abusers, and examined the relationship between dissociation and recent and lifetime use of alcohol, cannabis, cocaine, and heroin. One hundred thirty-eight self-referred male veterans detoxified from alcohol (N=62) and drugs (N=76) on inpatient units at a Veterans Affairs hospital completed questionnaires including the Dissociative Experiences Scale. Three types of dissociative experiences were examined: amnesia, depersonalization/derealization, and absorption. Ninety-one of the patients were also given the Addiction Severity Index interview to determine their histories of recent (past 30 days) and lifetime drug and alcohol use. High levels of dissociation were found in both groups, with alcoholics reporting higher levels of all three types of dissociative experiences than drug addicts. Chronicity (lifetime years) of both alcohol and cocaine use was significantly correlated with dissociation scores. The amnestic effect of chronic cocaine use persisted even after controlling for the effects of chronic alcohol use. In contrast, no dissociative effects of recent (past month) use of alcohol or drugs were found. These findings suggest that dissociation may be a chronic residual effect of long-term substance abuse, including both alcohol and cocaine. Implications are discussed for the treatment of chronic substance abusers.

Initial reliability and validity of a new retrospective measure of child abuse and neglect.

OBJECTIVE: This report presents initial findings on the reliability and validity of a new retrospective measure of child abuse and neglect, the Childhood Trauma Questionnaire. METHOD: Two hundred eighty-six drug- or alcohol-dependent patients were given the Childhood Trauma Questionnaire as part of a larger test battery, and 40 of these patients were given the questionnaire again after an interval of 2 to 6 months. Sixty-eight of the patients were also given a structured interview for child abuse and neglect, the Childhood Trauma Interview, that was developed by the authors. RESULTS: Principal-components analysis of responses on the Childhood Trauma Questionnaire yielded four rotated orthogonal factors: physical and emotional abuse, emotional neglect, sexual abuse, and physical neglect. Cronbach's alpha for the factors ranged from 0.79 to 0.94, indicating high internal consistency. The Childhood Trauma Questionnaire also demonstrated good test-retest reliability over a 2- to 6-month interval (intraclass correlation = 0.88), as well as convergence with the Childhood Trauma Interview, indicating that patients' reports of child abuse and neglect based on the Childhood Trauma Questionnaire were highly stable, both over time and across type of instruments. CONCLUSIONS: These findings provide strong initial support for the reliability and validity of the Childhood Trauma Questionnaire.

Prevalence and stability of the DSM-III-R personality disorders in a community-based survey of adolescents.

OBJECTIVE: The purpose of this study was to estimate the prevalence, concurrent validity, and stability of DSM-III-R personality disorders in a large community-based sample of adolescents. METHOD: A randomly selected community sample of 733 youths ranging in age from 9 to 19 years was followed over a 2-year period. The protocol consisted of structured interviews with the adolescents and their mothers and self-report questionnaires. Algorithms for 10 DSM-III-R axis II disorders were developed to produce diagnoses at two levels of severity; these were validated against multiple indicators of distress and functional impairment. RESULTS: The overall prevalence of personality disorders peaked at age 12 in boys and at age 13 in girls and declined thereafter. Obsessive-compulsive personality disorder was the most prevalent moderate axis II disorder, narcissistic personality disorder the most prevalent severe disorder, and schizotypal personality disorder the least prevalent axis II disorder, based on both moderate and severe diagnostic thresholds. All moderate axis II disorders were associated with significantly greater odds for at least five of 12 diagnostic validators. Longitudinal follow-up revealed that although most axis II disorders did not persist over a 2-year period, subjects with disorders identified earlier remained at elevated risk for receiving a diagnosis again at follow-up. CONCLUSIONS: These findings suggest that a substantial minority of adolescents who are not in treatment qualify for DSM-III-R personality disorder diagnoses and that these diagnoses are associated with increased risk of psychological distress and functional impairment.