193 research outputs found

    Quantum Dynamics of a Hydrogen Molecule Confined in a Cylindrical Potential

    Get PDF
    We study the coupled rotation-vibration levels of a hydrogen molecule in a confining potential with cylindrical symmetry. We include the coupling between rotations and translations and show how this interaction is essential to obtain the correct degeneracies of the energy level scheme. We applied our formalism to study the dynamics of H2_{2} molecules inside a "smooth" carbon nanotube as a function of tube radius. The results are obtained both by numerical solution of the (2J+12J+1)-component radial Schrodinger equation and by developing an effective Hamiltonian to describe the splitting of a manifold of states of fixed angular momentum JJ and number of phonons, NN. For nanotube radius smaller than 3.5\approx 3.5 \AA, the confining potential has a parabolic shape and the results can be understood in terms of a simple toy model. For larger radius, the potential has the "Mexican hat" shape and therefore the H2_{2} molecule is off-centered, yielding radial and tangential translational dynamics in addition to rotational dynamics of H2_{2} molecule which we also describe by a simple model. Finally, we make several predictions for the the neutron scattering observation of various transitions between these levels.Comment: 36 pages, 8 figures, submitted to Phys. Rev. B on 12 December 200

    The role of interpersonal style in aggression and its containment in a forensic mental health setting:A correlational and pseudoprospective study of patients and nursing staff

    Get PDF
    Inpatient aggression on mental health wards is common and staff-patient interactions are frequently reported antecedents to aggression. However, relatively little is known about the precise relationship between aggression and these interactions, or their relationships with aggression and staff containment responses such as restraint and seclusion. This study aimed to determine the roles of anger and interpersonal style among mental health nurses and between nurses and patients in the occurrence of aggression and its containment. A correlational, pseudo-prospective study design was employed. n=85 inpatients and n=65 nurses were recruited from adult, low- and medium- secure wards of a secure forensic mental health service. Participants completed validated self-report anger and transactional interpersonal style measures. Inpatient aggression and containment incident data for a 3-month follow-up period were extracted from clinical records. Dyadic nurse-patient relationships were anti-complementary. Patients’ self-reported anger and staff-rated hostile interpersonal style were significantly positively correlated; staff self-reported anger and patient-rated dominant interpersonal style were also positively correlated. Patient anger predicted aggression and their interpersonal style predicted being subject to containment in the form of restraint and seclusion. There were no statistically significant differences identified on measures between staff who were and were not involved in containment. More targeted intervention for patients’ anger may have a positive impact on interpersonal style and lead to the reduction of incidents. Staff education and skills training programmes should emphasise the importance of interpersonal styles which could help to promote and enhance positive interaction

    Incremental Validity of Patients’ Self-Reported Anger Beyond Structured Professional Judgment Tools in the Prediction of Inpatient Aggression

    Get PDF
    Mental health inpatients’ self-reported violence risk predicts actual aggressive outcomes. Anger, for which there are well-evidenced interventions, commonly precedes inpatient aggression. We aimed to determine whether patients’ self-reported anger added incremental validity to violence prediction beyond routinely completed violence risk assessments. A correlational, pseudo-prospective study design was employed. N = 76 inpatients in secure hospitals completed self-report validated anger measures; routinely collected clinicians' ratings on structured professional judgment tools, and aggressive incident data for a 3-month follow-up period were extracted from clinical records. Thirty four (45%) participants were violent; self-reported anger and clinician-risk ratings were significantly positively correlated. Self-reported anger predicted aggressive outcomes but not incrementally beyond relevant risk assessment subscale and item scores. It may not be beneficial for all patients to self-report anger as part of continuous violence risk assessments, but those who score highly on anger-relevant items of risk assessment tools could be considered for further assessment to support risk-management interventions

    Isotopic and spin selectivity of H_2 adsorbed in bundles of carbon nanotubes

    Full text link
    Due to its large surface area and strongly attractive potential, a bundle of carbon nanotubes is an ideal substrate material for gas storage. In addition, adsorption in nanotubes can be exploited in order to separate the components of a mixture. In this paper, we investigate the preferential adsorption of D_2 versus H_2(isotope selectivity) and of ortho versus para(spin selectivity) molecules confined in the one-dimensional grooves and interstitial channels of carbon nanotube bundles. We perform selectivity calculations in the low coverage regime, neglecting interactions between adsorbate molecules. We find substantial spin selectivity for a range of temperatures up to 100 K, and even greater isotope selectivity for an extended range of temperatures,up to 300 K. This isotope selectivity is consistent with recent experimental data, which exhibit a large difference between the isosteric heats of D_2 and H_2 adsorbed in these bundles.Comment: Paper submitted to Phys.Rev. B; 17 pages, 2 tables, 6 figure

    Statistical Survey of Type III Radio Bursts at Long Wavelengths Observed by the Solar TErrestrial RElations Observatory (STEREO)/Waves Instruments: Radio Flux Density Variations with Frequency

    Full text link
    We have performed a statistical study of 152152 Type III radio bursts observed by Solar TErrestrial RElations Observatory (STEREO)/Waves between May 2007 and February 2013. We have investigated the flux density between 125125kHz and 1616MHz. Both high- and low-frequency cutoffs have been observed in 6060\,% of events suggesting an important role of propagation. As already reported by previous authors, we observed that the maximum flux density occurs at 11MHz on both spacecraft. We have developed a simplified analytical model of the flux density as a function of radial distance and compared it to the STEREO/Waves data.Comment: published in Solar Physic

    Female firesetters: gender associated psychological and psychopathological features

    Get PDF
    Objective: Female firesetters are reported to commit nearly a third of deliberately set fires, yet there are limited studies examining the characteristics that distinguish them from suitable comparison groups. The aim of this study is to compare incarcerated female firesetters with incarcerated male firesetters and female offender controls on psychopathological and psychological features that could be targeted via therapeutic interventions. Method: Sixty-five female firesetters, 128 male firesetters, and 63 female offenders were recruited from the prison estate. Participants completed a battery of validated tools assessing psychiatric traits and psychological characteristics (i.e., inappropriate fire interest, emotion/self-regulation, social competence, self-concept, offense-supportive attitudes, and boredom proneness) highlighted in the existing literature. Results: Major depression and an internal locus of control distinguished female firesetters from male firesetters. Alcohol dependence, serious/problematic fire interest, and more effective anger regulation distinguished female firesetters from the female offender control group. Conclusions: This is the first study to examine differences between female firesetters, male firesetters, and female control offenders on both psychopathological features and psychological traits. These findings highlight the gender-specific and offence-specific needs of female firesetters that clinicians need to consider when implementing programs that ensure client responsivity. Keywords: firesetting, arson, psychopathology, female offender

    Assessing the co-occurrence of intimate partner violence domains across the life-course: relating typologies to mental health

    Get PDF
    Background: The inter-generational transmission of violence (ITV) hypothesis and polyvictimisation have been studied extensively. The extant evidence suggests that individuals from violent families are at increased risk of subsequent intimate partner violence (IPV) and that a proportion of individuals experience victimisation across multiple rather than single IPV domains. Both ITV and polyvictimisation are shown to increase the risk of psychiatric morbidity, alcohol use, and anger expression. Objective: The current study aimed to 1) ascertain if underlying typologies of victimisation across the life-course and over multiple victimisation domains were present and 2) ascertain if groupings differed on mean scores of posttraumatic stress disorder (PTSD), depression, alcohol use, and anger expression. Method: University students (N=318) were queried in relation to victimisation experiences and psychological well-being. Responses across multiple domains of IPV spanning the life-course were used in a latent profile analysis. ANOVA was subsequently used to determine if profiles differed in their mean scores on PTSD, depression, alcohol use, and anger expression. Results: Three distinct profiles were identified; one of which comprised individuals who experienced “life-course polyvictimisation,” another showing individuals who experienced “witnessing parental victimisation,” and one which experienced “psychological victimisation only.” Life-course polyvictims scored the highest across most assessed measures. Conclusion: Witnessing severe physical aggression and injury in parental relationships as a child has an interesting impact on the ITV into adolescence and adulthood. Life-course polyvictims are shown to experience increased levels of psychiatric morbidity and issues with alcohol misuse and anger expression
    corecore